mirror of
https://github.com/v2fly/v2ray-core.git
synced 2024-11-04 17:27:23 -05:00
317 lines
8.0 KiB
Go
317 lines
8.0 KiB
Go
package shadowsocks
|
|
|
|
import (
|
|
"bytes"
|
|
"crypto/aes"
|
|
"crypto/cipher"
|
|
"crypto/md5"
|
|
"crypto/sha1"
|
|
"io"
|
|
|
|
"golang.org/x/crypto/chacha20poly1305"
|
|
"golang.org/x/crypto/hkdf"
|
|
|
|
"v2ray.com/core/common"
|
|
"v2ray.com/core/common/buf"
|
|
"v2ray.com/core/common/crypto"
|
|
"v2ray.com/core/common/protocol"
|
|
)
|
|
|
|
// MemoryAccount is an account type converted from Account.
|
|
type MemoryAccount struct {
|
|
Cipher Cipher
|
|
Key []byte
|
|
OneTimeAuth Account_OneTimeAuth
|
|
}
|
|
|
|
// Equals implements protocol.Account.Equals().
|
|
func (a *MemoryAccount) Equals(another protocol.Account) bool {
|
|
if account, ok := another.(*MemoryAccount); ok {
|
|
return bytes.Equal(a.Key, account.Key)
|
|
}
|
|
return false
|
|
}
|
|
|
|
func createAesGcm(key []byte) cipher.AEAD {
|
|
block, err := aes.NewCipher(key)
|
|
common.Must(err)
|
|
gcm, err := cipher.NewGCM(block)
|
|
common.Must(err)
|
|
return gcm
|
|
}
|
|
|
|
func createChacha20Poly1305(key []byte) cipher.AEAD {
|
|
chacha20, err := chacha20poly1305.New(key)
|
|
common.Must(err)
|
|
return chacha20
|
|
}
|
|
|
|
func (a *Account) getCipher() (Cipher, error) {
|
|
switch a.CipherType {
|
|
case CipherType_AES_128_CFB:
|
|
return &AesCfb{KeyBytes: 16}, nil
|
|
case CipherType_AES_256_CFB:
|
|
return &AesCfb{KeyBytes: 32}, nil
|
|
case CipherType_CHACHA20:
|
|
return &ChaCha20{IVBytes: 8}, nil
|
|
case CipherType_CHACHA20_IETF:
|
|
return &ChaCha20{IVBytes: 12}, nil
|
|
case CipherType_AES_128_GCM:
|
|
return &AEADCipher{
|
|
KeyBytes: 16,
|
|
IVBytes: 16,
|
|
AEADAuthCreator: createAesGcm,
|
|
}, nil
|
|
case CipherType_AES_256_GCM:
|
|
return &AEADCipher{
|
|
KeyBytes: 32,
|
|
IVBytes: 32,
|
|
AEADAuthCreator: createAesGcm,
|
|
}, nil
|
|
case CipherType_CHACHA20_POLY1305:
|
|
return &AEADCipher{
|
|
KeyBytes: 32,
|
|
IVBytes: 32,
|
|
AEADAuthCreator: createChacha20Poly1305,
|
|
}, nil
|
|
case CipherType_NONE:
|
|
return NoneCipher{}, nil
|
|
default:
|
|
return nil, newError("Unsupported cipher.")
|
|
}
|
|
}
|
|
|
|
// AsAccount implements protocol.AsAccount.
|
|
func (a *Account) AsAccount() (protocol.Account, error) {
|
|
cipher, err := a.getCipher()
|
|
if err != nil {
|
|
return nil, newError("failed to get cipher").Base(err)
|
|
}
|
|
return &MemoryAccount{
|
|
Cipher: cipher,
|
|
Key: passwordToCipherKey([]byte(a.Password), cipher.KeySize()),
|
|
OneTimeAuth: a.Ota,
|
|
}, nil
|
|
}
|
|
|
|
// Cipher is an interface for all Shadowsocks ciphers.
|
|
type Cipher interface {
|
|
KeySize() int
|
|
IVSize() int
|
|
NewEncryptionWriter(key []byte, iv []byte, writer io.Writer) (buf.Writer, error)
|
|
NewDecryptionReader(key []byte, iv []byte, reader io.Reader) (buf.Reader, error)
|
|
IsAEAD() bool
|
|
EncodePacket(key []byte, b *buf.Buffer) error
|
|
DecodePacket(key []byte, b *buf.Buffer) error
|
|
}
|
|
|
|
// AesCfb represents all AES-CFB ciphers.
|
|
type AesCfb struct {
|
|
KeyBytes int
|
|
}
|
|
|
|
func (*AesCfb) IsAEAD() bool {
|
|
return false
|
|
}
|
|
|
|
func (v *AesCfb) KeySize() int {
|
|
return v.KeyBytes
|
|
}
|
|
|
|
func (v *AesCfb) IVSize() int {
|
|
return 16
|
|
}
|
|
|
|
func (v *AesCfb) NewEncryptionWriter(key []byte, iv []byte, writer io.Writer) (buf.Writer, error) {
|
|
stream := crypto.NewAesEncryptionStream(key, iv)
|
|
return buf.NewWriter(crypto.NewCryptionWriter(stream, writer)), nil
|
|
}
|
|
|
|
func (v *AesCfb) NewDecryptionReader(key []byte, iv []byte, reader io.Reader) (buf.Reader, error) {
|
|
stream := crypto.NewAesDecryptionStream(key, iv)
|
|
return buf.NewReader(crypto.NewCryptionReader(stream, reader)), nil
|
|
}
|
|
|
|
func (v *AesCfb) EncodePacket(key []byte, b *buf.Buffer) error {
|
|
iv := b.BytesTo(v.IVSize())
|
|
stream := crypto.NewAesEncryptionStream(key, iv)
|
|
stream.XORKeyStream(b.BytesFrom(v.IVSize()), b.BytesFrom(v.IVSize()))
|
|
return nil
|
|
}
|
|
|
|
func (v *AesCfb) DecodePacket(key []byte, b *buf.Buffer) error {
|
|
if b.Len() <= v.IVSize() {
|
|
return newError("insufficient data: ", b.Len())
|
|
}
|
|
iv := b.BytesTo(v.IVSize())
|
|
stream := crypto.NewAesDecryptionStream(key, iv)
|
|
stream.XORKeyStream(b.BytesFrom(v.IVSize()), b.BytesFrom(v.IVSize()))
|
|
b.SliceFrom(v.IVSize())
|
|
return nil
|
|
}
|
|
|
|
type AEADCipher struct {
|
|
KeyBytes int
|
|
IVBytes int
|
|
AEADAuthCreator func(key []byte) cipher.AEAD
|
|
}
|
|
|
|
func (*AEADCipher) IsAEAD() bool {
|
|
return true
|
|
}
|
|
|
|
func (c *AEADCipher) KeySize() int {
|
|
return c.KeyBytes
|
|
}
|
|
|
|
func (c *AEADCipher) IVSize() int {
|
|
return c.IVBytes
|
|
}
|
|
|
|
func (c *AEADCipher) createAuthenticator(key []byte, iv []byte) *crypto.AEADAuthenticator {
|
|
nonce := crypto.NewIncreasingAEADNonceGenerator()
|
|
subkey := make([]byte, c.KeyBytes)
|
|
hkdfSHA1(key, iv, subkey)
|
|
return &crypto.AEADAuthenticator{
|
|
AEAD: c.AEADAuthCreator(subkey),
|
|
NonceGenerator: nonce,
|
|
}
|
|
}
|
|
|
|
func (c *AEADCipher) NewEncryptionWriter(key []byte, iv []byte, writer io.Writer) (buf.Writer, error) {
|
|
auth := c.createAuthenticator(key, iv)
|
|
return crypto.NewAuthenticationWriter(auth, &crypto.AEADChunkSizeParser{
|
|
Auth: auth,
|
|
}, writer, protocol.TransferTypeStream), nil
|
|
}
|
|
|
|
func (c *AEADCipher) NewDecryptionReader(key []byte, iv []byte, reader io.Reader) (buf.Reader, error) {
|
|
auth := c.createAuthenticator(key, iv)
|
|
return crypto.NewAuthenticationReader(auth, &crypto.AEADChunkSizeParser{
|
|
Auth: auth,
|
|
}, reader, protocol.TransferTypeStream), nil
|
|
}
|
|
|
|
func (c *AEADCipher) EncodePacket(key []byte, b *buf.Buffer) error {
|
|
ivLen := c.IVSize()
|
|
payloadLen := b.Len()
|
|
auth := c.createAuthenticator(key, b.BytesTo(ivLen))
|
|
return b.Reset(func(bb []byte) (int, error) {
|
|
bbb, err := auth.Seal(bb[:ivLen], bb[ivLen:payloadLen])
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
return len(bbb), nil
|
|
})
|
|
}
|
|
|
|
func (c *AEADCipher) DecodePacket(key []byte, b *buf.Buffer) error {
|
|
if b.Len() <= c.IVSize() {
|
|
return newError("insufficient data: ", b.Len())
|
|
}
|
|
ivLen := c.IVSize()
|
|
payloadLen := b.Len()
|
|
auth := c.createAuthenticator(key, b.BytesTo(ivLen))
|
|
if err := b.Reset(func(bb []byte) (int, error) {
|
|
bbb, err := auth.Open(bb[:ivLen], bb[ivLen:payloadLen])
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
return len(bbb), nil
|
|
}); err != nil {
|
|
return err
|
|
}
|
|
b.SliceFrom(ivLen)
|
|
return nil
|
|
}
|
|
|
|
type ChaCha20 struct {
|
|
IVBytes int
|
|
}
|
|
|
|
func (*ChaCha20) IsAEAD() bool {
|
|
return false
|
|
}
|
|
|
|
func (v *ChaCha20) KeySize() int {
|
|
return 32
|
|
}
|
|
|
|
func (v *ChaCha20) IVSize() int {
|
|
return v.IVBytes
|
|
}
|
|
|
|
func (v *ChaCha20) NewEncryptionWriter(key []byte, iv []byte, writer io.Writer) (buf.Writer, error) {
|
|
stream := crypto.NewChaCha20Stream(key, iv)
|
|
return buf.NewWriter(crypto.NewCryptionWriter(stream, writer)), nil
|
|
}
|
|
|
|
func (v *ChaCha20) NewDecryptionReader(key []byte, iv []byte, reader io.Reader) (buf.Reader, error) {
|
|
stream := crypto.NewChaCha20Stream(key, iv)
|
|
return buf.NewReader(crypto.NewCryptionReader(stream, reader)), nil
|
|
}
|
|
|
|
func (v *ChaCha20) EncodePacket(key []byte, b *buf.Buffer) error {
|
|
iv := b.BytesTo(v.IVSize())
|
|
stream := crypto.NewChaCha20Stream(key, iv)
|
|
stream.XORKeyStream(b.BytesFrom(v.IVSize()), b.BytesFrom(v.IVSize()))
|
|
return nil
|
|
}
|
|
|
|
func (v *ChaCha20) DecodePacket(key []byte, b *buf.Buffer) error {
|
|
if b.Len() <= v.IVSize() {
|
|
return newError("insufficient data: ", b.Len())
|
|
}
|
|
iv := b.BytesTo(v.IVSize())
|
|
stream := crypto.NewChaCha20Stream(key, iv)
|
|
stream.XORKeyStream(b.BytesFrom(v.IVSize()), b.BytesFrom(v.IVSize()))
|
|
b.SliceFrom(v.IVSize())
|
|
return nil
|
|
}
|
|
|
|
type NoneCipher struct{}
|
|
|
|
func (NoneCipher) KeySize() int { return 0 }
|
|
func (NoneCipher) IVSize() int { return 0 }
|
|
func (NoneCipher) IsAEAD() bool {
|
|
return true // to avoid OTA
|
|
}
|
|
|
|
func (NoneCipher) NewDecryptionReader(key []byte, iv []byte, reader io.Reader) (buf.Reader, error) {
|
|
return buf.NewReader(reader), nil
|
|
}
|
|
|
|
func (NoneCipher) NewEncryptionWriter(key []byte, iv []byte, writer io.Writer) (buf.Writer, error) {
|
|
return buf.NewWriter(writer), nil
|
|
}
|
|
|
|
func (NoneCipher) EncodePacket(key []byte, b *buf.Buffer) error {
|
|
return nil
|
|
}
|
|
|
|
func (NoneCipher) DecodePacket(key []byte, b *buf.Buffer) error {
|
|
return nil
|
|
}
|
|
|
|
func passwordToCipherKey(password []byte, keySize int) []byte {
|
|
key := make([]byte, 0, keySize)
|
|
|
|
md5Sum := md5.Sum(password)
|
|
key = append(key, md5Sum[:]...)
|
|
|
|
for len(key) < keySize {
|
|
md5Hash := md5.New()
|
|
common.Must2(md5Hash.Write(md5Sum[:]))
|
|
common.Must2(md5Hash.Write(password))
|
|
md5Hash.Sum(md5Sum[:0])
|
|
|
|
key = append(key, md5Sum[:]...)
|
|
}
|
|
return key
|
|
}
|
|
|
|
func hkdfSHA1(secret, salt, outkey []byte) {
|
|
r := hkdf.New(sha1.New, secret, salt, []byte("ss-subkey"))
|
|
common.Must2(io.ReadFull(r, outkey))
|
|
}
|