/* 
   Unix SMB/CIFS implementation.
   Samba utility functions
   Copyright (C) Andrew Tridgell 1998
   Copyright (C) Jeremy Allison 2007
   Copyright (C) Jelmer Vernooij <jelmer@samba.org> 2007
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.
   
   This program 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 General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "replace.h"
#include "system/network.h"

#include <unistd.h>
#include <stdio.h>
#include <sys/types.h>

#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif

#ifndef SIOCGIFCONF
#ifdef HAVE_SYS_SOCKIO_H
#include <sys/sockio.h>
#endif
#endif

#ifdef HAVE_IFACE_GETIFADDRS
#define _FOUND_IFACE_ANY
#else

void freeifaddrs(struct ifaddrs *ifp)
{
	free(ifp->ifa_name);
	free(ifp->ifa_addr);
	free(ifp->ifa_netmask);
	free(ifp->ifa_dstaddr);
	if (ifp->ifa_next != NULL)
		freeifaddrs(ifp->ifa_next);
	free(ifp);
}

struct sockaddr *sockaddr_dup(struct sockaddr *sa)
{
	struct sockaddr *ret = calloc(1, sa->sa_len);
	if (ret == NULL)
		return NULL;
	memcpy(ret, sa, sa->sa_len);
	return ret;
}
#endif

#if HAVE_IFACE_IFCONF

/* this works for Linux 2.2, Solaris 2.5, SunOS4, HPUX 10.20, OSF1
   V4.0, Ultrix 4.4, SCO Unix 3.2, IRIX 6.4 and FreeBSD 3.2.

   It probably also works on any BSD style system.  */

int getifaddrs(struct ifaddrs **ifap)
{
	struct ifconf ifc;
	char buff[8192];
	int fd, i, n;
	struct ifreq *ifr=NULL;
	int total = 0;
	struct in_addr ipaddr;
	struct in_addr nmask;
	char *iname;
	struct ifaddrs *curif, *lastif;

	*ifap = NULL;

	if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
		return -1;
	}
  
	ifc.ifc_len = sizeof(buff);
	ifc.ifc_buf = buff;

	if (ioctl(fd, SIOCGIFCONF, &ifc) != 0) {
		close(fd);
		return -1;
	} 

	ifr = ifc.ifc_req;
  
	n = ifc.ifc_len / sizeof(struct ifreq);

	/* Loop through interfaces, looking for given IP address */
	for (i=n-1;i>=0 && total < max_interfaces;i--) {
		if (ioctl(fd, SIOCGIFADDR, &ifr[i]) != 0) {
			freeifaddrs(*ifap);
		}

		curif = calloc(1, sizeof(struct ifaddrs));
		if (lastif == NULL) {
			*ifap = curif;
		} else {
			lastif->ifa_next = (*ifap);
		}

		curif->ifa_name = strdup(ifr[i].ifr_name);
		curif->ifa_flags = ifreq.ifr_flags;
		curif->ifa_addr = sockaddr_dup(&ifr[i].ifr_addr);
		curif->ifa_dstaddr = NULL;
		curif->ifa_data = NULL;
		curif->ifa_next = NULL;
		curif->ifa_netmask = NULL;

		if (ioctl(fd, SIOCGIFFLAGS, &ifr[i]) != 0) {
			freeifaddrs(*ifap);
			return -1;
		}  

		if (!(ifr[i].ifr_flags & IFF_UP)) {
			freeifaddrs(curif);
			continue;
		}

		if (ioctl(fd, SIOCGIFNETMASK, &ifr[i]) != 0) {
			freeifaddrs(*ifap);
			return -1;
		}  

		curif->ifa_netmask = sockaddr_dup(&ifr[i].ifr_addr);

		lastif = curif;
	}

	close(fd);

	return 0;
}  

#define _FOUND_IFACE_ANY
#endif /* HAVE_IFACE_IFCONF */
#ifdef HAVE_IFACE_IFREQ

#ifndef I_STR
#include <sys/stropts.h>
#endif

/****************************************************************************
this should cover most of the streams based systems
Thanks to Andrej.Borsenkow@mow.siemens.ru for several ideas in this code
****************************************************************************/
int getifaddrs(struct ifaddrs **ifap)
{
	struct ifreq ifreq;
	struct strioctl strioctl;
	char buff[8192];
	int fd, i, n;
	struct ifreq *ifr=NULL;
	int total = 0;
	struct in_addr ipaddr;
	struct in_addr nmask;
	char *iname;
	struct ifaddrs *curif;

	*ifap = NULL;

	if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
		return -1;
	}
  
	strioctl.ic_cmd = SIOCGIFCONF;
	strioctl.ic_dp  = buff;
	strioctl.ic_len = sizeof(buff);
	if (ioctl(fd, I_STR, &strioctl) < 0) {
		close(fd);
		return -1;
	} 

	/* we can ignore the possible sizeof(int) here as the resulting
	   number of interface structures won't change */
	n = strioctl.ic_len / sizeof(struct ifreq);

	/* we will assume that the kernel returns the length as an int
           at the start of the buffer if the offered size is a
           multiple of the structure size plus an int */
	if (n*sizeof(struct ifreq) + sizeof(int) == strioctl.ic_len) {
		ifr = (struct ifreq *)(buff + sizeof(int));  
	} else {
		ifr = (struct ifreq *)buff;  
	}

	/* Loop through interfaces */

	for (i = 0; i<n && total < max_interfaces; i++) {
		ifreq = ifr[i];
  
		strioctl.ic_cmd = SIOCGIFFLAGS;
		strioctl.ic_dp  = (char *)&ifreq;
		strioctl.ic_len = sizeof(struct ifreq);
		if (ioctl(fd, I_STR, &strioctl) != 0) {
			freeifaddrs(*ifap);
			return -1;
		}
		
		if (!(ifreq.ifr_flags & IFF_UP)) {
			continue;
		}

		strioctl.ic_cmd = SIOCGIFADDR;
		strioctl.ic_dp  = (char *)&ifreq;
		strioctl.ic_len = sizeof(struct ifreq);
		if (ioctl(fd, I_STR, &strioctl) != 0) {
			freeifaddrs(*ifap);
			return -1;
		}

		curif = calloc(1, sizeof(struct ifaddrs));
		if (lastif == NULL) {
			*ifap = curif;
		} else {
			lastif->ifa_next = (*ifap);
		}

		curif->ifa_name = strdup(ifreq.ifr_name);
		curif->ifa_flags = ifreq.ifr_flags;
		curif->ifa_addr = sockaddr_dup(&ifreq.ifr_addr);
		curif->ifa_dstaddr = NULL;
		curif->ifa_data = NULL;
		curif->ifa_next = NULL;
		curif->ifa_netmask = NULL;

		strioctl.ic_cmd = SIOCGIFNETMASK;
		strioctl.ic_dp  = (char *)&ifreq;
		strioctl.ic_len = sizeof(struct ifreq);
		if (ioctl(fd, I_STR, &strioctl) != 0) {
			freeifaddrs(*ifap);
			return -1;
		}

		curif->ifa_netmask = sockaddr_dup(&ifreq.ifr_addr);

		lastif = curif;
	}

	close(fd);

	return 0;
}

#define _FOUND_IFACE_ANY
#endif /* HAVE_IFACE_IFREQ */
#ifdef HAVE_IFACE_AIX

/****************************************************************************
this one is for AIX (tested on 4.2)
****************************************************************************/
int getifaddrs(struct ifaddrs **ifap)
{
	char buff[8192];
	int fd, i;
	struct ifconf ifc;
	struct ifreq *ifr=NULL;
	struct in_addr ipaddr;
	struct in_addr nmask;
	char *iname;
	int total = 0;
	struct ifaddrs *curif, *lastif;

	*ifap = NULL;

	if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
		return -1;
	}

	ifc.ifc_len = sizeof(buff);
	ifc.ifc_buf = buff;

	if (ioctl(fd, SIOCGIFCONF, &ifc) != 0) {
		close(fd);
		return -1;
	}

	ifr = ifc.ifc_req;

	/* Loop through interfaces */
	i = ifc.ifc_len;

	while (i > 0) {
		uint_t inc;

		inc = ifr->ifr_addr.sa_len;

		if (ioctl(fd, SIOCGIFADDR, ifr) != 0) {
			freeaddrinfo(*ifap);
			return -1;
		}

		curif = calloc(1, sizeof(struct ifaddrs));
		if (lastif == NULL) {
			*ifap = curif;
		} else {
			lastif->ifa_next = (*ifap);
		}

		curif->ifa_name = strdup(ifr->ifr_name);
		curif->ifa_flags = ifr->ifr_flags;
		curif->ifa_addr = sockaddr_dup(&ifr->ifr_addr);
		curif->ifa_dstaddr = NULL;
		curif->ifa_data = NULL;
		curif->ifa_netmask = NULL;
		curif->ifa_next = NULL;

		if (ioctl(fd, SIOCGIFFLAGS, ifr) != 0) {
			freeaddrinfo(*ifap);
			return -1;
		}

		if (!(ifr->ifr_flags & IFF_UP)) {
			freeaddrinfo(curif);
			continue;
		}

		if (ioctl(fd, SIOCGIFNETMASK, ifr) != 0) {
			freeaddrinfo(*ifap);
			return -1;
		}

		curif->ifa_netmask = sockaddr_dup(&ifr->ifr_addr);

		lastif = curif;

	next:
		/*
		 * Patch from Archie Cobbs (archie@whistle.com).  The
		 * addresses in the SIOCGIFCONF interface list have a
		 * minimum size. Usually this doesn't matter, but if
		 * your machine has tunnel interfaces, etc. that have
		 * a zero length "link address", this does matter.  */

		if (inc < sizeof(ifr->ifr_addr))
			inc = sizeof(ifr->ifr_addr);
		inc += IFNAMSIZ;

		ifr = (struct ifreq*) (((char*) ifr) + inc);
		i -= inc;
	}

	close(fd);
	return 0;
}

#define _FOUND_IFACE_ANY
#endif /* HAVE_IFACE_AIX */
#ifndef _FOUND_IFACE_ANY
int getifaddrs(struct ifaddrs **ifap)
{
	errno = ENOSYS;
	return -1;
}
#endif

#ifdef AUTOCONF_TEST
/* this is the autoconf driver to test get_interfaces() */

 int main()
{
	struct ifaddrs *ifs;
	int total = get_interfaces(ifaces, MAX_INTERFACES);
	int i;

	int ret = getifaddrs(&ifs);
	if (ret != 0) {
		perror("getifaddrs() failed");
		return 1;
	}

	while (ifs) {
		printf("%-10s ", ifs->ifr_name);
		printf("IP=%s ", inet_ntoa(((struct sockaddr_in *)ifs->ifr_addr)->sin_addr));
		printf("NETMASK=%s\n", inet_ntoa(((struct sockaddr_in *)ifs->ifr_netmask)->sin_addr));
	}
	return 0;
}
#endif