clash/transport/hysteria/conns/wechat/obfs.go
2022-08-15 15:46:07 +08:00

97 lines
2.1 KiB
Go

package wechat
import (
"encoding/binary"
"github.com/Dreamacro/clash/log"
"github.com/Dreamacro/clash/transport/hysteria/obfs"
"math/rand"
"net"
"sync"
"time"
)
const udpBufferSize = 65535
type ObfsWeChatUDPConn struct {
orig net.PacketConn
obfs obfs.Obfuscator
readBuf []byte
readMutex sync.Mutex
writeBuf []byte
writeMutex sync.Mutex
sn uint32
}
func NewObfsWeChatUDPConn(orig net.PacketConn, obfs obfs.Obfuscator) *ObfsWeChatUDPConn {
log.Infoln("new wechat")
return &ObfsWeChatUDPConn{
orig: orig,
obfs: obfs,
readBuf: make([]byte, udpBufferSize),
writeBuf: make([]byte, udpBufferSize),
sn: rand.Uint32() & 0xFFFF,
}
}
func (c *ObfsWeChatUDPConn) ReadFrom(p []byte) (int, net.Addr, error) {
for {
c.readMutex.Lock()
n, addr, err := c.orig.ReadFrom(c.readBuf)
if n <= 13 {
c.readMutex.Unlock()
return 0, addr, err
}
newN := c.obfs.Deobfuscate(c.readBuf[13:n], p)
c.readMutex.Unlock()
if newN > 0 {
// Valid packet
return newN, addr, err
} else if err != nil {
// Not valid and orig.ReadFrom had some error
return 0, addr, err
}
}
}
func (c *ObfsWeChatUDPConn) WriteTo(p []byte, addr net.Addr) (n int, err error) {
c.writeMutex.Lock()
c.writeBuf[0] = 0xa1
c.writeBuf[1] = 0x08
binary.BigEndian.PutUint32(c.writeBuf[2:], c.sn)
c.sn++
c.writeBuf[6] = 0x00
c.writeBuf[7] = 0x10
c.writeBuf[8] = 0x11
c.writeBuf[9] = 0x18
c.writeBuf[10] = 0x30
c.writeBuf[11] = 0x22
c.writeBuf[12] = 0x30
bn := c.obfs.Obfuscate(p, c.writeBuf[13:])
_, err = c.orig.WriteTo(c.writeBuf[:13+bn], addr)
c.writeMutex.Unlock()
if err != nil {
return 0, err
} else {
return len(p), nil
}
}
func (c *ObfsWeChatUDPConn) Close() error {
return c.orig.Close()
}
func (c *ObfsWeChatUDPConn) LocalAddr() net.Addr {
return c.orig.LocalAddr()
}
func (c *ObfsWeChatUDPConn) SetDeadline(t time.Time) error {
return c.orig.SetDeadline(t)
}
func (c *ObfsWeChatUDPConn) SetReadDeadline(t time.Time) error {
return c.orig.SetReadDeadline(t)
}
func (c *ObfsWeChatUDPConn) SetWriteDeadline(t time.Time) error {
return c.orig.SetWriteDeadline(t)
}