TUN-3090: Upgrade crypto dep

This commit is contained in:
Adam Chalmers
2020-06-12 00:03:09 -05:00
parent ae8d784e36
commit 6e761cb7ae
65 changed files with 5603 additions and 3850 deletions

View File

@@ -17,12 +17,14 @@ import (
// These constants from [PROTOCOL.certkeys] represent the algorithm names
// for certificate types supported by this package.
const (
CertAlgoRSAv01 = "ssh-rsa-cert-v01@openssh.com"
CertAlgoDSAv01 = "ssh-dss-cert-v01@openssh.com"
CertAlgoECDSA256v01 = "ecdsa-sha2-nistp256-cert-v01@openssh.com"
CertAlgoECDSA384v01 = "ecdsa-sha2-nistp384-cert-v01@openssh.com"
CertAlgoECDSA521v01 = "ecdsa-sha2-nistp521-cert-v01@openssh.com"
CertAlgoED25519v01 = "ssh-ed25519-cert-v01@openssh.com"
CertAlgoRSAv01 = "ssh-rsa-cert-v01@openssh.com"
CertAlgoDSAv01 = "ssh-dss-cert-v01@openssh.com"
CertAlgoECDSA256v01 = "ecdsa-sha2-nistp256-cert-v01@openssh.com"
CertAlgoECDSA384v01 = "ecdsa-sha2-nistp384-cert-v01@openssh.com"
CertAlgoECDSA521v01 = "ecdsa-sha2-nistp521-cert-v01@openssh.com"
CertAlgoSKECDSA256v01 = "sk-ecdsa-sha2-nistp256-cert-v01@openssh.com"
CertAlgoED25519v01 = "ssh-ed25519-cert-v01@openssh.com"
CertAlgoSKED25519v01 = "sk-ssh-ed25519-cert-v01@openssh.com"
)
// Certificate types distinguish between host and user
@@ -37,6 +39,7 @@ const (
type Signature struct {
Format string
Blob []byte
Rest []byte `ssh:"rest"`
}
// CertTimeInfinity can be used for OpenSSHCertV01.ValidBefore to indicate that
@@ -411,8 +414,8 @@ func (c *CertChecker) CheckCert(principal string, cert *Certificate) error {
return nil
}
// SignCert sets c.SignatureKey to the authority's public key and stores a
// Signature, by authority, in the certificate.
// SignCert signs the certificate with an authority, setting the Nonce,
// SignatureKey, and Signature fields.
func (c *Certificate) SignCert(rand io.Reader, authority Signer) error {
c.Nonce = make([]byte, 32)
if _, err := io.ReadFull(rand, c.Nonce); err != nil {
@@ -429,12 +432,14 @@ func (c *Certificate) SignCert(rand io.Reader, authority Signer) error {
}
var certAlgoNames = map[string]string{
KeyAlgoRSA: CertAlgoRSAv01,
KeyAlgoDSA: CertAlgoDSAv01,
KeyAlgoECDSA256: CertAlgoECDSA256v01,
KeyAlgoECDSA384: CertAlgoECDSA384v01,
KeyAlgoECDSA521: CertAlgoECDSA521v01,
KeyAlgoED25519: CertAlgoED25519v01,
KeyAlgoRSA: CertAlgoRSAv01,
KeyAlgoDSA: CertAlgoDSAv01,
KeyAlgoECDSA256: CertAlgoECDSA256v01,
KeyAlgoECDSA384: CertAlgoECDSA384v01,
KeyAlgoECDSA521: CertAlgoECDSA521v01,
KeyAlgoSKECDSA256: CertAlgoSKECDSA256v01,
KeyAlgoED25519: CertAlgoED25519v01,
KeyAlgoSKED25519: CertAlgoSKED25519v01,
}
// certToPrivAlgo returns the underlying algorithm for a certificate algorithm.
@@ -518,6 +523,12 @@ func parseSignatureBody(in []byte) (out *Signature, rest []byte, ok bool) {
return
}
switch out.Format {
case KeyAlgoSKECDSA256, CertAlgoSKECDSA256v01, KeyAlgoSKED25519, CertAlgoSKED25519v01:
out.Rest = in
return out, nil, ok
}
return out, in, ok
}

View File

@@ -16,9 +16,8 @@ import (
"hash"
"io"
"io/ioutil"
"math/bits"
"golang.org/x/crypto/internal/chacha20"
"golang.org/x/crypto/chacha20"
"golang.org/x/crypto/poly1305"
)
@@ -120,7 +119,7 @@ var cipherModes = map[string]*cipherMode{
chacha20Poly1305ID: {64, 0, newChaCha20Cipher},
// CBC mode is insecure and so is not included in the default config.
// (See http://www.isg.rhul.ac.uk/~kp/SandPfinal.pdf). If absolutely
// (See https://www.ieee-security.org/TC/SP2013/papers/4977a526.pdf). If absolutely
// needed, it's possible to specify a custom Config to enable it.
// You should expect that an active attacker can recover plaintext if
// you do.
@@ -642,8 +641,8 @@ const chacha20Poly1305ID = "chacha20-poly1305@openssh.com"
// the methods here also implement padding, which RFC4253 Section 6
// also requires of stream ciphers.
type chacha20Poly1305Cipher struct {
lengthKey [8]uint32
contentKey [8]uint32
lengthKey [32]byte
contentKey [32]byte
buf []byte
}
@@ -656,21 +655,21 @@ func newChaCha20Cipher(key, unusedIV, unusedMACKey []byte, unusedAlgs directionA
buf: make([]byte, 256),
}
for i := range c.contentKey {
c.contentKey[i] = binary.LittleEndian.Uint32(key[i*4 : (i+1)*4])
}
for i := range c.lengthKey {
c.lengthKey[i] = binary.LittleEndian.Uint32(key[(i+8)*4 : (i+9)*4])
}
copy(c.contentKey[:], key[:32])
copy(c.lengthKey[:], key[32:])
return c, nil
}
func (c *chacha20Poly1305Cipher) readCipherPacket(seqNum uint32, r io.Reader) ([]byte, error) {
nonce := [3]uint32{0, 0, bits.ReverseBytes32(seqNum)}
s := chacha20.New(c.contentKey, nonce)
var polyKey [32]byte
nonce := make([]byte, 12)
binary.BigEndian.PutUint32(nonce[8:], seqNum)
s, err := chacha20.NewUnauthenticatedCipher(c.contentKey[:], nonce)
if err != nil {
return nil, err
}
var polyKey, discardBuf [32]byte
s.XORKeyStream(polyKey[:], polyKey[:])
s.Advance() // skip next 32 bytes
s.XORKeyStream(discardBuf[:], discardBuf[:]) // skip the next 32 bytes
encryptedLength := c.buf[:4]
if _, err := io.ReadFull(r, encryptedLength); err != nil {
@@ -678,7 +677,11 @@ func (c *chacha20Poly1305Cipher) readCipherPacket(seqNum uint32, r io.Reader) ([
}
var lenBytes [4]byte
chacha20.New(c.lengthKey, nonce).XORKeyStream(lenBytes[:], encryptedLength)
ls, err := chacha20.NewUnauthenticatedCipher(c.lengthKey[:], nonce)
if err != nil {
return nil, err
}
ls.XORKeyStream(lenBytes[:], encryptedLength)
length := binary.BigEndian.Uint32(lenBytes[:])
if length > maxPacket {
@@ -724,11 +727,15 @@ func (c *chacha20Poly1305Cipher) readCipherPacket(seqNum uint32, r io.Reader) ([
}
func (c *chacha20Poly1305Cipher) writeCipherPacket(seqNum uint32, w io.Writer, rand io.Reader, payload []byte) error {
nonce := [3]uint32{0, 0, bits.ReverseBytes32(seqNum)}
s := chacha20.New(c.contentKey, nonce)
var polyKey [32]byte
nonce := make([]byte, 12)
binary.BigEndian.PutUint32(nonce[8:], seqNum)
s, err := chacha20.NewUnauthenticatedCipher(c.contentKey[:], nonce)
if err != nil {
return err
}
var polyKey, discardBuf [32]byte
s.XORKeyStream(polyKey[:], polyKey[:])
s.Advance() // skip next 32 bytes
s.XORKeyStream(discardBuf[:], discardBuf[:]) // skip the next 32 bytes
// There is no blocksize, so fall back to multiple of 8 byte
// padding, as described in RFC 4253, Sec 6.
@@ -748,7 +755,11 @@ func (c *chacha20Poly1305Cipher) writeCipherPacket(seqNum uint32, w io.Writer, r
}
binary.BigEndian.PutUint32(c.buf, uint32(1+len(payload)+padding))
chacha20.New(c.lengthKey, nonce).XORKeyStream(c.buf, c.buf[:4])
ls, err := chacha20.NewUnauthenticatedCipher(c.lengthKey[:], nonce)
if err != nil {
return err
}
ls.XORKeyStream(c.buf, c.buf[:4])
c.buf[4] = byte(padding)
copy(c.buf[5:], payload)
packetEnd := 5 + len(payload) + padding

View File

@@ -0,0 +1,93 @@
// Copyright 2014 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 bcrypt_pbkdf implements bcrypt_pbkdf(3) from OpenBSD.
//
// See https://flak.tedunangst.com/post/bcrypt-pbkdf and
// https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libutil/bcrypt_pbkdf.c.
package bcrypt_pbkdf
import (
"crypto/sha512"
"errors"
"golang.org/x/crypto/blowfish"
)
const blockSize = 32
// Key derives a key from the password, salt and rounds count, returning a
// []byte of length keyLen that can be used as cryptographic key.
func Key(password, salt []byte, rounds, keyLen int) ([]byte, error) {
if rounds < 1 {
return nil, errors.New("bcrypt_pbkdf: number of rounds is too small")
}
if len(password) == 0 {
return nil, errors.New("bcrypt_pbkdf: empty password")
}
if len(salt) == 0 || len(salt) > 1<<20 {
return nil, errors.New("bcrypt_pbkdf: bad salt length")
}
if keyLen > 1024 {
return nil, errors.New("bcrypt_pbkdf: keyLen is too large")
}
numBlocks := (keyLen + blockSize - 1) / blockSize
key := make([]byte, numBlocks*blockSize)
h := sha512.New()
h.Write(password)
shapass := h.Sum(nil)
shasalt := make([]byte, 0, sha512.Size)
cnt, tmp := make([]byte, 4), make([]byte, blockSize)
for block := 1; block <= numBlocks; block++ {
h.Reset()
h.Write(salt)
cnt[0] = byte(block >> 24)
cnt[1] = byte(block >> 16)
cnt[2] = byte(block >> 8)
cnt[3] = byte(block)
h.Write(cnt)
bcryptHash(tmp, shapass, h.Sum(shasalt))
out := make([]byte, blockSize)
copy(out, tmp)
for i := 2; i <= rounds; i++ {
h.Reset()
h.Write(tmp)
bcryptHash(tmp, shapass, h.Sum(shasalt))
for j := 0; j < len(out); j++ {
out[j] ^= tmp[j]
}
}
for i, v := range out {
key[i*numBlocks+(block-1)] = v
}
}
return key[:keyLen], nil
}
var magic = []byte("OxychromaticBlowfishSwatDynamite")
func bcryptHash(out, shapass, shasalt []byte) {
c, err := blowfish.NewSaltedCipher(shapass, shasalt)
if err != nil {
panic(err)
}
for i := 0; i < 64; i++ {
blowfish.ExpandKey(shasalt, c)
blowfish.ExpandKey(shapass, c)
}
copy(out, magic)
for i := 0; i < 32; i += 8 {
for j := 0; j < 64; j++ {
c.Encrypt(out[i:i+8], out[i:i+8])
}
}
// Swap bytes due to different endianness.
for i := 0; i < 32; i += 4 {
out[i+3], out[i+2], out[i+1], out[i] = out[i], out[i+1], out[i+2], out[i+3]
}
}

View File

@@ -212,7 +212,7 @@ func (group *dhGroup) Server(c packetConn, randSource io.Reader, magics *handsha
HostKey: hostKeyBytes,
Signature: sig,
Hash: crypto.SHA1,
}, nil
}, err
}
// ecdh performs Elliptic Curve Diffie-Hellman key exchange as
@@ -572,7 +572,7 @@ func (gex *dhGEXSHA) diffieHellman(theirPublic, myPrivate *big.Int) (*big.Int, e
return new(big.Int).Exp(theirPublic, myPrivate, gex.p), nil
}
func (gex *dhGEXSHA) Client(c packetConn, randSource io.Reader, magics *handshakeMagics) (*kexResult, error) {
func (gex dhGEXSHA) Client(c packetConn, randSource io.Reader, magics *handshakeMagics) (*kexResult, error) {
// Send GexRequest
kexDHGexRequest := kexDHGexRequestMsg{
MinBits: dhGroupExchangeMinimumBits,
@@ -677,7 +677,7 @@ func (gex *dhGEXSHA) Client(c packetConn, randSource io.Reader, magics *handshak
// Server half implementation of the Diffie Hellman Key Exchange with SHA1 and SHA256.
//
// This is a minimal implementation to satisfy the automated tests.
func (gex *dhGEXSHA) Server(c packetConn, randSource io.Reader, magics *handshakeMagics, priv Signer) (result *kexResult, err error) {
func (gex dhGEXSHA) Server(c packetConn, randSource io.Reader, magics *handshakeMagics, priv Signer) (result *kexResult, err error) {
// Receive GexRequest
packet, err := c.readPacket()
if err != nil {

View File

@@ -7,6 +7,8 @@ package ssh
import (
"bytes"
"crypto"
"crypto/aes"
"crypto/cipher"
"crypto/dsa"
"crypto/ecdsa"
"crypto/elliptic"
@@ -25,17 +27,20 @@ import (
"strings"
"golang.org/x/crypto/ed25519"
"golang.org/x/crypto/ssh/internal/bcrypt_pbkdf"
)
// These constants represent the algorithm names for key types supported by this
// package.
const (
KeyAlgoRSA = "ssh-rsa"
KeyAlgoDSA = "ssh-dss"
KeyAlgoECDSA256 = "ecdsa-sha2-nistp256"
KeyAlgoECDSA384 = "ecdsa-sha2-nistp384"
KeyAlgoECDSA521 = "ecdsa-sha2-nistp521"
KeyAlgoED25519 = "ssh-ed25519"
KeyAlgoRSA = "ssh-rsa"
KeyAlgoDSA = "ssh-dss"
KeyAlgoECDSA256 = "ecdsa-sha2-nistp256"
KeyAlgoSKECDSA256 = "sk-ecdsa-sha2-nistp256@openssh.com"
KeyAlgoECDSA384 = "ecdsa-sha2-nistp384"
KeyAlgoECDSA521 = "ecdsa-sha2-nistp521"
KeyAlgoED25519 = "ssh-ed25519"
KeyAlgoSKED25519 = "sk-ssh-ed25519@openssh.com"
)
// These constants represent non-default signature algorithms that are supported
@@ -58,9 +63,13 @@ func parsePubKey(in []byte, algo string) (pubKey PublicKey, rest []byte, err err
return parseDSA(in)
case KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521:
return parseECDSA(in)
case KeyAlgoSKECDSA256:
return parseSKECDSA(in)
case KeyAlgoED25519:
return parseED25519(in)
case CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoED25519v01:
case KeyAlgoSKED25519:
return parseSKEd25519(in)
case CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoSKECDSA256v01, CertAlgoED25519v01, CertAlgoSKED25519v01:
cert, err := parseCert(in, certToPrivAlgo(algo))
if err != nil {
return nil, nil, err
@@ -553,9 +562,11 @@ func parseED25519(in []byte) (out PublicKey, rest []byte, err error) {
return nil, nil, err
}
key := ed25519.PublicKey(w.KeyBytes)
if l := len(w.KeyBytes); l != ed25519.PublicKeySize {
return nil, nil, fmt.Errorf("invalid size %d for Ed25519 public key", l)
}
return (ed25519PublicKey)(key), w.Rest, nil
return ed25519PublicKey(w.KeyBytes), w.Rest, nil
}
func (k ed25519PublicKey) Marshal() []byte {
@@ -573,9 +584,11 @@ func (k ed25519PublicKey) Verify(b []byte, sig *Signature) error {
if sig.Format != k.Type() {
return fmt.Errorf("ssh: signature type %s for key type %s", sig.Format, k.Type())
}
if l := len(k); l != ed25519.PublicKeySize {
return fmt.Errorf("ssh: invalid size %d for Ed25519 public key", l)
}
edKey := (ed25519.PublicKey)(k)
if ok := ed25519.Verify(edKey, b, sig.Blob); !ok {
if ok := ed25519.Verify(ed25519.PublicKey(k), b, sig.Blob); !ok {
return errors.New("ssh: signature did not verify")
}
@@ -685,6 +698,224 @@ func (k *ecdsaPublicKey) CryptoPublicKey() crypto.PublicKey {
return (*ecdsa.PublicKey)(k)
}
// skFields holds the additional fields present in U2F/FIDO2 signatures.
// See openssh/PROTOCOL.u2f 'SSH U2F Signatures' for details.
type skFields struct {
// Flags contains U2F/FIDO2 flags such as 'user present'
Flags byte
// Counter is a monotonic signature counter which can be
// used to detect concurrent use of a private key, should
// it be extracted from hardware.
Counter uint32
}
type skECDSAPublicKey struct {
// application is a URL-like string, typically "ssh:" for SSH.
// see openssh/PROTOCOL.u2f for details.
application string
ecdsa.PublicKey
}
func (k *skECDSAPublicKey) Type() string {
return KeyAlgoSKECDSA256
}
func (k *skECDSAPublicKey) nistID() string {
return "nistp256"
}
func parseSKECDSA(in []byte) (out PublicKey, rest []byte, err error) {
var w struct {
Curve string
KeyBytes []byte
Application string
Rest []byte `ssh:"rest"`
}
if err := Unmarshal(in, &w); err != nil {
return nil, nil, err
}
key := new(skECDSAPublicKey)
key.application = w.Application
if w.Curve != "nistp256" {
return nil, nil, errors.New("ssh: unsupported curve")
}
key.Curve = elliptic.P256()
key.X, key.Y = elliptic.Unmarshal(key.Curve, w.KeyBytes)
if key.X == nil || key.Y == nil {
return nil, nil, errors.New("ssh: invalid curve point")
}
return key, w.Rest, nil
}
func (k *skECDSAPublicKey) Marshal() []byte {
// See RFC 5656, section 3.1.
keyBytes := elliptic.Marshal(k.Curve, k.X, k.Y)
w := struct {
Name string
ID string
Key []byte
Application string
}{
k.Type(),
k.nistID(),
keyBytes,
k.application,
}
return Marshal(&w)
}
func (k *skECDSAPublicKey) Verify(data []byte, sig *Signature) error {
if sig.Format != k.Type() {
return fmt.Errorf("ssh: signature type %s for key type %s", sig.Format, k.Type())
}
h := ecHash(k.Curve).New()
h.Write([]byte(k.application))
appDigest := h.Sum(nil)
h.Reset()
h.Write(data)
dataDigest := h.Sum(nil)
var ecSig struct {
R *big.Int
S *big.Int
}
if err := Unmarshal(sig.Blob, &ecSig); err != nil {
return err
}
var skf skFields
if err := Unmarshal(sig.Rest, &skf); err != nil {
return err
}
blob := struct {
ApplicationDigest []byte `ssh:"rest"`
Flags byte
Counter uint32
MessageDigest []byte `ssh:"rest"`
}{
appDigest,
skf.Flags,
skf.Counter,
dataDigest,
}
original := Marshal(blob)
h.Reset()
h.Write(original)
digest := h.Sum(nil)
if ecdsa.Verify((*ecdsa.PublicKey)(&k.PublicKey), digest, ecSig.R, ecSig.S) {
return nil
}
return errors.New("ssh: signature did not verify")
}
type skEd25519PublicKey struct {
// application is a URL-like string, typically "ssh:" for SSH.
// see openssh/PROTOCOL.u2f for details.
application string
ed25519.PublicKey
}
func (k *skEd25519PublicKey) Type() string {
return KeyAlgoSKED25519
}
func parseSKEd25519(in []byte) (out PublicKey, rest []byte, err error) {
var w struct {
KeyBytes []byte
Application string
Rest []byte `ssh:"rest"`
}
if err := Unmarshal(in, &w); err != nil {
return nil, nil, err
}
if l := len(w.KeyBytes); l != ed25519.PublicKeySize {
return nil, nil, fmt.Errorf("invalid size %d for Ed25519 public key", l)
}
key := new(skEd25519PublicKey)
key.application = w.Application
key.PublicKey = ed25519.PublicKey(w.KeyBytes)
return key, w.Rest, nil
}
func (k *skEd25519PublicKey) Marshal() []byte {
w := struct {
Name string
KeyBytes []byte
Application string
}{
KeyAlgoSKED25519,
[]byte(k.PublicKey),
k.application,
}
return Marshal(&w)
}
func (k *skEd25519PublicKey) Verify(data []byte, sig *Signature) error {
if sig.Format != k.Type() {
return fmt.Errorf("ssh: signature type %s for key type %s", sig.Format, k.Type())
}
if l := len(k.PublicKey); l != ed25519.PublicKeySize {
return fmt.Errorf("invalid size %d for Ed25519 public key", l)
}
h := sha256.New()
h.Write([]byte(k.application))
appDigest := h.Sum(nil)
h.Reset()
h.Write(data)
dataDigest := h.Sum(nil)
var edSig struct {
Signature []byte `ssh:"rest"`
}
if err := Unmarshal(sig.Blob, &edSig); err != nil {
return err
}
var skf skFields
if err := Unmarshal(sig.Rest, &skf); err != nil {
return err
}
blob := struct {
ApplicationDigest []byte `ssh:"rest"`
Flags byte
Counter uint32
MessageDigest []byte `ssh:"rest"`
}{
appDigest,
skf.Flags,
skf.Counter,
dataDigest,
}
original := Marshal(blob)
if ok := ed25519.Verify(k.PublicKey, original, edSig.Signature); !ok {
return errors.New("ssh: signature did not verify")
}
return nil
}
// NewSignerFromKey takes an *rsa.PrivateKey, *dsa.PrivateKey,
// *ecdsa.PrivateKey or any other crypto.Signer and returns a
// corresponding Signer instance. ECDSA keys must use P-256, P-384 or
@@ -830,14 +1061,18 @@ func NewPublicKey(key interface{}) (PublicKey, error) {
case *dsa.PublicKey:
return (*dsaPublicKey)(key), nil
case ed25519.PublicKey:
return (ed25519PublicKey)(key), nil
if l := len(key); l != ed25519.PublicKeySize {
return nil, fmt.Errorf("ssh: invalid size %d for Ed25519 public key", l)
}
return ed25519PublicKey(key), nil
default:
return nil, fmt.Errorf("ssh: unsupported key type %T", key)
}
}
// ParsePrivateKey returns a Signer from a PEM encoded private key. It supports
// the same keys as ParseRawPrivateKey.
// the same keys as ParseRawPrivateKey. If the private key is encrypted, it
// will return a PassphraseMissingError.
func ParsePrivateKey(pemBytes []byte) (Signer, error) {
key, err := ParseRawPrivateKey(pemBytes)
if err != nil {
@@ -850,8 +1085,8 @@ func ParsePrivateKey(pemBytes []byte) (Signer, error) {
// ParsePrivateKeyWithPassphrase returns a Signer from a PEM encoded private
// key and passphrase. It supports the same keys as
// ParseRawPrivateKeyWithPassphrase.
func ParsePrivateKeyWithPassphrase(pemBytes, passPhrase []byte) (Signer, error) {
key, err := ParseRawPrivateKeyWithPassphrase(pemBytes, passPhrase)
func ParsePrivateKeyWithPassphrase(pemBytes, passphrase []byte) (Signer, error) {
key, err := ParseRawPrivateKeyWithPassphrase(pemBytes, passphrase)
if err != nil {
return nil, err
}
@@ -867,8 +1102,21 @@ func encryptedBlock(block *pem.Block) bool {
return strings.Contains(block.Headers["Proc-Type"], "ENCRYPTED")
}
// A PassphraseMissingError indicates that parsing this private key requires a
// passphrase. Use ParsePrivateKeyWithPassphrase.
type PassphraseMissingError struct {
// PublicKey will be set if the private key format includes an unencrypted
// public key along with the encrypted private key.
PublicKey PublicKey
}
func (*PassphraseMissingError) Error() string {
return "ssh: this private key is passphrase protected"
}
// ParseRawPrivateKey returns a private key from a PEM encoded private key. It
// supports RSA (PKCS#1), PKCS#8, DSA (OpenSSL), and ECDSA private keys.
// supports RSA (PKCS#1), PKCS#8, DSA (OpenSSL), and ECDSA private keys. If the
// private key is encrypted, it will return a PassphraseMissingError.
func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
block, _ := pem.Decode(pemBytes)
if block == nil {
@@ -876,7 +1124,7 @@ func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
}
if encryptedBlock(block) {
return nil, errors.New("ssh: cannot decode encrypted private keys")
return nil, &PassphraseMissingError{}
}
switch block.Type {
@@ -890,33 +1138,35 @@ func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
case "DSA PRIVATE KEY":
return ParseDSAPrivateKey(block.Bytes)
case "OPENSSH PRIVATE KEY":
return parseOpenSSHPrivateKey(block.Bytes)
return parseOpenSSHPrivateKey(block.Bytes, unencryptedOpenSSHKey)
default:
return nil, fmt.Errorf("ssh: unsupported key type %q", block.Type)
}
}
// ParseRawPrivateKeyWithPassphrase returns a private key decrypted with
// passphrase from a PEM encoded private key. If wrong passphrase, return
// x509.IncorrectPasswordError.
func ParseRawPrivateKeyWithPassphrase(pemBytes, passPhrase []byte) (interface{}, error) {
// passphrase from a PEM encoded private key. If the passphrase is wrong, it
// will return x509.IncorrectPasswordError.
func ParseRawPrivateKeyWithPassphrase(pemBytes, passphrase []byte) (interface{}, error) {
block, _ := pem.Decode(pemBytes)
if block == nil {
return nil, errors.New("ssh: no key found")
}
buf := block.Bytes
if encryptedBlock(block) {
if x509.IsEncryptedPEMBlock(block) {
var err error
buf, err = x509.DecryptPEMBlock(block, passPhrase)
if err != nil {
if err == x509.IncorrectPasswordError {
return nil, err
}
return nil, fmt.Errorf("ssh: cannot decode encrypted private keys: %v", err)
}
if block.Type == "OPENSSH PRIVATE KEY" {
return parseOpenSSHPrivateKey(block.Bytes, passphraseProtectedOpenSSHKey(passphrase))
}
if !encryptedBlock(block) || !x509.IsEncryptedPEMBlock(block) {
return nil, errors.New("ssh: not an encrypted key")
}
buf, err := x509.DecryptPEMBlock(block, passphrase)
if err != nil {
if err == x509.IncorrectPasswordError {
return nil, err
}
return nil, fmt.Errorf("ssh: cannot decode encrypted private keys: %v", err)
}
switch block.Type {
@@ -926,8 +1176,6 @@ func ParseRawPrivateKeyWithPassphrase(pemBytes, passPhrase []byte) (interface{},
return x509.ParseECPrivateKey(buf)
case "DSA PRIVATE KEY":
return ParseDSAPrivateKey(buf)
case "OPENSSH PRIVATE KEY":
return parseOpenSSHPrivateKey(buf)
default:
return nil, fmt.Errorf("ssh: unsupported key type %q", block.Type)
}
@@ -965,9 +1213,68 @@ func ParseDSAPrivateKey(der []byte) (*dsa.PrivateKey, error) {
}, nil
}
// Implemented based on the documentation at
// https://github.com/openssh/openssh-portable/blob/master/PROTOCOL.key
func parseOpenSSHPrivateKey(key []byte) (crypto.PrivateKey, error) {
func unencryptedOpenSSHKey(cipherName, kdfName, kdfOpts string, privKeyBlock []byte) ([]byte, error) {
if kdfName != "none" || cipherName != "none" {
return nil, &PassphraseMissingError{}
}
if kdfOpts != "" {
return nil, errors.New("ssh: invalid openssh private key")
}
return privKeyBlock, nil
}
func passphraseProtectedOpenSSHKey(passphrase []byte) openSSHDecryptFunc {
return func(cipherName, kdfName, kdfOpts string, privKeyBlock []byte) ([]byte, error) {
if kdfName == "none" || cipherName == "none" {
return nil, errors.New("ssh: key is not password protected")
}
if kdfName != "bcrypt" {
return nil, fmt.Errorf("ssh: unknown KDF %q, only supports %q", kdfName, "bcrypt")
}
var opts struct {
Salt string
Rounds uint32
}
if err := Unmarshal([]byte(kdfOpts), &opts); err != nil {
return nil, err
}
k, err := bcrypt_pbkdf.Key(passphrase, []byte(opts.Salt), int(opts.Rounds), 32+16)
if err != nil {
return nil, err
}
key, iv := k[:32], k[32:]
c, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
switch cipherName {
case "aes256-ctr":
ctr := cipher.NewCTR(c, iv)
ctr.XORKeyStream(privKeyBlock, privKeyBlock)
case "aes256-cbc":
if len(privKeyBlock)%c.BlockSize() != 0 {
return nil, fmt.Errorf("ssh: invalid encrypted private key length, not a multiple of the block size")
}
cbc := cipher.NewCBCDecrypter(c, iv)
cbc.CryptBlocks(privKeyBlock, privKeyBlock)
default:
return nil, fmt.Errorf("ssh: unknown cipher %q, only supports %q or %q", cipherName, "aes256-ctr", "aes256-cbc")
}
return privKeyBlock, nil
}
}
type openSSHDecryptFunc func(CipherName, KdfName, KdfOpts string, PrivKeyBlock []byte) ([]byte, error)
// parseOpenSSHPrivateKey parses an OpenSSH private key, using the decrypt
// function to unwrap the encrypted portion. unencryptedOpenSSHKey can be used
// as the decrypt function to parse an unencrypted private key. See
// https://github.com/openssh/openssh-portable/blob/master/PROTOCOL.key.
func parseOpenSSHPrivateKey(key []byte, decrypt openSSHDecryptFunc) (crypto.PrivateKey, error) {
const magic = "openssh-key-v1\x00"
if len(key) < len(magic) || string(key[:len(magic)]) != magic {
return nil, errors.New("ssh: invalid openssh private key format")
@@ -986,9 +1293,22 @@ func parseOpenSSHPrivateKey(key []byte) (crypto.PrivateKey, error) {
if err := Unmarshal(remaining, &w); err != nil {
return nil, err
}
if w.NumKeys != 1 {
// We only support single key files, and so does OpenSSH.
// https://github.com/openssh/openssh-portable/blob/4103a3ec7/sshkey.c#L4171
return nil, errors.New("ssh: multi-key files are not supported")
}
if w.KdfName != "none" || w.CipherName != "none" {
return nil, errors.New("ssh: cannot decode encrypted private keys")
privKeyBlock, err := decrypt(w.CipherName, w.KdfName, w.KdfOpts, w.PrivKeyBlock)
if err != nil {
if err, ok := err.(*PassphraseMissingError); ok {
pub, errPub := ParsePublicKey(w.PubKey)
if errPub != nil {
return nil, fmt.Errorf("ssh: failed to parse embedded public key: %v", errPub)
}
err.PublicKey = pub
}
return nil, err
}
pk1 := struct {
@@ -998,15 +1318,13 @@ func parseOpenSSHPrivateKey(key []byte) (crypto.PrivateKey, error) {
Rest []byte `ssh:"rest"`
}{}
if err := Unmarshal(w.PrivKeyBlock, &pk1); err != nil {
return nil, err
if err := Unmarshal(privKeyBlock, &pk1); err != nil || pk1.Check1 != pk1.Check2 {
if w.CipherName != "none" {
return nil, x509.IncorrectPasswordError
}
return nil, errors.New("ssh: malformed OpenSSH key")
}
if pk1.Check1 != pk1.Check2 {
return nil, errors.New("ssh: checkint mismatch")
}
// we only handle ed25519 and rsa keys currently
switch pk1.Keytype {
case KeyAlgoRSA:
// https://github.com/openssh/openssh-portable/blob/master/sshkey.c#L2760-L2773
@@ -1025,10 +1343,8 @@ func parseOpenSSHPrivateKey(key []byte) (crypto.PrivateKey, error) {
return nil, err
}
for i, b := range key.Pad {
if int(b) != i+1 {
return nil, errors.New("ssh: padding not as expected")
}
if err := checkOpenSSHKeyPadding(key.Pad); err != nil {
return nil, err
}
pk := &rsa.PrivateKey{
@@ -1063,20 +1379,78 @@ func parseOpenSSHPrivateKey(key []byte) (crypto.PrivateKey, error) {
return nil, errors.New("ssh: private key unexpected length")
}
for i, b := range key.Pad {
if int(b) != i+1 {
return nil, errors.New("ssh: padding not as expected")
}
if err := checkOpenSSHKeyPadding(key.Pad); err != nil {
return nil, err
}
pk := ed25519.PrivateKey(make([]byte, ed25519.PrivateKeySize))
copy(pk, key.Priv)
return &pk, nil
case KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521:
key := struct {
Curve string
Pub []byte
D *big.Int
Comment string
Pad []byte `ssh:"rest"`
}{}
if err := Unmarshal(pk1.Rest, &key); err != nil {
return nil, err
}
if err := checkOpenSSHKeyPadding(key.Pad); err != nil {
return nil, err
}
var curve elliptic.Curve
switch key.Curve {
case "nistp256":
curve = elliptic.P256()
case "nistp384":
curve = elliptic.P384()
case "nistp521":
curve = elliptic.P521()
default:
return nil, errors.New("ssh: unhandled elliptic curve: " + key.Curve)
}
X, Y := elliptic.Unmarshal(curve, key.Pub)
if X == nil || Y == nil {
return nil, errors.New("ssh: failed to unmarshal public key")
}
if key.D.Cmp(curve.Params().N) >= 0 {
return nil, errors.New("ssh: scalar is out of range")
}
x, y := curve.ScalarBaseMult(key.D.Bytes())
if x.Cmp(X) != 0 || y.Cmp(Y) != 0 {
return nil, errors.New("ssh: public key does not match private key")
}
return &ecdsa.PrivateKey{
PublicKey: ecdsa.PublicKey{
Curve: curve,
X: X,
Y: Y,
},
D: key.D,
}, nil
default:
return nil, errors.New("ssh: unhandled key type")
}
}
func checkOpenSSHKeyPadding(pad []byte) error {
for i, b := range pad {
if int(b) != i+1 {
return errors.New("ssh: padding not as expected")
}
}
return nil
}
// FingerprintLegacyMD5 returns the user presentation of the key's
// fingerprint as described by RFC 4716 section 4.
func FingerprintLegacyMD5(pubKey PublicKey) string {

View File

@@ -240,7 +240,7 @@ func (m *mux) onePacket() error {
id := binary.BigEndian.Uint32(packet[1:])
ch := m.chanList.getChan(id)
if ch == nil {
return fmt.Errorf("ssh: invalid channel %d", id)
return m.handleUnknownChannelPacket(id, packet)
}
return ch.handlePacket(packet)
@@ -328,3 +328,24 @@ func (m *mux) openChannel(chanType string, extra []byte) (*channel, error) {
return nil, fmt.Errorf("ssh: unexpected packet in response to channel open: %T", msg)
}
}
func (m *mux) handleUnknownChannelPacket(id uint32, packet []byte) error {
msg, err := decode(packet)
if err != nil {
return err
}
switch msg := msg.(type) {
// RFC 4254 section 5.4 says unrecognized channel requests should
// receive a failure response.
case *channelRequestMsg:
if msg.WantReply {
return m.sendMessage(channelRequestFailureMsg{
PeersID: msg.PeersID,
})
}
return nil
default:
return fmt.Errorf("ssh: invalid channel %d", id)
}
}

View File

@@ -284,8 +284,8 @@ func (s *connection) serverHandshake(config *ServerConfig) (*Permissions, error)
func isAcceptableAlgo(algo string) bool {
switch algo {
case KeyAlgoRSA, KeyAlgoDSA, KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521, KeyAlgoED25519,
CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoED25519v01:
case KeyAlgoRSA, KeyAlgoDSA, KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521, KeyAlgoSKECDSA256, KeyAlgoED25519, KeyAlgoSKED25519,
CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoSKECDSA256v01, CertAlgoED25519v01, CertAlgoSKED25519v01:
return true
}
return false

View File

@@ -7,6 +7,7 @@ package terminal
import (
"bytes"
"io"
"runtime"
"strconv"
"sync"
"unicode/utf8"
@@ -112,6 +113,7 @@ func NewTerminal(c io.ReadWriter, prompt string) *Terminal {
}
const (
keyCtrlC = 3
keyCtrlD = 4
keyCtrlU = 21
keyEnter = '\r'
@@ -150,8 +152,12 @@ func bytesToKey(b []byte, pasteActive bool) (rune, []byte) {
switch b[0] {
case 1: // ^A
return keyHome, b[1:]
case 2: // ^B
return keyLeft, b[1:]
case 5: // ^E
return keyEnd, b[1:]
case 6: // ^F
return keyRight, b[1:]
case 8: // ^H
return keyBackspace, b[1:]
case 11: // ^K
@@ -737,6 +743,9 @@ func (t *Terminal) readLine() (line string, err error) {
return "", io.EOF
}
}
if key == keyCtrlC {
return "", io.EOF
}
if key == keyPasteStart {
t.pasteActive = true
if len(t.line) == 0 {
@@ -939,6 +948,8 @@ func (s *stRingBuffer) NthPreviousEntry(n int) (value string, ok bool) {
// readPasswordLine reads from reader until it finds \n or io.EOF.
// The slice returned does not include the \n.
// readPasswordLine also ignores any \r it finds.
// Windows uses \r as end of line. So, on Windows, readPasswordLine
// reads until it finds \r and ignores any \n it finds during processing.
func readPasswordLine(reader io.Reader) ([]byte, error) {
var buf [1]byte
var ret []byte
@@ -947,10 +958,20 @@ func readPasswordLine(reader io.Reader) ([]byte, error) {
n, err := reader.Read(buf[:])
if n > 0 {
switch buf[0] {
case '\b':
if len(ret) > 0 {
ret = ret[:len(ret)-1]
}
case '\n':
return ret, nil
if runtime.GOOS != "windows" {
return ret, nil
}
// otherwise ignore \n
case '\r':
// remove \r from passwords on Windows
if runtime.GOOS == "windows" {
return ret, nil
}
// otherwise ignore \r
default:
ret = append(ret, buf[0])
}

View File

@@ -85,8 +85,8 @@ func ReadPassword(fd int) ([]byte, error) {
}
old := st
st &^= (windows.ENABLE_ECHO_INPUT)
st |= (windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT | windows.ENABLE_PROCESSED_OUTPUT)
st &^= (windows.ENABLE_ECHO_INPUT | windows.ENABLE_LINE_INPUT)
st |= (windows.ENABLE_PROCESSED_OUTPUT | windows.ENABLE_PROCESSED_INPUT)
if err := windows.SetConsoleMode(windows.Handle(fd), st); err != nil {
return nil, err
}