+++ /dev/null
-/*
- * WPA Supplicant - RSN PMKSA cache
- * Copyright (c) 2004-2008, Jouni Malinen <j@w1.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 "includes.h"
-
-#include "common.h"
-#include "eloop.h"
-#include "eapol_supp/eapol_supp_sm.h"
-#include "wpa.h"
-#include "wpa_i.h"
-#include "pmksa_cache.h"
-
-#if defined(IEEE8021X_EAPOL) && !defined(CONFIG_NO_WPA2)
-
-static const int pmksa_cache_max_entries = 32;
-
-struct rsn_pmksa_cache {
- struct rsn_pmksa_cache_entry *pmksa; /* PMKSA cache */
- int pmksa_count; /* number of entries in PMKSA cache */
- struct wpa_sm *sm; /* TODO: get rid of this reference(?) */
-
- void (*free_cb)(struct rsn_pmksa_cache_entry *entry, void *ctx,
- int replace);
- void *ctx;
-};
-
-
-static void pmksa_cache_set_expiration(struct rsn_pmksa_cache *pmksa);
-
-
-static void _pmksa_cache_free_entry(struct rsn_pmksa_cache_entry *entry)
-{
- os_free(entry);
-}
-
-
-static void pmksa_cache_free_entry(struct rsn_pmksa_cache *pmksa,
- struct rsn_pmksa_cache_entry *entry,
- int replace)
-{
- pmksa->pmksa_count--;
- pmksa->free_cb(entry, pmksa->ctx, replace);
- _pmksa_cache_free_entry(entry);
-}
-
-
-static void pmksa_cache_expire(void *eloop_ctx, void *timeout_ctx)
-{
- struct rsn_pmksa_cache *pmksa = eloop_ctx;
- struct os_time now;
-
- os_get_time(&now);
- while (pmksa->pmksa && pmksa->pmksa->expiration <= now.sec) {
- struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
- pmksa->pmksa = entry->next;
- wpa_printf(MSG_DEBUG, "RSN: expired PMKSA cache entry for "
- MACSTR, MAC2STR(entry->aa));
- pmksa_cache_free_entry(pmksa, entry, 0);
- }
-
- pmksa_cache_set_expiration(pmksa);
-}
-
-
-static void pmksa_cache_reauth(void *eloop_ctx, void *timeout_ctx)
-{
- struct rsn_pmksa_cache *pmksa = eloop_ctx;
- pmksa->sm->cur_pmksa = NULL;
- eapol_sm_request_reauth(pmksa->sm->eapol);
-}
-
-
-static void pmksa_cache_set_expiration(struct rsn_pmksa_cache *pmksa)
-{
- int sec;
- struct rsn_pmksa_cache_entry *entry;
- struct os_time now;
-
- eloop_cancel_timeout(pmksa_cache_expire, pmksa, NULL);
- eloop_cancel_timeout(pmksa_cache_reauth, pmksa, NULL);
- if (pmksa->pmksa == NULL)
- return;
- os_get_time(&now);
- sec = pmksa->pmksa->expiration - now.sec;
- if (sec < 0)
- sec = 0;
- eloop_register_timeout(sec + 1, 0, pmksa_cache_expire, pmksa, NULL);
-
- entry = pmksa->sm->cur_pmksa ? pmksa->sm->cur_pmksa :
- pmksa_cache_get(pmksa, pmksa->sm->bssid, NULL);
- if (entry) {
- sec = pmksa->pmksa->reauth_time - now.sec;
- if (sec < 0)
- sec = 0;
- eloop_register_timeout(sec, 0, pmksa_cache_reauth, pmksa,
- NULL);
- }
-}
-
-
-/**
- * pmksa_cache_add - Add a PMKSA cache entry
- * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
- * @pmk: The new pairwise master key
- * @pmk_len: PMK length in bytes, usually PMK_LEN (32)
- * @aa: Authenticator address
- * @spa: Supplicant address
- * @network_ctx: Network configuration context for this PMK
- * @akmp: WPA_KEY_MGMT_* used in key derivation
- * 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_entry *
-pmksa_cache_add(struct rsn_pmksa_cache *pmksa, const u8 *pmk, size_t pmk_len,
- const u8 *aa, const u8 *spa, void *network_ctx, int akmp)
-{
- struct rsn_pmksa_cache_entry *entry, *pos, *prev;
- struct os_time now;
-
- if (pmk_len > PMK_LEN)
- return NULL;
-
- entry = os_zalloc(sizeof(*entry));
- if (entry == NULL)
- return NULL;
- os_memcpy(entry->pmk, pmk, pmk_len);
- entry->pmk_len = pmk_len;
- rsn_pmkid(pmk, pmk_len, aa, spa, entry->pmkid,
- wpa_key_mgmt_sha256(akmp));
- os_get_time(&now);
- entry->expiration = now.sec + pmksa->sm->dot11RSNAConfigPMKLifetime;
- entry->reauth_time = now.sec + pmksa->sm->dot11RSNAConfigPMKLifetime *
- pmksa->sm->dot11RSNAConfigPMKReauthThreshold / 100;
- entry->akmp = akmp;
- os_memcpy(entry->aa, aa, ETH_ALEN);
- entry->network_ctx = network_ctx;
-
- /* Replace an old entry for the same Authenticator (if found) with the
- * new entry */
- pos = pmksa->pmksa;
- prev = NULL;
- while (pos) {
- if (os_memcmp(aa, pos->aa, ETH_ALEN) == 0) {
- if (pos->pmk_len == pmk_len &&
- os_memcmp(pos->pmk, pmk, pmk_len) == 0 &&
- os_memcmp(pos->pmkid, entry->pmkid, PMKID_LEN) ==
- 0) {
- wpa_printf(MSG_DEBUG, "WPA: reusing previous "
- "PMKSA entry");
- os_free(entry);
- return pos;
- }
- if (prev == NULL)
- pmksa->pmksa = pos->next;
- else
- prev->next = pos->next;
- if (pos == pmksa->sm->cur_pmksa) {
- /* We are about to replace the current PMKSA
- * cache entry. This happens when the PMKSA
- * caching attempt fails, so we don't want to
- * force pmksa_cache_free_entry() to disconnect
- * at this point. Let's just make sure the old
- * PMKSA cache entry will not be used in the
- * future.
- */
- wpa_printf(MSG_DEBUG, "RSN: replacing current "
- "PMKSA entry");
- pmksa->sm->cur_pmksa = NULL;
- }
- wpa_printf(MSG_DEBUG, "RSN: Replace PMKSA entry for "
- "the current AP");
- pmksa_cache_free_entry(pmksa, pos, 1);
- break;
- }
- prev = pos;
- pos = pos->next;
- }
-
- if (pmksa->pmksa_count >= pmksa_cache_max_entries && pmksa->pmksa) {
- /* Remove the oldest entry to make room for the new entry */
- pos = pmksa->pmksa;
- pmksa->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(pmksa->sm, pos->aa, pos->pmkid);
- pmksa_cache_free_entry(pmksa, pos, 0);
- }
-
- /* Add the new entry; order by expiration time */
- pos = pmksa->pmksa;
- prev = NULL;
- while (pos) {
- if (pos->expiration > entry->expiration)
- break;
- prev = pos;
- pos = pos->next;
- }
- if (prev == NULL) {
- entry->next = pmksa->pmksa;
- pmksa->pmksa = entry;
- pmksa_cache_set_expiration(pmksa);
- } else {
- entry->next = prev->next;
- prev->next = entry;
- }
- pmksa->pmksa_count++;
- wpa_printf(MSG_DEBUG, "RSN: added PMKSA cache entry for " MACSTR,
- MAC2STR(entry->aa));
- wpa_sm_add_pmkid(pmksa->sm, entry->aa, entry->pmkid);
-
- return entry;
-}
-
-
-/**
- * pmksa_cache_deinit - Free all entries in PMKSA cache
- * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
- */
-void pmksa_cache_deinit(struct rsn_pmksa_cache *pmksa)
-{
- struct rsn_pmksa_cache_entry *entry, *prev;
-
- if (pmksa == NULL)
- return;
-
- entry = pmksa->pmksa;
- pmksa->pmksa = NULL;
- while (entry) {
- prev = entry;
- entry = entry->next;
- os_free(prev);
- }
- pmksa_cache_set_expiration(pmksa);
- os_free(pmksa);
-}
-
-
-/**
- * pmksa_cache_get - Fetch a PMKSA cache entry
- * @pmksa: Pointer to PMKSA cache data from pmksa_cache_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_entry * pmksa_cache_get(struct rsn_pmksa_cache *pmksa,
- const u8 *aa, const u8 *pmkid)
-{
- struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
- while (entry) {
- if ((aa == NULL || os_memcmp(entry->aa, aa, ETH_ALEN) == 0) &&
- (pmkid == NULL ||
- os_memcmp(entry->pmkid, pmkid, PMKID_LEN) == 0))
- return entry;
- entry = entry->next;
- }
- return NULL;
-}
-
-
-/**
- * pmksa_cache_notify_reconfig - Reconfiguration notification for PMKSA cache
- * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
- *
- * Clear references to old data structures when wpa_supplicant is reconfigured.
- */
-void pmksa_cache_notify_reconfig(struct rsn_pmksa_cache *pmksa)
-{
- struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
- while (entry) {
- entry->network_ctx = NULL;
- entry = entry->next;
- }
-}
-
-
-static struct rsn_pmksa_cache_entry *
-pmksa_cache_clone_entry(struct rsn_pmksa_cache *pmksa,
- const struct rsn_pmksa_cache_entry *old_entry,
- const u8 *aa)
-{
- struct rsn_pmksa_cache_entry *new_entry;
-
- new_entry = pmksa_cache_add(pmksa, old_entry->pmk, old_entry->pmk_len,
- aa, pmksa->sm->own_addr,
- old_entry->network_ctx, old_entry->akmp);
- 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
- * @pmksa: Pointer to PMKSA cache data from pmksa_cache_init()
- * @network_ctx: Network configuration context
- * @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.
- */
-struct rsn_pmksa_cache_entry *
-pmksa_cache_get_opportunistic(struct rsn_pmksa_cache *pmksa, void *network_ctx,
- const u8 *aa)
-{
- struct rsn_pmksa_cache_entry *entry = pmksa->pmksa;
-
- if (network_ctx == NULL)
- return NULL;
- while (entry) {
- if (entry->network_ctx == network_ctx) {
- entry = pmksa_cache_clone_entry(pmksa, 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_entry * 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
- * @network_ctx: Network configuration context
- * @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, void *network_ctx,
- int try_opportunistic)
-{
- struct rsn_pmksa_cache *pmksa = sm->pmksa;
- sm->cur_pmksa = NULL;
- if (pmkid)
- sm->cur_pmksa = pmksa_cache_get(pmksa, NULL, pmkid);
- if (sm->cur_pmksa == NULL && bssid)
- sm->cur_pmksa = pmksa_cache_get(pmksa, bssid, NULL);
- if (sm->cur_pmksa == NULL && try_opportunistic && bssid)
- sm->cur_pmksa = pmksa_cache_get_opportunistic(pmksa,
- network_ctx,
- 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
- * @pmksa: Pointer to PMKSA cache data from pmksa_cache_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 rsn_pmksa_cache *pmksa, char *buf, size_t len)
-{
- int i, ret;
- char *pos = buf;
- struct rsn_pmksa_cache_entry *entry;
- struct os_time now;
-
- os_get_time(&now);
- ret = os_snprintf(pos, buf + len - pos,
- "Index / AA / PMKID / expiration (in seconds) / "
- "opportunistic\n");
- if (ret < 0 || ret >= buf + len - pos)
- return pos - buf;
- pos += ret;
- i = 0;
- entry = pmksa->pmksa;
- while (entry) {
- i++;
- ret = os_snprintf(pos, buf + len - pos, "%d " MACSTR " ",
- i, MAC2STR(entry->aa));
- if (ret < 0 || ret >= buf + len - pos)
- return pos - buf;
- pos += ret;
- pos += wpa_snprintf_hex(pos, buf + len - pos, entry->pmkid,
- PMKID_LEN);
- ret = os_snprintf(pos, buf + len - pos, " %d %d\n",
- (int) (entry->expiration - now.sec),
- entry->opportunistic);
- if (ret < 0 || ret >= buf + len - pos)
- return pos - buf;
- pos += ret;
- entry = entry->next;
- }
- return pos - buf;
-}
-
-
-/**
- * pmksa_cache_init - Initialize PMKSA cache
- * @free_cb: Callback function to be called when a PMKSA cache entry is freed
- * @ctx: Context pointer for free_cb function
- * @sm: Pointer to WPA state machine data from wpa_sm_init()
- * Returns: Pointer to PMKSA cache data or %NULL on failure
- */
-struct rsn_pmksa_cache *
-pmksa_cache_init(void (*free_cb)(struct rsn_pmksa_cache_entry *entry,
- void *ctx, int replace),
- void *ctx, struct wpa_sm *sm)
-{
- struct rsn_pmksa_cache *pmksa;
-
- pmksa = os_zalloc(sizeof(*pmksa));
- if (pmksa) {
- pmksa->free_cb = free_cb;
- pmksa->ctx = ctx;
- pmksa->sm = sm;
- }
-
- return pmksa;
-}
-
-#endif /* IEEE8021X_EAPOL and !CONFIG_NO_WPA2 */
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