]>
git.ipfire.org Git - thirdparty/hostap.git/blob - wlantest/tkip.c
2 * Temporal Key Integrity Protocol (CCMP)
3 * Copyright (c) 2010, Jouni Malinen <j@w1.fi>
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
9 #include "utils/includes.h"
11 #include "utils/common.h"
12 #include "utils/crc32.h"
13 #include "common/ieee802_11_defs.h"
17 void wep_crypt(u8
*key
, u8
*buf
, size_t plen
);
20 static inline u16
RotR1(u16 val
)
22 return (val
>> 1) | (val
<< 15);
26 static inline u8
Lo8(u16 val
)
32 static inline u8
Hi8(u16 val
)
38 static inline u16
Lo16(u32 val
)
44 static inline u16
Hi16(u32 val
)
50 static inline u16
Mk16(u8 hi
, u8 lo
)
52 return lo
| (((u16
) hi
) << 8);
56 static inline u16
Mk16_le(u16
*v
)
58 return le_to_host16(*v
);
62 static const u16 Sbox
[256] =
64 0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154,
65 0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A,
66 0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B,
67 0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B,
68 0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F,
69 0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F,
70 0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5,
71 0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F,
72 0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB,
73 0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397,
74 0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED,
75 0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A,
76 0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194,
77 0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3,
78 0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104,
79 0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D,
80 0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39,
81 0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695,
82 0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83,
83 0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76,
84 0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4,
85 0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B,
86 0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0,
87 0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018,
88 0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751,
89 0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85,
90 0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12,
91 0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9,
92 0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7,
93 0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A,
94 0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8,
95 0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A,
99 static inline u16
_S_(u16 v
)
101 u16 t
= Sbox
[Hi8(v
)];
102 return Sbox
[Lo8(v
)] ^ ((t
<< 8) | (t
>> 8));
106 #define PHASE1_LOOP_COUNT 8
108 static void tkip_mixing_phase1(u16
*TTAK
, const u8
*TK
, const u8
*TA
, u32 IV32
)
112 /* Initialize the 80-bit TTAK from TSC (IV32) and TA[0..5] */
113 TTAK
[0] = Lo16(IV32
);
114 TTAK
[1] = Hi16(IV32
);
115 TTAK
[2] = Mk16(TA
[1], TA
[0]);
116 TTAK
[3] = Mk16(TA
[3], TA
[2]);
117 TTAK
[4] = Mk16(TA
[5], TA
[4]);
119 for (i
= 0; i
< PHASE1_LOOP_COUNT
; i
++) {
121 TTAK
[0] += _S_(TTAK
[4] ^ Mk16(TK
[1 + j
], TK
[0 + j
]));
122 TTAK
[1] += _S_(TTAK
[0] ^ Mk16(TK
[5 + j
], TK
[4 + j
]));
123 TTAK
[2] += _S_(TTAK
[1] ^ Mk16(TK
[9 + j
], TK
[8 + j
]));
124 TTAK
[3] += _S_(TTAK
[2] ^ Mk16(TK
[13 + j
], TK
[12 + j
]));
125 TTAK
[4] += _S_(TTAK
[3] ^ Mk16(TK
[1 + j
], TK
[0 + j
])) + i
;
130 static void tkip_mixing_phase2(u8
*WEPSeed
, const u8
*TK
, const u16
*TTAK
,
135 /* Step 1 - make copy of TTAK and bring in TSC */
141 PPK
[5] = TTAK
[4] + IV16
;
143 /* Step 2 - 96-bit bijective mixing using S-box */
144 PPK
[0] += _S_(PPK
[5] ^ Mk16_le((u16
*) &TK
[0]));
145 PPK
[1] += _S_(PPK
[0] ^ Mk16_le((u16
*) &TK
[2]));
146 PPK
[2] += _S_(PPK
[1] ^ Mk16_le((u16
*) &TK
[4]));
147 PPK
[3] += _S_(PPK
[2] ^ Mk16_le((u16
*) &TK
[6]));
148 PPK
[4] += _S_(PPK
[3] ^ Mk16_le((u16
*) &TK
[8]));
149 PPK
[5] += _S_(PPK
[4] ^ Mk16_le((u16
*) &TK
[10]));
151 PPK
[0] += RotR1(PPK
[5] ^ Mk16_le((u16
*) &TK
[12]));
152 PPK
[1] += RotR1(PPK
[0] ^ Mk16_le((u16
*) &TK
[14]));
153 PPK
[2] += RotR1(PPK
[1]);
154 PPK
[3] += RotR1(PPK
[2]);
155 PPK
[4] += RotR1(PPK
[3]);
156 PPK
[5] += RotR1(PPK
[4]);
158 /* Step 3 - bring in last of TK bits, assign 24-bit WEP IV value
159 * WEPSeed[0..2] is transmitted as WEP IV */
160 WEPSeed
[0] = Hi8(IV16
);
161 WEPSeed
[1] = (Hi8(IV16
) | 0x20) & 0x7F;
162 WEPSeed
[2] = Lo8(IV16
);
163 WEPSeed
[3] = Lo8((PPK
[5] ^ Mk16_le((u16
*) &TK
[0])) >> 1);
164 WPA_PUT_LE16(&WEPSeed
[4], PPK
[0]);
165 WPA_PUT_LE16(&WEPSeed
[6], PPK
[1]);
166 WPA_PUT_LE16(&WEPSeed
[8], PPK
[2]);
167 WPA_PUT_LE16(&WEPSeed
[10], PPK
[3]);
168 WPA_PUT_LE16(&WEPSeed
[12], PPK
[4]);
169 WPA_PUT_LE16(&WEPSeed
[14], PPK
[5]);
173 static inline u32
rotl(u32 val
, int bits
)
175 return (val
<< bits
) | (val
>> (32 - bits
));
179 static inline u32
rotr(u32 val
, int bits
)
181 return (val
>> bits
) | (val
<< (32 - bits
));
185 static inline u32
xswap(u32 val
)
187 return ((val
& 0x00ff00ff) << 8) | ((val
& 0xff00ff00) >> 8);
191 #define michael_block(l, r) \
204 static void michael_mic(const u8
*key
, const u8
*hdr
, const u8
*data
,
205 size_t data_len
, u8
*mic
)
210 l
= WPA_GET_LE32(key
);
211 r
= WPA_GET_LE32(key
+ 4);
213 /* Michael MIC pseudo header: DA, SA, 3 x 0, Priority */
214 l
^= WPA_GET_LE32(hdr
);
216 l
^= WPA_GET_LE32(&hdr
[4]);
218 l
^= WPA_GET_LE32(&hdr
[8]);
220 l
^= WPA_GET_LE32(&hdr
[12]);
223 /* 32-bit blocks of data */
224 blocks
= data_len
/ 4;
226 for (i
= 0; i
< blocks
; i
++) {
227 l
^= WPA_GET_LE32(&data
[4 * i
]);
231 /* Last block and padding (0x5a, 4..7 x 0) */
237 l
^= data
[4 * i
] | 0x5a00;
240 l
^= data
[4 * i
] | (data
[4 * i
+ 1] << 8) | 0x5a0000;
243 l
^= data
[4 * i
] | (data
[4 * i
+ 1] << 8) |
244 (data
[4 * i
+ 2] << 16) | 0x5a000000;
251 WPA_PUT_LE32(mic
, l
);
252 WPA_PUT_LE32(mic
+ 4, r
);
256 static void michael_mic_hdr(const struct ieee80211_hdr
*hdr11
, u8
*hdr
)
259 u16 fc
= le_to_host16(hdr11
->frame_control
);
261 switch (fc
& (WLAN_FC_FROMDS
| WLAN_FC_TODS
)) {
263 os_memcpy(hdr
, hdr11
->addr3
, ETH_ALEN
); /* DA */
264 os_memcpy(hdr
+ ETH_ALEN
, hdr11
->addr2
, ETH_ALEN
); /* SA */
267 os_memcpy(hdr
, hdr11
->addr1
, ETH_ALEN
); /* DA */
268 os_memcpy(hdr
+ ETH_ALEN
, hdr11
->addr3
, ETH_ALEN
); /* SA */
270 case WLAN_FC_FROMDS
| WLAN_FC_TODS
:
271 os_memcpy(hdr
, hdr11
->addr3
, ETH_ALEN
); /* DA */
272 os_memcpy(hdr
+ ETH_ALEN
, hdr11
+ 1, ETH_ALEN
); /* SA */
276 os_memcpy(hdr
, hdr11
->addr1
, ETH_ALEN
); /* DA */
277 os_memcpy(hdr
+ ETH_ALEN
, hdr11
->addr2
, ETH_ALEN
); /* SA */
281 if (WLAN_FC_GET_TYPE(fc
) == WLAN_FC_TYPE_DATA
&&
282 (WLAN_FC_GET_STYPE(fc
) & 0x08)) {
283 const u8
*qos
= ((const u8
*) hdr11
) + hdrlen
;
284 hdr
[12] = qos
[0] & 0x0f; /* priority */
286 hdr
[12] = 0; /* priority */
288 hdr
[13] = hdr
[14] = hdr
[15] = 0; /* reserved */
292 u8
* tkip_decrypt(const u8
*tk
, const struct ieee80211_hdr
*hdr
,
293 const u8
*data
, size_t data_len
, size_t *decrypted_len
)
305 u16 fc
= le_to_host16(hdr
->frame_control
);
307 if (data_len
< 8 + 4)
310 iv16
= (data
[0] << 8) | data
[2];
311 iv32
= WPA_GET_LE32(&data
[4]);
312 wpa_printf(MSG_EXCESSIVE
, "TKIP decrypt: iv32=%08x iv16=%04x",
315 tkip_mixing_phase1(ttak
, tk
, hdr
->addr2
, iv32
);
316 wpa_hexdump(MSG_EXCESSIVE
, "TKIP TTAK", (u8
*) ttak
, sizeof(ttak
));
317 tkip_mixing_phase2(rc4key
, tk
, ttak
, iv16
);
318 wpa_hexdump(MSG_EXCESSIVE
, "TKIP RC4KEY", rc4key
, sizeof(rc4key
));
320 plain_len
= data_len
- 8;
321 plain
= os_memdup(data
+ 8, plain_len
);
324 wep_crypt(rc4key
, plain
, plain_len
);
326 icv
= crc32(plain
, plain_len
- 4);
327 rx_icv
= WPA_GET_LE32(plain
+ plain_len
- 4);
329 wpa_printf(MSG_INFO
, "TKIP ICV mismatch in frame from " MACSTR
,
330 MAC2STR(hdr
->addr2
));
331 wpa_printf(MSG_DEBUG
, "TKIP calculated ICV %08x received ICV "
332 "%08x", icv
, rx_icv
);
338 /* TODO: MSDU reassembly */
341 wpa_printf(MSG_INFO
, "TKIP: Not enough room for Michael MIC "
342 "in a frame from " MACSTR
, MAC2STR(hdr
->addr2
));
347 michael_mic_hdr(hdr
, michael_hdr
);
348 mic_key
= tk
+ ((fc
& WLAN_FC_FROMDS
) ? 16 : 24);
349 michael_mic(mic_key
, michael_hdr
, plain
, plain_len
- 8, mic
);
350 if (os_memcmp(mic
, plain
+ plain_len
- 8, 8) != 0) {
351 wpa_printf(MSG_INFO
, "TKIP: Michael MIC mismatch in a frame "
352 "from " MACSTR
, MAC2STR(hdr
->addr2
));
353 wpa_hexdump(MSG_DEBUG
, "TKIP: Calculated MIC", mic
, 8);
354 wpa_hexdump(MSG_DEBUG
, "TKIP: Received MIC",
355 plain
+ plain_len
- 8, 8);
360 *decrypted_len
= plain_len
- 8;
365 void tkip_get_pn(u8
*pn
, const u8
*data
)
367 pn
[0] = data
[7]; /* PN5 */
368 pn
[1] = data
[6]; /* PN4 */
369 pn
[2] = data
[5]; /* PN3 */
370 pn
[3] = data
[4]; /* PN2 */
371 pn
[4] = data
[0]; /* PN1 */
372 pn
[5] = data
[2]; /* PN0 */
376 u8
* tkip_encrypt(const u8
*tk
, u8
*frame
, size_t len
, size_t hdrlen
, u8
*qos
,
377 u8
*pn
, int keyid
, size_t *encrypted_len
)
381 struct ieee80211_hdr
*hdr
;
390 if (len
< sizeof(*hdr
) || len
< hdrlen
)
392 hdr
= (struct ieee80211_hdr
*) frame
;
393 fc
= le_to_host16(hdr
->frame_control
);
395 michael_mic_hdr(hdr
, michael_hdr
);
396 mic_key
= tk
+ ((fc
& WLAN_FC_FROMDS
) ? 16 : 24);
397 michael_mic(mic_key
, michael_hdr
, frame
+ hdrlen
, len
- hdrlen
, mic
);
398 wpa_hexdump(MSG_EXCESSIVE
, "TKIP: MIC", mic
, sizeof(mic
));
400 iv32
= WPA_GET_BE32(pn
);
401 iv16
= WPA_GET_BE16(pn
+ 4);
402 tkip_mixing_phase1(ttak
, tk
, hdr
->addr2
, iv32
);
403 wpa_hexdump(MSG_EXCESSIVE
, "TKIP TTAK", (u8
*) ttak
, sizeof(ttak
));
404 tkip_mixing_phase2(rc4key
, tk
, ttak
, iv16
);
405 wpa_hexdump(MSG_EXCESSIVE
, "TKIP RC4KEY", rc4key
, sizeof(rc4key
));
407 crypt
= os_malloc(len
+ 8 + sizeof(mic
) + 4);
410 os_memcpy(crypt
, frame
, hdrlen
);
411 pos
= crypt
+ hdrlen
;
412 os_memcpy(pos
, rc4key
, 3);
414 *pos
++ = keyid
<< 6 | BIT(5);
420 os_memcpy(pos
, frame
+ hdrlen
, len
- hdrlen
);
421 os_memcpy(pos
+ len
- hdrlen
, mic
, sizeof(mic
));
422 WPA_PUT_LE32(pos
+ len
- hdrlen
+ sizeof(mic
),
423 crc32(pos
, len
- hdrlen
+ sizeof(mic
)));
424 wep_crypt(rc4key
, pos
, len
- hdrlen
+ sizeof(mic
) + 4);
426 *encrypted_len
= len
+ 8 + sizeof(mic
) + 4;