def extend_message(message, extension, init, key_len):
''' Length based extension attack on a sha1 keyed authentication code
Arguments:
message: Original message
extension: Message to append
init: list of sha1 init variables
key_len: length of key
'''
original_len = key_len + len(message)
glue_padding = get_glue_padding(original_len)
original_len += len(glue_padding)
new_message = message + glue_padding + extension
new_hash = sha1.sha1(extension, init, original_len)
return (new_message, new_hash)
def extend_message(message, extension, init, key_len):
''' Length based extension attack on a sha1 keyed authentication code
Arguments:
message: Original message
extension: Message to append
init: list of sha1 init variables
key_len: length of key
'''
original_len = key_len + len(message)
glue_padding = get_glue_padding(original_len)
original_len += len(glue_padding)
new_message = message + glue_padding + extension
new_hash = sha1.sha1(extension, init, original_len)
return (new_message, new_hash)
def mac(self, text):
return sha1.sha1(self.key + text)
def mac(self, text):
return sha1.sha1(self.key + text)
