crypto: ccp - Allow for selective disablement of crypto API algorithms
authorTom Lendacky <thomas.lendacky@amd.com>
Fri, 24 Jan 2014 22:17:56 +0000 (16:17 -0600)
committerHerbert Xu <herbert@gondor.apana.org.au>
Sun, 9 Feb 2014 01:59:15 +0000 (09:59 +0800)
Introduce module parameters that allow for disabling of a
crypto algorithm by not registering the algorithm with the
crypto API.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
drivers/crypto/ccp/ccp-crypto-main.c

index 2636f04..b3f22b0 100644 (file)
@@ -11,6 +11,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/moduleparam.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/ccp.h>
@@ -24,6 +25,14 @@ MODULE_LICENSE("GPL");
 MODULE_VERSION("1.0.0");
 MODULE_DESCRIPTION("AMD Cryptographic Coprocessor crypto API support");
 
+static unsigned int aes_disable;
+module_param(aes_disable, uint, 0444);
+MODULE_PARM_DESC(aes_disable, "Disable use of AES - any non-zero value");
+
+static unsigned int sha_disable;
+module_param(sha_disable, uint, 0444);
+MODULE_PARM_DESC(sha_disable, "Disable use of SHA - any non-zero value");
+
 
 /* List heads for the supported algorithms */
 static LIST_HEAD(hash_algs);
@@ -337,21 +346,25 @@ static int ccp_register_algs(void)
 {
        int ret;
 
-       ret = ccp_register_aes_algs(&cipher_algs);
-       if (ret)
-               return ret;
+       if (!aes_disable) {
+               ret = ccp_register_aes_algs(&cipher_algs);
+               if (ret)
+                       return ret;
 
-       ret = ccp_register_aes_cmac_algs(&hash_algs);
-       if (ret)
-               return ret;
+               ret = ccp_register_aes_cmac_algs(&hash_algs);
+               if (ret)
+                       return ret;
 
-       ret = ccp_register_aes_xts_algs(&cipher_algs);
-       if (ret)
-               return ret;
+               ret = ccp_register_aes_xts_algs(&cipher_algs);
+               if (ret)
+                       return ret;
+       }
 
-       ret = ccp_register_sha_algs(&hash_algs);
-       if (ret)
-               return ret;
+       if (!sha_disable) {
+               ret = ccp_register_sha_algs(&hash_algs);
+               if (ret)
+                       return ret;
+       }
 
        return 0;
 }