On Sun, Nov 4, 2012 at 11:04 PM, Niels Möller nisse@lysator.liu.se wrote:
Attached is an updated version of the patch.
+void +gosthash94_digest (gosthash94_ctx * ctx, unsigned length, uint8_t *result) +{
- unsigned index = ctx->length & 31;
- uint32_t *msg32 = (uint32_t*)ctx->message;
- assert(length <= GOSTHASH94_DIGEST_SIZE);
- /* pad the last block with zeroes and hash it */
- if (index > 0)
{memset (ctx->message + index, 0, 32 - index);gost_compute_sum_and_hash (ctx, ctx->message);}- /* hash the message length and the sum */
- msg32[0] = (uint32_t) (ctx->length << 3);
- msg32[1] = (uint32_t) (ctx->length >> 29);
- memset (msg32 + 2, 0, sizeof (uint32_t) * 6);
- gost_block_compress (ctx, msg32);
- gost_block_compress (ctx, ctx->sum);
- /* convert hash state to result bytes */
- _nettle_write_le32(length, result, ctx->hash);
+}
Any good reason for reusing the ctx->message as msg32? The cast looks dangerous, even if maybe it isn't (potentially it could have bad alignment, but not with the current struct layout). I'd replace that with a local array,
uint32_t msg32[8];
Hello, I remember I noticed that also, but postponed it for after I finished the porting. It seems I forgot it then, or had some issue with the change and abandoned it. I'll add it in my todo list, but if it is an easy fix you may want to just update it.
Also, the _digest function should reset the state when it's done, in the same way as _init. Which is easy, just call _init, or memset directly.
Added to.
regards, Nikos