ping6.c

IPv6环境中的ping实现

			options |= F_FQDN;
			break;
		case 'W':
			options &= ~F_NOUSERDATA;
			options |= F_FQDNOLD;
			break;
#ifdef IPSEC
#ifdef IPSEC_POLICY_IPSEC
		case 'P':
			options |= F_POLICY;
			if (!strncmp("in", optarg, 2)) {
				if ((policy_in = strdup(optarg)) == NULL)
					errx(1, "strdup");
			} else if (!strncmp("out", optarg, 3)) {
				if ((policy_out = strdup(optarg)) == NULL)
					errx(1, "strdup");
			} else
				errx(1, "invalid security policy");
			break;
#else
		case 'A':
			options |= F_AUTHHDR;
			break;
		case 'E':
			options |= F_ENCRYPT;
			break;
#endif /*IPSEC_POLICY_IPSEC*/
#endif /*IPSEC*/
		default:
			usage();
			/*NOTREACHED*/
		}
	}

	argc -= optind;
	argv += optind;

	if (argc < 1) {
		usage();
		/*NOTREACHED*/
	}

	if (argc > 1) {
#ifdef IPV6_RECVRTHDR	/* 2292bis */
		rthlen = CMSG_SPACE(inet6_rth_space(IPV6_RTHDR_TYPE_0,
		    argc - 1));
#else  /* RFC2292 */
		rthlen = inet6_rthdr_space(IPV6_RTHDR_TYPE_0, argc - 1);
#endif
		if (rthlen == 0) {
			errx(1, "too many intermediate hops");
			/*NOTREACHED*/
		}
		ip6optlen += rthlen;
	}

	if (options & F_NIGROUP) {
		target = nigroup(argv[argc - 1]);
		if (target == NULL) {
			usage();
			/*NOTREACHED*/
		}
	} else
		target = argv[argc - 1];

	/* getaddrinfo */
	memset(&hints, 0, sizeof(struct addrinfo));
	hints.ai_flags = AI_CANONNAME;
	hints.ai_family = AF_INET6;
	hints.ai_socktype = SOCK_RAW;
	hints.ai_protocol = IPPROTO_ICMPV6;

	ret_ga = getaddrinfo(target, NULL, &hints, &res);
	if (ret_ga)
		errx(1, "%s", gai_strerror(ret_ga));
	if (res->ai_canonname)
		hostname = res->ai_canonname;
	else
		hostname = target;

	if (!res->ai_addr)
		errx(1, "getaddrinfo failed");

	(void)memcpy(&dst, res->ai_addr, res->ai_addrlen);

	if ((s = socket(res->ai_family, res->ai_socktype,
	    res->ai_protocol)) < 0)
		err(1, "socket");

	/* set the source address if specified. */
	if ((options & F_SRCADDR) &&
	    bind(s, (struct sockaddr *)&src, srclen) != 0) {
		err(1, "bind");
	}

	/* set the gateway (next hop) if specified */
	if (gateway) {
		struct addrinfo ghints, *gres;
		int error;

		memset(&ghints, 0, sizeof(ghints));
		ghints.ai_family = AF_INET6;
		ghints.ai_socktype = SOCK_RAW;
		ghints.ai_protocol = IPPROTO_ICMPV6;

		error = getaddrinfo(gateway, NULL, &hints, &gres);
		if (error) {
			errx(1, "getaddrinfo for the gateway %s: %s",
			     gateway, gai_strerror(error));
		}
		if (gres->ai_next && (options & F_VERBOSE))
			warnx("gateway resolves to multiple addresses");

		if (setsockopt(s, IPPROTO_IPV6, IPV6_NEXTHOP,
			       gres->ai_addr, gres->ai_addrlen)) {
			err(1, "setsockopt(IPV6_NEXTHOP)");
		}

		freeaddrinfo(gres);
	}

	/*
	 * let the kerel pass extension headers of incoming packets,
	 * for privileged socket options
	 */
	if ((options & F_VERBOSE) != 0) {
		int opton = 1;

#ifdef IPV6_RECVHOPOPTS
		if (setsockopt(s, IPPROTO_IPV6, IPV6_RECVHOPOPTS, &opton,
		    sizeof(opton)))
			err(1, "setsockopt(IPV6_RECVHOPOPTS)");
#else  /* old adv. API */
		if (setsockopt(s, IPPROTO_IPV6, IPV6_HOPOPTS, &opton,
		    sizeof(opton)))
			err(1, "setsockopt(IPV6_HOPOPTS)");
#endif
#ifdef IPV6_RECVDSTOPTS
		if (setsockopt(s, IPPROTO_IPV6, IPV6_RECVDSTOPTS, &opton,
		    sizeof(opton)))
			err(1, "setsockopt(IPV6_RECVDSTOPTS)");
#else  /* old adv. API */
		if (setsockopt(s, IPPROTO_IPV6, IPV6_DSTOPTS, &opton,
		    sizeof(opton)))
			err(1, "setsockopt(IPV6_DSTOPTS)");
#endif
#ifdef IPV6_RECVRTHDRDSTOPTS
		if (setsockopt(s, IPPROTO_IPV6, IPV6_RECVRTHDRDSTOPTS, &opton,
		    sizeof(opton)))
			err(1, "setsockopt(IPV6_RECVRTHDRDSTOPTS)");
#endif
	}

	/* revoke root privilege */
	seteuid(getuid());
	setuid(getuid());

	if ((options & F_FLOOD) && (options & F_INTERVAL))
		errx(1, "-f and -i incompatible options");

	if ((options & F_NOUSERDATA) == 0) {
		if (datalen >= sizeof(struct tv32)) {
			/* we can time transfer */
			timing = 1;
		} else
			timing = 0;
		/* in F_VERBOSE case, we may get non-echoreply packets*/
		if (options & F_VERBOSE)
			packlen = 2048 + IP6LEN + ICMP6ECHOLEN + EXTRA;
		else
			packlen = datalen + IP6LEN + ICMP6ECHOLEN + EXTRA;
	} else {
		/* suppress timing for node information query */
		timing = 0;
		datalen = 2048;
		packlen = 2048 + IP6LEN + ICMP6ECHOLEN + EXTRA;
	}

	if (!(packet = (u_char *)malloc((u_int)packlen)))
		err(1, "Unable to allocate packet");
	if (!(options & F_PINGFILLED))
		for (i = ICMP6ECHOLEN; i < packlen; ++i)
			*datap++ = i;

	ident = getpid() & 0xFFFF;
#ifndef __OpenBSD__
	gettimeofday(&timeout, NULL);
	srand((unsigned int)(timeout.tv_sec ^ timeout.tv_usec ^ (long)ident));
	memset(nonce, 0, sizeof(nonce));
	for (i = 0; i < sizeof(nonce); i += sizeof(int))
		*((int *)&nonce[i]) = rand();
#else
	memset(nonce, 0, sizeof(nonce));
	for (i = 0; i < sizeof(nonce); i += sizeof(u_int32_t))
		*((u_int32_t *)&nonce[i]) = arc4random();
#endif

	hold = 1;

	if (options & F_SO_DEBUG)
		(void)setsockopt(s, SOL_SOCKET, SO_DEBUG, (char *)&hold,
		    sizeof(hold));
	optval = IPV6_DEFHLIM;
	if (IN6_IS_ADDR_MULTICAST(&dst.sin6_addr))
		if (setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
		    &optval, sizeof(optval)) == -1)
			err(1, "IPV6_MULTICAST_HOPS");
#ifdef IPV6_USE_MIN_MTU
	if (mflag != 1) {
		optval = mflag > 1 ? 0 : 1;

		if (setsockopt(s, IPPROTO_IPV6, IPV6_USE_MIN_MTU,
		    &optval, sizeof(optval)) == -1)
			err(1, "setsockopt(IPV6_USE_MIN_MTU)");
	}
#ifdef IPV6_RECVPATHMTU
	else {
		optval = 1;
		if (setsockopt(s, IPPROTO_IPV6, IPV6_RECVPATHMTU,
		    &optval, sizeof(optval)) == -1)
			err(1, "setsockopt(IPV6_RECVPATHMTU)");
	}
#endif /* IPV6_RECVPATHMTU */
#endif /* IPV6_USE_MIN_MTU */

#ifdef IPSEC
#ifdef IPSEC_POLICY_IPSEC
	if (options & F_POLICY) {
		if (setpolicy(s, policy_in) < 0)
			errx(1, "%s", ipsec_strerror());
		if (setpolicy(s, policy_out) < 0)
			errx(1, "%s", ipsec_strerror());
	}
#else
	if (options & F_AUTHHDR) {
		optval = IPSEC_LEVEL_REQUIRE;
#ifdef IPV6_AUTH_TRANS_LEVEL
		if (setsockopt(s, IPPROTO_IPV6, IPV6_AUTH_TRANS_LEVEL,
		    &optval, sizeof(optval)) == -1)
			err(1, "setsockopt(IPV6_AUTH_TRANS_LEVEL)");
#else /* old def */
		if (setsockopt(s, IPPROTO_IPV6, IPV6_AUTH_LEVEL,
		    &optval, sizeof(optval)) == -1)
			err(1, "setsockopt(IPV6_AUTH_LEVEL)");
#endif
	}
	if (options & F_ENCRYPT) {
		optval = IPSEC_LEVEL_REQUIRE;
		if (setsockopt(s, IPPROTO_IPV6, IPV6_ESP_TRANS_LEVEL,
		    &optval, sizeof(optval)) == -1)
			err(1, "setsockopt(IPV6_ESP_TRANS_LEVEL)");
	}
#endif /*IPSEC_POLICY_IPSEC*/
#endif

#ifdef ICMP6_FILTER
    {
	struct icmp6_filter filt;
	if (!(options & F_VERBOSE)) {
		ICMP6_FILTER_SETBLOCKALL(&filt);
		if ((options & F_FQDN) || (options & F_FQDNOLD) ||
		    (options & F_NODEADDR) || (options & F_SUPTYPES))
			ICMP6_FILTER_SETPASS(ICMP6_NI_REPLY, &filt);
		else
			ICMP6_FILTER_SETPASS(ICMP6_ECHO_REPLY, &filt);
	} else {
		ICMP6_FILTER_SETPASSALL(&filt);
	}
	if (setsockopt(s, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
	    sizeof(filt)) < 0)
		err(1, "setsockopt(ICMP6_FILTER)");
    }
#endif /*ICMP6_FILTER*/

	/* let the kerel pass extension headers of incoming packets */
	if ((options & F_VERBOSE) != 0) {
		int opton = 1;

#ifdef IPV6_RECVRTHDR
		if (setsockopt(s, IPPROTO_IPV6, IPV6_RECVRTHDR, &opton,
		    sizeof(opton)))
			err(1, "setsockopt(IPV6_RECVRTHDR)");
#else  /* old adv. API */
		if (setsockopt(s, IPPROTO_IPV6, IPV6_RTHDR, &opton,
		    sizeof(opton)))
			err(1, "setsockopt(IPV6_RTHDR)");
#endif
	}

/*
	optval = 1;
	if (IN6_IS_ADDR_MULTICAST(&dst.sin6_addr))
		if (setsockopt(s, IPPROTO_IPV6, IPV6_MULTICAST_LOOP,
		    &optval, sizeof(optval)) == -1)
			err(1, "IPV6_MULTICAST_LOOP");
*/

	/* Specify the outgoing interface and/or the source address */
	if (usepktinfo)
		ip6optlen += CMSG_SPACE(sizeof(struct in6_pktinfo));

	if (hoplimit != -1)
		ip6optlen += CMSG_SPACE(sizeof(int));

#ifdef IPV6_REACHCONF
	if (options & F_REACHCONF)
		ip6optlen += CMSG_SPACE(0);
#endif

	/* set IP6 packet options */
	if (ip6optlen) {
		if ((scmsg = (char *)malloc(ip6optlen)) == 0)
			errx(1, "can't allocate enough memory");
		smsghdr.msg_control = (caddr_t)scmsg;
		smsghdr.msg_controllen = ip6optlen;
		scmsgp = (struct cmsghdr *)scmsg;
	}
	if (usepktinfo) {
		pktinfo = (struct in6_pktinfo *)(CMSG_DATA(scmsgp));
		memset(pktinfo, 0, sizeof(*pktinfo));
		scmsgp->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
		scmsgp->cmsg_level = IPPROTO_IPV6;
		scmsgp->cmsg_type = IPV6_PKTINFO;
		scmsgp = CMSG_NXTHDR(&smsghdr, scmsgp);
	}

	/* set the outgoing interface */
	if (ifname) {
#ifndef USE_SIN6_SCOPE_ID
		/* pktinfo must have already been allocated */
		if ((pktinfo->ipi6_ifindex = if_nametoindex(ifname)) == 0)
			errx(1, "%s: invalid interface name", ifname);
#else
		if ((dst.sin6_scope_id = if_nametoindex(ifname)) == 0)
			errx(1, "%s: invalid interface name", ifname);
#endif
	}
	if (hoplimit != -1) {
		scmsgp->cmsg_len = CMSG_LEN(sizeof(int));
		scmsgp->cmsg_level = IPPROTO_IPV6;
		scmsgp->cmsg_type = IPV6_HOPLIMIT;
		*(int *)(CMSG_DATA(scmsgp)) = hoplimit;

		scmsgp = CMSG_NXTHDR(&smsghdr, scmsgp);
	}
#ifdef IPV6_REACHCONF
	if (options & F_REACHCONF) {
		scmsgp->cmsg_len = CMSG_LEN(0);
		scmsgp->cmsg_level = IPPROTO_IPV6;
		scmsgp->cmsg_type = IPV6_REACHCONF;

		scmsgp = CMSG_NXTHDR(&smsghdr, scmsgp);
	}
#endif

	if (argc > 1) {	/* some intermediate addrs are specified */
		int hops, error;
#ifdef USE_RFC2292BIS
		int rthdrlen;
#endif

#ifdef USE_RFC2292BIS
		rthdrlen = inet6_rth_space(IPV6_RTHDR_TYPE_0, argc - 1);
		scmsgp->cmsg_len = CMSG_LEN(rthdrlen);
		scmsgp->cmsg_level = IPPROTO_IPV6;
		scmsgp->cmsg_type = IPV6_RTHDR;
		rthdr = (struct ip6_rthdr *)CMSG_DATA(scmsgp);
		rthdr = inet6_rth_init((void *)rthdr, rthdrlen,
		    IPV6_RTHDR_TYPE_0, argc - 1);
		if (rthdr == NULL)
			errx(1, "can't initialize rthdr");
#else  /* old advanced API */
		if ((scmsgp = (struct cmsghdr *)inet6_rthdr_init(scmsgp,
		    IPV6_RTHDR_TYPE_0)) == 0)
			errx(1, "can't initialize rthdr");
#endif /* USE_RFC2292BIS */

		for (hops = 0; hops < argc - 1; hops++) {
			struct addrinfo *iaip;

			if ((error = getaddrinfo(argv[hops], NULL, &hints,
			    &iaip)))
				errx(1, "%s", gai_strerror(error));
			if (SIN6(iaip->ai_addr)->sin6_family != AF_INET6)
				errx(1,
				    "bad addr family of an intermediate addr");

#ifdef USE_RFC2292BIS
			if (inet6_rth_add(rthdr,
			    &(SIN6(iaip->ai_addr))->sin6_addr))
				errx(1, "can't add an intermediate node");
#else  /* old advanced API */
			if (inet6_rthdr_add(scmsgp,
			    &(SIN6(iaip->ai_addr))->sin6_addr,
			    IPV6_RTHDR_LOOSE))
				errx(1, "can't add an intermediate node");
#endif /* USE_RFC2292BIS */
			freeaddrinfo(iaip);
		}

#ifndef USE_RFC2292BIS
		if (inet6_rthdr_lasthop(scmsgp, IPV6_RTHDR_LOOSE))
			errx(1, "can't set the last flag");
#endif

		scmsgp = CMSG_NXTHDR(&smsghdr, scmsgp);
	}

	if (!(options & F_SRCADDR)) {
		/*
		 * get the source address. XXX since we revoked the root
		 * privilege, we cannot use a raw socket for this.
		 */
		int dummy, len = sizeof(src);

		if ((dummy = socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
			err(1, "UDP socket");

		src.sin6_family = AF_INET6;
		src.sin6_addr = dst.sin6_addr;
		src.sin6_port = ntohs(DUMMY_PORT);
		src.sin6_scope_id = dst.sin6_scope_id;

#ifdef USE_RFC2292BIS
		if (pktinfo &&
		    setsockopt(dummy, IPPROTO_IPV6, IPV6_PKTINFO,
		    (void *)pktinfo, sizeof(*pktinfo)))
			err(1, "UDP setsockopt(IPV6_PKTINFO)");

		if (hoplimit != -1 &&
		    setsockopt(dummy, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
		    (void *)&hoplimit, sizeof(hoplimit)))
			err(1, "UDP setsockopt(IPV6_UNICAST_HOPS)");

		if (hoplimit != -1 &&
		    setsockopt(dummy, IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
		    (void *)&hoplimit, sizeof(hoplimit)))
			err(1, "UDP setsockopt(IPV6_MULTICAST_HOPS)");

		if (rthdr &&
		    setsockopt(dummy, IPPROTO_IPV6, IPV6_RTHDR,
		    (void *)rthdr, (rthdr->ip6r_len + 1) << 3))
			err(1, "UDP setsockopt(IPV6_RTHDR)");
#else  /* old advanced API */
		if (smsghdr.msg_control &&
		    setsockopt(dummy, IPPROTO_IPV6, IPV6_PKTOPTIONS,
		    (void *)smsghdr.msg_control, smsghdr.msg_controllen))
			err(1, "UDP setsockopt(IPV6_PKTOPTIONS)");
#endif

		if (connect(dummy, (struct sockaddr *)&src, len) < 0)
			err(1, "UDP connect");

		if (getsockname(dummy, (struct sockaddr *)&src, &len) < 0)
			err(1, "getsockname");

		close(dummy);
	}

#if defined(SO_SNDBUF) && defined(SO_RCVBUF)
	if (sockbufsize) {
		if (datalen > sockbufsize)
			warnx("you need -b to increase socket buffer size");
		if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &sockbufsize,
		    sizeof(sockbufsize)) < 0)
			err(1, "setsockopt(SO_SNDBUF)");
		if (setsockopt(s, SOL_SOCKET, SO_RCVBUF, &sockbufsize,
		    sizeof(sockbufsize)) < 0)
			err(1, "setsockopt(SO_RCVBUF)");
	}
	else {
		if (datalen > 8 * 1024)	/*XXX*/
			warnx("you need -b to increase socket buffer size");
		/*
		 * When pinging the broadcast address, you can get a lot of
		 * answers. Doing something so evil is useful if you are trying
		 * to stress the ethernet, or just want to fill the arp cache
		 * to get some stuff for /etc/ethers.
		 */
		hold = 48 * 1024;
		setsockopt(s, SOL_SOCKET, SO_RCVBUF, (char *)&hold,
		    sizeof(hold));
	}
#endif

	optval = 1;
#ifndef USE_SIN6_SCOPE_ID
#ifdef IPV6_RECVPKTINFO
	if (setsockopt(s, IPPROTO_IPV6, IPV6_RECVPKTINFO, &optval,
	    sizeof(optval)) < 0)
		warn("setsockopt(IPV6_RECVPKTINFO)"); /* XXX err? */
#else  /* old adv. API */
	if (setsockopt(s, IPPROTO_IPV6, IPV6_PKTINFO, &optval,
	    sizeof(optval)) < 0)
		warn("setsockopt(IPV6_PKTINFO)"); /* XXX err? */
#endif
#endif /* USE_SIN6_SCOPE_ID */
#ifdef IPV6_RECVHOPLIMIT
	if (setsockopt(s, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &optval,
	    sizeof(optval)) < 0)
		warn("setsockopt(IPV6_RECVHOPLIMIT)"); /* XXX err? */
#else  /* old adv. API */
	if (setsockopt(s, IPPROTO_IPV6, IPV6_HOPLIMIT, &optval,
	    sizeof(optval)) < 0)
		warn("setsockopt(IPV6_HOPLIMIT)"); /* XXX err? */
#endif

	printf("PING6(%lu=40+8+%lu bytes) ", (unsigned long)(40 + pingerlen()),
	    (unsigned long)(pingerlen() - 8));
	printf("%s --> ", pr_addr((struct sockaddr *)&src, sizeof(src)));
	printf("%s\n", pr_addr((struct sockaddr *)&dst, sizeof(dst)));

	while (preload--)		/* Fire off them quickies. */
		(void)pinger();

	(void)signal(SIGINT, onsignal);
#ifdef SIGINFO
	(void)signal(SIGINFO, onsignal);
#endif

	if ((options & F_FLOOD) == 0) {
		(void)signal(SIGALRM, onsignal);
		itimer.it_interval = interval;
		itimer.it_value = interval;
		(void)setitimer(ITIMER_REAL, &itimer, NULL);
		if (ntransmitted)
			retransmit();
	}