[mirror_frr.git] / lib / agentx.c

/* SNMP support
 * Copyright (C) 2012 Vincent Bernat <bernat@luffy.cx>
 *
 * This file is part of GNU Zebra.
 *
 * GNU Zebra is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2, or (at your option) any
 * later version.
 *
 * GNU Zebra is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; see the file COPYING; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <zebra.h>

#ifdef SNMP_AGENTX
#include <net-snmp/net-snmp-config.h>
#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/agent/net-snmp-agent-includes.h>
#include <net-snmp/agent/snmp_vars.h>

#include "command.h"
#include "smux.h"
#include "memory.h"
#include "linklist.h"
#include "version.h"
#include "lib_errors.h"

static int agentx_enabled = 0;

static struct thread_master *agentx_tm;
static struct thread *timeout_thr = NULL;
static struct list *events = NULL;

static void agentx_events_update(void);

static int agentx_timeout(struct thread *t)
{
	timeout_thr = NULL;

	snmp_timeout();
	run_alarms();
	netsnmp_check_outstanding_agent_requests();
	agentx_events_update();
	return 0;
}

static int agentx_read(struct thread *t)
{
	fd_set fds;
	struct listnode *ln = THREAD_ARG(t);
	list_delete_node(events, ln);

	FD_ZERO(&fds);
	FD_SET(THREAD_FD(t), &fds);
	snmp_read(&fds);

	netsnmp_check_outstanding_agent_requests();
	agentx_events_update();
	return 0;
}

static void agentx_events_update(void)
{
	int maxfd = 0;
	int block = 1;
	struct timeval timeout = {.tv_sec = 0, .tv_usec = 0};
	fd_set fds;
	struct listnode *ln;
	struct thread *thr;
	int fd, thr_fd;

	THREAD_OFF(timeout_thr);

	FD_ZERO(&fds);
	snmp_select_info(&maxfd, &fds, &timeout, &block);

	if (!block) {
		timeout_thr = NULL;
		thread_add_timer_tv(agentx_tm, agentx_timeout, NULL, &timeout,
				    &timeout_thr);
	}

	ln = listhead(events);
	thr = ln ? listgetdata(ln) : NULL;
	thr_fd = thr ? THREAD_FD(thr) : -1;

	/* "two-pointer" / two-list simultaneous iteration
	 * ln/thr/thr_fd point to the next existing event listener to hit while
	 * fd counts to catch up */
	for (fd = 0; fd < maxfd; fd++) {
		/* caught up */
		if (thr_fd == fd) {
			struct listnode *nextln = listnextnode(ln);
			if (!FD_ISSET(fd, &fds)) {
				thread_cancel(thr);
				list_delete_node(events, ln);
			}
			ln = nextln;
			thr = ln ? listgetdata(ln) : NULL;
			thr_fd = thr ? THREAD_FD(thr) : -1;
		}
		/* need listener, but haven't hit one where it would be */
		else if (FD_ISSET(fd, &fds)) {
			struct listnode *newln;
			thr = NULL;
			thread_add_read(agentx_tm, agentx_read, NULL, fd, &thr);
			newln = listnode_add_before(events, ln, thr);
			thr->arg = newln;
		}
	}

	/* leftover event listeners at this point have fd > maxfd, delete them
	 */
	while (ln) {
		struct listnode *nextln = listnextnode(ln);
		thread_cancel(listgetdata(ln));
		list_delete_node(events, ln);
		ln = nextln;
	}
}

/* AgentX node. */
static struct cmd_node agentx_node = {SMUX_NODE,
				      "", /* AgentX has no interface. */
				      1};

/* Logging NetSNMP messages */
static int agentx_log_callback(int major, int minor, void *serverarg,
			       void *clientarg)
{
	struct snmp_log_message *slm = (struct snmp_log_message *)serverarg;
	char *msg = XSTRDUP(MTYPE_TMP, slm->msg);
	if (msg)
		msg[strlen(msg) - 1] = '\0';
	switch (slm->priority) {
	case LOG_EMERG:
		flog_err(EC_LIB_SNMP, "snmp[emerg]: %s", msg ? msg : slm->msg);
		break;
	case LOG_ALERT:
		flog_err(EC_LIB_SNMP, "snmp[alert]: %s", msg ? msg : slm->msg);
		break;
	case LOG_CRIT:
		flog_err(EC_LIB_SNMP, "snmp[crit]: %s", msg ? msg : slm->msg);
		break;
	case LOG_ERR:
		flog_err(EC_LIB_SNMP, "snmp[err]: %s", msg ? msg : slm->msg);
		break;
	case LOG_WARNING:
		flog_warn(EC_LIB_SNMP, "snmp[warning]: %s",
			  msg ? msg : slm->msg);
		break;
	case LOG_NOTICE:
		zlog_notice("snmp[notice]: %s", msg ? msg : slm->msg);
		break;
	case LOG_INFO:
		zlog_info("snmp[info]: %s", msg ? msg : slm->msg);
		break;
	case LOG_DEBUG:
		zlog_debug("snmp[debug]: %s", msg ? msg : slm->msg);
		break;
	}
	XFREE(MTYPE_TMP, msg);
	return SNMP_ERR_NOERROR;
}

static int config_write_agentx(struct vty *vty)
{
	if (agentx_enabled)
		vty_out(vty, "agentx\n");
	return 1;
}

DEFUN (agentx_enable,
       agentx_enable_cmd,
       "agentx",
       "SNMP AgentX protocol settings\n")
{
	if (!agentx_enabled) {
		init_snmp(FRR_SMUX_NAME);
		events = list_new();
		agentx_events_update();
		agentx_enabled = 1;
	}

	return CMD_SUCCESS;
}

DEFUN (no_agentx,
       no_agentx_cmd,
       "no agentx",
       NO_STR
       "SNMP AgentX protocol settings\n")
{
	if (!agentx_enabled)
		return CMD_SUCCESS;
	vty_out(vty, "SNMP AgentX support cannot be disabled once enabled\n");
	return CMD_WARNING_CONFIG_FAILED;
}

void smux_init(struct thread_master *tm)
{
	agentx_tm = tm;

	netsnmp_enable_subagent();
	snmp_disable_log();
	snmp_enable_calllog();
	snmp_register_callback(SNMP_CALLBACK_LIBRARY, SNMP_CALLBACK_LOGGING,
			       agentx_log_callback, NULL);
	init_agent(FRR_SMUX_NAME);

	install_node(&agentx_node, config_write_agentx);
	install_element(CONFIG_NODE, &agentx_enable_cmd);
	install_element(CONFIG_NODE, &no_agentx_cmd);
}

void smux_register_mib(const char *descr, struct variable *var, size_t width,
		       int num, oid name[], size_t namelen)
{
	register_mib(descr, var, width, num, name, namelen);
}

int smux_trap(struct variable *vp, size_t vp_len, const oid *ename,
	      size_t enamelen, const oid *name, size_t namelen,
	      const oid *iname, size_t inamelen,
	      const struct trap_object *trapobj, size_t trapobjlen,
	      uint8_t sptrap)
{
	oid objid_snmptrap[] = {1, 3, 6, 1, 6, 3, 1, 1, 4, 1, 0};
	size_t objid_snmptrap_len = sizeof objid_snmptrap / sizeof(oid);
	oid notification_oid[MAX_OID_LEN];
	size_t notification_oid_len;
	unsigned int i;

	netsnmp_variable_list *notification_vars = NULL;
	if (!agentx_enabled)
		return 0;

	/* snmpTrapOID */
	oid_copy(notification_oid, ename, enamelen);
	notification_oid[enamelen] = sptrap;
	notification_oid_len = enamelen + 1;
	snmp_varlist_add_variable(&notification_vars, objid_snmptrap,
				  objid_snmptrap_len, ASN_OBJECT_ID,
				  (uint8_t *)notification_oid,
				  notification_oid_len * sizeof(oid));

	/* Provided bindings */
	for (i = 0; i < trapobjlen; i++) {
		unsigned int j;
		oid oid[MAX_OID_LEN];
		size_t oid_len, onamelen;
		uint8_t *val;
		size_t val_len;
		WriteMethod *wm = NULL;
		struct variable cvp;

		/* Make OID. */
		if (trapobj[i].namelen > 0) {
			/* Columnar object */
			onamelen = trapobj[i].namelen;
			oid_copy(oid, name, namelen);
			oid_copy(oid + namelen, trapobj[i].name, onamelen);
			oid_copy(oid + namelen + onamelen, iname, inamelen);
			oid_len = namelen + onamelen + inamelen;
		} else {
			/* Scalar object */
			onamelen = trapobj[i].namelen * (-1);
			oid_copy(oid, name, namelen);
			oid_copy(oid + namelen, trapobj[i].name, onamelen);
			oid[onamelen + namelen] = 0;
			oid_len = namelen + onamelen + 1;
		}

		/* Locate the appropriate function and type in the MIB registry.
		 */
		for (j = 0; j < vp_len; j++) {
			if (oid_compare(trapobj[i].name, onamelen, vp[j].name,
					vp[j].namelen)
			    != 0)
				continue;
			/* We found the appropriate variable in the MIB
			 * registry. */
			oid_copy(cvp.name, name, namelen);
			oid_copy(cvp.name + namelen, vp[j].name, vp[j].namelen);
			cvp.namelen = namelen + vp[j].namelen;
			cvp.type = vp[j].type;
			cvp.magic = vp[j].magic;
			cvp.acl = vp[j].acl;
			cvp.findVar = vp[j].findVar;
			/* Grab the result. */
			val = cvp.findVar(&cvp, oid, &oid_len, 1, &val_len,
					  &wm);
			if (!val)
				break;
			snmp_varlist_add_variable(&notification_vars, oid,
						  oid_len, vp[j].type, val,
						  val_len);
			break;
		}
	}


	send_v2trap(notification_vars);
	snmp_free_varbind(notification_vars);
	agentx_events_update();
	return 1;
}

#endif /* SNMP_AGENTX */
Commit	Line	Data
d6be5fb9 VB	1	/* SNMP support
	2	* Copyright (C) 2012 Vincent Bernat <bernat@luffy.cx>
	3	*
	4	* This file is part of GNU Zebra.
	5	*
	6	* GNU Zebra is free software; you can redistribute it and/or modify it
	7	* under the terms of the GNU General Public License as published by the
	8	* Free Software Foundation; either version 2, or (at your option) any
	9	* later version.
	10	*
	11	* GNU Zebra is distributed in the hope that it will be useful, but
	12	* WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* General Public License for more details.
	15	*
896014f4 DL	16	* You should have received a copy of the GNU General Public License along
	17	* with this program; see the file COPYING; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
d6be5fb9 VB	19	*/
	20
	21	#include <zebra.h>
	22
5986b66b	23	#ifdef SNMP_AGENTX
d6be5fb9 VB	24	#include <net-snmp/net-snmp-config.h>
d6be5fb9 VB	25	#include <net-snmp/net-snmp-includes.h>
56e2c5e8 DL	26	#include <net-snmp/agent/net-snmp-agent-includes.h>
56e2c5e8 DL	27	#include <net-snmp/agent/snmp_vars.h>
d6be5fb9 VB	28
	29	#include "command.h"
	30	#include "smux.h"
d11f748b	31	#include "memory.h"
56e2c5e8	32	#include "linklist.h"
ae435b19	33	#include "version.h"
220d7368	34	#include "lib_errors.h"
d6be5fb9	35
56e2c5e8 DL	36	static int agentx_enabled = 0;
	37
	38	static struct thread_master *agentx_tm;
	39	static struct thread *timeout_thr = NULL;
	40	static struct list *events = NULL;
	41
	42	static void agentx_events_update(void);
	43
d62a17ae	44	static int agentx_timeout(struct thread *t)
56e2c5e8	45	{
d62a17ae	46	timeout_thr = NULL;
56e2c5e8	47
d62a17ae	48	snmp_timeout();
	49	run_alarms();
	50	netsnmp_check_outstanding_agent_requests();
	51	agentx_events_update();
	52	return 0;
56e2c5e8 DL	53	}
56e2c5e8 DL	54
d62a17ae	55	static int agentx_read(struct thread *t)
56e2c5e8	56	{
d62a17ae	57	fd_set fds;
	58	struct listnode *ln = THREAD_ARG(t);
	59	list_delete_node(events, ln);
56e2c5e8	60
d62a17ae	61	FD_ZERO(&fds);
	62	FD_SET(THREAD_FD(t), &fds);
	63	snmp_read(&fds);
56e2c5e8	64
d62a17ae	65	netsnmp_check_outstanding_agent_requests();
	66	agentx_events_update();
	67	return 0;
56e2c5e8 DL	68	}
56e2c5e8 DL	69
d62a17ae	70	static void agentx_events_update(void)
56e2c5e8	71	{
d62a17ae	72	int maxfd = 0;
	73	int block = 1;
	74	struct timeval timeout = {.tv_sec = 0, .tv_usec = 0};
	75	fd_set fds;
	76	struct listnode *ln;
	77	struct thread *thr;
	78	int fd, thr_fd;
	79
	80	THREAD_OFF(timeout_thr);
	81
	82	FD_ZERO(&fds);
	83	snmp_select_info(&maxfd, &fds, &timeout, &block);
	84
	85	if (!block) {
	86	timeout_thr = NULL;
	87	thread_add_timer_tv(agentx_tm, agentx_timeout, NULL, &timeout,
	88	&timeout_thr);
	89	}
	90
	91	ln = listhead(events);
	92	thr = ln ? listgetdata(ln) : NULL;
	93	thr_fd = thr ? THREAD_FD(thr) : -1;
	94
	95	/* "two-pointer" / two-list simultaneous iteration
	96	* ln/thr/thr_fd point to the next existing event listener to hit while
	97	* fd counts to catch up */
	98	for (fd = 0; fd < maxfd; fd++) {
	99	/* caught up */
	100	if (thr_fd == fd) {
	101	struct listnode *nextln = listnextnode(ln);
	102	if (!FD_ISSET(fd, &fds)) {
	103	thread_cancel(thr);
	104	list_delete_node(events, ln);
	105	}
	106	ln = nextln;
	107	thr = ln ? listgetdata(ln) : NULL;
	108	thr_fd = thr ? THREAD_FD(thr) : -1;
	109	}
	110	/* need listener, but haven't hit one where it would be */
	111	else if (FD_ISSET(fd, &fds)) {
	112	struct listnode *newln;
	113	thr = NULL;
	114	thread_add_read(agentx_tm, agentx_read, NULL, fd, &thr);
	115	newln = listnode_add_before(events, ln, thr);
	116	thr->arg = newln;
	117	}
	118	}
	119
	120	/* leftover event listeners at this point have fd > maxfd, delete them
	121	*/
	122	while (ln) {
	123	struct listnode *nextln = listnextnode(ln);
	124	thread_cancel(listgetdata(ln));
	125	list_delete_node(events, ln);
	126	ln = nextln;
	127	}
56e2c5e8	128	}
d6be5fb9 VB	129
d6be5fb9 VB	130	/* AgentX node. */
d62a17ae	131	static struct cmd_node agentx_node = {SMUX_NODE,
	132	"", /* AgentX has no interface. */
	133	1};
d6be5fb9 VB	134
d6be5fb9 VB	135	/* Logging NetSNMP messages */
d62a17ae	136	static int agentx_log_callback(int major, int minor, void *serverarg,
d62a17ae	137	void *clientarg)
d6be5fb9	138	{
d62a17ae	139	struct snmp_log_message slm = (struct snmp_log_message )serverarg;
	140	char *msg = XSTRDUP(MTYPE_TMP, slm->msg);
	141	if (msg)
	142	msg[strlen(msg) - 1] = '\0';
	143	switch (slm->priority) {
	144	case LOG_EMERG:
1c50c1c0	145	flog_err(EC_LIB_SNMP, "snmp[emerg]: %s", msg ? msg : slm->msg);
d62a17ae	146	break;
d62a17ae	147	case LOG_ALERT:
1c50c1c0	148	flog_err(EC_LIB_SNMP, "snmp[alert]: %s", msg ? msg : slm->msg);
d62a17ae	149	break;
d62a17ae	150	case LOG_CRIT:
1c50c1c0	151	flog_err(EC_LIB_SNMP, "snmp[crit]: %s", msg ? msg : slm->msg);
d62a17ae	152	break;
d62a17ae	153	case LOG_ERR:
1c50c1c0	154	flog_err(EC_LIB_SNMP, "snmp[err]: %s", msg ? msg : slm->msg);
d62a17ae	155	break;
d62a17ae	156	case LOG_WARNING:
450971aa	157	flog_warn(EC_LIB_SNMP, "snmp[warning]: %s",
ade6974d	158	msg ? msg : slm->msg);
d62a17ae	159	break;
	160	case LOG_NOTICE:
	161	zlog_notice("snmp[notice]: %s", msg ? msg : slm->msg);
	162	break;
	163	case LOG_INFO:
	164	zlog_info("snmp[info]: %s", msg ? msg : slm->msg);
	165	break;
	166	case LOG_DEBUG:
	167	zlog_debug("snmp[debug]: %s", msg ? msg : slm->msg);
	168	break;
	169	}
	170	XFREE(MTYPE_TMP, msg);
	171	return SNMP_ERR_NOERROR;
d6be5fb9 VB	172	}
d6be5fb9 VB	173
d62a17ae	174	static int config_write_agentx(struct vty *vty)
d6be5fb9	175	{
d62a17ae	176	if (agentx_enabled)
	177	vty_out(vty, "agentx\n");
	178	return 1;
d6be5fb9 VB	179	}
	180
	181	DEFUN (agentx_enable,
	182	agentx_enable_cmd,
	183	"agentx",
007b0667	184	"SNMP AgentX protocol settings\n")
d6be5fb9	185	{
d62a17ae	186	if (!agentx_enabled) {
	187	init_snmp(FRR_SMUX_NAME);
	188	events = list_new();
	189	agentx_events_update();
	190	agentx_enabled = 1;
d62a17ae	191	}
5fedee18	192
d62a17ae	193	return CMD_SUCCESS;
d6be5fb9 VB	194	}
	195
	196	DEFUN (no_agentx,
	197	no_agentx_cmd,
	198	"no agentx",
	199	NO_STR
007b0667	200	"SNMP AgentX protocol settings\n")
d6be5fb9	201	{
d62a17ae	202	if (!agentx_enabled)
	203	return CMD_SUCCESS;
	204	vty_out(vty, "SNMP AgentX support cannot be disabled once enabled\n");
	205	return CMD_WARNING_CONFIG_FAILED;
d6be5fb9 VB	206	}
d6be5fb9 VB	207
d62a17ae	208	void smux_init(struct thread_master *tm)
d6be5fb9	209	{
d62a17ae	210	agentx_tm = tm;
	211
	212	netsnmp_enable_subagent();
	213	snmp_disable_log();
	214	snmp_enable_calllog();
	215	snmp_register_callback(SNMP_CALLBACK_LIBRARY, SNMP_CALLBACK_LOGGING,
	216	agentx_log_callback, NULL);
	217	init_agent(FRR_SMUX_NAME);
	218
	219	install_node(&agentx_node, config_write_agentx);
	220	install_element(CONFIG_NODE, &agentx_enable_cmd);
	221	install_element(CONFIG_NODE, &no_agentx_cmd);
d6be5fb9 VB	222	}
d6be5fb9 VB	223
d62a17ae	224	void smux_register_mib(const char descr, struct variable var, size_t width,
d62a17ae	225	int num, oid name[], size_t namelen)
d6be5fb9	226	{
d62a17ae	227	register_mib(descr, var, width, num, name, namelen);
d6be5fb9 VB	228	}
d6be5fb9 VB	229
d62a17ae	230	int smux_trap(struct variable vp, size_t vp_len, const oid ename,
	231	size_t enamelen, const oid *name, size_t namelen,
	232	const oid *iname, size_t inamelen,
	233	const struct trap_object *trapobj, size_t trapobjlen,
d7c0a89a	234	uint8_t sptrap)
d6be5fb9	235	{
d62a17ae	236	oid objid_snmptrap[] = {1, 3, 6, 1, 6, 3, 1, 1, 4, 1, 0};
	237	size_t objid_snmptrap_len = sizeof objid_snmptrap / sizeof(oid);
	238	oid notification_oid[MAX_OID_LEN];
	239	size_t notification_oid_len;
	240	unsigned int i;
	241
	242	netsnmp_variable_list *notification_vars = NULL;
	243	if (!agentx_enabled)
	244	return 0;
	245
	246	/* snmpTrapOID */
	247	oid_copy(notification_oid, ename, enamelen);
	248	notification_oid[enamelen] = sptrap;
	249	notification_oid_len = enamelen + 1;
	250	snmp_varlist_add_variable(&notification_vars, objid_snmptrap,
	251	objid_snmptrap_len, ASN_OBJECT_ID,
d7c0a89a	252	(uint8_t *)notification_oid,
d62a17ae	253	notification_oid_len * sizeof(oid));
	254
	255	/* Provided bindings */
	256	for (i = 0; i < trapobjlen; i++) {
	257	unsigned int j;
	258	oid oid[MAX_OID_LEN];
	259	size_t oid_len, onamelen;
d7c0a89a	260	uint8_t *val;
d62a17ae	261	size_t val_len;
	262	WriteMethod *wm = NULL;
	263	struct variable cvp;
	264
	265	/* Make OID. */
	266	if (trapobj[i].namelen > 0) {
	267	/* Columnar object */
	268	onamelen = trapobj[i].namelen;
	269	oid_copy(oid, name, namelen);
	270	oid_copy(oid + namelen, trapobj[i].name, onamelen);
	271	oid_copy(oid + namelen + onamelen, iname, inamelen);
	272	oid_len = namelen + onamelen + inamelen;
	273	} else {
	274	/* Scalar object */
	275	onamelen = trapobj[i].namelen * (-1);
	276	oid_copy(oid, name, namelen);
	277	oid_copy(oid + namelen, trapobj[i].name, onamelen);
	278	oid[onamelen + namelen] = 0;
	279	oid_len = namelen + onamelen + 1;
	280	}
	281
	282	/* Locate the appropriate function and type in the MIB registry.
	283	*/
	284	for (j = 0; j < vp_len; j++) {
	285	if (oid_compare(trapobj[i].name, onamelen, vp[j].name,
	286	vp[j].namelen)
	287	!= 0)
	288	continue;
	289	/* We found the appropriate variable in the MIB
	290	* registry. */
	291	oid_copy(cvp.name, name, namelen);
	292	oid_copy(cvp.name + namelen, vp[j].name, vp[j].namelen);
	293	cvp.namelen = namelen + vp[j].namelen;
	294	cvp.type = vp[j].type;
	295	cvp.magic = vp[j].magic;
	296	cvp.acl = vp[j].acl;
	297	cvp.findVar = vp[j].findVar;
	298	/* Grab the result. */
	299	val = cvp.findVar(&cvp, oid, &oid_len, 1, &val_len,
	300	&wm);
	301	if (!val)
	302	break;
	303	snmp_varlist_add_variable(&notification_vars, oid,
	304	oid_len, vp[j].type, val,
	305	val_len);
	306	break;
	307	}
b7c0d065	308	}
b7c0d065 VB	309
b7c0d065 VB	310
d62a17ae	311	send_v2trap(notification_vars);
	312	snmp_free_varbind(notification_vars);
	313	agentx_events_update();
	314	return 1;
d6be5fb9 VB	315	}
d6be5fb9 VB	316
5986b66b	317	#endif /* SNMP_AGENTX */