iOS - How to generate random IV in ECB mode?

Question

I want to generate random IV in iOS which is base on the below code:

mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND);

Is anybody can tell me how to generate random IV in iOS same with the above php? Thank you.

Answer 1

This question is unanswerable (it's akin to "what is the sound of one hand clapping?"), but in the interest of guiding people who come upon it in the future:

• As Artjom B. pointed out in the comments, ECB mode doesn't accept an IV
• Don't write crypto code (the entire CryptoFails blog is worth reading)
• ECB mode sucks for security

What to do instead: See this answer .