4
0
mirror of https://github.com/cwinfo/matterbridge.git synced 2025-07-02 12:46:17 +00:00

Use mod vendor for vendored directory (backwards compatible)

This commit is contained in:
Wim
2018-08-06 21:47:05 +02:00
parent 4fb4b7aa6c
commit 51062863a5
1112 changed files with 15660 additions and 420183 deletions

View File

@ -1,27 +0,0 @@
Copyright (c) 2009 The Go Authors. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

View File

@ -1,683 +0,0 @@
// 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 agent implements the ssh-agent protocol, and provides both
// a client and a server. The client can talk to a standard ssh-agent
// that uses UNIX sockets, and one could implement an alternative
// ssh-agent process using the sample server.
//
// References:
// [PROTOCOL.agent]: http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL.agent?rev=HEAD
package agent // import "golang.org/x/crypto/ssh/agent"
import (
"bytes"
"crypto/dsa"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rsa"
"encoding/base64"
"encoding/binary"
"errors"
"fmt"
"io"
"math/big"
"sync"
"golang.org/x/crypto/ed25519"
"golang.org/x/crypto/ssh"
)
// Agent represents the capabilities of an ssh-agent.
type Agent interface {
// List returns the identities known to the agent.
List() ([]*Key, error)
// Sign has the agent sign the data using a protocol 2 key as defined
// in [PROTOCOL.agent] section 2.6.2.
Sign(key ssh.PublicKey, data []byte) (*ssh.Signature, error)
// Add adds a private key to the agent.
Add(key AddedKey) error
// Remove removes all identities with the given public key.
Remove(key ssh.PublicKey) error
// RemoveAll removes all identities.
RemoveAll() error
// Lock locks the agent. Sign and Remove will fail, and List will empty an empty list.
Lock(passphrase []byte) error
// Unlock undoes the effect of Lock
Unlock(passphrase []byte) error
// Signers returns signers for all the known keys.
Signers() ([]ssh.Signer, error)
}
// ConstraintExtension describes an optional constraint defined by users.
type ConstraintExtension struct {
// ExtensionName consist of a UTF-8 string suffixed by the
// implementation domain following the naming scheme defined
// in Section 4.2 of [RFC4251], e.g. "foo@example.com".
ExtensionName string
// ExtensionDetails contains the actual content of the extended
// constraint.
ExtensionDetails []byte
}
// AddedKey describes an SSH key to be added to an Agent.
type AddedKey struct {
// PrivateKey must be a *rsa.PrivateKey, *dsa.PrivateKey or
// *ecdsa.PrivateKey, which will be inserted into the agent.
PrivateKey interface{}
// Certificate, if not nil, is communicated to the agent and will be
// stored with the key.
Certificate *ssh.Certificate
// Comment is an optional, free-form string.
Comment string
// LifetimeSecs, if not zero, is the number of seconds that the
// agent will store the key for.
LifetimeSecs uint32
// ConfirmBeforeUse, if true, requests that the agent confirm with the
// user before each use of this key.
ConfirmBeforeUse bool
// ConstraintExtensions are the experimental or private-use constraints
// defined by users.
ConstraintExtensions []ConstraintExtension
}
// See [PROTOCOL.agent], section 3.
const (
agentRequestV1Identities = 1
agentRemoveAllV1Identities = 9
// 3.2 Requests from client to agent for protocol 2 key operations
agentAddIdentity = 17
agentRemoveIdentity = 18
agentRemoveAllIdentities = 19
agentAddIDConstrained = 25
// 3.3 Key-type independent requests from client to agent
agentAddSmartcardKey = 20
agentRemoveSmartcardKey = 21
agentLock = 22
agentUnlock = 23
agentAddSmartcardKeyConstrained = 26
// 3.7 Key constraint identifiers
agentConstrainLifetime = 1
agentConstrainConfirm = 2
agentConstrainExtension = 3
)
// maxAgentResponseBytes is the maximum agent reply size that is accepted. This
// is a sanity check, not a limit in the spec.
const maxAgentResponseBytes = 16 << 20
// Agent messages:
// These structures mirror the wire format of the corresponding ssh agent
// messages found in [PROTOCOL.agent].
// 3.4 Generic replies from agent to client
const agentFailure = 5
type failureAgentMsg struct{}
const agentSuccess = 6
type successAgentMsg struct{}
// See [PROTOCOL.agent], section 2.5.2.
const agentRequestIdentities = 11
type requestIdentitiesAgentMsg struct{}
// See [PROTOCOL.agent], section 2.5.2.
const agentIdentitiesAnswer = 12
type identitiesAnswerAgentMsg struct {
NumKeys uint32 `sshtype:"12"`
Keys []byte `ssh:"rest"`
}
// See [PROTOCOL.agent], section 2.6.2.
const agentSignRequest = 13
type signRequestAgentMsg struct {
KeyBlob []byte `sshtype:"13"`
Data []byte
Flags uint32
}
// See [PROTOCOL.agent], section 2.6.2.
// 3.6 Replies from agent to client for protocol 2 key operations
const agentSignResponse = 14
type signResponseAgentMsg struct {
SigBlob []byte `sshtype:"14"`
}
type publicKey struct {
Format string
Rest []byte `ssh:"rest"`
}
// 3.7 Key constraint identifiers
type constrainLifetimeAgentMsg struct {
LifetimeSecs uint32 `sshtype:"1"`
}
type constrainExtensionAgentMsg struct {
ExtensionName string `sshtype:"3"`
ExtensionDetails []byte
// Rest is a field used for parsing, not part of message
Rest []byte `ssh:"rest"`
}
// Key represents a protocol 2 public key as defined in
// [PROTOCOL.agent], section 2.5.2.
type Key struct {
Format string
Blob []byte
Comment string
}
func clientErr(err error) error {
return fmt.Errorf("agent: client error: %v", err)
}
// String returns the storage form of an agent key with the format, base64
// encoded serialized key, and the comment if it is not empty.
func (k *Key) String() string {
s := string(k.Format) + " " + base64.StdEncoding.EncodeToString(k.Blob)
if k.Comment != "" {
s += " " + k.Comment
}
return s
}
// Type returns the public key type.
func (k *Key) Type() string {
return k.Format
}
// Marshal returns key blob to satisfy the ssh.PublicKey interface.
func (k *Key) Marshal() []byte {
return k.Blob
}
// Verify satisfies the ssh.PublicKey interface.
func (k *Key) Verify(data []byte, sig *ssh.Signature) error {
pubKey, err := ssh.ParsePublicKey(k.Blob)
if err != nil {
return fmt.Errorf("agent: bad public key: %v", err)
}
return pubKey.Verify(data, sig)
}
type wireKey struct {
Format string
Rest []byte `ssh:"rest"`
}
func parseKey(in []byte) (out *Key, rest []byte, err error) {
var record struct {
Blob []byte
Comment string
Rest []byte `ssh:"rest"`
}
if err := ssh.Unmarshal(in, &record); err != nil {
return nil, nil, err
}
var wk wireKey
if err := ssh.Unmarshal(record.Blob, &wk); err != nil {
return nil, nil, err
}
return &Key{
Format: wk.Format,
Blob: record.Blob,
Comment: record.Comment,
}, record.Rest, nil
}
// client is a client for an ssh-agent process.
type client struct {
// conn is typically a *net.UnixConn
conn io.ReadWriter
// mu is used to prevent concurrent access to the agent
mu sync.Mutex
}
// NewClient returns an Agent that talks to an ssh-agent process over
// the given connection.
func NewClient(rw io.ReadWriter) Agent {
return &client{conn: rw}
}
// call sends an RPC to the agent. On success, the reply is
// unmarshaled into reply and replyType is set to the first byte of
// the reply, which contains the type of the message.
func (c *client) call(req []byte) (reply interface{}, err error) {
c.mu.Lock()
defer c.mu.Unlock()
msg := make([]byte, 4+len(req))
binary.BigEndian.PutUint32(msg, uint32(len(req)))
copy(msg[4:], req)
if _, err = c.conn.Write(msg); err != nil {
return nil, clientErr(err)
}
var respSizeBuf [4]byte
if _, err = io.ReadFull(c.conn, respSizeBuf[:]); err != nil {
return nil, clientErr(err)
}
respSize := binary.BigEndian.Uint32(respSizeBuf[:])
if respSize > maxAgentResponseBytes {
return nil, clientErr(err)
}
buf := make([]byte, respSize)
if _, err = io.ReadFull(c.conn, buf); err != nil {
return nil, clientErr(err)
}
reply, err = unmarshal(buf)
if err != nil {
return nil, clientErr(err)
}
return reply, err
}
func (c *client) simpleCall(req []byte) error {
resp, err := c.call(req)
if err != nil {
return err
}
if _, ok := resp.(*successAgentMsg); ok {
return nil
}
return errors.New("agent: failure")
}
func (c *client) RemoveAll() error {
return c.simpleCall([]byte{agentRemoveAllIdentities})
}
func (c *client) Remove(key ssh.PublicKey) error {
req := ssh.Marshal(&agentRemoveIdentityMsg{
KeyBlob: key.Marshal(),
})
return c.simpleCall(req)
}
func (c *client) Lock(passphrase []byte) error {
req := ssh.Marshal(&agentLockMsg{
Passphrase: passphrase,
})
return c.simpleCall(req)
}
func (c *client) Unlock(passphrase []byte) error {
req := ssh.Marshal(&agentUnlockMsg{
Passphrase: passphrase,
})
return c.simpleCall(req)
}
// List returns the identities known to the agent.
func (c *client) List() ([]*Key, error) {
// see [PROTOCOL.agent] section 2.5.2.
req := []byte{agentRequestIdentities}
msg, err := c.call(req)
if err != nil {
return nil, err
}
switch msg := msg.(type) {
case *identitiesAnswerAgentMsg:
if msg.NumKeys > maxAgentResponseBytes/8 {
return nil, errors.New("agent: too many keys in agent reply")
}
keys := make([]*Key, msg.NumKeys)
data := msg.Keys
for i := uint32(0); i < msg.NumKeys; i++ {
var key *Key
var err error
if key, data, err = parseKey(data); err != nil {
return nil, err
}
keys[i] = key
}
return keys, nil
case *failureAgentMsg:
return nil, errors.New("agent: failed to list keys")
}
panic("unreachable")
}
// Sign has the agent sign the data using a protocol 2 key as defined
// in [PROTOCOL.agent] section 2.6.2.
func (c *client) Sign(key ssh.PublicKey, data []byte) (*ssh.Signature, error) {
req := ssh.Marshal(signRequestAgentMsg{
KeyBlob: key.Marshal(),
Data: data,
})
msg, err := c.call(req)
if err != nil {
return nil, err
}
switch msg := msg.(type) {
case *signResponseAgentMsg:
var sig ssh.Signature
if err := ssh.Unmarshal(msg.SigBlob, &sig); err != nil {
return nil, err
}
return &sig, nil
case *failureAgentMsg:
return nil, errors.New("agent: failed to sign challenge")
}
panic("unreachable")
}
// unmarshal parses an agent message in packet, returning the parsed
// form and the message type of packet.
func unmarshal(packet []byte) (interface{}, error) {
if len(packet) < 1 {
return nil, errors.New("agent: empty packet")
}
var msg interface{}
switch packet[0] {
case agentFailure:
return new(failureAgentMsg), nil
case agentSuccess:
return new(successAgentMsg), nil
case agentIdentitiesAnswer:
msg = new(identitiesAnswerAgentMsg)
case agentSignResponse:
msg = new(signResponseAgentMsg)
case agentV1IdentitiesAnswer:
msg = new(agentV1IdentityMsg)
default:
return nil, fmt.Errorf("agent: unknown type tag %d", packet[0])
}
if err := ssh.Unmarshal(packet, msg); err != nil {
return nil, err
}
return msg, nil
}
type rsaKeyMsg struct {
Type string `sshtype:"17|25"`
N *big.Int
E *big.Int
D *big.Int
Iqmp *big.Int // IQMP = Inverse Q Mod P
P *big.Int
Q *big.Int
Comments string
Constraints []byte `ssh:"rest"`
}
type dsaKeyMsg struct {
Type string `sshtype:"17|25"`
P *big.Int
Q *big.Int
G *big.Int
Y *big.Int
X *big.Int
Comments string
Constraints []byte `ssh:"rest"`
}
type ecdsaKeyMsg struct {
Type string `sshtype:"17|25"`
Curve string
KeyBytes []byte
D *big.Int
Comments string
Constraints []byte `ssh:"rest"`
}
type ed25519KeyMsg struct {
Type string `sshtype:"17|25"`
Pub []byte
Priv []byte
Comments string
Constraints []byte `ssh:"rest"`
}
// Insert adds a private key to the agent.
func (c *client) insertKey(s interface{}, comment string, constraints []byte) error {
var req []byte
switch k := s.(type) {
case *rsa.PrivateKey:
if len(k.Primes) != 2 {
return fmt.Errorf("agent: unsupported RSA key with %d primes", len(k.Primes))
}
k.Precompute()
req = ssh.Marshal(rsaKeyMsg{
Type: ssh.KeyAlgoRSA,
N: k.N,
E: big.NewInt(int64(k.E)),
D: k.D,
Iqmp: k.Precomputed.Qinv,
P: k.Primes[0],
Q: k.Primes[1],
Comments: comment,
Constraints: constraints,
})
case *dsa.PrivateKey:
req = ssh.Marshal(dsaKeyMsg{
Type: ssh.KeyAlgoDSA,
P: k.P,
Q: k.Q,
G: k.G,
Y: k.Y,
X: k.X,
Comments: comment,
Constraints: constraints,
})
case *ecdsa.PrivateKey:
nistID := fmt.Sprintf("nistp%d", k.Params().BitSize)
req = ssh.Marshal(ecdsaKeyMsg{
Type: "ecdsa-sha2-" + nistID,
Curve: nistID,
KeyBytes: elliptic.Marshal(k.Curve, k.X, k.Y),
D: k.D,
Comments: comment,
Constraints: constraints,
})
case *ed25519.PrivateKey:
req = ssh.Marshal(ed25519KeyMsg{
Type: ssh.KeyAlgoED25519,
Pub: []byte(*k)[32:],
Priv: []byte(*k),
Comments: comment,
Constraints: constraints,
})
default:
return fmt.Errorf("agent: unsupported key type %T", s)
}
// if constraints are present then the message type needs to be changed.
if len(constraints) != 0 {
req[0] = agentAddIDConstrained
}
resp, err := c.call(req)
if err != nil {
return err
}
if _, ok := resp.(*successAgentMsg); ok {
return nil
}
return errors.New("agent: failure")
}
type rsaCertMsg struct {
Type string `sshtype:"17|25"`
CertBytes []byte
D *big.Int
Iqmp *big.Int // IQMP = Inverse Q Mod P
P *big.Int
Q *big.Int
Comments string
Constraints []byte `ssh:"rest"`
}
type dsaCertMsg struct {
Type string `sshtype:"17|25"`
CertBytes []byte
X *big.Int
Comments string
Constraints []byte `ssh:"rest"`
}
type ecdsaCertMsg struct {
Type string `sshtype:"17|25"`
CertBytes []byte
D *big.Int
Comments string
Constraints []byte `ssh:"rest"`
}
type ed25519CertMsg struct {
Type string `sshtype:"17|25"`
CertBytes []byte
Pub []byte
Priv []byte
Comments string
Constraints []byte `ssh:"rest"`
}
// Add adds a private key to the agent. If a certificate is given,
// that certificate is added instead as public key.
func (c *client) Add(key AddedKey) error {
var constraints []byte
if secs := key.LifetimeSecs; secs != 0 {
constraints = append(constraints, ssh.Marshal(constrainLifetimeAgentMsg{secs})...)
}
if key.ConfirmBeforeUse {
constraints = append(constraints, agentConstrainConfirm)
}
cert := key.Certificate
if cert == nil {
return c.insertKey(key.PrivateKey, key.Comment, constraints)
}
return c.insertCert(key.PrivateKey, cert, key.Comment, constraints)
}
func (c *client) insertCert(s interface{}, cert *ssh.Certificate, comment string, constraints []byte) error {
var req []byte
switch k := s.(type) {
case *rsa.PrivateKey:
if len(k.Primes) != 2 {
return fmt.Errorf("agent: unsupported RSA key with %d primes", len(k.Primes))
}
k.Precompute()
req = ssh.Marshal(rsaCertMsg{
Type: cert.Type(),
CertBytes: cert.Marshal(),
D: k.D,
Iqmp: k.Precomputed.Qinv,
P: k.Primes[0],
Q: k.Primes[1],
Comments: comment,
Constraints: constraints,
})
case *dsa.PrivateKey:
req = ssh.Marshal(dsaCertMsg{
Type: cert.Type(),
CertBytes: cert.Marshal(),
X: k.X,
Comments: comment,
Constraints: constraints,
})
case *ecdsa.PrivateKey:
req = ssh.Marshal(ecdsaCertMsg{
Type: cert.Type(),
CertBytes: cert.Marshal(),
D: k.D,
Comments: comment,
Constraints: constraints,
})
case *ed25519.PrivateKey:
req = ssh.Marshal(ed25519CertMsg{
Type: cert.Type(),
CertBytes: cert.Marshal(),
Pub: []byte(*k)[32:],
Priv: []byte(*k),
Comments: comment,
Constraints: constraints,
})
default:
return fmt.Errorf("agent: unsupported key type %T", s)
}
// if constraints are present then the message type needs to be changed.
if len(constraints) != 0 {
req[0] = agentAddIDConstrained
}
signer, err := ssh.NewSignerFromKey(s)
if err != nil {
return err
}
if bytes.Compare(cert.Key.Marshal(), signer.PublicKey().Marshal()) != 0 {
return errors.New("agent: signer and cert have different public key")
}
resp, err := c.call(req)
if err != nil {
return err
}
if _, ok := resp.(*successAgentMsg); ok {
return nil
}
return errors.New("agent: failure")
}
// Signers provides a callback for client authentication.
func (c *client) Signers() ([]ssh.Signer, error) {
keys, err := c.List()
if err != nil {
return nil, err
}
var result []ssh.Signer
for _, k := range keys {
result = append(result, &agentKeyringSigner{c, k})
}
return result, nil
}
type agentKeyringSigner struct {
agent *client
pub ssh.PublicKey
}
func (s *agentKeyringSigner) PublicKey() ssh.PublicKey {
return s.pub
}
func (s *agentKeyringSigner) Sign(rand io.Reader, data []byte) (*ssh.Signature, error) {
// The agent has its own entropy source, so the rand argument is ignored.
return s.agent.Sign(s.pub, data)
}

View File

@ -1,103 +0,0 @@
// 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 agent
import (
"errors"
"io"
"net"
"sync"
"golang.org/x/crypto/ssh"
)
// RequestAgentForwarding sets up agent forwarding for the session.
// ForwardToAgent or ForwardToRemote should be called to route
// the authentication requests.
func RequestAgentForwarding(session *ssh.Session) error {
ok, err := session.SendRequest("auth-agent-req@openssh.com", true, nil)
if err != nil {
return err
}
if !ok {
return errors.New("forwarding request denied")
}
return nil
}
// ForwardToAgent routes authentication requests to the given keyring.
func ForwardToAgent(client *ssh.Client, keyring Agent) error {
channels := client.HandleChannelOpen(channelType)
if channels == nil {
return errors.New("agent: already have handler for " + channelType)
}
go func() {
for ch := range channels {
channel, reqs, err := ch.Accept()
if err != nil {
continue
}
go ssh.DiscardRequests(reqs)
go func() {
ServeAgent(keyring, channel)
channel.Close()
}()
}
}()
return nil
}
const channelType = "auth-agent@openssh.com"
// ForwardToRemote routes authentication requests to the ssh-agent
// process serving on the given unix socket.
func ForwardToRemote(client *ssh.Client, addr string) error {
channels := client.HandleChannelOpen(channelType)
if channels == nil {
return errors.New("agent: already have handler for " + channelType)
}
conn, err := net.Dial("unix", addr)
if err != nil {
return err
}
conn.Close()
go func() {
for ch := range channels {
channel, reqs, err := ch.Accept()
if err != nil {
continue
}
go ssh.DiscardRequests(reqs)
go forwardUnixSocket(channel, addr)
}
}()
return nil
}
func forwardUnixSocket(channel ssh.Channel, addr string) {
conn, err := net.Dial("unix", addr)
if err != nil {
return
}
var wg sync.WaitGroup
wg.Add(2)
go func() {
io.Copy(conn, channel)
conn.(*net.UnixConn).CloseWrite()
wg.Done()
}()
go func() {
io.Copy(channel, conn)
channel.CloseWrite()
wg.Done()
}()
wg.Wait()
conn.Close()
channel.Close()
}

View File

@ -1,215 +0,0 @@
// 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 agent
import (
"bytes"
"crypto/rand"
"crypto/subtle"
"errors"
"fmt"
"sync"
"time"
"golang.org/x/crypto/ssh"
)
type privKey struct {
signer ssh.Signer
comment string
expire *time.Time
}
type keyring struct {
mu sync.Mutex
keys []privKey
locked bool
passphrase []byte
}
var errLocked = errors.New("agent: locked")
// NewKeyring returns an Agent that holds keys in memory. It is safe
// for concurrent use by multiple goroutines.
func NewKeyring() Agent {
return &keyring{}
}
// RemoveAll removes all identities.
func (r *keyring) RemoveAll() error {
r.mu.Lock()
defer r.mu.Unlock()
if r.locked {
return errLocked
}
r.keys = nil
return nil
}
// removeLocked does the actual key removal. The caller must already be holding the
// keyring mutex.
func (r *keyring) removeLocked(want []byte) error {
found := false
for i := 0; i < len(r.keys); {
if bytes.Equal(r.keys[i].signer.PublicKey().Marshal(), want) {
found = true
r.keys[i] = r.keys[len(r.keys)-1]
r.keys = r.keys[:len(r.keys)-1]
continue
} else {
i++
}
}
if !found {
return errors.New("agent: key not found")
}
return nil
}
// Remove removes all identities with the given public key.
func (r *keyring) Remove(key ssh.PublicKey) error {
r.mu.Lock()
defer r.mu.Unlock()
if r.locked {
return errLocked
}
return r.removeLocked(key.Marshal())
}
// Lock locks the agent. Sign and Remove will fail, and List will return an empty list.
func (r *keyring) Lock(passphrase []byte) error {
r.mu.Lock()
defer r.mu.Unlock()
if r.locked {
return errLocked
}
r.locked = true
r.passphrase = passphrase
return nil
}
// Unlock undoes the effect of Lock
func (r *keyring) Unlock(passphrase []byte) error {
r.mu.Lock()
defer r.mu.Unlock()
if !r.locked {
return errors.New("agent: not locked")
}
if len(passphrase) != len(r.passphrase) || 1 != subtle.ConstantTimeCompare(passphrase, r.passphrase) {
return fmt.Errorf("agent: incorrect passphrase")
}
r.locked = false
r.passphrase = nil
return nil
}
// expireKeysLocked removes expired keys from the keyring. If a key was added
// with a lifetimesecs contraint and seconds >= lifetimesecs seconds have
// ellapsed, it is removed. The caller *must* be holding the keyring mutex.
func (r *keyring) expireKeysLocked() {
for _, k := range r.keys {
if k.expire != nil && time.Now().After(*k.expire) {
r.removeLocked(k.signer.PublicKey().Marshal())
}
}
}
// List returns the identities known to the agent.
func (r *keyring) List() ([]*Key, error) {
r.mu.Lock()
defer r.mu.Unlock()
if r.locked {
// section 2.7: locked agents return empty.
return nil, nil
}
r.expireKeysLocked()
var ids []*Key
for _, k := range r.keys {
pub := k.signer.PublicKey()
ids = append(ids, &Key{
Format: pub.Type(),
Blob: pub.Marshal(),
Comment: k.comment})
}
return ids, nil
}
// Insert adds a private key to the keyring. If a certificate
// is given, that certificate is added as public key. Note that
// any constraints given are ignored.
func (r *keyring) Add(key AddedKey) error {
r.mu.Lock()
defer r.mu.Unlock()
if r.locked {
return errLocked
}
signer, err := ssh.NewSignerFromKey(key.PrivateKey)
if err != nil {
return err
}
if cert := key.Certificate; cert != nil {
signer, err = ssh.NewCertSigner(cert, signer)
if err != nil {
return err
}
}
p := privKey{
signer: signer,
comment: key.Comment,
}
if key.LifetimeSecs > 0 {
t := time.Now().Add(time.Duration(key.LifetimeSecs) * time.Second)
p.expire = &t
}
r.keys = append(r.keys, p)
return nil
}
// Sign returns a signature for the data.
func (r *keyring) Sign(key ssh.PublicKey, data []byte) (*ssh.Signature, error) {
r.mu.Lock()
defer r.mu.Unlock()
if r.locked {
return nil, errLocked
}
r.expireKeysLocked()
wanted := key.Marshal()
for _, k := range r.keys {
if bytes.Equal(k.signer.PublicKey().Marshal(), wanted) {
return k.signer.Sign(rand.Reader, data)
}
}
return nil, errors.New("not found")
}
// Signers returns signers for all the known keys.
func (r *keyring) Signers() ([]ssh.Signer, error) {
r.mu.Lock()
defer r.mu.Unlock()
if r.locked {
return nil, errLocked
}
r.expireKeysLocked()
s := make([]ssh.Signer, 0, len(r.keys))
for _, k := range r.keys {
s = append(s, k.signer)
}
return s, nil
}

View File

@ -1,523 +0,0 @@
// 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 agent
import (
"crypto/dsa"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rsa"
"encoding/binary"
"errors"
"fmt"
"io"
"log"
"math/big"
"golang.org/x/crypto/ed25519"
"golang.org/x/crypto/ssh"
)
// Server wraps an Agent and uses it to implement the agent side of
// the SSH-agent, wire protocol.
type server struct {
agent Agent
}
func (s *server) processRequestBytes(reqData []byte) []byte {
rep, err := s.processRequest(reqData)
if err != nil {
if err != errLocked {
// TODO(hanwen): provide better logging interface?
log.Printf("agent %d: %v", reqData[0], err)
}
return []byte{agentFailure}
}
if err == nil && rep == nil {
return []byte{agentSuccess}
}
return ssh.Marshal(rep)
}
func marshalKey(k *Key) []byte {
var record struct {
Blob []byte
Comment string
}
record.Blob = k.Marshal()
record.Comment = k.Comment
return ssh.Marshal(&record)
}
// See [PROTOCOL.agent], section 2.5.1.
const agentV1IdentitiesAnswer = 2
type agentV1IdentityMsg struct {
Numkeys uint32 `sshtype:"2"`
}
type agentRemoveIdentityMsg struct {
KeyBlob []byte `sshtype:"18"`
}
type agentLockMsg struct {
Passphrase []byte `sshtype:"22"`
}
type agentUnlockMsg struct {
Passphrase []byte `sshtype:"23"`
}
func (s *server) processRequest(data []byte) (interface{}, error) {
switch data[0] {
case agentRequestV1Identities:
return &agentV1IdentityMsg{0}, nil
case agentRemoveAllV1Identities:
return nil, nil
case agentRemoveIdentity:
var req agentRemoveIdentityMsg
if err := ssh.Unmarshal(data, &req); err != nil {
return nil, err
}
var wk wireKey
if err := ssh.Unmarshal(req.KeyBlob, &wk); err != nil {
return nil, err
}
return nil, s.agent.Remove(&Key{Format: wk.Format, Blob: req.KeyBlob})
case agentRemoveAllIdentities:
return nil, s.agent.RemoveAll()
case agentLock:
var req agentLockMsg
if err := ssh.Unmarshal(data, &req); err != nil {
return nil, err
}
return nil, s.agent.Lock(req.Passphrase)
case agentUnlock:
var req agentUnlockMsg
if err := ssh.Unmarshal(data, &req); err != nil {
return nil, err
}
return nil, s.agent.Unlock(req.Passphrase)
case agentSignRequest:
var req signRequestAgentMsg
if err := ssh.Unmarshal(data, &req); err != nil {
return nil, err
}
var wk wireKey
if err := ssh.Unmarshal(req.KeyBlob, &wk); err != nil {
return nil, err
}
k := &Key{
Format: wk.Format,
Blob: req.KeyBlob,
}
sig, err := s.agent.Sign(k, req.Data) // TODO(hanwen): flags.
if err != nil {
return nil, err
}
return &signResponseAgentMsg{SigBlob: ssh.Marshal(sig)}, nil
case agentRequestIdentities:
keys, err := s.agent.List()
if err != nil {
return nil, err
}
rep := identitiesAnswerAgentMsg{
NumKeys: uint32(len(keys)),
}
for _, k := range keys {
rep.Keys = append(rep.Keys, marshalKey(k)...)
}
return rep, nil
case agentAddIDConstrained, agentAddIdentity:
return nil, s.insertIdentity(data)
}
return nil, fmt.Errorf("unknown opcode %d", data[0])
}
func parseConstraints(constraints []byte) (lifetimeSecs uint32, confirmBeforeUse bool, extensions []ConstraintExtension, err error) {
for len(constraints) != 0 {
switch constraints[0] {
case agentConstrainLifetime:
lifetimeSecs = binary.BigEndian.Uint32(constraints[1:5])
constraints = constraints[5:]
case agentConstrainConfirm:
confirmBeforeUse = true
constraints = constraints[1:]
case agentConstrainExtension:
var msg constrainExtensionAgentMsg
if err = ssh.Unmarshal(constraints, &msg); err != nil {
return 0, false, nil, err
}
extensions = append(extensions, ConstraintExtension{
ExtensionName: msg.ExtensionName,
ExtensionDetails: msg.ExtensionDetails,
})
constraints = msg.Rest
default:
return 0, false, nil, fmt.Errorf("unknown constraint type: %d", constraints[0])
}
}
return
}
func setConstraints(key *AddedKey, constraintBytes []byte) error {
lifetimeSecs, confirmBeforeUse, constraintExtensions, err := parseConstraints(constraintBytes)
if err != nil {
return err
}
key.LifetimeSecs = lifetimeSecs
key.ConfirmBeforeUse = confirmBeforeUse
key.ConstraintExtensions = constraintExtensions
return nil
}
func parseRSAKey(req []byte) (*AddedKey, error) {
var k rsaKeyMsg
if err := ssh.Unmarshal(req, &k); err != nil {
return nil, err
}
if k.E.BitLen() > 30 {
return nil, errors.New("agent: RSA public exponent too large")
}
priv := &rsa.PrivateKey{
PublicKey: rsa.PublicKey{
E: int(k.E.Int64()),
N: k.N,
},
D: k.D,
Primes: []*big.Int{k.P, k.Q},
}
priv.Precompute()
addedKey := &AddedKey{PrivateKey: priv, Comment: k.Comments}
if err := setConstraints(addedKey, k.Constraints); err != nil {
return nil, err
}
return addedKey, nil
}
func parseEd25519Key(req []byte) (*AddedKey, error) {
var k ed25519KeyMsg
if err := ssh.Unmarshal(req, &k); err != nil {
return nil, err
}
priv := ed25519.PrivateKey(k.Priv)
addedKey := &AddedKey{PrivateKey: &priv, Comment: k.Comments}
if err := setConstraints(addedKey, k.Constraints); err != nil {
return nil, err
}
return addedKey, nil
}
func parseDSAKey(req []byte) (*AddedKey, error) {
var k dsaKeyMsg
if err := ssh.Unmarshal(req, &k); err != nil {
return nil, err
}
priv := &dsa.PrivateKey{
PublicKey: dsa.PublicKey{
Parameters: dsa.Parameters{
P: k.P,
Q: k.Q,
G: k.G,
},
Y: k.Y,
},
X: k.X,
}
addedKey := &AddedKey{PrivateKey: priv, Comment: k.Comments}
if err := setConstraints(addedKey, k.Constraints); err != nil {
return nil, err
}
return addedKey, nil
}
func unmarshalECDSA(curveName string, keyBytes []byte, privScalar *big.Int) (priv *ecdsa.PrivateKey, err error) {
priv = &ecdsa.PrivateKey{
D: privScalar,
}
switch curveName {
case "nistp256":
priv.Curve = elliptic.P256()
case "nistp384":
priv.Curve = elliptic.P384()
case "nistp521":
priv.Curve = elliptic.P521()
default:
return nil, fmt.Errorf("agent: unknown curve %q", curveName)
}
priv.X, priv.Y = elliptic.Unmarshal(priv.Curve, keyBytes)
if priv.X == nil || priv.Y == nil {
return nil, errors.New("agent: point not on curve")
}
return priv, nil
}
func parseEd25519Cert(req []byte) (*AddedKey, error) {
var k ed25519CertMsg
if err := ssh.Unmarshal(req, &k); err != nil {
return nil, err
}
pubKey, err := ssh.ParsePublicKey(k.CertBytes)
if err != nil {
return nil, err
}
priv := ed25519.PrivateKey(k.Priv)
cert, ok := pubKey.(*ssh.Certificate)
if !ok {
return nil, errors.New("agent: bad ED25519 certificate")
}
addedKey := &AddedKey{PrivateKey: &priv, Certificate: cert, Comment: k.Comments}
if err := setConstraints(addedKey, k.Constraints); err != nil {
return nil, err
}
return addedKey, nil
}
func parseECDSAKey(req []byte) (*AddedKey, error) {
var k ecdsaKeyMsg
if err := ssh.Unmarshal(req, &k); err != nil {
return nil, err
}
priv, err := unmarshalECDSA(k.Curve, k.KeyBytes, k.D)
if err != nil {
return nil, err
}
addedKey := &AddedKey{PrivateKey: priv, Comment: k.Comments}
if err := setConstraints(addedKey, k.Constraints); err != nil {
return nil, err
}
return addedKey, nil
}
func parseRSACert(req []byte) (*AddedKey, error) {
var k rsaCertMsg
if err := ssh.Unmarshal(req, &k); err != nil {
return nil, err
}
pubKey, err := ssh.ParsePublicKey(k.CertBytes)
if err != nil {
return nil, err
}
cert, ok := pubKey.(*ssh.Certificate)
if !ok {
return nil, errors.New("agent: bad RSA certificate")
}
// An RSA publickey as marshaled by rsaPublicKey.Marshal() in keys.go
var rsaPub struct {
Name string
E *big.Int
N *big.Int
}
if err := ssh.Unmarshal(cert.Key.Marshal(), &rsaPub); err != nil {
return nil, fmt.Errorf("agent: Unmarshal failed to parse public key: %v", err)
}
if rsaPub.E.BitLen() > 30 {
return nil, errors.New("agent: RSA public exponent too large")
}
priv := rsa.PrivateKey{
PublicKey: rsa.PublicKey{
E: int(rsaPub.E.Int64()),
N: rsaPub.N,
},
D: k.D,
Primes: []*big.Int{k.Q, k.P},
}
priv.Precompute()
addedKey := &AddedKey{PrivateKey: &priv, Certificate: cert, Comment: k.Comments}
if err := setConstraints(addedKey, k.Constraints); err != nil {
return nil, err
}
return addedKey, nil
}
func parseDSACert(req []byte) (*AddedKey, error) {
var k dsaCertMsg
if err := ssh.Unmarshal(req, &k); err != nil {
return nil, err
}
pubKey, err := ssh.ParsePublicKey(k.CertBytes)
if err != nil {
return nil, err
}
cert, ok := pubKey.(*ssh.Certificate)
if !ok {
return nil, errors.New("agent: bad DSA certificate")
}
// A DSA publickey as marshaled by dsaPublicKey.Marshal() in keys.go
var w struct {
Name string
P, Q, G, Y *big.Int
}
if err := ssh.Unmarshal(cert.Key.Marshal(), &w); err != nil {
return nil, fmt.Errorf("agent: Unmarshal failed to parse public key: %v", err)
}
priv := &dsa.PrivateKey{
PublicKey: dsa.PublicKey{
Parameters: dsa.Parameters{
P: w.P,
Q: w.Q,
G: w.G,
},
Y: w.Y,
},
X: k.X,
}
addedKey := &AddedKey{PrivateKey: priv, Certificate: cert, Comment: k.Comments}
if err := setConstraints(addedKey, k.Constraints); err != nil {
return nil, err
}
return addedKey, nil
}
func parseECDSACert(req []byte) (*AddedKey, error) {
var k ecdsaCertMsg
if err := ssh.Unmarshal(req, &k); err != nil {
return nil, err
}
pubKey, err := ssh.ParsePublicKey(k.CertBytes)
if err != nil {
return nil, err
}
cert, ok := pubKey.(*ssh.Certificate)
if !ok {
return nil, errors.New("agent: bad ECDSA certificate")
}
// An ECDSA publickey as marshaled by ecdsaPublicKey.Marshal() in keys.go
var ecdsaPub struct {
Name string
ID string
Key []byte
}
if err := ssh.Unmarshal(cert.Key.Marshal(), &ecdsaPub); err != nil {
return nil, err
}
priv, err := unmarshalECDSA(ecdsaPub.ID, ecdsaPub.Key, k.D)
if err != nil {
return nil, err
}
addedKey := &AddedKey{PrivateKey: priv, Certificate: cert, Comment: k.Comments}
if err := setConstraints(addedKey, k.Constraints); err != nil {
return nil, err
}
return addedKey, nil
}
func (s *server) insertIdentity(req []byte) error {
var record struct {
Type string `sshtype:"17|25"`
Rest []byte `ssh:"rest"`
}
if err := ssh.Unmarshal(req, &record); err != nil {
return err
}
var addedKey *AddedKey
var err error
switch record.Type {
case ssh.KeyAlgoRSA:
addedKey, err = parseRSAKey(req)
case ssh.KeyAlgoDSA:
addedKey, err = parseDSAKey(req)
case ssh.KeyAlgoECDSA256, ssh.KeyAlgoECDSA384, ssh.KeyAlgoECDSA521:
addedKey, err = parseECDSAKey(req)
case ssh.KeyAlgoED25519:
addedKey, err = parseEd25519Key(req)
case ssh.CertAlgoRSAv01:
addedKey, err = parseRSACert(req)
case ssh.CertAlgoDSAv01:
addedKey, err = parseDSACert(req)
case ssh.CertAlgoECDSA256v01, ssh.CertAlgoECDSA384v01, ssh.CertAlgoECDSA521v01:
addedKey, err = parseECDSACert(req)
case ssh.CertAlgoED25519v01:
addedKey, err = parseEd25519Cert(req)
default:
return fmt.Errorf("agent: not implemented: %q", record.Type)
}
if err != nil {
return err
}
return s.agent.Add(*addedKey)
}
// ServeAgent serves the agent protocol on the given connection. It
// returns when an I/O error occurs.
func ServeAgent(agent Agent, c io.ReadWriter) error {
s := &server{agent}
var length [4]byte
for {
if _, err := io.ReadFull(c, length[:]); err != nil {
return err
}
l := binary.BigEndian.Uint32(length[:])
if l > maxAgentResponseBytes {
// We also cap requests.
return fmt.Errorf("agent: request too large: %d", l)
}
req := make([]byte, l)
if _, err := io.ReadFull(c, req); err != nil {
return err
}
repData := s.processRequestBytes(req)
if len(repData) > maxAgentResponseBytes {
return fmt.Errorf("agent: reply too large: %d bytes", len(repData))
}
binary.BigEndian.PutUint32(length[:], uint32(len(repData)))
if _, err := c.Write(length[:]); err != nil {
return err
}
if _, err := c.Write(repData); err != nil {
return err
}
}
}

View File

@ -44,7 +44,9 @@ type Signature struct {
const CertTimeInfinity = 1<<64 - 1
// An Certificate represents an OpenSSH certificate as defined in
// [PROTOCOL.certkeys]?rev=1.8.
// [PROTOCOL.certkeys]?rev=1.8. The Certificate type implements the
// PublicKey interface, so it can be unmarshaled using
// ParsePublicKey.
type Certificate struct {
Nonce []byte
Key PublicKey
@ -340,7 +342,7 @@ func (c *CertChecker) Authenticate(conn ConnMetadata, pubKey PublicKey) (*Permis
// the signature of the certificate.
func (c *CertChecker) CheckCert(principal string, cert *Certificate) error {
if c.IsRevoked != nil && c.IsRevoked(cert) {
return fmt.Errorf("ssh: certicate serial %d revoked", cert.Serial)
return fmt.Errorf("ssh: certificate serial %d revoked", cert.Serial)
}
for opt := range cert.CriticalOptions {

View File

@ -16,6 +16,9 @@ import (
"hash"
"io"
"io/ioutil"
"golang.org/x/crypto/internal/chacha20"
"golang.org/x/crypto/poly1305"
)
const (
@ -53,78 +56,78 @@ func newRC4(key, iv []byte) (cipher.Stream, error) {
return rc4.NewCipher(key)
}
type streamCipherMode struct {
keySize int
ivSize int
skip int
createFunc func(key, iv []byte) (cipher.Stream, error)
type cipherMode struct {
keySize int
ivSize int
create func(key, iv []byte, macKey []byte, algs directionAlgorithms) (packetCipher, error)
}
func (c *streamCipherMode) createStream(key, iv []byte) (cipher.Stream, error) {
if len(key) < c.keySize {
panic("ssh: key length too small for cipher")
}
if len(iv) < c.ivSize {
panic("ssh: iv too small for cipher")
}
stream, err := c.createFunc(key[:c.keySize], iv[:c.ivSize])
if err != nil {
return nil, err
}
var streamDump []byte
if c.skip > 0 {
streamDump = make([]byte, 512)
}
for remainingToDump := c.skip; remainingToDump > 0; {
dumpThisTime := remainingToDump
if dumpThisTime > len(streamDump) {
dumpThisTime = len(streamDump)
func streamCipherMode(skip int, createFunc func(key, iv []byte) (cipher.Stream, error)) func(key, iv []byte, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
return func(key, iv, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
stream, err := createFunc(key, iv)
if err != nil {
return nil, err
}
stream.XORKeyStream(streamDump[:dumpThisTime], streamDump[:dumpThisTime])
remainingToDump -= dumpThisTime
}
return stream, nil
var streamDump []byte
if skip > 0 {
streamDump = make([]byte, 512)
}
for remainingToDump := skip; remainingToDump > 0; {
dumpThisTime := remainingToDump
if dumpThisTime > len(streamDump) {
dumpThisTime = len(streamDump)
}
stream.XORKeyStream(streamDump[:dumpThisTime], streamDump[:dumpThisTime])
remainingToDump -= dumpThisTime
}
mac := macModes[algs.MAC].new(macKey)
return &streamPacketCipher{
mac: mac,
etm: macModes[algs.MAC].etm,
macResult: make([]byte, mac.Size()),
cipher: stream,
}, nil
}
}
// cipherModes documents properties of supported ciphers. Ciphers not included
// are not supported and will not be negotiated, even if explicitly requested in
// ClientConfig.Crypto.Ciphers.
var cipherModes = map[string]*streamCipherMode{
var cipherModes = map[string]*cipherMode{
// Ciphers from RFC4344, which introduced many CTR-based ciphers. Algorithms
// are defined in the order specified in the RFC.
"aes128-ctr": {16, aes.BlockSize, 0, newAESCTR},
"aes192-ctr": {24, aes.BlockSize, 0, newAESCTR},
"aes256-ctr": {32, aes.BlockSize, 0, newAESCTR},
"aes128-ctr": {16, aes.BlockSize, streamCipherMode(0, newAESCTR)},
"aes192-ctr": {24, aes.BlockSize, streamCipherMode(0, newAESCTR)},
"aes256-ctr": {32, aes.BlockSize, streamCipherMode(0, newAESCTR)},
// Ciphers from RFC4345, which introduces security-improved arcfour ciphers.
// They are defined in the order specified in the RFC.
"arcfour128": {16, 0, 1536, newRC4},
"arcfour256": {32, 0, 1536, newRC4},
"arcfour128": {16, 0, streamCipherMode(1536, newRC4)},
"arcfour256": {32, 0, streamCipherMode(1536, newRC4)},
// Cipher defined in RFC 4253, which describes SSH Transport Layer Protocol.
// Note that this cipher is not safe, as stated in RFC 4253: "Arcfour (and
// RC4) has problems with weak keys, and should be used with caution."
// RFC4345 introduces improved versions of Arcfour.
"arcfour": {16, 0, 0, newRC4},
"arcfour": {16, 0, streamCipherMode(0, newRC4)},
// AES-GCM is not a stream cipher, so it is constructed with a
// special case. If we add any more non-stream ciphers, we
// should invest a cleaner way to do this.
gcmCipherID: {16, 12, 0, nil},
// AEAD ciphers
gcmCipherID: {16, 12, newGCMCipher},
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
// 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.
aes128cbcID: {16, aes.BlockSize, 0, nil},
aes128cbcID: {16, aes.BlockSize, newAESCBCCipher},
// 3des-cbc is insecure and is disabled by default.
tripledescbcID: {24, des.BlockSize, 0, nil},
// 3des-cbc is insecure and is not included in the default
// config.
tripledescbcID: {24, des.BlockSize, newTripleDESCBCCipher},
}
// prefixLen is the length of the packet prefix that contains the packet length
@ -304,7 +307,7 @@ type gcmCipher struct {
buf []byte
}
func newGCMCipher(iv, key []byte) (packetCipher, error) {
func newGCMCipher(key, iv, unusedMacKey []byte, unusedAlgs directionAlgorithms) (packetCipher, error) {
c, err := aes.NewCipher(key)
if err != nil {
return nil, err
@ -422,7 +425,7 @@ type cbcCipher struct {
oracleCamouflage uint32
}
func newCBCCipher(c cipher.Block, iv, key, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
func newCBCCipher(c cipher.Block, key, iv, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
cbc := &cbcCipher{
mac: macModes[algs.MAC].new(macKey),
decrypter: cipher.NewCBCDecrypter(c, iv),
@ -436,13 +439,13 @@ func newCBCCipher(c cipher.Block, iv, key, macKey []byte, algs directionAlgorith
return cbc, nil
}
func newAESCBCCipher(iv, key, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
func newAESCBCCipher(key, iv, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
c, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
cbc, err := newCBCCipher(c, iv, key, macKey, algs)
cbc, err := newCBCCipher(c, key, iv, macKey, algs)
if err != nil {
return nil, err
}
@ -450,13 +453,13 @@ func newAESCBCCipher(iv, key, macKey []byte, algs directionAlgorithms) (packetCi
return cbc, nil
}
func newTripleDESCBCCipher(iv, key, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
func newTripleDESCBCCipher(key, iv, macKey []byte, algs directionAlgorithms) (packetCipher, error) {
c, err := des.NewTripleDESCipher(key)
if err != nil {
return nil, err
}
cbc, err := newCBCCipher(c, iv, key, macKey, algs)
cbc, err := newCBCCipher(c, key, iv, macKey, algs)
if err != nil {
return nil, err
}
@ -627,3 +630,142 @@ func (c *cbcCipher) writePacket(seqNum uint32, w io.Writer, rand io.Reader, pack
return nil
}
const chacha20Poly1305ID = "chacha20-poly1305@openssh.com"
// chacha20Poly1305Cipher implements the chacha20-poly1305@openssh.com
// AEAD, which is described here:
//
// https://tools.ietf.org/html/draft-josefsson-ssh-chacha20-poly1305-openssh-00
//
// the methods here also implement padding, which RFC4253 Section 6
// also requires of stream ciphers.
type chacha20Poly1305Cipher struct {
lengthKey [32]byte
contentKey [32]byte
buf []byte
}
func newChaCha20Cipher(key, unusedIV, unusedMACKey []byte, unusedAlgs directionAlgorithms) (packetCipher, error) {
if len(key) != 64 {
panic(len(key))
}
c := &chacha20Poly1305Cipher{
buf: make([]byte, 256),
}
copy(c.contentKey[:], key[:32])
copy(c.lengthKey[:], key[32:])
return c, nil
}
// The Poly1305 key is obtained by encrypting 32 0-bytes.
var chacha20PolyKeyInput [32]byte
func (c *chacha20Poly1305Cipher) readPacket(seqNum uint32, r io.Reader) ([]byte, error) {
var counter [16]byte
binary.BigEndian.PutUint64(counter[8:], uint64(seqNum))
var polyKey [32]byte
chacha20.XORKeyStream(polyKey[:], chacha20PolyKeyInput[:], &counter, &c.contentKey)
encryptedLength := c.buf[:4]
if _, err := io.ReadFull(r, encryptedLength); err != nil {
return nil, err
}
var lenBytes [4]byte
chacha20.XORKeyStream(lenBytes[:], encryptedLength, &counter, &c.lengthKey)
length := binary.BigEndian.Uint32(lenBytes[:])
if length > maxPacket {
return nil, errors.New("ssh: invalid packet length, packet too large")
}
contentEnd := 4 + length
packetEnd := contentEnd + poly1305.TagSize
if uint32(cap(c.buf)) < packetEnd {
c.buf = make([]byte, packetEnd)
copy(c.buf[:], encryptedLength)
} else {
c.buf = c.buf[:packetEnd]
}
if _, err := io.ReadFull(r, c.buf[4:packetEnd]); err != nil {
return nil, err
}
var mac [poly1305.TagSize]byte
copy(mac[:], c.buf[contentEnd:packetEnd])
if !poly1305.Verify(&mac, c.buf[:contentEnd], &polyKey) {
return nil, errors.New("ssh: MAC failure")
}
counter[0] = 1
plain := c.buf[4:contentEnd]
chacha20.XORKeyStream(plain, plain, &counter, &c.contentKey)
padding := plain[0]
if padding < 4 {
// padding is a byte, so it automatically satisfies
// the maximum size, which is 255.
return nil, fmt.Errorf("ssh: illegal padding %d", padding)
}
if int(padding)+1 >= len(plain) {
return nil, fmt.Errorf("ssh: padding %d too large", padding)
}
plain = plain[1 : len(plain)-int(padding)]
return plain, nil
}
func (c *chacha20Poly1305Cipher) writePacket(seqNum uint32, w io.Writer, rand io.Reader, payload []byte) error {
var counter [16]byte
binary.BigEndian.PutUint64(counter[8:], uint64(seqNum))
var polyKey [32]byte
chacha20.XORKeyStream(polyKey[:], chacha20PolyKeyInput[:], &counter, &c.contentKey)
// There is no blocksize, so fall back to multiple of 8 byte
// padding, as described in RFC 4253, Sec 6.
const packetSizeMultiple = 8
padding := packetSizeMultiple - (1+len(payload))%packetSizeMultiple
if padding < 4 {
padding += packetSizeMultiple
}
// size (4 bytes), padding (1), payload, padding, tag.
totalLength := 4 + 1 + len(payload) + padding + poly1305.TagSize
if cap(c.buf) < totalLength {
c.buf = make([]byte, totalLength)
} else {
c.buf = c.buf[:totalLength]
}
binary.BigEndian.PutUint32(c.buf, uint32(1+len(payload)+padding))
chacha20.XORKeyStream(c.buf, c.buf[:4], &counter, &c.lengthKey)
c.buf[4] = byte(padding)
copy(c.buf[5:], payload)
packetEnd := 5 + len(payload) + padding
if _, err := io.ReadFull(rand, c.buf[5+len(payload):packetEnd]); err != nil {
return err
}
counter[0] = 1
chacha20.XORKeyStream(c.buf[4:], c.buf[4:packetEnd], &counter, &c.contentKey)
var mac [poly1305.TagSize]byte
poly1305.Sum(&mac, c.buf[:packetEnd], &polyKey)
copy(c.buf[packetEnd:], mac[:])
if _, err := w.Write(c.buf); err != nil {
return err
}
return nil
}

View File

@ -11,6 +11,14 @@ import (
"io"
)
type authResult int
const (
authFailure authResult = iota
authPartialSuccess
authSuccess
)
// clientAuthenticate authenticates with the remote server. See RFC 4252.
func (c *connection) clientAuthenticate(config *ClientConfig) error {
// initiate user auth session
@ -37,11 +45,12 @@ func (c *connection) clientAuthenticate(config *ClientConfig) error {
if err != nil {
return err
}
if ok {
if ok == authSuccess {
// success
return nil
} else if ok == authFailure {
tried[auth.method()] = true
}
tried[auth.method()] = true
if methods == nil {
methods = lastMethods
}
@ -82,7 +91,7 @@ type AuthMethod interface {
// If authentication is not successful, a []string of alternative
// method names is returned. If the slice is nil, it will be ignored
// and the previous set of possible methods will be reused.
auth(session []byte, user string, p packetConn, rand io.Reader) (bool, []string, error)
auth(session []byte, user string, p packetConn, rand io.Reader) (authResult, []string, error)
// method returns the RFC 4252 method name.
method() string
@ -91,13 +100,13 @@ type AuthMethod interface {
// "none" authentication, RFC 4252 section 5.2.
type noneAuth int
func (n *noneAuth) auth(session []byte, user string, c packetConn, rand io.Reader) (bool, []string, error) {
func (n *noneAuth) auth(session []byte, user string, c packetConn, rand io.Reader) (authResult, []string, error) {
if err := c.writePacket(Marshal(&userAuthRequestMsg{
User: user,
Service: serviceSSH,
Method: "none",
})); err != nil {
return false, nil, err
return authFailure, nil, err
}
return handleAuthResponse(c)
@ -111,7 +120,7 @@ func (n *noneAuth) method() string {
// a function call, e.g. by prompting the user.
type passwordCallback func() (password string, err error)
func (cb passwordCallback) auth(session []byte, user string, c packetConn, rand io.Reader) (bool, []string, error) {
func (cb passwordCallback) auth(session []byte, user string, c packetConn, rand io.Reader) (authResult, []string, error) {
type passwordAuthMsg struct {
User string `sshtype:"50"`
Service string
@ -125,7 +134,7 @@ func (cb passwordCallback) auth(session []byte, user string, c packetConn, rand
// The program may only find out that the user doesn't have a password
// when prompting.
if err != nil {
return false, nil, err
return authFailure, nil, err
}
if err := c.writePacket(Marshal(&passwordAuthMsg{
@ -135,7 +144,7 @@ func (cb passwordCallback) auth(session []byte, user string, c packetConn, rand
Reply: false,
Password: pw,
})); err != nil {
return false, nil, err
return authFailure, nil, err
}
return handleAuthResponse(c)
@ -178,7 +187,7 @@ func (cb publicKeyCallback) method() string {
return "publickey"
}
func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand io.Reader) (bool, []string, error) {
func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand io.Reader) (authResult, []string, error) {
// Authentication is performed by sending an enquiry to test if a key is
// acceptable to the remote. If the key is acceptable, the client will
// attempt to authenticate with the valid key. If not the client will repeat
@ -186,13 +195,13 @@ func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand
signers, err := cb()
if err != nil {
return false, nil, err
return authFailure, nil, err
}
var methods []string
for _, signer := range signers {
ok, err := validateKey(signer.PublicKey(), user, c)
if err != nil {
return false, nil, err
return authFailure, nil, err
}
if !ok {
continue
@ -206,7 +215,7 @@ func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand
Method: cb.method(),
}, []byte(pub.Type()), pubKey))
if err != nil {
return false, nil, err
return authFailure, nil, err
}
// manually wrap the serialized signature in a string
@ -224,24 +233,24 @@ func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand
}
p := Marshal(&msg)
if err := c.writePacket(p); err != nil {
return false, nil, err
return authFailure, nil, err
}
var success bool
var success authResult
success, methods, err = handleAuthResponse(c)
if err != nil {
return false, nil, err
return authFailure, nil, err
}
// If authentication succeeds or the list of available methods does not
// contain the "publickey" method, do not attempt to authenticate with any
// other keys. According to RFC 4252 Section 7, the latter can occur when
// additional authentication methods are required.
if success || !containsMethod(methods, cb.method()) {
if success == authSuccess || !containsMethod(methods, cb.method()) {
return success, methods, err
}
}
return false, methods, nil
return authFailure, methods, nil
}
func containsMethod(methods []string, method string) bool {
@ -318,28 +327,31 @@ func PublicKeysCallback(getSigners func() (signers []Signer, err error)) AuthMet
// handleAuthResponse returns whether the preceding authentication request succeeded
// along with a list of remaining authentication methods to try next and
// an error if an unexpected response was received.
func handleAuthResponse(c packetConn) (bool, []string, error) {
func handleAuthResponse(c packetConn) (authResult, []string, error) {
for {
packet, err := c.readPacket()
if err != nil {
return false, nil, err
return authFailure, nil, err
}
switch packet[0] {
case msgUserAuthBanner:
if err := handleBannerResponse(c, packet); err != nil {
return false, nil, err
return authFailure, nil, err
}
case msgUserAuthFailure:
var msg userAuthFailureMsg
if err := Unmarshal(packet, &msg); err != nil {
return false, nil, err
return authFailure, nil, err
}
return false, msg.Methods, nil
if msg.PartialSuccess {
return authPartialSuccess, msg.Methods, nil
}
return authFailure, msg.Methods, nil
case msgUserAuthSuccess:
return true, nil, nil
return authSuccess, nil, nil
default:
return false, nil, unexpectedMessageError(msgUserAuthSuccess, packet[0])
return authFailure, nil, unexpectedMessageError(msgUserAuthSuccess, packet[0])
}
}
}
@ -381,7 +393,7 @@ func (cb KeyboardInteractiveChallenge) method() string {
return "keyboard-interactive"
}
func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packetConn, rand io.Reader) (bool, []string, error) {
func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packetConn, rand io.Reader) (authResult, []string, error) {
type initiateMsg struct {
User string `sshtype:"50"`
Service string
@ -395,20 +407,20 @@ func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packe
Service: serviceSSH,
Method: "keyboard-interactive",
})); err != nil {
return false, nil, err
return authFailure, nil, err
}
for {
packet, err := c.readPacket()
if err != nil {
return false, nil, err
return authFailure, nil, err
}
// like handleAuthResponse, but with less options.
switch packet[0] {
case msgUserAuthBanner:
if err := handleBannerResponse(c, packet); err != nil {
return false, nil, err
return authFailure, nil, err
}
continue
case msgUserAuthInfoRequest:
@ -416,18 +428,21 @@ func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packe
case msgUserAuthFailure:
var msg userAuthFailureMsg
if err := Unmarshal(packet, &msg); err != nil {
return false, nil, err
return authFailure, nil, err
}
return false, msg.Methods, nil
if msg.PartialSuccess {
return authPartialSuccess, msg.Methods, nil
}
return authFailure, msg.Methods, nil
case msgUserAuthSuccess:
return true, nil, nil
return authSuccess, nil, nil
default:
return false, nil, unexpectedMessageError(msgUserAuthInfoRequest, packet[0])
return authFailure, nil, unexpectedMessageError(msgUserAuthInfoRequest, packet[0])
}
var msg userAuthInfoRequestMsg
if err := Unmarshal(packet, &msg); err != nil {
return false, nil, err
return authFailure, nil, err
}
// Manually unpack the prompt/echo pairs.
@ -437,7 +452,7 @@ func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packe
for i := 0; i < int(msg.NumPrompts); i++ {
prompt, r, ok := parseString(rest)
if !ok || len(r) == 0 {
return false, nil, errors.New("ssh: prompt format error")
return authFailure, nil, errors.New("ssh: prompt format error")
}
prompts = append(prompts, string(prompt))
echos = append(echos, r[0] != 0)
@ -445,16 +460,16 @@ func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packe
}
if len(rest) != 0 {
return false, nil, errors.New("ssh: extra data following keyboard-interactive pairs")
return authFailure, nil, errors.New("ssh: extra data following keyboard-interactive pairs")
}
answers, err := cb(msg.User, msg.Instruction, prompts, echos)
if err != nil {
return false, nil, err
return authFailure, nil, err
}
if len(answers) != len(prompts) {
return false, nil, errors.New("ssh: not enough answers from keyboard-interactive callback")
return authFailure, nil, errors.New("ssh: not enough answers from keyboard-interactive callback")
}
responseLength := 1 + 4
for _, a := range answers {
@ -470,7 +485,7 @@ func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packe
}
if err := c.writePacket(serialized); err != nil {
return false, nil, err
return authFailure, nil, err
}
}
}
@ -480,10 +495,10 @@ type retryableAuthMethod struct {
maxTries int
}
func (r *retryableAuthMethod) auth(session []byte, user string, c packetConn, rand io.Reader) (ok bool, methods []string, err error) {
func (r *retryableAuthMethod) auth(session []byte, user string, c packetConn, rand io.Reader) (ok authResult, methods []string, err error) {
for i := 0; r.maxTries <= 0 || i < r.maxTries; i++ {
ok, methods, err = r.authMethod.auth(session, user, c, rand)
if ok || err != nil { // either success or error terminate
if ok != authFailure || err != nil { // either success, partial success or error terminate
return ok, methods, err
}
}

View File

@ -24,11 +24,21 @@ const (
serviceSSH = "ssh-connection"
)
// supportedCiphers specifies the supported ciphers in preference order.
// supportedCiphers lists ciphers we support but might not recommend.
var supportedCiphers = []string{
"aes128-ctr", "aes192-ctr", "aes256-ctr",
"aes128-gcm@openssh.com",
"arcfour256", "arcfour128",
chacha20Poly1305ID,
"arcfour256", "arcfour128", "arcfour",
aes128cbcID,
tripledescbcID,
}
// preferredCiphers specifies the default preference for ciphers.
var preferredCiphers = []string{
"aes128-gcm@openssh.com",
chacha20Poly1305ID,
"aes128-ctr", "aes192-ctr", "aes256-ctr",
}
// supportedKexAlgos specifies the supported key-exchange algorithms in
@ -211,7 +221,7 @@ func (c *Config) SetDefaults() {
c.Rand = rand.Reader
}
if c.Ciphers == nil {
c.Ciphers = supportedCiphers
c.Ciphers = preferredCiphers
}
var ciphers []string
for _, c := range c.Ciphers {

View File

@ -276,7 +276,8 @@ type PublicKey interface {
Type() string
// Marshal returns the serialized key data in SSH wire format,
// with the name prefix.
// with the name prefix. To unmarshal the returned data, use
// the ParsePublicKey function.
Marshal() []byte
// Verify that sig is a signature on the given data using this

View File

@ -1,546 +0,0 @@
// Copyright 2017 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 knownhosts implements a parser for the OpenSSH
// known_hosts host key database.
package knownhosts
import (
"bufio"
"bytes"
"crypto/hmac"
"crypto/rand"
"crypto/sha1"
"encoding/base64"
"errors"
"fmt"
"io"
"net"
"os"
"strings"
"golang.org/x/crypto/ssh"
)
// See the sshd manpage
// (http://man.openbsd.org/sshd#SSH_KNOWN_HOSTS_FILE_FORMAT) for
// background.
type addr struct{ host, port string }
func (a *addr) String() string {
h := a.host
if strings.Contains(h, ":") {
h = "[" + h + "]"
}
return h + ":" + a.port
}
type matcher interface {
match([]addr) bool
}
type hostPattern struct {
negate bool
addr addr
}
func (p *hostPattern) String() string {
n := ""
if p.negate {
n = "!"
}
return n + p.addr.String()
}
type hostPatterns []hostPattern
func (ps hostPatterns) match(addrs []addr) bool {
matched := false
for _, p := range ps {
for _, a := range addrs {
m := p.match(a)
if !m {
continue
}
if p.negate {
return false
}
matched = true
}
}
return matched
}
// See
// https://android.googlesource.com/platform/external/openssh/+/ab28f5495c85297e7a597c1ba62e996416da7c7e/addrmatch.c
// The matching of * has no regard for separators, unlike filesystem globs
func wildcardMatch(pat []byte, str []byte) bool {
for {
if len(pat) == 0 {
return len(str) == 0
}
if len(str) == 0 {
return false
}
if pat[0] == '*' {
if len(pat) == 1 {
return true
}
for j := range str {
if wildcardMatch(pat[1:], str[j:]) {
return true
}
}
return false
}
if pat[0] == '?' || pat[0] == str[0] {
pat = pat[1:]
str = str[1:]
} else {
return false
}
}
}
func (p *hostPattern) match(a addr) bool {
return wildcardMatch([]byte(p.addr.host), []byte(a.host)) && p.addr.port == a.port
}
type keyDBLine struct {
cert bool
matcher matcher
knownKey KnownKey
}
func serialize(k ssh.PublicKey) string {
return k.Type() + " " + base64.StdEncoding.EncodeToString(k.Marshal())
}
func (l *keyDBLine) match(addrs []addr) bool {
return l.matcher.match(addrs)
}
type hostKeyDB struct {
// Serialized version of revoked keys
revoked map[string]*KnownKey
lines []keyDBLine
}
func newHostKeyDB() *hostKeyDB {
db := &hostKeyDB{
revoked: make(map[string]*KnownKey),
}
return db
}
func keyEq(a, b ssh.PublicKey) bool {
return bytes.Equal(a.Marshal(), b.Marshal())
}
// IsAuthorityForHost can be used as a callback in ssh.CertChecker
func (db *hostKeyDB) IsHostAuthority(remote ssh.PublicKey, address string) bool {
h, p, err := net.SplitHostPort(address)
if err != nil {
return false
}
a := addr{host: h, port: p}
for _, l := range db.lines {
if l.cert && keyEq(l.knownKey.Key, remote) && l.match([]addr{a}) {
return true
}
}
return false
}
// IsRevoked can be used as a callback in ssh.CertChecker
func (db *hostKeyDB) IsRevoked(key *ssh.Certificate) bool {
_, ok := db.revoked[string(key.Marshal())]
return ok
}
const markerCert = "@cert-authority"
const markerRevoked = "@revoked"
func nextWord(line []byte) (string, []byte) {
i := bytes.IndexAny(line, "\t ")
if i == -1 {
return string(line), nil
}
return string(line[:i]), bytes.TrimSpace(line[i:])
}
func parseLine(line []byte) (marker, host string, key ssh.PublicKey, err error) {
if w, next := nextWord(line); w == markerCert || w == markerRevoked {
marker = w
line = next
}
host, line = nextWord(line)
if len(line) == 0 {
return "", "", nil, errors.New("knownhosts: missing host pattern")
}
// ignore the keytype as it's in the key blob anyway.
_, line = nextWord(line)
if len(line) == 0 {
return "", "", nil, errors.New("knownhosts: missing key type pattern")
}
keyBlob, _ := nextWord(line)
keyBytes, err := base64.StdEncoding.DecodeString(keyBlob)
if err != nil {
return "", "", nil, err
}
key, err = ssh.ParsePublicKey(keyBytes)
if err != nil {
return "", "", nil, err
}
return marker, host, key, nil
}
func (db *hostKeyDB) parseLine(line []byte, filename string, linenum int) error {
marker, pattern, key, err := parseLine(line)
if err != nil {
return err
}
if marker == markerRevoked {
db.revoked[string(key.Marshal())] = &KnownKey{
Key: key,
Filename: filename,
Line: linenum,
}
return nil
}
entry := keyDBLine{
cert: marker == markerCert,
knownKey: KnownKey{
Filename: filename,
Line: linenum,
Key: key,
},
}
if pattern[0] == '|' {
entry.matcher, err = newHashedHost(pattern)
} else {
entry.matcher, err = newHostnameMatcher(pattern)
}
if err != nil {
return err
}
db.lines = append(db.lines, entry)
return nil
}
func newHostnameMatcher(pattern string) (matcher, error) {
var hps hostPatterns
for _, p := range strings.Split(pattern, ",") {
if len(p) == 0 {
continue
}
var a addr
var negate bool
if p[0] == '!' {
negate = true
p = p[1:]
}
if len(p) == 0 {
return nil, errors.New("knownhosts: negation without following hostname")
}
var err error
if p[0] == '[' {
a.host, a.port, err = net.SplitHostPort(p)
if err != nil {
return nil, err
}
} else {
a.host, a.port, err = net.SplitHostPort(p)
if err != nil {
a.host = p
a.port = "22"
}
}
hps = append(hps, hostPattern{
negate: negate,
addr: a,
})
}
return hps, nil
}
// KnownKey represents a key declared in a known_hosts file.
type KnownKey struct {
Key ssh.PublicKey
Filename string
Line int
}
func (k *KnownKey) String() string {
return fmt.Sprintf("%s:%d: %s", k.Filename, k.Line, serialize(k.Key))
}
// KeyError is returned if we did not find the key in the host key
// database, or there was a mismatch. Typically, in batch
// applications, this should be interpreted as failure. Interactive
// applications can offer an interactive prompt to the user.
type KeyError struct {
// Want holds the accepted host keys. For each key algorithm,
// there can be one hostkey. If Want is empty, the host is
// unknown. If Want is non-empty, there was a mismatch, which
// can signify a MITM attack.
Want []KnownKey
}
func (u *KeyError) Error() string {
if len(u.Want) == 0 {
return "knownhosts: key is unknown"
}
return "knownhosts: key mismatch"
}
// RevokedError is returned if we found a key that was revoked.
type RevokedError struct {
Revoked KnownKey
}
func (r *RevokedError) Error() string {
return "knownhosts: key is revoked"
}
// check checks a key against the host database. This should not be
// used for verifying certificates.
func (db *hostKeyDB) check(address string, remote net.Addr, remoteKey ssh.PublicKey) error {
if revoked := db.revoked[string(remoteKey.Marshal())]; revoked != nil {
return &RevokedError{Revoked: *revoked}
}
host, port, err := net.SplitHostPort(remote.String())
if err != nil {
return fmt.Errorf("knownhosts: SplitHostPort(%s): %v", remote, err)
}
addrs := []addr{
{host, port},
}
if address != "" {
host, port, err := net.SplitHostPort(address)
if err != nil {
return fmt.Errorf("knownhosts: SplitHostPort(%s): %v", address, err)
}
addrs = append(addrs, addr{host, port})
}
return db.checkAddrs(addrs, remoteKey)
}
// checkAddrs checks if we can find the given public key for any of
// the given addresses. If we only find an entry for the IP address,
// or only the hostname, then this still succeeds.
func (db *hostKeyDB) checkAddrs(addrs []addr, remoteKey ssh.PublicKey) error {
// TODO(hanwen): are these the right semantics? What if there
// is just a key for the IP address, but not for the
// hostname?
// Algorithm => key.
knownKeys := map[string]KnownKey{}
for _, l := range db.lines {
if l.match(addrs) {
typ := l.knownKey.Key.Type()
if _, ok := knownKeys[typ]; !ok {
knownKeys[typ] = l.knownKey
}
}
}
keyErr := &KeyError{}
for _, v := range knownKeys {
keyErr.Want = append(keyErr.Want, v)
}
// Unknown remote host.
if len(knownKeys) == 0 {
return keyErr
}
// If the remote host starts using a different, unknown key type, we
// also interpret that as a mismatch.
if known, ok := knownKeys[remoteKey.Type()]; !ok || !keyEq(known.Key, remoteKey) {
return keyErr
}
return nil
}
// The Read function parses file contents.
func (db *hostKeyDB) Read(r io.Reader, filename string) error {
scanner := bufio.NewScanner(r)
lineNum := 0
for scanner.Scan() {
lineNum++
line := scanner.Bytes()
line = bytes.TrimSpace(line)
if len(line) == 0 || line[0] == '#' {
continue
}
if err := db.parseLine(line, filename, lineNum); err != nil {
return fmt.Errorf("knownhosts: %s:%d: %v", filename, lineNum, err)
}
}
return scanner.Err()
}
// New creates a host key callback from the given OpenSSH host key
// files. The returned callback is for use in
// ssh.ClientConfig.HostKeyCallback. Hashed hostnames are not supported.
func New(files ...string) (ssh.HostKeyCallback, error) {
db := newHostKeyDB()
for _, fn := range files {
f, err := os.Open(fn)
if err != nil {
return nil, err
}
defer f.Close()
if err := db.Read(f, fn); err != nil {
return nil, err
}
}
var certChecker ssh.CertChecker
certChecker.IsHostAuthority = db.IsHostAuthority
certChecker.IsRevoked = db.IsRevoked
certChecker.HostKeyFallback = db.check
return certChecker.CheckHostKey, nil
}
// Normalize normalizes an address into the form used in known_hosts
func Normalize(address string) string {
host, port, err := net.SplitHostPort(address)
if err != nil {
host = address
port = "22"
}
entry := host
if port != "22" {
entry = "[" + entry + "]:" + port
} else if strings.Contains(host, ":") && !strings.HasPrefix(host, "[") {
entry = "[" + entry + "]"
}
return entry
}
// Line returns a line to add append to the known_hosts files.
func Line(addresses []string, key ssh.PublicKey) string {
var trimmed []string
for _, a := range addresses {
trimmed = append(trimmed, Normalize(a))
}
return strings.Join(trimmed, ",") + " " + serialize(key)
}
// HashHostname hashes the given hostname. The hostname is not
// normalized before hashing.
func HashHostname(hostname string) string {
// TODO(hanwen): check if we can safely normalize this always.
salt := make([]byte, sha1.Size)
_, err := rand.Read(salt)
if err != nil {
panic(fmt.Sprintf("crypto/rand failure %v", err))
}
hash := hashHost(hostname, salt)
return encodeHash(sha1HashType, salt, hash)
}
func decodeHash(encoded string) (hashType string, salt, hash []byte, err error) {
if len(encoded) == 0 || encoded[0] != '|' {
err = errors.New("knownhosts: hashed host must start with '|'")
return
}
components := strings.Split(encoded, "|")
if len(components) != 4 {
err = fmt.Errorf("knownhosts: got %d components, want 3", len(components))
return
}
hashType = components[1]
if salt, err = base64.StdEncoding.DecodeString(components[2]); err != nil {
return
}
if hash, err = base64.StdEncoding.DecodeString(components[3]); err != nil {
return
}
return
}
func encodeHash(typ string, salt []byte, hash []byte) string {
return strings.Join([]string{"",
typ,
base64.StdEncoding.EncodeToString(salt),
base64.StdEncoding.EncodeToString(hash),
}, "|")
}
// See https://android.googlesource.com/platform/external/openssh/+/ab28f5495c85297e7a597c1ba62e996416da7c7e/hostfile.c#120
func hashHost(hostname string, salt []byte) []byte {
mac := hmac.New(sha1.New, salt)
mac.Write([]byte(hostname))
return mac.Sum(nil)
}
type hashedHost struct {
salt []byte
hash []byte
}
const sha1HashType = "1"
func newHashedHost(encoded string) (*hashedHost, error) {
typ, salt, hash, err := decodeHash(encoded)
if err != nil {
return nil, err
}
// The type field seems for future algorithm agility, but it's
// actually hardcoded in openssh currently, see
// https://android.googlesource.com/platform/external/openssh/+/ab28f5495c85297e7a597c1ba62e996416da7c7e/hostfile.c#120
if typ != sha1HashType {
return nil, fmt.Errorf("knownhosts: got hash type %s, must be '1'", typ)
}
return &hashedHost{salt: salt, hash: hash}, nil
}
func (h *hashedHost) match(addrs []addr) bool {
for _, a := range addrs {
if bytes.Equal(hashHost(Normalize(a.String()), h.salt), h.hash) {
return true
}
}
return false
}

View File

@ -166,6 +166,9 @@ type ServerConn struct {
// unsuccessful, it closes the connection and returns an error. The
// Request and NewChannel channels must be serviced, or the connection
// will hang.
//
// The returned error may be of type *ServerAuthError for
// authentication errors.
func NewServerConn(c net.Conn, config *ServerConfig) (*ServerConn, <-chan NewChannel, <-chan *Request, error) {
fullConf := *config
fullConf.SetDefaults()
@ -256,7 +259,7 @@ 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:
CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoED25519v01:
return true
}
return false
@ -292,12 +295,13 @@ func checkSourceAddress(addr net.Addr, sourceAddrs string) error {
return fmt.Errorf("ssh: remote address %v is not allowed because of source-address restriction", addr)
}
// ServerAuthError implements the error interface. It appends any authentication
// errors that may occur, and is returned if all of the authentication methods
// provided by the user failed to authenticate.
// ServerAuthError represents server authentication errors and is
// sometimes returned by NewServerConn. It appends any authentication
// errors that may occur, and is returned if all of the authentication
// methods provided by the user failed to authenticate.
type ServerAuthError struct {
// Errors contains authentication errors returned by the authentication
// callback methods.
// callback methods. The first entry is typically ErrNoAuth.
Errors []error
}
@ -309,6 +313,13 @@ func (l ServerAuthError) Error() string {
return "[" + strings.Join(errs, ", ") + "]"
}
// ErrNoAuth is the error value returned if no
// authentication method has been passed yet. This happens as a normal
// part of the authentication loop, since the client first tries
// 'none' authentication to discover available methods.
// It is returned in ServerAuthError.Errors from NewServerConn.
var ErrNoAuth = errors.New("ssh: no auth passed yet")
func (s *connection) serverAuthenticate(config *ServerConfig) (*Permissions, error) {
sessionID := s.transport.getSessionID()
var cache pubKeyCache
@ -363,7 +374,7 @@ userAuthLoop:
}
perms = nil
authErr := errors.New("no auth passed yet")
authErr := ErrNoAuth
switch userAuthReq.Method {
case "none":

View File

@ -93,5 +93,13 @@ func ReadPassword(fd int) ([]byte, error) {
windows.SetConsoleMode(windows.Handle(fd), old)
}()
return readPasswordLine(os.NewFile(uintptr(fd), "stdin"))
var h windows.Handle
p, _ := windows.GetCurrentProcess()
if err := windows.DuplicateHandle(p, windows.Handle(fd), p, &h, 0, false, windows.DUPLICATE_SAME_ACCESS); err != nil {
return nil, err
}
f := os.NewFile(uintptr(h), "stdin")
defer f.Close()
return readPasswordLine(f)
}

View File

@ -1,7 +0,0 @@
// 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 test contains integration tests for the
// golang.org/x/crypto/ssh package.
package test // import "golang.org/x/crypto/ssh/test"

View File

@ -6,6 +6,7 @@ package ssh
import (
"bufio"
"bytes"
"errors"
"io"
"log"
@ -232,52 +233,22 @@ var (
clientKeys = direction{[]byte{'A'}, []byte{'C'}, []byte{'E'}}
)
// generateKeys generates key material for IV, MAC and encryption.
func generateKeys(d direction, algs directionAlgorithms, kex *kexResult) (iv, key, macKey []byte) {
cipherMode := cipherModes[algs.Cipher]
macMode := macModes[algs.MAC]
iv = make([]byte, cipherMode.ivSize)
key = make([]byte, cipherMode.keySize)
macKey = make([]byte, macMode.keySize)
generateKeyMaterial(iv, d.ivTag, kex)
generateKeyMaterial(key, d.keyTag, kex)
generateKeyMaterial(macKey, d.macKeyTag, kex)
return
}
// setupKeys sets the cipher and MAC keys from kex.K, kex.H and sessionId, as
// described in RFC 4253, section 6.4. direction should either be serverKeys
// (to setup server->client keys) or clientKeys (for client->server keys).
func newPacketCipher(d direction, algs directionAlgorithms, kex *kexResult) (packetCipher, error) {
iv, key, macKey := generateKeys(d, algs, kex)
cipherMode := cipherModes[algs.Cipher]
macMode := macModes[algs.MAC]
if algs.Cipher == gcmCipherID {
return newGCMCipher(iv, key)
}
iv := make([]byte, cipherMode.ivSize)
key := make([]byte, cipherMode.keySize)
macKey := make([]byte, macMode.keySize)
if algs.Cipher == aes128cbcID {
return newAESCBCCipher(iv, key, macKey, algs)
}
generateKeyMaterial(iv, d.ivTag, kex)
generateKeyMaterial(key, d.keyTag, kex)
generateKeyMaterial(macKey, d.macKeyTag, kex)
if algs.Cipher == tripledescbcID {
return newTripleDESCBCCipher(iv, key, macKey, algs)
}
c := &streamPacketCipher{
mac: macModes[algs.MAC].new(macKey),
etm: macModes[algs.MAC].etm,
}
c.macResult = make([]byte, c.mac.Size())
var err error
c.cipher, err = cipherModes[algs.Cipher].createStream(key, iv)
if err != nil {
return nil, err
}
return c, nil
return cipherModes[algs.Cipher].create(key, iv, macKey, algs)
}
// generateKeyMaterial fills out with key material generated from tag, K, H
@ -342,7 +313,7 @@ func readVersion(r io.Reader) ([]byte, error) {
var ok bool
var buf [1]byte
for len(versionString) < maxVersionStringBytes {
for length := 0; length < maxVersionStringBytes; length++ {
_, err := io.ReadFull(r, buf[:])
if err != nil {
return nil, err
@ -350,6 +321,13 @@ func readVersion(r io.Reader) ([]byte, error) {
// The RFC says that the version should be terminated with \r\n
// but several SSH servers actually only send a \n.
if buf[0] == '\n' {
if !bytes.HasPrefix(versionString, []byte("SSH-")) {
// RFC 4253 says we need to ignore all version string lines
// except the one containing the SSH version (provided that
// all the lines do not exceed 255 bytes in total).
versionString = versionString[:0]
continue
}
ok = true
break
}