traceroute.c

这是一个SIGMA方案的PMP播放器的UCLINUX程序,可播放DVD,VCD,CD MP3...有很好的参考价值.

	"Echo",         "ICMP 9",       "ICMP 10",      "Time Exceeded",
	"Param Problem", "Timestamp",   "Timestamp Reply", "Info Request",
	"Info Reply"
	};

	if(t > 16)
		return("OUT-OF-RANGE");

	return(ttab[t]);
}
#endif

static inline int
packet_ok(u_char *buf, int cc, struct sockaddr_in *from, int seq)
{
	struct icmp *icp;
	u_char type, code;
	int hlen;
	struct ip *ip;

	ip = (struct ip *) buf;
	hlen = ip->ip_hl << 2;
	if (cc < hlen + ICMP_MINLEN) {
#ifdef CONFIG_FEATURE_TRACEROUTE_VERBOSE
		if (verbose)
			printf("packet too short (%d bytes) from %s\n", cc,
				inet_ntoa(from->sin_addr));
#endif
		return (0);
	}
	cc -= hlen;
	icp = (struct icmp *)(buf + hlen);
	type = icp->icmp_type; code = icp->icmp_code;
	if ((type == ICMP_TIMXCEED && code == ICMP_TIMXCEED_INTRANS) ||
	    type == ICMP_UNREACH) {
		struct ip *hip;
		struct udphdr *up;

		hip = &icp->icmp_ip;
		hlen = hip->ip_hl << 2;
		up = (struct udphdr *)((u_char *)hip + hlen);
		if (hlen + 12 <= cc && hip->ip_p == IPPROTO_UDP &&
		    up->source == htons(ident) &&
		    up->dest == htons(port+seq))
			return (type == ICMP_TIMXCEED? -1 : code+1);
	}
#ifdef CONFIG_FEATURE_TRACEROUTE_VERBOSE
	if (verbose) {
		int i;
		u_long *lp = (u_long *)&icp->icmp_ip;

		printf("\n%d bytes from %s to %s: icmp type %d (%s) code %d\n",
			cc, inet_ntoa(from->sin_addr), inet_ntoa(ip->ip_dst),
			type, pr_type(type), icp->icmp_code);
		for (i = 4; i < cc ; i += sizeof(long))
			printf("%2d: x%8.8lx\n", i, *lp++);
	}
#endif
	return(0);
}

static void             /* not inline */
send_probe(int seq, int ttl)
{
	struct opacket *op = outpacket;
	struct ip *ip = &op->ip;
	struct udphdr *up = &op->udp;
	int i;
	struct timezone tz;

	ip->ip_off = 0;
	ip->ip_hl = sizeof(*ip) >> 2;
	ip->ip_p = IPPROTO_UDP;
	ip->ip_len = datalen;
	ip->ip_ttl = ttl;
	ip->ip_v = IPVERSION;
	ip->ip_id = htons(ident+seq);

	up->source = htons(ident);
	up->dest = htons(port+seq);
	up->len = htons((u_short)(datalen - sizeof(struct ip)));
	up->check = 0;

	op->seq = seq;
	op->ttl = ttl;
	(void) gettimeofday(&op->tv, &tz);

	i = sendto(sndsock, (char *)outpacket, datalen, 0, &whereto,
		   sizeof(struct sockaddr));
	if (i < 0 || i != datalen)  {
		if (i<0)
			perror("sendto");
		printf("traceroute: wrote %s %d chars, ret=%d\n", hostname,
			datalen, i);
		(void) fflush(stdout);
	}
}


int
#ifndef CONFIG_TRACEROUTE
main(argc, argv)
#else
traceroute_main(argc, argv)
#endif
	int argc;
	char *argv[];
{
	extern char *optarg;
	extern int optind;
	struct hostent *hp;
	struct sockaddr_in from, *to;
	int ch, i, on, probe, seq, tos, ttl;

	int options = 0;                /* socket options */
	char *source = 0;
	int nprobes = 3;

	on = 1;
	seq = tos = 0;
	to = (struct sockaddr_in *)&whereto;
	while ((ch = getopt(argc, argv, "dm:np:q:rs:t:w:v")) != EOF)
		switch(ch) {
		case 'd':
#ifdef CONFIG_FEATURE_TRACEROUTE_SO_DEBUG
			options |= SO_DEBUG;
#endif
			break;
		case 'm':
			max_ttl = atoi(optarg);
			if (max_ttl <= 1)
				error_msg_and_die("max ttl must be >1.");
			break;
		case 'n':
			nflag++;
			break;
		case 'p':
			port = atoi(optarg);
			if (port < 1)
				error_msg_and_die("port must be >0.");
			break;
		case 'q':
			nprobes = atoi(optarg);
			if (nprobes < 1)
				error_msg_and_die("nprobes must be >0.");
			break;
		case 'r':
			options |= SO_DONTROUTE;
			break;
		case 's':
			/*
			 * set the ip source address of the outbound
			 * probe (e.g., on a multi-homed host).
			 */
			source = optarg;
			break;
		case 't':
			tos = atoi(optarg);
			if (tos < 0 || tos > 255)
				error_msg_and_die("tos must be 0 to 255.");
			break;
		case 'v':
#ifdef CONFIG_FEATURE_TRACEROUTE_VERBOSE
			verbose++;
#endif
			break;
		case 'w':
			waittime = atoi(optarg);
			if (waittime <= 1)
				error_msg_and_die("wait must be >1 sec.");
			break;
		default:
			show_usage();
		}
	argc -= optind;
	argv += optind;

	if (argc < 1)
		show_usage();

	setlinebuf (stdout);

	memset(&whereto, 0, sizeof(struct sockaddr));
	hp = xgethostbyname(*argv);
			to->sin_family = hp->h_addrtype;
	memcpy(&to->sin_addr, hp->h_addr, hp->h_length);
			hostname = (char *)hp->h_name;
	if (*++argv)
		datalen = atoi(*argv);
	if (datalen < 0 || datalen >= MAXPACKET - sizeof(struct opacket))
		error_msg_and_die("packet size must be 0 <= s < %d.",
		    MAXPACKET - sizeof(struct opacket));
	datalen += sizeof(struct opacket);
	outpacket = (struct opacket *)xmalloc((unsigned)datalen);
	memset(outpacket, 0, datalen);
	outpacket->ip.ip_dst = to->sin_addr;
	outpacket->ip.ip_tos = tos;
	outpacket->ip.ip_v = IPVERSION;
	outpacket->ip.ip_id = 0;

	ident = (getpid() & 0xffff) | 0x8000;

	if ((sndsock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) < 0)
		perror_msg_and_die(can_not_create_raw_socket);

	s = create_icmp_socket();

#ifdef CONFIG_FEATURE_TRACEROUTE_SO_DEBUG
	if (options & SO_DEBUG)
		(void) setsockopt(s, SOL_SOCKET, SO_DEBUG,
				  (char *)&on, sizeof(on));
#endif
	if (options & SO_DONTROUTE)
		(void) setsockopt(s, SOL_SOCKET, SO_DONTROUTE,
				  (char *)&on, sizeof(on));
#ifdef SO_SNDBUF
	if (setsockopt(sndsock, SOL_SOCKET, SO_SNDBUF, (char *)&datalen,
		       sizeof(datalen)) < 0)
		perror_msg_and_die("SO_SNDBUF");
#endif
#ifdef IP_HDRINCL
	if (setsockopt(sndsock, IPPROTO_IP, IP_HDRINCL, (char *)&on,
		       sizeof(on)) < 0)
		perror_msg_and_die("IP_HDRINCL");
#endif
#ifdef CONFIG_FEATURE_TRACEROUTE_SO_DEBUG
	if (options & SO_DEBUG)
		(void) setsockopt(sndsock, SOL_SOCKET, SO_DEBUG,
				  (char *)&on, sizeof(on));
#endif
	if (options & SO_DONTROUTE)
		(void) setsockopt(sndsock, SOL_SOCKET, SO_DONTROUTE,
				  (char *)&on, sizeof(on));

	if (source) {
		memset(&from, 0, sizeof(struct sockaddr));
		from.sin_family = AF_INET;
		from.sin_addr.s_addr = inet_addr(source);
		if (from.sin_addr.s_addr == -1)
			error_msg_and_die("unknown host %s", source);
		outpacket->ip.ip_src = from.sin_addr;
#ifndef IP_HDRINCL
		if (bind(sndsock, (struct sockaddr *)&from, sizeof(from)) < 0)
			perror_msg_and_die("bind");
#endif
	}

	fprintf(stderr, "traceroute to %s (%s)", hostname,
		inet_ntoa(to->sin_addr));
	if (source)
		fprintf(stderr, " from %s", source);
	fprintf(stderr, ", %d hops max, %d byte packets\n", max_ttl, datalen);

	for (ttl = 1; ttl <= max_ttl; ++ttl) {
		u_long lastaddr = 0;
		int got_there = 0;
		int unreachable = 0;

		printf("%2d ", ttl);
		for (probe = 0; probe < nprobes; ++probe) {
			int cc, reset_timer;
			struct timeval t1, t2;
			struct timezone tz;
			struct ip *ip;

			(void) gettimeofday(&t1, &tz);
			send_probe(++seq, ttl);
			reset_timer = 1;
			while ((cc = wait_for_reply(s, &from, reset_timer)) != 0) {
				(void) gettimeofday(&t2, &tz);
				if ((i = packet_ok(packet, cc, &from, seq))) {
					reset_timer = 1;
					if (from.sin_addr.s_addr != lastaddr) {
						print(packet, cc, &from);
						lastaddr = from.sin_addr.s_addr;
					}
					printf("  %g ms", deltaT(&t1, &t2));
					switch(i - 1) {
					case ICMP_UNREACH_PORT:
						ip = (struct ip *)packet;
						if (ip->ip_ttl <= 1)
							printf(" !");
						++got_there;
						break;
					case ICMP_UNREACH_NET:
						++unreachable;
						printf(" !N");
						break;
					case ICMP_UNREACH_HOST:
						++unreachable;
						printf(" !H");
						break;
					case ICMP_UNREACH_PROTOCOL:
						++got_there;
						printf(" !P");
						break;
					case ICMP_UNREACH_NEEDFRAG:
						++unreachable;
						printf(" !F");
						break;
					case ICMP_UNREACH_SRCFAIL:
						++unreachable;
						printf(" !S");
						break;
					}
					break;
				} else
					reset_timer = 0;
			}
			if (cc == 0)
				printf(" *");
			(void) fflush(stdout);
		}
		putchar('\n');
		if (got_there || unreachable >= nprobes-1)
			return 0;
	}

	return 0;
}