Function set

tools/arp/arp.c:351–459

* Set an individual arp entry */

 * Set an individual arp entry
 */
static int
set(int argc, char **argv)
{
	struct sockaddr_in *addr;
	struct sockaddr_in *dst;	/* what are we looking for */
	struct sockaddr_dl *sdl;
	struct rt_msghdr *rtm;
	struct ether_addr *ea;
	char *host = argv[0], *eaddr = argv[1];
	struct sockaddr_dl sdl_m;

	argc -= 2;
	argv += 2;

	bzero(&sdl_m, sizeof(sdl_m));
	sdl_m.sdl_len = sizeof(sdl_m);
	sdl_m.sdl_family = AF_LINK;

	dst = getaddr(host);
	if (dst == NULL)
		return (1);
	doing_proxy = flags = expire_time = 0;
	while (argc-- > 0) {
		if (strcmp(argv[0], "temp") == 0) {
			struct timespec tp;
			int max_age;
			size_t len = sizeof(max_age);

			clock_gettime(CLOCK_MONOTONIC, &tp);
			if (sysctlbyname("net.link.ether.inet.max_age",
			    &max_age, &len, NULL, 0) != 0)
				xo_err(1, "sysctlbyname");
			expire_time = tp.tv_sec + max_age;
		} else if (strcmp(argv[0], "pub") == 0) {
			flags |= RTF_ANNOUNCE;
			doing_proxy = 1;
			if (argc && strcmp(argv[1], "only") == 0) {
				/*
				 * Compatibility: in pre FreeBSD 8 times
				 * the "only" keyword used to mean that
				 * an ARP entry should be announced, but
				 * not installed into routing table.
				 */
				argc--; argv++;
			}
		} else if (strcmp(argv[0], "blackhole") == 0) {
			if (flags & RTF_REJECT) {
				xo_errx(1, "Choose one of blackhole or reject, "
				    "not both.");
			}
			flags |= RTF_BLACKHOLE;
		} else if (strcmp(argv[0], "reject") == 0) {
			if (flags & RTF_BLACKHOLE) {
				xo_errx(1, "Choose one of blackhole or reject, "
				    "not both.");
			}
			flags |= RTF_REJECT;
		} else {