Commit | Line | Data |
---|---|---|
f0706e82 JB |
1 | /* |
2 | * Copyright 2002-2004, Instant802 Networks, Inc. | |
3 | * Copyright 2005, Devicescape Software, Inc. | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 as | |
7 | * published by the Free Software Foundation. | |
8 | */ | |
f0706e82 | 9 | #include <linux/kernel.h> |
8c046c8c | 10 | #include <linux/bitops.h> |
f0706e82 JB |
11 | #include <linux/types.h> |
12 | #include <linux/netdevice.h> | |
8c046c8c | 13 | #include <asm/unaligned.h> |
f0706e82 JB |
14 | |
15 | #include <net/mac80211.h> | |
2c8dccc7 | 16 | #include "key.h" |
f0706e82 JB |
17 | #include "tkip.h" |
18 | #include "wep.h" | |
19 | ||
f0706e82 JB |
20 | #define PHASE1_LOOP_COUNT 8 |
21 | ||
8c046c8c HH |
22 | /* |
23 | * 2-byte by 2-byte subset of the full AES S-box table; second part of this | |
24 | * table is identical to first part but byte-swapped | |
25 | */ | |
f0706e82 JB |
26 | static const u16 tkip_sbox[256] = |
27 | { | |
28 | 0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154, | |
29 | 0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A, | |
30 | 0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B, | |
31 | 0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B, | |
32 | 0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F, | |
33 | 0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F, | |
34 | 0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5, | |
35 | 0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F, | |
36 | 0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB, | |
37 | 0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397, | |
38 | 0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED, | |
39 | 0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A, | |
40 | 0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194, | |
41 | 0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3, | |
42 | 0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104, | |
43 | 0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D, | |
44 | 0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39, | |
45 | 0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695, | |
46 | 0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83, | |
47 | 0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76, | |
48 | 0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4, | |
49 | 0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B, | |
50 | 0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0, | |
51 | 0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018, | |
52 | 0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751, | |
53 | 0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85, | |
54 | 0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12, | |
55 | 0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9, | |
56 | 0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7, | |
57 | 0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A, | |
58 | 0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8, | |
59 | 0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A, | |
60 | }; | |
61 | ||
8c046c8c | 62 | static u16 tkipS(u16 val) |
f0706e82 | 63 | { |
8c046c8c | 64 | return tkip_sbox[val & 0xff] ^ swab16(tkip_sbox[val >> 8]); |
f0706e82 JB |
65 | } |
66 | ||
c801242c HH |
67 | static u8 *write_tkip_iv(u8 *pos, u16 iv16) |
68 | { | |
69 | *pos++ = iv16 >> 8; | |
70 | *pos++ = ((iv16 >> 8) | 0x20) & 0x7f; | |
71 | *pos++ = iv16 & 0xFF; | |
72 | return pos; | |
73 | } | |
74 | ||
8c046c8c HH |
75 | /* |
76 | * P1K := Phase1(TA, TK, TSC) | |
f0706e82 JB |
77 | * TA = transmitter address (48 bits) |
78 | * TK = dot11DefaultKeyValue or dot11KeyMappingValue (128 bits) | |
79 | * TSC = TKIP sequence counter (48 bits, only 32 msb bits used) | |
80 | * P1K: 80 bits | |
81 | */ | |
7c70537f HH |
82 | static void tkip_mixing_phase1(const u8 *tk, struct tkip_ctx *ctx, |
83 | const u8 *ta, u32 tsc_IV32) | |
f0706e82 JB |
84 | { |
85 | int i, j; | |
82a57447 | 86 | u16 *p1k = ctx->p1k; |
f0706e82 | 87 | |
8c046c8c HH |
88 | p1k[0] = tsc_IV32 & 0xFFFF; |
89 | p1k[1] = tsc_IV32 >> 16; | |
90 | p1k[2] = get_unaligned_le16(ta + 0); | |
91 | p1k[3] = get_unaligned_le16(ta + 2); | |
92 | p1k[4] = get_unaligned_le16(ta + 4); | |
f0706e82 JB |
93 | |
94 | for (i = 0; i < PHASE1_LOOP_COUNT; i++) { | |
95 | j = 2 * (i & 1); | |
8c046c8c HH |
96 | p1k[0] += tkipS(p1k[4] ^ get_unaligned_le16(tk + 0 + j)); |
97 | p1k[1] += tkipS(p1k[0] ^ get_unaligned_le16(tk + 4 + j)); | |
98 | p1k[2] += tkipS(p1k[1] ^ get_unaligned_le16(tk + 8 + j)); | |
99 | p1k[3] += tkipS(p1k[2] ^ get_unaligned_le16(tk + 12 + j)); | |
100 | p1k[4] += tkipS(p1k[3] ^ get_unaligned_le16(tk + 0 + j)) + i; | |
f0706e82 | 101 | } |
82a57447 | 102 | ctx->initialized = 1; |
f0706e82 JB |
103 | } |
104 | ||
7c70537f | 105 | static void tkip_mixing_phase2(const u8 *tk, struct tkip_ctx *ctx, |
3c838099 | 106 | u16 tsc_IV16, u8 *rc4key) |
f0706e82 JB |
107 | { |
108 | u16 ppk[6]; | |
3c838099 | 109 | const u16 *p1k = ctx->p1k; |
f0706e82 JB |
110 | int i; |
111 | ||
112 | ppk[0] = p1k[0]; | |
113 | ppk[1] = p1k[1]; | |
114 | ppk[2] = p1k[2]; | |
115 | ppk[3] = p1k[3]; | |
116 | ppk[4] = p1k[4]; | |
117 | ppk[5] = p1k[4] + tsc_IV16; | |
118 | ||
8c046c8c HH |
119 | ppk[0] += tkipS(ppk[5] ^ get_unaligned_le16(tk + 0)); |
120 | ppk[1] += tkipS(ppk[0] ^ get_unaligned_le16(tk + 2)); | |
121 | ppk[2] += tkipS(ppk[1] ^ get_unaligned_le16(tk + 4)); | |
122 | ppk[3] += tkipS(ppk[2] ^ get_unaligned_le16(tk + 6)); | |
123 | ppk[4] += tkipS(ppk[3] ^ get_unaligned_le16(tk + 8)); | |
124 | ppk[5] += tkipS(ppk[4] ^ get_unaligned_le16(tk + 10)); | |
125 | ppk[0] += ror16(ppk[5] ^ get_unaligned_le16(tk + 12), 1); | |
126 | ppk[1] += ror16(ppk[0] ^ get_unaligned_le16(tk + 14), 1); | |
127 | ppk[2] += ror16(ppk[1], 1); | |
128 | ppk[3] += ror16(ppk[2], 1); | |
129 | ppk[4] += ror16(ppk[3], 1); | |
130 | ppk[5] += ror16(ppk[4], 1); | |
131 | ||
c801242c HH |
132 | rc4key = write_tkip_iv(rc4key, tsc_IV16); |
133 | *rc4key++ = ((ppk[5] ^ get_unaligned_le16(tk)) >> 1) & 0xFF; | |
8c046c8c | 134 | |
8c046c8c HH |
135 | for (i = 0; i < 6; i++) |
136 | put_unaligned_le16(ppk[i], rc4key + 2 * i); | |
f0706e82 JB |
137 | } |
138 | ||
f0706e82 JB |
139 | /* Add TKIP IV and Ext. IV at @pos. @iv0, @iv1, and @iv2 are the first octets |
140 | * of the IV. Returns pointer to the octet following IVs (i.e., beginning of | |
141 | * the packet payload). */ | |
c801242c | 142 | u8 *ieee80211_tkip_add_iv(u8 *pos, struct ieee80211_key *key, u16 iv16) |
f0706e82 | 143 | { |
c801242c | 144 | pos = write_tkip_iv(pos, iv16); |
8f20fc24 | 145 | *pos++ = (key->conf.keyidx << 6) | (1 << 5) /* Ext IV */; |
b0f76b33 | 146 | put_unaligned_le32(key->u.tkip.tx.iv32, pos); |
8c046c8c | 147 | return pos + 4; |
f0706e82 JB |
148 | } |
149 | ||
5d2cdcd4 EG |
150 | void ieee80211_get_tkip_key(struct ieee80211_key_conf *keyconf, |
151 | struct sk_buff *skb, enum ieee80211_tkip_key_type type, | |
152 | u8 *outkey) | |
153 | { | |
154 | struct ieee80211_key *key = (struct ieee80211_key *) | |
155 | container_of(keyconf, struct ieee80211_key, conf); | |
c644bce9 HH |
156 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; |
157 | u8 *data; | |
158 | const u8 *tk; | |
159 | struct tkip_ctx *ctx; | |
5d2cdcd4 EG |
160 | u16 iv16; |
161 | u32 iv32; | |
162 | ||
c644bce9 HH |
163 | data = (u8 *)hdr + ieee80211_hdrlen(hdr->frame_control); |
164 | iv16 = data[2] | (data[0] << 8); | |
165 | iv32 = get_unaligned_le32(&data[4]); | |
166 | ||
ffd7891d | 167 | tk = &key->conf.key[NL80211_TKIP_DATA_OFFSET_ENCR_KEY]; |
c644bce9 | 168 | ctx = &key->u.tkip.tx; |
5d2cdcd4 | 169 | |
9ae705cf | 170 | #ifdef CONFIG_MAC80211_TKIP_DEBUG |
5d2cdcd4 EG |
171 | printk(KERN_DEBUG "TKIP encrypt: iv16 = 0x%04x, iv32 = 0x%08x\n", |
172 | iv16, iv32); | |
173 | ||
c644bce9 | 174 | if (iv32 != ctx->iv32) { |
5d2cdcd4 | 175 | printk(KERN_DEBUG "skb: iv32 = 0x%08x key: iv32 = 0x%08x\n", |
c644bce9 | 176 | iv32, ctx->iv32); |
5d2cdcd4 EG |
177 | printk(KERN_DEBUG "Wrap around of iv16 in the middle of a " |
178 | "fragmented packet\n"); | |
179 | } | |
9ae705cf | 180 | #endif |
5d2cdcd4 EG |
181 | |
182 | /* Update the p1k only when the iv16 in the packet wraps around, this | |
183 | * might occur after the wrap around of iv16 in the key in case of | |
184 | * fragmented packets. */ | |
c644bce9 HH |
185 | if (iv16 == 0 || !ctx->initialized) |
186 | tkip_mixing_phase1(tk, ctx, hdr->addr2, iv32); | |
5d2cdcd4 EG |
187 | |
188 | if (type == IEEE80211_TKIP_P1_KEY) { | |
c644bce9 | 189 | memcpy(outkey, ctx->p1k, sizeof(u16) * 5); |
5d2cdcd4 EG |
190 | return; |
191 | } | |
192 | ||
c644bce9 | 193 | tkip_mixing_phase2(tk, ctx, iv16, outkey); |
5d2cdcd4 EG |
194 | } |
195 | EXPORT_SYMBOL(ieee80211_get_tkip_key); | |
196 | ||
f0706e82 JB |
197 | /* Encrypt packet payload with TKIP using @key. @pos is a pointer to the |
198 | * beginning of the buffer containing payload. This payload must include | |
199 | * headroom of eight octets for IV and Ext. IV and taildroom of four octets | |
200 | * for ICV. @payload_len is the length of payload (_not_ including extra | |
201 | * headroom and tailroom). @ta is the transmitter addresses. */ | |
202 | void ieee80211_tkip_encrypt_data(struct crypto_blkcipher *tfm, | |
203 | struct ieee80211_key *key, | |
204 | u8 *pos, size_t payload_len, u8 *ta) | |
205 | { | |
206 | u8 rc4key[16]; | |
7c70537f | 207 | struct tkip_ctx *ctx = &key->u.tkip.tx; |
ffd7891d | 208 | const u8 *tk = &key->conf.key[NL80211_TKIP_DATA_OFFSET_ENCR_KEY]; |
7c70537f HH |
209 | |
210 | /* Calculate per-packet key */ | |
211 | if (ctx->iv16 == 0 || !ctx->initialized) | |
212 | tkip_mixing_phase1(tk, ctx, ta, ctx->iv32); | |
213 | ||
214 | tkip_mixing_phase2(tk, ctx, ctx->iv16, rc4key); | |
f0706e82 | 215 | |
c801242c | 216 | pos = ieee80211_tkip_add_iv(pos, key, key->u.tkip.tx.iv16); |
f0706e82 JB |
217 | ieee80211_wep_encrypt_data(tfm, rc4key, 16, pos, payload_len); |
218 | } | |
219 | ||
f0706e82 JB |
220 | /* Decrypt packet payload with TKIP using @key. @pos is a pointer to the |
221 | * beginning of the buffer containing IEEE 802.11 header payload, i.e., | |
222 | * including IV, Ext. IV, real data, Michael MIC, ICV. @payload_len is the | |
223 | * length of payload, including IV, Ext. IV, MIC, ICV. */ | |
224 | int ieee80211_tkip_decrypt_data(struct crypto_blkcipher *tfm, | |
225 | struct ieee80211_key *key, | |
226 | u8 *payload, size_t payload_len, u8 *ta, | |
9ae4fda3 | 227 | u8 *ra, int only_iv, int queue, |
50741ae0 | 228 | u32 *out_iv32, u16 *out_iv16) |
f0706e82 JB |
229 | { |
230 | u32 iv32; | |
231 | u32 iv16; | |
232 | u8 rc4key[16], keyid, *pos = payload; | |
233 | int res; | |
ffd7891d | 234 | const u8 *tk = &key->conf.key[NL80211_TKIP_DATA_OFFSET_ENCR_KEY]; |
f0706e82 JB |
235 | |
236 | if (payload_len < 12) | |
237 | return -1; | |
238 | ||
239 | iv16 = (pos[0] << 8) | pos[2]; | |
240 | keyid = pos[3]; | |
8c046c8c | 241 | iv32 = get_unaligned_le32(pos + 4); |
f0706e82 | 242 | pos += 8; |
9ae705cf | 243 | #ifdef CONFIG_MAC80211_TKIP_DEBUG |
f0706e82 JB |
244 | { |
245 | int i; | |
246 | printk(KERN_DEBUG "TKIP decrypt: data(len=%zd)", payload_len); | |
247 | for (i = 0; i < payload_len; i++) | |
248 | printk(" %02x", payload[i]); | |
249 | printk("\n"); | |
250 | printk(KERN_DEBUG "TKIP decrypt: iv16=%04x iv32=%08x\n", | |
251 | iv16, iv32); | |
252 | } | |
9ae705cf | 253 | #endif |
f0706e82 JB |
254 | |
255 | if (!(keyid & (1 << 5))) | |
256 | return TKIP_DECRYPT_NO_EXT_IV; | |
257 | ||
8f20fc24 | 258 | if ((keyid >> 6) != key->conf.keyidx) |
f0706e82 JB |
259 | return TKIP_DECRYPT_INVALID_KEYIDX; |
260 | ||
b0f76b33 HH |
261 | if (key->u.tkip.rx[queue].initialized && |
262 | (iv32 < key->u.tkip.rx[queue].iv32 || | |
263 | (iv32 == key->u.tkip.rx[queue].iv32 && | |
264 | iv16 <= key->u.tkip.rx[queue].iv16))) { | |
9ae705cf | 265 | #ifdef CONFIG_MAC80211_TKIP_DEBUG |
f0706e82 | 266 | printk(KERN_DEBUG "TKIP replay detected for RX frame from " |
0c68ae26 JB |
267 | "%pM (RX IV (%04x,%02x) <= prev. IV (%04x,%02x)\n", |
268 | ta, | |
b0f76b33 HH |
269 | iv32, iv16, key->u.tkip.rx[queue].iv32, |
270 | key->u.tkip.rx[queue].iv16); | |
9ae705cf | 271 | #endif |
f0706e82 JB |
272 | return TKIP_DECRYPT_REPLAY; |
273 | } | |
274 | ||
275 | if (only_iv) { | |
276 | res = TKIP_DECRYPT_OK; | |
b0f76b33 | 277 | key->u.tkip.rx[queue].initialized = 1; |
f0706e82 JB |
278 | goto done; |
279 | } | |
280 | ||
b0f76b33 HH |
281 | if (!key->u.tkip.rx[queue].initialized || |
282 | key->u.tkip.rx[queue].iv32 != iv32) { | |
f0706e82 | 283 | /* IV16 wrapped around - perform TKIP phase 1 */ |
7c70537f | 284 | tkip_mixing_phase1(tk, &key->u.tkip.rx[queue], ta, iv32); |
9ae705cf | 285 | #ifdef CONFIG_MAC80211_TKIP_DEBUG |
f0706e82 JB |
286 | { |
287 | int i; | |
ffd7891d | 288 | u8 key_offset = NL80211_TKIP_DATA_OFFSET_ENCR_KEY; |
0c68ae26 JB |
289 | printk(KERN_DEBUG "TKIP decrypt: Phase1 TA=%pM" |
290 | " TK=", ta); | |
f0706e82 JB |
291 | for (i = 0; i < 16; i++) |
292 | printk("%02x ", | |
ffd7891d | 293 | key->conf.key[key_offset + i]); |
f0706e82 JB |
294 | printk("\n"); |
295 | printk(KERN_DEBUG "TKIP decrypt: P1K="); | |
296 | for (i = 0; i < 5; i++) | |
b0f76b33 | 297 | printk("%04x ", key->u.tkip.rx[queue].p1k[i]); |
f0706e82 JB |
298 | printk("\n"); |
299 | } | |
9ae705cf | 300 | #endif |
9ae4fda3 EG |
301 | if (key->local->ops->update_tkip_key && |
302 | key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) { | |
303 | u8 bcast[ETH_ALEN] = | |
304 | {0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; | |
17741cdc | 305 | u8 *sta_addr = key->sta->sta.addr; |
9ae4fda3 EG |
306 | |
307 | if (is_multicast_ether_addr(ra)) | |
308 | sta_addr = bcast; | |
309 | ||
310 | key->local->ops->update_tkip_key( | |
311 | local_to_hw(key->local), &key->conf, | |
b0f76b33 | 312 | sta_addr, iv32, key->u.tkip.rx[queue].p1k); |
9ae4fda3 | 313 | } |
f0706e82 JB |
314 | } |
315 | ||
7c70537f | 316 | tkip_mixing_phase2(tk, &key->u.tkip.rx[queue], iv16, rc4key); |
9ae705cf | 317 | #ifdef CONFIG_MAC80211_TKIP_DEBUG |
f0706e82 JB |
318 | { |
319 | int i; | |
320 | printk(KERN_DEBUG "TKIP decrypt: Phase2 rc4key="); | |
321 | for (i = 0; i < 16; i++) | |
322 | printk("%02x ", rc4key[i]); | |
323 | printk("\n"); | |
324 | } | |
9ae705cf | 325 | #endif |
f0706e82 JB |
326 | |
327 | res = ieee80211_wep_decrypt_data(tfm, rc4key, 16, pos, payload_len - 12); | |
328 | done: | |
329 | if (res == TKIP_DECRYPT_OK) { | |
50741ae0 JB |
330 | /* |
331 | * Record previously received IV, will be copied into the | |
332 | * key information after MIC verification. It is possible | |
333 | * that we don't catch replays of fragments but that's ok | |
334 | * because the Michael MIC verication will then fail. | |
335 | */ | |
336 | *out_iv32 = iv32; | |
337 | *out_iv16 = iv16; | |
f0706e82 JB |
338 | } |
339 | ||
340 | return res; | |
341 | } |