minix/lib/libc/net/getifaddrs.c

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/* $NetBSD: getifaddrs.c,v 1.13 2010/11/05 16:23:56 pooka Exp $ */
/*
* Copyright (c) 1995, 1999
* Berkeley Software Design, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* BSDI getifaddrs.c,v 2.12 2000/02/23 14:51:59 dab Exp
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: getifaddrs.c,v 1.13 2010/11/05 16:23:56 pooka Exp $");
#endif /* LIBC_SCCS and not lint */
#ifndef RUMP_ACTION
#include "namespace.h"
#endif
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <sys/param.h>
#include <net/route.h>
#include <sys/sysctl.h>
#include <net/if_dl.h>
#include <assert.h>
#include <errno.h>
#include <ifaddrs.h>
#include <stdlib.h>
#include <string.h>
#if defined(__weak_alias) && !defined(RUMP_ACTION)
__weak_alias(getifaddrs,_getifaddrs)
__weak_alias(freeifaddrs,_freeifaddrs)
#endif
#ifdef RUMP_ACTION
#include <rump/rump_syscalls.h>
#define sysctl(a,b,c,d,e,f) rump_sys___sysctl(a,b,c,d,e,f)
#endif
#define SALIGN (sizeof(long) - 1)
#define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : (SALIGN + 1))
int
getifaddrs(struct ifaddrs **pif)
{
int icnt = 1;
int dcnt = 0;
int ncnt = 0;
int mib[6];
size_t needed;
char *buf;
char *next;
struct ifaddrs cif;
char *p, *p0;
struct rt_msghdr *rtm;
struct if_msghdr *ifm;
struct ifa_msghdr *ifam;
struct sockaddr *sa;
struct ifaddrs *ifa, *ift;
u_short idx = 0;
int i;
size_t len, alen;
char *data;
char *names;
_DIAGASSERT(pif != NULL);
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0; /* protocol */
mib[3] = 0; /* wildcard address family */
mib[4] = NET_RT_IFLIST;
mib[5] = 0; /* no flags */
if (sysctl(mib, __arraycount(mib), NULL, &needed, NULL, 0) < 0)
return (-1);
if ((buf = malloc(needed)) == NULL)
return (-1);
if (sysctl(mib, __arraycount(mib), buf, &needed, NULL, 0) < 0) {
free(buf);
return (-1);
}
for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
rtm = (struct rt_msghdr *)(void *)next;
if (rtm->rtm_version != RTM_VERSION)
continue;
switch (rtm->rtm_type) {
case RTM_IFINFO:
ifm = (struct if_msghdr *)(void *)rtm;
if (ifm->ifm_addrs & RTA_IFP) {
const struct sockaddr_dl *dl;
idx = ifm->ifm_index;
++icnt;
dl = (struct sockaddr_dl *)(void *)(ifm + 1);
dcnt += SA_RLEN((const struct sockaddr *)(const void *)dl) +
ALIGNBYTES;
dcnt += sizeof(ifm->ifm_data);
ncnt += dl->sdl_nlen + 1;
} else
idx = 0;
break;
case RTM_NEWADDR:
ifam = (struct ifa_msghdr *)(void *)rtm;
if (idx && ifam->ifam_index != idx)
abort(); /* this cannot happen */
#define RTA_MASKS (RTA_NETMASK | RTA_IFA | RTA_BRD)
if (idx == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0)
break;
p = (char *)(void *)(ifam + 1);
++icnt;
/* Scan to look for length of address */
alen = 0;
for (p0 = p, i = 0; i < RTAX_MAX; i++) {
if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
== 0)
continue;
sa = (struct sockaddr *)(void *)p;
len = SA_RLEN(sa);
if (i == RTAX_IFA) {
alen = len;
break;
}
p += len;
}
for (p = p0, i = 0; i < RTAX_MAX; i++) {
if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
== 0)
continue;
sa = (struct sockaddr *)(void *)p;
len = SA_RLEN(sa);
if (i == RTAX_NETMASK && sa->sa_len == 0)
dcnt += alen;
else
dcnt += len;
p += len;
}
break;
}
}
if (icnt + dcnt + ncnt == 1) {
*pif = NULL;
free(buf);
return (0);
}
data = malloc(sizeof(struct ifaddrs) * icnt + dcnt + ncnt);
if (data == NULL) {
free(buf);
return(-1);
}
ifa = (struct ifaddrs *)(void *)data;
data += sizeof(struct ifaddrs) * icnt;
names = data + dcnt;
memset(ifa, 0, sizeof(struct ifaddrs) * icnt);
ift = ifa;
idx = 0;
for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
rtm = (struct rt_msghdr *)(void *)next;
if (rtm->rtm_version != RTM_VERSION)
continue;
switch (rtm->rtm_type) {
case RTM_IFINFO:
ifm = (struct if_msghdr *)(void *)rtm;
if (ifm->ifm_addrs & RTA_IFP) {
const struct sockaddr_dl *dl;
idx = ifm->ifm_index;
dl = (struct sockaddr_dl *)(void *)(ifm + 1);
memset(&cif, 0, sizeof(cif));
cif.ifa_name = names;
cif.ifa_flags = (int)ifm->ifm_flags;
memcpy(names, dl->sdl_data,
(size_t)dl->sdl_nlen);
names[dl->sdl_nlen] = 0;
names += dl->sdl_nlen + 1;
cif.ifa_addr = (struct sockaddr *)(void *)data;
memcpy(data, dl, (size_t)dl->sdl_len);
data += SA_RLEN((const struct sockaddr *)(const void *)dl);
/* ifm_data needs to be aligned */
cif.ifa_data = data = (void *)ALIGN(data);
memcpy(data, &ifm->ifm_data, sizeof(ifm->ifm_data));
data += sizeof(ifm->ifm_data);
} else
idx = 0;
break;
case RTM_NEWADDR:
ifam = (struct ifa_msghdr *)(void *)rtm;
if (idx && ifam->ifam_index != idx)
abort(); /* this cannot happen */
if (idx == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0)
break;
ift->ifa_name = cif.ifa_name;
ift->ifa_flags = cif.ifa_flags;
ift->ifa_data = NULL;
p = (char *)(void *)(ifam + 1);
/* Scan to look for length of address */
alen = 0;
for (p0 = p, i = 0; i < RTAX_MAX; i++) {
if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
== 0)
continue;
sa = (struct sockaddr *)(void *)p;
len = SA_RLEN(sa);
if (i == RTAX_IFA) {
alen = len;
break;
}
p += len;
}
for (p = p0, i = 0; i < RTAX_MAX; i++) {
if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
== 0)
continue;
sa = (struct sockaddr *)(void *)p;
len = SA_RLEN(sa);
switch (i) {
case RTAX_IFA:
ift->ifa_addr =
(struct sockaddr *)(void *)data;
memcpy(data, p, len);
data += len;
if (ift->ifa_addr->sa_family == AF_LINK)
ift->ifa_data = cif.ifa_data;
break;
case RTAX_NETMASK:
ift->ifa_netmask =
(struct sockaddr *)(void *)data;
if (sa->sa_len == 0) {
memset(data, 0, alen);
data += alen;
break;
}
memcpy(data, p, len);
data += len;
break;
case RTAX_BRD:
ift->ifa_broadaddr =
(struct sockaddr *)(void *)data;
memcpy(data, p, len);
data += len;
break;
}
p += len;
}
ift = (ift->ifa_next = ift + 1);
break;
}
}
free(buf);
if (--ift >= ifa) {
ift->ifa_next = NULL;
*pif = ifa;
} else {
*pif = NULL;
free(ifa);
}
return (0);
}
void
freeifaddrs(struct ifaddrs *ifp)
{
_DIAGASSERT(ifp != NULL);
free(ifp);
}