crypto: rsa - RSA padding algorithm

This patch adds PKCS#1 v1.5 standard RSA padding as a separate template.
This way an RSA cipher with padding can be obtained by instantiating
"pkcs1pad(rsa)".  The reason for adding this is that RSA is almost
never used without this padding (or OAEP) so it will be needed for
either certificate work in the kernel or the userspace, and I also hear
that it is likely implemented by hardware RSA in which case hardware
implementations of the whole of pkcs1pad(rsa) can be provided.

Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 15 insertions, 1 deletions

diff --git a/crypto/rsa.c b/crypto/rsa.c
index 58aad69..77d737f 100644
--- a/crypto/rsa.c
+++ b/crypto/rsa.c
@@ -13,6 +13,7 @@
 #include <crypto/internal/rsa.h>
 #include <crypto/internal/akcipher.h>
 #include <crypto/akcipher.h>
+#include <crypto/algapi.h>
 
 /*
  * RSAEP function [RFC3447 sec 5.1.1]
@@ -315,11 +316,24 @@ static struct akcipher_alg rsa = {
 
 static int rsa_init(void)
 {
-	return crypto_register_akcipher(&rsa);
+	int err;
+
+	err = crypto_register_akcipher(&rsa);
+	if (err)
+		return err;
+
+	err = crypto_register_template(&rsa_pkcs1pad_tmpl);
+	if (err) {
+		crypto_unregister_akcipher(&rsa);
+		return err;
+	}
+
+	return 0;
 }
 
 static void rsa_exit(void)
 {
+	crypto_unregister_template(&rsa_pkcs1pad_tmpl);
 	crypto_unregister_akcipher(&rsa);
 }