summaryrefslogtreecommitdiff
path: root/net/wireless/lib80211_crypt_tkip.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/wireless/lib80211_crypt_tkip.c')
-rw-r--r--net/wireless/lib80211_crypt_tkip.c784
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);
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-14 19:03:19 +0300