fix auth; update deps

vendor/golang.org/x/crypto/ssh/keys.go

@@ -904,6 +904,10 @@ func (k *skECDSAPublicKey) Verify(data []byte, sig *Signature) error {
 	return errors.New("ssh: signature did not verify")
 }
 
+func (k *skECDSAPublicKey) CryptoPublicKey() crypto.PublicKey {
+	return &k.PublicKey
+}
+
 type skEd25519PublicKey struct {
 	// application is a URL-like string, typically "ssh:" for SSH.
 	// see openssh/PROTOCOL.u2f for details.
@@ -1000,6 +1004,10 @@ func (k *skEd25519PublicKey) Verify(data []byte, sig *Signature) error {
 	return nil
 }
 
+func (k *skEd25519PublicKey) CryptoPublicKey() crypto.PublicKey {
+	return k.PublicKey
+}
+
 // 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