xref: /freebsd/sys/net80211/ieee80211_monitor.c (revision 9a14aa017b21c292740c00ee098195cd46642730)
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("$FreeBSD$");
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 
60 static void monitor_vattach(struct ieee80211vap *);
61 static int monitor_newstate(struct ieee80211vap *, enum ieee80211_state, int);
62 static int monitor_input(struct ieee80211_node *ni, struct mbuf *m,
63 	int rssi, int nf);
64 
65 void
66 ieee80211_monitor_attach(struct ieee80211com *ic)
67 {
68 	ic->ic_vattach[IEEE80211_M_MONITOR] = monitor_vattach;
69 }
70 
71 void
72 ieee80211_monitor_detach(struct ieee80211com *ic)
73 {
74 }
75 
76 static void
77 monitor_vdetach(struct ieee80211vap *vap)
78 {
79 }
80 
81 static void
82 monitor_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  */
92 static int
93 monitor_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  */
126 static int
127 monitor_input(struct ieee80211_node *ni, struct mbuf *m, int rssi, int nf)
128 {
129 	struct ieee80211vap *vap = ni->ni_vap;
130 	struct ifnet *ifp = vap->iv_ifp;
131 
132 	ifp->if_ipackets++;
133 
134 	if (ieee80211_radiotap_active_vap(vap))
135 		ieee80211_radiotap_rx(vap, m);
136 	m_freem(m);
137 	return -1;
138 }
139