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b940579115
A filter should log messages only if executed explicitly (e.g., during route export or route import). When a filter is executed for technical reasons (e.g., to establish whether a route was exported before), it should run silently.
1282 lines
28 KiB
C
1282 lines
28 KiB
C
/*
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* BIRD -- UNIX Kernel Synchronization
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*
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* (c) 1998--2000 Martin Mares <mj@ucw.cz>
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*
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* Can be freely distributed and used under the terms of the GNU GPL.
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*/
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/**
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* DOC: Kernel synchronization
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*
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* This system dependent module implements the Kernel and Device protocol,
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* that is synchronization of interface lists and routing tables with the
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* OS kernel.
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*
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* The whole kernel synchronization is a bit messy and touches some internals
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* of the routing table engine, because routing table maintenance is a typical
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* example of the proverbial compatibility between different Unices and we want
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* to keep the overhead of our KRT business as low as possible and avoid maintaining
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* a local routing table copy.
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*
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* The kernel syncer can work in three different modes (according to system config header):
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* Either with a single routing table and single KRT protocol [traditional UNIX]
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* or with many routing tables and separate KRT protocols for all of them
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* or with many routing tables, but every scan including all tables, so we start
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* separate KRT protocols which cooperate with each other [Linux].
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* In this case, we keep only a single scan timer.
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*
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* We use FIB node flags in the routing table to keep track of route
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* synchronization status. We also attach temporary &rte's to the routing table,
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* but it cannot do any harm to the rest of BIRD since table synchronization is
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* an atomic process.
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*
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* When starting up, we cheat by looking if there is another
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* KRT instance to be initialized later and performing table scan
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* only once for all the instances.
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*
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* The code uses OS-dependent parts for kernel updates and scans. These parts are
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* in more specific sysdep directories (e.g. sysdep/linux) in functions krt_sys_*
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* and kif_sys_* (and some others like krt_replace_rte()) and krt-sys.h header file.
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* This is also used for platform specific protocol options and route attributes.
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*
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* There was also an old code that used traditional UNIX ioctls for these tasks.
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* It was unmaintained and later removed. For reference, see sysdep/krt-* files
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* in commit 396dfa9042305f62da1f56589c4b98fac57fc2f6
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*/
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/*
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* If you are brave enough, continue now. You cannot say you haven't been warned.
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*/
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#undef LOCAL_DEBUG
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#include "nest/bird.h"
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#include "nest/iface.h"
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#include "nest/route.h"
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#include "nest/protocol.h"
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#include "filter/filter.h"
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#include "lib/timer.h"
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#include "conf/conf.h"
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#include "lib/string.h"
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#include "unix.h"
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#include "krt.h"
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/*
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* Global resources
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*/
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pool *krt_pool;
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static linpool *krt_filter_lp;
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static list krt_proto_list;
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void
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krt_io_init(void)
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{
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krt_pool = rp_new(&root_pool, "Kernel Syncer");
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krt_filter_lp = lp_new(krt_pool, 4080);
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init_list(&krt_proto_list);
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krt_sys_io_init();
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}
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/*
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* Interfaces
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*/
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struct kif_proto *kif_proto;
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static struct kif_config *kif_cf;
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static timer *kif_scan_timer;
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static bird_clock_t kif_last_shot;
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static void
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kif_scan(timer *t)
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{
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struct kif_proto *p = t->data;
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KRT_TRACE(p, D_EVENTS, "Scanning interfaces");
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kif_last_shot = now;
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kif_do_scan(p);
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}
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static void
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kif_force_scan(void)
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{
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if (kif_proto && kif_last_shot + 2 < now)
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{
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kif_scan(kif_scan_timer);
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tm_start(kif_scan_timer, ((struct kif_config *) kif_proto->p.cf)->scan_time);
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}
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}
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void
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kif_request_scan(void)
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{
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if (kif_proto && kif_scan_timer->expires > now)
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tm_start(kif_scan_timer, 1);
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}
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static inline int
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prefer_addr(struct ifa *a, struct ifa *b)
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{
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int sa = a->scope > SCOPE_LINK;
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int sb = b->scope > SCOPE_LINK;
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if (sa < sb)
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return 0;
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else if (sa > sb)
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return 1;
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else
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return ipa_compare(a->ip, b->ip) < 0;
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}
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static inline struct ifa *
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find_preferred_ifa(struct iface *i, ip_addr prefix, ip_addr mask)
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{
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struct ifa *a, *b = NULL;
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WALK_LIST(a, i->addrs)
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{
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if (!(a->flags & IA_SECONDARY) &&
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ipa_equal(ipa_and(a->ip, mask), prefix) &&
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(!b || prefer_addr(a, b)))
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b = a;
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}
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return b;
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}
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struct ifa *
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kif_choose_primary(struct iface *i)
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{
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struct kif_config *cf = (struct kif_config *) (kif_proto->p.cf);
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struct kif_primary_item *it;
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struct ifa *a;
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WALK_LIST(it, cf->primary)
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{
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if (!it->pattern || patmatch(it->pattern, i->name))
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if (a = find_preferred_ifa(i, it->prefix, ipa_mkmask(it->pxlen)))
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return a;
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}
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if (a = kif_get_primary_ip(i))
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return a;
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return find_preferred_ifa(i, IPA_NONE, IPA_NONE);
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}
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static struct proto *
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kif_init(struct proto_config *c)
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{
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struct kif_proto *p = proto_new(c, sizeof(struct kif_proto));
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kif_sys_init(p);
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return &p->p;
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}
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static int
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kif_start(struct proto *P)
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{
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struct kif_proto *p = (struct kif_proto *) P;
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kif_proto = p;
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kif_sys_start(p);
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/* Start periodic interface scanning */
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kif_scan_timer = tm_new(P->pool);
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kif_scan_timer->hook = kif_scan;
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kif_scan_timer->data = p;
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kif_scan_timer->recurrent = KIF_CF->scan_time;
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kif_scan(kif_scan_timer);
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tm_start(kif_scan_timer, KIF_CF->scan_time);
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return PS_UP;
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}
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static int
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kif_shutdown(struct proto *P)
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{
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struct kif_proto *p = (struct kif_proto *) P;
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tm_stop(kif_scan_timer);
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kif_sys_shutdown(p);
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kif_proto = NULL;
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return PS_DOWN;
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}
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static int
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kif_reconfigure(struct proto *p, struct proto_config *new)
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{
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struct kif_config *o = (struct kif_config *) p->cf;
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struct kif_config *n = (struct kif_config *) new;
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if (!kif_sys_reconfigure((struct kif_proto *) p, n, o))
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return 0;
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if (o->scan_time != n->scan_time)
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{
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tm_stop(kif_scan_timer);
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kif_scan_timer->recurrent = n->scan_time;
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kif_scan(kif_scan_timer);
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tm_start(kif_scan_timer, n->scan_time);
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}
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if (!EMPTY_LIST(o->primary) || !EMPTY_LIST(n->primary))
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{
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/* This is hack, we have to update a configuration
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* to the new value just now, because it is used
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* for recalculation of primary addresses.
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*/
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p->cf = new;
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ifa_recalc_all_primary_addresses();
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}
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return 1;
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}
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static void
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kif_preconfig(struct protocol *P UNUSED, struct config *c)
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{
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kif_cf = NULL;
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kif_sys_preconfig(c);
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}
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struct proto_config *
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kif_init_config(int class)
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{
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if (kif_cf)
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cf_error("Kernel device protocol already defined");
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kif_cf = (struct kif_config *) proto_config_new(&proto_unix_iface, class);
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kif_cf->scan_time = 60;
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init_list(&kif_cf->primary);
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kif_sys_init_config(kif_cf);
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return (struct proto_config *) kif_cf;
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}
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static void
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kif_copy_config(struct proto_config *dest, struct proto_config *src)
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{
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struct kif_config *d = (struct kif_config *) dest;
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struct kif_config *s = (struct kif_config *) src;
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/* Shallow copy of everything (just scan_time currently) */
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proto_copy_rest(dest, src, sizeof(struct kif_config));
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/* Copy primary addr list */
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cfg_copy_list(&d->primary, &s->primary, sizeof(struct kif_primary_item));
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/* Fix sysdep parts */
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kif_sys_copy_config(d, s);
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}
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struct protocol proto_unix_iface = {
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.name = "Device",
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.template = "device%d",
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.preference = DEF_PREF_DIRECT,
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.config_size = sizeof(struct kif_config),
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.preconfig = kif_preconfig,
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.init = kif_init,
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.start = kif_start,
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.shutdown = kif_shutdown,
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.reconfigure = kif_reconfigure,
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.copy_config = kif_copy_config
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};
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/*
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* Tracing of routes
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*/
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static inline void
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krt_trace_in(struct krt_proto *p, rte *e, char *msg)
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{
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if (p->p.debug & D_PACKETS)
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log(L_TRACE "%s: %I/%d: %s", p->p.name, e->net->n.prefix, e->net->n.pxlen, msg);
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}
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static inline void
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krt_trace_in_rl(struct tbf *f, struct krt_proto *p, rte *e, char *msg)
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{
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if (p->p.debug & D_PACKETS)
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log_rl(f, L_TRACE "%s: %I/%d: %s", p->p.name, e->net->n.prefix, e->net->n.pxlen, msg);
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}
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/*
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* Inherited Routes
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*/
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#ifdef KRT_ALLOW_LEARN
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static struct tbf rl_alien = TBF_DEFAULT_LOG_LIMITS;
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/*
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* krt_same_key() specifies what (aside from the net) is the key in
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* kernel routing tables. It should be OS-dependent, this is for
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* Linux. It is important for asynchronous alien updates, because a
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* positive update is implicitly a negative one for any old route with
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* the same key.
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*/
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static inline int
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krt_same_key(rte *a, rte *b)
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{
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return a->u.krt.metric == b->u.krt.metric;
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}
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static inline int
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krt_uptodate(rte *a, rte *b)
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{
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if (a->attrs != b->attrs)
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return 0;
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if (a->u.krt.proto != b->u.krt.proto)
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return 0;
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return 1;
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}
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static void
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krt_learn_announce_update(struct krt_proto *p, rte *e)
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{
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net *n = e->net;
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rta *aa = rta_clone(e->attrs);
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rte *ee = rte_get_temp(aa);
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net *nn = net_get(p->p.table, n->n.prefix, n->n.pxlen);
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ee->net = nn;
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ee->pflags = 0;
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ee->pref = p->p.preference;
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ee->u.krt = e->u.krt;
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rte_update(&p->p, nn, ee);
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}
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static void
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krt_learn_announce_delete(struct krt_proto *p, net *n)
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{
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n = net_find(p->p.table, n->n.prefix, n->n.pxlen);
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rte_update(&p->p, n, NULL);
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}
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/* Called when alien route is discovered during scan */
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static void
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krt_learn_scan(struct krt_proto *p, rte *e)
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{
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net *n0 = e->net;
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net *n = net_get(&p->krt_table, n0->n.prefix, n0->n.pxlen);
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rte *m, **mm;
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e->attrs = rta_lookup(e->attrs);
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for(mm=&n->routes; m = *mm; mm=&m->next)
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if (krt_same_key(m, e))
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break;
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if (m)
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{
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if (krt_uptodate(m, e))
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{
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krt_trace_in_rl(&rl_alien, p, e, "[alien] seen");
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rte_free(e);
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m->u.krt.seen = 1;
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}
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else
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{
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krt_trace_in(p, e, "[alien] updated");
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*mm = m->next;
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rte_free(m);
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m = NULL;
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}
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}
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else
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krt_trace_in(p, e, "[alien] created");
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if (!m)
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{
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e->next = n->routes;
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n->routes = e;
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e->u.krt.seen = 1;
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}
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}
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static void
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krt_learn_prune(struct krt_proto *p)
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{
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struct fib *fib = &p->krt_table.fib;
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struct fib_iterator fit;
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KRT_TRACE(p, D_EVENTS, "Pruning inherited routes");
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FIB_ITERATE_INIT(&fit, fib);
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again:
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FIB_ITERATE_START(fib, &fit, f)
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{
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net *n = (net *) f;
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rte *e, **ee, *best, **pbest, *old_best;
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/*
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* Note that old_best may be NULL even if there was an old best route in
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* the previous step, because it might be replaced in krt_learn_scan().
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* But in that case there is a new valid best route.
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*/
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old_best = NULL;
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best = NULL;
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pbest = NULL;
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ee = &n->routes;
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while (e = *ee)
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{
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if (e->u.krt.best)
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old_best = e;
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if (!e->u.krt.seen)
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{
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*ee = e->next;
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rte_free(e);
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continue;
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}
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if (!best || best->u.krt.metric > e->u.krt.metric)
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{
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best = e;
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pbest = ee;
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}
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e->u.krt.seen = 0;
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e->u.krt.best = 0;
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ee = &e->next;
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}
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if (!n->routes)
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{
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DBG("%I/%d: deleting\n", n->n.prefix, n->n.pxlen);
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if (old_best)
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krt_learn_announce_delete(p, n);
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FIB_ITERATE_PUT(&fit, f);
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fib_delete(fib, f);
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goto again;
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}
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best->u.krt.best = 1;
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*pbest = best->next;
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best->next = n->routes;
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n->routes = best;
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if ((best != old_best) || p->reload)
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{
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DBG("%I/%d: announcing (metric=%d)\n", n->n.prefix, n->n.pxlen, best->u.krt.metric);
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krt_learn_announce_update(p, best);
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}
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else
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DBG("%I/%d: uptodate (metric=%d)\n", n->n.prefix, n->n.pxlen, best->u.krt.metric);
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}
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FIB_ITERATE_END(f);
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p->reload = 0;
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}
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static void
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krt_learn_async(struct krt_proto *p, rte *e, int new)
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{
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net *n0 = e->net;
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net *n = net_get(&p->krt_table, n0->n.prefix, n0->n.pxlen);
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rte *g, **gg, *best, **bestp, *old_best;
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e->attrs = rta_lookup(e->attrs);
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old_best = n->routes;
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for(gg=&n->routes; g = *gg; gg = &g->next)
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if (krt_same_key(g, e))
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break;
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if (new)
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{
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if (g)
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{
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if (krt_uptodate(g, e))
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{
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krt_trace_in(p, e, "[alien async] same");
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rte_free(e);
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return;
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}
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krt_trace_in(p, e, "[alien async] updated");
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*gg = g->next;
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rte_free(g);
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}
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else
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krt_trace_in(p, e, "[alien async] created");
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e->next = n->routes;
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n->routes = e;
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}
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else if (!g)
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{
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krt_trace_in(p, e, "[alien async] delete failed");
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rte_free(e);
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return;
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}
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else
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{
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krt_trace_in(p, e, "[alien async] removed");
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*gg = g->next;
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rte_free(e);
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rte_free(g);
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}
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best = n->routes;
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bestp = &n->routes;
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for(gg=&n->routes; g=*gg; gg=&g->next)
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|
{
|
|
if (best->u.krt.metric > g->u.krt.metric)
|
|
{
|
|
best = g;
|
|
bestp = gg;
|
|
}
|
|
|
|
g->u.krt.best = 0;
|
|
}
|
|
|
|
if (best)
|
|
{
|
|
best->u.krt.best = 1;
|
|
*bestp = best->next;
|
|
best->next = n->routes;
|
|
n->routes = best;
|
|
}
|
|
|
|
if (best != old_best)
|
|
{
|
|
DBG("krt_learn_async: distributing change\n");
|
|
if (best)
|
|
krt_learn_announce_update(p, best);
|
|
else
|
|
krt_learn_announce_delete(p, n);
|
|
}
|
|
}
|
|
|
|
static void
|
|
krt_learn_init(struct krt_proto *p)
|
|
{
|
|
if (KRT_CF->learn)
|
|
rt_setup(p->p.pool, &p->krt_table, "Inherited", NULL);
|
|
}
|
|
|
|
static void
|
|
krt_dump(struct proto *P)
|
|
{
|
|
struct krt_proto *p = (struct krt_proto *) P;
|
|
|
|
if (!KRT_CF->learn)
|
|
return;
|
|
debug("KRT: Table of inheritable routes\n");
|
|
rt_dump(&p->krt_table);
|
|
}
|
|
|
|
static void
|
|
krt_dump_attrs(rte *e)
|
|
{
|
|
debug(" [m=%d,p=%d]", e->u.krt.metric, e->u.krt.proto);
|
|
}
|
|
|
|
#endif
|
|
|
|
/*
|
|
* Routes
|
|
*/
|
|
|
|
static void
|
|
krt_flush_routes(struct krt_proto *p)
|
|
{
|
|
struct rtable *t = p->p.table;
|
|
|
|
KRT_TRACE(p, D_EVENTS, "Flushing kernel routes");
|
|
FIB_WALK(&t->fib, f)
|
|
{
|
|
net *n = (net *) f;
|
|
rte *e = n->routes;
|
|
if (rte_is_valid(e) && (n->n.flags & KRF_INSTALLED))
|
|
{
|
|
/* FIXME: this does not work if gw is changed in export filter */
|
|
krt_replace_rte(p, e->net, NULL, e, NULL);
|
|
n->n.flags &= ~KRF_INSTALLED;
|
|
}
|
|
}
|
|
FIB_WALK_END;
|
|
}
|
|
|
|
static struct rte *
|
|
krt_export_net(struct krt_proto *p, net *net, rte **rt_free, ea_list **tmpa)
|
|
{
|
|
struct announce_hook *ah = p->p.main_ahook;
|
|
struct filter *filter = ah->out_filter;
|
|
rte *rt;
|
|
|
|
if (p->p.accept_ra_types == RA_MERGED)
|
|
return rt_export_merged(ah, net, rt_free, tmpa, krt_filter_lp, 1);
|
|
|
|
rt = net->routes;
|
|
*rt_free = NULL;
|
|
|
|
if (!rte_is_valid(rt))
|
|
return NULL;
|
|
|
|
if (filter == FILTER_REJECT)
|
|
return NULL;
|
|
|
|
struct proto *src = rt->attrs->src->proto;
|
|
*tmpa = src->make_tmp_attrs ? src->make_tmp_attrs(rt, krt_filter_lp) : NULL;
|
|
|
|
/* We could run krt_import_control() here, but it is already handled by KRF_INSTALLED */
|
|
|
|
if (filter == FILTER_ACCEPT)
|
|
goto accept;
|
|
|
|
if (f_run(filter, &rt, tmpa, krt_filter_lp, FF_FORCE_TMPATTR | FF_SILENT) > F_ACCEPT)
|
|
goto reject;
|
|
|
|
|
|
accept:
|
|
if (rt != net->routes)
|
|
*rt_free = rt;
|
|
return rt;
|
|
|
|
reject:
|
|
if (rt != net->routes)
|
|
rte_free(rt);
|
|
return NULL;
|
|
}
|
|
|
|
static int
|
|
krt_same_dest(rte *k, rte *e)
|
|
{
|
|
rta *ka = k->attrs, *ea = e->attrs;
|
|
|
|
if (ka->dest != ea->dest)
|
|
return 0;
|
|
switch (ka->dest)
|
|
{
|
|
case RTD_ROUTER:
|
|
return ipa_equal(ka->gw, ea->gw);
|
|
case RTD_DEVICE:
|
|
return !strcmp(ka->iface->name, ea->iface->name);
|
|
case RTD_MULTIPATH:
|
|
return mpnh_same(ka->nexthops, ea->nexthops);
|
|
default:
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This gets called back when the low-level scanning code discovers a route.
|
|
* We expect that the route is a temporary rte and its attributes are uncached.
|
|
*/
|
|
|
|
void
|
|
krt_got_route(struct krt_proto *p, rte *e)
|
|
{
|
|
net *net = e->net;
|
|
int verdict;
|
|
|
|
#ifdef KRT_ALLOW_LEARN
|
|
switch (e->u.krt.src)
|
|
{
|
|
case KRT_SRC_KERNEL:
|
|
verdict = KRF_IGNORE;
|
|
goto sentenced;
|
|
|
|
case KRT_SRC_REDIRECT:
|
|
verdict = KRF_DELETE;
|
|
goto sentenced;
|
|
|
|
case KRT_SRC_ALIEN:
|
|
if (KRT_CF->learn)
|
|
krt_learn_scan(p, e);
|
|
else
|
|
{
|
|
krt_trace_in_rl(&rl_alien, p, e, "[alien] ignored");
|
|
rte_free(e);
|
|
}
|
|
return;
|
|
}
|
|
#endif
|
|
/* The rest is for KRT_SRC_BIRD (or KRT_SRC_UNKNOWN) */
|
|
|
|
if (net->n.flags & KRF_VERDICT_MASK)
|
|
{
|
|
/* Route to this destination was already seen. Strange, but it happens... */
|
|
krt_trace_in(p, e, "already seen");
|
|
rte_free(e);
|
|
return;
|
|
}
|
|
|
|
if (!p->ready)
|
|
{
|
|
/* We wait for the initial feed to have correct KRF_INSTALLED flag */
|
|
verdict = KRF_IGNORE;
|
|
goto sentenced;
|
|
}
|
|
|
|
if (net->n.flags & KRF_INSTALLED)
|
|
{
|
|
rte *new, *rt_free;
|
|
ea_list *tmpa;
|
|
|
|
new = krt_export_net(p, net, &rt_free, &tmpa);
|
|
|
|
/* TODO: There also may be changes in route eattrs, we ignore that for now. */
|
|
|
|
if (!new)
|
|
verdict = KRF_DELETE;
|
|
else if ((net->n.flags & KRF_SYNC_ERROR) || !krt_same_dest(e, new))
|
|
verdict = KRF_UPDATE;
|
|
else
|
|
verdict = KRF_SEEN;
|
|
|
|
if (rt_free)
|
|
rte_free(rt_free);
|
|
|
|
lp_flush(krt_filter_lp);
|
|
}
|
|
else
|
|
verdict = KRF_DELETE;
|
|
|
|
sentenced:
|
|
krt_trace_in(p, e, ((char *[]) { "?", "seen", "will be updated", "will be removed", "ignored" }) [verdict]);
|
|
net->n.flags = (net->n.flags & ~KRF_VERDICT_MASK) | verdict;
|
|
if (verdict == KRF_UPDATE || verdict == KRF_DELETE)
|
|
{
|
|
/* Get a cached copy of attributes and temporarily link the route */
|
|
rta *a = e->attrs;
|
|
a->source = RTS_DUMMY;
|
|
e->attrs = rta_lookup(a);
|
|
e->next = net->routes;
|
|
net->routes = e;
|
|
}
|
|
else
|
|
rte_free(e);
|
|
}
|
|
|
|
static void
|
|
krt_prune(struct krt_proto *p)
|
|
{
|
|
struct rtable *t = p->p.table;
|
|
|
|
KRT_TRACE(p, D_EVENTS, "Pruning table %s", t->name);
|
|
FIB_WALK(&t->fib, f)
|
|
{
|
|
net *n = (net *) f;
|
|
int verdict = f->flags & KRF_VERDICT_MASK;
|
|
rte *new, *old, *rt_free = NULL;
|
|
ea_list *tmpa = NULL;
|
|
|
|
if (verdict == KRF_UPDATE || verdict == KRF_DELETE)
|
|
{
|
|
/* Get a dummy route from krt_got_route() */
|
|
old = n->routes;
|
|
n->routes = old->next;
|
|
}
|
|
else
|
|
old = NULL;
|
|
|
|
if (verdict == KRF_CREATE || verdict == KRF_UPDATE)
|
|
{
|
|
/* We have to run export filter to get proper 'new' route */
|
|
new = krt_export_net(p, n, &rt_free, &tmpa);
|
|
|
|
if (!new)
|
|
verdict = (verdict == KRF_CREATE) ? KRF_IGNORE : KRF_DELETE;
|
|
else
|
|
tmpa = ea_append(tmpa, new->attrs->eattrs);
|
|
}
|
|
else
|
|
new = NULL;
|
|
|
|
switch (verdict)
|
|
{
|
|
case KRF_CREATE:
|
|
if (new && (f->flags & KRF_INSTALLED))
|
|
{
|
|
krt_trace_in(p, new, "reinstalling");
|
|
krt_replace_rte(p, n, new, NULL, tmpa);
|
|
}
|
|
break;
|
|
case KRF_SEEN:
|
|
case KRF_IGNORE:
|
|
/* Nothing happens */
|
|
break;
|
|
case KRF_UPDATE:
|
|
krt_trace_in(p, new, "updating");
|
|
krt_replace_rte(p, n, new, old, tmpa);
|
|
break;
|
|
case KRF_DELETE:
|
|
krt_trace_in(p, old, "deleting");
|
|
krt_replace_rte(p, n, NULL, old, NULL);
|
|
break;
|
|
default:
|
|
bug("krt_prune: invalid route status");
|
|
}
|
|
|
|
if (old)
|
|
rte_free(old);
|
|
if (rt_free)
|
|
rte_free(rt_free);
|
|
lp_flush(krt_filter_lp);
|
|
f->flags &= ~KRF_VERDICT_MASK;
|
|
}
|
|
FIB_WALK_END;
|
|
|
|
#ifdef KRT_ALLOW_LEARN
|
|
if (KRT_CF->learn)
|
|
krt_learn_prune(p);
|
|
#endif
|
|
|
|
if (p->ready)
|
|
p->initialized = 1;
|
|
}
|
|
|
|
void
|
|
krt_got_route_async(struct krt_proto *p, rte *e, int new)
|
|
{
|
|
net *net = e->net;
|
|
|
|
switch (e->u.krt.src)
|
|
{
|
|
case KRT_SRC_BIRD:
|
|
ASSERT(0); /* Should be filtered by the back end */
|
|
|
|
case KRT_SRC_REDIRECT:
|
|
if (new)
|
|
{
|
|
krt_trace_in(p, e, "[redirect] deleting");
|
|
krt_replace_rte(p, net, NULL, e, NULL);
|
|
}
|
|
/* If !new, it is probably echo of our deletion */
|
|
break;
|
|
|
|
#ifdef KRT_ALLOW_LEARN
|
|
case KRT_SRC_ALIEN:
|
|
if (KRT_CF->learn)
|
|
{
|
|
krt_learn_async(p, e, new);
|
|
return;
|
|
}
|
|
#endif
|
|
}
|
|
rte_free(e);
|
|
}
|
|
|
|
/*
|
|
* Periodic scanning
|
|
*/
|
|
|
|
|
|
#ifdef CONFIG_ALL_TABLES_AT_ONCE
|
|
|
|
static timer *krt_scan_timer;
|
|
static int krt_scan_count;
|
|
|
|
static void
|
|
krt_scan(timer *t UNUSED)
|
|
{
|
|
struct krt_proto *p;
|
|
|
|
kif_force_scan();
|
|
|
|
/* We need some node to decide whether to print the debug messages or not */
|
|
p = SKIP_BACK(struct krt_proto, krt_node, HEAD(krt_proto_list));
|
|
KRT_TRACE(p, D_EVENTS, "Scanning routing table");
|
|
|
|
krt_do_scan(NULL);
|
|
|
|
void *q;
|
|
WALK_LIST(q, krt_proto_list)
|
|
{
|
|
p = SKIP_BACK(struct krt_proto, krt_node, q);
|
|
krt_prune(p);
|
|
}
|
|
}
|
|
|
|
static void
|
|
krt_scan_timer_start(struct krt_proto *p)
|
|
{
|
|
if (!krt_scan_count)
|
|
krt_scan_timer = tm_new_set(krt_pool, krt_scan, NULL, 0, KRT_CF->scan_time);
|
|
|
|
krt_scan_count++;
|
|
|
|
tm_start(krt_scan_timer, 1);
|
|
}
|
|
|
|
static void
|
|
krt_scan_timer_stop(struct krt_proto *p UNUSED)
|
|
{
|
|
krt_scan_count--;
|
|
|
|
if (!krt_scan_count)
|
|
{
|
|
rfree(krt_scan_timer);
|
|
krt_scan_timer = NULL;
|
|
}
|
|
}
|
|
|
|
static void
|
|
krt_scan_timer_kick(struct krt_proto *p UNUSED)
|
|
{
|
|
tm_start(krt_scan_timer, 0);
|
|
}
|
|
|
|
#else
|
|
|
|
static void
|
|
krt_scan(timer *t)
|
|
{
|
|
struct krt_proto *p = t->data;
|
|
|
|
kif_force_scan();
|
|
|
|
KRT_TRACE(p, D_EVENTS, "Scanning routing table");
|
|
krt_do_scan(p);
|
|
krt_prune(p);
|
|
}
|
|
|
|
static void
|
|
krt_scan_timer_start(struct krt_proto *p)
|
|
{
|
|
p->scan_timer = tm_new_set(p->p.pool, krt_scan, p, 0, KRT_CF->scan_time);
|
|
tm_start(p->scan_timer, 1);
|
|
}
|
|
|
|
static void
|
|
krt_scan_timer_stop(struct krt_proto *p)
|
|
{
|
|
tm_stop(p->scan_timer);
|
|
}
|
|
|
|
static void
|
|
krt_scan_timer_kick(struct krt_proto *p)
|
|
{
|
|
tm_start(p->scan_timer, 0);
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
/*
|
|
* Updates
|
|
*/
|
|
|
|
static struct ea_list *
|
|
krt_make_tmp_attrs(rte *rt, struct linpool *pool)
|
|
{
|
|
struct ea_list *l = lp_alloc(pool, sizeof(struct ea_list) + 2 * sizeof(eattr));
|
|
|
|
l->next = NULL;
|
|
l->flags = EALF_SORTED;
|
|
l->count = 2;
|
|
|
|
l->attrs[0].id = EA_KRT_SOURCE;
|
|
l->attrs[0].flags = 0;
|
|
l->attrs[0].type = EAF_TYPE_INT | EAF_TEMP;
|
|
l->attrs[0].u.data = rt->u.krt.proto;
|
|
|
|
l->attrs[1].id = EA_KRT_METRIC;
|
|
l->attrs[1].flags = 0;
|
|
l->attrs[1].type = EAF_TYPE_INT | EAF_TEMP;
|
|
l->attrs[1].u.data = rt->u.krt.metric;
|
|
|
|
return l;
|
|
}
|
|
|
|
static void
|
|
krt_store_tmp_attrs(rte *rt, struct ea_list *attrs)
|
|
{
|
|
/* EA_KRT_SOURCE is read-only */
|
|
rt->u.krt.metric = ea_get_int(attrs, EA_KRT_METRIC, 0);
|
|
}
|
|
|
|
static int
|
|
krt_import_control(struct proto *P, rte **new, ea_list **attrs UNUSED, struct linpool *pool UNUSED)
|
|
{
|
|
struct krt_proto *p = (struct krt_proto *) P;
|
|
rte *e = *new;
|
|
|
|
if (e->attrs->src->proto == P)
|
|
{
|
|
#ifdef CONFIG_SINGLE_ROUTE
|
|
/*
|
|
* Implicit withdraw - when the imported kernel route becomes the best one,
|
|
* we know that the previous one exported to the kernel was already removed,
|
|
* but if we processed the update as usual, we would send withdraw to the
|
|
* kernel, which would remove the new imported route instead.
|
|
*
|
|
* We will remove KRT_INSTALLED flag, which stops such withdraw to be
|
|
* processed in krt_rt_notify() and krt_replace_rte().
|
|
*/
|
|
if (e == e->net->routes)
|
|
e->net->n.flags &= ~KRF_INSTALLED;
|
|
#endif
|
|
return -1;
|
|
}
|
|
|
|
if (!KRT_CF->devroutes &&
|
|
(e->attrs->dest == RTD_DEVICE) &&
|
|
(e->attrs->source != RTS_STATIC_DEVICE))
|
|
return -1;
|
|
|
|
if (!krt_capable(e))
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
krt_rt_notify(struct proto *P, struct rtable *table UNUSED, net *net,
|
|
rte *new, rte *old, struct ea_list *eattrs)
|
|
{
|
|
struct krt_proto *p = (struct krt_proto *) P;
|
|
|
|
if (config->shutdown)
|
|
return;
|
|
if (!(net->n.flags & KRF_INSTALLED))
|
|
old = NULL;
|
|
if (new)
|
|
net->n.flags |= KRF_INSTALLED;
|
|
else
|
|
net->n.flags &= ~KRF_INSTALLED;
|
|
if (p->initialized) /* Before first scan we don't touch the routes */
|
|
krt_replace_rte(p, net, new, old, eattrs);
|
|
}
|
|
|
|
static void
|
|
krt_if_notify(struct proto *P, uint flags, struct iface *iface UNUSED)
|
|
{
|
|
struct krt_proto *p = (struct krt_proto *) P;
|
|
|
|
/*
|
|
* When interface went down, we should remove routes to it. In the ideal world,
|
|
* OS kernel would send us route removal notifications in such cases, but we
|
|
* cannot rely on it as it is often not true. E.g. Linux kernel removes related
|
|
* routes when an interface went down, but it does not notify userspace about
|
|
* that. To be sure, we just schedule a scan to ensure synchronization.
|
|
*/
|
|
|
|
if ((flags & IF_CHANGE_DOWN) && KRT_CF->learn)
|
|
krt_scan_timer_kick(p);
|
|
}
|
|
|
|
static int
|
|
krt_reload_routes(struct proto *P)
|
|
{
|
|
struct krt_proto *p = (struct krt_proto *) P;
|
|
|
|
/* Although we keep learned routes in krt_table, we rather schedule a scan */
|
|
|
|
if (KRT_CF->learn)
|
|
{
|
|
p->reload = 1;
|
|
krt_scan_timer_kick(p);
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static void
|
|
krt_feed_end(struct proto *P)
|
|
{
|
|
struct krt_proto *p = (struct krt_proto *) P;
|
|
|
|
p->ready = 1;
|
|
krt_scan_timer_kick(p);
|
|
}
|
|
|
|
|
|
static int
|
|
krt_rte_same(rte *a, rte *b)
|
|
{
|
|
/* src is always KRT_SRC_ALIEN and type is irrelevant */
|
|
return (a->u.krt.proto == b->u.krt.proto) && (a->u.krt.metric == b->u.krt.metric);
|
|
}
|
|
|
|
|
|
/*
|
|
* Protocol glue
|
|
*/
|
|
|
|
struct krt_config *krt_cf;
|
|
|
|
static struct proto *
|
|
krt_init(struct proto_config *C)
|
|
{
|
|
struct krt_proto *p = proto_new(C, sizeof(struct krt_proto));
|
|
struct krt_config *c = (struct krt_config *) C;
|
|
|
|
p->p.accept_ra_types = c->merge_paths ? RA_MERGED : RA_OPTIMAL;
|
|
p->p.merge_limit = c->merge_paths;
|
|
p->p.import_control = krt_import_control;
|
|
p->p.rt_notify = krt_rt_notify;
|
|
p->p.if_notify = krt_if_notify;
|
|
p->p.reload_routes = krt_reload_routes;
|
|
p->p.feed_end = krt_feed_end;
|
|
p->p.make_tmp_attrs = krt_make_tmp_attrs;
|
|
p->p.store_tmp_attrs = krt_store_tmp_attrs;
|
|
p->p.rte_same = krt_rte_same;
|
|
|
|
krt_sys_init(p);
|
|
return &p->p;
|
|
}
|
|
|
|
static int
|
|
krt_start(struct proto *P)
|
|
{
|
|
struct krt_proto *p = (struct krt_proto *) P;
|
|
|
|
add_tail(&krt_proto_list, &p->krt_node);
|
|
|
|
#ifdef KRT_ALLOW_LEARN
|
|
krt_learn_init(p);
|
|
#endif
|
|
|
|
if (!krt_sys_start(p))
|
|
{
|
|
rem_node(&p->krt_node);
|
|
return PS_START;
|
|
}
|
|
|
|
krt_scan_timer_start(p);
|
|
|
|
if (P->gr_recovery && KRT_CF->graceful_restart)
|
|
P->gr_wait = 1;
|
|
|
|
return PS_UP;
|
|
}
|
|
|
|
static int
|
|
krt_shutdown(struct proto *P)
|
|
{
|
|
struct krt_proto *p = (struct krt_proto *) P;
|
|
|
|
krt_scan_timer_stop(p);
|
|
|
|
/* FIXME we should flush routes even when persist during reconfiguration */
|
|
if (p->initialized && !KRT_CF->persist)
|
|
krt_flush_routes(p);
|
|
|
|
p->ready = 0;
|
|
p->initialized = 0;
|
|
|
|
if (p->p.proto_state == PS_START)
|
|
return PS_DOWN;
|
|
|
|
krt_sys_shutdown(p);
|
|
rem_node(&p->krt_node);
|
|
|
|
return PS_DOWN;
|
|
}
|
|
|
|
static int
|
|
krt_reconfigure(struct proto *p, struct proto_config *new)
|
|
{
|
|
struct krt_config *o = (struct krt_config *) p->cf;
|
|
struct krt_config *n = (struct krt_config *) new;
|
|
|
|
if (!krt_sys_reconfigure((struct krt_proto *) p, n, o))
|
|
return 0;
|
|
|
|
/* persist, graceful restart need not be the same */
|
|
return o->scan_time == n->scan_time && o->learn == n->learn &&
|
|
o->devroutes == n->devroutes && o->merge_paths == n->merge_paths;
|
|
}
|
|
|
|
static void
|
|
krt_preconfig(struct protocol *P UNUSED, struct config *c)
|
|
{
|
|
krt_cf = NULL;
|
|
krt_sys_preconfig(c);
|
|
}
|
|
|
|
static void
|
|
krt_postconfig(struct proto_config *C)
|
|
{
|
|
struct krt_config *c = (struct krt_config *) C;
|
|
|
|
#ifdef CONFIG_ALL_TABLES_AT_ONCE
|
|
if (krt_cf->scan_time != c->scan_time)
|
|
cf_error("All kernel syncers must use the same table scan interval");
|
|
#endif
|
|
|
|
if (C->table->krt_attached)
|
|
cf_error("Kernel syncer (%s) already attached to table %s", C->table->krt_attached->name, C->table->name);
|
|
C->table->krt_attached = C;
|
|
krt_sys_postconfig(c);
|
|
}
|
|
|
|
struct proto_config *
|
|
krt_init_config(int class)
|
|
{
|
|
#ifndef CONFIG_MULTIPLE_TABLES
|
|
if (krt_cf)
|
|
cf_error("Kernel protocol already defined");
|
|
#endif
|
|
|
|
krt_cf = (struct krt_config *) proto_config_new(&proto_unix_kernel, class);
|
|
krt_cf->scan_time = 60;
|
|
|
|
krt_sys_init_config(krt_cf);
|
|
return (struct proto_config *) krt_cf;
|
|
}
|
|
|
|
static void
|
|
krt_copy_config(struct proto_config *dest, struct proto_config *src)
|
|
{
|
|
struct krt_config *d = (struct krt_config *) dest;
|
|
struct krt_config *s = (struct krt_config *) src;
|
|
|
|
/* Shallow copy of everything */
|
|
proto_copy_rest(dest, src, sizeof(struct krt_config));
|
|
|
|
/* Fix sysdep parts */
|
|
krt_sys_copy_config(d, s);
|
|
}
|
|
|
|
static int
|
|
krt_get_attr(eattr *a, byte *buf, int buflen)
|
|
{
|
|
switch (a->id)
|
|
{
|
|
case EA_KRT_SOURCE:
|
|
bsprintf(buf, "source");
|
|
return GA_NAME;
|
|
|
|
case EA_KRT_METRIC:
|
|
bsprintf(buf, "metric");
|
|
return GA_NAME;
|
|
|
|
default:
|
|
return krt_sys_get_attr(a, buf, buflen);
|
|
}
|
|
}
|
|
|
|
|
|
struct protocol proto_unix_kernel = {
|
|
.name = "Kernel",
|
|
.template = "kernel%d",
|
|
.attr_class = EAP_KRT,
|
|
.preference = DEF_PREF_INHERITED,
|
|
.config_size = sizeof(struct krt_config),
|
|
.preconfig = krt_preconfig,
|
|
.postconfig = krt_postconfig,
|
|
.init = krt_init,
|
|
.start = krt_start,
|
|
.shutdown = krt_shutdown,
|
|
.reconfigure = krt_reconfigure,
|
|
.copy_config = krt_copy_config,
|
|
.get_attr = krt_get_attr,
|
|
#ifdef KRT_ALLOW_LEARN
|
|
.dump = krt_dump,
|
|
.dump_attrs = krt_dump_attrs,
|
|
#endif
|
|
};
|