/* * BIRD -- Management of Interfaces and Neighbor Cache * * (c) 1998--2000 Martin Mares <mj@ucw.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ /** * DOC: Interfaces * * The interface module keeps track of all network interfaces in the * system and their addresses. * * Each interface is represented by an &iface structure which carries * interface capability flags (%IF_MULTIACCESS, %IF_BROADCAST etc.), * MTU, interface name and index and finally a linked list of network * prefixes assigned to the interface, each one represented by * struct &ifa. * * The interface module keeps a `soft-up' state for each &iface which * is a conjunction of link being up, the interface being of a `sane' * type and at least one IP address assigned to it. */ #undef LOCAL_DEBUG #include "nest/bird.h" #include "nest/iface.h" #include "nest/protocol.h" #include "nest/cli.h" #include "lib/resource.h" #include "lib/string.h" #include "conf/conf.h" #include "sysdep/unix/krt.h" static pool *if_pool; list iface_list; static void if_recalc_preferred(struct iface *i); /** * ifa_dump - dump interface address * @a: interface address descriptor * * This function dumps contents of an &ifa to the debug output. */ void ifa_dump(struct ifa *a) { debug("\t%I, net %N bc %I -> %I%s%s%s%s\n", a->ip, &a->prefix, a->brd, a->opposite, (a->flags & IA_PRIMARY) ? " PRIMARY" : "", (a->flags & IA_SECONDARY) ? " SEC" : "", (a->flags & IA_HOST) ? " HOST" : "", (a->flags & IA_PEER) ? " PEER" : ""); } /** * if_dump - dump interface * @i: interface to dump * * This function dumps all information associated with a given * network interface to the debug output. */ void if_dump(struct iface *i) { struct ifa *a; debug("IF%d: %s", i->index, i->name); if (i->flags & IF_SHUTDOWN) debug(" SHUTDOWN"); if (i->flags & IF_UP) debug(" UP"); else debug(" DOWN"); if (i->flags & IF_ADMIN_UP) debug(" LINK-UP"); if (i->flags & IF_MULTIACCESS) debug(" MA"); if (i->flags & IF_BROADCAST) debug(" BC"); if (i->flags & IF_MULTICAST) debug(" MC"); if (i->flags & IF_LOOPBACK) debug(" LOOP"); if (i->flags & IF_IGNORE) debug(" IGN"); if (i->flags & IF_TMP_DOWN) debug(" TDOWN"); debug(" MTU=%d\n", i->mtu); WALK_LIST(a, i->addrs) { ifa_dump(a); ASSERT(!!(a->flags & IA_PRIMARY) == ((a == i->addr4) || (a == i->addr6) || (a == i->llv6))); } } /** * if_dump_all - dump all interfaces * * This function dumps information about all known network * interfaces to the debug output. */ void if_dump_all(void) { struct iface *i; debug("Known network interfaces:\n"); WALK_LIST(i, iface_list) if_dump(i); debug("Router ID: %08x\n", config->router_id); } static inline unsigned if_what_changed(struct iface *i, struct iface *j) { unsigned c; if (((i->flags ^ j->flags) & ~(IF_UP | IF_SHUTDOWN | IF_UPDATED | IF_ADMIN_UP | IF_LINK_UP | IF_TMP_DOWN | IF_JUST_CREATED)) || (i->index != j->index) || (i->master != j->master)) return IF_CHANGE_TOO_MUCH; c = 0; if ((i->flags ^ j->flags) & IF_UP) c |= (i->flags & IF_UP) ? IF_CHANGE_DOWN : IF_CHANGE_UP; if ((i->flags ^ j->flags) & IF_LINK_UP) c |= IF_CHANGE_LINK; if (i->mtu != j->mtu) c |= IF_CHANGE_MTU; return c; } static inline void if_copy(struct iface *to, struct iface *from) { to->flags = from->flags | (to->flags & IF_TMP_DOWN); to->mtu = from->mtu; to->master_index = from->master_index; to->master = from->master; } static inline void ifa_send_notify(struct proto *p, unsigned c, struct ifa *a) { if (p->ifa_notify && (p->proto_state != PS_DOWN) && (!p->vrf_set || p->vrf == a->iface->master)) { if (p->debug & D_IFACES) log(L_TRACE "%s < address %N on interface %s %s", p->name, &a->prefix, a->iface->name, (c & IF_CHANGE_UP) ? "added" : "removed"); p->ifa_notify(p, c, a); } } static void ifa_notify_change_(unsigned c, struct ifa *a) { struct proto *p; DBG("IFA change notification (%x) for %s:%I\n", c, a->iface->name, a->ip); WALK_LIST(p, proto_list) ifa_send_notify(p, c, a); } static inline void ifa_notify_change(unsigned c, struct ifa *a) { if (c & IF_CHANGE_DOWN) neigh_ifa_down(a); ifa_notify_change_(c, a); if (c & IF_CHANGE_UP) neigh_ifa_up(a); } static inline void if_send_notify(struct proto *p, unsigned c, struct iface *i) { if (p->if_notify && (p->proto_state != PS_DOWN) && (!p->vrf_set || p->vrf == i->master)) { if (p->debug & D_IFACES) log(L_TRACE "%s < interface %s %s", p->name, i->name, (c & IF_CHANGE_UP) ? "goes up" : (c & IF_CHANGE_DOWN) ? "goes down" : (c & IF_CHANGE_MTU) ? "changes MTU" : (c & IF_CHANGE_LINK) ? "changes link" : (c & IF_CHANGE_PREFERRED) ? "changes preferred address" : (c & IF_CHANGE_CREATE) ? "created" : "sends unknown event"); p->if_notify(p, c, i); } } static void if_notify_change(unsigned c, struct iface *i) { struct proto *p; struct ifa *a; if (i->flags & IF_JUST_CREATED) { i->flags &= ~IF_JUST_CREATED; c |= IF_CHANGE_CREATE | IF_CHANGE_MTU; } DBG("Interface change notification (%x) for %s\n", c, i->name); #ifdef LOCAL_DEBUG if_dump(i); #endif if (c & IF_CHANGE_DOWN) neigh_if_down(i); if (c & IF_CHANGE_DOWN) WALK_LIST(a, i->addrs) ifa_notify_change_(IF_CHANGE_DOWN, a); WALK_LIST(p, proto_list) if_send_notify(p, c, i); if (c & IF_CHANGE_UP) WALK_LIST(a, i->addrs) ifa_notify_change_(IF_CHANGE_UP, a); if (c & IF_CHANGE_UP) neigh_if_up(i); if ((c & (IF_CHANGE_UP | IF_CHANGE_DOWN | IF_CHANGE_LINK)) == IF_CHANGE_LINK) neigh_if_link(i); } static uint if_recalc_flags(struct iface *i UNUSED, uint flags) { if ((flags & IF_ADMIN_UP) && !(flags & (IF_SHUTDOWN | IF_TMP_DOWN)) && !(i->master_index && !i->master)) flags |= IF_UP; else flags &= ~IF_UP; return flags; } static void if_change_flags(struct iface *i, uint flags) { uint of = i->flags; i->flags = if_recalc_flags(i, flags); if ((i->flags ^ of) & IF_UP) if_notify_change((i->flags & IF_UP) ? IF_CHANGE_UP : IF_CHANGE_DOWN, i); } /** * if_delete - remove interface * @old: interface * * This function is called by the low-level platform dependent code * whenever it notices an interface disappears. It is just a shorthand * for if_update(). */ void if_delete(struct iface *old) { struct iface f = {}; strncpy(f.name, old->name, sizeof(f.name)-1); f.flags = IF_SHUTDOWN; if_update(&f); } /** * if_update - update interface status * @new: new interface status * * if_update() is called by the low-level platform dependent code * whenever it notices an interface change. * * There exist two types of interface updates -- synchronous and asynchronous * ones. In the synchronous case, the low-level code calls if_start_update(), * scans all interfaces reported by the OS, uses if_update() and ifa_update() * to pass them to the core and then it finishes the update sequence by * calling if_end_update(). When working asynchronously, the sysdep code * calls if_update() and ifa_update() whenever it notices a change. * * if_update() will automatically notify all other modules about the change. */ struct iface * if_update(struct iface *new) { struct iface *i; unsigned c; WALK_LIST(i, iface_list) if (!strcmp(new->name, i->name)) { new->flags = if_recalc_flags(new, new->flags); c = if_what_changed(i, new); if (c & IF_CHANGE_TOO_MUCH) /* Changed a lot, convert it to down/up */ { DBG("Interface %s changed too much -- forcing down/up transition\n", i->name); if_change_flags(i, i->flags | IF_TMP_DOWN); rem_node(&i->n); new->addr4 = i->addr4; new->addr6 = i->addr6; new->llv6 = i->llv6; new->sysdep = i->sysdep; memcpy(&new->addrs, &i->addrs, sizeof(i->addrs)); memcpy(i, new, sizeof(*i)); i->flags &= ~IF_UP; /* IF_TMP_DOWN will be added later */ goto newif; } if_copy(i, new); if (c) if_notify_change(c, i); i->flags |= IF_UPDATED; return i; } i = mb_alloc(if_pool, sizeof(struct iface)); memcpy(i, new, sizeof(*i)); init_list(&i->addrs); newif: init_list(&i->neighbors); i->flags |= IF_UPDATED | IF_TMP_DOWN; /* Tmp down as we don't have addresses yet */ add_tail(&iface_list, &i->n); return i; } void if_start_update(void) { struct iface *i; struct ifa *a; WALK_LIST(i, iface_list) { i->flags &= ~IF_UPDATED; WALK_LIST(a, i->addrs) a->flags &= ~IA_UPDATED; } } void if_end_partial_update(struct iface *i) { if (i->flags & IF_NEEDS_RECALC) if_recalc_preferred(i); if (i->flags & IF_TMP_DOWN) if_change_flags(i, i->flags & ~IF_TMP_DOWN); } void if_end_update(void) { struct iface *i; struct ifa *a, *b; WALK_LIST(i, iface_list) { if (!(i->flags & IF_UPDATED)) if_change_flags(i, (i->flags & ~IF_ADMIN_UP) | IF_SHUTDOWN); else { WALK_LIST_DELSAFE(a, b, i->addrs) if (!(a->flags & IA_UPDATED)) ifa_delete(a); if_end_partial_update(i); } } } void if_flush_ifaces(struct proto *p) { if (p->debug & D_EVENTS) log(L_TRACE "%s: Flushing interfaces", p->name); if_start_update(); if_end_update(); } /** * if_feed_baby - advertise interfaces to a new protocol * @p: protocol to feed * * When a new protocol starts, this function sends it a series * of notifications about all existing interfaces. */ void if_feed_baby(struct proto *p) { struct iface *i; struct ifa *a; if (!p->if_notify && !p->ifa_notify) /* shortcut */ return; DBG("Announcing interfaces to new protocol %s\n", p->name); WALK_LIST(i, iface_list) { if_send_notify(p, IF_CHANGE_CREATE | ((i->flags & IF_UP) ? IF_CHANGE_UP : 0), i); if (i->flags & IF_UP) WALK_LIST(a, i->addrs) ifa_send_notify(p, IF_CHANGE_CREATE | IF_CHANGE_UP, a); } } /** * if_find_by_index - find interface by ifindex * @idx: ifindex * * This function finds an &iface structure corresponding to an interface * of the given index @idx. Returns a pointer to the structure or %NULL * if no such structure exists. */ struct iface * if_find_by_index(unsigned idx) { struct iface *i; WALK_LIST(i, iface_list) if (i->index == idx && !(i->flags & IF_SHUTDOWN)) return i; return NULL; } /** * if_find_by_name - find interface by name * @name: interface name * * This function finds an &iface structure corresponding to an interface * of the given name @name. Returns a pointer to the structure or %NULL * if no such structure exists. */ struct iface * if_find_by_name(const char *name) { struct iface *i; WALK_LIST(i, iface_list) if (!strcmp(i->name, name) && !(i->flags & IF_SHUTDOWN)) return i; return NULL; } struct iface * if_get_by_name(const char *name) { struct iface *i; WALK_LIST(i, iface_list) if (!strcmp(i->name, name)) return i; /* No active iface, create a dummy */ i = mb_allocz(if_pool, sizeof(struct iface)); strncpy(i->name, name, sizeof(i->name)-1); i->flags = IF_SHUTDOWN; init_list(&i->addrs); init_list(&i->neighbors); add_tail(&iface_list, &i->n); return i; } static inline void if_set_preferred(struct ifa **pos, struct ifa *new) { if (*pos) (*pos)->flags &= ~IA_PRIMARY; if (new) new->flags |= IA_PRIMARY; *pos = new; } static void if_recalc_preferred(struct iface *i) { /* * Preferred address selection priority: * 1) Address configured in Device protocol * 2) Sysdep IPv4 address (BSD) * 3) Old preferred address * 4) First address in list */ struct kif_iface_config *ic = kif_get_iface_config(i); struct ifa *a4 = i->addr4, *a6 = i->addr6, *ll = i->llv6; ip_addr pref_v4 = ic->pref_v4; uint change = 0; if (kif_update_sysdep_addr(i)) change |= IF_CHANGE_SYSDEP; /* BSD sysdep address */ if (ipa_zero(pref_v4) && ip4_nonzero(i->sysdep)) pref_v4 = ipa_from_ip4(i->sysdep); struct ifa *a; WALK_LIST(a, i->addrs) { /* Secondary address is never selected */ if (a->flags & IA_SECONDARY) continue; if (ipa_is_ip4(a->ip)) { if (!a4 || ipa_equal(a->ip, pref_v4)) a4 = a; } else if (!ipa_is_link_local(a->ip)) { if (!a6 || ipa_equal(a->ip, ic->pref_v6)) a6 = a; } else { if (!ll || ipa_equal(a->ip, ic->pref_ll)) ll = a; } } if ((a4 != i->addr4) || (i->flags & IF_LOST_ADDR4)) { if_set_preferred(&i->addr4, a4); change |= IF_CHANGE_ADDR4; } if ((a6 != i->addr6) || (i->flags & IF_LOST_ADDR6)) { if_set_preferred(&i->addr6, a6); change |= IF_CHANGE_ADDR6; } if ((ll != i->llv6) || (i->flags & IF_LOST_LLV6)) { if_set_preferred(&i->llv6, ll); change |= IF_CHANGE_LLV6; } i->flags &= ~(IF_NEEDS_RECALC | IF_LOST_ADDR4 | IF_LOST_ADDR6 | IF_LOST_LLV6); if (change) if_notify_change(change, i); } void if_recalc_all_preferred_addresses(void) { struct iface *i; WALK_LIST(i, iface_list) { if_recalc_preferred(i); if (i->flags & IF_TMP_DOWN) if_change_flags(i, i->flags & ~IF_TMP_DOWN); } } static inline int ifa_same(struct ifa *a, struct ifa *b) { return ipa_equal(a->ip, b->ip) && net_equal(&a->prefix, &b->prefix); } /** * ifa_update - update interface address * @a: new interface address * * This function adds address information to a network * interface. It's called by the platform dependent code during * the interface update process described under if_update(). */ struct ifa * ifa_update(struct ifa *a) { struct iface *i = a->iface; struct ifa *b; WALK_LIST(b, i->addrs) if (ifa_same(b, a)) { if (ipa_equal(b->brd, a->brd) && ipa_equal(b->opposite, a->opposite) && b->scope == a->scope && !((b->flags ^ a->flags) & IA_PEER)) { b->flags |= IA_UPDATED; return b; } ifa_delete(b); break; } if ((a->prefix.type == NET_IP4) && (i->flags & IF_BROADCAST) && ipa_zero(a->brd)) log(L_WARN "Missing broadcast address for interface %s", i->name); b = mb_alloc(if_pool, sizeof(struct ifa)); memcpy(b, a, sizeof(struct ifa)); add_tail(&i->addrs, &b->n); b->flags |= IA_UPDATED; i->flags |= IF_NEEDS_RECALC; if (i->flags & IF_UP) ifa_notify_change(IF_CHANGE_CREATE | IF_CHANGE_UP, b); return b; } /** * ifa_delete - remove interface address * @a: interface address * * This function removes address information from a network * interface. It's called by the platform dependent code during * the interface update process described under if_update(). */ void ifa_delete(struct ifa *a) { struct iface *i = a->iface; struct ifa *b; WALK_LIST(b, i->addrs) if (ifa_same(b, a)) { rem_node(&b->n); if (b->flags & IA_PRIMARY) { /* * We unlink deleted preferred address and mark for recalculation. * FIXME: This could break if we make iface scan non-atomic, as * protocols still could use the freed address until they get * if_notify from preferred route recalculation. We should fix and * simplify this in the future by having struct ifa refcounted */ if (b == i->addr4) { i->addr4 = NULL; i->flags |= IF_LOST_ADDR4; } if (b == i->addr6) { i->addr6 = NULL; i->flags |= IF_LOST_ADDR6; } if (b == i->llv6) { i->llv6 = NULL; i->flags |= IF_LOST_LLV6; } i->flags |= IF_NEEDS_RECALC; } if (i->flags & IF_UP) ifa_notify_change(IF_CHANGE_DOWN, b); mb_free(b); return; } } u32 if_choose_router_id(struct iface_patt *mask, u32 old_id) { struct iface *i; struct ifa *a, *b; b = NULL; WALK_LIST(i, iface_list) { if (!(i->flags & IF_ADMIN_UP) || (i->flags & IF_SHUTDOWN)) continue; WALK_LIST(a, i->addrs) { if (a->prefix.type != NET_IP4) continue; if (a->flags & IA_SECONDARY) continue; if (a->scope <= SCOPE_LINK) continue; /* Check pattern if specified */ if (mask && !iface_patt_match(mask, i, a)) continue; /* No pattern or pattern matched */ if (!b || ipa_to_u32(a->ip) < ipa_to_u32(b->ip)) b = a; } } if (!b) return 0; u32 id = ipa_to_u32(b->ip); if (id != old_id) log(L_INFO "Chosen router ID %R according to interface %s", id, b->iface->name); return id; } /** * if_init - initialize interface module * * This function is called during BIRD startup to initialize * all data structures of the interface module. */ void if_init(void) { if_pool = rp_new(&root_pool, "Interfaces"); init_list(&iface_list); neigh_init(if_pool); } /* * Interface Pattern Lists */ int iface_patt_match(struct iface_patt *ifp, struct iface *i, struct ifa *a) { struct iface_patt_node *p; WALK_LIST(p, ifp->ipn_list) { const char *t = p->pattern; int pos = p->positive; if (t) { if (*t == '-') { t++; pos = !pos; } if (!patmatch(t, i->name)) continue; } if (p->prefix.pxlen == 0) return pos; if (!a) continue; if (ipa_in_netX(a->ip, &p->prefix)) return pos; if ((a->flags & IA_PEER) && ipa_in_netX(a->opposite, &p->prefix)) return pos; continue; } return 0; } struct iface_patt * iface_patt_find(list *l, struct iface *i, struct ifa *a) { struct iface_patt *p; WALK_LIST(p, *l) if (iface_patt_match(p, i, a)) return p; return NULL; } static int iface_plists_equal(struct iface_patt *pa, struct iface_patt *pb) { struct iface_patt_node *x, *y; x = HEAD(pa->ipn_list); y = HEAD(pb->ipn_list); while (x->n.next && y->n.next) { if ((x->positive != y->positive) || (!x->pattern && y->pattern) || /* This nasty lines where written by me... :-( Feela */ (!y->pattern && x->pattern) || ((x->pattern != y->pattern) && strcmp(x->pattern, y->pattern)) || !net_equal(&x->prefix, &y->prefix)) return 0; x = (void *) x->n.next; y = (void *) y->n.next; } return (!x->n.next && !y->n.next); } int iface_patts_equal(list *a, list *b, int (*comp)(struct iface_patt *, struct iface_patt *)) { struct iface_patt *x, *y; x = HEAD(*a); y = HEAD(*b); while (x->n.next && y->n.next) { if (!iface_plists_equal(x, y) || (comp && !comp(x, y))) return 0; x = (void *) x->n.next; y = (void *) y->n.next; } return (!x->n.next && !y->n.next); } /* * CLI commands. */ static void if_show_addr(struct ifa *a) { byte *flg, opp[IPA_MAX_TEXT_LENGTH + 16]; flg = (a->flags & IA_PRIMARY) ? "Preferred, " : (a->flags & IA_SECONDARY) ? "Secondary, " : ""; if (ipa_nonzero(a->opposite)) bsprintf(opp, "opposite %I, ", a->opposite); else opp[0] = 0; cli_msg(-1003, "\t%I/%d (%s%sscope %s)", a->ip, a->prefix.pxlen, flg, opp, ip_scope_text(a->scope)); } void if_show(void) { struct iface *i; struct ifa *a; char *type; WALK_LIST(i, iface_list) { if (i->flags & IF_SHUTDOWN) continue; char mbuf[16 + sizeof(i->name)] = {}; if (i->master) bsprintf(mbuf, " master=%s", i->master->name); else if (i->master_index) bsprintf(mbuf, " master=#%u", i->master_index); cli_msg(-1001, "%s %s (index=%d%s)", i->name, (i->flags & IF_UP) ? "up" : "down", i->index, mbuf); if (!(i->flags & IF_MULTIACCESS)) type = "PtP"; else type = "MultiAccess"; cli_msg(-1004, "\t%s%s%s Admin%s Link%s%s%s MTU=%d", type, (i->flags & IF_BROADCAST) ? " Broadcast" : "", (i->flags & IF_MULTICAST) ? " Multicast" : "", (i->flags & IF_ADMIN_UP) ? "Up" : "Down", (i->flags & IF_LINK_UP) ? "Up" : "Down", (i->flags & IF_LOOPBACK) ? " Loopback" : "", (i->flags & IF_IGNORE) ? " Ignored" : "", i->mtu); WALK_LIST(a, i->addrs) if (a->prefix.type == NET_IP4) if_show_addr(a); WALK_LIST(a, i->addrs) if (a->prefix.type == NET_IP6) if_show_addr(a); } cli_msg(0, ""); } void if_show_summary(void) { struct iface *i; cli_msg(-2005, "%-10s %-6s %-18s %s", "Interface", "State", "IPv4 address", "IPv6 address"); WALK_LIST(i, iface_list) { byte a4[IPA_MAX_TEXT_LENGTH + 17]; byte a6[IPA_MAX_TEXT_LENGTH + 17]; if (i->flags & IF_SHUTDOWN) continue; if (i->addr4) bsprintf(a4, "%I/%d", i->addr4->ip, i->addr4->prefix.pxlen); else a4[0] = 0; if (i->addr6) bsprintf(a6, "%I/%d", i->addr6->ip, i->addr6->prefix.pxlen); else a6[0] = 0; cli_msg(-1005, "%-10s %-6s %-18s %s", i->name, (i->flags & IF_UP) ? "up" : "down", a4, a6); } cli_msg(0, ""); }