freebsd-skq/sys/net80211/ieee80211_acl.c
Sam Leffler 188757f54c Extend acl support to pass ioctl requests through and use this to
add support for getting the current policy setting and collecting
the list of mac addresses in the acl table.

Submitted by:	Michal Mertl (original version)
MFC after:	2 weeks
2005-08-13 17:31:48 +00:00

354 lines
8.6 KiB
C

/*-
* Copyright (c) 2004-2005 Sam Leffler, Errno Consulting
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* IEEE 802.11 MAC ACL support.
*
* When this module is loaded the sender address of each received
* frame is passed to the iac_check method and the module indicates
* if the frame should be accepted or rejected. If the policy is
* set to ACL_POLICY_OPEN then all frames are accepted w/o checking
* the address. Otherwise, the address is looked up in the database
* and if found the frame is either accepted (ACL_POLICY_ALLOW)
* or rejected (ACL_POLICY_DENT).
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/module.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_media.h>
#include <net/ethernet.h>
#include <net/route.h>
#include <net80211/ieee80211_var.h>
enum {
ACL_POLICY_OPEN = 0, /* open, don't check ACL's */
ACL_POLICY_ALLOW = 1, /* allow traffic from MAC */
ACL_POLICY_DENY = 2, /* deny traffic from MAC */
};
#define ACL_HASHSIZE 32
struct acl {
TAILQ_ENTRY(acl) acl_list;
LIST_ENTRY(acl) acl_hash;
u_int8_t acl_macaddr[IEEE80211_ADDR_LEN];
};
struct aclstate {
acl_lock_t as_lock;
int as_policy;
int as_nacls;
TAILQ_HEAD(, acl) as_list; /* list of all ACL's */
LIST_HEAD(, acl) as_hash[ACL_HASHSIZE];
struct ieee80211com *as_ic;
};
/* simple hash is enough for variation of macaddr */
#define ACL_HASH(addr) \
(((const u_int8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % ACL_HASHSIZE)
MALLOC_DEFINE(M_80211_ACL, "acl", "802.11 station acl");
static int acl_free_all(struct ieee80211com *);
static int
acl_attach(struct ieee80211com *ic)
{
struct aclstate *as;
MALLOC(as, struct aclstate *, sizeof(struct aclstate),
M_80211_ACL, M_NOWAIT | M_ZERO);
if (as == NULL)
return 0;
ACL_LOCK_INIT(as, "acl");
TAILQ_INIT(&as->as_list);
as->as_policy = ACL_POLICY_OPEN;
as->as_ic = ic;
ic->ic_as = as;
return 1;
}
static void
acl_detach(struct ieee80211com *ic)
{
struct aclstate *as = ic->ic_as;
acl_free_all(ic);
ic->ic_as = NULL;
ACL_LOCK_DESTROY(as);
FREE(as, M_DEVBUF);
}
static __inline struct acl *
_find_acl(struct aclstate *as, const u_int8_t *macaddr)
{
struct acl *acl;
int hash;
hash = ACL_HASH(macaddr);
LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) {
if (IEEE80211_ADDR_EQ(acl->acl_macaddr, macaddr))
return acl;
}
return NULL;
}
static void
_acl_free(struct aclstate *as, struct acl *acl)
{
ACL_LOCK_ASSERT(as);
TAILQ_REMOVE(&as->as_list, acl, acl_list);
LIST_REMOVE(acl, acl_hash);
FREE(acl, M_80211_ACL);
as->as_nacls--;
}
static int
acl_check(struct ieee80211com *ic, const u_int8_t mac[IEEE80211_ADDR_LEN])
{
struct aclstate *as = ic->ic_as;
switch (as->as_policy) {
case ACL_POLICY_OPEN:
return 1;
case ACL_POLICY_ALLOW:
return _find_acl(as, mac) != NULL;
case ACL_POLICY_DENY:
return _find_acl(as, mac) == NULL;
}
return 0; /* should not happen */
}
static int
acl_add(struct ieee80211com *ic, const u_int8_t mac[IEEE80211_ADDR_LEN])
{
struct aclstate *as = ic->ic_as;
struct acl *acl, *new;
int hash;
MALLOC(new, struct acl *, sizeof(struct acl), M_80211_ACL, M_NOWAIT | M_ZERO);
if (new == NULL) {
IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
"ACL: add %s failed, no memory\n", ether_sprintf(mac));
/* XXX statistic */
return ENOMEM;
}
ACL_LOCK(as);
hash = ACL_HASH(mac);
LIST_FOREACH(acl, &as->as_hash[hash], acl_hash) {
if (IEEE80211_ADDR_EQ(acl->acl_macaddr, mac)) {
ACL_UNLOCK(as);
FREE(new, M_80211_ACL);
IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
"ACL: add %s failed, already present\n",
ether_sprintf(mac));
return EEXIST;
}
}
IEEE80211_ADDR_COPY(new->acl_macaddr, mac);
TAILQ_INSERT_TAIL(&as->as_list, new, acl_list);
LIST_INSERT_HEAD(&as->as_hash[hash], new, acl_hash);
as->as_nacls++;
ACL_UNLOCK(as);
IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
"ACL: add %s\n", ether_sprintf(mac));
return 0;
}
static int
acl_remove(struct ieee80211com *ic, const u_int8_t mac[IEEE80211_ADDR_LEN])
{
struct aclstate *as = ic->ic_as;
struct acl *acl;
ACL_LOCK(as);
acl = _find_acl(as, mac);
if (acl != NULL)
_acl_free(as, acl);
ACL_UNLOCK(as);
IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
"ACL: remove %s%s\n", ether_sprintf(mac),
acl == NULL ? ", not present" : "");
return (acl == NULL ? ENOENT : 0);
}
static int
acl_free_all(struct ieee80211com *ic)
{
struct aclstate *as = ic->ic_as;
struct acl *acl;
IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL, "ACL: %s\n", "free all");
ACL_LOCK(as);
while ((acl = TAILQ_FIRST(&as->as_list)) != NULL)
_acl_free(as, acl);
ACL_UNLOCK(as);
return 0;
}
static int
acl_setpolicy(struct ieee80211com *ic, int policy)
{
struct aclstate *as = ic->ic_as;
IEEE80211_DPRINTF(ic, IEEE80211_MSG_ACL,
"ACL: set policy to %u\n", policy);
switch (policy) {
case IEEE80211_MACCMD_POLICY_OPEN:
as->as_policy = ACL_POLICY_OPEN;
break;
case IEEE80211_MACCMD_POLICY_ALLOW:
as->as_policy = ACL_POLICY_ALLOW;
break;
case IEEE80211_MACCMD_POLICY_DENY:
as->as_policy = ACL_POLICY_DENY;
break;
default:
return EINVAL;
}
return 0;
}
static int
acl_getpolicy(struct ieee80211com *ic)
{
struct aclstate *as = ic->ic_as;
return as->as_policy;
}
static int
acl_setioctl(struct ieee80211com *ic, struct ieee80211req *ireq)
{
return EINVAL;
}
static int
acl_getioctl(struct ieee80211com *ic, struct ieee80211req *ireq)
{
struct aclstate *as = ic->ic_as;
struct acl *acl;
struct ieee80211req_maclist *ap;
int error, space, i;
switch (ireq->i_val) {
case IEEE80211_MACCMD_POLICY:
ireq->i_val = as->as_policy;
return 0;
case IEEE80211_MACCMD_LIST:
space = as->as_nacls * IEEE80211_ADDR_LEN;
if (ireq->i_len == 0) {
ireq->i_len = space; /* return required space */
return 0; /* NB: must not error */
}
MALLOC(ap, struct ieee80211req_maclist *, space,
M_TEMP, M_NOWAIT);
if (ap == NULL)
return ENOMEM;
i = 0;
ACL_LOCK(as);
TAILQ_FOREACH(acl, &as->as_list, acl_list) {
IEEE80211_ADDR_COPY(ap[i].ml_macaddr, acl->acl_macaddr);
i++;
}
ACL_UNLOCK(as);
if (ireq->i_len >= space) {
error = copyout(ap, ireq->i_data, space);
ireq->i_len = space;
} else
error = copyout(ap, ireq->i_data, ireq->i_len);
FREE(ap, M_TEMP);
return error;
}
return EINVAL;
}
static const struct ieee80211_aclator mac = {
.iac_name = "mac",
.iac_attach = acl_attach,
.iac_detach = acl_detach,
.iac_check = acl_check,
.iac_add = acl_add,
.iac_remove = acl_remove,
.iac_flush = acl_free_all,
.iac_setpolicy = acl_setpolicy,
.iac_getpolicy = acl_getpolicy,
.iac_setioctl = acl_setioctl,
.iac_getioctl = acl_getioctl,
};
/*
* Module glue.
*/
static int
wlan_acl_modevent(module_t mod, int type, void *unused)
{
switch (type) {
case MOD_LOAD:
if (bootverbose)
printf("wlan: <802.11 MAC ACL support>\n");
ieee80211_aclator_register(&mac);
return 0;
case MOD_UNLOAD:
ieee80211_aclator_unregister(&mac);
return 0;
}
return EINVAL;
}
static moduledata_t wlan_acl_mod = {
"wlan_acl",
wlan_acl_modevent,
0
};
DECLARE_MODULE(wlan_acl, wlan_acl_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
MODULE_VERSION(wlan_acl, 1);
MODULE_DEPEND(wlan_acl, wlan, 1, 1, 1);