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-rw-r--r--contrib/wpa_supplicant/preauth.c934
1 files changed, 934 insertions, 0 deletions
diff --git a/contrib/wpa_supplicant/preauth.c b/contrib/wpa_supplicant/preauth.c
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index 0000000..74a4b0c
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+++ b/contrib/wpa_supplicant/preauth.c
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+/*
+ * WPA Supplicant - RSN pre-authentication and PMKSA caching
+ * Copyright (c) 2003-2006, Jouni Malinen <jkmaline@cc.hut.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/time.h>
+#ifndef CONFIG_NATIVE_WINDOWS
+#include <netinet/in.h>
+#endif /* CONFIG_NATIVE_WINDOWS */
+#include <string.h>
+#include <time.h>
+
+#include "common.h"
+#include "sha1.h"
+#include "wpa.h"
+#include "driver.h"
+#include "eloop.h"
+#include "wpa_supplicant.h"
+#include "config.h"
+#include "l2_packet.h"
+#include "eapol_sm.h"
+#include "preauth.h"
+#include "wpa_i.h"
+
+
+#define PMKID_CANDIDATE_PRIO_SCAN 1000
+static const int pmksa_cache_max_entries = 32;
+
+
+struct rsn_pmksa_candidate {
+ struct rsn_pmksa_candidate *next;
+ u8 bssid[ETH_ALEN];
+ int priority;
+};
+
+
+/**
+ * rsn_pmkid - Calculate PMK identifier
+ * @pmk: Pairwise master key
+ * @aa: Authenticator address
+ * @spa: Supplicant address
+ *
+ * IEEE Std 802.11i-2004 - 8.5.1.2 Pairwise key hierarchy
+ * PMKID = HMAC-SHA1-128(PMK, "PMK Name" || AA || SPA)
+ */
+static void rsn_pmkid(const u8 *pmk, const u8 *aa, const u8 *spa, u8 *pmkid)
+{
+ char *title = "PMK Name";
+ const unsigned char *addr[3];
+ const size_t len[3] = { 8, ETH_ALEN, ETH_ALEN };
+ unsigned char hash[SHA1_MAC_LEN];
+
+ addr[0] = (unsigned char *) title;
+ addr[1] = aa;
+ addr[2] = spa;
+
+ hmac_sha1_vector(pmk, PMK_LEN, 3, addr, len, hash);
+ memcpy(pmkid, hash, PMKID_LEN);
+}
+
+
+static void pmksa_cache_set_expiration(struct wpa_sm *sm);
+
+
+static void pmksa_cache_free_entry(struct wpa_sm *sm,
+ struct rsn_pmksa_cache *entry, int replace)
+{
+ int current;
+
+ current = sm->cur_pmksa == entry ||
+ (sm->pmk_len == entry->pmk_len &&
+ memcmp(sm->pmk, entry->pmk, sm->pmk_len) == 0);
+
+ free(entry);
+ sm->pmksa_count--;
+
+ if (current) {
+ wpa_printf(MSG_DEBUG, "RSN: removed current PMKSA entry");
+ sm->cur_pmksa = NULL;
+
+ if (replace) {
+ /* A new entry is being added, so no need to
+ * deauthenticate in this case. This happens when EAP
+ * authentication is completed again (reauth or failed
+ * PMKSA caching attempt). */
+ return;
+ }
+
+ memset(sm->pmk, 0, sizeof(sm->pmk));
+ wpa_sm_deauthenticate(sm, REASON_UNSPECIFIED);
+ wpa_sm_req_scan(sm, 0, 0);
+ }
+}
+
+
+static void pmksa_cache_expire(void *eloop_ctx, void *timeout_ctx)
+{
+ struct wpa_sm *sm = eloop_ctx;
+ time_t now;
+
+ time(&now);
+ while (sm->pmksa && sm->pmksa->expiration <= now) {
+ struct rsn_pmksa_cache *entry = sm->pmksa;
+ sm->pmksa = entry->next;
+ wpa_printf(MSG_DEBUG, "RSN: expired PMKSA cache entry for "
+ MACSTR, MAC2STR(entry->aa));
+ pmksa_cache_free_entry(sm, entry, 0);
+ }
+
+ pmksa_cache_set_expiration(sm);
+}
+
+
+static void pmksa_cache_reauth(void *eloop_ctx, void *timeout_ctx)
+{
+ struct wpa_sm *sm = eloop_ctx;
+ sm->cur_pmksa = NULL;
+ eapol_sm_request_reauth(sm->eapol);
+}
+
+
+static void pmksa_cache_set_expiration(struct wpa_sm *sm)
+{
+ int sec;
+ struct rsn_pmksa_cache *entry;
+
+ eloop_cancel_timeout(pmksa_cache_expire, sm, NULL);
+ eloop_cancel_timeout(pmksa_cache_reauth, sm, NULL);
+ if (sm->pmksa == NULL)
+ return;
+ sec = sm->pmksa->expiration - time(NULL);
+ if (sec < 0)
+ sec = 0;
+ eloop_register_timeout(sec + 1, 0, pmksa_cache_expire, sm, NULL);
+
+ entry = sm->cur_pmksa ? sm->cur_pmksa :
+ pmksa_cache_get(sm, sm->bssid, NULL);
+ if (entry) {
+ sec = sm->pmksa->reauth_time - time(NULL);
+ if (sec < 0)
+ sec = 0;
+ eloop_register_timeout(sec, 0, pmksa_cache_reauth, sm, NULL);
+ }
+}
+
+
+/**
+ * pmksa_cache_add - Add a PMKSA cache entry
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * @pmk: The new pairwise master key
+ * @pmk_len: PMK length in bytes, usually PMK_LEN (32)
+ * @aa: Authenticator address
+ * @spa: Supplicant address
+ * @ssid: The network configuration for which this PMK is being added
+ * Returns: Pointer to the added PMKSA cache entry or %NULL on error
+ *
+ * This function create a PMKSA entry for a new PMK and adds it to the PMKSA
+ * cache. If an old entry is already in the cache for the same Authenticator,
+ * this entry will be replaced with the new entry. PMKID will be calculated
+ * based on the PMK and the driver interface is notified of the new PMKID.
+ */
+struct rsn_pmksa_cache *
+pmksa_cache_add(struct wpa_sm *sm, const u8 *pmk,
+ size_t pmk_len, const u8 *aa, const u8 *spa,
+ struct wpa_ssid *ssid)
+{
+ struct rsn_pmksa_cache *entry, *pos, *prev;
+ time_t now;
+
+ if (sm->proto != WPA_PROTO_RSN || pmk_len > PMK_LEN)
+ return NULL;
+
+ entry = malloc(sizeof(*entry));
+ if (entry == NULL)
+ return NULL;
+ memset(entry, 0, sizeof(*entry));
+ memcpy(entry->pmk, pmk, pmk_len);
+ entry->pmk_len = pmk_len;
+ rsn_pmkid(pmk, aa, spa, entry->pmkid);
+ now = time(NULL);
+ entry->expiration = now + sm->dot11RSNAConfigPMKLifetime;
+ entry->reauth_time = now + sm->dot11RSNAConfigPMKLifetime *
+ sm->dot11RSNAConfigPMKReauthThreshold / 100;
+ entry->akmp = WPA_KEY_MGMT_IEEE8021X;
+ memcpy(entry->aa, aa, ETH_ALEN);
+ entry->ssid = ssid;
+
+ /* Replace an old entry for the same Authenticator (if found) with the
+ * new entry */
+ pos = sm->pmksa;
+ prev = NULL;
+ while (pos) {
+ if (memcmp(aa, pos->aa, ETH_ALEN) == 0) {
+ if (pos->pmk_len == pmk_len &&
+ memcmp(pos->pmk, pmk, pmk_len) == 0 &&
+ memcmp(pos->pmkid, entry->pmkid, PMKID_LEN) == 0) {
+ wpa_printf(MSG_DEBUG, "WPA: reusing previous "
+ "PMKSA entry");
+ free(entry);
+ return pos;
+ }
+ if (prev == NULL)
+ sm->pmksa = pos->next;
+ else
+ prev->next = pos->next;
+ wpa_printf(MSG_DEBUG, "RSN: Replace PMKSA entry for "
+ "the current AP");
+ pmksa_cache_free_entry(sm, pos, 1);
+ break;
+ }
+ prev = pos;
+ pos = pos->next;
+ }
+
+ if (sm->pmksa_count >= pmksa_cache_max_entries && sm->pmksa) {
+ /* Remove the oldest entry to make room for the new entry */
+ pos = sm->pmksa;
+ sm->pmksa = pos->next;
+ wpa_printf(MSG_DEBUG, "RSN: removed the oldest PMKSA cache "
+ "entry (for " MACSTR ") to make room for new one",
+ MAC2STR(pos->aa));
+ wpa_sm_remove_pmkid(sm, pos->aa, pos->pmkid);
+ pmksa_cache_free_entry(sm, pos, 0);
+ }
+
+ /* Add the new entry; order by expiration time */
+ pos = sm->pmksa;
+ prev = NULL;
+ while (pos) {
+ if (pos->expiration > entry->expiration)
+ break;
+ prev = pos;
+ pos = pos->next;
+ }
+ if (prev == NULL) {
+ entry->next = sm->pmksa;
+ sm->pmksa = entry;
+ pmksa_cache_set_expiration(sm);
+ } else {
+ entry->next = prev->next;
+ prev->next = entry;
+ }
+ sm->pmksa_count++;
+ wpa_printf(MSG_DEBUG, "RSN: added PMKSA cache entry for " MACSTR,
+ MAC2STR(entry->aa));
+ wpa_sm_add_pmkid(sm, entry->aa, entry->pmkid);
+
+ return entry;
+}
+
+
+/**
+ * pmksa_cache_free - Free all entries in PMKSA cache
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ */
+void pmksa_cache_free(struct wpa_sm *sm)
+{
+ struct rsn_pmksa_cache *entry, *prev;
+
+ if (sm == NULL)
+ return;
+
+ entry = sm->pmksa;
+ sm->pmksa = NULL;
+ while (entry) {
+ prev = entry;
+ entry = entry->next;
+ free(prev);
+ }
+ pmksa_cache_set_expiration(sm);
+ sm->cur_pmksa = NULL;
+}
+
+
+/**
+ * pmksa_cache_get - Fetch a PMKSA cache entry
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * @aa: Authenticator address or %NULL to match any
+ * @pmkid: PMKID or %NULL to match any
+ * Returns: Pointer to PMKSA cache entry or %NULL if no match was found
+ */
+struct rsn_pmksa_cache * pmksa_cache_get(struct wpa_sm *sm,
+ const u8 *aa, const u8 *pmkid)
+{
+ struct rsn_pmksa_cache *entry = sm->pmksa;
+ while (entry) {
+ if ((aa == NULL || memcmp(entry->aa, aa, ETH_ALEN) == 0) &&
+ (pmkid == NULL ||
+ memcmp(entry->pmkid, pmkid, PMKID_LEN) == 0))
+ return entry;
+ entry = entry->next;
+ }
+ return NULL;
+}
+
+
+/**
+ * pmksa_cache_notify_reconfig - Reconfiguration notification for PMKSA cache
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ *
+ * Clear references to old data structures when wpa_supplicant is reconfigured.
+ */
+void pmksa_cache_notify_reconfig(struct wpa_sm *sm)
+{
+ struct rsn_pmksa_cache *entry = sm->pmksa;
+ while (entry) {
+ entry->ssid = NULL;
+ entry = entry->next;
+ }
+}
+
+
+static struct rsn_pmksa_cache *
+pmksa_cache_clone_entry(struct wpa_sm *sm,
+ const struct rsn_pmksa_cache *old_entry, const u8 *aa)
+{
+ struct rsn_pmksa_cache *new_entry;
+
+ new_entry = pmksa_cache_add(sm, old_entry->pmk, old_entry->pmk_len,
+ aa, sm->own_addr, old_entry->ssid);
+ if (new_entry == NULL)
+ return NULL;
+
+ /* TODO: reorder entries based on expiration time? */
+ new_entry->expiration = old_entry->expiration;
+ new_entry->opportunistic = 1;
+
+ return new_entry;
+}
+
+
+/**
+ * pmksa_cache_get_opportunistic - Try to get an opportunistic PMKSA entry
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * @ssid: Pointer to the current network configuration
+ * @aa: Authenticator address for the new AP
+ * Returns: Pointer to a new PMKSA cache entry or %NULL if not available
+ *
+ * Try to create a new PMKSA cache entry opportunistically by guessing that the
+ * new AP is sharing the same PMK as another AP that has the same SSID and has
+ * already an entry in PMKSA cache.
+ */
+static struct rsn_pmksa_cache *
+pmksa_cache_get_opportunistic(struct wpa_sm *sm,
+ struct wpa_ssid *ssid, const u8 *aa)
+{
+ struct rsn_pmksa_cache *entry = sm->pmksa;
+
+ if (ssid == NULL)
+ return NULL;
+ while (entry) {
+ if (entry->ssid == ssid) {
+ entry = pmksa_cache_clone_entry(sm, entry, aa);
+ if (entry) {
+ wpa_printf(MSG_DEBUG, "RSN: added "
+ "opportunistic PMKSA cache entry "
+ "for " MACSTR, MAC2STR(aa));
+ }
+ return entry;
+ }
+ entry = entry->next;
+ }
+ return NULL;
+}
+
+
+/**
+ * pmksa_cache_get_current - Get the current used PMKSA entry
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * Returns: Pointer to the current PMKSA cache entry or %NULL if not available
+ */
+struct rsn_pmksa_cache * pmksa_cache_get_current(struct wpa_sm *sm)
+{
+ if (sm == NULL)
+ return NULL;
+ return sm->cur_pmksa;
+}
+
+
+/**
+ * pmksa_cache_clear_current - Clear the current PMKSA entry selection
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ */
+void pmksa_cache_clear_current(struct wpa_sm *sm)
+{
+ if (sm == NULL)
+ return;
+ sm->cur_pmksa = NULL;
+}
+
+
+/**
+ * pmksa_cache_set_current - Set the current PMKSA entry selection
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * @pmkid: PMKID for selecting PMKSA or %NULL if not used
+ * @bssid: BSSID for PMKSA or %NULL if not used
+ * @ssid: The network configuration for the current network
+ * @try_opportunistic: Whether to allow opportunistic PMKSA caching
+ * Returns: 0 if PMKSA was found or -1 if no matching entry was found
+ */
+int pmksa_cache_set_current(struct wpa_sm *sm, const u8 *pmkid,
+ const u8 *bssid, struct wpa_ssid *ssid,
+ int try_opportunistic)
+{
+ sm->cur_pmksa = NULL;
+ if (pmkid)
+ sm->cur_pmksa = pmksa_cache_get(sm, NULL, pmkid);
+ if (sm->cur_pmksa == NULL && bssid)
+ sm->cur_pmksa = pmksa_cache_get(sm, bssid, NULL);
+ if (sm->cur_pmksa == NULL && try_opportunistic)
+ sm->cur_pmksa = pmksa_cache_get_opportunistic(sm, ssid, bssid);
+ if (sm->cur_pmksa) {
+ wpa_hexdump(MSG_DEBUG, "RSN: PMKID",
+ sm->cur_pmksa->pmkid, PMKID_LEN);
+ return 0;
+ }
+ return -1;
+}
+
+
+/**
+ * pmksa_cache_list - Dump text list of entries in PMKSA cache
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * @buf: Buffer for the list
+ * @len: Length of the buffer
+ * Returns: number of bytes written to buffer
+ *
+ * This function is used to generate a text format representation of the
+ * current PMKSA cache contents for the ctrl_iface PMKSA command.
+ */
+int pmksa_cache_list(struct wpa_sm *sm, char *buf, size_t len)
+{
+ int i, j;
+ char *pos = buf;
+ struct rsn_pmksa_cache *entry;
+ time_t now;
+
+ time(&now);
+ pos += snprintf(pos, buf + len - pos,
+ "Index / AA / PMKID / expiration (in seconds) / "
+ "opportunistic\n");
+ i = 0;
+ entry = sm->pmksa;
+ while (entry) {
+ i++;
+ pos += snprintf(pos, buf + len - pos, "%d " MACSTR " ",
+ i, MAC2STR(entry->aa));
+ for (j = 0; j < PMKID_LEN; j++)
+ pos += snprintf(pos, buf + len - pos, "%02x",
+ entry->pmkid[j]);
+ pos += snprintf(pos, buf + len - pos, " %d %d\n",
+ (int) (entry->expiration - now),
+ entry->opportunistic);
+ entry = entry->next;
+ }
+ return pos - buf;
+}
+
+
+/**
+ * pmksa_candidate_free - Free all entries in PMKSA candidate list
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ */
+void pmksa_candidate_free(struct wpa_sm *sm)
+{
+ struct rsn_pmksa_candidate *entry, *prev;
+
+ if (sm == NULL)
+ return;
+
+ entry = sm->pmksa_candidates;
+ sm->pmksa_candidates = NULL;
+ while (entry) {
+ prev = entry;
+ entry = entry->next;
+ free(prev);
+ }
+}
+
+
+#ifdef IEEE8021X_EAPOL
+
+static void rsn_preauth_receive(void *ctx, const u8 *src_addr,
+ const u8 *buf, size_t len)
+{
+ struct wpa_sm *sm = ctx;
+
+ wpa_printf(MSG_DEBUG, "RX pre-auth from " MACSTR, MAC2STR(src_addr));
+ wpa_hexdump(MSG_MSGDUMP, "RX pre-auth", buf, len);
+
+ if (sm->preauth_eapol == NULL ||
+ memcmp(sm->preauth_bssid, "\x00\x00\x00\x00\x00\x00",
+ ETH_ALEN) == 0 ||
+ memcmp(sm->preauth_bssid, src_addr, ETH_ALEN) != 0) {
+ wpa_printf(MSG_WARNING, "RSN pre-auth frame received from "
+ "unexpected source " MACSTR " - dropped",
+ MAC2STR(src_addr));
+ return;
+ }
+
+ eapol_sm_rx_eapol(sm->preauth_eapol, src_addr, buf, len);
+}
+
+
+static void rsn_preauth_eapol_cb(struct eapol_sm *eapol, int success,
+ void *ctx)
+{
+ struct wpa_sm *sm = ctx;
+ u8 pmk[PMK_LEN];
+
+ if (success) {
+ int res, pmk_len;
+ pmk_len = PMK_LEN;
+ res = eapol_sm_get_key(eapol, pmk, PMK_LEN);
+#ifdef EAP_LEAP
+ if (res) {
+ res = eapol_sm_get_key(eapol, pmk, 16);
+ pmk_len = 16;
+ }
+#endif /* EAP_LEAP */
+ if (res == 0) {
+ wpa_hexdump_key(MSG_DEBUG, "RSN: PMK from pre-auth",
+ pmk, pmk_len);
+ sm->pmk_len = pmk_len;
+ pmksa_cache_add(sm, pmk, pmk_len,
+ sm->preauth_bssid, sm->own_addr,
+ sm->cur_ssid);
+ } else {
+ wpa_msg(sm->ctx->ctx, MSG_INFO, "RSN: failed to get "
+ "master session key from pre-auth EAPOL state "
+ "machines");
+ success = 0;
+ }
+ }
+
+ wpa_msg(sm->ctx->ctx, MSG_INFO, "RSN: pre-authentication with " MACSTR
+ " %s", MAC2STR(sm->preauth_bssid),
+ success ? "completed successfully" : "failed");
+
+ rsn_preauth_deinit(sm);
+ rsn_preauth_candidate_process(sm);
+}
+
+
+static void rsn_preauth_timeout(void *eloop_ctx, void *timeout_ctx)
+{
+ struct wpa_sm *sm = eloop_ctx;
+
+ wpa_msg(sm->ctx->ctx, MSG_INFO, "RSN: pre-authentication with " MACSTR
+ " timed out", MAC2STR(sm->preauth_bssid));
+ rsn_preauth_deinit(sm);
+ rsn_preauth_candidate_process(sm);
+}
+
+
+static int rsn_preauth_eapol_send(void *ctx, int type, const u8 *buf,
+ size_t len)
+{
+ struct wpa_sm *sm = ctx;
+ u8 *msg;
+ size_t msglen;
+ int res;
+
+ /* TODO: could add l2_packet_sendmsg that allows fragments to avoid
+ * extra copy here */
+
+ if (sm->l2_preauth == NULL)
+ return -1;
+
+ msg = wpa_sm_alloc_eapol(sm, type, buf, len, &msglen, NULL);
+ if (msg == NULL)
+ return -1;
+
+ wpa_hexdump(MSG_MSGDUMP, "TX EAPOL (preauth)", msg, msglen);
+ res = l2_packet_send(sm->l2_preauth, sm->preauth_bssid,
+ ETH_P_RSN_PREAUTH, msg, msglen);
+ free(msg);
+ return res;
+}
+
+
+/**
+ * rsn_preauth_init - Start new RSN pre-authentication
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * @dst: Authenticator address (BSSID) with which to preauthenticate
+ * @config: Current network configuration
+ * Returns: 0 on success, -1 on another pre-authentication is in progress,
+ * -2 on layer 2 packet initialization failure, -3 on EAPOL state machine
+ * initialization failure, -4 on memory allocation failure
+ *
+ * This function request an RSN pre-authentication with a given destination
+ * address. This is usually called for PMKSA candidates found from scan results
+ * or from driver reports. In addition, ctrl_iface PREAUTH command can trigger
+ * pre-authentication.
+ */
+int rsn_preauth_init(struct wpa_sm *sm, const u8 *dst, struct wpa_ssid *config)
+{
+ struct eapol_config eapol_conf;
+ struct eapol_ctx *ctx;
+
+ if (sm->preauth_eapol)
+ return -1;
+
+ wpa_msg(sm->ctx->ctx, MSG_DEBUG, "RSN: starting pre-authentication "
+ "with " MACSTR, MAC2STR(dst));
+
+ sm->l2_preauth = l2_packet_init(sm->ifname, sm->own_addr,
+ ETH_P_RSN_PREAUTH,
+ rsn_preauth_receive, sm, 0);
+ if (sm->l2_preauth == NULL) {
+ wpa_printf(MSG_WARNING, "RSN: Failed to initialize L2 packet "
+ "processing for pre-authentication");
+ return -2;
+ }
+
+ ctx = malloc(sizeof(*ctx));
+ if (ctx == NULL) {
+ wpa_printf(MSG_WARNING, "Failed to allocate EAPOL context.");
+ return -4;
+ }
+ memset(ctx, 0, sizeof(*ctx));
+ ctx->ctx = sm->ctx->ctx;
+ ctx->msg_ctx = sm->ctx->ctx;
+ ctx->preauth = 1;
+ ctx->cb = rsn_preauth_eapol_cb;
+ ctx->cb_ctx = sm;
+ ctx->scard_ctx = sm->scard_ctx;
+ ctx->eapol_send = rsn_preauth_eapol_send;
+ ctx->eapol_send_ctx = sm;
+ ctx->set_config_blob = sm->ctx->set_config_blob;
+ ctx->get_config_blob = sm->ctx->get_config_blob;
+
+ sm->preauth_eapol = eapol_sm_init(ctx);
+ if (sm->preauth_eapol == NULL) {
+ free(ctx);
+ wpa_printf(MSG_WARNING, "RSN: Failed to initialize EAPOL "
+ "state machines for pre-authentication");
+ return -3;
+ }
+ memset(&eapol_conf, 0, sizeof(eapol_conf));
+ eapol_conf.accept_802_1x_keys = 0;
+ eapol_conf.required_keys = 0;
+ eapol_conf.fast_reauth = sm->fast_reauth;
+ if (config)
+ eapol_conf.workaround = config->eap_workaround;
+ eapol_sm_notify_config(sm->preauth_eapol, config, &eapol_conf);
+ /*
+ * Use a shorter startPeriod with preauthentication since the first
+ * preauth EAPOL-Start frame may end up being dropped due to race
+ * condition in the AP between the data receive and key configuration
+ * after the 4-Way Handshake.
+ */
+ eapol_sm_configure(sm->preauth_eapol, -1, -1, 5, 6);
+ memcpy(sm->preauth_bssid, dst, ETH_ALEN);
+
+ eapol_sm_notify_portValid(sm->preauth_eapol, TRUE);
+ /* 802.1X::portControl = Auto */
+ eapol_sm_notify_portEnabled(sm->preauth_eapol, TRUE);
+
+ eloop_register_timeout(sm->dot11RSNAConfigSATimeout, 0,
+ rsn_preauth_timeout, sm, NULL);
+
+ return 0;
+}
+
+
+/**
+ * rsn_preauth_deinit - Abort RSN pre-authentication
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ *
+ * This function aborts the current RSN pre-authentication (if one is started)
+ * and frees resources allocated for it.
+ */
+void rsn_preauth_deinit(struct wpa_sm *sm)
+{
+ if (sm == NULL || !sm->preauth_eapol)
+ return;
+
+ eloop_cancel_timeout(rsn_preauth_timeout, sm, NULL);
+ eapol_sm_deinit(sm->preauth_eapol);
+ sm->preauth_eapol = NULL;
+ memset(sm->preauth_bssid, 0, ETH_ALEN);
+
+ l2_packet_deinit(sm->l2_preauth);
+ sm->l2_preauth = NULL;
+}
+
+
+/**
+ * rsn_preauth_candidate_process - Process PMKSA candidates
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ *
+ * Go through the PMKSA candidates and start pre-authentication if a candidate
+ * without an existing PMKSA cache entry is found. Processed candidates will be
+ * removed from the list.
+ */
+void rsn_preauth_candidate_process(struct wpa_sm *sm)
+{
+ struct rsn_pmksa_candidate *candidate;
+
+ if (sm->pmksa_candidates == NULL)
+ return;
+
+ /* TODO: drop priority for old candidate entries */
+
+ wpa_msg(sm->ctx->ctx, MSG_DEBUG, "RSN: processing PMKSA candidate "
+ "list");
+ if (sm->preauth_eapol ||
+ sm->proto != WPA_PROTO_RSN ||
+ wpa_sm_get_state(sm) != WPA_COMPLETED ||
+ sm->key_mgmt != WPA_KEY_MGMT_IEEE8021X) {
+ wpa_msg(sm->ctx->ctx, MSG_DEBUG, "RSN: not in suitable state "
+ "for new pre-authentication");
+ return; /* invalid state for new pre-auth */
+ }
+
+ while (sm->pmksa_candidates) {
+ struct rsn_pmksa_cache *p = NULL;
+ candidate = sm->pmksa_candidates;
+ p = pmksa_cache_get(sm, candidate->bssid, NULL);
+ if (memcmp(sm->bssid, candidate->bssid, ETH_ALEN) != 0 &&
+ (p == NULL || p->opportunistic)) {
+ wpa_msg(sm->ctx->ctx, MSG_DEBUG, "RSN: PMKSA "
+ "candidate " MACSTR
+ " selected for pre-authentication",
+ MAC2STR(candidate->bssid));
+ sm->pmksa_candidates = candidate->next;
+ rsn_preauth_init(sm, candidate->bssid, sm->cur_ssid);
+ free(candidate);
+ return;
+ }
+ wpa_msg(sm->ctx->ctx, MSG_DEBUG, "RSN: PMKSA candidate "
+ MACSTR " does not need pre-authentication anymore",
+ MAC2STR(candidate->bssid));
+ /* Some drivers (e.g., NDIS) expect to get notified about the
+ * PMKIDs again, so report the existing data now. */
+ if (p) {
+ wpa_sm_add_pmkid(sm, candidate->bssid, p->pmkid);
+ }
+
+ sm->pmksa_candidates = candidate->next;
+ free(candidate);
+ }
+ wpa_msg(sm->ctx->ctx, MSG_DEBUG, "RSN: no more pending PMKSA "
+ "candidates");
+}
+
+
+/**
+ * pmksa_candidate_add - Add a new PMKSA candidate
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * @bssid: BSSID (authenticator address) of the candidate
+ * @prio: Priority (the smaller number, the higher priority)
+ * @preauth: Whether the candidate AP advertises support for pre-authentication
+ *
+ * This function is used to add PMKSA candidates for RSN pre-authentication. It
+ * is called from scan result processing and from driver events for PMKSA
+ * candidates, i.e., EVENT_PMKID_CANDIDATE events to wpa_supplicant_event().
+ */
+void pmksa_candidate_add(struct wpa_sm *sm, const u8 *bssid,
+ int prio, int preauth)
+{
+ struct rsn_pmksa_candidate *cand, *prev, *pos;
+
+ if (sm->cur_ssid && sm->cur_ssid->proactive_key_caching)
+ pmksa_cache_get_opportunistic(sm, sm->cur_ssid, bssid);
+
+ if (!preauth) {
+ wpa_printf(MSG_DEBUG, "RSN: Ignored PMKID candidate without "
+ "preauth flag");
+ return;
+ }
+
+ /* If BSSID already on candidate list, update the priority of the old
+ * entry. Do not override priority based on normal scan results. */
+ prev = NULL;
+ cand = sm->pmksa_candidates;
+ while (cand) {
+ if (memcmp(cand->bssid, bssid, ETH_ALEN) == 0) {
+ if (prev)
+ prev->next = cand->next;
+ else
+ sm->pmksa_candidates = cand->next;
+ break;
+ }
+ prev = cand;
+ cand = cand->next;
+ }
+
+ if (cand) {
+ if (prio < PMKID_CANDIDATE_PRIO_SCAN)
+ cand->priority = prio;
+ } else {
+ cand = malloc(sizeof(*cand));
+ if (cand == NULL)
+ return;
+ memset(cand, 0, sizeof(*cand));
+ memcpy(cand->bssid, bssid, ETH_ALEN);
+ cand->priority = prio;
+ }
+
+ /* Add candidate to the list; order by increasing priority value. i.e.,
+ * highest priority (smallest value) first. */
+ prev = NULL;
+ pos = sm->pmksa_candidates;
+ while (pos) {
+ if (cand->priority <= pos->priority)
+ break;
+ prev = pos;
+ pos = pos->next;
+ }
+ cand->next = pos;
+ if (prev)
+ prev->next = cand;
+ else
+ sm->pmksa_candidates = cand;
+
+ wpa_msg(sm->ctx->ctx, MSG_DEBUG, "RSN: added PMKSA cache "
+ "candidate " MACSTR " prio %d", MAC2STR(bssid), prio);
+ rsn_preauth_candidate_process(sm);
+}
+
+
+/* TODO: schedule periodic scans if current AP supports preauth */
+
+/**
+ * rsn_preauth_scan_results - Process scan results to find PMKSA candidates
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * @results: Scan results
+ * @count: Number of BSSes in scan results
+ *
+ * This functions goes through the scan results and adds all suitable APs
+ * (Authenticators) into PMKSA candidate list.
+ */
+void rsn_preauth_scan_results(struct wpa_sm *sm,
+ struct wpa_scan_result *results, int count)
+{
+ struct wpa_scan_result *r;
+ struct wpa_ie_data ie;
+ int i;
+ struct rsn_pmksa_cache *pmksa;
+
+ if (sm->cur_ssid == NULL)
+ return;
+
+ /*
+ * TODO: is it ok to free all candidates? What about the entries
+ * received from EVENT_PMKID_CANDIDATE?
+ */
+ pmksa_candidate_free(sm);
+
+ for (i = count - 1; i >= 0; i--) {
+ r = &results[i];
+ if (r->ssid_len != sm->cur_ssid->ssid_len ||
+ memcmp(r->ssid, sm->cur_ssid->ssid,
+ r->ssid_len) != 0)
+ continue;
+
+ if (memcmp(r->bssid, sm->bssid, ETH_ALEN) == 0)
+ continue;
+
+ if (r->rsn_ie_len == 0 ||
+ wpa_parse_wpa_ie(r->rsn_ie, r->rsn_ie_len, &ie))
+ continue;
+
+ pmksa = pmksa_cache_get(sm, r->bssid, NULL);
+ if (pmksa &&
+ (!pmksa->opportunistic ||
+ !(ie.capabilities & WPA_CAPABILITY_PREAUTH)))
+ continue;
+
+ /*
+ * Give less priority to candidates found from normal
+ * scan results.
+ */
+ pmksa_candidate_add(sm, r->bssid,
+ PMKID_CANDIDATE_PRIO_SCAN,
+ ie.capabilities & WPA_CAPABILITY_PREAUTH);
+ }
+}
+
+
+/**
+ * rsn_preauth_get_status - Get pre-authentication status
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ * @buf: Buffer for status information
+ * @buflen: Maximum buffer length
+ * @verbose: Whether to include verbose status information
+ * Returns: Number of bytes written to buf.
+ *
+ * Query WPA2 pre-authentication for status information. This function fills in
+ * a text area with current status information. If the buffer (buf) is not
+ * large enough, status information will be truncated to fit the buffer.
+ */
+int rsn_preauth_get_status(struct wpa_sm *sm, char *buf, size_t buflen,
+ int verbose)
+{
+ char *pos = buf, *end = buf + buflen;
+ int res;
+
+ if (sm->preauth_eapol) {
+ pos += snprintf(pos, end - pos, "Pre-authentication "
+ "EAPOL state machines:\n");
+ res = eapol_sm_get_status(sm->preauth_eapol,
+ pos, end - pos, verbose);
+ if (res >= 0)
+ pos += res;
+ }
+
+ return pos - buf;
+}
+
+
+/**
+ * rsn_preauth_in_progress - Verify whether pre-authentication is in progress
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ */
+int rsn_preauth_in_progress(struct wpa_sm *sm)
+{
+ return sm->preauth_eapol != NULL;
+}
+
+#endif /* IEEE8021X_EAPOL */
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