ieee80211_monitor.c revision 178354 
1/*-
2 * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include <sys/cdefs.h>
27#ifdef __FreeBSD__
28__FBSDID("$FreeBSD: head/sys/net80211/ieee80211_monitor.c 178354 2008-04-20 20:35:46Z sam $");
29#endif
30
31/*
32 * IEEE 802.11 Monitor mode support.
33 */
34#include "opt_inet.h"
35#include "opt_wlan.h"
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/mbuf.h>
40#include <sys/malloc.h>
41#include <sys/kernel.h>
42
43#include <sys/socket.h>
44#include <sys/sockio.h>
45#include <sys/endian.h>
46#include <sys/errno.h>
47#include <sys/proc.h>
48#include <sys/sysctl.h>
49
50#include <net/if.h>
51#include <net/if_media.h>
52#include <net/if_llc.h>
53#include <net/ethernet.h>
54
55#include <net/bpf.h>
56
57#include <net80211/ieee80211_var.h>
58#include <net80211/ieee80211_monitor.h>
59
60static void monitor_vattach(struct ieee80211vap *);
61static int monitor_newstate(struct ieee80211vap *, enum ieee80211_state, int);
62static int monitor_input(struct ieee80211_node *ni, struct mbuf *m,
63	int rssi, int noise, uint32_t rstamp);
64
65void
66ieee80211_monitor_attach(struct ieee80211com *ic)
67{
68	ic->ic_vattach[IEEE80211_M_MONITOR] = monitor_vattach;
69}
70
71void
72ieee80211_monitor_detach(struct ieee80211com *ic)
73{
74}
75
76static void
77monitor_vdetach(struct ieee80211vap *vap)
78{
79}
80
81static void
82monitor_vattach(struct ieee80211vap *vap)
83{
84	vap->iv_newstate = monitor_newstate;
85	vap->iv_input = monitor_input;
86	vap->iv_opdetach = monitor_vdetach;
87}
88
89/*
90 * IEEE80211_M_MONITOR vap state machine handler.
91 */
92static int
93monitor_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
94{
95	struct ieee80211com *ic = vap->iv_ic;
96	enum ieee80211_state ostate;
97
98	IEEE80211_LOCK_ASSERT(ic);
99
100	ostate = vap->iv_state;
101	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
102	    __func__, ieee80211_state_name[ostate],
103	    ieee80211_state_name[nstate], arg);
104	vap->iv_state = nstate;			/* state transition */
105	if (nstate == IEEE80211_S_RUN) {
106		switch (ostate) {
107		case IEEE80211_S_INIT:
108			ieee80211_create_ibss(vap, ic->ic_curchan);
109			break;
110		default:
111			break;
112		}
113		/*
114		 * NB: this shouldn't be here but many people use
115		 * monitor mode for raw packets; once we switch
116		 * them over to adhoc demo mode remove this.
117		 */
118		ieee80211_node_authorize(vap->iv_bss);
119	}
120	return 0;
121}
122
123/*
124 * Process a received frame in monitor mode.
125 */
126static int
127monitor_input(struct ieee80211_node *ni, struct mbuf *m,
128	int rssi, int noise, uint32_t rstamp)
129{
130	struct ieee80211vap *vap = ni->ni_vap;
131
132	if (bpf_peers_present(vap->iv_rawbpf))
133		bpf_mtap(vap->iv_rawbpf, m);
134	m_freem(m);
135	return -1;
136}
137