You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
tdenetwork/krfb/srvloc/getifaddrs.cpp

262 lines
6.1 KiB

/* getifaddrs -- get names and addresses of all network interfaces
Copyright (C) 1999,2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA. */
/**
* 02-12-26, tim@tjansen.de: put in kde_ namespace, C++ fixes,
* included ifreq.h
* removed glibc dependencies
*/
#include "config.h"
#ifndef HAVE_GETIFADDRS
#include "getifaddrs.h"
#include <net/if.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <netinet/in.h>
#include <stdio.h>
#ifndef IF_NAMESIZE
#define IF_NAMESIZE IFNAMSIZ
#endif
#ifdef SIOCGIFCONF
#define old_siocgifconf 0
static inline void
__ifreq (struct ifreq **ifreqs, int *num_ifs, int sockfd)
{
int fd = sockfd;
struct ifconf ifc;
int rq_len;
int nifs;
# define RTQ_IFS 4
if (fd < 0)
fd = socket (AF_INET, SOCK_DGRAM, 0);
if (fd < 0)
{
*num_ifs = 0;
*ifreqs = NULL;
return;
}
ifc.ifc_buf = NULL;
/* We may be able to get the needed buffer size directly, rather than
guessing. */
if (! old_siocgifconf)
{
ifc.ifc_buf = NULL;
ifc.ifc_len = 0;
if (ioctl (fd, SIOCGIFCONF, &ifc) < 0 || ifc.ifc_len == 0)
{
rq_len = RTQ_IFS * sizeof (struct ifreq);
}
else
rq_len = ifc.ifc_len;
}
else
rq_len = RTQ_IFS * sizeof (struct ifreq);
/* Read all the interfaces out of the kernel. */
while (1)
{
ifc.ifc_len = rq_len;
ifc.ifc_buf = (char*) realloc (ifc.ifc_buf, ifc.ifc_len);
if (ifc.ifc_buf == NULL || ioctl (fd, SIOCGIFCONF, &ifc) < 0)
{
if (ifc.ifc_buf)
free (ifc.ifc_buf);
if (fd != sockfd)
close (fd);
*num_ifs = 0;
*ifreqs = NULL;
return;
}
if (!old_siocgifconf || ifc.ifc_len < rq_len)
break;
rq_len *= 2;
}
nifs = ifc.ifc_len / sizeof (struct ifreq);
if (fd != sockfd)
close (fd);
*num_ifs = nifs;
*ifreqs = (ifreq*)realloc (ifc.ifc_buf, nifs * sizeof (struct ifreq));
}
static inline struct ifreq *
__if_nextreq (struct ifreq *ifr)
{
return ifr + 1;
}
static inline void
__if_freereq (struct ifreq *ifreqs, int num_ifs)
{
free (ifreqs);
}
/* Create a linked list of `struct kde_ifaddrs' structures, one for each
network interface on the host machine. If successful, store the
list in *IFAP and return 0. On errors, return -1 and set `errno'. */
int
kde_getifaddrs (struct kde_ifaddrs **ifap)
{
/* This implementation handles only IPv4 interfaces.
The various ioctls below will only work on an AF_INET socket.
Some different mechanism entirely must be used for IPv6. */
int fd = socket (AF_INET, SOCK_DGRAM, 0);
struct ifreq *ifreqs;
int nifs;
if (fd < 0)
return -1;
__ifreq (&ifreqs, &nifs, fd);
if (ifreqs == NULL) /* XXX doesn't distinguish error vs none */
{
close (fd);
return -1;
}
/* Now we have the list of interfaces and each one's address.
Put it into the expected format and fill in the remaining details. */
if (nifs == 0)
*ifap = NULL;
else
{
struct Storage
{
struct kde_ifaddrs ia;
struct sockaddr addr, netmask, broadaddr;
char name[IF_NAMESIZE];
} *storage;
struct ifreq *ifr;
int i;
storage = (Storage*) malloc (nifs * sizeof storage[0]);
if (storage == NULL)
{
close (fd);
__if_freereq (ifreqs, nifs);
return -1;
}
i = 0;
ifr = ifreqs;
do
{
/* Fill in all pointers to the storage we've already allocated. */
storage[i].ia.ifa_next = &storage[i + 1].ia;
storage[i].ia.ifa_addr = &storage[i].addr;
storage[i].ia.ifa_netmask = &storage[i].netmask;
storage[i].ia.ifa_broadaddr = &storage[i].broadaddr; /* & dstaddr */
/* Now copy the information we already have from SIOCGIFCONF. */
storage[i].ia.ifa_name = strncpy (storage[i].name, ifr->ifr_name,
sizeof storage[i].name);
storage[i].addr = ifr->ifr_addr;
/* The SIOCGIFCONF call filled in only the name and address.
Now we must also ask for the other information we need. */
if (ioctl (fd, SIOCGIFFLAGS, ifr) < 0)
break;
storage[i].ia.ifa_flags = ifr->ifr_flags;
ifr->ifr_addr = storage[i].addr;
if (ioctl (fd, SIOCGIFNETMASK, ifr) < 0)
break;
storage[i].netmask = ifr->ifr_netmask;
if (ifr->ifr_flags & IFF_BROADCAST)
{
ifr->ifr_addr = storage[i].addr;
if (ioctl (fd, SIOCGIFBRDADDR, ifr) < 0)
break;
storage[i].broadaddr = ifr->ifr_broadaddr;
}
else if (ifr->ifr_flags & IFF_POINTOPOINT)
{
ifr->ifr_addr = storage[i].addr;
if (ioctl (fd, SIOCGIFDSTADDR, ifr) < 0)
break;
storage[i].broadaddr = ifr->ifr_dstaddr;
}
else
/* Just 'cause. */
memset (&storage[i].broadaddr, 0, sizeof storage[i].broadaddr);
storage[i].ia.ifa_data = NULL; /* Nothing here for now. */
ifr = __if_nextreq (ifr);
} while (++i < nifs);
if (i < nifs) /* Broke out early on error. */
{
close (fd);
free (storage);
__if_freereq (ifreqs, nifs);
return -1;
}
storage[i - 1].ia.ifa_next = NULL;
*ifap = &storage[0].ia;
close (fd);
__if_freereq (ifreqs, nifs);
}
return 0;
}
void
kde_freeifaddrs (struct kde_ifaddrs *ifa)
{
free (ifa);
}
#else
int kde_getifaddrs(struct kde_ifaddrs **) {
return 1;
}
void kde_freeifaddrs(struct kde_ifaddrs *) {
}
struct { } kde_ifaddrs;
#endif
#endif