SSH/Agent: make it so identities include key comments and add new

findIdentityByPublicKey() method

phpseclib/System/SSH/Agent.php

@@ -33,6 +33,7 @@
 namespace phpseclib3\System\SSH;
 
 use phpseclib3\Common\Functions\Strings;
+use phpseclib3\Crypt\Common\PublicKey;
 use phpseclib3\Crypt\PublicKeyLoader;
 use phpseclib3\Crypt\RSA;
 use phpseclib3\Exception\BadConfigurationException;
@@ -192,7 +193,8 @@ class Agent
             if (isset($key)) {
                 $identity = (new Identity($this->fsock))
                     ->withPublicKey($key)
-                    ->withPublicKeyBlob($key_blob);
+                    ->withPublicKeyBlob($key_blob)
+                    ->withComment($comment);
                 $identities[] = $identity;
                 unset($key);
             }
@@ -201,6 +203,24 @@ class Agent
         return $identities;
     }
 
+    /**
+     * Returns the SSH Agent identity matching a given public key or null if no identity is found
+     *
+     * @return ?Identity
+     */
+    public function findIdentityByPublicKey(PublicKey $key)
+    {
+        $identities = $this->requestIdentities();
+        $key = (string) $key;
+        foreach ($identities as $identity) {
+            if (((string) $identity->getPublicKey()) == $key) {
+                return $identity;
+            }
+        }
+
+        return null;
+    }
+
     /**
      * Signal that agent forwarding should
      * be requested when a channel is opened

phpseclib/System/SSH/Agent/Identity.php

@@ -79,6 +79,13 @@ class Identity implements PrivateKey
      */
     private $flags = 0;
 
+    /**
+     * Comment
+     *
+     * @var null|string
+     */
+    private $comment;
+
     /**
      * Curve Aliases
      *
@@ -141,10 +148,9 @@ class Identity implements PrivateKey
      *
      * Wrapper for $this->key->getPublicKey()
      *
-     * @param string $type optional
      * @return mixed
      */
-    public function getPublicKey($type = 'PKCS8')
+    public function getPublicKey()
     {
         return $this->key;
     }
@@ -317,4 +323,24 @@ class Identity implements PrivateKey
     {
         throw new \RuntimeException('ssh-agent does not provide a mechanism to get the private key');
     }
+
+    /**
+     * Sets the comment
+     */
+    public function withComment($comment = null)
+    {
+        $new = clone $this;
+        $new->comment = $comment;
+        return $new;
+    }
+
+    /**
+     * Returns the comment
+     *
+     * @return null|string
+     */
+    public function getComment()
+    {
+        return $this->comment;
+    }
 }