Added support for RSASSA_PSS (sha256-rsa-MGF1)

composer.json

@@ -16,6 +16,7 @@
   },
   "require": {
     "php": ">= 5.4",
-    "ext-openssl": "*"
+    "ext-openssl": "*",
+    "phpseclib/phpseclib": "^3.0"
   }
 }

src/XMLSecurityKey.php

@@ -3,6 +3,8 @@
 
 use DOMElement;
 use Exception;
+use phpseclib3\Crypt\PublicKeyLoader;
+use phpseclib3\Crypt\RSA;
 
 /**
  * xmlseclibs.php
@@ -62,6 +64,7 @@ class XMLSecurityKey
     const RSA_SHA384 = 'http://www.w3.org/2001/04/xmldsig-more#rsa-sha384';
     const RSA_SHA512 = 'http://www.w3.org/2001/04/xmldsig-more#rsa-sha512';
     const HMAC_SHA1 = 'http://www.w3.org/2000/09/xmldsig#hmac-sha1';
+    const RSASSA_PSS = 'http://www.w3.org/2007/05/xmldsig-more#sha256-rsa-MGF1';
     const AUTHTAG_LENGTH = 16;
 
     /** @var array */
@@ -73,6 +76,9 @@ class XMLSecurityKey
     /** @var mixed|null */
     public $key = null;
 
+    /** @var RSA|null */
+    public $rsaPrivateKey = null;
+
     /** @var string  */
     public $passphrase = "";
 
@@ -257,6 +263,10 @@ public function __construct($type, $params=null)
                 $this->cryptParams['library'] = $type;
                 $this->cryptParams['method'] = 'http://www.w3.org/2000/09/xmldsig#hmac-sha1';
                 break;
+            case (self::RSASSA_PSS):
+                $this->cryptParams['library'] = $type;
+                $this->cryptParams['method'] = 'http://www.w3.org/2007/05/xmldsig-more#sha256-rsa-MGF1';
+                break;
             default:
                 throw new Exception('Invalid Key Type');
         }
@@ -291,9 +301,9 @@ public function generateSessionKey()
             throw new Exception('Unknown key size for type "' . $this->type . '".');
         }
         $keysize = $this->cryptParams['keysize'];
-        
+
         $key = openssl_random_pseudo_bytes($keysize);
-        
+
         if ($this->type === self::TRIPLEDES_CBC) {
             /* Make sure that the generated key has the proper parity bits set.
              * Mcrypt doesn't care about the parity bits, but others may care.
@@ -308,7 +318,7 @@ public function generateSessionKey()
                 $key[$i] = chr($byte);
             }
         }
-        
+
         $this->key = $key;
         return $key;
     }
@@ -358,6 +368,13 @@ public function loadKey($key, $isFile=false, $isCert = false)
     {
         if ($isFile) {
             $this->key = file_get_contents($key);
+
+            if ($this->cryptParams['library'] == self::RSASSA_PSS) {
+                $this->rsaPrivateKey = PublicKeyLoader::loadPrivateKey(file_get_contents($key));
+                $this->rsaPrivateKey->withPadding(RSA::SIGNATURE_PSS);
+                $this->rsaPrivateKey->withHash('sha256');
+                $this->rsaPrivateKey->withMGFHash('sha256');
+            }
         } else {
             $this->key = $key;
         }
@@ -452,7 +469,7 @@ private function encryptSymmetric($data)
             $data = $this->padISO10126($data, $this->cryptParams['blocksize']);
             $encrypted = openssl_encrypt($data, $this->cryptParams['cipher'], $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->iv);
         }
-        
+
         if (false === $encrypted) {
             throw new Exception('Failure encrypting Data (openssl symmetric) - ' . openssl_error_string());
         }
@@ -483,7 +500,7 @@ private function decryptSymmetric($data)
         } else {
             $decrypted = openssl_decrypt($data, $this->cryptParams['cipher'], $this->key, OPENSSL_RAW_DATA | OPENSSL_ZERO_PADDING, $this->iv);
         }
-        
+
         if (false === $decrypted) {
             throw new Exception('Failure decrypting Data (openssl symmetric) - ' . openssl_error_string());
         }
@@ -647,6 +664,8 @@ public function signData($data)
                 return $this->signOpenSSL($data);
             case (self::HMAC_SHA1):
                 return hash_hmac("sha1", $data, $this->key, true);
+            case (self::RSASSA_PSS):
+                return $this->rsaPrivateKey->sign($data);
         }
     }
 
@@ -674,6 +693,8 @@ public function verifySignature($data, $signature)
             case (self::HMAC_SHA1):
                 $expectedSignature = hash_hmac("sha1", $data, $this->key, true);
                 return strcmp($signature, $expectedSignature) == 0;
+            case (self::RSASSA_PSS):
+                return $this->rsaPrivateKey->verify($data, $signature);
         }
     }