mirror of
https://github.com/v2fly/v2ray-core.git
synced 2024-06-10 09:50:43 +00:00
369 lines
11 KiB
Go
369 lines
11 KiB
Go
package encoding
|
|
|
|
import (
|
|
"crypto/aes"
|
|
"crypto/cipher"
|
|
"crypto/md5"
|
|
"hash/fnv"
|
|
"io"
|
|
"sync"
|
|
"time"
|
|
|
|
"golang.org/x/crypto/chacha20poly1305"
|
|
"v2ray.com/core/common"
|
|
"v2ray.com/core/common/bitmask"
|
|
"v2ray.com/core/common/buf"
|
|
"v2ray.com/core/common/crypto"
|
|
"v2ray.com/core/common/net"
|
|
"v2ray.com/core/common/protocol"
|
|
"v2ray.com/core/common/serial"
|
|
"v2ray.com/core/common/signal"
|
|
"v2ray.com/core/proxy/vmess"
|
|
)
|
|
|
|
type sessionId struct {
|
|
user [16]byte
|
|
key [16]byte
|
|
nonce [16]byte
|
|
}
|
|
|
|
type SessionHistory struct {
|
|
sync.RWMutex
|
|
cache map[sessionId]time.Time
|
|
task *signal.PeriodicTask
|
|
}
|
|
|
|
func NewSessionHistory() *SessionHistory {
|
|
h := &SessionHistory{
|
|
cache: make(map[sessionId]time.Time, 128),
|
|
}
|
|
h.task = &signal.PeriodicTask{
|
|
Interval: time.Second * 30,
|
|
Execute: func() error {
|
|
h.removeExpiredEntries()
|
|
return nil
|
|
},
|
|
}
|
|
common.Must(h.task.Start())
|
|
return h
|
|
}
|
|
|
|
// Close implements common.Closable.
|
|
func (h *SessionHistory) Close() error {
|
|
return h.task.Close()
|
|
}
|
|
|
|
func (h *SessionHistory) add(session sessionId) {
|
|
h.Lock()
|
|
defer h.Unlock()
|
|
|
|
h.cache[session] = time.Now().Add(time.Minute * 3)
|
|
}
|
|
|
|
func (h *SessionHistory) has(session sessionId) bool {
|
|
h.RLock()
|
|
defer h.RUnlock()
|
|
|
|
if expire, found := h.cache[session]; found {
|
|
return expire.After(time.Now())
|
|
}
|
|
return false
|
|
}
|
|
|
|
func (h *SessionHistory) removeExpiredEntries() {
|
|
now := time.Now()
|
|
|
|
h.Lock()
|
|
defer h.Unlock()
|
|
|
|
for session, expire := range h.cache {
|
|
if expire.Before(now) {
|
|
delete(h.cache, session)
|
|
}
|
|
}
|
|
}
|
|
|
|
type ServerSession struct {
|
|
userValidator protocol.UserValidator
|
|
sessionHistory *SessionHistory
|
|
requestBodyKey []byte
|
|
requestBodyIV []byte
|
|
responseBodyKey []byte
|
|
responseBodyIV []byte
|
|
responseHeader byte
|
|
responseWriter io.Writer
|
|
}
|
|
|
|
// NewServerSession creates a new ServerSession, using the given UserValidator.
|
|
// The ServerSession instance doesn't take ownership of the validator.
|
|
func NewServerSession(validator protocol.UserValidator, sessionHistory *SessionHistory) *ServerSession {
|
|
return &ServerSession{
|
|
userValidator: validator,
|
|
sessionHistory: sessionHistory,
|
|
}
|
|
}
|
|
|
|
func (s *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.RequestHeader, error) {
|
|
buffer := buf.New()
|
|
defer buffer.Release()
|
|
|
|
if err := buffer.AppendSupplier(buf.ReadFullFrom(reader, protocol.IDBytesLen)); err != nil {
|
|
return nil, newError("failed to read request header").Base(err)
|
|
}
|
|
|
|
user, timestamp, valid := s.userValidator.Get(buffer.Bytes())
|
|
if !valid {
|
|
return nil, newError("invalid user")
|
|
}
|
|
|
|
timestampHash := md5.New()
|
|
common.Must2(timestampHash.Write(hashTimestamp(timestamp)))
|
|
iv := timestampHash.Sum(nil)
|
|
account, err := user.GetTypedAccount()
|
|
if err != nil {
|
|
return nil, newError("failed to get user account").Base(err)
|
|
}
|
|
vmessAccount := account.(*vmess.InternalAccount)
|
|
|
|
aesStream := crypto.NewAesDecryptionStream(vmessAccount.ID.CmdKey(), iv)
|
|
decryptor := crypto.NewCryptionReader(aesStream, reader)
|
|
|
|
if err := buffer.Reset(buf.ReadFullFrom(decryptor, 41)); err != nil {
|
|
return nil, newError("failed to read request header").Base(err)
|
|
}
|
|
|
|
request := &protocol.RequestHeader{
|
|
User: user,
|
|
Version: buffer.Byte(0),
|
|
}
|
|
|
|
if request.Version != Version {
|
|
return nil, newError("invalid protocol version ", request.Version)
|
|
}
|
|
|
|
s.requestBodyIV = append([]byte(nil), buffer.BytesRange(1, 17)...) // 16 bytes
|
|
s.requestBodyKey = append([]byte(nil), buffer.BytesRange(17, 33)...) // 16 bytes
|
|
var sid sessionId
|
|
copy(sid.user[:], vmessAccount.ID.Bytes())
|
|
copy(sid.key[:], s.requestBodyKey)
|
|
copy(sid.nonce[:], s.requestBodyIV)
|
|
if s.sessionHistory.has(sid) {
|
|
return nil, newError("duplicated session id, possibly under replay attack")
|
|
}
|
|
s.sessionHistory.add(sid)
|
|
|
|
s.responseHeader = buffer.Byte(33) // 1 byte
|
|
request.Option = bitmask.Byte(buffer.Byte(34)) // 1 byte
|
|
padingLen := int(buffer.Byte(35) >> 4)
|
|
request.Security = protocol.NormSecurity(protocol.Security(buffer.Byte(35) & 0x0F))
|
|
// 1 bytes reserved
|
|
request.Command = protocol.RequestCommand(buffer.Byte(37))
|
|
|
|
if request.Command != protocol.RequestCommandMux {
|
|
request.Port = net.PortFromBytes(buffer.BytesRange(38, 40))
|
|
|
|
switch protocol.AddressType(buffer.Byte(40)) {
|
|
case protocol.AddressTypeIPv4:
|
|
if err := buffer.AppendSupplier(buf.ReadFullFrom(decryptor, 4)); err != nil {
|
|
return nil, newError("failed to read IPv4 address").Base(err)
|
|
}
|
|
request.Address = net.IPAddress(buffer.BytesFrom(-4))
|
|
case protocol.AddressTypeIPv6:
|
|
if err := buffer.AppendSupplier(buf.ReadFullFrom(decryptor, 16)); err != nil {
|
|
return nil, newError("failed to read IPv6 address").Base(err)
|
|
}
|
|
request.Address = net.IPAddress(buffer.BytesFrom(-16))
|
|
case protocol.AddressTypeDomain:
|
|
if err := buffer.AppendSupplier(buf.ReadFullFrom(decryptor, 1)); err != nil {
|
|
return nil, newError("failed to read domain address").Base(err)
|
|
}
|
|
domainLength := int(buffer.Byte(buffer.Len() - 1))
|
|
if domainLength == 0 {
|
|
return nil, newError("zero length domain").Base(err)
|
|
}
|
|
if err := buffer.AppendSupplier(buf.ReadFullFrom(decryptor, domainLength)); err != nil {
|
|
return nil, newError("failed to read domain address").Base(err)
|
|
}
|
|
request.Address = net.DomainAddress(string(buffer.BytesFrom(-domainLength)))
|
|
}
|
|
}
|
|
|
|
if padingLen > 0 {
|
|
if err := buffer.AppendSupplier(buf.ReadFullFrom(decryptor, padingLen)); err != nil {
|
|
return nil, newError("failed to read padding").Base(err)
|
|
}
|
|
}
|
|
|
|
if err := buffer.AppendSupplier(buf.ReadFullFrom(decryptor, 4)); err != nil {
|
|
return nil, newError("failed to read checksum").Base(err)
|
|
}
|
|
|
|
fnv1a := fnv.New32a()
|
|
common.Must2(fnv1a.Write(buffer.BytesTo(-4)))
|
|
actualHash := fnv1a.Sum32()
|
|
expectedHash := serial.BytesToUint32(buffer.BytesFrom(-4))
|
|
|
|
if actualHash != expectedHash {
|
|
return nil, newError("invalid auth")
|
|
}
|
|
|
|
if request.Address == nil {
|
|
return nil, newError("invalid remote address")
|
|
}
|
|
|
|
return request, nil
|
|
}
|
|
|
|
func (s *ServerSession) DecodeRequestBody(request *protocol.RequestHeader, reader io.Reader) buf.Reader {
|
|
var sizeParser crypto.ChunkSizeDecoder = crypto.PlainChunkSizeParser{}
|
|
if request.Option.Has(protocol.RequestOptionChunkMasking) {
|
|
sizeParser = NewShakeSizeParser(s.requestBodyIV)
|
|
}
|
|
if request.Security.Is(protocol.SecurityType_NONE) {
|
|
if request.Option.Has(protocol.RequestOptionChunkStream) {
|
|
if request.Command == protocol.RequestCommandTCP {
|
|
return crypto.NewChunkStreamReader(sizeParser, reader)
|
|
}
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: new(NoOpAuthenticator),
|
|
NonceGenerator: crypto.NoOpBytesGenerator{},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
return crypto.NewAuthenticationReader(auth, sizeParser, reader, protocol.TransferTypePacket)
|
|
}
|
|
|
|
return buf.NewReader(reader)
|
|
}
|
|
|
|
if request.Security.Is(protocol.SecurityType_LEGACY) {
|
|
aesStream := crypto.NewAesDecryptionStream(s.requestBodyKey, s.requestBodyIV)
|
|
cryptionReader := crypto.NewCryptionReader(aesStream, reader)
|
|
if request.Option.Has(protocol.RequestOptionChunkStream) {
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: new(FnvAuthenticator),
|
|
NonceGenerator: crypto.NoOpBytesGenerator{},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
return crypto.NewAuthenticationReader(auth, sizeParser, cryptionReader, request.Command.TransferType())
|
|
}
|
|
|
|
return buf.NewReader(cryptionReader)
|
|
}
|
|
|
|
if request.Security.Is(protocol.SecurityType_AES128_GCM) {
|
|
block, _ := aes.NewCipher(s.requestBodyKey)
|
|
aead, _ := cipher.NewGCM(block)
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: aead,
|
|
NonceGenerator: &ChunkNonceGenerator{
|
|
Nonce: append([]byte(nil), s.requestBodyIV...),
|
|
Size: aead.NonceSize(),
|
|
},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
return crypto.NewAuthenticationReader(auth, sizeParser, reader, request.Command.TransferType())
|
|
}
|
|
|
|
if request.Security.Is(protocol.SecurityType_CHACHA20_POLY1305) {
|
|
aead, _ := chacha20poly1305.New(GenerateChacha20Poly1305Key(s.requestBodyKey))
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: aead,
|
|
NonceGenerator: &ChunkNonceGenerator{
|
|
Nonce: append([]byte(nil), s.requestBodyIV...),
|
|
Size: aead.NonceSize(),
|
|
},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
return crypto.NewAuthenticationReader(auth, sizeParser, reader, request.Command.TransferType())
|
|
}
|
|
|
|
panic("Unknown security type.")
|
|
}
|
|
|
|
func (s *ServerSession) EncodeResponseHeader(header *protocol.ResponseHeader, writer io.Writer) {
|
|
responseBodyKey := md5.Sum(s.requestBodyKey)
|
|
responseBodyIV := md5.Sum(s.requestBodyIV)
|
|
s.responseBodyKey = responseBodyKey[:]
|
|
s.responseBodyIV = responseBodyIV[:]
|
|
|
|
aesStream := crypto.NewAesEncryptionStream(s.responseBodyKey, s.responseBodyIV)
|
|
encryptionWriter := crypto.NewCryptionWriter(aesStream, writer)
|
|
s.responseWriter = encryptionWriter
|
|
|
|
common.Must2(encryptionWriter.Write([]byte{s.responseHeader, byte(header.Option)}))
|
|
err := MarshalCommand(header.Command, encryptionWriter)
|
|
if err != nil {
|
|
common.Must2(encryptionWriter.Write([]byte{0x00, 0x00}))
|
|
}
|
|
}
|
|
|
|
func (s *ServerSession) EncodeResponseBody(request *protocol.RequestHeader, writer io.Writer) buf.Writer {
|
|
var sizeParser crypto.ChunkSizeEncoder = crypto.PlainChunkSizeParser{}
|
|
if request.Option.Has(protocol.RequestOptionChunkMasking) {
|
|
sizeParser = NewShakeSizeParser(s.responseBodyIV)
|
|
}
|
|
if request.Security.Is(protocol.SecurityType_NONE) {
|
|
if request.Option.Has(protocol.RequestOptionChunkStream) {
|
|
if request.Command == protocol.RequestCommandTCP {
|
|
return crypto.NewChunkStreamWriter(sizeParser, writer)
|
|
}
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: new(NoOpAuthenticator),
|
|
NonceGenerator: &crypto.NoOpBytesGenerator{},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
return crypto.NewAuthenticationWriter(auth, sizeParser, writer, protocol.TransferTypePacket)
|
|
}
|
|
|
|
return buf.NewWriter(writer)
|
|
}
|
|
|
|
if request.Security.Is(protocol.SecurityType_LEGACY) {
|
|
if request.Option.Has(protocol.RequestOptionChunkStream) {
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: new(FnvAuthenticator),
|
|
NonceGenerator: crypto.NoOpBytesGenerator{},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
return crypto.NewAuthenticationWriter(auth, sizeParser, s.responseWriter, request.Command.TransferType())
|
|
}
|
|
|
|
return buf.NewWriter(s.responseWriter)
|
|
}
|
|
|
|
if request.Security.Is(protocol.SecurityType_AES128_GCM) {
|
|
block, _ := aes.NewCipher(s.responseBodyKey)
|
|
aead, _ := cipher.NewGCM(block)
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: aead,
|
|
NonceGenerator: &ChunkNonceGenerator{
|
|
Nonce: append([]byte(nil), s.responseBodyIV...),
|
|
Size: aead.NonceSize(),
|
|
},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
return crypto.NewAuthenticationWriter(auth, sizeParser, writer, request.Command.TransferType())
|
|
}
|
|
|
|
if request.Security.Is(protocol.SecurityType_CHACHA20_POLY1305) {
|
|
aead, _ := chacha20poly1305.New(GenerateChacha20Poly1305Key(s.responseBodyKey))
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: aead,
|
|
NonceGenerator: &ChunkNonceGenerator{
|
|
Nonce: append([]byte(nil), s.responseBodyIV...),
|
|
Size: aead.NonceSize(),
|
|
},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
return crypto.NewAuthenticationWriter(auth, sizeParser, writer, request.Command.TransferType())
|
|
}
|
|
|
|
panic("Unknown security type.")
|
|
}
|