--- /dev/null
+/*
+ * WPA Supplicant - Mesh RSN routines
+ * Copyright (c) 2013-2014, cozybit, Inc. All rights reserved.
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ */
+
+#include "utils/includes.h"
+
+#include "utils/common.h"
+#include "utils/eloop.h"
+#include "crypto/sha256.h"
+#include "crypto/random.h"
+#include "crypto/aes.h"
+#include "crypto/aes_siv.h"
+#include "rsn_supp/wpa.h"
+#include "ap/hostapd.h"
+#include "ap/wpa_auth.h"
+#include "ap/sta_info.h"
+#include "ap/ieee802_11.h"
+#include "wpa_supplicant_i.h"
+#include "driver_i.h"
+#include "wpas_glue.h"
+#include "mesh_mpm.h"
+#include "mesh_rsn.h"
+
+#define MESH_AUTH_TIMEOUT 10
+#define MESH_AUTH_RETRY 3
+
+void mesh_auth_timer(void *eloop_ctx, void *user_data)
+{
+ struct wpa_supplicant *wpa_s = eloop_ctx;
+ struct sta_info *sta = user_data;
+ struct hostapd_data *hapd;
+
+ if (sta->sae->state != SAE_ACCEPTED) {
+ wpa_printf(MSG_DEBUG, "AUTH: Re-authenticate with " MACSTR
+ " (attempt %d) ",
+ MAC2STR(sta->addr), sta->sae_auth_retry);
+ wpa_msg(wpa_s, MSG_INFO, MESH_SAE_AUTH_FAILURE "addr=" MACSTR,
+ MAC2STR(sta->addr));
+ if (sta->sae_auth_retry < MESH_AUTH_RETRY) {
+ mesh_rsn_auth_sae_sta(wpa_s, sta);
+ } else {
+ hapd = wpa_s->ifmsh->bss[0];
+
+ if (sta->sae_auth_retry > MESH_AUTH_RETRY) {
+ ap_free_sta(hapd, sta);
+ return;
+ }
+
+ /* block the STA if exceeded the number of attempts */
+ wpa_mesh_set_plink_state(wpa_s, sta, PLINK_BLOCKED);
+ sta->sae->state = SAE_NOTHING;
+ wpa_msg(wpa_s, MSG_INFO, MESH_SAE_AUTH_BLOCKED "addr="
+ MACSTR " duration=%d",
+ MAC2STR(sta->addr),
+ hapd->conf->ap_max_inactivity);
+ }
+ sta->sae_auth_retry++;
+ }
+}
+
+
+static void auth_logger(void *ctx, const u8 *addr, logger_level level,
+ const char *txt)
+{
+ if (addr)
+ wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
+ MAC2STR(addr), txt);
+ else
+ wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
+}
+
+
+static const u8 *auth_get_psk(void *ctx, const u8 *addr,
+ const u8 *p2p_dev_addr, const u8 *prev_psk)
+{
+ struct mesh_rsn *mesh_rsn = ctx;
+ struct hostapd_data *hapd = mesh_rsn->wpa_s->ifmsh->bss[0];
+ struct sta_info *sta = ap_get_sta(hapd, addr);
+
+ wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
+ __func__, MAC2STR(addr), prev_psk);
+
+ if (sta && sta->auth_alg == WLAN_AUTH_SAE) {
+ if (!sta->sae || prev_psk)
+ return NULL;
+ return sta->sae->pmk;
+ }
+
+ return NULL;
+}
+
+
+static int auth_set_key(void *ctx, int vlan_id, enum wpa_alg alg,
+ const u8 *addr, int idx, u8 *key, size_t key_len)
+{
+ struct mesh_rsn *mesh_rsn = ctx;
+ u8 seq[6];
+
+ os_memset(seq, 0, sizeof(seq));
+
+ if (addr) {
+ wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d addr=" MACSTR
+ " key_idx=%d)",
+ __func__, alg, MAC2STR(addr), idx);
+ } else {
+ wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d key_idx=%d)",
+ __func__, alg, idx);
+ }
+ wpa_hexdump_key(MSG_DEBUG, "AUTH: set_key - key", key, key_len);
+
+ return wpa_drv_set_key(mesh_rsn->wpa_s, alg, addr, idx,
+ 1, seq, 6, key, key_len);
+}
+
+
+static int auth_start_ampe(void *ctx, const u8 *addr)
+{
+ struct mesh_rsn *mesh_rsn = ctx;
+ struct hostapd_data *hapd;
+ struct sta_info *sta;
+
+ if (mesh_rsn->wpa_s->current_ssid->mode != WPAS_MODE_MESH)
+ return -1;
+
+ hapd = mesh_rsn->wpa_s->ifmsh->bss[0];
+ sta = ap_get_sta(hapd, addr);
+ if (sta)
+ eloop_cancel_timeout(mesh_auth_timer, mesh_rsn->wpa_s, sta);
+
+ mesh_mpm_auth_peer(mesh_rsn->wpa_s, addr);
+ return 0;
+}
+
+
+static int __mesh_rsn_auth_init(struct mesh_rsn *rsn, const u8 *addr,
+ enum mfp_options ieee80211w)
+{
+ struct wpa_auth_config conf;
+ struct wpa_auth_callbacks cb;
+ u8 seq[6] = {};
+
+ wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
+
+ os_memset(&conf, 0, sizeof(conf));
+ conf.wpa = WPA_PROTO_RSN;
+ conf.wpa_key_mgmt = WPA_KEY_MGMT_SAE;
+ conf.wpa_pairwise = rsn->pairwise_cipher;
+ conf.rsn_pairwise = rsn->pairwise_cipher;
+ conf.wpa_group = rsn->group_cipher;
+ conf.eapol_version = 0;
+ conf.wpa_group_rekey = -1;
+#ifdef CONFIG_IEEE80211W
+ conf.ieee80211w = ieee80211w;
+ if (ieee80211w != NO_MGMT_FRAME_PROTECTION)
+ conf.group_mgmt_cipher = rsn->mgmt_group_cipher;
+#endif /* CONFIG_IEEE80211W */
+
+ os_memset(&cb, 0, sizeof(cb));
+ cb.ctx = rsn;
+ cb.logger = auth_logger;
+ cb.get_psk = auth_get_psk;
+ cb.set_key = auth_set_key;
+ cb.start_ampe = auth_start_ampe;
+
+ rsn->auth = wpa_init(addr, &conf, &cb);
+ if (rsn->auth == NULL) {
+ wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
+ return -1;
+ }
+
+ /* TODO: support rekeying */
+ rsn->mgtk_len = wpa_cipher_key_len(conf.wpa_group);
+ if (random_get_bytes(rsn->mgtk, rsn->mgtk_len) < 0)
+ return -1;
+ rsn->mgtk_key_id = 1;
+
+#ifdef CONFIG_IEEE80211W
+ if (ieee80211w != NO_MGMT_FRAME_PROTECTION) {
+ rsn->igtk_len = wpa_cipher_key_len(conf.group_mgmt_cipher);
+ if (random_get_bytes(rsn->igtk, rsn->igtk_len) < 0)
+ return -1;
+ rsn->igtk_key_id = 4;
+
+ /* group mgmt */
+ wpa_hexdump_key(MSG_DEBUG, "mesh: Own TX IGTK",
+ rsn->igtk, rsn->igtk_len);
+ wpa_drv_set_key(rsn->wpa_s,
+ wpa_cipher_to_alg(rsn->mgmt_group_cipher), NULL,
+ rsn->igtk_key_id, 1,
+ seq, sizeof(seq), rsn->igtk, rsn->igtk_len);
+ }
+#endif /* CONFIG_IEEE80211W */
+
+ /* group privacy / data frames */
+ wpa_hexdump_key(MSG_DEBUG, "mesh: Own TX MGTK",
+ rsn->mgtk, rsn->mgtk_len);
+ wpa_drv_set_key(rsn->wpa_s, wpa_cipher_to_alg(rsn->group_cipher), NULL,
+ rsn->mgtk_key_id, 1, seq, sizeof(seq),
+ rsn->mgtk, rsn->mgtk_len);
+
+ return 0;
+}
+
+
+static void mesh_rsn_deinit(struct mesh_rsn *rsn)
+{
+ os_memset(rsn->mgtk, 0, sizeof(rsn->mgtk));
+ rsn->mgtk_len = 0;
+ os_memset(rsn->igtk, 0, sizeof(rsn->igtk));
+ rsn->igtk_len = 0;
+ if (rsn->auth)
+ wpa_deinit(rsn->auth);
+}
+
+
+struct mesh_rsn *mesh_rsn_auth_init(struct wpa_supplicant *wpa_s,
+ struct mesh_conf *conf)
+{
+ struct mesh_rsn *mesh_rsn;
+ struct hostapd_data *bss = wpa_s->ifmsh->bss[0];
+ const u8 *ie;
+ size_t ie_len;
+
+ mesh_rsn = os_zalloc(sizeof(*mesh_rsn));
+ if (mesh_rsn == NULL)
+ return NULL;
+ mesh_rsn->wpa_s = wpa_s;
+ mesh_rsn->pairwise_cipher = conf->pairwise_cipher;
+ mesh_rsn->group_cipher = conf->group_cipher;
+ mesh_rsn->mgmt_group_cipher = conf->mgmt_group_cipher;
+
+ if (__mesh_rsn_auth_init(mesh_rsn, wpa_s->own_addr,
+ conf->ieee80211w) < 0) {
+ mesh_rsn_deinit(mesh_rsn);
+ os_free(mesh_rsn);
+ return NULL;
+ }
+
+ bss->wpa_auth = mesh_rsn->auth;
+
+ ie = wpa_auth_get_wpa_ie(mesh_rsn->auth, &ie_len);
+ conf->rsn_ie = (u8 *) ie;
+ conf->rsn_ie_len = ie_len;
+
+ wpa_supplicant_rsn_supp_set_config(wpa_s, wpa_s->current_ssid);
+
+ return mesh_rsn;
+}
+
+
+static int index_within_array(const int *array, int idx)
+{
+ int i;
+
+ for (i = 0; i < idx; i++) {
+ if (array[i] == -1)
+ return 0;
+ }
+
+ return 1;
+}
+
+
+static int mesh_rsn_sae_group(struct wpa_supplicant *wpa_s,
+ struct sae_data *sae)
+{
+ int *groups = wpa_s->ifmsh->bss[0]->conf->sae_groups;
+
+ /* Configuration may have changed, so validate current index */
+ if (!index_within_array(groups, wpa_s->mesh_rsn->sae_group_index))
+ return -1;
+
+ for (;;) {
+ int group = groups[wpa_s->mesh_rsn->sae_group_index];
+
+ if (group <= 0)
+ break;
+ if (sae_set_group(sae, group) == 0) {
+ wpa_dbg(wpa_s, MSG_DEBUG, "SME: Selected SAE group %d",
+ sae->group);
+ return 0;
+ }
+ wpa_s->mesh_rsn->sae_group_index++;
+ }
+
+ return -1;
+}
+
+
+static int mesh_rsn_build_sae_commit(struct wpa_supplicant *wpa_s,
+ struct wpa_ssid *ssid,
+ struct sta_info *sta)
+{
+ if (ssid->passphrase == NULL) {
+ wpa_msg(wpa_s, MSG_DEBUG, "SAE: No password available");
+ return -1;
+ }
+
+ if (mesh_rsn_sae_group(wpa_s, sta->sae) < 0) {
+ wpa_msg(wpa_s, MSG_DEBUG, "SAE: Failed to select group");
+ return -1;
+ }
+
+ return sae_prepare_commit(wpa_s->own_addr, sta->addr,
+ (u8 *) ssid->passphrase,
+ os_strlen(ssid->passphrase), sta->sae);
+}
+
+
+/* initiate new SAE authentication with sta */
+int mesh_rsn_auth_sae_sta(struct wpa_supplicant *wpa_s,
+ struct sta_info *sta)
+{
+ struct hostapd_data *hapd = wpa_s->ifmsh->bss[0];
+ struct wpa_ssid *ssid = wpa_s->current_ssid;
+ struct rsn_pmksa_cache_entry *pmksa;
+ unsigned int rnd;
+ int ret;
+
+ if (!ssid) {
+ wpa_msg(wpa_s, MSG_DEBUG,
+ "AUTH: No current_ssid known to initiate new SAE");
+ return -1;
+ }
+
+ if (!sta->sae) {
+ sta->sae = os_zalloc(sizeof(*sta->sae));
+ if (sta->sae == NULL)
+ return -1;
+ }
+
+ pmksa = wpa_auth_pmksa_get(hapd->wpa_auth, sta->addr);
+ if (pmksa) {
+ if (!sta->wpa_sm)
+ sta->wpa_sm = wpa_auth_sta_init(hapd->wpa_auth,
+ sta->addr, NULL);
+ if (!sta->wpa_sm) {
+ wpa_printf(MSG_ERROR,
+ "mesh: Failed to initialize RSN state machine");
+ return -1;
+ }
+
+ wpa_printf(MSG_DEBUG,
+ "AUTH: Mesh PMKSA cache entry found for " MACSTR
+ " - try to use PMKSA caching instead of new SAE authentication",
+ MAC2STR(sta->addr));
+ wpa_auth_pmksa_set_to_sm(pmksa, sta->wpa_sm, hapd->wpa_auth,
+ sta->sae->pmkid, sta->sae->pmk);
+ sae_accept_sta(hapd, sta);
+ sta->mesh_sae_pmksa_caching = 1;
+ return 0;
+ }
+ sta->mesh_sae_pmksa_caching = 0;
+
+ if (mesh_rsn_build_sae_commit(wpa_s, ssid, sta))
+ return -1;
+
+ wpa_msg(wpa_s, MSG_DEBUG,
+ "AUTH: started authentication with SAE peer: " MACSTR,
+ MAC2STR(sta->addr));
+
+ ret = auth_sae_init_committed(hapd, sta);
+ if (ret)
+ return ret;
+
+ eloop_cancel_timeout(mesh_auth_timer, wpa_s, sta);
+ rnd = rand() % MESH_AUTH_TIMEOUT;
+ eloop_register_timeout(MESH_AUTH_TIMEOUT + rnd, 0, mesh_auth_timer,
+ wpa_s, sta);
+ return 0;
+}
+
+
+void mesh_rsn_get_pmkid(struct mesh_rsn *rsn, struct sta_info *sta, u8 *pmkid)
+{
+ os_memcpy(pmkid, sta->sae->pmkid, SAE_PMKID_LEN);
+}
+
+
+static void
+mesh_rsn_derive_aek(struct mesh_rsn *rsn, struct sta_info *sta)
+{
+ u8 *myaddr = rsn->wpa_s->own_addr;
+ u8 *peer = sta->addr;
+ u8 *addr1, *addr2;
+ u8 context[RSN_SELECTOR_LEN + 2 * ETH_ALEN], *ptr = context;
+
+ /*
+ * AEK = KDF-Hash-256(PMK, "AEK Derivation", Selected AKM Suite ||
+ * min(localMAC, peerMAC) || max(localMAC, peerMAC))
+ */
+ /* Selected AKM Suite: SAE */
+ RSN_SELECTOR_PUT(ptr, RSN_AUTH_KEY_MGMT_SAE);
+ ptr += RSN_SELECTOR_LEN;
+
+ if (os_memcmp(myaddr, peer, ETH_ALEN) < 0) {
+ addr1 = myaddr;
+ addr2 = peer;
+ } else {
+ addr1 = peer;
+ addr2 = myaddr;
+ }
+ os_memcpy(ptr, addr1, ETH_ALEN);
+ ptr += ETH_ALEN;
+ os_memcpy(ptr, addr2, ETH_ALEN);
+
+ sha256_prf(sta->sae->pmk, sizeof(sta->sae->pmk), "AEK Derivation",
+ context, sizeof(context), sta->aek, sizeof(sta->aek));
+}
+
+
+/* derive mesh temporal key from pmk */
+int mesh_rsn_derive_mtk(struct wpa_supplicant *wpa_s, struct sta_info *sta)
+{
+ u8 *ptr;
+ u8 *min, *max;
+ u8 *myaddr = wpa_s->own_addr;
+ u8 *peer = sta->addr;
+ u8 context[2 * WPA_NONCE_LEN + 2 * 2 + RSN_SELECTOR_LEN + 2 * ETH_ALEN];
+
+ /*
+ * MTK = KDF-Hash-Length(PMK, "Temporal Key Derivation", min(localNonce,
+ * peerNonce) || max(localNonce, peerNonce) || min(localLinkID,
+ * peerLinkID) || max(localLinkID, peerLinkID) || Selected AKM Suite ||
+ * min(localMAC, peerMAC) || max(localMAC, peerMAC))
+ */
+ ptr = context;
+ if (os_memcmp(sta->my_nonce, sta->peer_nonce, WPA_NONCE_LEN) < 0) {
+ min = sta->my_nonce;
+ max = sta->peer_nonce;
+ } else {
+ min = sta->peer_nonce;
+ max = sta->my_nonce;
+ }
+ os_memcpy(ptr, min, WPA_NONCE_LEN);
+ ptr += WPA_NONCE_LEN;
+ os_memcpy(ptr, max, WPA_NONCE_LEN);
+ ptr += WPA_NONCE_LEN;
+
+ if (sta->my_lid < sta->peer_lid) {
+ WPA_PUT_LE16(ptr, sta->my_lid);
+ ptr += 2;
+ WPA_PUT_LE16(ptr, sta->peer_lid);
+ ptr += 2;
+ } else {
+ WPA_PUT_LE16(ptr, sta->peer_lid);
+ ptr += 2;
+ WPA_PUT_LE16(ptr, sta->my_lid);
+ ptr += 2;
+ }
+
+ /* Selected AKM Suite: SAE */
+ RSN_SELECTOR_PUT(ptr, RSN_AUTH_KEY_MGMT_SAE);
+ ptr += RSN_SELECTOR_LEN;
+
+ if (os_memcmp(myaddr, peer, ETH_ALEN) < 0) {
+ min = myaddr;
+ max = peer;
+ } else {
+ min = peer;
+ max = myaddr;
+ }
+ os_memcpy(ptr, min, ETH_ALEN);
+ ptr += ETH_ALEN;
+ os_memcpy(ptr, max, ETH_ALEN);
+
+ sta->mtk_len = wpa_cipher_key_len(wpa_s->mesh_rsn->pairwise_cipher);
+ sha256_prf(sta->sae->pmk, SAE_PMK_LEN,
+ "Temporal Key Derivation", context, sizeof(context),
+ sta->mtk, sta->mtk_len);
+ return 0;
+}
+
+
+void mesh_rsn_init_ampe_sta(struct wpa_supplicant *wpa_s, struct sta_info *sta)
+{
+ if (random_get_bytes(sta->my_nonce, WPA_NONCE_LEN) < 0) {
+ wpa_printf(MSG_INFO, "mesh: Failed to derive random nonce");
+ /* TODO: How to handle this more cleanly? */
+ }
+ os_memset(sta->peer_nonce, 0, WPA_NONCE_LEN);
+ mesh_rsn_derive_aek(wpa_s->mesh_rsn, sta);
+}
+
+
+/* insert AMPE and encrypted MIC at @ie.
+ * @mesh_rsn: mesh RSN context
+ * @sta: STA we're sending to
+ * @cat: pointer to category code in frame header.
+ * @buf: wpabuf to add encrypted AMPE and MIC to.
+ * */
+int mesh_rsn_protect_frame(struct mesh_rsn *rsn, struct sta_info *sta,
+ const u8 *cat, struct wpabuf *buf)
+{
+ struct ieee80211_ampe_ie *ampe;
+ u8 const *ie = wpabuf_head_u8(buf) + wpabuf_len(buf);
+ u8 *ampe_ie, *pos, *mic_payload;
+ const u8 *aad[] = { rsn->wpa_s->own_addr, sta->addr, cat };
+ const size_t aad_len[] = { ETH_ALEN, ETH_ALEN, ie - cat };
+ int ret = 0;
+ size_t len;
+
+ len = sizeof(*ampe);
+ if (cat[1] == PLINK_OPEN)
+ len += rsn->mgtk_len + WPA_KEY_RSC_LEN + 4;
+#ifdef CONFIG_IEEE80211W
+ if (cat[1] == PLINK_OPEN && rsn->igtk_len)
+ len += 2 + 6 + rsn->igtk_len;
+#endif /* CONFIG_IEEE80211W */
+
+ if (2 + AES_BLOCK_SIZE + 2 + len > wpabuf_tailroom(buf)) {
+ wpa_printf(MSG_ERROR, "protect frame: buffer too small");
+ return -EINVAL;
+ }
+
+ ampe_ie = os_zalloc(2 + len);
+ if (!ampe_ie) {
+ wpa_printf(MSG_ERROR, "protect frame: out of memory");
+ return -ENOMEM;
+ }
+
+ /* IE: AMPE */
+ ampe_ie[0] = WLAN_EID_AMPE;
+ ampe_ie[1] = len;
+ ampe = (struct ieee80211_ampe_ie *) (ampe_ie + 2);
+
+ RSN_SELECTOR_PUT(ampe->selected_pairwise_suite,
+ RSN_CIPHER_SUITE_CCMP);
+ os_memcpy(ampe->local_nonce, sta->my_nonce, WPA_NONCE_LEN);
+ os_memcpy(ampe->peer_nonce, sta->peer_nonce, WPA_NONCE_LEN);
+
+ pos = (u8 *) (ampe + 1);
+ if (cat[1] != PLINK_OPEN)
+ goto skip_keys;
+
+ /* TODO: Key Replay Counter[8] optionally for
+ * Mesh Group Key Inform/Acknowledge frames */
+
+ /* TODO: static mgtk for now since we don't support rekeying! */
+ /*
+ * GTKdata[variable]:
+ * MGTK[variable] || Key RSC[8] || GTKExpirationTime[4]
+ */
+ os_memcpy(pos, rsn->mgtk, rsn->mgtk_len);
+ pos += rsn->mgtk_len;
+ wpa_drv_get_seqnum(rsn->wpa_s, NULL, rsn->mgtk_key_id, pos);
+ pos += WPA_KEY_RSC_LEN;
+ /* Use fixed GTKExpirationTime for now */
+ WPA_PUT_LE32(pos, 0xffffffff);
+ pos += 4;
+
+#ifdef CONFIG_IEEE80211W
+ /*
+ * IGTKdata[variable]:
+ * Key ID[2], IPN[6], IGTK[variable]
+ */
+ if (rsn->igtk_len) {
+ WPA_PUT_LE16(pos, rsn->igtk_key_id);
+ pos += 2;
+ wpa_drv_get_seqnum(rsn->wpa_s, NULL, rsn->igtk_key_id, pos);
+ pos += 6;
+ os_memcpy(pos, rsn->igtk, rsn->igtk_len);
+ }
+#endif /* CONFIG_IEEE80211W */
+
+skip_keys:
+ wpa_hexdump_key(MSG_DEBUG, "mesh: Plaintext AMPE element",
+ ampe_ie, 2 + len);
+
+ /* IE: MIC */
+ wpabuf_put_u8(buf, WLAN_EID_MIC);
+ wpabuf_put_u8(buf, AES_BLOCK_SIZE);
+ /* MIC field is output ciphertext */
+
+ /* encrypt after MIC */
+ mic_payload = wpabuf_put(buf, 2 + len + AES_BLOCK_SIZE);
+
+ if (aes_siv_encrypt(sta->aek, ampe_ie, 2 + len, 3,
+ aad, aad_len, mic_payload)) {
+ wpa_printf(MSG_ERROR, "protect frame: failed to encrypt");
+ ret = -ENOMEM;
+ }
+
+ os_free(ampe_ie);
+
+ return ret;
+}
+
+
+int mesh_rsn_process_ampe(struct wpa_supplicant *wpa_s, struct sta_info *sta,
+ struct ieee802_11_elems *elems, const u8 *cat,
+ const u8 *chosen_pmk,
+ const u8 *start, size_t elems_len)
+{
+ int ret = 0;
+ struct ieee80211_ampe_ie *ampe;
+ u8 null_nonce[WPA_NONCE_LEN] = {};
+ u8 ampe_eid;
+ u8 ampe_ie_len;
+ u8 *ampe_buf, *crypt = NULL, *pos, *end;
+ size_t crypt_len;
+ const u8 *aad[] = { sta->addr, wpa_s->own_addr, cat };
+ const size_t aad_len[] = { ETH_ALEN, ETH_ALEN,
+ (elems->mic - 2) - cat };
+ size_t key_len;
+
+ if (!sta->sae) {
+ struct hostapd_data *hapd = wpa_s->ifmsh->bss[0];
+
+ if (!wpa_auth_pmksa_get(hapd->wpa_auth, sta->addr)) {
+ wpa_printf(MSG_INFO,
+ "Mesh RSN: SAE is not prepared yet");
+ return -1;
+ }
+ mesh_rsn_auth_sae_sta(wpa_s, sta);
+ }
+
+ if (chosen_pmk && os_memcmp(chosen_pmk, sta->sae->pmkid, PMKID_LEN)) {
+ wpa_msg(wpa_s, MSG_DEBUG,
+ "Mesh RSN: Invalid PMKID (Chosen PMK did not match calculated PMKID)");
+ return -1;
+ }
+
+ if (!elems->mic || elems->mic_len < AES_BLOCK_SIZE) {
+ wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: missing mic ie");
+ return -1;
+ }
+
+ ampe_buf = (u8 *) elems->mic + elems->mic_len;
+ if ((int) elems_len < ampe_buf - start)
+ return -1;
+
+ crypt_len = elems_len - (elems->mic - start);
+ if (crypt_len < 2 + AES_BLOCK_SIZE) {
+ wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: missing ampe ie");
+ return -1;
+ }
+
+ /* crypt is modified by siv_decrypt */
+ crypt = os_zalloc(crypt_len);
+ if (!crypt) {
+ wpa_printf(MSG_ERROR, "Mesh RSN: out of memory");
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ os_memcpy(crypt, elems->mic, crypt_len);
+
+ if (aes_siv_decrypt(sta->aek, crypt, crypt_len, 3,
+ aad, aad_len, ampe_buf)) {
+ wpa_printf(MSG_ERROR, "Mesh RSN: frame verification failed!");
+ ret = -2;
+ goto free;
+ }
+
+ crypt_len -= AES_BLOCK_SIZE;
+ wpa_hexdump_key(MSG_DEBUG, "mesh: Decrypted AMPE element",
+ ampe_buf, crypt_len);
+
+ ampe_eid = *ampe_buf++;
+ ampe_ie_len = *ampe_buf++;
+
+ if (ampe_eid != WLAN_EID_AMPE ||
+ (size_t) 2 + ampe_ie_len > crypt_len ||
+ ampe_ie_len < sizeof(struct ieee80211_ampe_ie)) {
+ wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: invalid ampe ie");
+ ret = -1;
+ goto free;
+ }
+
+ ampe = (struct ieee80211_ampe_ie *) ampe_buf;
+ pos = (u8 *) (ampe + 1);
+ end = ampe_buf + ampe_ie_len;
+ if (os_memcmp(ampe->peer_nonce, null_nonce, WPA_NONCE_LEN) != 0 &&
+ os_memcmp(ampe->peer_nonce, sta->my_nonce, WPA_NONCE_LEN) != 0) {
+ wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: invalid peer nonce");
+ ret = -1;
+ goto free;
+ }
+ os_memcpy(sta->peer_nonce, ampe->local_nonce,
+ sizeof(ampe->local_nonce));
+
+ /* TODO: Key Replay Counter[8] in Mesh Group Key Inform/Acknowledge
+ * frames */
+
+ /*
+ * GTKdata shall not be included in Mesh Peering Confirm. While the
+ * standard does not state the same about IGTKdata, that same constraint
+ * needs to apply for it. It makes no sense to include the keys in Mesh
+ * Peering Close frames either, so while the standard does not seem to
+ * have a shall statement for these, they are described without
+ * mentioning GTKdata.
+ *
+ * An earlier implementation used to add GTKdata to both Mesh Peering
+ * Open and Mesh Peering Confirm frames, so ignore the possibly present
+ * GTKdata frame without rejecting the frame as a backwards
+ * compatibility mechanism.
+ */
+ if (cat[1] != PLINK_OPEN) {
+ if (end > pos) {
+ wpa_hexdump_key(MSG_DEBUG,
+ "mesh: Ignore unexpected GTKdata(etc.) fields in the end of AMPE element in Mesh Peering Confirm/Close",
+ pos, end - pos);
+ }
+ goto free;
+ }
+
+ /*
+ * GTKdata[variable]:
+ * MGTK[variable] || Key RSC[8] || GTKExpirationTime[4]
+ */
+ sta->mgtk_key_id = 1; /* FIX: Where to get Key ID? */
+ key_len = wpa_cipher_key_len(wpa_s->mesh_rsn->group_cipher);
+ if ((int) key_len + WPA_KEY_RSC_LEN + 4 > end - pos) {
+ wpa_dbg(wpa_s, MSG_DEBUG, "mesh: Truncated AMPE element");
+ ret = -1;
+ goto free;
+ }
+ sta->mgtk_len = key_len;
+ os_memcpy(sta->mgtk, pos, sta->mgtk_len);
+ wpa_hexdump_key(MSG_DEBUG, "mesh: GTKdata - MGTK",
+ sta->mgtk, sta->mgtk_len);
+ pos += sta->mgtk_len;
+ wpa_hexdump(MSG_DEBUG, "mesh: GTKdata - MGTK - Key RSC",
+ pos, WPA_KEY_RSC_LEN);
+ os_memcpy(sta->mgtk_rsc, pos, sizeof(sta->mgtk_rsc));
+ pos += WPA_KEY_RSC_LEN;
+ wpa_printf(MSG_DEBUG,
+ "mesh: GTKdata - MGTK - GTKExpirationTime: %u seconds",
+ WPA_GET_LE32(pos));
+ pos += 4;
+
+#ifdef CONFIG_IEEE80211W
+ /*
+ * IGTKdata[variable]:
+ * Key ID[2], IPN[6], IGTK[variable]
+ */
+ key_len = wpa_cipher_key_len(wpa_s->mesh_rsn->mgmt_group_cipher);
+ if (end - pos >= (int) (2 + 6 + key_len)) {
+ sta->igtk_key_id = WPA_GET_LE16(pos);
+ wpa_printf(MSG_DEBUG, "mesh: IGTKdata - Key ID %u",
+ sta->igtk_key_id);
+ pos += 2;
+ os_memcpy(sta->igtk_rsc, pos, sizeof(sta->igtk_rsc));
+ wpa_hexdump(MSG_DEBUG, "mesh: IGTKdata - IPN",
+ sta->igtk_rsc, sizeof(sta->igtk_rsc));
+ pos += 6;
+ os_memcpy(sta->igtk, pos, key_len);
+ sta->igtk_len = key_len;
+ wpa_hexdump_key(MSG_DEBUG, "mesh: IGTKdata - IGTK",
+ sta->igtk, sta->igtk_len);
+ }
+#endif /* CONFIG_IEEE80211W */
+
+free:
+ os_free(crypt);
+ return ret;
+}
projects / mech_eap.git / blobdiff