diff --git a/phpseclib/Crypt/Blowfish.php b/phpseclib/Crypt/Blowfish.php
index 3a94a743..54d28593 100644
--- a/phpseclib/Crypt/Blowfish.php
+++ b/phpseclib/Crypt/Blowfish.php
@@ -288,7 +288,7 @@ class Blowfish extends BlockCipher
     /**
      * Default Constructor.
      *
-     * @param int|string $mode
+     * @param string $mode
      * @access public
      * @throws \InvalidArgumentException if an invalid / unsupported mode is provided
      */
@@ -296,7 +296,7 @@ class Blowfish extends BlockCipher
     {
         parent::__construct($mode);
 
-        if ($mode == self::MODE_STREAM) {
+        if ($this->mode == self::MODE_STREAM) {
             throw new \InvalidArgumentException('Block ciphers cannot be ran in stream mode');
         }
     }
diff --git a/phpseclib/Crypt/Common/SymmetricKey.php b/phpseclib/Crypt/Common/SymmetricKey.php
index 80de0fc2..28041d3d 100644
--- a/phpseclib/Crypt/Common/SymmetricKey.php
+++ b/phpseclib/Crypt/Common/SymmetricKey.php
@@ -602,23 +602,21 @@ abstract class SymmetricKey
      *
      * - gcm
      *
-     * @param string|int $mode
+     * @param string $mode
      * @access public
      * @throws BadModeException if an invalid / unsupported mode is provided
      */
     public function __construct($mode)
     {
-        if (!is_int($mode) || !in_array($mode, self::MODE_MAP, true)) {
-            $mode = strtolower($mode);
-            // necessary because of 5.6 compatibility; we can't do isset(self::MODE_MAP[$mode]) in 5.6
-            $map = self::MODE_MAP;
-            if (!isset($map[$mode])) {
-                throw new BadModeException('No valid mode has been specified');
-            }
-
-            $mode = self::MODE_MAP[$mode];
+        $mode = strtolower($mode);
+        // necessary because of 5.6 compatibility; we can't do isset(self::MODE_MAP[$mode]) in 5.6
+        $map = self::MODE_MAP;
+        if (!isset($map[$mode])) {
+            throw new BadModeException('No valid mode has been specified');
         }
 
+        $mode = self::MODE_MAP[$mode];
+
         // $mode dependent settings
         switch ($mode) {
             case self::MODE_ECB:
diff --git a/phpseclib/Crypt/DES.php b/phpseclib/Crypt/DES.php
index 2a55a276..40c0f947 100644
--- a/phpseclib/Crypt/DES.php
+++ b/phpseclib/Crypt/DES.php
@@ -584,7 +584,7 @@ class DES extends BlockCipher
     /**
      * Default Constructor.
      *
-     * @param int|string $mode
+     * @param string $mode
      * @access public
      * @throws BadModeException if an invalid / unsupported mode is provided
      */
@@ -592,7 +592,7 @@ class DES extends BlockCipher
     {
         parent::__construct($mode);
 
-        if ($mode == self::MODE_STREAM) {
+        if ($this->mode == self::MODE_STREAM) {
             throw new BadModeException('Block ciphers cannot be ran in stream mode');
         }
     }
diff --git a/phpseclib/Crypt/RC2.php b/phpseclib/Crypt/RC2.php
index 425532bc..317d4380 100644
--- a/phpseclib/Crypt/RC2.php
+++ b/phpseclib/Crypt/RC2.php
@@ -265,7 +265,7 @@ class RC2 extends BlockCipher
     /**
      * Default Constructor.
      *
-     * @param int|string $mode
+     * @param string $mode
      * @access public
      * @throws \InvalidArgumentException if an invalid / unsupported mode is provided
      */
@@ -273,7 +273,7 @@ class RC2 extends BlockCipher
     {
         parent::__construct($mode);
 
-        if ($mode == self::MODE_STREAM) {
+        if ($this->mode == self::MODE_STREAM) {
             throw new BadModeException('Block ciphers cannot be ran in stream mode');
         }
     }
diff --git a/phpseclib/Crypt/Rijndael.php b/phpseclib/Crypt/Rijndael.php
index 0483bf8b..58aa80e0 100644
--- a/phpseclib/Crypt/Rijndael.php
+++ b/phpseclib/Crypt/Rijndael.php
@@ -168,7 +168,7 @@ class Rijndael extends BlockCipher
     /**
      * Default Constructor.
      *
-     * @param int|string $mode
+     * @param string $mode
      * @access public
      * @throws \InvalidArgumentException if an invalid / unsupported mode is provided
      */
@@ -176,7 +176,7 @@ class Rijndael extends BlockCipher
     {
         parent::__construct($mode);
 
-        if ($mode == self::MODE_STREAM) {
+        if ($this->mode == self::MODE_STREAM) {
             throw new BadModeException('Block ciphers cannot be ran in stream mode');
         }
     }
diff --git a/phpseclib/Crypt/TripleDES.php b/phpseclib/Crypt/TripleDES.php
index 32c3c9ca..aa1f5216 100644
--- a/phpseclib/Crypt/TripleDES.php
+++ b/phpseclib/Crypt/TripleDES.php
@@ -138,7 +138,7 @@ class TripleDES extends DES
      *
      * @see \phpseclib\Crypt\DES::__construct()
      * @see \phpseclib\Crypt\Common\SymmetricKey::__construct()
-     * @param int|string $mode
+     * @param string $mode
      * @access public
      */
     public function __construct($mode)
@@ -147,7 +147,6 @@ class TripleDES extends DES
             // In case of self::MODE_3CBC, we init as CRYPT_DES_MODE_CBC
             // and additional flag us internally as 3CBC
             case '3cbc':
-                $mode = self::MODE_3CBC;
                 parent::__construct('cbc');
                 $this->mode_3cbc = true;
 
@@ -168,6 +167,10 @@ class TripleDES extends DES
             // If not 3CBC, we init as usual
             default:
                 parent::__construct($mode);
+
+                if ($this->mode == self::MODE_STREAM) {
+                    throw new BadModeException('Block ciphers cannot be ran in stream mode');
+                }
         }
     }
 
diff --git a/phpseclib/Crypt/Twofish.php b/phpseclib/Crypt/Twofish.php
index 32d7c000..f9f1dce3 100644
--- a/phpseclib/Crypt/Twofish.php
+++ b/phpseclib/Crypt/Twofish.php
@@ -374,7 +374,7 @@ class Twofish extends BlockCipher
     /**
      * Default Constructor.
      *
-     * @param int|string $mode
+     * @param string $mode
      * @access public
      * @throws BadModeException if an invalid / unsupported mode is provided
      */
@@ -382,7 +382,7 @@ class Twofish extends BlockCipher
     {
         parent::__construct($mode);
 
-        if ($mode == self::MODE_STREAM) {
+        if ($this->mode == self::MODE_STREAM) {
             throw new BadModeException('Block ciphers cannot be ran in stream mode');
         }
     }