# Python PRIDE implementation # Version: 1.0 # Date: 22/04/2015 # # ============================================================================= # Copyright (c) 2015 Camil Staps (info@camilstaps.nl) # ============================================================================= class Pride: def __init__(self,key): """Create a PRIDE cipher object key: the key as a 128-bit rawstring """ if len(key) * 8 == 128: self.key_whitening = string2number(key[:8]) self.key_1 = key[8:] else: raise ValueError, "Key must be a 128-bit rawstring" def encrypt(self,block): """Encrypt 1 block (8 bytes) Input: plaintext block as raw string Output: ciphertext block as raw string """ state = string2number(block) state = pLayer_dec(state) state = addRoundKey(state, self.key_whitening) for i in xrange (1,20): state = addRoundKey(state, pLayer_dec(roundKey(self.key_1, i))) state = sBoxLayer(state) state = lLayer(state) state = addRoundKey(state, pLayer_dec(roundKey(self.key_1, 20))) state = sBoxLayer(state) state = addRoundKey(state, self.key_whitening) state = pLayer(state) return number2string_N(state,8) # 0 1 2 3 4 5 6 7 8 9 a b c d e f Sbox= [0x0,0x4,0x8,0xf,0x1,0x5,0xe,0x9,0x2,0x7,0xa,0xc,0xb,0xd,0x6,0x3] Sbox_inv = [Sbox.index(x) for x in xrange(16)] PBox = [0,16,32,48,1,17,33,49,2,18,34,50,3,19,35,51,4,20,36,52,5,21,37,53,6,22,38,54,7,23,39,55,8,24,40,56,9,25,41,57,10,26,42,58,11,27,43,59,12,28,44,60,13,29,45,61,14,30,46,62,15,31,47,63] PBox_inv = [PBox.index(x) for x in xrange(64)] L0 = [[0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0], [0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0], [0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0], [0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1], [1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0], [0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0], [0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0], [0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1], [1,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0], [0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,0], [0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0], [0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1], [1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0], [0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0], [0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0], [0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0]] L0_inv = L0 L1 = [[1,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0], [0,1,1,0,0,0,0,0,0,0,0,0,1,0,0,0], [0,0,1,1,0,0,0,0,0,0,0,0,0,1,0,0], [0,0,0,1,1,0,0,0,0,0,0,0,0,0,1,0], [0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,1], [0,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0], [0,0,0,0,0,0,1,1,0,1,0,0,0,0,0,0], [1,0,0,0,0,0,0,1,0,0,1,0,0,0,0,0], [1,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0], [0,1,0,0,0,0,0,0,0,0,0,0,1,1,0,0], [0,0,1,0,0,0,0,0,0,0,0,0,0,1,1,0], [0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,1], [0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,1], [0,0,0,0,0,1,0,0,1,1,0,0,0,0,0,0], [0,0,0,0,0,0,1,0,0,1,1,0,0,0,0,0], [0,0,0,0,0,0,0,1,0,0,1,1,0,0,0,0]] L1_inv = [[0,0,0,0,0,0,1,1,0,0,0,0,0,0,1,0], [1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1], [1,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0], [0,1,1,0,0,0,0,0,0,1,0,0,0,0,0,0], [0,0,1,1,0,0,0,0,0,0,1,0,0,0,0,0], [0,0,0,1,1,0,0,0,0,0,0,1,0,0,0,0], [0,0,0,0,1,1,0,0,0,0,0,0,1,0,0,0], [0,0,0,0,0,1,1,0,0,0,0,0,0,1,0,0], [0,0,0,1,0,0,0,0,0,0,0,1,1,0,0,0], [0,0,0,0,1,0,0,0,0,0,0,0,1,1,0,0], [0,0,0,0,0,1,0,0,0,0,0,0,0,1,1,0], [0,0,0,0,0,0,1,0,0,0,0,0,0,0,1,1], [0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,1], [1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0], [0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0], [0,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0]] L2 = [[0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,1], [0,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0], [0,0,0,0,0,0,1,1,0,1,0,0,0,0,0,0], [1,0,0,0,0,0,0,1,0,0,1,0,0,0,0,0], [1,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0], [0,1,1,0,0,0,0,0,0,0,0,0,1,0,0,0], [0,0,1,1,0,0,0,0,0,0,0,0,0,1,0,0], [0,0,0,1,1,0,0,0,0,0,0,0,0,0,1,0], [0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,1], [0,0,0,0,0,1,0,0,1,1,0,0,0,0,0,0], [0,0,0,0,0,0,1,0,0,1,1,0,0,0,0,0], [0,0,0,0,0,0,0,1,0,0,1,1,0,0,0,0], [1,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0], [0,1,0,0,0,0,0,0,0,0,0,0,1,1,0,0], [0,0,1,0,0,0,0,0,0,0,0,0,0,1,1,0], [0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,1]] L2_inv = [[0,0,1,1,0,0,0,0,0,0,1,0,0,0,0,0], [0,0,0,1,1,0,0,0,0,0,0,1,0,0,0,0], [0,0,0,0,1,1,0,0,0,0,0,0,1,0,0,0], [0,0,0,0,0,1,1,0,0,0,0,0,0,1,0,0], [0,0,0,0,0,0,1,1,0,0,0,0,0,0,1,0], [1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1], [1,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0], [0,1,1,0,0,0,0,0,0,1,0,0,0,0,0,0], [0,0,0,0,0,0,0,1,1,0,0,0,0,0,0,1], [1,0,0,0,0,0,0,0,1,1,0,0,0,0,0,0], [0,1,0,0,0,0,0,0,0,1,1,0,0,0,0,0], [0,0,1,0,0,0,0,0,0,0,1,1,0,0,0,0], [0,0,0,1,0,0,0,0,0,0,0,1,1,0,0,0], [0,0,0,0,1,0,0,0,0,0,0,0,1,1,0,0], [0,0,0,0,0,1,0,0,0,0,0,0,0,1,1,0], [0,0,0,0,0,0,1,0,0,0,0,0,0,0,1,1]] L3 = [[1,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0], [0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,0], [0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0], [0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1], [1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0], [0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0], [0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0], [0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0], [0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0], [0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0], [0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0], [0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1], [1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0], [0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0], [0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0], [0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1]] L3_inv = L3 def matrixMultiply(matrix, input): """Multiply a vector with a binary matrix Input: matrix as [[Int]]; input as Int Output: Int""" mult = [ reduce( lambda a,b: a^b, [c * ((input >> (15 - c_i)) & 0x1) for c_i, c in reversed(list(enumerate(r)))], 0 ) for r in matrix ] return sum([(1 << (15-i)) * v for i,v in enumerate(mult)]) def roundKey(key, i): """Calculate a round key Input: the base key (second half of it) as a rawstring; the round number Output: the round key as rawstring""" return string2number( key[0] + chr((ord(key[1]) + 193 * i) % 256) + key[2] + chr((ord(key[3]) + 165 * i) % 256) + key[4] + chr((ord(key[5]) + 81 * i) % 256) + key[6] + chr((ord(key[7]) + 197 * i) % 256) ) def addRoundKey(state,roundkey): return state ^ roundkey def sBoxLayer(state): """SBox function for encryption Input: 64-bit integer Output: 64-bit integer""" return sum([Sbox[( state >> (i*4)) & 0xF] << (i*4) for i in xrange(16)]) def sBoxLayer_dec(state): """Inverse SBox function for decryption Input: 64-bit integer Output: 64-bit integer""" return sum([Sbox_inv[( state >> (i*4)) & 0xF] << (i*4) for i in xrange(16)]) def pLayer(state): """Permutation layer for encryption Input: 64-bit integer Output: 64-bit integer""" return sum ([((state >> i) & 0x01) << PBox[i] for i in xrange(64)]) def pLayer_dec(state): """Permutation layer for decryption Input: 64-bit integer Output: 64-bit integer""" return sum ([((state >> i) & 0x01) << PBox_inv[i] for i in xrange(64)]) def lLayer(state): """Perform the L layer: * P (permutation) * L0 .. L3 on all four 16-bit substrings * P_inv (permutation inverse) Input: the current state, as an 8-byte rawstring Output: the new state, as an 8-byte rawstring""" state = pLayer(state) state = (matrixMultiply(L0, (state >> 48) & 0xffff) << 48) + ( matrixMultiply(L1, (state >> 32) & 0xffff) << 32) + ( matrixMultiply(L2, (state >> 16) & 0xffff) << 16) + ( matrixMultiply(L3, state & 0xffff)) state = pLayer_dec(state) return state def string2number(i): """ Convert a string to a number Input: string (big-endian) Output: long or integer """ return int(i.encode('hex'),16) def number2string_N(i, N): """Convert a number to a string of fixed size i: long or integer N: length of string Output: string (big-endian) """ s = '%0*x' % (N*2, i) return s.decode('hex') def _test(): import doctest doctest.testmod() if __name__ == "__main__": print Pride("0000000000000000fedcba9876543210".decode('hex')).encrypt("0123456789abcdef".decode('hex')).encode('hex')