linux/net/wireless/lib80211_crypt_tkip.c
Arnd Bergmann 10f3366b4d wireless: fix bogus maybe-uninitialized warning
The hostap_80211_rx() function is supposed to set up the mac addresses
for four possible cases, based on two bits of input data. For
some reason, gcc decides that it's possible that none of the these
four cases apply and the addresses remain uninitialized:

drivers/net/wireless/intersil/hostap/hostap_80211_rx.c: In function ‘hostap_80211_rx’:
arch/x86/include/asm/string_32.h:77:14: warning: ‘src’ may be used uninitialized in this function [-Wmaybe-uninitialized]
drivers/net/wireless/intel/ipw2x00/libipw_rx.c: In function ‘libipw_rx’:
arch/x86/include/asm/string_32.h:77:14: error: ‘dst’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
arch/x86/include/asm/string_32.h:78:22: error: ‘*((void *)&dst+4)’ may be used uninitialized in this function [-Werror=maybe-uninitialized]

This warning is clearly nonsense, but changing the last case into
'default' makes it obvious to the compiler too, which avoids the
warning and probably leads to better object code too.

The same code is duplicated several times in the kernel, so this
patch uses the same workaround for all copies. The exact configuration
was hit only very rarely in randconfig builds and I only saw it
in three drivers, but I assume that all of them are potentially
affected, and it's better to keep the code consistent.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2016-11-17 08:46:38 +02:00

772 lines
21 KiB
C

/*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#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 <crypto/hash.h>
#include <crypto/skcipher.h>
#include <linux/crc32.h>
#include <net/lib80211.h>
MODULE_AUTHOR("Jouni Malinen");
MODULE_DESCRIPTION("lib80211 crypt: TKIP");
MODULE_LICENSE("GPL");
#define TKIP_HDR_LEN 8
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_skcipher *rx_tfm_arc4;
struct crypto_ahash *rx_tfm_michael;
struct crypto_skcipher *tx_tfm_arc4;
struct crypto_ahash *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_skcipher("ecb(arc4)", 0,
CRYPTO_ALG_ASYNC);
if (IS_ERR(priv->tx_tfm_arc4)) {
priv->tx_tfm_arc4 = NULL;
goto fail;
}
priv->tx_tfm_michael = crypto_alloc_ahash("michael_mic", 0,
CRYPTO_ALG_ASYNC);
if (IS_ERR(priv->tx_tfm_michael)) {
priv->tx_tfm_michael = NULL;
goto fail;
}
priv->rx_tfm_arc4 = crypto_alloc_skcipher("ecb(arc4)", 0,
CRYPTO_ALG_ASYNC);
if (IS_ERR(priv->rx_tfm_arc4)) {
priv->rx_tfm_arc4 = NULL;
goto fail;
}
priv->rx_tfm_michael = crypto_alloc_ahash("michael_mic", 0,
CRYPTO_ALG_ASYNC);
if (IS_ERR(priv->rx_tfm_michael)) {
priv->rx_tfm_michael = NULL;
goto fail;
}
return priv;
fail:
if (priv) {
crypto_free_ahash(priv->tx_tfm_michael);
crypto_free_skcipher(priv->tx_tfm_arc4);
crypto_free_ahash(priv->rx_tfm_michael);
crypto_free_skcipher(priv->rx_tfm_arc4);
kfree(priv);
}
return NULL;
}
static void lib80211_tkip_deinit(void *priv)
{
struct lib80211_tkip_data *_priv = priv;
if (_priv) {
crypto_free_ahash(_priv->tx_tfm_michael);
crypto_free_skcipher(_priv->tx_tfm_arc4);
crypto_free_ahash(_priv->rx_tfm_michael);
crypto_free_skcipher(_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;
u8 *pos;
struct ieee80211_hdr *hdr;
hdr = (struct ieee80211_hdr *)skb->data;
if (skb_headroom(skb) < TKIP_HDR_LEN || 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);
pos = skb_push(skb, TKIP_HDR_LEN);
memmove(pos, pos + TKIP_HDR_LEN, 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 TKIP_HDR_LEN;
}
static int lib80211_tkip_encrypt(struct sk_buff *skb, int hdr_len, void *priv)
{
struct lib80211_tkip_data *tkey = priv;
SKCIPHER_REQUEST_ON_STACK(req, tkey->tx_tfm_arc4);
int len;
u8 rc4key[16], *pos, *icv;
u32 crc;
struct scatterlist sg;
int err;
if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) {
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
net_dbg_ratelimited("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;
crc = ~crc32_le(~0, pos, len);
icv = skb_put(skb, 4);
icv[0] = crc;
icv[1] = crc >> 8;
icv[2] = crc >> 16;
icv[3] = crc >> 24;
crypto_skcipher_setkey(tkey->tx_tfm_arc4, rc4key, 16);
sg_init_one(&sg, pos, len + 4);
skcipher_request_set_tfm(req, tkey->tx_tfm_arc4);
skcipher_request_set_callback(req, 0, NULL, NULL);
skcipher_request_set_crypt(req, &sg, &sg, len + 4, NULL);
err = crypto_skcipher_encrypt(req);
skcipher_request_zero(req);
return err;
}
/*
* 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;
SKCIPHER_REQUEST_ON_STACK(req, 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;
int err;
hdr = (struct ieee80211_hdr *)skb->data;
if (tkey->flags & IEEE80211_CRYPTO_TKIP_COUNTERMEASURES) {
net_dbg_ratelimited("TKIP countermeasures: dropped received packet from %pM\n",
hdr->addr2);
return -1;
}
if (skb->len < hdr_len + TKIP_HDR_LEN + 4)
return -1;
pos = skb->data + hdr_len;
keyidx = pos[3];
if (!(keyidx & (1 << 5))) {
net_dbg_ratelimited("TKIP: received packet without ExtIV flag from %pM\n",
hdr->addr2);
return -2;
}
keyidx >>= 6;
if (tkey->key_idx != keyidx) {
net_dbg_ratelimited("TKIP: RX tkey->key_idx=%d frame keyidx=%d\n",
tkey->key_idx, keyidx);
return -6;
}
if (!tkey->key_set) {
net_dbg_ratelimited("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 += TKIP_HDR_LEN;
if (tkip_replay_check(iv32, iv16, tkey->rx_iv32, tkey->rx_iv16)) {
#ifdef CONFIG_LIB80211_DEBUG
net_dbg_ratelimited("TKIP: replay detected: STA=%pM previous TSC %08x%04x received TSC %08x%04x\n",
hdr->addr2, tkey->rx_iv32, tkey->rx_iv16,
iv32, iv16);
#endif
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_skcipher_setkey(tkey->rx_tfm_arc4, rc4key, 16);
sg_init_one(&sg, pos, plen + 4);
skcipher_request_set_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) {
net_dbg_ratelimited("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;
}
#ifdef CONFIG_LIB80211_DEBUG
net_dbg_ratelimited("TKIP: ICV error detected: STA=%pM\n",
hdr->addr2);
#endif
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 + TKIP_HDR_LEN, skb->data, hdr_len);
skb_pull(skb, TKIP_HDR_LEN);
skb_trim(skb, skb->len - 4);
return keyidx;
}
static int michael_mic(struct crypto_ahash *tfm_michael, u8 * key, u8 * hdr,
u8 * data, size_t data_len, u8 * mic)
{
AHASH_REQUEST_ON_STACK(req, tfm_michael);
struct scatterlist sg[2];
int err;
if (tfm_michael == NULL) {
pr_warn("%s(): tfm_michael == NULL\n", __func__);
return -1;
}
sg_init_table(sg, 2);
sg_set_buf(&sg[0], hdr, 16);
sg_set_buf(&sg[1], data, data_len);
if (crypto_ahash_setkey(tfm_michael, key, 8))
return -1;
ahash_request_set_tfm(req, tfm_michael);
ahash_request_set_callback(req, 0, NULL, NULL);
ahash_request_set_crypt(req, sg, mic, data_len + 16);
err = crypto_ahash_digest(req);
ahash_request_zero(req);
return err;
}
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;
default:
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(*((__le16 *)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_ahash *tfm = tkey->tx_tfm_michael;
struct crypto_skcipher *tfm2 = tkey->tx_tfm_arc4;
struct crypto_ahash *tfm3 = tkey->rx_tfm_michael;
struct crypto_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);
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 void lib80211_tkip_print_stats(struct seq_file *m, void *priv)
{
struct lib80211_tkip_data *tkip = priv;
seq_printf(m,
"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);
}
static struct lib80211_crypto_ops lib80211_crypt_tkip = {
.name = "TKIP",
.init = lib80211_tkip_init,
.deinit = lib80211_tkip_deinit,
.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);