#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <error.h>
#include <net/route.h> int setifaddr (char *ifname, Char *ipaddr, char *mask,char *gateway)
{
int fd;
int RC;
struct ifreq IFR;
struct sockaddr_in *sin;
struct Rtentry RT;
FD = socket (af_inet, SOCK_DGRAM, 0);
if (FD < 0)
{
perror ("socket error");
return-1;
}memset (&ifr,0,sizeof (IFR));
strcpy (ifr.ifr_name,ifname);
sin = (struct sockaddr_in*) &ifr.ifr_addr;
sin->sin_family = af_inet;
//ipaddr
if (Inet_aton (ipaddr,& (sin->sin_addr)) < 0)
{
perror ("Inet_aton error");
return-2;
}
if (IOCTL (FD,SIOCSIFADDR,&IFR) < 0)
{
perror ("IOCTL siocsifaddr error");
return-3;
}
//netmask
if (Inet_aton (mask,& (sin->sin_addr)) < 0)
{
perror ("Inet_pton error");
return-4;
}
if (IOCTL (FD, Siocsifnetmask, &IFR) < 0)
{
perror ("IOCTL");
return-5;
}
//gateway
memset (&rt, 0, sizeof (struct rtentry));
memset (sin, 0, sizeof (struct sockaddr_in));
sin->sin_family = af_inet;
sin->sin_port = 0;if (Inet_aton (Gateway, &sin->sin_addr) <0)
{
printf ("Inet_aton error\n");
}
memcpy (&rt.rt_gateway, sin, sizeof (struct sockaddr_in));
(struct sockaddr_in *) &rt.rt_dst)->sin_family=af_inet;
(struct sockaddr_in *) &rt.rt_genmask)->sin_family=af_inet;
rt.rt_flags = Rtf_gateway;if (IOCTL (FD, SIOCADDRT, &rt) <0)
{
Zerror ("IOCTL (SIOCADDRT) error in set_default_route\n");
Close (FD);
return-1;
}Close (FD);
return RC;
}
Notes Linux C language implementation of static IP address, mask, gateway settings
