mirror of
https://gitclone.com/github.com/MetaCubeX/Clash.Meta
synced 2024-11-16 06:01:21 +08:00
343 lines
8.6 KiB
C
343 lines
8.6 KiB
C
|
#include <stdint.h>
|
||
|
|
#include <stdbool.h>
|
||
|
|
//#include <linux/types.h>
|
||
|
|
|
||
|
|
#include <linux/bpf.h>
|
||
|
|
#include <linux/if_ether.h>
|
||
|
|
//#include <linux/if_packet.h>
|
||
|
|
//#include <linux/if_vlan.h>
|
||
|
|
#include <linux/ip.h>
|
||
|
|
#include <linux/in.h>
|
||
|
|
#include <linux/tcp.h>
|
||
|
|
//#include <linux/udp.h>
|
||
|
|
|
||
|
|
#include <linux/pkt_cls.h>
|
||
|
|
|
||
|
|
#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";
|