bird/nest/route.h
Martin Mares 7de45ba4a0 Kernel route syncer supports multiple tables.
The changes are just too extensive for lazy me to list them
there, but see the comment at the top of sysdep/unix/krt.c.
The code got a bit more ifdeffy than I'd like, though.

Also fixed a bunch of FIXME's and added a couple of others. :)
1999-08-03 19:33:22 +00:00

322 lines
11 KiB
C

/*
* BIRD Internet Routing Daemon -- Routing Table
*
* (c) 1998--1999 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_ROUTE_H_
#define _BIRD_ROUTE_H_
#include "lib/lists.h"
#include "lib/resource.h"
#include "lib/timer.h"
struct protocol;
struct proto;
/*
* Generic data structure for storing network prefixes. Also used
* for the master routing table. Currently implemented as a hash
* table.
*
* Available operations:
* - insertion of new entry
* - deletion of entry
* - searching for entry by network prefix
* - asynchronous retrieval of fib contents
*/
struct fib_node {
struct fib_node *next; /* Next in hash chain */
struct fib_iterator *readers; /* List of readers of this node */
byte pxlen;
byte flags; /* User-defined */
byte x0, x1; /* User-defined */
ip_addr prefix; /* In host order */
};
struct fib_iterator { /* See lib/slists.h for an explanation */
struct fib_iterator *prev, *next; /* Must be synced with struct fib_node! */
struct fib_node *node; /* Or NULL if freshly merged */
byte efef; /* 0xff to distinguish between iterator and node */
byte pad[3];
unsigned int hash;
};
struct fib {
pool *fib_pool; /* Pool holding all our data */
slab *fib_slab; /* Slab holding all fib nodes */
struct fib_node **hash_table; /* Node hash table */
unsigned int hash_size; /* Number of hash table entries (a power of two) */
unsigned int hash_order; /* Binary logarithm of hash_size */
unsigned int hash_shift; /* 16 - hash_log */
unsigned int entries; /* Number of entries */
unsigned int entries_min, entries_max;/* Entry count limits (else start rehashing) */
void (*init)(struct fib_node *); /* Constructor */
};
void fib_init(struct fib *, pool *, unsigned node_size, unsigned hash_order, void (*init)(struct fib_node *));
void *fib_find(struct fib *, ip_addr *, int); /* Find or return NULL if doesn't exist */
void *fib_get(struct fib *, ip_addr *, int); /* Find or create new if nonexistent */
void fib_delete(struct fib *, void *); /* Remove fib entry */
void fib_free(struct fib *); /* Destroy the fib */
void fib_check(struct fib *); /* Consistency check for debugging */
void fit_init(struct fib_iterator *, struct fib *); /* Internal functions, don't call */
struct fib_node *fit_get(struct fib *, struct fib_iterator *);
void fit_put(struct fib_iterator *, struct fib_node *);
#define FIB_WALK(fib, z) do { \
struct fib_node *z, **ff = (fib)->hash_table; \
unsigned int count = (fib)->hash_size; \
while (count--) \
for(z = *ff++; z; z=z->next)
#define FIB_WALK_END } while (0)
#define FIB_ITERATE_INIT(it, fib) fit_init(it, fib)
#define FIB_ITERATE_START(fib, it, z) do { \
struct fib_node *z = fit_get(fib, it); \
unsigned int count = (fib)->hash_size; \
unsigned int hpos = (it)->hash; \
for(;;) { \
fis_again: if (!z) { \
if (++hpos >= count) \
break; \
z = (fib)->hash_table[hpos]; \
goto fis_again; \
}
#define FIB_ITERATE_END(z) z = z->next; } } while(0)
#define FIB_ITERATE_PUT(it, z) fit_put(it, z)
/*
* Master Routing Tables. Generally speaking, each of them contains a FIB
* with each entry pointing to a list of route entries representing routes
* to given network (with the selected one at the head).
*
* Each of the RTE's contains variable data (the preference and protocol-dependent
* metrics) and a pointer to a route attribute block common for many routes).
*
* It's guaranteed that there is at most one RTE for every (prefix,proto) pair.
*/
struct rtable_config {
node n;
char *name;
struct rtable *table;
struct proto_config *krt_attached; /* Kernel syncer attached to this table */
};
typedef struct rtable {
node n; /* Node in list of all tables */
struct fib fib;
char *name; /* Name of this table */
list hooks; /* List of announcement hooks */
} rtable;
typedef struct network {
struct fib_node n; /* FIB flags reserved for kernel syncer */
struct rte *routes; /* Available routes for this network */
} net;
typedef struct rte {
struct rte *next;
net *net; /* Network this RTE belongs to */
struct rta *attrs; /* Attributes of this route */
byte flags; /* Flags (REF_...) */
byte pflags; /* Protocol-specific flags */
word pref; /* Route preference */
bird_clock_t lastmod; /* Last modified */
union { /* Protocol-dependent data (metrics etc.) */
#ifdef CONFIG_RIP
struct {
node garbage; /* List for garbage collection */
byte metric; /* RIP metric */
u16 tag; /* External route tag */
} rip;
#endif
#ifdef CONFIG_OSPF
struct {
u32 metric1, metric2; /* OSPF Type 1 and Type 2 metrics */
u32 tag; /* External route tag */
} ospf;
#endif
#ifdef CONFIG_BGP
struct {
} bgp;
#endif
struct { /* Routes generated by krt sync (both temporary and inherited ones) */
s8 src; /* Alleged route source (see krt.h) */
u8 proto; /* Kernel source protocol ID */
u8 type; /* Kernel route type */
u8 seen; /* Seen during last scan */
u32 metric; /* Kernel metric */
} krt;
} u;
} rte;
#define REF_COW 1 /* Copy this rte on write */
struct config;
void rt_init(void);
void rt_preconfig(struct config *);
void rt_commit(struct config *);
void rt_setup(pool *, rtable *, char *);
static inline net *net_find(rtable *tab, ip_addr addr, unsigned len) { return (net *) fib_find(&tab->fib, &addr, len); }
static inline net *net_get(rtable *tab, ip_addr addr, unsigned len) { return (net *) fib_get(&tab->fib, &addr, len); }
rte *rte_find(net *net, struct proto *p);
rte *rte_get_temp(struct rta *);
void rte_update(rtable *tab, net *net, struct proto *p, rte *new);
void rte_discard(rtable *tab, rte *old);
void rte_dump(rte *);
void rte_free(rte *);
rte *rte_do_cow(rte *);
static inline rte * rte_cow(rte *r) { return (r->flags & REF_COW) ? rte_do_cow(r) : r; }
void rt_dump(rtable *);
void rt_dump_all(void);
void rt_feed_baby(struct proto *p);
void rt_prune(rtable *tab);
void rt_prune_all(void);
/*
* Route Attributes
*
* Beware: All standard BGP attributes must be represented here instead
* of making them local to the route. This is needed to ensure proper
* construction of BGP route attribute lists.
*/
typedef struct rta {
struct rta *next, *prev; /* Hash chain */
struct rta *garbage; /* Garbage collector chain */
struct proto *proto; /* Protocol instance */
unsigned uc; /* Use count */
byte source; /* Route source (RTS_...) */
byte scope; /* Route scope (SCOPE_... -- see ip.h) */
byte cast; /* Casting type (RTC_...) */
byte dest; /* Route destination type (RTD_...) */
byte flags; /* Route flags (RTF_...) */
byte aflags; /* Attribute cache flags (RTAF_...) */
byte rfu, rfu2; /* Padding */
ip_addr gw; /* Next hop */
ip_addr from; /* Advertising router */
struct iface *iface; /* Outgoing interface */
struct ea_list *attrs; /* Extended Attribute chain */
} rta;
#define RTS_DUMMY 0 /* Dummy route to be removed soon */
#define RTS_STATIC 1 /* Normal static route */
#define RTS_INHERIT 2 /* Route inherited from kernel */
#define RTS_DEVICE 3 /* Device route */
#define RTS_STATIC_DEVICE 4 /* Static device route */
#define RTS_REDIRECT 5 /* Learned via redirect */
#define RTS_RIP 6 /* RIP route */
#define RTS_RIP_EXT 7 /* RIP external route */
#define RTS_OSPF 8 /* OSPF route */
#define RTS_OSPF_EXT 9 /* OSPF external route */
#define RTS_OSPF_IA 10 /* OSPF inter-area route */
#define RTS_OSPF_BOUNDARY 11 /* OSPF route to boundary router (???) */
#define RTS_BGP 12 /* BGP route */
#define RTC_UNICAST 0
#define RTC_BROADCAST 1
#define RTC_MULTICAST 2
#define RTC_ANYCAST 3 /* IPv6 Anycast */
#define RTD_ROUTER 0 /* Next hop is neighbor router */
#define RTD_DEVICE 1 /* Points to device */
#define RTD_BLACKHOLE 2 /* Silently drop packets */
#define RTD_UNREACHABLE 3 /* Reject as unreachable */
#define RTD_PROHIBIT 4 /* Administratively prohibited */
#define RTF_EXTERIOR 1 /* Learned via exterior protocol */
#define RTF_TAGGED 2 /* Tagged external route learned via IGP */
#define RTAF_CACHED 1 /* This is a cached rta */
/*
* Extended Route Attributes
*/
typedef struct eattr {
word id; /* EA_CODE(EAP_..., protocol-dependent ID) */
byte flags; /* Protocol-dependent flags */
byte type; /* Attribute type and several flags (EAF_...) */
union {
u32 data;
struct adata *ptr; /* Attribute data elsewhere */
} u;
} eattr;
/* FIXME: Introduce real protocol numbers? */
#define EAP_GENERIC 0 /* Generic attributes */
#define EAP_BGP 1 /* BGP attributes */
#define EAP_RIP 2 /* RIP */
#define EA_CODE(proto,id) (((proto) << 8) | (id))
#define EA_PROTO(ea) ((ea) >> 8)
#define EA_ID(ea) ((ea) & 0xff)
#define EAF_TYPE_MASK 0x0f /* Mask with this to get type */
#define EAF_TYPE_INT 0x01 /* 32-bit signed integer number */
#define EAF_TYPE_OPAQUE 0x02 /* Opaque byte string (not filterable) */
#define EAF_TYPE_IP_ADDRESS 0x04 /* IP address [FIXME: embed at least for IPv4?] */
#define EAF_TYPE_AS_PATH 0x06 /* BGP AS path [FIXME: define storage layout] */
#define EAF_TYPE_INT_SET 0x0a /* Set of integers (e.g., a community list) */
#define EAF_EMBEDDED 0x01 /* Data stored in eattr.u.data (part of type spec) */
#define EAF_VAR_LENGTH 0x02 /* Attribute length is variable */
#define EAF_INLINE 0x80 /* Copy of an attribute inlined in rte (temporary ea_lists only) */
struct adata {
unsigned int length;
byte data[0];
};
typedef struct ea_list {
struct ea_list *next; /* In case we have an override list */
byte flags; /* Flags: EALF_... */
byte rfu;
word count; /* Number of attributes */
eattr attrs[0]; /* Attribute definitions themselves */
} ea_list;
#define EALF_SORTED 1 /* Attributes are sorted by code */
#define EALF_BISECT 2 /* Use interval bisection for searching */
#define EALF_CACHED 4 /* Attributes belonging to cached rta */
eattr *ea_find(ea_list *, unsigned ea);
void ea_dump(ea_list *);
void ea_sort(ea_list *); /* Sort entries in all sub-lists */
unsigned ea_scan(ea_list *); /* How many bytes do we need for merged ea_list (0=merge not needed) */
void ea_merge(ea_list *from, ea_list *to); /* Merge sub-lists to allocated buffer */
void rta_init(void);
rta *rta_lookup(rta *); /* Get rta equivalent to this one, uc++ */
static inline rta *rta_clone(rta *r) { r->uc++; return r; }
void rta__free(rta *r);
static inline void rta_free(rta *r) { if (r && !--r->uc) rta__free(r); }
void rta_dump(rta *);
void rta_dump_all(void);
static inline eattr * rta_find(rta *a, unsigned ea) { return ea_find(a->attrs, ea); }
/*
* Default protocol preferences
*/
#define DEF_PREF_DIRECT 240 /* Directly connected */
#define DEF_PREF_STATIC 200 /* Static route */
#define DEF_PREF_OSPF_INTERNAL 150 /* OSPF intra-area, inter-area and type 1 external routes */
#define DEF_PREF_RIP 120 /* RIP */
#define DEF_PREF_BGP 100 /* BGP */
#define DEF_PREF_OSPF_EXTERNAL 80 /* OSPF external routes */
#define DEF_PREF_RIP_EXTERNAL 70 /* RIP external routes */
#define DEF_PREF_UKR 50 /* Unidentified Kernel Route */
#define DEF_PREF_SINK 10 /* Sink route */
#endif