/*
* Copyright (c) 2010 Hudson River Trading LLC
* Written by George Neville-Neil gnn@freebsd.org
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Description: The following is a test of the arp entry packet queues
* which replaced the single packet hold entry that existed in the BSDs
* since time immemorial. The test process is:
*
* 1) Find out the current system limit (maxhold)
* 2) Using an IP address for which we do not yet have an entry
* load up an ARP entry packet queue with exactly that many packets.
* 3) Check the arp dropped stat to make sure that we have not dropped
* any packets as yet.
* 4) Add one more packet to the queue.
* 5) Make sure that only one packet was dropped.
*
* CAVEAT: The ARP timer will flush the queue after 1 second so it is
* important not to run this code in a fast loop or the test will
* fail.
*/
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if_arp.h>
#define MSG_SIZE 1024
#define PORT 6969
int
main(int argc, char **argv)
{
int sock;
int maxhold;
size_t size = sizeof(maxhold);
struct sockaddr_in dest;
char message[MSG_SIZE];
struct arpstat arpstat;
size_t len = sizeof(arpstat);
unsigned long dropped = 0;
memset(&message, 1, sizeof(message));
if (sysctlbyname("net.link.ether.inet.maxhold", &maxhold, &size,
NULL, 0) < 0) {
perror("not ok 1 - sysctlbyname failed");
exit(1);
}
#ifdef DEBUG
printf("maxhold is %d\n", maxhold);
#endif /* DEBUG */
if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
perror("not ok 1 - could not open socket");
exit(1);
}
bzero(&dest, sizeof(dest));
if (inet_pton(AF_INET, argv[1], &dest.sin_addr.s_addr) != 1) {
perror("not ok 1 - could not parse address");
exit(1);
}
dest.sin_len = sizeof(dest);
dest.sin_family = AF_INET;
dest.sin_port = htons(PORT);
if (sysctlbyname("net.link.ether.arp.stats", &arpstat, &len,
NULL, 0) < 0) {
perror("not ok 1 - could not get initial arp stats");
exit(1);
}
dropped = arpstat.dropped;
#ifdef DEBUG
printf("dropped before %ld\n", dropped);
#endif /* DEBUG */
/*
* Load up the queue in the ARP entry to the maximum.
* We should not drop any packets at this point.
*/
while (maxhold > 0) {
if (sendto(sock, message, sizeof(message), 0,
(struct sockaddr *)&dest, sizeof(dest)) < 0) {
perror("not ok 1 - could not send packet");
exit(1);
}
maxhold--;
}
if (sysctlbyname("net.link.ether.arp.stats", &arpstat, &len,
NULL, 0) < 0) {
perror("not ok 1 - could not get new arp stats");
exit(1);
}
#ifdef DEBUG
printf("dropped after %ld\n", arpstat.dropped);
#endif /* DEBUG */
if (arpstat.dropped != dropped) {
printf("not ok 1 - Failed, drops changed:"
"before %ld after %ld\n", dropped, arpstat.dropped);
exit(1);
}
dropped = arpstat.dropped;
/* Now add one extra and make sure it is dropped. */
if (sendto(sock, message, sizeof(message), 0,
(struct sockaddr *)&dest, sizeof(dest)) < 0) {
perror("not ok 1 - could not send packet");
exit(1);
}
if (sysctlbyname("net.link.ether.arp.stats", &arpstat, &len,
NULL, 0) < 0) {
perror("not ok 1 - could not get new arp stats");
exit(1);
}
if (arpstat.dropped != (dropped + 1)) {
printf("not ok 1 - Failed to drop one packet: before"
" %ld after %ld\n", dropped, arpstat.dropped);
exit(1);
}
printf("ok\n");
return (0);
}
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