| /* |
| * 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 <linux/crypto.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_cipher *rx_tfm_arc4; |
| struct crypto_shash *rx_tfm_michael; |
| struct crypto_cipher *tx_tfm_arc4; |
| struct crypto_shash *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_cipher("arc4", 0, 0); |
| if (IS_ERR(priv->tx_tfm_arc4)) { |
| 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)) { |
| priv->tx_tfm_michael = NULL; |
| goto fail; |
| } |
| |
| priv->rx_tfm_arc4 = crypto_alloc_cipher("arc4", 0, 0); |
| if (IS_ERR(priv->rx_tfm_arc4)) { |
| 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)) { |
| priv->rx_tfm_michael = NULL; |
| goto fail; |
| } |
| |
| return priv; |
| |
| fail: |
| if (priv) { |
| crypto_free_shash(priv->tx_tfm_michael); |
| crypto_free_cipher(priv->tx_tfm_arc4); |
| crypto_free_shash(priv->rx_tfm_michael); |
| crypto_free_cipher(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_shash(_priv->tx_tfm_michael); |
| crypto_free_cipher(_priv->tx_tfm_arc4); |
| crypto_free_shash(_priv->rx_tfm_michael); |
| crypto_free_cipher(_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; |
| int len; |
| u8 rc4key[16], *pos, *icv; |
| u32 crc; |
| int i; |
| |
| 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_cipher_setkey(tkey->tx_tfm_arc4, rc4key, 16); |
| for (i = 0; i < len + 4; i++) |
| crypto_cipher_encrypt_one(tkey->tx_tfm_arc4, pos + i, pos + i); |
| return 0; |
| } |
| |
| /* |
| * 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; |
| u8 rc4key[16]; |
| u8 keyidx, *pos; |
| u32 iv32; |
| u16 iv16; |
| struct ieee80211_hdr *hdr; |
| u8 icv[4]; |
| u32 crc; |
| int plen; |
| int i; |
| |
| 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_cipher_setkey(tkey->rx_tfm_arc4, rc4key, 16); |
| for (i = 0; i < plen + 4; i++) |
| crypto_cipher_decrypt_one(tkey->rx_tfm_arc4, pos + i, pos + i); |
| |
| 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_shash *tfm_michael, u8 *key, u8 *hdr, |
| u8 *data, size_t data_len, u8 *mic) |
| { |
| SHASH_DESC_ON_STACK(desc, tfm_michael); |
| int err; |
| |
| if (tfm_michael == NULL) { |
| pr_warn("%s(): tfm_michael == NULL\n", __func__); |
| return -1; |
| } |
| |
| desc->tfm = tfm_michael; |
| |
| if (crypto_shash_setkey(tfm_michael, key, 8)) |
| return -1; |
| |
| err = crypto_shash_init(desc); |
| if (err) |
| goto out; |
| err = crypto_shash_update(desc, hdr, 16); |
| if (err) |
| goto out; |
| err = crypto_shash_update(desc, data, data_len); |
| if (err) |
| goto out; |
| err = crypto_shash_final(desc, mic); |
| |
| out: |
| shash_desc_zero(desc); |
| 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_shash *tfm = tkey->tx_tfm_michael; |
| struct crypto_cipher *tfm2 = tkey->tx_tfm_arc4; |
| struct crypto_shash *tfm3 = tkey->rx_tfm_michael; |
| struct crypto_cipher *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); |