crypto: inside-secure - improve the counter computation

A counter is given to the engine when finishing hash computation. It
currently uses the blocksize while it counts the number of 64 bytes
blocks given to the engine. This works well for all algorithms so far,
as SHA1, SHA224 and SHA256 all have a blocksize of 64 bytes, but others
algorithms such as SHA512 wouldn't work.
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/inside-secure/safexcel.h

@@ -327,6 +327,11 @@ struct safexcel_context_record {
 #define CONTEXT_CONTROL_COUNTER_MODE		BIT(10)
 #define CONTEXT_CONTROL_HASH_STORE		BIT(19)
 
+/* The hash counter given to the engine in the context has a granularity of
+ * 64 bits.
+ */
+#define EIP197_COUNTER_BLOCK_SIZE		64
+
 /* EIP197_CS_RAM_CTRL */
 #define EIP197_TRC_ENABLE_0			BIT(4)
 #define EIP197_TRC_ENABLE_1			BIT(5)

drivers/crypto/inside-secure/safexcel_hash.c

@@ -72,8 +72,7 @@ static void safexcel_hash_token(struct safexcel_command_desc *cdesc,
 static void safexcel_context_control(struct safexcel_ahash_ctx *ctx,
 				     struct safexcel_ahash_req *req,
 				     struct safexcel_command_desc *cdesc,
-				     unsigned int digestsize,
-				     unsigned int blocksize)
+				     unsigned int digestsize)
 {
 	int i;
 
@@ -107,7 +106,8 @@ static void safexcel_context_control(struct safexcel_ahash_ctx *ctx,
 				ctx->base.ctxr->data[i] = cpu_to_le32(req->state[i]);
 
 			if (req->finish)
-				ctx->base.ctxr->data[i] = cpu_to_le32(req->processed / blocksize);
+				ctx->base.ctxr->data[i] =
+					cpu_to_le32(req->processed / EIP197_COUNTER_BLOCK_SIZE);
 		}
 	} else if (req->digest == CONTEXT_CONTROL_DIGEST_HMAC) {
 		cdesc->control_data.control0 |= CONTEXT_CONTROL_SIZE(2 * req->state_sz / sizeof(u32));
@@ -282,8 +282,7 @@ static int safexcel_ahash_send_req(struct crypto_async_request *async, int ring,
 
 send_command:
 	/* Setup the context options */
-	safexcel_context_control(ctx, req, first_cdesc, req->state_sz,
-				 crypto_ahash_blocksize(ahash));
+	safexcel_context_control(ctx, req, first_cdesc, req->state_sz);
 
 	/* Add the token */
 	safexcel_hash_token(first_cdesc, len, req->state_sz);
@@ -335,7 +334,6 @@ static inline bool safexcel_ahash_needs_inv_get(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);
-	struct crypto_ahash *ahash = crypto_ahash_reqtfm(areq);
 	unsigned int state_w_sz = req->state_sz / sizeof(u32);
 	int i;
 
@@ -344,7 +342,7 @@ static inline bool safexcel_ahash_needs_inv_get(struct ahash_request *areq)
 			return true;
 
 	if (ctx->base.ctxr->data[state_w_sz] !=
-	    cpu_to_le32(req->processed / crypto_ahash_blocksize(ahash)))
+	    cpu_to_le32(req->processed / EIP197_COUNTER_BLOCK_SIZE))
 		return true;
 
 	return false;