how to generate 16 bytes random number in python and xor them

Question

Im writing my own version of ssl and in order to create a master key, I need to create 2 random numbers of 16 bytes and xor them. can someone help me doing so?

[How random do they need to be](http://www.bishopfox.com/blog/2012/03/ssl-key-generation-weaknesses/)? — Peter Wood, Jul 11 '15 at 07:28
Possible duplicate of [How to generate random number with the specific length in python](http://stackoverflow.com/q/2673385) or [Bitwise XOR of hex numbers in python](http://stackoverflow.com/questions/11119632/bitwise-xor-of-hex-numbers-in-python). If you don't know how to perform an XOR, do you really think its a good idea to write a TLS library? — jww, Jul 11 '15 at 19:27

hiro protagonist · Answer 1 · 2015-07-11T08:05:16.667

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i hope you do this for scientific purposes... ssl is huge. and - as always in crypto - a lot can go wrong with an implementation... good luck!

import os
print(os.urandom(16))

but as an effort to study/improve e.g. openssl, that would be a very welcome effort!

edited Jul 11 '15 at 08:05

answered Jul 11 '15 at 07:49

hiro protagonist

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its just a little project I got... little vbersion of ssl, nothing huge. thanks alot! – ransar Jul 11 '15 at 08:13

score 2 · Answer 2 · answered Jul 11 '15 at 07:48

2

What about

int(os.urandom(16).encode('hex'),16) ^ int(os.urandom(16).encode('hex'),16)

answered Jul 11 '15 at 07:48

jimijimjim

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score 1 · Answer 3 · answered Jul 11 '15 at 07:53

It is often operating system and computer (i.e. hardware) specific.

On Linux, you could use /dev/random (read 16 bytes from it) but read random(4) first.

Be very careful, it is a very sensitive issue and a lot of things can go silently wrong.

BTW, I don't think that rewriting SSL from scratch is reasonable (except for learning purposes).

how to generate 16 bytes random number in python and xor them

3 Answers3