add passlib for sha-512 salted hash generation

passlib/handlers/postgres.py

@@ -0,0 +1,57 @@
+"""passlib.handlers.postgres_md5 - MD5-based algorithm used by Postgres for pg_shadow table"""
+#=============================================================================
+# imports
+#=============================================================================
+# core
+from hashlib import md5
+import re
+import logging; log = logging.getLogger(__name__)
+from warnings import warn
+# site
+# pkg
+from passlib.utils import to_bytes
+from passlib.utils.compat import b, bytes, str_to_uascii, unicode, u
+import passlib.utils.handlers as uh
+# local
+__all__ = [
+    "postgres_md5",
+]
+
+#=============================================================================
+# handler
+#=============================================================================
+class postgres_md5(uh.HasUserContext, uh.StaticHandler):
+    """This class implements the Postgres MD5 Password hash, and follows the :ref:`password-hash-api`.
+
+    It does a single round of hashing, and relies on the username as the salt.
+
+    The :meth:`~passlib.ifc.PasswordHash.encrypt`, :meth:`~passlib.ifc.PasswordHash.genhash`, and :meth:`~passlib.ifc.PasswordHash.verify` methods all require the
+    following additional contextual keywords:
+
+    :type user: str
+    :param user: name of postgres user account this password is associated with.
+    """
+    #===================================================================
+    # algorithm information
+    #===================================================================
+    name = "postgres_md5"
+    _hash_prefix = u("md5")
+    checksum_chars = uh.HEX_CHARS
+    checksum_size = 32
+
+    #===================================================================
+    # primary interface
+    #===================================================================
+    def _calc_checksum(self, secret):
+        if isinstance(secret, unicode):
+            secret = secret.encode("utf-8")
+        user = to_bytes(self.user, "utf-8", param="user")
+        return str_to_uascii(md5(secret + user).hexdigest())
+
+    #===================================================================
+    # eoc
+    #===================================================================
+
+#=============================================================================
+# eof
+#=============================================================================