contrib/wpa/src/rsn_supp/wpa_ie.c

   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 #ifndef CONFIG_NO_WPA2
 111         u8 *pos;
 112         struct rsn_ie_hdr *hdr;
 113         u16 capab;
 114         u32 suite;
 115
 116         if (rsn_ie_len < sizeof(*hdr) + RSN_SELECTOR_LEN +
 117             2 + RSN_SELECTOR_LEN + 2 + RSN_SELECTOR_LEN + 2 +
 118             (sm->cur_pmksa ? 2 + PMKID_LEN : 0)) {
 119                 wpa_printf(MSG_DEBUG, "RSN: Too short IE buffer (%lu bytes)",
 120                            (unsigned long) rsn_ie_len);
 121                 return -1;
 122         }
 123
 124         hdr = (struct rsn_ie_hdr *) rsn_ie;
 125         hdr->elem_id = WLAN_EID_RSN;
 126         WPA_PUT_LE16(hdr->version, RSN_VERSION);
 127         pos = (u8 *) (hdr + 1);
 128
 129         suite = wpa_cipher_to_suite(WPA_PROTO_RSN, group_cipher);
 130         if (suite == 0) {
 131                 wpa_printf(MSG_WARNING, "Invalid group cipher (%d).",
 132                            group_cipher);
 133                 return -1;
 134         }
 135         RSN_SELECTOR_PUT(pos, suite);
 136         pos += RSN_SELECTOR_LEN;
 137
 138         *pos++ = 1;
 139         *pos++ = 0;
 140         suite = wpa_cipher_to_suite(WPA_PROTO_RSN, pairwise_cipher);
 141         if (suite == 0 ||
 142             (!wpa_cipher_valid_pairwise(pairwise_cipher) &&
 143              pairwise_cipher != WPA_CIPHER_NONE)) {
 144                 wpa_printf(MSG_WARNING, "Invalid pairwise cipher (%d).",
 145                            pairwise_cipher);
 146                 return -1;
 147         }
 148         RSN_SELECTOR_PUT(pos, suite);
 149         pos += RSN_SELECTOR_LEN;
 150
 151         *pos++ = 1;
 152         *pos++ = 0;
 153         if (key_mgmt == WPA_KEY_MGMT_IEEE8021X) {
 154                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_UNSPEC_802_1X);
 155         } else if (key_mgmt == WPA_KEY_MGMT_PSK) {
 156                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_OVER_802_1X);
 157         } else if (key_mgmt == WPA_KEY_MGMT_CCKM) {
 158                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_CCKM);
 159 #ifdef CONFIG_IEEE80211R
 160         } else if (key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X) {
 161                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
 162         } else if (key_mgmt == WPA_KEY_MGMT_FT_PSK) {
 163                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
 164 #endif /* CONFIG_IEEE80211R */
 165 #ifdef CONFIG_IEEE80211W
 166         } else if (key_mgmt == WPA_KEY_MGMT_IEEE8021X_SHA256) {
 167                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_802_1X_SHA256);
 168         } else if (key_mgmt == WPA_KEY_MGMT_PSK_SHA256) {
 169                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_SHA256);
 170 #endif /* CONFIG_IEEE80211W */
 171 #ifdef CONFIG_SAE
 172         } else if (key_mgmt == WPA_KEY_MGMT_SAE) {
 173                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_SAE);
 174         } else if (key_mgmt == WPA_KEY_MGMT_FT_SAE) {
 175                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_SAE);
 176 #endif /* CONFIG_SAE */
 177         } else {
 178                 wpa_printf(MSG_WARNING, "Invalid key management type (%d).",
 179                            key_mgmt);
 180                 return -1;
 181         }
 182         pos += RSN_SELECTOR_LEN;
 183
 184         /* RSN Capabilities */
 185         capab = 0;
 186 #ifdef CONFIG_IEEE80211W
 187         if (sm->mfp)
 188                 capab |= WPA_CAPABILITY_MFPC;
 189         if (sm->mfp == 2)
 190                 capab |= WPA_CAPABILITY_MFPR;
 191 #endif /* CONFIG_IEEE80211W */
 192         WPA_PUT_LE16(pos, capab);
 193         pos += 2;
 194
 195         if (sm->cur_pmksa) {
 196                 /* PMKID Count (2 octets, little endian) */
 197                 *pos++ = 1;
 198                 *pos++ = 0;
 199                 /* PMKID */
 200                 os_memcpy(pos, sm->cur_pmksa->pmkid, PMKID_LEN);
 201                 pos += PMKID_LEN;
 202         }
 203
 204 #ifdef CONFIG_IEEE80211W
 205         if (mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
 206                 if (!sm->cur_pmksa) {
 207                         /* PMKID Count */
 208                         WPA_PUT_LE16(pos, 0);
 209                         pos += 2;
 210                 }
 211
 212                 /* Management Group Cipher Suite */
 213                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
 214                 pos += RSN_SELECTOR_LEN;
 215         }
 216 #endif /* CONFIG_IEEE80211W */
 217
 218         hdr->len = (pos - rsn_ie) - 2;
 219
 220         WPA_ASSERT((size_t) (pos - rsn_ie) <= rsn_ie_len);
 221
 222         return pos - rsn_ie;
 223 #else /* CONFIG_NO_WPA2 */
 224         return -1;
 225 #endif /* CONFIG_NO_WPA2 */
 226 }
 227
 228
 229 /**
 230  * wpa_gen_wpa_ie - Generate WPA/RSN IE based on current security policy
 231  * @sm: Pointer to WPA state machine data from wpa_sm_init()
 232  * @wpa_ie: Pointer to memory area for the generated WPA/RSN IE
 233  * @wpa_ie_len: Maximum length of the generated WPA/RSN IE
 234  * Returns: Length of the generated WPA/RSN IE or -1 on failure
 235  */
 236 int wpa_gen_wpa_ie(struct wpa_sm *sm, u8 *wpa_ie, size_t wpa_ie_len)
 237 {
 238         if (sm->proto == WPA_PROTO_RSN)
 239                 return wpa_gen_wpa_ie_rsn(wpa_ie, wpa_ie_len,
 240                                           sm->pairwise_cipher,
 241                                           sm->group_cipher,
 242                                           sm->key_mgmt, sm->mgmt_group_cipher,
 243                                           sm);
 244         else
 245                 return wpa_gen_wpa_ie_wpa(wpa_ie, wpa_ie_len,
 246                                           sm->pairwise_cipher,
 247                                           sm->group_cipher,
 248                                           sm->key_mgmt);
 249 }
 250
 251
 252 /**
 253  * wpa_parse_generic - Parse EAPOL-Key Key Data Generic IEs
 254  * @pos: Pointer to the IE header
 255  * @end: Pointer to the end of the Key Data buffer
 256  * @ie: Pointer to parsed IE data
 257  * Returns: 0 on success, 1 if end mark is found, -1 on failure
 258  */
 259 static int wpa_parse_generic(const u8 *pos, const u8 *end,
 260                              struct wpa_eapol_ie_parse *ie)
 261 {
 262         if (pos[1] == 0)
 263                 return 1;
 264
 265         if (pos[1] >= 6 &&
 266             RSN_SELECTOR_GET(pos + 2) == WPA_OUI_TYPE &&
 267             pos[2 + WPA_SELECTOR_LEN] == 1 &&
 268             pos[2 + WPA_SELECTOR_LEN + 1] == 0) {
 269                 ie->wpa_ie = pos;
 270                 ie->wpa_ie_len = pos[1] + 2;
 271                 wpa_hexdump(MSG_DEBUG, "WPA: WPA IE in EAPOL-Key",
 272                             ie->wpa_ie, ie->wpa_ie_len);
 273                 return 0;
 274         }
 275
 276         if (pos + 1 + RSN_SELECTOR_LEN < end &&
 277             pos[1] >= RSN_SELECTOR_LEN + PMKID_LEN &&
 278             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_PMKID) {
 279                 ie->pmkid = pos + 2 + RSN_SELECTOR_LEN;
 280                 wpa_hexdump(MSG_DEBUG, "WPA: PMKID in EAPOL-Key",
 281                             pos, pos[1] + 2);
 282                 return 0;
 283         }
 284
 285         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 286             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_GROUPKEY) {
 287                 ie->gtk = pos + 2 + RSN_SELECTOR_LEN;
 288                 ie->gtk_len = pos[1] - RSN_SELECTOR_LEN;
 289                 wpa_hexdump_key(MSG_DEBUG, "WPA: GTK in EAPOL-Key",
 290                                 pos, pos[1] + 2);
 291                 return 0;
 292         }
 293
 294         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 295             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_MAC_ADDR) {
 296                 ie->mac_addr = pos + 2 + RSN_SELECTOR_LEN;
 297                 ie->mac_addr_len = pos[1] - RSN_SELECTOR_LEN;
 298                 wpa_hexdump(MSG_DEBUG, "WPA: MAC Address in EAPOL-Key",
 299                             pos, pos[1] + 2);
 300                 return 0;
 301         }
 302
 303 #ifdef CONFIG_PEERKEY
 304         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 305             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_SMK) {
 306                 ie->smk = pos + 2 + RSN_SELECTOR_LEN;
 307                 ie->smk_len = pos[1] - RSN_SELECTOR_LEN;
 308                 wpa_hexdump_key(MSG_DEBUG, "WPA: SMK in EAPOL-Key",
 309                                 pos, pos[1] + 2);
 310                 return 0;
 311         }
 312
 313         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 314             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_NONCE) {
 315                 ie->nonce = pos + 2 + RSN_SELECTOR_LEN;
 316                 ie->nonce_len = pos[1] - RSN_SELECTOR_LEN;
 317                 wpa_hexdump(MSG_DEBUG, "WPA: Nonce in EAPOL-Key",
 318                             pos, pos[1] + 2);
 319                 return 0;
 320         }
 321
 322         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 323             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_LIFETIME) {
 324                 ie->lifetime = pos + 2 + RSN_SELECTOR_LEN;
 325                 ie->lifetime_len = pos[1] - RSN_SELECTOR_LEN;
 326                 wpa_hexdump(MSG_DEBUG, "WPA: Lifetime in EAPOL-Key",
 327                             pos, pos[1] + 2);
 328                 return 0;
 329         }
 330
 331         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 332             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_ERROR) {
 333                 ie->error = pos + 2 + RSN_SELECTOR_LEN;
 334                 ie->error_len = pos[1] - RSN_SELECTOR_LEN;
 335                 wpa_hexdump(MSG_DEBUG, "WPA: Error in EAPOL-Key",
 336                             pos, pos[1] + 2);
 337                 return 0;
 338         }
 339 #endif /* CONFIG_PEERKEY */
 340
 341 #ifdef CONFIG_IEEE80211W
 342         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 343             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_IGTK) {
 344                 ie->igtk = pos + 2 + RSN_SELECTOR_LEN;
 345                 ie->igtk_len = pos[1] - RSN_SELECTOR_LEN;
 346                 wpa_hexdump_key(MSG_DEBUG, "WPA: IGTK in EAPOL-Key",
 347                                 pos, pos[1] + 2);
 348                 return 0;
 349         }
 350 #endif /* CONFIG_IEEE80211W */
 351
 352         return 0;
 353 }
 354
 355
 356 /**
 357  * wpa_supplicant_parse_ies - Parse EAPOL-Key Key Data IEs
 358  * @buf: Pointer to the Key Data buffer
 359  * @len: Key Data Length
 360  * @ie: Pointer to parsed IE data
 361  * Returns: 0 on success, -1 on failure
 362  */
 363 int wpa_supplicant_parse_ies(const u8 *buf, size_t len,
 364                              struct wpa_eapol_ie_parse *ie)
 365 {
 366         const u8 *pos, *end;
 367         int ret = 0;
 368
 369         os_memset(ie, 0, sizeof(*ie));
 370         for (pos = buf, end = pos + len; pos + 1 < end; pos += 2 + pos[1]) {
 371                 if (pos[0] == 0xdd &&
 372                     ((pos == buf + len - 1) || pos[1] == 0)) {
 373                         /* Ignore padding */
 374                         break;
 375                 }
 376                 if (pos + 2 + pos[1] > end) {
 377                         wpa_printf(MSG_DEBUG, "WPA: EAPOL-Key Key Data "
 378                                    "underflow (ie=%d len=%d pos=%d)",
 379                                    pos[0], pos[1], (int) (pos - buf));
 380                         wpa_hexdump_key(MSG_DEBUG, "WPA: Key Data",
 381                                         buf, len);
 382                         ret = -1;
 383                         break;
 384                 }
 385                 if (*pos == WLAN_EID_RSN) {
 386                         ie->rsn_ie = pos;
 387                         ie->rsn_ie_len = pos[1] + 2;
 388                         wpa_hexdump(MSG_DEBUG, "WPA: RSN IE in EAPOL-Key",
 389                                     ie->rsn_ie, ie->rsn_ie_len);
 390                 } else if (*pos == WLAN_EID_MOBILITY_DOMAIN) {
 391                         ie->mdie = pos;
 392                         ie->mdie_len = pos[1] + 2;
 393                         wpa_hexdump(MSG_DEBUG, "WPA: MDIE in EAPOL-Key",
 394                                     ie->mdie, ie->mdie_len);
 395                 } else if (*pos == WLAN_EID_FAST_BSS_TRANSITION) {
 396                         ie->ftie = pos;
 397                         ie->ftie_len = pos[1] + 2;
 398                         wpa_hexdump(MSG_DEBUG, "WPA: FTIE in EAPOL-Key",
 399                                     ie->ftie, ie->ftie_len);
 400                 } else if (*pos == WLAN_EID_TIMEOUT_INTERVAL && pos[1] >= 5) {
 401                         if (pos[2] == WLAN_TIMEOUT_REASSOC_DEADLINE) {
 402                                 ie->reassoc_deadline = pos;
 403                                 wpa_hexdump(MSG_DEBUG, "WPA: Reassoc Deadline "
 404                                             "in EAPOL-Key",
 405                                             ie->reassoc_deadline, pos[1] + 2);
 406                         } else if (pos[2] == WLAN_TIMEOUT_KEY_LIFETIME) {
 407                                 ie->key_lifetime = pos;
 408                                 wpa_hexdump(MSG_DEBUG, "WPA: KeyLifetime "
 409                                             "in EAPOL-Key",
 410                                             ie->key_lifetime, pos[1] + 2);
 411                         } else {
 412                                 wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized "
 413                                             "EAPOL-Key Key Data IE",
 414                                             pos, 2 + pos[1]);
 415                         }
 416                 } else if (*pos == WLAN_EID_LINK_ID) {
 417                         if (pos[1] >= 18) {
 418                                 ie->lnkid = pos;
 419                                 ie->lnkid_len = pos[1] + 2;
 420                         }
 421                 } else if (*pos == WLAN_EID_EXT_CAPAB) {
 422                         ie->ext_capab = pos;
 423                         ie->ext_capab_len = pos[1] + 2;
 424                 } else if (*pos == WLAN_EID_SUPP_RATES) {
 425                         ie->supp_rates = pos;
 426                         ie->supp_rates_len = pos[1] + 2;
 427                 } else if (*pos == WLAN_EID_EXT_SUPP_RATES) {
 428                         ie->ext_supp_rates = pos;
 429                         ie->ext_supp_rates_len = pos[1] + 2;
 430                 } else if (*pos == WLAN_EID_VENDOR_SPECIFIC) {
 431                         ret = wpa_parse_generic(pos, end, ie);
 432                         if (ret < 0)
 433                                 break;
 434                         if (ret > 0) {
 435                                 ret = 0;
 436                                 break;
 437                         }
 438                 } else {
 439                         wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized EAPOL-Key "
 440                                     "Key Data IE", pos, 2 + pos[1]);
 441                 }
 442         }
 443
 444         return ret;
 445 }