[erlang-questions] NIF Problem

[Jachym Holecek]

# Travis Jensen 2011-04-28:
> [... This results in SIGBUS after returning to Erlang ...]
> 
>  1. static ERL_NIF_TERM aes_ctr_encrypt_with_state(ErlNifEnv* env, int argc, const ERL_NIF_TERM
>     argv[])
>  2. {/* ({Key, IVec, ECount, Num}, Data) */    
>  3.     ErlNifBinary key_bin, ivec_bin, text_bin, ecount_bin;
>  4.     AES_KEY aes_key;
>  5.     unsigned int num = 0;
>  6.     ERL_NIF_TERM ret, num2_term, cipher_term, ivec2_term, ecount2_term, new_state_term;
>  7.     int state_arity;
>  8.     const ERL_NIF_TERM *state_term;
>  9.     unsigned char * ivec2_buf;
> 10.     unsigned char * ecount2_buf;
> 11.  
> 12.     if (!enif_get_tuple(env, argv[0], &state_arity, &state_term)
> 13.         || state_arity != 4
> 14.         || !enif_inspect_iolist_as_binary(env, state_term[0], &key_bin)
> 15.         || AES_set_encrypt_key(key_bin.data, key_bin.size*8, &aes_key) != 0
> 16.         || !enif_inspect_binary(env, state_term[1], &ivec_bin) || ivec_bin.size != 16
> 17.         || !enif_inspect_binary(env, state_term[2], &ecount_bin) || ecount_bin.size != 
>     AES_BLOCK_SIZE
> 18.         || !enif_get_uint(env, state_term[3], &num)
> 19.         || !enif_inspect_iolist_as_binary(env, argv[1], &text_bin)) {
> 20.         return enif_make_badarg(env);
> 21.     }
> 22.  
> 23.     ivec2_buf = enif_make_new_binary(env, ivec_bin.size, &ivec2_term);
> 24.     ecount2_buf = enif_make_new_binary(env, ecount_bin.size, &ecount2_term);
> 25.    
> 26.     memcpy(ivec2_buf, ivec_bin.data, 16);
> 27.     memcpy(ecount2_buf, ecount_bin.data, ecount_bin.size);
> 28.  
> 29.     AES_ctr128_encrypt((unsigned char *) text_bin.data,
> 30.                        enif_make_new_binary(env, text_bin.size, &cipher_term),
> 31.                        text_bin.size, &aes_key, ivec2_buf, ecount2_buf, &num);
> 32.  
> 33.     num2_term = enif_make_uint(env, num);
> 34.     new_state_term = enif_make_tuple4(env, key_bin, ivec2_term, ecount2_term, num2_term);
> 35.     ret = enif_make_tuple2(env, new_state_term, cipher_term);
> 36.     return ret;
> 37. }

Just a random guess really, but your key_bin doesn't seem to be a proper term
suitable for returning to Erlang, shoudln't you run enif_make_binary() on it?
The compiler should warn you about that too, unless ERL_NIF_TERM is something
hopelessly vague like "void *"...

Regards,
	-- Jachym