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/*
* BIRD -- Unix Interface Scanning and Syncing
*
* (c) 1998--1999 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <errno.h>
#define LOCAL_DEBUG
#include "nest/bird.h"
#include "nest/iface.h"
#include "nest/route.h"
#include "nest/protocol.h"
#include "lib/timer.h"
#include "lib/krt.h"
#include "unix.h"
int if_scan_sock = -1;
static void
scan_ifs(struct ifreq *r, int cnt)
{
struct iface i, *pi;
struct ifa a;
char *err, *colon;
unsigned fl;
ip_addr netmask;
int l;
if_start_update();
for (cnt /= sizeof(struct ifreq); cnt; cnt--, r++)
{
int sec = 0;
bzero(&i, sizeof(i));
bzero(&a, sizeof(a));
DBG("%s\n", r->ifr_name);
if (colon = strchr(r->ifr_name, ':'))
{
/* It's an alias -- let's interpret it as a secondary interface address */
sec = 1;
*colon = 0;
}
strncpy(i.name, r->ifr_name, sizeof(i.name) - 1);
get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.ip, NULL);
if (ipa_nonzero(a.ip))
{
l = ipa_classify(a.ip);
if (l < 0 || !(l & IADDR_HOST))
{
log(L_ERR "%s: Invalid interface address", i.name);
a.ip = IPA_NONE;
}
else
{
a.scope = l & IADDR_SCOPE_MASK;
if (a.scope == SCOPE_HOST)
i.flags |= IF_LOOPBACK | IF_IGNORE;
}
}
if (ioctl(if_scan_sock, SIOCGIFFLAGS, r) < 0)
{
err = "SIOCGIFFLAGS";
faulty:
log(L_ERR "%s(%s): %m", err, i.name);
bad:
i.flags = (i.flags & ~IF_LINK_UP) | IF_ADMIN_DOWN;
continue;
}
fl = r->ifr_flags;
if (fl & IFF_UP)
i.flags |= IF_LINK_UP;
if (ioctl(if_scan_sock, SIOCGIFNETMASK, r) < 0)
{ err = "SIOCGIFNETMASK"; goto faulty; }
get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &netmask, NULL);
l = ipa_mklen(netmask);
if (l < 0 || l == 31)
{
log(L_ERR "%s: Invalid netmask", i.name);
goto bad;
}
a.pxlen = l;
if (fl & IFF_POINTOPOINT)
{
i.flags |= IF_UNNUMBERED;
a.pxlen = BITS_PER_IP_ADDRESS;
if (ioctl(if_scan_sock, SIOCGIFDSTADDR, r) < 0)
{ err = "SIOCGIFDSTADDR"; goto faulty; }
get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.opposite, NULL);
}
if (fl & IFF_LOOPBACK)
i.flags |= IF_LOOPBACK | IF_IGNORE;
if (1
#ifndef CONFIG_ALL_MULTICAST
&& (fl & IFF_MULTICAST)
#endif
#ifndef CONFIG_UNNUM_MULTICAST
&& !(i.flags & IF_UNNUMBERED)
#endif
)
i.flags |= IF_MULTICAST;
a.prefix = ipa_and(a.ip, ipa_mkmask(a.pxlen));
if (a.pxlen < 32)
{
a.brd = ipa_or(a.prefix, ipa_not(ipa_mkmask(a.pxlen)));
if (ipa_equal(a.ip, a.prefix) || ipa_equal(a.ip, a.brd))
{
log(L_ERR "%s: Using network or broadcast address for interface", i.name);
goto bad;
}
if (fl & IFF_BROADCAST)
i.flags |= IF_BROADCAST;
if (a.pxlen < 30)
i.flags |= IF_MULTIACCESS;
else
a.opposite = ipa_opposite(a.ip);
}
else
a.brd = a.opposite;
if (ioctl(if_scan_sock, SIOCGIFMTU, r) < 0)
{ err = "SIOCGIFMTU"; goto faulty; }
i.mtu = r->ifr_mtu;
#ifdef SIOCGIFINDEX
if (ioctl(if_scan_sock, SIOCGIFINDEX, r) >= 0)
i.index = r->ifr_ifindex;
else if (errno != -EINVAL)
DBG("SIOCGIFINDEX failed: %m\n");
else /* defined, but not supported by the kernel */
#endif
/*
* The kernel doesn't give us real ifindices, but we still need them
* at least for OSPF unnumbered links. So let's make them up ourselves.
*/
if (pi = if_find_by_name(i.name))
i.index = pi->index;
else
{
static int if_index_counter = 1;
i.index = if_index_counter++;
}
pi = NULL;
if (sec)
{
a.flags |= IA_SECONDARY;
pi = if_find_by_index(i.index);
}
if (!pi)
pi = if_update(&i);
a.iface = pi;
ifa_update(&a);
}
if_end_update();
}
void
krt_if_scan(struct kif_proto *p)
{
struct ifconf ic;
static int last_ifbuf_size = 4*sizeof(struct ifreq);
int res;
for(;;)
{
if (last_ifbuf_size)
{
struct ifreq *r = alloca(last_ifbuf_size);
ic.ifc_ifcu.ifcu_req = r;
ic.ifc_len = last_ifbuf_size;
res = ioctl(if_scan_sock, SIOCGIFCONF, &ic);
if (res < 0 && errno != EFAULT)
die("SIOCCGIFCONF: %m");
if (res >= 0 && ic.ifc_len < last_ifbuf_size)
{
scan_ifs(r, ic.ifc_len);
break;
}
}
#if 0
/*
* Linux 2.1 and higher supports this, but it's not needed since
* we prefer to use Netlink there anyway.
*/
ic.ifc_req = NULL;
ic.ifc_len = 999999999;
if (ioctl(if_scan_sock, SIOCGIFCONF, &ic) < 0)
die("SIOCIFCONF: %m");
ic.ifc_len += sizeof(struct ifreq);
if (last_ifbuf_size < ic.ifc_len)
{
last_ifbuf_size = ic.ifc_len;
DBG("Increased ifconf buffer size to %d\n", last_ifbuf_size);
}
#else
last_ifbuf_size *= 2;
DBG("Increased ifconf buffer size to %d\n", last_ifbuf_size);
#endif
}
}
void
krt_if_construct(struct kif_config *c)
{
}
void
krt_if_start(struct kif_proto *p)
{
}
void
krt_if_shutdown(struct kif_proto *p)
{
}
void
krt_if_io_init(void)
{
if_scan_sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
DBG("Using socket %d for interface and route scanning\n", if_scan_sock);
if (if_scan_sock < 0)
die("Cannot create scanning socket: %m");
}
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