/* * hostapd - PMKSA cache for IEEE 802.11i RSN * Copyright (c) 2004-2008, 2012-2015, Jouni Malinen * * 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 "eapol_auth/eapol_auth_sm.h" #include "eapol_auth/eapol_auth_sm_i.h" #include "radius/radius_das.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) { os_free(entry->vlan_desc); os_free(entry->identity); os_free(entry->dpp_pkhash); wpabuf_free(entry->cui); #ifndef CONFIG_NO_RADIUS radius_free_class(&entry->radius_class); #endif /* CONFIG_NO_RADIUS */ bin_clear_free(entry, sizeof(*entry)); } void pmksa_cache_free_entry(struct rsn_pmksa_cache *pmksa, struct rsn_pmksa_cache_entry *entry) { struct rsn_pmksa_cache_entry *pos, *prev; unsigned int hash; pmksa->pmksa_count--; if (pmksa->free_cb) pmksa->free_cb(entry, pmksa->ctx); /* unlink from hash list */ hash = PMKID_HASH(entry->pmkid); pos = pmksa->pmkid[hash]; prev = NULL; while (pos) { if (pos == entry) { if (prev != NULL) prev->hnext = entry->hnext; else pmksa->pmkid[hash] = entry->hnext; break; } prev = pos; pos = pos->hnext; } /* unlink from entry list */ pos = pmksa->pmksa; prev = NULL; while (pos) { if (pos == entry) { if (prev != NULL) prev->next = entry->next; else pmksa->pmksa = entry->next; break; } prev = pos; pos = pos->next; } _pmksa_cache_free_entry(entry); } /** * pmksa_cache_auth_flush - Flush all PMKSA cache entries * @pmksa: Pointer to PMKSA cache data from pmksa_cache_auth_init() */ void pmksa_cache_auth_flush(struct rsn_pmksa_cache *pmksa) { while (pmksa->pmksa) { wpa_printf(MSG_DEBUG, "RSN: Flush PMKSA cache entry for " MACSTR, MAC2STR(pmksa->pmksa->spa)); pmksa_cache_free_entry(pmksa, pmksa->pmksa); } } static void pmksa_cache_expire(void *eloop_ctx, void *timeout_ctx) { struct rsn_pmksa_cache *pmksa = eloop_ctx; struct os_reltime now; os_get_reltime(&now); while (pmksa->pmksa && pmksa->pmksa->expiration <= now.sec) { wpa_printf(MSG_DEBUG, "RSN: expired PMKSA cache entry for " MACSTR, MAC2STR(pmksa->pmksa->spa)); pmksa_cache_free_entry(pmksa, pmksa->pmksa); } pmksa_cache_set_expiration(pmksa); } static void pmksa_cache_set_expiration(struct rsn_pmksa_cache *pmksa) { int sec; struct os_reltime now; eloop_cancel_timeout(pmksa_cache_expire, pmksa, NULL); if (pmksa->pmksa == NULL) return; os_get_reltime(&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) { struct vlan_description *vlan_desc; 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); } } if (eapol->radius_cui) entry->cui = wpabuf_dup(eapol->radius_cui); #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; vlan_desc = ((struct sta_info *) eapol->sta)->vlan_desc; if (vlan_desc && vlan_desc->notempty) { entry->vlan_desc = os_zalloc(sizeof(struct vlan_description)); if (entry->vlan_desc) *entry->vlan_desc = *vlan_desc; } else { entry->vlan_desc = NULL; } entry->acct_multi_session_id = eapol->acct_multi_session_id; } void pmksa_cache_to_eapol_data(struct hostapd_data *hapd, 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); } if (entry->cui) { wpabuf_free(eapol->radius_cui); eapol->radius_cui = wpabuf_dup(entry->cui); } #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; #ifndef CONFIG_NO_VLAN ap_sta_set_vlan(hapd, eapol->sta, entry->vlan_desc); #endif /* CONFIG_NO_VLAN */ eapol->acct_multi_session_id = entry->acct_multi_session_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; int hash; /* 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; } hash = PMKID_HASH(entry->pmkid); entry->hnext = pmksa->pmkid[hash]; pmksa->pmkid[hash] = entry; pmksa->pmksa_count++; if (prev == NULL) pmksa_cache_set_expiration(pmksa); 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) * @pmkid: Calculated PMKID * @kck: Key confirmation key or %NULL if not yet derived * @kck_len: KCK length in bytes * @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 *pmkid, const u8 *kck, size_t kck_len, const u8 *aa, const u8 *spa, int session_timeout, struct eapol_state_machine *eapol, int akmp) { struct rsn_pmksa_cache_entry *entry; entry = pmksa_cache_auth_create_entry(pmk, pmk_len, pmkid, kck, kck_len, aa, spa, session_timeout, eapol, akmp); if (pmksa_cache_auth_add_entry(pmksa, entry) < 0) return NULL; return entry; } /** * pmksa_cache_auth_create_entry - Create a PMKSA cache entry * @pmk: The new pairwise master key * @pmk_len: PMK length in bytes, usually PMK_LEN (32) * @pmkid: Calculated PMKID * @kck: Key confirmation key or %NULL if not yet derived * @kck_len: KCK length in bytes * @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 creates a PMKSA entry. */ struct rsn_pmksa_cache_entry * pmksa_cache_auth_create_entry(const u8 *pmk, size_t pmk_len, const u8 *pmkid, const u8 *kck, size_t kck_len, const u8 *aa, const u8 *spa, int session_timeout, struct eapol_state_machine *eapol, int akmp) { struct rsn_pmksa_cache_entry *entry; struct os_reltime now; if (pmk_len > PMK_LEN_MAX) return NULL; if (wpa_key_mgmt_suite_b(akmp) && !kck) return NULL; entry = os_zalloc(sizeof(*entry)); if (entry == NULL) return NULL; os_memcpy(entry->pmk, pmk, pmk_len); entry->pmk_len = pmk_len; if (pmkid) os_memcpy(entry->pmkid, pmkid, PMKID_LEN); else if (akmp == WPA_KEY_MGMT_IEEE8021X_SUITE_B_192) rsn_pmkid_suite_b_192(kck, kck_len, aa, spa, entry->pmkid); else if (wpa_key_mgmt_suite_b(akmp)) rsn_pmkid_suite_b(kck, kck_len, aa, spa, entry->pmkid); else rsn_pmkid(pmk, pmk_len, aa, spa, entry->pmkid, akmp); os_get_reltime(&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); return entry; } /** * pmksa_cache_auth_add_entry - Add a PMKSA cache entry * @pmksa: Pointer to PMKSA cache data from pmksa_cache_auth_init() * @entry: Pointer to PMKSA cache entry * * This function adds PMKSA cache entry 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. */ int pmksa_cache_auth_add_entry(struct rsn_pmksa_cache *pmksa, struct rsn_pmksa_cache_entry *entry) { struct rsn_pmksa_cache_entry *pos; if (entry == NULL) return -1; /* Replace an old entry for the same STA (if found) with the new entry */ pos = pmksa_cache_auth_get(pmksa, entry->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 0; } 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); } } if (old_entry->cui) entry->cui = wpabuf_dup(old_entry->cui); #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; if (old_entry->vlan_desc) { entry->vlan_desc = os_zalloc(sizeof(struct vlan_description)); if (entry->vlan_desc) *entry->vlan_desc = *old_entry->vlan_desc; } else { entry->vlan_desc = NULL; } 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); pmksa->pmksa_count = 0; pmksa->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) { for (entry = pmksa->pmkid[PMKID_HASH(pmkid)]; entry; entry = entry->hnext) { if ((spa == NULL || os_memcmp(entry->spa, spa, ETH_ALEN) == 0) && os_memcmp(entry->pmkid, pmkid, PMKID_LEN) == 0) return entry; } } else { for (entry = pmksa->pmksa; entry; entry = entry->next) { if (spa == NULL || os_memcmp(entry->spa, spa, ETH_ALEN) == 0) return entry; } } 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]; for (entry = pmksa->pmksa; entry; entry = entry->next) { if (os_memcmp(entry->spa, spa, ETH_ALEN) != 0) continue; if (wpa_key_mgmt_sae(entry->akmp) || wpa_key_mgmt_fils(entry->akmp)) { if (os_memcmp(entry->pmkid, pmkid, PMKID_LEN) == 0) return entry; continue; } rsn_pmkid(entry->pmk, entry->pmk_len, aa, spa, new_pmkid, entry->akmp); if (os_memcmp(new_pmkid, pmkid, PMKID_LEN) == 0) return entry; } 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; } static int das_attr_match(struct rsn_pmksa_cache_entry *entry, struct radius_das_attrs *attr) { int match = 0; if (attr->sta_addr) { if (os_memcmp(attr->sta_addr, entry->spa, ETH_ALEN) != 0) return 0; match++; } if (attr->acct_multi_session_id) { char buf[20]; if (attr->acct_multi_session_id_len != 16) return 0; os_snprintf(buf, sizeof(buf), "%016llX", (unsigned long long) entry->acct_multi_session_id); if (os_memcmp(attr->acct_multi_session_id, buf, 16) != 0) return 0; match++; } if (attr->cui) { if (!entry->cui || attr->cui_len != wpabuf_len(entry->cui) || os_memcmp(attr->cui, wpabuf_head(entry->cui), attr->cui_len) != 0) return 0; match++; } if (attr->user_name) { if (!entry->identity || attr->user_name_len != entry->identity_len || os_memcmp(attr->user_name, entry->identity, attr->user_name_len) != 0) return 0; match++; } return match; } int pmksa_cache_auth_radius_das_disconnect(struct rsn_pmksa_cache *pmksa, struct radius_das_attrs *attr) { int found = 0; struct rsn_pmksa_cache_entry *entry, *prev; if (attr->acct_session_id) return -1; entry = pmksa->pmksa; while (entry) { if (das_attr_match(entry, attr)) { found++; prev = entry; entry = entry->next; pmksa_cache_free_entry(pmksa, prev); continue; } entry = entry->next; } return found ? 0 : -1; } /** * pmksa_cache_auth_list - Dump text list of entries in PMKSA cache * @pmksa: Pointer to PMKSA cache data from pmksa_cache_auth_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_auth_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_reltime now; os_get_reltime(&now); ret = os_snprintf(pos, buf + len - pos, "Index / SPA / PMKID / expiration (in seconds) / opportunistic\n"); if (os_snprintf_error(buf + len - pos, ret)) return pos - buf; pos += ret; i = 0; entry = pmksa->pmksa; while (entry) { ret = os_snprintf(pos, buf + len - pos, "%d " MACSTR " ", i, MAC2STR(entry->spa)); if (os_snprintf_error(buf + len - pos, ret)) 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 (os_snprintf_error(buf + len - pos, ret)) return pos - buf; pos += ret; entry = entry->next; } return pos - buf; } #ifdef CONFIG_PMKSA_CACHE_EXTERNAL #ifdef CONFIG_MESH /** * pmksa_cache_auth_list_mesh - Dump text list of entries in PMKSA cache * @pmksa: Pointer to PMKSA cache data from pmksa_cache_auth_init() * @addr: MAC address of the peer (NULL means any) * @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_GET command to store * in external storage. */ int pmksa_cache_auth_list_mesh(struct rsn_pmksa_cache *pmksa, const u8 *addr, char *buf, size_t len) { int ret; char *pos, *end; struct rsn_pmksa_cache_entry *entry; struct os_reltime now; pos = buf; end = buf + len; os_get_reltime(&now); /* * Entry format: * */ for (entry = pmksa->pmksa; entry; entry = entry->next) { if (addr && os_memcmp(entry->spa, addr, ETH_ALEN) != 0) continue; ret = os_snprintf(pos, end - pos, MACSTR " ", MAC2STR(entry->spa)); if (os_snprintf_error(end - pos, ret)) return 0; pos += ret; pos += wpa_snprintf_hex(pos, end - pos, entry->pmkid, PMKID_LEN); ret = os_snprintf(pos, end - pos, " "); if (os_snprintf_error(end - pos, ret)) return 0; pos += ret; pos += wpa_snprintf_hex(pos, end - pos, entry->pmk, entry->pmk_len); ret = os_snprintf(pos, end - pos, " %d\n", (int) (entry->expiration - now.sec)); if (os_snprintf_error(end - pos, ret)) return 0; pos += ret; } return pos - buf; } #endif /* CONFIG_MESH */ #endif /* CONFIG_PMKSA_CACHE_EXTERNAL */