How to use openssl to base 64 decode?

Question

I am developing in C++ using Boost.Asio. I want to be able to base64 decode data and since Boost.Asio links to openssl I want to use it's functions to do so and not add an extra dependency(eg crypto++). I have found this code here that shows how to do it. (change int finalLen = BIO_read(bmem, (void*)pOut, outLen); to inLen )

I don't know if it works. I just pass to it some test data that I verify with an online decoder found here(2) (select decode safely as text and count the symbols). The test string I use is this one: "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=" (without the ""). Both the online decoder and a quick crypto++ implementation return 23 chars. But the code I mentioned above using openssl returns 0. Am I doing something wrong? Is openssl suitable for base64 decoding? Please provide me a solution(if one exists). Thanks for you time.

(2)http://www.opinionatedgeek.com/dotnet/tools/base64decode/

Answer 1

pff sorry my mistake. I forgot to allocate memory for pOut. The code seems to work now.