[slang-users] crypto module

[Arik Mitschang <arik.mitschang@xxxxxxxxx>]

Hi John,

I needed and HMAC routine a bit ago and after searching around I
noticed there was no module for cryptographic functions so I made one
myself which wraps some of the OpenSSL EVP library functions. It
provides the following:

digest
hmac
_encrypt & encrypt
_decrypt & decrypt
_genkeyiv
base64_encode
base64_decode

And the included help file has info on all but the base64 functions
(yet). I thought this might be of interest to others out there. One
thing I ran across that I wasn't sure about was leaving items on the
stack in the event of an error. For instance, the _encrypt function
first pulls a single value off the stack corresponding to the
symmetric cipher algorithm, if that doesn't exist it errors there
leaving the rest on the stack. I did this so wouldn't have to load and
free the other variables if they are certainly not going to be used.

Anyway, if you're interested the source is at:

http://web.science.mq.edu.au/~arikm/code/slcrypto/slcrypto.tar.gz

It needs the openssl library to build against, and I didn't make a
config file but something like

gcc -shared -fPIC -lslang -lcrypto crypto-module.c -o crypto-module.so

should work on a linux. The crypto.sl provides higher level encrypt
and decrypt functions with sensible defaults (and compatible with
OpenSSL command line "enc").

Thanks,
-Arik