xref: /freebsd/contrib/bsnmp/snmpd/main.c (revision 8ef24a0d4b28fe230e20637f56869cc4148cd2ca)
1 /*
2  * Copyright (c) 2001-2003
3  *	Fraunhofer Institute for Open Communication Systems (FhG Fokus).
4  *	All rights reserved.
5  *
6  * Author: Harti Brandt <harti@freebsd.org>
7  *
8  * Copyright (c) 2010 The FreeBSD Foundation
9  * All rights reserved.
10  *
11  * Portions of this software were developed by Shteryana Sotirova Shopova
12  * under sponsorship from the FreeBSD Foundation.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  *
23  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  * $Begemot: bsnmp/snmpd/main.c,v 1.100 2006/02/14 09:04:20 brandt_h Exp $
36  *
37  * SNMPd main stuff.
38  */
39 
40 #include <sys/queue.h>
41 #include <sys/param.h>
42 #include <sys/un.h>
43 #include <sys/ucred.h>
44 #include <sys/uio.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <stddef.h>
48 #include <string.h>
49 #include <stdarg.h>
50 #include <ctype.h>
51 #include <errno.h>
52 #include <syslog.h>
53 #include <unistd.h>
54 #include <signal.h>
55 #include <dlfcn.h>
56 #include <inttypes.h>
57 
58 #ifdef USE_TCPWRAPPERS
59 #include <arpa/inet.h>
60 #include <tcpd.h>
61 #endif
62 
63 #include "support.h"
64 #include "snmpmod.h"
65 #include "snmpd.h"
66 #include "tree.h"
67 #include "oid.h"
68 
69 #define	PATH_PID	"/var/run/%s.pid"
70 #define PATH_CONFIG	"/etc/%s.config"
71 #define	PATH_ENGINE	"/var/%s.engine"
72 
73 uint64_t this_tick;	/* start of processing of current packet (absolute) */
74 uint64_t start_tick;	/* start of processing */
75 
76 struct systemg systemg = {
77 	NULL,
78 	{ 8, { 1, 3, 6, 1, 4, 1, 1115, 7352 }},
79 	NULL, NULL, NULL,
80 	64 + 8 + 4,
81 	0
82 };
83 struct debug debug = {
84 	0,		/* dump_pdus */
85 	LOG_DEBUG,	/* log_pri */
86 	0,		/* evdebug */
87 };
88 
89 struct snmpd snmpd = {
90 	2048,		/* txbuf */
91 	2048,		/* rxbuf */
92 	0,		/* comm_dis */
93 	0,		/* auth_traps */
94 	{0, 0, 0, 0},	/* trap1addr */
95 	VERS_ENABLE_ALL,/* version_enable */
96 };
97 struct snmpd_stats snmpd_stats;
98 
99 struct snmpd_usmstat snmpd_usmstats;
100 
101 /* snmpEngine */
102 struct snmp_engine snmpd_engine;
103 
104 /* snmpSerialNo */
105 int32_t snmp_serial_no;
106 
107 struct snmpd_target_stats snmpd_target_stats;
108 
109 /* search path for config files */
110 const char *syspath = PATH_SYSCONFIG;
111 
112 /* list of all loaded modules */
113 struct lmodules lmodules = TAILQ_HEAD_INITIALIZER(lmodules);
114 
115 /* list of loaded modules during start-up in the order they were loaded */
116 static struct lmodules modules_start = TAILQ_HEAD_INITIALIZER(modules_start);
117 
118 /* list of all known communities */
119 struct community_list community_list = TAILQ_HEAD_INITIALIZER(community_list);
120 
121 /* list of all known USM users */
122 static struct usm_userlist usm_userlist = SLIST_HEAD_INITIALIZER(usm_userlist);
123 
124 /* A list of all VACM users configured, including v1, v2c and v3 */
125 static struct vacm_userlist vacm_userlist =
126     SLIST_HEAD_INITIALIZER(vacm_userlist);
127 
128 /* A list of all VACM groups */
129 static struct vacm_grouplist vacm_grouplist =
130     SLIST_HEAD_INITIALIZER(vacm_grouplist);
131 
132 static struct vacm_group vacm_default_group = {
133 	.groupname = "",
134 };
135 
136 /* The list of configured access entries */
137 static struct vacm_accesslist vacm_accesslist =
138     TAILQ_HEAD_INITIALIZER(vacm_accesslist);
139 
140 /* The list of configured views */
141 static struct vacm_viewlist vacm_viewlist =
142     SLIST_HEAD_INITIALIZER(vacm_viewlist);
143 
144 /* The list of configured contexts */
145 static struct vacm_contextlist vacm_contextlist =
146     SLIST_HEAD_INITIALIZER(vacm_contextlist);
147 
148 /* list of all installed object resources */
149 struct objres_list objres_list = TAILQ_HEAD_INITIALIZER(objres_list);
150 
151 /* community value generator */
152 static u_int next_community_index = 1;
153 
154 /* list of all known ranges */
155 struct idrange_list idrange_list = TAILQ_HEAD_INITIALIZER(idrange_list);
156 
157 /* identifier generator */
158 u_int next_idrange = 1;
159 
160 /* list of all current timers */
161 struct timer_list timer_list = LIST_HEAD_INITIALIZER(timer_list);
162 
163 /* list of file descriptors */
164 struct fdesc_list fdesc_list = LIST_HEAD_INITIALIZER(fdesc_list);
165 
166 /* program arguments */
167 static char **progargs;
168 static int nprogargs;
169 
170 /* current community */
171 u_int	community;
172 static struct community *comm;
173 
174 /* current USM user */
175 struct usm_user *usm_user;
176 
177 /* file names */
178 static char config_file[MAXPATHLEN + 1];
179 static char pid_file[MAXPATHLEN + 1];
180 char engine_file[MAXPATHLEN + 1];
181 
182 #ifndef USE_LIBBEGEMOT
183 /* event context */
184 static evContext evctx;
185 #endif
186 
187 /* signal mask */
188 static sigset_t blocked_sigs;
189 
190 /* signal handling */
191 static int work;
192 #define	WORK_DOINFO	0x0001
193 #define	WORK_RECONFIG	0x0002
194 
195 /* oids */
196 static const struct asn_oid
197 	oid_snmpMIB = OIDX_snmpMIB,
198 	oid_begemotSnmpd = OIDX_begemotSnmpd,
199 	oid_coldStart = OIDX_coldStart,
200 	oid_authenticationFailure = OIDX_authenticationFailure;
201 
202 const struct asn_oid oid_zeroDotZero = { 2, { 0, 0 }};
203 
204 const struct asn_oid oid_usmUnknownEngineIDs =
205 	{ 11, { 1, 3, 6, 1, 6, 3, 15, 1, 1, 4, 0}};
206 
207 const struct asn_oid oid_usmNotInTimeWindows =
208 	{ 11, { 1, 3, 6, 1, 6, 3, 15, 1, 1, 2, 0}};
209 
210 /* request id generator for traps */
211 u_int trap_reqid;
212 
213 /* help text */
214 static const char usgtxt[] = "\
215 Begemot simple SNMP daemon. Copyright (c) 2001-2002 Fraunhofer Institute for\n\
216 Open Communication Systems (FhG Fokus). All rights reserved.\n\
217 Copyright (c) 2010 The FreeBSD Foundation. All rights reserved.\n\
218 usage: snmpd [-dh] [-c file] [-D options] [-e file] [-I path]\n\
219              [-l prefix] [-m variable=value] [-p file]\n\
220 options:\n\
221   -d		don't daemonize\n\
222   -h		print this info\n\
223   -c file	specify configuration file\n\
224   -D options	debugging options\n\
225   -e file	specify engine id file\n\
226   -I path	system include path\n\
227   -l prefix	default basename for pid and config file\n\
228   -m var=val	define variable\n\
229   -p file	specify pid file\n\
230 ";
231 
232 /* hosts_access(3) request */
233 #ifdef USE_TCPWRAPPERS
234 static struct request_info req;
235 #endif
236 
237 /* transports */
238 extern const struct transport_def udp_trans;
239 extern const struct transport_def lsock_trans;
240 
241 struct transport_list transport_list = TAILQ_HEAD_INITIALIZER(transport_list);
242 
243 /* forward declarations */
244 static void snmp_printf_func(const char *fmt, ...);
245 static void snmp_error_func(const char *err, ...);
246 static void snmp_debug_func(const char *err, ...);
247 static void asn_error_func(const struct asn_buf *b, const char *err, ...);
248 
249 /*
250  * Allocate rx/tx buffer. We allocate one byte more for rx.
251  */
252 void *
253 buf_alloc(int tx)
254 {
255 	void *buf;
256 
257 	if ((buf = malloc(tx ? snmpd.txbuf : snmpd.rxbuf)) == NULL) {
258 		syslog(LOG_CRIT, "cannot allocate buffer");
259 		if (tx)
260 			snmpd_stats.noTxbuf++;
261 		else
262 			snmpd_stats.noRxbuf++;
263 		return (NULL);
264 	}
265 	return (buf);
266 }
267 
268 /*
269  * Return the buffer size.
270  */
271 size_t
272 buf_size(int tx)
273 {
274 	return (tx ? snmpd.txbuf : snmpd.rxbuf);
275 }
276 
277 /*
278  * Prepare a PDU for output
279  */
280 void
281 snmp_output(struct snmp_pdu *pdu, u_char *sndbuf, size_t *sndlen,
282     const char *dest)
283 {
284 	struct asn_buf resp_b;
285 
286 	resp_b.asn_ptr = sndbuf;
287 	resp_b.asn_len = snmpd.txbuf;
288 
289 	if (snmp_pdu_encode(pdu, &resp_b) != 0) {
290 		syslog(LOG_ERR, "cannot encode message");
291 		abort();
292 	}
293 	if (debug.dump_pdus) {
294 		snmp_printf("%s <- ", dest);
295 		snmp_pdu_dump(pdu);
296 	}
297 	*sndlen = (size_t)(resp_b.asn_ptr - sndbuf);
298 }
299 
300 /*
301  * Check USM PDU header credentials against local SNMP Engine & users.
302  */
303 static enum snmp_code
304 snmp_pdu_auth_user(struct snmp_pdu *pdu)
305 {
306 	uint64_t etime;
307 	usm_user = NULL;
308 
309 	/* un-authenticated snmpEngineId discovery */
310 	if (pdu->engine.engine_len == 0 && strlen(pdu->user.sec_name) == 0) {
311 		pdu->engine.engine_len = snmpd_engine.engine_len;
312 		memcpy(pdu->engine.engine_id, snmpd_engine.engine_id,
313 		    snmpd_engine.engine_len);
314 		pdu->engine.engine_boots = snmpd_engine.engine_boots;
315 		pdu->engine.engine_time = snmpd_engine.engine_time;
316 		pdu->flags |= SNMP_MSG_AUTODISCOVER;
317 		return (SNMP_CODE_OK);
318 	}
319 
320 	if ((usm_user = usm_find_user(pdu->engine.engine_id,
321 	    pdu->engine.engine_len, pdu->user.sec_name)) == NULL ||
322 	    usm_user->status != 1 /* active */)
323 		return (SNMP_CODE_BADUSER);
324 
325 	if (usm_user->user_engine_len != snmpd_engine.engine_len ||
326 	    memcmp(usm_user->user_engine_id, snmpd_engine.engine_id,
327 	    snmpd_engine.engine_len) != 0)
328 		return (SNMP_CODE_BADENGINE);
329 
330 	pdu->user.priv_proto = usm_user->suser.priv_proto;
331 	memcpy(pdu->user.priv_key, usm_user->suser.priv_key,
332 	    sizeof(pdu->user.priv_key));
333 
334 	/* authenticated snmpEngineId discovery */
335 	if ((pdu->flags & SNMP_MSG_AUTH_FLAG) != 0) {
336 		etime = (get_ticks() - start_tick)  / 100ULL;
337 		if (etime < INT32_MAX)
338 			snmpd_engine.engine_time = etime;
339 		else {
340 			start_tick = get_ticks();
341 			set_snmpd_engine();
342 			snmpd_engine.engine_time = start_tick;
343 		}
344 
345 		pdu->user.auth_proto = usm_user->suser.auth_proto;
346 		memcpy(pdu->user.auth_key, usm_user->suser.auth_key,
347 		    sizeof(pdu->user.auth_key));
348 
349 		if (pdu->engine.engine_boots == 0 &&
350 		    pdu->engine.engine_time == 0) {
351 		    	pdu->flags |= SNMP_MSG_AUTODISCOVER;
352 			return (SNMP_CODE_OK);
353 		}
354 
355 		if (pdu->engine.engine_boots != snmpd_engine.engine_boots ||
356 		    abs(pdu->engine.engine_time - snmpd_engine.engine_time) >
357 		    SNMP_TIME_WINDOW)
358 			return (SNMP_CODE_NOTINTIME);
359 	}
360 
361 	if (((pdu->flags & SNMP_MSG_PRIV_FLAG) != 0 &&
362 	    (pdu->flags & SNMP_MSG_AUTH_FLAG) == 0) ||
363 	    ((pdu->flags & SNMP_MSG_AUTH_FLAG) == 0 &&
364 	    usm_user->suser.auth_proto != SNMP_AUTH_NOAUTH) ||
365 	    ((pdu->flags & SNMP_MSG_PRIV_FLAG) == 0 &&
366 	    usm_user->suser.priv_proto != SNMP_PRIV_NOPRIV))
367 		return (SNMP_CODE_BADSECLEVEL);
368 
369 	return (SNMP_CODE_OK);
370 }
371 
372 /*
373  * Check whether access to each of var bindings in the PDU is allowed based
374  * on the user credentials against the configured User groups & VACM views.
375  */
376 enum snmp_code
377 snmp_pdu_auth_access(struct snmp_pdu *pdu, int32_t *ip)
378 {
379 	const char *uname;
380 	int32_t suboid, smodel;
381 	uint32_t i;
382 	struct vacm_user *vuser;
383 	struct vacm_access *acl;
384 	struct vacm_context *vacmctx;
385 	struct vacm_view *view;
386 
387 	/*
388 	 * At least a default context exists if the snmpd_vacm(3) module is
389 	 * running.
390 	 */
391 	if (SLIST_EMPTY(&vacm_contextlist) ||
392 	    (pdu->flags & SNMP_MSG_AUTODISCOVER) != 0)
393 		return (SNMP_CODE_OK);
394 
395 	switch (pdu->version) {
396 	case SNMP_V1:
397 		if ((uname = comm_string(community)) == NULL)
398 			return (SNMP_CODE_FAILED);
399 		smodel = SNMP_SECMODEL_SNMPv1;
400 		break;
401 
402 	case SNMP_V2c:
403 		if ((uname = comm_string(community)) == NULL)
404 			return (SNMP_CODE_FAILED);
405 		smodel = SNMP_SECMODEL_SNMPv2c;
406 		break;
407 
408 	case SNMP_V3:
409 		uname = pdu->user.sec_name;
410 		if ((smodel = pdu->security_model) !=  SNMP_SECMODEL_USM)
411 			return (SNMP_CODE_FAILED);
412 		/* Compare the PDU context engine id against the agent's */
413 		if (pdu->context_engine_len != snmpd_engine.engine_len ||
414 		    memcmp(pdu->context_engine, snmpd_engine.engine_id,
415 		    snmpd_engine.engine_len) != 0)
416 			return (SNMP_CODE_FAILED);
417 		break;
418 
419 	default:
420 		abort();
421 	}
422 
423 	SLIST_FOREACH(vuser, &vacm_userlist, vvu)
424 		if (strcmp(uname, vuser->secname) == 0 &&
425 		    vuser->sec_model == smodel)
426 			break;
427 
428 	if (vuser == NULL || vuser->group == NULL)
429 		return (SNMP_CODE_FAILED);
430 
431 	/* XXX: shteryana - recheck */
432 	TAILQ_FOREACH_REVERSE(acl, &vacm_accesslist, vacm_accesslist, vva) {
433 		if (acl->group != vuser->group)
434 			continue;
435 		SLIST_FOREACH(vacmctx, &vacm_contextlist, vcl)
436 			if (memcmp(vacmctx->ctxname, acl->ctx_prefix,
437 			    acl->ctx_match) == 0)
438 				goto match;
439 	}
440 
441 	return (SNMP_CODE_FAILED);
442 
443 match:
444 
445 	switch (pdu->type) {
446 	case SNMP_PDU_GET:
447 	case SNMP_PDU_GETNEXT:
448 	case SNMP_PDU_GETBULK:
449 		if ((view = acl->read_view) == NULL)
450 			return (SNMP_CODE_FAILED);
451 		break;
452 
453 	case SNMP_PDU_SET:
454 		if ((view = acl->write_view) == NULL)
455 			return (SNMP_CODE_FAILED);
456 		break;
457 
458 	case SNMP_PDU_TRAP:
459 	case SNMP_PDU_INFORM:
460 	case SNMP_PDU_TRAP2:
461 	case SNMP_PDU_REPORT:
462 		if ((view = acl->notify_view) == NULL)
463 			return (SNMP_CODE_FAILED);
464 		break;
465 	case SNMP_PDU_RESPONSE:
466 		/* NOTREACHED */
467 			return (SNMP_CODE_FAILED);
468 	default:
469 		abort();
470 	}
471 
472 	for (i = 0; i < pdu->nbindings; i++) {
473 		/* XXX - view->mask*/
474 		suboid = asn_is_suboid(&view->subtree, &pdu->bindings[i].var);
475 		if ((!suboid && !view->exclude) || (suboid && view->exclude)) {
476 			*ip = i + 1;
477 			return (SNMP_CODE_FAILED);
478 		}
479 	}
480 
481 	return (SNMP_CODE_OK);
482 }
483 
484 /*
485  * SNMP input. Start: decode the PDU, find the user or community.
486  */
487 enum snmpd_input_err
488 snmp_input_start(const u_char *buf, size_t len, const char *source,
489     struct snmp_pdu *pdu, int32_t *ip, size_t *pdulen)
490 {
491 	struct asn_buf b;
492 	enum snmp_code code;
493 	enum snmpd_input_err ret;
494 	int sret;
495 
496 	/* update uptime */
497 	this_tick = get_ticks();
498 
499 	b.asn_cptr = buf;
500 	b.asn_len = len;
501 
502 	/* look whether we have enough bytes for the entire PDU. */
503 	switch (sret = snmp_pdu_snoop(&b)) {
504 
505 	  case 0:
506 		return (SNMPD_INPUT_TRUNC);
507 
508 	  case -1:
509 		snmpd_stats.inASNParseErrs++;
510 		return (SNMPD_INPUT_FAILED);
511 	}
512 	b.asn_len = *pdulen = (size_t)sret;
513 
514 	memset(pdu, 0, sizeof(*pdu));
515 	if ((code = snmp_pdu_decode_header(&b, pdu)) != SNMP_CODE_OK)
516 		goto decoded;
517 
518 	if (pdu->version == SNMP_V3) {
519 		if (pdu->security_model != SNMP_SECMODEL_USM) {
520 			code = SNMP_CODE_FAILED;
521 			goto decoded;
522 		}
523 		if ((code = snmp_pdu_auth_user(pdu)) != SNMP_CODE_OK)
524 		    	goto decoded;
525 		if ((code =  snmp_pdu_decode_secmode(&b, pdu)) != SNMP_CODE_OK)
526 			goto decoded;
527 	}
528 	code = snmp_pdu_decode_scoped(&b, pdu, ip);
529 
530 	ret = SNMPD_INPUT_OK;
531 
532 decoded:
533 	snmpd_stats.inPkts++;
534 
535 	switch (code) {
536 
537 	  case SNMP_CODE_FAILED:
538 		snmpd_stats.inASNParseErrs++;
539 		return (SNMPD_INPUT_FAILED);
540 
541 	  case SNMP_CODE_BADVERS:
542 	  bad_vers:
543 		snmpd_stats.inBadVersions++;
544 		return (SNMPD_INPUT_FAILED);
545 
546 	  case SNMP_CODE_BADLEN:
547 		if (pdu->type == SNMP_OP_SET)
548 			ret = SNMPD_INPUT_VALBADLEN;
549 		break;
550 
551 	  case SNMP_CODE_OORANGE:
552 		if (pdu->type == SNMP_OP_SET)
553 			ret = SNMPD_INPUT_VALRANGE;
554 		break;
555 
556 	  case SNMP_CODE_BADENC:
557 		if (pdu->type == SNMP_OP_SET)
558 			ret = SNMPD_INPUT_VALBADENC;
559 		break;
560 
561 	  case SNMP_CODE_BADSECLEVEL:
562 		snmpd_usmstats.unsupported_seclevels++;
563 		return (SNMPD_INPUT_FAILED);
564 
565 	  case SNMP_CODE_NOTINTIME:
566 		snmpd_usmstats.not_in_time_windows++;
567 		return (SNMPD_INPUT_FAILED);
568 
569 	  case SNMP_CODE_BADUSER:
570 		snmpd_usmstats.unknown_users++;
571 		return (SNMPD_INPUT_FAILED);
572 
573 	  case SNMP_CODE_BADENGINE:
574 		snmpd_usmstats.unknown_engine_ids++;
575 		return (SNMPD_INPUT_FAILED);
576 
577 	  case SNMP_CODE_BADDIGEST:
578 		snmpd_usmstats.wrong_digests++;
579 		return (SNMPD_INPUT_FAILED);
580 
581 	  case SNMP_CODE_EDECRYPT:
582 		snmpd_usmstats.decrypt_errors++;
583 		return (SNMPD_INPUT_FAILED);
584 
585 	  case SNMP_CODE_OK:
586 		switch (pdu->version) {
587 
588 		  case SNMP_V1:
589 			if (!(snmpd.version_enable & VERS_ENABLE_V1))
590 				goto bad_vers;
591 			break;
592 
593 		  case SNMP_V2c:
594 			if (!(snmpd.version_enable & VERS_ENABLE_V2C))
595 				goto bad_vers;
596 			break;
597 
598 		  case SNMP_V3:
599 		  	if (!(snmpd.version_enable & VERS_ENABLE_V3))
600 				goto bad_vers;
601 			break;
602 
603 		  case SNMP_Verr:
604 			goto bad_vers;
605 		}
606 		break;
607 	}
608 
609 	if (debug.dump_pdus) {
610 		snmp_printf("%s -> ", source);
611 		snmp_pdu_dump(pdu);
612 	}
613 
614 	/*
615 	 * Look, whether we know the community or user
616 	 */
617 
618 	if (pdu->version != SNMP_V3) {
619 		TAILQ_FOREACH(comm, &community_list, link)
620 			if (comm->string != NULL &&
621 			    strcmp(comm->string, pdu->community) == 0)
622 				break;
623 
624 		if (comm == NULL) {
625 			snmpd_stats.inBadCommunityNames++;
626 			snmp_pdu_free(pdu);
627 			if (snmpd.auth_traps)
628 				snmp_send_trap(&oid_authenticationFailure,
629 				    (struct snmp_value *)NULL);
630 			ret = SNMPD_INPUT_BAD_COMM;
631 		} else
632 			community = comm->value;
633 	} else if (pdu->nbindings == 0) {
634 		/* RFC 3414 - snmpEngineID Discovery */
635 		if (strlen(pdu->user.sec_name) == 0) {
636 			asn_append_oid(&(pdu->bindings[pdu->nbindings++].var),
637 			    &oid_usmUnknownEngineIDs);
638 			pdu->context_engine_len = snmpd_engine.engine_len;
639 			memcpy(pdu->context_engine, snmpd_engine.engine_id,
640 			    snmpd_engine.engine_len);
641 		} else if (pdu->engine.engine_boots == 0 &&
642 		    pdu->engine.engine_time == 0) {
643 			asn_append_oid(&(pdu->bindings[pdu->nbindings++].var),
644 			    &oid_usmNotInTimeWindows);
645 			pdu->engine.engine_boots = snmpd_engine.engine_boots;
646 			pdu->engine.engine_time = snmpd_engine.engine_time;
647 		}
648 	} else if (usm_user->suser.auth_proto != SNMP_AUTH_NOAUTH &&
649 	     (pdu->engine.engine_boots == 0 || pdu->engine.engine_time == 0)) {
650 		snmpd_usmstats.not_in_time_windows++;
651 		ret = SNMPD_INPUT_FAILED;
652 	}
653 
654 	if ((code = snmp_pdu_auth_access(pdu, ip)) != SNMP_CODE_OK)
655 		ret = SNMPD_INPUT_FAILED;
656 
657 	return (ret);
658 }
659 
660 /*
661  * Will return only _OK or _FAILED
662  */
663 enum snmpd_input_err
664 snmp_input_finish(struct snmp_pdu *pdu, const u_char *rcvbuf, size_t rcvlen,
665     u_char *sndbuf, size_t *sndlen, const char *source,
666     enum snmpd_input_err ierr, int32_t ivar, void *data)
667 {
668 	struct snmp_pdu resp;
669 	struct asn_buf resp_b, pdu_b;
670 	enum snmp_ret ret;
671 
672 	resp_b.asn_ptr = sndbuf;
673 	resp_b.asn_len = snmpd.txbuf;
674 
675 	pdu_b.asn_cptr = rcvbuf;
676 	pdu_b.asn_len = rcvlen;
677 
678 	if (ierr != SNMPD_INPUT_OK) {
679 		/* error decoding the input of a SET */
680 		if (pdu->version == SNMP_V1)
681 			pdu->error_status = SNMP_ERR_BADVALUE;
682 		else if (ierr == SNMPD_INPUT_VALBADLEN)
683 			pdu->error_status = SNMP_ERR_WRONG_LENGTH;
684 		else if (ierr == SNMPD_INPUT_VALRANGE)
685 			pdu->error_status = SNMP_ERR_WRONG_VALUE;
686 		else
687 			pdu->error_status = SNMP_ERR_WRONG_ENCODING;
688 
689 		pdu->error_index = ivar;
690 
691 		if (snmp_make_errresp(pdu, &pdu_b, &resp_b) == SNMP_RET_IGN) {
692 			syslog(LOG_WARNING, "could not encode error response");
693 			snmpd_stats.silentDrops++;
694 			return (SNMPD_INPUT_FAILED);
695 		}
696 
697 		if (debug.dump_pdus) {
698 			snmp_printf("%s <- ", source);
699 			snmp_pdu_dump(pdu);
700 		}
701 		*sndlen = (size_t)(resp_b.asn_ptr - sndbuf);
702 		return (SNMPD_INPUT_OK);
703 	}
704 
705 	switch (pdu->type) {
706 
707 	  case SNMP_PDU_GET:
708 		ret = snmp_get(pdu, &resp_b, &resp, data);
709 		break;
710 
711 	  case SNMP_PDU_GETNEXT:
712 		ret = snmp_getnext(pdu, &resp_b, &resp, data);
713 		break;
714 
715 	  case SNMP_PDU_SET:
716 		ret = snmp_set(pdu, &resp_b, &resp, data);
717 		break;
718 
719 	  case SNMP_PDU_GETBULK:
720 		ret = snmp_getbulk(pdu, &resp_b, &resp, data);
721 		break;
722 
723 	  default:
724 		ret = SNMP_RET_IGN;
725 		break;
726 	}
727 
728 	switch (ret) {
729 
730 	  case SNMP_RET_OK:
731 		/* normal return - send a response */
732 		if (debug.dump_pdus) {
733 			snmp_printf("%s <- ", source);
734 			snmp_pdu_dump(&resp);
735 		}
736 		*sndlen = (size_t)(resp_b.asn_ptr - sndbuf);
737 		snmp_pdu_free(&resp);
738 		return (SNMPD_INPUT_OK);
739 
740 	  case SNMP_RET_IGN:
741 		/* error - send nothing */
742 		snmpd_stats.silentDrops++;
743 		return (SNMPD_INPUT_FAILED);
744 
745 	  case SNMP_RET_ERR:
746 		/* error - send error response. The snmp routine has
747 		 * changed the error fields in the original message. */
748 		resp_b.asn_ptr = sndbuf;
749 		resp_b.asn_len = snmpd.txbuf;
750 		if (snmp_make_errresp(pdu, &pdu_b, &resp_b) == SNMP_RET_IGN) {
751 			syslog(LOG_WARNING, "could not encode error response");
752 			snmpd_stats.silentDrops++;
753 			return (SNMPD_INPUT_FAILED);
754 		} else {
755 			if (debug.dump_pdus) {
756 				snmp_printf("%s <- ", source);
757 				snmp_pdu_dump(pdu);
758 			}
759 			*sndlen = (size_t)(resp_b.asn_ptr - sndbuf);
760 			return (SNMPD_INPUT_OK);
761 		}
762 	}
763 	abort();
764 }
765 
766 /*
767  * Insert a port into the right place in the transport's table of ports
768  */
769 void
770 trans_insert_port(struct transport *t, struct tport *port)
771 {
772 	struct tport *p;
773 
774 	TAILQ_FOREACH(p, &t->table, link) {
775 		if (asn_compare_oid(&p->index, &port->index) > 0) {
776 			TAILQ_INSERT_BEFORE(p, port, link);
777 			return;
778 		}
779 	}
780 	port->transport = t;
781 	TAILQ_INSERT_TAIL(&t->table, port, link);
782 }
783 
784 /*
785  * Remove a port from a transport's list
786  */
787 void
788 trans_remove_port(struct tport *port)
789 {
790 
791 	TAILQ_REMOVE(&port->transport->table, port, link);
792 }
793 
794 /*
795  * Find a port on a transport's list
796  */
797 struct tport *
798 trans_find_port(struct transport *t, const struct asn_oid *idx, u_int sub)
799 {
800 
801 	return (FIND_OBJECT_OID(&t->table, idx, sub));
802 }
803 
804 /*
805  * Find next port on a transport's list
806  */
807 struct tport *
808 trans_next_port(struct transport *t, const struct asn_oid *idx, u_int sub)
809 {
810 
811 	return (NEXT_OBJECT_OID(&t->table, idx, sub));
812 }
813 
814 /*
815  * Return first port
816  */
817 struct tport *
818 trans_first_port(struct transport *t)
819 {
820 
821 	return (TAILQ_FIRST(&t->table));
822 }
823 
824 /*
825  * Iterate through all ports until a function returns a 0.
826  */
827 struct tport *
828 trans_iter_port(struct transport *t, int (*func)(struct tport *, intptr_t),
829     intptr_t arg)
830 {
831 	struct tport *p;
832 
833 	TAILQ_FOREACH(p, &t->table, link)
834 		if (func(p, arg) == 0)
835 			return (p);
836 	return (NULL);
837 }
838 
839 /*
840  * Register a transport
841  */
842 int
843 trans_register(const struct transport_def *def, struct transport **pp)
844 {
845 	u_int i;
846 	char or_descr[256];
847 
848 	if ((*pp = malloc(sizeof(**pp))) == NULL)
849 		return (SNMP_ERR_GENERR);
850 
851 	/* construct index */
852 	(*pp)->index.len = strlen(def->name) + 1;
853 	(*pp)->index.subs[0] = strlen(def->name);
854 	for (i = 0; i < (*pp)->index.subs[0]; i++)
855 		(*pp)->index.subs[i + 1] = def->name[i];
856 
857 	(*pp)->vtab = def;
858 
859 	if (FIND_OBJECT_OID(&transport_list, &(*pp)->index, 0) != NULL) {
860 		free(*pp);
861 		return (SNMP_ERR_INCONS_VALUE);
862 	}
863 
864 	/* register module */
865 	snprintf(or_descr, sizeof(or_descr), "%s transport mapping", def->name);
866 	if (((*pp)->or_index = or_register(&def->id, or_descr, NULL)) == 0) {
867 		free(*pp);
868 		return (SNMP_ERR_GENERR);
869 	}
870 
871 	INSERT_OBJECT_OID((*pp), &transport_list);
872 
873 	TAILQ_INIT(&(*pp)->table);
874 
875 	return (SNMP_ERR_NOERROR);
876 }
877 
878 /*
879  * Unregister transport
880  */
881 int
882 trans_unregister(struct transport *t)
883 {
884 	if (!TAILQ_EMPTY(&t->table))
885 		return (SNMP_ERR_INCONS_VALUE);
886 
887 	or_unregister(t->or_index);
888 	TAILQ_REMOVE(&transport_list, t, link);
889 
890 	return (SNMP_ERR_NOERROR);
891 }
892 
893 /*
894  * File descriptor support
895  */
896 #ifdef USE_LIBBEGEMOT
897 static void
898 input(int fd, int mask __unused, void *uap)
899 #else
900 static void
901 input(evContext ctx __unused, void *uap, int fd, int mask __unused)
902 #endif
903 {
904 	struct fdesc *f = uap;
905 
906 	(*f->func)(fd, f->udata);
907 }
908 
909 void
910 fd_suspend(void *p)
911 {
912 	struct fdesc *f = p;
913 
914 #ifdef USE_LIBBEGEMOT
915 	if (f->id >= 0) {
916 		poll_unregister(f->id);
917 		f->id = -1;
918 	}
919 #else
920 	if (evTestID(f->id)) {
921 		(void)evDeselectFD(evctx, f->id);
922 		evInitID(&f->id);
923 	}
924 #endif
925 }
926 
927 int
928 fd_resume(void *p)
929 {
930 	struct fdesc *f = p;
931 	int err;
932 
933 #ifdef USE_LIBBEGEMOT
934 	if (f->id >= 0)
935 		return (0);
936 	if ((f->id = poll_register(f->fd, input, f, POLL_IN)) < 0) {
937 		err = errno;
938 		syslog(LOG_ERR, "select fd %d: %m", f->fd);
939 		errno = err;
940 		return (-1);
941 	}
942 #else
943 	if (evTestID(f->id))
944 		return (0);
945 	if (evSelectFD(evctx, f->fd, EV_READ, input, f, &f->id)) {
946 		err = errno;
947 		syslog(LOG_ERR, "select fd %d: %m", f->fd);
948 		errno = err;
949 		return (-1);
950 	}
951 #endif
952 	return (0);
953 }
954 
955 void *
956 fd_select(int fd, void (*func)(int, void *), void *udata, struct lmodule *mod)
957 {
958 	struct fdesc *f;
959 	int err;
960 
961 	if ((f = malloc(sizeof(struct fdesc))) == NULL) {
962 		err = errno;
963 		syslog(LOG_ERR, "fd_select: %m");
964 		errno = err;
965 		return (NULL);
966 	}
967 	f->fd = fd;
968 	f->func = func;
969 	f->udata = udata;
970 	f->owner = mod;
971 #ifdef USE_LIBBEGEMOT
972 	f->id = -1;
973 #else
974 	evInitID(&f->id);
975 #endif
976 
977 	if (fd_resume(f)) {
978 		err = errno;
979 		free(f);
980 		errno = err;
981 		return (NULL);
982 	}
983 
984 	LIST_INSERT_HEAD(&fdesc_list, f, link);
985 
986 	return (f);
987 }
988 
989 void
990 fd_deselect(void *p)
991 {
992 	struct fdesc *f = p;
993 
994 	LIST_REMOVE(f, link);
995 	fd_suspend(f);
996 	free(f);
997 }
998 
999 static void
1000 fd_flush(struct lmodule *mod)
1001 {
1002 	struct fdesc *t, *t1;
1003 
1004 	t = LIST_FIRST(&fdesc_list);
1005 	while (t != NULL) {
1006 		t1 = LIST_NEXT(t, link);
1007 		if (t->owner == mod)
1008 			fd_deselect(t);
1009 		t = t1;
1010 	}
1011 }
1012 
1013 /*
1014  * Consume a message from the input buffer
1015  */
1016 static void
1017 snmp_input_consume(struct port_input *pi)
1018 {
1019 	if (!pi->stream) {
1020 		/* always consume everything */
1021 		pi->length = 0;
1022 		return;
1023 	}
1024 	if (pi->consumed >= pi->length) {
1025 		/* all bytes consumed */
1026 		pi->length = 0;
1027 		return;
1028 	}
1029 	memmove(pi->buf, pi->buf + pi->consumed, pi->length - pi->consumed);
1030 	pi->length -= pi->consumed;
1031 }
1032 
1033 static void
1034 check_priv_dgram(struct port_input *pi, struct sockcred *cred)
1035 {
1036 
1037 	/* process explicitly sends credentials */
1038 	if (cred)
1039 		pi->priv = (cred->sc_euid == 0);
1040 	else
1041 		pi->priv = 0;
1042 }
1043 
1044 static void
1045 check_priv_stream(struct port_input *pi)
1046 {
1047 	struct xucred ucred;
1048 	socklen_t ucredlen;
1049 
1050 	/* obtain the accept time credentials */
1051 	ucredlen = sizeof(ucred);
1052 
1053 	if (getsockopt(pi->fd, 0, LOCAL_PEERCRED, &ucred, &ucredlen) == 0 &&
1054 	    ucredlen >= sizeof(ucred) && ucred.cr_version == XUCRED_VERSION)
1055 		pi->priv = (ucred.cr_uid == 0);
1056 	else
1057 		pi->priv = 0;
1058 }
1059 
1060 /*
1061  * Input from a stream socket.
1062  */
1063 static int
1064 recv_stream(struct port_input *pi)
1065 {
1066 	struct msghdr msg;
1067 	struct iovec iov[1];
1068 	ssize_t len;
1069 
1070 	if (pi->buf == NULL) {
1071 		/* no buffer yet - allocate one */
1072 		if ((pi->buf = buf_alloc(0)) == NULL) {
1073 			/* ups - could not get buffer. Return an error
1074 			 * the caller must close the transport. */
1075 			return (-1);
1076 		}
1077 		pi->buflen = buf_size(0);
1078 		pi->consumed = 0;
1079 		pi->length = 0;
1080 	}
1081 
1082 	/* try to get a message */
1083 	msg.msg_name = pi->peer;
1084 	msg.msg_namelen = pi->peerlen;
1085 	msg.msg_iov = iov;
1086 	msg.msg_iovlen = 1;
1087 	msg.msg_control = NULL;
1088 	msg.msg_controllen = 0;
1089 	msg.msg_flags = 0;
1090 
1091 	iov[0].iov_base = pi->buf + pi->length;
1092 	iov[0].iov_len = pi->buflen - pi->length;
1093 
1094 	len = recvmsg(pi->fd, &msg, 0);
1095 
1096 	if (len == -1 || len == 0)
1097 		/* receive error */
1098 		return (-1);
1099 
1100 	pi->length += len;
1101 
1102 	if (pi->cred)
1103 		check_priv_stream(pi);
1104 
1105 	return (0);
1106 }
1107 
1108 /*
1109  * Input from a datagram socket.
1110  * Each receive should return one datagram.
1111  */
1112 static int
1113 recv_dgram(struct port_input *pi, struct in_addr *laddr)
1114 {
1115 	u_char embuf[1000];
1116 	char cbuf[CMSG_SPACE(SOCKCREDSIZE(CMGROUP_MAX)) +
1117 	    CMSG_SPACE(sizeof(struct in_addr))];
1118 	struct msghdr msg;
1119 	struct iovec iov[1];
1120 	ssize_t len;
1121 	struct cmsghdr *cmsg;
1122 	struct sockcred *cred = NULL;
1123 
1124 	if (pi->buf == NULL) {
1125 		/* no buffer yet - allocate one */
1126 		if ((pi->buf = buf_alloc(0)) == NULL) {
1127 			/* ups - could not get buffer. Read away input
1128 			 * and drop it */
1129 			(void)recvfrom(pi->fd, embuf, sizeof(embuf),
1130 			    0, NULL, NULL);
1131 			/* return error */
1132 			return (-1);
1133 		}
1134 		pi->buflen = buf_size(0);
1135 	}
1136 
1137 	/* try to get a message */
1138 	msg.msg_name = pi->peer;
1139 	msg.msg_namelen = pi->peerlen;
1140 	msg.msg_iov = iov;
1141 	msg.msg_iovlen = 1;
1142 	memset(cbuf, 0, sizeof(cbuf));
1143 	msg.msg_control = cbuf;
1144 	msg.msg_controllen = sizeof(cbuf);
1145 	msg.msg_flags = 0;
1146 
1147 	iov[0].iov_base = pi->buf;
1148 	iov[0].iov_len = pi->buflen;
1149 
1150 	len = recvmsg(pi->fd, &msg, 0);
1151 
1152 	if (len == -1 || len == 0)
1153 		/* receive error */
1154 		return (-1);
1155 
1156 	if (msg.msg_flags & MSG_TRUNC) {
1157 		/* truncated - drop */
1158 		snmpd_stats.silentDrops++;
1159 		snmpd_stats.inTooLong++;
1160 		return (-1);
1161 	}
1162 
1163 	pi->length = (size_t)len;
1164 
1165 	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
1166 	    cmsg = CMSG_NXTHDR(&msg, cmsg)) {
1167 		if (cmsg->cmsg_level == IPPROTO_IP &&
1168 		    cmsg->cmsg_type == IP_RECVDSTADDR)
1169 			memcpy(laddr, CMSG_DATA(cmsg), sizeof(struct in_addr));
1170 		if (cmsg->cmsg_level == SOL_SOCKET &&
1171 		    cmsg->cmsg_type == SCM_CREDS)
1172 			memcpy(cred, CMSG_DATA(cmsg), sizeof(struct sockcred));
1173 	}
1174 
1175 	if (pi->cred)
1176 		check_priv_dgram(pi, cred);
1177 
1178 	return (0);
1179 }
1180 
1181 /*
1182  * Input from a socket
1183  */
1184 int
1185 snmpd_input(struct port_input *pi, struct tport *tport)
1186 {
1187 	u_char *sndbuf;
1188 	size_t sndlen;
1189 	struct snmp_pdu pdu;
1190 	enum snmpd_input_err ierr, ferr;
1191 	enum snmpd_proxy_err perr;
1192 	int32_t vi;
1193 	int ret;
1194 	ssize_t slen;
1195 #ifdef USE_TCPWRAPPERS
1196 	char client[16];
1197 #endif
1198 	struct msghdr msg;
1199 	struct iovec iov[1];
1200 	char cbuf[CMSG_SPACE(sizeof(struct in_addr))];
1201 	struct cmsghdr *cmsgp;
1202 
1203 	/* get input depending on the transport */
1204 	if (pi->stream) {
1205 		msg.msg_control = NULL;
1206 		msg.msg_controllen = 0;
1207 
1208 		ret = recv_stream(pi);
1209 	} else {
1210 		struct in_addr laddr;
1211 
1212 		memset(cbuf, 0, CMSG_SPACE(sizeof(struct in_addr)));
1213 		msg.msg_control = cbuf;
1214 		msg.msg_controllen = CMSG_SPACE(sizeof(struct in_addr));
1215 		cmsgp = CMSG_FIRSTHDR(&msg);
1216 		cmsgp->cmsg_len = CMSG_LEN(sizeof(struct in_addr));
1217 		cmsgp->cmsg_level = IPPROTO_IP;
1218 		cmsgp->cmsg_type = IP_SENDSRCADDR;
1219 		memcpy(&laddr, CMSG_DATA(cmsgp), sizeof(struct in_addr));
1220 
1221 		ret = recv_dgram(pi, &laddr);
1222 
1223 		if (laddr.s_addr == 0) {
1224 			msg.msg_control = NULL;
1225 			msg.msg_controllen = 0;
1226 		}
1227 	}
1228 
1229 	if (ret == -1)
1230 		return (-1);
1231 
1232 #ifdef USE_TCPWRAPPERS
1233 	/*
1234 	 * In case of AF_INET{6} peer, do hosts_access(5) check.
1235 	 */
1236 	if (pi->peer->sa_family != AF_LOCAL &&
1237 	    inet_ntop(pi->peer->sa_family,
1238 	    &((const struct sockaddr_in *)(const void *)pi->peer)->sin_addr,
1239 	    client, sizeof(client)) != NULL) {
1240 		request_set(&req, RQ_CLIENT_ADDR, client, 0);
1241 		if (hosts_access(&req) == 0) {
1242 			syslog(LOG_ERR, "refused connection from %.500s",
1243 			    eval_client(&req));
1244 			return (-1);
1245 		}
1246 	} else if (pi->peer->sa_family != AF_LOCAL)
1247 		syslog(LOG_ERR, "inet_ntop(): %m");
1248 #endif
1249 
1250 	/*
1251 	 * Handle input
1252 	 */
1253 	ierr = snmp_input_start(pi->buf, pi->length, "SNMP", &pdu, &vi,
1254 	    &pi->consumed);
1255 	if (ierr == SNMPD_INPUT_TRUNC) {
1256 		/* need more bytes. This is ok only for streaming transports.
1257 		 * but only if we have not reached bufsiz yet. */
1258 		if (pi->stream) {
1259 			if (pi->length == buf_size(0)) {
1260 				snmpd_stats.silentDrops++;
1261 				return (-1);
1262 			}
1263 			return (0);
1264 		}
1265 		snmpd_stats.silentDrops++;
1266 		return (-1);
1267 	}
1268 
1269 	/* can't check for bad SET pdus here, because a proxy may have to
1270 	 * check the access first. We don't want to return an error response
1271 	 * to a proxy PDU with a wrong community */
1272 	if (ierr == SNMPD_INPUT_FAILED) {
1273 		/* for streaming transports this is fatal */
1274 		if (pi->stream)
1275 			return (-1);
1276 		snmp_input_consume(pi);
1277 		return (0);
1278 	}
1279 	if (ierr == SNMPD_INPUT_BAD_COMM) {
1280 		snmp_input_consume(pi);
1281 		return (0);
1282 	}
1283 
1284 	/*
1285 	 * If that is a module community and the module has a proxy function,
1286 	 * the hand it over to the module.
1287 	 */
1288 	if (comm != NULL && comm->owner != NULL &&
1289 	    comm->owner->config->proxy != NULL) {
1290 		perr = (*comm->owner->config->proxy)(&pdu, tport->transport,
1291 		    &tport->index, pi->peer, pi->peerlen, ierr, vi,
1292 		    !pi->cred || pi->priv);
1293 
1294 		switch (perr) {
1295 
1296 		  case SNMPD_PROXY_OK:
1297 			snmp_input_consume(pi);
1298 			return (0);
1299 
1300 		  case SNMPD_PROXY_REJ:
1301 			break;
1302 
1303 		  case SNMPD_PROXY_DROP:
1304 			snmp_input_consume(pi);
1305 			snmp_pdu_free(&pdu);
1306 			snmpd_stats.proxyDrops++;
1307 			return (0);
1308 
1309 		  case SNMPD_PROXY_BADCOMM:
1310 			snmp_input_consume(pi);
1311 			snmp_pdu_free(&pdu);
1312 			snmpd_stats.inBadCommunityNames++;
1313 			if (snmpd.auth_traps)
1314 				snmp_send_trap(&oid_authenticationFailure,
1315 				    (struct snmp_value *)NULL);
1316 			return (0);
1317 
1318 		  case SNMPD_PROXY_BADCOMMUSE:
1319 			snmp_input_consume(pi);
1320 			snmp_pdu_free(&pdu);
1321 			snmpd_stats.inBadCommunityUses++;
1322 			if (snmpd.auth_traps)
1323 				snmp_send_trap(&oid_authenticationFailure,
1324 				    (struct snmp_value *)NULL);
1325 			return (0);
1326 		}
1327 	}
1328 
1329 	/*
1330 	 * Check type
1331 	 */
1332 	if (pdu.type == SNMP_PDU_RESPONSE ||
1333 	    pdu.type == SNMP_PDU_TRAP ||
1334 	    pdu.type == SNMP_PDU_TRAP2) {
1335 		snmpd_stats.silentDrops++;
1336 		snmpd_stats.inBadPduTypes++;
1337 		snmp_pdu_free(&pdu);
1338 		snmp_input_consume(pi);
1339 		return (0);
1340 	}
1341 
1342 	/*
1343 	 * Check community
1344 	 */
1345 	if (pdu.version < SNMP_V3 &&
1346 	    ((pi->cred && !pi->priv && pdu.type == SNMP_PDU_SET) ||
1347 	    (community != COMM_WRITE &&
1348             (pdu.type == SNMP_PDU_SET || community != COMM_READ)))) {
1349 		snmpd_stats.inBadCommunityUses++;
1350 		snmp_pdu_free(&pdu);
1351 		snmp_input_consume(pi);
1352 		if (snmpd.auth_traps)
1353 			snmp_send_trap(&oid_authenticationFailure,
1354 			    (struct snmp_value *)NULL);
1355 		return (0);
1356 	}
1357 
1358 	/*
1359 	 * Execute it.
1360 	 */
1361 	if ((sndbuf = buf_alloc(1)) == NULL) {
1362 		snmpd_stats.silentDrops++;
1363 		snmp_pdu_free(&pdu);
1364 		snmp_input_consume(pi);
1365 		return (0);
1366 	}
1367 	ferr = snmp_input_finish(&pdu, pi->buf, pi->length,
1368 	    sndbuf, &sndlen, "SNMP", ierr, vi, NULL);
1369 
1370 	if (ferr == SNMPD_INPUT_OK) {
1371 		msg.msg_name = pi->peer;
1372 		msg.msg_namelen = pi->peerlen;
1373 		msg.msg_iov = iov;
1374 		msg.msg_iovlen = 1;
1375 		msg.msg_flags = 0;
1376 		iov[0].iov_base = sndbuf;
1377 		iov[0].iov_len = sndlen;
1378 
1379 		slen = sendmsg(pi->fd, &msg, 0);
1380 		if (slen == -1)
1381 			syslog(LOG_ERR, "sendmsg: %m");
1382 		else if ((size_t)slen != sndlen)
1383 			syslog(LOG_ERR, "sendmsg: short write %zu/%zu",
1384 			    sndlen, (size_t)slen);
1385 	}
1386 	snmp_pdu_free(&pdu);
1387 	free(sndbuf);
1388 	snmp_input_consume(pi);
1389 
1390 	return (0);
1391 }
1392 
1393 /*
1394  * Send a PDU to a given port
1395  */
1396 void
1397 snmp_send_port(void *targ, const struct asn_oid *port, struct snmp_pdu *pdu,
1398     const struct sockaddr *addr, socklen_t addrlen)
1399 {
1400 	struct transport *trans = targ;
1401 	struct tport *tp;
1402 	u_char *sndbuf;
1403 	size_t sndlen;
1404 	ssize_t len;
1405 
1406 	TAILQ_FOREACH(tp, &trans->table, link)
1407 		if (asn_compare_oid(port, &tp->index) == 0)
1408 			break;
1409 	if (tp == 0)
1410 		return;
1411 
1412 	if ((sndbuf = buf_alloc(1)) == NULL)
1413 		return;
1414 
1415 	snmp_output(pdu, sndbuf, &sndlen, "SNMP PROXY");
1416 
1417 	len = trans->vtab->send(tp, sndbuf, sndlen, addr, addrlen);
1418 
1419 	if (len == -1)
1420 		syslog(LOG_ERR, "sendto: %m");
1421 	else if ((size_t)len != sndlen)
1422 		syslog(LOG_ERR, "sendto: short write %zu/%zu",
1423 		    sndlen, (size_t)len);
1424 
1425 	free(sndbuf);
1426 }
1427 
1428 
1429 /*
1430  * Close an input source
1431  */
1432 void
1433 snmpd_input_close(struct port_input *pi)
1434 {
1435 	if (pi->id != NULL)
1436 		fd_deselect(pi->id);
1437 	if (pi->fd >= 0)
1438 		(void)close(pi->fd);
1439 	if (pi->buf != NULL)
1440 		free(pi->buf);
1441 }
1442 
1443 /*
1444  * Dump internal state.
1445  */
1446 #ifdef USE_LIBBEGEMOT
1447 static void
1448 info_func(void)
1449 #else
1450 static void
1451 info_func(evContext ctx __unused, void *uap __unused, const void *tag __unused)
1452 #endif
1453 {
1454 	struct lmodule *m;
1455 	u_int i;
1456 	char buf[10000];
1457 
1458 	syslog(LOG_DEBUG, "Dump of SNMPd %lu\n", (u_long)getpid());
1459 	for (i = 0; i < tree_size; i++) {
1460 		switch (tree[i].type) {
1461 
1462 		  case SNMP_NODE_LEAF:
1463 			sprintf(buf, "LEAF: %s %s", tree[i].name,
1464 			    asn_oid2str(&tree[i].oid));
1465 			break;
1466 
1467 		  case SNMP_NODE_COLUMN:
1468 			sprintf(buf, "COL: %s %s", tree[i].name,
1469 			    asn_oid2str(&tree[i].oid));
1470 			break;
1471 		}
1472 		syslog(LOG_DEBUG, "%s", buf);
1473 	}
1474 
1475 	TAILQ_FOREACH(m, &lmodules, link)
1476 		if (m->config->dump)
1477 			(*m->config->dump)();
1478 }
1479 
1480 /*
1481  * Re-read configuration
1482  */
1483 #ifdef USE_LIBBEGEMOT
1484 static void
1485 config_func(void)
1486 #else
1487 static void
1488 config_func(evContext ctx __unused, void *uap __unused,
1489     const void *tag __unused)
1490 #endif
1491 {
1492 	struct lmodule *m;
1493 
1494 	if (read_config(config_file, NULL)) {
1495 		syslog(LOG_ERR, "error reading config file '%s'", config_file);
1496 		return;
1497 	}
1498 	TAILQ_FOREACH(m, &lmodules, link)
1499 		if (m->config->config)
1500 			(*m->config->config)();
1501 }
1502 
1503 /*
1504  * On USR1 dump actual configuration.
1505  */
1506 static void
1507 onusr1(int s __unused)
1508 {
1509 
1510 	work |= WORK_DOINFO;
1511 }
1512 static void
1513 onhup(int s __unused)
1514 {
1515 
1516 	work |= WORK_RECONFIG;
1517 }
1518 
1519 static void
1520 onterm(int s __unused)
1521 {
1522 
1523 	/* allow clean-up */
1524 	exit(0);
1525 }
1526 
1527 static void
1528 init_sigs(void)
1529 {
1530 	struct sigaction sa;
1531 
1532 	sa.sa_handler = onusr1;
1533 	sa.sa_flags = SA_RESTART;
1534 	sigemptyset(&sa.sa_mask);
1535 	if (sigaction(SIGUSR1, &sa, NULL)) {
1536 		syslog(LOG_ERR, "sigaction: %m");
1537 		exit(1);
1538 	}
1539 
1540 	sa.sa_handler = onhup;
1541 	if (sigaction(SIGHUP, &sa, NULL)) {
1542 		syslog(LOG_ERR, "sigaction: %m");
1543 		exit(1);
1544 	}
1545 
1546 	sa.sa_handler = onterm;
1547 	sa.sa_flags = 0;
1548 	sigemptyset(&sa.sa_mask);
1549 	if (sigaction(SIGTERM, &sa, NULL)) {
1550 		syslog(LOG_ERR, "sigaction: %m");
1551 		exit(1);
1552 	}
1553 	if (sigaction(SIGINT, &sa, NULL)) {
1554 		syslog(LOG_ERR, "sigaction: %m");
1555 		exit(1);
1556 	}
1557 }
1558 
1559 static void
1560 block_sigs(void)
1561 {
1562 	sigset_t set;
1563 
1564 	sigfillset(&set);
1565 	if (sigprocmask(SIG_BLOCK, &set, &blocked_sigs) == -1) {
1566 		syslog(LOG_ERR, "SIG_BLOCK: %m");
1567 		exit(1);
1568 	}
1569 }
1570 static void
1571 unblock_sigs(void)
1572 {
1573 	if (sigprocmask(SIG_SETMASK, &blocked_sigs, NULL) == -1) {
1574 		syslog(LOG_ERR, "SIG_SETMASK: %m");
1575 		exit(1);
1576 	}
1577 }
1578 
1579 /*
1580  * Shut down
1581  */
1582 static void
1583 term(void)
1584 {
1585 	(void)unlink(pid_file);
1586 }
1587 
1588 static void
1589 trans_stop(void)
1590 {
1591 	struct transport *t;
1592 
1593 	TAILQ_FOREACH(t, &transport_list, link)
1594 		(void)t->vtab->stop(1);
1595 }
1596 
1597 /*
1598  * Define a macro from the command line
1599  */
1600 static void
1601 do_macro(char *arg)
1602 {
1603 	char *eq;
1604 	int err;
1605 
1606 	if ((eq = strchr(arg, '=')) == NULL)
1607 		err = define_macro(arg, "");
1608 	else {
1609 		*eq++ = '\0';
1610 		err = define_macro(arg, eq);
1611 	}
1612 	if (err == -1) {
1613 		syslog(LOG_ERR, "cannot save macro: %m");
1614 		exit(1);
1615 	}
1616 }
1617 
1618 /*
1619  * Re-implement getsubopt from scratch, because the second argument is broken
1620  * and will not compile with WARNS=5.
1621  */
1622 static int
1623 getsubopt1(char **arg, const char *const *options, char **valp, char **optp)
1624 {
1625 	static const char *const delim = ",\t ";
1626 	u_int i;
1627 	char *ptr;
1628 
1629 	*optp = NULL;
1630 
1631 	/* skip leading junk */
1632 	for (ptr = *arg; *ptr != '\0'; ptr++)
1633 		if (strchr(delim, *ptr) == NULL)
1634 			break;
1635 	if (*ptr == '\0') {
1636 		*arg = ptr;
1637 		return (-1);
1638 	}
1639 	*optp = ptr;
1640 
1641 	/* find the end of the option */
1642 	while (*++ptr != '\0')
1643 		if (strchr(delim, *ptr) != NULL || *ptr == '=')
1644 			break;
1645 
1646 	if (*ptr != '\0') {
1647 		if (*ptr == '=') {
1648 			*ptr++ = '\0';
1649 			*valp = ptr;
1650 			while (*ptr != '\0' && strchr(delim, *ptr) == NULL)
1651 				ptr++;
1652 			if (*ptr != '\0')
1653 				*ptr++ = '\0';
1654 		} else
1655 			*ptr++ = '\0';
1656 	}
1657 
1658 	*arg = ptr;
1659 
1660 	for (i = 0; *options != NULL; options++, i++)
1661 		if (strcmp(*optp, *options) == 0)
1662 			return (i);
1663 	return (-1);
1664 }
1665 
1666 int
1667 main(int argc, char *argv[])
1668 {
1669 	int opt;
1670 	FILE *fp;
1671 	int background = 1;
1672 	struct tport *p;
1673 	const char *prefix = "snmpd";
1674 	struct lmodule *m;
1675 	char *value = NULL, *option; /* XXX */
1676 	struct transport *t;
1677 
1678 #define DBG_DUMP	0
1679 #define DBG_EVENTS	1
1680 #define DBG_TRACE	2
1681 	static const char *const debug_opts[] = {
1682 		"dump",
1683 		"events",
1684 		"trace",
1685 		NULL
1686 	};
1687 
1688 	snmp_printf = snmp_printf_func;
1689 	snmp_error = snmp_error_func;
1690 	snmp_debug = snmp_debug_func;
1691 	asn_error = asn_error_func;
1692 
1693 	while ((opt = getopt(argc, argv, "c:dD:e:hI:l:m:p:")) != EOF)
1694 		switch (opt) {
1695 
1696 		  case 'c':
1697 			strlcpy(config_file, optarg, sizeof(config_file));
1698 			break;
1699 
1700 		  case 'd':
1701 			background = 0;
1702 			break;
1703 
1704 		  case 'D':
1705 			while (*optarg) {
1706 				switch (getsubopt1(&optarg, debug_opts,
1707 				    &value, &option)) {
1708 
1709 				  case DBG_DUMP:
1710 					debug.dump_pdus = 1;
1711 					break;
1712 
1713 				  case DBG_EVENTS:
1714 					debug.evdebug++;
1715 					break;
1716 
1717 				  case DBG_TRACE:
1718 					if (value == NULL)
1719 						syslog(LOG_ERR,
1720 						    "no value for 'trace'");
1721 					else
1722 						snmp_trace = strtoul(value,
1723 						    NULL, 0);
1724 					break;
1725 
1726 				  case -1:
1727 					if (suboptarg)
1728 						syslog(LOG_ERR,
1729 						    "unknown debug flag '%s'",
1730 						    option);
1731 					else
1732 						syslog(LOG_ERR,
1733 						    "missing debug flag");
1734 					break;
1735 				}
1736 			}
1737 			break;
1738 
1739 		  case 'e':
1740 			strlcpy(engine_file, optarg, sizeof(engine_file));
1741 			break;
1742 		  case 'h':
1743 			fprintf(stderr, "%s", usgtxt);
1744 			exit(0);
1745 
1746 		  case 'I':
1747 			syspath = optarg;
1748 			break;
1749 
1750 		  case 'l':
1751 			prefix = optarg;
1752 			break;
1753 
1754 		  case 'm':
1755 			do_macro(optarg);
1756 			break;
1757 
1758 		  case 'p':
1759 			strlcpy(pid_file, optarg, sizeof(pid_file));
1760 			break;
1761 		}
1762 
1763 	openlog(prefix, LOG_PID | (background ? 0 : LOG_PERROR), LOG_USER);
1764 	setlogmask(LOG_UPTO(debug.logpri - 1));
1765 
1766 	if (background && daemon(0, 0) < 0) {
1767 		syslog(LOG_ERR, "daemon: %m");
1768 		exit(1);
1769 	}
1770 
1771 	argc -= optind;
1772 	argv += optind;
1773 
1774 	progargs = argv;
1775 	nprogargs = argc;
1776 
1777 	srandomdev();
1778 
1779 	snmp_serial_no = random();
1780 
1781 #ifdef USE_TCPWRAPPERS
1782 	/*
1783 	 * Initialize hosts_access(3) handler.
1784 	 */
1785 	request_init(&req, RQ_DAEMON, "snmpd", 0);
1786 	sock_methods(&req);
1787 #endif
1788 
1789 	/*
1790 	 * Initialize the tree.
1791 	 */
1792 	if ((tree = malloc(sizeof(struct snmp_node) * CTREE_SIZE)) == NULL) {
1793 		syslog(LOG_ERR, "%m");
1794 		exit(1);
1795 	}
1796 	memcpy(tree, ctree, sizeof(struct snmp_node) * CTREE_SIZE);
1797 	tree_size = CTREE_SIZE;
1798 
1799 	/*
1800 	 * Get standard communities
1801 	 */
1802 	(void)comm_define(1, "SNMP read", NULL, NULL);
1803 	(void)comm_define(2, "SNMP write", NULL, NULL);
1804 	community = COMM_INITIALIZE;
1805 
1806 	trap_reqid = reqid_allocate(512, NULL);
1807 
1808 	if (config_file[0] == '\0')
1809 		snprintf(config_file, sizeof(config_file), PATH_CONFIG, prefix);
1810 
1811 	init_actvals();
1812 	init_snmpd_engine();
1813 
1814 	this_tick = get_ticks();
1815 	start_tick = this_tick;
1816 
1817 	/* start transports */
1818 	if (atexit(trans_stop) == -1) {
1819 		syslog(LOG_ERR, "atexit failed: %m");
1820 		exit(1);
1821 	}
1822 	if (udp_trans.start() != SNMP_ERR_NOERROR)
1823 		syslog(LOG_WARNING, "cannot start UDP transport");
1824 	if (lsock_trans.start() != SNMP_ERR_NOERROR)
1825 		syslog(LOG_WARNING, "cannot start LSOCK transport");
1826 
1827 #ifdef USE_LIBBEGEMOT
1828 	if (debug.evdebug > 0)
1829 		rpoll_trace = 1;
1830 #else
1831 	if (evCreate(&evctx)) {
1832 		syslog(LOG_ERR, "evCreate: %m");
1833 		exit(1);
1834 	}
1835 	if (debug.evdebug > 0)
1836 		evSetDebug(evctx, 10, stderr);
1837 #endif
1838 
1839 	if (engine_file[0] == '\0')
1840 		snprintf(engine_file, sizeof(engine_file), PATH_ENGINE, prefix);
1841 
1842 	if (read_config(config_file, NULL)) {
1843 		syslog(LOG_ERR, "error in config file");
1844 		exit(1);
1845 	}
1846 
1847 	TAILQ_FOREACH(t, &transport_list, link)
1848 		TAILQ_FOREACH(p, &t->table, link)
1849 			t->vtab->init_port(p);
1850 
1851 	init_sigs();
1852 
1853 	if (pid_file[0] == '\0')
1854 		snprintf(pid_file, sizeof(pid_file), PATH_PID, prefix);
1855 
1856 	if ((fp = fopen(pid_file, "w")) != NULL) {
1857 		fprintf(fp, "%u", getpid());
1858 		fclose(fp);
1859 		if (atexit(term) == -1) {
1860 			syslog(LOG_ERR, "atexit failed: %m");
1861 			(void)remove(pid_file);
1862 			exit(0);
1863 		}
1864 	}
1865 
1866 	if (or_register(&oid_snmpMIB, "The MIB module for SNMPv2 entities.",
1867 	    NULL) == 0) {
1868 		syslog(LOG_ERR, "cannot register SNMPv2 MIB");
1869 		exit(1);
1870 	}
1871 	if (or_register(&oid_begemotSnmpd, "The MIB module for the Begemot SNMPd.",
1872 	    NULL) == 0) {
1873 		syslog(LOG_ERR, "cannot register begemotSnmpd MIB");
1874 		exit(1);
1875 	}
1876 
1877 	while ((m = TAILQ_FIRST(&modules_start)) != NULL) {
1878 		m->flags &= ~LM_ONSTARTLIST;
1879 		TAILQ_REMOVE(&modules_start, m, start);
1880 		lm_start(m);
1881 	}
1882 
1883 	snmp_send_trap(&oid_coldStart, (struct snmp_value *)NULL);
1884 
1885 	for (;;) {
1886 #ifndef USE_LIBBEGEMOT
1887 		evEvent event;
1888 #endif
1889 		struct lmodule *mod;
1890 
1891 		TAILQ_FOREACH(mod, &lmodules, link)
1892 			if (mod->config->idle != NULL)
1893 				(*mod->config->idle)();
1894 
1895 #ifndef USE_LIBBEGEMOT
1896 		if (evGetNext(evctx, &event, EV_WAIT) == 0) {
1897 			if (evDispatch(evctx, event))
1898 				syslog(LOG_ERR, "evDispatch: %m");
1899 		} else if (errno != EINTR) {
1900 			syslog(LOG_ERR, "evGetNext: %m");
1901 			exit(1);
1902 		}
1903 #else
1904 		poll_dispatch(1);
1905 #endif
1906 
1907 		if (work != 0) {
1908 			block_sigs();
1909 			if (work & WORK_DOINFO) {
1910 #ifdef USE_LIBBEGEMOT
1911 				info_func();
1912 #else
1913 				if (evWaitFor(evctx, &work, info_func,
1914 				    NULL, NULL) == -1) {
1915 					syslog(LOG_ERR, "evWaitFor: %m");
1916 					exit(1);
1917 				}
1918 #endif
1919 			}
1920 			if (work & WORK_RECONFIG) {
1921 #ifdef USE_LIBBEGEMOT
1922 				config_func();
1923 #else
1924 				if (evWaitFor(evctx, &work, config_func,
1925 				    NULL, NULL) == -1) {
1926 					syslog(LOG_ERR, "evWaitFor: %m");
1927 					exit(1);
1928 				}
1929 #endif
1930 			}
1931 			work = 0;
1932 			unblock_sigs();
1933 #ifndef USE_LIBBEGEMOT
1934 			if (evDo(evctx, &work) == -1) {
1935 				syslog(LOG_ERR, "evDo: %m");
1936 				exit(1);
1937 			}
1938 #endif
1939 		}
1940 	}
1941 
1942 	return (0);
1943 }
1944 
1945 uint64_t
1946 get_ticks(void)
1947 {
1948 	struct timeval tv;
1949 	uint64_t ret;
1950 
1951 	if (gettimeofday(&tv, NULL))
1952 		abort();
1953 	ret = tv.tv_sec * 100ULL + tv.tv_usec / 10000ULL;
1954 	return (ret);
1955 }
1956 
1957 /*
1958  * Timer support
1959  */
1960 
1961 /*
1962  * Trampoline for the non-repeatable timers.
1963  */
1964 #ifdef USE_LIBBEGEMOT
1965 static void
1966 tfunc(int tid __unused, void *uap)
1967 #else
1968 static void
1969 tfunc(evContext ctx __unused, void *uap, struct timespec due __unused,
1970 	struct timespec inter __unused)
1971 #endif
1972 {
1973 	struct timer *tp = uap;
1974 
1975 	LIST_REMOVE(tp, link);
1976 	tp->func(tp->udata);
1977 	free(tp);
1978 }
1979 
1980 /*
1981  * Trampoline for the repeatable timers.
1982  */
1983 #ifdef USE_LIBBEGEMOT
1984 static void
1985 trfunc(int tid __unused, void *uap)
1986 #else
1987 static void
1988 trfunc(evContext ctx __unused, void *uap, struct timespec due __unused,
1989 	struct timespec inter __unused)
1990 #endif
1991 {
1992 	struct timer *tp = uap;
1993 
1994 	tp->func(tp->udata);
1995 }
1996 
1997 /*
1998  * Start a one-shot timer
1999  */
2000 void *
2001 timer_start(u_int ticks, void (*func)(void *), void *udata, struct lmodule *mod)
2002 {
2003 	struct timer *tp;
2004 #ifndef USE_LIBBEGEMOT
2005 	struct timespec due;
2006 #endif
2007 
2008 	if ((tp = malloc(sizeof(struct timer))) == NULL) {
2009 		syslog(LOG_CRIT, "out of memory for timer");
2010 		exit(1);
2011 	}
2012 
2013 #ifndef USE_LIBBEGEMOT
2014 	due = evAddTime(evNowTime(),
2015 	    evConsTime(ticks / 100, (ticks % 100) * 10000));
2016 #endif
2017 
2018 	tp->udata = udata;
2019 	tp->owner = mod;
2020 	tp->func = func;
2021 
2022 	LIST_INSERT_HEAD(&timer_list, tp, link);
2023 
2024 #ifdef USE_LIBBEGEMOT
2025 	if ((tp->id = poll_start_timer(ticks * 10, 0, tfunc, tp)) < 0) {
2026 		syslog(LOG_ERR, "cannot set timer: %m");
2027 		exit(1);
2028 	}
2029 #else
2030 	if (evSetTimer(evctx, tfunc, tp, due, evConsTime(0, 0), &tp->id)
2031 	    == -1) {
2032 		syslog(LOG_ERR, "cannot set timer: %m");
2033 		exit(1);
2034 	}
2035 #endif
2036 	return (tp);
2037 }
2038 
2039 /*
2040  * Start a repeatable timer. When used with USE_LIBBEGEMOT the first argument
2041  * is currently ignored and the initial number of ticks is set to the
2042  * repeat number of ticks.
2043  */
2044 void *
2045 timer_start_repeat(u_int ticks __unused, u_int repeat_ticks,
2046     void (*func)(void *), void *udata, struct lmodule *mod)
2047 {
2048 	struct timer *tp;
2049 #ifndef USE_LIBBEGEMOT
2050 	struct timespec due;
2051 	struct timespec inter;
2052 #endif
2053 
2054 	if ((tp = malloc(sizeof(struct timer))) == NULL) {
2055 		syslog(LOG_CRIT, "out of memory for timer");
2056 		exit(1);
2057 	}
2058 
2059 #ifndef USE_LIBBEGEMOT
2060 	due = evAddTime(evNowTime(),
2061 	    evConsTime(ticks / 100, (ticks % 100) * 10000));
2062 	inter = evConsTime(repeat_ticks / 100, (repeat_ticks % 100) * 10000);
2063 #endif
2064 
2065 	tp->udata = udata;
2066 	tp->owner = mod;
2067 	tp->func = func;
2068 
2069 	LIST_INSERT_HEAD(&timer_list, tp, link);
2070 
2071 #ifdef USE_LIBBEGEMOT
2072 	if ((tp->id = poll_start_timer(repeat_ticks * 10, 1, trfunc, tp)) < 0) {
2073 		syslog(LOG_ERR, "cannot set timer: %m");
2074 		exit(1);
2075 	}
2076 #else
2077 	if (evSetTimer(evctx, trfunc, tp, due, inter, &tp->id) == -1) {
2078 		syslog(LOG_ERR, "cannot set timer: %m");
2079 		exit(1);
2080 	}
2081 #endif
2082 	return (tp);
2083 }
2084 
2085 /*
2086  * Stop a timer.
2087  */
2088 void
2089 timer_stop(void *p)
2090 {
2091 	struct timer *tp = p;
2092 
2093 	LIST_REMOVE(tp, link);
2094 #ifdef USE_LIBBEGEMOT
2095 	poll_stop_timer(tp->id);
2096 #else
2097 	if (evClearTimer(evctx, tp->id) == -1) {
2098 		syslog(LOG_ERR, "cannot stop timer: %m");
2099 		exit(1);
2100 	}
2101 #endif
2102 	free(p);
2103 }
2104 
2105 static void
2106 timer_flush(struct lmodule *mod)
2107 {
2108 	struct timer *t, *t1;
2109 
2110 	t = LIST_FIRST(&timer_list);
2111 	while (t != NULL) {
2112 		t1 = LIST_NEXT(t, link);
2113 		if (t->owner == mod)
2114 			timer_stop(t);
2115 		t = t1;
2116 	}
2117 }
2118 
2119 static void
2120 snmp_printf_func(const char *fmt, ...)
2121 {
2122 	va_list ap;
2123 	static char *pend = NULL;
2124 	char *ret, *new;
2125 
2126 	va_start(ap, fmt);
2127 	vasprintf(&ret, fmt, ap);
2128 	va_end(ap);
2129 
2130 	if (ret == NULL)
2131 		return;
2132 	if (pend != NULL) {
2133 		if ((new = realloc(pend, strlen(pend) + strlen(ret) + 1))
2134 		    == NULL) {
2135 			free(ret);
2136 			return;
2137 		}
2138 		pend = new;
2139 		strcat(pend, ret);
2140 		free(ret);
2141 	} else
2142 		pend = ret;
2143 
2144 	while ((ret = strchr(pend, '\n')) != NULL) {
2145 		*ret = '\0';
2146 		syslog(LOG_DEBUG, "%s", pend);
2147 		if (strlen(ret + 1) == 0) {
2148 			free(pend);
2149 			pend = NULL;
2150 			break;
2151 		}
2152 		strcpy(pend, ret + 1);
2153 	}
2154 }
2155 
2156 static void
2157 snmp_error_func(const char *err, ...)
2158 {
2159 	char errbuf[1000];
2160 	va_list ap;
2161 
2162 	if (!(snmp_trace & LOG_SNMP_ERRORS))
2163 		return;
2164 
2165 	va_start(ap, err);
2166 	snprintf(errbuf, sizeof(errbuf), "SNMP: ");
2167 	vsnprintf(errbuf + strlen(errbuf),
2168 	    sizeof(errbuf) - strlen(errbuf), err, ap);
2169 	va_end(ap);
2170 
2171 	syslog(LOG_ERR, "%s", errbuf);
2172 }
2173 
2174 static void
2175 snmp_debug_func(const char *err, ...)
2176 {
2177 	char errbuf[1000];
2178 	va_list ap;
2179 
2180 	va_start(ap, err);
2181 	snprintf(errbuf, sizeof(errbuf), "SNMP: ");
2182 	vsnprintf(errbuf+strlen(errbuf), sizeof(errbuf)-strlen(errbuf),
2183 	    err, ap);
2184 	va_end(ap);
2185 
2186 	syslog(LOG_DEBUG, "%s", errbuf);
2187 }
2188 
2189 static void
2190 asn_error_func(const struct asn_buf *b, const char *err, ...)
2191 {
2192 	char errbuf[1000];
2193 	va_list ap;
2194 	u_int i;
2195 
2196 	if (!(snmp_trace & LOG_ASN1_ERRORS))
2197 		return;
2198 
2199 	va_start(ap, err);
2200 	snprintf(errbuf, sizeof(errbuf), "ASN.1: ");
2201 	vsnprintf(errbuf + strlen(errbuf),
2202 	    sizeof(errbuf) - strlen(errbuf), err, ap);
2203 	va_end(ap);
2204 
2205 	if (b != NULL) {
2206 		snprintf(errbuf + strlen(errbuf),
2207 		    sizeof(errbuf) - strlen(errbuf), " at");
2208 		for (i = 0; b->asn_len > i; i++)
2209 			snprintf(errbuf + strlen(errbuf),
2210 			    sizeof(errbuf) - strlen(errbuf),
2211 			    " %02x", b->asn_cptr[i]);
2212 	}
2213 
2214 	syslog(LOG_ERR, "%s", errbuf);
2215 }
2216 
2217 /*
2218  * Create a new community
2219  */
2220 u_int
2221 comm_define(u_int priv, const char *descr, struct lmodule *owner,
2222     const char *str)
2223 {
2224 	struct community *c, *p;
2225 	u_int ncomm;
2226 
2227 	/* generate an identifier */
2228 	do {
2229 		if ((ncomm = next_community_index++) == UINT_MAX)
2230 			next_community_index = 1;
2231 		TAILQ_FOREACH(c, &community_list, link)
2232 			if (c->value == ncomm)
2233 				break;
2234 	} while (c != NULL);
2235 
2236 	if ((c = malloc(sizeof(struct community))) == NULL) {
2237 		syslog(LOG_ERR, "comm_define: %m");
2238 		return (0);
2239 	}
2240 	c->owner = owner;
2241 	c->value = ncomm;
2242 	c->descr = descr;
2243 	c->string = NULL;
2244 	c->private = priv;
2245 
2246 	if (str != NULL) {
2247 		if((c->string = malloc(strlen(str)+1)) == NULL) {
2248 			free(c);
2249 			return (0);
2250 		}
2251 		strcpy(c->string, str);
2252 	}
2253 
2254 	/* make index */
2255 	if (c->owner == NULL) {
2256 		c->index.len = 1;
2257 		c->index.subs[0] = 0;
2258 	} else {
2259 		c->index = c->owner->index;
2260 	}
2261 	c->index.subs[c->index.len++] = c->private;
2262 
2263 	/*
2264 	 * Insert ordered
2265 	 */
2266 	TAILQ_FOREACH(p, &community_list, link) {
2267 		if (asn_compare_oid(&p->index, &c->index) > 0) {
2268 			TAILQ_INSERT_BEFORE(p, c, link);
2269 			break;
2270 		}
2271 	}
2272 	if (p == NULL)
2273 		TAILQ_INSERT_TAIL(&community_list, c, link);
2274 	return (c->value);
2275 }
2276 
2277 const char *
2278 comm_string(u_int ncomm)
2279 {
2280 	struct community *p;
2281 
2282 	TAILQ_FOREACH(p, &community_list, link)
2283 		if (p->value == ncomm)
2284 			return (p->string);
2285 	return (NULL);
2286 }
2287 
2288 /*
2289  * Delete all communities allocated by a module
2290  */
2291 static void
2292 comm_flush(struct lmodule *mod)
2293 {
2294 	struct community *p, *p1;
2295 
2296 	p = TAILQ_FIRST(&community_list);
2297 	while (p != NULL) {
2298 		p1 = TAILQ_NEXT(p, link);
2299 		if (p->owner == mod) {
2300 			free(p->string);
2301 			TAILQ_REMOVE(&community_list, p, link);
2302 			free(p);
2303 		}
2304 		p = p1;
2305 	}
2306 }
2307 
2308 /*
2309  * Request ID handling.
2310  *
2311  * Allocate a new range of request ids. Use a first fit algorithm.
2312  */
2313 u_int
2314 reqid_allocate(int size, struct lmodule *mod)
2315 {
2316 	u_int type;
2317 	struct idrange *r, *r1;
2318 
2319 	if (size <= 0 || size > INT32_MAX) {
2320 		syslog(LOG_CRIT, "%s: size out of range: %d", __func__, size);
2321 		return (0);
2322 	}
2323 	/* allocate a type id */
2324 	do {
2325 		if ((type = next_idrange++) == UINT_MAX)
2326 			next_idrange = 1;
2327 		TAILQ_FOREACH(r, &idrange_list, link)
2328 			if (r->type == type)
2329 				break;
2330 	} while(r != NULL);
2331 
2332 	/* find a range */
2333 	if (TAILQ_EMPTY(&idrange_list))
2334 		r = NULL;
2335 	else {
2336 		r = TAILQ_FIRST(&idrange_list);
2337 		if (r->base < size) {
2338 			while((r1 = TAILQ_NEXT(r, link)) != NULL) {
2339 				if (r1->base - (r->base + r->size) >= size)
2340 					break;
2341 				r = r1;
2342 			}
2343 			r = r1;
2344 		}
2345 		if (r == NULL) {
2346 			r1 = TAILQ_LAST(&idrange_list, idrange_list);
2347 			if (INT32_MAX - size + 1 < r1->base + r1->size) {
2348 				syslog(LOG_ERR, "out of id ranges (%u)", size);
2349 				return (0);
2350 			}
2351 		}
2352 	}
2353 
2354 	/* allocate structure */
2355 	if ((r1 = malloc(sizeof(struct idrange))) == NULL) {
2356 		syslog(LOG_ERR, "%s: %m", __FUNCTION__);
2357 		return (0);
2358 	}
2359 
2360 	r1->type = type;
2361 	r1->size = size;
2362 	r1->owner = mod;
2363 	if (TAILQ_EMPTY(&idrange_list) || r == TAILQ_FIRST(&idrange_list)) {
2364 		r1->base = 0;
2365 		TAILQ_INSERT_HEAD(&idrange_list, r1, link);
2366 	} else if (r == NULL) {
2367 		r = TAILQ_LAST(&idrange_list, idrange_list);
2368 		r1->base = r->base + r->size;
2369 		TAILQ_INSERT_TAIL(&idrange_list, r1, link);
2370 	} else {
2371 		r = TAILQ_PREV(r, idrange_list, link);
2372 		r1->base = r->base + r->size;
2373 		TAILQ_INSERT_AFTER(&idrange_list, r, r1, link);
2374 	}
2375 	r1->next = r1->base;
2376 
2377 	return (type);
2378 }
2379 
2380 int32_t
2381 reqid_next(u_int type)
2382 {
2383 	struct idrange *r;
2384 	int32_t id;
2385 
2386 	TAILQ_FOREACH(r, &idrange_list, link)
2387 		if (r->type == type)
2388 			break;
2389 	if (r == NULL) {
2390 		syslog(LOG_CRIT, "wrong idrange type");
2391 		abort();
2392 	}
2393 	if ((id = r->next++) == r->base + (r->size - 1))
2394 		r->next = r->base;
2395 	return (id);
2396 }
2397 
2398 int32_t
2399 reqid_base(u_int type)
2400 {
2401 	struct idrange *r;
2402 
2403 	TAILQ_FOREACH(r, &idrange_list, link)
2404 		if (r->type == type)
2405 			return (r->base);
2406 	syslog(LOG_CRIT, "wrong idrange type");
2407 	abort();
2408 }
2409 
2410 u_int
2411 reqid_type(int32_t reqid)
2412 {
2413 	struct idrange *r;
2414 
2415 	TAILQ_FOREACH(r, &idrange_list, link)
2416 		if (reqid >= r->base && reqid <= r->base + (r->size - 1))
2417 			return (r->type);
2418 	return (0);
2419 }
2420 
2421 int
2422 reqid_istype(int32_t reqid, u_int type)
2423 {
2424 	return (reqid_type(reqid) == type);
2425 }
2426 
2427 /*
2428  * Delete all communities allocated by a module
2429  */
2430 static void
2431 reqid_flush(struct lmodule *mod)
2432 {
2433 	struct idrange *p, *p1;
2434 
2435 	p = TAILQ_FIRST(&idrange_list);
2436 	while (p != NULL) {
2437 		p1 = TAILQ_NEXT(p, link);
2438 		if (p->owner == mod) {
2439 			TAILQ_REMOVE(&idrange_list, p, link);
2440 			free(p);
2441 		}
2442 		p = p1;
2443 	}
2444 }
2445 
2446 /*
2447  * Merge the given tree for the given module into the main tree.
2448  */
2449 static int
2450 compare_node(const void *v1, const void *v2)
2451 {
2452 	const struct snmp_node *n1 = v1;
2453 	const struct snmp_node *n2 = v2;
2454 
2455 	return (asn_compare_oid(&n1->oid, &n2->oid));
2456 }
2457 static int
2458 tree_merge(const struct snmp_node *ntree, u_int nsize, struct lmodule *mod)
2459 {
2460 	struct snmp_node *xtree;
2461 	u_int i;
2462 
2463 	xtree = realloc(tree, sizeof(*tree) * (tree_size + nsize));
2464 	if (xtree == NULL) {
2465 		syslog(LOG_ERR, "tree_merge: %m");
2466 		return (-1);
2467 	}
2468 	tree = xtree;
2469 	memcpy(&tree[tree_size], ntree, sizeof(*tree) * nsize);
2470 
2471 	for (i = 0; i < nsize; i++)
2472 		tree[tree_size + i].tree_data = mod;
2473 
2474 	tree_size += nsize;
2475 
2476 	qsort(tree, tree_size, sizeof(tree[0]), compare_node);
2477 
2478 	return (0);
2479 }
2480 
2481 /*
2482  * Remove all nodes belonging to the loadable module
2483  */
2484 static void
2485 tree_unmerge(struct lmodule *mod)
2486 {
2487 	u_int s, d;
2488 
2489 	for(s = d = 0; s < tree_size; s++)
2490 		if (tree[s].tree_data != mod) {
2491 			if (s != d)
2492 				tree[d] = tree[s];
2493 			d++;
2494 		}
2495 	tree_size = d;
2496 }
2497 
2498 /*
2499  * Loadable modules
2500  */
2501 struct lmodule *
2502 lm_load(const char *path, const char *section)
2503 {
2504 	struct lmodule *m;
2505 	int err;
2506 	int i;
2507 	char *av[MAX_MOD_ARGS + 1];
2508 	int ac;
2509 	u_int u;
2510 
2511 	if ((m = malloc(sizeof(*m))) == NULL) {
2512 		syslog(LOG_ERR, "lm_load: %m");
2513 		return (NULL);
2514 	}
2515 	m->handle = NULL;
2516 	m->flags = 0;
2517 	strcpy(m->section, section);
2518 
2519 	if ((m->path = malloc(strlen(path) + 1)) == NULL) {
2520 		syslog(LOG_ERR, "lm_load: %m");
2521 		goto err;
2522 	}
2523 	strcpy(m->path, path);
2524 
2525 	/*
2526 	 * Make index
2527 	 */
2528 	m->index.subs[0] = strlen(section);
2529 	m->index.len = m->index.subs[0] + 1;
2530 	for (u = 0; u < m->index.subs[0]; u++)
2531 		m->index.subs[u + 1] = section[u];
2532 
2533 	/*
2534 	 * Load the object file and locate the config structure
2535 	 */
2536 	if ((m->handle = dlopen(m->path, RTLD_NOW|RTLD_GLOBAL)) == NULL) {
2537 		syslog(LOG_ERR, "lm_load: open %s", dlerror());
2538 		goto err;
2539 	}
2540 
2541 	if ((m->config = dlsym(m->handle, "config")) == NULL) {
2542 		syslog(LOG_ERR, "lm_load: no 'config' symbol %s", dlerror());
2543 		goto err;
2544 	}
2545 
2546 	/*
2547 	 * Insert it into the right place
2548 	 */
2549 	INSERT_OBJECT_OID(m, &lmodules);
2550 
2551 	/* preserve order */
2552 	if (community == COMM_INITIALIZE) {
2553 		m->flags |= LM_ONSTARTLIST;
2554 		TAILQ_INSERT_TAIL(&modules_start, m, start);
2555 	}
2556 
2557 	/*
2558 	 * make the argument vector.
2559 	 */
2560 	ac = 0;
2561 	for (i = 0; i < nprogargs; i++) {
2562 		if (strlen(progargs[i]) >= strlen(section) + 1 &&
2563 		    strncmp(progargs[i], section, strlen(section)) == 0 &&
2564 		    progargs[i][strlen(section)] == ':') {
2565 			if (ac == MAX_MOD_ARGS) {
2566 				syslog(LOG_WARNING, "too many arguments for "
2567 				    "module '%s", section);
2568 				break;
2569 			}
2570 			av[ac++] = &progargs[i][strlen(section)+1];
2571 		}
2572 	}
2573 	av[ac] = NULL;
2574 
2575 	/*
2576 	 * Run the initialization function
2577 	 */
2578 	if ((err = (*m->config->init)(m, ac, av)) != 0) {
2579 		syslog(LOG_ERR, "lm_load: init failed: %d", err);
2580 		TAILQ_REMOVE(&lmodules, m, link);
2581 		goto err;
2582 	}
2583 
2584 	return (m);
2585 
2586   err:
2587 	if ((m->flags & LM_ONSTARTLIST) != 0)
2588 		TAILQ_REMOVE(&modules_start, m, start);
2589 	if (m->handle)
2590 		dlclose(m->handle);
2591 	free(m->path);
2592 	free(m);
2593 	return (NULL);
2594 }
2595 
2596 /*
2597  * Start a module
2598  */
2599 void
2600 lm_start(struct lmodule *mod)
2601 {
2602 	const struct lmodule *m;
2603 
2604 	/*
2605 	 * Merge tree. If this fails, unload the module.
2606 	 */
2607 	if (tree_merge(mod->config->tree, mod->config->tree_size, mod)) {
2608 		lm_unload(mod);
2609 		return;
2610 	}
2611 
2612 	/*
2613 	 * Read configuration
2614 	 */
2615 	if (read_config(config_file, mod)) {
2616 		syslog(LOG_ERR, "error in config file");
2617 		lm_unload(mod);
2618 		return;
2619 	}
2620 	if (mod->config->start)
2621 		(*mod->config->start)();
2622 
2623 	mod->flags |= LM_STARTED;
2624 
2625 	/*
2626 	 * Inform other modules
2627 	 */
2628 	TAILQ_FOREACH(m, &lmodules, link)
2629 		if (m->config->loading)
2630 			(*m->config->loading)(mod, 1);
2631 }
2632 
2633 
2634 /*
2635  * Unload a module.
2636  */
2637 void
2638 lm_unload(struct lmodule *m)
2639 {
2640 	int err;
2641 	const struct lmodule *mod;
2642 
2643 	TAILQ_REMOVE(&lmodules, m, link);
2644 	if (m->flags & LM_ONSTARTLIST)
2645 		TAILQ_REMOVE(&modules_start, m, start);
2646 	tree_unmerge(m);
2647 
2648 	if ((m->flags & LM_STARTED) && m->config->fini &&
2649 	    (err = (*m->config->fini)()) != 0)
2650 		syslog(LOG_WARNING, "lm_unload(%s): fini %d", m->section, err);
2651 
2652 	comm_flush(m);
2653 	reqid_flush(m);
2654 	timer_flush(m);
2655 	fd_flush(m);
2656 
2657 	dlclose(m->handle);
2658 	free(m->path);
2659 
2660 	/*
2661 	 * Inform other modules
2662 	 */
2663 	TAILQ_FOREACH(mod, &lmodules, link)
2664 		if (mod->config->loading)
2665 			(*mod->config->loading)(m, 0);
2666 
2667 	free(m);
2668 }
2669 
2670 /*
2671  * Register an object resource and return the index (or 0 on failures)
2672  */
2673 u_int
2674 or_register(const struct asn_oid *or, const char *descr, struct lmodule *mod)
2675 {
2676 	struct objres *objres, *or1;
2677 	u_int idx;
2678 
2679 	/* find a free index */
2680 	idx = 1;
2681 	for (objres = TAILQ_FIRST(&objres_list);
2682 	     objres != NULL;
2683 	     objres = TAILQ_NEXT(objres, link)) {
2684 		if ((or1 = TAILQ_NEXT(objres, link)) == NULL ||
2685 		    or1->index > objres->index + 1) {
2686 			idx = objres->index + 1;
2687 			break;
2688 		}
2689 	}
2690 
2691 	if ((objres = malloc(sizeof(*objres))) == NULL)
2692 		return (0);
2693 
2694 	objres->index = idx;
2695 	objres->oid = *or;
2696 	strlcpy(objres->descr, descr, sizeof(objres->descr));
2697 	objres->uptime = (uint32_t)(get_ticks() - start_tick);
2698 	objres->module = mod;
2699 
2700 	INSERT_OBJECT_INT(objres, &objres_list);
2701 
2702 	systemg.or_last_change = objres->uptime;
2703 
2704 	return (idx);
2705 }
2706 
2707 void
2708 or_unregister(u_int idx)
2709 {
2710 	struct objres *objres;
2711 
2712 	TAILQ_FOREACH(objres, &objres_list, link)
2713 		if (objres->index == idx) {
2714 			TAILQ_REMOVE(&objres_list, objres, link);
2715 			free(objres);
2716 			return;
2717 		}
2718 }
2719 
2720 /*
2721  * RFC 3414 User-based Security Model support
2722  */
2723 
2724 struct snmpd_usmstat *
2725 bsnmpd_get_usm_stats(void)
2726 {
2727 	return (&snmpd_usmstats);
2728 }
2729 
2730 void
2731 bsnmpd_reset_usm_stats(void)
2732 {
2733 	memset(&snmpd_usmstats, 0, sizeof(snmpd_usmstats));
2734 }
2735 
2736 struct usm_user *
2737 usm_first_user(void)
2738 {
2739 	return (SLIST_FIRST(&usm_userlist));
2740 }
2741 
2742 struct usm_user *
2743 usm_next_user(struct usm_user *uuser)
2744 {
2745 	if (uuser == NULL)
2746 		return (NULL);
2747 
2748 	return (SLIST_NEXT(uuser, up));
2749 }
2750 
2751 struct usm_user *
2752 usm_find_user(uint8_t *engine, uint32_t elen, char *uname)
2753 {
2754 	struct usm_user *uuser;
2755 
2756 	SLIST_FOREACH(uuser, &usm_userlist, up)
2757 		if (uuser->user_engine_len == elen &&
2758 		    memcmp(uuser->user_engine_id, engine, elen) == 0 &&
2759 		    strlen(uuser->suser.sec_name) == strlen(uname) &&
2760 		    strcmp(uuser->suser.sec_name, uname) == 0)
2761 			break;
2762 
2763 	return (uuser);
2764 }
2765 
2766 static int
2767 usm_compare_user(struct usm_user *u1, struct usm_user *u2)
2768 {
2769 	uint32_t i;
2770 
2771 	if (u1->user_engine_len < u2->user_engine_len)
2772 		return (-1);
2773 	if (u1->user_engine_len > u2->user_engine_len)
2774 		return (1);
2775 
2776 	for (i = 0; i < u1->user_engine_len; i++) {
2777 		if (u1->user_engine_id[i] < u2->user_engine_id[i])
2778 			return (-1);
2779 		if (u1->user_engine_id[i] > u2->user_engine_id[i])
2780 			return (1);
2781 	}
2782 
2783 	if (strlen(u1->suser.sec_name) < strlen(u2->suser.sec_name))
2784 		return (-1);
2785 	if (strlen(u1->suser.sec_name) > strlen(u2->suser.sec_name))
2786 		return (1);
2787 
2788 	for (i = 0; i < strlen(u1->suser.sec_name); i++) {
2789 		if (u1->suser.sec_name[i] < u2->suser.sec_name[i])
2790 			return (-1);
2791 		if (u1->suser.sec_name[i] > u2->suser.sec_name[i])
2792 			return (1);
2793 	}
2794 
2795 	return (0);
2796 }
2797 
2798 struct usm_user *
2799 usm_new_user(uint8_t *eid, uint32_t elen, char *uname)
2800 {
2801 	int cmp;
2802 	struct usm_user *uuser, *temp, *prev;
2803 
2804 	for (uuser = usm_first_user(); uuser != NULL;
2805 	    (uuser = usm_next_user(uuser))) {
2806 		if (uuser->user_engine_len == elen &&
2807 		    strlen(uname) == strlen(uuser->suser.sec_name) &&
2808 		    strcmp(uname, uuser->suser.sec_name) == 0 &&
2809 		    memcmp(eid, uuser->user_engine_id, elen) == 0)
2810 			return (NULL);
2811 	}
2812 
2813 	if ((uuser = (struct usm_user *)malloc(sizeof(*uuser))) == NULL)
2814 		return (NULL);
2815 
2816 	memset(uuser, 0, sizeof(*uuser));
2817 	strlcpy(uuser->suser.sec_name, uname, SNMP_ADM_STR32_SIZ);
2818 	memcpy(uuser->user_engine_id, eid, elen);
2819 	uuser->user_engine_len = elen;
2820 
2821 	if ((prev = SLIST_FIRST(&usm_userlist)) == NULL ||
2822 	    usm_compare_user(uuser, prev) < 0) {
2823 		SLIST_INSERT_HEAD(&usm_userlist, uuser, up);
2824 		return (uuser);
2825 	}
2826 
2827 	SLIST_FOREACH(temp, &usm_userlist, up) {
2828 		if ((cmp = usm_compare_user(uuser, temp)) <= 0)
2829 			break;
2830 		prev = temp;
2831 	}
2832 
2833 	if (temp == NULL || cmp < 0)
2834 		SLIST_INSERT_AFTER(prev, uuser, up);
2835 	else if (cmp > 0)
2836 		SLIST_INSERT_AFTER(temp, uuser, up);
2837 	else {
2838 		syslog(LOG_ERR, "User %s exists", uuser->suser.sec_name);
2839 		free(uuser);
2840 		return (NULL);
2841 	}
2842 
2843 	return (uuser);
2844 }
2845 
2846 void
2847 usm_delete_user(struct usm_user *uuser)
2848 {
2849 	SLIST_REMOVE(&usm_userlist, uuser, usm_user, up);
2850 	free(uuser);
2851 }
2852 
2853 void
2854 usm_flush_users(void)
2855 {
2856 	struct usm_user *uuser;
2857 
2858 	while ((uuser = SLIST_FIRST(&usm_userlist)) != NULL) {
2859 		SLIST_REMOVE_HEAD(&usm_userlist, up);
2860 		free(uuser);
2861 	}
2862 
2863 	SLIST_INIT(&usm_userlist);
2864 }
2865 
2866 /*
2867  * RFC 3415 View-based Access Control Model support
2868  */
2869 struct vacm_user *
2870 vacm_first_user(void)
2871 {
2872 	return (SLIST_FIRST(&vacm_userlist));
2873 }
2874 
2875 struct vacm_user *
2876 vacm_next_user(struct vacm_user *vuser)
2877 {
2878 	if (vuser == NULL)
2879 		return (NULL);
2880 
2881 	return (SLIST_NEXT(vuser, vvu));
2882 }
2883 
2884 static int
2885 vacm_compare_user(struct vacm_user *v1, struct vacm_user *v2)
2886 {
2887 	uint32_t i;
2888 
2889 	if (v1->sec_model < v2->sec_model)
2890 		return (-1);
2891 	if (v1->sec_model > v2->sec_model)
2892 		return (1);
2893 
2894 	if (strlen(v1->secname) < strlen(v2->secname))
2895 		return (-1);
2896 	if (strlen(v1->secname) > strlen(v2->secname))
2897 		return (1);
2898 
2899 	for (i = 0; i < strlen(v1->secname); i++) {
2900 		if (v1->secname[i] < v2->secname[i])
2901 			return (-1);
2902 		if (v1->secname[i] > v2->secname[i])
2903 			return (1);
2904 	}
2905 
2906 	return (0);
2907 }
2908 
2909 struct vacm_user *
2910 vacm_new_user(int32_t smodel, char *uname)
2911 {
2912 	int cmp;
2913 	struct vacm_user *user, *temp, *prev;
2914 
2915 	SLIST_FOREACH(user, &vacm_userlist, vvu)
2916 		if (strcmp(uname, user->secname) == 0 &&
2917 		    smodel == user->sec_model)
2918 			return (NULL);
2919 
2920 	if ((user = (struct vacm_user *)malloc(sizeof(*user))) == NULL)
2921 		return (NULL);
2922 
2923 	memset(user, 0, sizeof(*user));
2924 	user->group = &vacm_default_group;
2925 	SLIST_INSERT_HEAD(&vacm_default_group.group_users, user, vvg);
2926 	user->sec_model = smodel;
2927 	strlcpy(user->secname, uname, sizeof(user->secname));
2928 
2929 	if ((prev = SLIST_FIRST(&vacm_userlist)) == NULL ||
2930 	    vacm_compare_user(user, prev) < 0) {
2931 		SLIST_INSERT_HEAD(&vacm_userlist, user, vvu);
2932 		return (user);
2933 	}
2934 
2935 	SLIST_FOREACH(temp, &vacm_userlist, vvu) {
2936 		if ((cmp = vacm_compare_user(user, temp)) <= 0)
2937 			break;
2938 		prev = temp;
2939 	}
2940 
2941 	if (temp == NULL || cmp < 0)
2942 		SLIST_INSERT_AFTER(prev, user, vvu);
2943 	else if (cmp > 0)
2944 		SLIST_INSERT_AFTER(temp, user, vvu);
2945 	else {
2946 		syslog(LOG_ERR, "User %s exists", user->secname);
2947 		free(user);
2948 		return (NULL);
2949 	}
2950 
2951 	return (user);
2952 }
2953 
2954 int
2955 vacm_delete_user(struct vacm_user *user)
2956 {
2957 	if (user->group != NULL && user->group != &vacm_default_group) {
2958 		SLIST_REMOVE(&user->group->group_users, user, vacm_user, vvg);
2959 		if (SLIST_EMPTY(&user->group->group_users)) {
2960 			SLIST_REMOVE(&vacm_grouplist, user->group,
2961 			    vacm_group, vge);
2962 			free(user->group);
2963 		}
2964 	}
2965 
2966 	SLIST_REMOVE(&vacm_userlist, user, vacm_user, vvu);
2967 	free(user);
2968 
2969 	return (0);
2970 }
2971 
2972 int
2973 vacm_user_set_group(struct vacm_user *user, u_char *octets, u_int len)
2974 {
2975 	struct vacm_group *group;
2976 
2977 	if (len >= SNMP_ADM_STR32_SIZ)
2978 		return (-1);
2979 
2980 	SLIST_FOREACH(group, &vacm_grouplist, vge)
2981 		if (strlen(group->groupname) == len &&
2982 		    memcmp(octets, group->groupname, len) == 0)
2983 			break;
2984 
2985 	if (group == NULL) {
2986 		if ((group = (struct vacm_group *)malloc(sizeof(*group))) == NULL)
2987 			return (-1);
2988 		memset(group, 0, sizeof(*group));
2989 		memcpy(group->groupname, octets, len);
2990 		group->groupname[len] = '\0';
2991 		SLIST_INSERT_HEAD(&vacm_grouplist, group, vge);
2992 	}
2993 
2994 	SLIST_REMOVE(&user->group->group_users, user, vacm_user, vvg);
2995 	SLIST_INSERT_HEAD(&group->group_users, user, vvg);
2996 	user->group = group;
2997 
2998 	return (0);
2999 }
3000 
3001 void
3002 vacm_groups_init(void)
3003 {
3004 	SLIST_INSERT_HEAD(&vacm_grouplist, &vacm_default_group, vge);
3005 }
3006 
3007 struct vacm_access *
3008 vacm_first_access_rule(void)
3009 {
3010 	return (TAILQ_FIRST(&vacm_accesslist));
3011 }
3012 
3013 struct vacm_access *
3014 vacm_next_access_rule(struct vacm_access *acl)
3015 {
3016 	if (acl == NULL)
3017 		return (NULL);
3018 
3019 	return (TAILQ_NEXT(acl, vva));
3020 }
3021 
3022 static int
3023 vacm_compare_access_rule(struct vacm_access *v1, struct vacm_access *v2)
3024 {
3025 	uint32_t i;
3026 
3027 	if (strlen(v1->group->groupname) < strlen(v2->group->groupname))
3028 		return (-1);
3029 	if (strlen(v1->group->groupname) > strlen(v2->group->groupname))
3030 		return (1);
3031 
3032 	for (i = 0; i < strlen(v1->group->groupname); i++) {
3033 		if (v1->group->groupname[i] < v2->group->groupname[i])
3034 			return (-1);
3035 		if (v1->group->groupname[i] > v2->group->groupname[i])
3036 			return (1);
3037 	}
3038 
3039 	if (strlen(v1->ctx_prefix) < strlen(v2->ctx_prefix))
3040 		return (-1);
3041 	if (strlen(v1->ctx_prefix) > strlen(v2->ctx_prefix))
3042 		return (1);
3043 
3044 	for (i = 0; i < strlen(v1->ctx_prefix); i++) {
3045 		if (v1->ctx_prefix[i] < v2->ctx_prefix[i])
3046 			return (-1);
3047 		if (v1->ctx_prefix[i] > v2->ctx_prefix[i])
3048 			return (1);
3049 	}
3050 
3051 	if (v1->sec_model < v2->sec_model)
3052 		return (-1);
3053 	if (v1->sec_model > v2->sec_model)
3054 		return (1);
3055 
3056 	if (v1->sec_level < v2->sec_level)
3057 		return (-1);
3058 	if (v1->sec_level > v2->sec_level)
3059 		return (1);
3060 
3061 	return (0);
3062 }
3063 
3064 struct vacm_access *
3065 vacm_new_access_rule(char *gname, char *cprefix, int32_t smodel, int32_t slevel)
3066 {
3067 	struct vacm_group *group;
3068 	struct vacm_access *acl, *temp;
3069 
3070 	TAILQ_FOREACH(acl, &vacm_accesslist, vva) {
3071 		if (acl->group == NULL)
3072 			continue;
3073 		if (strcmp(gname, acl->group->groupname) == 0 &&
3074 		    strcmp(cprefix, acl->ctx_prefix) == 0 &&
3075 		    acl->sec_model == smodel && acl->sec_level == slevel)
3076 			return (NULL);
3077 	}
3078 
3079 	/* Make sure the group exists */
3080 	SLIST_FOREACH(group, &vacm_grouplist, vge)
3081 		if (strcmp(gname, group->groupname) == 0)
3082 			break;
3083 
3084 	if (group == NULL)
3085 		return (NULL);
3086 
3087 	if ((acl = (struct vacm_access *)malloc(sizeof(*acl))) == NULL)
3088 		return (NULL);
3089 
3090 	memset(acl, 0, sizeof(*acl));
3091 	acl->group = group;
3092 	strlcpy(acl->ctx_prefix, cprefix, sizeof(acl->ctx_prefix));
3093 	acl->sec_model = smodel;
3094 	acl->sec_level = slevel;
3095 
3096 	if ((temp = TAILQ_FIRST(&vacm_accesslist)) == NULL ||
3097 	    vacm_compare_access_rule(acl, temp) < 0) {
3098 		TAILQ_INSERT_HEAD(&vacm_accesslist, acl, vva);
3099 		return (acl);
3100 	}
3101 
3102 	TAILQ_FOREACH(temp, &vacm_accesslist, vva)
3103 		if (vacm_compare_access_rule(acl, temp) < 0) {
3104 		    	TAILQ_INSERT_BEFORE(temp, acl, vva);
3105 			return (acl);
3106 		}
3107 
3108 	TAILQ_INSERT_TAIL(&vacm_accesslist, acl, vva);
3109 
3110 	return (acl);
3111 }
3112 
3113 int
3114 vacm_delete_access_rule(struct vacm_access *acl)
3115 {
3116 	TAILQ_REMOVE(&vacm_accesslist, acl, vva);
3117 	free(acl);
3118 
3119 	return (0);
3120 }
3121 
3122 struct vacm_view *
3123 vacm_first_view(void)
3124 {
3125 	return (SLIST_FIRST(&vacm_viewlist));
3126 }
3127 
3128 struct vacm_view *
3129 vacm_next_view(struct vacm_view *view)
3130 {
3131 	if (view == NULL)
3132 		return (NULL);
3133 
3134 	return (SLIST_NEXT(view, vvl));
3135 }
3136 
3137 static int
3138 vacm_compare_view(struct vacm_view *v1, struct vacm_view *v2)
3139 {
3140 	uint32_t i;
3141 
3142 	if (strlen(v1->viewname) < strlen(v2->viewname))
3143 		return (-1);
3144 	if (strlen(v1->viewname) > strlen(v2->viewname))
3145 		return (1);
3146 
3147 	for (i = 0; i < strlen(v1->viewname); i++) {
3148 		if (v1->viewname[i] < v2->viewname[i])
3149 			return (-1);
3150 		if (v1->viewname[i] > v2->viewname[i])
3151 			return (1);
3152 	}
3153 
3154 	return (asn_compare_oid(&v1->subtree, &v2->subtree));
3155 }
3156 
3157 struct vacm_view *
3158 vacm_new_view(char *vname, struct asn_oid *oid)
3159 {
3160 	int cmp;
3161 	struct vacm_view *view, *temp, *prev;
3162 
3163 	SLIST_FOREACH(view, &vacm_viewlist, vvl)
3164 		if (strcmp(vname, view->viewname) == 0)
3165 			return (NULL);
3166 
3167 	if ((view = (struct vacm_view *)malloc(sizeof(*view))) == NULL)
3168 		return (NULL);
3169 
3170 	memset(view, 0, sizeof(*view));
3171 	strlcpy(view->viewname, vname, sizeof(view->viewname));
3172 	asn_append_oid(&view->subtree, oid);
3173 
3174 	if ((prev = SLIST_FIRST(&vacm_viewlist)) == NULL ||
3175 	    vacm_compare_view(view, prev) < 0) {
3176 		SLIST_INSERT_HEAD(&vacm_viewlist, view, vvl);
3177 		return (view);
3178 	}
3179 
3180 	SLIST_FOREACH(temp, &vacm_viewlist, vvl) {
3181 		if ((cmp = vacm_compare_view(view, temp)) <= 0)
3182 			break;
3183 		prev = temp;
3184 	}
3185 
3186 	if (temp == NULL || cmp < 0)
3187 		SLIST_INSERT_AFTER(prev, view, vvl);
3188 	else if (cmp > 0)
3189 		SLIST_INSERT_AFTER(temp, view, vvl);
3190 	else {
3191 		syslog(LOG_ERR, "View %s exists", view->viewname);
3192 		free(view);
3193 		return (NULL);
3194 	}
3195 
3196 	return (view);
3197 }
3198 
3199 int
3200 vacm_delete_view(struct vacm_view *view)
3201 {
3202 	SLIST_REMOVE(&vacm_viewlist, view, vacm_view, vvl);
3203 	free(view);
3204 
3205 	return (0);
3206 }
3207 
3208 struct vacm_context *
3209 vacm_first_context(void)
3210 {
3211 	return (SLIST_FIRST(&vacm_contextlist));
3212 }
3213 
3214 struct vacm_context *
3215 vacm_next_context(struct vacm_context *vacmctx)
3216 {
3217 	if (vacmctx == NULL)
3218 		return (NULL);
3219 
3220 	return (SLIST_NEXT(vacmctx, vcl));
3221 }
3222 
3223 struct vacm_context *
3224 vacm_add_context(char *ctxname, int regid)
3225 {
3226 	int cmp;
3227 	struct vacm_context *ctx, *temp, *prev;
3228 
3229 	SLIST_FOREACH(ctx, &vacm_contextlist, vcl)
3230 		if (strcmp(ctxname, ctx->ctxname) == 0) {
3231 			syslog(LOG_ERR, "Context %s exists", ctx->ctxname);
3232 			return (NULL);
3233 		}
3234 
3235 	if ((ctx = (struct vacm_context *)malloc(sizeof(*ctx))) == NULL)
3236 		return (NULL);
3237 
3238 	memset(ctx, 0, sizeof(*ctx));
3239 	strlcpy(ctx->ctxname, ctxname, sizeof(ctx->ctxname));
3240 	ctx->regid = regid;
3241 
3242 	if ((prev = SLIST_FIRST(&vacm_contextlist)) == NULL ||
3243 	    strlen(ctx->ctxname) < strlen(prev->ctxname) ||
3244 	    strcmp(ctx->ctxname, prev->ctxname) < 0) {
3245 		SLIST_INSERT_HEAD(&vacm_contextlist, ctx, vcl);
3246 		return (ctx);
3247 	}
3248 
3249 	SLIST_FOREACH(temp, &vacm_contextlist, vcl) {
3250 		if (strlen(ctx->ctxname) < strlen(temp->ctxname) ||
3251 		    strcmp(ctx->ctxname, temp->ctxname) < 0) {
3252 		    	cmp = -1;
3253 			break;
3254 		}
3255 		prev = temp;
3256 	}
3257 
3258 	if (temp == NULL || cmp < 0)
3259 		SLIST_INSERT_AFTER(prev, ctx, vcl);
3260 	else if (cmp > 0)
3261 		SLIST_INSERT_AFTER(temp, ctx, vcl);
3262 	else {
3263 		syslog(LOG_ERR, "Context %s exists", ctx->ctxname);
3264 		free(ctx);
3265 		return (NULL);
3266 	}
3267 
3268 	return (ctx);
3269 }
3270 
3271 void
3272 vacm_flush_contexts(int regid)
3273 {
3274 	struct vacm_context *ctx, *temp;
3275 
3276 	SLIST_FOREACH_SAFE(ctx, &vacm_contextlist, vcl, temp)
3277 		if (ctx->regid == regid) {
3278 			SLIST_REMOVE(&vacm_contextlist, ctx, vacm_context, vcl);
3279 			free(ctx);
3280 		}
3281 }
3282