wpa_ft.c
Go to the documentation of this file.
00001 /*
00002  * WPA Supplicant - IEEE 802.11r - Fast BSS Transition
00003  * Copyright (c) 2006-2007, Jouni Malinen <j@w1.fi>
00004  *
00005  * This program is free software; you can redistribute it and/or modify
00006  * it under the terms of the GNU General Public License version 2 as
00007  * published by the Free Software Foundation.
00008  *
00009  * Alternatively, this software may be distributed under the terms of BSD
00010  * license.
00011  *
00012  * See README and COPYING for more details.
00013  */
00014 
00015 #include "includes.h"
00016 
00017 #include "common.h"
00018 #include "crypto/aes_wrap.h"
00019 #include "common/ieee802_11_defs.h"
00020 #include "common/ieee802_11_common.h"
00021 #include "wpa.h"
00022 #include "wpa_i.h"
00023 #include "wpa_ie.h"
00024 
00025 #ifdef CONFIG_IEEE80211R
00026 
00027 struct wpa_ft_ies {
00028         const u8 *mdie;
00029         size_t mdie_len;
00030         const u8 *ftie;
00031         size_t ftie_len;
00032         const u8 *r1kh_id;
00033         const u8 *gtk;
00034         size_t gtk_len;
00035         const u8 *r0kh_id;
00036         size_t r0kh_id_len;
00037         const u8 *rsn;
00038         size_t rsn_len;
00039         const u8 *rsn_pmkid;
00040         const u8 *tie;
00041         size_t tie_len;
00042         const u8 *igtk;
00043         size_t igtk_len;
00044         const u8 *ric;
00045         size_t ric_len;
00046 };
00047 
00048 static int wpa_ft_parse_ies(const u8 *ies, size_t ies_len,
00049                             struct wpa_ft_ies *parse);
00050 
00051 
00052 int wpa_derive_ptk_ft(struct wpa_sm *sm, const unsigned char *src_addr,
00053                       const struct wpa_eapol_key *key,
00054                       struct wpa_ptk *ptk, size_t ptk_len)
00055 {
00056         u8 ptk_name[WPA_PMK_NAME_LEN];
00057         const u8 *anonce = key->key_nonce;
00058 
00059         if (sm->xxkey_len == 0) {
00060                 wpa_printf(MSG_DEBUG, "FT: XXKey not available for key "
00061                            "derivation");
00062                 return -1;
00063         }
00064 
00065         wpa_derive_pmk_r0(sm->xxkey, sm->xxkey_len, sm->ssid,
00066                           sm->ssid_len, sm->mobility_domain,
00067                           sm->r0kh_id, sm->r0kh_id_len, sm->own_addr,
00068                           sm->pmk_r0, sm->pmk_r0_name);
00069         wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R0", sm->pmk_r0, PMK_LEN);
00070         wpa_hexdump(MSG_DEBUG, "FT: PMKR0Name",
00071                     sm->pmk_r0_name, WPA_PMK_NAME_LEN);
00072         wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
00073                           sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
00074         wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
00075         wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name", sm->pmk_r1_name,
00076                     WPA_PMK_NAME_LEN);
00077         wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, anonce, sm->own_addr,
00078                           sm->bssid, sm->pmk_r1_name,
00079                           (u8 *) ptk, ptk_len, ptk_name);
00080         wpa_hexdump_key(MSG_DEBUG, "FT: PTK", (u8 *) ptk, ptk_len);
00081         wpa_hexdump(MSG_DEBUG, "FT: PTKName", ptk_name, WPA_PMK_NAME_LEN);
00082 
00083         return 0;
00084 }
00085 
00086 
00094 int wpa_sm_set_ft_params(struct wpa_sm *sm, const u8 *ies, size_t ies_len)
00095 {
00096         struct wpa_ft_ies ft;
00097 
00098         if (sm == NULL)
00099                 return 0;
00100 
00101         if (wpa_ft_parse_ies(ies, ies_len, &ft) < 0)
00102                 return -1;
00103 
00104         if (ft.mdie && ft.mdie_len < MOBILITY_DOMAIN_ID_LEN + 1)
00105                 return -1;
00106 
00107         if (ft.mdie) {
00108                 wpa_hexdump(MSG_DEBUG, "FT: Mobility domain",
00109                             ft.mdie, MOBILITY_DOMAIN_ID_LEN);
00110                 os_memcpy(sm->mobility_domain, ft.mdie,
00111                           MOBILITY_DOMAIN_ID_LEN);
00112                 sm->mdie_ft_capab = ft.mdie[MOBILITY_DOMAIN_ID_LEN];
00113                 wpa_printf(MSG_DEBUG, "FT: Capability and Policy: 0x%02x",
00114                            sm->mdie_ft_capab);
00115         } else
00116                 os_memset(sm->mobility_domain, 0, MOBILITY_DOMAIN_ID_LEN);
00117 
00118         if (ft.r0kh_id) {
00119                 wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID",
00120                             ft.r0kh_id, ft.r0kh_id_len);
00121                 os_memcpy(sm->r0kh_id, ft.r0kh_id, ft.r0kh_id_len);
00122                 sm->r0kh_id_len = ft.r0kh_id_len;
00123         } else {
00124                 /* FIX: When should R0KH-ID be cleared? We need to keep the
00125                  * old R0KH-ID in order to be able to use this during FT. */
00126                 /*
00127                  * os_memset(sm->r0kh_id, 0, FT_R0KH_ID_LEN);
00128                  * sm->r0kh_id_len = 0;
00129                  */
00130         }
00131 
00132         if (ft.r1kh_id) {
00133                 wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID",
00134                             ft.r1kh_id, FT_R1KH_ID_LEN);
00135                 os_memcpy(sm->r1kh_id, ft.r1kh_id, FT_R1KH_ID_LEN);
00136         } else
00137                 os_memset(sm->r1kh_id, 0, FT_R1KH_ID_LEN);
00138 
00139         os_free(sm->assoc_resp_ies);
00140         sm->assoc_resp_ies = os_malloc(ft.mdie_len + 2 + ft.ftie_len + 2);
00141         if (sm->assoc_resp_ies) {
00142                 u8 *pos = sm->assoc_resp_ies;
00143                 if (ft.mdie) {
00144                         os_memcpy(pos, ft.mdie - 2, ft.mdie_len + 2);
00145                         pos += ft.mdie_len + 2;
00146                 }
00147                 if (ft.ftie) {
00148                         os_memcpy(pos, ft.ftie - 2, ft.ftie_len + 2);
00149                         pos += ft.ftie_len + 2;
00150                 }
00151                 sm->assoc_resp_ies_len = pos - sm->assoc_resp_ies;
00152                 wpa_hexdump(MSG_DEBUG, "FT: Stored MDIE and FTIE from "
00153                             "(Re)Association Response",
00154                             sm->assoc_resp_ies, sm->assoc_resp_ies_len);
00155         }
00156 
00157         return 0;
00158 }
00159 
00160 
00176 static u8 * wpa_ft_gen_req_ies(struct wpa_sm *sm, size_t *len,
00177                                const u8 *anonce, const u8 *pmk_name,
00178                                const u8 *kck, const u8 *target_ap,
00179                                const u8 *ric_ies, size_t ric_ies_len,
00180                                const u8 *ap_mdie)
00181 {
00182         size_t buf_len;
00183         u8 *buf, *pos, *ftie_len, *ftie_pos;
00184         struct rsn_mdie *mdie;
00185         struct rsn_ftie *ftie;
00186         struct rsn_ie_hdr *rsnie;
00187         u16 capab;
00188 
00189         sm->ft_completed = 0;
00190 
00191         buf_len = 2 + sizeof(struct rsn_mdie) + 2 + sizeof(struct rsn_ftie) +
00192                 2 + sm->r0kh_id_len + ric_ies_len + 100;
00193         buf = os_zalloc(buf_len);
00194         if (buf == NULL)
00195                 return NULL;
00196         pos = buf;
00197 
00198         /* RSNIE[PMKR0Name/PMKR1Name] */
00199         rsnie = (struct rsn_ie_hdr *) pos;
00200         rsnie->elem_id = WLAN_EID_RSN;
00201         WPA_PUT_LE16(rsnie->version, RSN_VERSION);
00202         pos = (u8 *) (rsnie + 1);
00203 
00204         /* Group Suite Selector */
00205         if (sm->group_cipher == WPA_CIPHER_CCMP)
00206                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
00207         else if (sm->group_cipher == WPA_CIPHER_TKIP)
00208                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_TKIP);
00209         else {
00210                 wpa_printf(MSG_WARNING, "FT: Invalid group cipher (%d)",
00211                            sm->group_cipher);
00212                 os_free(buf);
00213                 return NULL;
00214         }
00215         pos += RSN_SELECTOR_LEN;
00216 
00217         /* Pairwise Suite Count */
00218         WPA_PUT_LE16(pos, 1);
00219         pos += 2;
00220 
00221         /* Pairwise Suite List */
00222         if (sm->pairwise_cipher == WPA_CIPHER_CCMP)
00223                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_CCMP);
00224         else if (sm->pairwise_cipher == WPA_CIPHER_TKIP)
00225                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_TKIP);
00226         else {
00227                 wpa_printf(MSG_WARNING, "FT: Invalid pairwise cipher (%d)",
00228                            sm->pairwise_cipher);
00229                 os_free(buf);
00230                 return NULL;
00231         }
00232         pos += RSN_SELECTOR_LEN;
00233 
00234         /* Authenticated Key Management Suite Count */
00235         WPA_PUT_LE16(pos, 1);
00236         pos += 2;
00237 
00238         /* Authenticated Key Management Suite List */
00239         if (sm->key_mgmt == WPA_KEY_MGMT_FT_IEEE8021X)
00240                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_802_1X);
00241         else if (sm->key_mgmt == WPA_KEY_MGMT_FT_PSK)
00242                 RSN_SELECTOR_PUT(pos, RSN_AUTH_KEY_MGMT_FT_PSK);
00243         else {
00244                 wpa_printf(MSG_WARNING, "FT: Invalid key management type (%d)",
00245                            sm->key_mgmt);
00246                 os_free(buf);
00247                 return NULL;
00248         }
00249         pos += RSN_SELECTOR_LEN;
00250 
00251         /* RSN Capabilities */
00252         capab = 0;
00253 #ifdef CONFIG_IEEE80211W
00254         if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC)
00255                 capab |= WPA_CAPABILITY_MFPC;
00256 #endif /* CONFIG_IEEE80211W */
00257         WPA_PUT_LE16(pos, capab);
00258         pos += 2;
00259 
00260         /* PMKID Count */
00261         WPA_PUT_LE16(pos, 1);
00262         pos += 2;
00263 
00264         /* PMKID List [PMKR0Name/PMKR1Name] */
00265         os_memcpy(pos, pmk_name, WPA_PMK_NAME_LEN);
00266         pos += WPA_PMK_NAME_LEN;
00267 
00268 #ifdef CONFIG_IEEE80211W
00269         if (sm->mgmt_group_cipher == WPA_CIPHER_AES_128_CMAC) {
00270                 /* Management Group Cipher Suite */
00271                 RSN_SELECTOR_PUT(pos, RSN_CIPHER_SUITE_AES_128_CMAC);
00272                 pos += RSN_SELECTOR_LEN;
00273         }
00274 #endif /* CONFIG_IEEE80211W */
00275 
00276         rsnie->len = (pos - (u8 *) rsnie) - 2;
00277 
00278         /* MDIE */
00279         *pos++ = WLAN_EID_MOBILITY_DOMAIN;
00280         *pos++ = sizeof(*mdie);
00281         mdie = (struct rsn_mdie *) pos;
00282         pos += sizeof(*mdie);
00283         os_memcpy(mdie->mobility_domain, sm->mobility_domain,
00284                   MOBILITY_DOMAIN_ID_LEN);
00285         mdie->ft_capab = ap_mdie && ap_mdie[1] >= 3 ? ap_mdie[4] :
00286                 sm->mdie_ft_capab;
00287 
00288         /* FTIE[SNonce, [R1KH-ID,] R0KH-ID ] */
00289         ftie_pos = pos;
00290         *pos++ = WLAN_EID_FAST_BSS_TRANSITION;
00291         ftie_len = pos++;
00292         ftie = (struct rsn_ftie *) pos;
00293         pos += sizeof(*ftie);
00294         os_memcpy(ftie->snonce, sm->snonce, WPA_NONCE_LEN);
00295         if (anonce)
00296                 os_memcpy(ftie->anonce, anonce, WPA_NONCE_LEN);
00297         if (kck) {
00298                 /* R1KH-ID sub-element in third FT message */
00299                 *pos++ = FTIE_SUBELEM_R1KH_ID;
00300                 *pos++ = FT_R1KH_ID_LEN;
00301                 os_memcpy(pos, sm->r1kh_id, FT_R1KH_ID_LEN);
00302                 pos += FT_R1KH_ID_LEN;
00303         }
00304         /* R0KH-ID sub-element */
00305         *pos++ = FTIE_SUBELEM_R0KH_ID;
00306         *pos++ = sm->r0kh_id_len;
00307         os_memcpy(pos, sm->r0kh_id, sm->r0kh_id_len);
00308         pos += sm->r0kh_id_len;
00309         *ftie_len = pos - ftie_len - 1;
00310 
00311         if (ric_ies) {
00312                 /* RIC Request */
00313                 os_memcpy(pos, ric_ies, ric_ies_len);
00314                 pos += ric_ies_len;
00315         }
00316 
00317         if (kck) {
00318                 /*
00319                  * IEEE Std 802.11r-2008, 11A.8.4
00320                  * MIC shall be calculated over:
00321                  * non-AP STA MAC address
00322                  * Target AP MAC address
00323                  * Transaction seq number (5 for ReassocReq, 3 otherwise)
00324                  * RSN IE
00325                  * MDIE
00326                  * FTIE (with MIC field set to 0)
00327                  * RIC-Request (if present)
00328                  */
00329                 /* Information element count */
00330                 ftie->mic_control[1] = 3 + ieee802_11_ie_count(ric_ies,
00331                                                                ric_ies_len);
00332                 if (wpa_ft_mic(kck, sm->own_addr, target_ap, 5,
00333                                ((u8 *) mdie) - 2, 2 + sizeof(*mdie),
00334                                ftie_pos, 2 + *ftie_len,
00335                                (u8 *) rsnie, 2 + rsnie->len, ric_ies,
00336                                ric_ies_len, ftie->mic) < 0) {
00337                         wpa_printf(MSG_INFO, "FT: Failed to calculate MIC");
00338                         os_free(buf);
00339                         return NULL;
00340                 }
00341         }
00342 
00343         *len = pos - buf;
00344 
00345         return buf;
00346 }
00347 
00348 
00349 static int wpa_ft_parse_ftie(const u8 *ie, size_t ie_len,
00350                              struct wpa_ft_ies *parse)
00351 {
00352         const u8 *end, *pos;
00353 
00354         parse->ftie = ie;
00355         parse->ftie_len = ie_len;
00356 
00357         pos = ie + sizeof(struct rsn_ftie);
00358         end = ie + ie_len;
00359 
00360         while (pos + 2 <= end && pos + 2 + pos[1] <= end) {
00361                 switch (pos[0]) {
00362                 case FTIE_SUBELEM_R1KH_ID:
00363                         if (pos[1] != FT_R1KH_ID_LEN) {
00364                                 wpa_printf(MSG_DEBUG, "FT: Invalid R1KH-ID "
00365                                            "length in FTIE: %d", pos[1]);
00366                                 return -1;
00367                         }
00368                         parse->r1kh_id = pos + 2;
00369                         break;
00370                 case FTIE_SUBELEM_GTK:
00371                         parse->gtk = pos + 2;
00372                         parse->gtk_len = pos[1];
00373                         break;
00374                 case FTIE_SUBELEM_R0KH_ID:
00375                         if (pos[1] < 1 || pos[1] > FT_R0KH_ID_MAX_LEN) {
00376                                 wpa_printf(MSG_DEBUG, "FT: Invalid R0KH-ID "
00377                                            "length in FTIE: %d", pos[1]);
00378                                 return -1;
00379                         }
00380                         parse->r0kh_id = pos + 2;
00381                         parse->r0kh_id_len = pos[1];
00382                         break;
00383 #ifdef CONFIG_IEEE80211W
00384                 case FTIE_SUBELEM_IGTK:
00385                         parse->igtk = pos + 2;
00386                         parse->igtk_len = pos[1];
00387                         break;
00388 #endif /* CONFIG_IEEE80211W */
00389                 }
00390 
00391                 pos += 2 + pos[1];
00392         }
00393 
00394         return 0;
00395 }
00396 
00397 
00398 static int wpa_ft_parse_ies(const u8 *ies, size_t ies_len,
00399                             struct wpa_ft_ies *parse)
00400 {
00401         const u8 *end, *pos;
00402         struct wpa_ie_data data;
00403         int ret;
00404         const struct rsn_ftie *ftie;
00405         int prot_ie_count = 0;
00406 
00407         os_memset(parse, 0, sizeof(*parse));
00408         if (ies == NULL)
00409                 return 0;
00410 
00411         pos = ies;
00412         end = ies + ies_len;
00413         while (pos + 2 <= end && pos + 2 + pos[1] <= end) {
00414                 switch (pos[0]) {
00415                 case WLAN_EID_RSN:
00416                         parse->rsn = pos + 2;
00417                         parse->rsn_len = pos[1];
00418                         ret = wpa_parse_wpa_ie_rsn(parse->rsn - 2,
00419                                                    parse->rsn_len + 2,
00420                                                    &data);
00421                         if (ret < 0) {
00422                                 wpa_printf(MSG_DEBUG, "FT: Failed to parse "
00423                                            "RSN IE: %d", ret);
00424                                 return -1;
00425                         }
00426                         if (data.num_pmkid == 1 && data.pmkid)
00427                                 parse->rsn_pmkid = data.pmkid;
00428                         break;
00429                 case WLAN_EID_MOBILITY_DOMAIN:
00430                         parse->mdie = pos + 2;
00431                         parse->mdie_len = pos[1];
00432                         break;
00433                 case WLAN_EID_FAST_BSS_TRANSITION:
00434                         if (pos[1] < sizeof(*ftie))
00435                                 return -1;
00436                         ftie = (const struct rsn_ftie *) (pos + 2);
00437                         prot_ie_count = ftie->mic_control[1];
00438                         if (wpa_ft_parse_ftie(pos + 2, pos[1], parse) < 0)
00439                                 return -1;
00440                         break;
00441                 case WLAN_EID_TIMEOUT_INTERVAL:
00442                         parse->tie = pos + 2;
00443                         parse->tie_len = pos[1];
00444                         break;
00445                 case WLAN_EID_RIC_DATA:
00446                         if (parse->ric == NULL)
00447                                 parse->ric = pos;
00448                 }
00449 
00450                 pos += 2 + pos[1];
00451         }
00452 
00453         if (prot_ie_count == 0)
00454                 return 0; /* no MIC */
00455 
00456         /*
00457          * Check that the protected IE count matches with IEs included in the
00458          * frame.
00459          */
00460         if (parse->rsn)
00461                 prot_ie_count--;
00462         if (parse->mdie)
00463                 prot_ie_count--;
00464         if (parse->ftie)
00465                 prot_ie_count--;
00466         if (parse->tie)
00467                 prot_ie_count--;
00468         if (prot_ie_count < 0) {
00469                 wpa_printf(MSG_DEBUG, "FT: Some required IEs not included in "
00470                            "the protected IE count");
00471                 return -1;
00472         }
00473 
00474         if (prot_ie_count == 0 && parse->ric) {
00475                 wpa_printf(MSG_DEBUG, "FT: RIC IE(s) in the frame, but not "
00476                            "included in protected IE count");
00477                 return -1;
00478         }
00479 
00480         /* Determine the end of the RIC IE(s) */
00481         pos = parse->ric;
00482         while (pos && pos + 2 <= end && pos + 2 + pos[1] <= end &&
00483                prot_ie_count) {
00484                 prot_ie_count--;
00485                 pos += 2 + pos[1];
00486         }
00487         parse->ric_len = pos - parse->ric;
00488         if (prot_ie_count) {
00489                 wpa_printf(MSG_DEBUG, "FT: %d protected IEs missing from "
00490                            "frame", (int) prot_ie_count);
00491                 return -1;
00492         }
00493 
00494         return 0;
00495 }
00496 
00497 
00498 static int wpa_ft_install_ptk(struct wpa_sm *sm, const u8 *bssid)
00499 {
00500         int keylen;
00501         enum wpa_alg alg;
00502         u8 null_rsc[6] = { 0, 0, 0, 0, 0, 0 };
00503 
00504         wpa_printf(MSG_DEBUG, "FT: Installing PTK to the driver.");
00505 
00506         switch (sm->pairwise_cipher) {
00507         case WPA_CIPHER_CCMP:
00508                 alg = WPA_ALG_CCMP;
00509                 keylen = 16;
00510                 break;
00511         case WPA_CIPHER_TKIP:
00512                 alg = WPA_ALG_TKIP;
00513                 keylen = 32;
00514                 break;
00515         default:
00516                 wpa_printf(MSG_WARNING, "FT: Unsupported pairwise cipher %d",
00517                            sm->pairwise_cipher);
00518                 return -1;
00519         }
00520 
00521         if (wpa_sm_set_key(sm, alg, bssid, 0, 1, null_rsc,
00522                            sizeof(null_rsc), (u8 *) sm->ptk.tk1, keylen) < 0) {
00523                 wpa_printf(MSG_WARNING, "FT: Failed to set PTK to the driver");
00524                 return -1;
00525         }
00526 
00527         return 0;
00528 }
00529 
00530 
00537 int wpa_ft_prepare_auth_request(struct wpa_sm *sm, const u8 *mdie)
00538 {
00539         u8 *ft_ies;
00540         size_t ft_ies_len;
00541 
00542         /* Generate a new SNonce */
00543         if (os_get_random(sm->snonce, WPA_NONCE_LEN)) {
00544                 wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
00545                 return -1;
00546         }
00547 
00548         ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
00549                                     NULL, sm->bssid, NULL, 0, mdie);
00550         if (ft_ies) {
00551                 wpa_sm_update_ft_ies(sm, sm->mobility_domain,
00552                                      ft_ies, ft_ies_len);
00553                 os_free(ft_ies);
00554         }
00555 
00556         return 0;
00557 }
00558 
00559 
00560 int wpa_ft_process_response(struct wpa_sm *sm, const u8 *ies, size_t ies_len,
00561                             int ft_action, const u8 *target_ap,
00562                             const u8 *ric_ies, size_t ric_ies_len)
00563 {
00564         u8 *ft_ies;
00565         size_t ft_ies_len, ptk_len;
00566         struct wpa_ft_ies parse;
00567         struct rsn_mdie *mdie;
00568         struct rsn_ftie *ftie;
00569         u8 ptk_name[WPA_PMK_NAME_LEN];
00570         int ret;
00571         const u8 *bssid;
00572 
00573         wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
00574         wpa_hexdump(MSG_DEBUG, "FT: RIC IEs", ric_ies, ric_ies_len);
00575 
00576         if (ft_action) {
00577                 if (!sm->over_the_ds_in_progress) {
00578                         wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
00579                                    "- drop FT Action Response");
00580                         return -1;
00581                 }
00582 
00583                 if (os_memcmp(target_ap, sm->target_ap, ETH_ALEN) != 0) {
00584                         wpa_printf(MSG_DEBUG, "FT: No over-the-DS in progress "
00585                                    "with this Target AP - drop FT Action "
00586                                    "Response");
00587                         return -1;
00588                 }
00589         }
00590 
00591         if (sm->key_mgmt != WPA_KEY_MGMT_FT_IEEE8021X &&
00592             sm->key_mgmt != WPA_KEY_MGMT_FT_PSK) {
00593                 wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
00594                            "enabled for this connection");
00595                 return -1;
00596         }
00597 
00598         if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
00599                 wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
00600                 return -1;
00601         }
00602 
00603         mdie = (struct rsn_mdie *) parse.mdie;
00604         if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
00605             os_memcmp(mdie->mobility_domain, sm->mobility_domain,
00606                       MOBILITY_DOMAIN_ID_LEN) != 0) {
00607                 wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
00608                 return -1;
00609         }
00610 
00611         ftie = (struct rsn_ftie *) parse.ftie;
00612         if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
00613                 wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
00614                 return -1;
00615         }
00616 
00617         if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
00618                 wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
00619                 wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
00620                             ftie->snonce, WPA_NONCE_LEN);
00621                 wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
00622                             sm->snonce, WPA_NONCE_LEN);
00623                 return -1;
00624         }
00625 
00626         if (parse.r0kh_id == NULL) {
00627                 wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
00628                 return -1;
00629         }
00630 
00631         if (parse.r0kh_id_len != sm->r0kh_id_len ||
00632             os_memcmp(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0) {
00633                 wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
00634                            "the current R0KH-ID");
00635                 wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
00636                             parse.r0kh_id, parse.r0kh_id_len);
00637                 wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
00638                             sm->r0kh_id, sm->r0kh_id_len);
00639                 return -1;
00640         }
00641 
00642         if (parse.r1kh_id == NULL) {
00643                 wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
00644                 return -1;
00645         }
00646 
00647         if (parse.rsn_pmkid == NULL ||
00648             os_memcmp(parse.rsn_pmkid, sm->pmk_r0_name, WPA_PMK_NAME_LEN)) {
00649                 wpa_printf(MSG_DEBUG, "FT: No matching PMKR0Name (PMKID) in "
00650                            "RSNIE");
00651                 return -1;
00652         }
00653 
00654         os_memcpy(sm->r1kh_id, parse.r1kh_id, FT_R1KH_ID_LEN);
00655         wpa_hexdump(MSG_DEBUG, "FT: R1KH-ID", sm->r1kh_id, FT_R1KH_ID_LEN);
00656         wpa_hexdump(MSG_DEBUG, "FT: SNonce", sm->snonce, WPA_NONCE_LEN);
00657         wpa_hexdump(MSG_DEBUG, "FT: ANonce", ftie->anonce, WPA_NONCE_LEN);
00658         os_memcpy(sm->anonce, ftie->anonce, WPA_NONCE_LEN);
00659         wpa_derive_pmk_r1(sm->pmk_r0, sm->pmk_r0_name, sm->r1kh_id,
00660                           sm->own_addr, sm->pmk_r1, sm->pmk_r1_name);
00661         wpa_hexdump_key(MSG_DEBUG, "FT: PMK-R1", sm->pmk_r1, PMK_LEN);
00662         wpa_hexdump(MSG_DEBUG, "FT: PMKR1Name",
00663                     sm->pmk_r1_name, WPA_PMK_NAME_LEN);
00664 
00665         bssid = target_ap;
00666         ptk_len = sm->pairwise_cipher == WPA_CIPHER_CCMP ? 48 : 64;
00667         wpa_pmk_r1_to_ptk(sm->pmk_r1, sm->snonce, ftie->anonce, sm->own_addr,
00668                           bssid, sm->pmk_r1_name,
00669                           (u8 *) &sm->ptk, ptk_len, ptk_name);
00670         wpa_hexdump_key(MSG_DEBUG, "FT: PTK",
00671                         (u8 *) &sm->ptk, ptk_len);
00672         wpa_hexdump(MSG_DEBUG, "FT: PTKName", ptk_name, WPA_PMK_NAME_LEN);
00673 
00674         ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, ftie->anonce,
00675                                     sm->pmk_r1_name, sm->ptk.kck, bssid,
00676                                     ric_ies, ric_ies_len,
00677                                     parse.mdie ? parse.mdie - 2 : NULL);
00678         if (ft_ies) {
00679                 wpa_sm_update_ft_ies(sm, sm->mobility_domain,
00680                                      ft_ies, ft_ies_len);
00681                 os_free(ft_ies);
00682         }
00683 
00684         wpa_sm_mark_authenticated(sm, bssid);
00685         ret = wpa_ft_install_ptk(sm, bssid);
00686         if (ret) {
00687                 /*
00688                  * Some drivers do not support key configuration when we are
00689                  * not associated with the target AP. Work around this by
00690                  * trying again after the following reassociation gets
00691                  * completed.
00692                  */
00693                 wpa_printf(MSG_DEBUG, "FT: Failed to set PTK prior to "
00694                            "association - try again after reassociation");
00695                 sm->set_ptk_after_assoc = 1;
00696         } else
00697                 sm->set_ptk_after_assoc = 0;
00698 
00699         sm->ft_completed = 1;
00700         if (ft_action) {
00701                 /*
00702                  * The caller is expected trigger re-association with the
00703                  * Target AP.
00704                  */
00705                 os_memcpy(sm->bssid, target_ap, ETH_ALEN);
00706         }
00707 
00708         return 0;
00709 }
00710 
00711 
00712 int wpa_ft_is_completed(struct wpa_sm *sm)
00713 {
00714         if (sm == NULL)
00715                 return 0;
00716 
00717         if (sm->key_mgmt != WPA_KEY_MGMT_FT_IEEE8021X &&
00718             sm->key_mgmt != WPA_KEY_MGMT_FT_PSK)
00719                 return 0;
00720 
00721         return sm->ft_completed;
00722 }
00723 
00724 
00725 static int wpa_ft_process_gtk_subelem(struct wpa_sm *sm, const u8 *gtk_elem,
00726                                       size_t gtk_elem_len)
00727 {
00728         u8 gtk[32];
00729         int keyidx;
00730         enum wpa_alg alg;
00731         size_t gtk_len, keylen, rsc_len;
00732 
00733         if (gtk_elem == NULL) {
00734                 wpa_printf(MSG_DEBUG, "FT: No GTK included in FTIE");
00735                 return 0;
00736         }
00737 
00738         wpa_hexdump_key(MSG_DEBUG, "FT: Received GTK in Reassoc Resp",
00739                         gtk_elem, gtk_elem_len);
00740 
00741         if (gtk_elem_len < 11 + 24 || (gtk_elem_len - 11) % 8 ||
00742             gtk_elem_len - 19 > sizeof(gtk)) {
00743                 wpa_printf(MSG_DEBUG, "FT: Invalid GTK sub-elem "
00744                            "length %lu", (unsigned long) gtk_elem_len);
00745                 return -1;
00746         }
00747         gtk_len = gtk_elem_len - 19;
00748         if (aes_unwrap(sm->ptk.kek, gtk_len / 8, gtk_elem + 11, gtk)) {
00749                 wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
00750                            "decrypt GTK");
00751                 return -1;
00752         }
00753 
00754         switch (sm->group_cipher) {
00755         case WPA_CIPHER_CCMP:
00756                 keylen = 16;
00757                 rsc_len = 6;
00758                 alg = WPA_ALG_CCMP;
00759                 break;
00760         case WPA_CIPHER_TKIP:
00761                 keylen = 32;
00762                 rsc_len = 6;
00763                 alg = WPA_ALG_TKIP;
00764                 break;
00765         case WPA_CIPHER_WEP104:
00766                 keylen = 13;
00767                 rsc_len = 0;
00768                 alg = WPA_ALG_WEP;
00769                 break;
00770         case WPA_CIPHER_WEP40:
00771                 keylen = 5;
00772                 rsc_len = 0;
00773                 alg = WPA_ALG_WEP;
00774                 break;
00775         default:
00776                 wpa_printf(MSG_WARNING, "WPA: Unsupported Group Cipher %d",
00777                            sm->group_cipher);
00778                 return -1;
00779         }
00780 
00781         if (gtk_len < keylen) {
00782                 wpa_printf(MSG_DEBUG, "FT: Too short GTK in FTIE");
00783                 return -1;
00784         }
00785 
00786         /* Key Info[2] | Key Length[1] | RSC[8] | Key[5..32]. */
00787 
00788         keyidx = WPA_GET_LE16(gtk_elem) & 0x03;
00789 
00790         if (gtk_elem[2] != keylen) {
00791                 wpa_printf(MSG_DEBUG, "FT: GTK length mismatch: received %d "
00792                            "negotiated %lu",
00793                            gtk_elem[2], (unsigned long) keylen);
00794                 return -1;
00795         }
00796 
00797         wpa_hexdump_key(MSG_DEBUG, "FT: GTK from Reassoc Resp", gtk, keylen);
00798         if (wpa_sm_set_key(sm, alg, (u8 *) "\xff\xff\xff\xff\xff\xff",
00799                            keyidx, 0, gtk_elem + 3, rsc_len, gtk, keylen) <
00800             0) {
00801                 wpa_printf(MSG_WARNING, "WPA: Failed to set GTK to the "
00802                            "driver.");
00803                 return -1;
00804         }
00805 
00806         return 0;
00807 }
00808 
00809 
00810 #ifdef CONFIG_IEEE80211W
00811 static int wpa_ft_process_igtk_subelem(struct wpa_sm *sm, const u8 *igtk_elem,
00812                                        size_t igtk_elem_len)
00813 {
00814         u8 igtk[WPA_IGTK_LEN];
00815         u16 keyidx;
00816 
00817         if (sm->mgmt_group_cipher != WPA_CIPHER_AES_128_CMAC)
00818                 return 0;
00819 
00820         if (igtk_elem == NULL) {
00821                 wpa_printf(MSG_DEBUG, "FT: No IGTK included in FTIE");
00822                 return 0;
00823         }
00824 
00825         wpa_hexdump_key(MSG_DEBUG, "FT: Received IGTK in Reassoc Resp",
00826                         igtk_elem, igtk_elem_len);
00827 
00828         if (igtk_elem_len != 2 + 6 + 1 + WPA_IGTK_LEN + 8) {
00829                 wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem "
00830                            "length %lu", (unsigned long) igtk_elem_len);
00831                 return -1;
00832         }
00833         if (igtk_elem[8] != WPA_IGTK_LEN) {
00834                 wpa_printf(MSG_DEBUG, "FT: Invalid IGTK sub-elem Key Length "
00835                            "%d", igtk_elem[8]);
00836                 return -1;
00837         }
00838 
00839         if (aes_unwrap(sm->ptk.kek, WPA_IGTK_LEN / 8, igtk_elem + 9, igtk)) {
00840                 wpa_printf(MSG_WARNING, "FT: AES unwrap failed - could not "
00841                            "decrypt IGTK");
00842                 return -1;
00843         }
00844 
00845         /* KeyID[2] | IPN[6] | Key Length[1] | Key[16+8] */
00846 
00847         keyidx = WPA_GET_LE16(igtk_elem);
00848 
00849         wpa_hexdump_key(MSG_DEBUG, "FT: IGTK from Reassoc Resp", igtk,
00850                         WPA_IGTK_LEN);
00851         if (wpa_sm_set_key(sm, WPA_ALG_IGTK, (u8 *) "\xff\xff\xff\xff\xff\xff",
00852                            keyidx, 0, igtk_elem + 2, 6, igtk, WPA_IGTK_LEN) <
00853             0) {
00854                 wpa_printf(MSG_WARNING, "WPA: Failed to set IGTK to the "
00855                            "driver.");
00856                 return -1;
00857         }
00858 
00859         return 0;
00860 }
00861 #endif /* CONFIG_IEEE80211W */
00862 
00863 
00864 int wpa_ft_validate_reassoc_resp(struct wpa_sm *sm, const u8 *ies,
00865                                  size_t ies_len, const u8 *src_addr)
00866 {
00867         struct wpa_ft_ies parse;
00868         struct rsn_mdie *mdie;
00869         struct rsn_ftie *ftie;
00870         unsigned int count;
00871         u8 mic[16];
00872 
00873         wpa_hexdump(MSG_DEBUG, "FT: Response IEs", ies, ies_len);
00874 
00875         if (sm->key_mgmt != WPA_KEY_MGMT_FT_IEEE8021X &&
00876             sm->key_mgmt != WPA_KEY_MGMT_FT_PSK) {
00877                 wpa_printf(MSG_DEBUG, "FT: Reject FT IEs since FT is not "
00878                            "enabled for this connection");
00879                 return -1;
00880         }
00881 
00882         if (wpa_ft_parse_ies(ies, ies_len, &parse) < 0) {
00883                 wpa_printf(MSG_DEBUG, "FT: Failed to parse IEs");
00884                 return -1;
00885         }
00886 
00887         mdie = (struct rsn_mdie *) parse.mdie;
00888         if (mdie == NULL || parse.mdie_len < sizeof(*mdie) ||
00889             os_memcmp(mdie->mobility_domain, sm->mobility_domain,
00890                       MOBILITY_DOMAIN_ID_LEN) != 0) {
00891                 wpa_printf(MSG_DEBUG, "FT: Invalid MDIE");
00892                 return -1;
00893         }
00894 
00895         ftie = (struct rsn_ftie *) parse.ftie;
00896         if (ftie == NULL || parse.ftie_len < sizeof(*ftie)) {
00897                 wpa_printf(MSG_DEBUG, "FT: Invalid FTIE");
00898                 return -1;
00899         }
00900 
00901         if (os_memcmp(ftie->snonce, sm->snonce, WPA_NONCE_LEN) != 0) {
00902                 wpa_printf(MSG_DEBUG, "FT: SNonce mismatch in FTIE");
00903                 wpa_hexdump(MSG_DEBUG, "FT: Received SNonce",
00904                             ftie->snonce, WPA_NONCE_LEN);
00905                 wpa_hexdump(MSG_DEBUG, "FT: Expected SNonce",
00906                             sm->snonce, WPA_NONCE_LEN);
00907                 return -1;
00908         }
00909 
00910         if (os_memcmp(ftie->anonce, sm->anonce, WPA_NONCE_LEN) != 0) {
00911                 wpa_printf(MSG_DEBUG, "FT: ANonce mismatch in FTIE");
00912                 wpa_hexdump(MSG_DEBUG, "FT: Received ANonce",
00913                             ftie->anonce, WPA_NONCE_LEN);
00914                 wpa_hexdump(MSG_DEBUG, "FT: Expected ANonce",
00915                             sm->anonce, WPA_NONCE_LEN);
00916                 return -1;
00917         }
00918 
00919         if (parse.r0kh_id == NULL) {
00920                 wpa_printf(MSG_DEBUG, "FT: No R0KH-ID subelem in FTIE");
00921                 return -1;
00922         }
00923 
00924         if (parse.r0kh_id_len != sm->r0kh_id_len ||
00925             os_memcmp(parse.r0kh_id, sm->r0kh_id, parse.r0kh_id_len) != 0) {
00926                 wpa_printf(MSG_DEBUG, "FT: R0KH-ID in FTIE did not match with "
00927                            "the current R0KH-ID");
00928                 wpa_hexdump(MSG_DEBUG, "FT: R0KH-ID in FTIE",
00929                             parse.r0kh_id, parse.r0kh_id_len);
00930                 wpa_hexdump(MSG_DEBUG, "FT: The current R0KH-ID",
00931                             sm->r0kh_id, sm->r0kh_id_len);
00932                 return -1;
00933         }
00934 
00935         if (parse.r1kh_id == NULL) {
00936                 wpa_printf(MSG_DEBUG, "FT: No R1KH-ID subelem in FTIE");
00937                 return -1;
00938         }
00939 
00940         if (os_memcmp(parse.r1kh_id, sm->r1kh_id, FT_R1KH_ID_LEN) != 0) {
00941                 wpa_printf(MSG_DEBUG, "FT: Unknown R1KH-ID used in "
00942                            "ReassocResp");
00943                 return -1;
00944         }
00945 
00946         if (parse.rsn_pmkid == NULL ||
00947             os_memcmp(parse.rsn_pmkid, sm->pmk_r1_name, WPA_PMK_NAME_LEN)) {
00948                 wpa_printf(MSG_DEBUG, "FT: No matching PMKR1Name (PMKID) in "
00949                            "RSNIE (pmkid=%d)", !!parse.rsn_pmkid);
00950                 return -1;
00951         }
00952 
00953         count = 3;
00954         if (parse.tie)
00955                 count++;
00956         if (ftie->mic_control[1] != count) {
00957                 wpa_printf(MSG_DEBUG, "FT: Unexpected IE count in MIC "
00958                            "Control: received %u expected %u",
00959                            ftie->mic_control[1], count);
00960                 return -1;
00961         }
00962 
00963         if (wpa_ft_mic(sm->ptk.kck, sm->own_addr, src_addr, 6,
00964                        parse.mdie - 2, parse.mdie_len + 2,
00965                        parse.ftie - 2, parse.ftie_len + 2,
00966                        parse.rsn - 2, parse.rsn_len + 2,
00967                        parse.ric, parse.ric_len,
00968                        mic) < 0) {
00969                 wpa_printf(MSG_DEBUG, "FT: Failed to calculate MIC");
00970                 return -1;
00971         }
00972 
00973         if (os_memcmp(mic, ftie->mic, 16) != 0) {
00974                 wpa_printf(MSG_DEBUG, "FT: Invalid MIC in FTIE");
00975                 wpa_hexdump(MSG_MSGDUMP, "FT: Received MIC", ftie->mic, 16);
00976                 wpa_hexdump(MSG_MSGDUMP, "FT: Calculated MIC", mic, 16);
00977                 return -1;
00978         }
00979 
00980         if (wpa_ft_process_gtk_subelem(sm, parse.gtk, parse.gtk_len) < 0)
00981                 return -1;
00982 
00983 #ifdef CONFIG_IEEE80211W
00984         if (wpa_ft_process_igtk_subelem(sm, parse.igtk, parse.igtk_len) < 0)
00985                 return -1;
00986 #endif /* CONFIG_IEEE80211W */
00987 
00988         if (sm->set_ptk_after_assoc) {
00989                 wpa_printf(MSG_DEBUG, "FT: Try to set PTK again now that we "
00990                            "are associated");
00991                 if (wpa_ft_install_ptk(sm, src_addr) < 0)
00992                         return -1;
00993                 sm->set_ptk_after_assoc = 0;
00994         }
00995 
00996         if (parse.ric) {
00997                 wpa_hexdump(MSG_MSGDUMP, "FT: RIC Response",
00998                             parse.ric, parse.ric_len);
00999                 /* TODO: parse response and inform driver about results */
01000         }
01001 
01002         return 0;
01003 }
01004 
01005 
01013 int wpa_ft_start_over_ds(struct wpa_sm *sm, const u8 *target_ap,
01014                          const u8 *mdie)
01015 {
01016         u8 *ft_ies;
01017         size_t ft_ies_len;
01018 
01019         wpa_printf(MSG_DEBUG, "FT: Request over-the-DS with " MACSTR,
01020                    MAC2STR(target_ap));
01021 
01022         /* Generate a new SNonce */
01023         if (os_get_random(sm->snonce, WPA_NONCE_LEN)) {
01024                 wpa_printf(MSG_INFO, "FT: Failed to generate a new SNonce");
01025                 return -1;
01026         }
01027 
01028         ft_ies = wpa_ft_gen_req_ies(sm, &ft_ies_len, NULL, sm->pmk_r0_name,
01029                                     NULL, target_ap, NULL, 0, mdie);
01030         if (ft_ies) {
01031                 sm->over_the_ds_in_progress = 1;
01032                 os_memcpy(sm->target_ap, target_ap, ETH_ALEN);
01033                 wpa_sm_send_ft_action(sm, 1, target_ap, ft_ies, ft_ies_len);
01034                 os_free(ft_ies);
01035         }
01036 
01037         return 0;
01038 }
01039 
01040 #endif /* CONFIG_IEEE80211R */


wpa_supplicant
Author(s): Package maintained by Blaise Gassend
autogenerated on Thu Jan 2 2014 11:26:39