mirror of
https://github.com/v2fly/v2ray-core.git
synced 2024-08-21 20:04:51 -04:00
270 lines
7.7 KiB
Go
270 lines
7.7 KiB
Go
package quic
|
|
|
|
import (
|
|
"crypto"
|
|
"crypto/aes"
|
|
"crypto/tls"
|
|
"encoding/binary"
|
|
"io"
|
|
|
|
"github.com/quic-go/quic-go/quicvarint"
|
|
"golang.org/x/crypto/hkdf"
|
|
|
|
"github.com/v2fly/v2ray-core/v5/common"
|
|
"github.com/v2fly/v2ray-core/v5/common/buf"
|
|
"github.com/v2fly/v2ray-core/v5/common/bytespool"
|
|
"github.com/v2fly/v2ray-core/v5/common/errors"
|
|
ptls "github.com/v2fly/v2ray-core/v5/common/protocol/tls"
|
|
)
|
|
|
|
type SniffHeader struct {
|
|
domain string
|
|
}
|
|
|
|
func (s SniffHeader) Protocol() string {
|
|
return "quic"
|
|
}
|
|
|
|
func (s SniffHeader) Domain() string {
|
|
return s.domain
|
|
}
|
|
|
|
const (
|
|
versionDraft29 uint32 = 0xff00001d
|
|
version1 uint32 = 0x1
|
|
)
|
|
|
|
var (
|
|
quicSaltOld = []byte{0xaf, 0xbf, 0xec, 0x28, 0x99, 0x93, 0xd2, 0x4c, 0x9e, 0x97, 0x86, 0xf1, 0x9c, 0x61, 0x11, 0xe0, 0x43, 0x90, 0xa8, 0x99}
|
|
quicSalt = []byte{0x38, 0x76, 0x2c, 0xf7, 0xf5, 0x59, 0x34, 0xb3, 0x4d, 0x17, 0x9a, 0xe6, 0xa4, 0xc8, 0x0c, 0xad, 0xcc, 0xbb, 0x7f, 0x0a}
|
|
initialSuite = &CipherSuiteTLS13{
|
|
ID: tls.TLS_AES_128_GCM_SHA256,
|
|
KeyLen: 16,
|
|
AEAD: AEADAESGCMTLS13,
|
|
Hash: crypto.SHA256,
|
|
}
|
|
errNotQuic = errors.New("not quic")
|
|
errNotQuicInitial = errors.New("not initial packet")
|
|
)
|
|
|
|
func SniffQUIC(b []byte) (*SniffHeader, error) {
|
|
buffer := buf.FromBytes(b)
|
|
typeByte, err := buffer.ReadByte()
|
|
if err != nil {
|
|
return nil, errNotQuic
|
|
}
|
|
isLongHeader := typeByte&0x80 > 0
|
|
if !isLongHeader || typeByte&0x40 == 0 {
|
|
return nil, errNotQuicInitial
|
|
}
|
|
|
|
vb, err := buffer.ReadBytes(4)
|
|
if err != nil {
|
|
return nil, errNotQuic
|
|
}
|
|
|
|
versionNumber := binary.BigEndian.Uint32(vb)
|
|
|
|
if versionNumber != 0 && typeByte&0x40 == 0 {
|
|
return nil, errNotQuic
|
|
} else if versionNumber != versionDraft29 && versionNumber != version1 {
|
|
return nil, errNotQuic
|
|
}
|
|
|
|
if (typeByte&0x30)>>4 != 0x0 {
|
|
return nil, errNotQuicInitial
|
|
}
|
|
|
|
var destConnID []byte
|
|
if l, err := buffer.ReadByte(); err != nil {
|
|
return nil, errNotQuic
|
|
} else if destConnID, err = buffer.ReadBytes(int32(l)); err != nil {
|
|
return nil, errNotQuic
|
|
}
|
|
|
|
if l, err := buffer.ReadByte(); err != nil {
|
|
return nil, errNotQuic
|
|
} else if common.Error2(buffer.ReadBytes(int32(l))) != nil {
|
|
return nil, errNotQuic
|
|
}
|
|
|
|
tokenLen, err := quicvarint.Read(buffer)
|
|
if err != nil || tokenLen > uint64(len(b)) {
|
|
return nil, errNotQuic
|
|
}
|
|
|
|
if _, err = buffer.ReadBytes(int32(tokenLen)); err != nil {
|
|
return nil, errNotQuic
|
|
}
|
|
|
|
packetLen, err := quicvarint.Read(buffer)
|
|
if err != nil {
|
|
return nil, errNotQuic
|
|
}
|
|
|
|
hdrLen := len(b) - int(buffer.Len())
|
|
|
|
origPNBytes := make([]byte, 4)
|
|
copy(origPNBytes, b[hdrLen:hdrLen+4])
|
|
|
|
var salt []byte
|
|
if versionNumber == version1 {
|
|
salt = quicSalt
|
|
} else {
|
|
salt = quicSaltOld
|
|
}
|
|
initialSecret := hkdf.Extract(crypto.SHA256.New, destConnID, salt)
|
|
secret := hkdfExpandLabel(crypto.SHA256, initialSecret, []byte{}, "client in", crypto.SHA256.Size())
|
|
hpKey := hkdfExpandLabel(initialSuite.Hash, secret, []byte{}, "quic hp", initialSuite.KeyLen)
|
|
block, err := aes.NewCipher(hpKey)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
cache := buf.New()
|
|
defer cache.Release()
|
|
|
|
mask := cache.Extend(int32(block.BlockSize()))
|
|
block.Encrypt(mask, b[hdrLen+4:hdrLen+4+16])
|
|
b[0] ^= mask[0] & 0xf
|
|
for i := range b[hdrLen : hdrLen+4] {
|
|
b[hdrLen+i] ^= mask[i+1]
|
|
}
|
|
packetNumberLength := b[0]&0x3 + 1
|
|
if packetNumberLength != 1 {
|
|
return nil, errNotQuicInitial
|
|
}
|
|
var packetNumber uint32
|
|
{
|
|
n, err := buffer.ReadByte()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
packetNumber = uint32(n)
|
|
}
|
|
|
|
if packetNumber != 0 && packetNumber != 1 {
|
|
return nil, errNotQuicInitial
|
|
}
|
|
|
|
extHdrLen := hdrLen + int(packetNumberLength)
|
|
copy(b[extHdrLen:hdrLen+4], origPNBytes[packetNumberLength:])
|
|
data := b[extHdrLen : int(packetLen)+hdrLen]
|
|
|
|
key := hkdfExpandLabel(crypto.SHA256, secret, []byte{}, "quic key", 16)
|
|
iv := hkdfExpandLabel(crypto.SHA256, secret, []byte{}, "quic iv", 12)
|
|
cipher := AEADAESGCMTLS13(key, iv)
|
|
nonce := cache.Extend(int32(cipher.NonceSize()))
|
|
binary.BigEndian.PutUint64(nonce[len(nonce)-8:], uint64(packetNumber))
|
|
decrypted, err := cipher.Open(b[extHdrLen:extHdrLen], nonce, data, b[:extHdrLen])
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
buffer = buf.FromBytes(decrypted)
|
|
|
|
cryptoLen := uint(0)
|
|
cryptoData := bytespool.Alloc(buffer.Len())
|
|
defer bytespool.Free(cryptoData)
|
|
for i := 0; !buffer.IsEmpty(); i++ {
|
|
frameType := byte(0x0) // Default to PADDING frame
|
|
for frameType == 0x0 && !buffer.IsEmpty() {
|
|
frameType, _ = buffer.ReadByte()
|
|
}
|
|
switch frameType {
|
|
case 0x00: // PADDING frame
|
|
case 0x01: // PING frame
|
|
case 0x02, 0x03: // ACK frame
|
|
if _, err = quicvarint.Read(buffer); err != nil { // Field: Largest Acknowledged
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
if _, err = quicvarint.Read(buffer); err != nil { // Field: ACK Delay
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
ackRangeCount, err := quicvarint.Read(buffer) // Field: ACK Range Count
|
|
if err != nil {
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
if _, err = quicvarint.Read(buffer); err != nil { // Field: First ACK Range
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
for i := 0; i < int(ackRangeCount); i++ { // Field: ACK Range
|
|
if _, err = quicvarint.Read(buffer); err != nil { // Field: ACK Range -> Gap
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
if _, err = quicvarint.Read(buffer); err != nil { // Field: ACK Range -> ACK Range Length
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
}
|
|
if frameType == 0x03 {
|
|
if _, err = quicvarint.Read(buffer); err != nil { // Field: ECN Counts -> ECT0 Count
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
if _, err = quicvarint.Read(buffer); err != nil { // Field: ECN Counts -> ECT1 Count
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
if _, err = quicvarint.Read(buffer); err != nil { //nolint:misspell // Field: ECN Counts -> ECT-CE Count
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
}
|
|
case 0x06: // CRYPTO frame, we will use this frame
|
|
offset, err := quicvarint.Read(buffer) // Field: Offset
|
|
if err != nil {
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
length, err := quicvarint.Read(buffer) // Field: Length
|
|
if err != nil || length > uint64(buffer.Len()) {
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
if cryptoLen < uint(offset+length) {
|
|
cryptoLen = uint(offset + length)
|
|
}
|
|
if _, err := buffer.Read(cryptoData[offset : offset+length]); err != nil { // Field: Crypto Data
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
case 0x1c: // CONNECTION_CLOSE frame, only 0x1c is permitted in initial packet
|
|
if _, err = quicvarint.Read(buffer); err != nil { // Field: Error Code
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
if _, err = quicvarint.Read(buffer); err != nil { // Field: Frame Type
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
length, err := quicvarint.Read(buffer) // Field: Reason Phrase Length
|
|
if err != nil {
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
if _, err := buffer.ReadBytes(int32(length)); err != nil { // Field: Reason Phrase
|
|
return nil, io.ErrUnexpectedEOF
|
|
}
|
|
default:
|
|
// Only above frame types are permitted in initial packet.
|
|
// See https://www.rfc-editor.org/rfc/rfc9000.html#section-17.2.2-8
|
|
return nil, errNotQuicInitial
|
|
}
|
|
}
|
|
|
|
tlsHdr := &ptls.SniffHeader{}
|
|
err = ptls.ReadClientHello(cryptoData[:cryptoLen], tlsHdr)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &SniffHeader{domain: tlsHdr.Domain()}, nil
|
|
}
|
|
|
|
func hkdfExpandLabel(hash crypto.Hash, secret, context []byte, label string, length int) []byte {
|
|
b := make([]byte, 3, 3+6+len(label)+1+len(context))
|
|
binary.BigEndian.PutUint16(b, uint16(length))
|
|
b[2] = uint8(6 + len(label))
|
|
b = append(b, []byte("tls13 ")...)
|
|
b = append(b, []byte(label)...)
|
|
b = b[:3+6+len(label)+1]
|
|
b[3+6+len(label)] = uint8(len(context))
|
|
b = append(b, context...)
|
|
|
|
out := make([]byte, length)
|
|
n, err := hkdf.Expand(hash.New, secret, b).Read(out)
|
|
if err != nil || n != length {
|
|
panic("quic: HKDF-Expand-Label invocation failed unexpectedly")
|
|
}
|
|
return out
|
|
}
|