72 lines
1.4 KiB
Go
72 lines
1.4 KiB
Go
package obfs
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import (
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"encoding/binary"
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"hash/crc32"
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"net"
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"github.com/Dreamacro/clash/common/pool"
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"github.com/zhangyunhao116/fastrand"
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)
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func init() {
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register("random_head", newRandomHead, 0)
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}
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type randomHead struct {
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*Base
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}
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func newRandomHead(b *Base) Obfs {
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return &randomHead{Base: b}
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}
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type randomHeadConn struct {
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net.Conn
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*randomHead
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hasSentHeader bool
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rawTransSent bool
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rawTransRecv bool
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buf []byte
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}
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func (r *randomHead) StreamConn(c net.Conn) net.Conn {
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return &randomHeadConn{Conn: c, randomHead: r}
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}
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func (c *randomHeadConn) Read(b []byte) (int, error) {
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if c.rawTransRecv {
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return c.Conn.Read(b)
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}
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buf := pool.Get(pool.RelayBufferSize)
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defer pool.Put(buf)
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c.Conn.Read(buf)
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c.rawTransRecv = true
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c.Write(nil)
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return 0, nil
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}
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func (c *randomHeadConn) Write(b []byte) (int, error) {
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if c.rawTransSent {
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return c.Conn.Write(b)
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}
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c.buf = append(c.buf, b...)
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if !c.hasSentHeader {
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c.hasSentHeader = true
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dataLength := fastrand.Intn(96) + 4
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buf := pool.Get(dataLength + 4)
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defer pool.Put(buf)
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fastrand.Read(buf[:dataLength])
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binary.LittleEndian.PutUint32(buf[dataLength:], 0xffffffff-crc32.ChecksumIEEE(buf[:dataLength]))
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_, err := c.Conn.Write(buf)
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return len(b), err
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}
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if c.rawTransRecv {
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_, err := c.Conn.Write(c.buf)
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c.buf = nil
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c.rawTransSent = true
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return len(b), err
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}
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return len(b), nil
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}
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