1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29#ifdef __FreeBSD__
30__FBSDID("$FreeBSD: releng/12.0/sys/net80211/ieee80211_monitor.c 326272 2017-11-27 15:23:17Z pfg $");
31#endif
32
33/*
34 * IEEE 802.11 Monitor mode support.
35 */
36#include "opt_inet.h"
37#include "opt_wlan.h"
38
39#include <sys/param.h>
40#include <sys/systm.h>
41#include <sys/mbuf.h>
42#include <sys/malloc.h>
43#include <sys/kernel.h>
44
45#include <sys/socket.h>
46#include <sys/sockio.h>
47#include <sys/endian.h>
48#include <sys/errno.h>
49#include <sys/proc.h>
50#include <sys/sysctl.h>
51
52#include <net/if.h>
53#include <net/if_var.h>
54#include <net/if_media.h>
55#include <net/if_llc.h>
56#include <net/ethernet.h>
57
58#include <net/bpf.h>
59
60#include <net80211/ieee80211_var.h>
61#include <net80211/ieee80211_monitor.h>
62
63static void monitor_vattach(struct ieee80211vap *);
64static int monitor_newstate(struct ieee80211vap *, enum ieee80211_state, int);
65static int monitor_input(struct ieee80211_node *ni, struct mbuf *m,
66	const struct ieee80211_rx_stats *rxs, int rssi, int nf);
67
68void
69ieee80211_monitor_attach(struct ieee80211com *ic)
70{
71	ic->ic_vattach[IEEE80211_M_MONITOR] = monitor_vattach;
72}
73
74void
75ieee80211_monitor_detach(struct ieee80211com *ic)
76{
77}
78
79static void
80monitor_vdetach(struct ieee80211vap *vap)
81{
82}
83
84static void
85monitor_vattach(struct ieee80211vap *vap)
86{
87	vap->iv_newstate = monitor_newstate;
88	vap->iv_input = monitor_input;
89	vap->iv_opdetach = monitor_vdetach;
90}
91
92/*
93 * IEEE80211_M_MONITOR vap state machine handler.
94 */
95static int
96monitor_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
97{
98	struct ieee80211com *ic = vap->iv_ic;
99	enum ieee80211_state ostate;
100
101	IEEE80211_LOCK_ASSERT(ic);
102
103	ostate = vap->iv_state;
104	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
105	    __func__, ieee80211_state_name[ostate],
106	    ieee80211_state_name[nstate], arg);
107	vap->iv_state = nstate;			/* state transition */
108	if (nstate == IEEE80211_S_RUN) {
109		switch (ostate) {
110		case IEEE80211_S_INIT:
111			ieee80211_create_ibss(vap, ic->ic_curchan);
112			break;
113		default:
114			break;
115		}
116		/*
117		 * NB: this shouldn't be here but many people use
118		 * monitor mode for raw packets; once we switch
119		 * them over to adhoc demo mode remove this.
120		 */
121		ieee80211_node_authorize(vap->iv_bss);
122	}
123	return 0;
124}
125
126/*
127 * Process a received frame in monitor mode.
128 */
129static int
130monitor_input(struct ieee80211_node *ni, struct mbuf *m,
131    const struct ieee80211_rx_stats *rxs, int rssi, int nf)
132{
133	struct ieee80211vap *vap = ni->ni_vap;
134	struct ifnet *ifp = vap->iv_ifp;
135
136	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
137
138	if (ieee80211_radiotap_active_vap(vap))
139		ieee80211_radiotap_rx(vap, m);
140	m_freem(m);
141	return -1;
142}
143