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
  45         if (wpa_ie_len < sizeof(*hdr) + WPA_SELECTOR_LEN +
  46             2 + WPA_SELECTOR_LEN + 2 + WPA_SELECTOR_LEN)
  47                 return -1;
  48
  49         hdr = (struct wpa_ie_hdr *) wpa_ie;
  50         hdr->elem_id = WLAN_EID_VENDOR_SPECIFIC;
  51         RSN_SELECTOR_PUT(hdr->oui, WPA_OUI_TYPE);
  52         WPA_PUT_LE16(hdr->version, WPA_VERSION);
  53         pos = (u8 *) (hdr + 1);
  54
  55         if (group_cipher == WPA_CIPHER_CCMP) {
  56                 RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_CCMP);
  57         } else if (group_cipher == WPA_CIPHER_TKIP) {
  58                 RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_TKIP);
  59         } else if (group_cipher == WPA_CIPHER_WEP104) {
  60                 RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_WEP104);
  61         } else if (group_cipher == WPA_CIPHER_WEP40) {
  62                 RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_WEP40);
  63         } else {
  64                 wpa_printf(MSG_WARNING, "Invalid group cipher (%d).",
  65                            group_cipher);
  66                 return -1;
  67         }
  68         pos += WPA_SELECTOR_LEN;
  69
  70         *pos++ = 1;
  71         *pos++ = 0;
  72         if (pairwise_cipher == WPA_CIPHER_CCMP) {
  73                 RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_CCMP);
  74         } else if (pairwise_cipher == WPA_CIPHER_TKIP) {
  75                 RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_TKIP);
  76         } else if (pairwise_cipher == WPA_CIPHER_NONE) {
  77                 RSN_SELECTOR_PUT(pos, WPA_CIPHER_SUITE_NONE);
  78         } else {
  79                 wpa_printf(MSG_WARNING, "Invalid pairwise cipher (%d).",
  80                            pairwise_cipher);
  81                 return -1;
  82         }
  83         pos += WPA_SELECTOR_LEN;
  84
  85         *pos++ = 1;
  86         *pos++ = 0;
  87         if (key_mgmt == WPA_KEY_MGMT_IEEE8021X) {
  88                 RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_UNSPEC_802_1X);
  89         } else if (key_mgmt == WPA_KEY_MGMT_PSK) {
  90                 RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_PSK_OVER_802_1X);
  91         } else if (key_mgmt == WPA_KEY_MGMT_WPA_NONE) {
  92                 RSN_SELECTOR_PUT(pos, WPA_AUTH_KEY_MGMT_NONE);
  93         } else {
  94                 wpa_printf(MSG_WARNING, "Invalid key management type (%d).",
  95                            key_mgmt);
  96                 return -1;
  97         }
  98         pos += WPA_SELECTOR_LEN;
  99
 100         /* WPA Capabilities; use defaults, so no need to include it */
 101
 102         hdr->len = (pos - wpa_ie) - 2;
 103
 104         WPA_ASSERT((size_t) (pos - wpa_ie) <= wpa_ie_len);
 105
 106         return pos - wpa_ie;
 107 }
 108
 109
 110 static int wpa_gen_wpa_ie_rsn(u8 *rsn_ie, size_t rsn_ie_len,
 111                               int pairwise_cipher, int group_cipher,
 112                               int key_mgmt, int mgmt_group_cipher,
 113                               struct wpa_sm *sm)
 114 {
 115 #ifndef CONFIG_NO_WPA2
 116         u8 *pos;
 117         struct rsn_ie_hdr *hdr;
 118         u16 capab;
 119
 120         if (rsn_ie_len < sizeof(*hdr) + RSN_SELECTOR_LEN +
 121             2 + RSN_SELECTOR_LEN + 2 + RSN_SELECTOR_LEN + 2 +
 122             (sm->cur_pmksa ? 2 + PMKID_LEN : 0)) {
 123                 wpa_printf(MSG_DEBUG, "RSN: Too short IE buffer (%lu bytes)",
 124                            (unsigned long) rsn_ie_len);
 125                 return -1;
 126         }
 127
 128         hdr = (struct rsn_ie_hdr *) rsn_ie;
 129         hdr->elem_id = WLAN_EID_RSN;
 130         WPA_PUT_LE16(hdr->version, RSN_VERSION);
 131         pos = (u8 *) (hdr + 1);
 132
 133         if (group_cipher == WPA_CIPHER_CCMP) {
 134                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
 135         } else if (group_cipher == WPA_CIPHER_GCMP) {
 136                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_GCMP);
 137         } else if (group_cipher == WPA_CIPHER_TKIP) {
 138                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_TKIP);
 139         } else if (group_cipher == WPA_CIPHER_WEP104) {
 140                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_WEP104);
 141         } else if (group_cipher == WPA_CIPHER_WEP40) {
 142                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_WEP40);
 143         } else {
 144                 wpa_printf(MSG_WARNING, "Invalid group cipher (%d).",
 145                            group_cipher);
 146                 return -1;
 147         }
 148         pos += RSN_SELECTOR_LEN;
 149
 150         *pos++ = 1;
 151         *pos++ = 0;
 152         if (pairwise_cipher == WPA_CIPHER_CCMP) {
 153                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
 154         } else if (pairwise_cipher == WPA_CIPHER_GCMP) {
 155                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_GCMP);
 156         } else if (pairwise_cipher == WPA_CIPHER_TKIP) {
 157                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_TKIP);
 158         } else if (pairwise_cipher == WPA_CIPHER_NONE) {
 159                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_NONE);
 160         } else {
 161                 wpa_printf(MSG_WARNING, "Invalid pairwise cipher (%d).",
 162                            pairwise_cipher);
 163                 return -1;
 164         }
 165         pos += RSN_SELECTOR_LEN;
 166
 167         *pos++ = 1;
 168         *pos++ = 0;
 169         if (key_mgmt == WPA_KEY_MGMT_IEEE8021X) {
 170                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_UNSPEC_802_1X);
 171         } else if (key_mgmt == WPA_KEY_MGMT_PSK) {
 172                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_OVER_802_1X);
 173 #ifdef CONFIG_IEEE80211R
 174         } else if (key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X) {
 175                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
 176         } else if (key_mgmt == WPA_KEY_MGMT_FT_PSK) {
 177                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
 178 #endif /* CONFIG_IEEE80211R */
 179 #ifdef CONFIG_IEEE80211W
 180         } else if (key_mgmt == WPA_KEY_MGMT_IEEE8021X_SHA256) {
 181                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_802_1X_SHA256);
 182         } else if (key_mgmt == WPA_KEY_MGMT_PSK_SHA256) {
 183                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_PSK_SHA256);
 184 #endif /* CONFIG_IEEE80211W */
 185         } else {
 186                 wpa_printf(MSG_WARNING, "Invalid key management type (%d).",
 187                            key_mgmt);
 188                 return -1;
 189         }
 190         pos += RSN_SELECTOR_LEN;
 191
 192         /* RSN Capabilities */
 193         capab = 0;
 194 #ifdef CONFIG_IEEE80211W
 195         if (sm->mfp)
 196                 capab |= WPA_CAPABILITY_MFPC;
 197         if (sm->mfp == 2)
 198                 capab |= WPA_CAPABILITY_MFPR;
 199 #endif /* CONFIG_IEEE80211W */
 200         WPA_PUT_LE16(pos, capab);
 201         pos += 2;
 202
 203         if (sm->cur_pmksa) {
 204                 /* PMKID Count (2 octets, little endian) */
 205                 *pos++ = 1;
 206                 *pos++ = 0;
 207                 /* PMKID */
 208                 os_memcpy(pos, sm->cur_pmksa->pmkid, PMKID_LEN);
 209                 pos += PMKID_LEN;
 210         }
 211
 212 #ifdef CONFIG_IEEE80211W
 213         if (mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
 214                 if (!sm->cur_pmksa) {
 215                         /* PMKID Count */
 216                         WPA_PUT_LE16(pos, 0);
 217                         pos += 2;
 218                 }
 219
 220                 /* Management Group Cipher Suite */
 221                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
 222                 pos += RSN_SELECTOR_LEN;
 223         }
 224 #endif /* CONFIG_IEEE80211W */
 225
 226         hdr->len = (pos - rsn_ie) - 2;
 227
 228         WPA_ASSERT((size_t) (pos - rsn_ie) <= rsn_ie_len);
 229
 230         return pos - rsn_ie;
 231 #else /* CONFIG_NO_WPA2 */
 232         return -1;
 233 #endif /* CONFIG_NO_WPA2 */
 234 }
 235
 236
 237 /**
 238  * wpa_gen_wpa_ie - Generate WPA/RSN IE based on current security policy
 239  * @sm: Pointer to WPA state machine data from wpa_sm_init()
 240  * @wpa_ie: Pointer to memory area for the generated WPA/RSN IE
 241  * @wpa_ie_len: Maximum length of the generated WPA/RSN IE
 242  * Returns: Length of the generated WPA/RSN IE or -1 on failure
 243  */
 244 int wpa_gen_wpa_ie(struct wpa_sm *sm, u8 *wpa_ie, size_t wpa_ie_len)
 245 {
 246         if (sm->proto == WPA_PROTO_RSN)
 247                 return wpa_gen_wpa_ie_rsn(wpa_ie, wpa_ie_len,
 248                                           sm->pairwise_cipher,
 249                                           sm->group_cipher,
 250                                           sm->key_mgmt, sm->mgmt_group_cipher,
 251                                           sm);
 252         else
 253                 return wpa_gen_wpa_ie_wpa(wpa_ie, wpa_ie_len,
 254                                           sm->pairwise_cipher,
 255                                           sm->group_cipher,
 256                                           sm->key_mgmt);
 257 }
 258
 259
 260 /**
 261  * wpa_parse_generic - Parse EAPOL-Key Key Data Generic IEs
 262  * @pos: Pointer to the IE header
 263  * @end: Pointer to the end of the Key Data buffer
 264  * @ie: Pointer to parsed IE data
 265  * Returns: 0 on success, 1 if end mark is found, -1 on failure
 266  */
 267 static int wpa_parse_generic(const u8 *pos, const u8 *end,
 268                              struct wpa_eapol_ie_parse *ie)
 269 {
 270         if (pos[1] == 0)
 271                 return 1;
 272
 273         if (pos[1] >= 6 &&
 274             RSN_SELECTOR_GET(pos + 2) == WPA_OUI_TYPE &&
 275             pos[2 + WPA_SELECTOR_LEN] == 1 &&
 276             pos[2 + WPA_SELECTOR_LEN + 1] == 0) {
 277                 ie->wpa_ie = pos;
 278                 ie->wpa_ie_len = pos[1] + 2;
 279                 wpa_hexdump(MSG_DEBUG, "WPA: WPA IE in EAPOL-Key",
 280                             ie->wpa_ie, ie->wpa_ie_len);
 281                 return 0;
 282         }
 283
 284         if (pos + 1 + RSN_SELECTOR_LEN < end &&
 285             pos[1] >= RSN_SELECTOR_LEN + PMKID_LEN &&
 286             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_PMKID) {
 287                 ie->pmkid = pos + 2 + RSN_SELECTOR_LEN;
 288                 wpa_hexdump(MSG_DEBUG, "WPA: PMKID in EAPOL-Key",
 289                             pos, pos[1] + 2);
 290                 return 0;
 291         }
 292
 293         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 294             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_GROUPKEY) {
 295                 ie->gtk = pos + 2 + RSN_SELECTOR_LEN;
 296                 ie->gtk_len = pos[1] - RSN_SELECTOR_LEN;
 297                 wpa_hexdump_key(MSG_DEBUG, "WPA: GTK in EAPOL-Key",
 298                                 pos, pos[1] + 2);
 299                 return 0;
 300         }
 301
 302         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 303             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_MAC_ADDR) {
 304                 ie->mac_addr = pos + 2 + RSN_SELECTOR_LEN;
 305                 ie->mac_addr_len = pos[1] - RSN_SELECTOR_LEN;
 306                 wpa_hexdump(MSG_DEBUG, "WPA: MAC Address in EAPOL-Key",
 307                             pos, pos[1] + 2);
 308                 return 0;
 309         }
 310
 311 #ifdef CONFIG_PEERKEY
 312         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 313             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_SMK) {
 314                 ie->smk = pos + 2 + RSN_SELECTOR_LEN;
 315                 ie->smk_len = pos[1] - RSN_SELECTOR_LEN;
 316                 wpa_hexdump_key(MSG_DEBUG, "WPA: SMK 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_NONCE) {
 323                 ie->nonce = pos + 2 + RSN_SELECTOR_LEN;
 324                 ie->nonce_len = pos[1] - RSN_SELECTOR_LEN;
 325                 wpa_hexdump(MSG_DEBUG, "WPA: Nonce in EAPOL-Key",
 326                             pos, pos[1] + 2);
 327                 return 0;
 328         }
 329
 330         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 331             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_LIFETIME) {
 332                 ie->lifetime = pos + 2 + RSN_SELECTOR_LEN;
 333                 ie->lifetime_len = pos[1] - RSN_SELECTOR_LEN;
 334                 wpa_hexdump(MSG_DEBUG, "WPA: Lifetime in EAPOL-Key",
 335                             pos, pos[1] + 2);
 336                 return 0;
 337         }
 338
 339         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 340             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_ERROR) {
 341                 ie->error = pos + 2 + RSN_SELECTOR_LEN;
 342                 ie->error_len = pos[1] - RSN_SELECTOR_LEN;
 343                 wpa_hexdump(MSG_DEBUG, "WPA: Error in EAPOL-Key",
 344                             pos, pos[1] + 2);
 345                 return 0;
 346         }
 347 #endif /* CONFIG_PEERKEY */
 348
 349 #ifdef CONFIG_IEEE80211W
 350         if (pos[1] > RSN_SELECTOR_LEN + 2 &&
 351             RSN_SELECTOR_GET(pos + 2) == RSN_KEY_DATA_IGTK) {
 352                 ie->igtk = pos + 2 + RSN_SELECTOR_LEN;
 353                 ie->igtk_len = pos[1] - RSN_SELECTOR_LEN;
 354                 wpa_hexdump_key(MSG_DEBUG, "WPA: IGTK in EAPOL-Key",
 355                                 pos, pos[1] + 2);
 356                 return 0;
 357         }
 358 #endif /* CONFIG_IEEE80211W */
 359
 360         return 0;
 361 }
 362
 363
 364 /**
 365  * wpa_supplicant_parse_ies - Parse EAPOL-Key Key Data IEs
 366  * @buf: Pointer to the Key Data buffer
 367  * @len: Key Data Length
 368  * @ie: Pointer to parsed IE data
 369  * Returns: 0 on success, -1 on failure
 370  */
 371 int wpa_supplicant_parse_ies(const u8 *buf, size_t len,
 372                              struct wpa_eapol_ie_parse *ie)
 373 {
 374         const u8 *pos, *end;
 375         int ret = 0;
 376
 377         os_memset(ie, 0, sizeof(*ie));
 378         for (pos = buf, end = pos + len; pos + 1 < end; pos += 2 + pos[1]) {
 379                 if (pos[0] == 0xdd &&
 380                     ((pos == buf + len - 1) || pos[1] == 0)) {
 381                         /* Ignore padding */
 382                         break;
 383                 }
 384                 if (pos + 2 + pos[1] > end) {
 385                         wpa_printf(MSG_DEBUG, "WPA: EAPOL-Key Key Data "
 386                                    "underflow (ie=%d len=%d pos=%d)",
 387                                    pos[0], pos[1], (int) (pos - buf));
 388                         wpa_hexdump_key(MSG_DEBUG, "WPA: Key Data",
 389                                         buf, len);
 390                         ret = -1;
 391                         break;
 392                 }
 393                 if (*pos == WLAN_EID_RSN) {
 394                         ie->rsn_ie = pos;
 395                         ie->rsn_ie_len = pos[1] + 2;
 396                         wpa_hexdump(MSG_DEBUG, "WPA: RSN IE in EAPOL-Key",
 397                                     ie->rsn_ie, ie->rsn_ie_len);
 398                 } else if (*pos == WLAN_EID_MOBILITY_DOMAIN) {
 399                         ie->mdie = pos;
 400                         ie->mdie_len = pos[1] + 2;
 401                         wpa_hexdump(MSG_DEBUG, "WPA: MDIE in EAPOL-Key",
 402                                     ie->mdie, ie->mdie_len);
 403                 } else if (*pos == WLAN_EID_FAST_BSS_TRANSITION) {
 404                         ie->ftie = pos;
 405                         ie->ftie_len = pos[1] + 2;
 406                         wpa_hexdump(MSG_DEBUG, "WPA: FTIE in EAPOL-Key",
 407                                     ie->ftie, ie->ftie_len);
 408                 } else if (*pos == WLAN_EID_TIMEOUT_INTERVAL && pos[1] >= 5) {
 409                         if (pos[2] == WLAN_TIMEOUT_REASSOC_DEADLINE) {
 410                                 ie->reassoc_deadline = pos;
 411                                 wpa_hexdump(MSG_DEBUG, "WPA: Reassoc Deadline "
 412                                             "in EAPOL-Key",
 413                                             ie->reassoc_deadline, pos[1] + 2);
 414                         } else if (pos[2] == WLAN_TIMEOUT_KEY_LIFETIME) {
 415                                 ie->key_lifetime = pos;
 416                                 wpa_hexdump(MSG_DEBUG, "WPA: KeyLifetime "
 417                                             "in EAPOL-Key",
 418                                             ie->key_lifetime, pos[1] + 2);
 419                         } else {
 420                                 wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized "
 421                                             "EAPOL-Key Key Data IE",
 422                                             pos, 2 + pos[1]);
 423                         }
 424                 } else if (*pos == WLAN_EID_LINK_ID) {
 425                         if (pos[1] >= 18) {
 426                                 ie->lnkid = pos;
 427                                 ie->lnkid_len = pos[1] + 2;
 428                         }
 429                 } else if (*pos == WLAN_EID_EXT_CAPAB) {
 430                         ie->ext_capab = pos;
 431                         ie->ext_capab_len = pos[1] + 2;
 432                 } else if (*pos == WLAN_EID_SUPP_RATES) {
 433                         ie->supp_rates = pos;
 434                         ie->supp_rates_len = pos[1] + 2;
 435                 } else if (*pos == WLAN_EID_EXT_SUPP_RATES) {
 436                         ie->ext_supp_rates = pos;
 437                         ie->ext_supp_rates_len = pos[1] + 2;
 438                 } else if (*pos == WLAN_EID_VENDOR_SPECIFIC) {
 439                         ret = wpa_parse_generic(pos, end, ie);
 440                         if (ret < 0)
 441                                 break;
 442                         if (ret > 0) {
 443                                 ret = 0;
 444                                 break;
 445                         }
 446                 } else {
 447                         wpa_hexdump(MSG_DEBUG, "WPA: Unrecognized EAPOL-Key "
 448                                     "Key Data IE", pos, 2 + pos[1]);
 449                 }
 450         }
 451
 452         return ret;
 453 }