1 /*
2 * wpa_supplicant - WPA/RSN IE and KDE processing
3 * Copyright (c) 2003-2008, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "includes.h"
10
11 #include "common.h"
12 #include "wpa.h"
13 #include "pmksa_cache.h"
14 #include "common/ieee802_11_defs.h"
15 #include "wpa_i.h"
16 #include "wpa_ie.h"
17
18
19 /**
20 * wpa_parse_wpa_ie - Parse WPA/RSN IE
21 * @wpa_ie: Pointer to WPA or RSN IE
22 * @wpa_ie_len: Length of the WPA/RSN IE
23 * @data: Pointer to data area for parsing results
24 * Returns: 0 on success, -1 on failure
25 *
26 * Parse the contents of WPA or RSN IE and write the parsed data into data.
27 */
wpa_parse_wpa_ie(const u8 * wpa_ie,size_t wpa_ie_len,struct wpa_ie_data * data)28 int wpa_parse_wpa_ie(const u8 *wpa_ie, size_t wpa_ie_len,
29 struct wpa_ie_data *data)
30 {
31 if (wpa_ie_len >= 1 && wpa_ie[0] == WLAN_EID_RSN)
32 return wpa_parse_wpa_ie_rsn(wpa_ie, wpa_ie_len, data);
33 else
34 return wpa_parse_wpa_ie_wpa(wpa_ie, wpa_ie_len, data);
35 }
36
37
wpa_gen_wpa_ie_wpa(u8 * wpa_ie,size_t wpa_ie_len,int pairwise_cipher,int group_cipher,int key_mgmt)38 static int wpa_gen_wpa_ie_wpa(u8 *wpa_ie, size_t wpa_ie_len,
39 int pairwise_cipher, int group_cipher,
40 int key_mgmt)
41 {
42 u8 *pos;
43 struct wpa_ie_hdr *hdr;
44 u32 suite;
45
46 if (wpa_ie_len < sizeof(*hdr) + WPA_SELECTOR_LEN +
47 2 + WPA_SELECTOR_LEN + 2 + WPA_SELECTOR_LEN)
48 return -1;
49
50 hdr = (struct wpa_ie_hdr *) wpa_ie;
51 hdr->elem_id = WLAN_EID_VENDOR_SPECIFIC;
52 RSN_SELECTOR_PUT(hdr->oui, WPA_OUI_TYPE);
53 WPA_PUT_LE16(hdr->version, WPA_VERSION);
54 pos = (u8 *) (hdr + 1);
55
56 suite = wpa_cipher_to_suite(WPA_PROTO_WPA, group_cipher);
57 if (suite == 0) {
58 wpa_printf(MSG_WARNING, "Invalid group cipher (%d).",
59 group_cipher);
60 return -1;
61 }
62 RSN_SELECTOR_PUT(pos, suite);
63 pos += WPA_SELECTOR_LEN;
64
65 *pos++ = 1;
66 *pos++ = 0;
67 suite = wpa_cipher_to_suite(WPA_PROTO_WPA, pairwise_cipher);
68 if (suite == 0 ||
69 (!wpa_cipher_valid_pairwise(pairwise_cipher) &&
70 pairwise_cipher != WPA_CIPHER_NONE)) {
71 wpa_printf(MSG_WARNING, "Invalid pairwise cipher (%d).",
72 pairwise_cipher);
73 return -1;
74 }
75 RSN_SELECTOR_PUT(pos, suite);
76 pos += WPA_SELECTOR_LEN;
77
78 *pos++ = 1;
79 *pos++ = 0;
80 if (key_mgmt == WPA_KEY_MGMT_IEEE8021X) {
81 RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_UNSPEC_802_1X);
82 } else if (key_mgmt == WPA_KEY_MGMT_PSK) {
83 RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_PSK_OVER_802_1X);
84 } else if (key_mgmt == WPA_KEY_MGMT_WPA_NONE) {
85 RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_NONE);
86 } else {
87 wpa_printf(MSG_WARNING, "Invalid key management type (%d).",
88 key_mgmt);
89 return -1;
90 }
91 pos += WPA_SELECTOR_LEN;
92
93 /* WPA Capabilities; use defaults, so no need to include it */
94
95 hdr->len = (pos - wpa_ie) - 2;
96
97 WPA_ASSERT((size_t) (pos - wpa_ie) <= wpa_ie_len);
98
99 return pos - wpa_ie;
100 }
101
102
wpa_gen_wpa_ie_rsn(u8 * rsn_ie,size_t rsn_ie_len,int pairwise_cipher,int group_cipher,int key_mgmt,int mgmt_group_cipher,struct wpa_sm * sm)103 static int wpa_gen_wpa_ie_rsn(u8 *rsn_ie, size_t rsn_ie_len,
104 int pairwise_cipher, int group_cipher,
105 int key_mgmt, int mgmt_group_cipher,
106 struct wpa_sm *sm)
107 {
108 #ifndef CONFIG_NO_WPA2
109 u8 *pos;
110 struct rsn_ie_hdr *hdr;
111 u16 capab;
112 u32 suite;
113
114 if (rsn_ie_len < sizeof(*hdr) + RSN_SELECTOR_LEN +
115 2 + RSN_SELECTOR_LEN + 2 + RSN_SELECTOR_LEN + 2 +
116 (sm->cur_pmksa ? 2 + PMKID_LEN : 0)) {
117 wpa_printf(MSG_DEBUG, "RSN: Too short IE buffer (%lu bytes)",
118 (unsigned long) rsn_ie_len);
119 return -1;
120 }
121
122 hdr = (struct rsn_ie_hdr *) rsn_ie;
123 hdr->elem_id = WLAN_EID_RSN;
124 WPA_PUT_LE16(hdr->version, RSN_VERSION);
125 pos = (u8 *) (hdr + 1);
126
127 suite = wpa_cipher_to_suite(WPA_PROTO_RSN, group_cipher);
128 if (suite == 0) {
129 wpa_printf(MSG_WARNING, "Invalid group cipher (%d).",
130 group_cipher);
131 return -1;
132 }
133 RSN_SELECTOR_PUT(pos, suite);
134 pos += RSN_SELECTOR_LEN;
135
136 *pos++ = 1;
137 *pos++ = 0;
138 suite = wpa_cipher_to_suite(WPA_PROTO_RSN, pairwise_cipher);
139 if (suite == 0 ||
140 (!wpa_cipher_valid_pairwise(pairwise_cipher) &&
141 pairwise_cipher != WPA_CIPHER_NONE)) {
142 wpa_printf(MSG_WARNING, "Invalid pairwise cipher (%d).",
143 pairwise_cipher);
144 return -1;
145 }
146 RSN_SELECTOR_PUT(pos, suite);
147 pos += RSN_SELECTOR_LEN;
148
149 *pos++ = 1;
150 *pos++ = 0;
151 if (key_mgmt == WPA_KEY_MGMT_IEEE8021X) {
152 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_UNSPEC_802_1X);
153 } else if (key_mgmt == WPA_KEY_MGMT_PSK) {
154 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_OVER_802_1X);
155 #ifdef CONFIG_IEEE80211R
156 } else if (key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X) {
157 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
158 } else if (key_mgmt == WPA_KEY_MGMT_FT_PSK) {
159 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
160 #endif /* CONFIG_IEEE80211R */
161 #ifdef CONFIG_IEEE80211W
162 } else if (key_mgmt == WPA_KEY_MGMT_IEEE8021X_SHA256) {
163 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_802_1X_SHA256);
164 } else if (key_mgmt == WPA_KEY_MGMT_PSK_SHA256) {
165 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_SHA256);
166 #endif /* CONFIG_IEEE80211W */
167 } else {
168 wpa_printf(MSG_WARNING, "Invalid key management type (%d).",
169 key_mgmt);
170 return -1;
171 }
172 pos += RSN_SELECTOR_LEN;
173
174 /* RSN Capabilities */
175 capab = 0;
176 #ifdef CONFIG_IEEE80211W
177 if (sm->mfp)
178 capab |= WPA_CAPABILITY_MFPC;
179 if (sm->mfp == 2)
180 capab |= WPA_CAPABILITY_MFPR;
181 #endif /* CONFIG_IEEE80211W */
182 WPA_PUT_LE16(pos, capab);
183 pos += 2;
184
185 if (sm->cur_pmksa) {
186 /* PMKID Count (2 octets, little endian) */
187 *pos++ = 1;
188 *pos++ = 0;
189 /* PMKID */
190 os_memcpy(pos, sm->cur_pmksa->pmkid, PMKID_LEN);
191 pos += PMKID_LEN;
192 }
193
194 #ifdef CONFIG_IEEE80211W
195 if (mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
196 if (!sm->cur_pmksa) {
197 /* PMKID Count */
198 WPA_PUT_LE16(pos, 0);
199 pos += 2;
200 }
201
202 /* Management Group Cipher Suite */
203 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
204 pos += RSN_SELECTOR_LEN;
205 }
206 #endif /* CONFIG_IEEE80211W */
207
208 hdr->len = (pos - rsn_ie) - 2;
209
210 WPA_ASSERT((size_t) (pos - rsn_ie) <= rsn_ie_len);
211
212 return pos - rsn_ie;
213 #else /* CONFIG_NO_WPA2 */
214 return -1;
215 #endif /* CONFIG_NO_WPA2 */
216 }
217
218
219 /**
220 * wpa_gen_wpa_ie - Generate WPA/RSN IE based on current security policy
221 * @sm: Pointer to WPA state machine data from wpa_sm_init()
222 * @wpa_ie: Pointer to memory area for the generated WPA/RSN IE
223 * @wpa_ie_len: Maximum length of the generated WPA/RSN IE
224 * Returns: Length of the generated WPA/RSN IE or -1 on failure
225 */
wpa_gen_wpa_ie(struct wpa_sm * sm,u8 * wpa_ie,size_t wpa_ie_len)226 int wpa_gen_wpa_ie(struct wpa_sm *sm, u8 *wpa_ie, size_t wpa_ie_len)
227 {
228 if (sm->proto == WPA_PROTO_RSN)
229 return wpa_gen_wpa_ie_rsn(wpa_ie, wpa_ie_len,
230 sm->pairwise_cipher,
231 sm->group_cipher,
232 sm->key_mgmt, sm->mgmt_group_cipher,
233 sm);
234 else
235 return wpa_gen_wpa_ie_wpa(wpa_ie, wpa_ie_len,
236 sm->pairwise_cipher,
237 sm->group_cipher,
238 sm->key_mgmt);
239 }
240
241
242 /**
243 * wpa_parse_generic - Parse EAPOL-Key Key Data Generic IEs
244 * @pos: Pointer to the IE header
245 * @end: Pointer to the end of the Key Data buffer
246 * @ie: Pointer to parsed IE data
247 * Returns: 0 on success, 1 if end mark is found, -1 on failure
248 */
wpa_parse_generic(const u8 * pos,const u8 * end,struct wpa_eapol_ie_parse * ie)249 static int wpa_parse_generic(const u8 *pos, const u8 *end,
250 struct wpa_eapol_ie_parse *ie)
251 {
252 if (pos[1] == 0)
253 return 1;
254
255 if (pos[1] >= 6 &&
256 RSN_SELECTOR_GET(pos + 2) == WPA_OUI_TYPE &&
257 pos[2 + WPA_SELECTOR_LEN] == 1 &&
258 pos[2 + WPA_SELECTOR_LEN + 1] == 0) {
259 ie->wpa_ie = pos;
260 ie->wpa_ie_len = pos[1] + 2;
261 wpa_hexdump(MSG_DEBUG, "WPA: WPA IE in EAPOL-Key",
262 ie->wpa_ie, ie->wpa_ie_len);
263 return 0;
264 }
265
266 if (pos + 1 + RSN_SELECTOR_LEN < end &&
267 pos[1] >= RSN_SELECTOR_LEN + PMKID_LEN &&
268 RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_PMKID) {
269 ie->pmkid = pos + 2 + RSN_SELECTOR_LEN;
270 wpa_hexdump(MSG_DEBUG, "WPA: PMKID in EAPOL-Key",
271 pos, pos[1] + 2);
272 return 0;
273 }
274
275 if (pos[1] > RSN_SELECTOR_LEN + 2 &&
276 RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_GROUPKEY) {
277 ie->gtk = pos + 2 + RSN_SELECTOR_LEN;
278 ie->gtk_len = pos[1] - RSN_SELECTOR_LEN;
279 wpa_hexdump_key(MSG_DEBUG, "WPA: GTK in EAPOL-Key",
280 pos, pos[1] + 2);
281 return 0;
282 }
283
284 if (pos[1] > RSN_SELECTOR_LEN + 2 &&
285 RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_MAC_ADDR) {
286 ie->mac_addr = pos + 2 + RSN_SELECTOR_LEN;
287 ie->mac_addr_len = pos[1] - RSN_SELECTOR_LEN;
288 wpa_hexdump(MSG_DEBUG, "WPA: MAC Address in EAPOL-Key",
289 pos, pos[1] + 2);
290 return 0;
291 }
292
293 #ifdef CONFIG_PEERKEY
294 if (pos[1] > RSN_SELECTOR_LEN + 2 &&
295 RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_SMK) {
296 ie->smk = pos + 2 + RSN_SELECTOR_LEN;
297 ie->smk_len = pos[1] - RSN_SELECTOR_LEN;
298 wpa_hexdump_key(MSG_DEBUG, "WPA: SMK in EAPOL-Key",
299 pos, pos[1] + 2);
300 return 0;
301 }
302
303 if (pos[1] > RSN_SELECTOR_LEN + 2 &&
304 RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_NONCE) {
305 ie->nonce = pos + 2 + RSN_SELECTOR_LEN;
306 ie->nonce_len = pos[1] - RSN_SELECTOR_LEN;
307 wpa_hexdump(MSG_DEBUG, "WPA: Nonce in EAPOL-Key",
308 pos, pos[1] + 2);
309 return 0;
310 }
311
312 if (pos[1] > RSN_SELECTOR_LEN + 2 &&
313 RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_LIFETIME) {
314 ie->lifetime = pos + 2 + RSN_SELECTOR_LEN;
315 ie->lifetime_len = pos[1] - RSN_SELECTOR_LEN;
316 wpa_hexdump(MSG_DEBUG, "WPA: Lifetime in EAPOL-Key",
317 pos, pos[1] + 2);
318 return 0;
319 }
320
321 if (pos[1] > RSN_SELECTOR_LEN + 2 &&
322 RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_ERROR) {
323 ie->error = pos + 2 + RSN_SELECTOR_LEN;
324 ie->error_len = pos[1] - RSN_SELECTOR_LEN;
325 wpa_hexdump(MSG_DEBUG, "WPA: Error in EAPOL-Key",
326 pos, pos[1] + 2);
327 return 0;
328 }
329 #endif /* CONFIG_PEERKEY */
330
331 #ifdef CONFIG_IEEE80211W
332 if (pos[1] > RSN_SELECTOR_LEN + 2 &&
333 RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_IGTK) {
334 ie->igtk = pos + 2 + RSN_SELECTOR_LEN;
335 ie->igtk_len = pos[1] - RSN_SELECTOR_LEN;
336 wpa_hexdump_key(MSG_DEBUG, "WPA: IGTK in EAPOL-Key",
337 pos, pos[1] + 2);
338 return 0;
339 }
340 #endif /* CONFIG_IEEE80211W */
341
342 return 0;
343 }
344
345
346 /**
347 * wpa_supplicant_parse_ies - Parse EAPOL-Key Key Data IEs
348 * @buf: Pointer to the Key Data buffer
349 * @len: Key Data Length
350 * @ie: Pointer to parsed IE data
351 * Returns: 0 on success, -1 on failure
352 */
wpa_supplicant_parse_ies(const u8 * buf,size_t len,struct wpa_eapol_ie_parse * ie)353 int wpa_supplicant_parse_ies(const u8 *buf, size_t len,
354 struct wpa_eapol_ie_parse *ie)
355 {
356 const u8 *pos, *end;
357 int ret = 0;
358
359 os_memset(ie, 0, sizeof(*ie));
360 for (pos = buf, end = pos + len; pos + 1 < end; pos += 2 + pos[1]) {
361 if (pos[0] == 0xdd &&
362 ((pos == buf + len - 1) || pos[1] == 0)) {
363 /* Ignore padding */
364 break;
365 }
366 if (pos + 2 + pos[1] > end) {
367 wpa_printf(MSG_DEBUG, "WPA: EAPOL-Key Key Data "
368 "underflow (ie=%d len=%d pos=%d)",
369 pos[0], pos[1], (int) (pos - buf));
370 wpa_hexdump_key(MSG_DEBUG, "WPA: Key Data",
371 buf, len);
372 ret = -1;
373 break;
374 }
375 if (*pos == WLAN_EID_RSN) {
376 ie->rsn_ie = pos;
377 ie->rsn_ie_len = pos[1] + 2;
378 wpa_hexdump(MSG_DEBUG, "WPA: RSN IE in EAPOL-Key",
379 ie->rsn_ie, ie->rsn_ie_len);
380 } else if (*pos == WLAN_EID_MOBILITY_DOMAIN) {
381 ie->mdie = pos;
382 ie->mdie_len = pos[1] + 2;
383 wpa_hexdump(MSG_DEBUG, "WPA: MDIE in EAPOL-Key",
384 ie->mdie, ie->mdie_len);
385 } else if (*pos == WLAN_EID_FAST_BSS_TRANSITION) {
386 ie->ftie = pos;
387 ie->ftie_len = pos[1] + 2;
388 wpa_hexdump(MSG_DEBUG, "WPA: FTIE in EAPOL-Key",
389 ie->ftie, ie->ftie_len);
390 } else if (*pos == WLAN_EID_TIMEOUT_INTERVAL && pos[1] >= 5) {
391 if (pos[2] == WLAN_TIMEOUT_REASSOC_DEADLINE) {
392 ie->reassoc_deadline = pos;
393 wpa_hexdump(MSG_DEBUG, "WPA: Reassoc Deadline "
394 "in EAPOL-Key",
395 ie->reassoc_deadline, pos[1] + 2);
396 } else if (pos[2] == WLAN_TIMEOUT_KEY_LIFETIME) {
397 ie->key_lifetime = pos;
398 wpa_hexdump(MSG_DEBUG, "WPA: KeyLifetime "
399 "in EAPOL-Key",
400 ie->key_lifetime, pos[1] + 2);
401 } else {
402 wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized "
403 "EAPOL-Key Key Data IE",
404 pos, 2 + pos[1]);
405 }
406 } else if (*pos == WLAN_EID_LINK_ID) {
407 if (pos[1] >= 18) {
408 ie->lnkid = pos;
409 ie->lnkid_len = pos[1] + 2;
410 }
411 } else if (*pos == WLAN_EID_EXT_CAPAB) {
412 ie->ext_capab = pos;
413 ie->ext_capab_len = pos[1] + 2;
414 } else if (*pos == WLAN_EID_SUPP_RATES) {
415 ie->supp_rates = pos;
416 ie->supp_rates_len = pos[1] + 2;
417 } else if (*pos == WLAN_EID_EXT_SUPP_RATES) {
418 ie->ext_supp_rates = pos;
419 ie->ext_supp_rates_len = pos[1] + 2;
420 } else if (*pos == WLAN_EID_VENDOR_SPECIFIC) {
421 ret = wpa_parse_generic(pos, end, ie);
422 if (ret < 0)
423 break;
424 if (ret > 0) {
425 ret = 0;
426 break;
427 }
428 } else {
429 wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized EAPOL-Key "
430 "Key Data IE", pos, 2 + pos[1]);
431 }
432 }
433
434 return ret;
435 }
436