/* * BIRD -- Table-to-Table Routing Protocol a.k.a Pipe * * (c) 1999--2000 Martin Mares <mj@ucw.cz> * * Can be freely distributed and used under the terms of the GNU GPL. */ /** * DOC: Pipe * * The Pipe protocol is very simple. It just connects to two routing tables * using proto_add_announce_hook() and whenever it receives a rt_notify() * about a change in one of the tables, it converts it to a rte_update() * in the other one. * * To avoid pipe loops, Pipe keeps a `being updated' flag in each routing * table. */ #undef LOCAL_DEBUG #include "nest/bird.h" #include "nest/iface.h" #include "nest/protocol.h" #include "nest/route.h" #include "conf/conf.h" #include "filter/filter.h" #include "lib/string.h" #include "pipe.h" static void pipe_send(struct pipe_proto *p, rtable *dest, net *n, rte *new, rte *old UNUSED, ea_list *attrs) { net *nn; rte *e; rta a; if (dest->pipe_busy) { log(L_ERR "Pipe loop detected when sending %I/%d to table %s", n->n.prefix, n->n.pxlen, dest->name); return; } nn = net_get(dest, n->n.prefix, n->n.pxlen); if (new) { memcpy(&a, new->attrs, sizeof(rta)); a.proto = &p->p; a.source = RTS_PIPE; a.aflags = 0; a.eattrs = attrs; e = rte_get_temp(&a); e->net = nn; } else e = NULL; dest->pipe_busy = 1; rte_update(dest, nn, &p->p, e); dest->pipe_busy = 0; } static void pipe_rt_notify_pri(struct proto *P, net *net, rte *new, rte *old, ea_list *attrs) { struct pipe_proto *p = (struct pipe_proto *) P; DBG("PIPE %c> %I/%d\n", (new ? '+' : '-'), net->n.prefix, net->n.pxlen); pipe_send(p, p->peer, net, new, old, attrs); } static void pipe_rt_notify_sec(struct proto *P, net *net, rte *new, rte *old, ea_list *attrs) { struct pipe_proto *p = ((struct pipe_proto *) P)->phantom; DBG("PIPE %c< %I/%d\n", (new ? '+' : '-'), net->n.prefix, net->n.pxlen); pipe_send(p, p->p.table, net, new, old, attrs); } static int pipe_import_control(struct proto *P, rte **ee, ea_list **ea UNUSED, struct linpool *p UNUSED) { struct proto *pp = (*ee)->attrs->proto; if (pp == P || pp == &((struct pipe_proto *) P)->phantom->p) return -1; /* Avoid local loops automatically */ return 0; } static int pipe_start(struct proto *P) { struct pipe_proto *p = (struct pipe_proto *) P; struct pipe_proto *ph; struct announce_hook *a; /* * Create a phantom protocol which will represent the remote * end of the pipe (we need to do this in order to get different * filters and announce functions and it unfortunately involves * a couple of magic trickery). */ ph = mb_alloc(P->pool, sizeof(struct pipe_proto)); memcpy(ph, p, sizeof(struct pipe_proto)); p->phantom = ph; ph->phantom = p; ph->p.rt_notify = pipe_rt_notify_sec; ph->p.proto_state = PS_UP; ph->p.core_state = ph->p.core_goal = FS_HAPPY; ph->p.in_filter = ph->p.out_filter = FILTER_ACCEPT; /* We do all filtering on the local end */ /* * Connect the phantom protocol to the peer routing table, but * keep it in the list of connections of the primary protocol, * so that it gets disconnected at the right time and we also * get all routes from both sides during the feeding phase. */ a = proto_add_announce_hook(P, p->peer); a->proto = &ph->p; rt_lock_table(p->peer); return PS_UP; } static int pipe_shutdown(struct proto *P) { struct pipe_proto *p = (struct pipe_proto *) P; rt_unlock_table(p->peer); return PS_DOWN; } static struct proto * pipe_init(struct proto_config *C) { struct pipe_config *c = (struct pipe_config *) C; struct proto *P = proto_new(C, sizeof(struct pipe_proto)); struct pipe_proto *p = (struct pipe_proto *) P; p->peer = c->peer->table; P->rt_notify = pipe_rt_notify_pri; P->import_control = pipe_import_control; return P; } static void pipe_postconfig(struct proto_config *C) { struct pipe_config *c = (struct pipe_config *) C; if (!c->peer) cf_error("Name of peer routing table not specified"); if (c->peer == C->table) cf_error("Primary table and peer table must be different"); } static void pipe_get_status(struct proto *P, byte *buf) { struct pipe_proto *p = (struct pipe_proto *) P; bsprintf(buf, "-> %s", p->peer->name); } static int pipe_reconfigure(struct proto *p, struct proto_config *new) { struct pipe_config *o = (struct pipe_config *) p->cf; struct pipe_config *n = (struct pipe_config *) new; return o->peer == n->peer; } struct protocol proto_pipe = { name: "Pipe", template: "pipe%d", postconfig: pipe_postconfig, init: pipe_init, start: pipe_start, shutdown: pipe_shutdown, reconfigure: pipe_reconfigure, get_status: pipe_get_status, };