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-rw-r--r--vendor/golang.org/x/crypto/ssh/keys.go846
1 files changed, 846 insertions, 0 deletions
diff --git a/vendor/golang.org/x/crypto/ssh/keys.go b/vendor/golang.org/x/crypto/ssh/keys.go
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+++ b/vendor/golang.org/x/crypto/ssh/keys.go
@@ -0,0 +1,846 @@
+// 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 ssh
+
+import (
+ "bytes"
+ "crypto"
+ "crypto/dsa"
+ "crypto/ecdsa"
+ "crypto/elliptic"
+ "crypto/rsa"
+ "crypto/x509"
+ "encoding/asn1"
+ "encoding/base64"
+ "encoding/pem"
+ "errors"
+ "fmt"
+ "io"
+ "math/big"
+ "strings"
+
+ "golang.org/x/crypto/ed25519"
+)
+
+// These constants represent the algorithm names for key types supported by this
+// package.
+const (
+ KeyAlgoRSA = "ssh-rsa"
+ KeyAlgoDSA = "ssh-dss"
+ KeyAlgoECDSA256 = "ecdsa-sha2-nistp256"
+ KeyAlgoECDSA384 = "ecdsa-sha2-nistp384"
+ KeyAlgoECDSA521 = "ecdsa-sha2-nistp521"
+ KeyAlgoED25519 = "ssh-ed25519"
+)
+
+// parsePubKey parses a public key of the given algorithm.
+// Use ParsePublicKey for keys with prepended algorithm.
+func parsePubKey(in []byte, algo string) (pubKey PublicKey, rest []byte, err error) {
+ switch algo {
+ case KeyAlgoRSA:
+ return parseRSA(in)
+ case KeyAlgoDSA:
+ return parseDSA(in)
+ case KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521:
+ return parseECDSA(in)
+ case KeyAlgoED25519:
+ return parseED25519(in)
+ case CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoED25519v01:
+ cert, err := parseCert(in, certToPrivAlgo(algo))
+ if err != nil {
+ return nil, nil, err
+ }
+ return cert, nil, nil
+ }
+ return nil, nil, fmt.Errorf("ssh: unknown key algorithm: %v", algo)
+}
+
+// parseAuthorizedKey parses a public key in OpenSSH authorized_keys format
+// (see sshd(8) manual page) once the options and key type fields have been
+// removed.
+func parseAuthorizedKey(in []byte) (out PublicKey, comment string, err error) {
+ in = bytes.TrimSpace(in)
+
+ i := bytes.IndexAny(in, " \t")
+ if i == -1 {
+ i = len(in)
+ }
+ base64Key := in[:i]
+
+ key := make([]byte, base64.StdEncoding.DecodedLen(len(base64Key)))
+ n, err := base64.StdEncoding.Decode(key, base64Key)
+ if err != nil {
+ return nil, "", err
+ }
+ key = key[:n]
+ out, err = ParsePublicKey(key)
+ if err != nil {
+ return nil, "", err
+ }
+ comment = string(bytes.TrimSpace(in[i:]))
+ return out, comment, nil
+}
+
+// ParseKnownHosts parses an entry in the format of the known_hosts file.
+//
+// The known_hosts format is documented in the sshd(8) manual page. This
+// function will parse a single entry from in. On successful return, marker
+// will contain the optional marker value (i.e. "cert-authority" or "revoked")
+// or else be empty, hosts will contain the hosts that this entry matches,
+// pubKey will contain the public key and comment will contain any trailing
+// comment at the end of the line. See the sshd(8) manual page for the various
+// forms that a host string can take.
+//
+// The unparsed remainder of the input will be returned in rest. This function
+// can be called repeatedly to parse multiple entries.
+//
+// If no entries were found in the input then err will be io.EOF. Otherwise a
+// non-nil err value indicates a parse error.
+func ParseKnownHosts(in []byte) (marker string, hosts []string, pubKey PublicKey, comment string, rest []byte, err error) {
+ for len(in) > 0 {
+ end := bytes.IndexByte(in, '\n')
+ if end != -1 {
+ rest = in[end+1:]
+ in = in[:end]
+ } else {
+ rest = nil
+ }
+
+ end = bytes.IndexByte(in, '\r')
+ if end != -1 {
+ in = in[:end]
+ }
+
+ in = bytes.TrimSpace(in)
+ if len(in) == 0 || in[0] == '#' {
+ in = rest
+ continue
+ }
+
+ i := bytes.IndexAny(in, " \t")
+ if i == -1 {
+ in = rest
+ continue
+ }
+
+ // Strip out the begining of the known_host key.
+ // This is either an optional marker or a (set of) hostname(s).
+ keyFields := bytes.Fields(in)
+ if len(keyFields) < 3 || len(keyFields) > 5 {
+ return "", nil, nil, "", nil, errors.New("ssh: invalid entry in known_hosts data")
+ }
+
+ // keyFields[0] is either "@cert-authority", "@revoked" or a comma separated
+ // list of hosts
+ marker := ""
+ if keyFields[0][0] == '@' {
+ marker = string(keyFields[0][1:])
+ keyFields = keyFields[1:]
+ }
+
+ hosts := string(keyFields[0])
+ // keyFields[1] contains the key type (e.g. “ssh-rsa”).
+ // However, that information is duplicated inside the
+ // base64-encoded key and so is ignored here.
+
+ key := bytes.Join(keyFields[2:], []byte(" "))
+ if pubKey, comment, err = parseAuthorizedKey(key); err != nil {
+ return "", nil, nil, "", nil, err
+ }
+
+ return marker, strings.Split(hosts, ","), pubKey, comment, rest, nil
+ }
+
+ return "", nil, nil, "", nil, io.EOF
+}
+
+// ParseAuthorizedKeys parses a public key from an authorized_keys
+// file used in OpenSSH according to the sshd(8) manual page.
+func ParseAuthorizedKey(in []byte) (out PublicKey, comment string, options []string, rest []byte, err error) {
+ for len(in) > 0 {
+ end := bytes.IndexByte(in, '\n')
+ if end != -1 {
+ rest = in[end+1:]
+ in = in[:end]
+ } else {
+ rest = nil
+ }
+
+ end = bytes.IndexByte(in, '\r')
+ if end != -1 {
+ in = in[:end]
+ }
+
+ in = bytes.TrimSpace(in)
+ if len(in) == 0 || in[0] == '#' {
+ in = rest
+ continue
+ }
+
+ i := bytes.IndexAny(in, " \t")
+ if i == -1 {
+ in = rest
+ continue
+ }
+
+ if out, comment, err = parseAuthorizedKey(in[i:]); err == nil {
+ return out, comment, options, rest, nil
+ }
+
+ // No key type recognised. Maybe there's an options field at
+ // the beginning.
+ var b byte
+ inQuote := false
+ var candidateOptions []string
+ optionStart := 0
+ for i, b = range in {
+ isEnd := !inQuote && (b == ' ' || b == '\t')
+ if (b == ',' && !inQuote) || isEnd {
+ if i-optionStart > 0 {
+ candidateOptions = append(candidateOptions, string(in[optionStart:i]))
+ }
+ optionStart = i + 1
+ }
+ if isEnd {
+ break
+ }
+ if b == '"' && (i == 0 || (i > 0 && in[i-1] != '\\')) {
+ inQuote = !inQuote
+ }
+ }
+ for i < len(in) && (in[i] == ' ' || in[i] == '\t') {
+ i++
+ }
+ if i == len(in) {
+ // Invalid line: unmatched quote
+ in = rest
+ continue
+ }
+
+ in = in[i:]
+ i = bytes.IndexAny(in, " \t")
+ if i == -1 {
+ in = rest
+ continue
+ }
+
+ if out, comment, err = parseAuthorizedKey(in[i:]); err == nil {
+ options = candidateOptions
+ return out, comment, options, rest, nil
+ }
+
+ in = rest
+ continue
+ }
+
+ return nil, "", nil, nil, errors.New("ssh: no key found")
+}
+
+// ParsePublicKey parses an SSH public key formatted for use in
+// the SSH wire protocol according to RFC 4253, section 6.6.
+func ParsePublicKey(in []byte) (out PublicKey, err error) {
+ algo, in, ok := parseString(in)
+ if !ok {
+ return nil, errShortRead
+ }
+ var rest []byte
+ out, rest, err = parsePubKey(in, string(algo))
+ if len(rest) > 0 {
+ return nil, errors.New("ssh: trailing junk in public key")
+ }
+
+ return out, err
+}
+
+// MarshalAuthorizedKey serializes key for inclusion in an OpenSSH
+// authorized_keys file. The return value ends with newline.
+func MarshalAuthorizedKey(key PublicKey) []byte {
+ b := &bytes.Buffer{}
+ b.WriteString(key.Type())
+ b.WriteByte(' ')
+ e := base64.NewEncoder(base64.StdEncoding, b)
+ e.Write(key.Marshal())
+ e.Close()
+ b.WriteByte('\n')
+ return b.Bytes()
+}
+
+// PublicKey is an abstraction of different types of public keys.
+type PublicKey interface {
+ // Type returns the key's type, e.g. "ssh-rsa".
+ Type() string
+
+ // Marshal returns the serialized key data in SSH wire format,
+ // with the name prefix.
+ Marshal() []byte
+
+ // Verify that sig is a signature on the given data using this
+ // key. This function will hash the data appropriately first.
+ Verify(data []byte, sig *Signature) error
+}
+
+// A Signer can create signatures that verify against a public key.
+type Signer interface {
+ // PublicKey returns an associated PublicKey instance.
+ PublicKey() PublicKey
+
+ // Sign returns raw signature for the given data. This method
+ // will apply the hash specified for the keytype to the data.
+ Sign(rand io.Reader, data []byte) (*Signature, error)
+}
+
+type rsaPublicKey rsa.PublicKey
+
+func (r *rsaPublicKey) Type() string {
+ return "ssh-rsa"
+}
+
+// parseRSA parses an RSA key according to RFC 4253, section 6.6.
+func parseRSA(in []byte) (out PublicKey, rest []byte, err error) {
+ var w struct {
+ E *big.Int
+ N *big.Int
+ Rest []byte `ssh:"rest"`
+ }
+ if err := Unmarshal(in, &w); err != nil {
+ return nil, nil, err
+ }
+
+ if w.E.BitLen() > 24 {
+ return nil, nil, errors.New("ssh: exponent too large")
+ }
+ e := w.E.Int64()
+ if e < 3 || e&1 == 0 {
+ return nil, nil, errors.New("ssh: incorrect exponent")
+ }
+
+ var key rsa.PublicKey
+ key.E = int(e)
+ key.N = w.N
+ return (*rsaPublicKey)(&key), w.Rest, nil
+}
+
+func (r *rsaPublicKey) Marshal() []byte {
+ e := new(big.Int).SetInt64(int64(r.E))
+ // RSA publickey struct layout should match the struct used by
+ // parseRSACert in the x/crypto/ssh/agent package.
+ wirekey := struct {
+ Name string
+ E *big.Int
+ N *big.Int
+ }{
+ KeyAlgoRSA,
+ e,
+ r.N,
+ }
+ return Marshal(&wirekey)
+}
+
+func (r *rsaPublicKey) Verify(data []byte, sig *Signature) error {
+ if sig.Format != r.Type() {
+ return fmt.Errorf("ssh: signature type %s for key type %s", sig.Format, r.Type())
+ }
+ h := crypto.SHA1.New()
+ h.Write(data)
+ digest := h.Sum(nil)
+ return rsa.VerifyPKCS1v15((*rsa.PublicKey)(r), crypto.SHA1, digest, sig.Blob)
+}
+
+type dsaPublicKey dsa.PublicKey
+
+func (r *dsaPublicKey) Type() string {
+ return "ssh-dss"
+}
+
+// parseDSA parses an DSA key according to RFC 4253, section 6.6.
+func parseDSA(in []byte) (out PublicKey, rest []byte, err error) {
+ var w struct {
+ P, Q, G, Y *big.Int
+ Rest []byte `ssh:"rest"`
+ }
+ if err := Unmarshal(in, &w); err != nil {
+ return nil, nil, err
+ }
+
+ key := &dsaPublicKey{
+ Parameters: dsa.Parameters{
+ P: w.P,
+ Q: w.Q,
+ G: w.G,
+ },
+ Y: w.Y,
+ }
+ return key, w.Rest, nil
+}
+
+func (k *dsaPublicKey) Marshal() []byte {
+ // DSA publickey struct layout should match the struct used by
+ // parseDSACert in the x/crypto/ssh/agent package.
+ w := struct {
+ Name string
+ P, Q, G, Y *big.Int
+ }{
+ k.Type(),
+ k.P,
+ k.Q,
+ k.G,
+ k.Y,
+ }
+
+ return Marshal(&w)
+}
+
+func (k *dsaPublicKey) Verify(data []byte, sig *Signature) error {
+ if sig.Format != k.Type() {
+ return fmt.Errorf("ssh: signature type %s for key type %s", sig.Format, k.Type())
+ }
+ h := crypto.SHA1.New()
+ h.Write(data)
+ digest := h.Sum(nil)
+
+ // Per RFC 4253, section 6.6,
+ // The value for 'dss_signature_blob' is encoded as a string containing
+ // r, followed by s (which are 160-bit integers, without lengths or
+ // padding, unsigned, and in network byte order).
+ // For DSS purposes, sig.Blob should be exactly 40 bytes in length.
+ if len(sig.Blob) != 40 {
+ return errors.New("ssh: DSA signature parse error")
+ }
+ r := new(big.Int).SetBytes(sig.Blob[:20])
+ s := new(big.Int).SetBytes(sig.Blob[20:])
+ if dsa.Verify((*dsa.PublicKey)(k), digest, r, s) {
+ return nil
+ }
+ return errors.New("ssh: signature did not verify")
+}
+
+type dsaPrivateKey struct {
+ *dsa.PrivateKey
+}
+
+func (k *dsaPrivateKey) PublicKey() PublicKey {
+ return (*dsaPublicKey)(&k.PrivateKey.PublicKey)
+}
+
+func (k *dsaPrivateKey) Sign(rand io.Reader, data []byte) (*Signature, error) {
+ h := crypto.SHA1.New()
+ h.Write(data)
+ digest := h.Sum(nil)
+ r, s, err := dsa.Sign(rand, k.PrivateKey, digest)
+ if err != nil {
+ return nil, err
+ }
+
+ sig := make([]byte, 40)
+ rb := r.Bytes()
+ sb := s.Bytes()
+
+ copy(sig[20-len(rb):20], rb)
+ copy(sig[40-len(sb):], sb)
+
+ return &Signature{
+ Format: k.PublicKey().Type(),
+ Blob: sig,
+ }, nil
+}
+
+type ecdsaPublicKey ecdsa.PublicKey
+
+func (key *ecdsaPublicKey) Type() string {
+ return "ecdsa-sha2-" + key.nistID()
+}
+
+func (key *ecdsaPublicKey) nistID() string {
+ switch key.Params().BitSize {
+ case 256:
+ return "nistp256"
+ case 384:
+ return "nistp384"
+ case 521:
+ return "nistp521"
+ }
+ panic("ssh: unsupported ecdsa key size")
+}
+
+type ed25519PublicKey ed25519.PublicKey
+
+func (key ed25519PublicKey) Type() string {
+ return KeyAlgoED25519
+}
+
+func parseED25519(in []byte) (out PublicKey, rest []byte, err error) {
+ var w struct {
+ KeyBytes []byte
+ Rest []byte `ssh:"rest"`
+ }
+
+ if err := Unmarshal(in, &w); err != nil {
+ return nil, nil, err
+ }
+
+ key := ed25519.PublicKey(w.KeyBytes)
+
+ return (ed25519PublicKey)(key), w.Rest, nil
+}
+
+func (key ed25519PublicKey) Marshal() []byte {
+ w := struct {
+ Name string
+ KeyBytes []byte
+ }{
+ KeyAlgoED25519,
+ []byte(key),
+ }
+ return Marshal(&w)
+}
+
+func (key ed25519PublicKey) Verify(b []byte, sig *Signature) error {
+ if sig.Format != key.Type() {
+ return fmt.Errorf("ssh: signature type %s for key type %s", sig.Format, key.Type())
+ }
+
+ edKey := (ed25519.PublicKey)(key)
+ if ok := ed25519.Verify(edKey, b, sig.Blob); !ok {
+ return errors.New("ssh: signature did not verify")
+ }
+
+ return nil
+}
+
+func supportedEllipticCurve(curve elliptic.Curve) bool {
+ return curve == elliptic.P256() || curve == elliptic.P384() || curve == elliptic.P521()
+}
+
+// ecHash returns the hash to match the given elliptic curve, see RFC
+// 5656, section 6.2.1
+func ecHash(curve elliptic.Curve) crypto.Hash {
+ bitSize := curve.Params().BitSize
+ switch {
+ case bitSize <= 256:
+ return crypto.SHA256
+ case bitSize <= 384:
+ return crypto.SHA384
+ }
+ return crypto.SHA512
+}
+
+// parseECDSA parses an ECDSA key according to RFC 5656, section 3.1.
+func parseECDSA(in []byte) (out PublicKey, rest []byte, err error) {
+ var w struct {
+ Curve string
+ KeyBytes []byte
+ Rest []byte `ssh:"rest"`
+ }
+
+ if err := Unmarshal(in, &w); err != nil {
+ return nil, nil, err
+ }
+
+ key := new(ecdsa.PublicKey)
+
+ switch w.Curve {
+ case "nistp256":
+ key.Curve = elliptic.P256()
+ case "nistp384":
+ key.Curve = elliptic.P384()
+ case "nistp521":
+ key.Curve = elliptic.P521()
+ default:
+ return nil, nil, errors.New("ssh: unsupported curve")
+ }
+
+ key.X, key.Y = elliptic.Unmarshal(key.Curve, w.KeyBytes)
+ if key.X == nil || key.Y == nil {
+ return nil, nil, errors.New("ssh: invalid curve point")
+ }
+ return (*ecdsaPublicKey)(key), w.Rest, nil
+}
+
+func (key *ecdsaPublicKey) Marshal() []byte {
+ // See RFC 5656, section 3.1.
+ keyBytes := elliptic.Marshal(key.Curve, key.X, key.Y)
+ // ECDSA publickey struct layout should match the struct used by
+ // parseECDSACert in the x/crypto/ssh/agent package.
+ w := struct {
+ Name string
+ ID string
+ Key []byte
+ }{
+ key.Type(),
+ key.nistID(),
+ keyBytes,
+ }
+
+ return Marshal(&w)
+}
+
+func (key *ecdsaPublicKey) Verify(data []byte, sig *Signature) error {
+ if sig.Format != key.Type() {
+ return fmt.Errorf("ssh: signature type %s for key type %s", sig.Format, key.Type())
+ }
+
+ h := ecHash(key.Curve).New()
+ h.Write(data)
+ digest := h.Sum(nil)
+
+ // Per RFC 5656, section 3.1.2,
+ // The ecdsa_signature_blob value has the following specific encoding:
+ // mpint r
+ // mpint s
+ var ecSig struct {
+ R *big.Int
+ S *big.Int
+ }
+
+ if err := Unmarshal(sig.Blob, &ecSig); err != nil {
+ return err
+ }
+
+ if ecdsa.Verify((*ecdsa.PublicKey)(key), digest, ecSig.R, ecSig.S) {
+ return nil
+ }
+ return errors.New("ssh: signature did not verify")
+}
+
+// NewSignerFromKey takes an *rsa.PrivateKey, *dsa.PrivateKey,
+// *ecdsa.PrivateKey or any other crypto.Signer and returns a corresponding
+// Signer instance. ECDSA keys must use P-256, P-384 or P-521.
+func NewSignerFromKey(key interface{}) (Signer, error) {
+ switch key := key.(type) {
+ case crypto.Signer:
+ return NewSignerFromSigner(key)
+ case *dsa.PrivateKey:
+ return &dsaPrivateKey{key}, nil
+ default:
+ return nil, fmt.Errorf("ssh: unsupported key type %T", key)
+ }
+}
+
+type wrappedSigner struct {
+ signer crypto.Signer
+ pubKey PublicKey
+}
+
+// NewSignerFromSigner takes any crypto.Signer implementation and
+// returns a corresponding Signer interface. This can be used, for
+// example, with keys kept in hardware modules.
+func NewSignerFromSigner(signer crypto.Signer) (Signer, error) {
+ pubKey, err := NewPublicKey(signer.Public())
+ if err != nil {
+ return nil, err
+ }
+
+ return &wrappedSigner{signer, pubKey}, nil
+}
+
+func (s *wrappedSigner) PublicKey() PublicKey {
+ return s.pubKey
+}
+
+func (s *wrappedSigner) Sign(rand io.Reader, data []byte) (*Signature, error) {
+ var hashFunc crypto.Hash
+
+ switch key := s.pubKey.(type) {
+ case *rsaPublicKey, *dsaPublicKey:
+ hashFunc = crypto.SHA1
+ case *ecdsaPublicKey:
+ hashFunc = ecHash(key.Curve)
+ case ed25519PublicKey:
+ default:
+ return nil, fmt.Errorf("ssh: unsupported key type %T", key)
+ }
+
+ var digest []byte
+ if hashFunc != 0 {
+ h := hashFunc.New()
+ h.Write(data)
+ digest = h.Sum(nil)
+ } else {
+ digest = data
+ }
+
+ signature, err := s.signer.Sign(rand, digest, hashFunc)
+ if err != nil {
+ return nil, err
+ }
+
+ // crypto.Signer.Sign is expected to return an ASN.1-encoded signature
+ // for ECDSA and DSA, but that's not the encoding expected by SSH, so
+ // re-encode.
+ switch s.pubKey.(type) {
+ case *ecdsaPublicKey, *dsaPublicKey:
+ type asn1Signature struct {
+ R, S *big.Int
+ }
+ asn1Sig := new(asn1Signature)
+ _, err := asn1.Unmarshal(signature, asn1Sig)
+ if err != nil {
+ return nil, err
+ }
+
+ switch s.pubKey.(type) {
+ case *ecdsaPublicKey:
+ signature = Marshal(asn1Sig)
+
+ case *dsaPublicKey:
+ signature = make([]byte, 40)
+ r := asn1Sig.R.Bytes()
+ s := asn1Sig.S.Bytes()
+ copy(signature[20-len(r):20], r)
+ copy(signature[40-len(s):40], s)
+ }
+ }
+
+ return &Signature{
+ Format: s.pubKey.Type(),
+ Blob: signature,
+ }, nil
+}
+
+// NewPublicKey takes an *rsa.PublicKey, *dsa.PublicKey, *ecdsa.PublicKey,
+// ed25519.PublicKey, or any other crypto.Signer and returns a corresponding
+// Signer instance. ECDSA keys must use P-256, P-384 or P-521.
+func NewPublicKey(key interface{}) (PublicKey, error) {
+ switch key := key.(type) {
+ case *rsa.PublicKey:
+ return (*rsaPublicKey)(key), nil
+ case *ecdsa.PublicKey:
+ if !supportedEllipticCurve(key.Curve) {
+ return nil, errors.New("ssh: only P-256, P-384 and P-521 EC keys are supported.")
+ }
+ return (*ecdsaPublicKey)(key), nil
+ case *dsa.PublicKey:
+ return (*dsaPublicKey)(key), nil
+ case ed25519.PublicKey:
+ return (ed25519PublicKey)(key), nil
+ default:
+ return nil, fmt.Errorf("ssh: unsupported key type %T", key)
+ }
+}
+
+// ParsePrivateKey returns a Signer from a PEM encoded private key. It supports
+// the same keys as ParseRawPrivateKey.
+func ParsePrivateKey(pemBytes []byte) (Signer, error) {
+ key, err := ParseRawPrivateKey(pemBytes)
+ if err != nil {
+ return nil, err
+ }
+
+ return NewSignerFromKey(key)
+}
+
+// ParseRawPrivateKey returns a private key from a PEM encoded private key. It
+// supports RSA (PKCS#1), DSA (OpenSSL), and ECDSA private keys.
+func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
+ block, _ := pem.Decode(pemBytes)
+ if block == nil {
+ return nil, errors.New("ssh: no key found")
+ }
+
+ switch block.Type {
+ case "RSA PRIVATE KEY":
+ return x509.ParsePKCS1PrivateKey(block.Bytes)
+ case "EC PRIVATE KEY":
+ return x509.ParseECPrivateKey(block.Bytes)
+ case "DSA PRIVATE KEY":
+ return ParseDSAPrivateKey(block.Bytes)
+ case "OPENSSH PRIVATE KEY":
+ return parseOpenSSHPrivateKey(block.Bytes)
+ default:
+ return nil, fmt.Errorf("ssh: unsupported key type %q", block.Type)
+ }
+}
+
+// ParseDSAPrivateKey returns a DSA private key from its ASN.1 DER encoding, as
+// specified by the OpenSSL DSA man page.
+func ParseDSAPrivateKey(der []byte) (*dsa.PrivateKey, error) {
+ var k struct {
+ Version int
+ P *big.Int
+ Q *big.Int
+ G *big.Int
+ Priv *big.Int
+ Pub *big.Int
+ }
+ rest, err := asn1.Unmarshal(der, &k)
+ if err != nil {
+ return nil, errors.New("ssh: failed to parse DSA key: " + err.Error())
+ }
+ if len(rest) > 0 {
+ return nil, errors.New("ssh: garbage after DSA key")
+ }
+
+ return &dsa.PrivateKey{
+ PublicKey: dsa.PublicKey{
+ Parameters: dsa.Parameters{
+ P: k.P,
+ Q: k.Q,
+ G: k.G,
+ },
+ Y: k.Priv,
+ },
+ X: k.Pub,
+ }, nil
+}
+
+// Implemented based on the documentation at
+// https://github.com/openssh/openssh-portable/blob/master/PROTOCOL.key
+func parseOpenSSHPrivateKey(key []byte) (*ed25519.PrivateKey, error) {
+ magic := append([]byte("openssh-key-v1"), 0)
+ if !bytes.Equal(magic, key[0:len(magic)]) {
+ return nil, errors.New("ssh: invalid openssh private key format")
+ }
+ remaining := key[len(magic):]
+
+ var w struct {
+ CipherName string
+ KdfName string
+ KdfOpts string
+ NumKeys uint32
+ PubKey []byte
+ PrivKeyBlock []byte
+ }
+
+ if err := Unmarshal(remaining, &w); err != nil {
+ return nil, err
+ }
+
+ pk1 := struct {
+ Check1 uint32
+ Check2 uint32
+ Keytype string
+ Pub []byte
+ Priv []byte
+ Comment string
+ Pad []byte `ssh:"rest"`
+ }{}
+
+ if err := Unmarshal(w.PrivKeyBlock, &pk1); err != nil {
+ return nil, err
+ }
+
+ if pk1.Check1 != pk1.Check2 {
+ return nil, errors.New("ssh: checkint mismatch")
+ }
+
+ // we only handle ed25519 keys currently
+ if pk1.Keytype != KeyAlgoED25519 {
+ return nil, errors.New("ssh: unhandled key type")
+ }
+
+ for i, b := range pk1.Pad {
+ if int(b) != i+1 {
+ return nil, errors.New("ssh: padding not as expected")
+ }
+ }
+
+ if len(pk1.Priv) != ed25519.PrivateKeySize {
+ return nil, errors.New("ssh: private key unexpected length")
+ }
+
+ pk := ed25519.PrivateKey(make([]byte, ed25519.PrivateKeySize))
+ copy(pk, pk1.Priv)
+ return &pk, nil
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-27 14:53:48 +0000