package obfs import ( "bytes" "crypto/hmac" "encoding/binary" "fmt" "io" "log" "math/rand" "strings" "time" "github.com/Dreamacro/clash/common/pool" "github.com/Dreamacro/clash/component/ssr/tools" ) type tlsAuthData struct { localClientID [32]byte } type tls12Ticket struct { *Base *tlsAuthData handshakeStatus int sendSaver bytes.Buffer recvBuffer bytes.Buffer buffer bytes.Buffer } func init() { register("tls1.2_ticket_auth", newTLS12Ticket) register("tls1.2_ticket_fastauth", newTLS12Ticket) } func newTLS12Ticket(b *Base) Obfs { return &tls12Ticket{ Base: b, } } func (t *tls12Ticket) initForConn() Obfs { r := &tls12Ticket{ Base: t.Base, tlsAuthData: &tlsAuthData{}, } rand.Read(r.localClientID[:]) return r } func (t *tls12Ticket) GetObfsOverhead() int { return 5 } func (t *tls12Ticket) Decode(b []byte) ([]byte, bool, error) { if t.handshakeStatus == -1 { return b, false, nil } t.buffer.Reset() if t.handshakeStatus == 8 { t.recvBuffer.Write(b) for t.recvBuffer.Len() > 5 { var h [5]byte t.recvBuffer.Read(h[:]) if !bytes.Equal(h[:3], []byte{0x17, 0x3, 0x3}) { log.Println("incorrect magic number", h[:3], ", 0x170303 is expected") return nil, false, errTLS12TicketAuthIncorrectMagicNumber } size := int(binary.BigEndian.Uint16(h[3:5])) if t.recvBuffer.Len() < size { // 不够读,下回再读吧 unread := t.recvBuffer.Bytes() t.recvBuffer.Reset() t.recvBuffer.Write(h[:]) t.recvBuffer.Write(unread) break } d := pool.Get(size) t.recvBuffer.Read(d) t.buffer.Write(d) pool.Put(d) } return t.buffer.Bytes(), false, nil } if len(b) < 11+32+1+32 { return nil, false, errTLS12TicketAuthTooShortData } hash := t.hmacSHA1(b[11 : 11+22]) if !hmac.Equal(b[33:33+tools.HmacSHA1Len], hash) { return nil, false, errTLS12TicketAuthHMACError } return nil, true, nil } func (t *tls12Ticket) Encode(b []byte) ([]byte, error) { t.buffer.Reset() switch t.handshakeStatus { case 8: if len(b) < 1024 { d := []byte{0x17, 0x3, 0x3, 0, 0} binary.BigEndian.PutUint16(d[3:5], uint16(len(b)&0xFFFF)) t.buffer.Write(d) t.buffer.Write(b) return t.buffer.Bytes(), nil } start := 0 var l int for len(b)-start > 2048 { l = rand.Intn(4096) + 100 if l > len(b)-start { l = len(b) - start } packData(&t.buffer, b[start:start+l]) start += l } if len(b)-start > 0 { l = len(b) - start packData(&t.buffer, b[start:start+l]) } return t.buffer.Bytes(), nil case 1: if len(b) > 0 { if len(b) < 1024 { packData(&t.sendSaver, b) } else { start := 0 var l int for len(b)-start > 2048 { l = rand.Intn(4096) + 100 if l > len(b)-start { l = len(b) - start } packData(&t.buffer, b[start:start+l]) start += l } if len(b)-start > 0 { l = len(b) - start packData(&t.buffer, b[start:start+l]) } io.Copy(&t.sendSaver, &t.buffer) } return []byte{}, nil } hmacData := make([]byte, 43) handshakeFinish := []byte("\x14\x03\x03\x00\x01\x01\x16\x03\x03\x00\x20") copy(hmacData, handshakeFinish) rand.Read(hmacData[11:33]) h := t.hmacSHA1(hmacData[:33]) copy(hmacData[33:], h) t.buffer.Write(hmacData) io.Copy(&t.buffer, &t.sendSaver) t.handshakeStatus = 8 return t.buffer.Bytes(), nil case 0: tlsData0 := []byte("\x00\x1c\xc0\x2b\xc0\x2f\xcc\xa9\xcc\xa8\xcc\x14\xcc\x13\xc0\x0a\xc0\x14\xc0\x09\xc0\x13\x00\x9c\x00\x35\x00\x2f\x00\x0a\x01\x00") tlsData1 := []byte("\xff\x01\x00\x01\x00") tlsData2 := []byte("\x00\x17\x00\x00\x00\x23\x00\xd0") // tlsData3 := []byte("\x00\x0d\x00\x16\x00\x14\x06\x01\x06\x03\x05\x01\x05\x03\x04\x01\x04\x03\x03\x01\x03\x03\x02\x01\x02\x03\x00\x05\x00\x05\x01\x00\x00\x00\x00\x00\x12\x00\x00\x75\x50\x00\x00\x00\x0b\x00\x02\x01\x00\x00\x0a\x00\x06\x00\x04\x00\x17\x00\x18\x00\x15\x00\x66\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00") tlsData3 := []byte("\x00\x0d\x00\x16\x00\x14\x06\x01\x06\x03\x05\x01\x05\x03\x04\x01\x04\x03\x03\x01\x03\x03\x02\x01\x02\x03\x00\x05\x00\x05\x01\x00\x00\x00\x00\x00\x12\x00\x00\x75\x50\x00\x00\x00\x0b\x00\x02\x01\x00\x00\x0a\x00\x06\x00\x04\x00\x17\x00\x18") var tlsData [2048]byte tlsDataLen := 0 copy(tlsData[0:], tlsData1) tlsDataLen += len(tlsData1) sni := t.sni(t.getHost()) copy(tlsData[tlsDataLen:], sni) tlsDataLen += len(sni) copy(tlsData[tlsDataLen:], tlsData2) tlsDataLen += len(tlsData2) ticketLen := rand.Intn(164)*2 + 64 tlsData[tlsDataLen-1] = uint8(ticketLen & 0xff) tlsData[tlsDataLen-2] = uint8(ticketLen >> 8) //ticketLen := 208 rand.Read(tlsData[tlsDataLen : tlsDataLen+ticketLen]) tlsDataLen += ticketLen copy(tlsData[tlsDataLen:], tlsData3) tlsDataLen += len(tlsData3) length := 11 + 32 + 1 + 32 + len(tlsData0) + 2 + tlsDataLen encodedData := make([]byte, length) pdata := length - tlsDataLen l := tlsDataLen copy(encodedData[pdata:], tlsData[:tlsDataLen]) encodedData[pdata-1] = uint8(tlsDataLen) encodedData[pdata-2] = uint8(tlsDataLen >> 8) pdata -= 2 l += 2 copy(encodedData[pdata-len(tlsData0):], tlsData0) pdata -= len(tlsData0) l += len(tlsData0) copy(encodedData[pdata-32:], t.localClientID[:]) pdata -= 32 l += 32 encodedData[pdata-1] = 0x20 pdata-- l++ copy(encodedData[pdata-32:], t.packAuthData()) pdata -= 32 l += 32 encodedData[pdata-1] = 0x3 encodedData[pdata-2] = 0x3 // tls version pdata -= 2 l += 2 encodedData[pdata-1] = uint8(l) encodedData[pdata-2] = uint8(l >> 8) encodedData[pdata-3] = 0 encodedData[pdata-4] = 1 pdata -= 4 l += 4 encodedData[pdata-1] = uint8(l) encodedData[pdata-2] = uint8(l >> 8) pdata -= 2 l += 2 encodedData[pdata-1] = 0x1 encodedData[pdata-2] = 0x3 // tls version pdata -= 2 l += 2 encodedData[pdata-1] = 0x16 // tls handshake pdata-- l++ packData(&t.sendSaver, b) t.handshakeStatus = 1 return encodedData, nil default: return nil, fmt.Errorf("unexpected handshake status: %d", t.handshakeStatus) } } func (t *tls12Ticket) hmacSHA1(data []byte) []byte { key := make([]byte, len(t.Key)+32) copy(key, t.Key) copy(key[len(t.Key):], t.localClientID[:]) sha1Data := tools.HmacSHA1(key, data) return sha1Data[:tools.HmacSHA1Len] } func (t *tls12Ticket) sni(u string) []byte { bURL := []byte(u) length := len(bURL) ret := make([]byte, length+9) copy(ret[9:9+length], bURL) binary.BigEndian.PutUint16(ret[7:], uint16(length&0xFFFF)) length += 3 binary.BigEndian.PutUint16(ret[4:], uint16(length&0xFFFF)) length += 2 binary.BigEndian.PutUint16(ret[2:], uint16(length&0xFFFF)) return ret } func (t *tls12Ticket) getHost() string { host := t.Host if len(t.Param) > 0 { hosts := strings.Split(t.Param, ",") if len(hosts) > 0 { host = hosts[rand.Intn(len(hosts))] host = strings.TrimSpace(host) } } if len(host) > 0 && host[len(host)-1] >= byte('0') && host[len(host)-1] <= byte('9') && len(t.Param) == 0 { host = "" } return host } func (t *tls12Ticket) packAuthData() (ret []byte) { retSize := 32 ret = make([]byte, retSize) now := time.Now().Unix() binary.BigEndian.PutUint32(ret[:4], uint32(now)) rand.Read(ret[4 : 4+18]) hash := t.hmacSHA1(ret[:retSize-tools.HmacSHA1Len]) copy(ret[retSize-tools.HmacSHA1Len:], hash) return } func packData(buffer *bytes.Buffer, suffix []byte) { d := []byte{0x17, 0x3, 0x3, 0, 0} binary.BigEndian.PutUint16(d[3:5], uint16(len(suffix)&0xFFFF)) buffer.Write(d) buffer.Write(suffix) return }