xref: /freebsd/contrib/bsnmp/snmpd/main.c (revision 5dcd9c10612684d1c823670cbb5b4715028784e7)
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 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 struct vacm_userlist vacm_userlist = SLIST_HEAD_INITIALIZER(vacm_userlist);
126 
127 /* A list of all VACM groups */
128 struct vacm_grouplist vacm_grouplist = SLIST_HEAD_INITIALIZER(vacm_grouplist);
129 
130 static struct vacm_group vacm_default_group = {
131 	.groupname = "",
132 };
133 
134 /* The list of configured access entries */
135 struct vacm_accesslist vacm_accesslist = TAILQ_HEAD_INITIALIZER(vacm_accesslist);
136 
137 /* The list of configured views */
138 struct vacm_viewlist vacm_viewlist = SLIST_HEAD_INITIALIZER(vacm_viewlist);
139 
140 /* The list of configured contexts */
141 struct vacm_contextlist vacm_contextlist =
142     SLIST_HEAD_INITIALIZER(vacm_contextlist);
143 
144 /* list of all installed object resources */
145 struct objres_list objres_list = TAILQ_HEAD_INITIALIZER(objres_list);
146 
147 /* community value generator */
148 static u_int next_community_index = 1;
149 
150 /* list of all known ranges */
151 struct idrange_list idrange_list = TAILQ_HEAD_INITIALIZER(idrange_list);
152 
153 /* identifier generator */
154 u_int next_idrange = 1;
155 
156 /* list of all current timers */
157 struct timer_list timer_list = LIST_HEAD_INITIALIZER(timer_list);
158 
159 /* list of file descriptors */
160 struct fdesc_list fdesc_list = LIST_HEAD_INITIALIZER(fdesc_list);
161 
162 /* program arguments */
163 static char **progargs;
164 static int nprogargs;
165 
166 /* current community */
167 u_int	community;
168 static struct community *comm;
169 
170 /* current USM user */
171 struct usm_user *usm_user;
172 
173 /* file names */
174 static char config_file[MAXPATHLEN + 1];
175 static char pid_file[MAXPATHLEN + 1];
176 char engine_file[MAXPATHLEN + 1];
177 
178 #ifndef USE_LIBBEGEMOT
179 /* event context */
180 static evContext evctx;
181 #endif
182 
183 /* signal mask */
184 static sigset_t blocked_sigs;
185 
186 /* signal handling */
187 static int work;
188 #define	WORK_DOINFO	0x0001
189 #define	WORK_RECONFIG	0x0002
190 
191 /* oids */
192 static const struct asn_oid
193 	oid_snmpMIB = OIDX_snmpMIB,
194 	oid_begemotSnmpd = OIDX_begemotSnmpd,
195 	oid_coldStart = OIDX_coldStart,
196 	oid_authenticationFailure = OIDX_authenticationFailure;
197 
198 const struct asn_oid oid_zeroDotZero = { 2, { 0, 0 }};
199 
200 const struct asn_oid oid_usmUnknownEngineIDs =
201 	{ 11, { 1, 3, 6, 1, 6, 3, 15, 1, 1, 4, 0}};
202 
203 const struct asn_oid oid_usmNotInTimeWindows =
204 	{ 11, { 1, 3, 6, 1, 6, 3, 15, 1, 1, 2, 0}};
205 
206 /* request id generator for traps */
207 u_int trap_reqid;
208 
209 /* help text */
210 static const char usgtxt[] = "\
211 Begemot simple SNMP daemon. Copyright (c) 2001-2002 Fraunhofer Institute for\n\
212 Open Communication Systems (FhG Fokus). All rights reserved.\n\
213 Copyright (c) 2010 The FreeBSD Foundation. All rights reserved.\n\
214 usage: snmpd [-dh] [-c file] [-D options] [-e file] [-I path]\n\
215              [-l prefix] [-m variable=value] [-p file]\n\
216 options:\n\
217   -d		don't daemonize\n\
218   -h		print this info\n\
219   -c file	specify configuration file\n\
220   -D options	debugging options\n\
221   -e file	specify engine id file\n\
222   -I path	system include path\n\
223   -l prefix	default basename for pid and config file\n\
224   -m var=val	define variable\n\
225   -p file	specify pid file\n\
226 ";
227 
228 /* hosts_access(3) request */
229 #ifdef USE_TCPWRAPPERS
230 static struct request_info req;
231 #endif
232 
233 /* transports */
234 extern const struct transport_def udp_trans;
235 extern const struct transport_def lsock_trans;
236 
237 struct transport_list transport_list = TAILQ_HEAD_INITIALIZER(transport_list);
238 
239 /* forward declarations */
240 static void snmp_printf_func(const char *fmt, ...);
241 static void snmp_error_func(const char *err, ...);
242 static void snmp_debug_func(const char *err, ...);
243 static void asn_error_func(const struct asn_buf *b, const char *err, ...);
244 
245 /*
246  * Allocate rx/tx buffer. We allocate one byte more for rx.
247  */
248 void *
249 buf_alloc(int tx)
250 {
251 	void *buf;
252 
253 	if ((buf = malloc(tx ? snmpd.txbuf : snmpd.rxbuf)) == NULL) {
254 		syslog(LOG_CRIT, "cannot allocate buffer");
255 		if (tx)
256 			snmpd_stats.noTxbuf++;
257 		else
258 			snmpd_stats.noRxbuf++;
259 		return (NULL);
260 	}
261 	return (buf);
262 }
263 
264 /*
265  * Return the buffer size.
266  */
267 size_t
268 buf_size(int tx)
269 {
270 	return (tx ? snmpd.txbuf : snmpd.rxbuf);
271 }
272 
273 /*
274  * Prepare a PDU for output
275  */
276 void
277 snmp_output(struct snmp_pdu *pdu, u_char *sndbuf, size_t *sndlen,
278     const char *dest)
279 {
280 	struct asn_buf resp_b;
281 
282 	resp_b.asn_ptr = sndbuf;
283 	resp_b.asn_len = snmpd.txbuf;
284 
285 	if (snmp_pdu_encode(pdu, &resp_b) != 0) {
286 		syslog(LOG_ERR, "cannot encode message");
287 		abort();
288 	}
289 	if (debug.dump_pdus) {
290 		snmp_printf("%s <- ", dest);
291 		snmp_pdu_dump(pdu);
292 	}
293 	*sndlen = (size_t)(resp_b.asn_ptr - sndbuf);
294 }
295 
296 /*
297  * Check USM PDU header credentials against local SNMP Engine & users.
298  */
299 static enum snmp_code
300 snmp_pdu_auth_user(struct snmp_pdu *pdu)
301 {
302 	uint64_t etime;
303 	usm_user = NULL;
304 
305 	/* un-authenticated snmpEngineId discovery */
306 	if (pdu->engine.engine_len == 0 && strlen(pdu->user.sec_name) == 0) {
307 		pdu->engine.engine_len = snmpd_engine.engine_len;
308 		memcpy(pdu->engine.engine_id, snmpd_engine.engine_id,
309 		    snmpd_engine.engine_len);
310 		pdu->engine.engine_boots = snmpd_engine.engine_boots;
311 		pdu->engine.engine_time = snmpd_engine.engine_time;
312 		pdu->flags |= SNMP_MSG_AUTODISCOVER;
313 		return (SNMP_CODE_OK);
314 	}
315 
316 	if ((usm_user = usm_find_user(pdu->engine.engine_id,
317 	    pdu->engine.engine_len, pdu->user.sec_name)) == NULL ||
318 	    usm_user->status != 1 /* active */)
319 		return (SNMP_CODE_BADUSER);
320 
321 	if (usm_user->user_engine_len != snmpd_engine.engine_len ||
322 	    memcmp(usm_user->user_engine_id, snmpd_engine.engine_id,
323 	    snmpd_engine.engine_len) != 0)
324 		return (SNMP_CODE_BADENGINE);
325 
326 	pdu->user.priv_proto = usm_user->suser.priv_proto;
327 	memcpy(pdu->user.priv_key, usm_user->suser.priv_key,
328 	    sizeof(pdu->user.priv_key));
329 
330 	/* authenticated snmpEngineId discovery */
331 	if ((pdu->flags & SNMP_MSG_AUTH_FLAG) != 0) {
332 		etime = (get_ticks() - start_tick)  / 100ULL;
333 		if (etime < INT32_MAX)
334 			snmpd_engine.engine_time = etime;
335 		else {
336 			start_tick = get_ticks();
337 			set_snmpd_engine();
338 			snmpd_engine.engine_time = start_tick;
339 		}
340 
341 		pdu->user.auth_proto = usm_user->suser.auth_proto;
342 		memcpy(pdu->user.auth_key, usm_user->suser.auth_key,
343 		    sizeof(pdu->user.auth_key));
344 
345 		if (pdu->engine.engine_boots == 0 &&
346 		    pdu->engine.engine_time == 0) {
347 		    	pdu->flags |= SNMP_MSG_AUTODISCOVER;
348 			return (SNMP_CODE_OK);
349 		}
350 
351 		if (pdu->engine.engine_boots != snmpd_engine.engine_boots ||
352 		    abs(pdu->engine.engine_time - snmpd_engine.engine_time) >
353 		    SNMP_TIME_WINDOW)
354 			return (SNMP_CODE_NOTINTIME);
355 	}
356 
357 	if (((pdu->flags & SNMP_MSG_PRIV_FLAG) != 0 &&
358 	    (pdu->flags & SNMP_MSG_AUTH_FLAG) == 0) ||
359 	    ((pdu->flags & SNMP_MSG_AUTH_FLAG) == 0 &&
360 	    usm_user->suser.auth_proto != SNMP_AUTH_NOAUTH) ||
361 	    ((pdu->flags & SNMP_MSG_PRIV_FLAG) == 0 &&
362 	    usm_user->suser.priv_proto != SNMP_PRIV_NOPRIV))
363 		return (SNMP_CODE_BADSECLEVEL);
364 
365 	return (SNMP_CODE_OK);
366 }
367 
368 /*
369  * Check whether access to each of var bindings in the PDU is allowed based
370  * on the user credentials against the configured User groups & VACM views.
371  */
372 enum snmp_code
373 snmp_pdu_auth_access(struct snmp_pdu *pdu, int32_t *ip)
374 {
375 	const char *uname;
376 	int32_t suboid, smodel;
377 	uint32_t i;
378 	struct vacm_user *vuser;
379 	struct vacm_access *acl;
380 	struct vacm_context *vacmctx;
381 	struct vacm_view *view;
382 
383 	/*
384 	 * At least a default context exists if the snmpd_vacm(3) module is
385 	 * running.
386 	 */
387 	if (SLIST_EMPTY(&vacm_contextlist) ||
388 	    (pdu->flags & SNMP_MSG_AUTODISCOVER) != 0)
389 		return (SNMP_CODE_OK);
390 
391 	switch (pdu->version) {
392 	case SNMP_V1:
393 		if ((uname = comm_string(community)) == NULL)
394 			return (SNMP_CODE_FAILED);
395 		smodel = SNMP_SECMODEL_SNMPv1;
396 		break;
397 
398 	case SNMP_V2c:
399 		if ((uname = comm_string(community)) == NULL)
400 			return (SNMP_CODE_FAILED);
401 		smodel = SNMP_SECMODEL_SNMPv2c;
402 		break;
403 
404 	case SNMP_V3:
405 		uname = pdu->user.sec_name;
406 		if ((smodel = pdu->security_model) !=  SNMP_SECMODEL_USM)
407 			return (SNMP_CODE_FAILED);
408 		/* Compare the PDU context engine id against the agent's */
409 		if (pdu->context_engine_len != snmpd_engine.engine_len ||
410 		    memcmp(pdu->context_engine, snmpd_engine.engine_id,
411 		    snmpd_engine.engine_len) != 0)
412 			return (SNMP_CODE_FAILED);
413 		break;
414 
415 	default:
416 		abort();
417 	}
418 
419 	SLIST_FOREACH(vuser, &vacm_userlist, vvu)
420 		if (strcmp(uname, vuser->secname) == 0 &&
421 		    vuser->sec_model == smodel)
422 			break;
423 
424 	if (vuser == NULL || vuser->group == NULL)
425 		return (SNMP_CODE_FAILED);
426 
427 	/* XXX: shteryana - recheck */
428 	TAILQ_FOREACH_REVERSE(acl, &vacm_accesslist, vacm_accesslist, vva) {
429 		if (acl->group != vuser->group)
430 			continue;
431 		SLIST_FOREACH(vacmctx, &vacm_contextlist, vcl)
432 			if (memcmp(vacmctx->ctxname, acl->ctx_prefix,
433 			    acl->ctx_match) == 0)
434 				goto match;
435 	}
436 
437 	return (SNMP_CODE_FAILED);
438 
439 match:
440 
441 	switch (pdu->type) {
442 	case SNMP_PDU_GET:
443 	case SNMP_PDU_GETNEXT:
444 	case SNMP_PDU_GETBULK:
445 		if ((view = acl->read_view) == NULL)
446 			return (SNMP_CODE_FAILED);
447 		break;
448 
449 	case SNMP_PDU_SET:
450 		if ((view = acl->write_view) == NULL)
451 			return (SNMP_CODE_FAILED);
452 		break;
453 
454 	case SNMP_PDU_TRAP:
455 	case SNMP_PDU_INFORM:
456 	case SNMP_PDU_TRAP2:
457 	case SNMP_PDU_REPORT:
458 		if ((view = acl->notify_view) == NULL)
459 			return (SNMP_CODE_FAILED);
460 		break;
461 	case SNMP_PDU_RESPONSE:
462 		/* NOTREACHED */
463 			return (SNMP_CODE_FAILED);
464 	default:
465 		abort();
466 	}
467 
468 	for (i = 0; i < pdu->nbindings; i++) {
469 		/* XXX - view->mask*/
470 		suboid = asn_is_suboid(&view->subtree, &pdu->bindings[i].var);
471 		if ((!suboid && !view->exclude) || (suboid && view->exclude)) {
472 			*ip = i + 1;
473 			return (SNMP_CODE_FAILED);
474 		}
475 	}
476 
477 	return (SNMP_CODE_OK);
478 }
479 
480 /*
481  * SNMP input. Start: decode the PDU, find the user or community.
482  */
483 enum snmpd_input_err
484 snmp_input_start(const u_char *buf, size_t len, const char *source,
485     struct snmp_pdu *pdu, int32_t *ip, size_t *pdulen)
486 {
487 	struct asn_buf b;
488 	enum snmp_code code;
489 	enum snmpd_input_err ret;
490 	int sret;
491 
492 	/* update uptime */
493 	this_tick = get_ticks();
494 
495 	b.asn_cptr = buf;
496 	b.asn_len = len;
497 
498 	/* look whether we have enough bytes for the entire PDU. */
499 	switch (sret = snmp_pdu_snoop(&b)) {
500 
501 	  case 0:
502 		return (SNMPD_INPUT_TRUNC);
503 
504 	  case -1:
505 		snmpd_stats.inASNParseErrs++;
506 		return (SNMPD_INPUT_FAILED);
507 	}
508 	b.asn_len = *pdulen = (size_t)sret;
509 
510 	memset(pdu, 0, sizeof(*pdu));
511 	if ((code = snmp_pdu_decode_header(&b, pdu)) != SNMP_CODE_OK)
512 		goto decoded;
513 
514 	if (pdu->version == SNMP_V3) {
515 		if (pdu->security_model != SNMP_SECMODEL_USM) {
516 			code = SNMP_CODE_FAILED;
517 			goto decoded;
518 		}
519 		if ((code = snmp_pdu_auth_user(pdu)) != SNMP_CODE_OK)
520 		    	goto decoded;
521 		if ((code =  snmp_pdu_decode_secmode(&b, pdu)) != SNMP_CODE_OK)
522 			goto decoded;
523 	}
524 	code = snmp_pdu_decode_scoped(&b, pdu, ip);
525 
526 	ret = SNMPD_INPUT_OK;
527 
528 decoded:
529 	snmpd_stats.inPkts++;
530 
531 	switch (code) {
532 
533 	  case SNMP_CODE_FAILED:
534 		snmpd_stats.inASNParseErrs++;
535 		return (SNMPD_INPUT_FAILED);
536 
537 	  case SNMP_CODE_BADVERS:
538 	  bad_vers:
539 		snmpd_stats.inBadVersions++;
540 		return (SNMPD_INPUT_FAILED);
541 
542 	  case SNMP_CODE_BADLEN:
543 		if (pdu->type == SNMP_OP_SET)
544 			ret = SNMPD_INPUT_VALBADLEN;
545 		break;
546 
547 	  case SNMP_CODE_OORANGE:
548 		if (pdu->type == SNMP_OP_SET)
549 			ret = SNMPD_INPUT_VALRANGE;
550 		break;
551 
552 	  case SNMP_CODE_BADENC:
553 		if (pdu->type == SNMP_OP_SET)
554 			ret = SNMPD_INPUT_VALBADENC;
555 		break;
556 
557 	  case SNMP_CODE_BADSECLEVEL:
558 		snmpd_usmstats.unsupported_seclevels++;
559 		return (SNMPD_INPUT_FAILED);
560 
561 	  case SNMP_CODE_NOTINTIME:
562 		snmpd_usmstats.not_in_time_windows++;
563 		return (SNMPD_INPUT_FAILED);
564 
565 	  case SNMP_CODE_BADUSER:
566 		snmpd_usmstats.unknown_users++;
567 		return (SNMPD_INPUT_FAILED);
568 
569 	  case SNMP_CODE_BADENGINE:
570 		snmpd_usmstats.unknown_engine_ids++;
571 		return (SNMPD_INPUT_FAILED);
572 
573 	  case SNMP_CODE_BADDIGEST:
574 		snmpd_usmstats.wrong_digests++;
575 		return (SNMPD_INPUT_FAILED);
576 
577 	  case SNMP_CODE_EDECRYPT:
578 		snmpd_usmstats.decrypt_errors++;
579 		return (SNMPD_INPUT_FAILED);
580 
581 	  case SNMP_CODE_OK:
582 		switch (pdu->version) {
583 
584 		  case SNMP_V1:
585 			if (!(snmpd.version_enable & VERS_ENABLE_V1))
586 				goto bad_vers;
587 			break;
588 
589 		  case SNMP_V2c:
590 			if (!(snmpd.version_enable & VERS_ENABLE_V2C))
591 				goto bad_vers;
592 			break;
593 
594 		  case SNMP_V3:
595 		  	if (!(snmpd.version_enable & VERS_ENABLE_V3))
596 				goto bad_vers;
597 			break;
598 
599 		  case SNMP_Verr:
600 			goto bad_vers;
601 		}
602 		break;
603 	}
604 
605 	if (debug.dump_pdus) {
606 		snmp_printf("%s -> ", source);
607 		snmp_pdu_dump(pdu);
608 	}
609 
610 	/*
611 	 * Look, whether we know the community or user
612 	 */
613 
614 	if (pdu->version != SNMP_V3) {
615 		TAILQ_FOREACH(comm, &community_list, link)
616 			if (comm->string != NULL &&
617 			    strcmp(comm->string, pdu->community) == 0)
618 				break;
619 
620 		if (comm == NULL) {
621 			snmpd_stats.inBadCommunityNames++;
622 			snmp_pdu_free(pdu);
623 			if (snmpd.auth_traps)
624 				snmp_send_trap(&oid_authenticationFailure,
625 				    (struct snmp_value *)NULL);
626 			ret = SNMPD_INPUT_BAD_COMM;
627 		} else
628 			community = comm->value;
629 	} else if (pdu->nbindings == 0) {
630 		/* RFC 3414 - snmpEngineID Discovery */
631 		if (strlen(pdu->user.sec_name) == 0) {
632 			asn_append_oid(&(pdu->bindings[pdu->nbindings++].var),
633 			    &oid_usmUnknownEngineIDs);
634 			pdu->context_engine_len = snmpd_engine.engine_len;
635 			memcpy(pdu->context_engine, snmpd_engine.engine_id,
636 			    snmpd_engine.engine_len);
637 		} else if (pdu->engine.engine_boots == 0 &&
638 		    pdu->engine.engine_time == 0) {
639 			asn_append_oid(&(pdu->bindings[pdu->nbindings++].var),
640 			    &oid_usmNotInTimeWindows);
641 			pdu->engine.engine_boots = snmpd_engine.engine_boots;
642 			pdu->engine.engine_time = snmpd_engine.engine_time;
643 		}
644 	} else if (usm_user->suser.auth_proto != SNMP_AUTH_NOAUTH &&
645 	     (pdu->engine.engine_boots == 0 || pdu->engine.engine_time == 0)) {
646 		snmpd_usmstats.not_in_time_windows++;
647 		ret = SNMP_CODE_FAILED;
648 	}
649 
650 	if ((code = snmp_pdu_auth_access(pdu, ip)) != SNMP_CODE_OK)
651 		ret = SNMP_CODE_FAILED;
652 
653 	return (ret);
654 }
655 
656 /*
657  * Will return only _OK or _FAILED
658  */
659 enum snmpd_input_err
660 snmp_input_finish(struct snmp_pdu *pdu, const u_char *rcvbuf, size_t rcvlen,
661     u_char *sndbuf, size_t *sndlen, const char *source,
662     enum snmpd_input_err ierr, int32_t ivar, void *data)
663 {
664 	struct snmp_pdu resp;
665 	struct asn_buf resp_b, pdu_b;
666 	enum snmp_ret ret;
667 
668 	resp_b.asn_ptr = sndbuf;
669 	resp_b.asn_len = snmpd.txbuf;
670 
671 	pdu_b.asn_cptr = rcvbuf;
672 	pdu_b.asn_len = rcvlen;
673 
674 	if (ierr != SNMPD_INPUT_OK) {
675 		/* error decoding the input of a SET */
676 		if (pdu->version == SNMP_V1)
677 			pdu->error_status = SNMP_ERR_BADVALUE;
678 		else if (ierr == SNMPD_INPUT_VALBADLEN)
679 			pdu->error_status = SNMP_ERR_WRONG_LENGTH;
680 		else if (ierr == SNMPD_INPUT_VALRANGE)
681 			pdu->error_status = SNMP_ERR_WRONG_VALUE;
682 		else
683 			pdu->error_status = SNMP_ERR_WRONG_ENCODING;
684 
685 		pdu->error_index = ivar;
686 
687 		if (snmp_make_errresp(pdu, &pdu_b, &resp_b) == SNMP_RET_IGN) {
688 			syslog(LOG_WARNING, "could not encode error response");
689 			snmpd_stats.silentDrops++;
690 			return (SNMPD_INPUT_FAILED);
691 		}
692 
693 		if (debug.dump_pdus) {
694 			snmp_printf("%s <- ", source);
695 			snmp_pdu_dump(pdu);
696 		}
697 		*sndlen = (size_t)(resp_b.asn_ptr - sndbuf);
698 		return (SNMPD_INPUT_OK);
699 	}
700 
701 	switch (pdu->type) {
702 
703 	  case SNMP_PDU_GET:
704 		ret = snmp_get(pdu, &resp_b, &resp, data);
705 		break;
706 
707 	  case SNMP_PDU_GETNEXT:
708 		ret = snmp_getnext(pdu, &resp_b, &resp, data);
709 		break;
710 
711 	  case SNMP_PDU_SET:
712 		ret = snmp_set(pdu, &resp_b, &resp, data);
713 		break;
714 
715 	  case SNMP_PDU_GETBULK:
716 		ret = snmp_getbulk(pdu, &resp_b, &resp, data);
717 		break;
718 
719 	  default:
720 		ret = SNMP_RET_IGN;
721 		break;
722 	}
723 
724 	switch (ret) {
725 
726 	  case SNMP_RET_OK:
727 		/* normal return - send a response */
728 		if (debug.dump_pdus) {
729 			snmp_printf("%s <- ", source);
730 			snmp_pdu_dump(&resp);
731 		}
732 		*sndlen = (size_t)(resp_b.asn_ptr - sndbuf);
733 		snmp_pdu_free(&resp);
734 		return (SNMPD_INPUT_OK);
735 
736 	  case SNMP_RET_IGN:
737 		/* error - send nothing */
738 		snmpd_stats.silentDrops++;
739 		return (SNMPD_INPUT_FAILED);
740 
741 	  case SNMP_RET_ERR:
742 		/* error - send error response. The snmp routine has
743 		 * changed the error fields in the original message. */
744 		resp_b.asn_ptr = sndbuf;
745 		resp_b.asn_len = snmpd.txbuf;
746 		if (snmp_make_errresp(pdu, &pdu_b, &resp_b) == SNMP_RET_IGN) {
747 			syslog(LOG_WARNING, "could not encode error response");
748 			snmpd_stats.silentDrops++;
749 			return (SNMPD_INPUT_FAILED);
750 		} else {
751 			if (debug.dump_pdus) {
752 				snmp_printf("%s <- ", source);
753 				snmp_pdu_dump(pdu);
754 			}
755 			*sndlen = (size_t)(resp_b.asn_ptr - sndbuf);
756 			return (SNMPD_INPUT_OK);
757 		}
758 	}
759 	abort();
760 }
761 
762 /*
763  * Insert a port into the right place in the transport's table of ports
764  */
765 void
766 trans_insert_port(struct transport *t, struct tport *port)
767 {
768 	struct tport *p;
769 
770 	TAILQ_FOREACH(p, &t->table, link) {
771 		if (asn_compare_oid(&p->index, &port->index) > 0) {
772 			TAILQ_INSERT_BEFORE(p, port, link);
773 			return;
774 		}
775 	}
776 	port->transport = t;
777 	TAILQ_INSERT_TAIL(&t->table, port, link);
778 }
779 
780 /*
781  * Remove a port from a transport's list
782  */
783 void
784 trans_remove_port(struct tport *port)
785 {
786 
787 	TAILQ_REMOVE(&port->transport->table, port, link);
788 }
789 
790 /*
791  * Find a port on a transport's list
792  */
793 struct tport *
794 trans_find_port(struct transport *t, const struct asn_oid *idx, u_int sub)
795 {
796 
797 	return (FIND_OBJECT_OID(&t->table, idx, sub));
798 }
799 
800 /*
801  * Find next port on a transport's list
802  */
803 struct tport *
804 trans_next_port(struct transport *t, const struct asn_oid *idx, u_int sub)
805 {
806 
807 	return (NEXT_OBJECT_OID(&t->table, idx, sub));
808 }
809 
810 /*
811  * Return first port
812  */
813 struct tport *
814 trans_first_port(struct transport *t)
815 {
816 
817 	return (TAILQ_FIRST(&t->table));
818 }
819 
820 /*
821  * Iterate through all ports until a function returns a 0.
822  */
823 struct tport *
824 trans_iter_port(struct transport *t, int (*func)(struct tport *, intptr_t),
825     intptr_t arg)
826 {
827 	struct tport *p;
828 
829 	TAILQ_FOREACH(p, &t->table, link)
830 		if (func(p, arg) == 0)
831 			return (p);
832 	return (NULL);
833 }
834 
835 /*
836  * Register a transport
837  */
838 int
839 trans_register(const struct transport_def *def, struct transport **pp)
840 {
841 	u_int i;
842 	char or_descr[256];
843 
844 	if ((*pp = malloc(sizeof(**pp))) == NULL)
845 		return (SNMP_ERR_GENERR);
846 
847 	/* construct index */
848 	(*pp)->index.len = strlen(def->name) + 1;
849 	(*pp)->index.subs[0] = strlen(def->name);
850 	for (i = 0; i < (*pp)->index.subs[0]; i++)
851 		(*pp)->index.subs[i + 1] = def->name[i];
852 
853 	(*pp)->vtab = def;
854 
855 	if (FIND_OBJECT_OID(&transport_list, &(*pp)->index, 0) != NULL) {
856 		free(*pp);
857 		return (SNMP_ERR_INCONS_VALUE);
858 	}
859 
860 	/* register module */
861 	snprintf(or_descr, sizeof(or_descr), "%s transport mapping", def->name);
862 	if (((*pp)->or_index = or_register(&def->id, or_descr, NULL)) == 0) {
863 		free(*pp);
864 		return (SNMP_ERR_GENERR);
865 	}
866 
867 	INSERT_OBJECT_OID((*pp), &transport_list);
868 
869 	TAILQ_INIT(&(*pp)->table);
870 
871 	return (SNMP_ERR_NOERROR);
872 }
873 
874 /*
875  * Unregister transport
876  */
877 int
878 trans_unregister(struct transport *t)
879 {
880 	if (!TAILQ_EMPTY(&t->table))
881 		return (SNMP_ERR_INCONS_VALUE);
882 
883 	or_unregister(t->or_index);
884 	TAILQ_REMOVE(&transport_list, t, link);
885 
886 	return (SNMP_ERR_NOERROR);
887 }
888 
889 /*
890  * File descriptor support
891  */
892 #ifdef USE_LIBBEGEMOT
893 static void
894 input(int fd, int mask __unused, void *uap)
895 #else
896 static void
897 input(evContext ctx __unused, void *uap, int fd, int mask __unused)
898 #endif
899 {
900 	struct fdesc *f = uap;
901 
902 	(*f->func)(fd, f->udata);
903 }
904 
905 void
906 fd_suspend(void *p)
907 {
908 	struct fdesc *f = p;
909 
910 #ifdef USE_LIBBEGEMOT
911 	if (f->id >= 0) {
912 		poll_unregister(f->id);
913 		f->id = -1;
914 	}
915 #else
916 	if (evTestID(f->id)) {
917 		(void)evDeselectFD(evctx, f->id);
918 		evInitID(&f->id);
919 	}
920 #endif
921 }
922 
923 int
924 fd_resume(void *p)
925 {
926 	struct fdesc *f = p;
927 	int err;
928 
929 #ifdef USE_LIBBEGEMOT
930 	if (f->id >= 0)
931 		return (0);
932 	if ((f->id = poll_register(f->fd, input, f, POLL_IN)) < 0) {
933 		err = errno;
934 		syslog(LOG_ERR, "select fd %d: %m", f->fd);
935 		errno = err;
936 		return (-1);
937 	}
938 #else
939 	if (evTestID(f->id))
940 		return (0);
941 	if (evSelectFD(evctx, f->fd, EV_READ, input, f, &f->id)) {
942 		err = errno;
943 		syslog(LOG_ERR, "select fd %d: %m", f->fd);
944 		errno = err;
945 		return (-1);
946 	}
947 #endif
948 	return (0);
949 }
950 
951 void *
952 fd_select(int fd, void (*func)(int, void *), void *udata, struct lmodule *mod)
953 {
954 	struct fdesc *f;
955 	int err;
956 
957 	if ((f = malloc(sizeof(struct fdesc))) == NULL) {
958 		err = errno;
959 		syslog(LOG_ERR, "fd_select: %m");
960 		errno = err;
961 		return (NULL);
962 	}
963 	f->fd = fd;
964 	f->func = func;
965 	f->udata = udata;
966 	f->owner = mod;
967 #ifdef USE_LIBBEGEMOT
968 	f->id = -1;
969 #else
970 	evInitID(&f->id);
971 #endif
972 
973 	if (fd_resume(f)) {
974 		err = errno;
975 		free(f);
976 		errno = err;
977 		return (NULL);
978 	}
979 
980 	LIST_INSERT_HEAD(&fdesc_list, f, link);
981 
982 	return (f);
983 }
984 
985 void
986 fd_deselect(void *p)
987 {
988 	struct fdesc *f = p;
989 
990 	LIST_REMOVE(f, link);
991 	fd_suspend(f);
992 	free(f);
993 }
994 
995 static void
996 fd_flush(struct lmodule *mod)
997 {
998 	struct fdesc *t, *t1;
999 
1000 	t = LIST_FIRST(&fdesc_list);
1001 	while (t != NULL) {
1002 		t1 = LIST_NEXT(t, link);
1003 		if (t->owner == mod)
1004 			fd_deselect(t);
1005 		t = t1;
1006 	}
1007 }
1008 
1009 /*
1010  * Consume a message from the input buffer
1011  */
1012 static void
1013 snmp_input_consume(struct port_input *pi)
1014 {
1015 	if (!pi->stream) {
1016 		/* always consume everything */
1017 		pi->length = 0;
1018 		return;
1019 	}
1020 	if (pi->consumed >= pi->length) {
1021 		/* all bytes consumed */
1022 		pi->length = 0;
1023 		return;
1024 	}
1025 	memmove(pi->buf, pi->buf + pi->consumed, pi->length - pi->consumed);
1026 	pi->length -= pi->consumed;
1027 }
1028 
1029 struct credmsg {
1030 	struct cmsghdr hdr;
1031 	struct cmsgcred cred;
1032 };
1033 
1034 static void
1035 check_priv(struct port_input *pi, struct msghdr *msg)
1036 {
1037 	struct credmsg *cmsg;
1038 	struct xucred ucred;
1039 	socklen_t ucredlen;
1040 
1041 	pi->priv = 0;
1042 
1043 	if (msg->msg_controllen == sizeof(*cmsg)) {
1044 		/* process explicitly sends credentials */
1045 
1046 		cmsg = (struct credmsg *)msg->msg_control;
1047 		pi->priv = (cmsg->cred.cmcred_euid == 0);
1048 		return;
1049 	}
1050 
1051 	/* ok, obtain the accept time credentials */
1052 	ucredlen = sizeof(ucred);
1053 
1054 	if (getsockopt(pi->fd, 0, LOCAL_PEERCRED, &ucred, &ucredlen) == 0 &&
1055 	    ucredlen >= sizeof(ucred) && ucred.cr_version == XUCRED_VERSION)
1056 		pi->priv = (ucred.cr_uid == 0);
1057 }
1058 
1059 /*
1060  * Input from a stream socket.
1061  */
1062 static int
1063 recv_stream(struct port_input *pi)
1064 {
1065 	struct msghdr msg;
1066 	struct iovec iov[1];
1067 	ssize_t len;
1068 	struct credmsg cmsg;
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 	if (pi->cred) {
1088 		msg.msg_control = &cmsg;
1089 		msg.msg_controllen = sizeof(cmsg);
1090 
1091 		cmsg.hdr.cmsg_len = sizeof(cmsg);
1092 		cmsg.hdr.cmsg_level = SOL_SOCKET;
1093 		cmsg.hdr.cmsg_type = SCM_CREDS;
1094 	} else {
1095 		msg.msg_control = NULL;
1096 		msg.msg_controllen = 0;
1097 	}
1098 	msg.msg_flags = 0;
1099 
1100 	iov[0].iov_base = pi->buf + pi->length;
1101 	iov[0].iov_len = pi->buflen - pi->length;
1102 
1103 	len = recvmsg(pi->fd, &msg, 0);
1104 
1105 	if (len == -1 || len == 0)
1106 		/* receive error */
1107 		return (-1);
1108 
1109 	pi->length += len;
1110 
1111 	if (pi->cred)
1112 		check_priv(pi, &msg);
1113 
1114 	return (0);
1115 }
1116 
1117 /*
1118  * Input from a datagram socket.
1119  * Each receive should return one datagram.
1120  */
1121 static int
1122 recv_dgram(struct port_input *pi)
1123 {
1124 	u_char embuf[1000];
1125 	struct msghdr msg;
1126 	struct iovec iov[1];
1127 	ssize_t len;
1128 	struct credmsg cmsg;
1129 
1130 	if (pi->buf == NULL) {
1131 		/* no buffer yet - allocate one */
1132 		if ((pi->buf = buf_alloc(0)) == NULL) {
1133 			/* ups - could not get buffer. Read away input
1134 			 * and drop it */
1135 			(void)recvfrom(pi->fd, embuf, sizeof(embuf),
1136 			    0, NULL, NULL);
1137 			/* return error */
1138 			return (-1);
1139 		}
1140 		pi->buflen = buf_size(0);
1141 	}
1142 
1143 	/* try to get a message */
1144 	msg.msg_name = pi->peer;
1145 	msg.msg_namelen = pi->peerlen;
1146 	msg.msg_iov = iov;
1147 	msg.msg_iovlen = 1;
1148 	if (pi->cred) {
1149 		msg.msg_control = &cmsg;
1150 		msg.msg_controllen = sizeof(cmsg);
1151 
1152 		cmsg.hdr.cmsg_len = sizeof(cmsg);
1153 		cmsg.hdr.cmsg_level = SOL_SOCKET;
1154 		cmsg.hdr.cmsg_type = SCM_CREDS;
1155 	} else {
1156 		msg.msg_control = NULL;
1157 		msg.msg_controllen = 0;
1158 	}
1159 	msg.msg_flags = 0;
1160 
1161 	iov[0].iov_base = pi->buf;
1162 	iov[0].iov_len = pi->buflen;
1163 
1164 	len = recvmsg(pi->fd, &msg, 0);
1165 
1166 	if (len == -1 || len == 0)
1167 		/* receive error */
1168 		return (-1);
1169 
1170 	if (msg.msg_flags & MSG_TRUNC) {
1171 		/* truncated - drop */
1172 		snmpd_stats.silentDrops++;
1173 		snmpd_stats.inTooLong++;
1174 		return (-1);
1175 	}
1176 
1177 	pi->length = (size_t)len;
1178 
1179 	if (pi->cred)
1180 		check_priv(pi, &msg);
1181 
1182 	return (0);
1183 }
1184 
1185 /*
1186  * Input from a socket
1187  */
1188 int
1189 snmpd_input(struct port_input *pi, struct tport *tport)
1190 {
1191 	u_char *sndbuf;
1192 	size_t sndlen;
1193 	struct snmp_pdu pdu;
1194 	enum snmpd_input_err ierr, ferr;
1195 	enum snmpd_proxy_err perr;
1196 	int32_t vi;
1197 	int ret;
1198 	ssize_t slen;
1199 #ifdef USE_TCPWRAPPERS
1200 	char client[16];
1201 #endif
1202 
1203 	/* get input depending on the transport */
1204 	if (pi->stream) {
1205 		ret = recv_stream(pi);
1206 	} else {
1207 		ret = recv_dgram(pi);
1208 	}
1209 
1210 	if (ret == -1)
1211 		return (-1);
1212 
1213 #ifdef USE_TCPWRAPPERS
1214 	/*
1215 	 * In case of AF_INET{6} peer, do hosts_access(5) check.
1216 	 */
1217 	if (inet_ntop(pi->peer->sa_family,
1218 	    &((const struct sockaddr_in *)(const void *)pi->peer)->sin_addr,
1219 	    client, sizeof(client)) != NULL) {
1220 		request_set(&req, RQ_CLIENT_ADDR, client, 0);
1221 		if (hosts_access(&req) == 0) {
1222 			syslog(LOG_ERR, "refused connection from %.500s",
1223 			    eval_client(&req));
1224 			return (-1);
1225 		}
1226 	} else
1227 		syslog(LOG_ERR, "inet_ntop(): %m");
1228 #endif
1229 
1230 	/*
1231 	 * Handle input
1232 	 */
1233 	ierr = snmp_input_start(pi->buf, pi->length, "SNMP", &pdu, &vi,
1234 	    &pi->consumed);
1235 	if (ierr == SNMPD_INPUT_TRUNC) {
1236 		/* need more bytes. This is ok only for streaming transports.
1237 		 * but only if we have not reached bufsiz yet. */
1238 		if (pi->stream) {
1239 			if (pi->length == buf_size(0)) {
1240 				snmpd_stats.silentDrops++;
1241 				return (-1);
1242 			}
1243 			return (0);
1244 		}
1245 		snmpd_stats.silentDrops++;
1246 		return (-1);
1247 	}
1248 
1249 	/* can't check for bad SET pdus here, because a proxy may have to
1250 	 * check the access first. We don't want to return an error response
1251 	 * to a proxy PDU with a wrong community */
1252 	if (ierr == SNMPD_INPUT_FAILED) {
1253 		/* for streaming transports this is fatal */
1254 		if (pi->stream)
1255 			return (-1);
1256 		snmp_input_consume(pi);
1257 		return (0);
1258 	}
1259 	if (ierr == SNMPD_INPUT_BAD_COMM) {
1260 		snmp_input_consume(pi);
1261 		return (0);
1262 	}
1263 
1264 	/*
1265 	 * If that is a module community and the module has a proxy function,
1266 	 * the hand it over to the module.
1267 	 */
1268 	if (comm != NULL && comm->owner != NULL &&
1269 	    comm->owner->config->proxy != NULL) {
1270 		perr = (*comm->owner->config->proxy)(&pdu, tport->transport,
1271 		    &tport->index, pi->peer, pi->peerlen, ierr, vi,
1272 		    !pi->cred || pi->priv);
1273 
1274 		switch (perr) {
1275 
1276 		  case SNMPD_PROXY_OK:
1277 			snmp_input_consume(pi);
1278 			return (0);
1279 
1280 		  case SNMPD_PROXY_REJ:
1281 			break;
1282 
1283 		  case SNMPD_PROXY_DROP:
1284 			snmp_input_consume(pi);
1285 			snmp_pdu_free(&pdu);
1286 			snmpd_stats.proxyDrops++;
1287 			return (0);
1288 
1289 		  case SNMPD_PROXY_BADCOMM:
1290 			snmp_input_consume(pi);
1291 			snmp_pdu_free(&pdu);
1292 			snmpd_stats.inBadCommunityNames++;
1293 			if (snmpd.auth_traps)
1294 				snmp_send_trap(&oid_authenticationFailure,
1295 				    (struct snmp_value *)NULL);
1296 			return (0);
1297 
1298 		  case SNMPD_PROXY_BADCOMMUSE:
1299 			snmp_input_consume(pi);
1300 			snmp_pdu_free(&pdu);
1301 			snmpd_stats.inBadCommunityUses++;
1302 			if (snmpd.auth_traps)
1303 				snmp_send_trap(&oid_authenticationFailure,
1304 				    (struct snmp_value *)NULL);
1305 			return (0);
1306 		}
1307 	}
1308 
1309 	/*
1310 	 * Check type
1311 	 */
1312 	if (pdu.type == SNMP_PDU_RESPONSE ||
1313 	    pdu.type == SNMP_PDU_TRAP ||
1314 	    pdu.type == SNMP_PDU_TRAP2) {
1315 		snmpd_stats.silentDrops++;
1316 		snmpd_stats.inBadPduTypes++;
1317 		snmp_pdu_free(&pdu);
1318 		snmp_input_consume(pi);
1319 		return (0);
1320 	}
1321 
1322 	/*
1323 	 * Check community
1324 	 */
1325 	if (pdu.version < SNMP_V3 &&
1326 	    ((pi->cred && !pi->priv && pdu.type == SNMP_PDU_SET) ||
1327 	    (community != COMM_WRITE &&
1328             (pdu.type == SNMP_PDU_SET || community != COMM_READ)))) {
1329 		snmpd_stats.inBadCommunityUses++;
1330 		snmp_pdu_free(&pdu);
1331 		snmp_input_consume(pi);
1332 		if (snmpd.auth_traps)
1333 			snmp_send_trap(&oid_authenticationFailure,
1334 			    (struct snmp_value *)NULL);
1335 		return (0);
1336 	}
1337 
1338 	/*
1339 	 * Execute it.
1340 	 */
1341 	if ((sndbuf = buf_alloc(1)) == NULL) {
1342 		snmpd_stats.silentDrops++;
1343 		snmp_pdu_free(&pdu);
1344 		snmp_input_consume(pi);
1345 		return (0);
1346 	}
1347 	ferr = snmp_input_finish(&pdu, pi->buf, pi->length,
1348 	    sndbuf, &sndlen, "SNMP", ierr, vi, NULL);
1349 
1350 	if (ferr == SNMPD_INPUT_OK) {
1351 		slen = sendto(pi->fd, sndbuf, sndlen, 0, pi->peer, pi->peerlen);
1352 		if (slen == -1)
1353 			syslog(LOG_ERR, "sendto: %m");
1354 		else if ((size_t)slen != sndlen)
1355 			syslog(LOG_ERR, "sendto: short write %zu/%zu",
1356 			    sndlen, (size_t)slen);
1357 	}
1358 	snmp_pdu_free(&pdu);
1359 	free(sndbuf);
1360 	snmp_input_consume(pi);
1361 
1362 	return (0);
1363 }
1364 
1365 /*
1366  * Send a PDU to a given port
1367  */
1368 void
1369 snmp_send_port(void *targ, const struct asn_oid *port, struct snmp_pdu *pdu,
1370     const struct sockaddr *addr, socklen_t addrlen)
1371 {
1372 	struct transport *trans = targ;
1373 	struct tport *tp;
1374 	u_char *sndbuf;
1375 	size_t sndlen;
1376 	ssize_t len;
1377 
1378 	TAILQ_FOREACH(tp, &trans->table, link)
1379 		if (asn_compare_oid(port, &tp->index) == 0)
1380 			break;
1381 	if (tp == 0)
1382 		return;
1383 
1384 	if ((sndbuf = buf_alloc(1)) == NULL)
1385 		return;
1386 
1387 	snmp_output(pdu, sndbuf, &sndlen, "SNMP PROXY");
1388 
1389 	len = trans->vtab->send(tp, sndbuf, sndlen, addr, addrlen);
1390 
1391 	if (len == -1)
1392 		syslog(LOG_ERR, "sendto: %m");
1393 	else if ((size_t)len != sndlen)
1394 		syslog(LOG_ERR, "sendto: short write %zu/%zu",
1395 		    sndlen, (size_t)len);
1396 
1397 	free(sndbuf);
1398 }
1399 
1400 
1401 /*
1402  * Close an input source
1403  */
1404 void
1405 snmpd_input_close(struct port_input *pi)
1406 {
1407 	if (pi->id != NULL)
1408 		fd_deselect(pi->id);
1409 	if (pi->fd >= 0)
1410 		(void)close(pi->fd);
1411 	if (pi->buf != NULL)
1412 		free(pi->buf);
1413 }
1414 
1415 /*
1416  * Dump internal state.
1417  */
1418 #ifdef USE_LIBBEGEMOT
1419 static void
1420 info_func(void)
1421 #else
1422 static void
1423 info_func(evContext ctx __unused, void *uap __unused, const void *tag __unused)
1424 #endif
1425 {
1426 	struct lmodule *m;
1427 	u_int i;
1428 	char buf[10000];
1429 
1430 	syslog(LOG_DEBUG, "Dump of SNMPd %lu\n", (u_long)getpid());
1431 	for (i = 0; i < tree_size; i++) {
1432 		switch (tree[i].type) {
1433 
1434 		  case SNMP_NODE_LEAF:
1435 			sprintf(buf, "LEAF: %s %s", tree[i].name,
1436 			    asn_oid2str(&tree[i].oid));
1437 			break;
1438 
1439 		  case SNMP_NODE_COLUMN:
1440 			sprintf(buf, "COL: %s %s", tree[i].name,
1441 			    asn_oid2str(&tree[i].oid));
1442 			break;
1443 		}
1444 		syslog(LOG_DEBUG, "%s", buf);
1445 	}
1446 
1447 	TAILQ_FOREACH(m, &lmodules, link)
1448 		if (m->config->dump)
1449 			(*m->config->dump)();
1450 }
1451 
1452 /*
1453  * Re-read configuration
1454  */
1455 #ifdef USE_LIBBEGEMOT
1456 static void
1457 config_func(void)
1458 #else
1459 static void
1460 config_func(evContext ctx __unused, void *uap __unused,
1461     const void *tag __unused)
1462 #endif
1463 {
1464 	struct lmodule *m;
1465 
1466 	if (read_config(config_file, NULL)) {
1467 		syslog(LOG_ERR, "error reading config file '%s'", config_file);
1468 		return;
1469 	}
1470 	TAILQ_FOREACH(m, &lmodules, link)
1471 		if (m->config->config)
1472 			(*m->config->config)();
1473 }
1474 
1475 /*
1476  * On USR1 dump actual configuration.
1477  */
1478 static void
1479 onusr1(int s __unused)
1480 {
1481 
1482 	work |= WORK_DOINFO;
1483 }
1484 static void
1485 onhup(int s __unused)
1486 {
1487 
1488 	work |= WORK_RECONFIG;
1489 }
1490 
1491 static void
1492 onterm(int s __unused)
1493 {
1494 
1495 	/* allow clean-up */
1496 	exit(0);
1497 }
1498 
1499 static void
1500 init_sigs(void)
1501 {
1502 	struct sigaction sa;
1503 
1504 	sa.sa_handler = onusr1;
1505 	sa.sa_flags = SA_RESTART;
1506 	sigemptyset(&sa.sa_mask);
1507 	if (sigaction(SIGUSR1, &sa, NULL)) {
1508 		syslog(LOG_ERR, "sigaction: %m");
1509 		exit(1);
1510 	}
1511 
1512 	sa.sa_handler = onhup;
1513 	if (sigaction(SIGHUP, &sa, NULL)) {
1514 		syslog(LOG_ERR, "sigaction: %m");
1515 		exit(1);
1516 	}
1517 
1518 	sa.sa_handler = onterm;
1519 	sa.sa_flags = 0;
1520 	sigemptyset(&sa.sa_mask);
1521 	if (sigaction(SIGTERM, &sa, NULL)) {
1522 		syslog(LOG_ERR, "sigaction: %m");
1523 		exit(1);
1524 	}
1525 	if (sigaction(SIGINT, &sa, NULL)) {
1526 		syslog(LOG_ERR, "sigaction: %m");
1527 		exit(1);
1528 	}
1529 }
1530 
1531 static void
1532 block_sigs(void)
1533 {
1534 	sigset_t set;
1535 
1536 	sigfillset(&set);
1537 	if (sigprocmask(SIG_BLOCK, &set, &blocked_sigs) == -1) {
1538 		syslog(LOG_ERR, "SIG_BLOCK: %m");
1539 		exit(1);
1540 	}
1541 }
1542 static void
1543 unblock_sigs(void)
1544 {
1545 	if (sigprocmask(SIG_SETMASK, &blocked_sigs, NULL) == -1) {
1546 		syslog(LOG_ERR, "SIG_SETMASK: %m");
1547 		exit(1);
1548 	}
1549 }
1550 
1551 /*
1552  * Shut down
1553  */
1554 static void
1555 term(void)
1556 {
1557 	(void)unlink(pid_file);
1558 }
1559 
1560 static void
1561 trans_stop(void)
1562 {
1563 	struct transport *t;
1564 
1565 	TAILQ_FOREACH(t, &transport_list, link)
1566 		(void)t->vtab->stop(1);
1567 }
1568 
1569 /*
1570  * Define a macro from the command line
1571  */
1572 static void
1573 do_macro(char *arg)
1574 {
1575 	char *eq;
1576 	int err;
1577 
1578 	if ((eq = strchr(arg, '=')) == NULL)
1579 		err = define_macro(arg, "");
1580 	else {
1581 		*eq++ = '\0';
1582 		err = define_macro(arg, eq);
1583 	}
1584 	if (err == -1) {
1585 		syslog(LOG_ERR, "cannot save macro: %m");
1586 		exit(1);
1587 	}
1588 }
1589 
1590 /*
1591  * Re-implement getsubopt from scratch, because the second argument is broken
1592  * and will not compile with WARNS=5.
1593  */
1594 static int
1595 getsubopt1(char **arg, const char *const *options, char **valp, char **optp)
1596 {
1597 	static const char *const delim = ",\t ";
1598 	u_int i;
1599 	char *ptr;
1600 
1601 	*optp = NULL;
1602 
1603 	/* skip leading junk */
1604 	for (ptr = *arg; *ptr != '\0'; ptr++)
1605 		if (strchr(delim, *ptr) == NULL)
1606 			break;
1607 	if (*ptr == '\0') {
1608 		*arg = ptr;
1609 		return (-1);
1610 	}
1611 	*optp = ptr;
1612 
1613 	/* find the end of the option */
1614 	while (*++ptr != '\0')
1615 		if (strchr(delim, *ptr) != NULL || *ptr == '=')
1616 			break;
1617 
1618 	if (*ptr != '\0') {
1619 		if (*ptr == '=') {
1620 			*ptr++ = '\0';
1621 			*valp = ptr;
1622 			while (*ptr != '\0' && strchr(delim, *ptr) == NULL)
1623 				ptr++;
1624 			if (*ptr != '\0')
1625 				*ptr++ = '\0';
1626 		} else
1627 			*ptr++ = '\0';
1628 	}
1629 
1630 	*arg = ptr;
1631 
1632 	for (i = 0; *options != NULL; options++, i++)
1633 		if (strcmp(*optp, *options) == 0)
1634 			return (i);
1635 	return (-1);
1636 }
1637 
1638 int
1639 main(int argc, char *argv[])
1640 {
1641 	int opt;
1642 	FILE *fp;
1643 	int background = 1;
1644 	struct tport *p;
1645 	const char *prefix = "snmpd";
1646 	struct lmodule *m;
1647 	char *value = NULL, *option; /* XXX */
1648 	struct transport *t;
1649 
1650 #define DBG_DUMP	0
1651 #define DBG_EVENTS	1
1652 #define DBG_TRACE	2
1653 	static const char *const debug_opts[] = {
1654 		"dump",
1655 		"events",
1656 		"trace",
1657 		NULL
1658 	};
1659 
1660 	snmp_printf = snmp_printf_func;
1661 	snmp_error = snmp_error_func;
1662 	snmp_debug = snmp_debug_func;
1663 	asn_error = asn_error_func;
1664 
1665 	while ((opt = getopt(argc, argv, "c:dD:e:hI:l:m:p:")) != EOF)
1666 		switch (opt) {
1667 
1668 		  case 'c':
1669 			strlcpy(config_file, optarg, sizeof(config_file));
1670 			break;
1671 
1672 		  case 'd':
1673 			background = 0;
1674 			break;
1675 
1676 		  case 'D':
1677 			while (*optarg) {
1678 				switch (getsubopt1(&optarg, debug_opts,
1679 				    &value, &option)) {
1680 
1681 				  case DBG_DUMP:
1682 					debug.dump_pdus = 1;
1683 					break;
1684 
1685 				  case DBG_EVENTS:
1686 					debug.evdebug++;
1687 					break;
1688 
1689 				  case DBG_TRACE:
1690 					if (value == NULL)
1691 						syslog(LOG_ERR,
1692 						    "no value for 'trace'");
1693 					else
1694 						snmp_trace = strtoul(value,
1695 						    NULL, 0);
1696 					break;
1697 
1698 				  case -1:
1699 					if (suboptarg)
1700 						syslog(LOG_ERR,
1701 						    "unknown debug flag '%s'",
1702 						    option);
1703 					else
1704 						syslog(LOG_ERR,
1705 						    "missing debug flag");
1706 					break;
1707 				}
1708 			}
1709 			break;
1710 
1711 		  case 'e':
1712 			strlcpy(engine_file, optarg, sizeof(engine_file));
1713 			break;
1714 		  case 'h':
1715 			fprintf(stderr, "%s", usgtxt);
1716 			exit(0);
1717 
1718 		  case 'I':
1719 			syspath = optarg;
1720 			break;
1721 
1722 		  case 'l':
1723 			prefix = optarg;
1724 			break;
1725 
1726 		  case 'm':
1727 			do_macro(optarg);
1728 			break;
1729 
1730 		  case 'p':
1731 			strlcpy(pid_file, optarg, sizeof(pid_file));
1732 			break;
1733 		}
1734 
1735 	openlog(prefix, LOG_PID | (background ? 0 : LOG_PERROR), LOG_USER);
1736 	setlogmask(LOG_UPTO(debug.logpri - 1));
1737 
1738 	if (background && daemon(0, 0) < 0) {
1739 		syslog(LOG_ERR, "daemon: %m");
1740 		exit(1);
1741 	}
1742 
1743 	argc -= optind;
1744 	argv += optind;
1745 
1746 	progargs = argv;
1747 	nprogargs = argc;
1748 
1749 	srandomdev();
1750 
1751 	snmp_serial_no = random();
1752 
1753 #ifdef USE_TCPWRAPPERS
1754 	/*
1755 	 * Initialize hosts_access(3) handler.
1756 	 */
1757 	request_init(&req, RQ_DAEMON, "snmpd", 0);
1758 	sock_methods(&req);
1759 #endif
1760 
1761 	/*
1762 	 * Initialize the tree.
1763 	 */
1764 	if ((tree = malloc(sizeof(struct snmp_node) * CTREE_SIZE)) == NULL) {
1765 		syslog(LOG_ERR, "%m");
1766 		exit(1);
1767 	}
1768 	memcpy(tree, ctree, sizeof(struct snmp_node) * CTREE_SIZE);
1769 	tree_size = CTREE_SIZE;
1770 
1771 	/*
1772 	 * Get standard communities
1773 	 */
1774 	(void)comm_define(1, "SNMP read", NULL, NULL);
1775 	(void)comm_define(2, "SNMP write", NULL, NULL);
1776 	community = COMM_INITIALIZE;
1777 
1778 	trap_reqid = reqid_allocate(512, NULL);
1779 
1780 	if (config_file[0] == '\0')
1781 		snprintf(config_file, sizeof(config_file), PATH_CONFIG, prefix);
1782 
1783 	init_actvals();
1784 	init_snmpd_engine();
1785 
1786 	this_tick = get_ticks();
1787 	start_tick = this_tick;
1788 
1789 	/* start transports */
1790 	if (atexit(trans_stop) == -1) {
1791 		syslog(LOG_ERR, "atexit failed: %m");
1792 		exit(1);
1793 	}
1794 	if (udp_trans.start() != SNMP_ERR_NOERROR)
1795 		syslog(LOG_WARNING, "cannot start UDP transport");
1796 	if (lsock_trans.start() != SNMP_ERR_NOERROR)
1797 		syslog(LOG_WARNING, "cannot start LSOCK transport");
1798 
1799 #ifdef USE_LIBBEGEMOT
1800 	if (debug.evdebug > 0)
1801 		rpoll_trace = 1;
1802 #else
1803 	if (evCreate(&evctx)) {
1804 		syslog(LOG_ERR, "evCreate: %m");
1805 		exit(1);
1806 	}
1807 	if (debug.evdebug > 0)
1808 		evSetDebug(evctx, 10, stderr);
1809 #endif
1810 
1811 	if (engine_file[0] == '\0')
1812 		snprintf(engine_file, sizeof(engine_file), PATH_ENGINE, prefix);
1813 
1814 	if (read_config(config_file, NULL)) {
1815 		syslog(LOG_ERR, "error in config file");
1816 		exit(1);
1817 	}
1818 
1819 	TAILQ_FOREACH(t, &transport_list, link)
1820 		TAILQ_FOREACH(p, &t->table, link)
1821 			t->vtab->init_port(p);
1822 
1823 	init_sigs();
1824 
1825 	if (pid_file[0] == '\0')
1826 		snprintf(pid_file, sizeof(pid_file), PATH_PID, prefix);
1827 
1828 	if ((fp = fopen(pid_file, "w")) != NULL) {
1829 		fprintf(fp, "%u", getpid());
1830 		fclose(fp);
1831 		if (atexit(term) == -1) {
1832 			syslog(LOG_ERR, "atexit failed: %m");
1833 			(void)remove(pid_file);
1834 			exit(0);
1835 		}
1836 	}
1837 
1838 	if (or_register(&oid_snmpMIB, "The MIB module for SNMPv2 entities.",
1839 	    NULL) == 0) {
1840 		syslog(LOG_ERR, "cannot register SNMPv2 MIB");
1841 		exit(1);
1842 	}
1843 	if (or_register(&oid_begemotSnmpd, "The MIB module for the Begemot SNMPd.",
1844 	    NULL) == 0) {
1845 		syslog(LOG_ERR, "cannot register begemotSnmpd MIB");
1846 		exit(1);
1847 	}
1848 
1849 	while ((m = TAILQ_FIRST(&modules_start)) != NULL) {
1850 		m->flags &= ~LM_ONSTARTLIST;
1851 		TAILQ_REMOVE(&modules_start, m, start);
1852 		lm_start(m);
1853 	}
1854 
1855 	snmp_send_trap(&oid_coldStart, (struct snmp_value *)NULL);
1856 
1857 	for (;;) {
1858 #ifndef USE_LIBBEGEMOT
1859 		evEvent event;
1860 #endif
1861 		struct lmodule *mod;
1862 
1863 		TAILQ_FOREACH(mod, &lmodules, link)
1864 			if (mod->config->idle != NULL)
1865 				(*mod->config->idle)();
1866 
1867 #ifndef USE_LIBBEGEMOT
1868 		if (evGetNext(evctx, &event, EV_WAIT) == 0) {
1869 			if (evDispatch(evctx, event))
1870 				syslog(LOG_ERR, "evDispatch: %m");
1871 		} else if (errno != EINTR) {
1872 			syslog(LOG_ERR, "evGetNext: %m");
1873 			exit(1);
1874 		}
1875 #else
1876 		poll_dispatch(1);
1877 #endif
1878 
1879 		if (work != 0) {
1880 			block_sigs();
1881 			if (work & WORK_DOINFO) {
1882 #ifdef USE_LIBBEGEMOT
1883 				info_func();
1884 #else
1885 				if (evWaitFor(evctx, &work, info_func,
1886 				    NULL, NULL) == -1) {
1887 					syslog(LOG_ERR, "evWaitFor: %m");
1888 					exit(1);
1889 				}
1890 #endif
1891 			}
1892 			if (work & WORK_RECONFIG) {
1893 #ifdef USE_LIBBEGEMOT
1894 				config_func();
1895 #else
1896 				if (evWaitFor(evctx, &work, config_func,
1897 				    NULL, NULL) == -1) {
1898 					syslog(LOG_ERR, "evWaitFor: %m");
1899 					exit(1);
1900 				}
1901 #endif
1902 			}
1903 			work = 0;
1904 			unblock_sigs();
1905 #ifndef USE_LIBBEGEMOT
1906 			if (evDo(evctx, &work) == -1) {
1907 				syslog(LOG_ERR, "evDo: %m");
1908 				exit(1);
1909 			}
1910 #endif
1911 		}
1912 	}
1913 
1914 	return (0);
1915 }
1916 
1917 uint64_t
1918 get_ticks(void)
1919 {
1920 	struct timeval tv;
1921 	uint64_t ret;
1922 
1923 	if (gettimeofday(&tv, NULL))
1924 		abort();
1925 	ret = tv.tv_sec * 100ULL + tv.tv_usec / 10000ULL;
1926 	return (ret);
1927 }
1928 
1929 /*
1930  * Timer support
1931  */
1932 
1933 /*
1934  * Trampoline for the non-repeatable timers.
1935  */
1936 #ifdef USE_LIBBEGEMOT
1937 static void
1938 tfunc(int tid __unused, void *uap)
1939 #else
1940 static void
1941 tfunc(evContext ctx __unused, void *uap, struct timespec due __unused,
1942 	struct timespec inter __unused)
1943 #endif
1944 {
1945 	struct timer *tp = uap;
1946 
1947 	LIST_REMOVE(tp, link);
1948 	tp->func(tp->udata);
1949 	free(tp);
1950 }
1951 
1952 /*
1953  * Trampoline for the repeatable timers.
1954  */
1955 #ifdef USE_LIBBEGEMOT
1956 static void
1957 trfunc(int tid __unused, void *uap)
1958 #else
1959 static void
1960 trfunc(evContext ctx __unused, void *uap, struct timespec due __unused,
1961 	struct timespec inter __unused)
1962 #endif
1963 {
1964 	struct timer *tp = uap;
1965 
1966 	tp->func(tp->udata);
1967 }
1968 
1969 /*
1970  * Start a one-shot timer
1971  */
1972 void *
1973 timer_start(u_int ticks, void (*func)(void *), void *udata, struct lmodule *mod)
1974 {
1975 	struct timer *tp;
1976 #ifndef USE_LIBBEGEMOT
1977 	struct timespec due;
1978 #endif
1979 
1980 	if ((tp = malloc(sizeof(struct timer))) == NULL) {
1981 		syslog(LOG_CRIT, "out of memory for timer");
1982 		exit(1);
1983 	}
1984 
1985 #ifndef USE_LIBBEGEMOT
1986 	due = evAddTime(evNowTime(),
1987 	    evConsTime(ticks / 100, (ticks % 100) * 10000));
1988 #endif
1989 
1990 	tp->udata = udata;
1991 	tp->owner = mod;
1992 	tp->func = func;
1993 
1994 	LIST_INSERT_HEAD(&timer_list, tp, link);
1995 
1996 #ifdef USE_LIBBEGEMOT
1997 	if ((tp->id = poll_start_timer(ticks * 10, 0, tfunc, tp)) < 0) {
1998 		syslog(LOG_ERR, "cannot set timer: %m");
1999 		exit(1);
2000 	}
2001 #else
2002 	if (evSetTimer(evctx, tfunc, tp, due, evConsTime(0, 0), &tp->id)
2003 	    == -1) {
2004 		syslog(LOG_ERR, "cannot set timer: %m");
2005 		exit(1);
2006 	}
2007 #endif
2008 	return (tp);
2009 }
2010 
2011 /*
2012  * Start a repeatable timer. When used with USE_LIBBEGEMOT the first argument
2013  * is currently ignored and the initial number of ticks is set to the
2014  * repeat number of ticks.
2015  */
2016 void *
2017 timer_start_repeat(u_int ticks __unused, u_int repeat_ticks,
2018     void (*func)(void *), void *udata, struct lmodule *mod)
2019 {
2020 	struct timer *tp;
2021 #ifndef USE_LIBBEGEMOT
2022 	struct timespec due;
2023 	struct timespec inter;
2024 #endif
2025 
2026 	if ((tp = malloc(sizeof(struct timer))) == NULL) {
2027 		syslog(LOG_CRIT, "out of memory for timer");
2028 		exit(1);
2029 	}
2030 
2031 #ifndef USE_LIBBEGEMOT
2032 	due = evAddTime(evNowTime(),
2033 	    evConsTime(ticks / 100, (ticks % 100) * 10000));
2034 	inter = evConsTime(repeat_ticks / 100, (repeat_ticks % 100) * 10000);
2035 #endif
2036 
2037 	tp->udata = udata;
2038 	tp->owner = mod;
2039 	tp->func = func;
2040 
2041 	LIST_INSERT_HEAD(&timer_list, tp, link);
2042 
2043 #ifdef USE_LIBBEGEMOT
2044 	if ((tp->id = poll_start_timer(repeat_ticks * 10, 1, trfunc, tp)) < 0) {
2045 		syslog(LOG_ERR, "cannot set timer: %m");
2046 		exit(1);
2047 	}
2048 #else
2049 	if (evSetTimer(evctx, trfunc, tp, due, inter, &tp->id) == -1) {
2050 		syslog(LOG_ERR, "cannot set timer: %m");
2051 		exit(1);
2052 	}
2053 #endif
2054 	return (tp);
2055 }
2056 
2057 /*
2058  * Stop a timer.
2059  */
2060 void
2061 timer_stop(void *p)
2062 {
2063 	struct timer *tp = p;
2064 
2065 	LIST_REMOVE(tp, link);
2066 #ifdef USE_LIBBEGEMOT
2067 	poll_stop_timer(tp->id);
2068 #else
2069 	if (evClearTimer(evctx, tp->id) == -1) {
2070 		syslog(LOG_ERR, "cannot stop timer: %m");
2071 		exit(1);
2072 	}
2073 #endif
2074 	free(p);
2075 }
2076 
2077 static void
2078 timer_flush(struct lmodule *mod)
2079 {
2080 	struct timer *t, *t1;
2081 
2082 	t = LIST_FIRST(&timer_list);
2083 	while (t != NULL) {
2084 		t1 = LIST_NEXT(t, link);
2085 		if (t->owner == mod)
2086 			timer_stop(t);
2087 		t = t1;
2088 	}
2089 }
2090 
2091 static void
2092 snmp_printf_func(const char *fmt, ...)
2093 {
2094 	va_list ap;
2095 	static char *pend = NULL;
2096 	char *ret, *new;
2097 
2098 	va_start(ap, fmt);
2099 	vasprintf(&ret, fmt, ap);
2100 	va_end(ap);
2101 
2102 	if (ret == NULL)
2103 		return;
2104 	if (pend != NULL) {
2105 		if ((new = realloc(pend, strlen(pend) + strlen(ret) + 1))
2106 		    == NULL) {
2107 			free(ret);
2108 			return;
2109 		}
2110 		pend = new;
2111 		strcat(pend, ret);
2112 		free(ret);
2113 	} else
2114 		pend = ret;
2115 
2116 	while ((ret = strchr(pend, '\n')) != NULL) {
2117 		*ret = '\0';
2118 		syslog(LOG_DEBUG, "%s", pend);
2119 		if (strlen(ret + 1) == 0) {
2120 			free(pend);
2121 			pend = NULL;
2122 			break;
2123 		}
2124 		strcpy(pend, ret + 1);
2125 	}
2126 }
2127 
2128 static void
2129 snmp_error_func(const char *err, ...)
2130 {
2131 	char errbuf[1000];
2132 	va_list ap;
2133 
2134 	if (!(snmp_trace & LOG_SNMP_ERRORS))
2135 		return;
2136 
2137 	va_start(ap, err);
2138 	snprintf(errbuf, sizeof(errbuf), "SNMP: ");
2139 	vsnprintf(errbuf + strlen(errbuf),
2140 	    sizeof(errbuf) - strlen(errbuf), err, ap);
2141 	va_end(ap);
2142 
2143 	syslog(LOG_ERR, "%s", errbuf);
2144 }
2145 
2146 static void
2147 snmp_debug_func(const char *err, ...)
2148 {
2149 	char errbuf[1000];
2150 	va_list ap;
2151 
2152 	va_start(ap, err);
2153 	snprintf(errbuf, sizeof(errbuf), "SNMP: ");
2154 	vsnprintf(errbuf+strlen(errbuf), sizeof(errbuf)-strlen(errbuf),
2155 	    err, ap);
2156 	va_end(ap);
2157 
2158 	syslog(LOG_DEBUG, "%s", errbuf);
2159 }
2160 
2161 static void
2162 asn_error_func(const struct asn_buf *b, const char *err, ...)
2163 {
2164 	char errbuf[1000];
2165 	va_list ap;
2166 	u_int i;
2167 
2168 	if (!(snmp_trace & LOG_ASN1_ERRORS))
2169 		return;
2170 
2171 	va_start(ap, err);
2172 	snprintf(errbuf, sizeof(errbuf), "ASN.1: ");
2173 	vsnprintf(errbuf + strlen(errbuf),
2174 	    sizeof(errbuf) - strlen(errbuf), err, ap);
2175 	va_end(ap);
2176 
2177 	if (b != NULL) {
2178 		snprintf(errbuf + strlen(errbuf),
2179 		    sizeof(errbuf) - strlen(errbuf), " at");
2180 		for (i = 0; b->asn_len > i; i++)
2181 			snprintf(errbuf + strlen(errbuf),
2182 			    sizeof(errbuf) - strlen(errbuf),
2183 			    " %02x", b->asn_cptr[i]);
2184 	}
2185 
2186 	syslog(LOG_ERR, "%s", errbuf);
2187 }
2188 
2189 /*
2190  * Create a new community
2191  */
2192 u_int
2193 comm_define(u_int priv, const char *descr, struct lmodule *owner,
2194     const char *str)
2195 {
2196 	struct community *c, *p;
2197 	u_int ncomm;
2198 
2199 	/* generate an identifier */
2200 	do {
2201 		if ((ncomm = next_community_index++) == UINT_MAX)
2202 			next_community_index = 1;
2203 		TAILQ_FOREACH(c, &community_list, link)
2204 			if (c->value == ncomm)
2205 				break;
2206 	} while (c != NULL);
2207 
2208 	if ((c = malloc(sizeof(struct community))) == NULL) {
2209 		syslog(LOG_ERR, "comm_define: %m");
2210 		return (0);
2211 	}
2212 	c->owner = owner;
2213 	c->value = ncomm;
2214 	c->descr = descr;
2215 	c->string = NULL;
2216 	c->private = priv;
2217 
2218 	if (str != NULL) {
2219 		if((c->string = malloc(strlen(str)+1)) == NULL) {
2220 			free(c);
2221 			return (0);
2222 		}
2223 		strcpy(c->string, str);
2224 	}
2225 
2226 	/* make index */
2227 	if (c->owner == NULL) {
2228 		c->index.len = 1;
2229 		c->index.subs[0] = 0;
2230 	} else {
2231 		c->index = c->owner->index;
2232 	}
2233 	c->index.subs[c->index.len++] = c->private;
2234 
2235 	/*
2236 	 * Insert ordered
2237 	 */
2238 	TAILQ_FOREACH(p, &community_list, link) {
2239 		if (asn_compare_oid(&p->index, &c->index) > 0) {
2240 			TAILQ_INSERT_BEFORE(p, c, link);
2241 			break;
2242 		}
2243 	}
2244 	if (p == NULL)
2245 		TAILQ_INSERT_TAIL(&community_list, c, link);
2246 	return (c->value);
2247 }
2248 
2249 const char *
2250 comm_string(u_int ncomm)
2251 {
2252 	struct community *p;
2253 
2254 	TAILQ_FOREACH(p, &community_list, link)
2255 		if (p->value == ncomm)
2256 			return (p->string);
2257 	return (NULL);
2258 }
2259 
2260 /*
2261  * Delete all communities allocated by a module
2262  */
2263 static void
2264 comm_flush(struct lmodule *mod)
2265 {
2266 	struct community *p, *p1;
2267 
2268 	p = TAILQ_FIRST(&community_list);
2269 	while (p != NULL) {
2270 		p1 = TAILQ_NEXT(p, link);
2271 		if (p->owner == mod) {
2272 			free(p->string);
2273 			TAILQ_REMOVE(&community_list, p, link);
2274 			free(p);
2275 		}
2276 		p = p1;
2277 	}
2278 }
2279 
2280 /*
2281  * Request ID handling.
2282  *
2283  * Allocate a new range of request ids. Use a first fit algorithm.
2284  */
2285 u_int
2286 reqid_allocate(int size, struct lmodule *mod)
2287 {
2288 	u_int type;
2289 	struct idrange *r, *r1;
2290 
2291 	if (size <= 0 || size > INT32_MAX) {
2292 		syslog(LOG_CRIT, "%s: size out of range: %d", __func__, size);
2293 		return (0);
2294 	}
2295 	/* allocate a type id */
2296 	do {
2297 		if ((type = next_idrange++) == UINT_MAX)
2298 			next_idrange = 1;
2299 		TAILQ_FOREACH(r, &idrange_list, link)
2300 			if (r->type == type)
2301 				break;
2302 	} while(r != NULL);
2303 
2304 	/* find a range */
2305 	if (TAILQ_EMPTY(&idrange_list))
2306 		r = NULL;
2307 	else {
2308 		r = TAILQ_FIRST(&idrange_list);
2309 		if (r->base < size) {
2310 			while((r1 = TAILQ_NEXT(r, link)) != NULL) {
2311 				if (r1->base - (r->base + r->size) >= size)
2312 					break;
2313 				r = r1;
2314 			}
2315 			r = r1;
2316 		}
2317 		if (r == NULL) {
2318 			r1 = TAILQ_LAST(&idrange_list, idrange_list);
2319 			if (INT32_MAX - size + 1 < r1->base + r1->size) {
2320 				syslog(LOG_ERR, "out of id ranges (%u)", size);
2321 				return (0);
2322 			}
2323 		}
2324 	}
2325 
2326 	/* allocate structure */
2327 	if ((r1 = malloc(sizeof(struct idrange))) == NULL) {
2328 		syslog(LOG_ERR, "%s: %m", __FUNCTION__);
2329 		return (0);
2330 	}
2331 
2332 	r1->type = type;
2333 	r1->size = size;
2334 	r1->owner = mod;
2335 	if (TAILQ_EMPTY(&idrange_list) || r == TAILQ_FIRST(&idrange_list)) {
2336 		r1->base = 0;
2337 		TAILQ_INSERT_HEAD(&idrange_list, r1, link);
2338 	} else if (r == NULL) {
2339 		r = TAILQ_LAST(&idrange_list, idrange_list);
2340 		r1->base = r->base + r->size;
2341 		TAILQ_INSERT_TAIL(&idrange_list, r1, link);
2342 	} else {
2343 		r = TAILQ_PREV(r, idrange_list, link);
2344 		r1->base = r->base + r->size;
2345 		TAILQ_INSERT_AFTER(&idrange_list, r, r1, link);
2346 	}
2347 	r1->next = r1->base;
2348 
2349 	return (type);
2350 }
2351 
2352 int32_t
2353 reqid_next(u_int type)
2354 {
2355 	struct idrange *r;
2356 	int32_t id;
2357 
2358 	TAILQ_FOREACH(r, &idrange_list, link)
2359 		if (r->type == type)
2360 			break;
2361 	if (r == NULL) {
2362 		syslog(LOG_CRIT, "wrong idrange type");
2363 		abort();
2364 	}
2365 	if ((id = r->next++) == r->base + (r->size - 1))
2366 		r->next = r->base;
2367 	return (id);
2368 }
2369 
2370 int32_t
2371 reqid_base(u_int type)
2372 {
2373 	struct idrange *r;
2374 
2375 	TAILQ_FOREACH(r, &idrange_list, link)
2376 		if (r->type == type)
2377 			return (r->base);
2378 	syslog(LOG_CRIT, "wrong idrange type");
2379 	abort();
2380 }
2381 
2382 u_int
2383 reqid_type(int32_t reqid)
2384 {
2385 	struct idrange *r;
2386 
2387 	TAILQ_FOREACH(r, &idrange_list, link)
2388 		if (reqid >= r->base && reqid <= r->base + (r->size - 1))
2389 			return (r->type);
2390 	return (0);
2391 }
2392 
2393 int
2394 reqid_istype(int32_t reqid, u_int type)
2395 {
2396 	return (reqid_type(reqid) == type);
2397 }
2398 
2399 /*
2400  * Delete all communities allocated by a module
2401  */
2402 static void
2403 reqid_flush(struct lmodule *mod)
2404 {
2405 	struct idrange *p, *p1;
2406 
2407 	p = TAILQ_FIRST(&idrange_list);
2408 	while (p != NULL) {
2409 		p1 = TAILQ_NEXT(p, link);
2410 		if (p->owner == mod) {
2411 			TAILQ_REMOVE(&idrange_list, p, link);
2412 			free(p);
2413 		}
2414 		p = p1;
2415 	}
2416 }
2417 
2418 /*
2419  * Merge the given tree for the given module into the main tree.
2420  */
2421 static int
2422 compare_node(const void *v1, const void *v2)
2423 {
2424 	const struct snmp_node *n1 = v1;
2425 	const struct snmp_node *n2 = v2;
2426 
2427 	return (asn_compare_oid(&n1->oid, &n2->oid));
2428 }
2429 static int
2430 tree_merge(const struct snmp_node *ntree, u_int nsize, struct lmodule *mod)
2431 {
2432 	struct snmp_node *xtree;
2433 	u_int i;
2434 
2435 	xtree = realloc(tree, sizeof(*tree) * (tree_size + nsize));
2436 	if (xtree == NULL) {
2437 		syslog(LOG_ERR, "tree_merge: %m");
2438 		return (-1);
2439 	}
2440 	tree = xtree;
2441 	memcpy(&tree[tree_size], ntree, sizeof(*tree) * nsize);
2442 
2443 	for (i = 0; i < nsize; i++)
2444 		tree[tree_size + i].tree_data = mod;
2445 
2446 	tree_size += nsize;
2447 
2448 	qsort(tree, tree_size, sizeof(tree[0]), compare_node);
2449 
2450 	return (0);
2451 }
2452 
2453 /*
2454  * Remove all nodes belonging to the loadable module
2455  */
2456 static void
2457 tree_unmerge(struct lmodule *mod)
2458 {
2459 	u_int s, d;
2460 
2461 	for(s = d = 0; s < tree_size; s++)
2462 		if (tree[s].tree_data != mod) {
2463 			if (s != d)
2464 				tree[d] = tree[s];
2465 			d++;
2466 		}
2467 	tree_size = d;
2468 }
2469 
2470 /*
2471  * Loadable modules
2472  */
2473 struct lmodule *
2474 lm_load(const char *path, const char *section)
2475 {
2476 	struct lmodule *m;
2477 	int err;
2478 	int i;
2479 	char *av[MAX_MOD_ARGS + 1];
2480 	int ac;
2481 	u_int u;
2482 
2483 	if ((m = malloc(sizeof(*m))) == NULL) {
2484 		syslog(LOG_ERR, "lm_load: %m");
2485 		return (NULL);
2486 	}
2487 	m->handle = NULL;
2488 	m->flags = 0;
2489 	strcpy(m->section, section);
2490 
2491 	if ((m->path = malloc(strlen(path) + 1)) == NULL) {
2492 		syslog(LOG_ERR, "lm_load: %m");
2493 		goto err;
2494 	}
2495 	strcpy(m->path, path);
2496 
2497 	/*
2498 	 * Make index
2499 	 */
2500 	m->index.subs[0] = strlen(section);
2501 	m->index.len = m->index.subs[0] + 1;
2502 	for (u = 0; u < m->index.subs[0]; u++)
2503 		m->index.subs[u + 1] = section[u];
2504 
2505 	/*
2506 	 * Load the object file and locate the config structure
2507 	 */
2508 	if ((m->handle = dlopen(m->path, RTLD_NOW|RTLD_GLOBAL)) == NULL) {
2509 		syslog(LOG_ERR, "lm_load: open %s", dlerror());
2510 		goto err;
2511 	}
2512 
2513 	if ((m->config = dlsym(m->handle, "config")) == NULL) {
2514 		syslog(LOG_ERR, "lm_load: no 'config' symbol %s", dlerror());
2515 		goto err;
2516 	}
2517 
2518 	/*
2519 	 * Insert it into the right place
2520 	 */
2521 	INSERT_OBJECT_OID(m, &lmodules);
2522 
2523 	/* preserve order */
2524 	if (community == COMM_INITIALIZE) {
2525 		m->flags |= LM_ONSTARTLIST;
2526 		TAILQ_INSERT_TAIL(&modules_start, m, start);
2527 	}
2528 
2529 	/*
2530 	 * make the argument vector.
2531 	 */
2532 	ac = 0;
2533 	for (i = 0; i < nprogargs; i++) {
2534 		if (strlen(progargs[i]) >= strlen(section) + 1 &&
2535 		    strncmp(progargs[i], section, strlen(section)) == 0 &&
2536 		    progargs[i][strlen(section)] == ':') {
2537 			if (ac == MAX_MOD_ARGS) {
2538 				syslog(LOG_WARNING, "too many arguments for "
2539 				    "module '%s", section);
2540 				break;
2541 			}
2542 			av[ac++] = &progargs[i][strlen(section)+1];
2543 		}
2544 	}
2545 	av[ac] = NULL;
2546 
2547 	/*
2548 	 * Run the initialization function
2549 	 */
2550 	if ((err = (*m->config->init)(m, ac, av)) != 0) {
2551 		syslog(LOG_ERR, "lm_load: init failed: %d", err);
2552 		TAILQ_REMOVE(&lmodules, m, link);
2553 		goto err;
2554 	}
2555 
2556 	return (m);
2557 
2558   err:
2559 	if ((m->flags & LM_ONSTARTLIST) != 0)
2560 		TAILQ_REMOVE(&modules_start, m, start);
2561 	if (m->handle)
2562 		dlclose(m->handle);
2563 	free(m->path);
2564 	free(m);
2565 	return (NULL);
2566 }
2567 
2568 /*
2569  * Start a module
2570  */
2571 void
2572 lm_start(struct lmodule *mod)
2573 {
2574 	const struct lmodule *m;
2575 
2576 	/*
2577 	 * Merge tree. If this fails, unload the module.
2578 	 */
2579 	if (tree_merge(mod->config->tree, mod->config->tree_size, mod)) {
2580 		lm_unload(mod);
2581 		return;
2582 	}
2583 
2584 	/*
2585 	 * Read configuration
2586 	 */
2587 	if (read_config(config_file, mod)) {
2588 		syslog(LOG_ERR, "error in config file");
2589 		lm_unload(mod);
2590 		return;
2591 	}
2592 	if (mod->config->start)
2593 		(*mod->config->start)();
2594 
2595 	mod->flags |= LM_STARTED;
2596 
2597 	/*
2598 	 * Inform other modules
2599 	 */
2600 	TAILQ_FOREACH(m, &lmodules, link)
2601 		if (m->config->loading)
2602 			(*m->config->loading)(mod, 1);
2603 }
2604 
2605 
2606 /*
2607  * Unload a module.
2608  */
2609 void
2610 lm_unload(struct lmodule *m)
2611 {
2612 	int err;
2613 	const struct lmodule *mod;
2614 
2615 	TAILQ_REMOVE(&lmodules, m, link);
2616 	if (m->flags & LM_ONSTARTLIST)
2617 		TAILQ_REMOVE(&modules_start, m, start);
2618 	tree_unmerge(m);
2619 
2620 	if ((m->flags & LM_STARTED) && m->config->fini &&
2621 	    (err = (*m->config->fini)()) != 0)
2622 		syslog(LOG_WARNING, "lm_unload(%s): fini %d", m->section, err);
2623 
2624 	comm_flush(m);
2625 	reqid_flush(m);
2626 	timer_flush(m);
2627 	fd_flush(m);
2628 
2629 	dlclose(m->handle);
2630 	free(m->path);
2631 
2632 	/*
2633 	 * Inform other modules
2634 	 */
2635 	TAILQ_FOREACH(mod, &lmodules, link)
2636 		if (mod->config->loading)
2637 			(*mod->config->loading)(m, 0);
2638 
2639 	free(m);
2640 }
2641 
2642 /*
2643  * Register an object resource and return the index (or 0 on failures)
2644  */
2645 u_int
2646 or_register(const struct asn_oid *or, const char *descr, struct lmodule *mod)
2647 {
2648 	struct objres *objres, *or1;
2649 	u_int idx;
2650 
2651 	/* find a free index */
2652 	idx = 1;
2653 	for (objres = TAILQ_FIRST(&objres_list);
2654 	     objres != NULL;
2655 	     objres = TAILQ_NEXT(objres, link)) {
2656 		if ((or1 = TAILQ_NEXT(objres, link)) == NULL ||
2657 		    or1->index > objres->index + 1) {
2658 			idx = objres->index + 1;
2659 			break;
2660 		}
2661 	}
2662 
2663 	if ((objres = malloc(sizeof(*objres))) == NULL)
2664 		return (0);
2665 
2666 	objres->index = idx;
2667 	objres->oid = *or;
2668 	strlcpy(objres->descr, descr, sizeof(objres->descr));
2669 	objres->uptime = (uint32_t)(get_ticks() - start_tick);
2670 	objres->module = mod;
2671 
2672 	INSERT_OBJECT_INT(objres, &objres_list);
2673 
2674 	systemg.or_last_change = objres->uptime;
2675 
2676 	return (idx);
2677 }
2678 
2679 void
2680 or_unregister(u_int idx)
2681 {
2682 	struct objres *objres;
2683 
2684 	TAILQ_FOREACH(objres, &objres_list, link)
2685 		if (objres->index == idx) {
2686 			TAILQ_REMOVE(&objres_list, objres, link);
2687 			free(objres);
2688 			return;
2689 		}
2690 }
2691 
2692 /*
2693  * RFC 3414 User-based Security Model support
2694  */
2695 
2696 struct snmpd_usmstat *
2697 bsnmpd_get_usm_stats(void)
2698 {
2699 	return (&snmpd_usmstats);
2700 }
2701 
2702 void
2703 bsnmpd_reset_usm_stats(void)
2704 {
2705 	memset(&snmpd_usmstats, 0, sizeof(&snmpd_usmstats));
2706 }
2707 
2708 struct usm_user *
2709 usm_first_user(void)
2710 {
2711 	return (SLIST_FIRST(&usm_userlist));
2712 }
2713 
2714 struct usm_user *
2715 usm_next_user(struct usm_user *uuser)
2716 {
2717 	if (uuser == NULL)
2718 		return (NULL);
2719 
2720 	return (SLIST_NEXT(uuser, up));
2721 }
2722 
2723 struct usm_user *
2724 usm_find_user(uint8_t *engine, uint32_t elen, char *uname)
2725 {
2726 	struct usm_user *uuser;
2727 
2728 	SLIST_FOREACH(uuser, &usm_userlist, up)
2729 		if (uuser->user_engine_len == elen &&
2730 		    memcmp(uuser->user_engine_id, engine, elen) == 0 &&
2731 		    strlen(uuser->suser.sec_name) == strlen(uname) &&
2732 		    strcmp(uuser->suser.sec_name, uname) == 0)
2733 			break;
2734 
2735 	return (uuser);
2736 }
2737 
2738 static int
2739 usm_compare_user(struct usm_user *u1, struct usm_user *u2)
2740 {
2741 	uint32_t i;
2742 
2743 	if (u1->user_engine_len < u2->user_engine_len)
2744 		return (-1);
2745 	if (u1->user_engine_len > u2->user_engine_len)
2746 		return (1);
2747 
2748 	for (i = 0; i < u1->user_engine_len; i++) {
2749 		if (u1->user_engine_id[i] < u2->user_engine_id[i])
2750 			return (-1);
2751 		if (u1->user_engine_id[i] > u2->user_engine_id[i])
2752 			return (1);
2753 	}
2754 
2755 	if (strlen(u1->suser.sec_name) < strlen(u2->suser.sec_name))
2756 		return (-1);
2757 	if (strlen(u1->suser.sec_name) > strlen(u2->suser.sec_name))
2758 		return (1);
2759 
2760 	for (i = 0; i < strlen(u1->suser.sec_name); i++) {
2761 		if (u1->suser.sec_name[i] < u2->suser.sec_name[i])
2762 			return (-1);
2763 		if (u1->suser.sec_name[i] > u2->suser.sec_name[i])
2764 			return (1);
2765 	}
2766 
2767 	return (0);
2768 }
2769 
2770 struct usm_user *
2771 usm_new_user(uint8_t *eid, uint32_t elen, char *uname)
2772 {
2773 	int cmp;
2774 	struct usm_user *uuser, *temp, *prev;
2775 
2776 	for (uuser = usm_first_user(); uuser != NULL;
2777 	    (uuser = usm_next_user(uuser))) {
2778 		if (uuser->user_engine_len == elen &&
2779 		    strlen(uname) == strlen(uuser->suser.sec_name) &&
2780 		    strcmp(uname, uuser->suser.sec_name) == 0 &&
2781 		    memcmp(eid, uuser->user_engine_id, elen) == 0)
2782 			return (NULL);
2783 	}
2784 
2785 	if ((uuser = (struct usm_user *)malloc(sizeof(*uuser))) == NULL)
2786 		return (NULL);
2787 
2788 	memset(uuser, 0, sizeof(struct usm_user));
2789 	strlcpy(uuser->suser.sec_name, uname, SNMP_ADM_STR32_SIZ);
2790 	memcpy(uuser->user_engine_id, eid, elen);
2791 	uuser->user_engine_len = elen;
2792 
2793 	if ((prev = SLIST_FIRST(&usm_userlist)) == NULL ||
2794 	    usm_compare_user(uuser, prev) < 0) {
2795 		SLIST_INSERT_HEAD(&usm_userlist, uuser, up);
2796 		return (uuser);
2797 	}
2798 
2799 	SLIST_FOREACH(temp, &usm_userlist, up) {
2800 		if ((cmp = usm_compare_user(uuser, temp)) <= 0)
2801 			break;
2802 		prev = temp;
2803 	}
2804 
2805 	if (temp == NULL || cmp < 0)
2806 		SLIST_INSERT_AFTER(prev, uuser, up);
2807 	else if (cmp > 0)
2808 		SLIST_INSERT_AFTER(temp, uuser, up);
2809 	else {
2810 		syslog(LOG_ERR, "User %s exists", uuser->suser.sec_name);
2811 		free(uuser);
2812 		return (NULL);
2813 	}
2814 
2815 	return (uuser);
2816 }
2817 
2818 void
2819 usm_delete_user(struct usm_user *uuser)
2820 {
2821 	SLIST_REMOVE(&usm_userlist, uuser, usm_user, up);
2822 	free(uuser);
2823 }
2824 
2825 void
2826 usm_flush_users(void)
2827 {
2828 	struct usm_user *uuser;
2829 
2830 	while ((uuser = SLIST_FIRST(&usm_userlist)) != NULL) {
2831 		SLIST_REMOVE_HEAD(&usm_userlist, up);
2832 		free(uuser);
2833 	}
2834 
2835 	SLIST_INIT(&usm_userlist);
2836 }
2837 
2838 /*
2839  * RFC 3415 View-based Access Control Model support
2840  */
2841 struct vacm_user *
2842 vacm_first_user(void)
2843 {
2844 	return (SLIST_FIRST(&vacm_userlist));
2845 }
2846 
2847 struct vacm_user *
2848 vacm_next_user(struct vacm_user *vuser)
2849 {
2850 	if (vuser == NULL)
2851 		return (NULL);
2852 
2853 	return (SLIST_NEXT(vuser, vvu));
2854 }
2855 
2856 static int
2857 vacm_compare_user(struct vacm_user *v1, struct vacm_user *v2)
2858 {
2859 	uint32_t i;
2860 
2861 	if (v1->sec_model < v2->sec_model)
2862 		return (-1);
2863 	if (v1->sec_model > v2->sec_model)
2864 		return (1);
2865 
2866 	if (strlen(v1->secname) < strlen(v2->secname))
2867 		return (-1);
2868 	if (strlen(v1->secname) > strlen(v2->secname))
2869 		return (1);
2870 
2871 	for (i = 0; i < strlen(v1->secname); i++) {
2872 		if (v1->secname[i] < v2->secname[i])
2873 			return (-1);
2874 		if (v1->secname[i] > v2->secname[i])
2875 			return (1);
2876 	}
2877 
2878 	return (0);
2879 }
2880 
2881 struct vacm_user *
2882 vacm_new_user(int32_t smodel, char *uname)
2883 {
2884 	int cmp;
2885 	struct vacm_user *user, *temp, *prev;
2886 
2887 	SLIST_FOREACH(user, &vacm_userlist, vvu)
2888 		if (strcmp(uname, user->secname) == 0 &&
2889 		    smodel == user->sec_model)
2890 			return (NULL);
2891 
2892 	if ((user = (struct vacm_user *)malloc(sizeof(*user))) == NULL)
2893 		return (NULL);
2894 
2895 	memset(user, 0, sizeof(*user));
2896 	user->group = &vacm_default_group;
2897 	SLIST_INSERT_HEAD(&vacm_default_group.group_users, user, vvg);
2898 	user->sec_model = smodel;
2899 	strlcpy(user->secname, uname, sizeof(user->secname));
2900 
2901 	if ((prev = SLIST_FIRST(&vacm_userlist)) == NULL ||
2902 	    vacm_compare_user(user, prev) < 0) {
2903 		SLIST_INSERT_HEAD(&vacm_userlist, user, vvu);
2904 		return (user);
2905 	}
2906 
2907 	SLIST_FOREACH(temp, &vacm_userlist, vvu) {
2908 		if ((cmp = vacm_compare_user(user, temp)) <= 0)
2909 			break;
2910 		prev = temp;
2911 	}
2912 
2913 	if (temp == NULL || cmp < 0)
2914 		SLIST_INSERT_AFTER(prev, user, vvu);
2915 	else if (cmp > 0)
2916 		SLIST_INSERT_AFTER(temp, user, vvu);
2917 	else {
2918 		syslog(LOG_ERR, "User %s exists", user->secname);
2919 		free(user);
2920 		return (NULL);
2921 	}
2922 
2923 	return (user);
2924 }
2925 
2926 int
2927 vacm_delete_user(struct vacm_user *user)
2928 {
2929 	if (user->group != NULL && user->group != &vacm_default_group) {
2930 		SLIST_REMOVE(&user->group->group_users, user, vacm_user, vvg);
2931 		if (SLIST_EMPTY(&user->group->group_users)) {
2932 			SLIST_REMOVE(&vacm_grouplist, user->group,
2933 			    vacm_group, vge);
2934 			free(user->group);
2935 		}
2936 	}
2937 
2938 	SLIST_REMOVE(&vacm_userlist, user, vacm_user, vvu);
2939 	free(user);
2940 
2941 	return (0);
2942 }
2943 
2944 int
2945 vacm_user_set_group(struct vacm_user *user, u_char *octets, u_int len)
2946 {
2947 	struct vacm_group *group;
2948 
2949 	if (len >= SNMP_ADM_STR32_SIZ)
2950 		return (-1);
2951 
2952 	SLIST_FOREACH(group, &vacm_grouplist, vge)
2953 		if (strlen(group->groupname) == len &&
2954 		    memcmp(octets, group->groupname, len) == 0)
2955 			break;
2956 
2957 	if (group == NULL) {
2958 		if ((group = (struct vacm_group *)malloc(sizeof(*group))) == NULL)
2959 			return (-1);
2960 		memset(group, 0, sizeof(*group));
2961 		memcpy(group->groupname, octets, len);
2962 		group->groupname[len] = '\0';
2963 		SLIST_INSERT_HEAD(&vacm_grouplist, group, vge);
2964 	}
2965 
2966 	SLIST_REMOVE(&user->group->group_users, user, vacm_user, vvg);
2967 	SLIST_INSERT_HEAD(&group->group_users, user, vvg);
2968 	user->group = group;
2969 
2970 	return (0);
2971 }
2972 
2973 void
2974 vacm_groups_init(void)
2975 {
2976 	SLIST_INSERT_HEAD(&vacm_grouplist, &vacm_default_group, vge);
2977 }
2978 
2979 struct vacm_access *
2980 vacm_first_access_rule(void)
2981 {
2982 	return (TAILQ_FIRST(&vacm_accesslist));
2983 }
2984 
2985 struct vacm_access *
2986 vacm_next_access_rule(struct vacm_access *acl)
2987 {
2988 	if (acl == NULL)
2989 		return (NULL);
2990 
2991 	return (TAILQ_NEXT(acl, vva));
2992 }
2993 
2994 static int
2995 vacm_compare_access_rule(struct vacm_access *v1, struct vacm_access *v2)
2996 {
2997 	uint32_t i;
2998 
2999 	if (strlen(v1->group->groupname) < strlen(v2->group->groupname))
3000 		return (-1);
3001 	if (strlen(v1->group->groupname) > strlen(v2->group->groupname))
3002 		return (1);
3003 
3004 	for (i = 0; i < strlen(v1->group->groupname); i++) {
3005 		if (v1->group->groupname[i] < v2->group->groupname[i])
3006 			return (-1);
3007 		if (v1->group->groupname[i] > v2->group->groupname[i])
3008 			return (1);
3009 	}
3010 
3011 	if (strlen(v1->ctx_prefix) < strlen(v2->ctx_prefix))
3012 		return (-1);
3013 	if (strlen(v1->ctx_prefix) > strlen(v2->ctx_prefix))
3014 		return (1);
3015 
3016 	for (i = 0; i < strlen(v1->ctx_prefix); i++) {
3017 		if (v1->ctx_prefix[i] < v2->ctx_prefix[i])
3018 			return (-1);
3019 		if (v1->ctx_prefix[i] > v2->ctx_prefix[i])
3020 			return (1);
3021 	}
3022 
3023 	if (v1->sec_model < v2->sec_model)
3024 		return (-1);
3025 	if (v1->sec_model > v2->sec_model)
3026 		return (1);
3027 
3028 	if (v1->sec_level < v2->sec_level)
3029 		return (-1);
3030 	if (v1->sec_level > v2->sec_level)
3031 		return (1);
3032 
3033 	return (0);
3034 }
3035 
3036 struct vacm_access *
3037 vacm_new_access_rule(char *gname, char *cprefix, int32_t smodel, int32_t slevel)
3038 {
3039 	struct vacm_group *group;
3040 	struct vacm_access *acl, *temp;
3041 
3042 	TAILQ_FOREACH(acl, &vacm_accesslist, vva) {
3043 		if (acl->group == NULL)
3044 			continue;
3045 		if (strcmp(gname, acl->group->groupname) == 0 &&
3046 		    strcmp(cprefix, acl->ctx_prefix) == 0 &&
3047 		    acl->sec_model == smodel && acl->sec_level == slevel)
3048 			return (NULL);
3049 	}
3050 
3051 	/* Make sure the group exists */
3052 	SLIST_FOREACH(group, &vacm_grouplist, vge)
3053 		if (strcmp(gname, group->groupname) == 0)
3054 			break;
3055 
3056 	if (group == NULL)
3057 		return (NULL);
3058 
3059 	if ((acl = (struct vacm_access *)malloc(sizeof(*acl))) == NULL)
3060 		return (NULL);
3061 
3062 	memset(acl, 0, sizeof(*acl));
3063 	acl->group = group;
3064 	strlcpy(acl->ctx_prefix, cprefix, sizeof(acl->ctx_prefix));
3065 	acl->sec_model = smodel;
3066 	acl->sec_level = slevel;
3067 
3068 	if ((temp = TAILQ_FIRST(&vacm_accesslist)) == NULL ||
3069 	    vacm_compare_access_rule(acl, temp) < 0) {
3070 		TAILQ_INSERT_HEAD(&vacm_accesslist, acl, vva);
3071 		return (acl);
3072 	}
3073 
3074 	TAILQ_FOREACH(temp, &vacm_accesslist, vva)
3075 		if (vacm_compare_access_rule(acl, temp) < 0) {
3076 		    	TAILQ_INSERT_BEFORE(temp, acl, vva);
3077 			return (acl);
3078 		}
3079 
3080 	TAILQ_INSERT_TAIL(&vacm_accesslist, acl, vva);
3081 
3082 	return (acl);
3083 }
3084 
3085 int
3086 vacm_delete_access_rule(struct vacm_access *acl)
3087 {
3088 	TAILQ_REMOVE(&vacm_accesslist, acl, vva);
3089 	free(acl);
3090 
3091 	return (0);
3092 }
3093 
3094 struct vacm_view *
3095 vacm_first_view(void)
3096 {
3097 	return (SLIST_FIRST(&vacm_viewlist));
3098 }
3099 
3100 struct vacm_view *
3101 vacm_next_view(struct vacm_view *view)
3102 {
3103 	if (view == NULL)
3104 		return (NULL);
3105 
3106 	return (SLIST_NEXT(view, vvl));
3107 }
3108 
3109 static int
3110 vacm_compare_view(struct vacm_view *v1, struct vacm_view *v2)
3111 {
3112 	uint32_t i;
3113 
3114 	if (strlen(v1->viewname) < strlen(v2->viewname))
3115 		return (-1);
3116 	if (strlen(v1->viewname) > strlen(v2->viewname))
3117 		return (1);
3118 
3119 	for (i = 0; i < strlen(v1->viewname); i++) {
3120 		if (v1->viewname[i] < v2->viewname[i])
3121 			return (-1);
3122 		if (v1->viewname[i] > v2->viewname[i])
3123 			return (1);
3124 	}
3125 
3126 	return (asn_compare_oid(&v1->subtree, &v2->subtree));
3127 }
3128 
3129 struct vacm_view *
3130 vacm_new_view(char *vname, struct asn_oid *oid)
3131 {
3132 	int cmp;
3133 	struct vacm_view *view, *temp, *prev;
3134 
3135 	SLIST_FOREACH(view, &vacm_viewlist, vvl)
3136 		if (strcmp(vname, view->viewname) == 0)
3137 			return (NULL);
3138 
3139 	if ((view = (struct vacm_view *)malloc(sizeof(*view))) == NULL)
3140 		return (NULL);
3141 
3142 	memset(view, 0, sizeof(*view));
3143 	strlcpy(view->viewname, vname, sizeof(view->viewname));
3144 	asn_append_oid(&view->subtree, oid);
3145 
3146 	if ((prev = SLIST_FIRST(&vacm_viewlist)) == NULL ||
3147 	    vacm_compare_view(view, prev) < 0) {
3148 		SLIST_INSERT_HEAD(&vacm_viewlist, view, vvl);
3149 		return (view);
3150 	}
3151 
3152 	SLIST_FOREACH(temp, &vacm_viewlist, vvl) {
3153 		if ((cmp = vacm_compare_view(view, temp)) <= 0)
3154 			break;
3155 		prev = temp;
3156 	}
3157 
3158 	if (temp == NULL || cmp < 0)
3159 		SLIST_INSERT_AFTER(prev, view, vvl);
3160 	else if (cmp > 0)
3161 		SLIST_INSERT_AFTER(temp, view, vvl);
3162 	else {
3163 		syslog(LOG_ERR, "View %s exists", view->viewname);
3164 		free(view);
3165 		return (NULL);
3166 	}
3167 
3168 	return (view);
3169 }
3170 
3171 int
3172 vacm_delete_view(struct vacm_view *view)
3173 {
3174 	SLIST_REMOVE(&vacm_viewlist, view, vacm_view, vvl);
3175 	free(view);
3176 
3177 	return (0);
3178 }
3179 
3180 struct vacm_context *
3181 vacm_first_context(void)
3182 {
3183 	return (SLIST_FIRST(&vacm_contextlist));
3184 }
3185 
3186 struct vacm_context *
3187 vacm_next_context(struct vacm_context *vacmctx)
3188 {
3189 	if (vacmctx == NULL)
3190 		return (NULL);
3191 
3192 	return (SLIST_NEXT(vacmctx, vcl));
3193 }
3194 
3195 struct vacm_context *
3196 vacm_add_context(char *ctxname, int regid)
3197 {
3198 	int cmp;
3199 	struct vacm_context *ctx, *temp, *prev;
3200 
3201 	SLIST_FOREACH(ctx, &vacm_contextlist, vcl)
3202 		if (strcmp(ctxname, ctx->ctxname) == 0) {
3203 			syslog(LOG_ERR, "Context %s exists", ctx->ctxname);
3204 			return (NULL);
3205 		}
3206 
3207 	if ((ctx = (struct vacm_context *)malloc(sizeof(*ctx))) == NULL)
3208 		return (NULL);
3209 
3210 	memset(ctx, 0, sizeof(*ctx));
3211 	strlcpy(ctx->ctxname, ctxname, sizeof(ctx->ctxname));
3212 	ctx->regid = regid;
3213 
3214 	if ((prev = SLIST_FIRST(&vacm_contextlist)) == NULL ||
3215 	    strlen(ctx->ctxname) < strlen(prev->ctxname) ||
3216 	    strcmp(ctx->ctxname, prev->ctxname) < 0) {
3217 		SLIST_INSERT_HEAD(&vacm_contextlist, ctx, vcl);
3218 		return (ctx);
3219 	}
3220 
3221 	SLIST_FOREACH(temp, &vacm_contextlist, vcl) {
3222 		if (strlen(ctx->ctxname) < strlen(temp->ctxname) ||
3223 		    strcmp(ctx->ctxname, temp->ctxname) < 0) {
3224 		    	cmp = -1;
3225 			break;
3226 		}
3227 		prev = temp;
3228 	}
3229 
3230 	if (temp == NULL || cmp < 0)
3231 		SLIST_INSERT_AFTER(prev, ctx, vcl);
3232 	else if (cmp > 0)
3233 		SLIST_INSERT_AFTER(temp, ctx, vcl);
3234 	else {
3235 		syslog(LOG_ERR, "Context %s exists", ctx->ctxname);
3236 		free(ctx);
3237 		return (NULL);
3238 	}
3239 
3240 	return (ctx);
3241 }
3242 
3243 void
3244 vacm_flush_contexts(int regid)
3245 {
3246 	struct vacm_context *ctx, *temp;
3247 
3248 	SLIST_FOREACH_SAFE(ctx, &vacm_contextlist, vcl, temp)
3249 		if (ctx->regid == regid) {
3250 			SLIST_REMOVE(&vacm_contextlist, ctx, vacm_context, vcl);
3251 			free(ctx);
3252 		}
3253 }
3254