crypto: sahara - remove FLAGS_NEW_KEY logic

Remove the FLAGS_NEW_KEY logic as it has the following issues:
- the wrong key may end up being used when there are multiple data streams:
       t1            t2
    setkey()
    encrypt()
                   setkey()
                   encrypt()

    encrypt() <--- key from t2 is used
- switching between encryption and decryption with the same key is not
  possible, as the hdr flags are only updated when a new setkey() is
  performed

With this change, the key is always sent along with the cryptdata when
performing encryption/decryption operations.

Fixes: 5de88752 ("crypto: sahara - Add driver for SAHARA2 accelerator.")
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/sahara.c

@@ -43,7 +43,6 @@
 #define FLAGS_MODE_MASK		0x000f
 #define FLAGS_ENCRYPT		BIT(0)
 #define FLAGS_CBC		BIT(1)
-#define FLAGS_NEW_KEY		BIT(3)
 
 #define SAHARA_HDR_BASE			0x00800000
 #define SAHARA_HDR_SKHA_ALG_AES	0
@@ -141,8 +140,6 @@ struct sahara_hw_link {
 };
 
 struct sahara_ctx {
-	unsigned long flags;
-
 	/* AES-specific context */
 	int keylen;
 	u8 key[AES_KEYSIZE_128];
@@ -447,26 +444,22 @@ static int sahara_hw_descriptor_create(struct sahara_dev *dev)
 	int i, j;
 	int idx = 0;
 
-	/* Copy new key if necessary */
-	if (ctx->flags & FLAGS_NEW_KEY) {
-		memcpy(dev->key_base, ctx->key, ctx->keylen);
-		ctx->flags &= ~FLAGS_NEW_KEY;
+	memcpy(dev->key_base, ctx->key, ctx->keylen);
 
-		if (dev->flags & FLAGS_CBC) {
-			dev->hw_desc[idx]->len1 = AES_BLOCK_SIZE;
-			dev->hw_desc[idx]->p1 = dev->iv_phys_base;
-		} else {
-			dev->hw_desc[idx]->len1 = 0;
-			dev->hw_desc[idx]->p1 = 0;
-		}
-		dev->hw_desc[idx]->len2 = ctx->keylen;
-		dev->hw_desc[idx]->p2 = dev->key_phys_base;
-		dev->hw_desc[idx]->next = dev->hw_phys_desc[1];
+	if (dev->flags & FLAGS_CBC) {
+		dev->hw_desc[idx]->len1 = AES_BLOCK_SIZE;
+		dev->hw_desc[idx]->p1 = dev->iv_phys_base;
+	} else {
+		dev->hw_desc[idx]->len1 = 0;
+		dev->hw_desc[idx]->p1 = 0;
+	}
+	dev->hw_desc[idx]->len2 = ctx->keylen;
+	dev->hw_desc[idx]->p2 = dev->key_phys_base;
+	dev->hw_desc[idx]->next = dev->hw_phys_desc[1];
+	dev->hw_desc[idx]->hdr = sahara_aes_key_hdr(dev);
 
-		dev->hw_desc[idx]->hdr = sahara_aes_key_hdr(dev);
+	idx++;
 
-		idx++;
-	}
 
 	dev->nb_in_sg = sg_nents_for_len(dev->in_sg, dev->total);
 	if (dev->nb_in_sg < 0) {
@@ -608,7 +601,6 @@ static int sahara_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
 	/* SAHARA only supports 128bit keys */
 	if (keylen == AES_KEYSIZE_128) {
 		memcpy(ctx->key, key, keylen);
-		ctx->flags |= FLAGS_NEW_KEY;
 		return 0;
 	}