--- /dev/null
+/*
+ * hostapd - PMKSA cache for IEEE 802.11i RSN
+ * 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 "utils/includes.h"
+
+#include "utils/common.h"
+#include "utils/eloop.h"
+#include "eapol_auth/eapol_auth_sm.h"
+#include "eapol_auth/eapol_auth_sm_i.h"
+#include "sta_info.h"
+#include "ap_config.h"
+#include "pmksa_cache_auth.h"
+
+
+static const int pmksa_cache_max_entries = 1024;
+static const int dot11RSNAConfigPMKLifetime = 43200;
+
+struct rsn_pmksa_cache {
+#define PMKID_HASH_SIZE 128
+#define PMKID_HASH(pmkid) (unsigned int) ((pmkid)[0] & 0x7f)
+ struct rsn_pmksa_cache_entry *pmkid[PMKID_HASH_SIZE];
+ struct rsn_pmksa_cache_entry *pmksa;
+ int pmksa_count;
+
+ void (*free_cb)(struct rsn_pmksa_cache_entry *entry, void *ctx);
+ 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)
+{
+ if (entry == NULL)
+ return;
+ os_free(entry->identity);
+#ifndef CONFIG_NO_RADIUS
+ radius_free_class(&entry->radius_class);
+#endif /* CONFIG_NO_RADIUS */
+ os_free(entry);
+}
+
+
+static void pmksa_cache_free_entry(struct rsn_pmksa_cache *pmksa,
+ struct rsn_pmksa_cache_entry *entry)
+{
+ struct rsn_pmksa_cache_entry *pos, *prev;
+
+ pmksa->pmksa_count--;
+ pmksa->free_cb(entry, pmksa->ctx);
+ pos = pmksa->pmkid[PMKID_HASH(entry->pmkid)];
+ prev = NULL;
+ while (pos) {
+ if (pos == entry) {
+ if (prev != NULL) {
+ prev->hnext = pos->hnext;
+ } else {
+ pmksa->pmkid[PMKID_HASH(entry->pmkid)] =
+ pos->hnext;
+ }
+ break;
+ }
+ prev = pos;
+ pos = pos->hnext;
+ }
+
+ pos = pmksa->pmksa;
+ prev = NULL;
+ while (pos) {
+ if (pos == entry) {
+ if (prev != NULL)
+ prev->next = pos->next;
+ else
+ pmksa->pmksa = pos->next;
+ break;
+ }
+ prev = pos;
+ pos = pos->next;
+ }
+ _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->spa));
+ pmksa_cache_free_entry(pmksa, entry);
+ }
+
+ pmksa_cache_set_expiration(pmksa);
+}
+
+
+static void pmksa_cache_set_expiration(struct rsn_pmksa_cache *pmksa)
+{
+ int sec;
+ struct os_time now;
+
+ eloop_cancel_timeout(pmksa_cache_expire, 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);
+}
+
+
+static void pmksa_cache_from_eapol_data(struct rsn_pmksa_cache_entry *entry,
+ struct eapol_state_machine *eapol)
+{
+ if (eapol == NULL)
+ return;
+
+ if (eapol->identity) {
+ entry->identity = os_malloc(eapol->identity_len);
+ if (entry->identity) {
+ entry->identity_len = eapol->identity_len;
+ os_memcpy(entry->identity, eapol->identity,
+ eapol->identity_len);
+ }
+ }
+
+#ifndef CONFIG_NO_RADIUS
+ radius_copy_class(&entry->radius_class, &eapol->radius_class);
+#endif /* CONFIG_NO_RADIUS */
+
+ entry->eap_type_authsrv = eapol->eap_type_authsrv;
+ entry->vlan_id = ((struct sta_info *) eapol->sta)->vlan_id;
+}
+
+
+void pmksa_cache_to_eapol_data(struct rsn_pmksa_cache_entry *entry,
+ struct eapol_state_machine *eapol)
+{
+ if (entry == NULL || eapol == NULL)
+ return;
+
+ if (entry->identity) {
+ os_free(eapol->identity);
+ eapol->identity = os_malloc(entry->identity_len);
+ if (eapol->identity) {
+ eapol->identity_len = entry->identity_len;
+ os_memcpy(eapol->identity, entry->identity,
+ entry->identity_len);
+ }
+ wpa_hexdump_ascii(MSG_DEBUG, "STA identity from PMKSA",
+ eapol->identity, eapol->identity_len);
+ }
+
+#ifndef CONFIG_NO_RADIUS
+ radius_free_class(&eapol->radius_class);
+ radius_copy_class(&eapol->radius_class, &entry->radius_class);
+#endif /* CONFIG_NO_RADIUS */
+ if (eapol->radius_class.attr) {
+ wpa_printf(MSG_DEBUG, "Copied %lu Class attribute(s) from "
+ "PMKSA", (unsigned long) eapol->radius_class.count);
+ }
+
+ eapol->eap_type_authsrv = entry->eap_type_authsrv;
+ ((struct sta_info *) eapol->sta)->vlan_id = entry->vlan_id;
+}
+
+
+static void pmksa_cache_link_entry(struct rsn_pmksa_cache *pmksa,
+ struct rsn_pmksa_cache_entry *entry)
+{
+ struct rsn_pmksa_cache_entry *pos, *prev;
+
+ /* 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;
+ } else {
+ entry->next = prev->next;
+ prev->next = entry;
+ }
+ entry->hnext = pmksa->pmkid[PMKID_HASH(entry->pmkid)];
+ pmksa->pmkid[PMKID_HASH(entry->pmkid)] = entry;
+
+ pmksa->pmksa_count++;
+ wpa_printf(MSG_DEBUG, "RSN: added PMKSA cache entry for " MACSTR,
+ MAC2STR(entry->spa));
+ wpa_hexdump(MSG_DEBUG, "RSN: added PMKID", entry->pmkid, PMKID_LEN);
+}
+
+
+/**
+ * pmksa_cache_auth_add - Add a PMKSA cache entry
+ * @pmksa: Pointer to PMKSA cache data from pmksa_cache_auth_init()
+ * @pmk: The new pairwise master key
+ * @pmk_len: PMK length in bytes, usually PMK_LEN (32)
+ * @aa: Authenticator address
+ * @spa: Supplicant address
+ * @session_timeout: Session timeout
+ * @eapol: Pointer to EAPOL state machine data
+ * @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 Supplicant,
+ * this entry will be replaced with the new entry. PMKID will be calculated
+ * based on the PMK.
+ */
+struct rsn_pmksa_cache_entry *
+pmksa_cache_auth_add(struct rsn_pmksa_cache *pmksa,
+ const u8 *pmk, size_t pmk_len,
+ const u8 *aa, const u8 *spa, int session_timeout,
+ struct eapol_state_machine *eapol, int akmp)
+{
+ struct rsn_pmksa_cache_entry *entry, *pos;
+ 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;
+ if (session_timeout > 0)
+ entry->expiration += session_timeout;
+ else
+ entry->expiration += dot11RSNAConfigPMKLifetime;
+ entry->akmp = akmp;
+ os_memcpy(entry->spa, spa, ETH_ALEN);
+ pmksa_cache_from_eapol_data(entry, eapol);
+
+ /* Replace an old entry for the same STA (if found) with the new entry
+ */
+ pos = pmksa_cache_auth_get(pmksa, spa, NULL);
+ if (pos)
+ pmksa_cache_free_entry(pmksa, pos);
+
+ if (pmksa->pmksa_count >= pmksa_cache_max_entries && pmksa->pmksa) {
+ /* Remove the oldest entry to make room for the new entry */
+ wpa_printf(MSG_DEBUG, "RSN: removed the oldest PMKSA cache "
+ "entry (for " MACSTR ") to make room for new one",
+ MAC2STR(pmksa->pmksa->spa));
+ pmksa_cache_free_entry(pmksa, pmksa->pmksa);
+ }
+
+ pmksa_cache_link_entry(pmksa, entry);
+
+ return entry;
+}
+
+
+struct rsn_pmksa_cache_entry *
+pmksa_cache_add_okc(struct rsn_pmksa_cache *pmksa,
+ const struct rsn_pmksa_cache_entry *old_entry,
+ const u8 *aa, const u8 *pmkid)
+{
+ struct rsn_pmksa_cache_entry *entry;
+
+ entry = os_zalloc(sizeof(*entry));
+ if (entry == NULL)
+ return NULL;
+ os_memcpy(entry->pmkid, pmkid, PMKID_LEN);
+ os_memcpy(entry->pmk, old_entry->pmk, old_entry->pmk_len);
+ entry->pmk_len = old_entry->pmk_len;
+ entry->expiration = old_entry->expiration;
+ entry->akmp = old_entry->akmp;
+ os_memcpy(entry->spa, old_entry->spa, ETH_ALEN);
+ entry->opportunistic = 1;
+ if (old_entry->identity) {
+ entry->identity = os_malloc(old_entry->identity_len);
+ if (entry->identity) {
+ entry->identity_len = old_entry->identity_len;
+ os_memcpy(entry->identity, old_entry->identity,
+ old_entry->identity_len);
+ }
+ }
+#ifndef CONFIG_NO_RADIUS
+ radius_copy_class(&entry->radius_class, &old_entry->radius_class);
+#endif /* CONFIG_NO_RADIUS */
+ entry->eap_type_authsrv = old_entry->eap_type_authsrv;
+ entry->vlan_id = old_entry->vlan_id;
+ entry->opportunistic = 1;
+
+ pmksa_cache_link_entry(pmksa, entry);
+
+ return entry;
+}
+
+
+/**
+ * pmksa_cache_auth_deinit - Free all entries in PMKSA cache
+ * @pmksa: Pointer to PMKSA cache data from pmksa_cache_auth_init()
+ */
+void pmksa_cache_auth_deinit(struct rsn_pmksa_cache *pmksa)
+{
+ struct rsn_pmksa_cache_entry *entry, *prev;
+ int i;
+
+ if (pmksa == NULL)
+ return;
+
+ entry = pmksa->pmksa;
+ while (entry) {
+ prev = entry;
+ entry = entry->next;
+ _pmksa_cache_free_entry(prev);
+ }
+ eloop_cancel_timeout(pmksa_cache_expire, pmksa, NULL);
+ for (i = 0; i < PMKID_HASH_SIZE; i++)
+ pmksa->pmkid[i] = NULL;
+ os_free(pmksa);
+}
+
+
+/**
+ * pmksa_cache_auth_get - Fetch a PMKSA cache entry
+ * @pmksa: Pointer to PMKSA cache data from pmksa_cache_auth_init()
+ * @spa: Supplicant 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_auth_get(struct rsn_pmksa_cache *pmksa,
+ const u8 *spa, const u8 *pmkid)
+{
+ struct rsn_pmksa_cache_entry *entry;
+
+ if (pmkid)
+ entry = pmksa->pmkid[PMKID_HASH(pmkid)];
+ else
+ entry = pmksa->pmksa;
+ while (entry) {
+ if ((spa == NULL ||
+ os_memcmp(entry->spa, spa, ETH_ALEN) == 0) &&
+ (pmkid == NULL ||
+ os_memcmp(entry->pmkid, pmkid, PMKID_LEN) == 0))
+ return entry;
+ entry = pmkid ? entry->hnext : entry->next;
+ }
+ return NULL;
+}
+
+
+/**
+ * pmksa_cache_get_okc - Fetch a PMKSA cache entry using OKC
+ * @pmksa: Pointer to PMKSA cache data from pmksa_cache_auth_init()
+ * @aa: Authenticator address
+ * @spa: Supplicant address
+ * @pmkid: PMKID
+ * Returns: Pointer to PMKSA cache entry or %NULL if no match was found
+ *
+ * Use opportunistic key caching (OKC) to find a PMK for a supplicant.
+ */
+struct rsn_pmksa_cache_entry * pmksa_cache_get_okc(
+ struct rsn_pmksa_cache *pmksa, const u8 *aa, const u8 *spa,
+ const u8 *pmkid)
+{
+ struct rsn_pmksa_cache_entry *entry;
+ u8 new_pmkid[PMKID_LEN];
+
+ entry = pmksa->pmksa;
+ while (entry) {
+ if (os_memcmp(entry->spa, spa, ETH_ALEN) != 0)
+ continue;
+ rsn_pmkid(entry->pmk, entry->pmk_len, aa, spa, new_pmkid,
+ wpa_key_mgmt_sha256(entry->akmp));
+ if (os_memcmp(new_pmkid, pmkid, PMKID_LEN) == 0)
+ return entry;
+ entry = entry->next;
+ }
+ return NULL;
+}
+
+
+/**
+ * pmksa_cache_auth_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
+ * Returns: Pointer to PMKSA cache data or %NULL on failure
+ */
+struct rsn_pmksa_cache *
+pmksa_cache_auth_init(void (*free_cb)(struct rsn_pmksa_cache_entry *entry,
+ void *ctx), void *ctx)
+{
+ struct rsn_pmksa_cache *pmksa;
+
+ pmksa = os_zalloc(sizeof(*pmksa));
+ if (pmksa) {
+ pmksa->free_cb = free_cb;
+ pmksa->ctx = ctx;
+ }
+
+ return pmksa;
+}
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