From 649bf79117e30895108b7782d62daafd07bc5e6e Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Sun, 22 May 2016 01:23:33 +0100 Subject: Use govendor --- vendor/golang.org/x/crypto/ssh/agent/client.go | 656 ++++++++++++++++++++++++ vendor/golang.org/x/crypto/ssh/agent/forward.go | 103 ++++ vendor/golang.org/x/crypto/ssh/agent/keyring.go | 184 +++++++ vendor/golang.org/x/crypto/ssh/agent/server.go | 420 +++++++++++++++ 4 files changed, 1363 insertions(+) create mode 100644 vendor/golang.org/x/crypto/ssh/agent/client.go create mode 100644 vendor/golang.org/x/crypto/ssh/agent/forward.go create mode 100644 vendor/golang.org/x/crypto/ssh/agent/keyring.go create mode 100644 vendor/golang.org/x/crypto/ssh/agent/server.go (limited to 'vendor/golang.org/x/crypto/ssh/agent') diff --git a/vendor/golang.org/x/crypto/ssh/agent/client.go b/vendor/golang.org/x/crypto/ssh/agent/client.go new file mode 100644 index 0000000..11d3094 --- /dev/null +++ b/vendor/golang.org/x/crypto/ssh/agent/client.go @@ -0,0 +1,656 @@ +// 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) +} + +// 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 +} + +// 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 +) + +// 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"` +} + +// 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"` +} + +// Insert 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, agentConstrainLifetime) + + var secsBytes [4]byte + binary.BigEndian.PutUint32(secsBytes[:], secs) + constraints = append(constraints, secsBytes[:]...) + } + + if key.ConfirmBeforeUse { + constraints = append(constraints, agentConstrainConfirm) + } + + if cert := key.Certificate; cert == nil { + return c.insertKey(key.PrivateKey, key.Comment, constraints) + } else { + 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, + }) + case *ecdsa.PrivateKey: + req = ssh.Marshal(ecdsaCertMsg{ + Type: cert.Type(), + CertBytes: cert.Marshal(), + D: k.D, + Comments: comment, + }) + case ed25519.PrivateKey: + req = ssh.Marshal(ed25519CertMsg{ + Type: cert.Type(), + CertBytes: cert.Marshal(), + Pub: []byte(k)[32:], + Priv: []byte(k), + Comments: comment, + }) + 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) +} diff --git a/vendor/golang.org/x/crypto/ssh/agent/forward.go b/vendor/golang.org/x/crypto/ssh/agent/forward.go new file mode 100644 index 0000000..fd24ba9 --- /dev/null +++ b/vendor/golang.org/x/crypto/ssh/agent/forward.go @@ -0,0 +1,103 @@ +// 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() +} diff --git a/vendor/golang.org/x/crypto/ssh/agent/keyring.go b/vendor/golang.org/x/crypto/ssh/agent/keyring.go new file mode 100644 index 0000000..12ffa82 --- /dev/null +++ b/vendor/golang.org/x/crypto/ssh/agent/keyring.go @@ -0,0 +1,184 @@ +// 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" + + "golang.org/x/crypto/ssh" +) + +type privKey struct { + signer ssh.Signer + comment string +} + +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 +} + +// 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 +} + +// Lock locks the agent. Sign and Remove will fail, and List will empty 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 +} + +// 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 + } + + 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 + } + } + + r.keys = append(r.keys, privKey{signer, key.Comment}) + + 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") +} + +// 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 + } + + s := make([]ssh.Signer, 0, len(r.keys)) + for _, k := range r.keys { + s = append(s, k.signer) + } + return s, nil +} diff --git a/vendor/golang.org/x/crypto/ssh/agent/server.go b/vendor/golang.org/x/crypto/ssh/agent/server.go new file mode 100644 index 0000000..c562fa6 --- /dev/null +++ b/vendor/golang.org/x/crypto/ssh/agent/server.go @@ -0,0 +1,420 @@ +// 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/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 agentLockMsg + 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 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() + + return &AddedKey{PrivateKey: priv, Comment: k.Comments}, 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, + } + + return &AddedKey{PrivateKey: priv, Comment: k.Comments}, 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 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 + } + + return &AddedKey{PrivateKey: &priv, Comment: k.Comments}, 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() + + return &AddedKey{PrivateKey: &priv, Certificate: cert, Comment: k.Comments}, 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, + } + + return &AddedKey{PrivateKey: priv, Certificate: cert, Comment: k.Comments}, 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 + } + + return &AddedKey{PrivateKey: priv, Certificate: cert, Comment: k.Comments}, 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 = parseECDSACert(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) + 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 + } + } +} -- cgit v1.2.3