cregit-Linux how code gets into the kernel

Release 4.8 net/wireless/lib80211_crypt_tkip.c

Directory: net/wireless
/*
 * 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; }

Contributors

PersonTokensPropCommitsCommitProp
james ketrenosjames ketrenos3487.18%133.33%
jeff garzikjeff garzik37.69%133.33%
john w. linvillejohn w. linville25.13%133.33%
Total39100.00%3100.00%


static unsigned long lib80211_tkip_get_flags(void *priv) { struct lib80211_tkip_data *_priv = priv; return _priv->flags; }

Contributors

PersonTokensPropCommitsCommitProp
james ketrenosjames ketrenos2086.96%250.00%
john w. linvillejohn w. linville28.70%125.00%
jeff garzikjeff garzik14.35%125.00%
Total23100.00%4100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik12757.21%330.00%
yi zhuyi zhu6027.03%220.00%
herbert xuherbert xu2913.06%330.00%
james ketrenosjames ketrenos41.80%110.00%
john w. linvillejohn w. linville20.90%110.00%
Total222100.00%10100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik3358.93%125.00%
yi zhuyi zhu1730.36%125.00%
herbert xuherbert xu47.14%125.00%
john w. linvillejohn w. linville23.57%125.00%
Total56100.00%4100.00%


static inline u16 RotR1(u16 val) { return (val >> 1) | (val << 15); }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik23100.00%1100.00%
Total23100.00%1100.00%


static inline u8 Lo8(u16 val) { return val & 0xff; }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik15100.00%1100.00%
Total15100.00%1100.00%


static inline u8 Hi8(u16 val) { return val >> 8; }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik15100.00%1100.00%
Total15100.00%1100.00%


static inline u16 Lo16(u32 val) { return val & 0xffff; }

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PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik15100.00%1100.00%
Total15100.00%1100.00%


static inline u16 Hi16(u32 val) { return val >> 16; }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik15100.00%1100.00%
Total15100.00%1100.00%


static inline u16 Mk16(u8 hi, u8 lo) { return lo | (((u16) hi) << 8); }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik27100.00%1100.00%
Total27100.00%1100.00%


static inline u16 Mk16_le(__le16 * v) { return le16_to_cpu(*v); }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik1794.44%150.00%
al viroal viro15.56%150.00%
Total18100.00%2100.00%

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)); }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik44100.00%1100.00%
Total44100.00%1100.00%

#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; } }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik280100.00%1100.00%
Total280100.00%1100.00%


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 }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik46698.11%150.00%
al viroal viro91.89%150.00%
Total475100.00%2100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik21173.01%116.67%
yi zhuyi zhu4415.22%116.67%
james ketrenosjames ketrenos269.00%233.33%
andriy tkachukandriy tkachuk41.38%116.67%
john w. linvillejohn w. linville41.38%116.67%
Total289100.00%6100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
james ketrenosjames ketrenos11339.65%214.29%
yi zhuyi zhu7024.56%321.43%
herbert xuherbert xu5117.89%214.29%
jeff garzikjeff garzik2910.18%214.29%
andriy tkachukandriy tkachuk93.16%17.14%
john w. linvillejohn w. linville51.75%17.14%
jens axboejens axboe51.75%17.14%
joe perchesjoe perches31.05%214.29%
Total285100.00%14100.00%

/* * 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; }

Contributors

PersonTokensPropCommitsCommitProp
jeff garzikjeff garzik49100.00%1100.00%
Total49100.00%1100.00%


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(