--- configure.in | 4 +- filter/config.Y | 2 +- filter/filter.h | 7 +- filter/trie.c | 111 +++++++- nest/proto-hooks.c | 11 + nest/proto.c | 3 + nest/protocol.h | 9 +- nest/rt-table.c | 19 +- proto/agg/Doc | 1 + proto/agg/Makefile | 6 + proto/agg/agg.c | 685 +++++++++++++++++++++++++++++++++++++++++++++ proto/agg/agg.h | 81 ++++++ proto/agg/config.Y | 99 +++++++ proto/bgp/attrs.c | 754 ++++++++++++++++++++++++++++++++++++++++++++++++++ proto/bgp/bgp.c | 7 +- proto/bgp/bgp.h | 2 + sysdep/autoconf.h.in | 1 + 17 files changed, 1778 insertions(+), 24 deletions(-) create mode 100644 proto/agg/Doc create mode 100644 proto/agg/Makefile create mode 100644 proto/agg/agg.c create mode 100644 proto/agg/agg.h create mode 100644 proto/agg/config.Y diff --git a/configure.in b/configure.in index 46a6ecd..aff445a 100644 --- a/configure.in +++ b/configure.in @@ -43,11 +43,11 @@ AC_SUBST(srcdir_rel_mf) if test "$enable_ipv6" = yes ; then ip=ipv6 SUFFIX6=6 - all_protocols=bgp,ospf,pipe,radv,rip,static + all_protocols=bgp,ospf,pipe,radv,rip,static,agg else ip=ipv4 SUFFIX6="" - all_protocols=bgp,ospf,pipe,rip,static + all_protocols=bgp,ospf,pipe,rip,static,agg fi if test "$with_protocols" = all ; then diff --git a/filter/config.Y b/filter/config.Y index 0166d27..4c6dc48 100644 --- a/filter/config.Y +++ b/filter/config.Y @@ -557,7 +557,7 @@ fprefix: ; fprefix_set: - fprefix { $$ = f_new_trie(cfg_mem); trie_add_fprefix($$, &($1.val.px)); } + fprefix { $$ = f_new_trie(cfg_mem, sizeof(struct f_trie_node)); trie_add_fprefix($$, &($1.val.px)); } | fprefix_set ',' fprefix { $$ = $1; trie_add_fprefix($$, &($3.val.px)); } ; diff --git a/filter/filter.h b/filter/filter.h index 2cf4652..4c60abe 100644 --- a/filter/filter.h +++ b/filter/filter.h @@ -71,11 +71,13 @@ struct f_tree *build_tree(struct f_tree *); struct f_tree *find_tree(struct f_tree *t, struct f_val val); int same_tree(struct f_tree *t1, struct f_tree *t2); -struct f_trie *f_new_trie(linpool *lp); -void trie_add_prefix(struct f_trie *t, ip_addr px, int plen, int l, int h); +struct f_trie *f_new_trie(linpool *lp, size_t node_size); +void *trie_add_prefix(struct f_trie *t, ip_addr px, int plen, int l, int h); int trie_match_prefix(struct f_trie *t, ip_addr px, int plen); +void *trie_match_longest_prefix(struct f_trie *t, ip_addr px, int plen); int trie_same(struct f_trie *t1, struct f_trie *t2); void trie_print(struct f_trie *t); +void trie_walk(struct f_trie *t, void *func, void *data); void fprefix_get_bounds(struct f_prefix *px, int *l, int *h); @@ -177,6 +179,7 @@ struct f_trie { linpool *lp; int zero; + size_t node_size; struct f_trie_node root; }; diff --git a/filter/trie.c b/filter/trie.c index 581332c..12d7755 100644 --- a/filter/trie.c +++ b/filter/trie.c @@ -75,23 +75,24 @@ #include "filter/filter.h" /** - * f_new_trie - * - * Allocates and returns a new empty trie. + * f_new_trie - Allocates and returns a new empty trie. + * @lp: linear pool to allocate items from + * @node_size: element size to allocate */ struct f_trie * -f_new_trie(linpool *lp) +f_new_trie(linpool *lp, size_t node_size) { struct f_trie * ret; - ret = lp_allocz(lp, sizeof(struct f_trie)); + ret = lp_allocz(lp, sizeof(struct f_trie) + node_size - sizeof(struct f_trie_node)); ret->lp = lp; + ret->node_size = node_size; return ret; } static inline struct f_trie_node * new_node(struct f_trie *t, int plen, ip_addr paddr, ip_addr pmask, ip_addr amask) { - struct f_trie_node *n = lp_allocz(t->lp, sizeof(struct f_trie_node)); + struct f_trie_node *n = lp_allocz(t->lp, t->node_size); n->plen = plen; n->addr = paddr; n->mask = pmask; @@ -116,9 +117,13 @@ attach_node(struct f_trie_node *parent, struct f_trie_node *child) * Adds prefix (prefix pattern) @px/@plen to trie @t. @l and @h are lower * and upper bounds on accepted prefix lengths, both inclusive. * 0 <= l, h <= 32 (128 for IPv6). + * + * Returns pointer to allocated node. Function can return pointer to + * existing node if @px and @plen are the same. If px/plen == 0/0 (or ::/0) + * pointer to root node is returned */ -void +void * trie_add_prefix(struct f_trie *t, ip_addr px, int plen, int l, int h) { if (l == 0) @@ -156,7 +161,7 @@ trie_add_prefix(struct f_trie *t, ip_addr px, int plen, int l, int h) attach_node(o, b); attach_node(b, n); attach_node(b, a); - return; + return a; } if (plen < n->plen) @@ -166,14 +171,14 @@ trie_add_prefix(struct f_trie *t, ip_addr px, int plen, int l, int h) struct f_trie_node *a = new_node(t, plen, paddr, pmask, amask); attach_node(o, a); attach_node(a, n); - return; + return a; } if (plen == n->plen) { /* We already found added node in trie. Just update accept mask */ n->accept = ipa_or(n->accept, amask); - return; + return n; } /* Update accept mask part M2 and go deeper */ @@ -187,6 +192,8 @@ trie_add_prefix(struct f_trie *t, ip_addr px, int plen, int l, int h) /* We add new tail node 'a' after node 'o' */ struct f_trie_node *a = new_node(t, plen, paddr, pmask, amask); attach_node(o, a); + + return a; } /** @@ -234,6 +241,90 @@ trie_match_prefix(struct f_trie *t, ip_addr px, int plen) return 0; } +#define NODE_IS_BRANCHING(x) (*((u32 *)(((struct f_trie_node *)(x)) + 1)) == 0) +/** + * trie_match_longest_prefix - find longest prefix match + * @t: trie + * @px: prefix address + * @plen: prefix length + * + * Tries to find a matching prefix pattern in the trie such that + * prefix @px/@plen matches that prefix pattern. Returns 1 if there + * is such prefix pattern in the trie. + */ +void * +trie_match_longest_prefix(struct f_trie *t, ip_addr px, int plen) +{ + ip_addr pmask = ipa_mkmask(plen); + ip_addr paddr = ipa_and(px, pmask); + ip_addr cmask; + struct f_trie_node *n = &t->root, *parent = NULL; + + /* Skip root node since it is cath-all node */ + n = n->c[(ipa_getbit(paddr, 0)) ? 1 : 0]; + + while (n) + { + cmask = ipa_and(n->mask, pmask); + + /* We are out of path */ + if (ipa_compare(ipa_and(paddr, cmask), ipa_and(n->addr, cmask))) + break; + + /* Mask is too specific */ + if (n->plen > plen) + break; + + /* Do not save pointer to branching nodes */ + if (!NODE_IS_BRANCHING(n)) + parent = n; + + /* Choose children */ + n = n->c[(ipa_getbit(paddr, n->plen)) ? 1 : 0]; + } + + /* + * parent is either + * 1) NULL (if the first non-null node does not exist oris out of path) + * or + * 2) points to the last entry that match + * + * In former case we check if catch-all prefix really exists and return + * either pointer to root node or NULL. In latter case we simply return parent. + */ + + return parent ? parent : (t->zero ? &t->root : NULL); +} + +static void +trie_walk_call(struct f_trie_node *n, void *func, void *data) +{ + void (*f)(struct f_trie_node *, void *) = func; + + if (n) + f(n, data); + + if (n->c[0]) + trie_walk_call(n->c[0], func, data); + + if (n->c[1]) + trie_walk_call(n->c[1], func, data); +} + +void +trie_walk(struct f_trie *t, void *func, void *data) +{ + void (*f)(struct f_trie_node *, void *) = func; + + if (t->zero) + f(&t->root, data); + + if (t->root.c[0]) + trie_walk_call(t->root.c[0], func, data); + if (t->root.c[1]) + trie_walk_call(t->root.c[1], func, data); +} + static int trie_node_same(struct f_trie_node *t1, struct f_trie_node *t2) { diff --git a/nest/proto-hooks.c b/nest/proto-hooks.c index 2582c48..1b59fbb 100644 --- a/nest/proto-hooks.c +++ b/nest/proto-hooks.c @@ -150,6 +150,17 @@ int get_attr(eattr *a, byte *buf, int buflen) { DUMMY; } /** + * get_route_ainfo - get additional route information + * @c: pointer to cli + * @cli_val: cli format value + * @e: a route entry + * + * This hook is called after printing extended route attributes + */ +void get_route_ainfo(struct cli *c, int cli_val, rte *e) +{ DUMMY; } + +/** * if_notify - notify instance about interface changes * @p: protocol instance * @flags: interface change flags diff --git a/nest/proto.c b/nest/proto.c index 0fc72ce..a48656c 100644 --- a/nest/proto.c +++ b/nest/proto.c @@ -633,6 +633,9 @@ protos_build(void) #ifdef CONFIG_BGP proto_build(&proto_bgp); #endif +#ifdef CONFIG_AGG + proto_build(&proto_agg); +#endif proto_pool = rp_new(&root_pool, "Protocols"); proto_flush_event = ev_new(proto_pool); proto_flush_event->hook = proto_flush_all; diff --git a/nest/protocol.h b/nest/protocol.h index a83c4ff..e61b8d3 100644 --- a/nest/protocol.h +++ b/nest/protocol.h @@ -28,6 +28,10 @@ struct event; struct ea_list; struct eattr; struct symbol; +struct agg_sumroute; +struct agg_route; +struct agg_proto; +struct cli; /* * Routing Protocol @@ -53,8 +57,11 @@ struct protocol { void (*get_status)(struct proto *, byte *buf); /* Get instance status (for `show protocols' command) */ void (*get_route_info)(struct rte *, byte *buf, struct ea_list *attrs); /* Get route information (for `show route' command) */ int (*get_attr)(struct eattr *, byte *buf, int buflen); /* ASCIIfy dynamic attribute (returns GA_*) */ + void (*create_sumroute)(struct agg_proto *, struct agg_sumroute *); /* Create summary route */ + void (*update_sumroute)(struct agg_proto *, struct agg_sumroute *, struct agg_route *, struct rta *, struct rta *); /* Update summary route */ void (*show_proto_info)(struct proto *); /* Show protocol info (for `show protocols all' command) */ void (*copy_config)(struct proto_config *, struct proto_config *); /* Copy config from given protocol instance */ + void (*get_route_ainfo)(struct cli *, int, struct rte *); /* Print additional information (for `show route' command) */ }; void protos_build(void); @@ -74,7 +81,7 @@ void protos_dump_all(void); extern struct protocol proto_device, proto_radv, proto_rip, proto_static, - proto_ospf, proto_pipe, proto_bgp; + proto_ospf, proto_pipe, proto_bgp, proto_agg; /* * Routing Protocol Instance diff --git a/nest/rt-table.c b/nest/rt-table.c index 377687d..4709544 100644 --- a/nest/rt-table.c +++ b/nest/rt-table.c @@ -1440,7 +1440,7 @@ rt_init_hostcache(rtable *tab) hc->slab = sl_new(rt_table_pool, sizeof(struct hostentry)); hc->lp = lp_new(rt_table_pool, 1008); - hc->trie = f_new_trie(hc->lp); + hc->trie = f_new_trie(hc->lp, sizeof(struct f_trie_node)); tab->hostcache = hc; } @@ -1587,7 +1587,7 @@ rt_update_hostcache(rtable *tab) /* Reset the trie */ lp_flush(hc->lp); - hc->trie = f_new_trie(hc->lp); + hc->trie = f_new_trie(hc->lp, sizeof(struct f_trie_node)); WALK_LIST_DELSAFE(n, x, hc->hostentries) { @@ -1634,7 +1634,7 @@ rta_set_recursive_next_hop(rtable *dep, rta *a, rtable *tab, ip_addr *gw, ip_add * CLI commands */ -static void +void rt_format_via(rte *e, byte *via) { rta *a = e->attrs; @@ -1660,6 +1660,7 @@ rt_show_rte(struct cli *c, byte *ia, rte *e, struct rt_show_data *d, ea_list *tm int primary = (e->net->routes == e); int sync_error = (e->net->n.flags & KRF_SYNC_ERROR); struct mpnh *nh; + struct protocol *P = a->proto->proto; rt_format_via(e, via); tm_format_datetime(tm, &config->tf_route, e->lastmod); @@ -1667,7 +1668,7 @@ rt_show_rte(struct cli *c, byte *ia, rte *e, struct rt_show_data *d, ea_list *tm bsprintf(from, " from %I", a->from); else from[0] = 0; - if (a->proto->proto->get_route_info || d->verbose) + if (P->get_route_info || d->verbose) { /* Need to normalize the extended attributes */ ea_list *t = tmpa; @@ -1676,8 +1677,8 @@ rt_show_rte(struct cli *c, byte *ia, rte *e, struct rt_show_data *d, ea_list *tm ea_merge(t, tmpa); ea_sort(tmpa); } - if (a->proto->proto->get_route_info) - a->proto->proto->get_route_info(e, info, tmpa); + if (P->get_route_info) + P->get_route_info(e, info, tmpa); else bsprintf(info, " (%d)", e->pref); cli_printf(c, -1007, "%-18s %s [%s %s%s]%s%s", ia, via, a->proto->name, @@ -1685,7 +1686,11 @@ rt_show_rte(struct cli *c, byte *ia, rte *e, struct rt_show_data *d, ea_list *tm for (nh = a->nexthops; nh; nh = nh->next) cli_printf(c, -1007, "\tvia %I on %s weight %d", nh->gw, nh->iface->name, nh->weight + 1); if (d->verbose) - rta_show(c, a, tmpa); + { + rta_show(c, a, tmpa); + if (P->get_route_ainfo) + P->get_route_ainfo(c, -1007, e); + } } static void diff --git a/proto/agg/Doc b/proto/agg/Doc new file mode 100644 index 0000000..486cd10 --- /dev/null +++ b/proto/agg/Doc @@ -0,0 +1 @@ +S agg.c diff --git a/proto/agg/Makefile b/proto/agg/Makefile new file mode 100644 index 0000000..3039207 --- /dev/null +++ b/proto/agg/Makefile @@ -0,0 +1,6 @@ +source=agg.c +root-rel=../../ +dir-name=proto/agg + +include ../../Rules + diff --git a/proto/agg/agg.c b/proto/agg/agg.c new file mode 100644 index 0000000..d7faba6 --- /dev/null +++ b/proto/agg/agg.c @@ -0,0 +1,685 @@ +/* + * BIRD -- BGP route aggregation + * + * (c) 2012 Yandex LLC + * (c) 2012 Alexander V. Chernikov <melifaro@yandex-team.ru> + * + * Can be freely distributed and used under the terms of the GNU GPL. + */ + +/** + * DOC: Route aggregation + * + * Firewall protocol is very simple. It adds or removes exported routes to given firewall + * table with zero (or filter-specified) value. Table can be flushed on startup to + * avoid error messages on bird restart. + */ + + +#undef LOCAL_DEBUG + +#include "nest/bird.h" +#include "nest/iface.h" +#include "nest/protocol.h" +#include "nest/route.h" +#include "conf/conf.h" +#include "nest/cli.h" +#include "filter/filter.h" +#include "lib/string.h" + +#include "proto/agg/agg.h" + +#define ADBG(msg, ...) DBG("%s:%d " msg "\n", __FUNCTION__, __LINE__, ##__VA_ARGS__) + +static void agg_init_sumroute(struct agg_proto *p, struct agg_sumroute *asr); +static void agg_mark_sumroute(struct f_trie_node *n, void *data UNUSED); +static void agg_update_sumroute(struct agg_proto *p, struct agg_sumroute *asr, struct agg_route *ar, rta *old, rta *new); +static void agg_announce_sumroute(struct agg_proto *p, struct agg_sumroute *asr); + +static int +agg_import_control(struct proto *P, rte **ee, ea_list **ea UNUSED, struct linpool *p UNUSED) +{ + struct proto *pp = (*ee)->sender; + + if (pp == P) + return -1; /* Avoid local loops automatically */ + return 0; +} + +static int +agg_reload_routes(struct proto *P) +{ + return 1; +} + +static void +agg_initroute(struct fib_node *fn) +{ + struct agg_route *ar = (struct agg_route *)fn; + + memset((byte *)ar + sizeof(struct fib_node), 0, sizeof(struct agg_route) - sizeof(struct fib_node)); + ar->flags = AGG_FLAG_NEW; +} + +static int +agg_can_announce(struct agg_sumroute *asr) +{ + return (asr->mandatory_current == asr->mandatory_total); +} + +/* + * agg_make_route - create new route + * @p: protocol instance + * @addr: pointer to network address + * @plen: prefix length + * + * Adds mandatory route to fib and links it to + */ +static struct agg_route * +agg_make_route(struct agg_proto *p, ip_addr *addr, int plen) +{ + struct agg_route *ar = fib_get(&p->route_fib, addr, plen); + + if (ar->flags & AGG_FLAG_NEW) + { + /* New route. Do init */ + init_list(&ar->sum_membership); + ar->flags &= ~AGG_FLAG_NEW; + } + + return ar; +} + +static void +agg_link_mroute(struct agg_proto *p, struct agg_sumroute *asr, struct agg_route *ar) +{ + struct agg_membership *ms; + + ms = mb_alloc(p->p.pool, sizeof(struct agg_membership)); + ms->ar = ar; + ms->asr = asr; + + ADBG("Linking mandatory route %I/%d to summary %I/%d", ar->fn.prefix, ar->fn.pxlen, asr->tn.addr, asr->tn.plen); + + add_tail(&ar->sum_membership, &ms->n_mandatory); + add_tail(&asr->mandatory_list, &ms->n_sumroute); +} + +static void +agg_unlink_mroute(struct agg_proto *p, struct agg_membership *ms) +{ + struct agg_route *ar = ms->ar; + + ADBG("Unlinking mandatory route %I/%d from summary %I/%d", ar->fn.prefix, ar->fn.pxlen, ms->asr->tn.addr, ms->asr->tn.plen); + + rem_node(&ms->n_mandatory); + rem_node(&ms->n_sumroute); + mb_free(ms); + + /* Check if we need to free route iself */ + if (!EMPTY_LIST(ar->sum_membership)) + return; + + if (ar->attrs) + return; + + /* No other mandatory routes, no route entry. We can safely free node */ + fib_delete(&p->route_fib, ar); +} + +static void +agg_walk_sumroutes_initial(struct f_trie_node *n, void *data) +{ + struct agg_sumroute *asr = (struct agg_sumroute *)n; + struct agg_proto *p = (struct agg_proto *)data; + + if (!(asr->flags & AGG_FLAG_PREPARED)) + return; + + agg_init_sumroute(p, asr); +} + +static int +agg_start(struct proto *P) +{ + struct agg_proto *p = (struct agg_proto *)P; + struct agg_config *cf = (struct agg_config *)P->cf; + + fib_init(&p->route_fib, P->pool, sizeof(struct agg_route), 0, agg_initroute); + p->summary_trie = cf->summary_trie; + + /* Import mandatory routes if any */ + trie_walk(p->summary_trie, agg_walk_sumroutes_initial, p); + + /* Allocate by 16k blocks (while BGP requests 1k block) */ + p->lp = lp_new(P->pool, 16384 - 16); + + return PS_UP; +} + +/* + * Mark given summary route as deleted + */ +static void +agg_mark_sumroute(struct f_trie_node *n, void *data UNUSED) +{ + struct agg_sumroute *asr = (struct agg_sumroute *)n; + + if (!(asr->flags & AGG_FLAG_PREPARED)) + return; + + asr->flags |= AGG_FLAG_DELETED; +} + +/* + * Initialize newly-allocated summary route. Add all mandatory routes + * to protocol FIB + */ +static void +agg_init_sumroute(struct agg_proto *p, struct agg_sumroute *asr) +{ + struct cf_route *cr; + struct agg_route *ar; + node *n, *n_next; + + ADBG("New summary route %I/%d", asr->tn.addr, asr->tn.plen); + + /* New summary route. Let's add mandatory routes to our fib */ + WALK_LIST_DELSAFE(n, n_next, asr->cf_routes) + { + cr = (struct cf_route *)n; + + /* In any case, we need to increase count of mandatory routes */ + asr->mandatory_total++; + + /* Get or create new route entry */ + ar = agg_make_route(p, &cr->px.addr, cr->px.len); + + /* Increate current counter IFF we have real best rte associated with entry */ + if (ar->attrs) + { + asr->mandatory_current++; + /* Set installed flag */ + ar->flags |= AGG_FLAG_INSTALLED; + } + + /* Add link */ + agg_link_mroute(p, asr, ar); + } +} + +static void +agg_announce_sumroute(struct agg_proto *p, struct agg_sumroute *asr) +{ + //net *n; + + if (!agg_can_announce(asr)) + return; + + if (EMPTY_LIST(asr->routes)) + return; + + /* Generate summary route */ + switch (asr->route_src) + { +#ifdef CONFIG_BGP + case RTS_BGP: + proto_bgp.create_sumroute(p, asr); + break; +#endif + } +} + +static void +agg_withdraw_sumroute(struct agg_proto *p, struct agg_sumroute *asr) +{ + net *n; + + /* Withdraw route if any */ + if (asr->attrs) + { + ADBG("Withdraw summary %I/%d", asr->tn.addr, asr->tn.plen); + if (n = fib_find(&p->p.table->fib, &asr->tn.addr, asr->tn.plen)) + rte_update(p->p.table, n, &p->p, &p->p, NULL); + + /* Free rta */ + rta_free(asr->attrs); + asr->attrs = NULL; + } +} + +static void +agg_update_sumroute(struct agg_proto *p, struct agg_sumroute *asr, struct agg_route *ar, rta *old, rta *new) +{ + switch (asr->route_src) + { +#ifdef CONFIG_BGP + case RTS_BGP: + proto_bgp.update_sumroute(p, asr, ar, old, new); + break; +#endif + } +} + +/* + * Remove non-config data associated with summary route + */ +static void +agg_clear_sumroute(struct f_trie_node *tn, void *P) +{ + struct agg_proto *p = (struct agg_proto *)P; + struct agg_sumroute *asr = (struct agg_sumroute *)tn; + struct agg_membership *ms; + struct agg_route *ar; + node *n, *n_next; + + if (!(asr->flags & AGG_FLAG_PREPARED)) + return; + + if (!(asr->flags & AGG_FLAG_DELETED)) + return; + + ADBG("Removing summary %I/%d", asr->tn.addr, asr->tn.plen); + /* Remove mandatory routes (allocated from protocol pool) */ + WALK_LIST_DELSAFE(n, n_next, asr->mandatory_list) + { + ms = SKIP_BACK(struct agg_membership, n_sumroute, n); + agg_unlink_mroute(p, ms); + } + + WALK_LIST_DELSAFE(n, n_next, asr->routes) + { + ar = SKIP_BACK(struct agg_route, n_sumroute, n); + + rem_node(&ar->n_sumroute); + + if (ar->attrs) + rta_free(ar->attrs); + ar->attrs = NULL; + ar->asr = NULL; + + /* Check if we can delete route */ + if (!EMPTY_LIST(ar->sum_membership)) + continue; + + /* Node can be safely deleted */ + fib_delete(&p->route_fib, ar); + } + + agg_withdraw_sumroute(p, asr); +} + +static void +agg_reconfig_sumroute(struct f_trie_node *tn, void *P) +{ + struct agg_proto *p = (struct agg_proto *)P; + struct agg_sumroute *asr_o, *asr = (struct agg_sumroute *)tn; + struct agg_route *ar; + struct agg_membership *ms; + struct cf_route *cr; + node *n, *n_next; + node *nn, *nn_next; + int found; + + if (!(asr->flags & AGG_FLAG_PREPARED)) + return; + + /* Find old corresponding route */ + asr_o = trie_match_longest_prefix(p->summary_trie, asr->tn.addr, asr->tn.plen); + + if ((!asr_o) || (!ipa_equal(asr_o->tn.addr, asr->tn.addr)) || (asr_o->tn.plen != asr->tn.plen)) + { + /* New summary route */ + agg_init_sumroute(p, asr); + return; + } + + ADBG("Reconfiguring summary route %I/%d", asr->tn.addr, asr->tn.plen); + + /* + * Old summary route exists. We need to: + * 1) remove DELETED flag + * 2) move every route to new list + * 3) compare mandatory routes + */ + + asr_o->flags &= ~AGG_FLAG_DELETED; + + /* + * Move usual routes to new list. + * Update ther pointer to summary route + */ + + WALK_LIST_DELSAFE(n, n_next, asr_o->routes) + { + ar = SKIP_BACK(struct agg_route, n_sumroute, n); + + ar->asr = asr; + add_tail(&asr->routes, &ar->n_sumroute); + } + + /* Mark old mandatory routes (instead of membership structurs) as deleted */ + WALK_LIST_DELSAFE(n, n_next, asr_o->mandatory_list) + { + ms = SKIP_BACK(struct agg_membership, n_sumroute, n); + ar = ms->ar; + ar->flags |= AGG_FLAG_DELETED; + } + + /* Walk all new mandatory routes */ + WALK_LIST_DELSAFE(n, n_next, asr->cf_routes) + { + cr = (struct cf_route *)n; + + /* In any case, we need to increase count of mandatory routes */ + asr->mandatory_total++; + + /* Check if prefix exists */ + ar = fib_find(&p->route_fib, &cr->px.addr, cr->px.len); + + if (!ar) + ar = agg_make_route(p, &cr->px.addr, cr->px.len); + + /* Increate current counter IFF we have real best rte associated with entry */ + if (ar->attrs) + { + asr->mandatory_current++; + ar->flags |= AGG_FLAG_INSTALLED; + } + + /* + * Check if we have summary membership with current asr (e.g. + * if we already are mandatory route for this asr). In this case + * we have to update asr pointer. + * + * No need to update summary route: + * no new routes are announced, mandatory route limit is not hit + */ + + found = 0; + WALK_LIST_DELSAFE(nn, nn_next, ar->sum_membership) + { + ms = SKIP_BACK(struct agg_membership, n_mandatory, nn); + if (ms->asr != asr_o) + continue; + + ADBG("Mandatory route %I/%d remains as is, removing deleted flag", ar->fn.prefix, ar->fn.pxlen); + /* Update pointers and relink */ + ms->asr = asr; + add_tail(&asr->mandatory_list, &ms->n_sumroute); + ar->flags &= ~AGG_FLAG_DELETED; + found = 1; + break; + } + + if (found) + continue; + + /* Add link to mandatory list of summary route */ + agg_link_mroute(p, asr, ar); + } + + /* Delete old mandatory routes */ + WALK_LIST_DELSAFE(n, n_next, asr_o->mandatory_list) + { + ms = SKIP_BACK(struct agg_membership, n_sumroute, n); + ar = ms->ar; + if (!(ar->flags & AGG_FLAG_DELETED)) + continue; + + /* + * This route is not mandatory for new asr. + * No need to update old configuration so + * we need to unlink node from ar and free it + */ + + agg_unlink_mroute(p, ms); + } + + /* XXX: we can possibly check new mandatory routes */ +} + +static int +agg_reconfigure(struct proto *P, struct proto_config *new) +{ + struct agg_config *o = (struct agg_config *)P->cf; + struct agg_config *n = (struct agg_config *)new; + struct agg_proto *p = (struct agg_proto *)P; + //struct agg_sumroute *; + + ADBG("Reconfiguting.."); + + /* Mark all old summary routes as deleted */ + trie_walk(o->summary_trie, agg_mark_sumroute, NULL); + + /* Walk new trie */ + trie_walk(n->summary_trie, agg_reconfig_sumroute, p); + + /* Cleanup all old summary routes */ + trie_walk(o->summary_trie, agg_clear_sumroute, p); + + /* Update trie pointer */ + p->summary_trie = n->summary_trie; + + return 1; +} + + +static void +agg_rt_notify(struct proto *P, rtable *src_table, net *n, rte *new, rte *old, ea_list *attrs) +{ + struct agg_proto *p = (struct agg_proto *) P; + struct agg_sumroute *asr; + struct agg_route *ar; + struct agg_membership *ms; + node *nn, *nn_next; + rta *old_rta = NULL; + + /* Ignore unreachable routes */ + if ((new) && (new->attrs->dest == RTD_UNREACHABLE)) + new = NULL; + + if ((old) && (old->attrs->dest == RTD_UNREACHABLE)) + old = NULL; + + if (!new && !old) + return; + + + //ADBG("RT event about %I/%d", n->n.prefix, n->n.pxlen); + /* + * Search trie to determine summary route. + * We use 1 bit less specific prefix to deal with the following 2 cases: + * 1) if announced X/Y prefix is the same as summary route this is clearly not the case for summarization + * 2) if nested summary routes are congigured and 1) is in action we got wrong asr pointer. + * + * We skip 0/0 and :: due to it can'be summarized + */ + if ((n->n.pxlen) && ((asr = trie_match_longest_prefix(p->summary_trie, n->n.prefix, n->n.pxlen - 1)))) + { + /* + * TODO: Find longest-match asr for found ar in new trie. + * If asr changes this means hieharchical summary is in action + */ + + ADBG("Found matched summary route %I/%d", asr->tn.addr, asr->tn.plen); + + /* Summary route found. Let's find/create route node */ + ar = agg_make_route(p, &n->n.prefix, n->n.pxlen); + + /* (new route, route update) */ + if (new) + { + old_rta = ar->attrs; + /* + * rte_update() guarantees rta to be cached. + * However, if import filter exists, attribute rta MAY be + * uncached or rta itself can be allocated from update linear pool. + * See f_run() and f_rta_cow() comments for more details + */ + + if (new->attrs->aflags & RTAF_CACHED) + ar->attrs = rta_clone(new->attrs); + else + { + /* Attributes are modified by filter, let's create stable storage. */ + ar->attrs = rta_clone(rta_lookup(new->attrs)); + } + + /* Add link to summary route if route is new */ + if (!ar->asr) + { + ar->asr = asr; + add_tail(&asr->routes, &ar->n_sumroute); + } + + /* Call route update */ + if (agg_can_announce(asr)) + agg_update_sumroute(p, asr, ar, old_rta, ar->attrs); + + /* Remove old rte */ + if (old_rta) + rta_free(old_rta); + } + else + { + /* route withdrawal */ + rem_node(&ar->n_sumroute); + + /* Take into account that create_sumroute() callback can be called from here */ + if (agg_can_announce(asr)) + agg_update_sumroute(p, asr, ar, ar->attrs, NULL); + + if (ar->attrs) + rta_free(ar->attrs); + ar->attrs = NULL; + ar->asr = NULL; + + /* INSTALLED flag is removed later */ + + if (EMPTY_LIST(ar->sum_membership)) + fib_delete(&p->route_fib, ar); + } + } + + /* Check if network is from our mandatory list */ + if ((ar = fib_find(&p->route_fib, &n->n.prefix, n->n.pxlen))) + { + ADBG("FIB record found for route %I/%d", n->n.prefix, n->n.pxlen); + /* Check if we need to change summary routes */ + if ((new && (!(ar->flags & AGG_FLAG_INSTALLED))) || (!new && (ar->flags & AGG_FLAG_INSTALLED))) + { + if (new) + ar->flags |= AGG_FLAG_INSTALLED; + else + ar->flags &= ~AGG_FLAG_INSTALLED; + + WALK_LIST_DELSAFE(nn, nn_next, ar->sum_membership) + { + ms = SKIP_BACK(struct agg_membership, n_mandatory, nn); + asr = ms->asr; + + ADBG("Found membership with summary route %I/%d", asr->tn.addr, asr->tn.plen); + + if (new) + { + asr->mandatory_current++; + /* Possible route announce */ + agg_announce_sumroute(p, asr); + } + else + { + /* Possible route withdrawal */ + if (agg_can_announce(asr)) + agg_withdraw_sumroute(p, asr); + asr->mandatory_current--; + } + } + } + } +} + + +static struct proto * +agg_init(struct proto_config *C) +{ + struct proto *P = proto_new(C, sizeof(struct agg_proto)); + + P->accept_ra_types = RA_OPTIMAL; + P->reload_routes = agg_reload_routes; + P->import_control = agg_import_control; + P->rt_notify = agg_rt_notify; + + return P; +} + +static int +agg_shutdown(struct proto *P) +{ + struct agg_proto *p = (struct agg_proto *)P; + + /* Mark all summary routes as deleted */ + trie_walk(p->summary_trie, agg_mark_sumroute, NULL); + + /* Cleanup all (now marked) summary routes */ + trie_walk(p->summary_trie, agg_clear_sumroute, p); + + return PS_DOWN; +} + +static void +agg_format_dest(struct rta *a, byte *via) +{ + switch (a->dest) + { + case RTD_ROUTER: bsprintf(via, "via %I on %s", a->gw, a->iface->name); break; + case RTD_DEVICE: bsprintf(via, "dev %s", a->iface->name); break; + case RTD_BLACKHOLE: bsprintf(via, "blackhole"); break; + case RTD_UNREACHABLE: bsprintf(via, "unreachable"); break; + case RTD_PROHIBIT: bsprintf(via, "prohibited"); break; + case RTD_MULTIPATH: bsprintf(via, "multipath"); break; + default: bsprintf(via, "???"); + } +} + +static void +agg_get_route_ainfo(struct cli *c, int cli_val, struct rte *e) +{ + struct agg_proto *p = (struct agg_proto *)e->attrs->proto; + node *n, *n_next; + struct rta *a; + struct agg_sumroute *asr; + struct agg_route *ar; + byte via[STD_ADDRESS_P_LENGTH+32], from[STD_ADDRESS_P_LENGTH+8]; + byte ia[STD_ADDRESS_P_LENGTH+8]; + + + if (!(asr = trie_match_longest_prefix(p->summary_trie, e->net->n.prefix, e->net->n.pxlen))) + return; + + WALK_LIST_DELSAFE(n, n_next, asr->routes) + { + ar = SKIP_BACK(struct agg_route, n_sumroute, n); + a = ar->attrs; + + bsprintf(ia, "%I/%d", ar->fn.prefix, ar->fn.pxlen); + agg_format_dest(a, via); + if (ipa_nonzero(a->from) && !ipa_equal(a->from, a->gw)) + bsprintf(from, " from %I", a->from); + else + from[0] = 0; + + cli_printf(c, cli_val, " + %-18s %s [%s%s]", ia, via, a->proto->name, from); + } +} + +struct protocol proto_agg = { + name: "ABGP", + template: "abgp%d", + preference: 0, + init: agg_init, + start: agg_start, + reconfigure: agg_reconfigure, + shutdown: agg_shutdown, + get_route_ainfo: agg_get_route_ainfo, +}; diff --git a/proto/agg/agg.h b/proto/agg/agg.h new file mode 100644 index 0000000..b20be86 --- /dev/null +++ b/proto/agg/agg.h @@ -0,0 +1,81 @@ +/* + * BIRD -- BGP route aggregation + * + * (c) 2012 Yandex LLC + * (c) 2012 Alexander V. Chernikov <melifaro@yandex-team.ru> + * + * Can be freely distributed and used under the terms of the GNU GPL. + */ + +#ifndef _BIRD_RT_AGG_H_ +#define _BIRD_RT_AGG_H_ + +struct agg_proto { + struct proto p; + struct f_trie *summary_trie; /* Trie with summary routes */ + struct fib route_fib; /* Fib with original/mandatory routes */ + struct linpool *lp; /* Linear pool used by aggregation functions */ +}; + +struct agg_config { + struct proto_config c; + struct f_trie *summary_trie; /* Trie for holding summary/mandatory route */ + list temp_list[BITS_PER_IP_ADDRESS]; /* Pre-sort lists */ +}; + +extern struct protocol proto_agg; + +/* route flags */ +#define AGG_FLAG_DELETED 0x0010 /* Summary/mandatory route is candidate for deletion */ +#define AGG_FLAG_MANDATORY 0x0020 /* Existance of this route is mandatory to advertise summary */ +#define AGG_FLAG_INSTALLED 0x0040 /* Route is installed */ +#define AGG_FLAG_NEW 0x0080 /* Newly allocated route */ + +/* Summary route flags */ +#define AGG_FLAG_PREPARED 0x0100 /* Entry is set up (ised in trie checking) */ +#define AGG_FLAG_SUMONLY 0x0200 /* Advertise summary route only */ +#define AGG_FLAG_MAXINFO 0x0400 /* Save as much info as possible */ + +/* Masks */ +#define AGG_FLAG_RMASK 0x00F0 /* Mask for route flags */ +#define AGG_FLAG_SUMMASK 0xFF00 /* Flags for summary rouutes */ + +/* Aggregated route information */ +struct agg_sumroute { + struct f_trie_node tn; /* Information about network */ + u16 route_src; /* Route source type (RTS_). XXX: Note field MUST not be zero */ + u16 flags; /* Aggregation flags */ + u16 mandatory_total; /* Number of mandatory routes */ + u16 mandatory_current; /* Number of currently advertised mandatory routes */ + struct rta *attrs; /* Aggregated route attributes */ + list routes; /* Networks summarized */ + list mandatory_list; /* List of mandatory2summary structures */ + list cf_routes; /* List of mandatory routes (used in config parsing) */ +}; + + +/* Route entry. Used by mandatory and "casual" routes */ +struct agg_route { + struct fib_node fn; /* Network node (both) */ + u16 flags; /* Route flafs (both) */ + struct agg_sumroute *asr; /* Pointer to summary route (casual) */ + struct rta *attrs; /* Attributes of best current rte (casual) */ + list sum_membership; /* List with mandatory route membership info (mandatory) */ + node n_sumroute; /* Per-sumroute list node (casual) */ +}; + +/* Mandatory route */ +struct cf_route { + node n; /* Node from cf_entries */ + struct prefix px; /* Prefix */ +}; + +/* Mandatory-2-Summary membership */ +struct agg_membership { + struct agg_sumroute *asr; /* Pointer to summary route */ + struct agg_route *ar; /* Pointer to mandatory route */ + node n_mandatory; /* agg_mandatory node */ + node n_sumroute; /* agg_summary node */ +}; + +#endif diff --git a/proto/agg/config.Y b/proto/agg/config.Y new file mode 100644 index 0000000..1d7fdb0 --- /dev/null +++ b/proto/agg/config.Y @@ -0,0 +1,99 @@ +/* + * BIRD -- BGP route aggregation + * + * (c) 2012 Yandex LLC + * (c) 2012 Alexander V. Chernikov <melifaro@yandex-team.ru> + * + * Can be freely distributed and used under the terms of the GNU GPL. + */ + +CF_HDR + +#include "proto/agg/agg.h" + +CF_DEFINES + +#define LOCAL_DEBUG +#define AGG_CFG ((struct agg_config *) this_proto) +int current_rtype = 0; +struct agg_sumroute *asr; + +CF_DECLS + +CF_KEYWORDS(AGGREGATOR, AGGREGATE, ADDRESS, SUMMARY, ONLY, SAVE, ATTRIBUTES, MANDATORY, LIST, BGP, OSPF, E1, E2) + +%type <i> agg_route_type +CF_GRAMMAR + +CF_ADDTO(proto, agg_proto '}') + +agg_proto_start: proto_start AGGREGATOR { + this_proto = proto_config_new(&proto_agg, sizeof(struct agg_config), $1); + AGG_CFG->summary_trie = f_new_trie(cfg_mem, sizeof(struct agg_sumroute)); + } + ; + +agg_proto: + agg_proto_start proto_name '{' + | agg_proto agg_proto_item ';' + ; + +agg_proto_item: + proto_item + | agg_sum_routes + ; + +agg_sum_routes: + agg_route_type '{' agg_routes_entries '}' + ; + +agg_routes_entries: + agg_route_entry ';' + | agg_routes_entries agg_route_entry ';' + ; + +agg_route_entry: + AGGREGATE ADDRESS prefix { + asr = (struct agg_sumroute *)trie_add_prefix(AGG_CFG->summary_trie, $3.addr, $3.len, $3.len + 1, MAX_PREFIX_LENGTH); + if (asr->flags & AGG_FLAG_PREPARED) + cf_error("Prefix %I/%d already exists", $3.addr, $3.len); + + asr->route_src = current_rtype; + init_list(&asr->routes); + init_list(&asr->mandatory_list); + init_list(&asr->cf_routes); + asr->flags = AGG_FLAG_PREPARED; + } agg_options + ; + +agg_options: + SUMMARY ONLY { asr->flags |= AGG_FLAG_SUMONLY; } + | SAVE ATTRIBUTES { asr->flags |= AGG_FLAG_MAXINFO; } + | MANDATORY LIST '{' agg_option_mlist '}' + | + ; + +agg_option_mlist: + agg_option_mlist_entry + | agg_option_mlist ',' agg_option_mlist_entry + ; + +agg_option_mlist_entry: + prefix { + /* Simply add to cf_routes */ + struct cf_route *mr = cfg_allocz(sizeof(struct cf_route)); + mr->px = $1; + add_tail(&asr->cf_routes, &mr->n); + } + ; + +agg_route_type: + BGP { current_rtype = RTS_BGP; } + | OSPF E1 { current_rtype = RTS_OSPF_EXT1; } + | OSPF E2 { current_rtype = RTS_OSPF_EXT2; } + ; + + +CF_CODE + +CF_END diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c index 4495c03..180ccbf 100644 --- a/proto/bgp/attrs.c +++ b/proto/bgp/attrs.c @@ -19,9 +19,14 @@ #include "lib/resource.h" #include "lib/string.h" #include "lib/unaligned.h" +#ifdef CONFIG_AGG +#include "filter/filter.h" +#include "proto/agg/agg.h" +#endif #include "bgp.h" +#define BDBG(msg, ...) log("%s:%d " msg, __FUNCTION__, __LINE__, ##__VA_ARGS__) /* * UPDATE message error handling * @@ -1516,6 +1521,755 @@ bgp_remove_as4_attrs(struct bgp_proto *p, rta *a) } } +#define BGP_AS_MAX_NUMBER 256 +#define BGP_AS_MAX_LEN 1024 /* 256 4-byte ASNs (maximum tuple size) */ +#define BGP_AS_MAX_PTRS 64 /* 64 tuples max */ +/* + * bgp_append_as_tuple - add item to sorted array of fixed size + * @number: item + * @pbuf: pointer to start of array + * @count: pointer to current iterms count + * + * Returns: 1 if item is added (@count is incremented) + * 0 if item already exists + * -1 if array size is exceeded + */ +static int +bgp_sorted_add_as4(u32 number, u32 *pbuf, byte *count) +{ + int min, max, mid, shift; + + if (*count == 0) + { + *count = (*count) + 1; + *pbuf = number; + return 1; + } + + /* Binary search */ + min = 0; + max = *count - 1; + mid = 0; + while (min <= max) + { + mid = (min + max) / 2; + if (pbuf[mid] == number) + return 0; + + if (pbuf[mid] > number) + max = mid - 1; + else + min = mid + 1; + } + + /* Not found. */ + if (*count == BGP_AS_MAX_NUMBER - 1) + return -1; + + if (pbuf[mid] < number) + shift = mid + 1; + else + shift = mid; + + if (*count > shift) + memmove(pbuf + shift + 1, pbuf + shift, (*count - shift) * sizeof(u32)); + pbuf[shift] = number; + *count = *count + 1; + + return 1; +} + +/* + * bgp_append_as_tuple - append ASNs from one or more AS_SEQ/AS_SET tuples to an array + * @src_buf: buffer with chain of AS_SEQUNCE or AS_SET tuples + * @src_len: buffer length + * @as_set_ptrs: pointer to array of pointers to sorted u32 arrays of ASNs + * @as_set_len: pointer to array of length of given arrays + * @as_set_index: current array index + * @lp: linear pool to allocate data from + */ +static void +bgp_append_as_tuple(byte *src_buf, int src_len, byte **as_set_ptrs, byte *as_set_length, int *as_set_index, struct linpool *lp) +{ + u32 asn; + int asn_count, i = *as_set_index; + u32 *set_ptr; + byte *cnt_ptr; + + set_ptr = (u32 *)as_set_ptrs[i]; + cnt_ptr = &as_set_length[i]; + + while (src_len) + { + asn_count = src_buf[1]; + src_len -= 2 + 4 * asn_count; + src_buf += 2; + while (asn_count) + { + asn = get_u32(src_buf); + + /* Append number to array */ + if (bgp_sorted_add_as4(asn, set_ptr, cnt_ptr) == -1) + { + /* This tuple is full, let's advance to the next */ + + /* We have to leave room for other BGP data */ + if (i == BGP_AS_MAX_PTRS - 2) + return; + + *as_set_index = ++i; + as_set_ptrs[i] = lp_alloc(lp, BGP_AS_MAX_LEN); + set_ptr = (u32 *)as_set_ptrs[i]; + cnt_ptr = &as_set_length[i]; + + BDBG("Index increased to %d", i); + + /* Add to empty array */ + bgp_sorted_add_as4(asn, set_ptr, cnt_ptr); + } + + //BDBG("Index: %d asn_count: %d cnt: %d curr_asn=%u", i, asn_count, *cnt_ptr, asn); + + src_buf += 4; + asn_count--; + } + } +} + +/* + * bgp_compile_sum_aspath - make adata attribute for AS_PATH + * @as_data_ptr: pointer to common data for all routes + * @as_len: common data length + * @as_set_ptrs: pointer to array of pointers to sorted u32 arrays of ASNs + * @as_set_len: pointer to array of length of given arrays + * @as_set_index: current array index + * @lp: linear pool to allocate data from + * + * Function gets 'common' data (possibly consisting of one or more AS_SEQUNCE / AS_SET tuples) and + * several arrays with sorted list of ASNs. Each array is converted to AS_SET tuple, All these AS_SET + * tuples are added to the end of 'common' data. + * + */ +static struct adata * +bgp_compile_sum_aspath(byte *as_data_ptr, int as_len, byte **as_set_ptrs, byte *as_set_len, int *as_set_index, struct linpool *lp) +{ + int i, j, len = 0; + u32 *asn; + byte *q; + struct adata *a; + + for (i = 0; i <= *as_set_index; i++) + { + if (as_set_len[i]) + len += 2 + 4 * as_set_len[i]; + } + + //BDBG("bgp_compile_sum_aspath(): Len=%d as_len=%d", len, as_len); + + /* Merge both paths to contiguous storage */ + a = bgp_alloc_adata(lp, len + as_len); + q = a->data; + /* Copy 'common' part */ + memcpy(q, as_data_ptr, as_len); + + if (!len) + return a; + + q += as_len; + /* For each array, write AS_SET header and data */ + for (i = 0; i <= *as_set_index; i++) + { + *q++ = AS_PATH_SET; + *q++ = as_set_len[i]; + asn = (u32 *)as_set_ptrs[i]; + for (j = 0; j < as_set_len[i]; j++, q += sizeof(u32)) + put_u32(q, *asn++); + } + + return a; +} + +/* + * bgp_sum_origin - update summary ORIGIN attribute + * @attrs: pointer to new route attributes + * @origin: pointer to current ORIGIN value + */ +inline void +bgp_sum_origin(rta *attrs, int *origin) +{ + struct eattr *ea; + int new_origin; + + if (ea = ea_find(attrs->eattrs, EA_CODE(EAP_BGP, BA_ORIGIN))) + new_origin = ea->u.data; + else + { + switch (attrs->source) + { + case RTS_OSPF: + case RTS_OSPF_IA: + case RTS_OSPF_EXT1: + case RTS_OSPF_EXT2: + new_origin = ORIGIN_IGP; + break; + + default: + new_origin = ORIGIN_INCOMPLETE; + } + } + + if (new_origin == ORIGIN_INCOMPLETE) + *origin = ORIGIN_INCOMPLETE; + else if ((new_origin == ORIGIN_EGP) && (*origin == ORIGIN_IGP)) + *origin = ORIGIN_EGP; +} + +/* + * bgp_sum_aspath - update summary AS_PATH attribute + * @ea: new AS_PATH attribuye + * @as_differs: are we already in 'differ' mode + * @as_data_ptr: pointer to common data for all routes + * @as_len: common data length + * @as_set_ptrs: pointer to array of pointers to sorted u32 arrays of ASNs + * @as_set_len: pointer to array of length of given arrays + * @as_set_index: current array index + * @lp: linear pool to allocate data from + */ +void +bgp_sum_aspath(eattr *ea, int *as_differs, byte *as_data_ptr, int *as_len, byte **as_set_ptrs, byte *as_set_len, int *as_set_index, struct linpool *lp) +{ + int new_len, mlen, slen; + byte *sum_off, *new_off, *new_ptr; + + new_len = ea->u.ptr->length; + new_ptr = ea->u.ptr->data; + + /* Check if new AS_PATH is the same */ + if ((*as_differs == 0) && (*as_len == new_len) && (memcmp(as_data_ptr, new_ptr, new_len) == 0)) + return; + + /* + * New AS_PATH differs. We use easy and naive implementation + * from RFC4271 9.2.2.2: + * 1) Find as much as possible AS_SEQ / AS_SET segments at the + * beginning (usually zero) + * 2) put the rest into huge sorted AS_SET (or several AS_SETs) + */ + *as_differs = 1; + + /* + * Compare AS_SET / AS_SEQ tuples one by one. + * We assume both SETs to be validated + */ + + mlen = MIN(*as_len, new_len); + sum_off = as_data_ptr; + new_off = new_ptr; + + while (mlen > 0) + { + /* Check if segment type and length is the same */ + if (memcmp(sum_off, new_off, 2)) + break; + + slen = 2 + 4 * new_off[1]; + if (memcmp(sum_off, new_off, slen)) + break; + + /* Segment is the same, moving to the next */ + sum_off += slen; + new_off += slen; + mlen -= slen; + } + + //BDBG("MIN=%d mlen=%d", MIN(*as_len, new_len), mlen); + + /* + * 1) If xlen is > 0 we need to put to AS_SET buffer ALL different tuples from sum_off and new_off. + * 2) If xlen is zero but new_len is larger, we need to put to AS_SET buffer tuples from new_off + * 3) If xlen is zero but sum_len is larger, we need to put to AS_SET buffer tuples from sum_off + */ + if (sum_off != as_data_ptr + *as_len) + { + BDBG("Move ASNs from summary to AS-SET, length=%d", as_data_ptr + *as_len - sum_off); + bgp_append_as_tuple(sum_off, as_data_ptr + *as_len - sum_off, as_set_ptrs, as_set_len, as_set_index, lp); + *as_len = sum_off - as_data_ptr; + } + + if (new_off != new_ptr + new_len) + { + BDBG("Move ASNs from new to AS-SET, length=%d", new_ptr + new_len - new_off); + bgp_append_as_tuple(new_off, new_ptr + new_len - new_off, as_set_ptrs, as_set_len, as_set_index, lp); + } +} + +/* + * bgp_update_sum_rte - create and announce updated summary rte + * @p: pointer to protocol instance + * @asr: pointer to summary route + * @origin: value of ORIGIN attribute + * @as_part: pointer to AS_PATH attribute data + * @atomic_agg: value of ATOMIC_AGGREGATE attribute + * @aggregator: pointer to AGGREGATOR attribute value + * + * Function creates stable rta (via rta_clone) and announces it + */ +static void +bgp_update_sum_rte(struct agg_proto *p, struct agg_sumroute *asr, int origin, struct adata *as_path, int atomic_agg, struct adata *aggregator) +{ + int i, slen; + struct ea_list *eal; + rta a, *attrs; + rte *route; + struct adata *atomic_ad; + + slen = atomic_agg ? 4 : 3; + eal = lp_allocz(p->lp, sizeof(struct ea_list) + sizeof(eattr) * slen); + eal->flags = EALF_SORTED; + eal->count = slen; + + i = 0; + + /* ORIGIN */ + bgp_set_attr(&eal->attrs[i++], BA_ORIGIN, origin); + + /* AS_PATH */ + bgp_set_attr(&eal->attrs[i++], BA_AS_PATH, (uintptr_t)as_path); + + /* ATOMIC_AGGREGATE */ + if (atomic_agg) + { + atomic_ad = bgp_alloc_adata(p->lp, 0); + bgp_set_attr(&eal->attrs[i++], BA_ATOMIC_AGGR, (uintptr_t)atomic_ad); + } + + /* AGGREGATOR */ + bgp_set_attr(&eal->attrs[i++], BA_AGGREGATOR, (uintptr_t)aggregator); + + /* Fill in temporary rta */ + bzero(&a, sizeof(a)); + a.proto = &p->p; + a.source = RTS_BGP; + a.scope = SCOPE_UNIVERSE; + a.cast = RTC_UNICAST; + a.dest = RTD_BLACKHOLE; +/* + a.gw = r->via; + a.iface = NULL; +*/ + a.eattrs = eal; + + attrs = rta_lookup(&a); + + route = rte_get_temp(attrs); + + /* Save copy of attributes */ + attrs = rta_clone(attrs); + + route->net = net_get(p->p.table, asr->tn.addr, asr->tn.plen); + route->pflags = 0; + + /* Update summary route */ + rte_update(p->p.table, route->net, &p->p, &p->p, route); + + /* Free old attrs if any */ + if (asr->attrs) + rta_free(asr->attrs); + /* Save copy of attributes */ + asr->attrs = attrs; +} + + +void +bgp_create_sumroute(struct agg_proto *p, struct agg_sumroute *asr) +{ + int as_set = 0, as_len = 0, new_len; + struct agg_route *ar; + struct eattr *ea; + struct rta *attrs; + node *n, *n_next; + int origin = ORIGIN_IGP, atomic_agg = 0; + u32 agg_as = 0, agg_id = 0, asn_set = 0; + byte *new_ptr; + int as_differs = 0; + int as_set_index = 0; + int agg_skip = 1; + struct bgp_proto *bgp_p; + byte *as_data_ptr = NULL; + struct adata *ad, *as_path; + byte *as_set_ptrs[BGP_AS_MAX_PTRS], as_set_len[BGP_AS_MAX_PTRS]; + + BDBG("bgp_create_sumroute() called for %I/%d", asr->tn.addr, asr->tn.plen); + + /* + * Do route aggregation per RFC4271 9.2.2.2 rules + * + * [0] NEXT_HOP (4 or 16 or 2x16) + * [1] ORIGIN (internal, u32) + * [2] AS_PATH (variable) + * [3] AGGREGATOR (8 bytes) + * [4] ATOMIC_AGGREGATE (opt, 6 bytes) + * + */ + /* Zero set length */ + memset(&as_set_len, 0, sizeof(as_set_len)); + as_set_ptrs[0] = lp_alloc(p->lp, BGP_AS_MAX_LEN); + + WALK_LIST_DELSAFE(n, n_next, asr->routes) + { + ar = SKIP_BACK(struct agg_route, n_sumroute, n); + + attrs = ar->attrs; + BDBG("Working on route %I/%d source=%d", ar->fn.prefix, ar->fn.pxlen, attrs->source); + + /* + * FIXME: Routes with different MED should not be aggregated. + * However this is another non-deterministic place + */ + /* Save ASN & BGP router id from first BGP route */ + if (attrs->source == RTS_BGP) + { + bgp_p = (struct bgp_proto *)attrs->proto; + if (!asn_set) + { + /* Save data */ + agg_as = bgp_p->local_as; + agg_id = bgp_p->local_id; + BDBG("Summary route ASN/ID set to %d/%R", agg_as, agg_id); + asn_set = 1; + agg_skip = 0; + } + else + { + if ((agg_as != bgp_p->local_as) || (agg_id != bgp_p->local_id)) + { + log(L_ERR "%s: Cannot aggregate route %I/%d into %I/%d, skipping", + asr->tn.addr, asr->tn.plen, ar->fn.prefix, ar->fn.pxlen); + agg_skip = 1; + } + } + } + + /* + * Check AS_PATH. AS_PATH is normalized to 4b ASNs in bgp_decode_attr(). + * We assume all AS_PATH attributes BGP routes are encoded in 4b format + */ + if (ea = ea_find(attrs->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH))) + { + /* BGP route */ + new_len = ea->u.ptr->length; + new_ptr = ea->u.ptr->data; + } + else + { + /* Non-BGP route, let's set empty attribute */ + new_len = 0; + new_ptr = NULL; + } + + if (asr->flags & AGG_FLAG_MAXINFO) + { + if (!as_set) + { + as_len = new_len; + as_data_ptr = lp_alloc(p->lp, as_len ? as_len : 4); + memcpy(as_data_ptr, new_ptr, as_len); + as_set = 1; + } + else if (new_ptr) + bgp_sum_aspath(ea, &as_differs, as_data_ptr, &as_len, as_set_ptrs, as_set_len, &as_set_index, p->lp); + } + + /* Check ORIGIN () */ + bgp_sum_origin(attrs, &origin); + + /* Check ATOMIC_AGGREGATE */ + if (ea = ea_find(attrs->eattrs, EA_CODE(EAP_BGP, BA_ATOMIC_AGGR))) + atomic_agg = 1; + } + + /* Skip route? */ + if (agg_skip) + { + log(L_ERR "%s: Route %I/%d cannot be sumarized due to nonexisting/conflicting Router Id/ASN", asr->tn.addr, asr->tn.plen); + return; + } + + /* + * Make out list sorted by default + * + * [0] ORIGIN (V=1) (internal, u32) + * [1] AS_PATH (V=2) (variable) + * [2] ATOMIC_AGGREGATE (V=6) (opt, zero) + * [3] AGGREGATOR (V=7) (8 bytes) + * + */ + + /* Prepare AS_PATH */ + as_path = bgp_compile_sum_aspath(as_data_ptr, as_len, as_set_ptrs, as_set_len, &as_set_index, p->lp); + + /* Prepare AGGREGATOR */ + ad = bgp_alloc_adata(p->lp, 8); + new_ptr = ad->data; + put_u32(new_ptr, agg_as); + put_u32(new_ptr + 4, agg_id); + + /* Create stable attributes with rte */ + bgp_update_sum_rte(p, asr, origin, as_path, atomic_agg, ad); + + lp_flush(p->lp); +} + + +#define DBG_UPD(x) BDBG("Summary route update requires reannounce due to changed " x " attribute") +void +bgp_update_sumroute(struct agg_proto *p, struct agg_sumroute *asr, struct agg_route *ar, struct rta *old, struct rta *new) +{ + struct eattr *ea, *ea_new; + rta *a; + int origin = ORIGIN_IGP, atomic_agg = 0, rebuild = 0; + struct adata *as_path, *aggregator; + node *n, *n_next; + + BDBG("bgp_update_sumroute: route %I/%d , summary %I/%d", ar->fn.prefix, ar->fn.pxlen, asr->tn.addr, asr->tn.plen); + + if (!(a = asr->attrs)) + { + if (!new) + return; + + bgp_create_sumroute(p, asr); + return; + } + + /* + * [0] ORIGIN (V=1) (internal, u32) + * [1] AS_PATH (V=2) (variable) + * [3] ATOMIC_AGGREGATE (V=6) (opt, zero) + * [4] AGGREGATOR (V=7) (8 bytes) + * + */ + if (!new) + { + + /* route witdrawal */ + /* Check if we can skip rebuilding */ + BDBG("Widrawing route %I/%d from summary %I/%d", ar->fn.prefix, ar->fn.pxlen, asr->tn.addr, asr->tn.plen); + + /* + * AS_PATH + * If MAXINFO flag is not set we don't care (AS_PATH is empty) + * if MAXINFO is set but attribute length is zero we don't care, too + * Overwise, full rebuild is requires + */ + if ((asr->flags & AGG_FLAG_MAXINFO) && (ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH)))) + { + if (ea->u.ptr->length > 0) + { + /* We have to save every AS in AS_PATH and it is not empty. */ + DBG_UPD("AS_PATH"); + bgp_create_sumroute(p, asr); + return; + } + } + + /* Summary AS_PATH is not changed */ + + /* + * ORIGIN + * In most cases we got INCOMPLETE in both summary route and witdrawn attribute, + * so we simply cycle thru all more specific routes to determine new origin attribute + * + * ATOMIC_AGGREGATE + * Check for its new value, too + */ + + WALK_LIST_DELSAFE(n, n_next, asr->routes) + { + ar = SKIP_BACK(struct agg_route, n_sumroute, n); + + BDBG("Working on route %I/%d", ar->fn.prefix, ar->fn.pxlen); + bgp_sum_origin(ar->attrs, &origin); + + if (ea = ea_find(ar->attrs->eattrs, EA_CODE(EAP_BGP, BA_ATOMIC_AGGR))) + atomic_agg = 1; + } + + if (ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_ORIGIN))) + { + if ((ea->u.data != origin)) + { + DBG_UPD("ORIGIN"); + rebuild = 1; + } + } + + if (ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_ATOMIC_AGGR))) + { + if ((ea->u.data != atomic_agg)) + { + DBG_UPD("ATOMIC_AGG"); + rebuild = 1; + } + } + + if (!rebuild) + { + BDBG("Withdrawal of route %I/%d does not require summary route to be updated", ar->fn.prefix, ar->fn.pxlen); + return; + } + + BDBG("Withdrawal of route %I/%d require summary route to be updated", ar->fn.prefix, ar->fn.pxlen); + + /* + * We don't need full update here since we already know all summarized attributes data: + * AS_PATH is empty + * ORIGIN / ATOMIC_AGGREGATE values are known + * AGGREGATOR value cannot change (so we import it from current summary route) + */ + + /* Create empty AS_PATH */ + as_path = bgp_alloc_adata(p->lp, 0); + + /* Create AGGREGATOR attribute */ + aggregator = bgp_alloc_adata(p->lp, 8); + + if (ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AGGREGATOR))) + memcpy(aggregator + 1, ea->u.ptr->data, 8); + + bgp_update_sum_rte(p, asr, origin, as_path, atomic_agg, aggregator); + lp_flush(p->lp); + return; + } + + /************************************************ + * New route or route update. * + ************************************************/ + /* Check ORIGIN */ + if (ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_ORIGIN))) + { + origin = ea->u.data; + bgp_sum_origin(new, &origin); + if (origin != ea->u.data) + { + DBG_UPD("ORIGIN"); + rebuild = 1; + } + } + + /* Check AS_PATH */ + ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH)); + + byte *as_set_ptrs[BGP_AS_MAX_PTRS], as_set_len[BGP_AS_MAX_PTRS]; + int as_differs, as_len, as_set_index; + byte *as_data_ptr; + + /* + * Check if new route: + * 1) is BGP route (contains AS_PATH) + * 2) New AS_PATH is not empty + * 3) New AS_PATH is different + */ + as_path = NULL; + + if ((asr->flags & AGG_FLAG_MAXINFO) && (ea_new = ea_find(new->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH))) && (ea_new->u.ptr->length)) + { + if ((ea->u.ptr->length != ea_new->u.ptr->length) || (memcmp(ea->u.ptr->data, ea_new->u.ptr->data, ea_new->u.ptr->length))) + { + /* AS_PATH differs */ + as_len = ea->u.ptr->length; + as_data_ptr = lp_alloc(p->lp, as_len ? as_len : 4); + memcpy(as_data_ptr, ea->u.ptr->data, as_len); + + as_differs = 1; + memset(&as_set_len, 0, sizeof(as_set_len)); + as_set_ptrs[0] = lp_alloc(p->lp, BGP_AS_MAX_LEN); + as_set_index = 0; + + bgp_sum_aspath(ea_new, &as_differs, as_data_ptr, &as_len, as_set_ptrs, as_set_len, &as_set_index, p->lp); + as_path = bgp_compile_sum_aspath(as_data_ptr, as_len, as_set_ptrs, as_set_len, &as_set_index, p->lp); + + DBG_UPD("AS_PATH"); + rebuild = 1; + } + } + + /* Check ATOMIC_AGGREGATE */ + if (ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_ATOMIC_AGGR))) + atomic_agg = 1; + + if ((ea_find(new->eattrs, EA_CODE(EAP_BGP, BA_ATOMIC_AGGR))) && (!atomic_agg)) + { + DBG_UPD("ATOMIC_AGGREGATE"); + atomic_agg = 1; + rebuild = 1; + } + + /* Check ORIGIN */ + if (ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_ORIGIN))) + { + origin = ea->u.data; + bgp_sum_origin(new, &origin); + if (origin != ea->u.data) + { + DBG_UPD("ORIGIN"); + rebuild = 1; + } + } + + /* Check AGGREGATOR */ + struct bgp_proto *bgp_p = NULL; + byte agg[8]; + if (new->source == RTS_BGP) + { + bgp_p = (struct bgp_proto *)new->proto; + put_u32(agg, bgp_p->local_as); + put_u32(agg + 4, bgp_p->local_id); + ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AGGREGATOR)); + if (memcmp(agg, ea->u.ptr->data, 8)) + { + BDBG("New route %I/%d %d/%R ASN/BGP ID differs from summary route (%d/%R). Ignoring", + ar->fn.prefix, ar->fn.pxlen, bgp_p->local_as, bgp_p->local_id, + get_u32(ea->u.ptr->data), get_u32(ea->u.ptr->data + 4)); + if (rebuild) + lp_flush(p->lp); + return; + } + } + + if (!rebuild) + { + BDBG("New route %I/%d does not require summary route to be updated", ar->fn.prefix, ar->fn.pxlen); + return; + } + + DBG("New route %I/%d require summary route to be updated", ar->fn.prefix, ar->fn.pxlen); + + /* Copy current AS_PATH if not set */ + if (!as_path) + { + ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AS_PATH)); + as_len = ea->u.ptr->length; + as_path = bgp_alloc_adata(p->lp, as_len); + memcpy(as_path->data, ea->u.ptr->data, as_len); + } + + /* Copy AGGREGATOR attribute */ + aggregator = bgp_alloc_adata(p->lp, 8); + + if (bgp_p) + memcpy(aggregator + 1, agg, 8); + else + { + if (ea = ea_find(a->eattrs, EA_CODE(EAP_BGP, BA_AGGREGATOR))) + memcpy(aggregator + 1, ea->u.ptr->data, 8); + } + + bgp_update_sum_rte(p, asr, origin, as_path, atomic_agg, aggregator); + lp_flush(p->lp); +} +#undef BGP_UPD + /** * bgp_decode_attrs - check and decode BGP attributes * @conn: connection diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c index 4d3c32f..b23e21a 100644 --- a/proto/bgp/bgp.c +++ b/proto/bgp/bgp.c @@ -1174,6 +1174,7 @@ bgp_show_proto_info(struct proto *P) } } + struct protocol proto_bgp = { name: "BGP", template: "bgp%d", @@ -1188,5 +1189,9 @@ struct protocol proto_bgp = { get_status: bgp_get_status, get_attr: bgp_get_attr, get_route_info: bgp_get_route_info, - show_proto_info: bgp_show_proto_info + show_proto_info: bgp_show_proto_info, +#ifdef CONFIG_AGG + create_sumroute: bgp_create_sumroute, + update_sumroute: bgp_update_sumroute +#endif }; diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h index a8c5818..21ace7b 100644 --- a/proto/bgp/bgp.h +++ b/proto/bgp/bgp.h @@ -184,6 +184,8 @@ static inline void set_next_hop(byte *b, ip_addr addr) { ((ip_addr *) b)[0] = ad void bgp_attach_attr(struct ea_list **to, struct linpool *pool, unsigned attr, uintptr_t val); byte *bgp_attach_attr_wa(struct ea_list **to, struct linpool *pool, unsigned attr, unsigned len); +void bgp_create_sumroute(struct agg_proto *p, struct agg_sumroute *asr); +void bgp_update_sumroute(struct agg_proto *p, struct agg_sumroute *asr, struct agg_route *ar, struct rta *old, struct rta *new); struct rta *bgp_decode_attrs(struct bgp_conn *conn, byte *a, unsigned int len, struct linpool *pool, int mandatory); int bgp_get_attr(struct eattr *e, byte *buf, int buflen); int bgp_rte_better(struct rte *, struct rte *); diff --git a/sysdep/autoconf.h.in b/sysdep/autoconf.h.in index d029e2a..d10b409 100644 --- a/sysdep/autoconf.h.in +++ b/sysdep/autoconf.h.in @@ -42,6 +42,7 @@ #undef CONFIG_BGP #undef CONFIG_OSPF #undef CONFIG_PIPE +#undef CONFIG_AGG /* We have <syslog.h> and syslog() */ #undef HAVE_SYSLOG -- 1.7.3.2 --------------000303020204090509040505--