diff --git a/phpseclib/Crypt/Common/Fingerprint.php b/phpseclib/Crypt/Common/Fingerprint.php
index 4a81ee9d..0a87d07e 100644
--- a/phpseclib/Crypt/Common/Fingerprint.php
+++ b/phpseclib/Crypt/Common/Fingerprint.php
@@ -40,17 +40,14 @@ trait Fingerprint
      */
     public function getFingerprint($algorithm = 'md5')
     {
-        $type = self::validatePlugin('Keys', 'OpenSSH', 'getBinaryOutput');
+        $type = self::validatePlugin('Keys', 'OpenSSH', 'savePublicKey');
         if ($type === false) {
             return false;
         }
-        $status = $type::getBinaryOutput();
-        $type::setBinaryOutput(true);
-        $key = $this->toString('OpenSSH');
+        $key = $this->toString('OpenSSH', ['binary' => true]);
         if ($key === false) {
             return false;
         }
-        $type::setBinaryOutput($status);
         switch ($algorithm) {
             case 'sha256':
                 $hash = new Hash('sha256');
diff --git a/phpseclib/Crypt/Common/Keys/OpenSSH.php b/phpseclib/Crypt/Common/Keys/OpenSSH.php
index b66beab8..c1b43fa3 100644
--- a/phpseclib/Crypt/Common/Keys/OpenSSH.php
+++ b/phpseclib/Crypt/Common/Keys/OpenSSH.php
@@ -125,15 +125,4 @@ abstract class OpenSSH
     {
         self::$binary = $enabled;
     }
-
-    /**
-     * Returns the current binary output value
-     *
-     * @access public
-     * @return bool
-     */
-    public static function getBinaryOutput()
-    {
-        return (bool) self::$binary;
-    }
 }
diff --git a/phpseclib/Crypt/Common/Keys/PKCS1.php b/phpseclib/Crypt/Common/Keys/PKCS1.php
index 297f1c85..7a16f8bd 100644
--- a/phpseclib/Crypt/Common/Keys/PKCS1.php
+++ b/phpseclib/Crypt/Common/Keys/PKCS1.php
@@ -179,9 +179,10 @@ abstract class PKCS1 extends PKCS
      * @param string $key
      * @param string $type
      * @param string $password
+     * @param array $options optional
      * @return string
      */
-    protected static function wrapPrivateKey($key, $type, $password)
+    protected static function wrapPrivateKey($key, $type, $password, $options = [])
     {
         if (empty($password) || !is_string($password)) {
             return "-----BEGIN $type PRIVATE KEY-----\r\n" .
@@ -189,14 +190,16 @@ abstract class PKCS1 extends PKCS
                    "-----END $type PRIVATE KEY-----";
         }
 
-        $cipher = self::getEncryptionObject(self::$defaultEncryptionAlgorithm);
+        $encryptionAlgorithm = isset($options['encryptionAlgorithm']) ? $options['encryptionAlgorithm'] : self::$defaultEncryptionAlgorithm;
+
+        $cipher = self::getEncryptionObject($encryptionAlgorithm);
         $iv = Random::string($cipher->getBlockLength() >> 3);
         $cipher->setKey(self::generateSymmetricKey($password, $iv, $cipher->getKeyLength() >> 3));
         $cipher->setIV($iv);
         $iv = strtoupper(Hex::encode($iv));
         return "-----BEGIN $type PRIVATE KEY-----\r\n" .
                "Proc-Type: 4,ENCRYPTED\r\n" .
-               "DEK-Info: " . self::$defaultEncryptionAlgorithm . ",$iv\r\n" .
+               "DEK-Info: " . $encryptionAlgorithm. ",$iv\r\n" .
                "\r\n" .
                chunk_split(Base64::encode($cipher->encrypt($key)), 64) .
                "-----END $type PRIVATE KEY-----";
diff --git a/phpseclib/Crypt/Common/Keys/PKCS8.php b/phpseclib/Crypt/Common/Keys/PKCS8.php
index f350ca6d..8b3921a7 100644
--- a/phpseclib/Crypt/Common/Keys/PKCS8.php
+++ b/phpseclib/Crypt/Common/Keys/PKCS8.php
@@ -526,9 +526,10 @@ abstract class PKCS8 extends PKCS
      * @param string $password
      * @param string $oid optional
      * @param string $publicKey optional
+     * @param array $options optional
      * @return string
      */
-    protected static function wrapPrivateKey($key, $attr, $params, $password, $oid = null, $publicKey = '')
+    protected static function wrapPrivateKey($key, $attr, $params, $password, $oid = null, $publicKey = '', $options = [])
     {
         self::initialize_static_variables();
 
@@ -550,18 +551,22 @@ abstract class PKCS8 extends PKCS
         $key = ASN1::encodeDER($key, Maps\OneAsymmetricKey::MAP);
         if (!empty($password) && is_string($password)) {
             $salt = Random::string(8);
-            $iterationCount = self::$defaultIterationCount;
 
-            if (self::$defaultEncryptionAlgorithm == 'id-PBES2') {
-                $crypto = self::getPBES2EncryptionObject(self::$defaultEncryptionScheme);
-                $hash = str_replace('-', '/', substr(self::$defaultPRF, 11));
+            $iterationCount = isset($options['iterationCount']) ? $options['iterationCount'] : self::$defaultIterationCount;
+            $encryptionAlgorithm = isset($options['encryptionAlgorithm']) ? $options['encryptionAlgorithm'] : self::$defaultEncryptionAlgorithm;
+            $encryptionScheme = isset($options['encryptionScheme']) ? $options['encryptionScheme'] : self::$defaultEncryptionScheme;
+            $prf = isset($options['PRF']) ? $options['PRF'] : self::$defaultPRF;
+
+            if ($encryptionAlgorithm == 'id-PBES2') {
+                $crypto = self::getPBES2EncryptionObject($encryptionScheme);
+                $hash = str_replace('-', '/', substr($prf, 11));
                 $kdf = 'pbkdf2';
                 $iv = Random::string($crypto->getBlockLength() >> 3);
 
                 $PBKDF2params = [
                     'salt' => $salt,
                     'iterationCount' => $iterationCount,
-                    'prf' => ['algorithm' => self::$defaultPRF, 'parameters' => null]
+                    'prf' => ['algorithm' => $prf, 'parameters' => null]
                 ];
                 $PBKDF2params = ASN1::encodeDER($PBKDF2params, Maps\PBKDF2params::MAP);
 
@@ -582,7 +587,7 @@ abstract class PKCS8 extends PKCS
                         'parameters' => new ASN1\Element($PBKDF2params)
                     ],
                     'encryptionScheme' => [
-                        'algorithm' => self::$defaultEncryptionScheme,
+                        'algorithm' => $encryptionScheme,
                         'parameters' => $params
                     ]
                 ];
@@ -590,9 +595,9 @@ abstract class PKCS8 extends PKCS
 
                 $crypto->setIV($iv);
             } else {
-                $crypto = self::getPBES1EncryptionObject(self::$defaultEncryptionAlgorithm);
-                $hash = self::getPBES1Hash(self::$defaultEncryptionAlgorithm);
-                $kdf = self::getPBES1KDF(self::$defaultEncryptionAlgorithm);
+                $crypto = self::getPBES1EncryptionObject($encryptionAlgorithm);
+                $hash = self::getPBES1Hash($encryptionAlgorithm);
+                $kdf = self::getPBES1KDF($encryptionAlgorithm);
 
                 $params = [
                     'salt' => $salt,
@@ -605,7 +610,7 @@ abstract class PKCS8 extends PKCS
 
             $key = [
                 'encryptionAlgorithm' => [
-                    'algorithm' => self::$defaultEncryptionAlgorithm,
+                    'algorithm' => $encryptionAlgorithm,
                     'parameters' => new ASN1\Element($params)
                 ],
                 'encryptedData' => $key
diff --git a/phpseclib/Crypt/Common/Keys/PuTTY.php b/phpseclib/Crypt/Common/Keys/PuTTY.php
index 0371552c..11159bba 100644
--- a/phpseclib/Crypt/Common/Keys/PuTTY.php
+++ b/phpseclib/Crypt/Common/Keys/PuTTY.php
@@ -172,9 +172,10 @@ abstract class PuTTY
      * @param string $private
      * @param string $type
      * @param string $password
+     * @param array $options optional
      * @return string
      */
-    protected static function wrapPrivateKey($public, $private, $type, $password)
+    protected static function wrapPrivateKey($public, $private, $type, $password, $options = [])
     {
         $key = "PuTTY-User-Key-File-2: " . $type . "\r\nEncryption: ";
         $encryption = (!empty($password) || is_string($password)) ? 'aes256-cbc' : 'none';
@@ -183,7 +184,8 @@ abstract class PuTTY
 
         $public = Strings::packSSH2('s', $type) . $public;
 
-        $source = Strings::packSSH2('ssss', $type, $encryption, self::$comment, $public);
+        $comment = isset($options['comment']) ? $options['comment'] : self::$comment;
+        $source = Strings::packSSH2('ssss', $type, $encryption, $comment, $public);
 
         $public = Base64::encode($public);
         $key.= "Public-Lines: " . ((strlen($public) + 63) >> 6) . "\r\n";
diff --git a/phpseclib/Crypt/DSA/Keys/OpenSSH.php b/phpseclib/Crypt/DSA/Keys/OpenSSH.php
index 4b4163c8..65a9c417 100644
--- a/phpseclib/Crypt/DSA/Keys/OpenSSH.php
+++ b/phpseclib/Crypt/DSA/Keys/OpenSSH.php
@@ -62,9 +62,10 @@ abstract class OpenSSH extends Progenitor
      * @param \phpseclib\Math\BigInteger $q
      * @param \phpseclib\Math\BigInteger $g
      * @param \phpseclib\Math\BigInteger $y
+     * @param array $options optional
      * @return string
      */
-    public static function savePublicKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y)
+    public static function savePublicKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y, $options = [])
     {
         if ($q->getLength() != 160) {
             throw new \InvalidArgumentException('SSH only supports keys with an N (length of Group Order q) of 160');
@@ -78,11 +79,12 @@ abstract class OpenSSH extends Progenitor
         // mpint     y
         $DSAPublicKey = Strings::packSSH2('siiii', 'ssh-dss', $p, $q, $g, $y);
 
-        if (self::$binary) {
+        if (isset($options['binary']) ? $options['binary'] : self::$binary) {
             return $DSAPublicKey;
         }
 
-        $DSAPublicKey = 'ssh-dss ' . Base64::encode($DSAPublicKey) . ' ' . self::$comment;
+        $comment = isset($options['comment']) ? $options['comment'] : self::$comment;
+        $DSAPublicKey = 'ssh-dss ' . Base64::encode($DSAPublicKey) . ' ' . $comment;
 
         return $DSAPublicKey;
     }
diff --git a/phpseclib/Crypt/DSA/Keys/PKCS1.php b/phpseclib/Crypt/DSA/Keys/PKCS1.php
index 7d569409..54e08208 100644
--- a/phpseclib/Crypt/DSA/Keys/PKCS1.php
+++ b/phpseclib/Crypt/DSA/Keys/PKCS1.php
@@ -113,9 +113,10 @@ abstract class PKCS1 extends Progenitor
      * @param \phpseclib\Math\BigInteger $x
      * @param \phpseclib\Math\BigInteger $y
      * @param string $password optional
+     * @param array $options optional
      * @return string
      */
-    public static function savePrivateKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y, BigInteger $x, $password = '')
+    public static function savePrivateKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y, BigInteger $x, $password = '', $options = [])
     {
         $key = [
             'version' => 0,
@@ -128,7 +129,7 @@ abstract class PKCS1 extends Progenitor
 
         $key = ASN1::encodeDER($key, Maps\DSAPrivateKey::MAP);
 
-        return self::wrapPrivateKey($key, 'DSA', $password);
+        return self::wrapPrivateKey($key, 'DSA', $password, $options);
     }
 
     /**
diff --git a/phpseclib/Crypt/DSA/Keys/PKCS8.php b/phpseclib/Crypt/DSA/Keys/PKCS8.php
index f5447b46..661b723c 100644
--- a/phpseclib/Crypt/DSA/Keys/PKCS8.php
+++ b/phpseclib/Crypt/DSA/Keys/PKCS8.php
@@ -127,9 +127,10 @@ abstract class PKCS8 extends Progenitor
      * @param \phpseclib\Math\BigInteger $x
      * @param \phpseclib\Math\BigInteger $y
      * @param string $password optional
+     * @param array $options optional
      * @return string
      */
-    public static function savePrivateKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y, BigInteger $x, $password = '')
+    public static function savePrivateKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y, BigInteger $x, $password = '', $options = [])
     {
         $params = [
             'p' => $p,
@@ -139,7 +140,7 @@ abstract class PKCS8 extends Progenitor
         $params = ASN1::encodeDER($params, Maps\DSAParams::MAP);
         $params = new ASN1\Element($params);
         $key = ASN1::encodeDER($x, Maps\DSAPublicKey::MAP);
-        return self::wrapPrivateKey($key, [], $params, $password);
+        return self::wrapPrivateKey($key, [], $params, $password, $options);
     }
 
     /**
@@ -150,9 +151,10 @@ abstract class PKCS8 extends Progenitor
      * @param \phpseclib\Math\BigInteger $q
      * @param \phpseclib\Math\BigInteger $g
      * @param \phpseclib\Math\BigInteger $y
+     * @param array $options optional
      * @return string
      */
-    public static function savePublicKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y)
+    public static function savePublicKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y, $options = [])
     {
         $params = [
             'p' => $p,
diff --git a/phpseclib/Crypt/DSA/Keys/PuTTY.php b/phpseclib/Crypt/DSA/Keys/PuTTY.php
index 2f85fcfe..03031fb6 100644
--- a/phpseclib/Crypt/DSA/Keys/PuTTY.php
+++ b/phpseclib/Crypt/DSA/Keys/PuTTY.php
@@ -91,9 +91,10 @@ abstract class PuTTY extends Progenitor
      * @param \phpseclib\Math\BigInteger $y
      * @param \phpseclib\Math\BigInteger $x
      * @param string $password optional
+     * @param array $options optional
      * @return string
      */
-    public static function savePrivateKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y, BigInteger $x, $password = false)
+    public static function savePrivateKey(BigInteger $p, BigInteger $q, BigInteger $g, BigInteger $y, BigInteger $x, $password = false, $options = [])
     {
         if ($q->getLength() != 160) {
             throw new \InvalidArgumentException('SSH only supports keys with an N (length of Group Order q) of 160');
@@ -102,7 +103,7 @@ abstract class PuTTY extends Progenitor
         $public = Strings::packSSH2('iiii', $p, $q, $g, $y);
         $private = Strings::packSSH2('i', $x);
 
-        return self::wrapPrivateKey($public, $private, 'ssh-dsa', $password);
+        return self::wrapPrivateKey($public, $private, 'ssh-dsa', $password, $options);
     }
 
     /**
diff --git a/phpseclib/Crypt/DSA/Parameters.php b/phpseclib/Crypt/DSA/Parameters.php
index 7a26b29a..b97c1dfe 100644
--- a/phpseclib/Crypt/DSA/Parameters.php
+++ b/phpseclib/Crypt/DSA/Parameters.php
@@ -25,15 +25,16 @@ use phpseclib\Crypt\DSA;
 class Parameters extends DSA
 {
     /**
-     * Returns the public key
+     * Returns the parameters
      *
      * @param string $type
+     * @param array $options optional
      * @return string
      */
-    public function toString($type = 'PKCS1')
+    public function toString($type = 'PKCS1', $options = [])
     {
         $type = self::validatePlugin('Keys', 'PKCS1', 'saveParameters');
 
-        return $type::saveParameters($this->p, $this->q, $this->g);
+        return $type::saveParameters($this->p, $this->q, $this->g, $options);
     }
 }
diff --git a/phpseclib/Crypt/DSA/PrivateKey.php b/phpseclib/Crypt/DSA/PrivateKey.php
index 7434ca9e..32e9fbda 100644
--- a/phpseclib/Crypt/DSA/PrivateKey.php
+++ b/phpseclib/Crypt/DSA/PrivateKey.php
@@ -144,9 +144,10 @@ class PrivateKey extends DSA implements Common\PrivateKey
      * Returns the private key
      *
      * @param string $type
+     * @param array $options optional
      * @return string
      */
-    public function toString($type)
+    public function toString($type, $options = [])
     {
         $type = self::validatePlugin('Keys', $type, 'savePrivateKey');
 
@@ -154,6 +155,6 @@ class PrivateKey extends DSA implements Common\PrivateKey
             $this->y = $this->g->powMod($this->x, $this->p);
         }
 
-        return $type::savePrivateKey($this->p, $this->q, $this->g, $this->y, $this->x, $this->password);
+        return $type::savePrivateKey($this->p, $this->q, $this->g, $this->y, $this->x, $this->password, $options);
     }
 }
diff --git a/phpseclib/Crypt/DSA/PublicKey.php b/phpseclib/Crypt/DSA/PublicKey.php
index e8aca903..72ff5025 100644
--- a/phpseclib/Crypt/DSA/PublicKey.php
+++ b/phpseclib/Crypt/DSA/PublicKey.php
@@ -80,12 +80,13 @@ class PublicKey extends DSA implements Common\PublicKey
      * Returns the public key
      *
      * @param string $type
+     * @param array $options optional
      * @return string
      */
-    public function toString($type)
+    public function toString($type, $options = [])
     {
         $type = self::validatePlugin('Keys', $type, 'savePublicKey');
 
-        return $type::savePublicKey($this->p, $this->q, $this->g, $this->y);
+        return $type::savePublicKey($this->p, $this->q, $this->g, $this->y, $options);
     }
 }
diff --git a/phpseclib/Crypt/ECDSA/Keys/OpenSSH.php b/phpseclib/Crypt/ECDSA/Keys/OpenSSH.php
index 1ebeb270..c4b07341 100644
--- a/phpseclib/Crypt/ECDSA/Keys/OpenSSH.php
+++ b/phpseclib/Crypt/ECDSA/Keys/OpenSSH.php
@@ -186,10 +186,13 @@ abstract class OpenSSH extends Progenitor
      * @access public
      * @param \phpseclib\Crypt\ECDSA\BaseCurves\Base $curve
      * @param \phpseclib\Math\Common\FiniteField\Integer[] $publicKey
+     * @param array $options optional
      * @return string
      */
-    public static function savePublicKey(BaseCurve $curve, array $publicKey)
+    public static function savePublicKey(BaseCurve $curve, array $publicKey, $options = [])
     {
+        $comment = isset($options['comment']) ? $options['comment'] : self::$comment;
+
         if ($curve instanceof Ed25519) {
             $key = Strings::packSSH2('ss', 'ssh-ed25519', $curve->encodePoint($publicKey));
 
@@ -197,7 +200,7 @@ abstract class OpenSSH extends Progenitor
                 return $key;
             }
 
-            $key = 'ssh-ed25519 ' . Base64::encode($key) . ' ' . self::$comment;
+            $key = 'ssh-ed25519 ' . Base64::encode($key) . ' ' . $comment;
             return $key;
         }
 
@@ -226,11 +229,11 @@ abstract class OpenSSH extends Progenitor
         $points = "\4" . $publicKey[0]->toBytes() . $publicKey[1]->toBytes();
         $key = Strings::packSSH2('sss', 'ecdsa-sha2-' . $alias, $alias, $points);
 
-        if (self::$binary) {
+        if (isset($options['binary']) ? $options['binary'] : self::$binary) {
             return $key;
         }
 
-        $key = 'ecdsa-sha2-' . $alias . ' ' . Base64::encode($key) . ' ' . self::$comment;
+        $key = 'ecdsa-sha2-' . $alias . ' ' . Base64::encode($key) . ' ' . $comment;
 
         return $key;
     }
diff --git a/phpseclib/Crypt/ECDSA/Keys/PKCS1.php b/phpseclib/Crypt/ECDSA/Keys/PKCS1.php
index aebc84eb..c9007b88 100644
--- a/phpseclib/Crypt/ECDSA/Keys/PKCS1.php
+++ b/phpseclib/Crypt/ECDSA/Keys/PKCS1.php
@@ -115,9 +115,10 @@ abstract class PKCS1 extends Progenitor
      * @param \phpseclib\Crypt\ECDSA\BaseCurves\Base $curve
      * @param \phpseclib\Math\Common\FiniteField\Integer[] $publicKey
      * @param string $password optional
+     * @param array $options optional
      * @return string
      */
-    public static function savePrivateKey(Integer $privateKey, BaseCurve $curve, array $publicKey, $password = '')
+    public static function savePrivateKey(Integer $privateKey, BaseCurve $curve, array $publicKey, $password = '', $options = [])
     {
         self::initialize_static_variables();
 
@@ -136,6 +137,6 @@ abstract class PKCS1 extends Progenitor
 
         $key = ASN1::encodeDER($key, Maps\ECPrivateKey::MAP);
 
-        return self::wrapPrivateKey($key, 'EC', $password);
+        return self::wrapPrivateKey($key, 'EC', $password, $options);
     }
 }
diff --git a/phpseclib/Crypt/ECDSA/Keys/PKCS8.php b/phpseclib/Crypt/ECDSA/Keys/PKCS8.php
index 3306e066..78b056f5 100644
--- a/phpseclib/Crypt/ECDSA/Keys/PKCS8.php
+++ b/phpseclib/Crypt/ECDSA/Keys/PKCS8.php
@@ -198,9 +198,10 @@ abstract class PKCS8 extends Progenitor
      * @param \phpseclib\Crypt\ECDSA\BaseCurves\Base $curve
      * @param \phpseclib\Math\Common\FiniteField\Integer[] $publicKey
      * @param string $password optional
+     * @param array $options optional
      * @return string
      */
-    public static function savePrivateKey(Integer $privateKey, BaseCurve $curve, array $publicKey, $password = '')
+    public static function savePrivateKey(Integer $privateKey, BaseCurve $curve, array $publicKey, $password = '', $options = [])
     {
         self::initialize_static_variables();
 
@@ -228,6 +229,6 @@ abstract class PKCS8 extends Progenitor
 
         $key = ASN1::encodeDER($key, Maps\ECPrivateKey::MAP);
 
-        return self::wrapPrivateKey($key, [], $params, $password, 'id-ecPublicKey');
+        return self::wrapPrivateKey($key, [], $params, $password, 'id-ecPublicKey', $options);
     }
 }
diff --git a/phpseclib/Crypt/ECDSA/Keys/PuTTY.php b/phpseclib/Crypt/ECDSA/Keys/PuTTY.php
index ce4eb563..eedcc8db 100644
--- a/phpseclib/Crypt/ECDSA/Keys/PuTTY.php
+++ b/phpseclib/Crypt/ECDSA/Keys/PuTTY.php
@@ -96,9 +96,10 @@ abstract class PuTTY extends Progenitor
      * @param \phpseclib\Crypt\ECDSA\BaseCurves\Base $curve
      * @param \phpseclib\Math\Common\FiniteField\Integer[] $publicKey
      * @param string $password optional
+     * @param array $options optional
      * @return string
      */
-    public static function savePrivateKey(Integer $privateKey, BaseCurve $curve, array $publicKey, $password = false)
+    public static function savePrivateKey(Integer $privateKey, BaseCurve $curve, array $publicKey, $password = false, $options = [])
     {
         self::initialize_static_variables();
 
@@ -121,7 +122,7 @@ abstract class PuTTY extends Progenitor
             Strings::packSSH2('s', $privateKey->secret) :
             Strings::packSSH2('s', $private);
 
-        return self::wrapPrivateKey($public, $private, $name, $password);
+        return self::wrapPrivateKey($public, $private, $name, $password, $options);
     }
 
     /**
diff --git a/phpseclib/Crypt/ECDSA/Parameters.php b/phpseclib/Crypt/ECDSA/Parameters.php
index 040633ca..03d30261 100644
--- a/phpseclib/Crypt/ECDSA/Parameters.php
+++ b/phpseclib/Crypt/ECDSA/Parameters.php
@@ -25,15 +25,16 @@ use phpseclib\Crypt\ECDSA;
 class Parameters extends ECDSA
 {
     /**
-     * Returns the public key
+     * Returns the parameters
      *
      * @param string $type
+     * @param array $options optional
      * @return string
      */
-    public function toString($type = 'PKCS1')
+    public function toString($type = 'PKCS1', $options = [])
     {
         $type = self::validatePlugin('Keys', 'PKCS1', 'saveParameters');
 
-        return $type::saveParameters($this->curve);
+        return $type::saveParameters($this->curve, $options);
     }
 }
diff --git a/phpseclib/Crypt/ECDSA/PrivateKey.php b/phpseclib/Crypt/ECDSA/PrivateKey.php
index f79dabdb..82fdf015 100644
--- a/phpseclib/Crypt/ECDSA/PrivateKey.php
+++ b/phpseclib/Crypt/ECDSA/PrivateKey.php
@@ -182,13 +182,14 @@ class PrivateKey extends ECDSA implements Common\PrivateKey
      * Returns the private key
      *
      * @param string $type
+     * @param array $options optional
      * @return string
      */
-    public function toString($type)
+    public function toString($type, $options = [])
     {
         $type = self::validatePlugin('Keys', $type, 'savePrivateKey');
 
-        return $type::savePrivateKey($this->dA, $this->curve, $this->QA, $this->password);
+        return $type::savePrivateKey($this->dA, $this->curve, $this->QA, $this->password, $options);
     }
 
     /**
diff --git a/phpseclib/Crypt/ECDSA/PublicKey.php b/phpseclib/Crypt/ECDSA/PublicKey.php
index ef09a97e..459c468f 100644
--- a/phpseclib/Crypt/ECDSA/PublicKey.php
+++ b/phpseclib/Crypt/ECDSA/PublicKey.php
@@ -159,12 +159,13 @@ class PublicKey extends ECDSA implements Common\PublicKey
      * Returns the public key
      *
      * @param string $type
+     * @param array $options optional
      * @return string
      */
-    public function toString($type)
+    public function toString($type, $options = [])
     {
         $type = self::validatePlugin('Keys', $type, 'savePublicKey');
 
-        return $type::savePublicKey($this->curve, $this->QA);
+        return $type::savePublicKey($this->curve, $this->QA, $options);
     }
 }
diff --git a/phpseclib/Crypt/RSA/Keys/OpenSSH.php b/phpseclib/Crypt/RSA/Keys/OpenSSH.php
index 77545d25..5df9696e 100644
--- a/phpseclib/Crypt/RSA/Keys/OpenSSH.php
+++ b/phpseclib/Crypt/RSA/Keys/OpenSSH.php
@@ -63,17 +63,19 @@ abstract class OpenSSH extends Progenitor
      * @access public
      * @param \phpseclib\Math\BigInteger $n
      * @param \phpseclib\Math\BigInteger $e
+     * @param array $options optional
      * @return string
      */
-    public static function savePublicKey(BigInteger $n, BigInteger $e)
+    public static function savePublicKey(BigInteger $n, BigInteger $e, $options = [])
     {
         $RSAPublicKey = Strings::packSSH2('sii', 'ssh-rsa', $e, $n);
 
-        if (self::$binary) {
+        if (isset($options['binary']) ? $options['binary'] : self::$binary) {
             return $RSAPublicKey;
         }
 
-        $RSAPublicKey = 'ssh-rsa ' . Base64::encode($RSAPublicKey) . ' ' . self::$comment;
+        $comment = isset($options['comment']) ? $options['comment'] : self::$comment;
+        $RSAPublicKey = 'ssh-rsa ' . Base64::encode($RSAPublicKey) . ' ' . $comment;
 
         return $RSAPublicKey;
     }
diff --git a/phpseclib/Crypt/RSA/Keys/PKCS1.php b/phpseclib/Crypt/RSA/Keys/PKCS1.php
index 6dbb46f4..e5152cc1 100644
--- a/phpseclib/Crypt/RSA/Keys/PKCS1.php
+++ b/phpseclib/Crypt/RSA/Keys/PKCS1.php
@@ -101,9 +101,10 @@ abstract class PKCS1 extends Progenitor
      * @param array $exponents
      * @param array $coefficients
      * @param string $password optional
+     * @param array $options optional
      * @return string
      */
-    public static function savePrivateKey(BigInteger $n, BigInteger $e, BigInteger $d, $primes, $exponents, $coefficients, $password = '')
+    public static function savePrivateKey(BigInteger $n, BigInteger $e, BigInteger $d, $primes, $exponents, $coefficients, $password = '', $options = [])
     {
         $num_primes = count($primes);
         $key = [
@@ -127,7 +128,7 @@ abstract class PKCS1 extends Progenitor
 
         $key = ASN1::encodeDER($key, Maps\RSAPrivateKey::MAP);
 
-        return self::wrapPrivateKey($key, 'RSA', $password);
+        return self::wrapPrivateKey($key, 'RSA', $password, $options);
     }
 
     /**
diff --git a/phpseclib/Crypt/RSA/Keys/PKCS8.php b/phpseclib/Crypt/RSA/Keys/PKCS8.php
index 7b998c97..1178e93d 100644
--- a/phpseclib/Crypt/RSA/Keys/PKCS8.php
+++ b/phpseclib/Crypt/RSA/Keys/PKCS8.php
@@ -104,13 +104,14 @@ abstract class PKCS8 extends Progenitor
      * @param array $exponents
      * @param array $coefficients
      * @param string $password optional
+     * @param array $options optional
      * @return string
      */
-    public static function savePrivateKey(BigInteger $n, BigInteger $e, BigInteger $d, $primes, $exponents, $coefficients, $password = '')
+    public static function savePrivateKey(BigInteger $n, BigInteger $e, BigInteger $d, $primes, $exponents, $coefficients, $password = '', $options = [])
     {
         $key = PKCS1::savePrivateKey($n, $e, $d, $primes, $exponents, $coefficients);
         $key = ASN1::extractBER($key);
-        return self::wrapPrivateKey($key, [], null, $password);
+        return self::wrapPrivateKey($key, [], null, $password, $options);
     }
 
     /**
@@ -119,9 +120,10 @@ abstract class PKCS8 extends Progenitor
      * @access public
      * @param \phpseclib\Math\BigInteger $n
      * @param \phpseclib\Math\BigInteger $e
+     * @param array $options optional
      * @return string
      */
-    public static function savePublicKey(BigInteger $n, BigInteger $e)
+    public static function savePublicKey(BigInteger $n, BigInteger $e, $options = [])
     {
         $key = PKCS1::savePublicKey($n, $e);
         $key = ASN1::extractBER($key);
diff --git a/phpseclib/Crypt/RSA/Keys/PuTTY.php b/phpseclib/Crypt/RSA/Keys/PuTTY.php
index ea8d61b5..0fa54704 100644
--- a/phpseclib/Crypt/RSA/Keys/PuTTY.php
+++ b/phpseclib/Crypt/RSA/Keys/PuTTY.php
@@ -100,9 +100,10 @@ abstract class PuTTY extends Progenitor
      * @param array $exponents
      * @param array $coefficients
      * @param string $password optional
+     * @param array $options optional
      * @return string
      */
-    public static function savePrivateKey(BigInteger $n, BigInteger $e, BigInteger $d, $primes, $exponents, $coefficients, $password = '')
+    public static function savePrivateKey(BigInteger $n, BigInteger $e, BigInteger $d, $primes, $exponents, $coefficients, $password = '', $options = [])
     {
         if (count($primes) != 2) {
             throw new \InvalidArgumentException('PuTTY does not support multi-prime RSA keys');
@@ -111,7 +112,7 @@ abstract class PuTTY extends Progenitor
         $public =  Strings::packSSH2('ii', $e, $n);
         $private = Strings::packSSH2('iiii', $d, $primes[1], $primes[2], $coefficients[2]);
 
-        return self::wrapPrivateKey($public, $private, 'ssh-rsa', $password);
+        return self::wrapPrivateKey($public, $private, 'ssh-rsa', $password, $options);
     }
 
     /**
diff --git a/phpseclib/Crypt/RSA/PrivateKey.php b/phpseclib/Crypt/RSA/PrivateKey.php
index 526fedf6..177ef9b9 100644
--- a/phpseclib/Crypt/RSA/PrivateKey.php
+++ b/phpseclib/Crypt/RSA/PrivateKey.php
@@ -514,9 +514,10 @@ class PrivateKey extends RSA implements Common\PrivateKey
      * Returns the private key
      *
      * @param string $type
+     * @param array $options optional
      * @return string
      */
-    public function toString($type)
+    public function toString($type, $options = [])
     {
         $type = self::validatePlugin(
             'Keys',
@@ -528,10 +529,10 @@ class PrivateKey extends RSA implements Common\PrivateKey
             return $type::savePublicKey($this->modulus, $this->exponent);
         }
 
-        return $type::savePrivateKey($this->modulus, $this->publicExponent, $this->exponent, $this->primes, $this->exponents, $this->coefficients, $this->password);
+        return $type::savePrivateKey($this->modulus, $this->publicExponent, $this->exponent, $this->primes, $this->exponents, $this->coefficients, $this->password, $options);
 
         /*
-        $key = $type::savePrivateKey($this->modulus, $this->publicExponent, $this->exponent, $this->primes, $this->exponents, $this->coefficients, $this->password);
+        $key = $type::savePrivateKey($this->modulus, $this->publicExponent, $this->exponent, $this->primes, $this->exponents, $this->coefficients, $this->password, $options);
         if ($key !== false || count($this->primes) == 2) {
             return $key;
         }
@@ -555,7 +556,7 @@ class PrivateKey extends RSA implements Common\PrivateKey
             $exponents[$i] = $this->modulus->modInverse($temp);
         }
 
-        return $type::savePrivateKey($this->modulus, $this->publicExponent, $this->exponent, $primes, $exponents, $coefficients, $this->password);
+        return $type::savePrivateKey($this->modulus, $this->publicExponent, $this->exponent, $primes, $exponents, $coefficients, $this->password, $options);
         */
     }
 }
diff --git a/phpseclib/Crypt/RSA/PublicKey.php b/phpseclib/Crypt/RSA/PublicKey.php
index f602c346..66cc091e 100644
--- a/phpseclib/Crypt/RSA/PublicKey.php
+++ b/phpseclib/Crypt/RSA/PublicKey.php
@@ -465,13 +465,14 @@ class PublicKey extends RSA implements Common\PublicKey
      * function won't return it since this library, for the most part, doesn't distinguish between public and private keys.
      *
      * @param string $type
+     * @param array $options optional
      * @return mixed
      */
-    public function toString($type)
+    public function toString($type, $options = [])
     {
         $type = self::validatePlugin('Keys', $type, 'savePublicKey');
 
-        return $type::savePublicKey($this->modulus, $this->publicExponent);
+        return $type::savePublicKey($this->modulus, $this->publicExponent, $options);
     }
 
     /**
diff --git a/phpseclib/Net/SSH2.php b/phpseclib/Net/SSH2.php
index bd1eaa66..be95a0af 100644
--- a/phpseclib/Net/SSH2.php
+++ b/phpseclib/Net/SSH2.php
@@ -2447,10 +2447,7 @@ class SSH2
             throw new UnsupportedAlgorithmException('Please use either an RSA key, an ECDSA one or a DSA key');
         }
 
-        $status = OpenSSH::getBinaryOutput();
-        OpenSSH::setBinaryOutput(true);
-        $publickeyStr = $publickey->toString('OpenSSH');
-        OpenSSH::setBinaryOutput($status);
+        $publickeyStr = $publickey->toString('OpenSSH', ['binary' => true]);
 
         $part1 = Strings::packSSH2(
             'Csss',