Category : Network Files
Archive   : KA9Q.ZIP
Filename : NETROM.H

/* net/rom support definitions
* Copyright 1989 by Daniel M. Frank, W9NK. Permission granted for
* non-commercial distribution only.
*/

#define NR3HLEN 15 /* length of a net/rom level 3 hdr, */
#define NR3DLEN 241 /* max data size in net/rom l3 packet */
#define NR3NODESIG 0xff /* signature for nodes broadcast */
#define NR3NODEHL 7 /* nodes bc header length */

#define NRNUMIFACE 10 /* number of interfaces associated */
/* with net/rom network layer */
#define NRNUMCHAINS 17 /* number of chains in the */
/* neighbor and route hash tables */
#define NRRTDESTLEN 21 /* length of destination entry in */
/* nodes broadcast */
#define NRDESTPERPACK 11 /* maximum number of destinations per */
/* nodes packet */

/* Internal representation of net/rom network layer header */
struct nr3hdr {
struct ax25_addr source ; /* callsign of origin node */
struct ax25_addr dest ; /* callsign of destination node */
unsigned ttl ; /* time-to-live */
} ;

/* Internal representation of net/rom routing broadcast destination */
/* entry */
struct nr3dest {
struct ax25_addr dest ; /* destination callsign */
char alias[7] ; /* ident, upper case ASCII, blank-filled */
struct ax25_addr neighbor ; /* best-quality neighbor */
unsigned quality ; /* quality of route for this neighbor */
} ;


/* net/rom interface table entry */
struct nriface {
struct interface *interface ; /* pointer to ax.25 interface */
char alias[7] ; /* alias for this interface's node */
/* broadcasts */
unsigned quality ; /* net/rom link quality estimate */
} ;

/* net/rom neighbor table structure */
struct nrnbr_tab {
struct nrnbr_tab *next ; /* doubly linked list pointers */
struct nrnbr_tab *prev ;
char call[AXALEN*3] ; /* call of neighbor + 2 digis max */
unsigned interface ; /* offset of neighbor's port in */
/* interface table */
unsigned refcnt ; /* how many routes for this neighbor? */
} ;

#define NULLNTAB (struct nrnbr_tab *)0


/* A list of these structures is provided for each route table */
/* entry. They bind a destination to a neighbor node. If the */
/* list of bindings becomes empty, the route table entry is */
/* automatically deleted. */

struct nr_bind {
struct nr_bind *next ; /* doubly linked list */
struct nr_bind *prev ;
unsigned quality ; /* quality estimate */
unsigned obsocnt ; /* obsolescence count */
unsigned flags ;
#define NRB_PERMANENT 0x01 /* entry never times out */
#define NRB_RECORDED 0x02 /* a "record route" entry */
struct nrnbr_tab *via ; /* route goes via this neighbor */
} ;

#define NULLNRBIND (struct nr_bind *)0


/* net/rom routing table entry */

struct nrroute_tab {
struct nrroute_tab *next ; /* doubly linked list pointers */
struct nrroute_tab *prev ;
char alias[7] ; /* alias of node */
struct ax25_addr call ; /* callsign of node */
unsigned num_routes ; /* how many routes in bindings list? */
struct nr_bind *routes ; /* list of neighbors */

} ;

#define NULLNRRTAB (struct nrroute_tab *)0


/* The net/rom nodes broadcast filter structure */
struct nrnf_tab {
struct nrnf_tab *next ; /* doubly linked list */
struct nrnf_tab *prev ;
struct ax25_addr neighbor ; /* call of neighbor to filter */
unsigned interface ; /* filter on this interface */
} ;

#define NULLNRNFTAB (struct nrnf_tab *)0


/* The interface table */
extern struct nriface nrifaces[NRNUMIFACE] ;

/* How many interfaces are in use */
extern unsigned nr_numiface ;

/* The neighbor hash table (hashed on neighbor callsign) */
extern struct nrnbr_tab *nrnbr_tab[NRNUMCHAINS] ;

/* The routes hash table (hashed on destination callsign) */
extern struct nrroute_tab *nrroute_tab[NRNUMCHAINS] ;

/* The nodes broadcast filter table */
extern struct nrnf_tab *nrnf_tab[NRNUMCHAINS] ;

/* filter modes: */
#define NRNF_NOFILTER 0 /* don't filter */
#define NRNF_ACCEPT 1 /* accept broadcasts from stations in list */
#define NRNF_REJECT 2 /* reject broadcasts from stations in list */

/* The filter mode */
extern unsigned nr_nfmode ;

/* The time-to-live for net/rom network layer packets */
extern unsigned nr_ttl ;

/* The obsolescence count initializer */
extern unsigned obso_init ;

/* The threshhold at which routes becoming obsolete are not broadcast */
extern unsigned obso_minbc ;

/* The quality threshhold below which routes in a broadcast will */
/* be ignored */
extern unsigned nr_autofloor ;

/* The maximum number of routes maintained for a destination. */
/* If the list fills up, only the highest quality routes are */
/* kept. This limiting is done to avoid possible over-use of */
/* memory for routing tables in closely spaced net/rom networks. */
extern unsigned nr_maxroutes ;

/* Whether we want to broadcast the contents of our routing
* table, or just our own callsign and alias:
*/
extern unsigned nr_verbose ;

/* The netrom pseudo-interface */
extern struct interface *nr_interface ;

/* Functions */
#if (UNIX || ATARI_ST)
extern struct nrroute_tab *find_nrroute() ;
extern struct ax25_addr *find_nralias() ;
extern struct nrnbr_tab *find_nrnbr() ;
extern struct nrnf_tab *find_nrnf() ;
extern int nr_routeadd() ;
extern int nr_routedrop() ;
extern int nr_nfadd() ;
extern int nr_nfdrop() ;
extern char *nr_getroute() ;
extern int ntohnr3() ;
extern struct mbuf *htonnr3() ;
extern int ntohnrdest() ;
extern struct mbuf *htonnrdest() ;
#else
extern struct nrroute_tab *find_nrroute(struct ax25_addr *) ;
extern struct ax25_addr *find_nralias(char *) ;
extern struct nrnbr_tab *find_nrnbr(struct ax25_addr *, unsigned) ;
extern struct nrnf_tab *find_nrnf(struct ax25_addr *, unsigned) ;
extern int nr_routeadd(char *, struct ax25_addr *, unsigned,
unsigned, char *, unsigned, unsigned) ;
extern int nr_routedrop(struct ax25_addr *, struct ax25_addr *, unsigned) ;
extern int nr_nfadd(struct ax25_addr *, unsigned) ;
extern int nr_nfdrop(struct ax25_addr *, unsigned) ;
extern char *nr_getroute(struct ax25_addr *) ;
extern int ntohnr3(struct nr3hdr *,struct mbuf **) ;
extern struct mbuf *htonnr3(struct nr3hdr *) ;
extern int ntohnrdest(struct nr3dest *,struct mbuf **) ;
extern struct mbuf *htonnrdest(struct nr3dest *) ;
#endif