[PATCH 09/18] lib/crypto: sha256: Add sha224() and sha224_update()

Eric Biggers
2025-06-25T07:10:31Z

Add a one-shot SHA-224 computation function sha224(), for consistency
with sha256(), sha384(), and sha512() which all already exist.

Similarly, add sha224_update(). While for now it's identical to
sha256_update(), omitting it makes the API harder to use since users
have to "know" which functions are the same between SHA-224 and SHA-256.
Also, this is a prerequisite for using different context types for each.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
---
include/crypto/sha2.h | 10 ++++++++--
lib/crypto/sha256.c | 10 ++++++++++
lib/crypto/tests/sha224_kunit.c | 13 +------------
3 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/include/crypto/sha2.h b/include/crypto/sha2.h
index bb181b7996cdc..e31da0743a522 100644
--- a/include/crypto/sha2.h
+++ b/include/crypto/sha2.h
@@ -112,22 +112,28 @@ struct sha512_state {
u64 state[SHA512_DIGEST_SIZE / 8];
u64 count[2];
u8 buf[SHA512_BLOCK_SIZE];
};

+void sha256_update(struct sha256_state *sctx, const u8 *data, size_t len);
+
static inline void sha224_init(struct sha256_state *sctx)
{
sha224_block_init(&sctx->ctx);
}
-/* Simply use sha256_update as it is equivalent to sha224_update. */
+static inline void sha224_update(struct sha256_state *sctx,
+ const u8 *data, size_t len)
+{
+ sha256_update(sctx, data, len);
+}
void sha224_final(struct sha256_state *sctx, u8 out[SHA224_DIGEST_SIZE]);
+void sha224(const u8 *data, size_t len, u8 out[SHA224_DIGEST_SIZE]);

static inline void sha256_init(struct sha256_state *sctx)
{
sha256_block_init(&sctx->ctx);
}
-void sha256_update(struct sha256_state *sctx, const u8 *data, size_t len);
void sha256_final(struct sha256_state *sctx, u8 out[SHA256_DIGEST_SIZE]);
void sha256(const u8 *data, size_t len, u8 out[SHA256_DIGEST_SIZE]);

/* State for the SHA-512 (and SHA-384) compression function */
struct sha512_block_state {
diff --git a/lib/crypto/sha256.c b/lib/crypto/sha256.c
index 573ccecbf48bf..ccaae70880166 100644
--- a/lib/crypto/sha256.c
+++ b/lib/crypto/sha256.c
@@ -68,10 +68,20 @@ void sha256_final(struct sha256_state *sctx, u8 out[SHA256_DIGEST_SIZE])
{
__sha256_final(sctx, out, SHA256_DIGEST_SIZE);
}
EXPORT_SYMBOL(sha256_final);

+void sha224(const u8 *data, size_t len, u8 out[SHA224_DIGEST_SIZE])
+{
+ struct sha256_state sctx;
+
+ sha224_init(&sctx);
+ sha224_update(&sctx, data, len);
+ sha224_final(&sctx, out);
+}
+EXPORT_SYMBOL(sha224);
+
void sha256(const u8 *data, size_t len, u8 out[SHA256_DIGEST_SIZE])
{
struct sha256_state sctx;

sha256_init(&sctx);
diff --git a/lib/crypto/tests/sha224_kunit.c b/lib/crypto/tests/sha224_kunit.c
index 5015861a55112..c484c1d4a2a5e 100644
--- a/lib/crypto/tests/sha224_kunit.c
+++ b/lib/crypto/tests/sha224_kunit.c
@@ -3,26 +3,15 @@
* Copyright 2025 Google LLC
*/
#include <crypto/sha2.h>
#include "sha224-testvecs.h"

-/* TODO: add sha224() to the library itself */
-static inline void sha224(const u8 *data, size_t len,
- u8 out[SHA224_DIGEST_SIZE])
-{
- struct sha256_state state;
-
- sha224_init(&state);
- sha256_update(&state, data, len);
- sha224_final(&state, out);
-}
-
#define HASH sha224
#define HASH_CTX sha256_state
#define HASH_SIZE SHA224_DIGEST_SIZE
#define HASH_INIT sha224_init
-#define HASH_UPDATE sha256_update
+#define HASH_UPDATE sha224_update
#define HASH_FINAL sha224_final
#define HASH_TESTVECS sha224_testvecs
/* TODO: add HMAC-SHA224 support to the library, then enable the tests for it */
#include "hash-test-template.h"

--
2.50.0