$NetBSD: patch-src_netstat__udp.c,v 1.2 2020/10/24 22:39:45 wiz Exp $

Add a plugin which reports the UDP summary statistics.
Useful for busyish DNS name servers.

--- src/netstat_udp.c.orig	2015-09-11 16:55:05.000000000 +0000
+++ src/netstat_udp.c
@@ -0,0 +1,157 @@
+/**
+ * collectd - src/netstat-udp.c
+ * Copyright (C) 2015  Håvard Eidnes
+ *
+ * This program 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; only version 2 of the License is applicable.
+ *
+ * This program 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; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ *
+ * Authors:
+ *   Håvard Eidnes <he at NetBSD.org>
+ **/
+
+#include "collectd.h"
+#include "utils/common/common.h"
+#include "plugin.h"
+
+#if !defined(KERNEL_NETBSD)
+# error "No applicable input method."
+#endif
+
+#include <sys/cdefs.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+
+#include <netinet/in.h>
+#include <netinet/ip_var.h>
+#include <netinet/udp.h>
+#include <netinet/udp_var.h>
+#include <netinet6/udp6_var.h>
+
+static int
+netstat_udp_init (void)
+{
+	return (0);
+} /* int netstat_udp_init */
+
+#define SUBMIT_VARS(...) \
+   plugin_dispatch_multivalue (vl, 0, DS_TYPE_DERIVE, __VA_ARGS__, NULL)
+
+static int
+netstat_udp_internal (value_list_t *vl)
+{
+	uint64_t udpstat[UDP_NSTATS];
+	uint64_t udp6stat[UDP6_NSTATS];
+	size_t size;
+	uint64_t delivered, delivered6;
+	int err;
+
+	size = sizeof(udpstat);
+	if (sysctlbyname("net.inet.udp.stats", udpstat, &size, NULL, 0) == -1) {
+		ERROR("netstat-udp plugin: could not get udp stats");
+		return -1;
+	}
+
+	delivered = udpstat[UDP_STAT_IPACKETS] -
+		udpstat[UDP_STAT_HDROPS] -
+		udpstat[UDP_STAT_BADLEN] -
+		udpstat[UDP_STAT_BADSUM] -
+		udpstat[UDP_STAT_NOPORT] -
+		udpstat[UDP_STAT_NOPORTBCAST] -
+		udpstat[UDP_STAT_FULLSOCK];
+
+	err = SUBMIT_VARS ("udp-received",
+		     (derive_t) udpstat[UDP_STAT_IPACKETS],
+		     "udp-bad-header",
+		     (derive_t) udpstat[UDP_STAT_HDROPS],
+		     "udp-bad-length",
+		     (derive_t) udpstat[UDP_STAT_BADLEN],
+		     "udp-bad-checksum",
+		     (derive_t) udpstat[UDP_STAT_BADSUM],
+		     "udp-no-port",
+		     (derive_t) udpstat[UDP_STAT_NOPORT],
+		     "udp-no-port-broadcast",
+		     (derive_t) udpstat[UDP_STAT_NOPORTBCAST],
+		     "udp-full-socket",
+		     (derive_t) udpstat[UDP_STAT_FULLSOCK],
+		     "udp-delivered",
+		     (derive_t) delivered
+		);
+	if (err != 0) {
+		ERROR("netstat-udp plugin: could not submit, err=%d\n", err);
+	}
+
+	size = sizeof(udp6stat);
+	if (sysctlbyname("net.inet6.udp6.stats", udp6stat, &size,
+			 NULL, 0) == -1) {
+		ERROR("netstat-udp plugin: could not get udp6 stats");
+		return -1;
+	}
+
+	delivered6 = udp6stat[UDP6_STAT_IPACKETS] -
+		udp6stat[UDP6_STAT_HDROPS] -
+		udp6stat[UDP6_STAT_BADLEN] -
+		udp6stat[UDP6_STAT_BADSUM] -
+		udp6stat[UDP6_STAT_NOSUM] -
+		udp6stat[UDP6_STAT_NOPORT] -
+		udp6stat[UDP6_STAT_NOPORTMCAST] -
+		udp6stat[UDP6_STAT_FULLSOCK];
+
+	err = SUBMIT_VARS ("udp6-received",
+		     (derive_t) udp6stat[UDP6_STAT_IPACKETS],
+		     "udp6-bad-header",
+		     (derive_t) udp6stat[UDP6_STAT_HDROPS],
+		     "udp6-bad-length",
+		     (derive_t) udp6stat[UDP6_STAT_BADLEN],
+		     "udp6-bad-checksum",
+		     (derive_t) udp6stat[UDP6_STAT_BADSUM],
+		     "udp6-no-checksum",
+		     (derive_t) udp6stat[UDP6_STAT_NOSUM],
+		     "udp6-no-port",
+		     (derive_t) udp6stat[UDP6_STAT_NOPORT],
+		     "udp6-no-port-multicast",
+		     (derive_t) udp6stat[UDP6_STAT_NOPORTMCAST],
+		     "udp6-full-socket",
+		     (derive_t) udp6stat[UDP6_STAT_FULLSOCK],
+		     "udp6-delivered",
+		     (derive_t) delivered6
+		);
+	if (err != 0) {
+		ERROR("netstat-udp plugin ipv6: could not submit, err=%d\n",
+		      err);
+	}
+
+	return (0);
+} /* }}} int netstat_udp_internal */
+
+static int
+netstat_udp_read (void) /* {{{ */
+{
+	value_t v[1];
+	value_list_t vl = VALUE_LIST_INIT;
+
+	vl.values = v;
+	vl.values_len = STATIC_ARRAY_SIZE (v);
+	sstrncpy (vl.host, hostname_g, sizeof (vl.host));
+	sstrncpy (vl.plugin, "netstat_udp", sizeof (vl.plugin));
+	sstrncpy (vl.type, "packets", sizeof (vl.type));
+	vl.time = cdtime ();
+
+	return (netstat_udp_internal (&vl));
+} /* }}} int netstat_udp_read */
+
+void
+module_register (void)
+{
+	plugin_register_init ("netstat_udp", netstat_udp_init);
+	plugin_register_read ("netstat_udp", netstat_udp_read);
+} /* void module_register */