pycrypto_AES_CTR_variations.py

import os

from Crypto.Cipher import AES
from Crypto.Util import Counter
import random
import time

datafile = "t1.dat"

BLOCK_SIZE = 16

def read_block(fname):
	block_list = []
	with open(fname, 'rb') as blobfo:
		atEOF = False
		while not atEOF:
			blobdata = blobfo.read(BLOCK_SIZE)
			block_list.append(blobdata)
			# print len(blobdata)
			if len(blobdata) < BLOCK_SIZE:
				atEOF = True
	return block_list


print 'loading data'
block_list = read_block(datafile)

print 'loading finish'
print len(block_list), 'blocks'

print 'start encryption'
NUM_COUNTER_BITS = 128
# Here I just use a random key
key = os.urandom(16)
t1 = time.time()
ct1 = []
for block in block_list:
	ctr = Counter.new(NUM_COUNTER_BITS)
	cipher = AES.new(key, AES.MODE_CTR, counter=ctr)
	ct1.append(cipher.encrypt(block))
t2 = time.time()
print 'finish encryption'

print 'total time:', "%.20f" % (t2 - t1)
print 'time for each aes:', (t2 - t1) / len(block_list)

print 'num of aes per sec:', len(block_list) / (t2 - t1)

print 'now with method 1.5'
t1 = time.time()
ctr = Counter.new(NUM_COUNTER_BITS)
cipher = AES.new(key, AES.MODE_CTR, counter=ctr)
ct2 = []
for block in block_list:
	ct2.append(cipher.encrypt(block))
t2 = time.time()
print 'finish encryption'

print 'total time:', "%.20f" % (t2 - t1)
print 'time for each aes:', (t2 - t1) / len(block_list)

print 'num of aes per sec:', len(block_list) / (t2 - t1)
	
#for b1, b2 in zip(ct1, ct2):
#	if b1 != b2:
#		print "Fail", b1, b2

print 'now try to encrypt whole file'
with open(datafile, 'rb') as f:
	block = f.read()
print type(block), len(block)
print 'start encryption'
NUM_COUNTER_BITS = 128
key = os.urandom(16)
t1 = time.time()
ctr = Counter.new(NUM_COUNTER_BITS)
cipher = AES.new(key, AES.MODE_CTR, counter=ctr)
cipher.encrypt(block)
t2 = time.time()
print 'finish encryption'

print 'total time:', t2 - t1
print 'time for each aes:', (t2 - t1) / len(block_list)

print 'num of aes per sec:', len(block_list) / (t2 - t1)