staging: ks7010: removed custom Michael MIC implementation.

Changed the driver to use the kernel's own implementation.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ks7010/Makefile

@@ -1,3 +1,3 @@
 obj-$(CONFIG_KS7010) += ks7010.o
 
-ks7010-y	     := michael_mic.o ks_hostif.o ks_wlan_net.o ks7010_sdio.o
+ks7010-y	:= ks_hostif.o ks_wlan_net.o ks7010_sdio.o

drivers/staging/ks7010/TODO

@@ -27,8 +27,6 @@ Now the TODOs:
 - fix the 'card removal' event when card is inserted when booting
 - check what other upstream wireless mechanisms can be used instead of the
   custom ones here
-- replace custom Michael MIC implementation with the kernel
-  implementation. This task is only required for a *clean* WEXT interface.
 
 Please send any patches to:
 Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ks7010/ks_hostif.c

@@ -6,15 +6,18 @@
  *   Copyright (C) 2009 Renesas Technology Corp.
  */
 
+#include <crypto/hash.h>
 #include <linux/circ_buf.h>
 #include <linux/if_arp.h>
 #include <net/iw_handler.h>
 #include <uapi/linux/llc.h>
 #include "eap_packet.h"
 #include "ks_wlan.h"
-#include "michael_mic.h"
 #include "ks_hostif.h"
 
+#define MICHAEL_MIC_KEY_LEN 8
+#define MICHAEL_MIC_LEN     8
+
 static inline void inc_smeqhead(struct ks_wlan_private *priv)
 {
 	priv->sme_i.qhead = (priv->sme_i.qhead + 1) % SME_EVENT_BUFF_SIZE;
@@ -191,6 +194,68 @@ static u8 read_ie(unsigned char *bp, u8 max, u8 *body)
 	return size;
 }
 
+static int
+michael_mic(u8 *key, u8 *data, unsigned int len, u8 priority, u8 *result)
+{
+	u8 pad_data[4] = { priority, 0, 0, 0 };
+	struct crypto_shash *tfm = NULL;
+	struct shash_desc *desc = NULL;
+	int ret;
+
+	tfm = crypto_alloc_shash("michael_mic", 0, 0);
+	if (IS_ERR(tfm)) {
+		ret = PTR_ERR(tfm);
+		goto err;
+	}
+
+	ret = crypto_shash_setkey(tfm, key, MICHAEL_MIC_KEY_LEN);
+	if (ret < 0)
+		goto err_free_tfm;
+
+	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(tfm), GFP_KERNEL);
+	if (!desc) {
+		ret = -ENOMEM;
+		goto err_free_tfm;
+	}
+
+	desc->tfm = tfm;
+	desc->flags = 0;
+
+	ret = crypto_shash_init(desc);
+	if (ret < 0)
+		goto err_free_desc;
+
+	// Compute the MIC value
+	/*
+	 * IEEE802.11i  page 47
+	 * Figure 43g TKIP MIC processing format
+	 * +--+--+--------+--+----+--+--+--+--+--+--+--+--+
+	 * |6 |6 |1       |3 |M   |1 |1 |1 |1 |1 |1 |1 |1 | Octet
+	 * +--+--+--------+--+----+--+--+--+--+--+--+--+--+
+	 * |DA|SA|Priority|0 |Data|M0|M1|M2|M3|M4|M5|M6|M7|
+	 * +--+--+--------+--+----+--+--+--+--+--+--+--+--+
+	 */
+
+	ret = crypto_shash_update(desc, data, 12);
+	if (ret < 0)
+		goto err_free_desc;
+
+	ret = crypto_shash_update(desc, pad_data, 4);
+	if (ret < 0)
+		goto err_free_desc;
+
+	ret = crypto_shash_finup(desc, data + 12, len - 12, result);
+
+err_free_desc:
+	kzfree(desc);
+
+err_free_tfm:
+	crypto_free_shash(tfm);
+
+err:
+	return ret;
+}
+
 static
 int get_ap_information(struct ks_wlan_private *priv, struct ap_info *ap_info,
 		       struct local_ap *ap)
@@ -273,11 +338,11 @@ int hostif_data_indication_wpa(struct ks_wlan_private *priv,
 {
 	struct ether_hdr *eth_hdr;
 	unsigned short eth_proto;
-	unsigned char recv_mic[8];
+	unsigned char recv_mic[MICHAEL_MIC_LEN];
 	char buf[128];
 	unsigned long now;
 	struct mic_failure *mic_failure;
-	struct michael_mic michael_mic;
+	u8 mic[MICHAEL_MIC_LEN];
 	union iwreq_data wrqu;
 	unsigned int key_index = auth_type - 1;
 	struct wpa_key *key = &priv->wpa.key[key_index];
@@ -300,14 +365,20 @@ int hostif_data_indication_wpa(struct ks_wlan_private *priv,
 		netdev_dbg(priv->net_dev, "TKIP: protocol=%04X: size=%u\n",
 			   eth_proto, priv->rx_size);
 		/* MIC save */
-		memcpy(&recv_mic[0], (priv->rxp) + ((priv->rx_size) - 8), 8);
-		priv->rx_size = priv->rx_size - 8;
+		memcpy(&recv_mic[0],
+		       (priv->rxp) + ((priv->rx_size) - sizeof(recv_mic)),
+		       sizeof(recv_mic));
+		priv->rx_size = priv->rx_size - sizeof(recv_mic);
 		if (auth_type > 0 && auth_type < 4) {	/* auth_type check */
-			michael_mic_function(&michael_mic, key->rx_mic_key,
-					     priv->rxp, priv->rx_size,
-					     0,	michael_mic.result);
+			int ret;
+
+			ret = michael_mic(key->rx_mic_key,
+					  priv->rxp, priv->rx_size,
+					  0, mic);
+			if (ret < 0)
+				return ret;
 		}
-		if (memcmp(michael_mic.result, recv_mic, 8) != 0) {
+		if (memcmp(mic, recv_mic, sizeof(mic)) != 0) {
 			now = jiffies;
 			mic_failure = &priv->wpa.mic_failure;
 			/* MIC FAILURE */
@@ -1002,7 +1073,6 @@ int hostif_data_request(struct ks_wlan_private *priv, struct sk_buff *skb)
 	int result = 0;
 	unsigned short eth_proto;
 	struct ether_hdr *eth_hdr;
-	struct michael_mic michael_mic;
 	unsigned short keyinfo = 0;
 	struct ieee802_1x_hdr *aa1x_hdr;
 	struct wpa_eapol_key *eap_key;
@@ -1109,17 +1179,20 @@ int hostif_data_request(struct ks_wlan_private *priv, struct sk_buff *skb)
 			pp->auth_type = cpu_to_le16(TYPE_AUTH);
 		} else {
 			if (priv->wpa.pairwise_suite == IW_AUTH_CIPHER_TKIP) {
-				michael_mic_function(&michael_mic,
-						     priv->wpa.key[0].tx_mic_key,
-						     &pp->data[0], skb_len,
-						     0,	michael_mic.result);
-				memcpy(p, michael_mic.result, 8);
-				length += 8;
-				skb_len += 8;
-				p += 8;
+				u8 mic[MICHAEL_MIC_LEN];
+
+				ret = michael_mic(priv->wpa.key[0].tx_mic_key,
+						  &pp->data[0], skb_len,
+						  0, mic);
+				if (ret < 0)
+					goto err_kfree;
+
+				memcpy(p, mic, sizeof(mic));
+				length += sizeof(mic);
+				skb_len += sizeof(mic);
+				p += sizeof(mic);
 				pp->auth_type =
 				    cpu_to_le16(TYPE_DATA);
-
 			} else if (priv->wpa.pairwise_suite ==
 				   IW_AUTH_CIPHER_CCMP) {
 				pp->auth_type =