mirror of
https://github.com/v2fly/v2ray-core.git
synced 2024-09-18 09:57:04 -04:00
105 lines
2.6 KiB
Go
105 lines
2.6 KiB
Go
package handshake
|
|
|
|
import (
|
|
"crypto/cipher"
|
|
"encoding/binary"
|
|
|
|
"v2ray.com/core/external/github.com/lucas-clemente/quic-go/internal/protocol"
|
|
)
|
|
|
|
type sealer struct {
|
|
aead cipher.AEAD
|
|
hpEncrypter cipher.Block
|
|
|
|
// use a single slice to avoid allocations
|
|
nonceBuf []byte
|
|
hpMask []byte
|
|
|
|
// short headers protect 5 bits in the first byte, long headers only 4
|
|
is1RTT bool
|
|
}
|
|
|
|
var _ Sealer = &sealer{}
|
|
|
|
func newSealer(aead cipher.AEAD, hpEncrypter cipher.Block, is1RTT bool) Sealer {
|
|
return &sealer{
|
|
aead: aead,
|
|
nonceBuf: make([]byte, aead.NonceSize()),
|
|
is1RTT: is1RTT,
|
|
hpEncrypter: hpEncrypter,
|
|
hpMask: make([]byte, hpEncrypter.BlockSize()),
|
|
}
|
|
}
|
|
|
|
func (s *sealer) Seal(dst, src []byte, pn protocol.PacketNumber, ad []byte) []byte {
|
|
binary.BigEndian.PutUint64(s.nonceBuf[len(s.nonceBuf)-8:], uint64(pn))
|
|
// The AEAD we're using here will be the qtls.aeadAESGCM13.
|
|
// It uses the nonce provided here and XOR it with the IV.
|
|
return s.aead.Seal(dst, s.nonceBuf, src, ad)
|
|
}
|
|
|
|
func (s *sealer) EncryptHeader(sample []byte, firstByte *byte, pnBytes []byte) {
|
|
if len(sample) != s.hpEncrypter.BlockSize() {
|
|
panic("invalid sample size")
|
|
}
|
|
s.hpEncrypter.Encrypt(s.hpMask, sample)
|
|
if s.is1RTT {
|
|
*firstByte ^= s.hpMask[0] & 0x1f
|
|
} else {
|
|
*firstByte ^= s.hpMask[0] & 0xf
|
|
}
|
|
for i := range pnBytes {
|
|
pnBytes[i] ^= s.hpMask[i+1]
|
|
}
|
|
}
|
|
|
|
func (s *sealer) Overhead() int {
|
|
return s.aead.Overhead()
|
|
}
|
|
|
|
type opener struct {
|
|
aead cipher.AEAD
|
|
pnDecrypter cipher.Block
|
|
|
|
// use a single slice to avoid allocations
|
|
nonceBuf []byte
|
|
hpMask []byte
|
|
|
|
// short headers protect 5 bits in the first byte, long headers only 4
|
|
is1RTT bool
|
|
}
|
|
|
|
var _ Opener = &opener{}
|
|
|
|
func newOpener(aead cipher.AEAD, pnDecrypter cipher.Block, is1RTT bool) Opener {
|
|
return &opener{
|
|
aead: aead,
|
|
nonceBuf: make([]byte, aead.NonceSize()),
|
|
is1RTT: is1RTT,
|
|
pnDecrypter: pnDecrypter,
|
|
hpMask: make([]byte, pnDecrypter.BlockSize()),
|
|
}
|
|
}
|
|
|
|
func (o *opener) Open(dst, src []byte, pn protocol.PacketNumber, ad []byte) ([]byte, error) {
|
|
binary.BigEndian.PutUint64(o.nonceBuf[len(o.nonceBuf)-8:], uint64(pn))
|
|
// The AEAD we're using here will be the qtls.aeadAESGCM13.
|
|
// It uses the nonce provided here and XOR it with the IV.
|
|
return o.aead.Open(dst, o.nonceBuf, src, ad)
|
|
}
|
|
|
|
func (o *opener) DecryptHeader(sample []byte, firstByte *byte, pnBytes []byte) {
|
|
if len(sample) != o.pnDecrypter.BlockSize() {
|
|
panic("invalid sample size")
|
|
}
|
|
o.pnDecrypter.Encrypt(o.hpMask, sample)
|
|
if o.is1RTT {
|
|
*firstByte ^= o.hpMask[0] & 0x1f
|
|
} else {
|
|
*firstByte ^= o.hpMask[0] & 0xf
|
|
}
|
|
for i := range pnBytes {
|
|
pnBytes[i] ^= o.hpMask[i+1]
|
|
}
|
|
}
|