// 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
}
want := key.Marshal()
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
}
func (k KnownHosts) HostKeyCallback(hostname string, remote net.Addr, key ssh.PublicKey) error {
var addr *net.TCPAddr
if v, ok := remote.(*net.TCPAddr); ok {
addr = v
} else {
return UnsupportedAddrType
}
keyBytes := key.Marshal()
var matched []*Host
for _, l := range k {
if l.CertAuthority {
continue
}
if key.Type() != l.PublicKey.Type() {
continue
}
lKeyBytes := l.PublicKey.Marshal()
for _, h := range l.Hosts {
if h.Match(hostname, addr) {
if !bytes.Equal(keyBytes, lKeyBytes) {
return HostKeyMismatchError
}
if l.Revoked {
return HostRevokedError
}
matched = append(matched, h)
}
}
}
if len(matched) == 0 {
return HostNotFoundError
}
return nil
}
func (k *storedHostKey) Check(addr string, remote net.Addr, key ssh.PublicKey) error {
k.checkCount++
algo := key.Type()
if k.keys == nil || bytes.Compare(key.Marshal(), k.keys[algo]) != 0 {
return fmt.Errorf("host key mismatch. Got %q, want %q", key, k.keys[algo])
}
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
}
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")
}
func testAgentInterface(t *testing.T, agent Agent, key interface{}, cert *ssh.Certificate) {
signer, err := ssh.NewSignerFromKey(key)
if err != nil {
t.Fatalf("NewSignerFromKey(%T): %v", key, err)
}
// The agent should start up empty.
if keys, err := agent.List(); err != nil {
t.Fatalf("RequestIdentities: %v", err)
} else if len(keys) > 0 {
t.Fatalf("got %d keys, want 0: %v", len(keys), keys)
}
// Attempt to insert the key, with certificate if specified.
var pubKey ssh.PublicKey
if cert != nil {
err = agent.Add(key, cert, "comment")
pubKey = cert
} else {
err = agent.Add(key, nil, "comment")
pubKey = signer.PublicKey()
}
if err != nil {
t.Fatalf("insert(%T): %v", key, err)
}
// Did the key get inserted successfully?
if keys, err := agent.List(); err != nil {
t.Fatalf("List: %v", err)
} else if len(keys) != 1 {
t.Fatalf("got %v, want 1 key", keys)
} else if keys[0].Comment != "comment" {
t.Fatalf("key comment: got %v, want %v", keys[0].Comment, "comment")
} else if !bytes.Equal(keys[0].Blob, pubKey.Marshal()) {
t.Fatalf("key mismatch")
}
// Can the agent make a valid signature?
data := []byte("hello")
sig, err := agent.Sign(pubKey, data)
if err != nil {
t.Fatalf("Sign(%s): %v", pubKey.Type(), err)
}
if err := pubKey.Verify(data, sig); err != nil {
t.Fatalf("Verify(%s): %v", pubKey.Type(), err)
}
}
// 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")
}
func (c *SSHCluster) hostKeyCallback(hostname string, remote net.Addr, key ssh.PublicKey) error {
if c.knownHosts == nil {
if err := c.parseKnownHosts(); err != nil {
return err
}
}
err := c.knownHosts.HostKeyCallback(hostname, remote, key)
if err == knownhosts.HostNotFoundError {
fingerprint := c.fingerprintSSHKey(key)
hostnameFormatted := hostname
remoteAddr := remote.String()
if remoteAddr != hostname {
hostnameFormatted = fmt.Sprintf("%s (%s)", hostname, remoteAddr)
}
if c.base.YesNoPrompt(fmt.Sprintf("The authenticity of host '%s' can't be established.\n%s key fingerprint is %s.\nAre you sure you want to continue connecting?", hostnameFormatted, key.Type(), fingerprint)) {
c.base.SendLog(fmt.Sprintf("Trusting '%s' with key fingerprint %s", hostnameFormatted, fingerprint))
file, err := os.OpenFile(c.knownHostsPath(), os.O_CREATE|os.O_WRONLY|os.O_APPEND, os.FileMode(0644))
if err != nil {
c.base.SendLog(fmt.Sprintf("WARNING: Can't write to %s: %s", c.knownHostsPath(), err))
} else {
defer file.Close()
}
c.knownHosts.AppendHost(hostname, key, file)
return nil
}
}
return err
}
func (c *SSHCluster) fingerprintSSHKey(publicKey ssh.PublicKey) string {
hash := sha256.New()
hash.Write(publicKey.Marshal())
return fmt.Sprintf("SHA256:%s", base64.StdEncoding.EncodeToString(hash.Sum(nil)))
}
func (c *client) Remove(key ssh.PublicKey) error {
req := ssh.Marshal(&agentRemoveIdentityMsg{
KeyBlob: key.Marshal(),
})
return c.simpleCall(req)
}
func (k *storedHostKey) Add(key ssh.PublicKey) {
if k.keys == nil {
k.keys = map[string][]byte{}
}
k.keys[key.Type()] = key.Marshal()
}
