October 2023 - Bird-users

[PATCH] Babel: allow enabling link quality estimation manually
by Nick Cao 09 Apr '25

09 Apr '25

Link quality estimation is useful for link types other than wireless, especially when using babel with tunnels where packet losses do occur. --- doc/bird.sgml | 6 ++++++ proto/babel/babel.c | 19 ++++++------------- proto/babel/babel.h | 1 + proto/babel/config.Y | 5 ++++- 4 files changed, 17 insertions(+), 14 deletions(-) diff --git a/doc/bird.sgml b/doc/bird.sgml index 8041faa9..417ec030 100644 --- a/doc/bird.sgml +++ b/doc/bird.sgml @@ -2032,6 +2032,12 @@ protocol babel [<name>] { hardware drivers or platforms do not implement this feature. Default: yes. + <tag><label id="babel-link-quality">link quality <m/switch/</tag> + If set, link quality estimation is performed on this interface. + Link quality is measured by packet loss and is used for computing + metrics of routes going through this interface. Default: yes for + wireless interfaces, otherwise no. + <tag><label id="babel-next-hop-ipv4">next hop ipv4 <m/address/</tag> Set the next hop address advertised for IPv4 routes advertised on this interface. Default: the preferred IPv4 address of the interface. diff --git a/proto/babel/babel.c b/proto/babel/babel.c index 7f0cca73..6a238d75 100644 --- a/proto/babel/babel.c +++ b/proto/babel/babel.c @@ -593,21 +593,15 @@ babel_update_cost(struct babel_neighbor *nbr) if (!rcv || !nbr->ifa->up) goto done; - switch (cf->type) - { - case BABEL_IFACE_TYPE_WIRED: - case BABEL_IFACE_TYPE_TUNNEL: + if (!cf->link_quality) { /* k-out-of-j selection - Appendix 2.1 in the RFC. */ /* Link is bad if less than cf->limit/16 of expected hellos were received */ - if (rcv * 16 < cf->limit * max) - break; - - rxcost = cf->rxcost; - txcost = nbr->txcost; - break; - - case BABEL_IFACE_TYPE_WIRELESS: + if (!(rcv * 16 < cf->limit * max)) { + rxcost = cf->rxcost; + txcost = nbr->txcost; + } + } else { /* * ETX - Appendix 2.2 in the RFC. * @@ -622,7 +616,6 @@ babel_update_cost(struct babel_neighbor *nbr) */ rxcost = MIN( cf->rxcost * max / rcv, BABEL_INFINITY); txcost = MIN(nbr->txcost * max / rcv, BABEL_INFINITY); - break; } if (cf->rtt_cost && nbr->srtt > cf->rtt_min) diff --git a/proto/babel/babel.h b/proto/babel/babel.h index edde4cab..d152d099 100644 --- a/proto/babel/babel.h +++ b/proto/babel/babel.h @@ -145,6 +145,7 @@ struct babel_iface_config { u8 type; u8 limit; /* Minimum number of Hellos to keep link up */ u8 check_link; + u8 link_quality; uint port; uint hello_interval; /* Hello interval, in us */ uint ihu_interval; /* IHU interval, in us */ diff --git a/proto/babel/config.Y b/proto/babel/config.Y index b8af0267..cbf873c5 100644 --- a/proto/babel/config.Y +++ b/proto/babel/config.Y @@ -26,7 +26,7 @@ CF_KEYWORDS(BABEL, INTERFACE, METRIC, RXCOST, HELLO, UPDATE, INTERVAL, PORT, TYPE, WIRED, WIRELESS, RX, TX, BUFFER, PRIORITY, LENGTH, CHECK, LINK, NEXT, HOP, IPV4, IPV6, BABEL_METRIC, SHOW, INTERFACES, NEIGHBORS, ENTRIES, RANDOMIZE, ROUTER, ID, AUTHENTICATION, NONE, MAC, PERMISSIVE, - EXTENDED, TUNNEL, RTT, MIN, MAX, DECAY, SEND, TIMESTAMPS) + EXTENDED, TUNNEL, RTT, MIN, MAX, DECAY, SEND, TIMESTAMPS, QUALITY) CF_GRAMMAR @@ -72,6 +72,7 @@ babel_iface_start: BABEL_IFACE->rtt_decay = BABEL_RTT_DECAY; BABEL_IFACE->rtt_send = 1; BABEL_IFACE->check_link = 1; + BABEL_IFACE->link_quality = 0; BABEL_IFACE->ext_next_hop = 1; }; @@ -84,6 +85,7 @@ babel_iface_finish: BABEL_IFACE->hello_interval = BABEL_HELLO_INTERVAL_WIRELESS; if (!BABEL_IFACE->rxcost) BABEL_IFACE->rxcost = BABEL_RXCOST_WIRELESS; + BABEL_IFACE->link_quality = 1; } else { @@ -156,6 +158,7 @@ babel_iface_item: | TX tos { BABEL_IFACE->tx_tos = $2; } | TX PRIORITY expr { BABEL_IFACE->tx_priority = $3; } | CHECK LINK bool { BABEL_IFACE->check_link = $3; } + | LINK QUALITY bool { BABEL_IFACE->link_quality = $3; } | NEXT HOP IPV4 ipa { BABEL_IFACE->next_hop_ip4 = $4; if (!ipa_is_ip4($4)) cf_error("Must be an IPv4 address"); } | NEXT HOP IPV6 ipa { BABEL_IFACE->next_hop_ip6 = $4; if (!ipa_is_ip6($4)) cf_error("Must be an IPv6 address"); } | EXTENDED NEXT HOP bool { BABEL_IFACE->ext_next_hop = $4; } -- 2.41.0

4 14

[PATCH] Bus error on ARMv7 when using OSPF
by Matthew Reeve 18 Dec '24

18 Dec '24

Hi, when using bird 2.0.8 on openwrt 21.02 (and other versions) on a Netgear R7800 router, if the OSPF protocol is used, either v2 or v3, bird immediately crashes on startup with: Fri Jun 11 14:41:11 2021 daemon.info bird: Started Fri Jun 11 14:41:11 2021 kern.err kernel: [ 3500.853248] Alignment trap: not handling instruction f44c0a1f at [<00035848>] Fri Jun 11 14:41:11 2021 kern.alert kernel: [ 3500.853283] 8<--- cut here --- Fri Jun 11 14:41:11 2021 kern.alert kernel: [ 3500.859363] Unhandled fault: alignment exception (0x801) at 0x007e0624 Fri Jun 11 14:41:11 2021 kern.alert kernel: [ 3500.862443] pgd = 0bbef4fd Fri Jun 11 14:41:11 2021 kern.alert kernel: [ 3500.868821] [007e0624] *pgd=5d6ca835, *pte=5c40b75f, *ppte=5c40bc7f This router uses an ARMv7 processor and the issue seems to be to do with memory alignment issues. I've debugged it and traced it to an access to the top_hash_entry struct. I've found that if I add the PACKED macro to the struct definition then it fixes the problem, as per this patch: --- a/proto/ospf/topology.h +++ b/proto/ospf/topology.h @@ -41,7 +41,7 @@ struct top_hash_entry u8 mode; /* LSA generated during RT calculation (LSA_RTCALC or LSA_STALE)*/ u8 nhs_reuse; /* Whether nhs nodes can be reused during merging. See a note in rt.c:add_cand() */ -}; +} PACKED; /* Prevents ospf_hash_find() to ignore the entry, for p->lsrqh and p->lsrth */ Thanks.

4 11

[PATCH v3] Babel: Replace internal route selection by bird's nest
by Daniel Gröber 11 Dec '24

11 Dec '24

This allows for filtering routes from specific interfaces and neighbours. With the current internal route selection proto babel exports only up to one route and an admin cannot do fine-grained filtering. To fix this we rip out the internal route selection entirely and put them all into the bird's nest instead. This appears to not actually be a breaking change as route announcement was already based on which routes bird would send back to babel_rt_notify filters shouldn't be able to tell the difference between a single and multiple routes AFAIK. --- Changes in v3: - Subsume FIB_RESTART v2 patch: instead of restarting FIB iteration we keep lists of actions to perform after FIB iteration is finished. proto/babel/babel.c | 269 +++++++++++++++++++------------------------- proto/babel/babel.h | 8 +- 2 files changed, 120 insertions(+), 157 deletions(-) diff --git a/proto/babel/babel.c b/proto/babel/babel.c index ff8b6b52..087fd95b 100644 --- a/proto/babel/babel.c +++ b/proto/babel/babel.c @@ -29,10 +29,11 @@ * possible routes for the prefix are tracked as &babel_route entries and the * feasibility distance is maintained through &babel_source structures. * - * The main route selection is done in babel_select_route(). This is called when - * an entry is updated by receiving updates from the network or when modified by - * internal timers. The function selects from feasible and reachable routes the - * one with the lowest metric to be announced to the core. + * The main route selection is done by the bird nest (heh). For each prefix we + * export all feasible routes to the core with a distinct source (rte_src) per + * neihbour. Bird will then notify us of the optimal one by calling + * babel_rt_notify and we remember which neighbour it selected in + * babel_entry.selected_nbr. */ #include <stdlib.h> @@ -50,7 +51,7 @@ static inline int ge_mod64k(uint a, uint b) { return (u16)(a - b) < 0x8000; } static void babel_expire_requests(struct babel_proto *p, struct babel_entry *e); -static void babel_select_route(struct babel_proto *p, struct babel_entry *e, struct babel_route *mod); +static void babel_announce_rte(struct babel_proto *p, struct babel_entry *e, struct babel_route *r); static inline void babel_announce_retraction(struct babel_proto *p, struct babel_entry *e); static void babel_send_route_request(struct babel_proto *p, struct babel_entry *e, struct babel_neighbor *n); static void babel_send_seqno_request(struct babel_proto *p, struct babel_entry *e, struct babel_seqno_request *sr, struct babel_neighbor *n); @@ -164,13 +165,19 @@ babel_get_route(struct babel_proto *p, struct babel_entry *e, struct babel_neigh return r; } +static struct babel_route * +babel_get_selected_route(struct babel_proto *p, struct babel_entry *e) +{ + if (e->selected_nbr) + return babel_get_route(p, e, e->selected_nbr); + return NULL; +} + static inline void babel_retract_route(struct babel_proto *p, struct babel_route *r) { r->metric = r->advert_metric = BABEL_INFINITY; - - if (r == r->e->selected) - babel_select_route(p, r->e, r); + babel_announce_rte(p, r->e, r); } static void @@ -182,9 +189,6 @@ babel_flush_route(struct babel_proto *p UNUSED, struct babel_route *r) rem_node(NODE r); rem_node(&r->neigh_route); - if (r->e->selected == r) - r->e->selected = NULL; - sl_free(r); } @@ -200,6 +204,7 @@ babel_expire_route(struct babel_proto *p, struct babel_route *r) { r->metric = r->advert_metric = BABEL_INFINITY; r->expires = current_time() + cf->hold_time; + babel_announce_rte(p, r->e, r); } else { @@ -210,7 +215,7 @@ babel_expire_route(struct babel_proto *p, struct babel_route *r) static void babel_refresh_route(struct babel_proto *p, struct babel_route *r) { - if (r == r->e->selected) + if (r == babel_get_selected_route(p, r->e)) babel_send_route_request(p, r->e, r->neigh); r->refresh_time = 0; @@ -221,16 +226,15 @@ babel_expire_routes_(struct babel_proto *p, struct fib *rtable) { struct babel_config *cf = (void *) p->p.cf; struct babel_route *r, *rx; + struct babel_entry *retract_head = NULL, *delete_head = NULL; + struct babel_route *expire_head = NULL; struct fib_iterator fit; btime now_ = current_time(); - FIB_ITERATE_INIT(&fit, rtable); -loop: + FIB_ITERATE_INIT(&fit, rtable); FIB_ITERATE_START(rtable, &fit, struct babel_entry, e) { - int changed = 0; - WALK_LIST_DELSAFE(r, rx, e->routes) { if (r->refresh_time && r->refresh_time <= now_) @@ -238,23 +242,11 @@ loop: if (r->expires && r->expires <= now_) { - changed = changed || (r == e->selected); - babel_expire_route(p, r); + r->expire_next = expire_head; + expire_head = r; } } - if (changed) - { - /* - * We have to restart the iteration because there may be a cascade of - * synchronous events babel_select_route() -> nest table change -> - * babel_rt_notify() -> rtable change, invalidating hidden variables. - */ - FIB_ITERATE_PUT(&fit); - babel_select_route(p, e, NULL); - goto loop; - } - /* Clean up stale entries */ if ((e->valid == BABEL_ENTRY_STALE) && ((e->updated + cf->hold_time) <= now_)) e->valid = BABEL_ENTRY_DUMMY; @@ -262,9 +254,8 @@ loop: /* Clean up unreachable route */ if (e->unreachable && (!e->valid || (e->router_id == p->router_id))) { - FIB_ITERATE_PUT(&fit); - babel_announce_retraction(p, e); - goto loop; + e->retract_next = retract_head; + retract_head = e; } babel_expire_sources(p, e); @@ -273,12 +264,25 @@ loop: /* Remove empty entries */ if (!e->valid && EMPTY_LIST(e->routes) && EMPTY_LIST(e->sources) && EMPTY_LIST(e->requests)) { - FIB_ITERATE_PUT(&fit); - fib_delete(rtable, e); - goto loop; + e->delete_next = delete_head; + delete_head = e; } } FIB_ITERATE_END; + + for (struct babel_route *r_next, *r = expire_head; r ; r = r_next) { + r_next = r->expire_next; + babel_expire_route(p, r); + } + + for (struct babel_entry *e = retract_head; e ; e = e->retract_next) { + babel_announce_retraction(p, e); + } + + for (struct babel_entry *e_next, *e = delete_head; e ; e = e_next) { + e_next = e->delete_next; + fib_delete(rtable, e); + } } static void @@ -447,6 +451,7 @@ babel_get_neighbor(struct babel_iface *ifa, ip_addr addr) nbr = mb_allocz(ifa->pool, sizeof(struct babel_neighbor)); nbr->ifa = ifa; + nbr->src = rt_get_source(&p->p, idm_alloc(&p->src_ids)); nbr->addr = addr; nbr->rxcost = BABEL_INFINITY; nbr->txcost = BABEL_INFINITY; @@ -474,6 +479,8 @@ babel_flush_neighbor(struct babel_proto *p, struct babel_neighbor *nbr) } nbr->ifa = NULL; + + idm_free(&p->src_ids, nbr->src->private_id); rem_node(NODE nbr); mb_free(nbr); } @@ -634,11 +641,40 @@ done: WALK_LIST2(r, n, nbr->routes, neigh_route) { r->metric = babel_compute_metric(nbr, r->advert_metric); - babel_select_route(p, r->e, r); + babel_announce_rte(p, r->e, r); } } } +static void +babel_announce_rte_unreachable(struct babel_proto *p, struct babel_entry *e, u8 unreachable) +{ + struct channel *c = (e->n.addr->type == NET_IP4) ? p->ip4_channel : p->ip6_channel; + rte *rte = NULL; + + if (unreachable) { + /* Unreachable */ + rta a0 = { + .source = RTS_BABEL, + .scope = SCOPE_UNIVERSE, + .dest = RTD_UNREACHABLE, + .pref = 1, + }; + + rta *a = rta_lookup(&a0); + rte = rte_get_temp(a, p->p.main_source); + } + + e->unreachable = unreachable; + + /* Unlike the many neighbour routes we only want one unreachable route, for + * one it's ugly to have lots of unreachable routes (if we just did this right + * in babel_announce_rte) but we also loose access to the neibour rte_src id + * when the neighbour is deallocated. This happens on a different schedule + * than unreachable route removal. */ + rte_update2(c, e->n.addr, rte, p->p.main_source); +} + /** * babel_announce_rte - announce selected route to the core * @p: Babel protocol instance @@ -649,12 +685,11 @@ done: * the entry is valid and ours, the unreachable route is announced instead. */ static void -babel_announce_rte(struct babel_proto *p, struct babel_entry *e) +babel_announce_rte(struct babel_proto *p, struct babel_entry *e, struct babel_route *r) { - struct babel_route *r = e->selected; struct channel *c = (e->n.addr->type == NET_IP4) ? p->ip4_channel : p->ip6_channel; - if (r) + if (r->metric != BABEL_INFINITY && r->feasible) { rta a0 = { .source = RTS_BABEL, @@ -698,124 +733,27 @@ babel_announce_rte(struct babel_proto *p, struct babel_entry *e) a0.nh.flags = RNF_ONLINK; rta *a = rta_lookup(&a0); - rte *rte = rte_get_temp(a, p->p.main_source); + rte *rte = rte_get_temp(a, r->neigh->src); - e->unreachable = 0; - rte_update2(c, e->n.addr, rte, p->p.main_source); - } - else if (e->valid && (e->router_id != p->router_id)) - { - /* Unreachable */ - rta a0 = { - .source = RTS_BABEL, - .scope = SCOPE_UNIVERSE, - .dest = RTD_UNREACHABLE, - .pref = 1, - }; - - rta *a = rta_lookup(&a0); - rte *rte = rte_get_temp(a, p->p.main_source); - - e->unreachable = 1; - rte_update2(c, e->n.addr, rte, p->p.main_source); + rte_update2(c, e->n.addr, rte, r->neigh->src); + babel_announce_rte_unreachable(p, e, 0); } else - { - /* Retraction */ - e->unreachable = 0; - rte_update2(c, e->n.addr, NULL, p->p.main_source); - } + rte_update2(c, e->n.addr, NULL, r->neigh->src); } /* Special case of babel_announce_rte() just for retraction */ static inline void babel_announce_retraction(struct babel_proto *p, struct babel_entry *e) { + TRACE(D_EVENTS, "Retract unreachable route for %N", + e->n.addr); + struct channel *c = (e->n.addr->type == NET_IP4) ? p->ip4_channel : p->ip6_channel; e->unreachable = 0; rte_update2(c, e->n.addr, NULL, p->p.main_source); } - -/** - * babel_select_route - select best route for given route entry - * @p: Babel protocol instance - * @e: Babel entry to select the best route for - * @mod: Babel route that was modified or NULL if unspecified - * - * Select the best reachable and feasible route for a given prefix among the - * routes received from peers, and propagate it to the nest. This just selects - * the reachable and feasible route with the lowest metric, but keeps selected - * the old one in case of tie. - * - * If no feasible route is available for a prefix that previously had a route - * selected, a seqno request is sent to try to get a valid route. If the entry - * is valid and not owned by us, the unreachable route is announced to the nest - * (to blackhole packets going to it, as per section 2.8). It is later removed - * by babel_expire_routes(). Otherwise, the route is just removed from the nest. - * - * Argument @mod is used to optimize best route calculation. When specified, the - * function can assume that only the @mod route was modified to avoid full best - * route selection and announcement when non-best route was modified in minor - * way. The caller is advised to not call babel_select_route() when no change is - * done (e.g. periodic route updates) to avoid unnecessary announcements of the - * same best route. The caller is not required to call the function in case of a - * retraction of a non-best route. - * - * Note that the function does not active triggered updates. That is done by - * babel_rt_notify() when the change is propagated back to Babel. - */ -static void -babel_select_route(struct babel_proto *p, struct babel_entry *e, struct babel_route *mod) -{ - struct babel_route *r, *best = e->selected; - - /* Shortcut if only non-best was modified */ - if (mod && (mod != best)) - { - /* Either select modified route, or keep old best route */ - if ((mod->metric < (best ? best->metric : BABEL_INFINITY)) && mod->feasible) - best = mod; - else - return; - } - else - { - /* Selected route may be modified and no longer admissible */ - if (!best || (best->metric == BABEL_INFINITY) || !best->feasible) - best = NULL; - - /* Find the best feasible route from all routes */ - WALK_LIST(r, e->routes) - if ((r->metric < (best ? best->metric : BABEL_INFINITY)) && r->feasible) - best = r; - } - - if (best) - { - if (best != e->selected) - TRACE(D_EVENTS, "Picked new route for prefix %N: router-id %lR metric %d", - e->n.addr, best->router_id, best->metric); - } - else if (e->selected) - { - /* - * We have lost all feasible routes. We have to broadcast seqno request - * (Section 3.8.2.1) and keep unreachable route for a while (section 2.8). - * The later is done automatically by babel_announce_rte(). - */ - - TRACE(D_EVENTS, "Lost feasible route for prefix %N", e->n.addr); - if (e->valid && (e->selected->router_id == e->router_id)) - babel_add_seqno_request(p, e, e->selected->router_id, e->selected->seqno + 1, 0, NULL); - } - else - return; - - e->selected = best; - babel_announce_rte(p, e); -} - /* * Functions to send replies */ @@ -1300,7 +1238,7 @@ babel_handle_update(union babel_msg *m, struct babel_iface *ifa) s = babel_find_source(e, msg->router_id); /* for feasibility */ feasible = babel_is_feasible(s, msg->seqno, msg->metric); metric = babel_compute_metric(nbr, msg->metric); - best = e->selected; + best = babel_get_selected_route(p, e); /* * RFC section 3.8.2.2 - Dealing with unfeasible updates. Generate a one-off @@ -1338,7 +1276,7 @@ babel_handle_update(union babel_msg *m, struct babel_iface *ifa) e->updated = current_time(); } - babel_select_route(p, e, r); + babel_announce_rte(p, e, r); } void @@ -2003,10 +1941,10 @@ babel_dump_route(struct babel_route *r) } static void -babel_dump_entry(struct babel_entry *e) +babel_dump_entry(struct babel_proto *p, struct babel_entry *e) { struct babel_source *s; - struct babel_route *r; + struct babel_route *r, *best = babel_get_selected_route(p, e); debug("Babel: Entry %N:\n", e->n.addr); @@ -2016,7 +1954,7 @@ babel_dump_entry(struct babel_entry *e) WALK_LIST(r,e->routes) { debug(" "); - if (r == e->selected) debug("*"); + if (r == best) debug("*"); babel_dump_route(r); } } @@ -2057,12 +1995,12 @@ babel_dump(struct proto *P) FIB_WALK(&p->ip4_rtable, struct babel_entry, e) { - babel_dump_entry(e); + babel_dump_entry(p, e); } FIB_WALK_END; FIB_WALK(&p->ip6_rtable, struct babel_entry, e) { - babel_dump_entry(e); + babel_dump_entry(p, e); } FIB_WALK_END; } @@ -2186,7 +2124,7 @@ babel_show_entries_(struct babel_proto *p, struct fib *rtable) FIB_WALK(rtable, struct babel_entry, e) { - struct babel_route *r = NULL; + struct babel_route *r = NULL, *best = babel_get_selected_route(p, e); uint rts = 0, srcs = 0; node *n; @@ -2199,7 +2137,7 @@ babel_show_entries_(struct babel_proto *p, struct fib *rtable) if (e->valid) cli_msg(-1025, "%-*N %-23lR %6u %5u %7u %7u", width, e->n.addr, e->router_id, e->metric, e->seqno, rts, srcs); - else if (r = e->selected) + else if (r = best) cli_msg(-1025, "%-*N %-23lR %6u %5u %7u %7u", width, e->n.addr, r->router_id, r->metric, r->seqno, rts, srcs); else @@ -2236,10 +2174,10 @@ babel_show_routes_(struct babel_proto *p, struct fib *rtable) FIB_WALK(rtable, struct babel_entry, e) { - struct babel_route *r; + struct babel_route *r, *best = babel_get_selected_route(p, e); WALK_LIST(r, e->routes) { - char c = (r == e->selected) ? '*' : (r->feasible ? '+' : ' '); + char c = (r == best) ? '*' : (r->feasible ? '+' : ' '); btime time = r->expires ? r->expires - current_time() : 0; cli_msg(-1025, "%-*N %-25I %-10s %5u %c %5u %7t", width, e->n.addr, r->next_hop, r->neigh->ifa->ifname, @@ -2320,15 +2258,18 @@ babel_rt_notify(struct proto *P, struct channel *c UNUSED, struct network *net, { struct babel_proto *p = (void *) P; struct babel_entry *e; + struct babel_iface *ifa; + struct babel_neighbor *n; if (new) { /* Update */ + uint internal = new->src->proto == P; uint rt_seqno; uint rt_metric = ea_get_int(new->attrs->eattrs, EA_BABEL_METRIC, 0); u64 rt_router_id = 0; - if (new->src->proto == P) + if (internal) { rt_seqno = ea_find(new->attrs->eattrs, EA_BABEL_SEQNO)->u.data; eattr *e = ea_find(new->attrs->eattrs, EA_BABEL_ROUTER_ID); @@ -2350,6 +2291,18 @@ babel_rt_notify(struct proto *P, struct channel *c UNUSED, struct network *net, e = babel_get_entry(p, net->n.addr); + while (internal) { + ifa = babel_find_iface(p, new->attrs->nh.iface); + if (!ifa) break; + n = babel_find_neighbor(ifa, new->attrs->from); + if (!n) break; + e->selected_nbr = n; + break; + } + if (!internal) { + e->selected_nbr = NULL; + } + /* Activate triggered updates */ if ((e->valid != BABEL_ENTRY_VALID) || (e->router_id != rt_router_id)) @@ -2373,6 +2326,9 @@ babel_rt_notify(struct proto *P, struct channel *c UNUSED, struct network *net, e->valid = BABEL_ENTRY_STALE; e->metric = BABEL_INFINITY; + e->selected_nbr = NULL; + + babel_announce_rte_unreachable(p, e, 1); babel_trigger_update(p); e->updated = current_time(); @@ -2464,6 +2420,7 @@ babel_start(struct proto *P) p->source_slab = sl_new(P->pool, sizeof(struct babel_source)); p->msg_slab = sl_new(P->pool, sizeof(struct babel_msg_node)); p->seqno_slab = sl_new(P->pool, sizeof(struct babel_seqno_request)); + idm_init(&p->src_ids, P->pool, 8); p->log_pkt_tbf = (struct tbf){ .rate = 1, .burst = 5 }; diff --git a/proto/babel/babel.h b/proto/babel/babel.h index da8386b3..1d7e19f0 100644 --- a/proto/babel/babel.h +++ b/proto/babel/babel.h @@ -25,6 +25,7 @@ #include "lib/socket.h" #include "lib/string.h" #include "lib/timer.h" +#include "lib/idm.h" #define EA_BABEL_METRIC EA_CODE(PROTOCOL_BABEL, 0) #define EA_BABEL_ROUTER_ID EA_CODE(PROTOCOL_BABEL, 1) @@ -174,6 +175,7 @@ struct babel_proto { slab *source_slab; slab *msg_slab; slab *seqno_slab; + struct idm src_ids; struct tbf log_pkt_tbf; /* TBF for packet messages */ }; @@ -216,6 +218,7 @@ struct babel_iface { struct babel_neighbor { node n; struct babel_iface *ifa; + struct rte_src *src; ip_addr addr; u16 rxcost; /* Sent in last IHU */ @@ -256,6 +259,7 @@ struct babel_source { struct babel_route { node n; node neigh_route; + struct babel_route *expire_next; struct babel_entry *e; struct babel_neighbor *neigh; @@ -281,7 +285,9 @@ struct babel_seqno_request { }; struct babel_entry { - struct babel_route *selected; + struct babel_neighbor *selected_nbr; + + struct babel_entry *retract_next, *delete_next; list routes; /* Routes for this prefix (struct babel_route) */ list sources; /* Source entries for this prefix (struct babel_source). */ -- 2.30.2

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RE: Bird bfd configuration
by LIU Chris 14 Jun '24

14 Jun '24

Hello, I am trying to configure BFD protocol. If configure 2 instances with below, it doesn't work. So I have to configure one instance, and put all the neighbors list to it. Is it possible to configure separate instance ? The below doesn't work protocol bfd Test1 { interface "eth2" { min rx interval 1000000 us; min tx interval 1000000 us; idle tx interval 3000000 us; multiplier 3; }; neighbor X1.Y1.Z1.A1 local X1.Y1.Z1.B1; } protocol bfd Test2 { interface "eth0" { min rx interval 1000000 us; min tx interval 1000000 us; idle tx interval 3000000 us; multiplier 3; }; neighbor X2.Y2.Z2.A2 local X2.Y2.Z2.B2; } Below it is working, protocol bfd Test { interface "eth*" { min rx interval 1000000 us; min tx interval 1000000 us; idle tx interval 3000000 us; multiplier 3; }; neighbor X1.Y1.Z1.A1 local X1.Y1.Z1.B1; neighbor X2.Y2.Z2.A2 local X2.Y2.Z2.B2; } With best regards, Chris Thales is in the process of carving out its Transportation activity (GTS) from other Thales' activities. In order to prepare this internal restructuring, a new e-mail address has been adopted and your GTS contacts now use urbanandmainlines.com. Please note that their Thales e-mail address remains also valid.

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babel rtt in bird: How to set the RTT equal to the latency?
by Marek Küthe 29 Feb '24

29 Feb '24

Hello, I have seen that in bird 2.14 the babel rtt extension has been implemented. I was very happy about that! Currently I use the following setting of babeld for rtt: ``` default type tunnel rtt-min 1 rtt-max 1001 max-rtt-penalty 1000 enable-timestamps true ``` It causes the RTT to be equal to the latency to the other node. I have seen that there is both rtt-min and rtt-max setting in bird, but no max-rtt-penalty. So my question is how would I represent the above expression in bird? I would be very happy to get an answer! Greetings Marek Küthe -- Marek Küthe m.k(a)mk16.de er/ihm he/him

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Multiple ebgp neighbours to the same peer
by Prem Anand 11 Feb '24

11 Feb '24

Hi all, New user here I am trying to get 2 ebgp neighbours on bird to peer with a remote bgp endpoint on frr node. One between 10.100.101.1 <—> 10.100.1.1 and other between 10.100.102.1 <—> 10.100.1.1 ┌──────────────────┐ ┌─────────────┐ 10.100.101.1 │ │ensp5s0 │ │ loop1 * Bird │◄──────────────────────►┘ Frr │ │ 2.0.10 │10.100.1.2 10.100.1.1 │ loop2 * │ │ │ 10.100.102.1 │ │ │ │ └──────────────────┘ └─────────────┘ I find that only the first ebgp neighbour comes up and moves to "Established” state whereas the second ebgp neighbour remains in “Idle” state. However if I restart the bgp neighbour in “Established” state, the other bgp neighbour comes up and moves to “Established” state, but the restarted one remains in Idle state. Is there any limitation that I can’t have 2 neighbours to the same peer? Or do I have to ensure that the 2 neighbours use different tables? I have already disabled rp_filter sysctl -w net.ipv4.conf.all.rp_filter=0 Regards Prem Config ====== log "/var/log/trex/bird.log" all; debug protocols all; router id 10.100.1.2; protocol device { # scan time 10; interface "loop1"; interface "loop2"; interface "enp5s0"; } protocol bgp bgp_peer1 { local 10.100.101.1 as 65001; neighbor 10.100.1.1 as 65500; ipv4 { import all; export all; }; } protocol bgp bgp_peer2 { local 10.100.102.1 as 65002; neighbor 10.100.1.1 as 65500; ipv4 { import all; export all; }; } protocol static bird_cfg_routes { ipv4 { export all; import all; }; route 200.1.1.1/32 via 10.100.2.100; } Logs ==== bird> show protocols Name Proto Table State Since Info device1 Device --- up 13:05:16.761 bgp_peer1 BGP --- up 13:05:21.497 Established bgp_peer2 BGP --- start 13:05:16.761 Idle bird_cfg_routes Static master4 up 13:05:16.761 bird> bird> bird> bird> restart bgp_peer1 bgp_peer1: restarted bird> bird> bird> show protocols Name Proto Table State Since Info device1 Device --- up 13:05:16.761 bgp_peer1 BGP --- start 13:07:13.673 Idle bgp_peer2 BGP --- up 13:07:18.328 Established bird_cfg_routes Static master4 up 13:05:16.761 bird> show interfaces lo up (index=1) MultiAccess AdminUp LinkUp Loopback Ignored MTU=65536 127.0.0.1/8 (Preferred, scope host) ::1/128 (Preferred, scope host) mgmt0 up (index=2) MultiAccess Broadcast Multicast AdminUp LinkUp MTU=1500 192.168.121.163/24 (Preferred, scope site) fe80::b203:e9ff:fe02:100/64 (Preferred, scope link) enp5s0 up (index=3) MultiAccess Broadcast Multicast AdminUp LinkUp MTU=1500 10.100.1.2/24 (Preferred, scope site) enp6s0 up (index=4) MultiAccess Broadcast Multicast AdminUp LinkUp MTU=1500 10.100.2.1/24 (Preferred, scope site) fc00:64:2::1/120 (Preferred, scope site) fe80::b203:e9ff:fe02:102/64 (Preferred, scope link) loop1 up (index=5) MultiAccess Broadcast Multicast AdminUp LinkUp MTU=1500 10.100.101.1/24 (Preferred, scope site) fe80::78f9:91ff:fe2c:83ed/64 (Preferred, scope link) loop2 up (index=6) MultiAccess Broadcast Multicast AdminUp LinkUp MTU=1500 10.100.102.1/24 (Preferred, scope site) fe80::a4fc:34ff:fefd:11ce/64 (Preferred, scope link) bird> bird> bird> show route all Table master4: 200.1.1.1/32 unicast [bird_cfg_routes 13:05:16.761] * (200) via 10.100.2.100 on enp6s0 Type: static univ bird> Debugs ====== 2023-01-21 13:05:16.761 <TRACE> device1: Initializing 2023-01-21 13:05:16.761 <TRACE> bgp_peer1: Initializing 2023-01-21 13:05:16.761 <TRACE> bgp_peer2: Initializing 2023-01-21 13:05:16.761 <TRACE> bird_cfg_routes: Initializing 2023-01-21 13:05:16.761 <TRACE> device1: Starting 2023-01-21 13:05:16.761 <TRACE> device1: Scanning interfaces 2023-01-21 13:05:16.761 <TRACE> device1: State changed to up 2023-01-21 13:05:16.761 <TRACE> bgp_peer1: Starting 2023-01-21 13:05:16.761 <TRACE> bgp_peer1: State changed to start 2023-01-21 13:05:16.761 <TRACE> bgp_peer2: Starting 2023-01-21 13:05:16.761 <TRACE> bgp_peer2: State changed to start 2023-01-21 13:05:16.761 <TRACE> bird_cfg_routes: Starting 2023-01-21 13:05:16.761 <TRACE> bird_cfg_routes: State changed to up 2023-01-21 13:05:16.761 <TRACE> bird_cfg_routes.ipv4 > added [best] 200.1.1.1/32 unicast 2023-01-21 13:05:16.761 <INFO> Started 2023-01-21 13:05:16.762 <TRACE> bgp_peer1: Started 2023-01-21 13:05:16.762 <TRACE> bgp_peer1: Connect delayed by 5 seconds 2023-01-21 13:05:21.495 <TRACE> bgp_peer1: Connecting to 10.100.1.1 from local address 10.100.101.1 2023-01-21 13:05:21.496 <TRACE> bgp_peer1: Connected 2023-01-21 13:05:21.496 <TRACE> bgp_peer1: Sending OPEN(ver=4,as=65001,hold=240,id=0a640102) 2023-01-21 13:05:21.497 <TRACE> bgp_peer1: Got OPEN(as=65500,hold=30,id=192.168.121.230) 2023-01-21 13:05:21.497 <TRACE> bgp_peer1: Sending KEEPALIVE 2023-01-21 13:05:21.497 <TRACE> bgp_peer1: Got KEEPALIVE 2023-01-21 13:05:21.497 <TRACE> bgp_peer1: BGP session established 2023-01-21 13:05:21.497 <TRACE> bgp_peer1: State changed to up 2023-01-21 13:05:21.497 <TRACE> bgp_peer1.ipv4 < added 200.1.1.1/32 unicast 2023-01-21 13:05:23.049 <TRACE> bgp_peer1: Got UPDATE 2023-01-21 13:05:23.049 <TRACE> bgp_peer1: Got END-OF-RIB 2023-01-21 13:05:23.049 <TRACE> bgp_peer1: Sending UPDATE 2023-01-21 13:05:23.049 <TRACE> bgp_peer1: Sending END-OF-RIB 2023-01-21 13:05:30.958 <TRACE> bgp_peer1: Sending KEEPALIVE 2023-01-21 13:05:31.499 <TRACE> bgp_peer1: Got KEEPALIVE 2023-01-21 13:05:38.689 <TRACE> bgp_peer1: Sending KEEPALIVE 2023-01-21 13:05:41.499 <TRACE> bgp_peer1: Got KEEPALIVE 2023-01-21 13:05:46.842 <TRACE> bgp_peer1: Sending KEEPALIVE 2023-01-21 13:05:51.499 <TRACE> bgp_peer1: Got KEEPALIVE 2023-01-21 13:05:54.864 <TRACE> bgp_peer1: Sending KEEPALIVE 2023-01-21 13:06:01.499 <TRACE> bgp_peer1: Got KEEPALIVE 2023-01-21 13:06:03.759 <TRACE> bgp_peer1: Sending KEEPALIVE 2023-01-21 13:06:11.499 <TRACE> bgp_peer1: Got KEEPALIVE 2023-01-21 13:06:11.843 <TRACE> bgp_peer1: Sending KEEPALIVE 2023-01-21 13:06:16.764 <TRACE> device1: Scanning interfaces ... ... ... 2023-01-21 13:07:13.673 <INFO> Restarting protocol bgp_peer1 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: Shutting down 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: Shutdown requested 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: State changed to stop 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: BGP session closed 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: Sending NOTIFICATION(code=6.4) 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: Down 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: State changed to flush 2023-01-21 13:07:13.673 <TRACE> bgp_peer2: Started 2023-01-21 13:07:13.673 <TRACE> bgp_peer2: Connect delayed by 5 seconds 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: State changed to down 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: Starting 2023-01-21 13:07:13.673 <TRACE> bgp_peer1: State changed to start 2023-01-21 13:07:16.761 <TRACE> device1: Scanning interfaces 2023-01-21 13:07:18.326 <TRACE> bgp_peer2: Connecting to 10.100.1.1 from local address 10.100.102.1 2023-01-21 13:07:18.327 <TRACE> bgp_peer2: Connected 2023-01-21 13:07:18.327 <TRACE> bgp_peer2: Sending OPEN(ver=4,as=65002,hold=240,id=0a640102) 2023-01-21 13:07:18.328 <TRACE> bgp_peer2: Got OPEN(as=65500,hold=30,id=192.168.121.230) 2023-01-21 13:07:18.328 <TRACE> bgp_peer2: Sending KEEPALIVE 2023-01-21 13:07:18.328 <TRACE> bgp_peer2: Got KEEPALIVE 2023-01-21 13:07:18.328 <TRACE> bgp_peer2: BGP session established 2023-01-21 13:07:18.328 <TRACE> bgp_peer2: State changed to up 2023-01-21 13:07:18.328 <TRACE> bgp_peer2.ipv4 < added 200.1.1.1/32 unicast 2023-01-21 13:07:19.880 <TRACE> bgp_peer2: Got UPDATE 2023-01-21 13:07:19.880 <TRACE> bgp_peer2: Got END-OF-RIB 2023-01-21 13:07:19.880 <TRACE> bgp_peer2: Sending UPDATE 2023-01-21 13:07:19.880 <TRACE> bgp_peer2: Sending END-OF-RIB 2023-01-21 13:07:27.298 <TRACE> bgp_peer2: Sending KEEPALIVE 2023-01-21 13:07:28.329 <TRACE> bgp_peer2: Got KEEPALIVE 2023-01-21 13:07:36.478 <TRACE> bgp_peer2: Sending KEEPALIVE

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dumping BGP4MP* data
by Ioannis Paterakis 05 Jan '24

05 Jan '24

Dear bird-users, Thank you very much for the acceptance on this list. Excuses if this question has been placed here before but I couldn’t find anything in the archives or in any documentation available. Is there a way to dump mrt files from bird with bgp updates (BGP4MP*) data only? Thank you very much in advance, Ioannis

2 2

logging via udp
by Alexander Zubkov 13 Dec '23

13 Dec '23

Hello, Made some dirty patch for myself to allow bird to send logs via udp. But it may be useful not only for me, so posting it here. It could be useful when server experiencing high IO-load. As syslog and file operations in bird are blocking, it can be blocked on writing to it for indefinite time, which could lead to various problems like protocol timeouts. So udp logging comes in handy here. The tradeoff is that we can miss some logs if they are not processed in time. You can specify udp log destination like that: log udp [host IP|"hostname"] [port NUMBER|"portname"] ... By default it uses destination ip 127.0.0.1 and port 514. There are some constraints like not much error handling. And this destination replaces file destination, i.e. you can not use those simultaneously and it may leak descriptors and some memory probably if both are specified. It also makes a new socket every time configuration is reloaded even if there is no change in options, but this is not a great deal.

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Re: [Babel-users] [RFC] Replace WireGuard AllowedIPs with IP route attribute
by Daniel Gröber 22 Nov '23

22 Nov '23

Hi Kyle, On Mon, Aug 28, 2023 at 11:40:48AM -0400, Kyle Rose wrote: > On Sat, Aug 19, 2023 at 5:25 PM Daniel Gröber <dxld(a)darkboxed.org> wrote: > > Having read Kyle's use-case I'm thinking my original plan to extend the wg > > internal source-address filtering to use a rt lookup with our new attribute > > would not be maximally useful so now my thinking is we should just have a > > boolean toggle to disable it explicitly per device. > > If there is interest among the maintainers in eventually merging a > change with a per-interface knob to turn off the source IP check, I > will go through the trouble of putting together an initial pass at > this. I don't want to spend the time if there is firm opposition to > the idea. I think just a patch to turn off the wg source IP check is not very useful at the moment. It would encourage bad source IP filtering practices when multiple peers are involved as no mechanism for identifying the sending peer is available at the policy routing or netfilter level currently. I think such a patch would have to get merged after some kind of mechanism to identify and filter based on the sending wg peer is available. So if you want to move this along I would suggest working on this first. Since I'm also interested in having this feature I'm happy collaborate. It's just hard to find the motivation for writing more wg patches when my pending ones have (mostly) been lying around for a year without a response, but if you're also keen on this feature I'm sure it's easier to stay motivated together :) If my kernel patches go ignored for too long too I'll probably just resort to getting a forked DKMS wireguard module into Debian with this work. Perhaps that approach (or a package in a different distro) would work for your use-case too? --Daniel

5 10

BIRD and IETF 118
by Maria Matejka 07 Nov '23

07 Nov '23

Hello! Just a short reminder for those attending IETF 118 – we aren't officially attending, anyway, if you wish to meet us, please let us know preferably during this week and we may do some BIRD meetup. Have a nice journey to Prague and remember, we have the 2nd best[1] public transportation network in the world, no need for taxi here ;o) Maria [1] https://www.timeout.com/travel/best-public-transport-in-the-world -- Maria Matejka (she/her) | BIRD Team Leader | CZ.NIC, z.s.p.o.

2 3