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bird/sysdep/bsd/krt-sock.c
Ondrej Zajicek (work) a9f7570c30 KRT: Fix route learn scan when route changed
When a kernel route changed, function krt_learn_scan() noticed that and
replaced the route in internal kernel FIB, but after that, function
krt_learn_prune() failed to propagate the new route to the nest, because
it confused the new route with the (removed) old best route and decided
that the best route did not changed.

Wow, the original code (and the bug) is almost 17 years old.
2016-05-03 09:25:37 +02:00

1101 lines
22 KiB
C

/*
* BIRD -- BSD Routing Table Syncing
*
* (c) 2004 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <net/route.h>
#include <net/if.h>
#include <net/if_dl.h>
#undef LOCAL_DEBUG
#include "nest/bird.h"
#include "nest/iface.h"
#include "nest/route.h"
#include "nest/protocol.h"
#include "nest/iface.h"
#include "lib/timer.h"
#include "lib/unix.h"
#include "lib/krt.h"
#include "lib/string.h"
#include "lib/socket.h"
/*
* There are significant differences in multiple tables support between BSD variants.
*
* OpenBSD has table_id field for routes in route socket protocol, therefore all
* tables could be managed by one kernel socket. FreeBSD lacks such field,
* therefore multiple sockets (locked to specific table using SO_SETFIB socket
* option) must be used.
*
* Both FreeBSD and OpenBSD uses separate scans for each table. In OpenBSD,
* table_id is specified explicitly as sysctl scan argument, while in FreeBSD it
* is handled implicitly by changing default table using setfib() syscall.
*
* KRT_SHARED_SOCKET - use shared kernel socked instead of one for each krt_proto
* KRT_USE_SETFIB_SCAN - use setfib() for sysctl() route scan
* KRT_USE_SETFIB_SOCK - use SO_SETFIB socket option for kernel sockets
* KRT_USE_SYSCTL_7 - use 7-th arg of sysctl() as table id for route scans
* KRT_USE_SYSCTL_NET_FIBS - use net.fibs sysctl() for dynamic max number of fibs
*/
#ifdef __FreeBSD__
#define KRT_MAX_TABLES 256
#define KRT_USE_SETFIB_SCAN
#define KRT_USE_SETFIB_SOCK
#define KRT_USE_SYSCTL_NET_FIBS
#endif
#ifdef __OpenBSD__
#define KRT_MAX_TABLES (RT_TABLEID_MAX+1)
#define KRT_SHARED_SOCKET
#define KRT_USE_SYSCTL_7
#endif
#ifndef KRT_MAX_TABLES
#define KRT_MAX_TABLES 1
#endif
/* Dynamic max number of tables */
int krt_max_tables;
#ifdef KRT_USE_SYSCTL_NET_FIBS
static int
krt_get_max_tables(void)
{
int fibs;
size_t fibs_len = sizeof(fibs);
if (sysctlbyname("net.fibs", &fibs, &fibs_len, NULL, 0) < 0)
{
log(L_WARN "KRT: unable to get max number of fib tables: %m");
return 1;
}
return MIN(fibs, KRT_MAX_TABLES);
}
#else
static int
krt_get_max_tables(void)
{
return KRT_MAX_TABLES;
}
#endif /* KRT_USE_SYSCTL_NET_FIBS */
/* setfib() syscall for FreeBSD scans */
#ifdef KRT_USE_SETFIB_SCAN
/*
static int krt_default_fib;
static int
krt_get_active_fib(void)
{
int fib;
size_t fib_len = sizeof(fib);
if (sysctlbyname("net.my_fibnum", &fib, &fib_len, NULL, 0) < 0)
{
log(L_WARN "KRT: unable to get active fib number: %m");
return 0;
}
return fib;
}
*/
extern int setfib(int fib);
#endif /* KRT_USE_SETFIB_SCAN */
/* table_id -> krt_proto map */
#ifdef KRT_SHARED_SOCKET
static struct krt_proto *krt_table_map[KRT_MAX_TABLES];
#endif
/* Route socket message processing */
int
krt_capable(rte *e)
{
rta *a = e->attrs;
return
a->cast == RTC_UNICAST &&
(a->dest == RTD_ROUTER
|| a->dest == RTD_DEVICE
#ifdef RTF_REJECT
|| a->dest == RTD_UNREACHABLE
#endif
#ifdef RTF_BLACKHOLE
|| a->dest == RTD_BLACKHOLE
#endif
);
}
#ifndef RTAX_MAX
#define RTAX_MAX 8
#endif
struct ks_msg
{
struct rt_msghdr rtm;
struct sockaddr_storage buf[RTAX_MAX];
};
#define ROUNDUP(a) \
((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
#define NEXTADDR(w, u) \
if (msg.rtm.rtm_addrs & (w)) {\
l = ROUNDUP(((struct sockaddr *)&(u))->sa_len);\
memmove(body, &(u), l); body += l;}
#define GETADDR(p, F) \
bzero(p, sizeof(*p));\
if ((addrs & (F)) && ((struct sockaddr *)body)->sa_len) {\
uint l = ROUNDUP(((struct sockaddr *)body)->sa_len);\
memcpy(p, body, (l > sizeof(*p) ? sizeof(*p) : l));\
body += l;}
static int
krt_send_route(struct krt_proto *p, int cmd, rte *e)
{
net *net = e->net;
rta *a = e->attrs;
static int msg_seq;
struct iface *j, *i = a->iface;
int l;
struct ks_msg msg;
char *body = (char *)msg.buf;
sockaddr gate, mask, dst;
ip_addr gw;
DBG("krt-sock: send %I/%d via %I\n", net->n.prefix, net->n.pxlen, a->gw);
bzero(&msg,sizeof (struct rt_msghdr));
msg.rtm.rtm_version = RTM_VERSION;
msg.rtm.rtm_type = cmd;
msg.rtm.rtm_seq = msg_seq++;
msg.rtm.rtm_addrs = RTA_DST;
msg.rtm.rtm_flags = RTF_UP | RTF_PROTO1;
if (net->n.pxlen == MAX_PREFIX_LENGTH)
msg.rtm.rtm_flags |= RTF_HOST;
else
msg.rtm.rtm_addrs |= RTA_NETMASK;
#ifdef KRT_SHARED_SOCKET
msg.rtm.rtm_tableid = KRT_CF->sys.table_id;
#endif
#ifdef RTF_REJECT
if(a->dest == RTD_UNREACHABLE)
msg.rtm.rtm_flags |= RTF_REJECT;
#endif
#ifdef RTF_BLACKHOLE
if(a->dest == RTD_BLACKHOLE)
msg.rtm.rtm_flags |= RTF_BLACKHOLE;
#endif
/* This is really very nasty, but I'm not able
* to add "(reject|blackhole)" route without
* gateway set
*/
if(!i)
{
i = HEAD(iface_list);
WALK_LIST(j, iface_list)
{
if (j->flags & IF_LOOPBACK)
{
i = j;
break;
}
}
}
gw = a->gw;
#ifdef IPV6
/* Embed interface ID to link-local address */
if (ipa_is_link_local(gw))
_I0(gw) = 0xfe800000 | (i->index & 0x0000ffff);
#endif
sockaddr_fill(&dst, BIRD_AF, net->n.prefix, NULL, 0);
sockaddr_fill(&mask, BIRD_AF, ipa_mkmask(net->n.pxlen), NULL, 0);
sockaddr_fill(&gate, BIRD_AF, gw, NULL, 0);
switch (a->dest)
{
case RTD_ROUTER:
msg.rtm.rtm_flags |= RTF_GATEWAY;
msg.rtm.rtm_addrs |= RTA_GATEWAY;
break;
#ifdef RTF_REJECT
case RTD_UNREACHABLE:
#endif
#ifdef RTF_BLACKHOLE
case RTD_BLACKHOLE:
#endif
case RTD_DEVICE:
if(i)
{
#ifdef RTF_CLONING
if (cmd == RTM_ADD && (i->flags & IF_MULTIACCESS) != IF_MULTIACCESS) /* PTP */
msg.rtm.rtm_flags |= RTF_CLONING;
#endif
if(!i->addr) {
log(L_ERR "KRT: interface %s has no IP addess", i->name);
return -1;
}
sockaddr_fill(&gate, BIRD_AF, i->addr->ip, NULL, 0);
msg.rtm.rtm_addrs |= RTA_GATEWAY;
}
break;
default:
bug("krt-sock: unknown flags, but not filtered");
}
msg.rtm.rtm_index = i->index;
NEXTADDR(RTA_DST, dst);
NEXTADDR(RTA_GATEWAY, gate);
NEXTADDR(RTA_NETMASK, mask);
l = body - (char *)&msg;
msg.rtm.rtm_msglen = l;
if ((l = write(p->sys.sk->fd, (char *)&msg, l)) < 0) {
log(L_ERR "KRT: Error sending route %I/%d to kernel: %m", net->n.prefix, net->n.pxlen);
return -1;
}
return 0;
}
void
krt_replace_rte(struct krt_proto *p, net *n, rte *new, rte *old,
struct ea_list *eattrs UNUSED)
{
int err = 0;
if (old)
krt_send_route(p, RTM_DELETE, old);
if (new)
err = krt_send_route(p, RTM_ADD, new);
if (err < 0)
n->n.flags |= KRF_SYNC_ERROR;
else
n->n.flags &= ~KRF_SYNC_ERROR;
}
#define SKIP(ARG...) do { DBG("KRT: Ignoring route - " ARG); return; } while(0)
static void
krt_read_route(struct ks_msg *msg, struct krt_proto *p, int scan)
{
/* p is NULL iff KRT_SHARED_SOCKET and !scan */
rte *e;
net *net;
sockaddr dst, gate, mask;
ip_addr idst, igate, imask;
void *body = (char *)msg->buf;
int new = (msg->rtm.rtm_type != RTM_DELETE);
char *errmsg = "KRT: Invalid route received";
int flags = msg->rtm.rtm_flags;
int addrs = msg->rtm.rtm_addrs;
int src;
byte src2;
if (!(flags & RTF_UP) && scan)
SKIP("not up in scan\n");
if (!(flags & RTF_DONE) && !scan)
SKIP("not done in async\n");
if (flags & RTF_LLINFO)
SKIP("link-local\n");
#ifdef KRT_SHARED_SOCKET
if (!scan)
{
int table_id = msg->rtm.rtm_tableid;
p = (table_id < KRT_MAX_TABLES) ? krt_table_map[table_id] : NULL;
if (!p)
SKIP("unknown table id %d\n", table_id);
}
#endif
GETADDR(&dst, RTA_DST);
GETADDR(&gate, RTA_GATEWAY);
GETADDR(&mask, RTA_NETMASK);
if (dst.sa.sa_family != BIRD_AF)
SKIP("invalid DST");
idst = ipa_from_sa(&dst);
imask = ipa_from_sa(&mask);
igate = (gate.sa.sa_family == BIRD_AF) ? ipa_from_sa(&gate) : IPA_NONE;
/* We do not test family for RTA_NETMASK, because BSD sends us
some strange values, but interpreting them as IPv4/IPv6 works */
int c = ipa_classify_net(idst);
if ((c < 0) || !(c & IADDR_HOST) || ((c & IADDR_SCOPE_MASK) <= SCOPE_LINK))
SKIP("strange class/scope\n");
int pxlen = (flags & RTF_HOST) ? MAX_PREFIX_LENGTH : ipa_masklen(imask);
if (pxlen < 0)
{ log(L_ERR "%s (%I) - netmask %I", errmsg, idst, imask); return; }
if ((flags & RTF_GATEWAY) && ipa_zero(igate))
{ log(L_ERR "%s (%I/%d) - missing gateway", errmsg, idst, pxlen); return; }
u32 self_mask = RTF_PROTO1;
u32 alien_mask = RTF_STATIC | RTF_PROTO1 | RTF_GATEWAY;
src2 = (flags & RTF_STATIC) ? 1 : 0;
src2 |= (flags & RTF_PROTO1) ? 2 : 0;
#ifdef RTF_PROTO2
alien_mask |= RTF_PROTO2;
src2 |= (flags & RTF_PROTO2) ? 4 : 0;
#endif
#ifdef RTF_PROTO3
alien_mask |= RTF_PROTO3;
src2 |= (flags & RTF_PROTO3) ? 8 : 0;
#endif
#ifdef RTF_REJECT
alien_mask |= RTF_REJECT;
#endif
#ifdef RTF_BLACKHOLE
alien_mask |= RTF_BLACKHOLE;
#endif
if (flags & (RTF_DYNAMIC | RTF_MODIFIED))
src = KRT_SRC_REDIRECT;
else if (flags & self_mask)
{
if (!scan)
SKIP("echo\n");
src = KRT_SRC_BIRD;
}
else if (flags & alien_mask)
src = KRT_SRC_ALIEN;
else
src = KRT_SRC_KERNEL;
net = net_get(p->p.table, idst, pxlen);
rta a = {
.src = p->p.main_source,
.source = RTS_INHERIT,
.scope = SCOPE_UNIVERSE,
.cast = RTC_UNICAST
};
/* reject/blackhole routes have also set RTF_GATEWAY,
we wil check them first. */
#ifdef RTF_REJECT
if(flags & RTF_REJECT) {
a.dest = RTD_UNREACHABLE;
goto done;
}
#endif
#ifdef RTF_BLACKHOLE
if(flags & RTF_BLACKHOLE) {
a.dest = RTD_BLACKHOLE;
goto done;
}
#endif
a.iface = if_find_by_index(msg->rtm.rtm_index);
if (!a.iface)
{
log(L_ERR "KRT: Received route %I/%d with unknown ifindex %u",
net->n.prefix, net->n.pxlen, msg->rtm.rtm_index);
return;
}
if (flags & RTF_GATEWAY)
{
neighbor *ng;
a.dest = RTD_ROUTER;
a.gw = igate;
#ifdef IPV6
/* Clean up embedded interface ID returned in link-local address */
if (ipa_is_link_local(a.gw))
_I0(a.gw) = 0xfe800000;
#endif
ng = neigh_find2(&p->p, &a.gw, a.iface, 0);
if (!ng || (ng->scope == SCOPE_HOST))
{
/* Ignore routes with next-hop 127.0.0.1, host routes with such
next-hop appear on OpenBSD for address aliases. */
if (ipa_classify(a.gw) == (IADDR_HOST | SCOPE_HOST))
return;
log(L_ERR "KRT: Received route %I/%d with strange next-hop %I",
net->n.prefix, net->n.pxlen, a.gw);
return;
}
}
else
a.dest = RTD_DEVICE;
done:
e = rte_get_temp(&a);
e->net = net;
e->u.krt.src = src;
e->u.krt.proto = src2;
e->u.krt.seen = 0;
e->u.krt.best = 0;
e->u.krt.metric = 0;
if (scan)
krt_got_route(p, e);
else
krt_got_route_async(p, e, new);
}
static void
krt_read_ifannounce(struct ks_msg *msg)
{
struct if_announcemsghdr *ifam = (struct if_announcemsghdr *)&msg->rtm;
if (ifam->ifan_what == IFAN_ARRIVAL)
{
/* Not enough info to create the iface, so we just trigger iface scan */
kif_request_scan();
}
else if (ifam->ifan_what == IFAN_DEPARTURE)
{
struct iface *iface = if_find_by_index(ifam->ifan_index);
/* Interface is destroyed */
if (!iface)
{
DBG("KRT: unknown interface (%s, #%d) going down. Ignoring\n", ifam->ifan_name, ifam->ifan_index);
return;
}
if_delete(iface);
}
DBG("KRT: IFANNOUNCE what: %d index %d name %s\n", ifam->ifan_what, ifam->ifan_index, ifam->ifan_name);
}
static void
krt_read_ifinfo(struct ks_msg *msg, int scan)
{
struct if_msghdr *ifm = (struct if_msghdr *)&msg->rtm;
void *body = (void *)(ifm + 1);
struct sockaddr_dl *dl = NULL;
uint i;
struct iface *iface = NULL, f = {};
int fl = ifm->ifm_flags;
int nlen = 0;
for (i = 1; i<=RTA_IFP; i <<= 1)
{
if (i & ifm->ifm_addrs)
{
if (i == RTA_IFP)
{
dl = (struct sockaddr_dl *)body;
break;
}
body += ROUNDUP(((struct sockaddr *)&(body))->sa_len);
}
}
if (dl && (dl->sdl_family != AF_LINK))
{
log(L_WARN "Ignoring strange IFINFO");
return;
}
if (dl)
nlen = MIN(sizeof(f.name)-1, dl->sdl_nlen);
/* Note that asynchronous IFINFO messages do not contain iface
name, so we have to found an existing iface by iface index */
iface = if_find_by_index(ifm->ifm_index);
if (!iface)
{
/* New interface */
if (!dl)
return; /* No interface name, ignoring */
memcpy(f.name, dl->sdl_data, nlen);
DBG("New interface '%s' found\n", f.name);
}
else if (dl && memcmp(iface->name, dl->sdl_data, nlen))
{
/* Interface renamed */
if_delete(iface);
memcpy(f.name, dl->sdl_data, nlen);
}
else
{
/* Old interface */
memcpy(f.name, iface->name, sizeof(f.name));
}
f.index = ifm->ifm_index;
f.mtu = ifm->ifm_data.ifi_mtu;
if (fl & IFF_UP)
f.flags |= IF_ADMIN_UP;
if (ifm->ifm_data.ifi_link_state != LINK_STATE_DOWN)
f.flags |= IF_LINK_UP; /* up or unknown */
if (fl & IFF_LOOPBACK) /* Loopback */
f.flags |= IF_MULTIACCESS | IF_LOOPBACK | IF_IGNORE;
else if (fl & IFF_POINTOPOINT) /* PtP */
f.flags |= IF_MULTICAST;
else if (fl & IFF_BROADCAST) /* Broadcast */
f.flags |= IF_MULTIACCESS | IF_BROADCAST | IF_MULTICAST;
else
f.flags |= IF_MULTIACCESS; /* NBMA */
iface = if_update(&f);
if (!scan)
if_end_partial_update(iface);
}
static void
krt_read_addr(struct ks_msg *msg, int scan)
{
struct ifa_msghdr *ifam = (struct ifa_msghdr *)&msg->rtm;
void *body = (void *)(ifam + 1);
sockaddr addr, mask, brd;
struct iface *iface = NULL;
struct ifa ifa;
struct sockaddr null;
ip_addr iaddr, imask, ibrd;
int addrs = ifam->ifam_addrs;
int scope, masklen = -1;
int new = (ifam->ifam_type == RTM_NEWADDR);
/* Strange messages with zero (invalid) ifindex appear on OpenBSD */
if (ifam->ifam_index == 0)
return;
if(!(iface = if_find_by_index(ifam->ifam_index)))
{
log(L_ERR "KIF: Received address message for unknown interface %d", ifam->ifam_index);
return;
}
GETADDR (&null, RTA_DST);
GETADDR (&null, RTA_GATEWAY);
GETADDR (&mask, RTA_NETMASK);
GETADDR (&null, RTA_GENMASK);
GETADDR (&null, RTA_IFP);
GETADDR (&addr, RTA_IFA);
GETADDR (&null, RTA_AUTHOR);
GETADDR (&brd, RTA_BRD);
/* Some other family address */
if (addr.sa.sa_family != BIRD_AF)
return;
iaddr = ipa_from_sa(&addr);
imask = ipa_from_sa(&mask);
ibrd = ipa_from_sa(&brd);
if ((masklen = ipa_masklen(imask)) < 0)
{
log(L_ERR "KIF: Invalid masklen %I for %s", imask, iface->name);
return;
}
#ifdef IPV6
/* Clean up embedded interface ID returned in link-local address */
if (ipa_is_link_local(iaddr))
_I0(iaddr) = 0xfe800000;
if (ipa_is_link_local(ibrd))
_I0(ibrd) = 0xfe800000;
#endif
bzero(&ifa, sizeof(ifa));
ifa.iface = iface;
ifa.ip = iaddr;
ifa.pxlen = masklen;
scope = ipa_classify(ifa.ip);
if (scope < 0)
{
log(L_ERR "KIF: Invalid interface address %I for %s", ifa.ip, iface->name);
return;
}
ifa.scope = scope & IADDR_SCOPE_MASK;
if (masklen < BITS_PER_IP_ADDRESS)
{
ifa.prefix = ipa_and(ifa.ip, ipa_mkmask(masklen));
if (masklen == (BITS_PER_IP_ADDRESS - 1))
ifa.opposite = ipa_opposite_m1(ifa.ip);
#ifndef IPV6
if (masklen == (BITS_PER_IP_ADDRESS - 2))
ifa.opposite = ipa_opposite_m2(ifa.ip);
#endif
if (iface->flags & IF_BROADCAST)
ifa.brd = ibrd;
if (!(iface->flags & IF_MULTIACCESS))
ifa.opposite = ibrd;
}
else if (!(iface->flags & IF_MULTIACCESS) && ipa_nonzero(ibrd))
{
ifa.prefix = ifa.opposite = ibrd;
ifa.flags |= IA_PEER;
}
else
{
ifa.prefix = ifa.ip;
ifa.flags |= IA_HOST;
}
if (new)
ifa_update(&ifa);
else
ifa_delete(&ifa);
if (!scan)
if_end_partial_update(iface);
}
static void
krt_read_msg(struct proto *p, struct ks_msg *msg, int scan)
{
/* p is NULL iff KRT_SHARED_SOCKET and !scan */
switch (msg->rtm.rtm_type)
{
case RTM_GET:
if(!scan) return;
case RTM_ADD:
case RTM_DELETE:
case RTM_CHANGE:
krt_read_route(msg, (struct krt_proto *)p, scan);
break;
case RTM_IFANNOUNCE:
krt_read_ifannounce(msg);
break;
case RTM_IFINFO:
krt_read_ifinfo(msg, scan);
break;
case RTM_NEWADDR:
case RTM_DELADDR:
krt_read_addr(msg, scan);
break;
default:
break;
}
}
/* Sysctl based scans */
static byte *krt_buffer;
static size_t krt_buflen, krt_bufmin;
static struct proto *krt_buffer_owner;
static byte *
krt_buffer_update(struct proto *p, size_t *needed)
{
size_t req = *needed;
if ((req > krt_buflen) ||
((p == krt_buffer_owner) && (req < krt_bufmin)))
{
/* min buflen is 32 kB, step is 8 kB, or 128 kB if > 1 MB */
size_t step = (req < 0x100000) ? 0x2000 : 0x20000;
krt_buflen = (req < 0x6000) ? 0x8000 : (req + step);
krt_bufmin = (req < 0x8000) ? 0 : (req - 2*step);
if (krt_buffer)
mb_free(krt_buffer);
krt_buffer = mb_alloc(krt_pool, krt_buflen);
krt_buffer_owner = p;
}
*needed = krt_buflen;
return krt_buffer;
}
static void
krt_buffer_release(struct proto *p)
{
if (p == krt_buffer_owner)
{
mb_free(krt_buffer);
krt_buffer = NULL;
krt_buflen = 0;
krt_buffer_owner = 0;
}
}
static void
krt_sysctl_scan(struct proto *p, int cmd, int table_id)
{
byte *buf, *next;
int mib[7], mcnt;
size_t needed;
struct ks_msg *m;
int retries = 3;
int rv;
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = BIRD_AF;
mib[4] = cmd;
mib[5] = 0;
mcnt = 6;
#ifdef KRT_USE_SYSCTL_7
if (table_id >= 0)
{
mib[6] = table_id;
mcnt = 7;
}
#endif
#ifdef KRT_USE_SETFIB_SCAN
if (table_id > 0)
if (setfib(table_id) < 0)
{
log(L_ERR "KRT: setfib(%d) failed: %m", table_id);
return;
}
#endif
try:
rv = sysctl(mib, mcnt, NULL, &needed, NULL, 0);
if (rv < 0)
{
/* OpenBSD returns EINVAL for not yet used tables */
if ((errno == EINVAL) && (table_id > 0))
goto exit;
log(L_ERR "KRT: Route scan estimate failed: %m");
goto exit;
}
/* The table is empty */
if (needed == 0)
goto exit;
buf = krt_buffer_update(p, &needed);
rv = sysctl(mib, mcnt, buf, &needed, NULL, 0);
if (rv < 0)
{
/* The buffer size changed since last sysctl ('needed' is not changed) */
if ((errno == ENOMEM) && retries--)
goto try;
log(L_ERR "KRT: Route scan failed: %m");
goto exit;
}
#ifdef KRT_USE_SETFIB_SCAN
if (table_id > 0)
if (setfib(0) < 0)
die("KRT: setfib(%d) failed: %m", 0);
#endif
/* Process received messages */
for (next = buf; next < (buf + needed); next += m->rtm.rtm_msglen)
{
m = (struct ks_msg *)next;
krt_read_msg(p, m, 1);
}
return;
exit:
krt_buffer_release(p);
#ifdef KRT_USE_SETFIB_SCAN
if (table_id > 0)
if (setfib(0) < 0)
die("KRT: setfib(%d) failed: %m", 0);
#endif
}
void
krt_do_scan(struct krt_proto *p)
{
krt_sysctl_scan(&p->p, NET_RT_DUMP, KRT_CF->sys.table_id);
}
void
kif_do_scan(struct kif_proto *p)
{
if_start_update();
krt_sysctl_scan(&p->p, NET_RT_IFLIST, -1);
if_end_update();
}
/* Kernel sockets */
static int
krt_sock_hook(sock *sk, int size UNUSED)
{
struct ks_msg msg;
int l = read(sk->fd, (char *)&msg, sizeof(msg));
if (l <= 0)
log(L_ERR "krt-sock: read failed");
else
krt_read_msg((struct proto *) sk->data, &msg, 0);
return 0;
}
static sock *
krt_sock_open(pool *pool, void *data, int table_id)
{
sock *sk;
int fd;
fd = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC);
if (fd < 0)
die("Cannot open kernel socket for routes");
#ifdef KRT_USE_SETFIB_SOCK
if (table_id > 0)
{
if (setsockopt(fd, SOL_SOCKET, SO_SETFIB, &table_id, sizeof(table_id)) < 0)
die("Cannot set FIB %d for kernel socket: %m", table_id);
}
#endif
sk = sk_new(pool);
sk->type = SK_MAGIC;
sk->rx_hook = krt_sock_hook;
sk->fd = fd;
sk->data = data;
if (sk_open(sk) < 0)
bug("krt-sock: sk_open failed");
return sk;
}
#ifdef KRT_SHARED_SOCKET
static sock *krt_sock;
static int krt_sock_count;
static void
krt_sock_open_shared(void)
{
if (!krt_sock_count)
krt_sock = krt_sock_open(krt_pool, NULL, -1);
krt_sock_count++;
}
static void
krt_sock_close_shared(void)
{
krt_sock_count--;
if (!krt_sock_count)
{
rfree(krt_sock);
krt_sock = NULL;
}
}
int
krt_sys_start(struct krt_proto *p)
{
krt_table_map[KRT_CF->sys.table_id] = p;
krt_sock_open_shared();
p->sys.sk = krt_sock;
return 1;
}
void
krt_sys_shutdown(struct krt_proto *p)
{
krt_sock_close_shared();
p->sys.sk = NULL;
krt_table_map[KRT_CF->sys.table_id] = NULL;
krt_buffer_release(&p->p);
}
#else
int
krt_sys_start(struct krt_proto *p)
{
p->sys.sk = krt_sock_open(p->p.pool, p, KRT_CF->sys.table_id);
return 1;
}
void
krt_sys_shutdown(struct krt_proto *p)
{
rfree(p->sys.sk);
p->sys.sk = NULL;
krt_buffer_release(&p->p);
}
#endif /* KRT_SHARED_SOCKET */
/* KRT configuration callbacks */
static u32 krt_table_cf[(KRT_MAX_TABLES+31) / 32];
int
krt_sys_reconfigure(struct krt_proto *p UNUSED, struct krt_config *n, struct krt_config *o)
{
return n->sys.table_id == o->sys.table_id;
}
void
krt_sys_preconfig(struct config *c UNUSED)
{
krt_max_tables = krt_get_max_tables();
bzero(&krt_table_cf, sizeof(krt_table_cf));
}
void
krt_sys_postconfig(struct krt_config *x)
{
u32 *tbl = krt_table_cf;
int id = x->sys.table_id;
if (tbl[id/32] & (1 << (id%32)))
cf_error("Multiple kernel syncers defined for table #%d", id);
tbl[id/32] |= (1 << (id%32));
}
void krt_sys_init_config(struct krt_config *c)
{
c->sys.table_id = 0; /* Default table */
}
void krt_sys_copy_config(struct krt_config *d, struct krt_config *s)
{
d->sys.table_id = s->sys.table_id;
}
/* KIF misc code */
void
kif_sys_start(struct kif_proto *p UNUSED)
{
}
void
kif_sys_shutdown(struct kif_proto *p)
{
krt_buffer_release(&p->p);
}
struct ifa *
kif_get_primary_ip(struct iface *i)
{
#ifndef IPV6
static int fd = -1;
if (fd < 0)
fd = socket(AF_INET, SOCK_DGRAM, 0);
struct ifreq ifr;
memset(&ifr, 0, sizeof(ifr));
strncpy(ifr.ifr_name, i->name, IFNAMSIZ);
int rv = ioctl(fd, SIOCGIFADDR, (char *) &ifr);
if (rv < 0)
return NULL;
ip_addr addr;
struct sockaddr_in *sin = (struct sockaddr_in *) &ifr.ifr_addr;
memcpy(&addr, &sin->sin_addr.s_addr, sizeof(ip_addr));
ipa_ntoh(addr);
struct ifa *a;
WALK_LIST(a, i->addrs)
{
if (ipa_equal(a->ip, addr))
return a;
}
#endif
return NULL;
}