[CRYPTO] aead: Make authsize a run-time parameter
[linux-3.10.git] / crypto / aead.c
index 84a3501fb478bf8bb9d12c2586e925c59eb46135..f23c2b0ee009915f6faeb9531436151aec5f9727 100644 (file)
@@ -53,6 +53,24 @@ static int setkey(struct crypto_aead *tfm, const u8 *key, unsigned int keylen)
        return aead->setkey(tfm, key, keylen);
 }
 
+int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
+{
+       int err;
+
+       if (authsize > crypto_aead_alg(tfm)->maxauthsize)
+               return -EINVAL;
+
+       if (crypto_aead_alg(tfm)->setauthsize) {
+               err = crypto_aead_alg(tfm)->setauthsize(tfm, authsize);
+               if (err)
+                       return err;
+       }
+
+       crypto_aead_crt(tfm)->authsize = authsize;
+       return 0;
+}
+EXPORT_SYMBOL_GPL(crypto_aead_setauthsize);
+
 static unsigned int crypto_aead_ctxsize(struct crypto_alg *alg, u32 type,
                                        u32 mask)
 {
@@ -64,14 +82,14 @@ static int crypto_init_aead_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
        struct aead_alg *alg = &tfm->__crt_alg->cra_aead;
        struct aead_tfm *crt = &tfm->crt_aead;
 
-       if (max(alg->authsize, alg->ivsize) > PAGE_SIZE / 8)
+       if (max(alg->maxauthsize, alg->ivsize) > PAGE_SIZE / 8)
                return -EINVAL;
 
        crt->setkey = setkey;
        crt->encrypt = alg->encrypt;
        crt->decrypt = alg->decrypt;
        crt->ivsize = alg->ivsize;
-       crt->authsize = alg->authsize;
+       crt->authsize = alg->maxauthsize;
 
        return 0;
 }
@@ -85,7 +103,7 @@ static void crypto_aead_show(struct seq_file *m, struct crypto_alg *alg)
        seq_printf(m, "type         : aead\n");
        seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
        seq_printf(m, "ivsize       : %u\n", aead->ivsize);
-       seq_printf(m, "authsize     : %u\n", aead->authsize);
+       seq_printf(m, "maxauthsize  : %u\n", aead->maxauthsize);
 }
 
 const struct crypto_type crypto_aead_type = {