lib/crypto: sha256: Document the SHA-224 and SHA-256 API

Add kerneldoc comments, consistent with the kerneldoc comments of the
SHA-384 and SHA-512 API.

Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250630160645.3198-15-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

1 files changed, 76 insertions, 0 deletions

diff --git a/include/crypto/sha2.h b/include/crypto/sha2.h
index 2e3fc2cf4aa0..e0a08f6addd0 100644
--- a/include/crypto/sha2.h
+++ b/include/crypto/sha2.h
@@ -155,13 +155,51 @@ struct sha224_ctx {
 	struct __sha256_ctx ctx;
 };
 
+/**
+ * sha224_init() - Initialize a SHA-224 context for a new message
+ * @ctx: the context to initialize
+ *
+ * If you don't need incremental computation, consider sha224() instead.
+ *
+ * Context: Any context.
+ */
 void sha224_init(struct sha224_ctx *ctx);
+
+/**
+ * sha224_update() - Update a SHA-224 context with message data
+ * @ctx: the context to update; must have been initialized
+ * @data: the message data
+ * @len: the data length in bytes
+ *
+ * This can be called any number of times.
+ *
+ * Context: Any context.
+ */
 static inline void sha224_update(struct sha224_ctx *ctx,
 				 const u8 *data, size_t len)
 {
 	__sha256_update(&ctx->ctx, data, len);
 }
+
+/**
+ * sha224_final() - Finish computing a SHA-224 message digest
+ * @ctx: the context to finalize; must have been initialized
+ * @out: (output) the resulting SHA-224 message digest
+ *
+ * After finishing, this zeroizes @ctx.  So the caller does not need to do it.
+ *
+ * Context: Any context.
+ */
 void sha224_final(struct sha224_ctx *ctx, u8 out[SHA224_DIGEST_SIZE]);
+
+/**
+ * sha224() - Compute SHA-224 message digest in one shot
+ * @data: the message data
+ * @len: the data length in bytes
+ * @out: (output) the resulting SHA-224 message digest
+ *
+ * Context: Any context.
+ */
 void sha224(const u8 *data, size_t len, u8 out[SHA224_DIGEST_SIZE]);
 
 /**
@@ -275,13 +313,51 @@ struct sha256_ctx {
 	struct __sha256_ctx ctx;
 };
 
+/**
+ * sha256_init() - Initialize a SHA-256 context for a new message
+ * @ctx: the context to initialize
+ *
+ * If you don't need incremental computation, consider sha256() instead.
+ *
+ * Context: Any context.
+ */
 void sha256_init(struct sha256_ctx *ctx);
+
+/**
+ * sha256_update() - Update a SHA-256 context with message data
+ * @ctx: the context to update; must have been initialized
+ * @data: the message data
+ * @len: the data length in bytes
+ *
+ * This can be called any number of times.
+ *
+ * Context: Any context.
+ */
 static inline void sha256_update(struct sha256_ctx *ctx,
 				 const u8 *data, size_t len)
 {
 	__sha256_update(&ctx->ctx, data, len);
 }
+
+/**
+ * sha256_final() - Finish computing a SHA-256 message digest
+ * @ctx: the context to finalize; must have been initialized
+ * @out: (output) the resulting SHA-256 message digest
+ *
+ * After finishing, this zeroizes @ctx.  So the caller does not need to do it.
+ *
+ * Context: Any context.
+ */
 void sha256_final(struct sha256_ctx *ctx, u8 out[SHA256_DIGEST_SIZE]);
+
+/**
+ * sha256() - Compute SHA-256 message digest in one shot
+ * @data: the message data
+ * @len: the data length in bytes
+ * @out: (output) the resulting SHA-256 message digest
+ *
+ * Context: Any context.
+ */
 void sha256(const u8 *data, size_t len, u8 out[SHA256_DIGEST_SIZE]);
 
 /**