crypto modules

Cryptography/Hash_Functions/MD5/MD4/md4.py

@@ -0,0 +1,95 @@
+# MD4 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 LGPL work by
+# Dmitry Rozmanov <dima@xenon.spb.ru> 2002
+# http://www.geocities.com/rozmanov/python/
+
+import struct
+import binascii
+
+lrot = lambda x, n: (x << n) | (x >> (32 - n))
+
+
+class MD4():
+
+    A, B, C, D = (0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476)
+    buf = [0x00] * 64
+
+    _F = lambda self, x, y, z: ((x & y) | (~x & z))
+    _G = lambda self, x, y, z: ((x & y) | (x & z) | (y & z))
+    _H = lambda self, x, y, z: (x ^ y ^ z)
+
+    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):
+        X = list(struct.unpack('<' + 'I' * 16, chunk))
+        A, B, C, D = self.A, self.B, self.C, self.D
+
+        for i in range(16):
+            k = i
+            if i % 4 == 0:
+                A = lrot((A + self._F(B, C, D) + X[k]) & 0xffffffff, 3)
+            elif i % 4 == 1:
+                D = lrot((D + self._F(A, B, C) + X[k]) & 0xffffffff, 7)
+            elif i % 4 == 2:
+                C = lrot((C + self._F(D, A, B) + X[k]) & 0xffffffff, 11)
+            elif i % 4 == 3:
+                B = lrot((B + self._F(C, D, A) + X[k]) & 0xffffffff, 19)
+
+        for i in range(16):
+            k = (i // 4) + (i % 4) * 4
+            if i % 4 == 0:
+                A = lrot((A + self._G(B, C, D) + X[k] + 0x5a827999) & 0xffffffff, 3)
+            elif i % 4 == 1:
+                D = lrot((D + self._G(A, B, C) + X[k] + 0x5a827999) & 0xffffffff, 5)
+            elif i % 4 == 2:
+                C = lrot((C + self._G(D, A, B) + X[k] + 0x5a827999) & 0xffffffff, 9)
+            elif i % 4 == 3:
+                B = lrot((B + self._G(C, D, A) + X[k] + 0x5a827999) & 0xffffffff, 13)
+
+        order = [0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15]
+        for i in range(16):
+            k = order[i]
+            if i % 4 == 0:
+                A = lrot((A + self._H(B, C, D) + X[k] + 0x6ed9eba1) & 0xffffffff, 3)
+            elif i % 4 == 1:
+                D = lrot((D + self._H(A, B, C) + X[k] + 0x6ed9eba1) & 0xffffffff, 9)
+            elif i % 4 == 2:
+                C = lrot((C + self._H(D, A, B) + X[k] + 0x6ed9eba1) & 0xffffffff, 11)
+            elif i % 4 == 3:
+                B = lrot((B + self._H(C, D, A) + X[k] + 0x6ed9eba1) & 0xffffffff, 15)
+
+        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()