crypto modules

Cryptography/Hash_Functions/MD5/md5.py

@@ -0,0 +1,84 @@
+# MD5 Python 2 implementation
+# Copyright (C) 2013  Filippo Valsorda
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# Originally based, even if no code survives, on a Python license work
+# by Dinu C. Gherman (C) 2001 and Aurelian Coman
+# http://starship.python.net/crew/gherman/programs/md5py/md5py.py
+
+import struct
+import binascii
+import math
+
+lrot = lambda x, n: (x << n) | (x >> (32 - n))
+
+
+class MD5():
+
+    A, B, C, D = (0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476)
+
+    # r specifies the per-round shift amounts
+    r = [7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22,
+         5,  9, 14, 20, 5,  9, 14, 20, 5,  9, 14, 20, 5,  9, 14, 20,
+         4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23,
+         6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21]
+
+    # Use binary integer part of the sines of integers (Radians) as constants
+    k = [int(math.floor(abs(math.sin(i + 1)) * (2 ** 32))) for i in range(64)]
+
+    def __init__(self, message):
+        length = struct.pack('<Q', len(message) * 8)
+        while len(message) > 64:
+            self._handle(message[:64])
+            message = message[64:]
+        message += '\x80'
+        message += '\x00' * ((56 - len(message) % 64) % 64)
+        message += length
+        while len(message):
+            self._handle(message[:64])
+            message = message[64:]
+
+    def _handle(self, chunk):
+        w = list(struct.unpack('<' + 'I' * 16, chunk))
+
+        a, b, c, d = self.A, self.B, self.C, self.D
+
+        for i in range(64):
+            if i < 16:
+                f = (b & c) | ((~b) & d)
+                g = i
+            elif i < 32:
+                f = (d & b) | ((~d) & c)
+                g = (5 * i + 1) % 16
+            elif i < 48:
+                f = b ^ c ^ d
+                g = (3 * i + 5) % 16
+            else:
+                f = c ^ (b | (~d))
+                g = (7 * i) % 16
+
+            x = b + lrot((a + f + self.k[i] + w[g]) & 0xffffffff, self.r[i])
+            a, b, c, d = d, x & 0xffffffff, b, c
+
+        self.A = (self.A + a) & 0xffffffff
+        self.B = (self.B + b) & 0xffffffff
+        self.C = (self.C + c) & 0xffffffff
+        self.D = (self.D + d) & 0xffffffff
+
+    def digest(self):
+        return struct.pack('<IIII', self.A, self.B, self.C, self.D)
+
+    def hexdigest(self):
+        return binascii.hexlify(self.digest()).decode()