Merge pull request #2582 from alex/stdlib-pbkdf2hmac

Use the stdlib's PBKDF2 implementation when available.

django/utils/crypto.py

@@ -117,7 +117,24 @@ def _long_to_bin(x, hex_format_string):
     return binascii.unhexlify((hex_format_string % x).encode('ascii'))
 
 
-def pbkdf2(password, salt, iterations, dklen=0, digest=None):
+if hasattr(hashlib, "pbkdf2_hmac"):
+    def pbkdf2(password, salt, iterations, dklen=0, digest=None):
+        """
+        Implements PBKDF2 with the same API as Django's existing
+        implementation, using the stdlib.
+
+        This is used in Python 3.4 and up.
+        """
+        if digest is None:
+            digest = hashlib.sha256
+        if not dklen:
+            dklen = None
+        password = force_bytes(password)
+        salt = force_bytes(salt)
+        return hashlib.pbkdf2_hmac(
+            digest().name, password, salt, iterations, dklen)
+else:
+    def pbkdf2(password, salt, iterations, dklen=0, digest=None):
         """
         Implements PBKDF2 as defined in RFC 2898, section 5.2