1 files changed, 301 insertions, 0 deletions
diff --git a/sys/net80211/ieee80211_acl.c b/sys/net80211/ieee80211_acl.c
new file mode 100644
index 0000000..e04fa13
--- /dev/null
+++ b/sys/net80211/ieee80211_acl.c
@@ -0,0 +1,301 @@
+/*-
+ * Copyright (c) 2004 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;
+	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_DEVBUF, 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);
+}
+
+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);
+	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 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,
+};
+
+/*
+ * 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);