def DecryptOFB(self, iv, msg_bin, chunk_size):
self.iv = iv
self.chunk_size = chunk_size
self.msg_bin = msg_bin
str = StringBinaryToDecimal()
iv_dec = str.strbin2dec(iv)
msg_list = [str.strbin2dec(msg_bin[x:x+chunk_size]) for x in xrange(0,len(msg_bin),chunk_size)]
msg_block = ''
block_encryption = 0
count = 0
while (count < len(msg_list)):
if (count == 0):
block_encryption = iv_dec ^ KEY #change encryption algorithm later
msg_list[count] ^= block_encryption
else:
block_encryption ^= KEY
msg_list[count] ^= block_encryption
msg_list[count] = bin(msg_list[count])[2:].zfill(chunk_size)
msg_block += msg_list[count]
count += 1
return msg_block
def DecryptCBC(self, msg_bin, chunk_size): #reverse of CipherBlockChaining
#self.iv = iv
self.msg_list = 0
self.key = 0
decrypted_msg = ''
str = StringBinaryToDecimal()
#b = [a[x:x+2] for x in xrange(0,len(a),2)]
msg_list = [str.strbin2dec(msg_bin[x:x+chunk_size]) for x in xrange(0,len(msg_bin),chunk_size)]
#grab last element of the CBC msg_list
iv = msg_list[len(msg_list)-1]
msg_list.pop(len(msg_list)-1) #pop initialization vector out of the list
count = len(msg_list) - 1
while (count > 0):
msg_list[count] ^= KEY
msg_list[count] ^= msg_list[count-1]
count -= 1
msg_list[count] ^= KEY
msg_list[count] ^= iv
for msg_block in msg_list:
y_bin = bin(int(msg_block))[2:].zfill(chunk_size)
decrypted_msg += y_bin
return decrypted_msg
def DecryptCFB(self, encrypt_bin_msg, chunk_size):
self.encrypt_bin_msg = encrypt_bin_msg
self.chunk_size = chunk_size
str = StringBinaryToDecimal()
decrypted_msg = ''
msg_list = [str.strbin2dec(msg_bin[x:x+chunk_size]) for x in xrange(0,len(msg_bin),chunk_size)]
def EncryptECB(self, bin_msg):
self.bin_msg = bin_msg
str = StringBinaryToDecimal()
encrypt_bin = []
for x in bin_msg:
y = bin(str.strbin2dec(x) ^ KEY)[2:] #change encryption algorithm
encrypt_bin.append(y)
return encrypt_bin
def Bin2Msg(self, decrypt_bin_msg, chunk_size):
self.decrypt_bin_msg = decrypt_bin_msg
self.chunk_size = chunk_size
str = StringBinaryToDecimal()
output_msg = ''
msg_list = [str.strbin2dec(decrypt_bin_msg[x:x+ASCII_BIN_SIZE]) for x in xrange(0,len(decrypt_bin_msg),ASCII_BIN_SIZE)]
for x in msg_list:
y = chr(x)
output_msg += y
return output_msg
def EncryptCFB(self, iv, msg_list, chunk_size):
self.iv = iv
self.msg_list = msg_list
self.chunk_size = chunk_size
str = StringBinaryToDecimal()
iv_dec = str.strbin2dec(iv)
msg_bin = ''
count = 0
while (count < len(msg_list)):
msg_list[count] = str.strbin2dec(msg_list[count])
if (count == 0):
block_encryption = iv_dec ^ KEY #change encryption algorithm
msg_list[count] ^= block_encryption
else:
block_encryption = msg_list[count-1] ^ KEY #change encryption algorithm
msg_list[count] ^= block_encryption
msg_bin += bin(int(msg_list[count]))[2:].zfill(chunk_size)
count += 1
return msg_bin
def EncryptCTR(self, iv, msg_list, chunk_size):
self.iv = iv
self.chunk_size = chunk_size
self.msg_list = msg_list
str = StringBinaryToDecimal()
iv_dec = str.strbin2dec(iv)
msg_bin = ''
block_encryption = 0
count = 0
while (count < len(msg_list)):
msg_list[count] = str.strbin2dec(msg_list[count])
block_encryption = iv_dec ^ KEY #change encryption algorithm later
msg_list[count] ^= block_encryption
msg_list[count] = bin(msg_list[count])[2:].zfill(chunk_size)
msg_bin += msg_list[count]
iv_dec +=1
count += 1
return msg_bin
def EncryptCBC(self, iv, msg_list, chunk_size):
self.iv = iv
self.msg_list = msg_list
self.key = 0;
#start the XOR-ing and encryption of the messages: m1 with iv, m2 with c1, m3 with c2
str = StringBinaryToDecimal()
iv_dec = str.strbin2dec(iv)
msg_bin = ''
#key = 5
count = 0
while (count < len(msg_list)):
if (count == 0):
#XOR the very first element in the block with the initialization vector
msg_list[count] = str.strbin2dec(msg_list[count])
msg_list[count] ^= iv_dec
msg_list[count] = bin(msg_list[count])[2:].zfill(chunk_size)
msg_list[count] = str.strbin2dec(msg_list[count])
msg_list[count] ^= KEY #change this algorithm
else:
msg_list[count] = str.strbin2dec(msg_list[count])
msg_list[count] ^= msg_list[count-1]
msg_list[count] = bin(msg_list[count])[2:].zfill(chunk_size)
msg_list[count] = str.strbin2dec(msg_list[count])
msg_list[count] ^= KEY #change this algorithm
if (msg_list[count] > ((2**chunk_size)-1)):
print "assert!!!!! You should not see this message. If you do....you messed up real bad"
count += 1
msg_list.append(str.strbin2dec(iv)) #append the iv to the very end of the message (only needed for client/server communication)
#convert encrypted message back into binary
for x_bin in msg_list:
y_bin = bin(int(x_bin))[2:].zfill(chunk_size)
msg_bin += y_bin
return msg_bin
