72 lines
1.3 KiB
Go
72 lines
1.3 KiB
Go
package obfs
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"hash/crc32"
|
|
"math/rand"
|
|
"net"
|
|
|
|
"github.com/Dreamacro/clash/common/pool"
|
|
)
|
|
|
|
func init() {
|
|
register("random_head", newRandomHead, 0)
|
|
}
|
|
|
|
type randomHead struct {
|
|
*Base
|
|
}
|
|
|
|
func newRandomHead(b *Base) Obfs {
|
|
return &randomHead{Base: b}
|
|
}
|
|
|
|
type randomHeadConn struct {
|
|
net.Conn
|
|
*randomHead
|
|
hasSentHeader bool
|
|
rawTransSent bool
|
|
rawTransRecv bool
|
|
buf []byte
|
|
}
|
|
|
|
func (r *randomHead) StreamConn(c net.Conn) net.Conn {
|
|
return &randomHeadConn{Conn: c, randomHead: r}
|
|
}
|
|
|
|
func (c *randomHeadConn) Read(b []byte) (int, error) {
|
|
if c.rawTransRecv {
|
|
return c.Conn.Read(b)
|
|
}
|
|
buf := pool.Get(pool.RelayBufferSize)
|
|
defer pool.Put(buf)
|
|
c.Conn.Read(buf)
|
|
c.rawTransRecv = true
|
|
c.Write(nil)
|
|
return 0, nil
|
|
}
|
|
|
|
func (c *randomHeadConn) Write(b []byte) (int, error) {
|
|
if c.rawTransSent {
|
|
return c.Conn.Write(b)
|
|
}
|
|
c.buf = append(c.buf, b...)
|
|
if !c.hasSentHeader {
|
|
c.hasSentHeader = true
|
|
dataLength := rand.Intn(96) + 4
|
|
buf := pool.Get(dataLength + 4)
|
|
defer pool.Put(buf)
|
|
rand.Read(buf[:dataLength])
|
|
binary.LittleEndian.PutUint32(buf[dataLength:], 0xffffffff-crc32.ChecksumIEEE(buf[:dataLength]))
|
|
_, err := c.Conn.Write(buf)
|
|
return len(b), err
|
|
}
|
|
if c.rawTransRecv {
|
|
_, err := c.Conn.Write(c.buf)
|
|
c.buf = nil
|
|
c.rawTransSent = true
|
|
return len(b), err
|
|
}
|
|
return len(b), nil
|
|
}
|