def encrypt_block(self, plaintext):
"""Return 8-word ciphertext, encrypted from plaintext.
`plaintext` must be a list of 8 64-bit words.
"""
key = self.key
tweak = self.tweak
state = words(list(imap(add64, plaintext, key[:8])))
state[5] = add64(state[5], tweak[0])
state[6] = add64(state[6], tweak[1])
for r, s in izip(xrange(1, 19), cycle((0, 16))):
for i in xrange(16):
m, n = PERM[i]
state[m] = add64(state[m], state[n])
state[n] = RotL_64(state[n], ROT[i + s])
state[n] = state[n] ^ state[m]
for y in xrange(8):
state[y] = add64(state[y], key[(r + y) % 9])
state[5] = add64(state[5], tweak[r % 3])
state[6] = add64(state[6], tweak[(r + 1) % 3])
state[7] = add64(state[7], r)
return state
def encrypt_block(self, plaintext):
"""Return 8-word ciphertext, encrypted from plaintext.
`plaintext` must be a list of 8 64-bit words.
"""
key = self.key
tweak = self.tweak
state = words(list(imap(add64, plaintext, key[:8])))
state[5] = add64(state[5], tweak[0])
state[6] = add64(state[6], tweak[1])
for r,s in izip(xrange(1,19),cycle((0,16))):
for i in xrange(16):
m,n = PERM[i]
state[m] = add64(state[m], state[n])
state[n] = RotL_64(state[n], ROT[i+s])
state[n] = state[n] ^ state[m]
for y in xrange(8):
state[y] = add64(state[y], key[(r+y) % 9])
state[5] = add64(state[5], tweak[r % 3])
state[6] = add64(state[6], tweak[(r+1) % 3])
state[7] = add64(state[7], r)
return state
def decrypt_block(self, ciphertext):
"""Return 8-word plaintext, decrypted from plaintext.
`ciphertext` must be a list of 8 64-bit words.
"""
key = self.key
tweak = self.tweak
state = ciphertext[:]
for r, s in izip(xrange(18, 0, -1), cycle((16, 0))):
for y in xrange(8):
state[y] = sub64(state[y], key[(r + y) % 9])
state[5] = sub64(state[5], tweak[r % 3])
state[6] = sub64(state[6], tweak[(r + 1) % 3])
state[7] = sub64(state[7], r)
for i in xrange(15, -1, -1):
m, n = PERM[i]
state[n] = RotR_64(state[m] ^ state[n], ROT[i + s])
state[m] = sub64(state[m], state[n])
result = list(imap(sub64, state, key))
result[5] = sub64(result[5], tweak[0])
result[6] = sub64(result[6], tweak[1])
return result
def decrypt_block(self, ciphertext):
"""Return 8-word plaintext, decrypted from plaintext.
`ciphertext` must be a list of 8 64-bit words.
"""
key = self.key
tweak = self.tweak
state = ciphertext[:]
for r,s in izip(xrange(18,0,-1),cycle((16,0))):
for y in xrange(8):
state[y] = sub64(state[y], key[(r+y) % 9])
state[5] = sub64(state[5], tweak[r % 3])
state[6] = sub64(state[6], tweak[(r+1) % 3])
state[7] = sub64(state[7], r)
for i in xrange(15,-1,-1):
m,n = PERM[i]
state[n] = RotR_64(state[m] ^ state[n], ROT[i+s])
state[m] = sub64(state[m], state[n])
result = list(imap(sub64, state, key))
result[5] = sub64(result[5], tweak[0])
result[6] = sub64(result[6], tweak[1])
return result