def cbc_encrypt(text, key, iv):
''' CBC encrypt text with initialization vector iv and key '''
block_length = len(iv)
text = pkcs_padding(text, block_length)
blocks = util.blocks(text, block_length)
blocks[0] = util.string_xor(blocks[0], iv)
blocks[0] = util.ecb_encrypt(blocks[0], key)
for i in xrange(1, len(blocks)):
blocks[i] = util.string_xor(blocks[i], blocks[i - 1])
blocks[i] = util.ecb_encrypt(blocks[i], key)
return ''.join(blocks)
def cbc_encrypt(text, key, iv):
''' CBC encrypt text with initialization vector iv and key '''
block_length = len(iv)
text = pkcs_padding(text, block_length)
blocks = util.blocks(text, block_length)
blocks[0] = util.string_xor(blocks[0], iv)
blocks[0] = util.ecb_encrypt(blocks[0], key)
for i in xrange(1, len(blocks)):
blocks[i] = util.string_xor(blocks[i], blocks[i-1])
blocks[i] = util.ecb_encrypt(blocks[i], key)
return ''.join(blocks)
def random_aes(text):
''' Encrypt text with AES 128 ECB with a chosen random key
Random key is chosen once per code invocation
'''
padding = b64decode(unknown_string) #base64
if 'key' not in random_aes.func_dict:
random_aes.key = random_string(16)
key = random_aes.key
return ecb_encrypt(text + padding, key) # 加上padding加密
def encryption_oracle(data):
prepad = Random.get_random_bytes(random.choice(range(5, 11)))
postpad = Random.get_random_bytes(random.choice(range(5, 11)))
padded = pkcs7_pad(prepad + data + postpad)
key = keygen()
if random.choice(range(2)) == 0:
iv = keygen()
return cbc_encrypt(data, key, iv)
else:
return ecb_encrypt(data, key)
def random_aes(text):
''' Encrypt text with AES 128 ECB with a chosen random key
Random key is chosen once per code invocation
'''
padding = b64decode(unknown_string)
if 'key' not in random_aes.func_dict:
random_aes.key = random_string(16)
random_aes.prefix = random_string(random.randint(0, 100))
key = random_aes.key
prefix = random_aes.prefix
return ecb_encrypt(prefix + text + padding, key)
def ctr_decrypt(text, key='YELLOW SUBMARINE', nonce=0):
''' CTR decrypt a text using key and nonce '''
block_size = len(key)
blocks = util.get_blocks(text, block_size)
c = Counter()
decrypted = ''
for block in blocks:
keystring = util.ecb_encrypt(c.next(), key)
decrypted += util.string_xor(keystring, block)
return decrypted
def encryption_oracle(text):
# Append some random bytes both ways
text = random_string(random.randint(5, 10)) + text + random_string(random.randint(5, 10))
iv = random_string(16)
key = random_string(16)
if random.randint(0, 1):
# ECB
return util.ecb_encrypt(text, key)
else:
# CBC
return cbc_encrypt(text, key, iv)
def encryption_oracle(text):
# Append some random bytes both ways
text = random_string(random.randint(5, 10)) + text + random_string(
random.randint(5, 10))
iv = random_string(16) #16bits
key = random_string(16)
if random.randint(0, 1):
# ECB
return util.ecb_encrypt(text, key)
else:
# CBC
return cbc_encrypt(text, key, iv)
def encryption_oracle(text):
# 明文两侧添加随机密文
text = random_string(random.randint(5, 10)) + text + random_string(
random.randint(5, 10))
iv = random_string(16)
key = random_string(16)
if random.randint(0, 1):
# ECB
return util.ecb_encrypt(text, key)
else:
# CBC
return cbc_encrypt(text, key, iv)
def encrypt(self, email):
''' Encrypt user profile with AES 128 ECB with a chosen random key
Random key is chosen once per code invocation
'''
key = self.key
return ecb_encrypt(self.profile_for(email), self.key)
def encrypt(self, email):
''' Encrypt user profile with AES 128 ECB with a chosen random key
Random key is chosen once per code invocation
'''
key = self.key
return ecb_encrypt(self.profile_for(email), self.key)