crypto: rsa-pkcs1pad - Move key size check to setkey

Rather than repeatedly checking the key size on each operation,
we should be checking it once when the key is set.

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

diff --git a/crypto/rsa-pkcs1pad.c b/crypto/rsa-pkcs1pad.c
index db19284..ebd8514 100644 (file)
--- a/crypto/rsa-pkcs1pad.c
+++ b/crypto/rsa-pkcs1pad.c
@@ -111,40 +111,48 @@ static int pkcs1pad_set_pub_key(struct crypto_akcipher *tfm, const void *key,
                unsigned int keylen)
 {
        struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
-       int err, size;
+       int err;
+
+       ctx->key_size = 0;
 
        err = crypto_akcipher_set_pub_key(ctx->child, key, keylen);
+       if (err)
+               return err;
 
-       if (!err) {
-               /* Find out new modulus size from rsa implementation */
-               size = crypto_akcipher_maxsize(ctx->child);
+       /* Find out new modulus size from rsa implementation */
+       err = crypto_akcipher_maxsize(ctx->child);
+       if (err < 0)
+               return err;
 
-               ctx->key_size = size > 0 ? size : 0;
-               if (size <= 0)
-                       err = size;
-       }
+       if (err > PAGE_SIZE)
+               return -ENOTSUPP;
 
-       return err;
+       ctx->key_size = err;
+       return 0;
 }
 
 static int pkcs1pad_set_priv_key(struct crypto_akcipher *tfm, const void *key,
                unsigned int keylen)
 {
        struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
-       int err, size;
+       int err;
+
+       ctx->key_size = 0;
 
        err = crypto_akcipher_set_priv_key(ctx->child, key, keylen);
+       if (err)
+               return err;
 
-       if (!err) {
-               /* Find out new modulus size from rsa implementation */
-               size = crypto_akcipher_maxsize(ctx->child);
+       /* Find out new modulus size from rsa implementation */
+       err = crypto_akcipher_maxsize(ctx->child);
+       if (err < 0)
+               return err;
 
-               ctx->key_size = size > 0 ? size : 0;
-               if (size <= 0)
-                       err = size;
-       }
+       if (err > PAGE_SIZE)
+               return -ENOTSUPP;
 
-       return err;
+       ctx->key_size = err;
+       return 0;
 }
 
 static int pkcs1pad_get_max_size(struct crypto_akcipher *tfm)
@@ -247,9 +255,6 @@ static int pkcs1pad_encrypt(struct akcipher_request *req)
                return -EOVERFLOW;
        }
 
-       if (ctx->key_size > PAGE_SIZE)
-               return -ENOTSUPP;
-
        /*
         * Replace both input and output to add the padding in the input and
         * the potential missing leading zeros in the output.
@@ -367,9 +372,6 @@ static int pkcs1pad_decrypt(struct akcipher_request *req)
        if (!ctx->key_size || req->src_len != ctx->key_size)
                return -EINVAL;
 
-       if (ctx->key_size > PAGE_SIZE)
-               return -ENOTSUPP;
-
        /* Reuse input buffer, output to a new buffer */
        req_ctx->child_req.src = req->src;
        req_ctx->child_req.src_len = req->src_len;
@@ -420,9 +422,6 @@ static int pkcs1pad_sign(struct akcipher_request *req)
                return -EOVERFLOW;
        }
 
-       if (ctx->key_size > PAGE_SIZE)
-               return -ENOTSUPP;
-
        /*
         * Replace both input and output to add the padding in the input and
         * the potential missing leading zeros in the output.
@@ -560,9 +559,6 @@ static int pkcs1pad_verify(struct akcipher_request *req)
        if (!ctx->key_size || req->src_len < ctx->key_size)
                return -EINVAL;
 
-       if (ctx->key_size > PAGE_SIZE)
-               return -ENOTSUPP;
-
        /* Reuse input buffer, output to a new buffer */
        req_ctx->child_req.src = req->src;
        req_ctx->child_req.src_len = req->src_len;