xref: /freebsd/contrib/bsnmp/snmpd/main.c (revision 183d09305677b7c669eba8ed6fe8d0b879684913)
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 <stdbool.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <stddef.h>
49 #include <string.h>
50 #include <stdarg.h>
51 #include <ctype.h>
52 #include <errno.h>
53 #include <syslog.h>
54 #include <unistd.h>
55 #include <signal.h>
56 #include <dlfcn.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 #include "trans_inet.h"
70 
71 #define	PATH_PID	"/var/run/%s.pid"
72 #define PATH_CONFIG	"/etc/%s.config"
73 #define	PATH_ENGINE	"/var/%s.engine"
74 
75 uint64_t this_tick;	/* start of processing of current packet (absolute) */
76 uint64_t start_tick;	/* start of processing */
77 
78 struct systemg systemg = {
79 	NULL,
80 	{ 8, { 1, 3, 6, 1, 4, 1, 1115, 7352 }},
81 	NULL, NULL, NULL,
82 	64 + 8 + 4,
83 	0
84 };
85 struct debug debug = {
86 	0,		/* dump_pdus */
87 	LOG_DEBUG,	/* log_pri */
88 	0,		/* evdebug */
89 };
90 
91 struct snmpd snmpd = {
92 	2048,		/* txbuf */
93 	2048,		/* rxbuf */
94 	0,		/* comm_dis */
95 	0,		/* auth_traps */
96 	{0, 0, 0, 0},	/* trap1addr */
97 	VERS_ENABLE_ALL,/* version_enable */
98 };
99 struct snmpd_stats snmpd_stats;
100 
101 struct snmpd_usmstat snmpd_usmstats;
102 
103 /* snmpEngine */
104 struct snmp_engine snmpd_engine;
105 
106 /* snmpSerialNo */
107 int32_t snmp_serial_no;
108 
109 struct snmpd_target_stats snmpd_target_stats;
110 
111 /* search path for config files */
112 const char *syspath = PATH_SYSCONFIG;
113 
114 /* list of all loaded modules */
115 struct lmodules lmodules = TAILQ_HEAD_INITIALIZER(lmodules);
116 
117 /* list of loaded modules during start-up in the order they were loaded */
118 static struct lmodules modules_start = TAILQ_HEAD_INITIALIZER(modules_start);
119 
120 /* list of all known communities */
121 struct community_list community_list = TAILQ_HEAD_INITIALIZER(community_list);
122 
123 /* list of all known USM users */
124 static struct usm_userlist usm_userlist = SLIST_HEAD_INITIALIZER(usm_userlist);
125 
126 /* A list of all VACM users configured, including v1, v2c and v3 */
127 static struct vacm_userlist vacm_userlist =
128     SLIST_HEAD_INITIALIZER(vacm_userlist);
129 
130 /* A list of all VACM groups */
131 static struct vacm_grouplist vacm_grouplist =
132     SLIST_HEAD_INITIALIZER(vacm_grouplist);
133 
134 static struct vacm_group vacm_default_group = {
135 	.groupname = "",
136 };
137 
138 /* The list of configured access entries */
139 static struct vacm_accesslist vacm_accesslist =
140     TAILQ_HEAD_INITIALIZER(vacm_accesslist);
141 
142 /* The list of configured views */
143 static struct vacm_viewlist vacm_viewlist =
144     SLIST_HEAD_INITIALIZER(vacm_viewlist);
145 
146 /* The list of configured contexts */
147 static struct vacm_contextlist vacm_contextlist =
148     SLIST_HEAD_INITIALIZER(vacm_contextlist);
149 
150 /* list of all installed object resources */
151 struct objres_list objres_list = TAILQ_HEAD_INITIALIZER(objres_list);
152 
153 /* community value generator */
154 static u_int next_community_index = 1;
155 
156 /* list of all known ranges */
157 struct idrange_list idrange_list = TAILQ_HEAD_INITIALIZER(idrange_list);
158 
159 /* identifier generator */
160 u_int next_idrange = 1;
161 
162 /* list of all current timers */
163 struct timer_list timer_list = LIST_HEAD_INITIALIZER(timer_list);
164 
165 /* list of file descriptors */
166 struct fdesc_list fdesc_list = LIST_HEAD_INITIALIZER(fdesc_list);
167 
168 /* program arguments */
169 static char **progargs;
170 static int nprogargs;
171 
172 /* current community */
173 u_int	community;
174 static struct community *comm;
175 
176 /* current USM user */
177 struct usm_user *usm_user;
178 
179 /* file names */
180 static char config_file[MAXPATHLEN + 1];
181 static char pid_file[MAXPATHLEN + 1];
182 char engine_file[MAXPATHLEN + 1];
183 
184 #ifndef USE_LIBBEGEMOT
185 /* event context */
186 static evContext evctx;
187 #endif
188 
189 /* signal mask */
190 static sigset_t blocked_sigs;
191 
192 /* signal handling */
193 static int work;
194 #define	WORK_DOINFO	0x0001
195 #define	WORK_RECONFIG	0x0002
196 
197 /* oids */
198 static const struct asn_oid
199 	oid_snmpMIB = OIDX_snmpMIB,
200 	oid_begemotSnmpd = OIDX_begemotSnmpd,
201 	oid_coldStart = OIDX_coldStart,
202 	oid_authenticationFailure = OIDX_authenticationFailure;
203 
204 const struct asn_oid oid_zeroDotZero = { 2, { 0, 0 }};
205 
206 const struct asn_oid oid_usmUnknownEngineIDs =
207 	{ 11, { 1, 3, 6, 1, 6, 3, 15, 1, 1, 4, 0}};
208 
209 const struct asn_oid oid_usmNotInTimeWindows =
210 	{ 11, { 1, 3, 6, 1, 6, 3, 15, 1, 1, 2, 0}};
211 
212 /* request id generator for traps */
213 u_int trap_reqid;
214 
215 /* help text */
216 static const char usgtxt[] = "\
217 Begemot simple SNMP daemon. Copyright (c) 2001-2002 Fraunhofer Institute for\n\
218 Open Communication Systems (FhG Fokus). All rights reserved.\n\
219 Copyright (c) 2010 The FreeBSD Foundation. All rights reserved.\n\
220 usage: snmpd [-dh] [-c file] [-D options] [-e file] [-I path]\n\
221              [-l prefix] [-m variable=value] [-p file]\n\
222 options:\n\
223   -d		don't daemonize\n\
224   -h		print this info\n\
225   -c file	specify configuration file\n\
226   -D options	debugging options\n\
227   -e file	specify engine id file\n\
228   -I path	system include path\n\
229   -l prefix	default basename for pid and config file\n\
230   -m var=val	define variable\n\
231   -p file	specify pid file\n\
232 ";
233 
234 /* hosts_access(3) request */
235 #ifdef USE_TCPWRAPPERS
236 static struct request_info req;
237 #endif
238 
239 /* transports */
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 		slen = tport->transport->vtab->send(tport, sndbuf, sndlen, pi);
1190 		if (slen == -1)
1191 			syslog(LOG_ERR, "send*: %m");
1192 		else if ((size_t)slen != sndlen)
1193 			syslog(LOG_ERR, "send*: short write %zu/%zu", sndlen,
1194 			    (size_t)slen);
1195 	}
1196 
1197 	snmp_pdu_free(&pdu);
1198 	free(sndbuf);
1199 	snmp_input_consume(pi);
1200 
1201 	return (0);
1202 }
1203 
1204 /*
1205  * Send a PDU to a given port. If this is a multi-socket port, use the
1206  * first socket.
1207  */
1208 void
snmp_send_port(void * targ,const struct asn_oid * port,struct snmp_pdu * pdu,const struct sockaddr * addr,socklen_t addrlen)1209 snmp_send_port(void *targ, const struct asn_oid *port, struct snmp_pdu *pdu,
1210     const struct sockaddr *addr, socklen_t addrlen)
1211 {
1212 	struct port_input pi = {
1213 		.fd = -1,
1214 		.peer = __DECONST(struct sockaddr *, addr),
1215 		.peerlen = 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 	len = trans->vtab->send(tp, sndbuf, sndlen, &pi);
1235 
1236 	if (len == -1)
1237 		syslog(LOG_ERR, "sendto: %m");
1238 	else if ((size_t)len != sndlen)
1239 		syslog(LOG_ERR, "sendto: short write %zu/%zu",
1240 		    sndlen, (size_t)len);
1241 
1242 	free(sndbuf);
1243 }
1244 
1245 
1246 /*
1247  * Close an input source
1248  *
1249  * \param pi	input instance
1250  */
1251 void
snmpd_input_close(struct port_input * pi)1252 snmpd_input_close(struct port_input *pi)
1253 {
1254 	if (pi->id != NULL) {
1255 		fd_deselect(pi->id);
1256 		pi->id = NULL;
1257 	}
1258 	if (pi->fd >= 0) {
1259 		(void)close(pi->fd);
1260 		pi->fd = -1;
1261 	}
1262 	if (pi->buf != NULL) {
1263 		free(pi->buf);
1264 		pi->buf = NULL;
1265 	}
1266 }
1267 
1268 /*
1269  * Initialize an input source.
1270  *
1271  * \param pi	input instance
1272  */
1273 void
snmpd_input_init(struct port_input * pi)1274 snmpd_input_init(struct port_input *pi)
1275 {
1276 	pi->id = NULL;
1277 	pi->fd = -1;
1278 	pi->buf = NULL;
1279 }
1280 
1281 /*
1282  * Dump internal state.
1283  */
1284 #ifdef USE_LIBBEGEMOT
1285 static void
info_func(void)1286 info_func(void)
1287 #else
1288 static void
1289 info_func(evContext ctx __unused, void *uap __unused, const void *tag __unused)
1290 #endif
1291 {
1292 	struct lmodule *m;
1293 	u_int i;
1294 	char buf[10000];
1295 
1296 	syslog(LOG_DEBUG, "Dump of SNMPd %lu\n", (u_long)getpid());
1297 	for (i = 0; i < tree_size; i++) {
1298 		switch (tree[i].type) {
1299 
1300 		  case SNMP_NODE_LEAF:
1301 			sprintf(buf, "LEAF: %s %s", tree[i].name,
1302 			    asn_oid2str(&tree[i].oid));
1303 			break;
1304 
1305 		  case SNMP_NODE_COLUMN:
1306 			sprintf(buf, "COL: %s %s", tree[i].name,
1307 			    asn_oid2str(&tree[i].oid));
1308 			break;
1309 		}
1310 		syslog(LOG_DEBUG, "%s", buf);
1311 	}
1312 
1313 	TAILQ_FOREACH(m, &lmodules, link)
1314 		if (m->config->dump)
1315 			(*m->config->dump)();
1316 }
1317 
1318 /*
1319  * Re-read configuration
1320  */
1321 #ifdef USE_LIBBEGEMOT
1322 static void
config_func(void)1323 config_func(void)
1324 #else
1325 static void
1326 config_func(evContext ctx __unused, void *uap __unused,
1327     const void *tag __unused)
1328 #endif
1329 {
1330 	struct lmodule *m;
1331 
1332 	if (read_config(config_file, NULL)) {
1333 		syslog(LOG_ERR, "error reading config file '%s'", config_file);
1334 		return;
1335 	}
1336 	TAILQ_FOREACH(m, &lmodules, link)
1337 		if (m->config->config)
1338 			(*m->config->config)();
1339 }
1340 
1341 /*
1342  * On USR1 dump actual configuration.
1343  */
1344 static void
onusr1(int s __unused)1345 onusr1(int s __unused)
1346 {
1347 
1348 	work |= WORK_DOINFO;
1349 }
1350 static void
onhup(int s __unused)1351 onhup(int s __unused)
1352 {
1353 
1354 	work |= WORK_RECONFIG;
1355 }
1356 
1357 static void
onterm(int s __unused)1358 onterm(int s __unused)
1359 {
1360 
1361 	/* allow clean-up */
1362 	exit(0);
1363 }
1364 
1365 static void
init_sigs(void)1366 init_sigs(void)
1367 {
1368 	struct sigaction sa;
1369 
1370 	sa.sa_handler = onusr1;
1371 	sa.sa_flags = SA_RESTART;
1372 	sigemptyset(&sa.sa_mask);
1373 	if (sigaction(SIGUSR1, &sa, NULL)) {
1374 		syslog(LOG_ERR, "sigaction: %m");
1375 		exit(1);
1376 	}
1377 
1378 	sa.sa_handler = onhup;
1379 	if (sigaction(SIGHUP, &sa, NULL)) {
1380 		syslog(LOG_ERR, "sigaction: %m");
1381 		exit(1);
1382 	}
1383 
1384 	sa.sa_handler = onterm;
1385 	sa.sa_flags = 0;
1386 	sigemptyset(&sa.sa_mask);
1387 	if (sigaction(SIGTERM, &sa, NULL)) {
1388 		syslog(LOG_ERR, "sigaction: %m");
1389 		exit(1);
1390 	}
1391 	if (sigaction(SIGINT, &sa, NULL)) {
1392 		syslog(LOG_ERR, "sigaction: %m");
1393 		exit(1);
1394 	}
1395 }
1396 
1397 static void
block_sigs(void)1398 block_sigs(void)
1399 {
1400 	sigset_t set;
1401 
1402 	sigfillset(&set);
1403 	if (sigprocmask(SIG_BLOCK, &set, &blocked_sigs) == -1) {
1404 		syslog(LOG_ERR, "SIG_BLOCK: %m");
1405 		exit(1);
1406 	}
1407 }
1408 static void
unblock_sigs(void)1409 unblock_sigs(void)
1410 {
1411 	if (sigprocmask(SIG_SETMASK, &blocked_sigs, NULL) == -1) {
1412 		syslog(LOG_ERR, "SIG_SETMASK: %m");
1413 		exit(1);
1414 	}
1415 }
1416 
1417 /*
1418  * Shut down
1419  */
1420 static void
term(void)1421 term(void)
1422 {
1423 	(void)unlink(pid_file);
1424 }
1425 
1426 static void
trans_stop(void)1427 trans_stop(void)
1428 {
1429 	struct transport *t;
1430 
1431 	TAILQ_FOREACH(t, &transport_list, link)
1432 		(void)t->vtab->stop(1);
1433 }
1434 
1435 /*
1436  * Define a macro from the command line
1437  */
1438 static void
do_macro(char * arg)1439 do_macro(char *arg)
1440 {
1441 	char *eq;
1442 	int err;
1443 
1444 	if ((eq = strchr(arg, '=')) == NULL)
1445 		err = define_macro(arg, "");
1446 	else {
1447 		*eq++ = '\0';
1448 		err = define_macro(arg, eq);
1449 	}
1450 	if (err == -1) {
1451 		syslog(LOG_ERR, "cannot save macro: %m");
1452 		exit(1);
1453 	}
1454 }
1455 
1456 /*
1457  * Re-implement getsubopt from scratch, because the second argument is broken
1458  * and will not compile with WARNS=5.
1459  */
1460 static int
getsubopt1(char ** arg,const char * const * options,char ** valp,char ** optp)1461 getsubopt1(char **arg, const char *const *options, char **valp, char **optp)
1462 {
1463 	static const char *const delim = ",\t ";
1464 	u_int i;
1465 	char *ptr;
1466 
1467 	*optp = NULL;
1468 
1469 	/* skip leading junk */
1470 	for (ptr = *arg; *ptr != '\0'; ptr++)
1471 		if (strchr(delim, *ptr) == NULL)
1472 			break;
1473 	if (*ptr == '\0') {
1474 		*arg = ptr;
1475 		return (-1);
1476 	}
1477 	*optp = ptr;
1478 
1479 	/* find the end of the option */
1480 	while (*++ptr != '\0')
1481 		if (strchr(delim, *ptr) != NULL || *ptr == '=')
1482 			break;
1483 
1484 	if (*ptr != '\0') {
1485 		if (*ptr == '=') {
1486 			*ptr++ = '\0';
1487 			*valp = ptr;
1488 			while (*ptr != '\0' && strchr(delim, *ptr) == NULL)
1489 				ptr++;
1490 			if (*ptr != '\0')
1491 				*ptr++ = '\0';
1492 		} else
1493 			*ptr++ = '\0';
1494 	}
1495 
1496 	*arg = ptr;
1497 
1498 	for (i = 0; *options != NULL; options++, i++)
1499 		if (strcmp(*optp, *options) == 0)
1500 			return (i);
1501 	return (-1);
1502 }
1503 
1504 int
main(int argc,char * argv[])1505 main(int argc, char *argv[])
1506 {
1507 	int opt;
1508 	FILE *fp;
1509 	bool background = true;
1510 	struct tport *p;
1511 	const char *prefix = "snmpd";
1512 	struct lmodule *m;
1513 	char *value = NULL, *option; /* XXX */
1514 	struct transport *t;
1515 
1516 #define DBG_DUMP	0
1517 #define DBG_EVENTS	1
1518 #define DBG_TRACE	2
1519 	static const char *const debug_opts[] = {
1520 		"dump",
1521 		"events",
1522 		"trace",
1523 		NULL
1524 	};
1525 
1526 	while ((opt = getopt(argc, argv, "c:dD:e:hI:l:m:p:")) != EOF)
1527 		switch (opt) {
1528 
1529 		  case 'c':
1530 			strlcpy(config_file, optarg, sizeof(config_file));
1531 			break;
1532 
1533 		  case 'd':
1534 			background = false;
1535 			break;
1536 
1537 		  case 'D':
1538 			while (*optarg) {
1539 				switch (getsubopt1(&optarg, debug_opts,
1540 				    &value, &option)) {
1541 
1542 				  case DBG_DUMP:
1543 					debug.dump_pdus = 1;
1544 					break;
1545 
1546 				  case DBG_EVENTS:
1547 					debug.evdebug++;
1548 					break;
1549 
1550 				  case DBG_TRACE:
1551 					if (value == NULL)
1552 						syslog(LOG_ERR,
1553 						    "no value for 'trace'");
1554 					else
1555 						snmp_trace = strtoul(value,
1556 						    NULL, 0);
1557 					break;
1558 
1559 				  case -1:
1560 					if (suboptarg)
1561 						syslog(LOG_ERR,
1562 						    "unknown debug flag '%s'",
1563 						    option);
1564 					else
1565 						syslog(LOG_ERR,
1566 						    "missing debug flag");
1567 					break;
1568 				}
1569 			}
1570 			break;
1571 
1572 		  case 'e':
1573 			strlcpy(engine_file, optarg, sizeof(engine_file));
1574 			break;
1575 		  case 'h':
1576 			fprintf(stderr, "%s", usgtxt);
1577 			exit(0);
1578 
1579 		  case 'I':
1580 			syspath = optarg;
1581 			break;
1582 
1583 		  case 'l':
1584 			prefix = optarg;
1585 			break;
1586 
1587 		  case 'm':
1588 			do_macro(optarg);
1589 			break;
1590 
1591 		  case 'p':
1592 			strlcpy(pid_file, optarg, sizeof(pid_file));
1593 			break;
1594 		}
1595 
1596 	if (background) {
1597 		snmp_printf = snmp_printf_func;
1598 		snmp_error = snmp_error_func;
1599 		snmp_debug = snmp_debug_func;
1600 		asn_error = asn_error_func;
1601 	}
1602 
1603 	openlog(prefix, LOG_PID | (background ? 0 : LOG_PERROR), LOG_USER);
1604 	setlogmask(LOG_UPTO(debug.logpri - 1));
1605 
1606 	if (background && daemon(0, 0) < 0) {
1607 		syslog(LOG_ERR, "daemon: %m");
1608 		exit(1);
1609 	}
1610 
1611 	argc -= optind;
1612 	argv += optind;
1613 
1614 	progargs = argv;
1615 	nprogargs = argc;
1616 
1617 	snmp_serial_no = arc4random();
1618 
1619 #ifdef USE_TCPWRAPPERS
1620 	/*
1621 	 * Initialize hosts_access(3) handler.
1622 	 */
1623 	request_init(&req, RQ_DAEMON, "snmpd", 0);
1624 	sock_methods(&req);
1625 #endif
1626 
1627 	/*
1628 	 * Initialize the tree.
1629 	 */
1630 	if ((tree = malloc(sizeof(struct snmp_node) * CTREE_SIZE)) == NULL) {
1631 		syslog(LOG_ERR, "%m");
1632 		exit(1);
1633 	}
1634 	memcpy(tree, ctree, sizeof(struct snmp_node) * CTREE_SIZE);
1635 	tree_size = CTREE_SIZE;
1636 
1637 	/*
1638 	 * Get standard communities
1639 	 */
1640 	comm_define(COMM_READ, "SNMP read", NULL, NULL);
1641 	comm_define(COMM_WRITE, "SNMP write", NULL, NULL);
1642 	community = COMM_INITIALIZE;
1643 
1644 	trap_reqid = reqid_allocate(512, NULL);
1645 
1646 	if (config_file[0] == '\0')
1647 		snprintf(config_file, sizeof(config_file), PATH_CONFIG, prefix);
1648 
1649 	init_actvals();
1650 	init_snmpd_engine();
1651 
1652 	this_tick = get_ticks();
1653 	start_tick = this_tick;
1654 
1655 	/* start transports */
1656 	if (atexit(trans_stop) == -1) {
1657 		syslog(LOG_ERR, "atexit failed: %m");
1658 		exit(1);
1659 	}
1660 	if (lsock_trans.start() != SNMP_ERR_NOERROR)
1661 		syslog(LOG_WARNING, "cannot start LSOCK transport");
1662 	if (inet_trans.start() != SNMP_ERR_NOERROR)
1663 		syslog(LOG_WARNING, "cannot start INET transport");
1664 
1665 #ifdef USE_LIBBEGEMOT
1666 	if (debug.evdebug > 0)
1667 		rpoll_trace = 1;
1668 #else
1669 	if (evCreate(&evctx)) {
1670 		syslog(LOG_ERR, "evCreate: %m");
1671 		exit(1);
1672 	}
1673 	if (debug.evdebug > 0)
1674 		evSetDebug(evctx, 10, stderr);
1675 #endif
1676 
1677 	if (engine_file[0] == '\0')
1678 		snprintf(engine_file, sizeof(engine_file), PATH_ENGINE, prefix);
1679 
1680 	if (read_config(config_file, NULL)) {
1681 		syslog(LOG_ERR, "error in config file");
1682 		exit(1);
1683 	}
1684 
1685 	TAILQ_FOREACH(t, &transport_list, link)
1686 		TAILQ_FOREACH(p, &t->table, link)
1687 			t->vtab->init_port(p);
1688 
1689 	init_sigs();
1690 
1691 	if (pid_file[0] == '\0')
1692 		snprintf(pid_file, sizeof(pid_file), PATH_PID, prefix);
1693 
1694 	if ((fp = fopen(pid_file, "w")) != NULL) {
1695 		fprintf(fp, "%u", getpid());
1696 		fclose(fp);
1697 		if (atexit(term) == -1) {
1698 			syslog(LOG_ERR, "atexit failed: %m");
1699 			(void)remove(pid_file);
1700 			exit(0);
1701 		}
1702 	}
1703 
1704 	if (or_register(&oid_snmpMIB, "The MIB module for SNMPv2 entities.",
1705 	    NULL) == 0) {
1706 		syslog(LOG_ERR, "cannot register SNMPv2 MIB");
1707 		exit(1);
1708 	}
1709 	if (or_register(&oid_begemotSnmpd, "The MIB module for the Begemot SNMPd.",
1710 	    NULL) == 0) {
1711 		syslog(LOG_ERR, "cannot register begemotSnmpd MIB");
1712 		exit(1);
1713 	}
1714 
1715 	while ((m = TAILQ_FIRST(&modules_start)) != NULL) {
1716 		m->flags &= ~LM_ONSTARTLIST;
1717 		TAILQ_REMOVE(&modules_start, m, start);
1718 		lm_start(m);
1719 	}
1720 
1721 	snmp_send_trap(&oid_coldStart, (struct snmp_value *)NULL);
1722 
1723 	for (;;) {
1724 #ifndef USE_LIBBEGEMOT
1725 		evEvent event;
1726 #endif
1727 		struct lmodule *mod;
1728 
1729 		TAILQ_FOREACH(mod, &lmodules, link)
1730 			if (mod->config->idle != NULL)
1731 				(*mod->config->idle)();
1732 
1733 #ifndef USE_LIBBEGEMOT
1734 		if (evGetNext(evctx, &event, EV_WAIT) == 0) {
1735 			if (evDispatch(evctx, event))
1736 				syslog(LOG_ERR, "evDispatch: %m");
1737 		} else if (errno != EINTR) {
1738 			syslog(LOG_ERR, "evGetNext: %m");
1739 			exit(1);
1740 		}
1741 #else
1742 		poll_dispatch(1);
1743 #endif
1744 
1745 		if (work != 0) {
1746 			block_sigs();
1747 			if (work & WORK_DOINFO) {
1748 #ifdef USE_LIBBEGEMOT
1749 				info_func();
1750 #else
1751 				if (evWaitFor(evctx, &work, info_func,
1752 				    NULL, NULL) == -1) {
1753 					syslog(LOG_ERR, "evWaitFor: %m");
1754 					exit(1);
1755 				}
1756 #endif
1757 			}
1758 			if (work & WORK_RECONFIG) {
1759 #ifdef USE_LIBBEGEMOT
1760 				config_func();
1761 #else
1762 				if (evWaitFor(evctx, &work, config_func,
1763 				    NULL, NULL) == -1) {
1764 					syslog(LOG_ERR, "evWaitFor: %m");
1765 					exit(1);
1766 				}
1767 #endif
1768 			}
1769 			work = 0;
1770 			unblock_sigs();
1771 #ifndef USE_LIBBEGEMOT
1772 			if (evDo(evctx, &work) == -1) {
1773 				syslog(LOG_ERR, "evDo: %m");
1774 				exit(1);
1775 			}
1776 #endif
1777 		}
1778 	}
1779 
1780 	return (0);
1781 }
1782 
1783 uint64_t
get_ticks(void)1784 get_ticks(void)
1785 {
1786 	struct timeval tv;
1787 	uint64_t ret;
1788 
1789 	if (gettimeofday(&tv, NULL))
1790 		abort();
1791 	ret = tv.tv_sec * 100ULL + tv.tv_usec / 10000ULL;
1792 	return (ret);
1793 }
1794 
1795 /*
1796  * Timer support
1797  */
1798 
1799 /*
1800  * Trampoline for the non-repeatable timers.
1801  */
1802 #ifdef USE_LIBBEGEMOT
1803 static void
tfunc(int tid __unused,void * uap)1804 tfunc(int tid __unused, void *uap)
1805 #else
1806 static void
1807 tfunc(evContext ctx __unused, void *uap, struct timespec due __unused,
1808 	struct timespec inter __unused)
1809 #endif
1810 {
1811 	struct timer *tp = uap;
1812 
1813 	LIST_REMOVE(tp, link);
1814 	tp->func(tp->udata);
1815 	free(tp);
1816 }
1817 
1818 /*
1819  * Trampoline for the repeatable timers.
1820  */
1821 #ifdef USE_LIBBEGEMOT
1822 static void
trfunc(int tid __unused,void * uap)1823 trfunc(int tid __unused, void *uap)
1824 #else
1825 static void
1826 trfunc(evContext ctx __unused, void *uap, struct timespec due __unused,
1827 	struct timespec inter __unused)
1828 #endif
1829 {
1830 	struct timer *tp = uap;
1831 
1832 	tp->func(tp->udata);
1833 }
1834 
1835 /*
1836  * Start a one-shot timer
1837  */
1838 void *
timer_start(u_int ticks,void (* func)(void *),void * udata,struct lmodule * mod)1839 timer_start(u_int ticks, void (*func)(void *), void *udata, struct lmodule *mod)
1840 {
1841 	struct timer *tp;
1842 #ifndef USE_LIBBEGEMOT
1843 	struct timespec due;
1844 #endif
1845 
1846 	if ((tp = malloc(sizeof(struct timer))) == NULL) {
1847 		syslog(LOG_CRIT, "out of memory for timer");
1848 		exit(1);
1849 	}
1850 
1851 #ifndef USE_LIBBEGEMOT
1852 	due = evAddTime(evNowTime(),
1853 	    evConsTime(ticks / 100, (ticks % 100) * 10000));
1854 #endif
1855 
1856 	tp->udata = udata;
1857 	tp->owner = mod;
1858 	tp->func = func;
1859 
1860 	LIST_INSERT_HEAD(&timer_list, tp, link);
1861 
1862 #ifdef USE_LIBBEGEMOT
1863 	if ((tp->id = poll_start_timer(ticks * 10, 0, tfunc, tp)) < 0) {
1864 		syslog(LOG_ERR, "cannot set timer: %m");
1865 		exit(1);
1866 	}
1867 #else
1868 	if (evSetTimer(evctx, tfunc, tp, due, evConsTime(0, 0), &tp->id)
1869 	    == -1) {
1870 		syslog(LOG_ERR, "cannot set timer: %m");
1871 		exit(1);
1872 	}
1873 #endif
1874 	return (tp);
1875 }
1876 
1877 /*
1878  * Start a repeatable timer. When used with USE_LIBBEGEMOT the first argument
1879  * is currently ignored and the initial number of ticks is set to the
1880  * repeat number of ticks.
1881  */
1882 void *
timer_start_repeat(u_int ticks __unused,u_int repeat_ticks,void (* func)(void *),void * udata,struct lmodule * mod)1883 timer_start_repeat(u_int ticks __unused, u_int repeat_ticks,
1884     void (*func)(void *), void *udata, struct lmodule *mod)
1885 {
1886 	struct timer *tp;
1887 #ifndef USE_LIBBEGEMOT
1888 	struct timespec due;
1889 	struct timespec inter;
1890 #endif
1891 
1892 	if ((tp = malloc(sizeof(struct timer))) == NULL) {
1893 		syslog(LOG_CRIT, "out of memory for timer");
1894 		exit(1);
1895 	}
1896 
1897 #ifndef USE_LIBBEGEMOT
1898 	due = evAddTime(evNowTime(),
1899 	    evConsTime(ticks / 100, (ticks % 100) * 10000));
1900 	inter = evConsTime(repeat_ticks / 100, (repeat_ticks % 100) * 10000);
1901 #endif
1902 
1903 	tp->udata = udata;
1904 	tp->owner = mod;
1905 	tp->func = func;
1906 
1907 	LIST_INSERT_HEAD(&timer_list, tp, link);
1908 
1909 #ifdef USE_LIBBEGEMOT
1910 	if ((tp->id = poll_start_timer(repeat_ticks * 10, 1, trfunc, tp)) < 0) {
1911 		syslog(LOG_ERR, "cannot set timer: %m");
1912 		exit(1);
1913 	}
1914 #else
1915 	if (evSetTimer(evctx, trfunc, tp, due, inter, &tp->id) == -1) {
1916 		syslog(LOG_ERR, "cannot set timer: %m");
1917 		exit(1);
1918 	}
1919 #endif
1920 	return (tp);
1921 }
1922 
1923 /*
1924  * Stop a timer.
1925  */
1926 void
timer_stop(void * p)1927 timer_stop(void *p)
1928 {
1929 	struct timer *tp = p;
1930 
1931 	LIST_REMOVE(tp, link);
1932 #ifdef USE_LIBBEGEMOT
1933 	poll_stop_timer(tp->id);
1934 #else
1935 	if (evClearTimer(evctx, tp->id) == -1) {
1936 		syslog(LOG_ERR, "cannot stop timer: %m");
1937 		exit(1);
1938 	}
1939 #endif
1940 	free(p);
1941 }
1942 
1943 static void
timer_flush(struct lmodule * mod)1944 timer_flush(struct lmodule *mod)
1945 {
1946 	struct timer *t, *t1;
1947 
1948 	t = LIST_FIRST(&timer_list);
1949 	while (t != NULL) {
1950 		t1 = LIST_NEXT(t, link);
1951 		if (t->owner == mod)
1952 			timer_stop(t);
1953 		t = t1;
1954 	}
1955 }
1956 
1957 static void
snmp_printf_func(const char * fmt,...)1958 snmp_printf_func(const char *fmt, ...)
1959 {
1960 	va_list ap;
1961 	static char *pend = NULL;
1962 	char *ret, *new;
1963 
1964 	va_start(ap, fmt);
1965 	vasprintf(&ret, fmt, ap);
1966 	va_end(ap);
1967 
1968 	if (ret == NULL)
1969 		return;
1970 	if (pend != NULL) {
1971 		if ((new = realloc(pend, strlen(pend) + strlen(ret) + 1))
1972 		    == NULL) {
1973 			free(ret);
1974 			return;
1975 		}
1976 		pend = new;
1977 		strcat(pend, ret);
1978 		free(ret);
1979 	} else
1980 		pend = ret;
1981 
1982 	while ((ret = strchr(pend, '\n')) != NULL) {
1983 		*ret = '\0';
1984 		syslog(LOG_DEBUG, "%s", pend);
1985 		if (strlen(ret + 1) == 0) {
1986 			free(pend);
1987 			pend = NULL;
1988 			break;
1989 		}
1990 		strcpy(pend, ret + 1);
1991 	}
1992 }
1993 
1994 static void
snmp_error_func(const char * err,...)1995 snmp_error_func(const char *err, ...)
1996 {
1997 	char errbuf[1000];
1998 	va_list ap;
1999 
2000 	if (!(snmp_trace & LOG_SNMP_ERRORS))
2001 		return;
2002 
2003 	va_start(ap, err);
2004 	snprintf(errbuf, sizeof(errbuf), "SNMP: ");
2005 	vsnprintf(errbuf + strlen(errbuf),
2006 	    sizeof(errbuf) - strlen(errbuf), err, ap);
2007 	va_end(ap);
2008 
2009 	syslog(LOG_ERR, "%s", errbuf);
2010 }
2011 
2012 static void
snmp_debug_func(const char * err,...)2013 snmp_debug_func(const char *err, ...)
2014 {
2015 	char errbuf[1000];
2016 	va_list ap;
2017 
2018 	va_start(ap, err);
2019 	snprintf(errbuf, sizeof(errbuf), "SNMP: ");
2020 	vsnprintf(errbuf+strlen(errbuf), sizeof(errbuf)-strlen(errbuf),
2021 	    err, ap);
2022 	va_end(ap);
2023 
2024 	syslog(LOG_DEBUG, "%s", errbuf);
2025 }
2026 
2027 static void
asn_error_func(const struct asn_buf * b,const char * err,...)2028 asn_error_func(const struct asn_buf *b, const char *err, ...)
2029 {
2030 	char errbuf[1000];
2031 	va_list ap;
2032 	u_int i;
2033 
2034 	if (!(snmp_trace & LOG_ASN1_ERRORS))
2035 		return;
2036 
2037 	va_start(ap, err);
2038 	snprintf(errbuf, sizeof(errbuf), "ASN.1: ");
2039 	vsnprintf(errbuf + strlen(errbuf),
2040 	    sizeof(errbuf) - strlen(errbuf), err, ap);
2041 	va_end(ap);
2042 
2043 	if (b != NULL) {
2044 		snprintf(errbuf + strlen(errbuf),
2045 		    sizeof(errbuf) - strlen(errbuf), " at");
2046 		for (i = 0; b->asn_len > i; i++)
2047 			snprintf(errbuf + strlen(errbuf),
2048 			    sizeof(errbuf) - strlen(errbuf),
2049 			    " %02x", b->asn_cptr[i]);
2050 	}
2051 
2052 	syslog(LOG_ERR, "%s", errbuf);
2053 }
2054 
2055 /*
2056  * Create a new community
2057  */
2058 struct community*
comm_define_ordered(u_int priv,const char * descr,struct asn_oid * idx,struct lmodule * owner,const char * str)2059 comm_define_ordered(u_int priv, const char *descr, struct asn_oid *idx,
2060     struct lmodule *owner, const char *str)
2061 {
2062 	struct community *c, *p;
2063 	u_int ncomm;
2064 
2065 	ncomm = idx->subs[idx->len - 1];
2066 
2067 	/* check that community doesn't already exist */
2068 	TAILQ_FOREACH(c, &community_list, link)
2069 		if (c->value == ncomm)
2070 			return (c);
2071 
2072 	if ((c = malloc(sizeof(struct community))) == NULL) {
2073 		syslog(LOG_ERR, "%s: %m", __func__);
2074 		return (NULL);
2075 	}
2076 	c->owner = owner;
2077 	c->value = ncomm;
2078 	c->descr = descr;
2079 	c->string = NULL;
2080 	c->private = priv;
2081 
2082 	if (str != NULL) {
2083 		if((c->string = malloc(strlen(str)+1)) == NULL) {
2084 			free(c);
2085 			return (NULL);
2086 		}
2087 		strcpy(c->string, str);
2088 	}
2089 	/*
2090 	 * Insert ordered
2091 	 */
2092 	c->index = *idx;
2093 	TAILQ_FOREACH(p, &community_list, link) {
2094 		if (asn_compare_oid(&p->index, &c->index) > 0) {
2095 			TAILQ_INSERT_BEFORE(p, c, link);
2096 			break;
2097 		}
2098 	}
2099 	if (p == NULL)
2100 		TAILQ_INSERT_TAIL(&community_list, c, link);
2101 	return (c);
2102 }
2103 
2104 u_int
comm_define(u_int priv,const char * descr,struct lmodule * owner,const char * str)2105 comm_define(u_int priv, const char *descr, struct lmodule *owner,
2106     const char *str)
2107 {
2108 	struct asn_oid idx, *p;
2109 	struct community *c;
2110 	u_int ncomm;
2111 
2112 	/* generate an identifier */
2113 	do {
2114 		if ((ncomm = next_community_index++) == UINT_MAX)
2115 			next_community_index = 1;
2116 		TAILQ_FOREACH(c, &community_list, link)
2117 			if (c->value == ncomm)
2118 				break;
2119 	} while (c != NULL);
2120 
2121 	/* make index */
2122 	if (owner != NULL)
2123 		p = &owner->index;
2124 	else {
2125 		p = &idx;
2126 		p->len = 1;
2127 		p->subs[0] = 0;
2128 	}
2129 	p->subs[p->len++] = ncomm;
2130 	c = comm_define_ordered(priv, descr, p, owner, str);
2131 	if (c == NULL)
2132 		return (0);
2133 	return (c->value);
2134 }
2135 
2136 const char *
comm_string(u_int ncomm)2137 comm_string(u_int ncomm)
2138 {
2139 	struct community *p;
2140 
2141 	TAILQ_FOREACH(p, &community_list, link)
2142 		if (p->value == ncomm)
2143 			return (p->string);
2144 	return (NULL);
2145 }
2146 
2147 /*
2148  * Delete all communities allocated by a module
2149  */
2150 static void
comm_flush(struct lmodule * mod)2151 comm_flush(struct lmodule *mod)
2152 {
2153 	struct community *p, *p1;
2154 
2155 	p = TAILQ_FIRST(&community_list);
2156 	while (p != NULL) {
2157 		p1 = TAILQ_NEXT(p, link);
2158 		if (p->owner == mod) {
2159 			free(p->string);
2160 			TAILQ_REMOVE(&community_list, p, link);
2161 			free(p);
2162 		}
2163 		p = p1;
2164 	}
2165 }
2166 
2167 /*
2168  * Request ID handling.
2169  *
2170  * Allocate a new range of request ids. Use a first fit algorithm.
2171  */
2172 u_int
reqid_allocate(int size,struct lmodule * mod)2173 reqid_allocate(int size, struct lmodule *mod)
2174 {
2175 	u_int type;
2176 	struct idrange *r, *r1;
2177 
2178 	if (size <= 0 || size > INT32_MAX) {
2179 		syslog(LOG_CRIT, "%s: size out of range: %d", __func__, size);
2180 		return (0);
2181 	}
2182 	/* allocate a type id */
2183 	do {
2184 		if ((type = next_idrange++) == UINT_MAX)
2185 			next_idrange = 1;
2186 		TAILQ_FOREACH(r, &idrange_list, link)
2187 			if (r->type == type)
2188 				break;
2189 	} while(r != NULL);
2190 
2191 	/* find a range */
2192 	if (TAILQ_EMPTY(&idrange_list))
2193 		r = NULL;
2194 	else {
2195 		r = TAILQ_FIRST(&idrange_list);
2196 		if (r->base < size) {
2197 			while((r1 = TAILQ_NEXT(r, link)) != NULL) {
2198 				if (r1->base - (r->base + r->size) >= size)
2199 					break;
2200 				r = r1;
2201 			}
2202 			r = r1;
2203 		}
2204 		if (r == NULL) {
2205 			r1 = TAILQ_LAST(&idrange_list, idrange_list);
2206 			if (INT32_MAX - size + 1 < r1->base + r1->size) {
2207 				syslog(LOG_ERR, "out of id ranges (%u)", size);
2208 				return (0);
2209 			}
2210 		}
2211 	}
2212 
2213 	/* allocate structure */
2214 	if ((r1 = malloc(sizeof(struct idrange))) == NULL) {
2215 		syslog(LOG_ERR, "%s: %m", __FUNCTION__);
2216 		return (0);
2217 	}
2218 
2219 	r1->type = type;
2220 	r1->size = size;
2221 	r1->owner = mod;
2222 	if (TAILQ_EMPTY(&idrange_list) || r == TAILQ_FIRST(&idrange_list)) {
2223 		r1->base = 0;
2224 		TAILQ_INSERT_HEAD(&idrange_list, r1, link);
2225 	} else if (r == NULL) {
2226 		r = TAILQ_LAST(&idrange_list, idrange_list);
2227 		r1->base = r->base + r->size;
2228 		TAILQ_INSERT_TAIL(&idrange_list, r1, link);
2229 	} else {
2230 		r = TAILQ_PREV(r, idrange_list, link);
2231 		r1->base = r->base + r->size;
2232 		TAILQ_INSERT_AFTER(&idrange_list, r, r1, link);
2233 	}
2234 	r1->next = r1->base;
2235 
2236 	return (type);
2237 }
2238 
2239 int32_t
reqid_next(u_int type)2240 reqid_next(u_int type)
2241 {
2242 	struct idrange *r;
2243 	int32_t id;
2244 
2245 	TAILQ_FOREACH(r, &idrange_list, link)
2246 		if (r->type == type)
2247 			break;
2248 	if (r == NULL) {
2249 		syslog(LOG_CRIT, "wrong idrange type");
2250 		abort();
2251 	}
2252 	if ((id = r->next++) == r->base + (r->size - 1))
2253 		r->next = r->base;
2254 	return (id);
2255 }
2256 
2257 int32_t
reqid_base(u_int type)2258 reqid_base(u_int type)
2259 {
2260 	struct idrange *r;
2261 
2262 	TAILQ_FOREACH(r, &idrange_list, link)
2263 		if (r->type == type)
2264 			return (r->base);
2265 	syslog(LOG_CRIT, "wrong idrange type");
2266 	abort();
2267 }
2268 
2269 u_int
reqid_type(int32_t reqid)2270 reqid_type(int32_t reqid)
2271 {
2272 	struct idrange *r;
2273 
2274 	TAILQ_FOREACH(r, &idrange_list, link)
2275 		if (reqid >= r->base && reqid <= r->base + (r->size - 1))
2276 			return (r->type);
2277 	return (0);
2278 }
2279 
2280 int
reqid_istype(int32_t reqid,u_int type)2281 reqid_istype(int32_t reqid, u_int type)
2282 {
2283 	return (reqid_type(reqid) == type);
2284 }
2285 
2286 /*
2287  * Delete all communities allocated by a module
2288  */
2289 static void
reqid_flush(struct lmodule * mod)2290 reqid_flush(struct lmodule *mod)
2291 {
2292 	struct idrange *p, *p1;
2293 
2294 	p = TAILQ_FIRST(&idrange_list);
2295 	while (p != NULL) {
2296 		p1 = TAILQ_NEXT(p, link);
2297 		if (p->owner == mod) {
2298 			TAILQ_REMOVE(&idrange_list, p, link);
2299 			free(p);
2300 		}
2301 		p = p1;
2302 	}
2303 }
2304 
2305 /*
2306  * Merge the given tree for the given module into the main tree.
2307  */
2308 static int
compare_node(const void * v1,const void * v2)2309 compare_node(const void *v1, const void *v2)
2310 {
2311 	const struct snmp_node *n1 = v1;
2312 	const struct snmp_node *n2 = v2;
2313 
2314 	return (asn_compare_oid(&n1->oid, &n2->oid));
2315 }
2316 static int
tree_merge(const struct snmp_node * ntree,u_int nsize,struct lmodule * mod)2317 tree_merge(const struct snmp_node *ntree, u_int nsize, struct lmodule *mod)
2318 {
2319 	struct snmp_node *xtree;
2320 	u_int i;
2321 
2322 	xtree = realloc(tree, sizeof(*tree) * (tree_size + nsize));
2323 	if (xtree == NULL) {
2324 		syslog(LOG_ERR, "tree_merge: %m");
2325 		return (-1);
2326 	}
2327 	tree = xtree;
2328 	memcpy(&tree[tree_size], ntree, sizeof(*tree) * nsize);
2329 
2330 	for (i = 0; i < nsize; i++)
2331 		tree[tree_size + i].tree_data = mod;
2332 
2333 	tree_size += nsize;
2334 
2335 	qsort(tree, tree_size, sizeof(tree[0]), compare_node);
2336 
2337 	return (0);
2338 }
2339 
2340 /*
2341  * Remove all nodes belonging to the loadable module
2342  */
2343 static void
tree_unmerge(struct lmodule * mod)2344 tree_unmerge(struct lmodule *mod)
2345 {
2346 	u_int s, d;
2347 
2348 	for(s = d = 0; s < tree_size; s++)
2349 		if (tree[s].tree_data != mod) {
2350 			if (s != d)
2351 				tree[d] = tree[s];
2352 			d++;
2353 		}
2354 	tree_size = d;
2355 }
2356 
2357 /*
2358  * Loadable modules
2359  */
2360 struct lmodule *
lm_load(const char * path,const char * section)2361 lm_load(const char *path, const char *section)
2362 {
2363 	struct lmodule *m;
2364 	int err;
2365 	int i;
2366 	char *av[MAX_MOD_ARGS + 1];
2367 	int ac;
2368 	u_int u;
2369 
2370 	if ((m = malloc(sizeof(*m))) == NULL) {
2371 		syslog(LOG_ERR, "lm_load: %m");
2372 		return (NULL);
2373 	}
2374 	m->handle = NULL;
2375 	m->flags = 0;
2376 	strlcpy(m->section, section, sizeof(m->section));
2377 
2378 	if ((m->path = strdup(path)) == NULL) {
2379 		syslog(LOG_ERR, "lm_load: %m");
2380 		goto err;
2381 	}
2382 
2383 	/*
2384 	 * Make index
2385 	 */
2386 	m->index.subs[0] = strlen(section);
2387 	m->index.len = m->index.subs[0] + 1;
2388 	for (u = 0; u < m->index.subs[0]; u++)
2389 		m->index.subs[u + 1] = section[u];
2390 
2391 	/*
2392 	 * Load the object file and locate the config structure
2393 	 */
2394 	if ((m->handle = dlopen(m->path, RTLD_NOW|RTLD_GLOBAL)) == NULL) {
2395 		syslog(LOG_ERR, "lm_load: open %s", dlerror());
2396 		goto err;
2397 	}
2398 
2399 	if ((m->config = dlsym(m->handle, "config")) == NULL) {
2400 		syslog(LOG_ERR, "lm_load: no 'config' symbol %s", dlerror());
2401 		goto err;
2402 	}
2403 
2404 	/*
2405 	 * Insert it into the right place
2406 	 */
2407 	INSERT_OBJECT_OID(m, &lmodules);
2408 
2409 	/* preserve order */
2410 	if (community == COMM_INITIALIZE) {
2411 		m->flags |= LM_ONSTARTLIST;
2412 		TAILQ_INSERT_TAIL(&modules_start, m, start);
2413 	}
2414 
2415 	/*
2416 	 * make the argument vector.
2417 	 */
2418 	ac = 0;
2419 	for (i = 0; i < nprogargs; i++) {
2420 		if (strlen(progargs[i]) >= strlen(section) + 1 &&
2421 		    strncmp(progargs[i], section, strlen(section)) == 0 &&
2422 		    progargs[i][strlen(section)] == ':') {
2423 			if (ac == MAX_MOD_ARGS) {
2424 				syslog(LOG_WARNING, "too many arguments for "
2425 				    "module '%s", section);
2426 				break;
2427 			}
2428 			av[ac++] = &progargs[i][strlen(section)+1];
2429 		}
2430 	}
2431 	av[ac] = NULL;
2432 
2433 	/*
2434 	 * Run the initialization function
2435 	 */
2436 	if ((err = (*m->config->init)(m, ac, av)) != 0) {
2437 		syslog(LOG_ERR, "lm_load: init failed: %d", err);
2438 		TAILQ_REMOVE(&lmodules, m, link);
2439 		goto err;
2440 	}
2441 
2442 	return (m);
2443 
2444   err:
2445 	if ((m->flags & LM_ONSTARTLIST) != 0)
2446 		TAILQ_REMOVE(&modules_start, m, start);
2447 	if (m->handle)
2448 		dlclose(m->handle);
2449 	free(m->path);
2450 	free(m);
2451 	return (NULL);
2452 }
2453 
2454 /*
2455  * Start a module
2456  */
2457 void
lm_start(struct lmodule * mod)2458 lm_start(struct lmodule *mod)
2459 {
2460 	const struct lmodule *m;
2461 
2462 	/*
2463 	 * Merge tree. If this fails, unload the module.
2464 	 */
2465 	if (tree_merge(mod->config->tree, mod->config->tree_size, mod)) {
2466 		lm_unload(mod);
2467 		return;
2468 	}
2469 
2470 	/*
2471 	 * Read configuration
2472 	 */
2473 	if (read_config(config_file, mod)) {
2474 		syslog(LOG_ERR, "error in config file");
2475 		lm_unload(mod);
2476 		return;
2477 	}
2478 	if (mod->config->start)
2479 		(*mod->config->start)();
2480 
2481 	mod->flags |= LM_STARTED;
2482 
2483 	/*
2484 	 * Inform other modules
2485 	 */
2486 	TAILQ_FOREACH(m, &lmodules, link)
2487 		if (m->config->loading)
2488 			(*m->config->loading)(mod, 1);
2489 }
2490 
2491 
2492 /*
2493  * Unload a module.
2494  */
2495 void
lm_unload(struct lmodule * m)2496 lm_unload(struct lmodule *m)
2497 {
2498 	int err;
2499 	const struct lmodule *mod;
2500 
2501 	TAILQ_REMOVE(&lmodules, m, link);
2502 	if (m->flags & LM_ONSTARTLIST)
2503 		TAILQ_REMOVE(&modules_start, m, start);
2504 	tree_unmerge(m);
2505 
2506 	if ((m->flags & LM_STARTED) && m->config->fini &&
2507 	    (err = (*m->config->fini)()) != 0)
2508 		syslog(LOG_WARNING, "lm_unload(%s): fini %d", m->section, err);
2509 
2510 	comm_flush(m);
2511 	reqid_flush(m);
2512 	timer_flush(m);
2513 	fd_flush(m);
2514 
2515 	dlclose(m->handle);
2516 	free(m->path);
2517 
2518 	/*
2519 	 * Inform other modules
2520 	 */
2521 	TAILQ_FOREACH(mod, &lmodules, link)
2522 		if (mod->config->loading)
2523 			(*mod->config->loading)(m, 0);
2524 
2525 	free(m);
2526 }
2527 
2528 /*
2529  * Register an object resource and return the index (or 0 on failures)
2530  */
2531 u_int
or_register(const struct asn_oid * or,const char * descr,struct lmodule * mod)2532 or_register(const struct asn_oid *or, const char *descr, struct lmodule *mod)
2533 {
2534 	struct objres *objres, *or1;
2535 	u_int idx;
2536 
2537 	/* find a free index */
2538 	idx = 1;
2539 	for (objres = TAILQ_FIRST(&objres_list);
2540 	     objres != NULL;
2541 	     objres = TAILQ_NEXT(objres, link)) {
2542 		if ((or1 = TAILQ_NEXT(objres, link)) == NULL ||
2543 		    or1->index > objres->index + 1) {
2544 			idx = objres->index + 1;
2545 			break;
2546 		}
2547 	}
2548 
2549 	if ((objres = malloc(sizeof(*objres))) == NULL)
2550 		return (0);
2551 
2552 	objres->index = idx;
2553 	objres->oid = *or;
2554 	strlcpy(objres->descr, descr, sizeof(objres->descr));
2555 	objres->uptime = (uint32_t)(get_ticks() - start_tick);
2556 	objres->module = mod;
2557 
2558 	INSERT_OBJECT_INT(objres, &objres_list);
2559 
2560 	systemg.or_last_change = objres->uptime;
2561 
2562 	return (idx);
2563 }
2564 
2565 void
or_unregister(u_int idx)2566 or_unregister(u_int idx)
2567 {
2568 	struct objres *objres;
2569 
2570 	TAILQ_FOREACH(objres, &objres_list, link)
2571 		if (objres->index == idx) {
2572 			TAILQ_REMOVE(&objres_list, objres, link);
2573 			free(objres);
2574 			return;
2575 		}
2576 }
2577 
2578 /*
2579  * RFC 3414 User-based Security Model support
2580  */
2581 
2582 struct snmpd_usmstat *
bsnmpd_get_usm_stats(void)2583 bsnmpd_get_usm_stats(void)
2584 {
2585 	return (&snmpd_usmstats);
2586 }
2587 
2588 void
bsnmpd_reset_usm_stats(void)2589 bsnmpd_reset_usm_stats(void)
2590 {
2591 	memset(&snmpd_usmstats, 0, sizeof(snmpd_usmstats));
2592 }
2593 
2594 struct usm_user *
usm_first_user(void)2595 usm_first_user(void)
2596 {
2597 	return (SLIST_FIRST(&usm_userlist));
2598 }
2599 
2600 struct usm_user *
usm_next_user(struct usm_user * uuser)2601 usm_next_user(struct usm_user *uuser)
2602 {
2603 	if (uuser == NULL)
2604 		return (NULL);
2605 
2606 	return (SLIST_NEXT(uuser, up));
2607 }
2608 
2609 struct usm_user *
usm_find_user(uint8_t * engine,uint32_t elen,char * uname)2610 usm_find_user(uint8_t *engine, uint32_t elen, char *uname)
2611 {
2612 	struct usm_user *uuser;
2613 
2614 	SLIST_FOREACH(uuser, &usm_userlist, up)
2615 		if (uuser->user_engine_len == elen &&
2616 		    memcmp(uuser->user_engine_id, engine, elen) == 0 &&
2617 		    strlen(uuser->suser.sec_name) == strlen(uname) &&
2618 		    strcmp(uuser->suser.sec_name, uname) == 0)
2619 			break;
2620 
2621 	return (uuser);
2622 }
2623 
2624 static int
usm_compare_user(struct usm_user * u1,struct usm_user * u2)2625 usm_compare_user(struct usm_user *u1, struct usm_user *u2)
2626 {
2627 	uint32_t i;
2628 
2629 	if (u1->user_engine_len < u2->user_engine_len)
2630 		return (-1);
2631 	if (u1->user_engine_len > u2->user_engine_len)
2632 		return (1);
2633 
2634 	for (i = 0; i < u1->user_engine_len; i++) {
2635 		if (u1->user_engine_id[i] < u2->user_engine_id[i])
2636 			return (-1);
2637 		if (u1->user_engine_id[i] > u2->user_engine_id[i])
2638 			return (1);
2639 	}
2640 
2641 	if (strlen(u1->suser.sec_name) < strlen(u2->suser.sec_name))
2642 		return (-1);
2643 	if (strlen(u1->suser.sec_name) > strlen(u2->suser.sec_name))
2644 		return (1);
2645 
2646 	for (i = 0; i < strlen(u1->suser.sec_name); i++) {
2647 		if (u1->suser.sec_name[i] < u2->suser.sec_name[i])
2648 			return (-1);
2649 		if (u1->suser.sec_name[i] > u2->suser.sec_name[i])
2650 			return (1);
2651 	}
2652 
2653 	return (0);
2654 }
2655 
2656 struct usm_user *
usm_new_user(uint8_t * eid,uint32_t elen,char * uname)2657 usm_new_user(uint8_t *eid, uint32_t elen, char *uname)
2658 {
2659 	int cmp;
2660 	struct usm_user *uuser, *temp, *prev;
2661 
2662 	for (uuser = usm_first_user(); uuser != NULL;
2663 	    (uuser = usm_next_user(uuser))) {
2664 		if (uuser->user_engine_len == elen &&
2665 		    strlen(uname) == strlen(uuser->suser.sec_name) &&
2666 		    strcmp(uname, uuser->suser.sec_name) == 0 &&
2667 		    memcmp(eid, uuser->user_engine_id, elen) == 0)
2668 			return (NULL);
2669 	}
2670 
2671 	if ((uuser = (struct usm_user *)malloc(sizeof(*uuser))) == NULL)
2672 		return (NULL);
2673 
2674 	memset(uuser, 0, sizeof(*uuser));
2675 	strlcpy(uuser->suser.sec_name, uname, SNMP_ADM_STR32_SIZ);
2676 	memcpy(uuser->user_engine_id, eid, elen);
2677 	uuser->user_engine_len = elen;
2678 
2679 	if ((prev = SLIST_FIRST(&usm_userlist)) == NULL ||
2680 	    usm_compare_user(uuser, prev) < 0) {
2681 		SLIST_INSERT_HEAD(&usm_userlist, uuser, up);
2682 		return (uuser);
2683 	}
2684 
2685 	SLIST_FOREACH(temp, &usm_userlist, up) {
2686 		if ((cmp = usm_compare_user(uuser, temp)) <= 0)
2687 			break;
2688 		prev = temp;
2689 	}
2690 
2691 	if (temp == NULL || cmp < 0)
2692 		SLIST_INSERT_AFTER(prev, uuser, up);
2693 	else if (cmp > 0)
2694 		SLIST_INSERT_AFTER(temp, uuser, up);
2695 	else {
2696 		syslog(LOG_ERR, "User %s exists", uuser->suser.sec_name);
2697 		free(uuser);
2698 		return (NULL);
2699 	}
2700 
2701 	return (uuser);
2702 }
2703 
2704 void
usm_delete_user(struct usm_user * uuser)2705 usm_delete_user(struct usm_user *uuser)
2706 {
2707 	SLIST_REMOVE(&usm_userlist, uuser, usm_user, up);
2708 	free(uuser);
2709 }
2710 
2711 void
usm_flush_users(void)2712 usm_flush_users(void)
2713 {
2714 	struct usm_user *uuser;
2715 
2716 	while ((uuser = SLIST_FIRST(&usm_userlist)) != NULL) {
2717 		SLIST_REMOVE_HEAD(&usm_userlist, up);
2718 		free(uuser);
2719 	}
2720 
2721 	SLIST_INIT(&usm_userlist);
2722 }
2723 
2724 /*
2725  * RFC 3415 View-based Access Control Model support
2726  */
2727 struct vacm_user *
vacm_first_user(void)2728 vacm_first_user(void)
2729 {
2730 	return (SLIST_FIRST(&vacm_userlist));
2731 }
2732 
2733 struct vacm_user *
vacm_next_user(struct vacm_user * vuser)2734 vacm_next_user(struct vacm_user *vuser)
2735 {
2736 	if (vuser == NULL)
2737 		return (NULL);
2738 
2739 	return (SLIST_NEXT(vuser, vvu));
2740 }
2741 
2742 static int
vacm_compare_user(struct vacm_user * v1,struct vacm_user * v2)2743 vacm_compare_user(struct vacm_user *v1, struct vacm_user *v2)
2744 {
2745 	uint32_t i;
2746 
2747 	if (v1->sec_model < v2->sec_model)
2748 		return (-1);
2749 	if (v1->sec_model > v2->sec_model)
2750 		return (1);
2751 
2752 	if (strlen(v1->secname) < strlen(v2->secname))
2753 		return (-1);
2754 	if (strlen(v1->secname) > strlen(v2->secname))
2755 		return (1);
2756 
2757 	for (i = 0; i < strlen(v1->secname); i++) {
2758 		if (v1->secname[i] < v2->secname[i])
2759 			return (-1);
2760 		if (v1->secname[i] > v2->secname[i])
2761 			return (1);
2762 	}
2763 
2764 	return (0);
2765 }
2766 
2767 struct vacm_user *
vacm_new_user(int32_t smodel,char * uname)2768 vacm_new_user(int32_t smodel, char *uname)
2769 {
2770 	int cmp;
2771 	struct vacm_user *user, *temp, *prev;
2772 
2773 	SLIST_FOREACH(user, &vacm_userlist, vvu)
2774 		if (strcmp(uname, user->secname) == 0 &&
2775 		    smodel == user->sec_model)
2776 			return (NULL);
2777 
2778 	if ((user = (struct vacm_user *)malloc(sizeof(*user))) == NULL)
2779 		return (NULL);
2780 
2781 	memset(user, 0, sizeof(*user));
2782 	user->group = &vacm_default_group;
2783 	SLIST_INSERT_HEAD(&vacm_default_group.group_users, user, vvg);
2784 	user->sec_model = smodel;
2785 	strlcpy(user->secname, uname, sizeof(user->secname));
2786 
2787 	if ((prev = SLIST_FIRST(&vacm_userlist)) == NULL ||
2788 	    vacm_compare_user(user, prev) < 0) {
2789 		SLIST_INSERT_HEAD(&vacm_userlist, user, vvu);
2790 		return (user);
2791 	}
2792 
2793 	SLIST_FOREACH(temp, &vacm_userlist, vvu) {
2794 		if ((cmp = vacm_compare_user(user, temp)) <= 0)
2795 			break;
2796 		prev = temp;
2797 	}
2798 
2799 	if (temp == NULL || cmp < 0)
2800 		SLIST_INSERT_AFTER(prev, user, vvu);
2801 	else if (cmp > 0)
2802 		SLIST_INSERT_AFTER(temp, user, vvu);
2803 	else {
2804 		syslog(LOG_ERR, "User %s exists", user->secname);
2805 		free(user);
2806 		return (NULL);
2807 	}
2808 
2809 	return (user);
2810 }
2811 
2812 int
vacm_delete_user(struct vacm_user * user)2813 vacm_delete_user(struct vacm_user *user)
2814 {
2815 	if (user->group != NULL && user->group != &vacm_default_group) {
2816 		SLIST_REMOVE(&user->group->group_users, user, vacm_user, vvg);
2817 		if (SLIST_EMPTY(&user->group->group_users)) {
2818 			SLIST_REMOVE(&vacm_grouplist, user->group,
2819 			    vacm_group, vge);
2820 			free(user->group);
2821 		}
2822 	}
2823 
2824 	SLIST_REMOVE(&vacm_userlist, user, vacm_user, vvu);
2825 	free(user);
2826 
2827 	return (0);
2828 }
2829 
2830 int
vacm_user_set_group(struct vacm_user * user,u_char * octets,u_int len)2831 vacm_user_set_group(struct vacm_user *user, u_char *octets, u_int len)
2832 {
2833 	struct vacm_group *group;
2834 
2835 	if (len >= SNMP_ADM_STR32_SIZ)
2836 		return (-1);
2837 
2838 	SLIST_FOREACH(group, &vacm_grouplist, vge)
2839 		if (strlen(group->groupname) == len &&
2840 		    memcmp(octets, group->groupname, len) == 0)
2841 			break;
2842 
2843 	if (group == NULL) {
2844 		if ((group = (struct vacm_group *)malloc(sizeof(*group))) == NULL)
2845 			return (-1);
2846 		memset(group, 0, sizeof(*group));
2847 		memcpy(group->groupname, octets, len);
2848 		group->groupname[len] = '\0';
2849 		SLIST_INSERT_HEAD(&vacm_grouplist, group, vge);
2850 	}
2851 
2852 	SLIST_REMOVE(&user->group->group_users, user, vacm_user, vvg);
2853 	SLIST_INSERT_HEAD(&group->group_users, user, vvg);
2854 	user->group = group;
2855 
2856 	return (0);
2857 }
2858 
2859 void
vacm_groups_init(void)2860 vacm_groups_init(void)
2861 {
2862 	SLIST_INSERT_HEAD(&vacm_grouplist, &vacm_default_group, vge);
2863 }
2864 
2865 struct vacm_access *
vacm_first_access_rule(void)2866 vacm_first_access_rule(void)
2867 {
2868 	return (TAILQ_FIRST(&vacm_accesslist));
2869 }
2870 
2871 struct vacm_access *
vacm_next_access_rule(struct vacm_access * acl)2872 vacm_next_access_rule(struct vacm_access *acl)
2873 {
2874 	if (acl == NULL)
2875 		return (NULL);
2876 
2877 	return (TAILQ_NEXT(acl, vva));
2878 }
2879 
2880 static int
vacm_compare_access_rule(struct vacm_access * v1,struct vacm_access * v2)2881 vacm_compare_access_rule(struct vacm_access *v1, struct vacm_access *v2)
2882 {
2883 	uint32_t i;
2884 
2885 	if (strlen(v1->group->groupname) < strlen(v2->group->groupname))
2886 		return (-1);
2887 	if (strlen(v1->group->groupname) > strlen(v2->group->groupname))
2888 		return (1);
2889 
2890 	for (i = 0; i < strlen(v1->group->groupname); i++) {
2891 		if (v1->group->groupname[i] < v2->group->groupname[i])
2892 			return (-1);
2893 		if (v1->group->groupname[i] > v2->group->groupname[i])
2894 			return (1);
2895 	}
2896 
2897 	if (strlen(v1->ctx_prefix) < strlen(v2->ctx_prefix))
2898 		return (-1);
2899 	if (strlen(v1->ctx_prefix) > strlen(v2->ctx_prefix))
2900 		return (1);
2901 
2902 	for (i = 0; i < strlen(v1->ctx_prefix); i++) {
2903 		if (v1->ctx_prefix[i] < v2->ctx_prefix[i])
2904 			return (-1);
2905 		if (v1->ctx_prefix[i] > v2->ctx_prefix[i])
2906 			return (1);
2907 	}
2908 
2909 	if (v1->sec_model < v2->sec_model)
2910 		return (-1);
2911 	if (v1->sec_model > v2->sec_model)
2912 		return (1);
2913 
2914 	if (v1->sec_level < v2->sec_level)
2915 		return (-1);
2916 	if (v1->sec_level > v2->sec_level)
2917 		return (1);
2918 
2919 	return (0);
2920 }
2921 
2922 struct vacm_access *
vacm_new_access_rule(char * gname,char * cprefix,int32_t smodel,int32_t slevel)2923 vacm_new_access_rule(char *gname, char *cprefix, int32_t smodel, int32_t slevel)
2924 {
2925 	struct vacm_group *group;
2926 	struct vacm_access *acl, *temp;
2927 
2928 	TAILQ_FOREACH(acl, &vacm_accesslist, vva) {
2929 		if (acl->group == NULL)
2930 			continue;
2931 		if (strcmp(gname, acl->group->groupname) == 0 &&
2932 		    strcmp(cprefix, acl->ctx_prefix) == 0 &&
2933 		    acl->sec_model == smodel && acl->sec_level == slevel)
2934 			return (NULL);
2935 	}
2936 
2937 	/* Make sure the group exists */
2938 	SLIST_FOREACH(group, &vacm_grouplist, vge)
2939 		if (strcmp(gname, group->groupname) == 0)
2940 			break;
2941 
2942 	if (group == NULL)
2943 		return (NULL);
2944 
2945 	if ((acl = (struct vacm_access *)malloc(sizeof(*acl))) == NULL)
2946 		return (NULL);
2947 
2948 	memset(acl, 0, sizeof(*acl));
2949 	acl->group = group;
2950 	strlcpy(acl->ctx_prefix, cprefix, sizeof(acl->ctx_prefix));
2951 	acl->sec_model = smodel;
2952 	acl->sec_level = slevel;
2953 
2954 	if ((temp = TAILQ_FIRST(&vacm_accesslist)) == NULL ||
2955 	    vacm_compare_access_rule(acl, temp) < 0) {
2956 		TAILQ_INSERT_HEAD(&vacm_accesslist, acl, vva);
2957 		return (acl);
2958 	}
2959 
2960 	TAILQ_FOREACH(temp, &vacm_accesslist, vva)
2961 		if (vacm_compare_access_rule(acl, temp) < 0) {
2962 		    	TAILQ_INSERT_BEFORE(temp, acl, vva);
2963 			return (acl);
2964 		}
2965 
2966 	TAILQ_INSERT_TAIL(&vacm_accesslist, acl, vva);
2967 
2968 	return (acl);
2969 }
2970 
2971 int
vacm_delete_access_rule(struct vacm_access * acl)2972 vacm_delete_access_rule(struct vacm_access *acl)
2973 {
2974 	TAILQ_REMOVE(&vacm_accesslist, acl, vva);
2975 	free(acl);
2976 
2977 	return (0);
2978 }
2979 
2980 struct vacm_view *
vacm_first_view(void)2981 vacm_first_view(void)
2982 {
2983 	return (SLIST_FIRST(&vacm_viewlist));
2984 }
2985 
2986 struct vacm_view *
vacm_next_view(struct vacm_view * view)2987 vacm_next_view(struct vacm_view *view)
2988 {
2989 	if (view == NULL)
2990 		return (NULL);
2991 
2992 	return (SLIST_NEXT(view, vvl));
2993 }
2994 
2995 static int
vacm_compare_view(struct vacm_view * v1,struct vacm_view * v2)2996 vacm_compare_view(struct vacm_view *v1, struct vacm_view *v2)
2997 {
2998 	uint32_t i;
2999 
3000 	if (strlen(v1->viewname) < strlen(v2->viewname))
3001 		return (-1);
3002 	if (strlen(v1->viewname) > strlen(v2->viewname))
3003 		return (1);
3004 
3005 	for (i = 0; i < strlen(v1->viewname); i++) {
3006 		if (v1->viewname[i] < v2->viewname[i])
3007 			return (-1);
3008 		if (v1->viewname[i] > v2->viewname[i])
3009 			return (1);
3010 	}
3011 
3012 	return (asn_compare_oid(&v1->subtree, &v2->subtree));
3013 }
3014 
3015 struct vacm_view *
vacm_new_view(char * vname,struct asn_oid * oid)3016 vacm_new_view(char *vname, struct asn_oid *oid)
3017 {
3018 	int cmp;
3019 	struct vacm_view *view, *temp, *prev;
3020 
3021 	SLIST_FOREACH(view, &vacm_viewlist, vvl)
3022 		if (strcmp(vname, view->viewname) == 0)
3023 			return (NULL);
3024 
3025 	if ((view = (struct vacm_view *)malloc(sizeof(*view))) == NULL)
3026 		return (NULL);
3027 
3028 	memset(view, 0, sizeof(*view));
3029 	strlcpy(view->viewname, vname, sizeof(view->viewname));
3030 	asn_append_oid(&view->subtree, oid);
3031 
3032 	if ((prev = SLIST_FIRST(&vacm_viewlist)) == NULL ||
3033 	    vacm_compare_view(view, prev) < 0) {
3034 		SLIST_INSERT_HEAD(&vacm_viewlist, view, vvl);
3035 		return (view);
3036 	}
3037 
3038 	SLIST_FOREACH(temp, &vacm_viewlist, vvl) {
3039 		if ((cmp = vacm_compare_view(view, temp)) <= 0)
3040 			break;
3041 		prev = temp;
3042 	}
3043 
3044 	if (temp == NULL || cmp < 0)
3045 		SLIST_INSERT_AFTER(prev, view, vvl);
3046 	else if (cmp > 0)
3047 		SLIST_INSERT_AFTER(temp, view, vvl);
3048 	else {
3049 		syslog(LOG_ERR, "View %s exists", view->viewname);
3050 		free(view);
3051 		return (NULL);
3052 	}
3053 
3054 	return (view);
3055 }
3056 
3057 int
vacm_delete_view(struct vacm_view * view)3058 vacm_delete_view(struct vacm_view *view)
3059 {
3060 	SLIST_REMOVE(&vacm_viewlist, view, vacm_view, vvl);
3061 	free(view);
3062 
3063 	return (0);
3064 }
3065 
3066 struct vacm_context *
vacm_first_context(void)3067 vacm_first_context(void)
3068 {
3069 	return (SLIST_FIRST(&vacm_contextlist));
3070 }
3071 
3072 struct vacm_context *
vacm_next_context(struct vacm_context * vacmctx)3073 vacm_next_context(struct vacm_context *vacmctx)
3074 {
3075 	if (vacmctx == NULL)
3076 		return (NULL);
3077 
3078 	return (SLIST_NEXT(vacmctx, vcl));
3079 }
3080 
3081 struct vacm_context *
vacm_add_context(char * ctxname,int regid)3082 vacm_add_context(char *ctxname, int regid)
3083 {
3084 	int cmp;
3085 	struct vacm_context *ctx, *temp, *prev;
3086 
3087 	SLIST_FOREACH(ctx, &vacm_contextlist, vcl)
3088 		if (strcmp(ctxname, ctx->ctxname) == 0) {
3089 			syslog(LOG_ERR, "Context %s exists", ctx->ctxname);
3090 			return (NULL);
3091 		}
3092 
3093 	if ((ctx = (struct vacm_context *)malloc(sizeof(*ctx))) == NULL)
3094 		return (NULL);
3095 
3096 	memset(ctx, 0, sizeof(*ctx));
3097 	strlcpy(ctx->ctxname, ctxname, sizeof(ctx->ctxname));
3098 	ctx->regid = regid;
3099 
3100 	if ((prev = SLIST_FIRST(&vacm_contextlist)) == NULL ||
3101 	    strlen(ctx->ctxname) < strlen(prev->ctxname) ||
3102 	    strcmp(ctx->ctxname, prev->ctxname) < 0) {
3103 		SLIST_INSERT_HEAD(&vacm_contextlist, ctx, vcl);
3104 		return (ctx);
3105 	}
3106 
3107 	SLIST_FOREACH(temp, &vacm_contextlist, vcl) {
3108 		if (strlen(ctx->ctxname) < strlen(temp->ctxname) ||
3109 		    strcmp(ctx->ctxname, temp->ctxname) < 0) {
3110 		    	cmp = -1;
3111 			break;
3112 		}
3113 		prev = temp;
3114 	}
3115 
3116 	if (temp == NULL || cmp < 0)
3117 		SLIST_INSERT_AFTER(prev, ctx, vcl);
3118 	else if (cmp > 0)
3119 		SLIST_INSERT_AFTER(temp, ctx, vcl);
3120 	else {
3121 		syslog(LOG_ERR, "Context %s exists", ctx->ctxname);
3122 		free(ctx);
3123 		return (NULL);
3124 	}
3125 
3126 	return (ctx);
3127 }
3128 
3129 void
vacm_flush_contexts(int regid)3130 vacm_flush_contexts(int regid)
3131 {
3132 	struct vacm_context *ctx, *temp;
3133 
3134 	SLIST_FOREACH_SAFE(ctx, &vacm_contextlist, vcl, temp)
3135 		if (ctx->regid == regid) {
3136 			SLIST_REMOVE(&vacm_contextlist, ctx, vacm_context, vcl);
3137 			free(ctx);
3138 		}
3139 }
3140