/*
* hostapd / IEEE 802.11 authentication (ACL)
* Copyright (c) 2003-2012, Jouni Malinen <j@w1.fi>
*
* This software may be distributed under the terms of the BSD license.
* See README for more details.
*
* Access control list for IEEE 802.11 authentication can uses statically
* configured ACL from configuration files or an external RADIUS server.
* Results from external RADIUS queries are cached to allow faster
* authentication frame processing.
*/
#include "utils/includes.h"
#include "utils/common.h"
#include "utils/eloop.h"
#include "radius/radius.h"
#include "radius/radius_client.h"
#include "hostapd.h"
#include "ap_config.h"
#include "ap_drv_ops.h"
#include "ieee802_11.h"
#include "ieee802_1x.h"
#include "ieee802_11_auth.h"
#define RADIUS_ACL_TIMEOUT 30
struct hostapd_cached_radius_acl {
struct os_reltime timestamp;
macaddr addr;
int accepted; /* HOSTAPD_ACL_* */
struct hostapd_cached_radius_acl *next;
u32 session_timeout;
u32 acct_interim_interval;
struct vlan_description vlan_id;
struct hostapd_sta_wpa_psk_short *psk;
char *identity;
char *radius_cui;
};
struct hostapd_acl_query_data {
struct os_reltime timestamp;
u8 radius_id;
macaddr addr;
u8 *auth_msg; /* IEEE 802.11 authentication frame from station */
size_t auth_msg_len;
struct hostapd_acl_query_data *next;
};
#ifndef CONFIG_NO_RADIUS
static void hostapd_acl_cache_free_entry(struct hostapd_cached_radius_acl *e)
{
os_free(e->identity);
os_free(e->radius_cui);
hostapd_free_psk_list(e->psk);
os_free(e);
}
static void hostapd_acl_cache_free(struct hostapd_cached_radius_acl *acl_cache)
{
struct hostapd_cached_radius_acl *prev;
while (acl_cache) {
prev = acl_cache;
acl_cache = acl_cache->next;
hostapd_acl_cache_free_entry(prev);
}
}
static void copy_psk_list(struct hostapd_sta_wpa_psk_short **psk,
struct hostapd_sta_wpa_psk_short *src)
{
if (!psk)
return;
if (src)
src->ref++;
*psk = src;
}
static int hostapd_acl_cache_get(struct hostapd_data *hapd, const u8 *addr,
u32 *session_timeout,
u32 *acct_interim_interval,
struct vlan_description *vlan_id,
struct hostapd_sta_wpa_psk_short **psk,
char **identity, char **radius_cui)
{
struct hostapd_cached_radius_acl *entry;
struct os_reltime now;
os_get_reltime(&now);
for (entry = hapd->acl_cache; entry; entry = entry->next) {
if (os_memcmp(entry->addr, addr, ETH_ALEN) != 0)
continue;
if (os_reltime_expired(&now, &entry->timestamp,
RADIUS_ACL_TIMEOUT))
return -1; /* entry has expired */
if (entry->accepted == HOSTAPD_ACL_ACCEPT_TIMEOUT)
if (session_timeout)
*session_timeout = entry->session_timeout;
if (acct_interim_interval)
*acct_interim_interval =
entry->acct_interim_interval;
if (vlan_id)
*vlan_id = entry->vlan_id;
copy_psk_list(psk, entry->psk);
if (identity) {
if (entry->identity)
*identity = os_strdup(entry->identity);
else
*identity = NULL;
}
if (radius_cui) {
if (entry->radius_cui)
*radius_cui = os_strdup(entry->radius_cui);
else
*radius_cui = NULL;
}
return entry->accepted;
}
return -1;
}
#endif /* CONFIG_NO_RADIUS */
static void hostapd_acl_query_free(struct hostapd_acl_query_data *query)
{
if (query == NULL)
return;
os_free(query->auth_msg);
os_free(query);
}
#ifndef CONFIG_NO_RADIUS
static int hostapd_radius_acl_query(struct hostapd_data *hapd, const u8 *addr,
struct hostapd_acl_query_data *query)
{
struct radius_msg *msg;
char buf[128];
query->radius_id = radius_client_get_id(hapd->radius);
msg = radius_msg_new(RADIUS_CODE_ACCESS_REQUEST, query->radius_id);
if (msg == NULL)
return -1;
if (radius_msg_make_authenticator(msg) < 0) {
wpa_printf(MSG_INFO, "Could not make Request Authenticator");
goto fail;
}
os_snprintf(buf, sizeof(buf), RADIUS_ADDR_FORMAT, MAC2STR(addr));
if (!radius_msg_add_attr(msg, RADIUS_ATTR_USER_NAME, (u8 *) buf,
os_strlen(buf))) {
wpa_printf(MSG_DEBUG, "Could not add User-Name");
goto fail;
}
if (!radius_msg_add_attr_user_password(
msg, (u8 *) buf, os_strlen(buf),
hapd->conf->radius->auth_server->shared_secret,
hapd->conf->radius->auth_server->shared_secret_len)) {
wpa_printf(MSG_DEBUG, "Could not add User-Password");
goto fail;
}
if (add_common_radius_attr(hapd, hapd->conf->radius_auth_req_attr,
NULL, msg) < 0)
goto fail;
os_snprintf(buf, sizeof(buf), RADIUS_802_1X_ADDR_FORMAT,
MAC2STR(addr));
if (!radius_msg_add_attr(msg, RADIUS_ATTR_CALLING_STATION_ID,
(u8 *) buf, os_strlen(buf))) {
wpa_printf(MSG_DEBUG, "Could not add Calling-Station-Id");
goto fail;
}
os_snprintf(buf, sizeof(buf), "CONNECT 11Mbps 802.11b");
if (!radius_msg_add_attr(msg, RADIUS_ATTR_CONNECT_INFO,
(u8 *) buf, os_strlen(buf))) {
wpa_printf(MSG_DEBUG, "Could not add Connect-Info");
goto fail;
}
if (radius_client_send(hapd->radius, msg, RADIUS_AUTH, addr) < 0)
goto fail;
return 0;
fail:
radius_msg_free(msg);
return -1;
}
#endif /* CONFIG_NO_RADIUS */
/**
* hostapd_check_acl - Check a specified STA against accept/deny ACLs
* @hapd: hostapd BSS data
* @addr: MAC address of the STA
* @vlan_id: Buffer for returning VLAN ID
* Returns: HOSTAPD_ACL_ACCEPT, HOSTAPD_ACL_REJECT, or HOSTAPD_ACL_PENDING
*/
int hostapd_check_acl(struct hostapd_data *hapd, const u8 *addr,
struct vlan_description *vlan_id)
{
if (hostapd_maclist_found(hapd->conf->accept_mac,
hapd->conf->num_accept_mac, addr, vlan_id))
return HOSTAPD_ACL_ACCEPT;
if (hostapd_maclist_found(hapd->conf->deny_mac,
hapd->conf->num_deny_mac, addr, vlan_id))
return HOSTAPD_ACL_REJECT;
if (hapd->conf->macaddr_acl == ACCEPT_UNLESS_DENIED)
return HOSTAPD_ACL_ACCEPT;
if (hapd->conf->macaddr_acl == DENY_UNLESS_ACCEPTED)
return HOSTAPD_ACL_REJECT;
return HOSTAPD_ACL_PENDING;
}
/**
* hostapd_allowed_address - Check whether a specified STA can be authenticated
* @hapd: hostapd BSS data
* @addr: MAC address of the STA
* @msg: Authentication message
* @len: Length of msg in octets
* @session_timeout: Buffer for returning session timeout (from RADIUS)
* @acct_interim_interval: Buffer for returning account interval (from RADIUS)
* @vlan_id: Buffer for returning VLAN ID
* @psk: Linked list buffer for returning WPA PSK
* @identity: Buffer for returning identity (from RADIUS)
* @radius_cui: Buffer for returning CUI (from RADIUS)
* @is_probe_req: Whether this query for a Probe Request frame
* Returns: HOSTAPD_ACL_ACCEPT, HOSTAPD_ACL_REJECT, or HOSTAPD_ACL_PENDING
*
* The caller is responsible for freeing the returned *identity and *radius_cui
* values with os_free().
*/
int hostapd_allowed_address(struct hostapd_data *hapd, const u8 *addr,
const u8 *msg, size_t len, u32 *session_timeout,
u32 *acct_interim_interval,
struct vlan_description *vlan_id,
struct hostapd_sta_wpa_psk_short **psk,
char **identity, char **radius_cui,
int is_probe_req)
{
int res;
if (session_timeout)
*session_timeout = 0;
if (acct_interim_interval)
*acct_interim_interval = 0;
if (vlan_id)
os_memset(vlan_id, 0, sizeof(*vlan_id));
if (psk)
*psk = NULL;
if (identity)
*identity = NULL;
if (radius_cui)
*radius_cui = NULL;
res = hostapd_check_acl(hapd, addr, vlan_id);
if (res != HOSTAPD_ACL_PENDING)
return res;
if (hapd->conf->macaddr_acl == USE_EXTERNAL_RADIUS_AUTH) {
#ifdef CONFIG_NO_RADIUS
return HOSTAPD_ACL_REJECT;
#else /* CONFIG_NO_RADIUS */
struct hostapd_acl_query_data *query;
if (is_probe_req) {
/* Skip RADIUS queries for Probe Request frames to avoid
* excessive load on the authentication server. */
return HOSTAPD_ACL_ACCEPT;
};
if (hapd->conf->ssid.dynamic_vlan == DYNAMIC_VLAN_DISABLED)
vlan_id = NULL;
/* Check whether ACL cache has an entry for this station */
res = hostapd_acl_cache_get(hapd, addr, session_timeout,
acct_interim_interval, vlan_id, psk,
identity, radius_cui);
if (res == HOSTAPD_ACL_ACCEPT ||
res == HOSTAPD_ACL_ACCEPT_TIMEOUT)
return res;
if (res == HOSTAPD_ACL_REJECT)
return HOSTAPD_ACL_REJECT;
query = hapd->acl_queries;
while (query) {
if (os_memcmp(query->addr, addr, ETH_ALEN) == 0) {
/* pending query in RADIUS retransmit queue;
* do not generate a new one */
if (identity) {
os_free(*identity);
*identity = NULL;
}
if (radius_cui) {
os_free(*radius_cui);
*radius_cui = NULL;
}
return HOSTAPD_ACL_PENDING;
}
query = query->next;
}
if (!hapd->conf->radius->auth_server)
return HOSTAPD_ACL_REJECT;
/* No entry in the cache - query external RADIUS server */
query = os_zalloc(sizeof(*query));
if (query == NULL) {
wpa_printf(MSG_ERROR, "malloc for query data failed");
return HOSTAPD_ACL_REJECT;
}
os_get_reltime(&query->timestamp);
os_memcpy(query->addr, addr, ETH_ALEN);
if (hostapd_radius_acl_query(hapd, addr, query)) {
wpa_printf(MSG_DEBUG, "Failed to send Access-Request "
"for ACL query.");
hostapd_acl_query_free(query);
return HOSTAPD_ACL_REJECT;
}
query->auth_msg = os_memdup(msg, len);
if (query->auth_msg == NULL) {
wpa_printf(MSG_ERROR, "Failed to allocate memory for "
"auth frame.");
hostapd_acl_query_free(query);
return HOSTAPD_ACL_REJECT;
}
query->auth_msg_len = len;
query->next = hapd->acl_queries;
hapd->acl_queries = query;
/* Queued data will be processed in hostapd_acl_recv_radius()
* when RADIUS server replies to the sent Access-Request. */
return HOSTAPD_ACL_PENDING;
#endif /* CONFIG_NO_RADIUS */
}
return HOSTAPD_ACL_REJECT;
}
#ifndef CONFIG_NO_RADIUS
static void hostapd_acl_expire_cache(struct hostapd_data *hapd,
struct os_reltime *now)
{
struct hostapd_cached_radius_acl *prev, *entry, *tmp;
prev = NULL;
entry = hapd->acl_cache;
while (entry) {
if (os_reltime_expired(now, &entry->timestamp,
RADIUS_ACL_TIMEOUT)) {
wpa_printf(MSG_DEBUG, "Cached ACL entry for " MACSTR
" has expired.", MAC2STR(entry->addr));
if (prev)
prev->next = entry->next;
else
hapd->acl_cache = entry->next;
hostapd_drv_set_radius_acl_expire(hapd, entry->addr);
tmp = entry;
entry = entry->next;
hostapd_acl_cache_free_entry(tmp);
continue;
}
prev = entry;
entry = entry->next;
}
}
static void hostapd_acl_expire_queries(struct hostapd_data *hapd,
struct os_reltime *now)
{
struct hostapd_acl_query_data *prev, *entry, *tmp;
prev = NULL;
entry = hapd->acl_queries;
while (entry) {
if (os_reltime_expired(now, &entry->timestamp,
RADIUS_ACL_TIMEOUT)) {
wpa_printf(MSG_DEBUG, "ACL query for " MACSTR
" has expired.", MAC2STR(entry->addr));
if (prev)
prev->next = entry->next;
else
hapd->acl_queries = entry->next;
tmp = entry;
entry = entry->next;
hostapd_acl_query_free(tmp);
continue;
}
prev = entry;
entry = entry->next;
}
}
/**
* hostapd_acl_expire - ACL cache expiration callback
* @hapd: struct hostapd_data *
*/
void hostapd_acl_expire(struct hostapd_data *hapd)
{
struct os_reltime now;
os_get_reltime(&now);
hostapd_acl_expire_cache(hapd, &now);
hostapd_acl_expire_queries(hapd, &now);
}
static void decode_tunnel_passwords(struct hostapd_data *hapd,
const u8 *shared_secret,
size_t shared_secret_len,
struct radius_msg *msg,
struct radius_msg *req,
struct hostapd_cached_radius_acl *cache)
{
int passphraselen;
char *passphrase;
size_t i;
struct hostapd_sta_wpa_psk_short *psk;
/*
* Decode all tunnel passwords as PSK and save them into a linked list.
*/
for (i = 0; ; i++) {
passphrase = radius_msg_get_tunnel_password(
msg, &passphraselen, shared_secret, shared_secret_len,
req, i);
/*
* Passphrase is NULL iff there is no i-th Tunnel-Password
* attribute in msg.
*/
if (passphrase == NULL)
break;
/*
* Passphase should be 8..63 chars (to be hashed with SSID)
* or 64 chars hex string (no separate hashing with SSID).
*/
if (passphraselen < MIN_PASSPHRASE_LEN ||
passphraselen > MAX_PASSPHRASE_LEN + 1)
goto free_pass;
/*
* passphrase does not contain the NULL termination.
* Add it here as pbkdf2_sha1() requires it.
*/
psk = os_zalloc(sizeof(struct hostapd_sta_wpa_psk_short));
if (psk) {
if ((passphraselen == MAX_PASSPHRASE_LEN + 1) &&
(hexstr2bin(passphrase, psk->psk, PMK_LEN) < 0)) {
hostapd_logger(hapd, cache->addr,
HOSTAPD_MODULE_RADIUS,
HOSTAPD_LEVEL_WARNING,
"invalid hex string (%d chars) in Tunnel-Password",
passphraselen);
goto skip;
} else if (passphraselen <= MAX_PASSPHRASE_LEN) {
os_memcpy(psk->passphrase, passphrase,
passphraselen);
psk->is_passphrase = 1;
}
psk->next = cache->psk;
cache->psk = psk;
psk = NULL;
}
skip:
os_free(psk);
free_pass:
os_free(passphrase);
}
}
/**
* hostapd_acl_recv_radius - Process incoming RADIUS Authentication messages
* @msg: RADIUS response message
* @req: RADIUS request message
* @shared_secret: RADIUS shared secret
* @shared_secret_len: Length of shared_secret in octets
* @data: Context data (struct hostapd_data *)
* Returns: RADIUS_RX_PROCESSED if RADIUS message was a reply to ACL query (and
* was processed here) or RADIUS_RX_UNKNOWN if not.
*/
static RadiusRxResult
hostapd_acl_recv_radius(struct radius_msg *msg, struct radius_msg *req,
const u8 *shared_secret, size_t shared_secret_len,
void *data)
{
struct hostapd_data *hapd = data;
struct hostapd_acl_query_data *query, *prev;
struct hostapd_cached_radius_acl *cache;
struct radius_hdr *hdr = radius_msg_get_hdr(msg);
query = hapd->acl_queries;
prev = NULL;
while (query) {
if (query->radius_id == hdr->identifier)
break;
prev = query;
query = query->next;
}
if (query == NULL)
return RADIUS_RX_UNKNOWN;
wpa_printf(MSG_DEBUG, "Found matching Access-Request for RADIUS "
"message (id=%d)", query->radius_id);
if (radius_msg_verify(msg, shared_secret, shared_secret_len, req, 0)) {
wpa_printf(MSG_INFO, "Incoming RADIUS packet did not have "
"correct authenticator - dropped\n");
return RADIUS_RX_INVALID_AUTHENTICATOR;
}
if (hdr->code != RADIUS_CODE_ACCESS_ACCEPT &&
hdr->code != RADIUS_CODE_ACCESS_REJECT) {
wpa_printf(MSG_DEBUG, "Unknown RADIUS message code %d to ACL "
"query", hdr->code);
return RADIUS_RX_UNKNOWN;
}
/* Insert Accept/Reject info into ACL cache */
cache = os_zalloc(sizeof(*cache));
if (cache == NULL) {
wpa_printf(MSG_DEBUG, "Failed to add ACL cache entry");
goto done;
}
os_get_reltime(&cache->timestamp);
os_memcpy(cache->addr, query->addr, sizeof(cache->addr));
if (hdr->code == RADIUS_CODE_ACCESS_ACCEPT) {
u8 *buf;
size_t len;
if (radius_msg_get_attr_int32(msg, RADIUS_ATTR_SESSION_TIMEOUT,
&cache->session_timeout) == 0)
cache->accepted = HOSTAPD_ACL_ACCEPT_TIMEOUT;
else
cache->accepted = HOSTAPD_ACL_ACCEPT;
if (radius_msg_get_attr_int32(
msg, RADIUS_ATTR_ACCT_INTERIM_INTERVAL,
&cache->acct_interim_interval) == 0 &&
cache->acct_interim_interval < 60) {
wpa_printf(MSG_DEBUG, "Ignored too small "
"Acct-Interim-Interval %d for STA " MACSTR,
cache->acct_interim_interval,
MAC2STR(query->addr));
cache->acct_interim_interval = 0;
}
if (hapd->conf->ssid.dynamic_vlan != DYNAMIC_VLAN_DISABLED)
cache->vlan_id.notempty = !!radius_msg_get_vlanid(
msg, &cache->vlan_id.untagged,
MAX_NUM_TAGGED_VLAN, cache->vlan_id.tagged);
decode_tunnel_passwords(hapd, shared_secret, shared_secret_len,
msg, req, cache);
if (radius_msg_get_attr_ptr(msg, RADIUS_ATTR_USER_NAME,
&buf, &len, NULL) == 0) {
cache->identity = os_zalloc(len + 1);
if (cache->identity)
os_memcpy(cache->identity, buf, len);
}
if (radius_msg_get_attr_ptr(
msg, RADIUS_ATTR_CHARGEABLE_USER_IDENTITY,
&buf, &len, NULL) == 0) {
cache->radius_cui = os_zalloc(len + 1);
if (cache->radius_cui)
os_memcpy(cache->radius_cui, buf, len);
}
if (hapd->conf->wpa_psk_radius == PSK_RADIUS_REQUIRED &&
!cache->psk)
cache->accepted = HOSTAPD_ACL_REJECT;
if (cache->vlan_id.notempty &&
!hostapd_vlan_valid(hapd->conf->vlan, &cache->vlan_id)) {
hostapd_logger(hapd, query->addr,
HOSTAPD_MODULE_RADIUS,
HOSTAPD_LEVEL_INFO,
"Invalid VLAN %d%s received from RADIUS server",
cache->vlan_id.untagged,
cache->vlan_id.tagged[0] ? "+" : "");
os_memset(&cache->vlan_id, 0, sizeof(cache->vlan_id));
}
if (hapd->conf->ssid.dynamic_vlan == DYNAMIC_VLAN_REQUIRED &&
!cache->vlan_id.notempty)
cache->accepted = HOSTAPD_ACL_REJECT;
} else
cache->accepted = HOSTAPD_ACL_REJECT;
cache->next = hapd->acl_cache;
hapd->acl_cache = cache;
#ifdef CONFIG_DRIVER_RADIUS_ACL
hostapd_drv_set_radius_acl_auth(hapd, query->addr, cache->accepted,
cache->session_timeout);
#else /* CONFIG_DRIVER_RADIUS_ACL */
#ifdef NEED_AP_MLME
/* Re-send original authentication frame for 802.11 processing */
wpa_printf(MSG_DEBUG, "Re-sending authentication frame after "
"successful RADIUS ACL query");
ieee802_11_mgmt(hapd, query->auth_msg, query->auth_msg_len, NULL);
#endif /* NEED_AP_MLME */
#endif /* CONFIG_DRIVER_RADIUS_ACL */
done:
if (prev == NULL)
hapd->acl_queries = query->next;
else
prev->next = query->next;
hostapd_acl_query_free(query);
return RADIUS_RX_PROCESSED;
}
#endif /* CONFIG_NO_RADIUS */
/**
* hostapd_acl_init: Initialize IEEE 802.11 ACL
* @hapd: hostapd BSS data
* Returns: 0 on success, -1 on failure
*/
int hostapd_acl_init(struct hostapd_data *hapd)
{
#ifndef CONFIG_NO_RADIUS
if (radius_client_register(hapd->radius, RADIUS_AUTH,
hostapd_acl_recv_radius, hapd))
return -1;
#endif /* CONFIG_NO_RADIUS */
return 0;
}
/**
* hostapd_acl_deinit - Deinitialize IEEE 802.11 ACL
* @hapd: hostapd BSS data
*/
void hostapd_acl_deinit(struct hostapd_data *hapd)
{
struct hostapd_acl_query_data *query, *prev;
#ifndef CONFIG_NO_RADIUS
hostapd_acl_cache_free(hapd->acl_cache);
hapd->acl_cache = NULL;
#endif /* CONFIG_NO_RADIUS */
query = hapd->acl_queries;
hapd->acl_queries = NULL;
while (query) {
prev = query;
query = query->next;
hostapd_acl_query_free(prev);
}
}
void hostapd_free_psk_list(struct hostapd_sta_wpa_psk_short *psk)
{
if (psk && psk->ref) {
/* This will be freed when the last reference is dropped. */
psk->ref--;
return;
}
while (psk) {
struct hostapd_sta_wpa_psk_short *prev = psk;
psk = psk->next;
os_free(prev);
}
}