122 lines
2.6 KiB
Go
122 lines
2.6 KiB
Go
|
package dns
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"net"
|
||
|
|
"strings"
|
||
|
|
|
||
|
|
"github.com/Dreamacro/clash/common/cache"
|
||
|
|
"github.com/Dreamacro/clash/component/fakeip"
|
||
|
|
"github.com/Dreamacro/clash/log"
|
||
|
|
|
||
|
|
D "github.com/miekg/dns"
|
||
|
|
)
|
||
|
|
|
||
|
|
type handler func(w D.ResponseWriter, r *D.Msg)
|
||
|
|
|
||
|
|
func withFakeIP(cache *cache.Cache, pool *fakeip.Pool) handler {
|
||
|
|
return func(w D.ResponseWriter, r *D.Msg) {
|
||
|
|
q := r.Question[0]
|
||
|
|
|
||
|
|
cacheItem := cache.Get("fakeip:" + q.String())
|
||
|
|
if cache != nil {
|
||
|
|
msg := cacheItem.(*D.Msg).Copy()
|
||
|
|
setMsgTTL(msg, 1)
|
||
|
|
msg.SetReply(r)
|
||
|
|
w.WriteMsg(msg)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
rr := &D.A{}
|
||
|
|
rr.Hdr = D.RR_Header{Name: q.Name, Rrtype: D.TypeA, Class: D.ClassINET, Ttl: dnsDefaultTTL}
|
||
|
|
ip := pool.Get()
|
||
|
|
rr.A = ip
|
||
|
|
msg := r.Copy()
|
||
|
|
msg.Answer = []D.RR{rr}
|
||
|
|
putMsgToCache(cache, "fakeip:"+q.String(), msg)
|
||
|
|
putMsgToCache(cache, ip.String(), msg)
|
||
|
|
|
||
|
|
setMsgTTL(msg, 1)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func withResolver(resolver *Resolver) handler {
|
||
|
|
return func(w D.ResponseWriter, r *D.Msg) {
|
||
|
|
msg, err := resolver.Exchange(r)
|
||
|
|
|
||
|
|
if err != nil {
|
||
|
|
q := r.Question[0]
|
||
|
|
qString := fmt.Sprintf("%s %s %s", q.Name, D.Class(q.Qclass).String(), D.Type(q.Qtype).String())
|
||
|
|
log.Debugln("[DNS Server] Exchange %s failed: %v", qString, err)
|
||
|
|
D.HandleFailed(w, r)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
msg.SetReply(r)
|
||
|
|
w.WriteMsg(msg)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func withHost(resolver *Resolver, next handler) handler {
|
||
|
|
hosts := resolver.hosts
|
||
|
|
if hosts == nil {
|
||
|
|
panic("dns/withHost: hosts should not be nil")
|
||
|
|
}
|
||
|
|
|
||
|
|
return func(w D.ResponseWriter, r *D.Msg) {
|
||
|
|
q := r.Question[0]
|
||
|
|
if q.Qtype != D.TypeA && q.Qtype != D.TypeAAAA {
|
||
|
|
next(w, r)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
domain := strings.TrimRight(q.Name, ".")
|
||
|
|
host := hosts.Search(domain)
|
||
|
|
if host == nil {
|
||
|
|
next(w, r)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
ip := host.Data.(net.IP)
|
||
|
|
if q.Qtype == D.TypeAAAA && ip.To16() == nil {
|
||
|
|
next(w, r)
|
||
|
|
return
|
||
|
|
} else if q.Qtype == D.TypeA && ip.To4() == nil {
|
||
|
|
next(w, r)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
var rr D.RR
|
||
|
|
if q.Qtype == D.TypeAAAA {
|
||
|
|
record := &D.AAAA{}
|
||
|
|
record.Hdr = D.RR_Header{Name: q.Name, Rrtype: D.TypeAAAA, Class: D.ClassINET, Ttl: dnsDefaultTTL}
|
||
|
|
record.AAAA = ip
|
||
|
|
rr = record
|
||
|
|
} else {
|
||
|
|
record := &D.A{}
|
||
|
|
record.Hdr = D.RR_Header{Name: q.Name, Rrtype: D.TypeA, Class: D.ClassINET, Ttl: dnsDefaultTTL}
|
||
|
|
record.A = ip
|
||
|
|
rr = record
|
||
|
|
}
|
||
|
|
|
||
|
|
msg := r.Copy()
|
||
|
|
msg.Answer = []D.RR{rr}
|
||
|
|
msg.SetReply(r)
|
||
|
|
w.WriteMsg(msg)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func newHandler(resolver *Resolver) handler {
|
||
|
|
if resolver.IsFakeIP() {
|
||
|
|
return withFakeIP(resolver.cache, resolver.pool)
|
||
|
|
}
|
||
|
|
|
||
|
|
if resolver.hosts != nil {
|
||
|
|
return withHost(resolver, withResolver(resolver))
|
||
|
|
}
|
||
|
|
|
||
|
|
return withResolver(resolver)
|
||
|
|
}
|