mirror of https://github.com/v2ray/v2ray-core
375 lines
11 KiB
Go
375 lines
11 KiB
Go
package encoding
|
|
|
|
import (
|
|
"context"
|
|
"crypto/aes"
|
|
"crypto/cipher"
|
|
"crypto/md5"
|
|
"hash/fnv"
|
|
"io"
|
|
"sync"
|
|
"time"
|
|
|
|
"golang.org/x/crypto/chacha20poly1305"
|
|
"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
|
|
token *signal.Semaphore
|
|
ctx context.Context
|
|
}
|
|
|
|
func NewSessionHistory(ctx context.Context) *SessionHistory {
|
|
h := &SessionHistory{
|
|
cache: make(map[sessionId]time.Time, 128),
|
|
token: signal.NewSemaphore(1),
|
|
ctx: ctx,
|
|
}
|
|
return h
|
|
}
|
|
|
|
func (h *SessionHistory) add(session sessionId) {
|
|
h.Lock()
|
|
h.cache[session] = time.Now().Add(time.Minute * 3)
|
|
|
|
select {
|
|
case <-h.token.Wait():
|
|
go h.run()
|
|
default:
|
|
}
|
|
|
|
h.Unlock()
|
|
}
|
|
|
|
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) run() {
|
|
defer h.token.Signal()
|
|
|
|
for {
|
|
select {
|
|
case <-h.ctx.Done():
|
|
return
|
|
case <-time.After(time.Second * 30):
|
|
}
|
|
session2Remove := make([]sessionId, 0, 16)
|
|
now := time.Now()
|
|
h.Lock()
|
|
if len(h.cache) == 0 {
|
|
h.Unlock()
|
|
return
|
|
}
|
|
for session, expire := range h.cache {
|
|
if expire.Before(now) {
|
|
session2Remove = append(session2Remove, session)
|
|
}
|
|
}
|
|
for _, session := range session2Remove {
|
|
delete(h.cache, session)
|
|
}
|
|
h.Unlock()
|
|
}
|
|
}
|
|
|
|
func getSizeMask(b []byte) crypto.Uint16Generator {
|
|
return crypto.NewShakeUint16Generator(b)
|
|
}
|
|
|
|
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 (v *ServerSession) DecodeRequestHeader(reader io.Reader) (*protocol.RequestHeader, error) {
|
|
buffer := make([]byte, 512)
|
|
|
|
_, err := io.ReadFull(reader, buffer[:protocol.IDBytesLen])
|
|
if err != nil {
|
|
return nil, newError("failed to read request header").Base(err)
|
|
}
|
|
|
|
user, timestamp, valid := v.userValidator.Get(buffer[:protocol.IDBytesLen])
|
|
if !valid {
|
|
return nil, newError("invalid user")
|
|
}
|
|
|
|
timestampHash := md5.New()
|
|
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)
|
|
|
|
nBytes, err := io.ReadFull(decryptor, buffer[:41])
|
|
if err != nil {
|
|
return nil, newError("failed to read request header").Base(err)
|
|
}
|
|
bufferLen := nBytes
|
|
|
|
request := &protocol.RequestHeader{
|
|
User: user,
|
|
Version: buffer[0],
|
|
}
|
|
|
|
if request.Version != Version {
|
|
return nil, newError("invalid protocol version ", request.Version)
|
|
}
|
|
|
|
v.requestBodyIV = append([]byte(nil), buffer[1:17]...) // 16 bytes
|
|
v.requestBodyKey = append([]byte(nil), buffer[17:33]...) // 16 bytes
|
|
var sid sessionId
|
|
copy(sid.user[:], vmessAccount.ID.Bytes())
|
|
copy(sid.key[:], v.requestBodyKey)
|
|
copy(sid.nonce[:], v.requestBodyIV)
|
|
if v.sessionHistory.has(sid) {
|
|
return nil, newError("duplicated session id, possibly under replay attack")
|
|
}
|
|
v.sessionHistory.add(sid)
|
|
|
|
v.responseHeader = buffer[33] // 1 byte
|
|
request.Option = protocol.RequestOption(buffer[34]) // 1 byte
|
|
padingLen := int(buffer[35] >> 4)
|
|
request.Security = protocol.NormSecurity(protocol.Security(buffer[35] & 0x0F))
|
|
// 1 bytes reserved
|
|
request.Command = protocol.RequestCommand(buffer[37])
|
|
|
|
request.Port = net.PortFromBytes(buffer[38:40])
|
|
|
|
switch buffer[40] {
|
|
case AddrTypeIPv4:
|
|
_, err = io.ReadFull(decryptor, buffer[41:45]) // 4 bytes
|
|
bufferLen += 4
|
|
if err != nil {
|
|
return nil, newError("failed to read IPv4 address").Base(err)
|
|
}
|
|
request.Address = net.IPAddress(buffer[41:45])
|
|
case AddrTypeIPv6:
|
|
_, err = io.ReadFull(decryptor, buffer[41:57]) // 16 bytes
|
|
bufferLen += 16
|
|
if err != nil {
|
|
return nil, newError("failed to read IPv6 address").Base(err)
|
|
}
|
|
request.Address = net.IPAddress(buffer[41:57])
|
|
case AddrTypeDomain:
|
|
_, err = io.ReadFull(decryptor, buffer[41:42])
|
|
if err != nil {
|
|
return nil, newError("failed to read domain address").Base(err)
|
|
}
|
|
domainLength := int(buffer[41])
|
|
if domainLength == 0 {
|
|
return nil, newError("zero length domain").Base(err)
|
|
}
|
|
_, err = io.ReadFull(decryptor, buffer[42:42+domainLength])
|
|
if err != nil {
|
|
return nil, newError("failed to read domain address").Base(err)
|
|
}
|
|
bufferLen += 1 + domainLength
|
|
request.Address = net.DomainAddress(string(buffer[42 : 42+domainLength]))
|
|
}
|
|
|
|
if padingLen > 0 {
|
|
_, err = io.ReadFull(decryptor, buffer[bufferLen:bufferLen+padingLen])
|
|
if err != nil {
|
|
return nil, newError("failed to read padding").Base(err)
|
|
}
|
|
bufferLen += padingLen
|
|
}
|
|
|
|
_, err = io.ReadFull(decryptor, buffer[bufferLen:bufferLen+4])
|
|
if err != nil {
|
|
return nil, newError("failed to read checksum").Base(err)
|
|
}
|
|
|
|
fnv1a := fnv.New32a()
|
|
fnv1a.Write(buffer[:bufferLen])
|
|
actualHash := fnv1a.Sum32()
|
|
expectedHash := serial.BytesToUint32(buffer[bufferLen : bufferLen+4])
|
|
|
|
if actualHash != expectedHash {
|
|
return nil, newError("invalid auth")
|
|
}
|
|
|
|
if request.Address == nil {
|
|
return nil, newError("invalid remote address")
|
|
}
|
|
|
|
return request, nil
|
|
}
|
|
|
|
func (v *ServerSession) DecodeRequestBody(request *protocol.RequestHeader, reader io.Reader) buf.Reader {
|
|
var authReader io.Reader
|
|
var sizeMask crypto.Uint16Generator = crypto.StaticUint16Generator(0)
|
|
if request.Option.Has(protocol.RequestOptionChunkMasking) {
|
|
sizeMask = getSizeMask(v.requestBodyIV)
|
|
}
|
|
if request.Security.Is(protocol.SecurityType_NONE) {
|
|
if request.Option.Has(protocol.RequestOptionChunkStream) {
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: NoOpAuthenticator{},
|
|
NonceGenerator: crypto.NoOpBytesGenerator{},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
authReader = crypto.NewAuthenticationReader(auth, reader, sizeMask)
|
|
} else {
|
|
authReader = reader
|
|
}
|
|
} else if request.Security.Is(protocol.SecurityType_LEGACY) {
|
|
aesStream := crypto.NewAesDecryptionStream(v.requestBodyKey, v.requestBodyIV)
|
|
cryptionReader := crypto.NewCryptionReader(aesStream, reader)
|
|
if request.Option.Has(protocol.RequestOptionChunkStream) {
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: new(FnvAuthenticator),
|
|
NonceGenerator: crypto.NoOpBytesGenerator{},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
authReader = crypto.NewAuthenticationReader(auth, cryptionReader, sizeMask)
|
|
} else {
|
|
authReader = cryptionReader
|
|
}
|
|
} else if request.Security.Is(protocol.SecurityType_AES128_GCM) {
|
|
block, _ := aes.NewCipher(v.requestBodyKey)
|
|
aead, _ := cipher.NewGCM(block)
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: aead,
|
|
NonceGenerator: &ChunkNonceGenerator{
|
|
Nonce: append([]byte(nil), v.requestBodyIV...),
|
|
Size: aead.NonceSize(),
|
|
},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
authReader = crypto.NewAuthenticationReader(auth, reader, sizeMask)
|
|
} else if request.Security.Is(protocol.SecurityType_CHACHA20_POLY1305) {
|
|
aead, _ := chacha20poly1305.New(GenerateChacha20Poly1305Key(v.requestBodyKey))
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: aead,
|
|
NonceGenerator: &ChunkNonceGenerator{
|
|
Nonce: append([]byte(nil), v.requestBodyIV...),
|
|
Size: aead.NonceSize(),
|
|
},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
authReader = crypto.NewAuthenticationReader(auth, reader, sizeMask)
|
|
}
|
|
|
|
return buf.NewReader(authReader)
|
|
}
|
|
|
|
func (v *ServerSession) EncodeResponseHeader(header *protocol.ResponseHeader, writer io.Writer) {
|
|
responseBodyKey := md5.Sum(v.requestBodyKey)
|
|
responseBodyIV := md5.Sum(v.requestBodyIV)
|
|
v.responseBodyKey = responseBodyKey[:]
|
|
v.responseBodyIV = responseBodyIV[:]
|
|
|
|
aesStream := crypto.NewAesEncryptionStream(v.responseBodyKey, v.responseBodyIV)
|
|
encryptionWriter := crypto.NewCryptionWriter(aesStream, writer)
|
|
v.responseWriter = encryptionWriter
|
|
|
|
encryptionWriter.Write([]byte{v.responseHeader, byte(header.Option)})
|
|
err := MarshalCommand(header.Command, encryptionWriter)
|
|
if err != nil {
|
|
encryptionWriter.Write([]byte{0x00, 0x00})
|
|
}
|
|
}
|
|
|
|
func (v *ServerSession) EncodeResponseBody(request *protocol.RequestHeader, writer io.Writer) buf.Writer {
|
|
var authWriter io.Writer
|
|
var sizeMask crypto.Uint16Generator = crypto.StaticUint16Generator(0)
|
|
if request.Option.Has(protocol.RequestOptionChunkMasking) {
|
|
sizeMask = getSizeMask(v.responseBodyIV)
|
|
}
|
|
if request.Security.Is(protocol.SecurityType_NONE) {
|
|
if request.Option.Has(protocol.RequestOptionChunkStream) {
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: NoOpAuthenticator{},
|
|
NonceGenerator: crypto.NoOpBytesGenerator{},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
authWriter = crypto.NewAuthenticationWriter(auth, writer, sizeMask)
|
|
} else {
|
|
authWriter = writer
|
|
}
|
|
} else 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{},
|
|
}
|
|
authWriter = crypto.NewAuthenticationWriter(auth, v.responseWriter, sizeMask)
|
|
} else {
|
|
authWriter = v.responseWriter
|
|
}
|
|
} else if request.Security.Is(protocol.SecurityType_AES128_GCM) {
|
|
block, _ := aes.NewCipher(v.responseBodyKey)
|
|
aead, _ := cipher.NewGCM(block)
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: aead,
|
|
NonceGenerator: &ChunkNonceGenerator{
|
|
Nonce: append([]byte(nil), v.responseBodyIV...),
|
|
Size: aead.NonceSize(),
|
|
},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
authWriter = crypto.NewAuthenticationWriter(auth, writer, sizeMask)
|
|
} else if request.Security.Is(protocol.SecurityType_CHACHA20_POLY1305) {
|
|
aead, _ := chacha20poly1305.New(GenerateChacha20Poly1305Key(v.responseBodyKey))
|
|
|
|
auth := &crypto.AEADAuthenticator{
|
|
AEAD: aead,
|
|
NonceGenerator: &ChunkNonceGenerator{
|
|
Nonce: append([]byte(nil), v.responseBodyIV...),
|
|
Size: aead.NonceSize(),
|
|
},
|
|
AdditionalDataGenerator: crypto.NoOpBytesGenerator{},
|
|
}
|
|
authWriter = crypto.NewAuthenticationWriter(auth, writer, sizeMask)
|
|
}
|
|
|
|
return buf.NewWriter(authWriter)
|
|
}
|