lib80211: absorb crypto bits from net/ieee80211

These bits are shared already between ipw2x00 and hostap, and could
probably be shared both more cleanly and with other drivers.  This
commit simply relocates the code to lib80211 and adjusts the drivers
appropriately.

Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 784 insertions, 0 deletions

diff --git a/net/wireless/lib80211_crypt_tkip.c b/net/wireless/lib80211_crypt_tkip.c
new file mode 100644
index 000000000000..7e8e22bfed90
--- /dev/null
+++ b/net/wireless/lib80211_crypt_tkip.c
@@ -0,0 +1,784 @@
+/*
+ * lib80211 crypt: host-based TKIP encryption implementation for lib80211
+ *
+ * Copyright (c) 2003-2004, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2008, John W. Linville <linville@tuxdriver.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation. See README and COPYING for
+ * more details.
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/scatterlist.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/mm.h>
+#include <linux/if_ether.h>
+#include <linux/if_arp.h>
+#include <asm/string.h>
+
+#include <linux/wireless.h>
+#include <linux/ieee80211.h>
+#include <net/iw_handler.h>
+
+#include <linux/crypto.h>
+#include <linux/crc32.h>
+
+#include <net/lib80211.h>
+
+MODULE_AUTHOR("Jouni Malinen");
+MODULE_DESCRIPTION("lib80211 crypt: TKIP");
+MODULE_LICENSE("GPL");
+
+struct lib80211_tkip_data {
+#define TKIP_KEY_LEN 32
+	u8 key[TKIP_KEY_LEN];
+	int key_set;
+
+	u32 tx_iv32;
+	u16 tx_iv16;
+	u16 tx_ttak[5];
+	int tx_phase1_done;
+
+	u32 rx_iv32;
+	u16 rx_iv16;
+	u16 rx_ttak[5];
+	int rx_phase1_done;
+	u32 rx_iv32_new;
+	u16 rx_iv16_new;
+
+	u32 dot11RSNAStatsTKIPReplays;
+	u32 dot11RSNAStatsTKIPICVErrors;
+	u32 dot11RSNAStatsTKIPLocalMICFailures;
+
+	int key_idx;
+
+	struct crypto_blkcipher *rx_tfm_arc4;
+	struct crypto_hash *rx_tfm_michael;
+	struct crypto_blkcipher *tx_tfm_arc4;
+	struct crypto_hash *tx_tfm_michael;
+
+	/* scratch buffers for virt_to_page() (crypto API) */
+	u8 rx_hdr[16], tx_hdr[16];
+
+	unsigned long flags;
+};
+
+static unsigned long lib80211_tkip_set_flags(unsigned long flags, void *priv)
+{
+	struct lib80211_tkip_data *_priv = priv;
+	unsigned long old_flags = _priv->flags;
+	_priv->flags = flags;
+	return old_flags;
+}
+
+static unsigned long lib80211_tkip_get_flags(void *priv)
+{
+	struct lib80211_tkip_data *_priv = priv;
+	return _priv->flags;
+}
+
+static void *lib80211_tkip_init(int key_idx)
+{
+	struct lib80211_tkip_data *priv;
+
+	priv = kzalloc(sizeof(*priv), GFP_ATOMIC);
+	if (priv == NULL)
+		goto fail;
+
+	priv->key_idx = key_idx;
+
+	priv->tx_tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0,
+						CRYPTO_ALG_ASYNC);
+	if (IS_ERR(priv->tx_tfm_arc4)) {
+		printk(KERN_DEBUG "lib80211_crypt_tkip: could not allocate "
+		       "crypto API arc4\n");
+		priv->tx_tfm_arc4 = NULL;
+		goto fail;
+	}
+
+	priv->tx_tfm_michael = crypto_alloc_hash("michael_mic", 0,
+						 CRYPTO_ALG_ASYNC);
+	if (IS_ERR(priv->tx_tfm_michael)) {
+		printk(KERN_DEBUG "lib80211_crypt_tkip: could not allocate "
+		       "crypto API michael_mic\n");
+		priv->tx_tfm_michael = NULL;
+		goto fail;
+	}
+
+	priv->rx_tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0,
+						CRYPTO_ALG_ASYNC);
+	if (IS_ERR(priv->rx_tfm_arc4)) {
+		printk(KERN_DEBUG "lib80211_crypt_tkip: could not allocate "
+		       "crypto API arc4\n");
+		priv->rx_tfm_arc4 = NULL;
+		goto fail;
+	}
+
+	priv->rx_tfm_michael = crypto_alloc_hash("michael_mic", 0,
+						 CRYPTO_ALG_ASYNC);
+	if (IS_ERR(priv->rx_tfm_michael)) {
+		printk(KERN_DEBUG "lib80211_crypt_tkip: could not allocate "
+		       "crypto API michael_mic\n");
+		priv->rx_tfm_michael = NULL;
+		goto fail;
+	}
+
+	return priv;
+
+      fail:
+	if (priv) {
+		if (priv->tx_tfm_michael)
+			crypto_free_hash(priv->tx_tfm_michael);
+		if (priv->tx_tfm_arc4)
+			crypto_free_blkcipher(priv->tx_tfm_arc4);
+		if (priv->rx_tfm_michael)
+			crypto_free_hash(priv->rx_tfm_michael);
+		if (priv->rx_tfm_arc4)
+			crypto_free_blkcipher(priv->rx_tfm_arc4);
+		kfree(priv);
+	}
+
+	return NULL;
+}
+
+static void lib80211_tkip_deinit(void *priv)
+{
+	struct lib80211_tkip_data *_priv = priv;
+	if (_priv) {
+		if (_priv->tx_tfm_michael)
+			crypto_free_hash(_priv->tx_tfm_michael);
+		if (_priv->tx_tfm_arc4)
+			crypto_free_blkcipher(_priv->tx_tfm_arc4);
+		if (_priv->rx_tfm_michael)
+			crypto_free_hash(_priv->rx_tfm_michael);
+		if (_priv->rx_tfm_arc4)
+			crypto_free_blkcipher(_priv->rx_tfm_arc4);
+	}
+	kfree(priv);
+}
+
+static inline u16 RotR1(u16 val)
+{
+	return (val >> 1) | (val << 15);
+}
+
+static inline u8 Lo8(u16 val)
+{
+	return val & 0xff;
+}
+
+static inline u8 Hi8(u16 val)
+{
+	return val >> 8;
+}
+
+static inline u16 Lo16(u32 val)
+{
+	return val & 0xffff;
+}
+
+static inline u16 Hi16(u32 val)
+{
+	return val >> 16;
+}
+
+static inline u16 Mk16(u8 hi, u8 lo)
+{
+	return lo | (((u16) hi) << 8);
+}
+
+static inline u16 Mk16_le(__le16 * v)
+{
+	return le16_to_cpu(*v);
+}
+
+static const u16 Sbox[256] = {
+	0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154,
+	0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A,
+	0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B,
+	0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B,
+	0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F,
+	0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F,
+	0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5,
+	0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F,
+	0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB,
+	0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397,
+	0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED,
+	0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A,
+	0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194,
+	0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3,
+	0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104,
+	0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D,
+	0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39,
+	0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695,
+	0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83,
+	0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76,
+	0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4,
+	0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B,
+	0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0,
+	0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018,
+	0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751,
+	0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85,
+	0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12,
+	0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9,
+	0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7,
+	0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A,
+	0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8,
+	0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A,
+};
+
+static inline u16 _S_(u16 v)
+{
+	u16 t = Sbox[Hi8(v)];
+	return Sbox[Lo8(v)] ^ ((t << 8) | (t >> 8));
+}
+
+#define PHASE1_LOOP_COUNT 8
+
+static void tkip_mixing_phase1(u16 * TTAK, const u8 * TK, const u8 * TA,
+			       u32 IV32)
+{
+	int i, j;
+
+	/* Initialize the 80-bit TTAK from TSC (IV32) and TA[0..5] */
+	TTAK[0] = Lo16(IV32);
+	TTAK[1] = Hi16(IV32);
+	TTAK[2] = Mk16(TA[1], TA[0]);
+	TTAK[3] = Mk16(TA[3], TA[2]);
+	TTAK[4] = Mk16(TA[5], TA[4]);
+
+	for (i = 0; i < PHASE1_LOOP_COUNT; i++) {
+		j = 2 * (i & 1);
+		TTAK[0] += _S_(TTAK[4] ^ Mk16(TK[1 + j], TK[0 + j]));
+		TTAK[1] += _S_(TTAK[0] ^ Mk16(TK[5 + j], TK[4 + j]));
+		TTAK[2] += _S_(TTAK[1] ^ Mk16(TK[9 + j], TK[8 + j]));
+		TTAK[3] += _S_(TTAK[2] ^ Mk16(TK[13 + j], TK[12 + j]));
+		TTAK[4] += _S_(TTAK[3] ^ Mk16(TK[1 + j], TK[0 + j])) + i;
+	}
+}
+
+static void tkip_mixing_phase2(u8 * WEPSeed, const u8 * TK, const u16 * TTAK,
+			       u16 IV16)
+{
+	/* Make temporary area overlap WEP seed so that the final copy can be
+	 * avoided on little endian hosts. */
+	u16 *PPK = (u16 *) & WEPSeed[4];
+
+	/* Step 1 - make copy of TTAK and bring in TSC */
+	PPK[0] = TTAK[0];
+	PPK[1] = TTAK[1];
+	PPK[2] = TTAK[2];
+	PPK[3] = TTAK[3];
+	PPK[4] = TTAK[4];
+	PPK[5] = TTAK[4] + IV16;
+
+	/* Step 2 - 96-bit bijective mixing using S-box */
+	PPK[0] += _S_(PPK[5] ^ Mk16_le((__le16 *) & TK[0]));
+	PPK[1] += _S_(PPK[0] ^ Mk16_le((__le16 *) & TK[2]));
+	PPK[2] += _S_(PPK[1] ^ Mk16_le((__le16 *) & TK[4]));
+	PPK[3] += _S_(PPK[2] ^ Mk16_le((__le16 *) & TK[6]));
+	PPK[4] += _S_(PPK[3] ^ Mk16_le((__le16 *) & TK[8]));
+	PPK[5] += _S_(PPK[4] ^ Mk16_le((__le16 *) & TK[10]));
+
+	PPK[0] += RotR1(PPK[5] ^ Mk16_le((__le16 *) & TK[12]));
+	PPK[1] += RotR1(PPK[0] ^ Mk16_le((__le16 *) & TK[14]));
+	PPK[2] += RotR1(PPK[1]);
+	PPK[3] += RotR1(PPK[2]);
+	PPK[4] += RotR1(PPK[3]);
+	PPK[5] += RotR1(PPK[4]);
+
+	/* Step 3 - bring in last of TK bits, assign 24-bit WEP IV value
+	 * WEPSeed[0..2] is transmitted as WEP IV */
+	WEPSeed[0] = Hi8(IV16);
+	WEPSeed[1] = (Hi8(IV16) | 0x20) & 0x7F;
+	WEPSeed[2] = Lo8(IV16);
+	WEPSeed[3] = Lo8((PPK[5] ^ Mk16_le((__le16 *) & TK[0])) >> 1);
+
+#ifdef __BIG_ENDIAN
+	{
+		int i;
+		for (i = 0; i < 6; i++)
+			PPK[i] = (PPK[i] << 8) | (PPK[i] >> 8);
+	}
+#endif
+}
+
+static int lib80211_tkip_hdr(struct sk_buff *skb, int hdr_len,
+			      u8 * rc4key, int keylen, void *priv)
+{
+	struct lib80211_tkip_data *tkey = priv;
+	int len;
+	u8 *pos;
+	struct ieee80211_hdr *hdr;
+
+	hdr = (struct ieee80211_hdr *)skb->data;
+
+	if (skb_headroom(skb) < 8 || skb->len < hdr_len)
+		return -1;
+
+	if (rc4key == NULL || keylen < 16)
+		return -1;
+
+	if (!tkey->tx_phase1_done) {
+		tkip_mixing_phase1(tkey->tx_ttak, tkey->key, hdr->addr2,
+				   tkey->tx_iv32);
+		tkey->tx_phase1_done = 1;
+	}
+	tkip_mixing_phase2(rc4key, tkey->key, tkey->tx_ttak, tkey->tx_iv16);
+
+	len = skb->len - hdr_len;
+	pos = skb_push(skb, 8);
+	memmove(pos, pos + 8, hdr_len);
+	pos += hdr_len;
+
+	*pos++ = *rc4key;
+	*pos++ = *(rc4key + 1);
+	*pos++ = *(rc4key + 2);
+	*pos++ = (tkey->key_idx << 6) | (1 << 5) /* Ext IV included */ ;
+	*pos++ = tkey->tx_iv32 & 0xff;
+	*pos++ = (tkey->tx_iv32 >> 8) & 0xff;
+	*pos++ = (tkey->tx_iv32 >> 16) & 0xff;
+	*pos++ = (tkey->tx_iv32 >> 24) & 0xff;
+
+	tkey->tx_iv16++;
+	if (tkey->tx_iv16 == 0) {
+		tkey->tx_phase1_done = 0;
+		tkey->tx_iv32++;
+	}
+
+	return 8;
+}
+
+static int lib80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
+{
+	struct lib80211_tkip_data *tkey = priv;
+	struct blkcipher_desc desc = { .tfm = tkey->tx_tfm_arc4 };
+	int len;
+	u8 rc4key[16], *pos, *icv;
+	u32 crc;
+	struct scatterlist sg;
+
+	if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) {
+		if (net_ratelimit()) {
+			struct ieee80211_hdr *hdr =
+			    (struct ieee80211_hdr *)skb->data;
+			printk(KERN_DEBUG ": TKIP countermeasures: dropped "
+			       "TX packet to %pM\n", hdr->addr1);
+		}
+		return -1;
+	}
+
+	if (skb_tailroom(skb) < 4 || skb->len < hdr_len)
+		return -1;
+
+	len = skb->len - hdr_len;
+	pos = skb->data + hdr_len;
+
+	if ((lib80211_tkip_hdr(skb, hdr_len, rc4key, 16, priv)) < 0)
+		return -1;
+
+	icv = skb_put(skb, 4);
+
+	crc = ~crc32_le(~0, pos, len);
+	icv[0] = crc;
+	icv[1] = crc >> 8;
+	icv[2] = crc >> 16;
+	icv[3] = crc >> 24;
+
+	crypto_blkcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16);
+	sg_init_one(&sg, pos, len + 4);
+	return crypto_blkcipher_encrypt(&desc, &sg, &sg, len + 4);
+}
+
+/*
+ * deal with seq counter wrapping correctly.
+ * refer to timer_after() for jiffies wrapping handling
+ */
+static inline int tkip_replay_check(u32 iv32_n, u16 iv16_n,
+				    u32 iv32_o, u16 iv16_o)
+{
+	if ((s32)iv32_n - (s32)iv32_o < 0 ||
+	    (iv32_n == iv32_o && iv16_n <= iv16_o))
+		return 1;
+	return 0;
+}
+
+static int lib80211_tkip_decrypt(struct sk_buff *skb, int hdr_len, void *priv)
+{
+	struct lib80211_tkip_data *tkey = priv;
+	struct blkcipher_desc desc = { .tfm = tkey->rx_tfm_arc4 };
+	u8 rc4key[16];
+	u8 keyidx, *pos;
+	u32 iv32;
+	u16 iv16;
+	struct ieee80211_hdr *hdr;
+	u8 icv[4];
+	u32 crc;
+	struct scatterlist sg;
+	int plen;
+
+	hdr = (struct ieee80211_hdr *)skb->data;
+
+	if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) {
+		if (net_ratelimit()) {
+			printk(KERN_DEBUG ": TKIP countermeasures: dropped "
+			       "received packet from %pM\n", hdr->addr2);
+		}
+		return -1;
+	}
+
+	if (skb->len < hdr_len + 8 + 4)
+		return -1;
+
+	pos = skb->data + hdr_len;
+	keyidx = pos[3];
+	if (!(keyidx & (1 << 5))) {
+		if (net_ratelimit()) {
+			printk(KERN_DEBUG "TKIP: received packet without ExtIV"
+			       " flag from %pM\n", hdr->addr2);
+		}
+		return -2;
+	}
+	keyidx >>= 6;
+	if (tkey->key_idx != keyidx) {
+		printk(KERN_DEBUG "TKIP: RX tkey->key_idx=%d frame "
+		       "keyidx=%d priv=%p\n", tkey->key_idx, keyidx, priv);
+		return -6;
+	}
+	if (!tkey->key_set) {
+		if (net_ratelimit()) {
+			printk(KERN_DEBUG "TKIP: received packet from %pM"
+			       " with keyid=%d that does not have a configured"
+			       " key\n", hdr->addr2, keyidx);
+		}
+		return -3;
+	}
+	iv16 = (pos[0] << 8) | pos[2];
+	iv32 = pos[4] | (pos[5] << 8) | (pos[6] << 16) | (pos[7] << 24);
+	pos += 8;
+
+	if (tkip_replay_check(iv32, iv16, tkey->rx_iv32, tkey->rx_iv16)) {
+		if (net_ratelimit()) {
+			printk(KERN_DEBUG "TKIP: replay detected: STA=%pM"
+			       " previous TSC %08x%04x received TSC "
+			       "%08x%04x\n", hdr->addr2,
+			       tkey->rx_iv32, tkey->rx_iv16, iv32, iv16);
+		}
+		tkey->dot11RSNAStatsTKIPReplays++;
+		return -4;
+	}
+
+	if (iv32 != tkey->rx_iv32 || !tkey->rx_phase1_done) {
+		tkip_mixing_phase1(tkey->rx_ttak, tkey->key, hdr->addr2, iv32);
+		tkey->rx_phase1_done = 1;
+	}
+	tkip_mixing_phase2(rc4key, tkey->key, tkey->rx_ttak, iv16);
+
+	plen = skb->len - hdr_len - 12;
+
+	crypto_blkcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16);
+	sg_init_one(&sg, pos, plen + 4);
+	if (crypto_blkcipher_decrypt(&desc, &sg, &sg, plen + 4)) {
+		if (net_ratelimit()) {
+			printk(KERN_DEBUG ": TKIP: failed to decrypt "
+			       "received packet from %pM\n",
+			       hdr->addr2);
+		}
+		return -7;
+	}
+
+	crc = ~crc32_le(~0, pos, plen);
+	icv[0] = crc;
+	icv[1] = crc >> 8;
+	icv[2] = crc >> 16;
+	icv[3] = crc >> 24;
+	if (memcmp(icv, pos + plen, 4) != 0) {
+		if (iv32 != tkey->rx_iv32) {
+			/* Previously cached Phase1 result was already lost, so
+			 * it needs to be recalculated for the next packet. */
+			tkey->rx_phase1_done = 0;
+		}
+		if (net_ratelimit()) {
+			printk(KERN_DEBUG "TKIP: ICV error detected: STA="
+			       "%pM\n", hdr->addr2);
+		}
+		tkey->dot11RSNAStatsTKIPICVErrors++;
+		return -5;
+	}
+
+	/* Update real counters only after Michael MIC verification has
+	 * completed */
+	tkey->rx_iv32_new = iv32;
+	tkey->rx_iv16_new = iv16;
+
+	/* Remove IV and ICV */
+	memmove(skb->data + 8, skb->data, hdr_len);
+	skb_pull(skb, 8);
+	skb_trim(skb, skb->len - 4);
+
+	return keyidx;
+}
+
+static int michael_mic(struct crypto_hash *tfm_michael, u8 * key, u8 * hdr,
+		       u8 * data, size_t data_len, u8 * mic)
+{
+	struct hash_desc desc;
+	struct scatterlist sg[2];
+
+	if (tfm_michael == NULL) {
+		printk(KERN_WARNING "michael_mic: tfm_michael == NULL\n");
+		return -1;
+	}
+	sg_init_table(sg, 2);
+	sg_set_buf(&sg[0], hdr, 16);
+	sg_set_buf(&sg[1], data, data_len);
+
+	if (crypto_hash_setkey(tfm_michael, key, 8))
+		return -1;
+
+	desc.tfm = tfm_michael;
+	desc.flags = 0;
+	return crypto_hash_digest(&desc, sg, data_len + 16, mic);
+}
+
+static void michael_mic_hdr(struct sk_buff *skb, u8 * hdr)
+{
+	struct ieee80211_hdr *hdr11;
+
+	hdr11 = (struct ieee80211_hdr *)skb->data;
+
+	switch (le16_to_cpu(hdr11->frame_control) &
+		(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {
+	case IEEE80211_FCTL_TODS:
+		memcpy(hdr, hdr11->addr3, ETH_ALEN);	/* DA */
+		memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN);	/* SA */
+		break;
+	case IEEE80211_FCTL_FROMDS:
+		memcpy(hdr, hdr11->addr1, ETH_ALEN);	/* DA */
+		memcpy(hdr + ETH_ALEN, hdr11->addr3, ETH_ALEN);	/* SA */
+		break;
+	case IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS:
+		memcpy(hdr, hdr11->addr3, ETH_ALEN);	/* DA */
+		memcpy(hdr + ETH_ALEN, hdr11->addr4, ETH_ALEN);	/* SA */
+		break;
+	case 0:
+		memcpy(hdr, hdr11->addr1, ETH_ALEN);	/* DA */
+		memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN);	/* SA */
+		break;
+	}
+
+	if (ieee80211_is_data_qos(hdr11->frame_control)) {
+		hdr[12] = le16_to_cpu(*ieee80211_get_qos_ctl(hdr11))
+			& IEEE80211_QOS_CTL_TID_MASK;
+	} else
+		hdr[12] = 0;		/* priority */
+
+	hdr[13] = hdr[14] = hdr[15] = 0;	/* reserved */
+}
+
+static int lib80211_michael_mic_add(struct sk_buff *skb, int hdr_len,
+				     void *priv)
+{
+	struct lib80211_tkip_data *tkey = priv;
+	u8 *pos;
+
+	if (skb_tailroom(skb) < 8 || skb->len < hdr_len) {
+		printk(KERN_DEBUG "Invalid packet for Michael MIC add "
+		       "(tailroom=%d hdr_len=%d skb->len=%d)\n",
+		       skb_tailroom(skb), hdr_len, skb->len);
+		return -1;
+	}
+
+	michael_mic_hdr(skb, tkey->tx_hdr);
+	pos = skb_put(skb, 8);
+	if (michael_mic(tkey->tx_tfm_michael, &tkey->key[16], tkey->tx_hdr,
+			skb->data + hdr_len, skb->len - 8 - hdr_len, pos))
+		return -1;
+
+	return 0;
+}
+
+static void lib80211_michael_mic_failure(struct net_device *dev,
+					  struct ieee80211_hdr *hdr,
+					  int keyidx)
+{
+	union iwreq_data wrqu;
+	struct iw_michaelmicfailure ev;
+
+	/* TODO: needed parameters: count, keyid, key type, TSC */
+	memset(&ev, 0, sizeof(ev));
+	ev.flags = keyidx & IW_MICFAILURE_KEY_ID;
+	if (hdr->addr1[0] & 0x01)
+		ev.flags |= IW_MICFAILURE_GROUP;
+	else
+		ev.flags |= IW_MICFAILURE_PAIRWISE;
+	ev.src_addr.sa_family = ARPHRD_ETHER;
+	memcpy(ev.src_addr.sa_data, hdr->addr2, ETH_ALEN);
+	memset(&wrqu, 0, sizeof(wrqu));
+	wrqu.data.length = sizeof(ev);
+	wireless_send_event(dev, IWEVMICHAELMICFAILURE, &wrqu, (char *)&ev);
+}
+
+static int lib80211_michael_mic_verify(struct sk_buff *skb, int keyidx,
+					int hdr_len, void *priv)
+{
+	struct lib80211_tkip_data *tkey = priv;
+	u8 mic[8];
+
+	if (!tkey->key_set)
+		return -1;
+
+	michael_mic_hdr(skb, tkey->rx_hdr);
+	if (michael_mic(tkey->rx_tfm_michael, &tkey->key[24], tkey->rx_hdr,
+			skb->data + hdr_len, skb->len - 8 - hdr_len, mic))
+		return -1;
+	if (memcmp(mic, skb->data + skb->len - 8, 8) != 0) {
+		struct ieee80211_hdr *hdr;
+		hdr = (struct ieee80211_hdr *)skb->data;
+		printk(KERN_DEBUG "%s: Michael MIC verification failed for "
+		       "MSDU from %pM keyidx=%d\n",
+		       skb->dev ? skb->dev->name : "N/A", hdr->addr2,
+		       keyidx);
+		if (skb->dev)
+			lib80211_michael_mic_failure(skb->dev, hdr, keyidx);
+		tkey->dot11RSNAStatsTKIPLocalMICFailures++;
+		return -1;
+	}
+
+	/* Update TSC counters for RX now that the packet verification has
+	 * completed. */
+	tkey->rx_iv32 = tkey->rx_iv32_new;
+	tkey->rx_iv16 = tkey->rx_iv16_new;
+
+	skb_trim(skb, skb->len - 8);
+
+	return 0;
+}
+
+static int lib80211_tkip_set_key(void *key, int len, u8 * seq, void *priv)
+{
+	struct lib80211_tkip_data *tkey = priv;
+	int keyidx;
+	struct crypto_hash *tfm = tkey->tx_tfm_michael;
+	struct crypto_blkcipher *tfm2 = tkey->tx_tfm_arc4;
+	struct crypto_hash *tfm3 = tkey->rx_tfm_michael;
+	struct crypto_blkcipher *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);
+		tkey->key_set = 1;
+		tkey->tx_iv16 = 1;	/* TSC is initialized to 1 */
+		if (seq) {
+			tkey->rx_iv32 = (seq[5] << 24) | (seq[4] << 16) |
+			    (seq[3] << 8) | seq[2];
+			tkey->rx_iv16 = (seq[1] << 8) | seq[0];
+		}
+	} else if (len == 0)
+		tkey->key_set = 0;
+	else
+		return -1;
+
+	return 0;
+}
+
+static int lib80211_tkip_get_key(void *key, int len, u8 * seq, void *priv)
+{
+	struct lib80211_tkip_data *tkey = priv;
+
+	if (len < TKIP_KEY_LEN)
+		return -1;
+
+	if (!tkey->key_set)
+		return 0;
+	memcpy(key, tkey->key, TKIP_KEY_LEN);
+
+	if (seq) {
+		/* Return the sequence number of the last transmitted frame. */
+		u16 iv16 = tkey->tx_iv16;
+		u32 iv32 = tkey->tx_iv32;
+		if (iv16 == 0)
+			iv32--;
+		iv16--;
+		seq[0] = tkey->tx_iv16;
+		seq[1] = tkey->tx_iv16 >> 8;
+		seq[2] = tkey->tx_iv32;
+		seq[3] = tkey->tx_iv32 >> 8;
+		seq[4] = tkey->tx_iv32 >> 16;
+		seq[5] = tkey->tx_iv32 >> 24;
+	}
+
+	return TKIP_KEY_LEN;
+}
+
+static char *lib80211_tkip_print_stats(char *p, void *priv)
+{
+	struct lib80211_tkip_data *tkip = priv;
+	p += sprintf(p, "key[%d] alg=TKIP key_set=%d "
+		     "tx_pn=%02x%02x%02x%02x%02x%02x "
+		     "rx_pn=%02x%02x%02x%02x%02x%02x "
+		     "replays=%d icv_errors=%d local_mic_failures=%d\n",
+		     tkip->key_idx, tkip->key_set,
+		     (tkip->tx_iv32 >> 24) & 0xff,
+		     (tkip->tx_iv32 >> 16) & 0xff,
+		     (tkip->tx_iv32 >> 8) & 0xff,
+		     tkip->tx_iv32 & 0xff,
+		     (tkip->tx_iv16 >> 8) & 0xff,
+		     tkip->tx_iv16 & 0xff,
+		     (tkip->rx_iv32 >> 24) & 0xff,
+		     (tkip->rx_iv32 >> 16) & 0xff,
+		     (tkip->rx_iv32 >> 8) & 0xff,
+		     tkip->rx_iv32 & 0xff,
+		     (tkip->rx_iv16 >> 8) & 0xff,
+		     tkip->rx_iv16 & 0xff,
+		     tkip->dot11RSNAStatsTKIPReplays,
+		     tkip->dot11RSNAStatsTKIPICVErrors,
+		     tkip->dot11RSNAStatsTKIPLocalMICFailures);
+	return p;
+}
+
+static struct lib80211_crypto_ops lib80211_crypt_tkip = {
+	.name = "TKIP",
+	.init = lib80211_tkip_init,
+	.deinit = lib80211_tkip_deinit,
+	.build_iv = lib80211_tkip_hdr,
+	.encrypt_mpdu = lib80211_tkip_encrypt,
+	.decrypt_mpdu = lib80211_tkip_decrypt,
+	.encrypt_msdu = lib80211_michael_mic_add,
+	.decrypt_msdu = lib80211_michael_mic_verify,
+	.set_key = lib80211_tkip_set_key,
+	.get_key = lib80211_tkip_get_key,
+	.print_stats = lib80211_tkip_print_stats,
+	.extra_mpdu_prefix_len = 4 + 4,	/* IV + ExtIV */
+	.extra_mpdu_postfix_len = 4,	/* ICV */
+	.extra_msdu_postfix_len = 8,	/* MIC */
+	.get_flags = lib80211_tkip_get_flags,
+	.set_flags = lib80211_tkip_set_flags,
+	.owner = THIS_MODULE,
+};
+
+static int __init lib80211_crypto_tkip_init(void)
+{
+	return lib80211_register_crypto_ops(&lib80211_crypt_tkip);
+}
+
+static void __exit lib80211_crypto_tkip_exit(void)
+{
+	lib80211_unregister_crypto_ops(&lib80211_crypt_tkip);
+}
+
+module_init(lib80211_crypto_tkip_init);
+module_exit(lib80211_crypto_tkip_exit);