[v7,04/11] crypto: qce: skcipher: Return unsupported if any three keys are same for DES3 algorithms
diff mbox series

Message ID 20210211200128.2886388-5-thara.gopinath@linaro.org
State Accepted
Commit 42f730a47beee3b8df9a55ed8a3009eb0fe5bd3f
Headers show
Series
  • Regression fixes/clean ups in the Qualcomm crypto engine driver
Related show

Commit Message

Thara Gopinath Feb. 11, 2021, 8:01 p.m. UTC
Return unsupported if any three keys are same for DES3 algorithms
since CE does not support this and the operation causes the engine to
hang.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
---

v6->v7:
	- Fixed sparse warning in patch 4 as pointed out by Herbert Xu.
	  This means the checking if any two keys are same for triple
	  des algorithms has been reverted back to using conditional OR
	  instead of using bitwise OR.

 drivers/crypto/qce/skcipher.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

Patch
diff mbox series

diff --git a/drivers/crypto/qce/skcipher.c b/drivers/crypto/qce/skcipher.c
index 12955dcd53dd..8aeb741ca5a3 100644
--- a/drivers/crypto/qce/skcipher.c
+++ b/drivers/crypto/qce/skcipher.c
@@ -221,12 +221,27 @@  static int qce_des3_setkey(struct crypto_skcipher *ablk, const u8 *key,
 			   unsigned int keylen)
 {
 	struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(ablk);
+	u32 _key[6];
 	int err;
 
 	err = verify_skcipher_des3_key(ablk, key);
 	if (err)
 		return err;
 
+	/*
+	 * The crypto engine does not support any two keys
+	 * being the same for triple des algorithms. The
+	 * verify_skcipher_des3_key does not check for all the
+	 * below conditions. Return -ENOKEY in case any two keys
+	 * are the same. Revisit to see if a fallback cipher
+	 * is needed to handle this condition.
+	 */
+	memcpy(_key, key, DES3_EDE_KEY_SIZE);
+	if (!((_key[0] ^ _key[2]) | (_key[1] ^ _key[3])) ||
+	    !((_key[2] ^ _key[4]) | (_key[3] ^ _key[5])) ||
+	    !((_key[0] ^ _key[4]) | (_key[1] ^ _key[5])))
+		return -ENOKEY;
+
 	ctx->enc_keylen = keylen;
 	memcpy(ctx->enc_key, key, keylen);
 	return 0;