crypto: sha256_generic - Add export/import support

This patch adds export/import support to sha256_generic.  The exported
type is defined by struct sha256_state, which is basically the entire
descriptor state of sha256_generic.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 25 insertions, 12 deletions

diff --git a/crypto/sha256_generic.c b/crypto/sha256_generic.c
index e58c71bdf333..c48459ebf05b 100644
--- a/crypto/sha256_generic.c
+++ b/crypto/sha256_generic.c
@@ -25,12 +25,6 @@
 #include <crypto/sha.h>
 #include <asm/byteorder.h>
 
-struct sha256_ctx {
-        u64 count;
-        u32 state[8];
-        u8 buf[128];
-};
-
 static inline u32 Ch(u32 x, u32 y, u32 z)
 {
         return z ^ (x & (y ^ z));
@@ -222,7 +216,7 @@ static void sha256_transform(u32 *state, const u8 *input)
 
 static int sha224_init(struct shash_desc *desc)
 {
-        struct sha256_ctx *sctx = shash_desc_ctx(desc);
+        struct sha256_state *sctx = shash_desc_ctx(desc);
         sctx->state[0] = SHA224_H0;
         sctx->state[1] = SHA224_H1;
         sctx->state[2] = SHA224_H2;
@@ -238,7 +232,7 @@ static int sha224_init(struct shash_desc *desc)
 
 static int sha256_init(struct shash_desc *desc)
 {
-        struct sha256_ctx *sctx = shash_desc_ctx(desc);
+        struct sha256_state *sctx = shash_desc_ctx(desc);
         sctx->state[0] = SHA256_H0;
         sctx->state[1] = SHA256_H1;
         sctx->state[2] = SHA256_H2;
@@ -255,7 +249,7 @@ static int sha256_init(struct shash_desc *desc)
 static int sha256_update(struct shash_desc *desc, const u8 *data,
                           unsigned int len)
 {
-        struct sha256_ctx *sctx = shash_desc_ctx(desc);
+        struct sha256_state *sctx = shash_desc_ctx(desc);
         unsigned int partial, done;
         const u8 *src;
 
@@ -286,7 +280,7 @@ static int sha256_update(struct shash_desc *desc, const u8 *data,
 
 static int sha256_final(struct shash_desc *desc, u8 *out)
 {
-        struct sha256_ctx *sctx = shash_desc_ctx(desc);
+        struct sha256_state *sctx = shash_desc_ctx(desc);
         __be32 *dst = (__be32 *)out;
         __be64 bits;
         unsigned int index, pad_len;
@@ -326,12 +320,31 @@ static int sha224_final(struct shash_desc *desc, u8 *hash)
         return 0;
 }
 
+static int sha256_export(struct shash_desc *desc, void *out)
+{
+        struct sha256_state *sctx = shash_desc_ctx(desc);
+
+        memcpy(out, sctx, sizeof(*sctx));
+        return 0;
+}
+
+static int sha256_import(struct shash_desc *desc, const void *in)
+{
+        struct sha256_state *sctx = shash_desc_ctx(desc);
+
+        memcpy(sctx, in, sizeof(*sctx));
+        return 0;
+}
+
 static struct shash_alg sha256 = {
         .digestsize     =       SHA256_DIGEST_SIZE,
         .init           =       sha256_init,
         .update         =       sha256_update,
         .final          =       sha256_final,
-        .descsize       =       sizeof(struct sha256_ctx),
+        .export         =       sha256_export,
+        .import         =       sha256_import,
+        .descsize       =       sizeof(struct sha256_state),
+        .statesize      =       sizeof(struct sha256_state),
         .base           =       {
                 .cra_name       =       "sha256",
                 .cra_driver_name=       "sha256-generic",
@@ -346,7 +359,7 @@ static struct shash_alg sha224 = {
         .init           =       sha224_init,
         .update         =       sha256_update,
         .final          =       sha224_final,
-        .descsize       =       sizeof(struct sha256_ctx),
+        .descsize       =       sizeof(struct sha256_state),
         .base           =       {
                 .cra_name       =       "sha224",
                 .cra_driver_name=       "sha224-generic",