1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2006 Shteryana Shopova <syrinx@FreeBSD.org>
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 AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * Bridge MIB implementation for SNMPd.
29  *
30  * $FreeBSD$
31  */
32 
33 #include <sys/param.h>
34 #include <sys/queue.h>
35 #include <sys/socket.h>
36 #include <sys/types.h>
37 
38 #include <net/ethernet.h>
39 #include <net/if.h>
40 #include <net/if_mib.h>
41 #include <net/if_types.h>
42 
43 #include <errno.h>
44 #include <stdarg.h>
45 #include <stdlib.h>
46 #include <stdio.h>
47 #include <string.h>
48 #include <syslog.h>
49 
50 #include <bsnmp/snmpmod.h>
51 #include <bsnmp/snmp_mibII.h>
52 
53 #define	SNMPTREE_TYPES
54 #include "bridge_tree.h"
55 #include "bridge_snmp.h"
56 #include "bridge_oid.h"
57 
58 static struct lmodule *bridge_module;
59 
60 /* For the registration. */
61 static const struct asn_oid oid_dot1Bridge = OIDX_dot1dBridge;
62 /* The registration. */
63 static uint reg_bridge;
64 
65 /* Periodic timer for polling all bridges' data. */
66 static void *bridge_data_timer;
67 static void *bridge_tc_timer;
68 
69 static int bridge_data_maxage = SNMP_BRIDGE_DATA_MAXAGE;
70 static int bridge_poll_ticks = SNMP_BRIDGE_POLL_INTERVAL * 100;
71 static int bridge_tc_poll_ticks = SNMP_BRIDGE_TC_POLL_INTERVAL * 100;
72 
73 /*
74  * Our default bridge, whose info will be visible under
75  * the dot1dBridge subtree and functions to set/fetch it.
76  */
77 static char bif_default_name[IFNAMSIZ] = "bridge0";
78 static struct bridge_if *bif_default;
79 
80 struct bridge_if *
81 bridge_get_default(void)
82 {
83 	struct mibif *ifp;
84 
85 	if (bif_default != NULL) {
86 
87 		/* Walk through the mibII interface list. */
88 		for (ifp = mib_first_if(); ifp != NULL; ifp = mib_next_if(ifp))
89 			if (strcmp(ifp->name, bif_default->bif_name) == 0)
90 				break;
91 
92 		if (ifp == NULL)
93 			bif_default = NULL;
94 	}
95 
96 	return (bif_default);
97 }
98 
99 void
100 bridge_set_default(struct bridge_if *bif)
101 {
102 	bif_default = bif;
103 
104 	syslog(LOG_ERR, "Set default bridge interface to: %s",
105 	    bif == NULL ? "(none)" : bif->bif_name);
106 }
107 
108 const char *
109 bridge_get_default_name(void)
110 {
111 	return (bif_default_name);
112 }
113 
114 static int
115 bridge_set_default_name(const char *bif_name, uint len)
116 {
117 	struct bridge_if *bif;
118 
119 	if (len >= IFNAMSIZ)
120 		return (-1);
121 
122 	bcopy(bif_name, bif_default_name, len);
123 	bif_default_name[len] = '\0';
124 
125 	if ((bif = bridge_if_find_ifname(bif_default_name)) == NULL) {
126 		bif_default = NULL;
127 		return (0);
128 	}
129 
130 	bif_default = bif;
131 	return (1);
132 }
133 
134 int
135 bridge_get_data_maxage(void)
136 {
137 	return (bridge_data_maxage);
138 }
139 
140 static void
141 bridge_set_poll_ticks(int poll_ticks)
142 {
143 	if (bridge_data_timer != NULL)
144 		timer_stop(bridge_data_timer);
145 
146 	bridge_poll_ticks = poll_ticks;
147 	bridge_data_timer = timer_start_repeat(bridge_poll_ticks,
148 	    bridge_poll_ticks, bridge_update_all, NULL, bridge_module);
149 }
150 /*
151  * The bridge module configuration via SNMP.
152  */
153 static int
154 bridge_default_name_save(struct snmp_context *ctx, const char *bridge_default)
155 {
156 	if ((ctx->scratch->int1 = strlen(bridge_default)) >= IFNAMSIZ)
157 		return (-1);
158 
159 	if ((ctx->scratch->ptr1 = malloc(IFNAMSIZ)) == NULL)
160 		return (-1);
161 
162 	strncpy(ctx->scratch->ptr1, bridge_default, ctx->scratch->int1);
163 	return (0);
164 }
165 
166 int
167 op_begemot_bridge_config(struct snmp_context *ctx, struct snmp_value *val,
168     uint sub, uint iidx __unused, enum snmp_op op)
169 {
170 	switch (op) {
171 	    case SNMP_OP_GET:
172 		switch (val->var.subs[sub - 1]) {
173 		    case LEAF_begemotBridgeDefaultBridgeIf:
174 			return (string_get(val, bridge_get_default_name(), -1));
175 
176 		    case LEAF_begemotBridgeDataUpdate:
177 			val->v.integer = bridge_data_maxage;
178 			return (SNMP_ERR_NOERROR);
179 
180 		    case LEAF_begemotBridgeDataPoll:
181 			val->v.integer = bridge_poll_ticks / 100;
182 			return (SNMP_ERR_NOERROR);
183 		}
184 		abort();
185 
186 	    case SNMP_OP_GETNEXT:
187 		abort();
188 
189 	    case SNMP_OP_SET:
190 		switch (val->var.subs[sub - 1]) {
191 		    case LEAF_begemotBridgeDefaultBridgeIf:
192 			/*
193 			 * Cannot use string_save() here - requires either
194 			 * a fixed-sized or var-length string - not less
195 			 * than or equal.
196 			 */
197 			if (bridge_default_name_save(ctx,
198 			    bridge_get_default_name()) < 0)
199 				return (SNMP_ERR_RES_UNAVAIL);
200 
201 			if (bridge_set_default_name(val->v.octetstring.octets,
202 			    val->v.octetstring.len) < 0)
203 				return (SNMP_ERR_BADVALUE);
204 			return (SNMP_ERR_NOERROR);
205 
206 		    case LEAF_begemotBridgeDataUpdate:
207 			if (val->v.integer < SNMP_BRIDGE_DATA_MAXAGE_MIN ||
208 			    val->v.integer > SNMP_BRIDGE_DATA_MAXAGE_MAX)
209 				return (SNMP_ERR_WRONG_VALUE);
210 			ctx->scratch->int1 = bridge_data_maxage;
211 			bridge_data_maxage = val->v.integer;
212 			return (SNMP_ERR_NOERROR);
213 
214 		    case LEAF_begemotBridgeDataPoll:
215 			if (val->v.integer < SNMP_BRIDGE_POLL_INTERVAL_MIN ||
216 			    val->v.integer > SNMP_BRIDGE_POLL_INTERVAL_MAX)
217 				return (SNMP_ERR_WRONG_VALUE);
218 			ctx->scratch->int1 = val->v.integer;
219 			return (SNMP_ERR_NOERROR);
220 		}
221 		abort();
222 
223 	    case SNMP_OP_ROLLBACK:
224 		switch (val->var.subs[sub - 1]) {
225 		    case LEAF_begemotBridgeDefaultBridgeIf:
226 			bridge_set_default_name(ctx->scratch->ptr1,
227 			    ctx->scratch->int1);
228 			free(ctx->scratch->ptr1);
229 			break;
230 		    case LEAF_begemotBridgeDataUpdate:
231 			bridge_data_maxage = ctx->scratch->int1;
232 			break;
233 		}
234 		return (SNMP_ERR_NOERROR);
235 
236 	    case SNMP_OP_COMMIT:
237 		switch (val->var.subs[sub - 1]) {
238 		    case LEAF_begemotBridgeDefaultBridgeIf:
239 			free(ctx->scratch->ptr1);
240 			break;
241 		    case LEAF_begemotBridgeDataPoll:
242 			bridge_set_poll_ticks(ctx->scratch->int1 * 100);
243 			break;
244 		}
245 		return (SNMP_ERR_NOERROR);
246 	}
247 
248 	abort();
249 }
250 
251 /*
252  * Bridge mib module initialization hook.
253  * Returns 0 on success, < 0 on error.
254  */
255 static int
256 bridge_init(struct lmodule * mod, int argc __unused, char *argv[] __unused)
257 {
258 	bridge_module = mod;
259 
260 	if (bridge_kmod_load() < 0)
261 		return (-1);
262 
263 	if (bridge_ioctl_init() < 0)
264 		return (-1);
265 
266 	/* Register to get creation messages for bridge interfaces. */
267 	if (mib_register_newif(bridge_attach_newif, bridge_module)) {
268 		syslog(LOG_ERR, "Cannot register newif function: %s",
269 		    strerror(errno));
270 		return (-1);
271 	}
272 
273 	return (0);
274 }
275 
276 /*
277  * Bridge mib module finalization hook.
278  */
279 static int
280 bridge_fini(void)
281 {
282 	mib_unregister_newif(bridge_module);
283 	or_unregister(reg_bridge);
284 
285 	if (bridge_data_timer != NULL) {
286 		timer_stop(bridge_data_timer);
287 		bridge_data_timer = NULL;
288 	}
289 
290 	if (bridge_tc_timer != NULL) {
291 		timer_stop(bridge_tc_timer);
292 		bridge_tc_timer = NULL;
293 	}
294 
295 	bridge_ifs_fini();
296 	bridge_ports_fini();
297 	bridge_addrs_fini();
298 
299 	return (0);
300 }
301 
302 /*
303  * Bridge mib module start operation.
304  */
305 static void
306 bridge_start(void)
307 {
308 	reg_bridge = or_register(&oid_dot1Bridge,
309 	    "The IETF MIB for Bridges (RFC 4188).", bridge_module);
310 
311 	bridge_data_timer = timer_start_repeat(bridge_poll_ticks,
312 	    bridge_poll_ticks, bridge_update_all, NULL, bridge_module);
313 
314 	bridge_tc_timer = timer_start_repeat(bridge_tc_poll_ticks,
315 	    bridge_tc_poll_ticks, bridge_update_tc_time, NULL, bridge_module);
316 }
317 
318 static void
319 bridge_dump(void)
320 {
321 	struct bridge_if *bif;
322 
323 	if ((bif = bridge_get_default()) == NULL)
324 		syslog(LOG_ERR, "Dump: no default bridge interface");
325 	else
326 		syslog(LOG_ERR, "Dump: default bridge interface %s",
327 		     bif->bif_name);
328 
329 	bridge_ifs_dump();
330 	bridge_pf_dump();
331 }
332 
333 const struct snmp_module config = {
334 	.comment = "This module implements the bridge mib (RFC 4188).",
335 	.init =		bridge_init,
336 	.fini =		bridge_fini,
337 	.start =	bridge_start,
338 	.tree =		bridge_ctree,
339 	.dump =		bridge_dump,
340 	.tree_size =	bridge_CTREE_SIZE,
341 };
342