crypto: atmel-sha - fix algorihtm registration

This patch implements the missing .import() and .export() mandatory
hooks for asynchronous hash algorithms. It also sets the relevant, non
zero, value for the .statesize field when declaring the supported SHA
algorithms. Indeed a zero value of .statesize prevents the algorithm from
being registered.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/crypto/atmel-sha.c b/drivers/crypto/atmel-sha.c
index da4c305..63b09e0 100644
--- a/drivers/crypto/atmel-sha.c
+++ b/drivers/crypto/atmel-sha.c
@@ -66,7 +66,7 @@
 #define SHA_OP_UPDATE	1
 #define SHA_OP_FINAL	2
 
-#define SHA_BUFFER_LEN		PAGE_SIZE
+#define SHA_BUFFER_LEN		(PAGE_SIZE / 16)
 
 #define ATMEL_SHA_DMA_THRESHOLD		56
 
@@ -80,6 +80,17 @@
 
 struct atmel_sha_dev;
 
+/*
+ * .statesize = sizeof(struct atmel_sha_state) must be <= PAGE_SIZE / 8 as
+ * tested by the ahash_prepare_alg() function.
+ */
+struct atmel_sha_state {
+	u8	digest[SHA512_DIGEST_SIZE];
+	u8	buffer[SHA_BUFFER_LEN];
+	u64	digcnt[2];
+	size_t	bufcnt;
+};
+
 struct atmel_sha_reqctx {
 	struct atmel_sha_dev	*dd;
 	unsigned long	flags;
@@ -1033,6 +1044,39 @@
 	return atmel_sha_init(req) ?: atmel_sha_finup(req);
 }
 
+
+static int atmel_sha_export(struct ahash_request *req, void *out)
+{
+	const struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
+	struct atmel_sha_state state;
+
+	memcpy(state.digest, ctx->digest, SHA512_DIGEST_SIZE);
+	memcpy(state.buffer, ctx->buffer, ctx->bufcnt);
+	state.bufcnt = ctx->bufcnt;
+	state.digcnt[0] = ctx->digcnt[0];
+	state.digcnt[1] = ctx->digcnt[1];
+
+	/* out might be unaligned. */
+	memcpy(out, &state, sizeof(state));
+	return 0;
+}
+
+static int atmel_sha_import(struct ahash_request *req, const void *in)
+{
+	struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
+	struct atmel_sha_state state;
+
+	/* in might be unaligned. */
+	memcpy(&state, in, sizeof(state));
+
+	memcpy(ctx->digest, state.digest, SHA512_DIGEST_SIZE);
+	memcpy(ctx->buffer, state.buffer, state.bufcnt);
+	ctx->bufcnt = state.bufcnt;
+	ctx->digcnt[0] = state.digcnt[0];
+	ctx->digcnt[1] = state.digcnt[1];
+	return 0;
+}
+
 static int atmel_sha_cra_init(struct crypto_tfm *tfm)
 {
 	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
@@ -1049,8 +1093,11 @@
 	.final		= atmel_sha_final,
 	.finup		= atmel_sha_finup,
 	.digest		= atmel_sha_digest,
+	.export		= atmel_sha_export,
+	.import		= atmel_sha_import,
 	.halg = {
 		.digestsize	= SHA1_DIGEST_SIZE,
+		.statesize	= sizeof(struct atmel_sha_state),
 		.base	= {
 			.cra_name		= "sha1",
 			.cra_driver_name	= "atmel-sha1",
@@ -1070,8 +1117,11 @@
 	.final		= atmel_sha_final,
 	.finup		= atmel_sha_finup,
 	.digest		= atmel_sha_digest,
+	.export		= atmel_sha_export,
+	.import		= atmel_sha_import,
 	.halg = {
 		.digestsize	= SHA256_DIGEST_SIZE,
+		.statesize	= sizeof(struct atmel_sha_state),
 		.base	= {
 			.cra_name		= "sha256",
 			.cra_driver_name	= "atmel-sha256",
@@ -1093,8 +1143,11 @@
 	.final		= atmel_sha_final,
 	.finup		= atmel_sha_finup,
 	.digest		= atmel_sha_digest,
+	.export		= atmel_sha_export,
+	.import		= atmel_sha_import,
 	.halg = {
 		.digestsize	= SHA224_DIGEST_SIZE,
+		.statesize	= sizeof(struct atmel_sha_state),
 		.base	= {
 			.cra_name		= "sha224",
 			.cra_driver_name	= "atmel-sha224",
@@ -1116,8 +1169,11 @@
 	.final		= atmel_sha_final,
 	.finup		= atmel_sha_finup,
 	.digest		= atmel_sha_digest,
+	.export		= atmel_sha_export,
+	.import		= atmel_sha_import,
 	.halg = {
 		.digestsize	= SHA384_DIGEST_SIZE,
+		.statesize	= sizeof(struct atmel_sha_state),
 		.base	= {
 			.cra_name		= "sha384",
 			.cra_driver_name	= "atmel-sha384",
@@ -1137,8 +1193,11 @@
 	.final		= atmel_sha_final,
 	.finup		= atmel_sha_finup,
 	.digest		= atmel_sha_digest,
+	.export		= atmel_sha_export,
+	.import		= atmel_sha_import,
 	.halg = {
 		.digestsize	= SHA512_DIGEST_SIZE,
+		.statesize	= sizeof(struct atmel_sha_state),
 		.base	= {
 			.cra_name		= "sha512",
 			.cra_driver_name	= "atmel-sha512",