mirror of
https://github.com/XTLS/Xray-core.git
synced 2024-11-30 09:06:03 +03:00
120 lines
2.7 KiB
Go
120 lines
2.7 KiB
Go
package encoding
|
|
|
|
import (
|
|
"crypto/md5"
|
|
"encoding/binary"
|
|
"hash/fnv"
|
|
|
|
"github.com/xtls/xray-core/common"
|
|
|
|
"golang.org/x/crypto/sha3"
|
|
)
|
|
|
|
// Authenticate authenticates a byte array using Fnv hash.
|
|
func Authenticate(b []byte) uint32 {
|
|
fnv1hash := fnv.New32a()
|
|
common.Must2(fnv1hash.Write(b))
|
|
return fnv1hash.Sum32()
|
|
}
|
|
|
|
type NoOpAuthenticator struct{}
|
|
|
|
func (NoOpAuthenticator) NonceSize() int {
|
|
return 0
|
|
}
|
|
|
|
func (NoOpAuthenticator) Overhead() int {
|
|
return 0
|
|
}
|
|
|
|
// Seal implements AEAD.Seal().
|
|
func (NoOpAuthenticator) Seal(dst, nonce, plaintext, additionalData []byte) []byte {
|
|
return append(dst[:0], plaintext...)
|
|
}
|
|
|
|
// Open implements AEAD.Open().
|
|
func (NoOpAuthenticator) Open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error) {
|
|
return append(dst[:0], ciphertext...), nil
|
|
}
|
|
|
|
// FnvAuthenticator is an AEAD based on Fnv hash.
|
|
type FnvAuthenticator struct {
|
|
}
|
|
|
|
// NonceSize implements AEAD.NonceSize().
|
|
func (*FnvAuthenticator) NonceSize() int {
|
|
return 0
|
|
}
|
|
|
|
// Overhead impelements AEAD.Overhead().
|
|
func (*FnvAuthenticator) Overhead() int {
|
|
return 4
|
|
}
|
|
|
|
// Seal implements AEAD.Seal().
|
|
func (*FnvAuthenticator) Seal(dst, nonce, plaintext, additionalData []byte) []byte {
|
|
dst = append(dst, 0, 0, 0, 0)
|
|
binary.BigEndian.PutUint32(dst, Authenticate(plaintext))
|
|
return append(dst, plaintext...)
|
|
}
|
|
|
|
// Open implements AEAD.Open().
|
|
func (*FnvAuthenticator) Open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error) {
|
|
if binary.BigEndian.Uint32(ciphertext[:4]) != Authenticate(ciphertext[4:]) {
|
|
return dst, newError("invalid authentication")
|
|
}
|
|
return append(dst, ciphertext[4:]...), nil
|
|
}
|
|
|
|
// GenerateChacha20Poly1305Key generates a 32-byte key from a given 16-byte array.
|
|
func GenerateChacha20Poly1305Key(b []byte) []byte {
|
|
key := make([]byte, 32)
|
|
t := md5.Sum(b)
|
|
copy(key, t[:])
|
|
t = md5.Sum(key[:16])
|
|
copy(key[16:], t[:])
|
|
return key
|
|
}
|
|
|
|
type ShakeSizeParser struct {
|
|
shake sha3.ShakeHash
|
|
buffer [2]byte
|
|
}
|
|
|
|
func NewShakeSizeParser(nonce []byte) *ShakeSizeParser {
|
|
shake := sha3.NewShake128()
|
|
common.Must2(shake.Write(nonce))
|
|
return &ShakeSizeParser{
|
|
shake: shake,
|
|
}
|
|
}
|
|
|
|
func (*ShakeSizeParser) SizeBytes() int32 {
|
|
return 2
|
|
}
|
|
|
|
func (s *ShakeSizeParser) next() uint16 {
|
|
common.Must2(s.shake.Read(s.buffer[:]))
|
|
return binary.BigEndian.Uint16(s.buffer[:])
|
|
}
|
|
|
|
func (s *ShakeSizeParser) Decode(b []byte) (uint16, error) {
|
|
mask := s.next()
|
|
size := binary.BigEndian.Uint16(b)
|
|
return mask ^ size, nil
|
|
}
|
|
|
|
func (s *ShakeSizeParser) Encode(size uint16, b []byte) []byte {
|
|
mask := s.next()
|
|
binary.BigEndian.PutUint16(b, mask^size)
|
|
return b[:2]
|
|
}
|
|
|
|
func (s *ShakeSizeParser) NextPaddingLen() uint16 {
|
|
return s.next() % 64
|
|
}
|
|
|
|
func (s *ShakeSizeParser) MaxPaddingLen() uint16 {
|
|
return 64
|
|
}
|