From 19762575090d0f3c83c610de2a65cccf0c135516 Mon Sep 17 00:00:00 2001 From: Sverker Eriksson Date: Thu, 23 Sep 2010 16:39:30 +0200 Subject: crypto CTR support --- lib/crypto/c_src/crypto.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'lib/crypto/c_src/crypto.c') diff --git a/lib/crypto/c_src/crypto.c b/lib/crypto/c_src/crypto.c index 85614a84c2..92cc2b4dd9 100644 --- a/lib/crypto/c_src/crypto.c +++ b/lib/crypto/c_src/crypto.c @@ -126,6 +126,7 @@ static ERL_NIF_TERM des_cbc_crypt(ErlNifEnv* env, int argc, const ERL_NIF_TERM a static ERL_NIF_TERM des_ecb_crypt(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]); static ERL_NIF_TERM des_ede3_cbc_crypt(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]); static ERL_NIF_TERM aes_cfb_128_crypt(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]); +static ERL_NIF_TERM aes_ctr_encrypt(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]); static ERL_NIF_TERM rand_bytes_1(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]); static ERL_NIF_TERM rand_bytes_3(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]); static ERL_NIF_TERM rand_uniform_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]); @@ -194,6 +195,8 @@ static ErlNifFunc nif_funcs[] = { {"des_ecb_crypt", 3, des_ecb_crypt}, {"des_ede3_cbc_crypt", 6, des_ede3_cbc_crypt}, {"aes_cfb_128_crypt", 4, aes_cfb_128_crypt}, + {"aes_ctr_encrypt", 3, aes_ctr_encrypt}, + {"aes_ctr_decrypt", 3, aes_ctr_encrypt}, {"rand_bytes", 1, rand_bytes_1}, {"rand_bytes", 3, rand_bytes_3}, {"rand_uniform_nif", 2, rand_uniform_nif}, @@ -654,6 +657,34 @@ static ERL_NIF_TERM aes_cfb_128_crypt(ErlNifEnv* env, int argc, const ERL_NIF_TE return ret; } +/* Common for both encrypt and decrypt +*/ +static ERL_NIF_TERM aes_ctr_encrypt(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) +{/* (Key, IVec, Data) */ + ErlNifBinary key, ivec, text; + AES_KEY aes_key; + unsigned char ivec_clone[16]; /* writable copy */ + unsigned char ecount_buf[AES_BLOCK_SIZE]; + unsigned int num = 0; + ERL_NIF_TERM ret; + + if (!enif_inspect_iolist_as_binary(env, argv[0], &key) + || AES_set_encrypt_key(key.data, key.size*8, &aes_key) != 0 + || !enif_inspect_binary(env, argv[1], &ivec) || ivec.size != 16 + || !enif_inspect_iolist_as_binary(env, argv[2], &text)) { + return enif_make_badarg(env); + } + memcpy(ivec_clone, ivec.data, 16); + memset(ecount_buf, 0, sizeof(ecount_buf)); + AES_ctr128_encrypt((unsigned char *) text.data, + enif_make_new_binary(env, text.size, &ret), + text.size, &aes_key, ivec_clone, ecount_buf, &num); + + /* To do an incremental {en|de}cryption, the state to to keep between calls + must include ivec_clone, ecount_buf and num. */ + return ret; +} + static ERL_NIF_TERM rand_bytes_1(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]) {/* (Bytes) */ unsigned bytes; -- cgit v1.2.3