xref: /freebsd/sys/dev/wtap/plugins/visibility.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2010-2011 Monthadar Al Jaberi, TerraNet AB
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  *    without modification.
13  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
14  *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
15  *    redistribution must be conditioned upon including a substantially
16  *    similar Disclaimer requirement for further binary redistribution.
17  *
18  * NO WARRANTY
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
22  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
23  * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
24  * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
27  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
29  * THE POSSIBILITY OF SUCH DAMAGES.
30  *
31  * $FreeBSD$
32  */
33 #include <sys/param.h>
34 #include <sys/module.h>
35 #include <sys/kernel.h>
36 #include <sys/systm.h>
37 #include <sys/sysctl.h>
38 #include <sys/mbuf.h>
39 #include <sys/malloc.h>
40 #include <sys/lock.h>
41 #include <sys/mutex.h>
42 #include <sys/proc.h>
43 #include <sys/ucred.h>
44 #include <sys/jail.h>
45 
46 #include <sys/sockio.h>
47 #include <sys/socket.h>
48 #include <sys/socketvar.h>
49 #include <sys/errno.h>
50 #include <sys/callout.h>
51 #include <sys/endian.h>
52 #include <sys/kthread.h>
53 #include <sys/taskqueue.h>
54 #include <sys/priv.h>
55 #include <sys/sysctl.h>
56 
57 #include <machine/bus.h>
58 
59 #include <net/if.h>
60 #include <net/if_dl.h>
61 #include <net/if_media.h>
62 #include <net/if_types.h>
63 #include <net/if_arp.h>
64 #include <net/ethernet.h>
65 #include <net/if_llc.h>
66 #include <net/vnet.h>
67 
68 #include <net80211/ieee80211_var.h>
69 #include <net80211/ieee80211_regdomain.h>
70 
71 #include <net/bpf.h>
72 
73 #include <sys/errno.h>
74 #include <sys/conf.h>   /* cdevsw struct */
75 #include <sys/uio.h>    /* uio struct */
76 
77 #include <netinet/in.h>
78 #include <netinet/if_ether.h>
79 
80 #include "visibility.h"
81 
82 /* Function prototypes */
83 static d_ioctl_t	vis_ioctl;
84 
85 static struct cdevsw vis_cdevsw = {
86 	.d_version =	D_VERSION,
87 	.d_flags =	0,
88 	.d_ioctl =	vis_ioctl,
89 	.d_name =	"visctl",
90 };
91 
92 void
93 visibility_init(struct wtap_plugin *plugin)
94 {
95 	struct visibility_plugin *vis_plugin;
96 
97 	vis_plugin = (struct visibility_plugin *) plugin;
98 	plugin->wp_sdev = make_dev(&vis_cdevsw,0,UID_ROOT,GID_WHEEL,0600,
99 	    (const char *)"visctl");
100 	plugin->wp_sdev->si_drv1 = vis_plugin;
101 	mtx_init(&vis_plugin->pl_mtx, "visibility_plugin mtx",
102 	    NULL, MTX_DEF | MTX_RECURSE);
103 	printf("Using visibility wtap plugin...\n");
104 }
105 
106 void
107 visibility_deinit(struct wtap_plugin *plugin)
108 {
109 	struct visibility_plugin *vis_plugin;
110 
111 	vis_plugin = (struct visibility_plugin *) plugin;
112 	destroy_dev(plugin->wp_sdev);
113 	mtx_destroy(&vis_plugin->pl_mtx);
114 	free(vis_plugin, M_WTAP_PLUGIN);
115 	printf("Removing visibility wtap plugin...\n");
116 }
117 
118 /* We need to use a mutex lock when we read out a visibility map
119  * and when we change visibility map from user space through IOCTL
120  */
121 void
122 visibility_work(struct wtap_plugin *plugin, struct packet *p)
123 {
124 	struct visibility_plugin *vis_plugin =
125 	    (struct visibility_plugin *) plugin;
126 	struct wtap_hal *hal = (struct wtap_hal *)vis_plugin->base.wp_hal;
127 	struct vis_map *map;
128 
129 	KASSERT(mtod(p->m, const char *) != (const char *) 0xdeadc0de ||
130 	    mtod(p->m, const char *) != NULL,
131 	    ("[%s] got a corrupt packet from master queue, p->m=%p, p->id=%d\n",
132 	    __func__, p->m, p->id));
133 	DWTAP_PRINTF("[%d] BROADCASTING m=%p\n", p->id, p->m);
134 	mtx_lock(&vis_plugin->pl_mtx);
135 	map = &vis_plugin->pl_node[p->id];
136 	mtx_unlock(&vis_plugin->pl_mtx);
137 
138 	/* This is O(n*n) which is not optimal for large
139 	 * number of nodes. Another way of doing it is
140 	 * creating groups of nodes that hear each other.
141 	 * Atleast for this simple static node plugin.
142 	 */
143 	for(int i=0; i<ARRAY_SIZE; ++i){
144 		uint32_t index = map->map[i];
145 		for(int j=0; j<32; ++j){
146 			int vis = index & 0x01;
147 			if(vis){
148 				int k = i*ARRAY_SIZE + j;
149 				if(hal->hal_devs[k] != NULL
150 				    && hal->hal_devs[k]->up == 1){
151 					struct wtap_softc *sc =
152 					    hal->hal_devs[k];
153 					struct mbuf *m =
154 					    m_dup(p->m, M_NOWAIT);
155 					DWTAP_PRINTF("[%d] duplicated old_m=%p"
156 					    "to new_m=%p\n", p->id, p->m, m);
157 #if 0
158 					printf("[%d] sending to %d\n",
159 					    p->id, k);
160 #endif
161 					wtap_inject(sc, m);
162 				}
163 			}
164 			index = index >> 1;
165 		}
166 	}
167 }
168 
169 static void
170 add_link(struct visibility_plugin *vis_plugin, struct link *l)
171 {
172 
173 	mtx_lock(&vis_plugin->pl_mtx);
174 	struct vis_map *map = &vis_plugin->pl_node[l->id1];
175 	int index = l->id2/ARRAY_SIZE;
176 	int bit = l->id2 % ARRAY_SIZE;
177 	uint32_t value = 1 << bit;
178 	map->map[index] = map->map[index] | value;
179 	mtx_unlock(&vis_plugin->pl_mtx);
180 #if 0
181 	printf("l->id1=%d, l->id2=%d, map->map[%d] = %u, bit=%d\n",
182 	    l->id1, l->id2, index, map->map[index], bit);
183 #endif
184 }
185 
186 static void
187 del_link(struct visibility_plugin *vis_plugin, struct link *l)
188 {
189 
190 	mtx_lock(&vis_plugin->pl_mtx);
191 	struct vis_map *map = &vis_plugin->pl_node[l->id1];
192 	int index = l->id2/ARRAY_SIZE;
193 	int bit = l->id2 % ARRAY_SIZE;
194 	uint32_t value = 1 << bit;
195 	map->map[index] = map->map[index] & ~value;
196 	mtx_unlock(&vis_plugin->pl_mtx);
197 #if 0
198 	printf("map->map[index] = %u\n", map->map[index]);
199 #endif
200 }
201 
202 int
203 vis_ioctl(struct cdev *sdev, u_long cmd, caddr_t data,
204     int fflag, struct thread *td)
205 {
206 	struct visibility_plugin *vis_plugin =
207 	    (struct visibility_plugin *) sdev->si_drv1;
208 	struct wtap_hal *hal = vis_plugin->base.wp_hal;
209 	struct link l;
210 	int op;
211 	int error = 0;
212 
213 	CURVNET_SET(CRED_TO_VNET(curthread->td_ucred));
214 	switch(cmd) {
215 	case VISIOCTLOPEN:
216 		op =  *(int *)data;
217 		if(op == 0)
218 			medium_close(hal->hal_md);
219 		else
220 			medium_open(hal->hal_md);
221 		break;
222 	case VISIOCTLLINK:
223 		l = *(struct link *)data;
224 		if(l.op == 0)
225 			del_link(vis_plugin, &l);
226 		else
227 			add_link(vis_plugin, &l);
228 #if 0
229 		printf("op=%d, id1=%d, id2=%d\n", l.op, l.id1, l.id2);
230 #endif
231 		break;
232 	default:
233 		DWTAP_PRINTF("Unknown WTAP IOCTL\n");
234 		error = EINVAL;
235 	}
236 
237 	CURVNET_RESTORE();
238 	return error;
239 }
240