crypto: sha3-generic - export init/update/final routines

To allow accelerated implementations to fall back to the generic
routines, e.g., in contexts where a SIMD based implementation is
not allowed to run, expose the generic SHA3 init/update/final
routines to other modules.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/sha3_generic.c

@@ -145,7 +145,7 @@ static void __attribute__((__optimize__("O3"))) keccakf(u64 st[25])
 	}
 }
 
-static int sha3_init(struct shash_desc *desc)
+int crypto_sha3_init(struct shash_desc *desc)
 {
 	struct sha3_state *sctx = shash_desc_ctx(desc);
 	unsigned int digest_size = crypto_shash_digestsize(desc->tfm);
@@ -157,8 +157,9 @@ static int sha3_init(struct shash_desc *desc)
 	memset(sctx->st, 0, sizeof(sctx->st));
 	return 0;
 }
+EXPORT_SYMBOL(crypto_sha3_init);
 
-static int sha3_update(struct shash_desc *desc, const u8 *data,
+int crypto_sha3_update(struct shash_desc *desc, const u8 *data,
 		       unsigned int len)
 {
 	struct sha3_state *sctx = shash_desc_ctx(desc);
@@ -194,8 +195,9 @@ static int sha3_update(struct shash_desc *desc, const u8 *data,
 
 	return 0;
 }
+EXPORT_SYMBOL(crypto_sha3_update);
 
-static int sha3_final(struct shash_desc *desc, u8 *out)
+int crypto_sha3_final(struct shash_desc *desc, u8 *out)
 {
 	struct sha3_state *sctx = shash_desc_ctx(desc);
 	unsigned int i, inlen = sctx->partial;
@@ -220,12 +222,13 @@ static int sha3_final(struct shash_desc *desc, u8 *out)
 	memset(sctx, 0, sizeof(*sctx));
 	return 0;
 }
+EXPORT_SYMBOL(crypto_sha3_final);
 
 static struct shash_alg algs[] = { {
 	.digestsize		= SHA3_224_DIGEST_SIZE,
-	.init			= sha3_init,
-	.update			= sha3_update,
-	.final			= sha3_final,
+	.init			= crypto_sha3_init,
+	.update			= crypto_sha3_update,
+	.final			= crypto_sha3_final,
 	.descsize		= sizeof(struct sha3_state),
 	.base.cra_name		= "sha3-224",
 	.base.cra_driver_name	= "sha3-224-generic",
@@ -234,9 +237,9 @@ static struct shash_alg algs[] = { {
 	.base.cra_module	= THIS_MODULE,
 }, {
 	.digestsize		= SHA3_256_DIGEST_SIZE,
-	.init			= sha3_init,
-	.update			= sha3_update,
-	.final			= sha3_final,
+	.init			= crypto_sha3_init,
+	.update			= crypto_sha3_update,
+	.final			= crypto_sha3_final,
 	.descsize		= sizeof(struct sha3_state),
 	.base.cra_name		= "sha3-256",
 	.base.cra_driver_name	= "sha3-256-generic",
@@ -245,9 +248,9 @@ static struct shash_alg algs[] = { {
 	.base.cra_module	= THIS_MODULE,
 }, {
 	.digestsize		= SHA3_384_DIGEST_SIZE,
-	.init			= sha3_init,
-	.update			= sha3_update,
-	.final			= sha3_final,
+	.init			= crypto_sha3_init,
+	.update			= crypto_sha3_update,
+	.final			= crypto_sha3_final,
 	.descsize		= sizeof(struct sha3_state),
 	.base.cra_name		= "sha3-384",
 	.base.cra_driver_name	= "sha3-384-generic",
@@ -256,9 +259,9 @@ static struct shash_alg algs[] = { {
 	.base.cra_module	= THIS_MODULE,
 }, {
 	.digestsize		= SHA3_512_DIGEST_SIZE,
-	.init			= sha3_init,
-	.update			= sha3_update,
-	.final			= sha3_final,
+	.init			= crypto_sha3_init,
+	.update			= crypto_sha3_update,
+	.final			= crypto_sha3_final,
 	.descsize		= sizeof(struct sha3_state),
 	.base.cra_name		= "sha3-512",
 	.base.cra_driver_name	= "sha3-512-generic",

include/crypto/sha3.h

@@ -26,4 +26,9 @@ struct sha3_state {
 	u8		buf[SHA3_224_BLOCK_SIZE];
 };
 
+int crypto_sha3_init(struct shash_desc *desc);
+int crypto_sha3_update(struct shash_desc *desc, const u8 *data,
+		       unsigned int len);
+int crypto_sha3_final(struct shash_desc *desc, u8 *out);
+
 #endif