[PATCH v2 11/15] lib/crypto: sha3: Support arch overrides of one-shot digest functions

[Eric Biggers]

Add support for architecture-specific overrides of sha3_224(),
sha3_256(), sha3_384(), and sha3_512().  This will be used to implement
these functions more efficiently on s390 than is possible via the usual
init + update + final flow.

Signed-off-by: Eric Biggers <ebiggers at kernel.org>
---
 lib/crypto/sha3.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/lib/crypto/sha3.c b/lib/crypto/sha3.c
index 6c94b4ebd0fd1..a598138d47a59 100644
--- a/lib/crypto/sha3.c
+++ b/lib/crypto/sha3.c
@@ -278,44 +278,81 @@ void shake_squeeze(struct shake_ctx *shake_ctx, u8 *out, size_t out_len)
 	}
 	ctx->squeeze_offset = squeeze_offset;
 }
 EXPORT_SYMBOL_GPL(shake_squeeze);
 
+#ifndef sha3_224_arch
+static inline bool sha3_224_arch(const u8 *in, size_t in_len,
+				 u8 out[SHA3_224_DIGEST_SIZE])
+{
+	return false;
+}
+#endif
+#ifndef sha3_256_arch
+static inline bool sha3_256_arch(const u8 *in, size_t in_len,
+				 u8 out[SHA3_256_DIGEST_SIZE])
+{
+	return false;
+}
+#endif
+#ifndef sha3_384_arch
+static inline bool sha3_384_arch(const u8 *in, size_t in_len,
+				 u8 out[SHA3_384_DIGEST_SIZE])
+{
+	return false;
+}
+#endif
+#ifndef sha3_512_arch
+static inline bool sha3_512_arch(const u8 *in, size_t in_len,
+				 u8 out[SHA3_512_DIGEST_SIZE])
+{
+	return false;
+}
+#endif
+
 void sha3_224(const u8 *in, size_t in_len, u8 out[SHA3_224_DIGEST_SIZE])
 {
 	struct sha3_ctx ctx;
 
+	if (sha3_224_arch(in, in_len, out))
+		return;
 	sha3_224_init(&ctx);
 	sha3_update(&ctx, in, in_len);
 	sha3_final(&ctx, out);
 }
 EXPORT_SYMBOL_GPL(sha3_224);
 
 void sha3_256(const u8 *in, size_t in_len, u8 out[SHA3_256_DIGEST_SIZE])
 {
 	struct sha3_ctx ctx;
 
+	if (sha3_256_arch(in, in_len, out))
+		return;
 	sha3_256_init(&ctx);
 	sha3_update(&ctx, in, in_len);
 	sha3_final(&ctx, out);
 }
 EXPORT_SYMBOL_GPL(sha3_256);
 
 void sha3_384(const u8 *in, size_t in_len, u8 out[SHA3_384_DIGEST_SIZE])
 {
 	struct sha3_ctx ctx;
 
+	if (sha3_384_arch(in, in_len, out))
+		return;
 	sha3_384_init(&ctx);
 	sha3_update(&ctx, in, in_len);
 	sha3_final(&ctx, out);
 }
 EXPORT_SYMBOL_GPL(sha3_384);
 
 void sha3_512(const u8 *in, size_t in_len, u8 out[SHA3_512_DIGEST_SIZE])
 {
 	struct sha3_ctx ctx;
 
+	if (sha3_512_arch(in, in_len, out))
+		return;
 	sha3_512_init(&ctx);
 	sha3_update(&ctx, in, in_len);
 	sha3_final(&ctx, out);
 }
 EXPORT_SYMBOL_GPL(sha3_512);
-- 
2.51.1.dirty