freebsd-dev/contrib/hostapd/ieee802_11_auth.c
2005-06-05 22:35:03 +00:00

448 lines
11 KiB
C

/*
* Host AP (software wireless LAN access point) user space daemon for
* Host AP kernel driver / IEEE 802.11 authentication (ACL)
* Copyright (c) 2003-2005, 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 <string.h>
#include <time.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include "hostapd.h"
#include "ieee802_11.h"
#include "ieee802_11_auth.h"
#include "radius.h"
#include "radius_client.h"
#include "eloop.h"
#define RADIUS_ACL_TIMEOUT 30
struct hostapd_cached_radius_acl {
time_t timestamp;
macaddr addr;
int accepted; /* HOSTAPD_ACL_* */
struct hostapd_cached_radius_acl *next;
u32 session_timeout;
u32 acct_interim_interval;
};
struct hostapd_acl_query_data {
time_t 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;
};
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;
free(prev);
}
}
static int hostapd_acl_cache_get(struct hostapd_data *hapd, u8 *addr,
u32 *session_timeout,
u32 *acct_interim_interval)
{
struct hostapd_cached_radius_acl *entry;
time_t now;
time(&now);
entry = hapd->acl_cache;
while (entry) {
if (memcmp(entry->addr, addr, ETH_ALEN) == 0) {
if (now - entry->timestamp > RADIUS_ACL_TIMEOUT)
return -1; /* entry has expired */
if (entry->accepted == HOSTAPD_ACL_ACCEPT_TIMEOUT)
*session_timeout = entry->session_timeout;
*acct_interim_interval = entry->acct_interim_interval;
return entry->accepted;
}
entry = entry->next;
}
return -1;
}
static void hostapd_acl_query_free(struct hostapd_acl_query_data *query)
{
if (query == NULL)
return;
free(query->auth_msg);
free(query);
}
static int hostapd_radius_acl_query(hostapd *hapd, 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;
radius_msg_make_authenticator(msg, addr, ETH_ALEN);
snprintf(buf, sizeof(buf), RADIUS_ADDR_FORMAT, MAC2STR(addr));
if (!radius_msg_add_attr(msg, RADIUS_ATTR_USER_NAME, (u8 *) buf,
strlen(buf))) {
printf("Could not add User-Name\n");
goto fail;
}
if (!radius_msg_add_attr_user_password(
msg, (u8 *) buf, strlen(buf),
hapd->conf->auth_server->shared_secret,
hapd->conf->auth_server->shared_secret_len)) {
printf("Could not add User-Password\n");
goto fail;
}
if (!radius_msg_add_attr(msg, RADIUS_ATTR_NAS_IP_ADDRESS,
(u8 *) &hapd->conf->own_ip_addr, 4)) {
printf("Could not add NAS-IP-Address\n");
goto fail;
}
if (hapd->conf->nas_identifier &&
!radius_msg_add_attr(msg, RADIUS_ATTR_NAS_IDENTIFIER,
(u8 *) hapd->conf->nas_identifier,
strlen(hapd->conf->nas_identifier))) {
printf("Could not add NAS-Identifier\n");
goto fail;
}
snprintf(buf, sizeof(buf), RADIUS_802_1X_ADDR_FORMAT ":%s",
MAC2STR(hapd->own_addr), hapd->conf->ssid);
if (!radius_msg_add_attr(msg, RADIUS_ATTR_CALLED_STATION_ID,
(u8 *) buf, strlen(buf))) {
printf("Could not add Called-Station-Id\n");
goto fail;
}
snprintf(buf, sizeof(buf), RADIUS_802_1X_ADDR_FORMAT,
MAC2STR(addr));
if (!radius_msg_add_attr(msg, RADIUS_ATTR_CALLING_STATION_ID,
(u8 *) buf, strlen(buf))) {
printf("Could not add Calling-Station-Id\n");
goto fail;
}
if (!radius_msg_add_attr_int32(msg, RADIUS_ATTR_NAS_PORT_TYPE,
RADIUS_NAS_PORT_TYPE_IEEE_802_11)) {
printf("Could not add NAS-Port-Type\n");
goto fail;
}
snprintf(buf, sizeof(buf), "CONNECT 11Mbps 802.11b");
if (!radius_msg_add_attr(msg, RADIUS_ATTR_CONNECT_INFO,
(u8 *) buf, strlen(buf))) {
printf("Could not add Connect-Info\n");
goto fail;
}
radius_client_send(hapd->radius, msg, RADIUS_AUTH, addr);
return 0;
fail:
radius_msg_free(msg);
free(msg);
return -1;
}
int hostapd_allowed_address(hostapd *hapd, u8 *addr, u8 *msg, size_t len,
u32 *session_timeout, u32 *acct_interim_interval)
{
*session_timeout = 0;
*acct_interim_interval = 0;
if (hostapd_maclist_found(hapd->conf->accept_mac,
hapd->conf->num_accept_mac, addr))
return HOSTAPD_ACL_ACCEPT;
if (hostapd_maclist_found(hapd->conf->deny_mac,
hapd->conf->num_deny_mac, addr))
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;
if (hapd->conf->macaddr_acl == USE_EXTERNAL_RADIUS_AUTH) {
struct hostapd_acl_query_data *query;
/* Check whether ACL cache has an entry for this station */
int res = hostapd_acl_cache_get(hapd, addr, session_timeout,
acct_interim_interval);
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 (memcmp(query->addr, addr, ETH_ALEN) == 0) {
/* pending query in RADIUS retransmit queue;
* do not generate a new one */
return HOSTAPD_ACL_PENDING;
}
query = query->next;
}
if (!hapd->conf->auth_server)
return HOSTAPD_ACL_REJECT;
/* No entry in the cache - query external RADIUS server */
query = malloc(sizeof(*query));
if (query == NULL) {
printf("malloc for query data failed\n");
return HOSTAPD_ACL_REJECT;
}
memset(query, 0, sizeof(*query));
time(&query->timestamp);
memcpy(query->addr, addr, ETH_ALEN);
if (hostapd_radius_acl_query(hapd, addr, query)) {
printf("Failed to send Access-Request for ACL "
"query.\n");
hostapd_acl_query_free(query);
return HOSTAPD_ACL_REJECT;
}
query->auth_msg = malloc(len);
if (query->auth_msg == NULL) {
printf("Failed to allocate memory for auth frame.\n");
hostapd_acl_query_free(query);
return HOSTAPD_ACL_REJECT;
}
memcpy(query->auth_msg, msg, len);
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;
}
return HOSTAPD_ACL_REJECT;
}
static void hostapd_acl_expire_cache(hostapd *hapd, time_t now)
{
struct hostapd_cached_radius_acl *prev, *entry, *tmp;
prev = NULL;
entry = hapd->acl_cache;
while (entry) {
if (now - entry->timestamp > RADIUS_ACL_TIMEOUT) {
HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL,
"Cached ACL entry for " MACSTR
" has expired.\n", MAC2STR(entry->addr));
if (prev)
prev->next = entry->next;
else
hapd->acl_cache = entry->next;
tmp = entry;
entry = entry->next;
free(tmp);
continue;
}
prev = entry;
entry = entry->next;
}
}
static void hostapd_acl_expire_queries(hostapd *hapd, time_t now)
{
struct hostapd_acl_query_data *prev, *entry, *tmp;
prev = NULL;
entry = hapd->acl_queries;
while (entry) {
if (now - entry->timestamp > RADIUS_ACL_TIMEOUT) {
HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL,
"ACL query for " MACSTR
" has expired.\n", 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;
}
}
static void hostapd_acl_expire(void *eloop_ctx, void *timeout_ctx)
{
hostapd *hapd = eloop_ctx;
time_t now;
time(&now);
hostapd_acl_expire_cache(hapd, now);
hostapd_acl_expire_queries(hapd, now);
eloop_register_timeout(10, 0, hostapd_acl_expire, hapd, NULL);
}
/* Return 0 if RADIUS message was a reply to ACL query (and was processed here)
* or -1 if not. */
static RadiusRxResult
hostapd_acl_recv_radius(struct radius_msg *msg, struct radius_msg *req,
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;
query = hapd->acl_queries;
prev = NULL;
while (query) {
if (query->radius_id == msg->hdr->identifier)
break;
prev = query;
query = query->next;
}
if (query == NULL)
return RADIUS_RX_UNKNOWN;
HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Found matching Access-Request "
"for RADIUS message (id=%d)\n", query->radius_id);
if (radius_msg_verify_acct(msg, shared_secret, shared_secret_len,
req)) {
printf("Incoming RADIUS packet did not have correct "
"authenticator - dropped\n");
return RADIUS_RX_INVALID_AUTHENTICATOR;
}
if (msg->hdr->code != RADIUS_CODE_ACCESS_ACCEPT &&
msg->hdr->code != RADIUS_CODE_ACCESS_REJECT) {
printf("Unknown RADIUS message code %d to ACL query\n",
msg->hdr->code);
return RADIUS_RX_UNKNOWN;
}
/* Insert Accept/Reject info into ACL cache */
cache = malloc(sizeof(*cache));
if (cache == NULL) {
printf("Failed to add ACL cache entry\n");
goto done;
}
memset(cache, 0, sizeof(*cache));
time(&cache->timestamp);
memcpy(cache->addr, query->addr, sizeof(cache->addr));
if (msg->hdr->code == RADIUS_CODE_ACCESS_ACCEPT) {
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) {
HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Ignored too "
"small Acct-Interim-Interval %d for "
"STA " MACSTR "\n",
cache->acct_interim_interval,
MAC2STR(query->addr));
cache->acct_interim_interval = 0;
}
} else
cache->accepted = HOSTAPD_ACL_REJECT;
cache->next = hapd->acl_cache;
hapd->acl_cache = cache;
/* Re-send original authentication frame for 802.11 processing */
HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Re-sending authentication frame "
"after successful RADIUS ACL query\n");
ieee802_11_mgmt(hapd, query->auth_msg, query->auth_msg_len,
WLAN_FC_STYPE_AUTH);
done:
if (prev == NULL)
hapd->acl_queries = query->next;
else
prev->next = query->next;
hostapd_acl_query_free(query);
return RADIUS_RX_PROCESSED;
}
int hostapd_acl_init(hostapd *hapd)
{
if (radius_client_register(hapd->radius, RADIUS_AUTH,
hostapd_acl_recv_radius, hapd))
return -1;
eloop_register_timeout(10, 0, hostapd_acl_expire, hapd, NULL);
return 0;
}
void hostapd_acl_deinit(hostapd *hapd)
{
struct hostapd_acl_query_data *query, *prev;
hostapd_acl_cache_free(hapd->acl_cache);
query = hapd->acl_queries;
while (query) {
prev = query;
query = query->next;
hostapd_acl_query_free(prev);
}
}