mirror of
https://github.com/v2fly/v2ray-core.git
synced 2024-09-05 19:44:32 -04:00
327 lines
8.4 KiB
Go
327 lines
8.4 KiB
Go
|
// Copyright 2012 The Go Authors. All rights reserved.
|
||
|
// Use of this source code is governed by a BSD-style
|
||
|
// license that can be found in the LICENSE file.
|
||
|
|
||
|
package qtls
|
||
|
|
||
|
import (
|
||
|
"bytes"
|
||
|
"crypto/aes"
|
||
|
"crypto/cipher"
|
||
|
"crypto/hmac"
|
||
|
"crypto/sha256"
|
||
|
"crypto/subtle"
|
||
|
"errors"
|
||
|
"io"
|
||
|
)
|
||
|
|
||
|
// A SessionTicketSealer provides a way to securely encapsulate
|
||
|
// session state for storage on the client. All methods are safe for
|
||
|
// concurrent use.
|
||
|
type SessionTicketSealer interface {
|
||
|
// Seal returns a session ticket value that can be later passed to Unseal
|
||
|
// to recover the content, usually by encrypting it. The ticket will be sent
|
||
|
// to the client to be stored, and will be sent back in plaintext, so it can
|
||
|
// be read and modified by an attacker.
|
||
|
Seal(cs *ConnectionState, content []byte) (ticket []byte, err error)
|
||
|
|
||
|
// Unseal returns a session ticket contents. The ticket can't be safely
|
||
|
// assumed to have been generated by Seal.
|
||
|
// If unable to unseal the ticket, the connection will proceed with a
|
||
|
// complete handshake.
|
||
|
Unseal(chi *ClientHelloInfo, ticket []byte) (content []byte, success bool)
|
||
|
}
|
||
|
|
||
|
// sessionState contains the information that is serialized into a session
|
||
|
// ticket in order to later resume a connection.
|
||
|
type sessionState struct {
|
||
|
vers uint16
|
||
|
cipherSuite uint16
|
||
|
usedEMS bool
|
||
|
masterSecret []byte
|
||
|
certificates [][]byte
|
||
|
// usedOldKey is true if the ticket from which this session came from
|
||
|
// was encrypted with an older key and thus should be refreshed.
|
||
|
usedOldKey bool
|
||
|
}
|
||
|
|
||
|
func (s *sessionState) equal(i interface{}) bool {
|
||
|
s1, ok := i.(*sessionState)
|
||
|
if !ok {
|
||
|
return false
|
||
|
}
|
||
|
|
||
|
if s.vers != s1.vers ||
|
||
|
s.usedEMS != s1.usedEMS ||
|
||
|
s.cipherSuite != s1.cipherSuite ||
|
||
|
!bytes.Equal(s.masterSecret, s1.masterSecret) {
|
||
|
return false
|
||
|
}
|
||
|
|
||
|
if len(s.certificates) != len(s1.certificates) {
|
||
|
return false
|
||
|
}
|
||
|
|
||
|
for i := range s.certificates {
|
||
|
if !bytes.Equal(s.certificates[i], s1.certificates[i]) {
|
||
|
return false
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return true
|
||
|
}
|
||
|
|
||
|
func (s *sessionState) marshal() []byte {
|
||
|
length := 2 + 2 + 2 + len(s.masterSecret) + 2
|
||
|
for _, cert := range s.certificates {
|
||
|
length += 4 + len(cert)
|
||
|
}
|
||
|
|
||
|
ret := make([]byte, length)
|
||
|
x := ret
|
||
|
was_used := byte(0)
|
||
|
if s.usedEMS {
|
||
|
was_used = byte(0x80)
|
||
|
}
|
||
|
|
||
|
x[0] = byte(s.vers>>8) | byte(was_used)
|
||
|
x[1] = byte(s.vers)
|
||
|
x[2] = byte(s.cipherSuite >> 8)
|
||
|
x[3] = byte(s.cipherSuite)
|
||
|
x[4] = byte(len(s.masterSecret) >> 8)
|
||
|
x[5] = byte(len(s.masterSecret))
|
||
|
x = x[6:]
|
||
|
copy(x, s.masterSecret)
|
||
|
x = x[len(s.masterSecret):]
|
||
|
|
||
|
x[0] = byte(len(s.certificates) >> 8)
|
||
|
x[1] = byte(len(s.certificates))
|
||
|
x = x[2:]
|
||
|
|
||
|
for _, cert := range s.certificates {
|
||
|
x[0] = byte(len(cert) >> 24)
|
||
|
x[1] = byte(len(cert) >> 16)
|
||
|
x[2] = byte(len(cert) >> 8)
|
||
|
x[3] = byte(len(cert))
|
||
|
copy(x[4:], cert)
|
||
|
x = x[4+len(cert):]
|
||
|
}
|
||
|
|
||
|
return ret
|
||
|
}
|
||
|
|
||
|
func (s *sessionState) unmarshal(data []byte) alert {
|
||
|
if len(data) < 8 {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
|
||
|
s.vers = (uint16(data[0])<<8 | uint16(data[1])) & 0x7fff
|
||
|
s.cipherSuite = uint16(data[2])<<8 | uint16(data[3])
|
||
|
s.usedEMS = (data[0] & 0x80) == 0x80
|
||
|
masterSecretLen := int(data[4])<<8 | int(data[5])
|
||
|
data = data[6:]
|
||
|
if len(data) < masterSecretLen {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
|
||
|
s.masterSecret = data[:masterSecretLen]
|
||
|
data = data[masterSecretLen:]
|
||
|
|
||
|
if len(data) < 2 {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
|
||
|
numCerts := int(data[0])<<8 | int(data[1])
|
||
|
data = data[2:]
|
||
|
|
||
|
s.certificates = make([][]byte, numCerts)
|
||
|
for i := range s.certificates {
|
||
|
if len(data) < 4 {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
certLen := int(data[0])<<24 | int(data[1])<<16 | int(data[2])<<8 | int(data[3])
|
||
|
data = data[4:]
|
||
|
if certLen < 0 {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
if len(data) < certLen {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
s.certificates[i] = data[:certLen]
|
||
|
data = data[certLen:]
|
||
|
}
|
||
|
|
||
|
if len(data) != 0 {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
return alertSuccess
|
||
|
}
|
||
|
|
||
|
type sessionState13 struct {
|
||
|
vers uint16
|
||
|
suite uint16
|
||
|
ageAdd uint32
|
||
|
createdAt uint64
|
||
|
maxEarlyDataLen uint32
|
||
|
pskSecret []byte
|
||
|
alpnProtocol string
|
||
|
SNI string
|
||
|
}
|
||
|
|
||
|
func (s *sessionState13) equal(i interface{}) bool {
|
||
|
s1, ok := i.(*sessionState13)
|
||
|
if !ok {
|
||
|
return false
|
||
|
}
|
||
|
|
||
|
return s.vers == s1.vers &&
|
||
|
s.suite == s1.suite &&
|
||
|
s.ageAdd == s1.ageAdd &&
|
||
|
s.createdAt == s1.createdAt &&
|
||
|
s.maxEarlyDataLen == s1.maxEarlyDataLen &&
|
||
|
subtle.ConstantTimeCompare(s.pskSecret, s1.pskSecret) == 1 &&
|
||
|
s.alpnProtocol == s1.alpnProtocol &&
|
||
|
s.SNI == s1.SNI
|
||
|
}
|
||
|
|
||
|
func (s *sessionState13) marshal() []byte {
|
||
|
length := 2 + 2 + 4 + 8 + 4 + 2 + len(s.pskSecret) + 2 + len(s.alpnProtocol) + 2 + len(s.SNI)
|
||
|
|
||
|
x := make([]byte, length)
|
||
|
x[0] = byte(s.vers >> 8)
|
||
|
x[1] = byte(s.vers)
|
||
|
x[2] = byte(s.suite >> 8)
|
||
|
x[3] = byte(s.suite)
|
||
|
x[4] = byte(s.ageAdd >> 24)
|
||
|
x[5] = byte(s.ageAdd >> 16)
|
||
|
x[6] = byte(s.ageAdd >> 8)
|
||
|
x[7] = byte(s.ageAdd)
|
||
|
x[8] = byte(s.createdAt >> 56)
|
||
|
x[9] = byte(s.createdAt >> 48)
|
||
|
x[10] = byte(s.createdAt >> 40)
|
||
|
x[11] = byte(s.createdAt >> 32)
|
||
|
x[12] = byte(s.createdAt >> 24)
|
||
|
x[13] = byte(s.createdAt >> 16)
|
||
|
x[14] = byte(s.createdAt >> 8)
|
||
|
x[15] = byte(s.createdAt)
|
||
|
x[16] = byte(s.maxEarlyDataLen >> 24)
|
||
|
x[17] = byte(s.maxEarlyDataLen >> 16)
|
||
|
x[18] = byte(s.maxEarlyDataLen >> 8)
|
||
|
x[19] = byte(s.maxEarlyDataLen)
|
||
|
x[20] = byte(len(s.pskSecret) >> 8)
|
||
|
x[21] = byte(len(s.pskSecret))
|
||
|
copy(x[22:], s.pskSecret)
|
||
|
z := x[22+len(s.pskSecret):]
|
||
|
z[0] = byte(len(s.alpnProtocol) >> 8)
|
||
|
z[1] = byte(len(s.alpnProtocol))
|
||
|
copy(z[2:], s.alpnProtocol)
|
||
|
z = z[2+len(s.alpnProtocol):]
|
||
|
z[0] = byte(len(s.SNI) >> 8)
|
||
|
z[1] = byte(len(s.SNI))
|
||
|
copy(z[2:], s.SNI)
|
||
|
|
||
|
return x
|
||
|
}
|
||
|
|
||
|
func (s *sessionState13) unmarshal(data []byte) alert {
|
||
|
if len(data) < 24 {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
|
||
|
s.vers = uint16(data[0])<<8 | uint16(data[1])
|
||
|
s.suite = uint16(data[2])<<8 | uint16(data[3])
|
||
|
s.ageAdd = uint32(data[4])<<24 | uint32(data[5])<<16 | uint32(data[6])<<8 | uint32(data[7])
|
||
|
s.createdAt = uint64(data[8])<<56 | uint64(data[9])<<48 | uint64(data[10])<<40 | uint64(data[11])<<32 |
|
||
|
uint64(data[12])<<24 | uint64(data[13])<<16 | uint64(data[14])<<8 | uint64(data[15])
|
||
|
s.maxEarlyDataLen = uint32(data[16])<<24 | uint32(data[17])<<16 | uint32(data[18])<<8 | uint32(data[19])
|
||
|
|
||
|
l := int(data[20])<<8 | int(data[21])
|
||
|
if len(data) < 22+l+2 {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
s.pskSecret = data[22 : 22+l]
|
||
|
z := data[22+l:]
|
||
|
|
||
|
l = int(z[0])<<8 | int(z[1])
|
||
|
if len(z) < 2+l+2 {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
s.alpnProtocol = string(z[2 : 2+l])
|
||
|
z = z[2+l:]
|
||
|
|
||
|
l = int(z[0])<<8 | int(z[1])
|
||
|
if len(z) != 2+l {
|
||
|
return alertDecodeError
|
||
|
}
|
||
|
s.SNI = string(z[2 : 2+l])
|
||
|
|
||
|
return alertSuccess
|
||
|
}
|
||
|
|
||
|
func (c *Conn) encryptTicket(serialized []byte) ([]byte, error) {
|
||
|
encrypted := make([]byte, ticketKeyNameLen+aes.BlockSize+len(serialized)+sha256.Size)
|
||
|
keyName := encrypted[:ticketKeyNameLen]
|
||
|
iv := encrypted[ticketKeyNameLen : ticketKeyNameLen+aes.BlockSize]
|
||
|
macBytes := encrypted[len(encrypted)-sha256.Size:]
|
||
|
|
||
|
if _, err := io.ReadFull(c.config.rand(), iv); err != nil {
|
||
|
return nil, err
|
||
|
}
|
||
|
key := c.config.ticketKeys()[0]
|
||
|
copy(keyName, key.keyName[:])
|
||
|
block, err := aes.NewCipher(key.aesKey[:])
|
||
|
if err != nil {
|
||
|
return nil, errors.New("tls: failed to create cipher while encrypting ticket: " + err.Error())
|
||
|
}
|
||
|
cipher.NewCTR(block, iv).XORKeyStream(encrypted[ticketKeyNameLen+aes.BlockSize:], serialized)
|
||
|
|
||
|
mac := hmac.New(sha256.New, key.hmacKey[:])
|
||
|
mac.Write(encrypted[:len(encrypted)-sha256.Size])
|
||
|
mac.Sum(macBytes[:0])
|
||
|
|
||
|
return encrypted, nil
|
||
|
}
|
||
|
|
||
|
func (c *Conn) decryptTicket(encrypted []byte) (serialized []byte, usedOldKey bool) {
|
||
|
if c.config.SessionTicketsDisabled ||
|
||
|
len(encrypted) < ticketKeyNameLen+aes.BlockSize+sha256.Size {
|
||
|
return nil, false
|
||
|
}
|
||
|
|
||
|
keyName := encrypted[:ticketKeyNameLen]
|
||
|
iv := encrypted[ticketKeyNameLen : ticketKeyNameLen+aes.BlockSize]
|
||
|
macBytes := encrypted[len(encrypted)-sha256.Size:]
|
||
|
|
||
|
keys := c.config.ticketKeys()
|
||
|
keyIndex := -1
|
||
|
for i, candidateKey := range keys {
|
||
|
if bytes.Equal(keyName, candidateKey.keyName[:]) {
|
||
|
keyIndex = i
|
||
|
break
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if keyIndex == -1 {
|
||
|
return nil, false
|
||
|
}
|
||
|
key := &keys[keyIndex]
|
||
|
|
||
|
mac := hmac.New(sha256.New, key.hmacKey[:])
|
||
|
mac.Write(encrypted[:len(encrypted)-sha256.Size])
|
||
|
expected := mac.Sum(nil)
|
||
|
|
||
|
if subtle.ConstantTimeCompare(macBytes, expected) != 1 {
|
||
|
return nil, false
|
||
|
}
|
||
|
|
||
|
block, err := aes.NewCipher(key.aesKey[:])
|
||
|
if err != nil {
|
||
|
return nil, false
|
||
|
}
|
||
|
ciphertext := encrypted[ticketKeyNameLen+aes.BlockSize : len(encrypted)-sha256.Size]
|
||
|
plaintext := ciphertext
|
||
|
cipher.NewCTR(block, iv).XORKeyStream(plaintext, ciphertext)
|
||
|
|
||
|
return plaintext, keyIndex > 0
|
||
|
}
|