xref: /freebsd/sys/net80211/ieee80211_monitor.c (revision 71e8eac4fd89dedbcb4130379add151d3ed942fa)
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_var.h>
52 #include <net/if_media.h>
53 #include <net/if_llc.h>
54 #include <net/ethernet.h>
55 
56 #include <net/bpf.h>
57 
58 #include <net80211/ieee80211_var.h>
59 #include <net80211/ieee80211_monitor.h>
60 
61 static void monitor_vattach(struct ieee80211vap *);
62 static int monitor_newstate(struct ieee80211vap *, enum ieee80211_state, int);
63 static int monitor_input(struct ieee80211_node *ni, struct mbuf *m,
64 	const struct ieee80211_rx_stats *rxs, int rssi, int nf);
65 
66 void
67 ieee80211_monitor_attach(struct ieee80211com *ic)
68 {
69 	ic->ic_vattach[IEEE80211_M_MONITOR] = monitor_vattach;
70 }
71 
72 void
73 ieee80211_monitor_detach(struct ieee80211com *ic)
74 {
75 }
76 
77 static void
78 monitor_vdetach(struct ieee80211vap *vap)
79 {
80 }
81 
82 static void
83 monitor_vattach(struct ieee80211vap *vap)
84 {
85 	vap->iv_newstate = monitor_newstate;
86 	vap->iv_input = monitor_input;
87 	vap->iv_opdetach = monitor_vdetach;
88 }
89 
90 /*
91  * IEEE80211_M_MONITOR vap state machine handler.
92  */
93 static int
94 monitor_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
95 {
96 	struct ieee80211com *ic = vap->iv_ic;
97 	enum ieee80211_state ostate;
98 
99 	IEEE80211_LOCK_ASSERT(ic);
100 
101 	ostate = vap->iv_state;
102 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
103 	    __func__, ieee80211_state_name[ostate],
104 	    ieee80211_state_name[nstate], arg);
105 	vap->iv_state = nstate;			/* state transition */
106 	if (nstate == IEEE80211_S_RUN) {
107 		switch (ostate) {
108 		case IEEE80211_S_INIT:
109 			ieee80211_create_ibss(vap, ic->ic_curchan);
110 			break;
111 		default:
112 			break;
113 		}
114 		/*
115 		 * NB: this shouldn't be here but many people use
116 		 * monitor mode for raw packets; once we switch
117 		 * them over to adhoc demo mode remove this.
118 		 */
119 		ieee80211_node_authorize(vap->iv_bss);
120 	}
121 	return 0;
122 }
123 
124 /*
125  * Process a received frame in monitor mode.
126  */
127 static int
128 monitor_input(struct ieee80211_node *ni, struct mbuf *m,
129     const struct ieee80211_rx_stats *rxs, int rssi, int nf)
130 {
131 	struct ieee80211vap *vap = ni->ni_vap;
132 	struct ifnet *ifp = vap->iv_ifp;
133 
134 	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
135 
136 	if (ieee80211_radiotap_active_vap(vap))
137 		ieee80211_radiotap_rx(vap, m);
138 	m_freem(m);
139 	return -1;
140 }
141