[PATCH 3/3] crypto: sha512 - Implement export_core() and import_core()

[Eric Biggers <ebiggers@kernel.org>]

Since commit 9d7a0ab1c753 ("crypto: ahash - Handle partial blocks in
API"), the recently-added export_core() and import_core() methods in
struct shash_alg have effectively become mandatory (even though it is
not tested or enforced), since legacy drivers that need a fallback
depend on them.  Make crypto/sha512.c compatible with these legacy
drivers by adding export_core() and import_core() methods to it.

Reported-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reported-by: Ovidiu Panait <ovidiu.panait.oss@gmail.com>
Closes: https://lore.kernel.org/r/aLSnCc9Ws5L9y+8X@gcabiddu-mobl.ger.corp.intel.com
Fixes: 4bc7f7b687a2 ("crypto: sha512 - Use same state format as legacy drivers")
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
---
 crypto/sha512.c | 71 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/crypto/sha512.c b/crypto/sha512.c
index fb1c520978ef3..d320fe53913fa 100644
--- a/crypto/sha512.c
+++ b/crypto/sha512.c
@@ -48,10 +48,23 @@ static int __crypto_sha512_import(struct __sha512_ctx *ctx, const void *in)
 	p += sizeof(*ctx);
 	ctx->bytecount_lo += *p;
 	return 0;
 }
 
+static int __crypto_sha512_export_core(const struct __sha512_ctx *ctx,
+				       void *out)
+{
+	memcpy(out, ctx, offsetof(struct __sha512_ctx, buf));
+	return 0;
+}
+
+static int __crypto_sha512_import_core(struct __sha512_ctx *ctx, const void *in)
+{
+	memcpy(ctx, in, offsetof(struct __sha512_ctx, buf));
+	return 0;
+}
+
 /* SHA-384 */
 
 const u8 sha384_zero_message_hash[SHA384_DIGEST_SIZE] = {
 	0x38, 0xb0, 0x60, 0xa7, 0x51, 0xac, 0x96, 0x38,
 	0x4c, 0xd9, 0x32, 0x7e, 0xb1, 0xb1, 0xe3, 0x6a,
@@ -98,10 +111,20 @@ static int crypto_sha384_export(struct shash_desc *desc, void *out)
 static int crypto_sha384_import(struct shash_desc *desc, const void *in)
 {
 	return __crypto_sha512_import(&SHA384_CTX(desc)->ctx, in);
 }
 
+static int crypto_sha384_export_core(struct shash_desc *desc, void *out)
+{
+	return __crypto_sha512_export_core(&SHA384_CTX(desc)->ctx, out);
+}
+
+static int crypto_sha384_import_core(struct shash_desc *desc, const void *in)
+{
+	return __crypto_sha512_import_core(&SHA384_CTX(desc)->ctx, in);
+}
+
 /* SHA-512 */
 
 const u8 sha512_zero_message_hash[SHA512_DIGEST_SIZE] = {
 	0xcf, 0x83, 0xe1, 0x35, 0x7e, 0xef, 0xb8, 0xbd,
 	0xf1, 0x54, 0x28, 0x50, 0xd6, 0x6d, 0x80, 0x07,
@@ -150,10 +173,20 @@ static int crypto_sha512_export(struct shash_desc *desc, void *out)
 static int crypto_sha512_import(struct shash_desc *desc, const void *in)
 {
 	return __crypto_sha512_import(&SHA512_CTX(desc)->ctx, in);
 }
 
+static int crypto_sha512_export_core(struct shash_desc *desc, void *out)
+{
+	return __crypto_sha512_export_core(&SHA512_CTX(desc)->ctx, out);
+}
+
+static int crypto_sha512_import_core(struct shash_desc *desc, const void *in)
+{
+	return __crypto_sha512_import_core(&SHA512_CTX(desc)->ctx, in);
+}
+
 /* HMAC-SHA384 */
 
 #define HMAC_SHA384_KEY(tfm) ((struct hmac_sha384_key *)crypto_shash_ctx(tfm))
 #define HMAC_SHA384_CTX(desc) ((struct hmac_sha384_ctx *)shash_desc_ctx(desc))
 
@@ -202,10 +235,25 @@ static int crypto_hmac_sha384_import(struct shash_desc *desc, const void *in)
 
 	ctx->ctx.ostate = HMAC_SHA384_KEY(desc->tfm)->key.ostate;
 	return __crypto_sha512_import(&ctx->ctx.sha_ctx, in);
 }
 
+static int crypto_hmac_sha384_export_core(struct shash_desc *desc, void *out)
+{
+	return __crypto_sha512_export_core(&HMAC_SHA384_CTX(desc)->ctx.sha_ctx,
+					   out);
+}
+
+static int crypto_hmac_sha384_import_core(struct shash_desc *desc,
+					  const void *in)
+{
+	struct hmac_sha384_ctx *ctx = HMAC_SHA384_CTX(desc);
+
+	ctx->ctx.ostate = HMAC_SHA384_KEY(desc->tfm)->key.ostate;
+	return __crypto_sha512_import_core(&ctx->ctx.sha_ctx, in);
+}
+
 /* HMAC-SHA512 */
 
 #define HMAC_SHA512_KEY(tfm) ((struct hmac_sha512_key *)crypto_shash_ctx(tfm))
 #define HMAC_SHA512_CTX(desc) ((struct hmac_sha512_ctx *)shash_desc_ctx(desc))
 
@@ -254,10 +302,25 @@ static int crypto_hmac_sha512_import(struct shash_desc *desc, const void *in)
 
 	ctx->ctx.ostate = HMAC_SHA512_KEY(desc->tfm)->key.ostate;
 	return __crypto_sha512_import(&ctx->ctx.sha_ctx, in);
 }
 
+static int crypto_hmac_sha512_export_core(struct shash_desc *desc, void *out)
+{
+	return __crypto_sha512_export_core(&HMAC_SHA512_CTX(desc)->ctx.sha_ctx,
+					   out);
+}
+
+static int crypto_hmac_sha512_import_core(struct shash_desc *desc,
+					  const void *in)
+{
+	struct hmac_sha512_ctx *ctx = HMAC_SHA512_CTX(desc);
+
+	ctx->ctx.ostate = HMAC_SHA512_KEY(desc->tfm)->key.ostate;
+	return __crypto_sha512_import_core(&ctx->ctx.sha_ctx, in);
+}
+
 /* Algorithm definitions */
 
 static struct shash_alg algs[] = {
 	{
 		.base.cra_name		= "sha384",
@@ -270,10 +333,12 @@ static struct shash_alg algs[] = {
 		.update			= crypto_sha384_update,
 		.final			= crypto_sha384_final,
 		.digest			= crypto_sha384_digest,
 		.export			= crypto_sha384_export,
 		.import			= crypto_sha384_import,
+		.export_core		= crypto_sha384_export_core,
+		.import_core		= crypto_sha384_import_core,
 		.descsize		= sizeof(struct sha384_ctx),
 		.statesize		= SHA512_SHASH_STATE_SIZE,
 	},
 	{
 		.base.cra_name		= "sha512",
@@ -286,10 +351,12 @@ static struct shash_alg algs[] = {
 		.update			= crypto_sha512_update,
 		.final			= crypto_sha512_final,
 		.digest			= crypto_sha512_digest,
 		.export			= crypto_sha512_export,
 		.import			= crypto_sha512_import,
+		.export_core		= crypto_sha512_export_core,
+		.import_core		= crypto_sha512_import_core,
 		.descsize		= sizeof(struct sha512_ctx),
 		.statesize		= SHA512_SHASH_STATE_SIZE,
 	},
 	{
 		.base.cra_name		= "hmac(sha384)",
@@ -304,10 +371,12 @@ static struct shash_alg algs[] = {
 		.update			= crypto_hmac_sha384_update,
 		.final			= crypto_hmac_sha384_final,
 		.digest			= crypto_hmac_sha384_digest,
 		.export			= crypto_hmac_sha384_export,
 		.import			= crypto_hmac_sha384_import,
+		.export_core		= crypto_hmac_sha384_export_core,
+		.import_core		= crypto_hmac_sha384_import_core,
 		.descsize		= sizeof(struct hmac_sha384_ctx),
 		.statesize		= SHA512_SHASH_STATE_SIZE,
 	},
 	{
 		.base.cra_name		= "hmac(sha512)",
@@ -322,10 +391,12 @@ static struct shash_alg algs[] = {
 		.update			= crypto_hmac_sha512_update,
 		.final			= crypto_hmac_sha512_final,
 		.digest			= crypto_hmac_sha512_digest,
 		.export			= crypto_hmac_sha512_export,
 		.import			= crypto_hmac_sha512_import,
+		.export_core		= crypto_hmac_sha512_export_core,
+		.import_core		= crypto_hmac_sha512_import_core,
 		.descsize		= sizeof(struct hmac_sha512_ctx),
 		.statesize		= SHA512_SHASH_STATE_SIZE,
 	},
 };
 
-- 
2.50.1