1
vote
1answer
111 views

SSL Handshake random number?

I realized all of the phase of the handshake but I do not understand how it does that from the two randomly generated numbers are unable to generate a session key that the client and the server uses ...
6
votes
2answers
186 views

What to consider when generating random code as part of two-factor authentication?

I want to write a patch for a two factor authentication system that someone else has started. The code is a module for a PHP content management system and sends an SMS message to a user's phone, after ...
8
votes
2answers
523 views

Is a rand from glibc's rand secure for a login key?

Same question as Is a rand from /dev/urandom secure for a login key, but with glibc's rand function instead of /dev/urandom. And what would be a sufficiently secure seed generator?
68
votes
3answers
9k views

Is a rand from /dev/urandom secure for a login key?

Lets say I want to create a cookie for a user. Would simply generating a 1024 bit string by using /dev/urandom, and checking if it already exists (looping until I get a unique one) suffice? Or should ...