def analyze_plain(self, plain, start = 0):
"""Devine une partie de la clef grace @plain"""
i = start
key = []
index = 0
while i < len(self.cipher):
success = False
matchset = getitem(self.matches, i)
for k, data in matchset.items():
char = xor(self.cipher[i], k)
if char == plain[index]:
key.append(k)
success = True
index += 1
break
if success == False:
i -= index
index = 0
key = []
elif len(key) == len(plain):
break
i += 1
offset = i % self.keylen - len(key)
for x in xrange(len(key)):
offset += 1
offset = offset if offset >= 0 else self.keylen + offset
offset = offset % self.keylen
print "[%02d]" % offset, fmt("['%c']" % key[x], WHITE),
print
if i != len(self.cipher):
self.analyze_plain(plain, i + 1)
def analyze_plain(self, plain, start=0):
"""Devine une partie de la clef grace @plain"""
i = start
key = []
index = 0
while i < len(self.cipher):
success = False
matchset = getitem(self.matches, i)
for k, data in matchset.items():
char = xor(self.cipher[i], k)
if char == plain[index]:
key.append(k)
success = True
index += 1
break
if success == False:
i -= index
index = 0
key = []
elif len(key) == len(plain):
break
i += 1
offset = i % self.keylen - len(key)
for x in xrange(len(key)):
offset += 1
offset = offset if offset >= 0 else self.keylen + offset
offset = offset % self.keylen
print "[%02d]" % offset, fmt("['%c']" % key[x], WHITE),
print
if i != len(self.cipher):
self.analyze_plain(plain, i + 1)
def _translate(cipher, charset, offset):
"""Decalle les caracteres de @offset"""
plain = ""
for c in cipher:
if c in charset:
plain += getitem(charset, charset.index(c) + offset)
else:
plain += c
return plain
def _caesar(cipher, offset):
"""Decalle les lettres de @offset"""
plain = ""
for c in cipher:
if c.isalpha():
plain += getitem(alphacharset(c), alphaindex(c) + offset)
else:
plain += c
return plain
def _translate(cipher, charset, offset):
"""Decalle les caracteres de @offset"""
plain = ""
for c in cipher:
if c in charset:
plain += getitem(charset, charset.index(c) + offset)
else:
plain += c
return plain
def _caesar(cipher, offset):
"""Decalle les lettres de @offset"""
plain = ""
for c in cipher:
if c.isalpha():
plain += getitem(alphacharset(c), alphaindex(c) + offset)
else:
plain += c
return plain
def decrypt(cipher, key, charset=uppercase):
"""Dechiffrement"""
plain = ""
for c1, c2 in zip(cipher, key):
if c1 in charset:
i1 = charset.index(c1)
i2 = charset.index(c2)
plain += getitem(charset, i1 - i2)
else:
plain += c1
return plain
def encrypt(plain, key, charset=uppercase):
"""Chiffrement"""
cipher = ""
for c1, c2 in zip(plain, key):
if c1 in charset:
i1 = charset.index(c1)
i2 = charset.index(c2)
cipher += getitem(charset, i1 + i2)
else:
cipher += c1
return cipher
def decrypt(cipher, key, charset = uppercase):
"""Dechiffrement"""
plain = ""
for c1, c2 in zip(cipher, key):
if c1 in charset:
i1 = charset.index(c1)
i2 = charset.index(c2)
plain += getitem(charset, i1 - i2)
else:
plain += c1
return plain
def encrypt(plain, key, charset = uppercase):
"""Chiffrement"""
cipher = ""
for c1, c2 in zip(plain, key):
if c1 in charset:
i1 = charset.index(c1)
i2 = charset.index(c2)
cipher += getitem(charset, i1 + i2)
else:
cipher += c1
return cipher
def xor(text, key):
"""Fonction asm xor"""
if isinstance(key, int):
key = itos(key)
return "".join(
[chr(ord(c) ^ ord(getitem(key, i))) for i, c in enumerate(text)])