staging/rtl8192e: switch to RC4 library interface

Switch to the ARC4 library interface, to remove the pointless
dependency on the skcipher API, from which we will hopefully be
able to drop ecb(arc4) skcipher support.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 12 insertions, 58 deletions

diff --git a/drivers/staging/rtl8192e/rtllib_crypt_tkip.c b/drivers/staging/rtl8192e/rtllib_crypt_tkip.c
index 8d2a58e706d5..8c2ff37b2d3a 100644
--- a/drivers/staging/rtl8192e/rtllib_crypt_tkip.c
+++ b/drivers/staging/rtl8192e/rtllib_crypt_tkip.c
@@ -5,8 +5,9 @@
  * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi>
  */
 
+#include <crypto/arc4.h>
 #include <crypto/hash.h>
-#include <crypto/skcipher.h>
+#include <linux/fips.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
@@ -16,7 +17,6 @@
 #include <linux/if_ether.h>
 #include <linux/if_arp.h>
 #include <linux/string.h>
-#include <linux/scatterlist.h>
 #include <linux/crc32.h>
 #include <linux/etherdevice.h>
 
@@ -45,9 +45,9 @@ struct rtllib_tkip_data {
 	u32 dot11RSNAStatsTKIPLocalMICFailures;
 
 	int key_idx;
-	struct crypto_sync_skcipher *rx_tfm_arc4;
+	struct arc4_ctx rx_ctx_arc4;
+	struct arc4_ctx tx_ctx_arc4;
 	struct crypto_shash *rx_tfm_michael;
-	struct crypto_sync_skcipher *tx_tfm_arc4;
 	struct crypto_shash *tx_tfm_michael;
 	/* scratch buffers for virt_to_page() (crypto API) */
 	u8 rx_hdr[16];
@@ -58,16 +58,13 @@ static void *rtllib_tkip_init(int key_idx)
 {
 	struct rtllib_tkip_data *priv;
 
+	if (fips_enabled)
+		return NULL;
+
 	priv = kzalloc(sizeof(*priv), GFP_ATOMIC);
 	if (priv == NULL)
 		goto fail;
 	priv->key_idx = key_idx;
-	priv->tx_tfm_arc4 = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->tx_tfm_arc4)) {
-		pr_debug("Could not allocate crypto API arc4\n");
-		priv->tx_tfm_arc4 = NULL;
-		goto fail;
-	}
 
 	priv->tx_tfm_michael = crypto_alloc_shash("michael_mic", 0, 0);
 	if (IS_ERR(priv->tx_tfm_michael)) {
@@ -76,13 +73,6 @@ static void *rtllib_tkip_init(int key_idx)
 		goto fail;
 	}
 
-	priv->rx_tfm_arc4 = crypto_alloc_sync_skcipher("ecb(arc4)", 0, 0);
-	if (IS_ERR(priv->rx_tfm_arc4)) {
-		pr_debug("Could not allocate crypto API arc4\n");
-		priv->rx_tfm_arc4 = NULL;
-		goto fail;
-	}
-
 	priv->rx_tfm_michael = crypto_alloc_shash("michael_mic", 0, 0);
 	if (IS_ERR(priv->rx_tfm_michael)) {
 		pr_debug("Could not allocate crypto API michael_mic\n");
@@ -94,9 +84,7 @@ static void *rtllib_tkip_init(int key_idx)
 fail:
 	if (priv) {
 		crypto_free_shash(priv->tx_tfm_michael);
-		crypto_free_sync_skcipher(priv->tx_tfm_arc4);
 		crypto_free_shash(priv->rx_tfm_michael);
-		crypto_free_sync_skcipher(priv->rx_tfm_arc4);
 		kfree(priv);
 	}
 
@@ -110,11 +98,9 @@ static void rtllib_tkip_deinit(void *priv)
 
 	if (_priv) {
 		crypto_free_shash(_priv->tx_tfm_michael);
-		crypto_free_sync_skcipher(_priv->tx_tfm_arc4);
 		crypto_free_shash(_priv->rx_tfm_michael);
-		crypto_free_sync_skcipher(_priv->rx_tfm_arc4);
 	}
-	kfree(priv);
+	kzfree(priv);
 }
 
 
@@ -289,7 +275,6 @@ static int rtllib_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	int ret = 0;
 	u8 rc4key[16],  *icv;
 	u32 crc;
-	struct scatterlist sg;
 
 	if (skb_headroom(skb) < 8 || skb_tailroom(skb) < 4 ||
 	    skb->len < hdr_len)
@@ -331,8 +316,6 @@ static int rtllib_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	*pos++ = (tkey->tx_iv32 >> 24) & 0xff;
 
 	if (!tcb_desc->bHwSec) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, tkey->tx_tfm_arc4);
-
 		icv = skb_put(skb, 4);
 		crc = ~crc32_le(~0, pos, len);
 		icv[0] = crc;
@@ -340,15 +323,8 @@ static int rtllib_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
 		icv[2] = crc >> 16;
 		icv[3] = crc >> 24;
 
-		sg_init_one(&sg, pos, len+4);
-
-
-		crypto_sync_skcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16);
-		skcipher_request_set_sync_tfm(req, tkey->tx_tfm_arc4);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, len + 4, NULL);
-		ret = crypto_skcipher_encrypt(req);
-		skcipher_request_zero(req);
+		arc4_setkey(&tkey->tx_ctx_arc4, rc4key, 16);
+		arc4_crypt(&tkey->tx_ctx_arc4, pos, pos, len + 4);
 	}
 
 	tkey->tx_iv16++;
@@ -376,9 +352,7 @@ static int rtllib_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	u8 rc4key[16];
 	u8 icv[4];
 	u32 crc;
-	struct scatterlist sg;
 	int plen;
-	int err;
 
 	if (skb->len < hdr_len + 8 + 4)
 		return -1;
@@ -414,8 +388,6 @@ static int rtllib_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 	pos += 8;
 
 	if (!tcb_desc->bHwSec || (skb->cb[0] == 1)) {
-		SYNC_SKCIPHER_REQUEST_ON_STACK(req, tkey->rx_tfm_arc4);
-
 		if ((iv32 < tkey->rx_iv32 ||
 		    (iv32 == tkey->rx_iv32 && iv16 <= tkey->rx_iv16)) &&
 		    tkey->initialized) {
@@ -439,22 +411,8 @@ static int rtllib_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
 
 		plen = skb->len - hdr_len - 12;
 
-		sg_init_one(&sg, pos, plen+4);
-
-		crypto_sync_skcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16);
-		skcipher_request_set_sync_tfm(req, tkey->rx_tfm_arc4);
-		skcipher_request_set_callback(req, 0, NULL, NULL);
-		skcipher_request_set_crypt(req, &sg, &sg, plen + 4, NULL);
-		err = crypto_skcipher_decrypt(req);
-		skcipher_request_zero(req);
-		if (err) {
-			if (net_ratelimit()) {
-				netdev_dbg(skb->dev,
-					   "Failed to decrypt received packet from %pM\n",
-					   hdr->addr2);
-			}
-			return -7;
-		}
+		arc4_setkey(&tkey->rx_ctx_arc4, rc4key, 16);
+		arc4_crypt(&tkey->rx_ctx_arc4, pos, pos, plen + 4);
 
 		crc = ~crc32_le(~0, pos, plen);
 		icv[0] = crc;
@@ -657,17 +615,13 @@ static int rtllib_tkip_set_key(void *key, int len, u8 *seq, void *priv)
 	struct rtllib_tkip_data *tkey = priv;
 	int keyidx;
 	struct crypto_shash *tfm = tkey->tx_tfm_michael;
-	struct crypto_sync_skcipher *tfm2 = tkey->tx_tfm_arc4;
 	struct crypto_shash *tfm3 = tkey->rx_tfm_michael;
-	struct crypto_sync_skcipher *tfm4 = tkey->rx_tfm_arc4;
 
 	keyidx = tkey->key_idx;
 	memset(tkey, 0, sizeof(*tkey));
 	tkey->key_idx = keyidx;
 	tkey->tx_tfm_michael = tfm;
-	tkey->tx_tfm_arc4 = tfm2;
 	tkey->rx_tfm_michael = tfm3;
-	tkey->rx_tfm_arc4 = tfm4;
 
 	if (len == TKIP_KEY_LEN) {
 		memcpy(tkey->key, key, TKIP_KEY_LEN);