#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <syslog.h>
#include <fcntl.h>
#include <errno.h>
#undef __KERNEL__
#include <sys/socket.h>
#include <linux/if_packet.h>
#include <linux/if_ether.h>
#include <linux/sockios.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <net/if.h>
#include <string.h>
#include <stdarg.h>
#include <ctype.h>
#include <net/if_arp.h>
#include <netinet/in.h>
#include <signal.h>
#include <linux/types.h>

#define NIPQUAD(addr) \
	((unsigned char *) &addr)[0], \
	((unsigned char *) &addr)[1], \
	((unsigned char *) &addr)[2], \
	((unsigned char *) &addr)[3]

int
get_ctl_fd(void)
{
	int s_errno;
	int fd;

	fd = socket(PF_INET, SOCK_DGRAM, 0);
	if (fd >= 0)
		return fd;
	s_errno = errno;
	fd = socket(PF_PACKET, SOCK_DGRAM, 0);
	if (fd >= 0)
		return fd;
	fd = socket(PF_INET6, SOCK_DGRAM, 0);
	if (fd >= 0)
		return fd;
	errno = s_errno;
	perror("Cannot create control socket");
	return -1;
}

int
get_flags(char *intf)
{
	struct ifreq ifr;
	int sk = get_ctl_fd();
	if (sk < 0)
		return -1;
	memset(&ifr, 0, sizeof ifr);
	strncpy(ifr.ifr_name, intf, sizeof (ifr.ifr_name));
	if (ioctl(sk, SIOCGIFFLAGS, &ifr) < 0) {
		fprintf(stderr, "error getting device %s: ", intf);
		close(sk);
		return -1;
	}

	close(sk);
	return ifr.ifr_flags;
}

int
do_chflags(char *dev, __u32 flags, __u32 mask)
{
	struct ifreq ifr;
	int fd;
	int err;

	strcpy(ifr.ifr_name, dev);
	fd = get_ctl_fd();
	if (fd < 0)
		return -1;
	err = ioctl(fd, SIOCGIFFLAGS, &ifr);
	if (err) {
		perror("SIOCGIFFLAGS");
		close(fd);
		return -1;
	}
	if ((ifr.ifr_flags ^ flags) & mask) {
		ifr.ifr_flags &= ~mask;
		ifr.ifr_flags |= mask & flags;
		err = ioctl(fd, SIOCSIFFLAGS, &ifr);
		if (err)
			perror("SIOCSIFFLAGS");
	}
	close(fd);
	return err;
}

int
set_admin_up(char *dev, __u32 flags, __u32 mask)
{
	mask |= IFF_UP;
	flags |= IFF_UP;
	return do_chflags(dev, flags, mask);
}

int
set_admin_down(char *dev, __u32 flags, __u32 mask)
{
	mask |= IFF_UP;
	flags &= ~IFF_UP;
	return do_chflags(dev, flags, mask);
}

int
print_hw_addr(char *smac)
{
	printf(" %x:%x:%x:%x:%x:%x ", smac[0] & 0xff,
	       smac[1] & 0xff, smac[2] & 0xff, smac[3] & 0xff, smac[4] & 0xff,
	       smac[5] & 0xff);
}

int
get_hw_addr(char *name, char *smac)
{
	struct ifreq ifr;

	int s = get_ctl_fd();
	if (s < 0)
		return -1;

	strncpy(ifr.ifr_name, name, sizeof (ifr.ifr_name));

	if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0) {
		fprintf(stderr, "ioctl(SIOCGIFHWADDR): %s", name);
		return -1;
	}

	if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
		fprintf(stderr, "interface %s is not Ethernet!", name);
		return -1;
	}

	memcpy(smac, ifr.ifr_hwaddr.sa_data, ETH_ALEN);

	//print_hw_addr(smac);

	return 0;

}
static 
__inline__ __u32 inet_make_mask(int logmask)
{
	if (logmask)
		return htonl(~((1<<(32-logmask))-1));
	return 0;
}


#define satosin(sa)  ((struct sockaddr_in *) (sa))
int
add_ifa(char *intf, __u32 NiIPAddr, __u32 NetMask)
{
	int sk;
	struct ifreq ifr;
	__u32 bcastMask = (NiIPAddr & NetMask) | ~NetMask;

	sk = get_ctl_fd();
	if (sk < 0)
		return -1;

	memset(&ifr, 0, sizeof ifr);
	strncpy(ifr.ifr_name, intf, IFNAMSIZ - 1);

	satosin(&ifr.ifr_addr)->sin_family = AF_INET;
	satosin(&ifr.ifr_addr)->sin_addr.s_addr = NiIPAddr;

	if (0 > ioctl(sk, SIOCSIFADDR, (char *) &ifr)) {
		printf("Failed SIOCSIFADDR on %s\n", intf);
		close(sk);
		return -1;
	}
	//                    
	//   Set new Network Mask.
	//
	satosin(&ifr.ifr_addr)->sin_family = AF_INET;
	satosin(&ifr.ifr_addr)->sin_addr.s_addr = bcastMask;
	//
	if (NiIPAddr && (0 > ioctl(sk, SIOCSIFBRDADDR, (char *) &ifr))) {
		printf("Failed SIOCSIFBRDADDR on %s\n", intf);
		close(sk);
		return -1;
	}
	satosin(&ifr.ifr_addr)->sin_family = AF_INET;
	satosin(&ifr.ifr_addr)->sin_addr.s_addr = NetMask;
	if (NiIPAddr && (0 > ioctl(sk, SIOCSIFNETMASK, (char *) &ifr))) {
		printf("Failed SIOCSIFNETMASK on %s\n", intf);
		close(sk);
		return -1;
	}

	close(sk);
	return 0;
}

// set ip address from MAC
// smac[6] 
// get_hw_addr("eth0",&smac);
// build ipfrommac
//__u32 netmask = inet_make_mask(24);
// ret = add_ifa("eth0", ipfrommac[0], netmask);
// set_admin_up("eth0",0.0);

int
main(int argc, char *argv[])
{
	char smac[6];
	__u32 ethip = 0;
	__u32 netmask = inet_make_mask(24);

	if (argc != 2) {
		fprintf(stderr,"Device name is needed\n");
		exit(0);
	}
// argv[1] contains the eth device name
	int ret = get_hw_addr(argv[1], smac);
	if (ret < 0) {
		fprintf(stderr,"Failed to get mac address of %s\n",argv[1]);
		exit(0);
	}
	print_hw_addr(smac);
	fprintf(stdout, "IP address %d.%d.%d.%d\n",
		smac[2] & 0xff, smac[3] & 0xff, smac[4] & 0xff, smac[5] & 0xff);

	ethip |= smac[5] & 0xff;
	ethip <<= 8;
	ethip |= smac[4] & 0xff;
	ethip <<= 8;
	ethip |= smac[3] & 0xff;
	ethip <<= 8;
	ethip |= smac[2] & 0xff;

	fprintf(stdout,"converted IP %d.%d.%d.%d\n", NIPQUAD(ethip));
	ret = add_ifa(argv[1], ethip, netmask);
	if (ret < 0) {
		fprintf(stderr,"Failed to set IP  address of %s\n",argv[1]);
		exit(0);
	}
	ret = set_admin_up(argv[1], 0, 0);
	if (ret < 0) {
		fprintf(stderr,"Failed to bring up %s\n",argv[1]);
		exit(0);
	}

	return ret;
}