Add ARP statistics to the kernel and netstat.

New counters now exist for:
requests sent
replies sent
requests received
replies received
packets received
total packets dropped due to no ARP entry
entrys timed out
Duplicate IPs seen

The new statistics are seen in the netstat command
when it is given the -s command line switch.

MFC after:	2 weeks
In collaboration with: bz

3 files changed, 47 insertions, 0 deletions

diff --git a/usr.bin/netstat/inet.c b/usr.bin/netstat/inet.c
index 8be6840..51b71c7 100644
--- a/usr.bin/netstat/inet.c
+++ b/usr.bin/netstat/inet.c
@@ -49,6 +49,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/sysctl.h>
 
 #include <net/route.h>
+#include <net/if_arp.h>
 #include <netinet/in.h>
 #include <netinet/in_systm.h>
 #include <netinet/ip.h>
@@ -871,6 +872,47 @@ ip_stats(u_long off, const char *name, int af1 __unused, int proto __unused)
 #undef p1a
 }
 
+/*
+ * Dump ARP statistics structure.
+ */
+void
+arp_stats(u_long off, const char *name, int af1 __unused, int proto __unused)
+{
+	struct arpstat arpstat, zerostat;
+	size_t len = sizeof(arpstat);
+
+	if (live) {
+		if (zflag)
+			memset(&zerostat, 0, len);
+		if (sysctlbyname("net.link.ether.arp.stats", &arpstat, &len,
+		    zflag ? &zerostat : NULL, zflag ? len : 0) < 0) {
+			warn("sysctl: net.link.ether.arp.stats");
+			return;
+		}
+	} else
+		kread(off, &arpstat, len);
+
+	printf("%s:\n", name);
+
+#define	p(f, m) if (arpstat.f || sflag <= 1) \
+    printf(m, arpstat.f, plural(arpstat.f))
+#define	p2(f, m) if (arpstat.f || sflag <= 1) \
+    printf(m, arpstat.f, pluralies(arpstat.f))
+
+	p(txrequests, "\t%lu ARP request%s sent\n");
+	p2(txreplies, "\t%lu ARP repl%s sent\n");
+	p(rxrequests, "\t%lu ARP request%s received\n");
+	p2(rxreplies, "\t%lu ARP repl%s received\n");
+	p(received, "\t%lu ARP packet%s received\n");
+	p(dropped, "\t%lu total packet%s dropped due to no ARP entry\n");
+	p(timeouts, "\t%lu ARP entry%s timed out\n");
+	p(dupips, "\t%lu Duplicate IP%s seen\n");
+#undef p
+#undef p2
+}
+
+
+
 static	const char *icmpnames[ICMP_MAXTYPE + 1] = {
 	"echo reply",			/* RFC 792 */
 	"#1",
diff --git a/usr.bin/netstat/main.c b/usr.bin/netstat/main.c
index 8b25ff5..ebbe1d2 100644
--- a/usr.bin/netstat/main.c
+++ b/usr.bin/netstat/main.c
@@ -184,6 +184,8 @@ static struct nlist nl[] = {
 	{ .n_name = "_sctpstat" },
 #define	N_MFCTABLESIZE	54
 	{ .n_name = "_mfctablesize" },
+#define N_ARPSTAT       55
+	{ .n_name = "_arpstat" },
 	{ .n_name = NULL },
 };
 
@@ -232,6 +234,8 @@ struct protox {
 	  carp_stats,	NULL,		"carp",	1,	0 },
 	{ -1,		N_PFSYNCSTAT,	1,	NULL,
 	  pfsync_stats,	NULL,		"pfsync", 1,	0 },
+	{ -1,		N_ARPSTAT,	1,	NULL,
+	  arp_stats,	NULL,		"arp", 1,	0 },
 	{ -1,		-1,		0,	NULL,
 	  NULL,		NULL,		NULL,	0,	0 }
 };
diff --git a/usr.bin/netstat/netstat.h b/usr.bin/netstat/netstat.h
index 483bd6c..f834495 100644
--- a/usr.bin/netstat/netstat.h
+++ b/usr.bin/netstat/netstat.h
@@ -75,6 +75,7 @@ void	udp_stats(u_long, const char *, int, int);
 void	sctp_protopr(u_long, const char *, int, int);
 void	sctp_stats(u_long, const char *, int, int);
 #endif
+void	arp_stats(u_long, const char *, int, int);
 void	ip_stats(u_long, const char *, int, int);
 void	icmp_stats(u_long, const char *, int, int);
 void	igmp_stats(u_long, const char *, int, int);