From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Fri, 16 Jan 2015 08:38:17 +0000 (+1100)
Subject: crypto: cts - Weed out non-CBC algorithms
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=988dc0174411ad4b98c173f3d7d25aca9e56cd85;p=linux-beck.git

crypto: cts - Weed out non-CBC algorithms

The cts algorithm as currently implemented assumes the underlying
is a CBC-mode algorithm.  So this patch adds a check for that to
eliminate bogus combinations of cts with non-CBC modes.

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

diff --git a/crypto/cts.c b/crypto/cts.c
index 6a8089c4d4b4..e467ec0acf9f 100644
--- a/crypto/cts.c
+++ b/crypto/cts.c
@@ -290,6 +290,9 @@ static struct crypto_instance *crypto_cts_alloc(struct rtattr **tb)
 	if (!is_power_of_2(alg->cra_blocksize))
 		goto out_put_alg;
 
+	if (strncmp(alg->cra_name, "cbc(", 4))
+		goto out_put_alg;
+
 	inst = crypto_alloc_instance("cts", alg);
 	if (IS_ERR(inst))
 		goto out_put_alg;