xref: /freebsd/contrib/bsnmp/snmpd/main.c (revision 8b959dd6a3921c35395bef4a6d7ad2426a3bd88e)
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 
57 #ifdef USE_TCPWRAPPERS
58 #include <arpa/inet.h>
59 #include <tcpd.h>
60 #endif
61 
62 #include "support.h"
63 #include "snmpmod.h"
64 #include "snmpd.h"
65 #include "tree.h"
66 #include "oid.h"
67 
68 #include "trans_inet.h"
69 
70 #define	PATH_PID	"/var/run/%s.pid"
71 #define PATH_CONFIG	"/etc/%s.config"
72 #define	PATH_ENGINE	"/var/%s.engine"
73 
74 uint64_t this_tick;	/* start of processing of current packet (absolute) */
75 uint64_t start_tick;	/* start of processing */
76 
77 struct systemg systemg = {
78 	NULL,
79 	{ 8, { 1, 3, 6, 1, 4, 1, 1115, 7352 }},
80 	NULL, NULL, NULL,
81 	64 + 8 + 4,
82 	0
83 };
84 struct debug debug = {
85 	0,		/* dump_pdus */
86 	LOG_DEBUG,	/* log_pri */
87 	0,		/* evdebug */
88 };
89 
90 struct snmpd snmpd = {
91 	2048,		/* txbuf */
92 	2048,		/* rxbuf */
93 	0,		/* comm_dis */
94 	0,		/* auth_traps */
95 	{0, 0, 0, 0},	/* trap1addr */
96 	VERS_ENABLE_ALL,/* version_enable */
97 };
98 struct snmpd_stats snmpd_stats;
99 
100 struct snmpd_usmstat snmpd_usmstats;
101 
102 /* snmpEngine */
103 struct snmp_engine snmpd_engine;
104 
105 /* snmpSerialNo */
106 int32_t snmp_serial_no;
107 
108 struct snmpd_target_stats snmpd_target_stats;
109 
110 /* search path for config files */
111 const char *syspath = PATH_SYSCONFIG;
112 
113 /* list of all loaded modules */
114 struct lmodules lmodules = TAILQ_HEAD_INITIALIZER(lmodules);
115 
116 /* list of loaded modules during start-up in the order they were loaded */
117 static struct lmodules modules_start = TAILQ_HEAD_INITIALIZER(modules_start);
118 
119 /* list of all known communities */
120 struct community_list community_list = TAILQ_HEAD_INITIALIZER(community_list);
121 
122 /* list of all known USM users */
123 static struct usm_userlist usm_userlist = SLIST_HEAD_INITIALIZER(usm_userlist);
124 
125 /* A list of all VACM users configured, including v1, v2c and v3 */
126 static struct vacm_userlist vacm_userlist =
127     SLIST_HEAD_INITIALIZER(vacm_userlist);
128 
129 /* A list of all VACM groups */
130 static struct vacm_grouplist vacm_grouplist =
131     SLIST_HEAD_INITIALIZER(vacm_grouplist);
132 
133 static struct vacm_group vacm_default_group = {
134 	.groupname = "",
135 };
136 
137 /* The list of configured access entries */
138 static struct vacm_accesslist vacm_accesslist =
139     TAILQ_HEAD_INITIALIZER(vacm_accesslist);
140 
141 /* The list of configured views */
142 static struct vacm_viewlist vacm_viewlist =
143     SLIST_HEAD_INITIALIZER(vacm_viewlist);
144 
145 /* The list of configured contexts */
146 static struct vacm_contextlist vacm_contextlist =
147     SLIST_HEAD_INITIALIZER(vacm_contextlist);
148 
149 /* list of all installed object resources */
150 struct objres_list objres_list = TAILQ_HEAD_INITIALIZER(objres_list);
151 
152 /* community value generator */
153 static u_int next_community_index = 1;
154 
155 /* list of all known ranges */
156 struct idrange_list idrange_list = TAILQ_HEAD_INITIALIZER(idrange_list);
157 
158 /* identifier generator */
159 u_int next_idrange = 1;
160 
161 /* list of all current timers */
162 struct timer_list timer_list = LIST_HEAD_INITIALIZER(timer_list);
163 
164 /* list of file descriptors */
165 struct fdesc_list fdesc_list = LIST_HEAD_INITIALIZER(fdesc_list);
166 
167 /* program arguments */
168 static char **progargs;
169 static int nprogargs;
170 
171 /* current community */
172 u_int	community;
173 static struct community *comm;
174 
175 /* current USM user */
176 struct usm_user *usm_user;
177 
178 /* file names */
179 static char config_file[MAXPATHLEN + 1];
180 static char pid_file[MAXPATHLEN + 1];
181 char engine_file[MAXPATHLEN + 1];
182 
183 #ifndef USE_LIBBEGEMOT
184 /* event context */
185 static evContext evctx;
186 #endif
187 
188 /* signal mask */
189 static sigset_t blocked_sigs;
190 
191 /* signal handling */
192 static int work;
193 #define	WORK_DOINFO	0x0001
194 #define	WORK_RECONFIG	0x0002
195 
196 /* oids */
197 static const struct asn_oid
198 	oid_snmpMIB = OIDX_snmpMIB,
199 	oid_begemotSnmpd = OIDX_begemotSnmpd,
200 	oid_coldStart = OIDX_coldStart,
201 	oid_authenticationFailure = OIDX_authenticationFailure;
202 
203 const struct asn_oid oid_zeroDotZero = { 2, { 0, 0 }};
204 
205 const struct asn_oid oid_usmUnknownEngineIDs =
206 	{ 11, { 1, 3, 6, 1, 6, 3, 15, 1, 1, 4, 0}};
207 
208 const struct asn_oid oid_usmNotInTimeWindows =
209 	{ 11, { 1, 3, 6, 1, 6, 3, 15, 1, 1, 2, 0}};
210 
211 /* request id generator for traps */
212 u_int trap_reqid;
213 
214 /* help text */
215 static const char usgtxt[] = "\
216 Begemot simple SNMP daemon. Copyright (c) 2001-2002 Fraunhofer Institute for\n\
217 Open Communication Systems (FhG Fokus). All rights reserved.\n\
218 Copyright (c) 2010 The FreeBSD Foundation. All rights reserved.\n\
219 usage: snmpd [-dh] [-c file] [-D options] [-e file] [-I path]\n\
220              [-l prefix] [-m variable=value] [-p file]\n\
221 options:\n\
222   -d		don't daemonize\n\
223   -h		print this info\n\
224   -c file	specify configuration file\n\
225   -D options	debugging options\n\
226   -e file	specify engine id file\n\
227   -I path	system include path\n\
228   -l prefix	default basename for pid and config file\n\
229   -m var=val	define variable\n\
230   -p file	specify pid file\n\
231 ";
232 
233 /* hosts_access(3) request */
234 #ifdef USE_TCPWRAPPERS
235 static struct request_info req;
236 #endif
237 
238 /* transports */
239 extern const struct transport_def udp_trans;
240 extern const struct transport_def lsock_trans;
241 
242 struct transport_list transport_list = TAILQ_HEAD_INITIALIZER(transport_list);
243 
244 /* forward declarations */
245 static void snmp_printf_func(const char *fmt, ...);
246 static void snmp_error_func(const char *err, ...);
247 static void snmp_debug_func(const char *err, ...);
248 static void asn_error_func(const struct asn_buf *b, const char *err, ...);
249 
250 /*
251  * Allocate rx/tx buffer. We allocate one byte more for rx.
252  */
253 void *
buf_alloc(int tx)254 buf_alloc(int tx)
255 {
256 	void *buf;
257 
258 	if ((buf = malloc(tx ? snmpd.txbuf : snmpd.rxbuf)) == NULL) {
259 		syslog(LOG_CRIT, "cannot allocate buffer");
260 		if (tx)
261 			snmpd_stats.noTxbuf++;
262 		else
263 			snmpd_stats.noRxbuf++;
264 		return (NULL);
265 	}
266 	return (buf);
267 }
268 
269 /*
270  * Return the buffer size.
271  */
272 size_t
buf_size(int tx)273 buf_size(int tx)
274 {
275 	return (tx ? snmpd.txbuf : snmpd.rxbuf);
276 }
277 
278 /*
279  * Prepare a PDU for output
280  */
281 void
snmp_output(struct snmp_pdu * pdu,u_char * sndbuf,size_t * sndlen,const char * dest)282 snmp_output(struct snmp_pdu *pdu, u_char *sndbuf, size_t *sndlen,
283     const char *dest)
284 {
285 	struct asn_buf resp_b;
286 	enum snmp_code code;
287 
288 	resp_b.asn_ptr = sndbuf;
289 	resp_b.asn_len = snmpd.txbuf;
290 
291 	if ((code = snmp_pdu_encode(pdu, &resp_b)) != SNMP_CODE_OK) {
292 		syslog(LOG_ERR, "cannot encode message (code=%d)", code);
293 		abort();
294 	}
295 	if (debug.dump_pdus) {
296 		snmp_printf("%s <- ", dest);
297 		snmp_pdu_dump(pdu);
298 	}
299 	*sndlen = (size_t)(resp_b.asn_ptr - sndbuf);
300 }
301 
302 /*
303  * Check USM PDU header credentials against local SNMP Engine & users.
304  */
305 static enum snmp_code
snmp_pdu_auth_user(struct snmp_pdu * pdu)306 snmp_pdu_auth_user(struct snmp_pdu *pdu)
307 {
308 	usm_user = NULL;
309 
310 	/* un-authenticated snmpEngineId discovery */
311 	if (pdu->engine.engine_len == 0 && strlen(pdu->user.sec_name) == 0) {
312 		pdu->engine.engine_len = snmpd_engine.engine_len;
313 		memcpy(pdu->engine.engine_id, snmpd_engine.engine_id,
314 		    snmpd_engine.engine_len);
315 		update_snmpd_engine_time();
316 		pdu->engine.engine_boots = snmpd_engine.engine_boots;
317 		pdu->engine.engine_time = snmpd_engine.engine_time;
318 		pdu->flags |= SNMP_MSG_AUTODISCOVER;
319 		return (SNMP_CODE_OK);
320 	}
321 
322 	if ((usm_user = usm_find_user(pdu->engine.engine_id,
323 	    pdu->engine.engine_len, pdu->user.sec_name)) == NULL ||
324 	    usm_user->status != 1 /* active */)
325 		return (SNMP_CODE_BADUSER);
326 
327 	if (usm_user->user_engine_len != snmpd_engine.engine_len ||
328 	    memcmp(usm_user->user_engine_id, snmpd_engine.engine_id,
329 	    snmpd_engine.engine_len) != 0)
330 		return (SNMP_CODE_BADENGINE);
331 
332 	pdu->user.priv_proto = usm_user->suser.priv_proto;
333 	memcpy(pdu->user.priv_key, usm_user->suser.priv_key,
334 	    sizeof(pdu->user.priv_key));
335 
336 	/* authenticated snmpEngineId discovery */
337 	if ((pdu->flags & SNMP_MSG_AUTH_FLAG) != 0) {
338 		update_snmpd_engine_time();
339 		pdu->user.auth_proto = usm_user->suser.auth_proto;
340 		memcpy(pdu->user.auth_key, usm_user->suser.auth_key,
341 		    sizeof(pdu->user.auth_key));
342 
343 		if (pdu->engine.engine_boots == 0 &&
344 		    pdu->engine.engine_time == 0) {
345 			update_snmpd_engine_time();
346 		    	pdu->flags |= SNMP_MSG_AUTODISCOVER;
347 			return (SNMP_CODE_OK);
348 		}
349 
350 		if (pdu->engine.engine_boots != snmpd_engine.engine_boots ||
351 		    abs(pdu->engine.engine_time - snmpd_engine.engine_time) >
352 		    SNMP_TIME_WINDOW)
353 			return (SNMP_CODE_NOTINTIME);
354 	}
355 
356 	if (((pdu->flags & SNMP_MSG_PRIV_FLAG) != 0 &&
357 	    (pdu->flags & SNMP_MSG_AUTH_FLAG) == 0) ||
358 	    ((pdu->flags & SNMP_MSG_AUTH_FLAG) == 0 &&
359 	    usm_user->suser.auth_proto != SNMP_AUTH_NOAUTH) ||
360 	    ((pdu->flags & SNMP_MSG_PRIV_FLAG) == 0 &&
361 	    usm_user->suser.priv_proto != SNMP_PRIV_NOPRIV))
362 		return (SNMP_CODE_BADSECLEVEL);
363 
364 	return (SNMP_CODE_OK);
365 }
366 
367 /*
368  * Check whether access to each of var bindings in the PDU is allowed based
369  * on the user credentials against the configured User groups & VACM views.
370  */
371 enum snmp_code
snmp_pdu_auth_access(struct snmp_pdu * pdu,int32_t * ip)372 snmp_pdu_auth_access(struct snmp_pdu *pdu, int32_t *ip)
373 {
374 	const char *uname;
375 	int32_t suboid, smodel;
376 	uint32_t i;
377 	struct vacm_user *vuser;
378 	struct vacm_access *acl;
379 	struct vacm_context *vacmctx;
380 	struct vacm_view *view;
381 
382 	/*
383 	 * At least a default context exists if the snmpd_vacm(3) module is
384 	 * running.
385 	 */
386 	if (SLIST_EMPTY(&vacm_contextlist) ||
387 	    (pdu->flags & SNMP_MSG_AUTODISCOVER) != 0)
388 		return (SNMP_CODE_OK);
389 
390 	switch (pdu->version) {
391 	case SNMP_V1:
392 		if ((uname = comm_string(community)) == NULL)
393 			return (SNMP_CODE_FAILED);
394 		smodel = SNMP_SECMODEL_SNMPv1;
395 		break;
396 
397 	case SNMP_V2c:
398 		if ((uname = comm_string(community)) == NULL)
399 			return (SNMP_CODE_FAILED);
400 		smodel = SNMP_SECMODEL_SNMPv2c;
401 		break;
402 
403 	case SNMP_V3:
404 		uname = pdu->user.sec_name;
405 		if ((smodel = pdu->security_model) !=  SNMP_SECMODEL_USM)
406 			return (SNMP_CODE_FAILED);
407 		/* Compare the PDU context engine id against the agent's */
408 		if (pdu->context_engine_len != snmpd_engine.engine_len ||
409 		    memcmp(pdu->context_engine, snmpd_engine.engine_id,
410 		    snmpd_engine.engine_len) != 0)
411 			return (SNMP_CODE_FAILED);
412 		break;
413 
414 	default:
415 		abort();
416 	}
417 
418 	SLIST_FOREACH(vuser, &vacm_userlist, vvu)
419 		if (strcmp(uname, vuser->secname) == 0 &&
420 		    vuser->sec_model == smodel)
421 			break;
422 
423 	if (vuser == NULL || vuser->group == NULL)
424 		return (SNMP_CODE_FAILED);
425 
426 	/* XXX: shteryana - recheck */
427 	TAILQ_FOREACH_REVERSE(acl, &vacm_accesslist, vacm_accesslist, vva) {
428 		if (acl->group != vuser->group)
429 			continue;
430 		SLIST_FOREACH(vacmctx, &vacm_contextlist, vcl)
431 			if (memcmp(vacmctx->ctxname, acl->ctx_prefix,
432 			    acl->ctx_match) == 0)
433 				goto match;
434 	}
435 
436 	return (SNMP_CODE_FAILED);
437 
438 match:
439 
440 	switch (pdu->type) {
441 	case SNMP_PDU_GET:
442 	case SNMP_PDU_GETNEXT:
443 	case SNMP_PDU_GETBULK:
444 		if ((view = acl->read_view) == NULL)
445 			return (SNMP_CODE_FAILED);
446 		break;
447 
448 	case SNMP_PDU_SET:
449 		if ((view = acl->write_view) == NULL)
450 			return (SNMP_CODE_FAILED);
451 		break;
452 
453 	case SNMP_PDU_TRAP:
454 	case SNMP_PDU_INFORM:
455 	case SNMP_PDU_TRAP2:
456 	case SNMP_PDU_REPORT:
457 		if ((view = acl->notify_view) == NULL)
458 			return (SNMP_CODE_FAILED);
459 		break;
460 	case SNMP_PDU_RESPONSE:
461 		/* NOTREACHED */
462 			return (SNMP_CODE_FAILED);
463 	default:
464 		abort();
465 	}
466 
467 	for (i = 0; i < pdu->nbindings; i++) {
468 		/* XXX - view->mask*/
469 		suboid = asn_is_suboid(&view->subtree, &pdu->bindings[i].var);
470 		if ((!suboid && !view->exclude) || (suboid && view->exclude)) {
471 			*ip = i + 1;
472 			return (SNMP_CODE_FAILED);
473 		}
474 	}
475 
476 	return (SNMP_CODE_OK);
477 }
478 
479 /*
480  * SNMP input. Start: decode the PDU, find the user or community.
481  */
482 enum snmpd_input_err
snmp_input_start(const u_char * buf,size_t len,const char * source,struct snmp_pdu * pdu,int32_t * ip,size_t * pdulen)483 snmp_input_start(const u_char *buf, size_t len, const char *source,
484     struct snmp_pdu *pdu, int32_t *ip, size_t *pdulen)
485 {
486 	struct asn_buf b;
487 	enum snmp_code code;
488 	enum snmpd_input_err ret;
489 	int sret;
490 
491 	/* update uptime */
492 	this_tick = get_ticks();
493 
494 	b.asn_cptr = buf;
495 	b.asn_len = len;
496 
497 	ret = SNMPD_INPUT_OK;
498 
499 	/* look whether we have enough bytes for the entire PDU. */
500 	switch (sret = snmp_pdu_snoop(&b)) {
501 
502 	  case 0:
503 		return (SNMPD_INPUT_TRUNC);
504 
505 	  case -1:
506 		snmpd_stats.inASNParseErrs++;
507 		return (SNMPD_INPUT_FAILED);
508 	}
509 	b.asn_len = *pdulen = (size_t)sret;
510 
511 	memset(pdu, 0, sizeof(*pdu));
512 	if ((code = snmp_pdu_decode_header(&b, pdu)) != SNMP_CODE_OK)
513 		goto decoded;
514 
515 	if (pdu->version == SNMP_V3) {
516 		if (pdu->security_model != SNMP_SECMODEL_USM) {
517 			code = SNMP_CODE_FAILED;
518 			goto decoded;
519 		}
520 		if ((code = snmp_pdu_auth_user(pdu)) != SNMP_CODE_OK)
521 		    	goto decoded;
522 		if ((code =  snmp_pdu_decode_secmode(&b, pdu)) != SNMP_CODE_OK)
523 			goto decoded;
524 	}
525 	code = snmp_pdu_decode_scoped(&b, pdu, ip);
526 
527 decoded:
528 	snmpd_stats.inPkts++;
529 
530 	switch (code) {
531 
532 	  case SNMP_CODE_FAILED:
533 		snmpd_stats.inASNParseErrs++;
534 		return (SNMPD_INPUT_FAILED);
535 
536 	  case SNMP_CODE_BADVERS:
537 	  bad_vers:
538 		snmpd_stats.inBadVersions++;
539 		return (SNMPD_INPUT_FAILED);
540 
541 	  case SNMP_CODE_BADLEN:
542 		if (pdu->type == SNMP_OP_SET)
543 			ret = SNMPD_INPUT_VALBADLEN;
544 		break;
545 
546 	  case SNMP_CODE_OORANGE:
547 		if (pdu->type == SNMP_OP_SET)
548 			ret = SNMPD_INPUT_VALRANGE;
549 		break;
550 
551 	  case SNMP_CODE_BADENC:
552 		if (pdu->type == SNMP_OP_SET)
553 			ret = SNMPD_INPUT_VALBADENC;
554 		break;
555 
556 	  case SNMP_CODE_BADSECLEVEL:
557 		snmpd_usmstats.unsupported_seclevels++;
558 		return (SNMPD_INPUT_FAILED);
559 
560 	  case SNMP_CODE_NOTINTIME:
561 		snmpd_usmstats.not_in_time_windows++;
562 		return (SNMPD_INPUT_FAILED);
563 
564 	  case SNMP_CODE_BADUSER:
565 		snmpd_usmstats.unknown_users++;
566 		return (SNMPD_INPUT_FAILED);
567 
568 	  case SNMP_CODE_BADENGINE:
569 		snmpd_usmstats.unknown_engine_ids++;
570 		return (SNMPD_INPUT_FAILED);
571 
572 	  case SNMP_CODE_BADDIGEST:
573 		snmpd_usmstats.wrong_digests++;
574 		return (SNMPD_INPUT_FAILED);
575 
576 	  case SNMP_CODE_EDECRYPT:
577 		snmpd_usmstats.decrypt_errors++;
578 		return (SNMPD_INPUT_FAILED);
579 
580 	  case SNMP_CODE_OK:
581 		switch (pdu->version) {
582 
583 		  case SNMP_V1:
584 			if (!(snmpd.version_enable & VERS_ENABLE_V1))
585 				goto bad_vers;
586 			break;
587 
588 		  case SNMP_V2c:
589 			if (!(snmpd.version_enable & VERS_ENABLE_V2C))
590 				goto bad_vers;
591 			break;
592 
593 		  case SNMP_V3:
594 		  	if (!(snmpd.version_enable & VERS_ENABLE_V3))
595 				goto bad_vers;
596 			break;
597 
598 		  case SNMP_Verr:
599 			goto bad_vers;
600 		}
601 		break;
602 	}
603 
604 	if (debug.dump_pdus) {
605 		snmp_printf("%s -> ", source);
606 		snmp_pdu_dump(pdu);
607 	}
608 
609 	/*
610 	 * Look, whether we know the community or user
611 	 */
612 
613 	if (pdu->version != SNMP_V3) {
614 		TAILQ_FOREACH(comm, &community_list, link)
615 			if (comm->string != NULL &&
616 			    strcmp(comm->string, pdu->community) == 0)
617 				break;
618 
619 		if (comm == NULL) {
620 			snmpd_stats.inBadCommunityNames++;
621 			snmp_pdu_free(pdu);
622 			if (snmpd.auth_traps)
623 				snmp_send_trap(&oid_authenticationFailure,
624 				    (struct snmp_value *)NULL);
625 			ret = SNMPD_INPUT_BAD_COMM;
626 		} else
627 			community = comm->value;
628 	} else if (pdu->nbindings == 0) {
629 		/* RFC 3414 - snmpEngineID Discovery */
630 		if (strlen(pdu->user.sec_name) == 0) {
631 			asn_append_oid(&(pdu->bindings[pdu->nbindings++].var),
632 			    &oid_usmUnknownEngineIDs);
633 			pdu->context_engine_len = snmpd_engine.engine_len;
634 			memcpy(pdu->context_engine, snmpd_engine.engine_id,
635 			    snmpd_engine.engine_len);
636 		} else if (pdu->engine.engine_boots == 0 &&
637 		    pdu->engine.engine_time == 0) {
638 			asn_append_oid(&(pdu->bindings[pdu->nbindings++].var),
639 			    &oid_usmNotInTimeWindows);
640 			update_snmpd_engine_time();
641 			pdu->engine.engine_boots = snmpd_engine.engine_boots;
642 			pdu->engine.engine_time = snmpd_engine.engine_time;
643 		}
644 	} else if (pdu->user.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 = SNMPD_INPUT_FAILED;
648 	}
649 
650 	if ((code = snmp_pdu_auth_access(pdu, ip)) != SNMP_CODE_OK)
651 		ret = SNMPD_INPUT_FAILED;
652 
653 	return (ret);
654 }
655 
656 /*
657  * Will return only _OK or _FAILED
658  */
659 enum snmpd_input_err
snmp_input_finish(struct snmp_pdu * pdu,const u_char * rcvbuf,size_t rcvlen,u_char * sndbuf,size_t * sndlen,const char * source,enum snmpd_input_err ierr,int32_t ivar,void * data)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
trans_insert_port(struct transport * t,struct tport * port)766 trans_insert_port(struct transport *t, struct tport *port)
767 {
768 	struct tport *p;
769 
770 	port->transport = t;
771 	TAILQ_FOREACH(p, &t->table, link) {
772 		if (asn_compare_oid(&p->index, &port->index) > 0) {
773 			TAILQ_INSERT_BEFORE(p, port, link);
774 			return;
775 		}
776 	}
777 	TAILQ_INSERT_TAIL(&t->table, port, link);
778 }
779 
780 /*
781  * Remove a port from a transport's list
782  */
783 void
trans_remove_port(struct tport * port)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 *
trans_find_port(struct transport * t,const struct asn_oid * idx,u_int sub)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 *
trans_next_port(struct transport * t,const struct asn_oid * idx,u_int sub)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 *
trans_first_port(struct transport * t)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 *
trans_iter_port(struct transport * t,int (* func)(struct tport *,intptr_t),intptr_t arg)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
trans_register(const struct transport_def * def,struct transport ** pp)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
trans_unregister(struct transport * t)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
input(int fd,int mask __unused,void * uap)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
fd_suspend(void * p)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
fd_resume(void * p)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, RPOLL_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 *
fd_select(int fd,void (* func)(int,void *),void * udata,struct lmodule * mod)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
fd_deselect(void * p)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
fd_flush(struct lmodule * mod)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
snmp_input_consume(struct port_input * pi)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 /*
1030  * Input from a socket
1031  */
1032 int
snmpd_input(struct port_input * pi,struct tport * tport)1033 snmpd_input(struct port_input *pi, struct tport *tport)
1034 {
1035 	u_char *sndbuf;
1036 	size_t sndlen;
1037 	struct snmp_pdu pdu;
1038 	enum snmpd_input_err ierr, ferr;
1039 	enum snmpd_proxy_err perr;
1040 	ssize_t ret, slen;
1041 	int32_t vi;
1042 #ifdef USE_TCPWRAPPERS
1043 	char client[INET6_ADDRSTRLEN];
1044 #endif
1045 
1046 	ret = tport->transport->vtab->recv(tport, pi);
1047 	if (ret == -1)
1048 		return (-1);
1049 
1050 #ifdef USE_TCPWRAPPERS
1051 	/*
1052 	 * In case of AF_INET{6} peer, do hosts_access(5) check.
1053 	 */
1054 	if (pi->peer->sa_family != AF_LOCAL &&
1055 	    inet_ntop(pi->peer->sa_family,
1056 	    &((const struct sockaddr_in *)(const void *)pi->peer)->sin_addr,
1057 	    client, sizeof(client)) != NULL) {
1058 		request_set(&req, RQ_CLIENT_ADDR, client, 0);
1059 		if (hosts_access(&req) == 0) {
1060 			syslog(LOG_ERR, "refused connection from %.500s",
1061 			    eval_client(&req));
1062 			return (-1);
1063 		}
1064 	} else if (pi->peer->sa_family != AF_LOCAL)
1065 		syslog(LOG_ERR, "inet_ntop(): %m");
1066 #endif
1067 
1068 	/*
1069 	 * Handle input
1070 	 */
1071 	ierr = snmp_input_start(pi->buf, pi->length, "SNMP", &pdu, &vi,
1072 	    &pi->consumed);
1073 	if (ierr == SNMPD_INPUT_TRUNC) {
1074 		/* need more bytes. This is ok only for streaming transports.
1075 		 * but only if we have not reached bufsiz yet. */
1076 		if (pi->stream) {
1077 			if (pi->length == buf_size(0)) {
1078 				snmpd_stats.silentDrops++;
1079 				return (-1);
1080 			}
1081 			return (0);
1082 		}
1083 		snmpd_stats.silentDrops++;
1084 		return (-1);
1085 	}
1086 
1087 	/* can't check for bad SET pdus here, because a proxy may have to
1088 	 * check the access first. We don't want to return an error response
1089 	 * to a proxy PDU with a wrong community */
1090 	if (ierr == SNMPD_INPUT_FAILED) {
1091 		/* for streaming transports this is fatal */
1092 		if (pi->stream)
1093 			return (-1);
1094 		snmp_input_consume(pi);
1095 		return (0);
1096 	}
1097 	if (ierr == SNMPD_INPUT_BAD_COMM) {
1098 		snmp_input_consume(pi);
1099 		return (0);
1100 	}
1101 
1102 	/*
1103 	 * If that is a module community and the module has a proxy function,
1104 	 * the hand it over to the module.
1105 	 */
1106 	if (comm != NULL && comm->owner != NULL &&
1107 	    comm->owner->config->proxy != NULL) {
1108 		perr = (*comm->owner->config->proxy)(&pdu, tport->transport,
1109 		    &tport->index, pi->peer, pi->peerlen, ierr, vi,
1110 		    !pi->cred || pi->priv);
1111 
1112 		switch (perr) {
1113 
1114 		  case SNMPD_PROXY_OK:
1115 			snmp_input_consume(pi);
1116 			return (0);
1117 
1118 		  case SNMPD_PROXY_REJ:
1119 			break;
1120 
1121 		  case SNMPD_PROXY_DROP:
1122 			snmp_input_consume(pi);
1123 			snmp_pdu_free(&pdu);
1124 			snmpd_stats.proxyDrops++;
1125 			return (0);
1126 
1127 		  case SNMPD_PROXY_BADCOMM:
1128 			snmp_input_consume(pi);
1129 			snmp_pdu_free(&pdu);
1130 			snmpd_stats.inBadCommunityNames++;
1131 			if (snmpd.auth_traps)
1132 				snmp_send_trap(&oid_authenticationFailure,
1133 				    (struct snmp_value *)NULL);
1134 			return (0);
1135 
1136 		  case SNMPD_PROXY_BADCOMMUSE:
1137 			snmp_input_consume(pi);
1138 			snmp_pdu_free(&pdu);
1139 			snmpd_stats.inBadCommunityUses++;
1140 			if (snmpd.auth_traps)
1141 				snmp_send_trap(&oid_authenticationFailure,
1142 				    (struct snmp_value *)NULL);
1143 			return (0);
1144 		}
1145 	}
1146 
1147 	/*
1148 	 * Check type
1149 	 */
1150 	if (pdu.type == SNMP_PDU_RESPONSE ||
1151 	    pdu.type == SNMP_PDU_TRAP ||
1152 	    pdu.type == SNMP_PDU_TRAP2) {
1153 		snmpd_stats.silentDrops++;
1154 		snmpd_stats.inBadPduTypes++;
1155 		snmp_pdu_free(&pdu);
1156 		snmp_input_consume(pi);
1157 		return (0);
1158 	}
1159 
1160 	/*
1161 	 * Check community
1162 	 */
1163 	if (pdu.version < SNMP_V3 &&
1164 	    ((pi->cred && !pi->priv && pdu.type == SNMP_PDU_SET) ||
1165 	    (comm != NULL && comm->private != COMM_WRITE &&
1166             (pdu.type == SNMP_PDU_SET || comm->private != COMM_READ)))) {
1167 		snmpd_stats.inBadCommunityUses++;
1168 		snmp_pdu_free(&pdu);
1169 		snmp_input_consume(pi);
1170 		if (snmpd.auth_traps)
1171 			snmp_send_trap(&oid_authenticationFailure,
1172 			    (struct snmp_value *)NULL);
1173 		return (0);
1174 	}
1175 
1176 	/*
1177 	 * Execute it.
1178 	 */
1179 	if ((sndbuf = buf_alloc(1)) == NULL) {
1180 		snmpd_stats.silentDrops++;
1181 		snmp_pdu_free(&pdu);
1182 		snmp_input_consume(pi);
1183 		return (0);
1184 	}
1185 	ferr = snmp_input_finish(&pdu, pi->buf, pi->length,
1186 	    sndbuf, &sndlen, "SNMP", ierr, vi, NULL);
1187 
1188 	if (ferr == SNMPD_INPUT_OK) {
1189 		if (tport->transport->vtab->send != NULL)
1190 			slen = tport->transport->vtab->send(tport, sndbuf,
1191 			    sndlen, pi->peer, pi->peerlen);
1192 		else
1193 			slen = tport->transport->vtab->send2(tport, sndbuf,
1194 			    sndlen, pi);
1195 		if (slen == -1)
1196 			syslog(LOG_ERR, "send*: %m");
1197 		else if ((size_t)slen != sndlen)
1198 			syslog(LOG_ERR, "send*: short write %zu/%zu", sndlen,
1199 			    (size_t)slen);
1200 	}
1201 
1202 	snmp_pdu_free(&pdu);
1203 	free(sndbuf);
1204 	snmp_input_consume(pi);
1205 
1206 	return (0);
1207 }
1208 
1209 /*
1210  * Send a PDU to a given port. If this is a multi-socket port, use the
1211  * first socket.
1212  */
1213 void
snmp_send_port(void * targ,const struct asn_oid * port,struct snmp_pdu * pdu,const struct sockaddr * addr,socklen_t addrlen)1214 snmp_send_port(void *targ, const struct asn_oid *port, struct snmp_pdu *pdu,
1215     const struct sockaddr *addr, socklen_t addrlen)
1216 {
1217 	struct transport *trans = targ;
1218 	struct tport *tp;
1219 	u_char *sndbuf;
1220 	size_t sndlen;
1221 	ssize_t len;
1222 
1223 	TAILQ_FOREACH(tp, &trans->table, link)
1224 		if (asn_compare_oid(port, &tp->index) == 0)
1225 			break;
1226 	if (tp == 0)
1227 		return;
1228 
1229 	if ((sndbuf = buf_alloc(1)) == NULL)
1230 		return;
1231 
1232 	snmp_output(pdu, sndbuf, &sndlen, "SNMP PROXY");
1233 
1234 	if (trans->vtab->send != NULL)
1235 		len = trans->vtab->send(tp, sndbuf, sndlen, addr, addrlen);
1236 	else
1237 		len = trans->vtab->send2(tp, sndbuf, sndlen, NULL);
1238 
1239 	if (len == -1)
1240 		syslog(LOG_ERR, "sendto: %m");
1241 	else if ((size_t)len != sndlen)
1242 		syslog(LOG_ERR, "sendto: short write %zu/%zu",
1243 		    sndlen, (size_t)len);
1244 
1245 	free(sndbuf);
1246 }
1247 
1248 
1249 /*
1250  * Close an input source
1251  *
1252  * \param pi	input instance
1253  */
1254 void
snmpd_input_close(struct port_input * pi)1255 snmpd_input_close(struct port_input *pi)
1256 {
1257 	if (pi->id != NULL) {
1258 		fd_deselect(pi->id);
1259 		pi->id = NULL;
1260 	}
1261 	if (pi->fd >= 0) {
1262 		(void)close(pi->fd);
1263 		pi->fd = -1;
1264 	}
1265 	if (pi->buf != NULL) {
1266 		free(pi->buf);
1267 		pi->buf = NULL;
1268 	}
1269 }
1270 
1271 /*
1272  * Initialize an input source.
1273  *
1274  * \param pi	input instance
1275  */
1276 void
snmpd_input_init(struct port_input * pi)1277 snmpd_input_init(struct port_input *pi)
1278 {
1279 	pi->id = NULL;
1280 	pi->fd = -1;
1281 	pi->buf = NULL;
1282 }
1283 
1284 /*
1285  * Dump internal state.
1286  */
1287 #ifdef USE_LIBBEGEMOT
1288 static void
info_func(void)1289 info_func(void)
1290 #else
1291 static void
1292 info_func(evContext ctx __unused, void *uap __unused, const void *tag __unused)
1293 #endif
1294 {
1295 	struct lmodule *m;
1296 	u_int i;
1297 	char buf[10000];
1298 
1299 	syslog(LOG_DEBUG, "Dump of SNMPd %lu\n", (u_long)getpid());
1300 	for (i = 0; i < tree_size; i++) {
1301 		switch (tree[i].type) {
1302 
1303 		  case SNMP_NODE_LEAF:
1304 			sprintf(buf, "LEAF: %s %s", tree[i].name,
1305 			    asn_oid2str(&tree[i].oid));
1306 			break;
1307 
1308 		  case SNMP_NODE_COLUMN:
1309 			sprintf(buf, "COL: %s %s", tree[i].name,
1310 			    asn_oid2str(&tree[i].oid));
1311 			break;
1312 		}
1313 		syslog(LOG_DEBUG, "%s", buf);
1314 	}
1315 
1316 	TAILQ_FOREACH(m, &lmodules, link)
1317 		if (m->config->dump)
1318 			(*m->config->dump)();
1319 }
1320 
1321 /*
1322  * Re-read configuration
1323  */
1324 #ifdef USE_LIBBEGEMOT
1325 static void
config_func(void)1326 config_func(void)
1327 #else
1328 static void
1329 config_func(evContext ctx __unused, void *uap __unused,
1330     const void *tag __unused)
1331 #endif
1332 {
1333 	struct lmodule *m;
1334 
1335 	if (read_config(config_file, NULL)) {
1336 		syslog(LOG_ERR, "error reading config file '%s'", config_file);
1337 		return;
1338 	}
1339 	TAILQ_FOREACH(m, &lmodules, link)
1340 		if (m->config->config)
1341 			(*m->config->config)();
1342 }
1343 
1344 /*
1345  * On USR1 dump actual configuration.
1346  */
1347 static void
onusr1(int s __unused)1348 onusr1(int s __unused)
1349 {
1350 
1351 	work |= WORK_DOINFO;
1352 }
1353 static void
onhup(int s __unused)1354 onhup(int s __unused)
1355 {
1356 
1357 	work |= WORK_RECONFIG;
1358 }
1359 
1360 static void
onterm(int s __unused)1361 onterm(int s __unused)
1362 {
1363 
1364 	/* allow clean-up */
1365 	exit(0);
1366 }
1367 
1368 static void
init_sigs(void)1369 init_sigs(void)
1370 {
1371 	struct sigaction sa;
1372 
1373 	sa.sa_handler = onusr1;
1374 	sa.sa_flags = SA_RESTART;
1375 	sigemptyset(&sa.sa_mask);
1376 	if (sigaction(SIGUSR1, &sa, NULL)) {
1377 		syslog(LOG_ERR, "sigaction: %m");
1378 		exit(1);
1379 	}
1380 
1381 	sa.sa_handler = onhup;
1382 	if (sigaction(SIGHUP, &sa, NULL)) {
1383 		syslog(LOG_ERR, "sigaction: %m");
1384 		exit(1);
1385 	}
1386 
1387 	sa.sa_handler = onterm;
1388 	sa.sa_flags = 0;
1389 	sigemptyset(&sa.sa_mask);
1390 	if (sigaction(SIGTERM, &sa, NULL)) {
1391 		syslog(LOG_ERR, "sigaction: %m");
1392 		exit(1);
1393 	}
1394 	if (sigaction(SIGINT, &sa, NULL)) {
1395 		syslog(LOG_ERR, "sigaction: %m");
1396 		exit(1);
1397 	}
1398 }
1399 
1400 static void
block_sigs(void)1401 block_sigs(void)
1402 {
1403 	sigset_t set;
1404 
1405 	sigfillset(&set);
1406 	if (sigprocmask(SIG_BLOCK, &set, &blocked_sigs) == -1) {
1407 		syslog(LOG_ERR, "SIG_BLOCK: %m");
1408 		exit(1);
1409 	}
1410 }
1411 static void
unblock_sigs(void)1412 unblock_sigs(void)
1413 {
1414 	if (sigprocmask(SIG_SETMASK, &blocked_sigs, NULL) == -1) {
1415 		syslog(LOG_ERR, "SIG_SETMASK: %m");
1416 		exit(1);
1417 	}
1418 }
1419 
1420 /*
1421  * Shut down
1422  */
1423 static void
term(void)1424 term(void)
1425 {
1426 	(void)unlink(pid_file);
1427 }
1428 
1429 static void
trans_stop(void)1430 trans_stop(void)
1431 {
1432 	struct transport *t;
1433 
1434 	TAILQ_FOREACH(t, &transport_list, link)
1435 		(void)t->vtab->stop(1);
1436 }
1437 
1438 /*
1439  * Define a macro from the command line
1440  */
1441 static void
do_macro(char * arg)1442 do_macro(char *arg)
1443 {
1444 	char *eq;
1445 	int err;
1446 
1447 	if ((eq = strchr(arg, '=')) == NULL)
1448 		err = define_macro(arg, "");
1449 	else {
1450 		*eq++ = '\0';
1451 		err = define_macro(arg, eq);
1452 	}
1453 	if (err == -1) {
1454 		syslog(LOG_ERR, "cannot save macro: %m");
1455 		exit(1);
1456 	}
1457 }
1458 
1459 /*
1460  * Re-implement getsubopt from scratch, because the second argument is broken
1461  * and will not compile with WARNS=5.
1462  */
1463 static int
getsubopt1(char ** arg,const char * const * options,char ** valp,char ** optp)1464 getsubopt1(char **arg, const char *const *options, char **valp, char **optp)
1465 {
1466 	static const char *const delim = ",\t ";
1467 	u_int i;
1468 	char *ptr;
1469 
1470 	*optp = NULL;
1471 
1472 	/* skip leading junk */
1473 	for (ptr = *arg; *ptr != '\0'; ptr++)
1474 		if (strchr(delim, *ptr) == NULL)
1475 			break;
1476 	if (*ptr == '\0') {
1477 		*arg = ptr;
1478 		return (-1);
1479 	}
1480 	*optp = ptr;
1481 
1482 	/* find the end of the option */
1483 	while (*++ptr != '\0')
1484 		if (strchr(delim, *ptr) != NULL || *ptr == '=')
1485 			break;
1486 
1487 	if (*ptr != '\0') {
1488 		if (*ptr == '=') {
1489 			*ptr++ = '\0';
1490 			*valp = ptr;
1491 			while (*ptr != '\0' && strchr(delim, *ptr) == NULL)
1492 				ptr++;
1493 			if (*ptr != '\0')
1494 				*ptr++ = '\0';
1495 		} else
1496 			*ptr++ = '\0';
1497 	}
1498 
1499 	*arg = ptr;
1500 
1501 	for (i = 0; *options != NULL; options++, i++)
1502 		if (strcmp(*optp, *options) == 0)
1503 			return (i);
1504 	return (-1);
1505 }
1506 
1507 int
main(int argc,char * argv[])1508 main(int argc, char *argv[])
1509 {
1510 	int opt;
1511 	FILE *fp;
1512 	int background = 1;
1513 	struct tport *p;
1514 	const char *prefix = "snmpd";
1515 	struct lmodule *m;
1516 	char *value = NULL, *option; /* XXX */
1517 	struct transport *t;
1518 
1519 #define DBG_DUMP	0
1520 #define DBG_EVENTS	1
1521 #define DBG_TRACE	2
1522 	static const char *const debug_opts[] = {
1523 		"dump",
1524 		"events",
1525 		"trace",
1526 		NULL
1527 	};
1528 
1529 	snmp_printf = snmp_printf_func;
1530 	snmp_error = snmp_error_func;
1531 	snmp_debug = snmp_debug_func;
1532 	asn_error = asn_error_func;
1533 
1534 	while ((opt = getopt(argc, argv, "c:dD:e:hI:l:m:p:")) != EOF)
1535 		switch (opt) {
1536 
1537 		  case 'c':
1538 			strlcpy(config_file, optarg, sizeof(config_file));
1539 			break;
1540 
1541 		  case 'd':
1542 			background = 0;
1543 			break;
1544 
1545 		  case 'D':
1546 			while (*optarg) {
1547 				switch (getsubopt1(&optarg, debug_opts,
1548 				    &value, &option)) {
1549 
1550 				  case DBG_DUMP:
1551 					debug.dump_pdus = 1;
1552 					break;
1553 
1554 				  case DBG_EVENTS:
1555 					debug.evdebug++;
1556 					break;
1557 
1558 				  case DBG_TRACE:
1559 					if (value == NULL)
1560 						syslog(LOG_ERR,
1561 						    "no value for 'trace'");
1562 					else
1563 						snmp_trace = strtoul(value,
1564 						    NULL, 0);
1565 					break;
1566 
1567 				  case -1:
1568 					if (suboptarg)
1569 						syslog(LOG_ERR,
1570 						    "unknown debug flag '%s'",
1571 						    option);
1572 					else
1573 						syslog(LOG_ERR,
1574 						    "missing debug flag");
1575 					break;
1576 				}
1577 			}
1578 			break;
1579 
1580 		  case 'e':
1581 			strlcpy(engine_file, optarg, sizeof(engine_file));
1582 			break;
1583 		  case 'h':
1584 			fprintf(stderr, "%s", usgtxt);
1585 			exit(0);
1586 
1587 		  case 'I':
1588 			syspath = optarg;
1589 			break;
1590 
1591 		  case 'l':
1592 			prefix = optarg;
1593 			break;
1594 
1595 		  case 'm':
1596 			do_macro(optarg);
1597 			break;
1598 
1599 		  case 'p':
1600 			strlcpy(pid_file, optarg, sizeof(pid_file));
1601 			break;
1602 		}
1603 
1604 	openlog(prefix, LOG_PID | (background ? 0 : LOG_PERROR), LOG_USER);
1605 	setlogmask(LOG_UPTO(debug.logpri - 1));
1606 
1607 	if (background && daemon(0, 0) < 0) {
1608 		syslog(LOG_ERR, "daemon: %m");
1609 		exit(1);
1610 	}
1611 
1612 	argc -= optind;
1613 	argv += optind;
1614 
1615 	progargs = argv;
1616 	nprogargs = argc;
1617 
1618 	snmp_serial_no = arc4random();
1619 
1620 #ifdef USE_TCPWRAPPERS
1621 	/*
1622 	 * Initialize hosts_access(3) handler.
1623 	 */
1624 	request_init(&req, RQ_DAEMON, "snmpd", 0);
1625 	sock_methods(&req);
1626 #endif
1627 
1628 	/*
1629 	 * Initialize the tree.
1630 	 */
1631 	if ((tree = malloc(sizeof(struct snmp_node) * CTREE_SIZE)) == NULL) {
1632 		syslog(LOG_ERR, "%m");
1633 		exit(1);
1634 	}
1635 	memcpy(tree, ctree, sizeof(struct snmp_node) * CTREE_SIZE);
1636 	tree_size = CTREE_SIZE;
1637 
1638 	/*
1639 	 * Get standard communities
1640 	 */
1641 	comm_define(COMM_READ, "SNMP read", NULL, NULL);
1642 	comm_define(COMM_WRITE, "SNMP write", NULL, NULL);
1643 	community = COMM_INITIALIZE;
1644 
1645 	trap_reqid = reqid_allocate(512, NULL);
1646 
1647 	if (config_file[0] == '\0')
1648 		snprintf(config_file, sizeof(config_file), PATH_CONFIG, prefix);
1649 
1650 	init_actvals();
1651 	init_snmpd_engine();
1652 
1653 	this_tick = get_ticks();
1654 	start_tick = this_tick;
1655 
1656 	/* start transports */
1657 	if (atexit(trans_stop) == -1) {
1658 		syslog(LOG_ERR, "atexit failed: %m");
1659 		exit(1);
1660 	}
1661 	if (udp_trans.start() != SNMP_ERR_NOERROR)
1662 		syslog(LOG_WARNING, "cannot start UDP transport");
1663 	if (lsock_trans.start() != SNMP_ERR_NOERROR)
1664 		syslog(LOG_WARNING, "cannot start LSOCK transport");
1665 	if (inet_trans.start() != SNMP_ERR_NOERROR)
1666 		syslog(LOG_WARNING, "cannot start INET transport");
1667 
1668 #ifdef USE_LIBBEGEMOT
1669 	if (debug.evdebug > 0)
1670 		rpoll_trace = 1;
1671 #else
1672 	if (evCreate(&evctx)) {
1673 		syslog(LOG_ERR, "evCreate: %m");
1674 		exit(1);
1675 	}
1676 	if (debug.evdebug > 0)
1677 		evSetDebug(evctx, 10, stderr);
1678 #endif
1679 
1680 	if (engine_file[0] == '\0')
1681 		snprintf(engine_file, sizeof(engine_file), PATH_ENGINE, prefix);
1682 
1683 	if (read_config(config_file, NULL)) {
1684 		syslog(LOG_ERR, "error in config file");
1685 		exit(1);
1686 	}
1687 
1688 	TAILQ_FOREACH(t, &transport_list, link)
1689 		TAILQ_FOREACH(p, &t->table, link)
1690 			t->vtab->init_port(p);
1691 
1692 	init_sigs();
1693 
1694 	if (pid_file[0] == '\0')
1695 		snprintf(pid_file, sizeof(pid_file), PATH_PID, prefix);
1696 
1697 	if ((fp = fopen(pid_file, "w")) != NULL) {
1698 		fprintf(fp, "%u", getpid());
1699 		fclose(fp);
1700 		if (atexit(term) == -1) {
1701 			syslog(LOG_ERR, "atexit failed: %m");
1702 			(void)remove(pid_file);
1703 			exit(0);
1704 		}
1705 	}
1706 
1707 	if (or_register(&oid_snmpMIB, "The MIB module for SNMPv2 entities.",
1708 	    NULL) == 0) {
1709 		syslog(LOG_ERR, "cannot register SNMPv2 MIB");
1710 		exit(1);
1711 	}
1712 	if (or_register(&oid_begemotSnmpd, "The MIB module for the Begemot SNMPd.",
1713 	    NULL) == 0) {
1714 		syslog(LOG_ERR, "cannot register begemotSnmpd MIB");
1715 		exit(1);
1716 	}
1717 
1718 	while ((m = TAILQ_FIRST(&modules_start)) != NULL) {
1719 		m->flags &= ~LM_ONSTARTLIST;
1720 		TAILQ_REMOVE(&modules_start, m, start);
1721 		lm_start(m);
1722 	}
1723 
1724 	snmp_send_trap(&oid_coldStart, (struct snmp_value *)NULL);
1725 
1726 	for (;;) {
1727 #ifndef USE_LIBBEGEMOT
1728 		evEvent event;
1729 #endif
1730 		struct lmodule *mod;
1731 
1732 		TAILQ_FOREACH(mod, &lmodules, link)
1733 			if (mod->config->idle != NULL)
1734 				(*mod->config->idle)();
1735 
1736 #ifndef USE_LIBBEGEMOT
1737 		if (evGetNext(evctx, &event, EV_WAIT) == 0) {
1738 			if (evDispatch(evctx, event))
1739 				syslog(LOG_ERR, "evDispatch: %m");
1740 		} else if (errno != EINTR) {
1741 			syslog(LOG_ERR, "evGetNext: %m");
1742 			exit(1);
1743 		}
1744 #else
1745 		poll_dispatch(1);
1746 #endif
1747 
1748 		if (work != 0) {
1749 			block_sigs();
1750 			if (work & WORK_DOINFO) {
1751 #ifdef USE_LIBBEGEMOT
1752 				info_func();
1753 #else
1754 				if (evWaitFor(evctx, &work, info_func,
1755 				    NULL, NULL) == -1) {
1756 					syslog(LOG_ERR, "evWaitFor: %m");
1757 					exit(1);
1758 				}
1759 #endif
1760 			}
1761 			if (work & WORK_RECONFIG) {
1762 #ifdef USE_LIBBEGEMOT
1763 				config_func();
1764 #else
1765 				if (evWaitFor(evctx, &work, config_func,
1766 				    NULL, NULL) == -1) {
1767 					syslog(LOG_ERR, "evWaitFor: %m");
1768 					exit(1);
1769 				}
1770 #endif
1771 			}
1772 			work = 0;
1773 			unblock_sigs();
1774 #ifndef USE_LIBBEGEMOT
1775 			if (evDo(evctx, &work) == -1) {
1776 				syslog(LOG_ERR, "evDo: %m");
1777 				exit(1);
1778 			}
1779 #endif
1780 		}
1781 	}
1782 
1783 	return (0);
1784 }
1785 
1786 uint64_t
get_ticks(void)1787 get_ticks(void)
1788 {
1789 	struct timeval tv;
1790 	uint64_t ret;
1791 
1792 	if (gettimeofday(&tv, NULL))
1793 		abort();
1794 	ret = tv.tv_sec * 100ULL + tv.tv_usec / 10000ULL;
1795 	return (ret);
1796 }
1797 
1798 /*
1799  * Timer support
1800  */
1801 
1802 /*
1803  * Trampoline for the non-repeatable timers.
1804  */
1805 #ifdef USE_LIBBEGEMOT
1806 static void
tfunc(int tid __unused,void * uap)1807 tfunc(int tid __unused, void *uap)
1808 #else
1809 static void
1810 tfunc(evContext ctx __unused, void *uap, struct timespec due __unused,
1811 	struct timespec inter __unused)
1812 #endif
1813 {
1814 	struct timer *tp = uap;
1815 
1816 	LIST_REMOVE(tp, link);
1817 	tp->func(tp->udata);
1818 	free(tp);
1819 }
1820 
1821 /*
1822  * Trampoline for the repeatable timers.
1823  */
1824 #ifdef USE_LIBBEGEMOT
1825 static void
trfunc(int tid __unused,void * uap)1826 trfunc(int tid __unused, void *uap)
1827 #else
1828 static void
1829 trfunc(evContext ctx __unused, void *uap, struct timespec due __unused,
1830 	struct timespec inter __unused)
1831 #endif
1832 {
1833 	struct timer *tp = uap;
1834 
1835 	tp->func(tp->udata);
1836 }
1837 
1838 /*
1839  * Start a one-shot timer
1840  */
1841 void *
timer_start(u_int ticks,void (* func)(void *),void * udata,struct lmodule * mod)1842 timer_start(u_int ticks, void (*func)(void *), void *udata, struct lmodule *mod)
1843 {
1844 	struct timer *tp;
1845 #ifndef USE_LIBBEGEMOT
1846 	struct timespec due;
1847 #endif
1848 
1849 	if ((tp = malloc(sizeof(struct timer))) == NULL) {
1850 		syslog(LOG_CRIT, "out of memory for timer");
1851 		exit(1);
1852 	}
1853 
1854 #ifndef USE_LIBBEGEMOT
1855 	due = evAddTime(evNowTime(),
1856 	    evConsTime(ticks / 100, (ticks % 100) * 10000));
1857 #endif
1858 
1859 	tp->udata = udata;
1860 	tp->owner = mod;
1861 	tp->func = func;
1862 
1863 	LIST_INSERT_HEAD(&timer_list, tp, link);
1864 
1865 #ifdef USE_LIBBEGEMOT
1866 	if ((tp->id = poll_start_timer(ticks * 10, 0, tfunc, tp)) < 0) {
1867 		syslog(LOG_ERR, "cannot set timer: %m");
1868 		exit(1);
1869 	}
1870 #else
1871 	if (evSetTimer(evctx, tfunc, tp, due, evConsTime(0, 0), &tp->id)
1872 	    == -1) {
1873 		syslog(LOG_ERR, "cannot set timer: %m");
1874 		exit(1);
1875 	}
1876 #endif
1877 	return (tp);
1878 }
1879 
1880 /*
1881  * Start a repeatable timer. When used with USE_LIBBEGEMOT the first argument
1882  * is currently ignored and the initial number of ticks is set to the
1883  * repeat number of ticks.
1884  */
1885 void *
timer_start_repeat(u_int ticks __unused,u_int repeat_ticks,void (* func)(void *),void * udata,struct lmodule * mod)1886 timer_start_repeat(u_int ticks __unused, u_int repeat_ticks,
1887     void (*func)(void *), void *udata, struct lmodule *mod)
1888 {
1889 	struct timer *tp;
1890 #ifndef USE_LIBBEGEMOT
1891 	struct timespec due;
1892 	struct timespec inter;
1893 #endif
1894 
1895 	if ((tp = malloc(sizeof(struct timer))) == NULL) {
1896 		syslog(LOG_CRIT, "out of memory for timer");
1897 		exit(1);
1898 	}
1899 
1900 #ifndef USE_LIBBEGEMOT
1901 	due = evAddTime(evNowTime(),
1902 	    evConsTime(ticks / 100, (ticks % 100) * 10000));
1903 	inter = evConsTime(repeat_ticks / 100, (repeat_ticks % 100) * 10000);
1904 #endif
1905 
1906 	tp->udata = udata;
1907 	tp->owner = mod;
1908 	tp->func = func;
1909 
1910 	LIST_INSERT_HEAD(&timer_list, tp, link);
1911 
1912 #ifdef USE_LIBBEGEMOT
1913 	if ((tp->id = poll_start_timer(repeat_ticks * 10, 1, trfunc, tp)) < 0) {
1914 		syslog(LOG_ERR, "cannot set timer: %m");
1915 		exit(1);
1916 	}
1917 #else
1918 	if (evSetTimer(evctx, trfunc, tp, due, inter, &tp->id) == -1) {
1919 		syslog(LOG_ERR, "cannot set timer: %m");
1920 		exit(1);
1921 	}
1922 #endif
1923 	return (tp);
1924 }
1925 
1926 /*
1927  * Stop a timer.
1928  */
1929 void
timer_stop(void * p)1930 timer_stop(void *p)
1931 {
1932 	struct timer *tp = p;
1933 
1934 	LIST_REMOVE(tp, link);
1935 #ifdef USE_LIBBEGEMOT
1936 	poll_stop_timer(tp->id);
1937 #else
1938 	if (evClearTimer(evctx, tp->id) == -1) {
1939 		syslog(LOG_ERR, "cannot stop timer: %m");
1940 		exit(1);
1941 	}
1942 #endif
1943 	free(p);
1944 }
1945 
1946 static void
timer_flush(struct lmodule * mod)1947 timer_flush(struct lmodule *mod)
1948 {
1949 	struct timer *t, *t1;
1950 
1951 	t = LIST_FIRST(&timer_list);
1952 	while (t != NULL) {
1953 		t1 = LIST_NEXT(t, link);
1954 		if (t->owner == mod)
1955 			timer_stop(t);
1956 		t = t1;
1957 	}
1958 }
1959 
1960 static void
snmp_printf_func(const char * fmt,...)1961 snmp_printf_func(const char *fmt, ...)
1962 {
1963 	va_list ap;
1964 	static char *pend = NULL;
1965 	char *ret, *new;
1966 
1967 	va_start(ap, fmt);
1968 	vasprintf(&ret, fmt, ap);
1969 	va_end(ap);
1970 
1971 	if (ret == NULL)
1972 		return;
1973 	if (pend != NULL) {
1974 		if ((new = realloc(pend, strlen(pend) + strlen(ret) + 1))
1975 		    == NULL) {
1976 			free(ret);
1977 			return;
1978 		}
1979 		pend = new;
1980 		strcat(pend, ret);
1981 		free(ret);
1982 	} else
1983 		pend = ret;
1984 
1985 	while ((ret = strchr(pend, '\n')) != NULL) {
1986 		*ret = '\0';
1987 		syslog(LOG_DEBUG, "%s", pend);
1988 		if (strlen(ret + 1) == 0) {
1989 			free(pend);
1990 			pend = NULL;
1991 			break;
1992 		}
1993 		strcpy(pend, ret + 1);
1994 	}
1995 }
1996 
1997 static void
snmp_error_func(const char * err,...)1998 snmp_error_func(const char *err, ...)
1999 {
2000 	char errbuf[1000];
2001 	va_list ap;
2002 
2003 	if (!(snmp_trace & LOG_SNMP_ERRORS))
2004 		return;
2005 
2006 	va_start(ap, err);
2007 	snprintf(errbuf, sizeof(errbuf), "SNMP: ");
2008 	vsnprintf(errbuf + strlen(errbuf),
2009 	    sizeof(errbuf) - strlen(errbuf), err, ap);
2010 	va_end(ap);
2011 
2012 	syslog(LOG_ERR, "%s", errbuf);
2013 }
2014 
2015 static void
snmp_debug_func(const char * err,...)2016 snmp_debug_func(const char *err, ...)
2017 {
2018 	char errbuf[1000];
2019 	va_list ap;
2020 
2021 	va_start(ap, err);
2022 	snprintf(errbuf, sizeof(errbuf), "SNMP: ");
2023 	vsnprintf(errbuf+strlen(errbuf), sizeof(errbuf)-strlen(errbuf),
2024 	    err, ap);
2025 	va_end(ap);
2026 
2027 	syslog(LOG_DEBUG, "%s", errbuf);
2028 }
2029 
2030 static void
asn_error_func(const struct asn_buf * b,const char * err,...)2031 asn_error_func(const struct asn_buf *b, const char *err, ...)
2032 {
2033 	char errbuf[1000];
2034 	va_list ap;
2035 	u_int i;
2036 
2037 	if (!(snmp_trace & LOG_ASN1_ERRORS))
2038 		return;
2039 
2040 	va_start(ap, err);
2041 	snprintf(errbuf, sizeof(errbuf), "ASN.1: ");
2042 	vsnprintf(errbuf + strlen(errbuf),
2043 	    sizeof(errbuf) - strlen(errbuf), err, ap);
2044 	va_end(ap);
2045 
2046 	if (b != NULL) {
2047 		snprintf(errbuf + strlen(errbuf),
2048 		    sizeof(errbuf) - strlen(errbuf), " at");
2049 		for (i = 0; b->asn_len > i; i++)
2050 			snprintf(errbuf + strlen(errbuf),
2051 			    sizeof(errbuf) - strlen(errbuf),
2052 			    " %02x", b->asn_cptr[i]);
2053 	}
2054 
2055 	syslog(LOG_ERR, "%s", errbuf);
2056 }
2057 
2058 /*
2059  * Create a new community
2060  */
2061 struct community*
comm_define_ordered(u_int priv,const char * descr,struct asn_oid * idx,struct lmodule * owner,const char * str)2062 comm_define_ordered(u_int priv, const char *descr, struct asn_oid *idx,
2063     struct lmodule *owner, const char *str)
2064 {
2065 	struct community *c, *p;
2066 	u_int ncomm;
2067 
2068 	ncomm = idx->subs[idx->len - 1];
2069 
2070 	/* check that community doesn't already exist */
2071 	TAILQ_FOREACH(c, &community_list, link)
2072 		if (c->value == ncomm)
2073 			return (c);
2074 
2075 	if ((c = malloc(sizeof(struct community))) == NULL) {
2076 		syslog(LOG_ERR, "%s: %m", __func__);
2077 		return (NULL);
2078 	}
2079 	c->owner = owner;
2080 	c->value = ncomm;
2081 	c->descr = descr;
2082 	c->string = NULL;
2083 	c->private = priv;
2084 
2085 	if (str != NULL) {
2086 		if((c->string = malloc(strlen(str)+1)) == NULL) {
2087 			free(c);
2088 			return (NULL);
2089 		}
2090 		strcpy(c->string, str);
2091 	}
2092 	/*
2093 	 * Insert ordered
2094 	 */
2095 	c->index = *idx;
2096 	TAILQ_FOREACH(p, &community_list, link) {
2097 		if (asn_compare_oid(&p->index, &c->index) > 0) {
2098 			TAILQ_INSERT_BEFORE(p, c, link);
2099 			break;
2100 		}
2101 	}
2102 	if (p == NULL)
2103 		TAILQ_INSERT_TAIL(&community_list, c, link);
2104 	return (c);
2105 }
2106 
2107 u_int
comm_define(u_int priv,const char * descr,struct lmodule * owner,const char * str)2108 comm_define(u_int priv, const char *descr, struct lmodule *owner,
2109     const char *str)
2110 {
2111 	struct asn_oid idx, *p;
2112 	struct community *c;
2113 	u_int ncomm;
2114 
2115 	/* generate an identifier */
2116 	do {
2117 		if ((ncomm = next_community_index++) == UINT_MAX)
2118 			next_community_index = 1;
2119 		TAILQ_FOREACH(c, &community_list, link)
2120 			if (c->value == ncomm)
2121 				break;
2122 	} while (c != NULL);
2123 
2124 	/* make index */
2125 	if (owner != NULL)
2126 		p = &owner->index;
2127 	else {
2128 		p = &idx;
2129 		p->len = 1;
2130 		p->subs[0] = 0;
2131 	}
2132 	p->subs[p->len++] = ncomm;
2133 	c = comm_define_ordered(priv, descr, p, owner, str);
2134 	if (c == NULL)
2135 		return (0);
2136 	return (c->value);
2137 }
2138 
2139 const char *
comm_string(u_int ncomm)2140 comm_string(u_int ncomm)
2141 {
2142 	struct community *p;
2143 
2144 	TAILQ_FOREACH(p, &community_list, link)
2145 		if (p->value == ncomm)
2146 			return (p->string);
2147 	return (NULL);
2148 }
2149 
2150 /*
2151  * Delete all communities allocated by a module
2152  */
2153 static void
comm_flush(struct lmodule * mod)2154 comm_flush(struct lmodule *mod)
2155 {
2156 	struct community *p, *p1;
2157 
2158 	p = TAILQ_FIRST(&community_list);
2159 	while (p != NULL) {
2160 		p1 = TAILQ_NEXT(p, link);
2161 		if (p->owner == mod) {
2162 			free(p->string);
2163 			TAILQ_REMOVE(&community_list, p, link);
2164 			free(p);
2165 		}
2166 		p = p1;
2167 	}
2168 }
2169 
2170 /*
2171  * Request ID handling.
2172  *
2173  * Allocate a new range of request ids. Use a first fit algorithm.
2174  */
2175 u_int
reqid_allocate(int size,struct lmodule * mod)2176 reqid_allocate(int size, struct lmodule *mod)
2177 {
2178 	u_int type;
2179 	struct idrange *r, *r1;
2180 
2181 	if (size <= 0 || size > INT32_MAX) {
2182 		syslog(LOG_CRIT, "%s: size out of range: %d", __func__, size);
2183 		return (0);
2184 	}
2185 	/* allocate a type id */
2186 	do {
2187 		if ((type = next_idrange++) == UINT_MAX)
2188 			next_idrange = 1;
2189 		TAILQ_FOREACH(r, &idrange_list, link)
2190 			if (r->type == type)
2191 				break;
2192 	} while(r != NULL);
2193 
2194 	/* find a range */
2195 	if (TAILQ_EMPTY(&idrange_list))
2196 		r = NULL;
2197 	else {
2198 		r = TAILQ_FIRST(&idrange_list);
2199 		if (r->base < size) {
2200 			while((r1 = TAILQ_NEXT(r, link)) != NULL) {
2201 				if (r1->base - (r->base + r->size) >= size)
2202 					break;
2203 				r = r1;
2204 			}
2205 			r = r1;
2206 		}
2207 		if (r == NULL) {
2208 			r1 = TAILQ_LAST(&idrange_list, idrange_list);
2209 			if (INT32_MAX - size + 1 < r1->base + r1->size) {
2210 				syslog(LOG_ERR, "out of id ranges (%u)", size);
2211 				return (0);
2212 			}
2213 		}
2214 	}
2215 
2216 	/* allocate structure */
2217 	if ((r1 = malloc(sizeof(struct idrange))) == NULL) {
2218 		syslog(LOG_ERR, "%s: %m", __FUNCTION__);
2219 		return (0);
2220 	}
2221 
2222 	r1->type = type;
2223 	r1->size = size;
2224 	r1->owner = mod;
2225 	if (TAILQ_EMPTY(&idrange_list) || r == TAILQ_FIRST(&idrange_list)) {
2226 		r1->base = 0;
2227 		TAILQ_INSERT_HEAD(&idrange_list, r1, link);
2228 	} else if (r == NULL) {
2229 		r = TAILQ_LAST(&idrange_list, idrange_list);
2230 		r1->base = r->base + r->size;
2231 		TAILQ_INSERT_TAIL(&idrange_list, r1, link);
2232 	} else {
2233 		r = TAILQ_PREV(r, idrange_list, link);
2234 		r1->base = r->base + r->size;
2235 		TAILQ_INSERT_AFTER(&idrange_list, r, r1, link);
2236 	}
2237 	r1->next = r1->base;
2238 
2239 	return (type);
2240 }
2241 
2242 int32_t
reqid_next(u_int type)2243 reqid_next(u_int type)
2244 {
2245 	struct idrange *r;
2246 	int32_t id;
2247 
2248 	TAILQ_FOREACH(r, &idrange_list, link)
2249 		if (r->type == type)
2250 			break;
2251 	if (r == NULL) {
2252 		syslog(LOG_CRIT, "wrong idrange type");
2253 		abort();
2254 	}
2255 	if ((id = r->next++) == r->base + (r->size - 1))
2256 		r->next = r->base;
2257 	return (id);
2258 }
2259 
2260 int32_t
reqid_base(u_int type)2261 reqid_base(u_int type)
2262 {
2263 	struct idrange *r;
2264 
2265 	TAILQ_FOREACH(r, &idrange_list, link)
2266 		if (r->type == type)
2267 			return (r->base);
2268 	syslog(LOG_CRIT, "wrong idrange type");
2269 	abort();
2270 }
2271 
2272 u_int
reqid_type(int32_t reqid)2273 reqid_type(int32_t reqid)
2274 {
2275 	struct idrange *r;
2276 
2277 	TAILQ_FOREACH(r, &idrange_list, link)
2278 		if (reqid >= r->base && reqid <= r->base + (r->size - 1))
2279 			return (r->type);
2280 	return (0);
2281 }
2282 
2283 int
reqid_istype(int32_t reqid,u_int type)2284 reqid_istype(int32_t reqid, u_int type)
2285 {
2286 	return (reqid_type(reqid) == type);
2287 }
2288 
2289 /*
2290  * Delete all communities allocated by a module
2291  */
2292 static void
reqid_flush(struct lmodule * mod)2293 reqid_flush(struct lmodule *mod)
2294 {
2295 	struct idrange *p, *p1;
2296 
2297 	p = TAILQ_FIRST(&idrange_list);
2298 	while (p != NULL) {
2299 		p1 = TAILQ_NEXT(p, link);
2300 		if (p->owner == mod) {
2301 			TAILQ_REMOVE(&idrange_list, p, link);
2302 			free(p);
2303 		}
2304 		p = p1;
2305 	}
2306 }
2307 
2308 /*
2309  * Merge the given tree for the given module into the main tree.
2310  */
2311 static int
compare_node(const void * v1,const void * v2)2312 compare_node(const void *v1, const void *v2)
2313 {
2314 	const struct snmp_node *n1 = v1;
2315 	const struct snmp_node *n2 = v2;
2316 
2317 	return (asn_compare_oid(&n1->oid, &n2->oid));
2318 }
2319 static int
tree_merge(const struct snmp_node * ntree,u_int nsize,struct lmodule * mod)2320 tree_merge(const struct snmp_node *ntree, u_int nsize, struct lmodule *mod)
2321 {
2322 	struct snmp_node *xtree;
2323 	u_int i;
2324 
2325 	xtree = realloc(tree, sizeof(*tree) * (tree_size + nsize));
2326 	if (xtree == NULL) {
2327 		syslog(LOG_ERR, "tree_merge: %m");
2328 		return (-1);
2329 	}
2330 	tree = xtree;
2331 	memcpy(&tree[tree_size], ntree, sizeof(*tree) * nsize);
2332 
2333 	for (i = 0; i < nsize; i++)
2334 		tree[tree_size + i].tree_data = mod;
2335 
2336 	tree_size += nsize;
2337 
2338 	qsort(tree, tree_size, sizeof(tree[0]), compare_node);
2339 
2340 	return (0);
2341 }
2342 
2343 /*
2344  * Remove all nodes belonging to the loadable module
2345  */
2346 static void
tree_unmerge(struct lmodule * mod)2347 tree_unmerge(struct lmodule *mod)
2348 {
2349 	u_int s, d;
2350 
2351 	for(s = d = 0; s < tree_size; s++)
2352 		if (tree[s].tree_data != mod) {
2353 			if (s != d)
2354 				tree[d] = tree[s];
2355 			d++;
2356 		}
2357 	tree_size = d;
2358 }
2359 
2360 /*
2361  * Loadable modules
2362  */
2363 struct lmodule *
lm_load(const char * path,const char * section)2364 lm_load(const char *path, const char *section)
2365 {
2366 	struct lmodule *m;
2367 	int err;
2368 	int i;
2369 	char *av[MAX_MOD_ARGS + 1];
2370 	int ac;
2371 	u_int u;
2372 
2373 	if ((m = malloc(sizeof(*m))) == NULL) {
2374 		syslog(LOG_ERR, "lm_load: %m");
2375 		return (NULL);
2376 	}
2377 	m->handle = NULL;
2378 	m->flags = 0;
2379 	strlcpy(m->section, section, sizeof(m->section));
2380 
2381 	if ((m->path = strdup(path)) == NULL) {
2382 		syslog(LOG_ERR, "lm_load: %m");
2383 		goto err;
2384 	}
2385 
2386 	/*
2387 	 * Make index
2388 	 */
2389 	m->index.subs[0] = strlen(section);
2390 	m->index.len = m->index.subs[0] + 1;
2391 	for (u = 0; u < m->index.subs[0]; u++)
2392 		m->index.subs[u + 1] = section[u];
2393 
2394 	/*
2395 	 * Load the object file and locate the config structure
2396 	 */
2397 	if ((m->handle = dlopen(m->path, RTLD_NOW|RTLD_GLOBAL)) == NULL) {
2398 		syslog(LOG_ERR, "lm_load: open %s", dlerror());
2399 		goto err;
2400 	}
2401 
2402 	if ((m->config = dlsym(m->handle, "config")) == NULL) {
2403 		syslog(LOG_ERR, "lm_load: no 'config' symbol %s", dlerror());
2404 		goto err;
2405 	}
2406 
2407 	/*
2408 	 * Insert it into the right place
2409 	 */
2410 	INSERT_OBJECT_OID(m, &lmodules);
2411 
2412 	/* preserve order */
2413 	if (community == COMM_INITIALIZE) {
2414 		m->flags |= LM_ONSTARTLIST;
2415 		TAILQ_INSERT_TAIL(&modules_start, m, start);
2416 	}
2417 
2418 	/*
2419 	 * make the argument vector.
2420 	 */
2421 	ac = 0;
2422 	for (i = 0; i < nprogargs; i++) {
2423 		if (strlen(progargs[i]) >= strlen(section) + 1 &&
2424 		    strncmp(progargs[i], section, strlen(section)) == 0 &&
2425 		    progargs[i][strlen(section)] == ':') {
2426 			if (ac == MAX_MOD_ARGS) {
2427 				syslog(LOG_WARNING, "too many arguments for "
2428 				    "module '%s", section);
2429 				break;
2430 			}
2431 			av[ac++] = &progargs[i][strlen(section)+1];
2432 		}
2433 	}
2434 	av[ac] = NULL;
2435 
2436 	/*
2437 	 * Run the initialization function
2438 	 */
2439 	if ((err = (*m->config->init)(m, ac, av)) != 0) {
2440 		syslog(LOG_ERR, "lm_load: init failed: %d", err);
2441 		TAILQ_REMOVE(&lmodules, m, link);
2442 		goto err;
2443 	}
2444 
2445 	return (m);
2446 
2447   err:
2448 	if ((m->flags & LM_ONSTARTLIST) != 0)
2449 		TAILQ_REMOVE(&modules_start, m, start);
2450 	if (m->handle)
2451 		dlclose(m->handle);
2452 	free(m->path);
2453 	free(m);
2454 	return (NULL);
2455 }
2456 
2457 /*
2458  * Start a module
2459  */
2460 void
lm_start(struct lmodule * mod)2461 lm_start(struct lmodule *mod)
2462 {
2463 	const struct lmodule *m;
2464 
2465 	/*
2466 	 * Merge tree. If this fails, unload the module.
2467 	 */
2468 	if (tree_merge(mod->config->tree, mod->config->tree_size, mod)) {
2469 		lm_unload(mod);
2470 		return;
2471 	}
2472 
2473 	/*
2474 	 * Read configuration
2475 	 */
2476 	if (read_config(config_file, mod)) {
2477 		syslog(LOG_ERR, "error in config file");
2478 		lm_unload(mod);
2479 		return;
2480 	}
2481 	if (mod->config->start)
2482 		(*mod->config->start)();
2483 
2484 	mod->flags |= LM_STARTED;
2485 
2486 	/*
2487 	 * Inform other modules
2488 	 */
2489 	TAILQ_FOREACH(m, &lmodules, link)
2490 		if (m->config->loading)
2491 			(*m->config->loading)(mod, 1);
2492 }
2493 
2494 
2495 /*
2496  * Unload a module.
2497  */
2498 void
lm_unload(struct lmodule * m)2499 lm_unload(struct lmodule *m)
2500 {
2501 	int err;
2502 	const struct lmodule *mod;
2503 
2504 	TAILQ_REMOVE(&lmodules, m, link);
2505 	if (m->flags & LM_ONSTARTLIST)
2506 		TAILQ_REMOVE(&modules_start, m, start);
2507 	tree_unmerge(m);
2508 
2509 	if ((m->flags & LM_STARTED) && m->config->fini &&
2510 	    (err = (*m->config->fini)()) != 0)
2511 		syslog(LOG_WARNING, "lm_unload(%s): fini %d", m->section, err);
2512 
2513 	comm_flush(m);
2514 	reqid_flush(m);
2515 	timer_flush(m);
2516 	fd_flush(m);
2517 
2518 	dlclose(m->handle);
2519 	free(m->path);
2520 
2521 	/*
2522 	 * Inform other modules
2523 	 */
2524 	TAILQ_FOREACH(mod, &lmodules, link)
2525 		if (mod->config->loading)
2526 			(*mod->config->loading)(m, 0);
2527 
2528 	free(m);
2529 }
2530 
2531 /*
2532  * Register an object resource and return the index (or 0 on failures)
2533  */
2534 u_int
or_register(const struct asn_oid * or,const char * descr,struct lmodule * mod)2535 or_register(const struct asn_oid *or, const char *descr, struct lmodule *mod)
2536 {
2537 	struct objres *objres, *or1;
2538 	u_int idx;
2539 
2540 	/* find a free index */
2541 	idx = 1;
2542 	for (objres = TAILQ_FIRST(&objres_list);
2543 	     objres != NULL;
2544 	     objres = TAILQ_NEXT(objres, link)) {
2545 		if ((or1 = TAILQ_NEXT(objres, link)) == NULL ||
2546 		    or1->index > objres->index + 1) {
2547 			idx = objres->index + 1;
2548 			break;
2549 		}
2550 	}
2551 
2552 	if ((objres = malloc(sizeof(*objres))) == NULL)
2553 		return (0);
2554 
2555 	objres->index = idx;
2556 	objres->oid = *or;
2557 	strlcpy(objres->descr, descr, sizeof(objres->descr));
2558 	objres->uptime = (uint32_t)(get_ticks() - start_tick);
2559 	objres->module = mod;
2560 
2561 	INSERT_OBJECT_INT(objres, &objres_list);
2562 
2563 	systemg.or_last_change = objres->uptime;
2564 
2565 	return (idx);
2566 }
2567 
2568 void
or_unregister(u_int idx)2569 or_unregister(u_int idx)
2570 {
2571 	struct objres *objres;
2572 
2573 	TAILQ_FOREACH(objres, &objres_list, link)
2574 		if (objres->index == idx) {
2575 			TAILQ_REMOVE(&objres_list, objres, link);
2576 			free(objres);
2577 			return;
2578 		}
2579 }
2580 
2581 /*
2582  * RFC 3414 User-based Security Model support
2583  */
2584 
2585 struct snmpd_usmstat *
bsnmpd_get_usm_stats(void)2586 bsnmpd_get_usm_stats(void)
2587 {
2588 	return (&snmpd_usmstats);
2589 }
2590 
2591 void
bsnmpd_reset_usm_stats(void)2592 bsnmpd_reset_usm_stats(void)
2593 {
2594 	memset(&snmpd_usmstats, 0, sizeof(snmpd_usmstats));
2595 }
2596 
2597 struct usm_user *
usm_first_user(void)2598 usm_first_user(void)
2599 {
2600 	return (SLIST_FIRST(&usm_userlist));
2601 }
2602 
2603 struct usm_user *
usm_next_user(struct usm_user * uuser)2604 usm_next_user(struct usm_user *uuser)
2605 {
2606 	if (uuser == NULL)
2607 		return (NULL);
2608 
2609 	return (SLIST_NEXT(uuser, up));
2610 }
2611 
2612 struct usm_user *
usm_find_user(uint8_t * engine,uint32_t elen,char * uname)2613 usm_find_user(uint8_t *engine, uint32_t elen, char *uname)
2614 {
2615 	struct usm_user *uuser;
2616 
2617 	SLIST_FOREACH(uuser, &usm_userlist, up)
2618 		if (uuser->user_engine_len == elen &&
2619 		    memcmp(uuser->user_engine_id, engine, elen) == 0 &&
2620 		    strlen(uuser->suser.sec_name) == strlen(uname) &&
2621 		    strcmp(uuser->suser.sec_name, uname) == 0)
2622 			break;
2623 
2624 	return (uuser);
2625 }
2626 
2627 static int
usm_compare_user(struct usm_user * u1,struct usm_user * u2)2628 usm_compare_user(struct usm_user *u1, struct usm_user *u2)
2629 {
2630 	uint32_t i;
2631 
2632 	if (u1->user_engine_len < u2->user_engine_len)
2633 		return (-1);
2634 	if (u1->user_engine_len > u2->user_engine_len)
2635 		return (1);
2636 
2637 	for (i = 0; i < u1->user_engine_len; i++) {
2638 		if (u1->user_engine_id[i] < u2->user_engine_id[i])
2639 			return (-1);
2640 		if (u1->user_engine_id[i] > u2->user_engine_id[i])
2641 			return (1);
2642 	}
2643 
2644 	if (strlen(u1->suser.sec_name) < strlen(u2->suser.sec_name))
2645 		return (-1);
2646 	if (strlen(u1->suser.sec_name) > strlen(u2->suser.sec_name))
2647 		return (1);
2648 
2649 	for (i = 0; i < strlen(u1->suser.sec_name); i++) {
2650 		if (u1->suser.sec_name[i] < u2->suser.sec_name[i])
2651 			return (-1);
2652 		if (u1->suser.sec_name[i] > u2->suser.sec_name[i])
2653 			return (1);
2654 	}
2655 
2656 	return (0);
2657 }
2658 
2659 struct usm_user *
usm_new_user(uint8_t * eid,uint32_t elen,char * uname)2660 usm_new_user(uint8_t *eid, uint32_t elen, char *uname)
2661 {
2662 	int cmp;
2663 	struct usm_user *uuser, *temp, *prev;
2664 
2665 	for (uuser = usm_first_user(); uuser != NULL;
2666 	    (uuser = usm_next_user(uuser))) {
2667 		if (uuser->user_engine_len == elen &&
2668 		    strlen(uname) == strlen(uuser->suser.sec_name) &&
2669 		    strcmp(uname, uuser->suser.sec_name) == 0 &&
2670 		    memcmp(eid, uuser->user_engine_id, elen) == 0)
2671 			return (NULL);
2672 	}
2673 
2674 	if ((uuser = (struct usm_user *)malloc(sizeof(*uuser))) == NULL)
2675 		return (NULL);
2676 
2677 	memset(uuser, 0, sizeof(*uuser));
2678 	strlcpy(uuser->suser.sec_name, uname, SNMP_ADM_STR32_SIZ);
2679 	memcpy(uuser->user_engine_id, eid, elen);
2680 	uuser->user_engine_len = elen;
2681 
2682 	if ((prev = SLIST_FIRST(&usm_userlist)) == NULL ||
2683 	    usm_compare_user(uuser, prev) < 0) {
2684 		SLIST_INSERT_HEAD(&usm_userlist, uuser, up);
2685 		return (uuser);
2686 	}
2687 
2688 	SLIST_FOREACH(temp, &usm_userlist, up) {
2689 		if ((cmp = usm_compare_user(uuser, temp)) <= 0)
2690 			break;
2691 		prev = temp;
2692 	}
2693 
2694 	if (temp == NULL || cmp < 0)
2695 		SLIST_INSERT_AFTER(prev, uuser, up);
2696 	else if (cmp > 0)
2697 		SLIST_INSERT_AFTER(temp, uuser, up);
2698 	else {
2699 		syslog(LOG_ERR, "User %s exists", uuser->suser.sec_name);
2700 		free(uuser);
2701 		return (NULL);
2702 	}
2703 
2704 	return (uuser);
2705 }
2706 
2707 void
usm_delete_user(struct usm_user * uuser)2708 usm_delete_user(struct usm_user *uuser)
2709 {
2710 	SLIST_REMOVE(&usm_userlist, uuser, usm_user, up);
2711 	free(uuser);
2712 }
2713 
2714 void
usm_flush_users(void)2715 usm_flush_users(void)
2716 {
2717 	struct usm_user *uuser;
2718 
2719 	while ((uuser = SLIST_FIRST(&usm_userlist)) != NULL) {
2720 		SLIST_REMOVE_HEAD(&usm_userlist, up);
2721 		free(uuser);
2722 	}
2723 
2724 	SLIST_INIT(&usm_userlist);
2725 }
2726 
2727 /*
2728  * RFC 3415 View-based Access Control Model support
2729  */
2730 struct vacm_user *
vacm_first_user(void)2731 vacm_first_user(void)
2732 {
2733 	return (SLIST_FIRST(&vacm_userlist));
2734 }
2735 
2736 struct vacm_user *
vacm_next_user(struct vacm_user * vuser)2737 vacm_next_user(struct vacm_user *vuser)
2738 {
2739 	if (vuser == NULL)
2740 		return (NULL);
2741 
2742 	return (SLIST_NEXT(vuser, vvu));
2743 }
2744 
2745 static int
vacm_compare_user(struct vacm_user * v1,struct vacm_user * v2)2746 vacm_compare_user(struct vacm_user *v1, struct vacm_user *v2)
2747 {
2748 	uint32_t i;
2749 
2750 	if (v1->sec_model < v2->sec_model)
2751 		return (-1);
2752 	if (v1->sec_model > v2->sec_model)
2753 		return (1);
2754 
2755 	if (strlen(v1->secname) < strlen(v2->secname))
2756 		return (-1);
2757 	if (strlen(v1->secname) > strlen(v2->secname))
2758 		return (1);
2759 
2760 	for (i = 0; i < strlen(v1->secname); i++) {
2761 		if (v1->secname[i] < v2->secname[i])
2762 			return (-1);
2763 		if (v1->secname[i] > v2->secname[i])
2764 			return (1);
2765 	}
2766 
2767 	return (0);
2768 }
2769 
2770 struct vacm_user *
vacm_new_user(int32_t smodel,char * uname)2771 vacm_new_user(int32_t smodel, char *uname)
2772 {
2773 	int cmp;
2774 	struct vacm_user *user, *temp, *prev;
2775 
2776 	SLIST_FOREACH(user, &vacm_userlist, vvu)
2777 		if (strcmp(uname, user->secname) == 0 &&
2778 		    smodel == user->sec_model)
2779 			return (NULL);
2780 
2781 	if ((user = (struct vacm_user *)malloc(sizeof(*user))) == NULL)
2782 		return (NULL);
2783 
2784 	memset(user, 0, sizeof(*user));
2785 	user->group = &vacm_default_group;
2786 	SLIST_INSERT_HEAD(&vacm_default_group.group_users, user, vvg);
2787 	user->sec_model = smodel;
2788 	strlcpy(user->secname, uname, sizeof(user->secname));
2789 
2790 	if ((prev = SLIST_FIRST(&vacm_userlist)) == NULL ||
2791 	    vacm_compare_user(user, prev) < 0) {
2792 		SLIST_INSERT_HEAD(&vacm_userlist, user, vvu);
2793 		return (user);
2794 	}
2795 
2796 	SLIST_FOREACH(temp, &vacm_userlist, vvu) {
2797 		if ((cmp = vacm_compare_user(user, temp)) <= 0)
2798 			break;
2799 		prev = temp;
2800 	}
2801 
2802 	if (temp == NULL || cmp < 0)
2803 		SLIST_INSERT_AFTER(prev, user, vvu);
2804 	else if (cmp > 0)
2805 		SLIST_INSERT_AFTER(temp, user, vvu);
2806 	else {
2807 		syslog(LOG_ERR, "User %s exists", user->secname);
2808 		free(user);
2809 		return (NULL);
2810 	}
2811 
2812 	return (user);
2813 }
2814 
2815 int
vacm_delete_user(struct vacm_user * user)2816 vacm_delete_user(struct vacm_user *user)
2817 {
2818 	if (user->group != NULL && user->group != &vacm_default_group) {
2819 		SLIST_REMOVE(&user->group->group_users, user, vacm_user, vvg);
2820 		if (SLIST_EMPTY(&user->group->group_users)) {
2821 			SLIST_REMOVE(&vacm_grouplist, user->group,
2822 			    vacm_group, vge);
2823 			free(user->group);
2824 		}
2825 	}
2826 
2827 	SLIST_REMOVE(&vacm_userlist, user, vacm_user, vvu);
2828 	free(user);
2829 
2830 	return (0);
2831 }
2832 
2833 int
vacm_user_set_group(struct vacm_user * user,u_char * octets,u_int len)2834 vacm_user_set_group(struct vacm_user *user, u_char *octets, u_int len)
2835 {
2836 	struct vacm_group *group;
2837 
2838 	if (len >= SNMP_ADM_STR32_SIZ)
2839 		return (-1);
2840 
2841 	SLIST_FOREACH(group, &vacm_grouplist, vge)
2842 		if (strlen(group->groupname) == len &&
2843 		    memcmp(octets, group->groupname, len) == 0)
2844 			break;
2845 
2846 	if (group == NULL) {
2847 		if ((group = (struct vacm_group *)malloc(sizeof(*group))) == NULL)
2848 			return (-1);
2849 		memset(group, 0, sizeof(*group));
2850 		memcpy(group->groupname, octets, len);
2851 		group->groupname[len] = '\0';
2852 		SLIST_INSERT_HEAD(&vacm_grouplist, group, vge);
2853 	}
2854 
2855 	SLIST_REMOVE(&user->group->group_users, user, vacm_user, vvg);
2856 	SLIST_INSERT_HEAD(&group->group_users, user, vvg);
2857 	user->group = group;
2858 
2859 	return (0);
2860 }
2861 
2862 void
vacm_groups_init(void)2863 vacm_groups_init(void)
2864 {
2865 	SLIST_INSERT_HEAD(&vacm_grouplist, &vacm_default_group, vge);
2866 }
2867 
2868 struct vacm_access *
vacm_first_access_rule(void)2869 vacm_first_access_rule(void)
2870 {
2871 	return (TAILQ_FIRST(&vacm_accesslist));
2872 }
2873 
2874 struct vacm_access *
vacm_next_access_rule(struct vacm_access * acl)2875 vacm_next_access_rule(struct vacm_access *acl)
2876 {
2877 	if (acl == NULL)
2878 		return (NULL);
2879 
2880 	return (TAILQ_NEXT(acl, vva));
2881 }
2882 
2883 static int
vacm_compare_access_rule(struct vacm_access * v1,struct vacm_access * v2)2884 vacm_compare_access_rule(struct vacm_access *v1, struct vacm_access *v2)
2885 {
2886 	uint32_t i;
2887 
2888 	if (strlen(v1->group->groupname) < strlen(v2->group->groupname))
2889 		return (-1);
2890 	if (strlen(v1->group->groupname) > strlen(v2->group->groupname))
2891 		return (1);
2892 
2893 	for (i = 0; i < strlen(v1->group->groupname); i++) {
2894 		if (v1->group->groupname[i] < v2->group->groupname[i])
2895 			return (-1);
2896 		if (v1->group->groupname[i] > v2->group->groupname[i])
2897 			return (1);
2898 	}
2899 
2900 	if (strlen(v1->ctx_prefix) < strlen(v2->ctx_prefix))
2901 		return (-1);
2902 	if (strlen(v1->ctx_prefix) > strlen(v2->ctx_prefix))
2903 		return (1);
2904 
2905 	for (i = 0; i < strlen(v1->ctx_prefix); i++) {
2906 		if (v1->ctx_prefix[i] < v2->ctx_prefix[i])
2907 			return (-1);
2908 		if (v1->ctx_prefix[i] > v2->ctx_prefix[i])
2909 			return (1);
2910 	}
2911 
2912 	if (v1->sec_model < v2->sec_model)
2913 		return (-1);
2914 	if (v1->sec_model > v2->sec_model)
2915 		return (1);
2916 
2917 	if (v1->sec_level < v2->sec_level)
2918 		return (-1);
2919 	if (v1->sec_level > v2->sec_level)
2920 		return (1);
2921 
2922 	return (0);
2923 }
2924 
2925 struct vacm_access *
vacm_new_access_rule(char * gname,char * cprefix,int32_t smodel,int32_t slevel)2926 vacm_new_access_rule(char *gname, char *cprefix, int32_t smodel, int32_t slevel)
2927 {
2928 	struct vacm_group *group;
2929 	struct vacm_access *acl, *temp;
2930 
2931 	TAILQ_FOREACH(acl, &vacm_accesslist, vva) {
2932 		if (acl->group == NULL)
2933 			continue;
2934 		if (strcmp(gname, acl->group->groupname) == 0 &&
2935 		    strcmp(cprefix, acl->ctx_prefix) == 0 &&
2936 		    acl->sec_model == smodel && acl->sec_level == slevel)
2937 			return (NULL);
2938 	}
2939 
2940 	/* Make sure the group exists */
2941 	SLIST_FOREACH(group, &vacm_grouplist, vge)
2942 		if (strcmp(gname, group->groupname) == 0)
2943 			break;
2944 
2945 	if (group == NULL)
2946 		return (NULL);
2947 
2948 	if ((acl = (struct vacm_access *)malloc(sizeof(*acl))) == NULL)
2949 		return (NULL);
2950 
2951 	memset(acl, 0, sizeof(*acl));
2952 	acl->group = group;
2953 	strlcpy(acl->ctx_prefix, cprefix, sizeof(acl->ctx_prefix));
2954 	acl->sec_model = smodel;
2955 	acl->sec_level = slevel;
2956 
2957 	if ((temp = TAILQ_FIRST(&vacm_accesslist)) == NULL ||
2958 	    vacm_compare_access_rule(acl, temp) < 0) {
2959 		TAILQ_INSERT_HEAD(&vacm_accesslist, acl, vva);
2960 		return (acl);
2961 	}
2962 
2963 	TAILQ_FOREACH(temp, &vacm_accesslist, vva)
2964 		if (vacm_compare_access_rule(acl, temp) < 0) {
2965 		    	TAILQ_INSERT_BEFORE(temp, acl, vva);
2966 			return (acl);
2967 		}
2968 
2969 	TAILQ_INSERT_TAIL(&vacm_accesslist, acl, vva);
2970 
2971 	return (acl);
2972 }
2973 
2974 int
vacm_delete_access_rule(struct vacm_access * acl)2975 vacm_delete_access_rule(struct vacm_access *acl)
2976 {
2977 	TAILQ_REMOVE(&vacm_accesslist, acl, vva);
2978 	free(acl);
2979 
2980 	return (0);
2981 }
2982 
2983 struct vacm_view *
vacm_first_view(void)2984 vacm_first_view(void)
2985 {
2986 	return (SLIST_FIRST(&vacm_viewlist));
2987 }
2988 
2989 struct vacm_view *
vacm_next_view(struct vacm_view * view)2990 vacm_next_view(struct vacm_view *view)
2991 {
2992 	if (view == NULL)
2993 		return (NULL);
2994 
2995 	return (SLIST_NEXT(view, vvl));
2996 }
2997 
2998 static int
vacm_compare_view(struct vacm_view * v1,struct vacm_view * v2)2999 vacm_compare_view(struct vacm_view *v1, struct vacm_view *v2)
3000 {
3001 	uint32_t i;
3002 
3003 	if (strlen(v1->viewname) < strlen(v2->viewname))
3004 		return (-1);
3005 	if (strlen(v1->viewname) > strlen(v2->viewname))
3006 		return (1);
3007 
3008 	for (i = 0; i < strlen(v1->viewname); i++) {
3009 		if (v1->viewname[i] < v2->viewname[i])
3010 			return (-1);
3011 		if (v1->viewname[i] > v2->viewname[i])
3012 			return (1);
3013 	}
3014 
3015 	return (asn_compare_oid(&v1->subtree, &v2->subtree));
3016 }
3017 
3018 struct vacm_view *
vacm_new_view(char * vname,struct asn_oid * oid)3019 vacm_new_view(char *vname, struct asn_oid *oid)
3020 {
3021 	int cmp;
3022 	struct vacm_view *view, *temp, *prev;
3023 
3024 	SLIST_FOREACH(view, &vacm_viewlist, vvl)
3025 		if (strcmp(vname, view->viewname) == 0)
3026 			return (NULL);
3027 
3028 	if ((view = (struct vacm_view *)malloc(sizeof(*view))) == NULL)
3029 		return (NULL);
3030 
3031 	memset(view, 0, sizeof(*view));
3032 	strlcpy(view->viewname, vname, sizeof(view->viewname));
3033 	asn_append_oid(&view->subtree, oid);
3034 
3035 	if ((prev = SLIST_FIRST(&vacm_viewlist)) == NULL ||
3036 	    vacm_compare_view(view, prev) < 0) {
3037 		SLIST_INSERT_HEAD(&vacm_viewlist, view, vvl);
3038 		return (view);
3039 	}
3040 
3041 	SLIST_FOREACH(temp, &vacm_viewlist, vvl) {
3042 		if ((cmp = vacm_compare_view(view, temp)) <= 0)
3043 			break;
3044 		prev = temp;
3045 	}
3046 
3047 	if (temp == NULL || cmp < 0)
3048 		SLIST_INSERT_AFTER(prev, view, vvl);
3049 	else if (cmp > 0)
3050 		SLIST_INSERT_AFTER(temp, view, vvl);
3051 	else {
3052 		syslog(LOG_ERR, "View %s exists", view->viewname);
3053 		free(view);
3054 		return (NULL);
3055 	}
3056 
3057 	return (view);
3058 }
3059 
3060 int
vacm_delete_view(struct vacm_view * view)3061 vacm_delete_view(struct vacm_view *view)
3062 {
3063 	SLIST_REMOVE(&vacm_viewlist, view, vacm_view, vvl);
3064 	free(view);
3065 
3066 	return (0);
3067 }
3068 
3069 struct vacm_context *
vacm_first_context(void)3070 vacm_first_context(void)
3071 {
3072 	return (SLIST_FIRST(&vacm_contextlist));
3073 }
3074 
3075 struct vacm_context *
vacm_next_context(struct vacm_context * vacmctx)3076 vacm_next_context(struct vacm_context *vacmctx)
3077 {
3078 	if (vacmctx == NULL)
3079 		return (NULL);
3080 
3081 	return (SLIST_NEXT(vacmctx, vcl));
3082 }
3083 
3084 struct vacm_context *
vacm_add_context(char * ctxname,int regid)3085 vacm_add_context(char *ctxname, int regid)
3086 {
3087 	int cmp;
3088 	struct vacm_context *ctx, *temp, *prev;
3089 
3090 	SLIST_FOREACH(ctx, &vacm_contextlist, vcl)
3091 		if (strcmp(ctxname, ctx->ctxname) == 0) {
3092 			syslog(LOG_ERR, "Context %s exists", ctx->ctxname);
3093 			return (NULL);
3094 		}
3095 
3096 	if ((ctx = (struct vacm_context *)malloc(sizeof(*ctx))) == NULL)
3097 		return (NULL);
3098 
3099 	memset(ctx, 0, sizeof(*ctx));
3100 	strlcpy(ctx->ctxname, ctxname, sizeof(ctx->ctxname));
3101 	ctx->regid = regid;
3102 
3103 	if ((prev = SLIST_FIRST(&vacm_contextlist)) == NULL ||
3104 	    strlen(ctx->ctxname) < strlen(prev->ctxname) ||
3105 	    strcmp(ctx->ctxname, prev->ctxname) < 0) {
3106 		SLIST_INSERT_HEAD(&vacm_contextlist, ctx, vcl);
3107 		return (ctx);
3108 	}
3109 
3110 	SLIST_FOREACH(temp, &vacm_contextlist, vcl) {
3111 		if (strlen(ctx->ctxname) < strlen(temp->ctxname) ||
3112 		    strcmp(ctx->ctxname, temp->ctxname) < 0) {
3113 		    	cmp = -1;
3114 			break;
3115 		}
3116 		prev = temp;
3117 	}
3118 
3119 	if (temp == NULL || cmp < 0)
3120 		SLIST_INSERT_AFTER(prev, ctx, vcl);
3121 	else if (cmp > 0)
3122 		SLIST_INSERT_AFTER(temp, ctx, vcl);
3123 	else {
3124 		syslog(LOG_ERR, "Context %s exists", ctx->ctxname);
3125 		free(ctx);
3126 		return (NULL);
3127 	}
3128 
3129 	return (ctx);
3130 }
3131 
3132 void
vacm_flush_contexts(int regid)3133 vacm_flush_contexts(int regid)
3134 {
3135 	struct vacm_context *ctx, *temp;
3136 
3137 	SLIST_FOREACH_SAFE(ctx, &vacm_contextlist, vcl, temp)
3138 		if (ctx->regid == regid) {
3139 			SLIST_REMOVE(&vacm_contextlist, ctx, vacm_context, vcl);
3140 			free(ctx);
3141 		}
3142 }
3143