crypto: inside-secure - Added support for CRC32

This patch adds support for the CRC32 "hash" algorithm
Signed-off-by: Pascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/inside-secure/safexcel.c

@@ -1169,6 +1169,7 @@ static struct safexcel_alg_template *safexcel_algs[] = {
 	&safexcel_alg_xts_aes,
 	&safexcel_alg_gcm,
 	&safexcel_alg_ccm,
+	&safexcel_alg_crc32,
 };
 
 static int safexcel_register_algorithms(struct safexcel_crypto_priv *priv)

drivers/crypto/inside-secure/safexcel.h

@@ -362,6 +362,7 @@ struct safexcel_context_record {
 #define CONTEXT_CONTROL_DIGEST_XCM		(0x2 << 21)
 #define CONTEXT_CONTROL_DIGEST_HMAC		(0x3 << 21)
 #define CONTEXT_CONTROL_CRYPTO_ALG_MD5		(0x0 << 23)
+#define CONTEXT_CONTROL_CRYPTO_ALG_CRC32	(0x0 << 23)
 #define CONTEXT_CONTROL_CRYPTO_ALG_SHA1		(0x2 << 23)
 #define CONTEXT_CONTROL_CRYPTO_ALG_SHA224	(0x4 << 23)
 #define CONTEXT_CONTROL_CRYPTO_ALG_SHA256	(0x3 << 23)
@@ -853,5 +854,6 @@ extern struct safexcel_alg_template safexcel_alg_authenc_hmac_sha512_ctr_aes;
 extern struct safexcel_alg_template safexcel_alg_xts_aes;
 extern struct safexcel_alg_template safexcel_alg_gcm;
 extern struct safexcel_alg_template safexcel_alg_ccm;
+extern struct safexcel_alg_template safexcel_alg_crc32;
 
 #endif

drivers/crypto/inside-secure/safexcel_hash.c

@@ -82,23 +82,31 @@ static void safexcel_context_control(struct safexcel_ahash_ctx *ctx,
 	struct safexcel_crypto_priv *priv = ctx->priv;
 	u64 count = 0;
 
-	cdesc->control_data.control0 |= ctx->alg;
+	cdesc->control_data.control0 = ctx->alg;
 
 	/*
 	 * Copy the input digest if needed, and setup the context
 	 * fields. Do this now as we need it to setup the first command
 	 * descriptor.
 	 */
-	if (!req->processed) {
+	if (unlikely(req->digest == CONTEXT_CONTROL_DIGEST_XCM)) {
+		ctx->base.ctxr->data[0] = req->state[0];
+
+		cdesc->control_data.control0 |= req->digest |
+			CONTEXT_CONTROL_TYPE_HASH_OUT  |
+			CONTEXT_CONTROL_SIZE(4);
+
+		return;
+	} else if (!req->processed) {
 		/* First - and possibly only - block of basic hash only */
 		if (req->finish) {
-			cdesc->control_data.control0 |=
+			cdesc->control_data.control0 |= req->digest |
 				CONTEXT_CONTROL_TYPE_HASH_OUT |
 				CONTEXT_CONTROL_RESTART_HASH  |
 				/* ensure its not 0! */
 				CONTEXT_CONTROL_SIZE(1);
 		} else {
-			cdesc->control_data.control0 |=
+			cdesc->control_data.control0 |= req->digest |
 				CONTEXT_CONTROL_TYPE_HASH_OUT  |
 				CONTEXT_CONTROL_RESTART_HASH   |
 				CONTEXT_CONTROL_NO_FINISH_HASH |
@@ -238,9 +246,14 @@ static int safexcel_handle_req_result(struct safexcel_crypto_priv *priv,
 			return 1;
 		}
 
+		if (unlikely(sreq->digest == CONTEXT_CONTROL_DIGEST_XCM)) {
+			/* Undo final XOR with 0xffffffff ...*/
+			*(u32 *)areq->result = ~sreq->state[0];
+		} else {
 			memcpy(areq->result, sreq->state,
 			       crypto_ahash_digestsize(ahash));
 		}
+	}
 
 	cache_len = safexcel_queued_len(sreq);
 	if (cache_len)
@@ -599,7 +612,7 @@ static int safexcel_ahash_enqueue(struct ahash_request *areq)
 		     /* invalidate for HMAC continuation finish */
 		     (req->finish && (req->processed != req->block_sz)) ||
 		     /* invalidate for HMAC finish with odigest changed */
-		     (req->finish &&
+		     (req->finish && req->hmac &&
 		      memcmp(ctx->base.ctxr->data + (req->state_sz>>2),
 			     ctx->opad, req->state_sz))))
 			/*
@@ -692,6 +705,12 @@ static int safexcel_ahash_final(struct ahash_request *areq)
 			memcpy(areq->result, sha512_zero_message_hash,
 			       SHA512_DIGEST_SIZE);
 
+		return 0;
+	} else if (unlikely(req->digest == CONTEXT_CONTROL_DIGEST_XCM &&
+			    ctx->alg == CONTEXT_CONTROL_CRYPTO_ALG_MD5 &&
+			    req->len == sizeof(u32) && !areq->nbytes)) {
+		/* Zero length CRC32 */
+		memcpy(areq->result, ctx->ipad, sizeof(u32));
 		return 0;
 	} else if (unlikely(req->hmac &&
 			    (req->len == req->block_sz) &&
@@ -1740,3 +1759,85 @@ struct safexcel_alg_template safexcel_alg_hmac_md5 = {
 		},
 	},
 };
+
+static int safexcel_crc32_cra_init(struct crypto_tfm *tfm)
+{
+	struct safexcel_ahash_ctx *ctx = crypto_tfm_ctx(tfm);
+	int ret = safexcel_ahash_cra_init(tfm);
+
+	/* Default 'key' is all zeroes */
+	memset(ctx->ipad, 0, sizeof(u32));
+	return ret;
+}
+
+static int safexcel_crc32_init(struct ahash_request *areq)
+{
+	struct safexcel_ahash_ctx *ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(areq));
+	struct safexcel_ahash_req *req = ahash_request_ctx(areq);
+
+	memset(req, 0, sizeof(*req));
+
+	/* Start from loaded key */
+	req->state[0]	= cpu_to_le32(~ctx->ipad[0]);
+	/* Set processed to non-zero to enable invalidation detection */
+	req->len	= sizeof(u32);
+	req->processed	= sizeof(u32);
+
+	ctx->alg = CONTEXT_CONTROL_CRYPTO_ALG_CRC32;
+	req->digest = CONTEXT_CONTROL_DIGEST_XCM;
+	req->state_sz = sizeof(u32);
+	req->block_sz = sizeof(u32);
+
+	return 0;
+}
+
+static int safexcel_crc32_setkey(struct crypto_ahash *tfm, const u8 *key,
+				 unsigned int keylen)
+{
+	struct safexcel_ahash_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm));
+
+	if (keylen != sizeof(u32)) {
+		crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+		return -EINVAL;
+	}
+
+	memcpy(ctx->ipad, key, sizeof(u32));
+	return 0;
+}
+
+static int safexcel_crc32_digest(struct ahash_request *areq)
+{
+	return safexcel_crc32_init(areq) ?: safexcel_ahash_finup(areq);
+}
+
+struct safexcel_alg_template safexcel_alg_crc32 = {
+	.type = SAFEXCEL_ALG_TYPE_AHASH,
+	.algo_mask = 0,
+	.alg.ahash = {
+		.init = safexcel_crc32_init,
+		.update = safexcel_ahash_update,
+		.final = safexcel_ahash_final,
+		.finup = safexcel_ahash_finup,
+		.digest = safexcel_crc32_digest,
+		.setkey = safexcel_crc32_setkey,
+		.export = safexcel_ahash_export,
+		.import = safexcel_ahash_import,
+		.halg = {
+			.digestsize = sizeof(u32),
+			.statesize = sizeof(struct safexcel_ahash_export_state),
+			.base = {
+				.cra_name = "crc32",
+				.cra_driver_name = "safexcel-crc32",
+				.cra_priority = SAFEXCEL_CRA_PRIORITY,
+				.cra_flags = CRYPTO_ALG_OPTIONAL_KEY |
+					     CRYPTO_ALG_ASYNC |
+					     CRYPTO_ALG_KERN_DRIVER_ONLY,
+				.cra_blocksize = 1,
+				.cra_ctxsize = sizeof(struct safexcel_ahash_ctx),
+				.cra_init = safexcel_crc32_cra_init,
+				.cra_exit = safexcel_ahash_cra_exit,
+				.cra_module = THIS_MODULE,
+			},
+		},
+	},
+};