usr.sbin/traceroute/traceroute.c

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84 /* used to store a bunch of protocol specific values */
94 	struct sockaddr *to;
98 	/* pointers to v4/v6 functions */
108  * Not sufficient to hold the complete packet for ECHO REPLY of a big probe.
110  * Also this buffer needs to be 32 bit aligned. In the future the alignment
111  * requirement will be increased to 64 bit. So, let's use 64 bit alignment now.
115 static struct ip *outip4;	/* output buffer to send as an IPv4 datagram */
116 static struct ip *outip6;	/* output buffer to send as an IPv6 datagram */
118 /* Used to store the ancillary data that comes with the received packets */
132 static struct sockaddr_in whereto;	/* Who to try to reach */
156 ushort_t ident;			/* used to authenticate replies */
161 static int waittime = 5;	/* time to wait for response (in seconds) */
175  * flow and class are specific to IPv6, tos and off are specific to IPv4.
176  * Each protocol uses the ones that are specific to itself, and ignores
325 				    "%s: privilege to specify a loose source "
359 				 * In case it fails, check to see if the problem
474 	 * address to jump back to in traceroute(). Until then, we'll need to
492 		    " directly to a host on an attached network (-r)\n",
525 	 * If it's probe_all, SIGINT makes traceroute skip to probing next IP
536 	 * since family is set to the specific AF found unless it's
537 	 * probe_all. So if family == AF_UNSPEC, we need to init pr4 and pr6.
722 		/* convert it back to a string */
731 		 * packets for that address. Therefore, it's a failure case to
732 		 * ask get_hostinfo() to treat a mapped address as an IPv6
755  * Calculate the packet length to be used, and check against the valid range.
773 		 * IP options field can hold up to 9 gateways. But the API
774 		 * allows you to specify only 8, because the last one is the
810  * don't dictate any, it sets the pick_src to make sure traceroute uses the
894 		 * LBNL bug fixed: used to accept any src address
915 			 * address to whatever the interface has configured on
959 	 * Binding at this point will set the source address to be used
961 	 * IPv6.  If the address being bound to is zero, then the kernel
1073  * Gateway addresses are added to the appropriate passed-in array; the
1164 	 * Set the global variables for each AF. This is going to save us lots
1180 		pr->to = (struct sockaddr *)&whereto;
1196 		pr->to = (struct sockaddr *)&whereto6;
1279 	 * this reason as well as the ability to set the Loose Source and
1288 	 * according to the type of datagram to send.
1352 	 * If a raw IPv4 packet is going to be sent, the Type of Service
1367 	/* We enable or disable to not depend on the kernel default */
1391 	/* Revert to non-privileged user after configuring sockets */
1432 			set_sin((struct sockaddr *)pr4->to, addrp,
1440 			set_sin((struct sockaddr *)pr6->to, addrp,
1488  * Trace the route to the host with given IP address.
1514 	msg6->msg_name = pr->to;
1569 		Fprintf(stderr, "%s to %s", prog, hostname);
1571 		Fprintf(stderr, "%s to %s (%s)", prog, hostname,
1590 		/* interrupt handler sig_handler() jumps back to here */
1655 				send_probe(sndsock, pr->to, outip4, seq, ttl,
1791  * source address kernel is going to pick
1836 		 * If there's no route to the destination, this connect() call
1838 		 * address, so that user can get to see "no route to dest"
1839 		 * message, as it'll try to send the probe packet out and will
1884 	 *  we add sequential 16 bit words to it, and at the end, fold
1897 	/* add back carry outs from top 16 bits to low 16 bits */
1898 	sum = (sum >> 16) + (sum & 0xffff);	/* add hi 16 to low 16 */
1900 	answer = ~sum;				/* truncate to 16 bits */
2021  * Out is assumed to be >= in.
2116  * String to double with optional min and max.
2144  * String to int with optional min and max. Handles decimal and hex.
2185  * where it jumps to.