xref: /csrg-svn/sys/netinet/ip_icmp.h (revision 4923)
1*4923Swnj /* ip_icmp.h 4.2 81/11/18 */
24807Swnj 
34807Swnj /*
44807Swnj  * Interface Control Message Protocol Definitions.
54807Swnj  * Per RFC 792, September 1981.
64807Swnj  */
74807Swnj 
84807Swnj /*
94807Swnj  * Structure of an icmp header.
104807Swnj  */
114807Swnj struct icmp {
124807Swnj 	u_char	icmp_type;		/* type of message, see below */
134807Swnj 	u_char	icmp_code;		/* type sub code */
144807Swnj 	u_short	icmp_cksum;		/* ones complement cksum of struct */
154807Swnj 	union {
164807Swnj 		u_char ih_pptr;			/* ICMP_PARAMPROB */
17*4923Swnj 		struct in_addr ih_gwaddr;	/* ICMP_REDIRECT */
184807Swnj 		struct ih_idseq {
194807Swnj 			n_short	icd_id;
204807Swnj 			n_short	icd_seq;
214807Swnj 		} ih_idseq;
224807Swnj 	} icmp_hun;
234807Swnj #define	icmp_pptr	icmp_hun.ih_pptr
244807Swnj #define	icmp_gwaddr	icmp_hun.ih_gwaddr
254807Swnj #define	icmp_id		icmp_hun.ih_idseq.icd_id
264807Swnj #define	icmp_seq	icmp_hun.ih_idseq.icd_seq
274807Swnj 	union {
284807Swnj 		struct id_ts {
294807Swnj 			n_time its_otime;
304807Swnj 			n_time its_rtime;
314807Swnj 			n_time its_ttime;
324807Swnj 		} id_ts;
334807Swnj 		struct id_ip  {
344807Swnj 			struct ip idi_ip;
354807Swnj 			/* options and then 64 bits of data */
364807Swnj 		} id_ip;
374807Swnj 	} icmp_dun;
384807Swnj #define	icmp_otime	icmp_dun.id_ts.its_otime
394807Swnj #define	icmp_rtime	icmp_dun.id_ts.its_rtime
404807Swnj #define	icmp_ttime	icmp_dun.id_ts.its_ttime
414807Swnj #define	icmp_ip		icmp_dun.id_ip.idi_ip
424807Swnj };
434807Swnj 
444807Swnj /*
454807Swnj  * Lower bounds on packet lengths for various types.
464807Swnj  * For the error advice packets must first insure that the
474807Swnj  * packet is large enought to contain the returned ip header.
484807Swnj  * Only then can we do the check to see if 64 bits of packet
494807Swnj  * data have been returned, since we need to check the returned
504807Swnj  * ip header length.
514807Swnj  */
524807Swnj #define	ICMP_MINLEN	8				/* abs minimum */
534807Swnj #define	ICMP_TSLEN	(8 + 3 * sizeof (n_time))	/* timestamp */
544807Swnj #define	ICMP_ADVLENMIN	(8 + sizeof (struct ip) + 8)	/* min */
554807Swnj #define	ICMP_ADVLEN(p)	(8 + ((p)->icmp_ip.ip_len << 2) + 8)
564807Swnj 	/* N.B.: must separately check that ip_hl >= 5 */
574807Swnj 
584807Swnj /*
594807Swnj  * Definition of type and code field values.
604807Swnj  */
614807Swnj #define	ICMP_ECHOREPLY		0		/* echo reply */
624807Swnj #define	ICMP_UNREACH		3		/* dest unreachable, codes: */
634807Swnj #define		ICMP_UNREACH_NET	0		/* bad net */
644807Swnj #define		ICMP_UNREACH_HOST	1		/* bad host */
654807Swnj #define		ICMP_UNREACH_PROTOCOL	2		/* bad protocol */
664807Swnj #define		ICMP_UNREACH_PORT	3		/* bad port */
674807Swnj #define		ICMP_UNREACH_NEEDFRAG	4		/* IP_DF caused drop */
684807Swnj #define		ICMP_UNREACH_SRCFAIL	5		/* src route failed */
694807Swnj #define	ICMP_SOURCEQUENCH	4		/* packet lost, slow down */
704807Swnj #define	ICMP_REDIRECT		5		/* shorter route, codes: */
714807Swnj #define		ICMP_REDIRECT_NET	0		/* for network */
724807Swnj #define		ICMP_REDIRECT_HOST	1		/* for host */
734807Swnj #define		ICMP_REDIRECT_TOSNET	2		/* for tos and net */
744807Swnj #define		ICMP_REDIRECT_TOSHOST	3		/* for tos and host */
754807Swnj #define	ICMP_ECHO		8		/* echo service */
764807Swnj #define	ICMP_TIMXCEED		11		/* time exceeded, code: */
774807Swnj #define		ICMP_TIMXCEED_INTRANS	0		/* ttl==0 in transit */
784807Swnj #define		ICMP_TIMXCEED_REASS	1		/* ttl==0 in reass */
794807Swnj #define	ICMP_TSTAMP		13		/* timestamp request */
804807Swnj #define	ICMP_TSTAMPREPLY	14		/* timestamp reply */
814807Swnj #define	ICMP_IREQ		15		/* information request */
824807Swnj #define	ICMP_IREQREPLY		16		/* information reply */
834807Swnj #define	ICMP_PARAMPROB		12		/* ip header bad */
84