Clash.Meta/component/trie/domain.go
2021-11-25 23:14:31 +08:00

422 lines
8.1 KiB
Go

package trie
import (
"errors"
"github.com/Dreamacro/clash/log"
"net"
"strings"
)
const (
wildcard = "*"
dotWildcard = ""
complexWildcard = "+"
domainStep = "."
)
// ErrInvalidDomain means insert domain is invalid
var ErrInvalidDomain = errors.New("invalid domain")
// DomainTrie contains the main logic for adding and searching nodes for domain segments.
// support wildcard domain (e.g *.google.com)
type DomainTrie struct {
root *Node
}
func ValidAndSplitDomain(domain string) ([]string, bool) {
if domain != "" && domain[len(domain)-1] == '.' {
return nil, false
}
parts := strings.Split(domain, domainStep)
if len(parts) == 1 {
if parts[0] == "" {
return nil, false
}
return parts, true
}
for _, part := range parts[1:] {
if part == "" {
return nil, false
}
}
return parts, true
}
// Insert adds a node to the trie.
// Support
// 1. www.example.com
// 2. *.example.com
// 3. subdomain.*.example.com
// 4. .example.com
// 5. +.example.com
func (t *DomainTrie) Insert(domain string, data interface{}) error {
parts, valid := ValidAndSplitDomain(domain)
if !valid {
return ErrInvalidDomain
}
if parts[0] == complexWildcard {
t.insert(parts[1:], data)
parts[0] = dotWildcard
t.insert(parts, data)
} else {
t.insert(parts, data)
}
return nil
}
func (t *DomainTrie) insert(parts []string, data interface{}) {
node := t.root
// reverse storage domain part to save space
for i := len(parts) - 1; i >= 0; i-- {
part := parts[i]
if !node.hasChild(part) {
node.addChild(part, newNode(nil))
}
node = node.getChild(part)
}
node.Data = data
}
// Search is the most important part of the Trie.
// Priority as:
// 1. static part
// 2. wildcard domain
// 2. dot wildcard domain
func (t *DomainTrie) Search(domain string) *Node {
parts, valid := ValidAndSplitDomain(domain)
if !valid || parts[0] == "" {
return nil
}
n := t.search(t.root, parts)
if n == nil || n.Data == nil {
return nil
}
return n
}
func (t *DomainTrie) search(node *Node, parts []string) *Node {
if len(parts) == 0 {
return node
}
if c := node.getChild(parts[len(parts)-1]); c != nil {
if n := t.search(c, parts[:len(parts)-1]); n != nil {
return n
}
}
if c := node.getChild(wildcard); c != nil {
if n := t.search(c, parts[:len(parts)-1]); n != nil {
return n
}
}
return node.getChild(dotWildcard)
}
// New returns a new, empty Trie.
func New() *DomainTrie {
return &DomainTrie{root: newNode(nil)}
}
type IPV6 bool
const (
ipv4GroupMaxValue = 0xFF
ipv6GroupMaxValue = 0xFFFF
)
type IpCidrTrie struct {
ipv4Trie *IpCidrNode
ipv6Trie *IpCidrNode
}
func NewIpCidrTrie() *IpCidrTrie {
return &IpCidrTrie{
ipv4Trie: NewIpCidrNode(false, ipv4GroupMaxValue),
ipv6Trie: NewIpCidrNode(false, ipv6GroupMaxValue),
}
}
func (trie *IpCidrTrie) AddIpCidr(ipCidr *net.IPNet) error {
subIpCidr, subCidr, isIpv4, err := ipCidrToSubIpCidr(ipCidr)
if err != nil {
return err
}
for _, sub := range subIpCidr {
addIpCidr(trie, isIpv4, sub, subCidr/8)
}
return nil
}
func (trie *IpCidrTrie) AddIpCidrForString(ipCidr string) error {
_, ipNet, err := net.ParseCIDR(ipCidr)
if err != nil {
return err
}
return trie.AddIpCidr(ipNet)
}
func (trie *IpCidrTrie) IsContain(ip net.IP) bool {
ip, isIpv4 := checkAndConverterIp(ip)
if ip == nil {
return false
}
var groupValues []uint32
var ipCidrNode *IpCidrNode
if isIpv4 {
ipCidrNode = trie.ipv4Trie
for _, group := range ip {
groupValues = append(groupValues, uint32(group))
}
} else {
ipCidrNode = trie.ipv6Trie
for i := 0; i < len(ip); i += 2 {
groupValues = append(groupValues, getIpv6GroupValue(ip[i], ip[i+1]))
}
}
return search(ipCidrNode, groupValues) != nil
}
func (trie *IpCidrTrie) IsContainForString(ipString string) bool {
return trie.IsContain(net.ParseIP(ipString))
}
func ipCidrToSubIpCidr(ipNet *net.IPNet) ([]net.IP, int, bool, error) {
maskSize, _ := ipNet.Mask.Size()
var (
ipList []net.IP
newMaskSize int
isIpv4 bool
err error
)
ip, isIpv4 := checkAndConverterIp(ipNet.IP)
ipList, newMaskSize, err = subIpCidr(ip, maskSize, isIpv4)
return ipList, newMaskSize, isIpv4, err
}
func subIpCidr(ip net.IP, maskSize int, isIpv4 bool) ([]net.IP, int, error) {
var subIpCidrList []net.IP
groupSize := 8
if !isIpv4 {
groupSize = 16
}
if maskSize%groupSize == 0 {
return append(subIpCidrList, ip), maskSize, nil
}
lastByteMaskSize := maskSize % 8
lastByteMaskIndex := maskSize / 8
subIpCidrNum := 0xFF >> lastByteMaskSize
for i := 0; i < subIpCidrNum; i++ {
subIpCidr := make([]byte, len(ip))
copy(subIpCidr, ip)
subIpCidr[lastByteMaskIndex] += byte(i)
subIpCidrList = append(subIpCidrList, subIpCidr)
}
newMaskSize := (lastByteMaskIndex + 1) * 8
if !isIpv4 {
newMaskSize = (lastByteMaskIndex/2 + 1) * 16
}
return subIpCidrList, newMaskSize, nil
}
func addIpCidr(trie *IpCidrTrie, isIpv4 bool, ip net.IP, groupSize int) {
if isIpv4 {
addIpv4Cidr(trie, ip, groupSize)
} else {
addIpv6Cidr(trie, ip, groupSize)
}
}
func addIpv4Cidr(trie *IpCidrTrie, ip net.IP, groupSize int) {
preNode := trie.ipv4Trie
node := preNode.getChild(uint32(ip[0]))
if node == nil {
err := preNode.addChild(uint32(ip[0]))
if err != nil {
return
}
node = preNode.getChild(uint32(ip[0]))
}
for i := 1; i < groupSize; i++ {
if node.Mark {
return
}
groupValue := uint32(ip[i])
if !node.hasChild(groupValue) {
err := node.addChild(groupValue)
if err != nil {
log.Errorln(err.Error())
}
}
preNode = node
node = node.getChild(groupValue)
if node == nil {
err := preNode.addChild(uint32(ip[i-1]))
if err != nil {
return
}
node = preNode.getChild(uint32(ip[i-1]))
}
}
node.Mark = true
cleanChild(node)
}
func addIpv6Cidr(trie *IpCidrTrie, ip net.IP, groupSize int) {
preNode := trie.ipv6Trie
node := preNode.getChild(getIpv6GroupValue(ip[0], ip[1]))
if node == nil {
err := preNode.addChild(getIpv6GroupValue(ip[0], ip[1]))
if err != nil {
return
}
node = preNode.getChild(getIpv6GroupValue(ip[0], ip[1]))
}
for i := 2; i < groupSize; i += 2 {
if node.Mark {
return
}
groupValue := getIpv6GroupValue(ip[i], ip[i+1])
if !node.hasChild(groupValue) {
err := node.addChild(groupValue)
if err != nil {
log.Errorln(err.Error())
}
}
preNode = node
node = node.getChild(groupValue)
if node == nil {
err := preNode.addChild(getIpv6GroupValue(ip[i-2], ip[i-1]))
if err != nil {
return
}
node = preNode.getChild(getIpv6GroupValue(ip[i-2], ip[i-1]))
}
}
node.Mark = true
cleanChild(node)
}
func getIpv6GroupValue(high, low byte) uint32 {
return (uint32(high) << 8) | uint32(low)
}
func cleanChild(node *IpCidrNode) {
for i := uint32(0); i < uint32(len(node.child)); i++ {
delete(node.child, i)
}
}
func search(root *IpCidrNode, groupValues []uint32) *IpCidrNode {
node := root.getChild(groupValues[0])
if node == nil || node.Mark {
return node
}
for _, value := range groupValues[1:] {
if !node.hasChild(value) {
return nil
}
node = node.getChild(value)
if node == nil || node.Mark {
return node
}
}
return nil
}
// return net.IP To4 or To16 and is ipv4
func checkAndConverterIp(ip net.IP) (net.IP, bool) {
ipResult := ip.To4()
if ipResult == nil {
ipResult = ip.To16()
if ipResult == nil {
return nil, false
}
return ipResult, false
}
return ipResult, true
}
var (
ErrorOverMaxValue = errors.New("the value don't over max value")
)
type IpCidrNode struct {
Mark bool
child map[uint32]*IpCidrNode
maxValue uint32
}
func NewIpCidrNode(mark bool, maxValue uint32) *IpCidrNode {
ipCidrNode := &IpCidrNode{
Mark: mark,
child: map[uint32]*IpCidrNode{},
maxValue: maxValue,
}
return ipCidrNode
}
func (n *IpCidrNode) addChild(value uint32) error {
if value > n.maxValue {
return ErrorOverMaxValue
}
n.child[value] = NewIpCidrNode(false, n.maxValue)
return nil
}
func (n *IpCidrNode) hasChild(value uint32) bool {
return n.getChild(value) != nil
}
func (n *IpCidrNode) getChild(value uint32) *IpCidrNode {
if value <= n.maxValue {
return n.child[value]
}
return nil
}