#ifndef	_RIP_H
#define	_RIP_H

/* Routing Information Protocol (RIP)
 *
 *	This code is derived from the 4.2 BSD version which was
 * used as a spec since no formal specification is known to exist.
 * See RFC 1009, Gateway Requirements, for more details. AGB 4-29-88
 *
 * The draft RIP RFC was used to develop most of this code. The above
 * referred to the basics of the rip_recv() function of RIP.C. The RIP
 * RFC has now been issued as RFC1058. AGB 7-23-88
 *
 * Substantially rewritten and integrated into NOS 9/1989 by KA9Q
 */
#ifndef	_MBUF_H
#include "mbuf.h"
#endif

#ifndef	_IFACE_H
#include "iface.h"
#endif

#ifndef _UDP_H
#include "udp.h"
#endif

#define	RIP_INFINITY	16
#define	RIP_TTL		240	/* Default time-to-live for an entry */
#define	RIPVERSION	1
#define	RIP_IPFAM	2

/* UDP Port for RIP */
#define	RIP_PORT	520

/* RIP Packet Types */
enum ripcmd {
	RIPCMD_REQUEST=1,	/* want info */
	RIPCMD_RESPONSE,	/* responding to request */
	RIPCMD_MAX,
};

#define HOPCNT_INFINITY		16	/* per Xerox NS */
#define MAXRIPROUTES		25	/* maximum # routes per RIP pkt */

struct rip_list {
	struct rip_list *prev;
	struct rip_list *next;	/* doubly linked list */

	/* address to scream at periodically:
	 * this address must have a direct network interface route and an
	 * ARP entry for the appropriate  hardware broadcast address, if approp.
	 */
	int32 dest;

	/* basic rate of RIP clocks on this net interface */
	int32 interval;

	struct timer rip_time;	/* time to output next on this net. iface */

	/* the interface to transmit on  and receive from */
	struct iface *iface;

	/* described below with the mask defs */
	struct {
		unsigned int rip_split:1; /* Do split horizon processing */
		unsigned int rip_us:1;	/* Include ourselves in the list */
	} flags;	
};

/* Host format of a single entry in a RIP response packet */	
struct rip_route {
	uint	addr_fam;
	int32	target;
	int32	metric;
};
#define	RIPROUTE	20	/* Size of each routing entry */
#define	RIPHEADER	4	/* Size of rip header before routes */
#define	MAXRIPPACKET	RIPHEADER + (MAXRIPROUTES*RIPROUTE)

/* RIP statistics counters */
struct rip_stat {
	int32 output;		/* Packets sent */
	int32 rcvd;		/* Packets received */
	int32 request;		/* Number of request packets received */
	int32 response;		/* Number of responses received */
	int32 unknown;		/* Number of unknown command pkts received */
	int32 version;		/* Number of version errors */
	int32 addr_family;	/* Number of address family errors */
	int32 refusals;		/* Number of packets dropped from a host
					on the refuse list */
};

struct rip_refuse {
	struct rip_refuse *prev;
	struct rip_refuse *next;
	int32	target;
};

/* RIP primitives */
int rip_init(void);
void rt_timeout(void *s);
void rip_trigger(void);
int rip_add(int32 dest,int32 interval,int split,int us);
int riprefadd(int32 gateway);
int riprefdrop(int32 gateway);
int ripreq(int32 dest,uint replyport);
int rip_drop(int32 dest);
int nbits(int32 target);
void pullentry(struct rip_route *ep,struct mbuf **bpp);

/* RIP Definition */
extern uint Rip_trace;
extern int Rip_merge;
extern struct rip_stat Rip_stat;
extern struct rip_list *Rip_list;
extern struct rip_refuse *Rip_refuse;
extern struct udp_cb *Rip_cb;

#endif	/* _RIP_H */