[CRYPTO] null: Add null blkcipher algorithm

This patch adds a null blkcipher algorithm called ecb(cipher_null) for
backwards compatibility.  Previously the null algorithm when used by
IPsec copied the data byte by byte.  This new algorithm optimises that
to a straight memcpy which lets us better measure inherent overheads in
our IPsec code.

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

diff --git a/crypto/crypto_null.c b/crypto/crypto_null.c
index 29f77477d701859e5dc34c72035d2c9e39108c67..fc2d2a4d7789141eae7b344f32fe9da9c395e9ca 100644 (file)
--- a/crypto/crypto_null.c
+++ b/crypto/crypto_null.c
@@ -16,15 +16,17 @@
  * (at your option) any later version.
  *
  */
+
+#include <crypto/internal/skcipher.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/mm.h>
-#include <linux/crypto.h>
 #include <linux/string.h>
 
 #define NULL_KEY_SIZE          0
 #define NULL_BLOCK_SIZE                1
 #define NULL_DIGEST_SIZE       0
+#define NULL_IV_SIZE           0
 
 static int null_compress(struct crypto_tfm *tfm, const u8 *src,
                         unsigned int slen, u8 *dst, unsigned int *dlen)
@@ -55,6 +57,26 @@ static void null_crypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
        memcpy(dst, src, NULL_BLOCK_SIZE);
 }
 
+static int skcipher_null_crypt(struct blkcipher_desc *desc,
+                              struct scatterlist *dst,
+                              struct scatterlist *src, unsigned int nbytes)
+{
+       struct blkcipher_walk walk;
+       int err;
+
+       blkcipher_walk_init(&walk, dst, src, nbytes);
+       err = blkcipher_walk_virt(desc, &walk);
+
+       while (walk.nbytes) {
+               if (walk.src.virt.addr != walk.dst.virt.addr)
+                       memcpy(walk.dst.virt.addr, walk.src.virt.addr,
+                              walk.nbytes);
+               err = blkcipher_walk_done(desc, &walk, 0);
+       }
+
+       return err;
+}
+
 static struct crypto_alg compress_null = {
        .cra_name               =       "compress_null",
        .cra_flags              =       CRYPTO_ALG_TYPE_COMPRESS,
@@ -96,6 +118,25 @@ static struct crypto_alg cipher_null = {
        .cia_decrypt            =       null_crypt } }
 };
 
+static struct crypto_alg skcipher_null = {
+       .cra_name               =       "ecb(cipher_null)",
+       .cra_driver_name        =       "ecb-cipher_null",
+       .cra_priority           =       100,
+       .cra_flags              =       CRYPTO_ALG_TYPE_BLKCIPHER,
+       .cra_blocksize          =       NULL_BLOCK_SIZE,
+       .cra_type               =       &crypto_blkcipher_type,
+       .cra_ctxsize            =       0,
+       .cra_module             =       THIS_MODULE,
+       .cra_list               =       LIST_HEAD_INIT(skcipher_null.cra_list),
+       .cra_u                  =       { .blkcipher = {
+       .min_keysize            =       NULL_KEY_SIZE,
+       .max_keysize            =       NULL_KEY_SIZE,
+       .ivsize                 =       NULL_IV_SIZE,
+       .setkey                 =       null_setkey,
+       .encrypt                =       skcipher_null_crypt,
+       .decrypt                =       skcipher_null_crypt } }
+};
+
 MODULE_ALIAS("compress_null");
 MODULE_ALIAS("digest_null");
 MODULE_ALIAS("cipher_null");
@@ -108,27 +149,35 @@ static int __init init(void)
        if (ret < 0)
                goto out;
 
+       ret = crypto_register_alg(&skcipher_null);
+       if (ret < 0)
+               goto out_unregister_cipher;
+
        ret = crypto_register_alg(&digest_null);
-       if (ret < 0) {
-               crypto_unregister_alg(&cipher_null);
-               goto out;
-       }
+       if (ret < 0)
+               goto out_unregister_skcipher;
 
        ret = crypto_register_alg(&compress_null);
-       if (ret < 0) {
-               crypto_unregister_alg(&digest_null);
-               crypto_unregister_alg(&cipher_null);
-               goto out;
-       }
+       if (ret < 0)
+               goto out_unregister_digest;
 
 out:   
        return ret;
+
+out_unregister_digest:
+       crypto_unregister_alg(&digest_null);
+out_unregister_skcipher:
+       crypto_unregister_alg(&skcipher_null);
+out_unregister_cipher:
+       crypto_unregister_alg(&cipher_null);
+       goto out;
 }
 
 static void __exit fini(void)
 {
        crypto_unregister_alg(&compress_null);
        crypto_unregister_alg(&digest_null);
+       crypto_unregister_alg(&skcipher_null);
        crypto_unregister_alg(&cipher_null);
 }
 

diff --git a/include/crypto/internal/skcipher.h b/include/crypto/internal/skcipher.h
index 2071999d4b5ec43a3f1ef889572f505a545f2d96..0053f34764ffaa51a56c882a93731bcb19c754fd 100644 (file)
--- a/include/crypto/internal/skcipher.h
+++ b/include/crypto/internal/skcipher.h
@@ -88,5 +88,10 @@ static inline void skcipher_givcrypt_complete(
        ablkcipher_request_complete(&req->creq, err);
 }
 
+static inline u32 ablkcipher_request_flags(struct ablkcipher_request *req)
+{
+       return req->base.flags;
+}
+
 #endif /* _CRYPTO_INTERNAL_SKCIPHER_H */