ldpd: Add support for read-only snmp mib objects (excluding statistics)

Add support for read-only snmp mib objects as described in RFC 3815,
excluding statistics.

Signed-off-by: Lynne Morrison <lynne@voltanet.io>
Signed-off-by: Karen Schoener <karen@voltanet.io>

ldpd/lde.c

@@ -127,15 +127,13 @@ static struct quagga_signal_t lde_signals[] =
 void
 lde(void)
 {
-	struct thread		 thread;
-
 #ifdef HAVE_SETPROCTITLE
 	setproctitle("label decision engine");
 #endif
 	ldpd_process = PROC_LDE_ENGINE;
 	log_procname = log_procnames[PROC_LDE_ENGINE];
 
-	master = thread_master_create(NULL);
+	master = frr_init();
 
 	/* setup signal handler */
 	signal_init(master, array_size(lde_signals), lde_signals);
@@ -157,9 +155,12 @@ lde(void)
 	/* create base configuration */
 	ldeconf = config_new_empty();
 
-	/* Fetch next active thread. */
+	struct thread thread;
 	while (thread_fetch(master, &thread))
 		thread_call(&thread);
+
+	/* NOTREACHED */
+	return;
 }
 
 void
@@ -566,6 +567,9 @@ lde_dispatch_parent(struct thread *thread)
 			memcpy(&init, imsg.data, sizeof(init));
 			lde_init(&init);
 			break;
+		case IMSG_AGENTX_ENABLED:
+			ldp_agentx_enabled();
+			break;
 		case IMSG_RECONF_CONF:
 			if ((nconf = malloc(sizeof(struct ldpd_conf))) ==
 			    NULL)

ldpd/ldpd.c

@@ -86,6 +86,30 @@ static struct imsgev	*iev_lde, *iev_lde_sync;
 static pid_t		 ldpe_pid;
 static pid_t		 lde_pid;
 
+static struct frr_daemon_info ldpd_di;
+
+DEFINE_HOOK(ldp_register_mib, (struct thread_master * tm), (tm))
+
+static void ldp_load_module(const char *name)
+{
+	const char *dir;
+	dir = ldpd_di.module_path ? ldpd_di.module_path : frr_moduledir;
+	char moderr[256];
+	struct frrmod_runtime *module;
+
+	module = frrmod_load(name, dir, moderr, sizeof(moderr));
+	if (!module) {
+		fprintf(stderr, "%s: failed to load %s", __func__, name);
+		log_warnx("%s: failed to load %s", __func__, name);
+	}
+}
+
+void ldp_agentx_enabled(void)
+{
+	ldp_load_module("snmp");
+	hook_call(ldp_register_mib, master);
+}
+
 enum ldpd_process ldpd_process;
 
 #define LDP_DEFAULT_CONFIG	"ldpd.conf"
@@ -94,8 +118,6 @@ enum ldpd_process ldpd_process;
 /* Master of threads. */
 struct thread_master *master;
 
-static struct frr_daemon_info ldpd_di;
-
 /* ldpd privileges */
 static zebra_capabilities_t _caps_p [] =
 {
@@ -1343,6 +1365,9 @@ merge_global(struct ldpd_conf *conf, struct ldpd_conf *xconf)
 			ldpe_reset_ds_nbrs();
 	}
 
+	if (ldpd_process == PROC_LDP_ENGINE)
+		ldpe_set_config_change_time();
+
 	conf->flags = xconf->flags;
 }
 

ldpd/ldpd.h

@@ -161,6 +161,7 @@ enum imsg_type {
 	IMSG_RLFA_REG,
 	IMSG_RLFA_UNREG_ALL,
 	IMSG_RLFA_LABELS,
+	IMSG_AGENTX_ENABLED,
 };
 
 struct ldpd_init {
@@ -434,6 +435,7 @@ struct ldp_stats {
 	uint32_t		 labelrel_rcvd;
 	uint32_t		 labelabreq_sent;
 	uint32_t		 labelabreq_rcvd;
+
 };
 
 struct l2vpn_if {
@@ -562,6 +564,7 @@ struct ldpd_conf {
 	uint16_t		 trans_pref;
 	uint16_t		 wait_for_sync_interval;
 	int			 flags;
+	time_t			 config_change_time;
 	QOBJ_FIELDS
 };
 DECLARE_QOBJ_TYPE(ldpd_conf)
@@ -683,6 +686,8 @@ struct ctl_nbr {
 	int			 nbr_state;
 	struct ldp_stats	 stats;
 	int			 flags;
+	uint16_t		 max_pdu_len;
+	uint16_t		 hold_time_remaining;
 };
 
 struct ctl_rt {
@@ -891,4 +896,8 @@ int		 ldp_zebra_send_rlfa_labels(struct zapi_rlfa_response *
 	(__IPV6_ADDR_MC_SCOPE(a) == __IPV6_ADDR_SCOPE_INTFACELOCAL))
 #endif
 
+DECLARE_HOOK(ldp_register_mib, (struct thread_master * tm), (tm))
+
+extern void ldp_agentx_enabled(void);
+
 #endif	/* _LDPD_H_ */

ldpd/ldpe.c

@@ -33,6 +33,7 @@
 #include "memory.h"
 #include "privs.h"
 #include "sigevent.h"
+#include "libfrr.h"
 
 static void	 ldpe_shutdown(void);
 static int	 ldpe_dispatch_main(struct thread *);
@@ -103,15 +104,13 @@ char *pkt_ptr; /* packet buffer */
 void
 ldpe(void)
 {
-	struct thread		 thread;
-
 #ifdef HAVE_SETPROCTITLE
 	setproctitle("ldp engine");
 #endif
 	ldpd_process = PROC_LDP_ENGINE;
 	log_procname = log_procnames[ldpd_process];
 
-	master = thread_master_create(NULL);
+	master = frr_init();
 
 	/* setup signal handler */
 	signal_init(master, array_size(ldpe_signals), ldpe_signals);
@@ -133,9 +132,12 @@ ldpe(void)
 	/* create base configuration */
 	leconf = config_new_empty();
 
-	/* Fetch next active thread. */
+	struct thread thread;
 	while (thread_fetch(master, &thread))
 		thread_call(&thread);
+
+	/* NOTREACHED */
+	return;
 }
 
 void
@@ -387,6 +389,9 @@ ldpe_dispatch_main(struct thread *thread)
 			memcpy(&init, imsg.data, sizeof(init));
 			ldpe_init(&init);
 			break;
+		case IMSG_AGENTX_ENABLED:
+			ldp_agentx_enabled();
+			break;
 		case IMSG_CLOSE_SOCKETS:
 			af = imsg.hdr.peerid;
 
@@ -1073,3 +1078,10 @@ ldpe_check_filter_af(int af, struct ldpd_af_conf *af_conf,
 	if (strcmp(af_conf->acl_thello_accept_from, filter_name) == 0)
 		ldpe_remove_dynamic_tnbrs(af);
 }
+
+void
+ldpe_set_config_change_time(void)
+{
+	/* SNMP update time when ever there is a config change */
+	leconf->config_change_time = time(NULL);
+}

ldpd/ldpe.h

@@ -216,6 +216,7 @@ void		 ldpe_nbr_ctl(struct ctl_conn *);
 void		 ldpe_ldp_sync_ctl(struct ctl_conn *);
 void		 mapping_list_add(struct mapping_head *, struct map *);
 void		 mapping_list_clr(struct mapping_head *);
+void		 ldpe_set_config_change_time(void);
 
 /* interface.c */
 struct iface	*if_new(const char *);
@@ -266,6 +267,8 @@ struct nbr		*nbr_new(struct in_addr, int, int, union ldpd_addr *,
 			    uint32_t);
 void			 nbr_del(struct nbr *);
 struct nbr		*nbr_find_ldpid(uint32_t);
+struct nbr		*nbr_get_first_ldpid(void);
+struct nbr		*nbr_get_next_ldpid(uint32_t);
 struct nbr		*nbr_find_addr(int, union ldpd_addr *);
 struct nbr		*nbr_find_peerid(uint32_t);
 int			 nbr_adj_count(struct nbr *, int);
@@ -318,4 +321,6 @@ void	ldpe_l2vpn_exit(struct l2vpn *);
 void	ldpe_l2vpn_pw_init(struct l2vpn_pw *);
 void	ldpe_l2vpn_pw_exit(struct l2vpn_pw *);
 
+DECLARE_HOOK(ldp_nbr_state_change, (struct nbr * nbr, int old_state), (nbr, old_state))
+
 #endif	/* _LDPE_H_ */

ldpd/neighbor.c

@@ -26,6 +26,8 @@
 #include "lde.h"
 #include "log.h"
 
+DEFINE_HOOK(ldp_nbr_state_change, (struct nbr * nbr, int old_state), (nbr, old_state))
+
 static __inline int	 nbr_id_compare(const struct nbr *, const struct nbr *);
 static __inline int	 nbr_addr_compare(const struct nbr *,
 			    const struct nbr *);
@@ -158,6 +160,8 @@ nbr_fsm(struct nbr *nbr, enum nbr_event event)
 		    &nbr->id, nbr_state_name(old_state),
 		    nbr_state_name(nbr->state));
 
+		hook_call(ldp_nbr_state_change, nbr, old_state);
+
 		if (nbr->state == NBR_STA_OPER) {
 			gettimeofday(&now, NULL);
 			nbr->uptime = now.tv_sec;
@@ -354,6 +358,23 @@ nbr_find_ldpid(uint32_t lsr_id)
 	return (RB_FIND(nbr_id_head, &nbrs_by_id, &n));
 }
 
+struct nbr *
+nbr_get_first_ldpid()
+{
+	return (RB_MIN(nbr_id_head, &nbrs_by_id));
+}
+
+struct nbr *
+nbr_get_next_ldpid(uint32_t lsr_id)
+{
+	struct nbr		*nbr;
+	nbr = nbr_find_ldpid(lsr_id);
+	if (nbr)
+		return (RB_NEXT(nbr_id_head, nbr));
+	return NULL;
+}
+
+
 struct nbr *
 nbr_find_addr(int af, union ldpd_addr *addr)
 {
@@ -831,14 +852,20 @@ nbr_to_ctl(struct nbr *nbr)
 	nctl.af = nbr->af;
 	nctl.id = nbr->id;
 	nctl.laddr = nbr->laddr;
-	nctl.lport = nbr->tcp->lport;
+	nctl.lport = nbr->tcp ? nbr->tcp->lport : 0;
 	nctl.raddr = nbr->raddr;
-	nctl.rport = nbr->tcp->rport;
+	nctl.rport = nbr->tcp ? nbr->tcp->rport : 0;
 	nctl.auth_method = nbr->auth.method;
 	nctl.holdtime = nbr->keepalive;
 	nctl.nbr_state = nbr->state;
 	nctl.stats = nbr->stats;
 	nctl.flags = nbr->flags;
+	nctl.max_pdu_len = nbr->max_pdu_len;
+	if (nbr->keepalive_timer)
+		nctl.hold_time_remaining =
+		    thread_timer_remain_second(nbr->keepalive_timer);
+	else
+		nctl.hold_time_remaining = 0;
 
 	gettimeofday(&now, NULL);
 	if (nbr->state == NBR_STA_OPER) {

ldpd/subdir.am

@@ -41,6 +41,10 @@ ldpd_libldp_a_SOURCES = \
 	ldpd/util.c \
 	# end
 
+if SNMP
+module_LTLIBRARIES += ldpd/ldpd_snmp.la
+endif
+
 clippy_scan += \
 	ldpd/ldp_vty_cmds.c \
 	# end
@@ -59,3 +63,8 @@ noinst_HEADERS += \
 
 ldpd_ldpd_SOURCES = ldpd/ldpd.c
 ldpd_ldpd_LDADD = ldpd/libldp.a lib/libfrr.la $(LIBCAP)
+
+ldpd_ldpd_snmp_la_SOURCES = ldpd/ldp_snmp.c
+ldpd_ldpd_snmp_la_CFLAGS = $(WERROR) $(SNMP_CFLAGS) -std=gnu99
+ldpd_ldpd_snmp_la_LDFLAGS = -avoid-version -module -shared -export-dynamic
+ldpd_ldpd_snmp_la_LIBADD = lib/libfrrsnmp.la