diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/event_test.c | 2 | ||||
-rw-r--r-- | lib/route.h | 334 |
2 files changed, 335 insertions, 1 deletions
diff --git a/lib/event_test.c b/lib/event_test.c index e1fbea8f..e14d0b95 100644 --- a/lib/event_test.c +++ b/lib/event_test.c @@ -15,7 +15,7 @@ #include "nest/locks.h" #include "sysdep/unix/unix.h" #include "nest/iface.h" -#include "nest/route.h" +#include "nest/rt.h" #define MAX_NUM 4 diff --git a/lib/route.h b/lib/route.h new file mode 100644 index 00000000..20b6fd39 --- /dev/null +++ b/lib/route.h @@ -0,0 +1,334 @@ +/* + * BIRD Internet Routing Daemon -- Routing data structures + * + * (c) 1998--2000 Martin Mares <mj@ucw.cz> + * (c) 2022 Maria Matejka <mq@jmq.cz> + * + * Can be freely distributed and used under the terms of the GNU GPL. + */ + +#ifndef _BIRD_LIB_ROUTE_H_ +#define _BIRD_LIB_ROUTE_H_ + +struct network; +struct proto; +struct cli; + + +typedef struct rte { + struct rta *attrs; /* Attributes of this route */ + const net_addr *net; /* Network this RTE belongs to */ + struct rte_src *src; /* Route source that created the route */ + struct rt_import_hook *sender; /* Import hook used to send the route to the routing table */ + btime lastmod; /* Last modified (set by table) */ + u32 id; /* Table specific route id */ + byte flags; /* Table-specific flags */ + byte pflags; /* Protocol-specific flags */ + u8 generation; /* If this route import is based on other previously exported route, + this value should be 1 + MAX(generation of the parent routes). + Otherwise the route is independent and this value is zero. */ +} rte; + +#define REF_FILTERED 2 /* Route is rejected by import filter */ +#define REF_STALE 4 /* Route is stale in a refresh cycle */ +#define REF_DISCARD 8 /* Route is scheduled for discard */ +#define REF_MODIFY 16 /* Route is scheduled for modify */ + +/* Route is valid for propagation (may depend on other flags in the future), accepts NULL */ +static inline int rte_is_valid(rte *r) { return r && !(r->flags & REF_FILTERED); } + +/* Route just has REF_FILTERED flag */ +static inline int rte_is_filtered(rte *r) { return !!(r->flags & REF_FILTERED); } + +struct rte_src { + struct rte_src *next; /* Hash chain */ + struct proto *proto; /* Protocol the source is based on */ + u32 private_id; /* Private ID, assigned by the protocol */ + u32 global_id; /* Globally unique ID of the source */ + unsigned uc; /* Use count */ +}; + + +struct rte_src *rt_find_source(struct proto *p, u32 id); +struct rte_src *rt_get_source(struct proto *p, u32 id); +static inline void rt_lock_source(struct rte_src *src) { src->uc++; } +static inline void rt_unlock_source(struct rte_src *src) { src->uc--; } +void rt_prune_sources(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. + */ + +/* Nexthop structure */ +struct nexthop { + ip_addr gw; /* Next hop */ + struct iface *iface; /* Outgoing interface */ + struct nexthop *next; + byte flags; + byte weight; + byte labels_orig; /* Number of labels before hostentry was applied */ + byte labels; /* Number of all labels */ + u32 label[0]; +}; + +#define RNF_ONLINK 0x1 /* Gateway is onlink regardless of IP ranges */ + + +typedef struct rta { + struct rta *next, **pprev; /* Hash chain */ + u32 uc; /* Use count */ + u32 hash_key; /* Hash over important fields */ + struct ea_list *eattrs; /* Extended Attribute chain */ + struct hostentry *hostentry; /* Hostentry for recursive next-hops */ + ip_addr from; /* Advertising router */ + u32 igp_metric; /* IGP metric to next hop (for iBGP routes) */ + u16 cached:1; /* Are attributes cached? */ + u16 source:7; /* Route source (RTS_...) */ + u16 scope:4; /* Route scope (SCOPE_... -- see ip.h) */ + u16 dest:4; /* Route destination type (RTD_...) */ + word pref; + struct nexthop nh; /* Next hop */ +} rta; + +#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_OSPF 7 /* OSPF route */ +#define RTS_OSPF_IA 8 /* OSPF inter-area route */ +#define RTS_OSPF_EXT1 9 /* OSPF external route type 1 */ +#define RTS_OSPF_EXT2 10 /* OSPF external route type 2 */ +#define RTS_BGP 11 /* BGP route */ +#define RTS_PIPE 12 /* Inter-table wormhole */ +#define RTS_BABEL 13 /* Babel route */ +#define RTS_RPKI 14 /* Route Origin Authorization */ +#define RTS_PERF 15 /* Perf checker */ +#define RTS_MAX 16 + +#define RTD_NONE 0 /* Undefined next hop */ +#define RTD_UNICAST 1 /* Next hop is neighbor router */ +#define RTD_BLACKHOLE 2 /* Silently drop packets */ +#define RTD_UNREACHABLE 3 /* Reject as unreachable */ +#define RTD_PROHIBIT 4 /* Administratively prohibited */ +#define RTD_MAX 5 + +#define IGP_METRIC_UNKNOWN 0x80000000 /* Default igp_metric used when no other + protocol-specific metric is availabe */ + + +extern const char * rta_dest_names[RTD_MAX]; + +static inline const char *rta_dest_name(uint n) +{ return (n < RTD_MAX) ? rta_dest_names[n] : "???"; } + +/* Route has regular, reachable nexthop (i.e. not RTD_UNREACHABLE and like) */ +static inline int rte_is_reachable(rte *r) +{ return r->attrs->dest == RTD_UNICAST; } + + +/* + * Extended Route Attributes + */ + +typedef struct eattr { + word id; /* EA_CODE(PROTOCOL_..., protocol-dependent ID) */ + byte flags; /* Protocol-dependent flags */ + byte type:5; /* Attribute type */ + byte originated:1; /* The attribute has originated locally */ + byte fresh:1; /* An uncached attribute (e.g. modified in export filter) */ + byte undef:1; /* Explicitly undefined */ + + union bval u; +} eattr; + + +#define EA_CODE(proto,id) (((proto) << 8) | (id)) +#define EA_ID(ea) ((ea) & 0xff) +#define EA_PROTO(ea) ((ea) >> 8) +#define EA_CUSTOM(id) ((id) | EA_CUSTOM_BIT) +#define EA_IS_CUSTOM(ea) ((ea) & EA_CUSTOM_BIT) +#define EA_CUSTOM_ID(ea) ((ea) & ~EA_CUSTOM_BIT) + +const char *ea_custom_name(uint ea); + +#define EA_GEN_IGP_METRIC EA_CODE(PROTOCOL_NONE, 0) + +#define EA_CODE_MASK 0xffff +#define EA_CUSTOM_BIT 0x8000 +#define EA_ALLOW_UNDEF 0x10000 /* ea_find: allow EAF_TYPE_UNDEF */ +#define EA_BIT(n) ((n) << 24) /* Used in bitfield accessors */ +#define EA_BIT_GET(ea) ((ea) >> 24) + +typedef struct adata { + uint length; /* Length of data */ + byte data[0]; +} adata; + +extern const adata null_adata; /* adata of length 0 */ + +static inline struct adata * +lp_alloc_adata(struct linpool *pool, uint len) +{ + struct adata *ad = lp_alloc(pool, sizeof(struct adata) + len); + ad->length = len; + return ad; +} + +static inline int adata_same(const struct adata *a, const struct adata *b) +{ return (a->length == b->length && !memcmp(a->data, b->data, a->length)); } + + +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 */ + +struct ea_walk_state { + ea_list *eattrs; /* Ccurrent ea_list, initially set by caller */ + eattr *ea; /* Current eattr, initially NULL */ + u32 visited[4]; /* Bitfield, limiting max to 128 */ +}; + +eattr *ea_find(ea_list *, unsigned ea); +eattr *ea_walk(struct ea_walk_state *s, uint id, uint max); + +/** + * ea_get_int - fetch an integer attribute + * @e: attribute list + * @id: attribute ID + * @def: default value + * + * This function is a shortcut for retrieving a value of an integer attribute + * by calling ea_find() to find the attribute, extracting its value or returning + * a provided default if no such attribute is present. + */ +static inline u32 +ea_get_int(ea_list *e, unsigned id, u32 def) +{ + eattr *a = ea_find(e, id); + return a ? a->u.data : def; +} + +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 */ +void ea_merge(ea_list *from, ea_list *to); /* Merge sub-lists to allocated buffer */ +int ea_same(ea_list *x, ea_list *y); /* Test whether two ea_lists are identical */ +uint ea_hash(ea_list *e); /* Calculate 16-bit hash value */ +ea_list *ea_append(ea_list *to, ea_list *what); +void ea_format_bitfield(const struct eattr *a, byte *buf, int bufsize, const char **names, int min, int max); + +#define ea_normalize(ea) do { \ + if (ea->next) { \ + ea_list *t = alloca(ea_scan(ea)); \ + ea_merge(ea, t); \ + ea = t; \ + } \ + ea_sort(ea); \ + if (ea->count == 0) \ + ea = NULL; \ +} while(0) \ + +struct ea_one_attr_list { + ea_list l; + eattr a; +}; + +static inline eattr * +ea_set_attr(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, union bval val) +{ + struct ea_one_attr_list *ea = lp_alloc(pool, sizeof(*ea)); + *ea = (struct ea_one_attr_list) { + .l.flags = EALF_SORTED, + .l.count = 1, + .l.next = *to, + + .a.id = id, + .a.type = type, + .a.flags = flags, + }; + + ea->a.u = val; + *to = &ea->l; + + return &ea->a; +} + +static inline void +ea_unset_attr(ea_list **to, struct linpool *pool, _Bool local, uint code) +{ + struct ea_one_attr_list *ea = lp_alloc(pool, sizeof(*ea)); + *ea = (struct ea_one_attr_list) { + .l.flags = EALF_SORTED, + .l.count = 1, + .l.next = *to, + .a.id = code, + .a.fresh = local, + .a.originated = local, + .a.undef = 1, + }; + + *to = &ea->l; +} + +static inline void +ea_set_attr_u32(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, u32 data) +{ + union bval bv = { .data = data }; + ea_set_attr(to, pool, id, flags, type, bv); +} + +static inline void +ea_set_attr_data(ea_list **to, struct linpool *pool, uint id, uint flags, uint type, void *data, uint len) +{ + struct adata *a = lp_alloc_adata(pool, len); + memcpy(a->data, data, len); + union bval bv = { .ptr = a, }; + ea_set_attr(to, pool, id, flags, type, bv); +} + + +#define NEXTHOP_MAX_SIZE (sizeof(struct nexthop) + sizeof(u32)*MPLS_MAX_LABEL_STACK) + +static inline size_t nexthop_size(const struct nexthop *nh) +{ return sizeof(struct nexthop) + sizeof(u32)*nh->labels; } +int nexthop__same(struct nexthop *x, struct nexthop *y); /* Compare multipath nexthops */ +static inline int nexthop_same(struct nexthop *x, struct nexthop *y) +{ return (x == y) || nexthop__same(x, y); } +struct nexthop *nexthop_merge(struct nexthop *x, struct nexthop *y, int rx, int ry, int max, linpool *lp); +struct nexthop *nexthop_sort(struct nexthop *x); +static inline void nexthop_link(struct rta *a, struct nexthop *from) +{ memcpy(&a->nh, from, nexthop_size(from)); } +void nexthop_insert(struct nexthop **n, struct nexthop *y); +int nexthop_is_sorted(struct nexthop *x); + +void rta_init(void); +static inline size_t rta_size(const rta *a) { return sizeof(rta) + sizeof(u32)*a->nh.labels; } +#define RTA_MAX_SIZE (sizeof(rta) + sizeof(u32)*MPLS_MAX_LABEL_STACK) +rta *rta_lookup(rta *); /* Get rta equivalent to this one, uc++ */ +static inline int rta_is_cached(rta *r) { return r->cached; } +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); } +rta *rta_do_cow(rta *o, linpool *lp); +static inline rta * rta_cow(rta *r, linpool *lp) { return rta_is_cached(r) ? rta_do_cow(r, lp) : r; } +void rta_dump(rta *); +void rta_dump_all(void); +void rta_show(struct cli *, rta *); + +u32 rt_get_igp_metric(rte *rt); + +#endif |