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1.1 ! misho 1: /* ! 2: * BIRD -- OSPF ! 3: * ! 4: * (c) 1999--2004 Ondrej Filip <feela@network.cz> ! 5: * (c) 2009--2014 Ondrej Zajicek <santiago@crfreenet.org> ! 6: * (c) 2009--2014 CZ.NIC z.s.p.o. ! 7: * ! 8: * Can be freely distributed and used under the terms of the GNU GPL. ! 9: */ ! 10: ! 11: #ifndef _BIRD_OSPF_TOPOLOGY_H_ ! 12: #define _BIRD_OSPF_TOPOLOGY_H_ ! 13: ! 14: struct top_hash_entry ! 15: { /* Index for fast mapping (type,rtrid,LSid)->vertex */ ! 16: snode n; ! 17: node cn; /* For adding into list of candidates ! 18: in intra-area routing table calculation */ ! 19: struct top_hash_entry *next; /* Next in hash chain */ ! 20: struct ospf_lsa_header lsa; ! 21: u16 lsa_type; /* lsa.type processed and converted to common values (LSA_T_*) */ ! 22: u16 init_age; /* Initial value for lsa.age during inst_time */ ! 23: u32 domain; /* Area ID for area-wide LSAs, Iface ID for link-wide LSAs */ ! 24: // struct ospf_area *oa; ! 25: void *lsa_body; /* May be NULL if LSA was flushed but hash entry was kept */ ! 26: void *next_lsa_body; /* For postponed LSA origination */ ! 27: u16 next_lsa_blen; /* For postponed LSA origination */ ! 28: u16 next_lsa_opts; /* For postponed LSA origination */ ! 29: btime inst_time; /* Time of installation into DB */ ! 30: struct ort *nf; /* Reference fibnode for sum and ext LSAs, NULL for otherwise */ ! 31: struct nexthop *nhs; /* Computed nexthops - valid only in ospf_rt_spf() */ ! 32: ip_addr lb; /* In OSPFv2, link back address. In OSPFv3, any global address in the area useful for vlinks */ ! 33: u32 lb_id; /* Interface ID of link back iface (for bcast or NBMA networks) */ ! 34: u32 dist; /* Distance from the root */ ! 35: int ret_count; /* Number of retransmission lists referencing the entry */ ! 36: u8 gr_dirty; /* Local LSA received during GR, will be removed unless reoriginated */ ! 37: u8 color; ! 38: #define OUTSPF 0 ! 39: #define CANDIDATE 1 ! 40: #define INSPF 2 ! 41: u8 mode; /* LSA generated during RT calculation (LSA_RTCALC or LSA_STALE)*/ ! 42: u8 nhs_reuse; /* Whether nhs nodes can be reused during merging. ! 43: See a note in rt.c:add_cand() */ ! 44: }; ! 45: ! 46: ! 47: /* Prevents ospf_hash_find() to ignore the entry, for p->lsrqh and p->lsrth */ ! 48: #define LSA_BODY_DUMMY ((void *) 1) ! 49: ! 50: /* ! 51: * LSA entry life cycle ! 52: * ! 53: * LSA entries are created by ospf_originate_lsa() (for locally originated LSAs) ! 54: * or ospf_install_lsa() (for LSAs received from neighbors). A regular (like ! 55: * newly originated) LSA entry has defined lsa_body nad lsa.age < %LSA_MAXAGE. ! 56: * When the LSA is requested to be flushed by ospf_flush_lsa(), the lsa.age is ! 57: * set to %LSA_MAXAGE and flooded. Flush process is finished asynchronously, ! 58: * when (at least) flooding is acknowledged by neighbors. This is detected in ! 59: * ospf_update_lsadb(), then ospf_clear_lsa() is called to free the LSA body but ! 60: * the LSA entry is kept. Such LSA does not formally exist, we keep an empty ! 61: * entry (until regular timeout) to know inst_time and lsa.sn in the case of ! 62: * later reorigination. After the timeout, LSA is removed by ospf_remove_lsa(). ! 63: * ! 64: * When LSA origination is requested (by ospf_originate_lsa()). but it is not ! 65: * possible to do that immediately (because of MinLSInterval or because the ! 66: * sequence number is wrapping), The new LSA is scheduled for later origination ! 67: * in next_lsa_* fields of the LSA entry. The later origination is handled by ! 68: * ospf_originate_next_lsa() called from ospf_update_lsadb(). We can see that ! 69: * both real origination and final flush is asynchronous to ospf_originate_lsa() ! 70: * and ospf_flush_lsa(). ! 71: * ! 72: * LSA entry therefore could be in three basic states: ! 73: * R - regular (lsa.age < %LSA_MAXAGE, lsa_body != NULL) ! 74: * F - flushing (lsa.age == %LSA_MAXAGE, lsa_body != NULL) ! 75: * E - empty (lsa.age == %LSA_MAXAGE, lsa_body == NULL) ! 76: * ! 77: * And these states are doubled based on whether the next LSA is scheduled ! 78: * (next_lsa_body != NULL, -n suffix) or not (next_lsa_body == NULL). We also ! 79: * use X for a state of non-existentce. We have this basic state graph ! 80: * (transitions from any state to R are omitted for clarity): ! 81: * ! 82: * X --> R ---> F ---> E --> X ! 83: * | \ / | | ! 84: * | \/ | | ! 85: * | /\ | | ! 86: * | / \ | | ! 87: * Rn --> Fn --> En ! 88: * ! 89: * The transitions are: ! 90: * ! 91: * any state -> R - new LSA origination requested and executed ! 92: * R -> Rn, F -> Fn, E -> En - new LSA origination requested and postponed ! 93: * R -> Fn - new LSA origination requested, seqnum wrapping ! 94: * Rn,Fn,En -> R - postponed LSA finally originated ! 95: * R -> R - LSA refresh done ! 96: * R -> Fn - LSA refresh with seqnum wrapping ! 97: * R -> F, Rn -> Fn - LSA age timeout ! 98: * R,Rn,Fn -> F, En -> E - LSA flush requested ! 99: * F -> E, Fn -> En - LSA flush done (acknowledged) ! 100: * E -> X - LSA real age timeout (or immediate for received LSA) ! 101: * ! 102: * The 'origination requested' and 'flush requested' transitions are triggered ! 103: * and done by ospf_originate_lsa() and ospf_flush_lsa(), the rest is handled ! 104: * asynchronously by ospf_update_lsadb(). ! 105: * ! 106: * The situation is significantly simpler for non-local (received) LSAs - there ! 107: * is no postponed origination and after flushing is done, LSAs are immediately ! 108: * removed, so it is just X -> R -> F -> X, or X -> F -> X (when MaxAge LSA is ! 109: * received). ! 110: * ! 111: * There are also some special cases related to handling of received unknown ! 112: * self-originated LSAs in ospf_advance_lsa(): ! 113: * X -> F - LSA is received and immediately flushed ! 114: * R,Rn -> Fn - LSA with MaxSeqNo received and flushed, current LSA scheduled ! 115: */ ! 116: ! 117: ! 118: #define LSA_M_BASIC 0 ! 119: #define LSA_M_EXPORT 1 ! 120: #define LSA_M_RTCALC 2 ! 121: #define LSA_M_EXPORT_STALE 3 ! 122: #define LSA_M_RTCALC_STALE 4 ! 123: ! 124: /* ! 125: * LSA entry modes: ! 126: * ! 127: * LSA_M_BASIC - The LSA is explicitly originated using ospf_originate_lsa() and ! 128: * explicitly flushed using ospf_flush_lsa(). When the LSA is changed, the ! 129: * routing table calculation is scheduled. This is also the mode used for LSAs ! 130: * received from neighbors. Example: Router-LSAs, Network-LSAs. ! 131: * ! 132: * LSA_M_EXPORT - The LSA is originated using ospf_originate_lsa() as a ! 133: * consequence of route export to the OSPF instance. It has to be reoriginated ! 134: * during each channel feed, otherwise it is flushed automatically at the end of ! 135: * the feed. May be originated and flushed asynchronously. Also, routing table ! 136: * calculation does not depend on the LSA. Therefore, the routing table ! 137: * calculation is not scheduled when the LSA is changed. Example: ! 138: * AS-external-LSAs for exported routes. ! 139: * ! 140: * LSA_M_RTCALC - The LSA has to be requested using ospf_originate_lsa() during ! 141: * each routing table calculation, otherwise it is flushed automatically at the ! 142: * end of the calculation. The LSA is a result of the calculation and not a ! 143: * source for it. Therefore, the calculation is not scheduled when the LSA is ! 144: * changed. Example: Summary-LSAs. ! 145: * ! 146: * LSA_M_EXPORT_STALE - Temporary state for LSA_M_EXPORT that is not requested ! 147: * during current external route feed. ! 148: * ! 149: * LSA_M_RTCALC_STALE - Temporary state for LSA_M_RTCALC that is not requested ! 150: * during current routing table calculation. ! 151: * ! 152: * ! 153: * Note that we do not schedule the routing table calculation when the age of ! 154: * LSA_M_BASIC LSA is changed to MaxAge because of the sequence number wrapping, ! 155: * As it will be switched back to a regular one ASAP. ! 156: */ ! 157: ! 158: ! 159: struct top_graph ! 160: { ! 161: pool *pool; /* Pool we allocate from */ ! 162: slab *hash_slab; /* Slab for hash entries */ ! 163: struct top_hash_entry **hash_table; /* Hashing (modelled a`la fib) */ ! 164: uint ospf2; /* Whether it is for OSPFv2 or OSPFv3 */ ! 165: uint hash_size; ! 166: uint hash_order; ! 167: uint hash_mask; ! 168: uint hash_entries; ! 169: uint hash_entries_min, hash_entries_max; ! 170: }; ! 171: ! 172: struct ospf_new_lsa ! 173: { ! 174: u16 type; ! 175: u8 mode; ! 176: u32 dom; ! 177: u32 id; ! 178: u16 opts; ! 179: u16 length; ! 180: struct ospf_iface *ifa; ! 181: struct ort *nf; ! 182: }; ! 183: ! 184: struct top_graph *ospf_top_new(struct ospf_proto *p, pool *pool); ! 185: void ospf_top_free(struct top_graph *f); ! 186: ! 187: struct top_hash_entry * ospf_install_lsa(struct ospf_proto *p, struct ospf_lsa_header *lsa, u32 type, u32 domain, void *body); ! 188: struct top_hash_entry * ospf_originate_lsa(struct ospf_proto *p, struct ospf_new_lsa *lsa); ! 189: void ospf_advance_lsa(struct ospf_proto *p, struct top_hash_entry *en, struct ospf_lsa_header *lsa, u32 type, u32 domain, void *body); ! 190: void ospf_flush_lsa(struct ospf_proto *p, struct top_hash_entry *en); ! 191: void ospf_update_lsadb(struct ospf_proto *p); ! 192: void ospf_feed_begin(struct channel *C, int initial); ! 193: void ospf_feed_end(struct channel *C); ! 194: ! 195: static inline void ospf_flush2_lsa(struct ospf_proto *p, struct top_hash_entry **en) ! 196: { if (*en) { ospf_flush_lsa(p, *en); *en = NULL; } } ! 197: ! 198: void ospf_originate_sum_net_lsa(struct ospf_proto *p, struct ospf_area *oa, ort *nf, int metric); ! 199: void ospf_originate_sum_rt_lsa(struct ospf_proto *p, struct ospf_area *oa, u32 drid, int metric, u32 options); ! 200: void ospf_originate_ext_lsa(struct ospf_proto *p, struct ospf_area *oa, ort *nf, u8 mode, u32 metric, u32 ebit, ip_addr fwaddr, u32 tag, int pbit, int dn); ! 201: void ospf_originate_gr_lsa(struct ospf_proto *p, struct ospf_iface *ifa); ! 202: ! 203: void ospf_rt_notify(struct proto *P, struct channel *ch, net *n, rte *new, rte *old); ! 204: void ospf_update_topology(struct ospf_proto *p); ! 205: ! 206: struct top_hash_entry *ospf_hash_find(struct top_graph *, u32 domain, u32 lsa, u32 rtr, u32 type); ! 207: struct top_hash_entry *ospf_hash_get(struct top_graph *, u32 domain, u32 lsa, u32 rtr, u32 type); ! 208: void ospf_hash_delete(struct top_graph *, struct top_hash_entry *); ! 209: ! 210: static inline struct top_hash_entry * ospf_hash_find_entry(struct top_graph *f, struct top_hash_entry *en) ! 211: { return ospf_hash_find(f, en->domain, en->lsa.id, en->lsa.rt, en->lsa_type); } ! 212: ! 213: static inline struct top_hash_entry * ospf_hash_get_entry(struct top_graph *f, struct top_hash_entry *en) ! 214: { return ospf_hash_get(f, en->domain, en->lsa.id, en->lsa.rt, en->lsa_type); } ! 215: ! 216: struct top_hash_entry * ospf_hash_find_rt(struct top_graph *f, u32 domain, u32 rtr); ! 217: struct top_hash_entry * ospf_hash_find_rt3_first(struct top_graph *f, u32 domain, u32 rtr); ! 218: struct top_hash_entry * ospf_hash_find_rt3_next(struct top_hash_entry *e); ! 219: ! 220: struct top_hash_entry * ospf_hash_find_net2(struct top_graph *f, u32 domain, u32 id); ! 221: ! 222: /* In OSPFv2, id is network IP prefix (lsa.id) while lsa.rt field is unknown ! 223: In OSPFv3, id is lsa.rt of DR while nif is neighbor iface id (lsa.id) */ ! 224: static inline struct top_hash_entry * ! 225: ospf_hash_find_net(struct top_graph *f, u32 domain, u32 id, u32 nif) ! 226: { ! 227: return f->ospf2 ? ! 228: ospf_hash_find_net2(f, domain, id) : ! 229: ospf_hash_find(f, domain, nif, id, LSA_T_NET); ! 230: } ! 231: ! 232: ! 233: #endif /* _BIRD_OSPF_TOPOLOGY_H_ */