diff --git a/Makefile b/Makefile index 74300aef6..0df75db0b 100644 --- a/Makefile +++ b/Makefile @@ -147,3 +147,11 @@ lint: clean: rm $(BINDIR)/* + +CLANG ?= clang-14 +CFLAGS := -O2 -g -Wall -Werror $(CFLAGS) + +ebpf: export BPF_CLANG := $(CLANG) +ebpf: export BPF_CFLAGS := $(CFLAGS) +ebpf: + cd component/ebpf/ && go generate ./... \ No newline at end of file diff --git a/component/ebpf/bpf/bpf_endian.h b/component/ebpf/bpf/bpf_endian.h new file mode 100644 index 000000000..ec9db4fec --- /dev/null +++ b/component/ebpf/bpf/bpf_endian.h @@ -0,0 +1,99 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ +#ifndef __BPF_ENDIAN__ +#define __BPF_ENDIAN__ + +/* + * Isolate byte #n and put it into byte #m, for __u##b type. + * E.g., moving byte #6 (nnnnnnnn) into byte #1 (mmmmmmmm) for __u64: + * 1) xxxxxxxx nnnnnnnn xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx mmmmmmmm xxxxxxxx + * 2) nnnnnnnn xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxxx mmmmmmmm xxxxxxxx 00000000 + * 3) 00000000 00000000 00000000 00000000 00000000 00000000 00000000 nnnnnnnn + * 4) 00000000 00000000 00000000 00000000 00000000 00000000 nnnnnnnn 00000000 + */ +#define ___bpf_mvb(x, b, n, m) ((__u##b)(x) << (b-(n+1)*8) >> (b-8) << (m*8)) + +#define ___bpf_swab16(x) ((__u16)( \ + ___bpf_mvb(x, 16, 0, 1) | \ + ___bpf_mvb(x, 16, 1, 0))) + +#define ___bpf_swab32(x) ((__u32)( \ + ___bpf_mvb(x, 32, 0, 3) | \ + ___bpf_mvb(x, 32, 1, 2) | \ + ___bpf_mvb(x, 32, 2, 1) | \ + ___bpf_mvb(x, 32, 3, 0))) + +#define ___bpf_swab64(x) ((__u64)( \ + ___bpf_mvb(x, 64, 0, 7) | \ + ___bpf_mvb(x, 64, 1, 6) | \ + ___bpf_mvb(x, 64, 2, 5) | \ + ___bpf_mvb(x, 64, 3, 4) | \ + ___bpf_mvb(x, 64, 4, 3) | \ + ___bpf_mvb(x, 64, 5, 2) | \ + ___bpf_mvb(x, 64, 6, 1) | \ + ___bpf_mvb(x, 64, 7, 0))) + +/* LLVM's BPF target selects the endianness of the CPU + * it compiles on, or the user specifies (bpfel/bpfeb), + * respectively. The used __BYTE_ORDER__ is defined by + * the compiler, we cannot rely on __BYTE_ORDER from + * libc headers, since it doesn't reflect the actual + * requested byte order. + * + * Note, LLVM's BPF target has different __builtin_bswapX() + * semantics. It does map to BPF_ALU | BPF_END | BPF_TO_BE + * in bpfel and bpfeb case, which means below, that we map + * to cpu_to_be16(). We could use it unconditionally in BPF + * case, but better not rely on it, so that this header here + * can be used from application and BPF program side, which + * use different targets. + */ +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ +# define __bpf_ntohs(x) __builtin_bswap16(x) +# define __bpf_htons(x) __builtin_bswap16(x) +# define __bpf_constant_ntohs(x) ___bpf_swab16(x) +# define __bpf_constant_htons(x) ___bpf_swab16(x) +# define __bpf_ntohl(x) __builtin_bswap32(x) +# define __bpf_htonl(x) __builtin_bswap32(x) +# define __bpf_constant_ntohl(x) ___bpf_swab32(x) +# define __bpf_constant_htonl(x) ___bpf_swab32(x) +# define __bpf_be64_to_cpu(x) __builtin_bswap64(x) +# define __bpf_cpu_to_be64(x) __builtin_bswap64(x) +# define __bpf_constant_be64_to_cpu(x) ___bpf_swab64(x) +# define __bpf_constant_cpu_to_be64(x) ___bpf_swab64(x) +#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ +# define __bpf_ntohs(x) (x) +# define __bpf_htons(x) (x) +# define __bpf_constant_ntohs(x) (x) +# define __bpf_constant_htons(x) (x) +# define __bpf_ntohl(x) (x) +# define __bpf_htonl(x) (x) +# define __bpf_constant_ntohl(x) (x) +# define __bpf_constant_htonl(x) (x) +# define __bpf_be64_to_cpu(x) (x) +# define __bpf_cpu_to_be64(x) (x) +# define __bpf_constant_be64_to_cpu(x) (x) +# define __bpf_constant_cpu_to_be64(x) (x) +#else +# error "Fix your compiler's __BYTE_ORDER__?!" +#endif + +#define bpf_htons(x) \ + (__builtin_constant_p(x) ? \ + __bpf_constant_htons(x) : __bpf_htons(x)) +#define bpf_ntohs(x) \ + (__builtin_constant_p(x) ? \ + __bpf_constant_ntohs(x) : __bpf_ntohs(x)) +#define bpf_htonl(x) \ + (__builtin_constant_p(x) ? \ + __bpf_constant_htonl(x) : __bpf_htonl(x)) +#define bpf_ntohl(x) \ + (__builtin_constant_p(x) ? \ + __bpf_constant_ntohl(x) : __bpf_ntohl(x)) +#define bpf_cpu_to_be64(x) \ + (__builtin_constant_p(x) ? \ + __bpf_constant_cpu_to_be64(x) : __bpf_cpu_to_be64(x)) +#define bpf_be64_to_cpu(x) \ + (__builtin_constant_p(x) ? \ + __bpf_constant_be64_to_cpu(x) : __bpf_be64_to_cpu(x)) + +#endif /* __BPF_ENDIAN__ */ diff --git a/component/ebpf/bpf/bpf_helper_defs.h b/component/ebpf/bpf/bpf_helper_defs.h new file mode 100644 index 000000000..8a4edf613 --- /dev/null +++ b/component/ebpf/bpf/bpf_helper_defs.h @@ -0,0 +1,4139 @@ +/* This is auto-generated file. See bpf_doc.py for details. */ + +/* Forward declarations of BPF structs */ +struct bpf_fib_lookup; +struct bpf_sk_lookup; +struct bpf_perf_event_data; +struct bpf_perf_event_value; +struct bpf_pidns_info; +struct bpf_redir_neigh; +struct bpf_sock; +struct bpf_sock_addr; +struct bpf_sock_ops; +struct bpf_sock_tuple; +struct bpf_spin_lock; +struct bpf_sysctl; +struct bpf_tcp_sock; +struct bpf_tunnel_key; +struct bpf_xfrm_state; +struct linux_binprm; +struct pt_regs; +struct sk_reuseport_md; +struct sockaddr; +struct tcphdr; +struct seq_file; +struct tcp6_sock; +struct tcp_sock; +struct tcp_timewait_sock; +struct tcp_request_sock; +struct udp6_sock; +struct unix_sock; +struct task_struct; +struct __sk_buff; +struct sk_msg_md; +struct xdp_md; +struct path; +struct btf_ptr; +struct inode; +struct socket; +struct file; +struct bpf_timer; + +/* + * bpf_map_lookup_elem + * + * Perform a lookup in *map* for an entry associated to *key*. + * + * Returns + * Map value associated to *key*, or **NULL** if no entry was + * found. + */ +static void *(*bpf_map_lookup_elem)(void *map, const void *key) = (void *) 1; + +/* + * bpf_map_update_elem + * + * Add or update the value of the entry associated to *key* in + * *map* with *value*. *flags* is one of: + * + * **BPF_NOEXIST** + * The entry for *key* must not exist in the map. + * **BPF_EXIST** + * The entry for *key* must already exist in the map. + * **BPF_ANY** + * No condition on the existence of the entry for *key*. + * + * Flag value **BPF_NOEXIST** cannot be used for maps of types + * **BPF_MAP_TYPE_ARRAY** or **BPF_MAP_TYPE_PERCPU_ARRAY** (all + * elements always exist), the helper would return an error. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_map_update_elem)(void *map, const void *key, const void *value, __u64 flags) = (void *) 2; + +/* + * bpf_map_delete_elem + * + * Delete entry with *key* from *map*. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_map_delete_elem)(void *map, const void *key) = (void *) 3; + +/* + * bpf_probe_read + * + * For tracing programs, safely attempt to read *size* bytes from + * kernel space address *unsafe_ptr* and store the data in *dst*. + * + * Generally, use **bpf_probe_read_user**\ () or + * **bpf_probe_read_kernel**\ () instead. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_probe_read)(void *dst, __u32 size, const void *unsafe_ptr) = (void *) 4; + +/* + * bpf_ktime_get_ns + * + * Return the time elapsed since system boot, in nanoseconds. + * Does not include time the system was suspended. + * See: **clock_gettime**\ (**CLOCK_MONOTONIC**) + * + * Returns + * Current *ktime*. + */ +static __u64 (*bpf_ktime_get_ns)(void) = (void *) 5; + +/* + * bpf_trace_printk + * + * This helper is a "printk()-like" facility for debugging. It + * prints a message defined by format *fmt* (of size *fmt_size*) + * to file *\/sys/kernel/debug/tracing/trace* from DebugFS, if + * available. It can take up to three additional **u64** + * arguments (as an eBPF helpers, the total number of arguments is + * limited to five). + * + * Each time the helper is called, it appends a line to the trace. + * Lines are discarded while *\/sys/kernel/debug/tracing/trace* is + * open, use *\/sys/kernel/debug/tracing/trace_pipe* to avoid this. + * The format of the trace is customizable, and the exact output + * one will get depends on the options set in + * *\/sys/kernel/debug/tracing/trace_options* (see also the + * *README* file under the same directory). However, it usually + * defaults to something like: + * + * :: + * + * telnet-470 [001] .N.. 419421.045894: 0x00000001: + * + * In the above: + * + * * ``telnet`` is the name of the current task. + * * ``470`` is the PID of the current task. + * * ``001`` is the CPU number on which the task is + * running. + * * In ``.N..``, each character refers to a set of + * options (whether irqs are enabled, scheduling + * options, whether hard/softirqs are running, level of + * preempt_disabled respectively). **N** means that + * **TIF_NEED_RESCHED** and **PREEMPT_NEED_RESCHED** + * are set. + * * ``419421.045894`` is a timestamp. + * * ``0x00000001`` is a fake value used by BPF for the + * instruction pointer register. + * * ```` is the message formatted with + * *fmt*. + * + * The conversion specifiers supported by *fmt* are similar, but + * more limited than for printk(). They are **%d**, **%i**, + * **%u**, **%x**, **%ld**, **%li**, **%lu**, **%lx**, **%lld**, + * **%lli**, **%llu**, **%llx**, **%p**, **%s**. No modifier (size + * of field, padding with zeroes, etc.) is available, and the + * helper will return **-EINVAL** (but print nothing) if it + * encounters an unknown specifier. + * + * Also, note that **bpf_trace_printk**\ () is slow, and should + * only be used for debugging purposes. For this reason, a notice + * block (spanning several lines) is printed to kernel logs and + * states that the helper should not be used "for production use" + * the first time this helper is used (or more precisely, when + * **trace_printk**\ () buffers are allocated). For passing values + * to user space, perf events should be preferred. + * + * Returns + * The number of bytes written to the buffer, or a negative error + * in case of failure. + */ +static long (*bpf_trace_printk)(const char *fmt, __u32 fmt_size, ...) = (void *) 6; + +/* + * bpf_get_prandom_u32 + * + * Get a pseudo-random number. + * + * From a security point of view, this helper uses its own + * pseudo-random internal state, and cannot be used to infer the + * seed of other random functions in the kernel. However, it is + * essential to note that the generator used by the helper is not + * cryptographically secure. + * + * Returns + * A random 32-bit unsigned value. + */ +static __u32 (*bpf_get_prandom_u32)(void) = (void *) 7; + +/* + * bpf_get_smp_processor_id + * + * Get the SMP (symmetric multiprocessing) processor id. Note that + * all programs run with migration disabled, which means that the + * SMP processor id is stable during all the execution of the + * program. + * + * Returns + * The SMP id of the processor running the program. + */ +static __u32 (*bpf_get_smp_processor_id)(void) = (void *) 8; + +/* + * bpf_skb_store_bytes + * + * Store *len* bytes from address *from* into the packet + * associated to *skb*, at *offset*. *flags* are a combination of + * **BPF_F_RECOMPUTE_CSUM** (automatically recompute the + * checksum for the packet after storing the bytes) and + * **BPF_F_INVALIDATE_HASH** (set *skb*\ **->hash**, *skb*\ + * **->swhash** and *skb*\ **->l4hash** to 0). + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_store_bytes)(struct __sk_buff *skb, __u32 offset, const void *from, __u32 len, __u64 flags) = (void *) 9; + +/* + * bpf_l3_csum_replace + * + * Recompute the layer 3 (e.g. IP) checksum for the packet + * associated to *skb*. Computation is incremental, so the helper + * must know the former value of the header field that was + * modified (*from*), the new value of this field (*to*), and the + * number of bytes (2 or 4) for this field, stored in *size*. + * Alternatively, it is possible to store the difference between + * the previous and the new values of the header field in *to*, by + * setting *from* and *size* to 0. For both methods, *offset* + * indicates the location of the IP checksum within the packet. + * + * This helper works in combination with **bpf_csum_diff**\ (), + * which does not update the checksum in-place, but offers more + * flexibility and can handle sizes larger than 2 or 4 for the + * checksum to update. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_l3_csum_replace)(struct __sk_buff *skb, __u32 offset, __u64 from, __u64 to, __u64 size) = (void *) 10; + +/* + * bpf_l4_csum_replace + * + * Recompute the layer 4 (e.g. TCP, UDP or ICMP) checksum for the + * packet associated to *skb*. Computation is incremental, so the + * helper must know the former value of the header field that was + * modified (*from*), the new value of this field (*to*), and the + * number of bytes (2 or 4) for this field, stored on the lowest + * four bits of *flags*. Alternatively, it is possible to store + * the difference between the previous and the new values of the + * header field in *to*, by setting *from* and the four lowest + * bits of *flags* to 0. For both methods, *offset* indicates the + * location of the IP checksum within the packet. In addition to + * the size of the field, *flags* can be added (bitwise OR) actual + * flags. With **BPF_F_MARK_MANGLED_0**, a null checksum is left + * untouched (unless **BPF_F_MARK_ENFORCE** is added as well), and + * for updates resulting in a null checksum the value is set to + * **CSUM_MANGLED_0** instead. Flag **BPF_F_PSEUDO_HDR** indicates + * the checksum is to be computed against a pseudo-header. + * + * This helper works in combination with **bpf_csum_diff**\ (), + * which does not update the checksum in-place, but offers more + * flexibility and can handle sizes larger than 2 or 4 for the + * checksum to update. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_l4_csum_replace)(struct __sk_buff *skb, __u32 offset, __u64 from, __u64 to, __u64 flags) = (void *) 11; + +/* + * bpf_tail_call + * + * This special helper is used to trigger a "tail call", or in + * other words, to jump into another eBPF program. The same stack + * frame is used (but values on stack and in registers for the + * caller are not accessible to the callee). This mechanism allows + * for program chaining, either for raising the maximum number of + * available eBPF instructions, or to execute given programs in + * conditional blocks. For security reasons, there is an upper + * limit to the number of successive tail calls that can be + * performed. + * + * Upon call of this helper, the program attempts to jump into a + * program referenced at index *index* in *prog_array_map*, a + * special map of type **BPF_MAP_TYPE_PROG_ARRAY**, and passes + * *ctx*, a pointer to the context. + * + * If the call succeeds, the kernel immediately runs the first + * instruction of the new program. This is not a function call, + * and it never returns to the previous program. If the call + * fails, then the helper has no effect, and the caller continues + * to run its subsequent instructions. A call can fail if the + * destination program for the jump does not exist (i.e. *index* + * is superior to the number of entries in *prog_array_map*), or + * if the maximum number of tail calls has been reached for this + * chain of programs. This limit is defined in the kernel by the + * macro **MAX_TAIL_CALL_CNT** (not accessible to user space), + * which is currently set to 33. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_tail_call)(void *ctx, void *prog_array_map, __u32 index) = (void *) 12; + +/* + * bpf_clone_redirect + * + * Clone and redirect the packet associated to *skb* to another + * net device of index *ifindex*. Both ingress and egress + * interfaces can be used for redirection. The **BPF_F_INGRESS** + * value in *flags* is used to make the distinction (ingress path + * is selected if the flag is present, egress path otherwise). + * This is the only flag supported for now. + * + * In comparison with **bpf_redirect**\ () helper, + * **bpf_clone_redirect**\ () has the associated cost of + * duplicating the packet buffer, but this can be executed out of + * the eBPF program. Conversely, **bpf_redirect**\ () is more + * efficient, but it is handled through an action code where the + * redirection happens only after the eBPF program has returned. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_clone_redirect)(struct __sk_buff *skb, __u32 ifindex, __u64 flags) = (void *) 13; + +/* + * bpf_get_current_pid_tgid + * + * + * Returns + * A 64-bit integer containing the current tgid and pid, and + * created as such: + * *current_task*\ **->tgid << 32 \|** + * *current_task*\ **->pid**. + */ +static __u64 (*bpf_get_current_pid_tgid)(void) = (void *) 14; + +/* + * bpf_get_current_uid_gid + * + * + * Returns + * A 64-bit integer containing the current GID and UID, and + * created as such: *current_gid* **<< 32 \|** *current_uid*. + */ +static __u64 (*bpf_get_current_uid_gid)(void) = (void *) 15; + +/* + * bpf_get_current_comm + * + * Copy the **comm** attribute of the current task into *buf* of + * *size_of_buf*. The **comm** attribute contains the name of + * the executable (excluding the path) for the current task. The + * *size_of_buf* must be strictly positive. On success, the + * helper makes sure that the *buf* is NUL-terminated. On failure, + * it is filled with zeroes. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_get_current_comm)(void *buf, __u32 size_of_buf) = (void *) 16; + +/* + * bpf_get_cgroup_classid + * + * Retrieve the classid for the current task, i.e. for the net_cls + * cgroup to which *skb* belongs. + * + * This helper can be used on TC egress path, but not on ingress. + * + * The net_cls cgroup provides an interface to tag network packets + * based on a user-provided identifier for all traffic coming from + * the tasks belonging to the related cgroup. See also the related + * kernel documentation, available from the Linux sources in file + * *Documentation/admin-guide/cgroup-v1/net_cls.rst*. + * + * The Linux kernel has two versions for cgroups: there are + * cgroups v1 and cgroups v2. Both are available to users, who can + * use a mixture of them, but note that the net_cls cgroup is for + * cgroup v1 only. This makes it incompatible with BPF programs + * run on cgroups, which is a cgroup-v2-only feature (a socket can + * only hold data for one version of cgroups at a time). + * + * This helper is only available is the kernel was compiled with + * the **CONFIG_CGROUP_NET_CLASSID** configuration option set to + * "**y**" or to "**m**". + * + * Returns + * The classid, or 0 for the default unconfigured classid. + */ +static __u32 (*bpf_get_cgroup_classid)(struct __sk_buff *skb) = (void *) 17; + +/* + * bpf_skb_vlan_push + * + * Push a *vlan_tci* (VLAN tag control information) of protocol + * *vlan_proto* to the packet associated to *skb*, then update + * the checksum. Note that if *vlan_proto* is different from + * **ETH_P_8021Q** and **ETH_P_8021AD**, it is considered to + * be **ETH_P_8021Q**. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_vlan_push)(struct __sk_buff *skb, __be16 vlan_proto, __u16 vlan_tci) = (void *) 18; + +/* + * bpf_skb_vlan_pop + * + * Pop a VLAN header from the packet associated to *skb*. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_vlan_pop)(struct __sk_buff *skb) = (void *) 19; + +/* + * bpf_skb_get_tunnel_key + * + * Get tunnel metadata. This helper takes a pointer *key* to an + * empty **struct bpf_tunnel_key** of **size**, that will be + * filled with tunnel metadata for the packet associated to *skb*. + * The *flags* can be set to **BPF_F_TUNINFO_IPV6**, which + * indicates that the tunnel is based on IPv6 protocol instead of + * IPv4. + * + * The **struct bpf_tunnel_key** is an object that generalizes the + * principal parameters used by various tunneling protocols into a + * single struct. This way, it can be used to easily make a + * decision based on the contents of the encapsulation header, + * "summarized" in this struct. In particular, it holds the IP + * address of the remote end (IPv4 or IPv6, depending on the case) + * in *key*\ **->remote_ipv4** or *key*\ **->remote_ipv6**. Also, + * this struct exposes the *key*\ **->tunnel_id**, which is + * generally mapped to a VNI (Virtual Network Identifier), making + * it programmable together with the **bpf_skb_set_tunnel_key**\ + * () helper. + * + * Let's imagine that the following code is part of a program + * attached to the TC ingress interface, on one end of a GRE + * tunnel, and is supposed to filter out all messages coming from + * remote ends with IPv4 address other than 10.0.0.1: + * + * :: + * + * int ret; + * struct bpf_tunnel_key key = {}; + * + * ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0); + * if (ret < 0) + * return TC_ACT_SHOT; // drop packet + * + * if (key.remote_ipv4 != 0x0a000001) + * return TC_ACT_SHOT; // drop packet + * + * return TC_ACT_OK; // accept packet + * + * This interface can also be used with all encapsulation devices + * that can operate in "collect metadata" mode: instead of having + * one network device per specific configuration, the "collect + * metadata" mode only requires a single device where the + * configuration can be extracted from this helper. + * + * This can be used together with various tunnels such as VXLan, + * Geneve, GRE or IP in IP (IPIP). + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_get_tunnel_key)(struct __sk_buff *skb, struct bpf_tunnel_key *key, __u32 size, __u64 flags) = (void *) 20; + +/* + * bpf_skb_set_tunnel_key + * + * Populate tunnel metadata for packet associated to *skb.* The + * tunnel metadata is set to the contents of *key*, of *size*. The + * *flags* can be set to a combination of the following values: + * + * **BPF_F_TUNINFO_IPV6** + * Indicate that the tunnel is based on IPv6 protocol + * instead of IPv4. + * **BPF_F_ZERO_CSUM_TX** + * For IPv4 packets, add a flag to tunnel metadata + * indicating that checksum computation should be skipped + * and checksum set to zeroes. + * **BPF_F_DONT_FRAGMENT** + * Add a flag to tunnel metadata indicating that the + * packet should not be fragmented. + * **BPF_F_SEQ_NUMBER** + * Add a flag to tunnel metadata indicating that a + * sequence number should be added to tunnel header before + * sending the packet. This flag was added for GRE + * encapsulation, but might be used with other protocols + * as well in the future. + * + * Here is a typical usage on the transmit path: + * + * :: + * + * struct bpf_tunnel_key key; + * populate key ... + * bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0); + * bpf_clone_redirect(skb, vxlan_dev_ifindex, 0); + * + * See also the description of the **bpf_skb_get_tunnel_key**\ () + * helper for additional information. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_set_tunnel_key)(struct __sk_buff *skb, struct bpf_tunnel_key *key, __u32 size, __u64 flags) = (void *) 21; + +/* + * bpf_perf_event_read + * + * Read the value of a perf event counter. This helper relies on a + * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of + * the perf event counter is selected when *map* is updated with + * perf event file descriptors. The *map* is an array whose size + * is the number of available CPUs, and each cell contains a value + * relative to one CPU. The value to retrieve is indicated by + * *flags*, that contains the index of the CPU to look up, masked + * with **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to + * **BPF_F_CURRENT_CPU** to indicate that the value for the + * current CPU should be retrieved. + * + * Note that before Linux 4.13, only hardware perf event can be + * retrieved. + * + * Also, be aware that the newer helper + * **bpf_perf_event_read_value**\ () is recommended over + * **bpf_perf_event_read**\ () in general. The latter has some ABI + * quirks where error and counter value are used as a return code + * (which is wrong to do since ranges may overlap). This issue is + * fixed with **bpf_perf_event_read_value**\ (), which at the same + * time provides more features over the **bpf_perf_event_read**\ + * () interface. Please refer to the description of + * **bpf_perf_event_read_value**\ () for details. + * + * Returns + * The value of the perf event counter read from the map, or a + * negative error code in case of failure. + */ +static __u64 (*bpf_perf_event_read)(void *map, __u64 flags) = (void *) 22; + +/* + * bpf_redirect + * + * Redirect the packet to another net device of index *ifindex*. + * This helper is somewhat similar to **bpf_clone_redirect**\ + * (), except that the packet is not cloned, which provides + * increased performance. + * + * Except for XDP, both ingress and egress interfaces can be used + * for redirection. The **BPF_F_INGRESS** value in *flags* is used + * to make the distinction (ingress path is selected if the flag + * is present, egress path otherwise). Currently, XDP only + * supports redirection to the egress interface, and accepts no + * flag at all. + * + * The same effect can also be attained with the more generic + * **bpf_redirect_map**\ (), which uses a BPF map to store the + * redirect target instead of providing it directly to the helper. + * + * Returns + * For XDP, the helper returns **XDP_REDIRECT** on success or + * **XDP_ABORTED** on error. For other program types, the values + * are **TC_ACT_REDIRECT** on success or **TC_ACT_SHOT** on + * error. + */ +static long (*bpf_redirect)(__u32 ifindex, __u64 flags) = (void *) 23; + +/* + * bpf_get_route_realm + * + * Retrieve the realm or the route, that is to say the + * **tclassid** field of the destination for the *skb*. The + * identifier retrieved is a user-provided tag, similar to the + * one used with the net_cls cgroup (see description for + * **bpf_get_cgroup_classid**\ () helper), but here this tag is + * held by a route (a destination entry), not by a task. + * + * Retrieving this identifier works with the clsact TC egress hook + * (see also **tc-bpf(8)**), or alternatively on conventional + * classful egress qdiscs, but not on TC ingress path. In case of + * clsact TC egress hook, this has the advantage that, internally, + * the destination entry has not been dropped yet in the transmit + * path. Therefore, the destination entry does not need to be + * artificially held via **netif_keep_dst**\ () for a classful + * qdisc until the *skb* is freed. + * + * This helper is available only if the kernel was compiled with + * **CONFIG_IP_ROUTE_CLASSID** configuration option. + * + * Returns + * The realm of the route for the packet associated to *skb*, or 0 + * if none was found. + */ +static __u32 (*bpf_get_route_realm)(struct __sk_buff *skb) = (void *) 24; + +/* + * bpf_perf_event_output + * + * Write raw *data* blob into a special BPF perf event held by + * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf + * event must have the following attributes: **PERF_SAMPLE_RAW** + * as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and + * **PERF_COUNT_SW_BPF_OUTPUT** as **config**. + * + * The *flags* are used to indicate the index in *map* for which + * the value must be put, masked with **BPF_F_INDEX_MASK**. + * Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU** + * to indicate that the index of the current CPU core should be + * used. + * + * The value to write, of *size*, is passed through eBPF stack and + * pointed by *data*. + * + * The context of the program *ctx* needs also be passed to the + * helper. + * + * On user space, a program willing to read the values needs to + * call **perf_event_open**\ () on the perf event (either for + * one or for all CPUs) and to store the file descriptor into the + * *map*. This must be done before the eBPF program can send data + * into it. An example is available in file + * *samples/bpf/trace_output_user.c* in the Linux kernel source + * tree (the eBPF program counterpart is in + * *samples/bpf/trace_output_kern.c*). + * + * **bpf_perf_event_output**\ () achieves better performance + * than **bpf_trace_printk**\ () for sharing data with user + * space, and is much better suitable for streaming data from eBPF + * programs. + * + * Note that this helper is not restricted to tracing use cases + * and can be used with programs attached to TC or XDP as well, + * where it allows for passing data to user space listeners. Data + * can be: + * + * * Only custom structs, + * * Only the packet payload, or + * * A combination of both. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_perf_event_output)(void *ctx, void *map, __u64 flags, void *data, __u64 size) = (void *) 25; + +/* + * bpf_skb_load_bytes + * + * This helper was provided as an easy way to load data from a + * packet. It can be used to load *len* bytes from *offset* from + * the packet associated to *skb*, into the buffer pointed by + * *to*. + * + * Since Linux 4.7, usage of this helper has mostly been replaced + * by "direct packet access", enabling packet data to be + * manipulated with *skb*\ **->data** and *skb*\ **->data_end** + * pointing respectively to the first byte of packet data and to + * the byte after the last byte of packet data. However, it + * remains useful if one wishes to read large quantities of data + * at once from a packet into the eBPF stack. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_load_bytes)(const void *skb, __u32 offset, void *to, __u32 len) = (void *) 26; + +/* + * bpf_get_stackid + * + * Walk a user or a kernel stack and return its id. To achieve + * this, the helper needs *ctx*, which is a pointer to the context + * on which the tracing program is executed, and a pointer to a + * *map* of type **BPF_MAP_TYPE_STACK_TRACE**. + * + * The last argument, *flags*, holds the number of stack frames to + * skip (from 0 to 255), masked with + * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set + * a combination of the following flags: + * + * **BPF_F_USER_STACK** + * Collect a user space stack instead of a kernel stack. + * **BPF_F_FAST_STACK_CMP** + * Compare stacks by hash only. + * **BPF_F_REUSE_STACKID** + * If two different stacks hash into the same *stackid*, + * discard the old one. + * + * The stack id retrieved is a 32 bit long integer handle which + * can be further combined with other data (including other stack + * ids) and used as a key into maps. This can be useful for + * generating a variety of graphs (such as flame graphs or off-cpu + * graphs). + * + * For walking a stack, this helper is an improvement over + * **bpf_probe_read**\ (), which can be used with unrolled loops + * but is not efficient and consumes a lot of eBPF instructions. + * Instead, **bpf_get_stackid**\ () can collect up to + * **PERF_MAX_STACK_DEPTH** both kernel and user frames. Note that + * this limit can be controlled with the **sysctl** program, and + * that it should be manually increased in order to profile long + * user stacks (such as stacks for Java programs). To do so, use: + * + * :: + * + * # sysctl kernel.perf_event_max_stack= + * + * Returns + * The positive or null stack id on success, or a negative error + * in case of failure. + */ +static long (*bpf_get_stackid)(void *ctx, void *map, __u64 flags) = (void *) 27; + +/* + * bpf_csum_diff + * + * Compute a checksum difference, from the raw buffer pointed by + * *from*, of length *from_size* (that must be a multiple of 4), + * towards the raw buffer pointed by *to*, of size *to_size* + * (same remark). An optional *seed* can be added to the value + * (this can be cascaded, the seed may come from a previous call + * to the helper). + * + * This is flexible enough to be used in several ways: + * + * * With *from_size* == 0, *to_size* > 0 and *seed* set to + * checksum, it can be used when pushing new data. + * * With *from_size* > 0, *to_size* == 0 and *seed* set to + * checksum, it can be used when removing data from a packet. + * * With *from_size* > 0, *to_size* > 0 and *seed* set to 0, it + * can be used to compute a diff. Note that *from_size* and + * *to_size* do not need to be equal. + * + * This helper can be used in combination with + * **bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ (), to + * which one can feed in the difference computed with + * **bpf_csum_diff**\ (). + * + * Returns + * The checksum result, or a negative error code in case of + * failure. + */ +static __s64 (*bpf_csum_diff)(__be32 *from, __u32 from_size, __be32 *to, __u32 to_size, __wsum seed) = (void *) 28; + +/* + * bpf_skb_get_tunnel_opt + * + * Retrieve tunnel options metadata for the packet associated to + * *skb*, and store the raw tunnel option data to the buffer *opt* + * of *size*. + * + * This helper can be used with encapsulation devices that can + * operate in "collect metadata" mode (please refer to the related + * note in the description of **bpf_skb_get_tunnel_key**\ () for + * more details). A particular example where this can be used is + * in combination with the Geneve encapsulation protocol, where it + * allows for pushing (with **bpf_skb_get_tunnel_opt**\ () helper) + * and retrieving arbitrary TLVs (Type-Length-Value headers) from + * the eBPF program. This allows for full customization of these + * headers. + * + * Returns + * The size of the option data retrieved. + */ +static long (*bpf_skb_get_tunnel_opt)(struct __sk_buff *skb, void *opt, __u32 size) = (void *) 29; + +/* + * bpf_skb_set_tunnel_opt + * + * Set tunnel options metadata for the packet associated to *skb* + * to the option data contained in the raw buffer *opt* of *size*. + * + * See also the description of the **bpf_skb_get_tunnel_opt**\ () + * helper for additional information. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_set_tunnel_opt)(struct __sk_buff *skb, void *opt, __u32 size) = (void *) 30; + +/* + * bpf_skb_change_proto + * + * Change the protocol of the *skb* to *proto*. Currently + * supported are transition from IPv4 to IPv6, and from IPv6 to + * IPv4. The helper takes care of the groundwork for the + * transition, including resizing the socket buffer. The eBPF + * program is expected to fill the new headers, if any, via + * **skb_store_bytes**\ () and to recompute the checksums with + * **bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ + * (). The main case for this helper is to perform NAT64 + * operations out of an eBPF program. + * + * Internally, the GSO type is marked as dodgy so that headers are + * checked and segments are recalculated by the GSO/GRO engine. + * The size for GSO target is adapted as well. + * + * All values for *flags* are reserved for future usage, and must + * be left at zero. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_change_proto)(struct __sk_buff *skb, __be16 proto, __u64 flags) = (void *) 31; + +/* + * bpf_skb_change_type + * + * Change the packet type for the packet associated to *skb*. This + * comes down to setting *skb*\ **->pkt_type** to *type*, except + * the eBPF program does not have a write access to *skb*\ + * **->pkt_type** beside this helper. Using a helper here allows + * for graceful handling of errors. + * + * The major use case is to change incoming *skb*s to + * **PACKET_HOST** in a programmatic way instead of having to + * recirculate via **redirect**\ (..., **BPF_F_INGRESS**), for + * example. + * + * Note that *type* only allows certain values. At this time, they + * are: + * + * **PACKET_HOST** + * Packet is for us. + * **PACKET_BROADCAST** + * Send packet to all. + * **PACKET_MULTICAST** + * Send packet to group. + * **PACKET_OTHERHOST** + * Send packet to someone else. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_change_type)(struct __sk_buff *skb, __u32 type) = (void *) 32; + +/* + * bpf_skb_under_cgroup + * + * Check whether *skb* is a descendant of the cgroup2 held by + * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*. + * + * Returns + * The return value depends on the result of the test, and can be: + * + * * 0, if the *skb* failed the cgroup2 descendant test. + * * 1, if the *skb* succeeded the cgroup2 descendant test. + * * A negative error code, if an error occurred. + */ +static long (*bpf_skb_under_cgroup)(struct __sk_buff *skb, void *map, __u32 index) = (void *) 33; + +/* + * bpf_get_hash_recalc + * + * Retrieve the hash of the packet, *skb*\ **->hash**. If it is + * not set, in particular if the hash was cleared due to mangling, + * recompute this hash. Later accesses to the hash can be done + * directly with *skb*\ **->hash**. + * + * Calling **bpf_set_hash_invalid**\ (), changing a packet + * prototype with **bpf_skb_change_proto**\ (), or calling + * **bpf_skb_store_bytes**\ () with the + * **BPF_F_INVALIDATE_HASH** are actions susceptible to clear + * the hash and to trigger a new computation for the next call to + * **bpf_get_hash_recalc**\ (). + * + * Returns + * The 32-bit hash. + */ +static __u32 (*bpf_get_hash_recalc)(struct __sk_buff *skb) = (void *) 34; + +/* + * bpf_get_current_task + * + * + * Returns + * A pointer to the current task struct. + */ +static __u64 (*bpf_get_current_task)(void) = (void *) 35; + +/* + * bpf_probe_write_user + * + * Attempt in a safe way to write *len* bytes from the buffer + * *src* to *dst* in memory. It only works for threads that are in + * user context, and *dst* must be a valid user space address. + * + * This helper should not be used to implement any kind of + * security mechanism because of TOC-TOU attacks, but rather to + * debug, divert, and manipulate execution of semi-cooperative + * processes. + * + * Keep in mind that this feature is meant for experiments, and it + * has a risk of crashing the system and running programs. + * Therefore, when an eBPF program using this helper is attached, + * a warning including PID and process name is printed to kernel + * logs. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_probe_write_user)(void *dst, const void *src, __u32 len) = (void *) 36; + +/* + * bpf_current_task_under_cgroup + * + * Check whether the probe is being run is the context of a given + * subset of the cgroup2 hierarchy. The cgroup2 to test is held by + * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*. + * + * Returns + * The return value depends on the result of the test, and can be: + * + * * 0, if current task belongs to the cgroup2. + * * 1, if current task does not belong to the cgroup2. + * * A negative error code, if an error occurred. + */ +static long (*bpf_current_task_under_cgroup)(void *map, __u32 index) = (void *) 37; + +/* + * bpf_skb_change_tail + * + * Resize (trim or grow) the packet associated to *skb* to the + * new *len*. The *flags* are reserved for future usage, and must + * be left at zero. + * + * The basic idea is that the helper performs the needed work to + * change the size of the packet, then the eBPF program rewrites + * the rest via helpers like **bpf_skb_store_bytes**\ (), + * **bpf_l3_csum_replace**\ (), **bpf_l3_csum_replace**\ () + * and others. This helper is a slow path utility intended for + * replies with control messages. And because it is targeted for + * slow path, the helper itself can afford to be slow: it + * implicitly linearizes, unclones and drops offloads from the + * *skb*. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_change_tail)(struct __sk_buff *skb, __u32 len, __u64 flags) = (void *) 38; + +/* + * bpf_skb_pull_data + * + * Pull in non-linear data in case the *skb* is non-linear and not + * all of *len* are part of the linear section. Make *len* bytes + * from *skb* readable and writable. If a zero value is passed for + * *len*, then the whole length of the *skb* is pulled. + * + * This helper is only needed for reading and writing with direct + * packet access. + * + * For direct packet access, testing that offsets to access + * are within packet boundaries (test on *skb*\ **->data_end**) is + * susceptible to fail if offsets are invalid, or if the requested + * data is in non-linear parts of the *skb*. On failure the + * program can just bail out, or in the case of a non-linear + * buffer, use a helper to make the data available. The + * **bpf_skb_load_bytes**\ () helper is a first solution to access + * the data. Another one consists in using **bpf_skb_pull_data** + * to pull in once the non-linear parts, then retesting and + * eventually access the data. + * + * At the same time, this also makes sure the *skb* is uncloned, + * which is a necessary condition for direct write. As this needs + * to be an invariant for the write part only, the verifier + * detects writes and adds a prologue that is calling + * **bpf_skb_pull_data()** to effectively unclone the *skb* from + * the very beginning in case it is indeed cloned. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_pull_data)(struct __sk_buff *skb, __u32 len) = (void *) 39; + +/* + * bpf_csum_update + * + * Add the checksum *csum* into *skb*\ **->csum** in case the + * driver has supplied a checksum for the entire packet into that + * field. Return an error otherwise. This helper is intended to be + * used in combination with **bpf_csum_diff**\ (), in particular + * when the checksum needs to be updated after data has been + * written into the packet through direct packet access. + * + * Returns + * The checksum on success, or a negative error code in case of + * failure. + */ +static __s64 (*bpf_csum_update)(struct __sk_buff *skb, __wsum csum) = (void *) 40; + +/* + * bpf_set_hash_invalid + * + * Invalidate the current *skb*\ **->hash**. It can be used after + * mangling on headers through direct packet access, in order to + * indicate that the hash is outdated and to trigger a + * recalculation the next time the kernel tries to access this + * hash or when the **bpf_get_hash_recalc**\ () helper is called. + * + */ +static void (*bpf_set_hash_invalid)(struct __sk_buff *skb) = (void *) 41; + +/* + * bpf_get_numa_node_id + * + * Return the id of the current NUMA node. The primary use case + * for this helper is the selection of sockets for the local NUMA + * node, when the program is attached to sockets using the + * **SO_ATTACH_REUSEPORT_EBPF** option (see also **socket(7)**), + * but the helper is also available to other eBPF program types, + * similarly to **bpf_get_smp_processor_id**\ (). + * + * Returns + * The id of current NUMA node. + */ +static long (*bpf_get_numa_node_id)(void) = (void *) 42; + +/* + * bpf_skb_change_head + * + * Grows headroom of packet associated to *skb* and adjusts the + * offset of the MAC header accordingly, adding *len* bytes of + * space. It automatically extends and reallocates memory as + * required. + * + * This helper can be used on a layer 3 *skb* to push a MAC header + * for redirection into a layer 2 device. + * + * All values for *flags* are reserved for future usage, and must + * be left at zero. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_change_head)(struct __sk_buff *skb, __u32 len, __u64 flags) = (void *) 43; + +/* + * bpf_xdp_adjust_head + * + * Adjust (move) *xdp_md*\ **->data** by *delta* bytes. Note that + * it is possible to use a negative value for *delta*. This helper + * can be used to prepare the packet for pushing or popping + * headers. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_xdp_adjust_head)(struct xdp_md *xdp_md, int delta) = (void *) 44; + +/* + * bpf_probe_read_str + * + * Copy a NUL terminated string from an unsafe kernel address + * *unsafe_ptr* to *dst*. See **bpf_probe_read_kernel_str**\ () for + * more details. + * + * Generally, use **bpf_probe_read_user_str**\ () or + * **bpf_probe_read_kernel_str**\ () instead. + * + * Returns + * On success, the strictly positive length of the string, + * including the trailing NUL character. On error, a negative + * value. + */ +static long (*bpf_probe_read_str)(void *dst, __u32 size, const void *unsafe_ptr) = (void *) 45; + +/* + * bpf_get_socket_cookie + * + * If the **struct sk_buff** pointed by *skb* has a known socket, + * retrieve the cookie (generated by the kernel) of this socket. + * If no cookie has been set yet, generate a new cookie. Once + * generated, the socket cookie remains stable for the life of the + * socket. This helper can be useful for monitoring per socket + * networking traffic statistics as it provides a global socket + * identifier that can be assumed unique. + * + * Returns + * A 8-byte long unique number on success, or 0 if the socket + * field is missing inside *skb*. + */ +static __u64 (*bpf_get_socket_cookie)(void *ctx) = (void *) 46; + +/* + * bpf_get_socket_uid + * + * + * Returns + * The owner UID of the socket associated to *skb*. If the socket + * is **NULL**, or if it is not a full socket (i.e. if it is a + * time-wait or a request socket instead), **overflowuid** value + * is returned (note that **overflowuid** might also be the actual + * UID value for the socket). + */ +static __u32 (*bpf_get_socket_uid)(struct __sk_buff *skb) = (void *) 47; + +/* + * bpf_set_hash + * + * Set the full hash for *skb* (set the field *skb*\ **->hash**) + * to value *hash*. + * + * Returns + * 0 + */ +static long (*bpf_set_hash)(struct __sk_buff *skb, __u32 hash) = (void *) 48; + +/* + * bpf_setsockopt + * + * Emulate a call to **setsockopt()** on the socket associated to + * *bpf_socket*, which must be a full socket. The *level* at + * which the option resides and the name *optname* of the option + * must be specified, see **setsockopt(2)** for more information. + * The option value of length *optlen* is pointed by *optval*. + * + * *bpf_socket* should be one of the following: + * + * * **struct bpf_sock_ops** for **BPF_PROG_TYPE_SOCK_OPS**. + * * **struct bpf_sock_addr** for **BPF_CGROUP_INET4_CONNECT** + * and **BPF_CGROUP_INET6_CONNECT**. + * + * This helper actually implements a subset of **setsockopt()**. + * It supports the following *level*\ s: + * + * * **SOL_SOCKET**, which supports the following *optname*\ s: + * **SO_RCVBUF**, **SO_SNDBUF**, **SO_MAX_PACING_RATE**, + * **SO_PRIORITY**, **SO_RCVLOWAT**, **SO_MARK**, + * **SO_BINDTODEVICE**, **SO_KEEPALIVE**. + * * **IPPROTO_TCP**, which supports the following *optname*\ s: + * **TCP_CONGESTION**, **TCP_BPF_IW**, + * **TCP_BPF_SNDCWND_CLAMP**, **TCP_SAVE_SYN**, + * **TCP_KEEPIDLE**, **TCP_KEEPINTVL**, **TCP_KEEPCNT**, + * **TCP_SYNCNT**, **TCP_USER_TIMEOUT**, **TCP_NOTSENT_LOWAT**. + * * **IPPROTO_IP**, which supports *optname* **IP_TOS**. + * * **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_setsockopt)(void *bpf_socket, int level, int optname, void *optval, int optlen) = (void *) 49; + +/* + * bpf_skb_adjust_room + * + * Grow or shrink the room for data in the packet associated to + * *skb* by *len_diff*, and according to the selected *mode*. + * + * By default, the helper will reset any offloaded checksum + * indicator of the skb to CHECKSUM_NONE. This can be avoided + * by the following flag: + * + * * **BPF_F_ADJ_ROOM_NO_CSUM_RESET**: Do not reset offloaded + * checksum data of the skb to CHECKSUM_NONE. + * + * There are two supported modes at this time: + * + * * **BPF_ADJ_ROOM_MAC**: Adjust room at the mac layer + * (room space is added or removed below the layer 2 header). + * + * * **BPF_ADJ_ROOM_NET**: Adjust room at the network layer + * (room space is added or removed below the layer 3 header). + * + * The following flags are supported at this time: + * + * * **BPF_F_ADJ_ROOM_FIXED_GSO**: Do not adjust gso_size. + * Adjusting mss in this way is not allowed for datagrams. + * + * * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV4**, + * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV6**: + * Any new space is reserved to hold a tunnel header. + * Configure skb offsets and other fields accordingly. + * + * * **BPF_F_ADJ_ROOM_ENCAP_L4_GRE**, + * **BPF_F_ADJ_ROOM_ENCAP_L4_UDP**: + * Use with ENCAP_L3 flags to further specify the tunnel type. + * + * * **BPF_F_ADJ_ROOM_ENCAP_L2**\ (*len*): + * Use with ENCAP_L3/L4 flags to further specify the tunnel + * type; *len* is the length of the inner MAC header. + * + * * **BPF_F_ADJ_ROOM_ENCAP_L2_ETH**: + * Use with BPF_F_ADJ_ROOM_ENCAP_L2 flag to further specify the + * L2 type as Ethernet. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_adjust_room)(struct __sk_buff *skb, __s32 len_diff, __u32 mode, __u64 flags) = (void *) 50; + +/* + * bpf_redirect_map + * + * Redirect the packet to the endpoint referenced by *map* at + * index *key*. Depending on its type, this *map* can contain + * references to net devices (for forwarding packets through other + * ports), or to CPUs (for redirecting XDP frames to another CPU; + * but this is only implemented for native XDP (with driver + * support) as of this writing). + * + * The lower two bits of *flags* are used as the return code if + * the map lookup fails. This is so that the return value can be + * one of the XDP program return codes up to **XDP_TX**, as chosen + * by the caller. The higher bits of *flags* can be set to + * BPF_F_BROADCAST or BPF_F_EXCLUDE_INGRESS as defined below. + * + * With BPF_F_BROADCAST the packet will be broadcasted to all the + * interfaces in the map, with BPF_F_EXCLUDE_INGRESS the ingress + * interface will be excluded when do broadcasting. + * + * See also **bpf_redirect**\ (), which only supports redirecting + * to an ifindex, but doesn't require a map to do so. + * + * Returns + * **XDP_REDIRECT** on success, or the value of the two lower bits + * of the *flags* argument on error. + */ +static long (*bpf_redirect_map)(void *map, __u32 key, __u64 flags) = (void *) 51; + +/* + * bpf_sk_redirect_map + * + * Redirect the packet to the socket referenced by *map* (of type + * **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and + * egress interfaces can be used for redirection. The + * **BPF_F_INGRESS** value in *flags* is used to make the + * distinction (ingress path is selected if the flag is present, + * egress path otherwise). This is the only flag supported for now. + * + * Returns + * **SK_PASS** on success, or **SK_DROP** on error. + */ +static long (*bpf_sk_redirect_map)(struct __sk_buff *skb, void *map, __u32 key, __u64 flags) = (void *) 52; + +/* + * bpf_sock_map_update + * + * Add an entry to, or update a *map* referencing sockets. The + * *skops* is used as a new value for the entry associated to + * *key*. *flags* is one of: + * + * **BPF_NOEXIST** + * The entry for *key* must not exist in the map. + * **BPF_EXIST** + * The entry for *key* must already exist in the map. + * **BPF_ANY** + * No condition on the existence of the entry for *key*. + * + * If the *map* has eBPF programs (parser and verdict), those will + * be inherited by the socket being added. If the socket is + * already attached to eBPF programs, this results in an error. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_sock_map_update)(struct bpf_sock_ops *skops, void *map, void *key, __u64 flags) = (void *) 53; + +/* + * bpf_xdp_adjust_meta + * + * Adjust the address pointed by *xdp_md*\ **->data_meta** by + * *delta* (which can be positive or negative). Note that this + * operation modifies the address stored in *xdp_md*\ **->data**, + * so the latter must be loaded only after the helper has been + * called. + * + * The use of *xdp_md*\ **->data_meta** is optional and programs + * are not required to use it. The rationale is that when the + * packet is processed with XDP (e.g. as DoS filter), it is + * possible to push further meta data along with it before passing + * to the stack, and to give the guarantee that an ingress eBPF + * program attached as a TC classifier on the same device can pick + * this up for further post-processing. Since TC works with socket + * buffers, it remains possible to set from XDP the **mark** or + * **priority** pointers, or other pointers for the socket buffer. + * Having this scratch space generic and programmable allows for + * more flexibility as the user is free to store whatever meta + * data they need. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_xdp_adjust_meta)(struct xdp_md *xdp_md, int delta) = (void *) 54; + +/* + * bpf_perf_event_read_value + * + * Read the value of a perf event counter, and store it into *buf* + * of size *buf_size*. This helper relies on a *map* of type + * **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of the perf event + * counter is selected when *map* is updated with perf event file + * descriptors. The *map* is an array whose size is the number of + * available CPUs, and each cell contains a value relative to one + * CPU. The value to retrieve is indicated by *flags*, that + * contains the index of the CPU to look up, masked with + * **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to + * **BPF_F_CURRENT_CPU** to indicate that the value for the + * current CPU should be retrieved. + * + * This helper behaves in a way close to + * **bpf_perf_event_read**\ () helper, save that instead of + * just returning the value observed, it fills the *buf* + * structure. This allows for additional data to be retrieved: in + * particular, the enabled and running times (in *buf*\ + * **->enabled** and *buf*\ **->running**, respectively) are + * copied. In general, **bpf_perf_event_read_value**\ () is + * recommended over **bpf_perf_event_read**\ (), which has some + * ABI issues and provides fewer functionalities. + * + * These values are interesting, because hardware PMU (Performance + * Monitoring Unit) counters are limited resources. When there are + * more PMU based perf events opened than available counters, + * kernel will multiplex these events so each event gets certain + * percentage (but not all) of the PMU time. In case that + * multiplexing happens, the number of samples or counter value + * will not reflect the case compared to when no multiplexing + * occurs. This makes comparison between different runs difficult. + * Typically, the counter value should be normalized before + * comparing to other experiments. The usual normalization is done + * as follows. + * + * :: + * + * normalized_counter = counter * t_enabled / t_running + * + * Where t_enabled is the time enabled for event and t_running is + * the time running for event since last normalization. The + * enabled and running times are accumulated since the perf event + * open. To achieve scaling factor between two invocations of an + * eBPF program, users can use CPU id as the key (which is + * typical for perf array usage model) to remember the previous + * value and do the calculation inside the eBPF program. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_perf_event_read_value)(void *map, __u64 flags, struct bpf_perf_event_value *buf, __u32 buf_size) = (void *) 55; + +/* + * bpf_perf_prog_read_value + * + * For en eBPF program attached to a perf event, retrieve the + * value of the event counter associated to *ctx* and store it in + * the structure pointed by *buf* and of size *buf_size*. Enabled + * and running times are also stored in the structure (see + * description of helper **bpf_perf_event_read_value**\ () for + * more details). + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_perf_prog_read_value)(struct bpf_perf_event_data *ctx, struct bpf_perf_event_value *buf, __u32 buf_size) = (void *) 56; + +/* + * bpf_getsockopt + * + * Emulate a call to **getsockopt()** on the socket associated to + * *bpf_socket*, which must be a full socket. The *level* at + * which the option resides and the name *optname* of the option + * must be specified, see **getsockopt(2)** for more information. + * The retrieved value is stored in the structure pointed by + * *opval* and of length *optlen*. + * + * *bpf_socket* should be one of the following: + * + * * **struct bpf_sock_ops** for **BPF_PROG_TYPE_SOCK_OPS**. + * * **struct bpf_sock_addr** for **BPF_CGROUP_INET4_CONNECT** + * and **BPF_CGROUP_INET6_CONNECT**. + * + * This helper actually implements a subset of **getsockopt()**. + * It supports the following *level*\ s: + * + * * **IPPROTO_TCP**, which supports *optname* + * **TCP_CONGESTION**. + * * **IPPROTO_IP**, which supports *optname* **IP_TOS**. + * * **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_getsockopt)(void *bpf_socket, int level, int optname, void *optval, int optlen) = (void *) 57; + +/* + * bpf_override_return + * + * Used for error injection, this helper uses kprobes to override + * the return value of the probed function, and to set it to *rc*. + * The first argument is the context *regs* on which the kprobe + * works. + * + * This helper works by setting the PC (program counter) + * to an override function which is run in place of the original + * probed function. This means the probed function is not run at + * all. The replacement function just returns with the required + * value. + * + * This helper has security implications, and thus is subject to + * restrictions. It is only available if the kernel was compiled + * with the **CONFIG_BPF_KPROBE_OVERRIDE** configuration + * option, and in this case it only works on functions tagged with + * **ALLOW_ERROR_INJECTION** in the kernel code. + * + * Also, the helper is only available for the architectures having + * the CONFIG_FUNCTION_ERROR_INJECTION option. As of this writing, + * x86 architecture is the only one to support this feature. + * + * Returns + * 0 + */ +static long (*bpf_override_return)(struct pt_regs *regs, __u64 rc) = (void *) 58; + +/* + * bpf_sock_ops_cb_flags_set + * + * Attempt to set the value of the **bpf_sock_ops_cb_flags** field + * for the full TCP socket associated to *bpf_sock_ops* to + * *argval*. + * + * The primary use of this field is to determine if there should + * be calls to eBPF programs of type + * **BPF_PROG_TYPE_SOCK_OPS** at various points in the TCP + * code. A program of the same type can change its value, per + * connection and as necessary, when the connection is + * established. This field is directly accessible for reading, but + * this helper must be used for updates in order to return an + * error if an eBPF program tries to set a callback that is not + * supported in the current kernel. + * + * *argval* is a flag array which can combine these flags: + * + * * **BPF_SOCK_OPS_RTO_CB_FLAG** (retransmission time out) + * * **BPF_SOCK_OPS_RETRANS_CB_FLAG** (retransmission) + * * **BPF_SOCK_OPS_STATE_CB_FLAG** (TCP state change) + * * **BPF_SOCK_OPS_RTT_CB_FLAG** (every RTT) + * + * Therefore, this function can be used to clear a callback flag by + * setting the appropriate bit to zero. e.g. to disable the RTO + * callback: + * + * **bpf_sock_ops_cb_flags_set(bpf_sock,** + * **bpf_sock->bpf_sock_ops_cb_flags & ~BPF_SOCK_OPS_RTO_CB_FLAG)** + * + * Here are some examples of where one could call such eBPF + * program: + * + * * When RTO fires. + * * When a packet is retransmitted. + * * When the connection terminates. + * * When a packet is sent. + * * When a packet is received. + * + * Returns + * Code **-EINVAL** if the socket is not a full TCP socket; + * otherwise, a positive number containing the bits that could not + * be set is returned (which comes down to 0 if all bits were set + * as required). + */ +static long (*bpf_sock_ops_cb_flags_set)(struct bpf_sock_ops *bpf_sock, int argval) = (void *) 59; + +/* + * bpf_msg_redirect_map + * + * This helper is used in programs implementing policies at the + * socket level. If the message *msg* is allowed to pass (i.e. if + * the verdict eBPF program returns **SK_PASS**), redirect it to + * the socket referenced by *map* (of type + * **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and + * egress interfaces can be used for redirection. The + * **BPF_F_INGRESS** value in *flags* is used to make the + * distinction (ingress path is selected if the flag is present, + * egress path otherwise). This is the only flag supported for now. + * + * Returns + * **SK_PASS** on success, or **SK_DROP** on error. + */ +static long (*bpf_msg_redirect_map)(struct sk_msg_md *msg, void *map, __u32 key, __u64 flags) = (void *) 60; + +/* + * bpf_msg_apply_bytes + * + * For socket policies, apply the verdict of the eBPF program to + * the next *bytes* (number of bytes) of message *msg*. + * + * For example, this helper can be used in the following cases: + * + * * A single **sendmsg**\ () or **sendfile**\ () system call + * contains multiple logical messages that the eBPF program is + * supposed to read and for which it should apply a verdict. + * * An eBPF program only cares to read the first *bytes* of a + * *msg*. If the message has a large payload, then setting up + * and calling the eBPF program repeatedly for all bytes, even + * though the verdict is already known, would create unnecessary + * overhead. + * + * When called from within an eBPF program, the helper sets a + * counter internal to the BPF infrastructure, that is used to + * apply the last verdict to the next *bytes*. If *bytes* is + * smaller than the current data being processed from a + * **sendmsg**\ () or **sendfile**\ () system call, the first + * *bytes* will be sent and the eBPF program will be re-run with + * the pointer for start of data pointing to byte number *bytes* + * **+ 1**. If *bytes* is larger than the current data being + * processed, then the eBPF verdict will be applied to multiple + * **sendmsg**\ () or **sendfile**\ () calls until *bytes* are + * consumed. + * + * Note that if a socket closes with the internal counter holding + * a non-zero value, this is not a problem because data is not + * being buffered for *bytes* and is sent as it is received. + * + * Returns + * 0 + */ +static long (*bpf_msg_apply_bytes)(struct sk_msg_md *msg, __u32 bytes) = (void *) 61; + +/* + * bpf_msg_cork_bytes + * + * For socket policies, prevent the execution of the verdict eBPF + * program for message *msg* until *bytes* (byte number) have been + * accumulated. + * + * This can be used when one needs a specific number of bytes + * before a verdict can be assigned, even if the data spans + * multiple **sendmsg**\ () or **sendfile**\ () calls. The extreme + * case would be a user calling **sendmsg**\ () repeatedly with + * 1-byte long message segments. Obviously, this is bad for + * performance, but it is still valid. If the eBPF program needs + * *bytes* bytes to validate a header, this helper can be used to + * prevent the eBPF program to be called again until *bytes* have + * been accumulated. + * + * Returns + * 0 + */ +static long (*bpf_msg_cork_bytes)(struct sk_msg_md *msg, __u32 bytes) = (void *) 62; + +/* + * bpf_msg_pull_data + * + * For socket policies, pull in non-linear data from user space + * for *msg* and set pointers *msg*\ **->data** and *msg*\ + * **->data_end** to *start* and *end* bytes offsets into *msg*, + * respectively. + * + * If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a + * *msg* it can only parse data that the (**data**, **data_end**) + * pointers have already consumed. For **sendmsg**\ () hooks this + * is likely the first scatterlist element. But for calls relying + * on the **sendpage** handler (e.g. **sendfile**\ ()) this will + * be the range (**0**, **0**) because the data is shared with + * user space and by default the objective is to avoid allowing + * user space to modify data while (or after) eBPF verdict is + * being decided. This helper can be used to pull in data and to + * set the start and end pointer to given values. Data will be + * copied if necessary (i.e. if data was not linear and if start + * and end pointers do not point to the same chunk). + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * All values for *flags* are reserved for future usage, and must + * be left at zero. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_msg_pull_data)(struct sk_msg_md *msg, __u32 start, __u32 end, __u64 flags) = (void *) 63; + +/* + * bpf_bind + * + * Bind the socket associated to *ctx* to the address pointed by + * *addr*, of length *addr_len*. This allows for making outgoing + * connection from the desired IP address, which can be useful for + * example when all processes inside a cgroup should use one + * single IP address on a host that has multiple IP configured. + * + * This helper works for IPv4 and IPv6, TCP and UDP sockets. The + * domain (*addr*\ **->sa_family**) must be **AF_INET** (or + * **AF_INET6**). It's advised to pass zero port (**sin_port** + * or **sin6_port**) which triggers IP_BIND_ADDRESS_NO_PORT-like + * behavior and lets the kernel efficiently pick up an unused + * port as long as 4-tuple is unique. Passing non-zero port might + * lead to degraded performance. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_bind)(struct bpf_sock_addr *ctx, struct sockaddr *addr, int addr_len) = (void *) 64; + +/* + * bpf_xdp_adjust_tail + * + * Adjust (move) *xdp_md*\ **->data_end** by *delta* bytes. It is + * possible to both shrink and grow the packet tail. + * Shrink done via *delta* being a negative integer. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_xdp_adjust_tail)(struct xdp_md *xdp_md, int delta) = (void *) 65; + +/* + * bpf_skb_get_xfrm_state + * + * Retrieve the XFRM state (IP transform framework, see also + * **ip-xfrm(8)**) at *index* in XFRM "security path" for *skb*. + * + * The retrieved value is stored in the **struct bpf_xfrm_state** + * pointed by *xfrm_state* and of length *size*. + * + * All values for *flags* are reserved for future usage, and must + * be left at zero. + * + * This helper is available only if the kernel was compiled with + * **CONFIG_XFRM** configuration option. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_get_xfrm_state)(struct __sk_buff *skb, __u32 index, struct bpf_xfrm_state *xfrm_state, __u32 size, __u64 flags) = (void *) 66; + +/* + * bpf_get_stack + * + * Return a user or a kernel stack in bpf program provided buffer. + * To achieve this, the helper needs *ctx*, which is a pointer + * to the context on which the tracing program is executed. + * To store the stacktrace, the bpf program provides *buf* with + * a nonnegative *size*. + * + * The last argument, *flags*, holds the number of stack frames to + * skip (from 0 to 255), masked with + * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set + * the following flags: + * + * **BPF_F_USER_STACK** + * Collect a user space stack instead of a kernel stack. + * **BPF_F_USER_BUILD_ID** + * Collect buildid+offset instead of ips for user stack, + * only valid if **BPF_F_USER_STACK** is also specified. + * + * **bpf_get_stack**\ () can collect up to + * **PERF_MAX_STACK_DEPTH** both kernel and user frames, subject + * to sufficient large buffer size. Note that + * this limit can be controlled with the **sysctl** program, and + * that it should be manually increased in order to profile long + * user stacks (such as stacks for Java programs). To do so, use: + * + * :: + * + * # sysctl kernel.perf_event_max_stack= + * + * Returns + * A non-negative value equal to or less than *size* on success, + * or a negative error in case of failure. + */ +static long (*bpf_get_stack)(void *ctx, void *buf, __u32 size, __u64 flags) = (void *) 67; + +/* + * bpf_skb_load_bytes_relative + * + * This helper is similar to **bpf_skb_load_bytes**\ () in that + * it provides an easy way to load *len* bytes from *offset* + * from the packet associated to *skb*, into the buffer pointed + * by *to*. The difference to **bpf_skb_load_bytes**\ () is that + * a fifth argument *start_header* exists in order to select a + * base offset to start from. *start_header* can be one of: + * + * **BPF_HDR_START_MAC** + * Base offset to load data from is *skb*'s mac header. + * **BPF_HDR_START_NET** + * Base offset to load data from is *skb*'s network header. + * + * In general, "direct packet access" is the preferred method to + * access packet data, however, this helper is in particular useful + * in socket filters where *skb*\ **->data** does not always point + * to the start of the mac header and where "direct packet access" + * is not available. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_load_bytes_relative)(const void *skb, __u32 offset, void *to, __u32 len, __u32 start_header) = (void *) 68; + +/* + * bpf_fib_lookup + * + * Do FIB lookup in kernel tables using parameters in *params*. + * If lookup is successful and result shows packet is to be + * forwarded, the neighbor tables are searched for the nexthop. + * If successful (ie., FIB lookup shows forwarding and nexthop + * is resolved), the nexthop address is returned in ipv4_dst + * or ipv6_dst based on family, smac is set to mac address of + * egress device, dmac is set to nexthop mac address, rt_metric + * is set to metric from route (IPv4/IPv6 only), and ifindex + * is set to the device index of the nexthop from the FIB lookup. + * + * *plen* argument is the size of the passed in struct. + * *flags* argument can be a combination of one or more of the + * following values: + * + * **BPF_FIB_LOOKUP_DIRECT** + * Do a direct table lookup vs full lookup using FIB + * rules. + * **BPF_FIB_LOOKUP_OUTPUT** + * Perform lookup from an egress perspective (default is + * ingress). + * + * *ctx* is either **struct xdp_md** for XDP programs or + * **struct sk_buff** tc cls_act programs. + * + * Returns + * * < 0 if any input argument is invalid + * * 0 on success (packet is forwarded, nexthop neighbor exists) + * * > 0 one of **BPF_FIB_LKUP_RET_** codes explaining why the + * packet is not forwarded or needs assist from full stack + * + * If lookup fails with BPF_FIB_LKUP_RET_FRAG_NEEDED, then the MTU + * was exceeded and output params->mtu_result contains the MTU. + */ +static long (*bpf_fib_lookup)(void *ctx, struct bpf_fib_lookup *params, int plen, __u32 flags) = (void *) 69; + +/* + * bpf_sock_hash_update + * + * Add an entry to, or update a sockhash *map* referencing sockets. + * The *skops* is used as a new value for the entry associated to + * *key*. *flags* is one of: + * + * **BPF_NOEXIST** + * The entry for *key* must not exist in the map. + * **BPF_EXIST** + * The entry for *key* must already exist in the map. + * **BPF_ANY** + * No condition on the existence of the entry for *key*. + * + * If the *map* has eBPF programs (parser and verdict), those will + * be inherited by the socket being added. If the socket is + * already attached to eBPF programs, this results in an error. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_sock_hash_update)(struct bpf_sock_ops *skops, void *map, void *key, __u64 flags) = (void *) 70; + +/* + * bpf_msg_redirect_hash + * + * This helper is used in programs implementing policies at the + * socket level. If the message *msg* is allowed to pass (i.e. if + * the verdict eBPF program returns **SK_PASS**), redirect it to + * the socket referenced by *map* (of type + * **BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and + * egress interfaces can be used for redirection. The + * **BPF_F_INGRESS** value in *flags* is used to make the + * distinction (ingress path is selected if the flag is present, + * egress path otherwise). This is the only flag supported for now. + * + * Returns + * **SK_PASS** on success, or **SK_DROP** on error. + */ +static long (*bpf_msg_redirect_hash)(struct sk_msg_md *msg, void *map, void *key, __u64 flags) = (void *) 71; + +/* + * bpf_sk_redirect_hash + * + * This helper is used in programs implementing policies at the + * skb socket level. If the sk_buff *skb* is allowed to pass (i.e. + * if the verdict eBPF program returns **SK_PASS**), redirect it + * to the socket referenced by *map* (of type + * **BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and + * egress interfaces can be used for redirection. The + * **BPF_F_INGRESS** value in *flags* is used to make the + * distinction (ingress path is selected if the flag is present, + * egress otherwise). This is the only flag supported for now. + * + * Returns + * **SK_PASS** on success, or **SK_DROP** on error. + */ +static long (*bpf_sk_redirect_hash)(struct __sk_buff *skb, void *map, void *key, __u64 flags) = (void *) 72; + +/* + * bpf_lwt_push_encap + * + * Encapsulate the packet associated to *skb* within a Layer 3 + * protocol header. This header is provided in the buffer at + * address *hdr*, with *len* its size in bytes. *type* indicates + * the protocol of the header and can be one of: + * + * **BPF_LWT_ENCAP_SEG6** + * IPv6 encapsulation with Segment Routing Header + * (**struct ipv6_sr_hdr**). *hdr* only contains the SRH, + * the IPv6 header is computed by the kernel. + * **BPF_LWT_ENCAP_SEG6_INLINE** + * Only works if *skb* contains an IPv6 packet. Insert a + * Segment Routing Header (**struct ipv6_sr_hdr**) inside + * the IPv6 header. + * **BPF_LWT_ENCAP_IP** + * IP encapsulation (GRE/GUE/IPIP/etc). The outer header + * must be IPv4 or IPv6, followed by zero or more + * additional headers, up to **LWT_BPF_MAX_HEADROOM** + * total bytes in all prepended headers. Please note that + * if **skb_is_gso**\ (*skb*) is true, no more than two + * headers can be prepended, and the inner header, if + * present, should be either GRE or UDP/GUE. + * + * **BPF_LWT_ENCAP_SEG6**\ \* types can be called by BPF programs + * of type **BPF_PROG_TYPE_LWT_IN**; **BPF_LWT_ENCAP_IP** type can + * be called by bpf programs of types **BPF_PROG_TYPE_LWT_IN** and + * **BPF_PROG_TYPE_LWT_XMIT**. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_lwt_push_encap)(struct __sk_buff *skb, __u32 type, void *hdr, __u32 len) = (void *) 73; + +/* + * bpf_lwt_seg6_store_bytes + * + * Store *len* bytes from address *from* into the packet + * associated to *skb*, at *offset*. Only the flags, tag and TLVs + * inside the outermost IPv6 Segment Routing Header can be + * modified through this helper. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_lwt_seg6_store_bytes)(struct __sk_buff *skb, __u32 offset, const void *from, __u32 len) = (void *) 74; + +/* + * bpf_lwt_seg6_adjust_srh + * + * Adjust the size allocated to TLVs in the outermost IPv6 + * Segment Routing Header contained in the packet associated to + * *skb*, at position *offset* by *delta* bytes. Only offsets + * after the segments are accepted. *delta* can be as well + * positive (growing) as negative (shrinking). + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_lwt_seg6_adjust_srh)(struct __sk_buff *skb, __u32 offset, __s32 delta) = (void *) 75; + +/* + * bpf_lwt_seg6_action + * + * Apply an IPv6 Segment Routing action of type *action* to the + * packet associated to *skb*. Each action takes a parameter + * contained at address *param*, and of length *param_len* bytes. + * *action* can be one of: + * + * **SEG6_LOCAL_ACTION_END_X** + * End.X action: Endpoint with Layer-3 cross-connect. + * Type of *param*: **struct in6_addr**. + * **SEG6_LOCAL_ACTION_END_T** + * End.T action: Endpoint with specific IPv6 table lookup. + * Type of *param*: **int**. + * **SEG6_LOCAL_ACTION_END_B6** + * End.B6 action: Endpoint bound to an SRv6 policy. + * Type of *param*: **struct ipv6_sr_hdr**. + * **SEG6_LOCAL_ACTION_END_B6_ENCAP** + * End.B6.Encap action: Endpoint bound to an SRv6 + * encapsulation policy. + * Type of *param*: **struct ipv6_sr_hdr**. + * + * A call to this helper is susceptible to change the underlying + * packet buffer. Therefore, at load time, all checks on pointers + * previously done by the verifier are invalidated and must be + * performed again, if the helper is used in combination with + * direct packet access. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_lwt_seg6_action)(struct __sk_buff *skb, __u32 action, void *param, __u32 param_len) = (void *) 76; + +/* + * bpf_rc_repeat + * + * This helper is used in programs implementing IR decoding, to + * report a successfully decoded repeat key message. This delays + * the generation of a key up event for previously generated + * key down event. + * + * Some IR protocols like NEC have a special IR message for + * repeating last button, for when a button is held down. + * + * The *ctx* should point to the lirc sample as passed into + * the program. + * + * This helper is only available is the kernel was compiled with + * the **CONFIG_BPF_LIRC_MODE2** configuration option set to + * "**y**". + * + * Returns + * 0 + */ +static long (*bpf_rc_repeat)(void *ctx) = (void *) 77; + +/* + * bpf_rc_keydown + * + * This helper is used in programs implementing IR decoding, to + * report a successfully decoded key press with *scancode*, + * *toggle* value in the given *protocol*. The scancode will be + * translated to a keycode using the rc keymap, and reported as + * an input key down event. After a period a key up event is + * generated. This period can be extended by calling either + * **bpf_rc_keydown**\ () again with the same values, or calling + * **bpf_rc_repeat**\ (). + * + * Some protocols include a toggle bit, in case the button was + * released and pressed again between consecutive scancodes. + * + * The *ctx* should point to the lirc sample as passed into + * the program. + * + * The *protocol* is the decoded protocol number (see + * **enum rc_proto** for some predefined values). + * + * This helper is only available is the kernel was compiled with + * the **CONFIG_BPF_LIRC_MODE2** configuration option set to + * "**y**". + * + * Returns + * 0 + */ +static long (*bpf_rc_keydown)(void *ctx, __u32 protocol, __u64 scancode, __u32 toggle) = (void *) 78; + +/* + * bpf_skb_cgroup_id + * + * Return the cgroup v2 id of the socket associated with the *skb*. + * This is roughly similar to the **bpf_get_cgroup_classid**\ () + * helper for cgroup v1 by providing a tag resp. identifier that + * can be matched on or used for map lookups e.g. to implement + * policy. The cgroup v2 id of a given path in the hierarchy is + * exposed in user space through the f_handle API in order to get + * to the same 64-bit id. + * + * This helper can be used on TC egress path, but not on ingress, + * and is available only if the kernel was compiled with the + * **CONFIG_SOCK_CGROUP_DATA** configuration option. + * + * Returns + * The id is returned or 0 in case the id could not be retrieved. + */ +static __u64 (*bpf_skb_cgroup_id)(struct __sk_buff *skb) = (void *) 79; + +/* + * bpf_get_current_cgroup_id + * + * + * Returns + * A 64-bit integer containing the current cgroup id based + * on the cgroup within which the current task is running. + */ +static __u64 (*bpf_get_current_cgroup_id)(void) = (void *) 80; + +/* + * bpf_get_local_storage + * + * Get the pointer to the local storage area. + * The type and the size of the local storage is defined + * by the *map* argument. + * The *flags* meaning is specific for each map type, + * and has to be 0 for cgroup local storage. + * + * Depending on the BPF program type, a local storage area + * can be shared between multiple instances of the BPF program, + * running simultaneously. + * + * A user should care about the synchronization by himself. + * For example, by using the **BPF_ATOMIC** instructions to alter + * the shared data. + * + * Returns + * A pointer to the local storage area. + */ +static void *(*bpf_get_local_storage)(void *map, __u64 flags) = (void *) 81; + +/* + * bpf_sk_select_reuseport + * + * Select a **SO_REUSEPORT** socket from a + * **BPF_MAP_TYPE_REUSEPORT_SOCKARRAY** *map*. + * It checks the selected socket is matching the incoming + * request in the socket buffer. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_sk_select_reuseport)(struct sk_reuseport_md *reuse, void *map, void *key, __u64 flags) = (void *) 82; + +/* + * bpf_skb_ancestor_cgroup_id + * + * Return id of cgroup v2 that is ancestor of cgroup associated + * with the *skb* at the *ancestor_level*. The root cgroup is at + * *ancestor_level* zero and each step down the hierarchy + * increments the level. If *ancestor_level* == level of cgroup + * associated with *skb*, then return value will be same as that + * of **bpf_skb_cgroup_id**\ (). + * + * The helper is useful to implement policies based on cgroups + * that are upper in hierarchy than immediate cgroup associated + * with *skb*. + * + * The format of returned id and helper limitations are same as in + * **bpf_skb_cgroup_id**\ (). + * + * Returns + * The id is returned or 0 in case the id could not be retrieved. + */ +static __u64 (*bpf_skb_ancestor_cgroup_id)(struct __sk_buff *skb, int ancestor_level) = (void *) 83; + +/* + * bpf_sk_lookup_tcp + * + * Look for TCP socket matching *tuple*, optionally in a child + * network namespace *netns*. The return value must be checked, + * and if non-**NULL**, released via **bpf_sk_release**\ (). + * + * The *ctx* should point to the context of the program, such as + * the skb or socket (depending on the hook in use). This is used + * to determine the base network namespace for the lookup. + * + * *tuple_size* must be one of: + * + * **sizeof**\ (*tuple*\ **->ipv4**) + * Look for an IPv4 socket. + * **sizeof**\ (*tuple*\ **->ipv6**) + * Look for an IPv6 socket. + * + * If the *netns* is a negative signed 32-bit integer, then the + * socket lookup table in the netns associated with the *ctx* + * will be used. For the TC hooks, this is the netns of the device + * in the skb. For socket hooks, this is the netns of the socket. + * If *netns* is any other signed 32-bit value greater than or + * equal to zero then it specifies the ID of the netns relative to + * the netns associated with the *ctx*. *netns* values beyond the + * range of 32-bit integers are reserved for future use. + * + * All values for *flags* are reserved for future usage, and must + * be left at zero. + * + * This helper is available only if the kernel was compiled with + * **CONFIG_NET** configuration option. + * + * Returns + * Pointer to **struct bpf_sock**, or **NULL** in case of failure. + * For sockets with reuseport option, the **struct bpf_sock** + * result is from *reuse*\ **->socks**\ [] using the hash of the + * tuple. + */ +static struct bpf_sock *(*bpf_sk_lookup_tcp)(void *ctx, struct bpf_sock_tuple *tuple, __u32 tuple_size, __u64 netns, __u64 flags) = (void *) 84; + +/* + * bpf_sk_lookup_udp + * + * Look for UDP socket matching *tuple*, optionally in a child + * network namespace *netns*. The return value must be checked, + * and if non-**NULL**, released via **bpf_sk_release**\ (). + * + * The *ctx* should point to the context of the program, such as + * the skb or socket (depending on the hook in use). This is used + * to determine the base network namespace for the lookup. + * + * *tuple_size* must be one of: + * + * **sizeof**\ (*tuple*\ **->ipv4**) + * Look for an IPv4 socket. + * **sizeof**\ (*tuple*\ **->ipv6**) + * Look for an IPv6 socket. + * + * If the *netns* is a negative signed 32-bit integer, then the + * socket lookup table in the netns associated with the *ctx* + * will be used. For the TC hooks, this is the netns of the device + * in the skb. For socket hooks, this is the netns of the socket. + * If *netns* is any other signed 32-bit value greater than or + * equal to zero then it specifies the ID of the netns relative to + * the netns associated with the *ctx*. *netns* values beyond the + * range of 32-bit integers are reserved for future use. + * + * All values for *flags* are reserved for future usage, and must + * be left at zero. + * + * This helper is available only if the kernel was compiled with + * **CONFIG_NET** configuration option. + * + * Returns + * Pointer to **struct bpf_sock**, or **NULL** in case of failure. + * For sockets with reuseport option, the **struct bpf_sock** + * result is from *reuse*\ **->socks**\ [] using the hash of the + * tuple. + */ +static struct bpf_sock *(*bpf_sk_lookup_udp)(void *ctx, struct bpf_sock_tuple *tuple, __u32 tuple_size, __u64 netns, __u64 flags) = (void *) 85; + +/* + * bpf_sk_release + * + * Release the reference held by *sock*. *sock* must be a + * non-**NULL** pointer that was returned from + * **bpf_sk_lookup_xxx**\ (). + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_sk_release)(void *sock) = (void *) 86; + +/* + * bpf_map_push_elem + * + * Push an element *value* in *map*. *flags* is one of: + * + * **BPF_EXIST** + * If the queue/stack is full, the oldest element is + * removed to make room for this. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_map_push_elem)(void *map, const void *value, __u64 flags) = (void *) 87; + +/* + * bpf_map_pop_elem + * + * Pop an element from *map*. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_map_pop_elem)(void *map, void *value) = (void *) 88; + +/* + * bpf_map_peek_elem + * + * Get an element from *map* without removing it. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_map_peek_elem)(void *map, void *value) = (void *) 89; + +/* + * bpf_msg_push_data + * + * For socket policies, insert *len* bytes into *msg* at offset + * *start*. + * + * If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a + * *msg* it may want to insert metadata or options into the *msg*. + * This can later be read and used by any of the lower layer BPF + * hooks. + * + * This helper may fail if under memory pressure (a malloc + * fails) in these cases BPF programs will get an appropriate + * error and BPF programs will need to handle them. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_msg_push_data)(struct sk_msg_md *msg, __u32 start, __u32 len, __u64 flags) = (void *) 90; + +/* + * bpf_msg_pop_data + * + * Will remove *len* bytes from a *msg* starting at byte *start*. + * This may result in **ENOMEM** errors under certain situations if + * an allocation and copy are required due to a full ring buffer. + * However, the helper will try to avoid doing the allocation + * if possible. Other errors can occur if input parameters are + * invalid either due to *start* byte not being valid part of *msg* + * payload and/or *pop* value being to large. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_msg_pop_data)(struct sk_msg_md *msg, __u32 start, __u32 len, __u64 flags) = (void *) 91; + +/* + * bpf_rc_pointer_rel + * + * This helper is used in programs implementing IR decoding, to + * report a successfully decoded pointer movement. + * + * The *ctx* should point to the lirc sample as passed into + * the program. + * + * This helper is only available is the kernel was compiled with + * the **CONFIG_BPF_LIRC_MODE2** configuration option set to + * "**y**". + * + * Returns + * 0 + */ +static long (*bpf_rc_pointer_rel)(void *ctx, __s32 rel_x, __s32 rel_y) = (void *) 92; + +/* + * bpf_spin_lock + * + * Acquire a spinlock represented by the pointer *lock*, which is + * stored as part of a value of a map. Taking the lock allows to + * safely update the rest of the fields in that value. The + * spinlock can (and must) later be released with a call to + * **bpf_spin_unlock**\ (\ *lock*\ ). + * + * Spinlocks in BPF programs come with a number of restrictions + * and constraints: + * + * * **bpf_spin_lock** objects are only allowed inside maps of + * types **BPF_MAP_TYPE_HASH** and **BPF_MAP_TYPE_ARRAY** (this + * list could be extended in the future). + * * BTF description of the map is mandatory. + * * The BPF program can take ONE lock at a time, since taking two + * or more could cause dead locks. + * * Only one **struct bpf_spin_lock** is allowed per map element. + * * When the lock is taken, calls (either BPF to BPF or helpers) + * are not allowed. + * * The **BPF_LD_ABS** and **BPF_LD_IND** instructions are not + * allowed inside a spinlock-ed region. + * * The BPF program MUST call **bpf_spin_unlock**\ () to release + * the lock, on all execution paths, before it returns. + * * The BPF program can access **struct bpf_spin_lock** only via + * the **bpf_spin_lock**\ () and **bpf_spin_unlock**\ () + * helpers. Loading or storing data into the **struct + * bpf_spin_lock** *lock*\ **;** field of a map is not allowed. + * * To use the **bpf_spin_lock**\ () helper, the BTF description + * of the map value must be a struct and have **struct + * bpf_spin_lock** *anyname*\ **;** field at the top level. + * Nested lock inside another struct is not allowed. + * * The **struct bpf_spin_lock** *lock* field in a map value must + * be aligned on a multiple of 4 bytes in that value. + * * Syscall with command **BPF_MAP_LOOKUP_ELEM** does not copy + * the **bpf_spin_lock** field to user space. + * * Syscall with command **BPF_MAP_UPDATE_ELEM**, or update from + * a BPF program, do not update the **bpf_spin_lock** field. + * * **bpf_spin_lock** cannot be on the stack or inside a + * networking packet (it can only be inside of a map values). + * * **bpf_spin_lock** is available to root only. + * * Tracing programs and socket filter programs cannot use + * **bpf_spin_lock**\ () due to insufficient preemption checks + * (but this may change in the future). + * * **bpf_spin_lock** is not allowed in inner maps of map-in-map. + * + * Returns + * 0 + */ +static long (*bpf_spin_lock)(struct bpf_spin_lock *lock) = (void *) 93; + +/* + * bpf_spin_unlock + * + * Release the *lock* previously locked by a call to + * **bpf_spin_lock**\ (\ *lock*\ ). + * + * Returns + * 0 + */ +static long (*bpf_spin_unlock)(struct bpf_spin_lock *lock) = (void *) 94; + +/* + * bpf_sk_fullsock + * + * This helper gets a **struct bpf_sock** pointer such + * that all the fields in this **bpf_sock** can be accessed. + * + * Returns + * A **struct bpf_sock** pointer on success, or **NULL** in + * case of failure. + */ +static struct bpf_sock *(*bpf_sk_fullsock)(struct bpf_sock *sk) = (void *) 95; + +/* + * bpf_tcp_sock + * + * This helper gets a **struct bpf_tcp_sock** pointer from a + * **struct bpf_sock** pointer. + * + * Returns + * A **struct bpf_tcp_sock** pointer on success, or **NULL** in + * case of failure. + */ +static struct bpf_tcp_sock *(*bpf_tcp_sock)(struct bpf_sock *sk) = (void *) 96; + +/* + * bpf_skb_ecn_set_ce + * + * Set ECN (Explicit Congestion Notification) field of IP header + * to **CE** (Congestion Encountered) if current value is **ECT** + * (ECN Capable Transport). Otherwise, do nothing. Works with IPv6 + * and IPv4. + * + * Returns + * 1 if the **CE** flag is set (either by the current helper call + * or because it was already present), 0 if it is not set. + */ +static long (*bpf_skb_ecn_set_ce)(struct __sk_buff *skb) = (void *) 97; + +/* + * bpf_get_listener_sock + * + * Return a **struct bpf_sock** pointer in **TCP_LISTEN** state. + * **bpf_sk_release**\ () is unnecessary and not allowed. + * + * Returns + * A **struct bpf_sock** pointer on success, or **NULL** in + * case of failure. + */ +static struct bpf_sock *(*bpf_get_listener_sock)(struct bpf_sock *sk) = (void *) 98; + +/* + * bpf_skc_lookup_tcp + * + * Look for TCP socket matching *tuple*, optionally in a child + * network namespace *netns*. The return value must be checked, + * and if non-**NULL**, released via **bpf_sk_release**\ (). + * + * This function is identical to **bpf_sk_lookup_tcp**\ (), except + * that it also returns timewait or request sockets. Use + * **bpf_sk_fullsock**\ () or **bpf_tcp_sock**\ () to access the + * full structure. + * + * This helper is available only if the kernel was compiled with + * **CONFIG_NET** configuration option. + * + * Returns + * Pointer to **struct bpf_sock**, or **NULL** in case of failure. + * For sockets with reuseport option, the **struct bpf_sock** + * result is from *reuse*\ **->socks**\ [] using the hash of the + * tuple. + */ +static struct bpf_sock *(*bpf_skc_lookup_tcp)(void *ctx, struct bpf_sock_tuple *tuple, __u32 tuple_size, __u64 netns, __u64 flags) = (void *) 99; + +/* + * bpf_tcp_check_syncookie + * + * Check whether *iph* and *th* contain a valid SYN cookie ACK for + * the listening socket in *sk*. + * + * *iph* points to the start of the IPv4 or IPv6 header, while + * *iph_len* contains **sizeof**\ (**struct iphdr**) or + * **sizeof**\ (**struct ip6hdr**). + * + * *th* points to the start of the TCP header, while *th_len* + * contains **sizeof**\ (**struct tcphdr**). + * + * Returns + * 0 if *iph* and *th* are a valid SYN cookie ACK, or a negative + * error otherwise. + */ +static long (*bpf_tcp_check_syncookie)(void *sk, void *iph, __u32 iph_len, struct tcphdr *th, __u32 th_len) = (void *) 100; + +/* + * bpf_sysctl_get_name + * + * Get name of sysctl in /proc/sys/ and copy it into provided by + * program buffer *buf* of size *buf_len*. + * + * The buffer is always NUL terminated, unless it's zero-sized. + * + * If *flags* is zero, full name (e.g. "net/ipv4/tcp_mem") is + * copied. Use **BPF_F_SYSCTL_BASE_NAME** flag to copy base name + * only (e.g. "tcp_mem"). + * + * Returns + * Number of character copied (not including the trailing NUL). + * + * **-E2BIG** if the buffer wasn't big enough (*buf* will contain + * truncated name in this case). + */ +static long (*bpf_sysctl_get_name)(struct bpf_sysctl *ctx, char *buf, unsigned long buf_len, __u64 flags) = (void *) 101; + +/* + * bpf_sysctl_get_current_value + * + * Get current value of sysctl as it is presented in /proc/sys + * (incl. newline, etc), and copy it as a string into provided + * by program buffer *buf* of size *buf_len*. + * + * The whole value is copied, no matter what file position user + * space issued e.g. sys_read at. + * + * The buffer is always NUL terminated, unless it's zero-sized. + * + * Returns + * Number of character copied (not including the trailing NUL). + * + * **-E2BIG** if the buffer wasn't big enough (*buf* will contain + * truncated name in this case). + * + * **-EINVAL** if current value was unavailable, e.g. because + * sysctl is uninitialized and read returns -EIO for it. + */ +static long (*bpf_sysctl_get_current_value)(struct bpf_sysctl *ctx, char *buf, unsigned long buf_len) = (void *) 102; + +/* + * bpf_sysctl_get_new_value + * + * Get new value being written by user space to sysctl (before + * the actual write happens) and copy it as a string into + * provided by program buffer *buf* of size *buf_len*. + * + * User space may write new value at file position > 0. + * + * The buffer is always NUL terminated, unless it's zero-sized. + * + * Returns + * Number of character copied (not including the trailing NUL). + * + * **-E2BIG** if the buffer wasn't big enough (*buf* will contain + * truncated name in this case). + * + * **-EINVAL** if sysctl is being read. + */ +static long (*bpf_sysctl_get_new_value)(struct bpf_sysctl *ctx, char *buf, unsigned long buf_len) = (void *) 103; + +/* + * bpf_sysctl_set_new_value + * + * Override new value being written by user space to sysctl with + * value provided by program in buffer *buf* of size *buf_len*. + * + * *buf* should contain a string in same form as provided by user + * space on sysctl write. + * + * User space may write new value at file position > 0. To override + * the whole sysctl value file position should be set to zero. + * + * Returns + * 0 on success. + * + * **-E2BIG** if the *buf_len* is too big. + * + * **-EINVAL** if sysctl is being read. + */ +static long (*bpf_sysctl_set_new_value)(struct bpf_sysctl *ctx, const char *buf, unsigned long buf_len) = (void *) 104; + +/* + * bpf_strtol + * + * Convert the initial part of the string from buffer *buf* of + * size *buf_len* to a long integer according to the given base + * and save the result in *res*. + * + * The string may begin with an arbitrary amount of white space + * (as determined by **isspace**\ (3)) followed by a single + * optional '**-**' sign. + * + * Five least significant bits of *flags* encode base, other bits + * are currently unused. + * + * Base must be either 8, 10, 16 or 0 to detect it automatically + * similar to user space **strtol**\ (3). + * + * Returns + * Number of characters consumed on success. Must be positive but + * no more than *buf_len*. + * + * **-EINVAL** if no valid digits were found or unsupported base + * was provided. + * + * **-ERANGE** if resulting value was out of range. + */ +static long (*bpf_strtol)(const char *buf, unsigned long buf_len, __u64 flags, long *res) = (void *) 105; + +/* + * bpf_strtoul + * + * Convert the initial part of the string from buffer *buf* of + * size *buf_len* to an unsigned long integer according to the + * given base and save the result in *res*. + * + * The string may begin with an arbitrary amount of white space + * (as determined by **isspace**\ (3)). + * + * Five least significant bits of *flags* encode base, other bits + * are currently unused. + * + * Base must be either 8, 10, 16 or 0 to detect it automatically + * similar to user space **strtoul**\ (3). + * + * Returns + * Number of characters consumed on success. Must be positive but + * no more than *buf_len*. + * + * **-EINVAL** if no valid digits were found or unsupported base + * was provided. + * + * **-ERANGE** if resulting value was out of range. + */ +static long (*bpf_strtoul)(const char *buf, unsigned long buf_len, __u64 flags, unsigned long *res) = (void *) 106; + +/* + * bpf_sk_storage_get + * + * Get a bpf-local-storage from a *sk*. + * + * Logically, it could be thought of getting the value from + * a *map* with *sk* as the **key**. From this + * perspective, the usage is not much different from + * **bpf_map_lookup_elem**\ (*map*, **&**\ *sk*) except this + * helper enforces the key must be a full socket and the map must + * be a **BPF_MAP_TYPE_SK_STORAGE** also. + * + * Underneath, the value is stored locally at *sk* instead of + * the *map*. The *map* is used as the bpf-local-storage + * "type". The bpf-local-storage "type" (i.e. the *map*) is + * searched against all bpf-local-storages residing at *sk*. + * + * *sk* is a kernel **struct sock** pointer for LSM program. + * *sk* is a **struct bpf_sock** pointer for other program types. + * + * An optional *flags* (**BPF_SK_STORAGE_GET_F_CREATE**) can be + * used such that a new bpf-local-storage will be + * created if one does not exist. *value* can be used + * together with **BPF_SK_STORAGE_GET_F_CREATE** to specify + * the initial value of a bpf-local-storage. If *value* is + * **NULL**, the new bpf-local-storage will be zero initialized. + * + * Returns + * A bpf-local-storage pointer is returned on success. + * + * **NULL** if not found or there was an error in adding + * a new bpf-local-storage. + */ +static void *(*bpf_sk_storage_get)(void *map, void *sk, void *value, __u64 flags) = (void *) 107; + +/* + * bpf_sk_storage_delete + * + * Delete a bpf-local-storage from a *sk*. + * + * Returns + * 0 on success. + * + * **-ENOENT** if the bpf-local-storage cannot be found. + * **-EINVAL** if sk is not a fullsock (e.g. a request_sock). + */ +static long (*bpf_sk_storage_delete)(void *map, void *sk) = (void *) 108; + +/* + * bpf_send_signal + * + * Send signal *sig* to the process of the current task. + * The signal may be delivered to any of this process's threads. + * + * Returns + * 0 on success or successfully queued. + * + * **-EBUSY** if work queue under nmi is full. + * + * **-EINVAL** if *sig* is invalid. + * + * **-EPERM** if no permission to send the *sig*. + * + * **-EAGAIN** if bpf program can try again. + */ +static long (*bpf_send_signal)(__u32 sig) = (void *) 109; + +/* + * bpf_tcp_gen_syncookie + * + * Try to issue a SYN cookie for the packet with corresponding + * IP/TCP headers, *iph* and *th*, on the listening socket in *sk*. + * + * *iph* points to the start of the IPv4 or IPv6 header, while + * *iph_len* contains **sizeof**\ (**struct iphdr**) or + * **sizeof**\ (**struct ip6hdr**). + * + * *th* points to the start of the TCP header, while *th_len* + * contains the length of the TCP header. + * + * Returns + * On success, lower 32 bits hold the generated SYN cookie in + * followed by 16 bits which hold the MSS value for that cookie, + * and the top 16 bits are unused. + * + * On failure, the returned value is one of the following: + * + * **-EINVAL** SYN cookie cannot be issued due to error + * + * **-ENOENT** SYN cookie should not be issued (no SYN flood) + * + * **-EOPNOTSUPP** kernel configuration does not enable SYN cookies + * + * **-EPROTONOSUPPORT** IP packet version is not 4 or 6 + */ +static __s64 (*bpf_tcp_gen_syncookie)(void *sk, void *iph, __u32 iph_len, struct tcphdr *th, __u32 th_len) = (void *) 110; + +/* + * bpf_skb_output + * + * Write raw *data* blob into a special BPF perf event held by + * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf + * event must have the following attributes: **PERF_SAMPLE_RAW** + * as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and + * **PERF_COUNT_SW_BPF_OUTPUT** as **config**. + * + * The *flags* are used to indicate the index in *map* for which + * the value must be put, masked with **BPF_F_INDEX_MASK**. + * Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU** + * to indicate that the index of the current CPU core should be + * used. + * + * The value to write, of *size*, is passed through eBPF stack and + * pointed by *data*. + * + * *ctx* is a pointer to in-kernel struct sk_buff. + * + * This helper is similar to **bpf_perf_event_output**\ () but + * restricted to raw_tracepoint bpf programs. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_skb_output)(void *ctx, void *map, __u64 flags, void *data, __u64 size) = (void *) 111; + +/* + * bpf_probe_read_user + * + * Safely attempt to read *size* bytes from user space address + * *unsafe_ptr* and store the data in *dst*. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_probe_read_user)(void *dst, __u32 size, const void *unsafe_ptr) = (void *) 112; + +/* + * bpf_probe_read_kernel + * + * Safely attempt to read *size* bytes from kernel space address + * *unsafe_ptr* and store the data in *dst*. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_probe_read_kernel)(void *dst, __u32 size, const void *unsafe_ptr) = (void *) 113; + +/* + * bpf_probe_read_user_str + * + * Copy a NUL terminated string from an unsafe user address + * *unsafe_ptr* to *dst*. The *size* should include the + * terminating NUL byte. In case the string length is smaller than + * *size*, the target is not padded with further NUL bytes. If the + * string length is larger than *size*, just *size*-1 bytes are + * copied and the last byte is set to NUL. + * + * On success, returns the number of bytes that were written, + * including the terminal NUL. This makes this helper useful in + * tracing programs for reading strings, and more importantly to + * get its length at runtime. See the following snippet: + * + * :: + * + * SEC("kprobe/sys_open") + * void bpf_sys_open(struct pt_regs *ctx) + * { + * char buf[PATHLEN]; // PATHLEN is defined to 256 + * int res = bpf_probe_read_user_str(buf, sizeof(buf), + * ctx->di); + * + * // Consume buf, for example push it to + * // userspace via bpf_perf_event_output(); we + * // can use res (the string length) as event + * // size, after checking its boundaries. + * } + * + * In comparison, using **bpf_probe_read_user**\ () helper here + * instead to read the string would require to estimate the length + * at compile time, and would often result in copying more memory + * than necessary. + * + * Another useful use case is when parsing individual process + * arguments or individual environment variables navigating + * *current*\ **->mm->arg_start** and *current*\ + * **->mm->env_start**: using this helper and the return value, + * one can quickly iterate at the right offset of the memory area. + * + * Returns + * On success, the strictly positive length of the output string, + * including the trailing NUL character. On error, a negative + * value. + */ +static long (*bpf_probe_read_user_str)(void *dst, __u32 size, const void *unsafe_ptr) = (void *) 114; + +/* + * bpf_probe_read_kernel_str + * + * Copy a NUL terminated string from an unsafe kernel address *unsafe_ptr* + * to *dst*. Same semantics as with **bpf_probe_read_user_str**\ () apply. + * + * Returns + * On success, the strictly positive length of the string, including + * the trailing NUL character. On error, a negative value. + */ +static long (*bpf_probe_read_kernel_str)(void *dst, __u32 size, const void *unsafe_ptr) = (void *) 115; + +/* + * bpf_tcp_send_ack + * + * Send out a tcp-ack. *tp* is the in-kernel struct **tcp_sock**. + * *rcv_nxt* is the ack_seq to be sent out. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_tcp_send_ack)(void *tp, __u32 rcv_nxt) = (void *) 116; + +/* + * bpf_send_signal_thread + * + * Send signal *sig* to the thread corresponding to the current task. + * + * Returns + * 0 on success or successfully queued. + * + * **-EBUSY** if work queue under nmi is full. + * + * **-EINVAL** if *sig* is invalid. + * + * **-EPERM** if no permission to send the *sig*. + * + * **-EAGAIN** if bpf program can try again. + */ +static long (*bpf_send_signal_thread)(__u32 sig) = (void *) 117; + +/* + * bpf_jiffies64 + * + * Obtain the 64bit jiffies + * + * Returns + * The 64 bit jiffies + */ +static __u64 (*bpf_jiffies64)(void) = (void *) 118; + +/* + * bpf_read_branch_records + * + * For an eBPF program attached to a perf event, retrieve the + * branch records (**struct perf_branch_entry**) associated to *ctx* + * and store it in the buffer pointed by *buf* up to size + * *size* bytes. + * + * Returns + * On success, number of bytes written to *buf*. On error, a + * negative value. + * + * The *flags* can be set to **BPF_F_GET_BRANCH_RECORDS_SIZE** to + * instead return the number of bytes required to store all the + * branch entries. If this flag is set, *buf* may be NULL. + * + * **-EINVAL** if arguments invalid or **size** not a multiple + * of **sizeof**\ (**struct perf_branch_entry**\ ). + * + * **-ENOENT** if architecture does not support branch records. + */ +static long (*bpf_read_branch_records)(struct bpf_perf_event_data *ctx, void *buf, __u32 size, __u64 flags) = (void *) 119; + +/* + * bpf_get_ns_current_pid_tgid + * + * Returns 0 on success, values for *pid* and *tgid* as seen from the current + * *namespace* will be returned in *nsdata*. + * + * Returns + * 0 on success, or one of the following in case of failure: + * + * **-EINVAL** if dev and inum supplied don't match dev_t and inode number + * with nsfs of current task, or if dev conversion to dev_t lost high bits. + * + * **-ENOENT** if pidns does not exists for the current task. + */ +static long (*bpf_get_ns_current_pid_tgid)(__u64 dev, __u64 ino, struct bpf_pidns_info *nsdata, __u32 size) = (void *) 120; + +/* + * bpf_xdp_output + * + * Write raw *data* blob into a special BPF perf event held by + * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf + * event must have the following attributes: **PERF_SAMPLE_RAW** + * as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and + * **PERF_COUNT_SW_BPF_OUTPUT** as **config**. + * + * The *flags* are used to indicate the index in *map* for which + * the value must be put, masked with **BPF_F_INDEX_MASK**. + * Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU** + * to indicate that the index of the current CPU core should be + * used. + * + * The value to write, of *size*, is passed through eBPF stack and + * pointed by *data*. + * + * *ctx* is a pointer to in-kernel struct xdp_buff. + * + * This helper is similar to **bpf_perf_eventoutput**\ () but + * restricted to raw_tracepoint bpf programs. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_xdp_output)(void *ctx, void *map, __u64 flags, void *data, __u64 size) = (void *) 121; + +/* + * bpf_get_netns_cookie + * + * Retrieve the cookie (generated by the kernel) of the network + * namespace the input *ctx* is associated with. The network + * namespace cookie remains stable for its lifetime and provides + * a global identifier that can be assumed unique. If *ctx* is + * NULL, then the helper returns the cookie for the initial + * network namespace. The cookie itself is very similar to that + * of **bpf_get_socket_cookie**\ () helper, but for network + * namespaces instead of sockets. + * + * Returns + * A 8-byte long opaque number. + */ +static __u64 (*bpf_get_netns_cookie)(void *ctx) = (void *) 122; + +/* + * bpf_get_current_ancestor_cgroup_id + * + * Return id of cgroup v2 that is ancestor of the cgroup associated + * with the current task at the *ancestor_level*. The root cgroup + * is at *ancestor_level* zero and each step down the hierarchy + * increments the level. If *ancestor_level* == level of cgroup + * associated with the current task, then return value will be the + * same as that of **bpf_get_current_cgroup_id**\ (). + * + * The helper is useful to implement policies based on cgroups + * that are upper in hierarchy than immediate cgroup associated + * with the current task. + * + * The format of returned id and helper limitations are same as in + * **bpf_get_current_cgroup_id**\ (). + * + * Returns + * The id is returned or 0 in case the id could not be retrieved. + */ +static __u64 (*bpf_get_current_ancestor_cgroup_id)(int ancestor_level) = (void *) 123; + +/* + * bpf_sk_assign + * + * Helper is overloaded depending on BPF program type. This + * description applies to **BPF_PROG_TYPE_SCHED_CLS** and + * **BPF_PROG_TYPE_SCHED_ACT** programs. + * + * Assign the *sk* to the *skb*. When combined with appropriate + * routing configuration to receive the packet towards the socket, + * will cause *skb* to be delivered to the specified socket. + * Subsequent redirection of *skb* via **bpf_redirect**\ (), + * **bpf_clone_redirect**\ () or other methods outside of BPF may + * interfere with successful delivery to the socket. + * + * This operation is only valid from TC ingress path. + * + * The *flags* argument must be zero. + * + * Returns + * 0 on success, or a negative error in case of failure: + * + * **-EINVAL** if specified *flags* are not supported. + * + * **-ENOENT** if the socket is unavailable for assignment. + * + * **-ENETUNREACH** if the socket is unreachable (wrong netns). + * + * **-EOPNOTSUPP** if the operation is not supported, for example + * a call from outside of TC ingress. + * + * **-ESOCKTNOSUPPORT** if the socket type is not supported + * (reuseport). + */ +static long (*bpf_sk_assign)(void *ctx, void *sk, __u64 flags) = (void *) 124; + +/* + * bpf_ktime_get_boot_ns + * + * Return the time elapsed since system boot, in nanoseconds. + * Does include the time the system was suspended. + * See: **clock_gettime**\ (**CLOCK_BOOTTIME**) + * + * Returns + * Current *ktime*. + */ +static __u64 (*bpf_ktime_get_boot_ns)(void) = (void *) 125; + +/* + * bpf_seq_printf + * + * **bpf_seq_printf**\ () uses seq_file **seq_printf**\ () to print + * out the format string. + * The *m* represents the seq_file. The *fmt* and *fmt_size* are for + * the format string itself. The *data* and *data_len* are format string + * arguments. The *data* are a **u64** array and corresponding format string + * values are stored in the array. For strings and pointers where pointees + * are accessed, only the pointer values are stored in the *data* array. + * The *data_len* is the size of *data* in bytes - must be a multiple of 8. + * + * Formats **%s**, **%p{i,I}{4,6}** requires to read kernel memory. + * Reading kernel memory may fail due to either invalid address or + * valid address but requiring a major memory fault. If reading kernel memory + * fails, the string for **%s** will be an empty string, and the ip + * address for **%p{i,I}{4,6}** will be 0. Not returning error to + * bpf program is consistent with what **bpf_trace_printk**\ () does for now. + * + * Returns + * 0 on success, or a negative error in case of failure: + * + * **-EBUSY** if per-CPU memory copy buffer is busy, can try again + * by returning 1 from bpf program. + * + * **-EINVAL** if arguments are invalid, or if *fmt* is invalid/unsupported. + * + * **-E2BIG** if *fmt* contains too many format specifiers. + * + * **-EOVERFLOW** if an overflow happened: The same object will be tried again. + */ +static long (*bpf_seq_printf)(struct seq_file *m, const char *fmt, __u32 fmt_size, const void *data, __u32 data_len) = (void *) 126; + +/* + * bpf_seq_write + * + * **bpf_seq_write**\ () uses seq_file **seq_write**\ () to write the data. + * The *m* represents the seq_file. The *data* and *len* represent the + * data to write in bytes. + * + * Returns + * 0 on success, or a negative error in case of failure: + * + * **-EOVERFLOW** if an overflow happened: The same object will be tried again. + */ +static long (*bpf_seq_write)(struct seq_file *m, const void *data, __u32 len) = (void *) 127; + +/* + * bpf_sk_cgroup_id + * + * Return the cgroup v2 id of the socket *sk*. + * + * *sk* must be a non-**NULL** pointer to a socket, e.g. one + * returned from **bpf_sk_lookup_xxx**\ (), + * **bpf_sk_fullsock**\ (), etc. The format of returned id is + * same as in **bpf_skb_cgroup_id**\ (). + * + * This helper is available only if the kernel was compiled with + * the **CONFIG_SOCK_CGROUP_DATA** configuration option. + * + * Returns + * The id is returned or 0 in case the id could not be retrieved. + */ +static __u64 (*bpf_sk_cgroup_id)(void *sk) = (void *) 128; + +/* + * bpf_sk_ancestor_cgroup_id + * + * Return id of cgroup v2 that is ancestor of cgroup associated + * with the *sk* at the *ancestor_level*. The root cgroup is at + * *ancestor_level* zero and each step down the hierarchy + * increments the level. If *ancestor_level* == level of cgroup + * associated with *sk*, then return value will be same as that + * of **bpf_sk_cgroup_id**\ (). + * + * The helper is useful to implement policies based on cgroups + * that are upper in hierarchy than immediate cgroup associated + * with *sk*. + * + * The format of returned id and helper limitations are same as in + * **bpf_sk_cgroup_id**\ (). + * + * Returns + * The id is returned or 0 in case the id could not be retrieved. + */ +static __u64 (*bpf_sk_ancestor_cgroup_id)(void *sk, int ancestor_level) = (void *) 129; + +/* + * bpf_ringbuf_output + * + * Copy *size* bytes from *data* into a ring buffer *ringbuf*. + * If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification + * of new data availability is sent. + * If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification + * of new data availability is sent unconditionally. + * If **0** is specified in *flags*, an adaptive notification + * of new data availability is sent. + * + * An adaptive notification is a notification sent whenever the user-space + * process has caught up and consumed all available payloads. In case the user-space + * process is still processing a previous payload, then no notification is needed + * as it will process the newly added payload automatically. + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_ringbuf_output)(void *ringbuf, void *data, __u64 size, __u64 flags) = (void *) 130; + +/* + * bpf_ringbuf_reserve + * + * Reserve *size* bytes of payload in a ring buffer *ringbuf*. + * *flags* must be 0. + * + * Returns + * Valid pointer with *size* bytes of memory available; NULL, + * otherwise. + */ +static void *(*bpf_ringbuf_reserve)(void *ringbuf, __u64 size, __u64 flags) = (void *) 131; + +/* + * bpf_ringbuf_submit + * + * Submit reserved ring buffer sample, pointed to by *data*. + * If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification + * of new data availability is sent. + * If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification + * of new data availability is sent unconditionally. + * If **0** is specified in *flags*, an adaptive notification + * of new data availability is sent. + * + * See 'bpf_ringbuf_output()' for the definition of adaptive notification. + * + * Returns + * Nothing. Always succeeds. + */ +static void (*bpf_ringbuf_submit)(void *data, __u64 flags) = (void *) 132; + +/* + * bpf_ringbuf_discard + * + * Discard reserved ring buffer sample, pointed to by *data*. + * If **BPF_RB_NO_WAKEUP** is specified in *flags*, no notification + * of new data availability is sent. + * If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification + * of new data availability is sent unconditionally. + * If **0** is specified in *flags*, an adaptive notification + * of new data availability is sent. + * + * See 'bpf_ringbuf_output()' for the definition of adaptive notification. + * + * Returns + * Nothing. Always succeeds. + */ +static void (*bpf_ringbuf_discard)(void *data, __u64 flags) = (void *) 133; + +/* + * bpf_ringbuf_query + * + * Query various characteristics of provided ring buffer. What + * exactly is queries is determined by *flags*: + * + * * **BPF_RB_AVAIL_DATA**: Amount of data not yet consumed. + * * **BPF_RB_RING_SIZE**: The size of ring buffer. + * * **BPF_RB_CONS_POS**: Consumer position (can wrap around). + * * **BPF_RB_PROD_POS**: Producer(s) position (can wrap around). + * + * Data returned is just a momentary snapshot of actual values + * and could be inaccurate, so this facility should be used to + * power heuristics and for reporting, not to make 100% correct + * calculation. + * + * Returns + * Requested value, or 0, if *flags* are not recognized. + */ +static __u64 (*bpf_ringbuf_query)(void *ringbuf, __u64 flags) = (void *) 134; + +/* + * bpf_csum_level + * + * Change the skbs checksum level by one layer up or down, or + * reset it entirely to none in order to have the stack perform + * checksum validation. The level is applicable to the following + * protocols: TCP, UDP, GRE, SCTP, FCOE. For example, a decap of + * | ETH | IP | UDP | GUE | IP | TCP | into | ETH | IP | TCP | + * through **bpf_skb_adjust_room**\ () helper with passing in + * **BPF_F_ADJ_ROOM_NO_CSUM_RESET** flag would require one call + * to **bpf_csum_level**\ () with **BPF_CSUM_LEVEL_DEC** since + * the UDP header is removed. Similarly, an encap of the latter + * into the former could be accompanied by a helper call to + * **bpf_csum_level**\ () with **BPF_CSUM_LEVEL_INC** if the + * skb is still intended to be processed in higher layers of the + * stack instead of just egressing at tc. + * + * There are three supported level settings at this time: + * + * * **BPF_CSUM_LEVEL_INC**: Increases skb->csum_level for skbs + * with CHECKSUM_UNNECESSARY. + * * **BPF_CSUM_LEVEL_DEC**: Decreases skb->csum_level for skbs + * with CHECKSUM_UNNECESSARY. + * * **BPF_CSUM_LEVEL_RESET**: Resets skb->csum_level to 0 and + * sets CHECKSUM_NONE to force checksum validation by the stack. + * * **BPF_CSUM_LEVEL_QUERY**: No-op, returns the current + * skb->csum_level. + * + * Returns + * 0 on success, or a negative error in case of failure. In the + * case of **BPF_CSUM_LEVEL_QUERY**, the current skb->csum_level + * is returned or the error code -EACCES in case the skb is not + * subject to CHECKSUM_UNNECESSARY. + */ +static long (*bpf_csum_level)(struct __sk_buff *skb, __u64 level) = (void *) 135; + +/* + * bpf_skc_to_tcp6_sock + * + * Dynamically cast a *sk* pointer to a *tcp6_sock* pointer. + * + * Returns + * *sk* if casting is valid, or **NULL** otherwise. + */ +static struct tcp6_sock *(*bpf_skc_to_tcp6_sock)(void *sk) = (void *) 136; + +/* + * bpf_skc_to_tcp_sock + * + * Dynamically cast a *sk* pointer to a *tcp_sock* pointer. + * + * Returns + * *sk* if casting is valid, or **NULL** otherwise. + */ +static struct tcp_sock *(*bpf_skc_to_tcp_sock)(void *sk) = (void *) 137; + +/* + * bpf_skc_to_tcp_timewait_sock + * + * Dynamically cast a *sk* pointer to a *tcp_timewait_sock* pointer. + * + * Returns + * *sk* if casting is valid, or **NULL** otherwise. + */ +static struct tcp_timewait_sock *(*bpf_skc_to_tcp_timewait_sock)(void *sk) = (void *) 138; + +/* + * bpf_skc_to_tcp_request_sock + * + * Dynamically cast a *sk* pointer to a *tcp_request_sock* pointer. + * + * Returns + * *sk* if casting is valid, or **NULL** otherwise. + */ +static struct tcp_request_sock *(*bpf_skc_to_tcp_request_sock)(void *sk) = (void *) 139; + +/* + * bpf_skc_to_udp6_sock + * + * Dynamically cast a *sk* pointer to a *udp6_sock* pointer. + * + * Returns + * *sk* if casting is valid, or **NULL** otherwise. + */ +static struct udp6_sock *(*bpf_skc_to_udp6_sock)(void *sk) = (void *) 140; + +/* + * bpf_get_task_stack + * + * Return a user or a kernel stack in bpf program provided buffer. + * To achieve this, the helper needs *task*, which is a valid + * pointer to **struct task_struct**. To store the stacktrace, the + * bpf program provides *buf* with a nonnegative *size*. + * + * The last argument, *flags*, holds the number of stack frames to + * skip (from 0 to 255), masked with + * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set + * the following flags: + * + * **BPF_F_USER_STACK** + * Collect a user space stack instead of a kernel stack. + * **BPF_F_USER_BUILD_ID** + * Collect buildid+offset instead of ips for user stack, + * only valid if **BPF_F_USER_STACK** is also specified. + * + * **bpf_get_task_stack**\ () can collect up to + * **PERF_MAX_STACK_DEPTH** both kernel and user frames, subject + * to sufficient large buffer size. Note that + * this limit can be controlled with the **sysctl** program, and + * that it should be manually increased in order to profile long + * user stacks (such as stacks for Java programs). To do so, use: + * + * :: + * + * # sysctl kernel.perf_event_max_stack= + * + * Returns + * A non-negative value equal to or less than *size* on success, + * or a negative error in case of failure. + */ +static long (*bpf_get_task_stack)(struct task_struct *task, void *buf, __u32 size, __u64 flags) = (void *) 141; + +/* + * bpf_load_hdr_opt + * + * Load header option. Support reading a particular TCP header + * option for bpf program (**BPF_PROG_TYPE_SOCK_OPS**). + * + * If *flags* is 0, it will search the option from the + * *skops*\ **->skb_data**. The comment in **struct bpf_sock_ops** + * has details on what skb_data contains under different + * *skops*\ **->op**. + * + * The first byte of the *searchby_res* specifies the + * kind that it wants to search. + * + * If the searching kind is an experimental kind + * (i.e. 253 or 254 according to RFC6994). It also + * needs to specify the "magic" which is either + * 2 bytes or 4 bytes. It then also needs to + * specify the size of the magic by using + * the 2nd byte which is "kind-length" of a TCP + * header option and the "kind-length" also + * includes the first 2 bytes "kind" and "kind-length" + * itself as a normal TCP header option also does. + * + * For example, to search experimental kind 254 with + * 2 byte magic 0xeB9F, the searchby_res should be + * [ 254, 4, 0xeB, 0x9F, 0, 0, .... 0 ]. + * + * To search for the standard window scale option (3), + * the *searchby_res* should be [ 3, 0, 0, .... 0 ]. + * Note, kind-length must be 0 for regular option. + * + * Searching for No-Op (0) and End-of-Option-List (1) are + * not supported. + * + * *len* must be at least 2 bytes which is the minimal size + * of a header option. + * + * Supported flags: + * + * * **BPF_LOAD_HDR_OPT_TCP_SYN** to search from the + * saved_syn packet or the just-received syn packet. + * + * + * Returns + * > 0 when found, the header option is copied to *searchby_res*. + * The return value is the total length copied. On failure, a + * negative error code is returned: + * + * **-EINVAL** if a parameter is invalid. + * + * **-ENOMSG** if the option is not found. + * + * **-ENOENT** if no syn packet is available when + * **BPF_LOAD_HDR_OPT_TCP_SYN** is used. + * + * **-ENOSPC** if there is not enough space. Only *len* number of + * bytes are copied. + * + * **-EFAULT** on failure to parse the header options in the + * packet. + * + * **-EPERM** if the helper cannot be used under the current + * *skops*\ **->op**. + */ +static long (*bpf_load_hdr_opt)(struct bpf_sock_ops *skops, void *searchby_res, __u32 len, __u64 flags) = (void *) 142; + +/* + * bpf_store_hdr_opt + * + * Store header option. The data will be copied + * from buffer *from* with length *len* to the TCP header. + * + * The buffer *from* should have the whole option that + * includes the kind, kind-length, and the actual + * option data. The *len* must be at least kind-length + * long. The kind-length does not have to be 4 byte + * aligned. The kernel will take care of the padding + * and setting the 4 bytes aligned value to th->doff. + * + * This helper will check for duplicated option + * by searching the same option in the outgoing skb. + * + * This helper can only be called during + * **BPF_SOCK_OPS_WRITE_HDR_OPT_CB**. + * + * + * Returns + * 0 on success, or negative error in case of failure: + * + * **-EINVAL** If param is invalid. + * + * **-ENOSPC** if there is not enough space in the header. + * Nothing has been written + * + * **-EEXIST** if the option already exists. + * + * **-EFAULT** on failrue to parse the existing header options. + * + * **-EPERM** if the helper cannot be used under the current + * *skops*\ **->op**. + */ +static long (*bpf_store_hdr_opt)(struct bpf_sock_ops *skops, const void *from, __u32 len, __u64 flags) = (void *) 143; + +/* + * bpf_reserve_hdr_opt + * + * Reserve *len* bytes for the bpf header option. The + * space will be used by **bpf_store_hdr_opt**\ () later in + * **BPF_SOCK_OPS_WRITE_HDR_OPT_CB**. + * + * If **bpf_reserve_hdr_opt**\ () is called multiple times, + * the total number of bytes will be reserved. + * + * This helper can only be called during + * **BPF_SOCK_OPS_HDR_OPT_LEN_CB**. + * + * + * Returns + * 0 on success, or negative error in case of failure: + * + * **-EINVAL** if a parameter is invalid. + * + * **-ENOSPC** if there is not enough space in the header. + * + * **-EPERM** if the helper cannot be used under the current + * *skops*\ **->op**. + */ +static long (*bpf_reserve_hdr_opt)(struct bpf_sock_ops *skops, __u32 len, __u64 flags) = (void *) 144; + +/* + * bpf_inode_storage_get + * + * Get a bpf_local_storage from an *inode*. + * + * Logically, it could be thought of as getting the value from + * a *map* with *inode* as the **key**. From this + * perspective, the usage is not much different from + * **bpf_map_lookup_elem**\ (*map*, **&**\ *inode*) except this + * helper enforces the key must be an inode and the map must also + * be a **BPF_MAP_TYPE_INODE_STORAGE**. + * + * Underneath, the value is stored locally at *inode* instead of + * the *map*. The *map* is used as the bpf-local-storage + * "type". The bpf-local-storage "type" (i.e. the *map*) is + * searched against all bpf_local_storage residing at *inode*. + * + * An optional *flags* (**BPF_LOCAL_STORAGE_GET_F_CREATE**) can be + * used such that a new bpf_local_storage will be + * created if one does not exist. *value* can be used + * together with **BPF_LOCAL_STORAGE_GET_F_CREATE** to specify + * the initial value of a bpf_local_storage. If *value* is + * **NULL**, the new bpf_local_storage will be zero initialized. + * + * Returns + * A bpf_local_storage pointer is returned on success. + * + * **NULL** if not found or there was an error in adding + * a new bpf_local_storage. + */ +static void *(*bpf_inode_storage_get)(void *map, void *inode, void *value, __u64 flags) = (void *) 145; + +/* + * bpf_inode_storage_delete + * + * Delete a bpf_local_storage from an *inode*. + * + * Returns + * 0 on success. + * + * **-ENOENT** if the bpf_local_storage cannot be found. + */ +static int (*bpf_inode_storage_delete)(void *map, void *inode) = (void *) 146; + +/* + * bpf_d_path + * + * Return full path for given **struct path** object, which + * needs to be the kernel BTF *path* object. The path is + * returned in the provided buffer *buf* of size *sz* and + * is zero terminated. + * + * + * Returns + * On success, the strictly positive length of the string, + * including the trailing NUL character. On error, a negative + * value. + */ +static long (*bpf_d_path)(struct path *path, char *buf, __u32 sz) = (void *) 147; + +/* + * bpf_copy_from_user + * + * Read *size* bytes from user space address *user_ptr* and store + * the data in *dst*. This is a wrapper of **copy_from_user**\ (). + * + * Returns + * 0 on success, or a negative error in case of failure. + */ +static long (*bpf_copy_from_user)(void *dst, __u32 size, const void *user_ptr) = (void *) 148; + +/* + * bpf_snprintf_btf + * + * Use BTF to store a string representation of *ptr*->ptr in *str*, + * using *ptr*->type_id. This value should specify the type + * that *ptr*->ptr points to. LLVM __builtin_btf_type_id(type, 1) + * can be used to look up vmlinux BTF type ids. Traversing the + * data structure using BTF, the type information and values are + * stored in the first *str_size* - 1 bytes of *str*. Safe copy of + * the pointer data is carried out to avoid kernel crashes during + * operation. Smaller types can use string space on the stack; + * larger programs can use map data to store the string + * representation. + * + * The string can be subsequently shared with userspace via + * bpf_perf_event_output() or ring buffer interfaces. + * bpf_trace_printk() is to be avoided as it places too small + * a limit on string size to be useful. + * + * *flags* is a combination of + * + * **BTF_F_COMPACT** + * no formatting around type information + * **BTF_F_NONAME** + * no struct/union member names/types + * **BTF_F_PTR_RAW** + * show raw (unobfuscated) pointer values; + * equivalent to printk specifier %px. + * **BTF_F_ZERO** + * show zero-valued struct/union members; they + * are not displayed by default + * + * + * Returns + * The number of bytes that were written (or would have been + * written if output had to be truncated due to string size), + * or a negative error in cases of failure. + */ +static long (*bpf_snprintf_btf)(char *str, __u32 str_size, struct btf_ptr *ptr, __u32 btf_ptr_size, __u64 flags) = (void *) 149; + +/* + * bpf_seq_printf_btf + * + * Use BTF to write to seq_write a string representation of + * *ptr*->ptr, using *ptr*->type_id as per bpf_snprintf_btf(). + * *flags* are identical to those used for bpf_snprintf_btf. + * + * Returns + * 0 on success or a negative error in case of failure. + */ +static long (*bpf_seq_printf_btf)(struct seq_file *m, struct btf_ptr *ptr, __u32 ptr_size, __u64 flags) = (void *) 150; + +/* + * bpf_skb_cgroup_classid + * + * See **bpf_get_cgroup_classid**\ () for the main description. + * This helper differs from **bpf_get_cgroup_classid**\ () in that + * the cgroup v1 net_cls class is retrieved only from the *skb*'s + * associated socket instead of the current process. + * + * Returns + * The id is returned or 0 in case the id could not be retrieved. + */ +static __u64 (*bpf_skb_cgroup_classid)(struct __sk_buff *skb) = (void *) 151; + +/* + * bpf_redirect_neigh + * + * Redirect the packet to another net device of index *ifindex* + * and fill in L2 addresses from neighboring subsystem. This helper + * is somewhat similar to **bpf_redirect**\ (), except that it + * populates L2 addresses as well, meaning, internally, the helper + * relies on the neighbor lookup for the L2 address of the nexthop. + * + * The helper will perform a FIB lookup based on the skb's + * networking header to get the address of the next hop, unless + * this is supplied by the caller in the *params* argument. The + * *plen* argument indicates the len of *params* and should be set + * to 0 if *params* is NULL. + * + * The *flags* argument is reserved and must be 0. The helper is + * currently only supported for tc BPF program types, and enabled + * for IPv4 and IPv6 protocols. + * + * Returns + * The helper returns **TC_ACT_REDIRECT** on success or + * **TC_ACT_SHOT** on error. + */ +static long (*bpf_redirect_neigh)(__u32 ifindex, struct bpf_redir_neigh *params, int plen, __u64 flags) = (void *) 152; + +/* + * bpf_per_cpu_ptr + * + * Take a pointer to a percpu ksym, *percpu_ptr*, and return a + * pointer to the percpu kernel variable on *cpu*. A ksym is an + * extern variable decorated with '__ksym'. For ksym, there is a + * global var (either static or global) defined of the same name + * in the kernel. The ksym is percpu if the global var is percpu. + * The returned pointer points to the global percpu var on *cpu*. + * + * bpf_per_cpu_ptr() has the same semantic as per_cpu_ptr() in the + * kernel, except that bpf_per_cpu_ptr() may return NULL. This + * happens if *cpu* is larger than nr_cpu_ids. The caller of + * bpf_per_cpu_ptr() must check the returned value. + * + * Returns + * A pointer pointing to the kernel percpu variable on *cpu*, or + * NULL, if *cpu* is invalid. + */ +static void *(*bpf_per_cpu_ptr)(const void *percpu_ptr, __u32 cpu) = (void *) 153; + +/* + * bpf_this_cpu_ptr + * + * Take a pointer to a percpu ksym, *percpu_ptr*, and return a + * pointer to the percpu kernel variable on this cpu. See the + * description of 'ksym' in **bpf_per_cpu_ptr**\ (). + * + * bpf_this_cpu_ptr() has the same semantic as this_cpu_ptr() in + * the kernel. Different from **bpf_per_cpu_ptr**\ (), it would + * never return NULL. + * + * Returns + * A pointer pointing to the kernel percpu variable on this cpu. + */ +static void *(*bpf_this_cpu_ptr)(const void *percpu_ptr) = (void *) 154; + +/* + * bpf_redirect_peer + * + * Redirect the packet to another net device of index *ifindex*. + * This helper is somewhat similar to **bpf_redirect**\ (), except + * that the redirection happens to the *ifindex*' peer device and + * the netns switch takes place from ingress to ingress without + * going through the CPU's backlog queue. + * + * The *flags* argument is reserved and must be 0. The helper is + * currently only supported for tc BPF program types at the ingress + * hook and for veth device types. The peer device must reside in a + * different network namespace. + * + * Returns + * The helper returns **TC_ACT_REDIRECT** on success or + * **TC_ACT_SHOT** on error. + */ +static long (*bpf_redirect_peer)(__u32 ifindex, __u64 flags) = (void *) 155; + +/* + * bpf_task_storage_get + * + * Get a bpf_local_storage from the *task*. + * + * Logically, it could be thought of as getting the value from + * a *map* with *task* as the **key**. From this + * perspective, the usage is not much different from + * **bpf_map_lookup_elem**\ (*map*, **&**\ *task*) except this + * helper enforces the key must be an task_struct and the map must also + * be a **BPF_MAP_TYPE_TASK_STORAGE**. + * + * Underneath, the value is stored locally at *task* instead of + * the *map*. The *map* is used as the bpf-local-storage + * "type". The bpf-local-storage "type" (i.e. the *map*) is + * searched against all bpf_local_storage residing at *task*. + * + * An optional *flags* (**BPF_LOCAL_STORAGE_GET_F_CREATE**) can be + * used such that a new bpf_local_storage will be + * created if one does not exist. *value* can be used + * together with **BPF_LOCAL_STORAGE_GET_F_CREATE** to specify + * the initial value of a bpf_local_storage. If *value* is + * **NULL**, the new bpf_local_storage will be zero initialized. + * + * Returns + * A bpf_local_storage pointer is returned on success. + * + * **NULL** if not found or there was an error in adding + * a new bpf_local_storage. + */ +static void *(*bpf_task_storage_get)(void *map, struct task_struct *task, void *value, __u64 flags) = (void *) 156; + +/* + * bpf_task_storage_delete + * + * Delete a bpf_local_storage from a *task*. + * + * Returns + * 0 on success. + * + * **-ENOENT** if the bpf_local_storage cannot be found. + */ +static long (*bpf_task_storage_delete)(void *map, struct task_struct *task) = (void *) 157; + +/* + * bpf_get_current_task_btf + * + * Return a BTF pointer to the "current" task. + * This pointer can also be used in helpers that accept an + * *ARG_PTR_TO_BTF_ID* of type *task_struct*. + * + * Returns + * Pointer to the current task. + */ +static struct task_struct *(*bpf_get_current_task_btf)(void) = (void *) 158; + +/* + * bpf_bprm_opts_set + * + * Set or clear certain options on *bprm*: + * + * **BPF_F_BPRM_SECUREEXEC** Set the secureexec bit + * which sets the **AT_SECURE** auxv for glibc. The bit + * is cleared if the flag is not specified. + * + * Returns + * **-EINVAL** if invalid *flags* are passed, zero otherwise. + */ +static long (*bpf_bprm_opts_set)(struct linux_binprm *bprm, __u64 flags) = (void *) 159; + +/* + * bpf_ktime_get_coarse_ns + * + * Return a coarse-grained version of the time elapsed since + * system boot, in nanoseconds. Does not include time the system + * was suspended. + * + * See: **clock_gettime**\ (**CLOCK_MONOTONIC_COARSE**) + * + * Returns + * Current *ktime*. + */ +static __u64 (*bpf_ktime_get_coarse_ns)(void) = (void *) 160; + +/* + * bpf_ima_inode_hash + * + * Returns the stored IMA hash of the *inode* (if it's avaialable). + * If the hash is larger than *size*, then only *size* + * bytes will be copied to *dst* + * + * Returns + * The **hash_algo** is returned on success, + * **-EOPNOTSUP** if IMA is disabled or **-EINVAL** if + * invalid arguments are passed. + */ +static long (*bpf_ima_inode_hash)(struct inode *inode, void *dst, __u32 size) = (void *) 161; + +/* + * bpf_sock_from_file + * + * If the given file represents a socket, returns the associated + * socket. + * + * Returns + * A pointer to a struct socket on success or NULL if the file is + * not a socket. + */ +static struct socket *(*bpf_sock_from_file)(struct file *file) = (void *) 162; + +/* + * bpf_check_mtu + * + * Check packet size against exceeding MTU of net device (based + * on *ifindex*). This helper will likely be used in combination + * with helpers that adjust/change the packet size. + * + * The argument *len_diff* can be used for querying with a planned + * size change. This allows to check MTU prior to changing packet + * ctx. Providing an *len_diff* adjustment that is larger than the + * actual packet size (resulting in negative packet size) will in + * principle not exceed the MTU, why it is not considered a + * failure. Other BPF-helpers are needed for performing the + * planned size change, why the responsability for catch a negative + * packet size belong in those helpers. + * + * Specifying *ifindex* zero means the MTU check is performed + * against the current net device. This is practical if this isn't + * used prior to redirect. + * + * On input *mtu_len* must be a valid pointer, else verifier will + * reject BPF program. If the value *mtu_len* is initialized to + * zero then the ctx packet size is use. When value *mtu_len* is + * provided as input this specify the L3 length that the MTU check + * is done against. Remember XDP and TC length operate at L2, but + * this value is L3 as this correlate to MTU and IP-header tot_len + * values which are L3 (similar behavior as bpf_fib_lookup). + * + * The Linux kernel route table can configure MTUs on a more + * specific per route level, which is not provided by this helper. + * For route level MTU checks use the **bpf_fib_lookup**\ () + * helper. + * + * *ctx* is either **struct xdp_md** for XDP programs or + * **struct sk_buff** for tc cls_act programs. + * + * The *flags* argument can be a combination of one or more of the + * following values: + * + * **BPF_MTU_CHK_SEGS** + * This flag will only works for *ctx* **struct sk_buff**. + * If packet context contains extra packet segment buffers + * (often knows as GSO skb), then MTU check is harder to + * check at this point, because in transmit path it is + * possible for the skb packet to get re-segmented + * (depending on net device features). This could still be + * a MTU violation, so this flag enables performing MTU + * check against segments, with a different violation + * return code to tell it apart. Check cannot use len_diff. + * + * On return *mtu_len* pointer contains the MTU value of the net + * device. Remember the net device configured MTU is the L3 size, + * which is returned here and XDP and TC length operate at L2. + * Helper take this into account for you, but remember when using + * MTU value in your BPF-code. + * + * + * Returns + * * 0 on success, and populate MTU value in *mtu_len* pointer. + * + * * < 0 if any input argument is invalid (*mtu_len* not updated) + * + * MTU violations return positive values, but also populate MTU + * value in *mtu_len* pointer, as this can be needed for + * implementing PMTU handing: + * + * * **BPF_MTU_CHK_RET_FRAG_NEEDED** + * * **BPF_MTU_CHK_RET_SEGS_TOOBIG** + */ +static long (*bpf_check_mtu)(void *ctx, __u32 ifindex, __u32 *mtu_len, __s32 len_diff, __u64 flags) = (void *) 163; + +/* + * bpf_for_each_map_elem + * + * For each element in **map**, call **callback_fn** function with + * **map**, **callback_ctx** and other map-specific parameters. + * The **callback_fn** should be a static function and + * the **callback_ctx** should be a pointer to the stack. + * The **flags** is used to control certain aspects of the helper. + * Currently, the **flags** must be 0. + * + * The following are a list of supported map types and their + * respective expected callback signatures: + * + * BPF_MAP_TYPE_HASH, BPF_MAP_TYPE_PERCPU_HASH, + * BPF_MAP_TYPE_LRU_HASH, BPF_MAP_TYPE_LRU_PERCPU_HASH, + * BPF_MAP_TYPE_ARRAY, BPF_MAP_TYPE_PERCPU_ARRAY + * + * long (\*callback_fn)(struct bpf_map \*map, const void \*key, void \*value, void \*ctx); + * + * For per_cpu maps, the map_value is the value on the cpu where the + * bpf_prog is running. + * + * If **callback_fn** return 0, the helper will continue to the next + * element. If return value is 1, the helper will skip the rest of + * elements and return. Other return values are not used now. + * + * + * Returns + * The number of traversed map elements for success, **-EINVAL** for + * invalid **flags**. + */ +static long (*bpf_for_each_map_elem)(void *map, void *callback_fn, void *callback_ctx, __u64 flags) = (void *) 164; + +/* + * bpf_snprintf + * + * Outputs a string into the **str** buffer of size **str_size** + * based on a format string stored in a read-only map pointed by + * **fmt**. + * + * Each format specifier in **fmt** corresponds to one u64 element + * in the **data** array. For strings and pointers where pointees + * are accessed, only the pointer values are stored in the *data* + * array. The *data_len* is the size of *data* in bytes - must be + * a multiple of 8. + * + * Formats **%s** and **%p{i,I}{4,6}** require to read kernel + * memory. Reading kernel memory may fail due to either invalid + * address or valid address but requiring a major memory fault. If + * reading kernel memory fails, the string for **%s** will be an + * empty string, and the ip address for **%p{i,I}{4,6}** will be 0. + * Not returning error to bpf program is consistent with what + * **bpf_trace_printk**\ () does for now. + * + * + * Returns + * The strictly positive length of the formatted string, including + * the trailing zero character. If the return value is greater than + * **str_size**, **str** contains a truncated string, guaranteed to + * be zero-terminated except when **str_size** is 0. + * + * Or **-EBUSY** if the per-CPU memory copy buffer is busy. + */ +static long (*bpf_snprintf)(char *str, __u32 str_size, const char *fmt, __u64 *data, __u32 data_len) = (void *) 165; + +/* + * bpf_sys_bpf + * + * Execute bpf syscall with given arguments. + * + * Returns + * A syscall result. + */ +static long (*bpf_sys_bpf)(__u32 cmd, void *attr, __u32 attr_size) = (void *) 166; + +/* + * bpf_btf_find_by_name_kind + * + * Find BTF type with given name and kind in vmlinux BTF or in module's BTFs. + * + * Returns + * Returns btf_id and btf_obj_fd in lower and upper 32 bits. + */ +static long (*bpf_btf_find_by_name_kind)(char *name, int name_sz, __u32 kind, int flags) = (void *) 167; + +/* + * bpf_sys_close + * + * Execute close syscall for given FD. + * + * Returns + * A syscall result. + */ +static long (*bpf_sys_close)(__u32 fd) = (void *) 168; + +/* + * bpf_timer_init + * + * Initialize the timer. + * First 4 bits of *flags* specify clockid. + * Only CLOCK_MONOTONIC, CLOCK_REALTIME, CLOCK_BOOTTIME are allowed. + * All other bits of *flags* are reserved. + * The verifier will reject the program if *timer* is not from + * the same *map*. + * + * Returns + * 0 on success. + * **-EBUSY** if *timer* is already initialized. + * **-EINVAL** if invalid *flags* are passed. + * **-EPERM** if *timer* is in a map that doesn't have any user references. + * The user space should either hold a file descriptor to a map with timers + * or pin such map in bpffs. When map is unpinned or file descriptor is + * closed all timers in the map will be cancelled and freed. + */ +static long (*bpf_timer_init)(struct bpf_timer *timer, void *map, __u64 flags) = (void *) 169; + +/* + * bpf_timer_set_callback + * + * Configure the timer to call *callback_fn* static function. + * + * Returns + * 0 on success. + * **-EINVAL** if *timer* was not initialized with bpf_timer_init() earlier. + * **-EPERM** if *timer* is in a map that doesn't have any user references. + * The user space should either hold a file descriptor to a map with timers + * or pin such map in bpffs. When map is unpinned or file descriptor is + * closed all timers in the map will be cancelled and freed. + */ +static long (*bpf_timer_set_callback)(struct bpf_timer *timer, void *callback_fn) = (void *) 170; + +/* + * bpf_timer_start + * + * Set timer expiration N nanoseconds from the current time. The + * configured callback will be invoked in soft irq context on some cpu + * and will not repeat unless another bpf_timer_start() is made. + * In such case the next invocation can migrate to a different cpu. + * Since struct bpf_timer is a field inside map element the map + * owns the timer. The bpf_timer_set_callback() will increment refcnt + * of BPF program to make sure that callback_fn code stays valid. + * When user space reference to a map reaches zero all timers + * in a map are cancelled and corresponding program's refcnts are + * decremented. This is done to make sure that Ctrl-C of a user + * process doesn't leave any timers running. If map is pinned in + * bpffs the callback_fn can re-arm itself indefinitely. + * bpf_map_update/delete_elem() helpers and user space sys_bpf commands + * cancel and free the timer in the given map element. + * The map can contain timers that invoke callback_fn-s from different + * programs. The same callback_fn can serve different timers from + * different maps if key/value layout matches across maps. + * Every bpf_timer_set_callback() can have different callback_fn. + * + * + * Returns + * 0 on success. + * **-EINVAL** if *timer* was not initialized with bpf_timer_init() earlier + * or invalid *flags* are passed. + */ +static long (*bpf_timer_start)(struct bpf_timer *timer, __u64 nsecs, __u64 flags) = (void *) 171; + +/* + * bpf_timer_cancel + * + * Cancel the timer and wait for callback_fn to finish if it was running. + * + * Returns + * 0 if the timer was not active. + * 1 if the timer was active. + * **-EINVAL** if *timer* was not initialized with bpf_timer_init() earlier. + * **-EDEADLK** if callback_fn tried to call bpf_timer_cancel() on its + * own timer which would have led to a deadlock otherwise. + */ +static long (*bpf_timer_cancel)(struct bpf_timer *timer) = (void *) 172; + +/* + * bpf_get_func_ip + * + * Get address of the traced function (for tracing and kprobe programs). + * + * Returns + * Address of the traced function. + */ +static __u64 (*bpf_get_func_ip)(void *ctx) = (void *) 173; + +/* + * bpf_get_attach_cookie + * + * Get bpf_cookie value provided (optionally) during the program + * attachment. It might be different for each individual + * attachment, even if BPF program itself is the same. + * Expects BPF program context *ctx* as a first argument. + * + * Supported for the following program types: + * - kprobe/uprobe; + * - tracepoint; + * - perf_event. + * + * Returns + * Value specified by user at BPF link creation/attachment time + * or 0, if it was not specified. + */ +static __u64 (*bpf_get_attach_cookie)(void *ctx) = (void *) 174; + +/* + * bpf_task_pt_regs + * + * Get the struct pt_regs associated with **task**. + * + * Returns + * A pointer to struct pt_regs. + */ +static long (*bpf_task_pt_regs)(struct task_struct *task) = (void *) 175; + +/* + * bpf_get_branch_snapshot + * + * Get branch trace from hardware engines like Intel LBR. The + * hardware engine is stopped shortly after the helper is + * called. Therefore, the user need to filter branch entries + * based on the actual use case. To capture branch trace + * before the trigger point of the BPF program, the helper + * should be called at the beginning of the BPF program. + * + * The data is stored as struct perf_branch_entry into output + * buffer *entries*. *size* is the size of *entries* in bytes. + * *flags* is reserved for now and must be zero. + * + * + * Returns + * On success, number of bytes written to *buf*. On error, a + * negative value. + * + * **-EINVAL** if *flags* is not zero. + * + * **-ENOENT** if architecture does not support branch records. + */ +static long (*bpf_get_branch_snapshot)(void *entries, __u32 size, __u64 flags) = (void *) 176; + +/* + * bpf_trace_vprintk + * + * Behaves like **bpf_trace_printk**\ () helper, but takes an array of u64 + * to format and can handle more format args as a result. + * + * Arguments are to be used as in **bpf_seq_printf**\ () helper. + * + * Returns + * The number of bytes written to the buffer, or a negative error + * in case of failure. + */ +static long (*bpf_trace_vprintk)(const char *fmt, __u32 fmt_size, const void *data, __u32 data_len) = (void *) 177; + +/* + * bpf_skc_to_unix_sock + * + * Dynamically cast a *sk* pointer to a *unix_sock* pointer. + * + * Returns + * *sk* if casting is valid, or **NULL** otherwise. + */ +static struct unix_sock *(*bpf_skc_to_unix_sock)(void *sk) = (void *) 178; + +/* + * bpf_kallsyms_lookup_name + * + * Get the address of a kernel symbol, returned in *res*. *res* is + * set to 0 if the symbol is not found. + * + * Returns + * On success, zero. On error, a negative value. + * + * **-EINVAL** if *flags* is not zero. + * + * **-EINVAL** if string *name* is not the same size as *name_sz*. + * + * **-ENOENT** if symbol is not found. + * + * **-EPERM** if caller does not have permission to obtain kernel address. + */ +static long (*bpf_kallsyms_lookup_name)(const char *name, int name_sz, int flags, __u64 *res) = (void *) 179; + +/* + * bpf_find_vma + * + * Find vma of *task* that contains *addr*, call *callback_fn* + * function with *task*, *vma*, and *callback_ctx*. + * The *callback_fn* should be a static function and + * the *callback_ctx* should be a pointer to the stack. + * The *flags* is used to control certain aspects of the helper. + * Currently, the *flags* must be 0. + * + * The expected callback signature is + * + * long (\*callback_fn)(struct task_struct \*task, struct vm_area_struct \*vma, void \*callback_ctx); + * + * + * Returns + * 0 on success. + * **-ENOENT** if *task->mm* is NULL, or no vma contains *addr*. + * **-EBUSY** if failed to try lock mmap_lock. + * **-EINVAL** for invalid **flags**. + */ +static long (*bpf_find_vma)(struct task_struct *task, __u64 addr, void *callback_fn, void *callback_ctx, __u64 flags) = (void *) 180; + + diff --git a/component/ebpf/bpf/bpf_helpers.h b/component/ebpf/bpf/bpf_helpers.h new file mode 100644 index 000000000..963b1060d --- /dev/null +++ b/component/ebpf/bpf/bpf_helpers.h @@ -0,0 +1,262 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ +#ifndef __BPF_HELPERS__ +#define __BPF_HELPERS__ + +/* + * Note that bpf programs need to include either + * vmlinux.h (auto-generated from BTF) or linux/types.h + * in advance since bpf_helper_defs.h uses such types + * as __u64. + */ +#include "bpf_helper_defs.h" + +#define __uint(name, val) int (*name)[val] +#define __type(name, val) typeof(val) *name +#define __array(name, val) typeof(val) *name[] + +/* + * Helper macro to place programs, maps, license in + * different sections in elf_bpf file. Section names + * are interpreted by libbpf depending on the context (BPF programs, BPF maps, + * extern variables, etc). + * To allow use of SEC() with externs (e.g., for extern .maps declarations), + * make sure __attribute__((unused)) doesn't trigger compilation warning. + */ +#define SEC(name) \ + _Pragma("GCC diagnostic push") \ + _Pragma("GCC diagnostic ignored \"-Wignored-attributes\"") \ + __attribute__((section(name), used)) \ + _Pragma("GCC diagnostic pop") \ + +/* Avoid 'linux/stddef.h' definition of '__always_inline'. */ +#undef __always_inline +#define __always_inline inline __attribute__((always_inline)) + +#ifndef __noinline +#define __noinline __attribute__((noinline)) +#endif +#ifndef __weak +#define __weak __attribute__((weak)) +#endif + +/* + * Use __hidden attribute to mark a non-static BPF subprogram effectively + * static for BPF verifier's verification algorithm purposes, allowing more + * extensive and permissive BPF verification process, taking into account + * subprogram's caller context. + */ +#define __hidden __attribute__((visibility("hidden"))) + +/* When utilizing vmlinux.h with BPF CO-RE, user BPF programs can't include + * any system-level headers (such as stddef.h, linux/version.h, etc), and + * commonly-used macros like NULL and KERNEL_VERSION aren't available through + * vmlinux.h. This just adds unnecessary hurdles and forces users to re-define + * them on their own. So as a convenience, provide such definitions here. + */ +#ifndef NULL +#define NULL ((void *)0) +#endif + +#ifndef KERNEL_VERSION +#define KERNEL_VERSION(a, b, c) (((a) << 16) + ((b) << 8) + ((c) > 255 ? 255 : (c))) +#endif + +/* + * Helper macros to manipulate data structures + */ +#ifndef offsetof +#define offsetof(TYPE, MEMBER) ((unsigned long)&((TYPE *)0)->MEMBER) +#endif +#ifndef container_of +#define container_of(ptr, type, member) \ + ({ \ + void *__mptr = (void *)(ptr); \ + ((type *)(__mptr - offsetof(type, member))); \ + }) +#endif + +/* + * Helper macro to throw a compilation error if __bpf_unreachable() gets + * built into the resulting code. This works given BPF back end does not + * implement __builtin_trap(). This is useful to assert that certain paths + * of the program code are never used and hence eliminated by the compiler. + * + * For example, consider a switch statement that covers known cases used by + * the program. __bpf_unreachable() can then reside in the default case. If + * the program gets extended such that a case is not covered in the switch + * statement, then it will throw a build error due to the default case not + * being compiled out. + */ +#ifndef __bpf_unreachable +# define __bpf_unreachable() __builtin_trap() +#endif + +/* + * Helper function to perform a tail call with a constant/immediate map slot. + */ +#if __clang_major__ >= 8 && defined(__bpf__) +static __always_inline void +bpf_tail_call_static(void *ctx, const void *map, const __u32 slot) +{ + if (!__builtin_constant_p(slot)) + __bpf_unreachable(); + + /* + * Provide a hard guarantee that LLVM won't optimize setting r2 (map + * pointer) and r3 (constant map index) from _different paths_ ending + * up at the _same_ call insn as otherwise we won't be able to use the + * jmpq/nopl retpoline-free patching by the x86-64 JIT in the kernel + * given they mismatch. See also d2e4c1e6c294 ("bpf: Constant map key + * tracking for prog array pokes") for details on verifier tracking. + * + * Note on clobber list: we need to stay in-line with BPF calling + * convention, so even if we don't end up using r0, r4, r5, we need + * to mark them as clobber so that LLVM doesn't end up using them + * before / after the call. + */ + asm volatile("r1 = %[ctx]\n\t" + "r2 = %[map]\n\t" + "r3 = %[slot]\n\t" + "call 12" + :: [ctx]"r"(ctx), [map]"r"(map), [slot]"i"(slot) + : "r0", "r1", "r2", "r3", "r4", "r5"); +} +#endif + +/* + * Helper structure used by eBPF C program + * to describe BPF map attributes to libbpf loader + */ +struct bpf_map_def { + unsigned int type; + unsigned int key_size; + unsigned int value_size; + unsigned int max_entries; + unsigned int map_flags; +}; + +enum libbpf_pin_type { + LIBBPF_PIN_NONE, + /* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */ + LIBBPF_PIN_BY_NAME, +}; + +enum libbpf_tristate { + TRI_NO = 0, + TRI_YES = 1, + TRI_MODULE = 2, +}; + +#define __kconfig __attribute__((section(".kconfig"))) +#define __ksym __attribute__((section(".ksyms"))) + +#ifndef ___bpf_concat +#define ___bpf_concat(a, b) a ## b +#endif +#ifndef ___bpf_apply +#define ___bpf_apply(fn, n) ___bpf_concat(fn, n) +#endif +#ifndef ___bpf_nth +#define ___bpf_nth(_, _1, _2, _3, _4, _5, _6, _7, _8, _9, _a, _b, _c, N, ...) N +#endif +#ifndef ___bpf_narg +#define ___bpf_narg(...) \ + ___bpf_nth(_, ##__VA_ARGS__, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) +#endif + +#define ___bpf_fill0(arr, p, x) do {} while (0) +#define ___bpf_fill1(arr, p, x) arr[p] = x +#define ___bpf_fill2(arr, p, x, args...) arr[p] = x; ___bpf_fill1(arr, p + 1, args) +#define ___bpf_fill3(arr, p, x, args...) arr[p] = x; ___bpf_fill2(arr, p + 1, args) +#define ___bpf_fill4(arr, p, x, args...) arr[p] = x; ___bpf_fill3(arr, p + 1, args) +#define ___bpf_fill5(arr, p, x, args...) arr[p] = x; ___bpf_fill4(arr, p + 1, args) +#define ___bpf_fill6(arr, p, x, args...) arr[p] = x; ___bpf_fill5(arr, p + 1, args) +#define ___bpf_fill7(arr, p, x, args...) arr[p] = x; ___bpf_fill6(arr, p + 1, args) +#define ___bpf_fill8(arr, p, x, args...) arr[p] = x; ___bpf_fill7(arr, p + 1, args) +#define ___bpf_fill9(arr, p, x, args...) arr[p] = x; ___bpf_fill8(arr, p + 1, args) +#define ___bpf_fill10(arr, p, x, args...) arr[p] = x; ___bpf_fill9(arr, p + 1, args) +#define ___bpf_fill11(arr, p, x, args...) arr[p] = x; ___bpf_fill10(arr, p + 1, args) +#define ___bpf_fill12(arr, p, x, args...) arr[p] = x; ___bpf_fill11(arr, p + 1, args) +#define ___bpf_fill(arr, args...) \ + ___bpf_apply(___bpf_fill, ___bpf_narg(args))(arr, 0, args) + +/* + * BPF_SEQ_PRINTF to wrap bpf_seq_printf to-be-printed values + * in a structure. + */ +#define BPF_SEQ_PRINTF(seq, fmt, args...) \ +({ \ + static const char ___fmt[] = fmt; \ + unsigned long long ___param[___bpf_narg(args)]; \ + \ + _Pragma("GCC diagnostic push") \ + _Pragma("GCC diagnostic ignored \"-Wint-conversion\"") \ + ___bpf_fill(___param, args); \ + _Pragma("GCC diagnostic pop") \ + \ + bpf_seq_printf(seq, ___fmt, sizeof(___fmt), \ + ___param, sizeof(___param)); \ +}) + +/* + * BPF_SNPRINTF wraps the bpf_snprintf helper with variadic arguments instead of + * an array of u64. + */ +#define BPF_SNPRINTF(out, out_size, fmt, args...) \ +({ \ + static const char ___fmt[] = fmt; \ + unsigned long long ___param[___bpf_narg(args)]; \ + \ + _Pragma("GCC diagnostic push") \ + _Pragma("GCC diagnostic ignored \"-Wint-conversion\"") \ + ___bpf_fill(___param, args); \ + _Pragma("GCC diagnostic pop") \ + \ + bpf_snprintf(out, out_size, ___fmt, \ + ___param, sizeof(___param)); \ +}) + +#ifdef BPF_NO_GLOBAL_DATA +#define BPF_PRINTK_FMT_MOD +#else +#define BPF_PRINTK_FMT_MOD static const +#endif + +#define __bpf_printk(fmt, ...) \ +({ \ + BPF_PRINTK_FMT_MOD char ____fmt[] = fmt; \ + bpf_trace_printk(____fmt, sizeof(____fmt), \ + ##__VA_ARGS__); \ +}) + +/* + * __bpf_vprintk wraps the bpf_trace_vprintk helper with variadic arguments + * instead of an array of u64. + */ +#define __bpf_vprintk(fmt, args...) \ +({ \ + static const char ___fmt[] = fmt; \ + unsigned long long ___param[___bpf_narg(args)]; \ + \ + _Pragma("GCC diagnostic push") \ + _Pragma("GCC diagnostic ignored \"-Wint-conversion\"") \ + ___bpf_fill(___param, args); \ + _Pragma("GCC diagnostic pop") \ + \ + bpf_trace_vprintk(___fmt, sizeof(___fmt), \ + ___param, sizeof(___param)); \ +}) + +/* Use __bpf_printk when bpf_printk call has 3 or fewer fmt args + * Otherwise use __bpf_vprintk + */ +#define ___bpf_pick_printk(...) \ + ___bpf_nth(_, ##__VA_ARGS__, __bpf_vprintk, __bpf_vprintk, __bpf_vprintk, \ + __bpf_vprintk, __bpf_vprintk, __bpf_vprintk, __bpf_vprintk, \ + __bpf_vprintk, __bpf_vprintk, __bpf_printk /*3*/, __bpf_printk /*2*/,\ + __bpf_printk /*1*/, __bpf_printk /*0*/) + +/* Helper macro to print out debug messages */ +#define bpf_printk(fmt, args...) ___bpf_pick_printk(args)(fmt, ##args) + +#endif diff --git a/component/ebpf/bpf/redir.c b/component/ebpf/bpf/redir.c new file mode 100644 index 000000000..a24afec8a --- /dev/null +++ b/component/ebpf/bpf/redir.c @@ -0,0 +1,342 @@ +#include +#include +//#include + +#include +#include +//#include +//#include +#include +#include +#include +//#include + +#include + +#include "bpf_endian.h" +#include "bpf_helpers.h" + +#define IP_CSUM_OFF (ETH_HLEN + offsetof(struct iphdr, check)) +#define IP_DST_OFF (ETH_HLEN + offsetof(struct iphdr, daddr)) +#define IP_SRC_OFF (ETH_HLEN + offsetof(struct iphdr, saddr)) +#define IP_PROTO_OFF (ETH_HLEN + offsetof(struct iphdr, protocol)) +#define TCP_CSUM_OFF (ETH_HLEN + sizeof(struct iphdr) + offsetof(struct tcphdr, check)) +#define TCP_SRC_OFF (ETH_HLEN + sizeof(struct iphdr) + offsetof(struct tcphdr, source)) +#define TCP_DST_OFF (ETH_HLEN + sizeof(struct iphdr) + offsetof(struct tcphdr, dest)) +//#define UDP_CSUM_OFF (ETH_HLEN + sizeof(struct iphdr) + offsetof(struct udphdr, check)) +//#define UDP_SRC_OFF (ETH_HLEN + sizeof(struct iphdr) + offsetof(struct udphdr, source)) +//#define UDP_DST_OFF (ETH_HLEN + sizeof(struct iphdr) + offsetof(struct udphdr, dest)) +#define IS_PSEUDO 0x10 + +struct origin_info { + __be32 ip; + __be16 port; + __u16 pad; +}; + +struct origin_info *origin_info_unused __attribute__((unused)); + +struct redir_info { + __be32 sip; + __be32 dip; + __be16 sport; + __be16 dport; +}; + +struct redir_info *redir_info_unused __attribute__((unused)); + +struct { + __uint(type, BPF_MAP_TYPE_LRU_HASH); + __type(key, struct redir_info); + __type(value, struct origin_info); + __uint(max_entries, 65535); + __uint(pinning, LIBBPF_PIN_BY_NAME); +} pair_original_dst_map SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, __u32); + __type(value, __u32); + __uint(max_entries, 3); + __uint(pinning, LIBBPF_PIN_BY_NAME); +} redir_params_map SEC(".maps"); + +static __always_inline int rewrite_ip(struct __sk_buff *skb, __be32 new_ip, bool is_dest) { + int ret, off = 0, flags = IS_PSEUDO; + __be32 old_ip; + + if (is_dest) + ret = bpf_skb_load_bytes(skb, IP_DST_OFF, &old_ip, 4); + else + ret = bpf_skb_load_bytes(skb, IP_SRC_OFF, &old_ip, 4); + + if (ret < 0) { + return ret; + } + + off = TCP_CSUM_OFF; +// __u8 proto; +// +// ret = bpf_skb_load_bytes(skb, IP_PROTO_OFF, &proto, 1); +// if (ret < 0) { +// return BPF_DROP; +// } +// +// switch (proto) { +// case IPPROTO_TCP: +// off = TCP_CSUM_OFF; +// break; +// +// case IPPROTO_UDP: +// off = UDP_CSUM_OFF; +// flags |= BPF_F_MARK_MANGLED_0; +// break; +// +// case IPPROTO_ICMPV6: +// off = offsetof(struct icmp6hdr, icmp6_cksum); +// break; +// } +// +// if (off) { + ret = bpf_l4_csum_replace(skb, off, old_ip, new_ip, flags | sizeof(new_ip)); + if (ret < 0) { + return ret; + } +// } + + ret = bpf_l3_csum_replace(skb, IP_CSUM_OFF, old_ip, new_ip, sizeof(new_ip)); + if (ret < 0) { + return ret; + } + + if (is_dest) + ret = bpf_skb_store_bytes(skb, IP_DST_OFF, &new_ip, sizeof(new_ip), 0); + else + ret = bpf_skb_store_bytes(skb, IP_SRC_OFF, &new_ip, sizeof(new_ip), 0); + + if (ret < 0) { + return ret; + } + + return 1; +} + +static __always_inline int rewrite_port(struct __sk_buff *skb, __be16 new_port, bool is_dest) { + int ret, off = 0; + __be16 old_port; + + if (is_dest) + ret = bpf_skb_load_bytes(skb, TCP_DST_OFF, &old_port, 2); + else + ret = bpf_skb_load_bytes(skb, TCP_SRC_OFF, &old_port, 2); + + if (ret < 0) { + return ret; + } + + off = TCP_CSUM_OFF; + + ret = bpf_l4_csum_replace(skb, off, old_port, new_port, sizeof(new_port)); + if (ret < 0) { + return ret; + } + + if (is_dest) + ret = bpf_skb_store_bytes(skb, TCP_DST_OFF, &new_port, sizeof(new_port), 0); + else + ret = bpf_skb_store_bytes(skb, TCP_SRC_OFF, &new_port, sizeof(new_port), 0); + + if (ret < 0) { + return ret; + } + + return 1; +} + +static __always_inline bool is_lan_ip(__be32 addr) { + if (addr == 0xffffffff) + return true; + + __u8 fist = (__u8)(addr & 0xff); + + if (fist == 127 || fist == 10) + return true; + + __u8 second = (__u8)((addr >> 8) & 0xff); + + if (fist == 172 && second >= 16 && second <= 31) + return true; + + if (fist == 192 && second == 168) + return true; + + return false; +} + +SEC("tc_clash_auto_redir_ingress") +int tc_redir_ingress_func(struct __sk_buff *skb) { + void *data = (void *)(long)skb->data; + void *data_end = (void *)(long)skb->data_end; + struct ethhdr *eth = data; + + if ((void *)(eth + 1) > data_end) + return TC_ACT_OK; + + if (eth->h_proto != bpf_htons(ETH_P_IP)) + return TC_ACT_OK; + + struct iphdr *iph = (struct iphdr *)(eth + 1); + if ((void *)(iph + 1) > data_end) + return TC_ACT_OK; + + __u32 key = 0, *route_index, *redir_ip, *redir_port; + + route_index = bpf_map_lookup_elem(&redir_params_map, &key); + if (!route_index) + return TC_ACT_OK; + + if (iph->protocol == IPPROTO_ICMP && *route_index != 0) + return bpf_redirect(*route_index, 0); + + if (iph->protocol != IPPROTO_TCP) + return TC_ACT_OK; + + struct tcphdr *tcph = (struct tcphdr *)(iph + 1); + if ((void *)(tcph + 1) > data_end) + return TC_ACT_SHOT; + + key = 1; + redir_ip = bpf_map_lookup_elem(&redir_params_map, &key); + if (!redir_ip) + return TC_ACT_OK; + + key = 2; + redir_port = bpf_map_lookup_elem(&redir_params_map, &key); + if (!redir_port) + return TC_ACT_OK; + + __be32 new_ip = bpf_htonl(*redir_ip); + __be16 new_port = bpf_htonl(*redir_port) >> 16; + __be32 old_ip = iph->daddr; + __be16 old_port = tcph->dest; + + if (old_ip == new_ip || is_lan_ip(old_ip) || bpf_ntohs(old_port) == 53) { + return TC_ACT_OK; + } + + struct redir_info p_key = { + .sip = iph->saddr, + .sport = tcph->source, + .dip = new_ip, + .dport = new_port, + }; + + if (tcph->syn && !tcph->ack) { + struct origin_info origin = { + .ip = old_ip, + .port = old_port, + }; + + bpf_map_update_elem(&pair_original_dst_map, &p_key, &origin, BPF_NOEXIST); + + if (rewrite_ip(skb, new_ip, true) < 0) { + return TC_ACT_SHOT; + } + + if (rewrite_port(skb, new_port, true) < 0) { + return TC_ACT_SHOT; + } + } else { + struct origin_info *origin = bpf_map_lookup_elem(&pair_original_dst_map, &p_key); + if (!origin) { + return TC_ACT_OK; + } + + if (rewrite_ip(skb, new_ip, true) < 0) { + return TC_ACT_SHOT; + } + + if (rewrite_port(skb, new_port, true) < 0) { + return TC_ACT_SHOT; + } + } + + return TC_ACT_OK; +} + +SEC("tc_clash_auto_redir_egress") +int tc_redir_egress_func(struct __sk_buff *skb) { + void *data = (void *)(long)skb->data; + void *data_end = (void *)(long)skb->data_end; + struct ethhdr *eth = data; + + if ((void *)(eth + 1) > data_end) + return TC_ACT_OK; + + if (eth->h_proto != bpf_htons(ETH_P_IP)) + return TC_ACT_OK; + + __u32 key = 0, *redir_ip, *redir_port; // *clash_mark + +// clash_mark = bpf_map_lookup_elem(&redir_params_map, &key); +// if (clash_mark && *clash_mark != 0 && *clash_mark == skb->mark) +// return TC_ACT_OK; + + struct iphdr *iph = (struct iphdr *)(eth + 1); + if ((void *)(iph + 1) > data_end) + return TC_ACT_OK; + + if (iph->protocol != IPPROTO_TCP) + return TC_ACT_OK; + + struct tcphdr *tcph = (struct tcphdr *)(iph + 1); + if ((void *)(tcph + 1) > data_end) + return TC_ACT_SHOT; + + key = 1; + redir_ip = bpf_map_lookup_elem(&redir_params_map, &key); + if (!redir_ip) + return TC_ACT_OK; + + key = 2; + redir_port = bpf_map_lookup_elem(&redir_params_map, &key); + if (!redir_port) + return TC_ACT_OK; + + __be32 new_ip = bpf_htonl(*redir_ip); + __be16 new_port = bpf_htonl(*redir_port) >> 16; + __be32 old_ip = iph->saddr; + __be16 old_port = tcph->source; + + if (old_ip != new_ip || old_port != new_port) { + return TC_ACT_OK; + } + + struct redir_info p_key = { + .sip = iph->daddr, + .sport = tcph->dest, + .dip = iph->saddr, + .dport = tcph->source, + }; + + struct origin_info *origin = bpf_map_lookup_elem(&pair_original_dst_map, &p_key); + if (!origin) { + return TC_ACT_OK; + } + + if (tcph->fin && tcph->ack) { + bpf_map_delete_elem(&pair_original_dst_map, &p_key); + } + + if (rewrite_ip(skb, origin->ip, false) < 0) { + return TC_ACT_SHOT; + } + + if (rewrite_port(skb, origin->port, false) < 0) { + return TC_ACT_SHOT; + } + + return TC_ACT_OK; +} + +char _license[] SEC("license") = "GPL"; diff --git a/component/ebpf/bpf/tc.c b/component/ebpf/bpf/tc.c new file mode 100644 index 000000000..4eebf41ca --- /dev/null +++ b/component/ebpf/bpf/tc.c @@ -0,0 +1,103 @@ +#include +#include +#include +#include +#include +//#include +//#include +#include + +#include "bpf_endian.h" +#include "bpf_helpers.h" + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, __u32); + __type(value, __u32); + __uint(max_entries, 2); + __uint(pinning, LIBBPF_PIN_BY_NAME); +} tc_params_map SEC(".maps"); + +static __always_inline bool is_lan_ip(__be32 addr) { + if (addr == 0xffffffff) + return true; + + __u8 fist = (__u8)(addr & 0xff); + + if (fist == 127 || fist == 10) + return true; + + __u8 second = (__u8)((addr >> 8) & 0xff); + + if (fist == 172 && second >= 16 && second <= 31) + return true; + + if (fist == 192 && second == 168) + return true; + + return false; +} + +SEC("tc_clash_redirect_to_tun") +int tc_tun_func(struct __sk_buff *skb) { + void *data = (void *)(long)skb->data; + void *data_end = (void *)(long)skb->data_end; + struct ethhdr *eth = data; + + if ((void *)(eth + 1) > data_end) + return TC_ACT_OK; + + if (eth->h_proto == bpf_htons(ETH_P_ARP)) + return TC_ACT_OK; + + __u32 key = 0, *clash_mark, *tun_ifindex; + + clash_mark = bpf_map_lookup_elem(&tc_params_map, &key); + if (!clash_mark) + return TC_ACT_OK; + + if (skb->mark == *clash_mark) + return TC_ACT_OK; + + if (eth->h_proto == bpf_htons(ETH_P_IP)) { + struct iphdr *iph = (struct iphdr *)(eth + 1); + if ((void *)(iph + 1) > data_end) + return TC_ACT_OK; + + if (iph->protocol == IPPROTO_ICMP) + return TC_ACT_OK; + + __be32 daddr = iph->daddr; + + if (is_lan_ip(daddr)) + return TC_ACT_OK; + +// if (iph->protocol == IPPROTO_TCP) { +// struct tcphdr *tcph = (struct tcphdr *)(iph + 1); +// if ((void *)(tcph + 1) > data_end) +// return TC_ACT_OK; +// +// __u16 source = bpf_ntohs(tcph->source); +// if (source == 22 || source == 80 || source == 443 || source == 8080 || source == 8443 || source == 9090 || (source >= 7890 && source <= 7895)) +// return TC_ACT_OK; +// } else if (iph->protocol == IPPROTO_UDP) { +// struct udphdr *udph = (struct udphdr *)(iph + 1); +// if ((void *)(udph + 1) > data_end) +// return TC_ACT_OK; +// +// __u16 source = bpf_ntohs(udph->source); +// if (source == 53 || (source >= 135 && source <= 139)) +// return TC_ACT_OK; +// } + } + + key = 1; + tun_ifindex = bpf_map_lookup_elem(&tc_params_map, &key); + if (!tun_ifindex) + return TC_ACT_OK; + + //return bpf_redirect(*tun_ifindex, BPF_F_INGRESS); // __bpf_rx_skb + return bpf_redirect(*tun_ifindex, 0); // __bpf_tx_skb / __dev_xmit_skb +} + +char _license[] SEC("license") = "GPL"; diff --git a/component/ebpf/byteorder/byteorder.go b/component/ebpf/byteorder/byteorder.go new file mode 100644 index 000000000..63e0c611a --- /dev/null +++ b/component/ebpf/byteorder/byteorder.go @@ -0,0 +1,13 @@ +package byteorder + +import ( + "net" +) + +// NetIPv4ToHost32 converts an net.IP to a uint32 in host byte order. ip +// must be a IPv4 address, otherwise the function will panic. +func NetIPv4ToHost32(ip net.IP) uint32 { + ipv4 := ip.To4() + _ = ipv4[3] // Assert length of ipv4. + return Native.Uint32(ipv4) +} diff --git a/component/ebpf/byteorder/byteorder_bigendian.go b/component/ebpf/byteorder/byteorder_bigendian.go new file mode 100644 index 000000000..4c5d71058 --- /dev/null +++ b/component/ebpf/byteorder/byteorder_bigendian.go @@ -0,0 +1,12 @@ +//go:build arm64be || armbe || mips || mips64 || mips64p32 || ppc64 || s390 || s390x || sparc || sparc64 + +package byteorder + +import "encoding/binary" + +var Native binary.ByteOrder = binary.BigEndian + +func HostToNetwork16(u uint16) uint16 { return u } +func HostToNetwork32(u uint32) uint32 { return u } +func NetworkToHost16(u uint16) uint16 { return u } +func NetworkToHost32(u uint32) uint32 { return u } diff --git a/component/ebpf/byteorder/byteorder_littleendian.go b/component/ebpf/byteorder/byteorder_littleendian.go new file mode 100644 index 000000000..216a5e5ab --- /dev/null +++ b/component/ebpf/byteorder/byteorder_littleendian.go @@ -0,0 +1,15 @@ +//go:build 386 || amd64 || amd64p32 || arm || arm64 || mips64le || mips64p32le || mipsle || ppc64le || riscv64 + +package byteorder + +import ( + "encoding/binary" + "math/bits" +) + +var Native binary.ByteOrder = binary.LittleEndian + +func HostToNetwork16(u uint16) uint16 { return bits.ReverseBytes16(u) } +func HostToNetwork32(u uint32) uint32 { return bits.ReverseBytes32(u) } +func NetworkToHost16(u uint16) uint16 { return bits.ReverseBytes16(u) } +func NetworkToHost32(u uint32) uint32 { return bits.ReverseBytes32(u) } diff --git a/component/ebpf/ebpf.go b/component/ebpf/ebpf.go new file mode 100644 index 000000000..6257675cb --- /dev/null +++ b/component/ebpf/ebpf.go @@ -0,0 +1,33 @@ +package ebpf + +import ( + "net/netip" + + C "github.com/Dreamacro/clash/constant" + "github.com/Dreamacro/clash/transport/socks5" +) + +type TcEBpfProgram struct { + pros []C.EBpf + rawNICs []string +} + +func (t *TcEBpfProgram) RawNICs() []string { + return t.rawNICs +} + +func (t *TcEBpfProgram) Close() { + for _, p := range t.pros { + p.Close() + } +} + +func (t *TcEBpfProgram) Lookup(srcAddrPort netip.AddrPort) (addr socks5.Addr, err error) { + for _, p := range t.pros { + addr, err = p.Lookup(srcAddrPort) + if err == nil { + return + } + } + return +} diff --git a/component/ebpf/ebpf_linux.go b/component/ebpf/ebpf_linux.go new file mode 100644 index 000000000..6893ae48e --- /dev/null +++ b/component/ebpf/ebpf_linux.go @@ -0,0 +1,112 @@ +package ebpf + +import ( + "fmt" + "net/netip" + + "github.com/vishvananda/netlink" + + "github.com/Dreamacro/clash/common/cmd" + "github.com/Dreamacro/clash/component/dialer" + "github.com/Dreamacro/clash/component/ebpf/redir" + "github.com/Dreamacro/clash/component/ebpf/tc" + C "github.com/Dreamacro/clash/constant" +) + +// NewTcEBpfProgram new redirect to tun ebpf program +func NewTcEBpfProgram(ifaceNames []string, tunName string) (*TcEBpfProgram, error) { + tunIface, err := netlink.LinkByName(tunName) + if err != nil { + return nil, fmt.Errorf("lookup network iface %q: %w", tunName, err) + } + + tunIndex := uint32(tunIface.Attrs().Index) + + dialer.DefaultRoutingMark.Store(C.ClashTrafficMark) + + ifMark := uint32(dialer.DefaultRoutingMark.Load()) + + var pros []C.EBpf + for _, ifaceName := range ifaceNames { + iface, err := netlink.LinkByName(ifaceName) + if err != nil { + return nil, fmt.Errorf("lookup network iface %q: %w", ifaceName, err) + } + if iface.Attrs().OperState != netlink.OperUp { + return nil, fmt.Errorf("network iface %q is down", ifaceName) + } + + attrs := iface.Attrs() + index := attrs.Index + + tcPro := tc.NewEBpfTc(ifaceName, index, ifMark, tunIndex) + if err = tcPro.Start(); err != nil { + return nil, err + } + + pros = append(pros, tcPro) + } + + systemSetting(ifaceNames...) + + return &TcEBpfProgram{pros: pros, rawNICs: ifaceNames}, nil +} + +// NewRedirEBpfProgram new auto redirect ebpf program +func NewRedirEBpfProgram(ifaceNames []string, redirPort uint16, defaultRouteInterfaceName string) (*TcEBpfProgram, error) { + defaultRouteInterface, err := netlink.LinkByName(defaultRouteInterfaceName) + if err != nil { + return nil, fmt.Errorf("lookup network iface %q: %w", defaultRouteInterfaceName, err) + } + + defaultRouteIndex := uint32(defaultRouteInterface.Attrs().Index) + + var pros []C.EBpf + for _, ifaceName := range ifaceNames { + iface, err := netlink.LinkByName(ifaceName) + if err != nil { + return nil, fmt.Errorf("lookup network iface %q: %w", ifaceName, err) + } + + attrs := iface.Attrs() + index := attrs.Index + + addrs, err := netlink.AddrList(iface, netlink.FAMILY_V4) + if err != nil { + return nil, fmt.Errorf("lookup network iface %q address: %w", ifaceName, err) + } + + if len(addrs) == 0 { + return nil, fmt.Errorf("network iface %q does not contain any ipv4 addresses", ifaceName) + } + + address, _ := netip.AddrFromSlice(addrs[0].IP) + redirAddrPort := netip.AddrPortFrom(address, redirPort) + + redirPro := redir.NewEBpfRedirect(ifaceName, index, 0, defaultRouteIndex, redirAddrPort) + if err = redirPro.Start(); err != nil { + return nil, err + } + + pros = append(pros, redirPro) + } + + systemSetting(ifaceNames...) + + return &TcEBpfProgram{pros: pros, rawNICs: ifaceNames}, nil +} + +func systemSetting(ifaceNames ...string) { + _, _ = cmd.ExecCmd("sysctl -w net.ipv4.ip_forward=1") + _, _ = cmd.ExecCmd("sysctl -w net.ipv4.conf.all.forwarding=1") + _, _ = cmd.ExecCmd("sysctl -w net.ipv4.conf.all.accept_local=1") + _, _ = cmd.ExecCmd("sysctl -w net.ipv4.conf.all.accept_redirects=1") + _, _ = cmd.ExecCmd("sysctl -w net.ipv4.conf.all.rp_filter=0") + + for _, ifaceName := range ifaceNames { + _, _ = cmd.ExecCmd(fmt.Sprintf("sysctl -w net.ipv4.conf.%s.forwarding=1", ifaceName)) + _, _ = cmd.ExecCmd(fmt.Sprintf("sysctl -w net.ipv4.conf.%s.accept_local=1", ifaceName)) + _, _ = cmd.ExecCmd(fmt.Sprintf("sysctl -w net.ipv4.conf.%s.accept_redirects=1", ifaceName)) + _, _ = cmd.ExecCmd(fmt.Sprintf("sysctl -w net.ipv4.conf.%s.rp_filter=0", ifaceName)) + } +} diff --git a/component/ebpf/ebpf_others.go b/component/ebpf/ebpf_others.go new file mode 100644 index 000000000..53658ffef --- /dev/null +++ b/component/ebpf/ebpf_others.go @@ -0,0 +1,17 @@ +//go:build !linux + +package ebpf + +import ( + "fmt" +) + +// NewTcEBpfProgram new ebpf tc program +func NewTcEBpfProgram(_ []string, _ string) (*TcEBpfProgram, error) { + return nil, fmt.Errorf("system not supported") +} + +// NewRedirEBpfProgram new ebpf redirect program +func NewRedirEBpfProgram(_ []string, _ uint16, _ string) (*TcEBpfProgram, error) { + return nil, fmt.Errorf("system not supported") +} diff --git a/component/ebpf/redir/auto_redirect.go b/component/ebpf/redir/auto_redirect.go new file mode 100644 index 000000000..2d1b48780 --- /dev/null +++ b/component/ebpf/redir/auto_redirect.go @@ -0,0 +1,216 @@ +//go:build linux + +package redir + +import ( + "encoding/binary" + "fmt" + "io" + "net" + "net/netip" + "os" + "path/filepath" + + "github.com/cilium/ebpf" + "github.com/cilium/ebpf/rlimit" + "github.com/vishvananda/netlink" + "golang.org/x/sys/unix" + + "github.com/Dreamacro/clash/component/ebpf/byteorder" + C "github.com/Dreamacro/clash/constant" + "github.com/Dreamacro/clash/transport/socks5" +) + +//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS bpf ../bpf/redir.c + +const ( + mapKey1 uint32 = 0 + mapKey2 uint32 = 1 + mapKey3 uint32 = 2 +) + +type EBpfRedirect struct { + objs io.Closer + originMap *ebpf.Map + qdisc netlink.Qdisc + filter netlink.Filter + filterEgress netlink.Filter + + ifName string + ifIndex int + ifMark uint32 + rtIndex uint32 + redirIp uint32 + redirPort uint16 + + bpfPath string +} + +func NewEBpfRedirect(ifName string, ifIndex int, ifMark uint32, routeIndex uint32, redirAddrPort netip.AddrPort) *EBpfRedirect { + return &EBpfRedirect{ + ifName: ifName, + ifIndex: ifIndex, + ifMark: ifMark, + rtIndex: routeIndex, + redirIp: binary.BigEndian.Uint32(redirAddrPort.Addr().AsSlice()), + redirPort: redirAddrPort.Port(), + } +} + +func (e *EBpfRedirect) Start() error { + if err := rlimit.RemoveMemlock(); err != nil { + return fmt.Errorf("remove memory lock: %w", err) + } + + e.bpfPath = filepath.Join(C.BpfFSPath, e.ifName) + if err := os.MkdirAll(e.bpfPath, os.ModePerm); err != nil { + return fmt.Errorf("failed to create bpf fs subpath: %w", err) + } + + var objs bpfObjects + if err := loadBpfObjects(&objs, &ebpf.CollectionOptions{ + Maps: ebpf.MapOptions{ + PinPath: e.bpfPath, + }, + }); err != nil { + e.Close() + return fmt.Errorf("loading objects: %w", err) + } + + e.objs = &objs + e.originMap = objs.bpfMaps.PairOriginalDstMap + + if err := objs.bpfMaps.RedirParamsMap.Update(mapKey1, e.rtIndex, ebpf.UpdateAny); err != nil { + e.Close() + return fmt.Errorf("storing objects: %w", err) + } + + if err := objs.bpfMaps.RedirParamsMap.Update(mapKey2, e.redirIp, ebpf.UpdateAny); err != nil { + e.Close() + return fmt.Errorf("storing objects: %w", err) + } + + if err := objs.bpfMaps.RedirParamsMap.Update(mapKey3, uint32(e.redirPort), ebpf.UpdateAny); err != nil { + e.Close() + return fmt.Errorf("storing objects: %w", err) + } + + attrs := netlink.QdiscAttrs{ + LinkIndex: e.ifIndex, + Handle: netlink.MakeHandle(0xffff, 0), + Parent: netlink.HANDLE_CLSACT, + } + + qdisc := &netlink.GenericQdisc{ + QdiscAttrs: attrs, + QdiscType: "clsact", + } + + e.qdisc = qdisc + + if err := netlink.QdiscAdd(qdisc); err != nil { + if os.IsExist(err) { + _ = netlink.QdiscDel(qdisc) + err = netlink.QdiscAdd(qdisc) + } + + if err != nil { + e.Close() + return fmt.Errorf("cannot add clsact qdisc: %w", err) + } + } + + filterAttrs := netlink.FilterAttrs{ + LinkIndex: e.ifIndex, + Parent: netlink.HANDLE_MIN_INGRESS, + Handle: netlink.MakeHandle(0, 1), + Protocol: unix.ETH_P_IP, + Priority: 0, + } + + filter := &netlink.BpfFilter{ + FilterAttrs: filterAttrs, + Fd: objs.bpfPrograms.TcRedirIngressFunc.FD(), + Name: "clash-redir-ingress-" + e.ifName, + DirectAction: true, + } + + if err := netlink.FilterAdd(filter); err != nil { + e.Close() + return fmt.Errorf("cannot attach ebpf object to filter ingress: %w", err) + } + + e.filter = filter + + filterAttrsEgress := netlink.FilterAttrs{ + LinkIndex: e.ifIndex, + Parent: netlink.HANDLE_MIN_EGRESS, + Handle: netlink.MakeHandle(0, 1), + Protocol: unix.ETH_P_IP, + Priority: 0, + } + + filterEgress := &netlink.BpfFilter{ + FilterAttrs: filterAttrsEgress, + Fd: objs.bpfPrograms.TcRedirEgressFunc.FD(), + Name: "clash-redir-egress-" + e.ifName, + DirectAction: true, + } + + if err := netlink.FilterAdd(filterEgress); err != nil { + e.Close() + return fmt.Errorf("cannot attach ebpf object to filter egress: %w", err) + } + + e.filterEgress = filterEgress + + return nil +} + +func (e *EBpfRedirect) Close() { + if e.filter != nil { + _ = netlink.FilterDel(e.filter) + } + if e.filterEgress != nil { + _ = netlink.FilterDel(e.filterEgress) + } + if e.qdisc != nil { + _ = netlink.QdiscDel(e.qdisc) + } + if e.objs != nil { + _ = e.objs.Close() + } + _ = os.Remove(filepath.Join(e.bpfPath, "redir_params_map")) + _ = os.Remove(filepath.Join(e.bpfPath, "pair_original_dst_map")) +} + +func (e *EBpfRedirect) Lookup(srcAddrPort netip.AddrPort) (socks5.Addr, error) { + rAddr := srcAddrPort.Addr().Unmap() + if rAddr.Is6() { + return nil, fmt.Errorf("remote address is ipv6") + } + + srcIp := binary.BigEndian.Uint32(rAddr.AsSlice()) + scrPort := srcAddrPort.Port() + + key := bpfRedirInfo{ + Sip: byteorder.HostToNetwork32(srcIp), + Sport: byteorder.HostToNetwork16(scrPort), + Dip: byteorder.HostToNetwork32(e.redirIp), + Dport: byteorder.HostToNetwork16(e.redirPort), + } + + origin := bpfOriginInfo{} + + err := e.originMap.Lookup(key, &origin) + if err != nil { + return nil, err + } + + addr := make([]byte, net.IPv4len+3) + addr[0] = socks5.AtypIPv4 + + binary.BigEndian.PutUint32(addr[1:1+net.IPv4len], byteorder.NetworkToHost32(origin.Ip)) // big end + binary.BigEndian.PutUint16(addr[1+net.IPv4len:3+net.IPv4len], byteorder.NetworkToHost16(origin.Port)) // big end + return addr, nil +} diff --git a/component/ebpf/redir/bpf_bpfeb.go b/component/ebpf/redir/bpf_bpfeb.go new file mode 100644 index 000000000..ec0e1a773 --- /dev/null +++ b/component/ebpf/redir/bpf_bpfeb.go @@ -0,0 +1,138 @@ +// Code generated by bpf2go; DO NOT EDIT. +//go:build arm64be || armbe || mips || mips64 || mips64p32 || ppc64 || s390 || s390x || sparc || sparc64 +// +build arm64be armbe mips mips64 mips64p32 ppc64 s390 s390x sparc sparc64 + +package redir + +import ( + "bytes" + _ "embed" + "fmt" + "io" + + "github.com/cilium/ebpf" +) + +type bpfOriginInfo struct { + Ip uint32 + Port uint16 + Pad uint16 +} + +type bpfRedirInfo struct { + Sip uint32 + Dip uint32 + Sport uint16 + Dport uint16 +} + +// loadBpf returns the embedded CollectionSpec for bpf. +func loadBpf() (*ebpf.CollectionSpec, error) { + reader := bytes.NewReader(_BpfBytes) + spec, err := ebpf.LoadCollectionSpecFromReader(reader) + if err != nil { + return nil, fmt.Errorf("can't load bpf: %w", err) + } + + return spec, err +} + +// loadBpfObjects loads bpf and converts it into a struct. +// +// The following types are suitable as obj argument: +// +// *bpfObjects +// *bpfPrograms +// *bpfMaps +// +// See ebpf.CollectionSpec.LoadAndAssign documentation for details. +func loadBpfObjects(obj interface{}, opts *ebpf.CollectionOptions) error { + spec, err := loadBpf() + if err != nil { + return err + } + + return spec.LoadAndAssign(obj, opts) +} + +// bpfSpecs contains maps and programs before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfSpecs struct { + bpfProgramSpecs + bpfMapSpecs +} + +// bpfSpecs contains programs before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfProgramSpecs struct { + TcRedirEgressFunc *ebpf.ProgramSpec `ebpf:"tc_redir_egress_func"` + TcRedirIngressFunc *ebpf.ProgramSpec `ebpf:"tc_redir_ingress_func"` +} + +// bpfMapSpecs contains maps before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfMapSpecs struct { + PairOriginalDstMap *ebpf.MapSpec `ebpf:"pair_original_dst_map"` + RedirParamsMap *ebpf.MapSpec `ebpf:"redir_params_map"` +} + +// bpfObjects contains all objects after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfObjects struct { + bpfPrograms + bpfMaps +} + +func (o *bpfObjects) Close() error { + return _BpfClose( + &o.bpfPrograms, + &o.bpfMaps, + ) +} + +// bpfMaps contains all maps after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfMaps struct { + PairOriginalDstMap *ebpf.Map `ebpf:"pair_original_dst_map"` + RedirParamsMap *ebpf.Map `ebpf:"redir_params_map"` +} + +func (m *bpfMaps) Close() error { + return _BpfClose( + m.PairOriginalDstMap, + m.RedirParamsMap, + ) +} + +// bpfPrograms contains all programs after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfPrograms struct { + TcRedirEgressFunc *ebpf.Program `ebpf:"tc_redir_egress_func"` + TcRedirIngressFunc *ebpf.Program `ebpf:"tc_redir_ingress_func"` +} + +func (p *bpfPrograms) Close() error { + return _BpfClose( + p.TcRedirEgressFunc, + p.TcRedirIngressFunc, + ) +} + +func _BpfClose(closers ...io.Closer) error { + for _, closer := range closers { + if err := closer.Close(); err != nil { + return err + } + } + return nil +} + +// Do not access this directly. +//go:embed bpf_bpfeb.o +var _BpfBytes []byte diff --git a/component/ebpf/redir/bpf_bpfeb.o b/component/ebpf/redir/bpf_bpfeb.o new file mode 100644 index 000000000..ed5116919 Binary files /dev/null and b/component/ebpf/redir/bpf_bpfeb.o differ diff --git a/component/ebpf/redir/bpf_bpfel.go b/component/ebpf/redir/bpf_bpfel.go new file mode 100644 index 000000000..ed859e5df --- /dev/null +++ b/component/ebpf/redir/bpf_bpfel.go @@ -0,0 +1,138 @@ +// Code generated by bpf2go; DO NOT EDIT. +//go:build 386 || amd64 || amd64p32 || arm || arm64 || mips64le || mips64p32le || mipsle || ppc64le || riscv64 +// +build 386 amd64 amd64p32 arm arm64 mips64le mips64p32le mipsle ppc64le riscv64 + +package redir + +import ( + "bytes" + _ "embed" + "fmt" + "io" + + "github.com/cilium/ebpf" +) + +type bpfOriginInfo struct { + Ip uint32 + Port uint16 + Pad uint16 +} + +type bpfRedirInfo struct { + Sip uint32 + Dip uint32 + Sport uint16 + Dport uint16 +} + +// loadBpf returns the embedded CollectionSpec for bpf. +func loadBpf() (*ebpf.CollectionSpec, error) { + reader := bytes.NewReader(_BpfBytes) + spec, err := ebpf.LoadCollectionSpecFromReader(reader) + if err != nil { + return nil, fmt.Errorf("can't load bpf: %w", err) + } + + return spec, err +} + +// loadBpfObjects loads bpf and converts it into a struct. +// +// The following types are suitable as obj argument: +// +// *bpfObjects +// *bpfPrograms +// *bpfMaps +// +// See ebpf.CollectionSpec.LoadAndAssign documentation for details. +func loadBpfObjects(obj interface{}, opts *ebpf.CollectionOptions) error { + spec, err := loadBpf() + if err != nil { + return err + } + + return spec.LoadAndAssign(obj, opts) +} + +// bpfSpecs contains maps and programs before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfSpecs struct { + bpfProgramSpecs + bpfMapSpecs +} + +// bpfSpecs contains programs before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfProgramSpecs struct { + TcRedirEgressFunc *ebpf.ProgramSpec `ebpf:"tc_redir_egress_func"` + TcRedirIngressFunc *ebpf.ProgramSpec `ebpf:"tc_redir_ingress_func"` +} + +// bpfMapSpecs contains maps before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfMapSpecs struct { + PairOriginalDstMap *ebpf.MapSpec `ebpf:"pair_original_dst_map"` + RedirParamsMap *ebpf.MapSpec `ebpf:"redir_params_map"` +} + +// bpfObjects contains all objects after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfObjects struct { + bpfPrograms + bpfMaps +} + +func (o *bpfObjects) Close() error { + return _BpfClose( + &o.bpfPrograms, + &o.bpfMaps, + ) +} + +// bpfMaps contains all maps after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfMaps struct { + PairOriginalDstMap *ebpf.Map `ebpf:"pair_original_dst_map"` + RedirParamsMap *ebpf.Map `ebpf:"redir_params_map"` +} + +func (m *bpfMaps) Close() error { + return _BpfClose( + m.PairOriginalDstMap, + m.RedirParamsMap, + ) +} + +// bpfPrograms contains all programs after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfPrograms struct { + TcRedirEgressFunc *ebpf.Program `ebpf:"tc_redir_egress_func"` + TcRedirIngressFunc *ebpf.Program `ebpf:"tc_redir_ingress_func"` +} + +func (p *bpfPrograms) Close() error { + return _BpfClose( + p.TcRedirEgressFunc, + p.TcRedirIngressFunc, + ) +} + +func _BpfClose(closers ...io.Closer) error { + for _, closer := range closers { + if err := closer.Close(); err != nil { + return err + } + } + return nil +} + +// Do not access this directly. +//go:embed bpf_bpfel.o +var _BpfBytes []byte diff --git a/component/ebpf/redir/bpf_bpfel.o b/component/ebpf/redir/bpf_bpfel.o new file mode 100644 index 000000000..0ac4be06b Binary files /dev/null and b/component/ebpf/redir/bpf_bpfel.o differ diff --git a/component/ebpf/tc/bpf_bpfeb.go b/component/ebpf/tc/bpf_bpfeb.go new file mode 100644 index 000000000..128475384 --- /dev/null +++ b/component/ebpf/tc/bpf_bpfeb.go @@ -0,0 +1,119 @@ +// Code generated by bpf2go; DO NOT EDIT. +//go:build arm64be || armbe || mips || mips64 || mips64p32 || ppc64 || s390 || s390x || sparc || sparc64 +// +build arm64be armbe mips mips64 mips64p32 ppc64 s390 s390x sparc sparc64 + +package tc + +import ( + "bytes" + _ "embed" + "fmt" + "io" + + "github.com/cilium/ebpf" +) + +// loadBpf returns the embedded CollectionSpec for bpf. +func loadBpf() (*ebpf.CollectionSpec, error) { + reader := bytes.NewReader(_BpfBytes) + spec, err := ebpf.LoadCollectionSpecFromReader(reader) + if err != nil { + return nil, fmt.Errorf("can't load bpf: %w", err) + } + + return spec, err +} + +// loadBpfObjects loads bpf and converts it into a struct. +// +// The following types are suitable as obj argument: +// +// *bpfObjects +// *bpfPrograms +// *bpfMaps +// +// See ebpf.CollectionSpec.LoadAndAssign documentation for details. +func loadBpfObjects(obj interface{}, opts *ebpf.CollectionOptions) error { + spec, err := loadBpf() + if err != nil { + return err + } + + return spec.LoadAndAssign(obj, opts) +} + +// bpfSpecs contains maps and programs before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfSpecs struct { + bpfProgramSpecs + bpfMapSpecs +} + +// bpfSpecs contains programs before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfProgramSpecs struct { + TcTunFunc *ebpf.ProgramSpec `ebpf:"tc_tun_func"` +} + +// bpfMapSpecs contains maps before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfMapSpecs struct { + TcParamsMap *ebpf.MapSpec `ebpf:"tc_params_map"` +} + +// bpfObjects contains all objects after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfObjects struct { + bpfPrograms + bpfMaps +} + +func (o *bpfObjects) Close() error { + return _BpfClose( + &o.bpfPrograms, + &o.bpfMaps, + ) +} + +// bpfMaps contains all maps after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfMaps struct { + TcParamsMap *ebpf.Map `ebpf:"tc_params_map"` +} + +func (m *bpfMaps) Close() error { + return _BpfClose( + m.TcParamsMap, + ) +} + +// bpfPrograms contains all programs after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfPrograms struct { + TcTunFunc *ebpf.Program `ebpf:"tc_tun_func"` +} + +func (p *bpfPrograms) Close() error { + return _BpfClose( + p.TcTunFunc, + ) +} + +func _BpfClose(closers ...io.Closer) error { + for _, closer := range closers { + if err := closer.Close(); err != nil { + return err + } + } + return nil +} + +// Do not access this directly. +//go:embed bpf_bpfeb.o +var _BpfBytes []byte diff --git a/component/ebpf/tc/bpf_bpfeb.o b/component/ebpf/tc/bpf_bpfeb.o new file mode 100644 index 000000000..f0e7e608f Binary files /dev/null and b/component/ebpf/tc/bpf_bpfeb.o differ diff --git a/component/ebpf/tc/bpf_bpfel.go b/component/ebpf/tc/bpf_bpfel.go new file mode 100644 index 000000000..c09e35bbe --- /dev/null +++ b/component/ebpf/tc/bpf_bpfel.go @@ -0,0 +1,119 @@ +// Code generated by bpf2go; DO NOT EDIT. +//go:build 386 || amd64 || amd64p32 || arm || arm64 || mips64le || mips64p32le || mipsle || ppc64le || riscv64 +// +build 386 amd64 amd64p32 arm arm64 mips64le mips64p32le mipsle ppc64le riscv64 + +package tc + +import ( + "bytes" + _ "embed" + "fmt" + "io" + + "github.com/cilium/ebpf" +) + +// loadBpf returns the embedded CollectionSpec for bpf. +func loadBpf() (*ebpf.CollectionSpec, error) { + reader := bytes.NewReader(_BpfBytes) + spec, err := ebpf.LoadCollectionSpecFromReader(reader) + if err != nil { + return nil, fmt.Errorf("can't load bpf: %w", err) + } + + return spec, err +} + +// loadBpfObjects loads bpf and converts it into a struct. +// +// The following types are suitable as obj argument: +// +// *bpfObjects +// *bpfPrograms +// *bpfMaps +// +// See ebpf.CollectionSpec.LoadAndAssign documentation for details. +func loadBpfObjects(obj interface{}, opts *ebpf.CollectionOptions) error { + spec, err := loadBpf() + if err != nil { + return err + } + + return spec.LoadAndAssign(obj, opts) +} + +// bpfSpecs contains maps and programs before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfSpecs struct { + bpfProgramSpecs + bpfMapSpecs +} + +// bpfSpecs contains programs before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfProgramSpecs struct { + TcTunFunc *ebpf.ProgramSpec `ebpf:"tc_tun_func"` +} + +// bpfMapSpecs contains maps before they are loaded into the kernel. +// +// It can be passed ebpf.CollectionSpec.Assign. +type bpfMapSpecs struct { + TcParamsMap *ebpf.MapSpec `ebpf:"tc_params_map"` +} + +// bpfObjects contains all objects after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfObjects struct { + bpfPrograms + bpfMaps +} + +func (o *bpfObjects) Close() error { + return _BpfClose( + &o.bpfPrograms, + &o.bpfMaps, + ) +} + +// bpfMaps contains all maps after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfMaps struct { + TcParamsMap *ebpf.Map `ebpf:"tc_params_map"` +} + +func (m *bpfMaps) Close() error { + return _BpfClose( + m.TcParamsMap, + ) +} + +// bpfPrograms contains all programs after they have been loaded into the kernel. +// +// It can be passed to loadBpfObjects or ebpf.CollectionSpec.LoadAndAssign. +type bpfPrograms struct { + TcTunFunc *ebpf.Program `ebpf:"tc_tun_func"` +} + +func (p *bpfPrograms) Close() error { + return _BpfClose( + p.TcTunFunc, + ) +} + +func _BpfClose(closers ...io.Closer) error { + for _, closer := range closers { + if err := closer.Close(); err != nil { + return err + } + } + return nil +} + +// Do not access this directly. +//go:embed bpf_bpfel.o +var _BpfBytes []byte diff --git a/component/ebpf/tc/bpf_bpfel.o b/component/ebpf/tc/bpf_bpfel.o new file mode 100644 index 000000000..290ae9cad Binary files /dev/null and b/component/ebpf/tc/bpf_bpfel.o differ diff --git a/component/ebpf/tc/redirect_to_tun.go b/component/ebpf/tc/redirect_to_tun.go new file mode 100644 index 000000000..3fbaeb1bc --- /dev/null +++ b/component/ebpf/tc/redirect_to_tun.go @@ -0,0 +1,147 @@ +//go:build linux + +package tc + +import ( + "fmt" + "io" + "net/netip" + "os" + "path/filepath" + + "github.com/cilium/ebpf" + "github.com/cilium/ebpf/rlimit" + "github.com/vishvananda/netlink" + "golang.org/x/sys/unix" + + C "github.com/Dreamacro/clash/constant" + "github.com/Dreamacro/clash/transport/socks5" +) + +//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS bpf ../bpf/tc.c + +const ( + mapKey1 uint32 = 0 + mapKey2 uint32 = 1 +) + +type EBpfTC struct { + objs io.Closer + qdisc netlink.Qdisc + filter netlink.Filter + + ifName string + ifIndex int + ifMark uint32 + tunIfIndex uint32 + + bpfPath string +} + +func NewEBpfTc(ifName string, ifIndex int, ifMark uint32, tunIfIndex uint32) *EBpfTC { + return &EBpfTC{ + ifName: ifName, + ifIndex: ifIndex, + ifMark: ifMark, + tunIfIndex: tunIfIndex, + } +} + +func (e *EBpfTC) Start() error { + if err := rlimit.RemoveMemlock(); err != nil { + return fmt.Errorf("remove memory lock: %w", err) + } + + e.bpfPath = filepath.Join(C.BpfFSPath, e.ifName) + if err := os.MkdirAll(e.bpfPath, os.ModePerm); err != nil { + return fmt.Errorf("failed to create bpf fs subpath: %w", err) + } + + var objs bpfObjects + if err := loadBpfObjects(&objs, &ebpf.CollectionOptions{ + Maps: ebpf.MapOptions{ + PinPath: e.bpfPath, + }, + }); err != nil { + e.Close() + return fmt.Errorf("loading objects: %w", err) + } + + e.objs = &objs + + if err := objs.bpfMaps.TcParamsMap.Update(mapKey1, e.ifMark, ebpf.UpdateAny); err != nil { + e.Close() + return fmt.Errorf("storing objects: %w", err) + } + + if err := objs.bpfMaps.TcParamsMap.Update(mapKey2, e.tunIfIndex, ebpf.UpdateAny); err != nil { + e.Close() + return fmt.Errorf("storing objects: %w", err) + } + + attrs := netlink.QdiscAttrs{ + LinkIndex: e.ifIndex, + Handle: netlink.MakeHandle(0xffff, 0), + Parent: netlink.HANDLE_CLSACT, + } + + qdisc := &netlink.GenericQdisc{ + QdiscAttrs: attrs, + QdiscType: "clsact", + } + + e.qdisc = qdisc + + if err := netlink.QdiscAdd(qdisc); err != nil { + if os.IsExist(err) { + _ = netlink.QdiscDel(qdisc) + err = netlink.QdiscAdd(qdisc) + } + + if err != nil { + e.Close() + return fmt.Errorf("cannot add clsact qdisc: %w", err) + } + } + + filterAttrs := netlink.FilterAttrs{ + LinkIndex: e.ifIndex, + Parent: netlink.HANDLE_MIN_EGRESS, + Handle: netlink.MakeHandle(0, 1), + Protocol: unix.ETH_P_ALL, + Priority: 1, + } + + filter := &netlink.BpfFilter{ + FilterAttrs: filterAttrs, + Fd: objs.bpfPrograms.TcTunFunc.FD(), + Name: "clash-tc-" + e.ifName, + DirectAction: true, + } + + if err := netlink.FilterAdd(filter); err != nil { + e.Close() + return fmt.Errorf("cannot attach ebpf object to filter: %w", err) + } + + e.filter = filter + + return nil +} + +func (e *EBpfTC) Close() { + if e.filter != nil { + _ = netlink.FilterDel(e.filter) + } + if e.qdisc != nil { + _ = netlink.QdiscDel(e.qdisc) + } + if e.objs != nil { + _ = e.objs.Close() + } + _ = os.Remove(filepath.Join(e.bpfPath, "tc_params_map")) +} + +func (e *EBpfTC) Lookup(_ netip.AddrPort) (socks5.Addr, error) { + return nil, fmt.Errorf("not supported") +} diff --git a/config/config.go b/config/config.go index 49a2c4261..882a2de8d 100644 --- a/config/config.go +++ b/config/config.go @@ -55,6 +55,7 @@ type General struct { EnableProcess bool `json:"enable-process"` Tun Tun `json:"tun"` Sniffing bool `json:"sniffing"` + EBpf EBpf `json:"-"` } // Inbound config @@ -190,6 +191,7 @@ type RawTun struct { DNSHijack []string `yaml:"dns-hijack" json:"dns-hijack"` AutoRoute bool `yaml:"auto-route" json:"auto-route"` AutoDetectInterface bool `yaml:"auto-detect-interface"` + RedirectToTun []string `yaml:"-" json:"-"` } type RawConfig struct { @@ -222,6 +224,7 @@ type RawConfig struct { Hosts map[string]string `yaml:"hosts"` DNS RawDNS `yaml:"dns"` Tun RawTun `yaml:"tun"` + EBpf EBpf `yaml:"ebpf"` IPTables IPTables `yaml:"iptables"` Experimental Experimental `yaml:"experimental"` Profile Profile `yaml:"profile"` @@ -245,6 +248,12 @@ type RawSniffer struct { Ports []string `yaml:"port-whitelist" json:"port-whitelist"` } +// EBpf config +type EBpf struct { + RedirectToTun []string `yaml:"redirect-to-tun" json:"redirect-to-tun"` + AutoRedir []string `yaml:"auto-redir" json:"auto-redir"` +} + var ( GroupsList = list.New() ProxiesList = list.New() @@ -415,7 +424,7 @@ func parseGeneral(cfg *RawConfig) (*General, error) { return nil, fmt.Errorf("external-ui: %s not exist", externalUI) } } - + cfg.Tun.RedirectToTun = cfg.EBpf.RedirectToTun return &General{ Inbound: Inbound{ Port: cfg.Port, @@ -442,6 +451,7 @@ func parseGeneral(cfg *RawConfig) (*General, error) { GeodataLoader: cfg.GeodataLoader, TCPConcurrent: cfg.TCPConcurrent, EnableProcess: cfg.EnableProcess, + EBpf: cfg.EBpf, }, nil } diff --git a/constant/ebpf.go b/constant/ebpf.go new file mode 100644 index 000000000..b722dce14 --- /dev/null +++ b/constant/ebpf.go @@ -0,0 +1,20 @@ +package constant + +import ( + "net/netip" + + "github.com/Dreamacro/clash/transport/socks5" +) + +const ( + BpfFSPath = "/sys/fs/bpf/clash" + + TcpAutoRedirPort = 't'<<8 | 'r'<<0 + ClashTrafficMark = 'c'<<24 | 'l'<<16 | 't'<<8 | 'm'<<0 +) + +type EBpf interface { + Start() error + Close() + Lookup(srcAddrPort netip.AddrPort) (socks5.Addr, error) +} diff --git a/docs/config.yaml b/docs/config.yaml index 3ae67c94a..2f77a53b1 100644 --- a/docs/config.yaml +++ b/docs/config.yaml @@ -46,6 +46,13 @@ tun: # auto-detect-interface: true # 自动识别interface # auto-route: true # 配置 +#ebpf配置 +ebpf: + auto-redir: #redirect模式，仅支持TCP + - eth0 + redirect-to-tun: #UDP+TCP,使用该功能请勿启用auto-route + - eth0 + # 嗅探域名 可选配置 sniffer: enable: false diff --git a/go.mod b/go.mod index 144abfd10..16995566a 100644 --- a/go.mod +++ b/go.mod @@ -47,12 +47,13 @@ replace github.com/lucas-clemente/quic-go => github.com/tobyxdd/quic-go v0.28.1- require ( github.com/cheekybits/genny v1.0.0 // indirect + github.com/cilium/ebpf v0.9.1 // indirect github.com/davecgh/go-spew v1.1.1 // indirect github.com/fsnotify/fsnotify v1.5.4 // indirect github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0 // indirect github.com/google/btree v1.0.1 // indirect github.com/klauspost/cpuid/v2 v2.0.12 // indirect - github.com/kr/pretty v0.2.1 // indirect + github.com/kr/pretty v0.3.0 // indirect github.com/marten-seemann/qpack v0.2.1 // indirect github.com/marten-seemann/qtls-go1-16 v0.1.5 // indirect github.com/marten-seemann/qtls-go1-17 v0.1.2 // indirect diff --git a/go.sum b/go.sum index 131576c46..7c77ae3b9 100644 --- a/go.sum +++ b/go.sum @@ -16,10 +16,13 @@ github.com/bradfitz/go-smtpd v0.0.0-20170404230938-deb6d6237625/go.mod h1:HYsPBT github.com/buger/jsonparser v0.0.0-20181115193947-bf1c66bbce23/go.mod h1:bbYlZJ7hK1yFx9hf58LP0zeX7UjIGs20ufpu3evjr+s= github.com/cheekybits/genny v1.0.0 h1:uGGa4nei+j20rOSeDeP5Of12XVm7TGUd4dJA9RDitfE= github.com/cheekybits/genny v1.0.0/go.mod h1:+tQajlRqAUrPI7DOSpB0XAqZYtQakVtB7wXkRAgjxjQ= +github.com/cilium/ebpf v0.9.1 h1:64sn2K3UKw8NbP/blsixRpF3nXuyhz/VjRlRzvlBRu4= +github.com/cilium/ebpf v0.9.1/go.mod h1:+OhNOIXx/Fnu1IE8bJz2dzOA+VSfyTfdNUVdlQnxUFY= github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw= github.com/coreos/go-iptables v0.6.0 h1:is9qnZMPYjLd8LYqmm/qlE+wwEgJIkTYdhV3rfZo4jk= github.com/coreos/go-iptables v0.6.0/go.mod h1:Qe8Bv2Xik5FyTXwgIbLAnv2sWSBmvWdFETJConOQ//Q= github.com/coreos/go-systemd v0.0.0-20181012123002-c6f51f82210d/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4= +github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E= github.com/database64128/tfo-go v1.1.0 h1:VO0polyGNSAmr99nYw9GQeMz7ZOcQ/QbjlTwniHwfTQ= github.com/database64128/tfo-go v1.1.0/go.mod h1:95pOT8bnV3P2Lmu9upHNWFHz6dYGJ9cr7pnb0tGQAG8= github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38= @@ -111,10 +114,14 @@ github.com/klauspost/cpuid/v2 v2.0.12/go.mod h1:g2LTdtYhdyuGPqyWyv7qRAmj1WBqxuOb github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo= github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI= github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI= +github.com/kr/pretty v0.3.0 h1:WgNl7dwNpEZ6jJ9k1snq4pZsg7DOEN8hP9Xw0Tsjwk0= +github.com/kr/pretty v0.3.0/go.mod h1:640gp4NfQd8pI5XOwp5fnNeVWj67G7CFk/SaSQn7NBk= github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ= github.com/kr/pty v1.1.3/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ= github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE= github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI= +github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY= +github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE= github.com/lunixbochs/struc v0.0.0-20200707160740-784aaebc1d40 h1:EnfXoSqDfSNJv0VBNqY/88RNnhSGYkrHaO0mmFGbVsc= github.com/lunixbochs/struc v0.0.0-20200707160740-784aaebc1d40/go.mod h1:vy1vK6wD6j7xX6O6hXe621WabdtNkou2h7uRtTfRMyg= github.com/lunixbochs/vtclean v1.0.0/go.mod h1:pHhQNgMf3btfWnGBVipUOjRYhoOsdGqdm/+2c2E2WMI= @@ -171,6 +178,7 @@ github.com/prometheus/client_golang v0.8.0/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXP github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910/go.mod h1:MbSGuTsp3dbXC40dX6PRTWyKYBIrTGTE9sqQNg2J8bo= github.com/prometheus/common v0.0.0-20180801064454-c7de2306084e/go.mod h1:daVV7qP5qjZbuso7PdcryaAu0sAZbrN9i7WWcTMWvro= github.com/prometheus/procfs v0.0.0-20180725123919-05ee40e3a273/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk= +github.com/rogpeppe/go-internal v1.6.1/go.mod h1:xXDCJY+GAPziupqXw64V24skbSoqbTEfhy4qGm1nDQc= github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g= github.com/sagernet/sing v0.0.0-20220627234642-a817f7084d9c h1:98QC0wtaD648MFPw82KaT1O9LloQgR4ZyIDtNtsno8Y= github.com/sagernet/sing v0.0.0-20220627234642-a817f7084d9c/go.mod h1:I67R/q5f67xDExL2kL3RLIP7kGJBOPkYXkpRAykgC+E= @@ -406,6 +414,7 @@ gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0= gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo= gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0= +gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI= gopkg.in/fsnotify.v1 v1.4.7/go.mod h1:Tz8NjZHkW78fSQdbUxIjBTcgA1z1m8ZHf0WmKUhAMys= gopkg.in/inf.v0 v0.9.1/go.mod h1:cWUDdTG/fYaXco+Dcufb5Vnc6Gp2YChqWtbxRZE0mXw= gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 h1:uRGJdciOHaEIrze2W8Q3AKkepLTh2hOroT7a+7czfdQ= diff --git a/hub/executor/executor.go b/hub/executor/executor.go index d4148dd86..a155bda72 100644 --- a/hub/executor/executor.go +++ b/hub/executor/executor.go @@ -334,6 +334,8 @@ func updateGeneral(general *config.General, force bool) { P.ReCreateRedir(general.RedirPort, tcpIn, udpIn) P.ReCreateTProxy(general.TProxyPort, tcpIn, udpIn) P.ReCreateMixed(general.MixedPort, tcpIn, udpIn) + P.ReCreateAutoRedir(general.EBpf.AutoRedir, tcpIn, udpIn) + P.ReCreateRedirToTun(general.EBpf.RedirectToTun) } func updateUsers(users []auth.AuthUser) { diff --git a/listener/autoredir/tcp.go b/listener/autoredir/tcp.go new file mode 100644 index 000000000..efcd668bc --- /dev/null +++ b/listener/autoredir/tcp.go @@ -0,0 +1,86 @@ +package autoredir + +import ( + "net" + "net/netip" + + "github.com/Dreamacro/clash/adapter/inbound" + C "github.com/Dreamacro/clash/constant" + "github.com/Dreamacro/clash/log" + "github.com/Dreamacro/clash/transport/socks5" +) + +type Listener struct { + listener net.Listener + addr string + closed bool + lookupFunc func(netip.AddrPort) (socks5.Addr, error) +} + +// RawAddress implements C.Listener +func (l *Listener) RawAddress() string { + return l.addr +} + +// Address implements C.Listener +func (l *Listener) Address() string { + return l.listener.Addr().String() +} + +// Close implements C.Listener +func (l *Listener) Close() error { + l.closed = true + return l.listener.Close() +} + +func (l *Listener) TCPAddr() netip.AddrPort { + return l.listener.Addr().(*net.TCPAddr).AddrPort() +} + +func (l *Listener) SetLookupFunc(lookupFunc func(netip.AddrPort) (socks5.Addr, error)) { + l.lookupFunc = lookupFunc +} + +func (l *Listener) handleRedir(conn net.Conn, in chan<- C.ConnContext) { + if l.lookupFunc == nil { + log.Errorln("[Auto Redirect] lookup function is nil") + return + } + + target, err := l.lookupFunc(conn.RemoteAddr().(*net.TCPAddr).AddrPort()) + if err != nil { + log.Warnln("[Auto Redirect] %v", err) + _ = conn.Close() + return + } + + _ = conn.(*net.TCPConn).SetKeepAlive(true) + + in <- inbound.NewSocket(target, conn, C.REDIR) +} + +func New(addr string, in chan<- C.ConnContext) (*Listener, error) { + l, err := net.Listen("tcp", addr) + if err != nil { + return nil, err + } + rl := &Listener{ + listener: l, + addr: addr, + } + + go func() { + for { + c, err := l.Accept() + if err != nil { + if rl.closed { + break + } + continue + } + go rl.handleRedir(c, in) + } + }() + + return rl, nil +} diff --git a/listener/listener.go b/listener/listener.go index 0dc3a3167..79b60e5e4 100644 --- a/listener/listener.go +++ b/listener/listener.go @@ -2,8 +2,11 @@ package proxy import ( "fmt" + "github.com/Dreamacro/clash/component/ebpf" + "github.com/Dreamacro/clash/listener/autoredir" "github.com/Dreamacro/clash/listener/inner" "github.com/Dreamacro/clash/listener/tun/ipstack/commons" + "golang.org/x/exp/slices" "net" "sort" "strconv" @@ -38,14 +41,19 @@ var ( mixedListener *mixed.Listener mixedUDPLister *socks.UDPListener tunStackListener ipstack.Stack + tcProgram *ebpf.TcEBpfProgram + autoRedirListener *autoredir.Listener + autoRedirProgram *ebpf.TcEBpfProgram // lock for recreate function - socksMux sync.Mutex - httpMux sync.Mutex - redirMux sync.Mutex - tproxyMux sync.Mutex - mixedMux sync.Mutex - tunMux sync.Mutex + socksMux sync.Mutex + httpMux sync.Mutex + redirMux sync.Mutex + tproxyMux sync.Mutex + mixedMux sync.Mutex + tunMux sync.Mutex + autoRedirMux sync.Mutex + tcMux sync.Mutex ) type Ports struct { @@ -356,6 +364,93 @@ func ReCreateTun(tunConf *config.Tun, tcpIn chan<- C.ConnContext, udpIn chan<- * lastTunConf = tunConf } +func ReCreateAutoRedir(ifaceNames []string, tcpIn chan<- C.ConnContext, _ chan<- *inbound.PacketAdapter) { + autoRedirMux.Lock() + defer autoRedirMux.Unlock() + + var err error + defer func() { + if err != nil { + if redirListener != nil { + _ = redirListener.Close() + redirListener = nil + } + if autoRedirProgram != nil { + autoRedirProgram.Close() + autoRedirProgram = nil + } + log.Errorln("Start auto redirect server error: %s", err.Error()) + } + }() + + nicArr := ifaceNames + slices.Sort(nicArr) + nicArr = slices.Compact(nicArr) + + if redirListener != nil && autoRedirProgram != nil { + _ = redirListener.Close() + autoRedirProgram.Close() + redirListener = nil + autoRedirProgram = nil + } + + if len(nicArr) == 0 { + return + } + + defaultRouteInterfaceName, err := commons.GetAutoDetectInterface() + if err != nil { + return + } + + addr := genAddr("*", C.TcpAutoRedirPort, true) + + autoRedirListener, err = autoredir.New(addr, tcpIn) + if err != nil { + return + } + + autoRedirProgram, err = ebpf.NewRedirEBpfProgram(nicArr, autoRedirListener.TCPAddr().Port(), defaultRouteInterfaceName) + if err != nil { + return + } + + autoRedirListener.SetLookupFunc(autoRedirProgram.Lookup) + + log.Infoln("Auto redirect proxy listening at: %s, attached tc ebpf program to interfaces %v", autoRedirListener.Address(), autoRedirProgram.RawNICs()) +} + +func ReCreateRedirToTun(ifaceNames []string) { + tcMux.Lock() + defer tcMux.Unlock() + + nicArr := ifaceNames + slices.Sort(nicArr) + nicArr = slices.Compact(nicArr) + + if tcProgram != nil { + tcProgram.Close() + tcProgram = nil + } + + if len(nicArr) == 0 { + return + } + + if lastTunConf == nil || !lastTunConf.Enable { + return + } + + program, err := ebpf.NewTcEBpfProgram(nicArr, lastTunConf.Device) + if err != nil { + log.Errorln("Attached tc ebpf program error: %v", err) + return + } + tcProgram = program + + log.Infoln("Attached tc ebpf program to interfaces %v", tcProgram.RawNICs()) +} + // GetPorts return the ports of proxy servers func GetPorts() *Ports { ports := &Ports{}