for p in range(16):
cph_guess[b*16+p] = chr(ord(cph[b*16+p]) ^ ord(block_guess[p]))
print_msg( "cph_guess after xor with block: %s" % repr(cph_guess[b*16:b*16+16]))
for p in range(pos-1,16):
print_msg( "Padding byte: %s with value: %s" % (b*16+p+1, 17-pos))
cph_guess[b*16+p] = chr(ord(cph_guess[b*16+p]) ^ (17 - pos))
print_msg( "cph_guess after xor with pad byte: %s" % repr(cph_guess[b*16:b*16+16]))
if decrypt_and_check_pad(a, "".join(cph_guess)):
print_msg( "Valid!!!")
return block
else:
print_msg( "Not valid padding")
return block
decrypted_msg = ""
for i in range(len(cph)/16):
block = ["\x00"]
decrypted_block = decrypt_block(aes, cph, block, 1, 0)
print "\nDecrypted a block!\n"
print repr(decrypted_block)
decrypted_msg = "".join(decrypted_block) + decrypted_msg
cph = cph[:-16]
print aes.pkcs7chk(decrypted_msg)
