Commit 3b4a8557 authored by Dr. Stephen Henson's avatar Dr. Stephen Henson
Browse files

Don't need separate tag buffer for GCM mode: use EVP_CIPHER_CTX buf 

field which is not unused for custom ciphers.
parent ca8630ba

crypto/evp/e_aes.c

+4 −6
Original line number Diff line number Diff line
@@ -201,8 +201,6 @@ typedef struct 
	unsigned char *iv;

	/* IV length */

	int ivlen;

	/* Tag to verify */

	unsigned char tag[16];

	int taglen;

	/* It is OK to generate IVs */

	int iv_gen;
@@ -268,14 +266,14 @@ static int aes_gcm_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr) 
	case EVP_CTRL_GCM_SET_TAG:

		if (arg <= 0 || arg > 16 || c->encrypt)

			return 0;

		memcpy(gctx->tag, ptr, arg);

		memcpy(c->buf, ptr, arg);

		gctx->taglen = arg;

		return 1;



	case EVP_CTRL_GCM_GET_TAG:

		if (arg <= 0 || arg > 16 || !c->encrypt || gctx->taglen < 0)

			return 0;

		memcpy(ptr, gctx->tag, arg);

		memcpy(ptr, c->buf, arg);

		return 1;



	case EVP_CTRL_GCM_SET_IV_FIXED:
@@ -385,12 +383,12 @@ static int aes_gcm(EVP_CIPHER_CTX *ctx, unsigned char *out, 
		if (!ctx->encrypt)

			{

			if (CRYPTO_gcm128_finish(&gctx->gcm,

					gctx->tag, gctx->taglen) != 0)

					ctx->buf, gctx->taglen) != 0)

				return -1;

			gctx->iv_set = 0;

			return 0;

			}

		CRYPTO_gcm128_tag(&gctx->gcm, gctx->tag, 16);

		CRYPTO_gcm128_tag(&gctx->gcm, ctx->buf, 16);

		gctx->taglen = 16;

		/* Don't reuse the IV */

		gctx->iv_set = 0;