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# -*- coding: utf-8 -*-
#
# SelfTest/Hash/common.py: Common code for Crypto.SelfTest.Hash
#
# Written in 2008 by Dwayne C. Litzenberger <dlitz@dlitz.net>
#
# ===================================================================
# The contents of this file are dedicated to the public domain. To
# the extent that dedication to the public domain is not available,
# everyone is granted a worldwide, perpetual, royalty-free,
# non-exclusive license to exercise all rights associated with the
# contents of this file for any purpose whatsoever.
# No rights are reserved.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
# ===================================================================
"""Self-testing for PyCrypto hash modules"""
__revision__ = "$Id$"
import sys
import unittest
from binascii import a2b_hex, b2a_hex
# For compatibility with Python 2.1 and Python 2.2
if sys.hexversion < 0x02030000:
# Python 2.1 doesn't have a dict() function
# Python 2.2 dict() function raises TypeError if you do dict(MD5='blah')
def dict(**kwargs):
return kwargs.copy()
else:
dict = __builtins__['dict']
class _NoDefault: pass # sentinel object
def _extract(d, k, default=_NoDefault):
"""Get an item from a dictionary, and remove it from the dictionary."""
try:
retval = d[k]
except KeyError:
if default is _NoDefault:
raise
return default
del d[k]
return retval
# Generic cipher test case
class CipherSelfTest(unittest.TestCase):
def __init__(self, module, params):
unittest.TestCase.__init__(self)
self.module = module
# Extract the parameters
params = params.copy()
self.description = _extract(params, 'description')
self.key = _extract(params, 'key')
self.plaintext = _extract(params, 'plaintext')
self.ciphertext = _extract(params, 'ciphertext')
self.module_name = _extract(params, 'module_name', None)
mode = _extract(params, 'mode', None)
self.mode_name = str(mode)
if mode is not None:
# Block cipher
self.mode = getattr(self.module, "MODE_" + mode)
self.iv = _extract(params, 'iv', None)
else:
# Stream cipher
self.mode = None
self.iv = None
self.extra_params = params
def shortDescription(self):
return self.description
def _new(self):
params = self.extra_params.copy()
# Handle CTR mode parameters. By default, we use Counter.new(self.module.block_size)
if hasattr(self.module, "MODE_CTR") and self.mode == self.module.MODE_CTR:
from Crypto.Util import Counter
ctr_class = _extract(params, 'ctr_class', Counter.new)
ctr_params = _extract(params, 'ctr_params', {}).copy()
if ctr_params.has_key('prefix'): ctr_params['prefix'] = a2b_hex(ctr_params['prefix'])
if ctr_params.has_key('suffix'): ctr_params['suffix'] = a2b_hex(ctr_params['suffix'])
if not ctr_params.has_key('nbits'):
ctr_params['nbits'] = 8*(self.module.block_size - len(ctr_params.get('prefix', '')) - len(ctr_params.get('suffix', '')))
params['counter'] = ctr_class(**ctr_params)
if self.mode is None:
# Stream cipher
return self.module.new(a2b_hex(self.key), **params)
elif self.iv is None:
# Block cipher without iv
return self.module.new(a2b_hex(self.key), self.mode, **params)
else:
# Block cipher with iv
return self.module.new(a2b_hex(self.key), self.mode, a2b_hex(self.iv), **params)
def runTest(self):
plaintext = a2b_hex(self.plaintext)
ciphertext = a2b_hex(self.ciphertext)
ct1 = b2a_hex(self._new().encrypt(plaintext))
pt1 = b2a_hex(self._new().decrypt(ciphertext))
ct2 = b2a_hex(self._new().encrypt(plaintext))
pt2 = b2a_hex(self._new().decrypt(ciphertext))
self.assertEqual(self.ciphertext, ct1) # encrypt
self.assertEqual(self.ciphertext, ct2) # encrypt (second time)
self.assertEqual(self.plaintext, pt1) # decrypt
self.assertEqual(self.plaintext, pt2) # decrypt (second time)
class CipherStreamingSelfTest(CipherSelfTest):
def shortDescription(self):
desc = self.module_name
if self.mode is not None:
desc += " in %s mode" % (self.mode_name,)
return "%s should behave like a stream cipher" % (desc,)
def runTest(self):
plaintext = a2b_hex(self.plaintext)
ciphertext = a2b_hex(self.ciphertext)
# The cipher should work like a stream cipher
# Test counter mode encryption, 3 bytes at a time
ct3 = []
cipher = self._new()
for i in range(0, len(plaintext), 3):
ct3.append(cipher.encrypt(plaintext[i:i+3]))
ct3 = b2a_hex("".join(ct3))
self.assertEqual(self.ciphertext, ct3) # encryption (3 bytes at a time)
# Test counter mode decryption, 3 bytes at a time
pt3 = []
cipher = self._new()
for i in range(0, len(ciphertext), 3):
pt3.append(cipher.encrypt(ciphertext[i:i+3]))
pt3 = b2a_hex("".join(pt3))
self.assertEqual(self.plaintext, pt3) # decryption (3 bytes at a time)
class CTRSegfaultTest(unittest.TestCase):
def __init__(self, module, params):
unittest.TestCase.__init__(self)
self.module = module
self.key = params['key']
self.module_name = params.get('module_name', None)
def shortDescription(self):
return """Regression test: %s.new(key, %s.MODE_CTR) should raise TypeError, not segfault""" % (self.module_name, self.module_name)
def runTest(self):
self.assertRaises(TypeError, self.module.new, a2b_hex(self.key), self.module.MODE_CTR)
class CTRWraparoundTest(unittest.TestCase):
def __init__(self, module, params):
unittest.TestCase.__init__(self)
self.module = module
self.key = params['key']
self.module_name = params.get('module_name', None)
def shortDescription(self):
return """Regression test: %s with MODE_CTR should raise OverflowError on wraparound when shortcut used""" % (self.module_name,)
def runTest(self):
from Crypto.Util import Counter
for disable_shortcut in (0, 1): # (False, True) Test CTR-mode shortcut and PyObject_CallObject code paths
for little_endian in (0, 1): # (False, True) Test both endiannesses
ctr = Counter.new(8*self.module.block_size, initial_value=2L**(8*self.module.block_size)-1, little_endian=little_endian, disable_shortcut=disable_shortcut)
cipher = self.module.new(a2b_hex(self.key), self.module.MODE_CTR, counter=ctr)
block = "\x00" * self.module.block_size
cipher.encrypt(block)
self.assertRaises(OverflowError, cipher.encrypt, block)
class CFBSegmentSizeTest(unittest.TestCase):
def __init__(self, module, params):
unittest.TestCase.__init__(self)
self.module = module
self.key = params['key']
self.description = params['description']
def shortDescription(self):
return self.description
def runTest(self):
"""Regression test: m.new(key, m.MODE_CFB, segment_size=N) should require segment_size to be a multiple of 8 bits"""
for i in range(1, 8):
self.assertRaises(ValueError, self.module.new, a2b_hex(self.key), self.module.MODE_CFB, segment_size=i)
self.module.new(a2b_hex(self.key), self.module.MODE_CFB, segment_size=8) # should succeed
def make_block_tests(module, module_name, test_data):
tests = []
extra_tests_added = 0
for i in range(len(test_data)):
row = test_data[i]
# Build the "params" dictionary
params = {'mode': 'ECB'}
if len(row) == 3:
(params['plaintext'], params['ciphertext'], params['key']) = row
elif len(row) == 4:
(params['plaintext'], params['ciphertext'], params['key'], params['description']) = row
elif len(row) == 5:
(params['plaintext'], params['ciphertext'], params['key'], params['description'], extra_params) = row
params.update(extra_params)
else:
raise AssertionError("Unsupported tuple size %d" % (len(row),))
# Build the display-name for the test
p2 = params.copy()
p_key = _extract(p2, 'key')
p_plaintext = _extract(p2, 'plaintext')
p_ciphertext = _extract(p2, 'ciphertext')
p_description = _extract(p2, 'description', None)
p_mode = p2.get('mode', 'ECB')
if p_mode == 'ECB':
_extract(p2, 'mode', 'ECB')
if p_description is not None:
description = p_description
elif p_mode == 'ECB' and not p2:
description = "p=%s, k=%s" % (p_plaintext, p_key)
else:
description = "p=%s, k=%s, %r" % (p_plaintext, p_key, p2)
name = "%s #%d: %s" % (module_name, i+1, description)
params['description'] = name
params['module_name'] = module_name
# Add extra test(s) to the test suite before the current test
if not extra_tests_added:
tests += [
CTRSegfaultTest(module, params),
CTRWraparoundTest(module, params),
CFBSegmentSizeTest(module, params),
]
extra_tests_added = 1
# Add the current test to the test suite
tests.append(CipherSelfTest(module, params))
# When using CTR mode, test that the interface behaves like a stream cipher
if p_mode == 'CTR':
tests.append(CipherStreamingSelfTest(module, params))
# When using CTR mode, test the non-shortcut code path.
if p_mode == 'CTR' and not params.has_key('ctr_class'):
params2 = params.copy()
params2['description'] += " (shortcut disabled)"
ctr_params2 = params.get('ctr_params', {}).copy()
params2['ctr_params'] = ctr_params2
if not params2['ctr_params'].has_key('disable_shortcut'):
params2['ctr_params']['disable_shortcut'] = 1
tests.append(CipherSelfTest(module, params2))
return tests
def make_stream_tests(module, module_name, test_data):
tests = []
for i in range(len(test_data)):
row = test_data[i]
# Build the "params" dictionary
params = {}
if len(row) == 3:
(params['plaintext'], params['ciphertext'], params['key']) = row
elif len(row) == 4:
(params['plaintext'], params['ciphertext'], params['key'], params['description']) = row
elif len(row) == 5:
(params['plaintext'], params['ciphertext'], params['key'], params['description'], extra_params) = row
params.update(extra_params)
else:
raise AssertionError("Unsupported tuple size %d" % (len(row),))
# Build the display-name for the test
p2 = params.copy()
p_key = _extract(p2, 'key')
p_plaintext = _extract(p2, 'plaintext')
p_ciphertext = _extract(p2, 'ciphertext')
p_description = _extract(p2, 'description', None)
if p_description is not None:
description = p_description
elif not p2:
description = "p=%s, k=%s" % (p_plaintext, p_key)
else:
description = "p=%s, k=%s, %r" % (p_plaintext, p_key, p2)
name = "%s #%d: %s" % (module_name, i+1, description)
params['description'] = name
params['module_name'] = module_name
# Add the test to the test suite
tests.append(CipherSelfTest(module, params))
tests.append(CipherStreamingSelfTest(module, params))
return tests
# vim:set ts=4 sw=4 sts=4 expandtab:
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