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