libnetutils/ifc_utils.c - android_system_core - Gitiles

 /*
  * Copyright 2008, The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <string.h>
 #include <errno.h>

 #include <sys/socket.h>
 #include <sys/select.h>
 #include <sys/types.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>

 #include <linux/if.h>
 #include <linux/sockios.h>
 #include <linux/route.h>
 #include <linux/wireless.h>

 #ifdef ANDROID
 #define LOG_TAG "NetUtils"
 #include <cutils/log.h>
 #include <cutils/properties.h>
 #else
 #include <stdio.h>
 #include <string.h>
 #define LOGD printf
 #define LOGW printf
 #endif

 static int ifc_ctl_sock = -1;
 void printerr(char *fmt, ...);

 static const char *ipaddr_to_string(uint32_t addr)
 {
     struct in_addr in_addr;

     in_addr.s_addr = addr;
     return inet_ntoa(in_addr);
 }

 int ifc_init(void)
 {
     if (ifc_ctl_sock == -1) {
         ifc_ctl_sock = socket(AF_INET, SOCK_DGRAM, 0);
         if (ifc_ctl_sock < 0) {
             printerr("socket() failed: %s\n", strerror(errno));
         }
     }
     return ifc_ctl_sock < 0 ? -1 : 0;
 }

 void ifc_close(void)
 {
     if (ifc_ctl_sock != -1) {
         (void)close(ifc_ctl_sock);
         ifc_ctl_sock = -1;
     }
 }

 static void ifc_init_ifr(const char *name, struct ifreq *ifr)
 {
     memset(ifr, 0, sizeof(struct ifreq));
     strncpy(ifr->ifr_name, name, IFNAMSIZ);
     ifr->ifr_name[IFNAMSIZ - 1] = 0;
 }

 int ifc_get_hwaddr(const char *name, void *ptr)
 {
     int r;
     struct ifreq ifr;
     ifc_init_ifr(name, &ifr);

     r = ioctl(ifc_ctl_sock, SIOCGIFHWADDR, &ifr);
     if(r < 0) return -1;

     memcpy(ptr, &ifr.ifr_hwaddr.sa_data, 6);
     return 0;
 }

 int ifc_get_ifindex(const char *name, int *if_indexp)
 {
     int r;
     struct ifreq ifr;
     ifc_init_ifr(name, &ifr);

     r = ioctl(ifc_ctl_sock, SIOCGIFINDEX, &ifr);
     if(r < 0) return -1;

     *if_indexp = ifr.ifr_ifindex;
     return 0;
 }

 static int ifc_set_flags(const char *name, unsigned set, unsigned clr)
 {
     struct ifreq ifr;
     ifc_init_ifr(name, &ifr);

     if(ioctl(ifc_ctl_sock, SIOCGIFFLAGS, &ifr) < 0) return -1;
     ifr.ifr_flags = (ifr.ifr_flags & (~clr)) | set;
     return ioctl(ifc_ctl_sock, SIOCSIFFLAGS, &ifr);
 }

 int ifc_up(const char *name)
 {
     return ifc_set_flags(name, IFF_UP, 0);
 }

 int ifc_down(const char *name)
 {
     return ifc_set_flags(name, 0, IFF_UP);
 }

 static void init_sockaddr_in(struct sockaddr *sa, in_addr_t addr)
 {
     struct sockaddr_in *sin = (struct sockaddr_in *) sa;
     sin->sin_family = AF_INET;
     sin->sin_port = 0;
     sin->sin_addr.s_addr = addr;
 }

 int ifc_set_addr(const char *name, in_addr_t addr)
 {
     struct ifreq ifr;

     ifc_init_ifr(name, &ifr);
     init_sockaddr_in(&ifr.ifr_addr, addr);

     return ioctl(ifc_ctl_sock, SIOCSIFADDR, &ifr);
 }

 int ifc_set_mask(const char *name, in_addr_t mask)
 {
     struct ifreq ifr;

     ifc_init_ifr(name, &ifr);
     init_sockaddr_in(&ifr.ifr_addr, mask);

     return ioctl(ifc_ctl_sock, SIOCSIFNETMASK, &ifr);
 }

 int ifc_get_info(const char *name, in_addr_t *addr, in_addr_t *mask, unsigned *flags)
 {
     struct ifreq ifr;
     ifc_init_ifr(name, &ifr);

     if (addr != NULL) {
         if(ioctl(ifc_ctl_sock, SIOCGIFADDR, &ifr) < 0) {
             *addr = 0;
         } else {
             *addr = ((struct sockaddr_in*) &ifr.ifr_addr)->sin_addr.s_addr;
         }
     }

     if (mask != NULL) {
         if(ioctl(ifc_ctl_sock, SIOCGIFNETMASK, &ifr) < 0) {
             *mask = 0;
         } else {
             *mask = ((struct sockaddr_in*) &ifr.ifr_addr)->sin_addr.s_addr;
         }
     }

     if (flags != NULL) {
         if(ioctl(ifc_ctl_sock, SIOCGIFFLAGS, &ifr) < 0) {
             *flags = 0;
         } else {
             *flags = ifr.ifr_flags;
         }
     }

     return 0;
 }


 int ifc_create_default_route(const char *name, in_addr_t addr)
 {
     struct rtentry rt;

     memset(&rt, 0, sizeof(rt));

     rt.rt_dst.sa_family = AF_INET;
     rt.rt_flags = RTF_UP | RTF_GATEWAY;
     rt.rt_dev = (void*) name;
     init_sockaddr_in(&rt.rt_genmask, 0);
     init_sockaddr_in(&rt.rt_gateway, addr);

     return ioctl(ifc_ctl_sock, SIOCADDRT, &rt);
 }

 int ifc_add_host_route(const char *name, in_addr_t addr)
 {
     struct rtentry rt;
     int result;

     memset(&rt, 0, sizeof(rt));

     rt.rt_dst.sa_family = AF_INET;
     rt.rt_flags = RTF_UP | RTF_HOST;
     rt.rt_dev = (void*) name;
     init_sockaddr_in(&rt.rt_dst, addr);
     init_sockaddr_in(&rt.rt_genmask, 0);
     init_sockaddr_in(&rt.rt_gateway, 0);

     ifc_init();
     result = ioctl(ifc_ctl_sock, SIOCADDRT, &rt);
     if (result < 0 && errno == EEXIST) {
         result = 0;
     }
     ifc_close();
     return result;
 }

 int ifc_disable(const char *ifname)
 {
     int result;

     ifc_init();
     result = ifc_down(ifname);
     ifc_set_addr(ifname, 0);
     ifc_close();
     return result;
 }

 int ifc_reset_connections(const char *ifname)
 {
 #ifdef HAVE_ANDROID_OS
     int result;
     in_addr_t myaddr;
     struct ifreq ifr;

     ifc_init();
     ifc_get_info(ifname, &myaddr, NULL, NULL);
     ifc_init_ifr(ifname, &ifr);
     init_sockaddr_in(&ifr.ifr_addr, myaddr);
     result = ioctl(ifc_ctl_sock, SIOCKILLADDR,  &ifr);
     ifc_close();

     return result;
 #else
     return 0;
 #endif
 }

 /*
  * Remove the routes associated with the named interface.
  */
 int ifc_remove_host_routes(const char *name)
 {
     char ifname[64];
     in_addr_t dest, gway, mask;
     int flags, refcnt, use, metric, mtu, win, irtt;
     struct rtentry rt;
     FILE *fp;
     struct in_addr addr;

     fp = fopen("/proc/net/route", "r");
     if (fp == NULL)
         return -1;
     /* Skip the header line */
     if (fscanf(fp, "%*[^\n]\n") < 0) {
         fclose(fp);
         return -1;
     }
     ifc_init();
     for (;;) {
         int nread = fscanf(fp, "%63s%X%X%X%d%d%d%X%d%d%d\n",
                            ifname, &dest, &gway, &flags, &refcnt, &use, &metric, &mask,
                            &mtu, &win, &irtt);
         if (nread != 11) {
             break;
         }
         if ((flags & (RTF_UP|RTF_HOST)) != (RTF_UP|RTF_HOST)
                 || strcmp(ifname, name) != 0) {
             continue;
         }
         memset(&rt, 0, sizeof(rt));
         rt.rt_dev = (void *)name;
         init_sockaddr_in(&rt.rt_dst, dest);
         init_sockaddr_in(&rt.rt_gateway, gway);
         init_sockaddr_in(&rt.rt_genmask, mask);
         addr.s_addr = dest;
         if (ioctl(ifc_ctl_sock, SIOCDELRT, &rt) < 0) {
             LOGD("failed to remove route for %s to %s: %s",
                  ifname, inet_ntoa(addr), strerror(errno));
         }
     }
     fclose(fp);
     ifc_close();
     return 0;
 }

 /*
  * Return the address of the default gateway
  *
  * TODO: factor out common code from this and remove_host_routes()
  * so that we only scan /proc/net/route in one place.
  */
 int ifc_get_default_route(const char *ifname)
 {
     char name[64];
     in_addr_t dest, gway, mask;
     int flags, refcnt, use, metric, mtu, win, irtt;
     int result;
     FILE *fp;

     fp = fopen("/proc/net/route", "r");
     if (fp == NULL)
         return 0;
     /* Skip the header line */
     if (fscanf(fp, "%*[^\n]\n") < 0) {
         fclose(fp);
         return 0;
     }
     ifc_init();
     result = 0;
     for (;;) {
         int nread = fscanf(fp, "%63s%X%X%X%d%d%d%X%d%d%d\n",
                            name, &dest, &gway, &flags, &refcnt, &use, &metric, &mask,
                            &mtu, &win, &irtt);
         if (nread != 11) {
             break;
         }
         if ((flags & (RTF_UP|RTF_GATEWAY)) == (RTF_UP|RTF_GATEWAY)
                 && dest == 0
                 && strcmp(ifname, name) == 0) {
             result = gway;
             break;
         }
     }
     fclose(fp);
     ifc_close();
     return result;
 }

 /*
  * Sets the specified gateway as the default route for the named interface.
  */
 int ifc_set_default_route(const char *ifname, in_addr_t gateway)
 {
     struct in_addr addr;
     int result;

     ifc_init();
     addr.s_addr = gateway;
     if ((result = ifc_create_default_route(ifname, gateway)) < 0) {
         LOGD("failed to add %s as default route for %s: %s",
              inet_ntoa(addr), ifname, strerror(errno));
     }
     ifc_close();
     return result;
 }

 /*
  * Removes the default route for the named interface.
  */
 int ifc_remove_default_route(const char *ifname)
 {
     struct rtentry rt;
     int result;

     ifc_init();
     memset(&rt, 0, sizeof(rt));
     rt.rt_dev = (void *)ifname;
     rt.rt_flags = RTF_UP|RTF_GATEWAY;
     init_sockaddr_in(&rt.rt_dst, 0);
     if ((result = ioctl(ifc_ctl_sock, SIOCDELRT, &rt)) < 0) {
         LOGD("failed to remove default route for %s: %s", ifname, strerror(errno));
     }
     ifc_close();
     return result;
 }

 int
 ifc_configure(const char *ifname,
         in_addr_t address,
         in_addr_t netmask,
         in_addr_t gateway,
         in_addr_t dns1,
         in_addr_t dns2) {

     char dns_prop_name[PROPERTY_KEY_MAX];

     ifc_init();

     if (ifc_up(ifname)) {
         printerr("failed to turn on interface %s: %s\n", ifname, strerror(errno));
         ifc_close();
         return -1;
     }
     if (ifc_set_addr(ifname, address)) {
         printerr("failed to set ipaddr %s: %s\n", ipaddr_to_string(address), strerror(errno));
         ifc_close();
         return -1;
     }
     if (ifc_set_mask(ifname, netmask)) {
         printerr("failed to set netmask %s: %s\n", ipaddr_to_string(netmask), strerror(errno));
         ifc_close();
         return -1;
     }
     if (ifc_create_default_route(ifname, gateway)) {
         printerr("failed to set default route %s: %s\n", ipaddr_to_string(gateway), strerror(errno));
         ifc_close();
         return -1;
     }

     ifc_close();

     snprintf(dns_prop_name, sizeof(dns_prop_name), "dhcp.%s.dns1", ifname);
     property_set(dns_prop_name, dns1 ? ipaddr_to_string(dns1) : "");
     snprintf(dns_prop_name, sizeof(dns_prop_name), "dhcp.%s.dns2", ifname);
     property_set(dns_prop_name, dns2 ? ipaddr_to_string(dns2) : "");

     return 0;
 }
	/*
	* Copyright 2008, The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include <stdio.h>
	#include <stdlib.h>
	#include <unistd.h>
	#include <string.h>
	#include <errno.h>

	#include <sys/socket.h>
	#include <sys/select.h>
	#include <sys/types.h>
	#include <netinet/in.h>
	#include <arpa/inet.h>

	#include <linux/if.h>
	#include <linux/sockios.h>
	#include <linux/route.h>
	#include <linux/wireless.h>

	#ifdef ANDROID
	#define LOG_TAG "NetUtils"
	#include <cutils/log.h>
	#include <cutils/properties.h>
	#else
	#include <stdio.h>
	#include <string.h>
	#define LOGD printf
	#define LOGW printf
	#endif

	static int ifc_ctl_sock = -1;
	void printerr(char *fmt, ...);

	static const char *ipaddr_to_string(uint32_t addr)
	{
	struct in_addr in_addr;

	in_addr.s_addr = addr;
	return inet_ntoa(in_addr);
	}

	int ifc_init(void)
	{
	if (ifc_ctl_sock == -1) {
	ifc_ctl_sock = socket(AF_INET, SOCK_DGRAM, 0);
	if (ifc_ctl_sock < 0) {
	printerr("socket() failed: %s\n", strerror(errno));
	}
	}
	return ifc_ctl_sock < 0 ? -1 : 0;
	}

	void ifc_close(void)
	{
	if (ifc_ctl_sock != -1) {
	(void)close(ifc_ctl_sock);
	ifc_ctl_sock = -1;
	}
	}

	static void ifc_init_ifr(const char name, struct ifreq ifr)
	{
	memset(ifr, 0, sizeof(struct ifreq));
	strncpy(ifr->ifr_name, name, IFNAMSIZ);
	ifr->ifr_name[IFNAMSIZ - 1] = 0;
	}

	int ifc_get_hwaddr(const char name, void ptr)
	{
	int r;
	struct ifreq ifr;
	ifc_init_ifr(name, &ifr);

	r = ioctl(ifc_ctl_sock, SIOCGIFHWADDR, &ifr);
	if(r < 0) return -1;

	memcpy(ptr, &ifr.ifr_hwaddr.sa_data, 6);
	return 0;
	}

	int ifc_get_ifindex(const char name, int if_indexp)
	{
	int r;
	struct ifreq ifr;
	ifc_init_ifr(name, &ifr);

	r = ioctl(ifc_ctl_sock, SIOCGIFINDEX, &ifr);
	if(r < 0) return -1;

	*if_indexp = ifr.ifr_ifindex;
	return 0;
	}

	static int ifc_set_flags(const char *name, unsigned set, unsigned clr)
	{
	struct ifreq ifr;
	ifc_init_ifr(name, &ifr);

	if(ioctl(ifc_ctl_sock, SIOCGIFFLAGS, &ifr) < 0) return -1;
	ifr.ifr_flags = (ifr.ifr_flags & (~clr)) \| set;
	return ioctl(ifc_ctl_sock, SIOCSIFFLAGS, &ifr);
	}

	int ifc_up(const char *name)
	{
	return ifc_set_flags(name, IFF_UP, 0);
	}

	int ifc_down(const char *name)
	{
	return ifc_set_flags(name, 0, IFF_UP);
	}

	static void init_sockaddr_in(struct sockaddr *sa, in_addr_t addr)
	{
	struct sockaddr_in sin = (struct sockaddr_in ) sa;
	sin->sin_family = AF_INET;
	sin->sin_port = 0;
	sin->sin_addr.s_addr = addr;
	}

	int ifc_set_addr(const char *name, in_addr_t addr)
	{
	struct ifreq ifr;

	ifc_init_ifr(name, &ifr);
	init_sockaddr_in(&ifr.ifr_addr, addr);

	return ioctl(ifc_ctl_sock, SIOCSIFADDR, &ifr);
	}

	int ifc_set_mask(const char *name, in_addr_t mask)
	{
	struct ifreq ifr;

	ifc_init_ifr(name, &ifr);
	init_sockaddr_in(&ifr.ifr_addr, mask);

	return ioctl(ifc_ctl_sock, SIOCSIFNETMASK, &ifr);
	}

	int ifc_get_info(const char name, in_addr_t addr, in_addr_t mask, unsigned flags)
	{
	struct ifreq ifr;
	ifc_init_ifr(name, &ifr);

	if (addr != NULL) {
	if(ioctl(ifc_ctl_sock, SIOCGIFADDR, &ifr) < 0) {
	*addr = 0;
	} else {
	addr = ((struct sockaddr_in) &ifr.ifr_addr)->sin_addr.s_addr;
	}
	}

	if (mask != NULL) {
	if(ioctl(ifc_ctl_sock, SIOCGIFNETMASK, &ifr) < 0) {
	*mask = 0;
	} else {
	mask = ((struct sockaddr_in) &ifr.ifr_addr)->sin_addr.s_addr;
	}
	}

	if (flags != NULL) {
	if(ioctl(ifc_ctl_sock, SIOCGIFFLAGS, &ifr) < 0) {
	*flags = 0;
	} else {
	*flags = ifr.ifr_flags;
	}
	}

	return 0;
	}


	int ifc_create_default_route(const char *name, in_addr_t addr)
	{
	struct rtentry rt;

	memset(&rt, 0, sizeof(rt));

	rt.rt_dst.sa_family = AF_INET;
	rt.rt_flags = RTF_UP \| RTF_GATEWAY;
	rt.rt_dev = (void*) name;
	init_sockaddr_in(&rt.rt_genmask, 0);
	init_sockaddr_in(&rt.rt_gateway, addr);

	return ioctl(ifc_ctl_sock, SIOCADDRT, &rt);
	}

	int ifc_add_host_route(const char *name, in_addr_t addr)
	{
	struct rtentry rt;
	int result;

	memset(&rt, 0, sizeof(rt));

	rt.rt_dst.sa_family = AF_INET;
	rt.rt_flags = RTF_UP \| RTF_HOST;
	rt.rt_dev = (void*) name;
	init_sockaddr_in(&rt.rt_dst, addr);
	init_sockaddr_in(&rt.rt_genmask, 0);
	init_sockaddr_in(&rt.rt_gateway, 0);

	ifc_init();
	result = ioctl(ifc_ctl_sock, SIOCADDRT, &rt);
	if (result < 0 && errno == EEXIST) {
	result = 0;
	}
	ifc_close();
	return result;
	}

	int ifc_disable(const char *ifname)
	{
	int result;

	ifc_init();
	result = ifc_down(ifname);
	ifc_set_addr(ifname, 0);
	ifc_close();
	return result;
	}

	int ifc_reset_connections(const char *ifname)
	{
	#ifdef HAVE_ANDROID_OS
	int result;
	in_addr_t myaddr;
	struct ifreq ifr;

	ifc_init();
	ifc_get_info(ifname, &myaddr, NULL, NULL);
	ifc_init_ifr(ifname, &ifr);
	init_sockaddr_in(&ifr.ifr_addr, myaddr);
	result = ioctl(ifc_ctl_sock, SIOCKILLADDR, &ifr);
	ifc_close();

	return result;
	#else
	return 0;
	#endif
	}

	/*
	* Remove the routes associated with the named interface.
	*/
	int ifc_remove_host_routes(const char *name)
	{
	char ifname[64];
	in_addr_t dest, gway, mask;
	int flags, refcnt, use, metric, mtu, win, irtt;
	struct rtentry rt;
	FILE *fp;
	struct in_addr addr;

	fp = fopen("/proc/net/route", "r");
	if (fp == NULL)
	return -1;
	/* Skip the header line */
	if (fscanf(fp, "%*[^\n]\n") < 0) {
	fclose(fp);
	return -1;
	}
	ifc_init();
	for (;;) {
	int nread = fscanf(fp, "%63s%X%X%X%d%d%d%X%d%d%d\n",
	ifname, &dest, &gway, &flags, &refcnt, &use, &metric, &mask,
	&mtu, &win, &irtt);
	if (nread != 11) {
	break;
	}
	if ((flags & (RTF_UP\|RTF_HOST)) != (RTF_UP\|RTF_HOST)
	\|\| strcmp(ifname, name) != 0) {
	continue;
	}
	memset(&rt, 0, sizeof(rt));
	rt.rt_dev = (void *)name;
	init_sockaddr_in(&rt.rt_dst, dest);
	init_sockaddr_in(&rt.rt_gateway, gway);
	init_sockaddr_in(&rt.rt_genmask, mask);
	addr.s_addr = dest;
	if (ioctl(ifc_ctl_sock, SIOCDELRT, &rt) < 0) {
	LOGD("failed to remove route for %s to %s: %s",
	ifname, inet_ntoa(addr), strerror(errno));
	}
	}
	fclose(fp);
	ifc_close();
	return 0;
	}

	/*
	* Return the address of the default gateway
	*
	* TODO: factor out common code from this and remove_host_routes()
	* so that we only scan /proc/net/route in one place.
	*/
	int ifc_get_default_route(const char *ifname)
	{
	char name[64];
	in_addr_t dest, gway, mask;
	int flags, refcnt, use, metric, mtu, win, irtt;
	int result;
	FILE *fp;

	fp = fopen("/proc/net/route", "r");
	if (fp == NULL)
	return 0;
	/* Skip the header line */
	if (fscanf(fp, "%*[^\n]\n") < 0) {
	fclose(fp);
	return 0;
	}
	ifc_init();
	result = 0;
	for (;;) {
	int nread = fscanf(fp, "%63s%X%X%X%d%d%d%X%d%d%d\n",
	name, &dest, &gway, &flags, &refcnt, &use, &metric, &mask,
	&mtu, &win, &irtt);
	if (nread != 11) {
	break;
	}
	if ((flags & (RTF_UP\|RTF_GATEWAY)) == (RTF_UP\|RTF_GATEWAY)
	&& dest == 0
	&& strcmp(ifname, name) == 0) {
	result = gway;
	break;
	}
	}
	fclose(fp);
	ifc_close();
	return result;
	}

	/*
	* Sets the specified gateway as the default route for the named interface.
	*/
	int ifc_set_default_route(const char *ifname, in_addr_t gateway)
	{
	struct in_addr addr;
	int result;

	ifc_init();
	addr.s_addr = gateway;
	if ((result = ifc_create_default_route(ifname, gateway)) < 0) {
	LOGD("failed to add %s as default route for %s: %s",
	inet_ntoa(addr), ifname, strerror(errno));
	}
	ifc_close();
	return result;
	}

	/*
	* Removes the default route for the named interface.
	*/
	int ifc_remove_default_route(const char *ifname)
	{
	struct rtentry rt;
	int result;

	ifc_init();
	memset(&rt, 0, sizeof(rt));
	rt.rt_dev = (void *)ifname;
	rt.rt_flags = RTF_UP\|RTF_GATEWAY;
	init_sockaddr_in(&rt.rt_dst, 0);
	if ((result = ioctl(ifc_ctl_sock, SIOCDELRT, &rt)) < 0) {
	LOGD("failed to remove default route for %s: %s", ifname, strerror(errno));
	}
	ifc_close();
	return result;
	}

	int
	ifc_configure(const char *ifname,
	in_addr_t address,
	in_addr_t netmask,
	in_addr_t gateway,
	in_addr_t dns1,
	in_addr_t dns2) {

	char dns_prop_name[PROPERTY_KEY_MAX];

	ifc_init();

	if (ifc_up(ifname)) {
	printerr("failed to turn on interface %s: %s\n", ifname, strerror(errno));
	ifc_close();
	return -1;
	}
	if (ifc_set_addr(ifname, address)) {
	printerr("failed to set ipaddr %s: %s\n", ipaddr_to_string(address), strerror(errno));
	ifc_close();
	return -1;
	}
	if (ifc_set_mask(ifname, netmask)) {
	printerr("failed to set netmask %s: %s\n", ipaddr_to_string(netmask), strerror(errno));
	ifc_close();
	return -1;
	}
	if (ifc_create_default_route(ifname, gateway)) {
	printerr("failed to set default route %s: %s\n", ipaddr_to_string(gateway), strerror(errno));
	ifc_close();
	return -1;
	}

	ifc_close();

	snprintf(dns_prop_name, sizeof(dns_prop_name), "dhcp.%s.dns1", ifname);
	property_set(dns_prop_name, dns1 ? ipaddr_to_string(dns1) : "");
	snprintf(dns_prop_name, sizeof(dns_prop_name), "dhcp.%s.dns2", ifname);
	property_set(dns_prop_name, dns2 ? ipaddr_to_string(dns2) : "");

	return 0;
	}