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  */
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 
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 if (key_mgmt == WPA_KEY_MGMT_CCKM) {
87 		RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_CCKM);
88 	} else {
89 		wpa_printf(MSG_WARNING, "Invalid key management type (%d).",
90 			   key_mgmt);
91 		return -1;
92 	}
93 	pos += WPA_SELECTOR_LEN;
94 
95 	/* WPA Capabilities; use defaults, so no need to include it */
96 
97 	hdr->len = (pos - wpa_ie) - 2;
98 
99 	WPA_ASSERT((size_t) (pos - wpa_ie) <= wpa_ie_len);
100 
101 	return pos - wpa_ie;
102 }
103 
104 
105 static int wpa_gen_wpa_ie_rsn(u8 *rsn_ie, size_t rsn_ie_len,
106 			      int pairwise_cipher, int group_cipher,
107 			      int key_mgmt, int mgmt_group_cipher,
108 			      struct wpa_sm *sm)
109 {
110 	u8 *pos;
111 	struct rsn_ie_hdr *hdr;
112 	u16 capab;
113 	u32 suite;
114 
115 	if (rsn_ie_len < sizeof(*hdr) + RSN_SELECTOR_LEN +
116 	    2 + RSN_SELECTOR_LEN + 2 + RSN_SELECTOR_LEN + 2 +
117 	    (sm->cur_pmksa ? 2 + PMKID_LEN : 0)) {
118 		wpa_printf(MSG_DEBUG, "RSN: Too short IE buffer (%lu bytes)",
119 			   (unsigned long) rsn_ie_len);
120 		return -1;
121 	}
122 
123 	hdr = (struct rsn_ie_hdr *) rsn_ie;
124 	hdr->elem_id = WLAN_EID_RSN;
125 	WPA_PUT_LE16(hdr->version, RSN_VERSION);
126 	pos = (u8 *) (hdr + 1);
127 
128 	suite = wpa_cipher_to_suite(WPA_PROTO_RSN, group_cipher);
129 	if (suite == 0) {
130 		wpa_printf(MSG_WARNING, "Invalid group cipher (%d).",
131 			   group_cipher);
132 		return -1;
133 	}
134 	RSN_SELECTOR_PUT(pos, suite);
135 	pos += RSN_SELECTOR_LEN;
136 
137 	*pos++ = 1;
138 	*pos++ = 0;
139 	suite = wpa_cipher_to_suite(WPA_PROTO_RSN, pairwise_cipher);
140 	if (suite == 0 ||
141 	    (!wpa_cipher_valid_pairwise(pairwise_cipher) &&
142 	     pairwise_cipher != WPA_CIPHER_NONE)) {
143 		wpa_printf(MSG_WARNING, "Invalid pairwise cipher (%d).",
144 			   pairwise_cipher);
145 		return -1;
146 	}
147 	RSN_SELECTOR_PUT(pos, suite);
148 	pos += RSN_SELECTOR_LEN;
149 
150 	*pos++ = 1;
151 	*pos++ = 0;
152 	if (key_mgmt == WPA_KEY_MGMT_IEEE8021X) {
153 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_UNSPEC_802_1X);
154 	} else if (key_mgmt == WPA_KEY_MGMT_PSK) {
155 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_OVER_802_1X);
156 	} else if (key_mgmt == WPA_KEY_MGMT_CCKM) {
157 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_CCKM);
158 #ifdef CONFIG_IEEE80211R
159 	} else if (key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X) {
160 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
161 	} else if (key_mgmt == WPA_KEY_MGMT_FT_PSK) {
162 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
163 #endif /* CONFIG_IEEE80211R */
164 #ifdef CONFIG_IEEE80211W
165 	} else if (key_mgmt == WPA_KEY_MGMT_IEEE8021X_SHA256) {
166 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_802_1X_SHA256);
167 	} else if (key_mgmt == WPA_KEY_MGMT_PSK_SHA256) {
168 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_SHA256);
169 #endif /* CONFIG_IEEE80211W */
170 #ifdef CONFIG_SAE
171 	} else if (key_mgmt == WPA_KEY_MGMT_SAE) {
172 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_SAE);
173 	} else if (key_mgmt == WPA_KEY_MGMT_FT_SAE) {
174 		RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_SAE);
175 #endif /* CONFIG_SAE */
176 	} else {
177 		wpa_printf(MSG_WARNING, "Invalid key management type (%d).",
178 			   key_mgmt);
179 		return -1;
180 	}
181 	pos += RSN_SELECTOR_LEN;
182 
183 	/* RSN Capabilities */
184 	capab = 0;
185 #ifdef CONFIG_IEEE80211W
186 	if (sm->mfp)
187 		capab |= WPA_CAPABILITY_MFPC;
188 	if (sm->mfp == 2)
189 		capab |= WPA_CAPABILITY_MFPR;
190 #endif /* CONFIG_IEEE80211W */
191 	WPA_PUT_LE16(pos, capab);
192 	pos += 2;
193 
194 	if (sm->cur_pmksa) {
195 		/* PMKID Count (2 octets, little endian) */
196 		*pos++ = 1;
197 		*pos++ = 0;
198 		/* PMKID */
199 		os_memcpy(pos, sm->cur_pmksa->pmkid, PMKID_LEN);
200 		pos += PMKID_LEN;
201 	}
202 
203 #ifdef CONFIG_IEEE80211W
204 	if (mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
205 		if (!sm->cur_pmksa) {
206 			/* PMKID Count */
207 			WPA_PUT_LE16(pos, 0);
208 			pos += 2;
209 		}
210 
211 		/* Management Group Cipher Suite */
212 		RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
213 		pos += RSN_SELECTOR_LEN;
214 	}
215 #endif /* CONFIG_IEEE80211W */
216 
217 	hdr->len = (pos - rsn_ie) - 2;
218 
219 	WPA_ASSERT((size_t) (pos - rsn_ie) <= rsn_ie_len);
220 
221 	return pos - rsn_ie;
222 }
223 
224 
225 /**
226  * wpa_gen_wpa_ie - Generate WPA/RSN IE based on current security policy
227  * @sm: Pointer to WPA state machine data from wpa_sm_init()
228  * @wpa_ie: Pointer to memory area for the generated WPA/RSN IE
229  * @wpa_ie_len: Maximum length of the generated WPA/RSN IE
230  * Returns: Length of the generated WPA/RSN IE or -1 on failure
231  */
232 int wpa_gen_wpa_ie(struct wpa_sm *sm, u8 *wpa_ie, size_t wpa_ie_len)
233 {
234 	if (sm->proto == WPA_PROTO_RSN)
235 		return wpa_gen_wpa_ie_rsn(wpa_ie, wpa_ie_len,
236 					  sm->pairwise_cipher,
237 					  sm->group_cipher,
238 					  sm->key_mgmt, sm->mgmt_group_cipher,
239 					  sm);
240 	else
241 		return wpa_gen_wpa_ie_wpa(wpa_ie, wpa_ie_len,
242 					  sm->pairwise_cipher,
243 					  sm->group_cipher,
244 					  sm->key_mgmt);
245 }
246 
247 
248 /**
249  * wpa_parse_generic - Parse EAPOL-Key Key Data Generic IEs
250  * @pos: Pointer to the IE header
251  * @end: Pointer to the end of the Key Data buffer
252  * @ie: Pointer to parsed IE data
253  * Returns: 0 on success, 1 if end mark is found, -1 on failure
254  */
255 static int wpa_parse_generic(const u8 *pos, const u8 *end,
256 			     struct wpa_eapol_ie_parse *ie)
257 {
258 	if (pos[1] == 0)
259 		return 1;
260 
261 	if (pos[1] >= 6 &&
262 	    RSN_SELECTOR_GET(pos + 2) == WPA_OUI_TYPE &&
263 	    pos[2 + WPA_SELECTOR_LEN] == 1 &&
264 	    pos[2 + WPA_SELECTOR_LEN + 1] == 0) {
265 		ie->wpa_ie = pos;
266 		ie->wpa_ie_len = pos[1] + 2;
267 		wpa_hexdump(MSG_DEBUG, "WPA: WPA IE in EAPOL-Key",
268 			    ie->wpa_ie, ie->wpa_ie_len);
269 		return 0;
270 	}
271 
272 	if (pos + 1 + RSN_SELECTOR_LEN < end &&
273 	    pos[1] >= RSN_SELECTOR_LEN + PMKID_LEN &&
274 	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_PMKID) {
275 		ie->pmkid = pos + 2 + RSN_SELECTOR_LEN;
276 		wpa_hexdump(MSG_DEBUG, "WPA: PMKID in EAPOL-Key",
277 			    pos, pos[1] + 2);
278 		return 0;
279 	}
280 
281 	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
282 	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_GROUPKEY) {
283 		ie->gtk = pos + 2 + RSN_SELECTOR_LEN;
284 		ie->gtk_len = pos[1] - RSN_SELECTOR_LEN;
285 		wpa_hexdump_key(MSG_DEBUG, "WPA: GTK in EAPOL-Key",
286 				pos, pos[1] + 2);
287 		return 0;
288 	}
289 
290 	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
291 	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_MAC_ADDR) {
292 		ie->mac_addr = pos + 2 + RSN_SELECTOR_LEN;
293 		ie->mac_addr_len = pos[1] - RSN_SELECTOR_LEN;
294 		wpa_hexdump(MSG_DEBUG, "WPA: MAC Address in EAPOL-Key",
295 			    pos, pos[1] + 2);
296 		return 0;
297 	}
298 
299 #ifdef CONFIG_PEERKEY
300 	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
301 	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_SMK) {
302 		ie->smk = pos + 2 + RSN_SELECTOR_LEN;
303 		ie->smk_len = pos[1] - RSN_SELECTOR_LEN;
304 		wpa_hexdump_key(MSG_DEBUG, "WPA: SMK in EAPOL-Key",
305 				pos, pos[1] + 2);
306 		return 0;
307 	}
308 
309 	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
310 	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_NONCE) {
311 		ie->nonce = pos + 2 + RSN_SELECTOR_LEN;
312 		ie->nonce_len = pos[1] - RSN_SELECTOR_LEN;
313 		wpa_hexdump(MSG_DEBUG, "WPA: Nonce in EAPOL-Key",
314 			    pos, pos[1] + 2);
315 		return 0;
316 	}
317 
318 	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
319 	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_LIFETIME) {
320 		ie->lifetime = pos + 2 + RSN_SELECTOR_LEN;
321 		ie->lifetime_len = pos[1] - RSN_SELECTOR_LEN;
322 		wpa_hexdump(MSG_DEBUG, "WPA: Lifetime in EAPOL-Key",
323 			    pos, pos[1] + 2);
324 		return 0;
325 	}
326 
327 	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
328 	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_ERROR) {
329 		ie->error = pos + 2 + RSN_SELECTOR_LEN;
330 		ie->error_len = pos[1] - RSN_SELECTOR_LEN;
331 		wpa_hexdump(MSG_DEBUG, "WPA: Error in EAPOL-Key",
332 			    pos, pos[1] + 2);
333 		return 0;
334 	}
335 #endif /* CONFIG_PEERKEY */
336 
337 #ifdef CONFIG_IEEE80211W
338 	if (pos[1] > RSN_SELECTOR_LEN + 2 &&
339 	    RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_IGTK) {
340 		ie->igtk = pos + 2 + RSN_SELECTOR_LEN;
341 		ie->igtk_len = pos[1] - RSN_SELECTOR_LEN;
342 		wpa_hexdump_key(MSG_DEBUG, "WPA: IGTK in EAPOL-Key",
343 				pos, pos[1] + 2);
344 		return 0;
345 	}
346 #endif /* CONFIG_IEEE80211W */
347 
348 #ifdef CONFIG_P2P
349 	if (pos[1] >= RSN_SELECTOR_LEN + 1 &&
350 	    RSN_SELECTOR_GET(pos + 2) == WFA_KEY_DATA_IP_ADDR_REQ) {
351 		ie->ip_addr_req = pos + 2 + RSN_SELECTOR_LEN;
352 		wpa_hexdump(MSG_DEBUG, "WPA: IP Address Request in EAPOL-Key",
353 			    ie->ip_addr_req, pos[1] - RSN_SELECTOR_LEN);
354 		return 0;
355 	}
356 
357 	if (pos[1] >= RSN_SELECTOR_LEN + 3 * 4 &&
358 	    RSN_SELECTOR_GET(pos + 2) == WFA_KEY_DATA_IP_ADDR_ALLOC) {
359 		ie->ip_addr_alloc = pos + 2 + RSN_SELECTOR_LEN;
360 		wpa_hexdump(MSG_DEBUG,
361 			    "WPA: IP Address Allocation in EAPOL-Key",
362 			    ie->ip_addr_alloc, pos[1] - RSN_SELECTOR_LEN);
363 		return 0;
364 	}
365 #endif /* CONFIG_P2P */
366 
367 	return 0;
368 }
369 
370 
371 /**
372  * wpa_supplicant_parse_ies - Parse EAPOL-Key Key Data IEs
373  * @buf: Pointer to the Key Data buffer
374  * @len: Key Data Length
375  * @ie: Pointer to parsed IE data
376  * Returns: 0 on success, -1 on failure
377  */
378 int wpa_supplicant_parse_ies(const u8 *buf, size_t len,
379 			     struct wpa_eapol_ie_parse *ie)
380 {
381 	const u8 *pos, *end;
382 	int ret = 0;
383 
384 	os_memset(ie, 0, sizeof(*ie));
385 	for (pos = buf, end = pos + len; pos + 1 < end; pos += 2 + pos[1]) {
386 		if (pos[0] == 0xdd &&
387 		    ((pos == buf + len - 1) || pos[1] == 0)) {
388 			/* Ignore padding */
389 			break;
390 		}
391 		if (pos + 2 + pos[1] > end) {
392 			wpa_printf(MSG_DEBUG, "WPA: EAPOL-Key Key Data "
393 				   "underflow (ie=%d len=%d pos=%d)",
394 				   pos[0], pos[1], (int) (pos - buf));
395 			wpa_hexdump_key(MSG_DEBUG, "WPA: Key Data",
396 					buf, len);
397 			ret = -1;
398 			break;
399 		}
400 		if (*pos == WLAN_EID_RSN) {
401 			ie->rsn_ie = pos;
402 			ie->rsn_ie_len = pos[1] + 2;
403 			wpa_hexdump(MSG_DEBUG, "WPA: RSN IE in EAPOL-Key",
404 				    ie->rsn_ie, ie->rsn_ie_len);
405 		} else if (*pos == WLAN_EID_MOBILITY_DOMAIN) {
406 			ie->mdie = pos;
407 			ie->mdie_len = pos[1] + 2;
408 			wpa_hexdump(MSG_DEBUG, "WPA: MDIE in EAPOL-Key",
409 				    ie->mdie, ie->mdie_len);
410 		} else if (*pos == WLAN_EID_FAST_BSS_TRANSITION) {
411 			ie->ftie = pos;
412 			ie->ftie_len = pos[1] + 2;
413 			wpa_hexdump(MSG_DEBUG, "WPA: FTIE in EAPOL-Key",
414 				    ie->ftie, ie->ftie_len);
415 		} else if (*pos == WLAN_EID_TIMEOUT_INTERVAL && pos[1] >= 5) {
416 			if (pos[2] == WLAN_TIMEOUT_REASSOC_DEADLINE) {
417 				ie->reassoc_deadline = pos;
418 				wpa_hexdump(MSG_DEBUG, "WPA: Reassoc Deadline "
419 					    "in EAPOL-Key",
420 					    ie->reassoc_deadline, pos[1] + 2);
421 			} else if (pos[2] == WLAN_TIMEOUT_KEY_LIFETIME) {
422 				ie->key_lifetime = pos;
423 				wpa_hexdump(MSG_DEBUG, "WPA: KeyLifetime "
424 					    "in EAPOL-Key",
425 					    ie->key_lifetime, pos[1] + 2);
426 			} else {
427 				wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized "
428 					    "EAPOL-Key Key Data IE",
429 					    pos, 2 + pos[1]);
430 			}
431 		} else if (*pos == WLAN_EID_LINK_ID) {
432 			if (pos[1] >= 18) {
433 				ie->lnkid = pos;
434 				ie->lnkid_len = pos[1] + 2;
435 			}
436 		} else if (*pos == WLAN_EID_EXT_CAPAB) {
437 			ie->ext_capab = pos;
438 			ie->ext_capab_len = pos[1] + 2;
439 		} else if (*pos == WLAN_EID_SUPP_RATES) {
440 			ie->supp_rates = pos;
441 			ie->supp_rates_len = pos[1] + 2;
442 		} else if (*pos == WLAN_EID_EXT_SUPP_RATES) {
443 			ie->ext_supp_rates = pos;
444 			ie->ext_supp_rates_len = pos[1] + 2;
445 		} else if (*pos == WLAN_EID_HT_CAP) {
446 			ie->ht_capabilities = pos + 2;
447 			ie->ht_capabilities_len = pos[1];
448 		} else if (*pos == WLAN_EID_VHT_AID) {
449 			if (pos[1] >= 2)
450 				ie->aid = WPA_GET_LE16(pos + 2);
451 		} else if (*pos == WLAN_EID_VHT_CAP) {
452 			ie->vht_capabilities = pos + 2;
453 			ie->vht_capabilities_len = pos[1];
454 		} else if (*pos == WLAN_EID_QOS && pos[1] >= 1) {
455 			ie->qosinfo = pos[2];
456 		} else if (*pos == WLAN_EID_SUPPORTED_CHANNELS) {
457 			ie->supp_channels = pos + 2;
458 			ie->supp_channels_len = pos[1];
459 		} else if (*pos == WLAN_EID_SUPPORTED_OPERATING_CLASSES) {
460 			ie->supp_oper_classes = pos + 2;
461 			ie->supp_oper_classes_len = pos[1];
462 		} else if (*pos == WLAN_EID_VENDOR_SPECIFIC) {
463 			ret = wpa_parse_generic(pos, end, ie);
464 			if (ret < 0)
465 				break;
466 			if (ret > 0) {
467 				ret = 0;
468 				break;
469 			}
470 		} else {
471 			wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized EAPOL-Key "
472 				    "Key Data IE", pos, 2 + pos[1]);
473 		}
474 	}
475 
476 	return ret;
477 }
478