/*
 * (C)opyright 1995-1998 Darren Reed. (from tcplog)
 *
 * See the IPFILTER.LICENCE file for details on licencing.
 *
 */
#include <sys/param.h>
#include <sys/types.h>
#include <sys/mbuf.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#ifdef __FreeBSD__
# include <sys/dirent.h>
#else
# include <sys/dir.h>
#endif
#include <net/bpf.h>

#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/udp.h>
#include <netinet/tcp.h>

#include <stdio.h>
#include <netdb.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#ifdef __NetBSD__
# include <paths.h>
#endif
#include <ctype.h>
#include <signal.h>
#include <errno.h>

#include "ipsend.h"


/*
 * the code herein is dervied from libpcap.
 */
static  u_char  *buf = NULL;
static  int     bufsize = 0, timeout = 1;


int
initdevice(char *device, int tout)
{
        struct  bpf_version bv;
        struct  timeval to;
        struct  ifreq ifr;
#ifdef _PATH_BPF
        char    *bpfname = _PATH_BPF;
        int     fd;

        if ((fd = open(bpfname, O_RDWR)) < 0)
            {
                fprintf(stderr, "no bpf devices available as /dev/bpfxx\n");
                return (-1);
            }
#else
        char    bpfname[16];
        int     fd = 0, i;

        for (i = 0; i < 16; i++)
            {
                (void) snprintf(bpfname, sizeof(bpfname), "/dev/bpf%d", i);
                if ((fd = open(bpfname, O_RDWR)) >= 0)
                        break;
            }
        if (i == 16)
            {
                fprintf(stderr, "no bpf devices available as /dev/bpfxx\n");
                return (-1);
            }
#endif

        if (ioctl(fd, BIOCVERSION, (caddr_t)&bv) < 0)
            {
                perror("BIOCVERSION");
                return (-1);
            }
        if (bv.bv_major != BPF_MAJOR_VERSION ||
            bv.bv_minor < BPF_MINOR_VERSION)
            {
                fprintf(stderr, "kernel bpf (v%d.%d) filter out of date:\n",
                        bv.bv_major, bv.bv_minor);
                fprintf(stderr, "current version: %d.%d\n",
                        BPF_MAJOR_VERSION, BPF_MINOR_VERSION);
                return (-1);
            }

        (void) strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
        if (ioctl(fd, BIOCSETIF, &ifr) == -1)
            {
                fprintf(stderr, "%s(%d):", ifr.ifr_name, fd);
                perror("BIOCSETIF");
                exit(1);
            }
        /*
         * get kernel buffer size
         */
        if (ioctl(fd, BIOCGBLEN, &bufsize) == -1)
            {
                perror("BIOCSBLEN");
                exit(-1);
            }
        buf = (u_char*)malloc(bufsize);
        /*
         * set the timeout
         */
        timeout = tout;
        to.tv_sec = 1;
        to.tv_usec = 0;
        if (ioctl(fd, BIOCSRTIMEOUT, (caddr_t)&to) == -1)
            {
                perror("BIOCSRTIMEOUT");
                exit(-1);
            }

        (void) ioctl(fd, BIOCFLUSH, 0);
        return (fd);
}


/*
 * output an IP packet onto a fd opened for /dev/bpf
 */
int
sendip(int fd, char *pkt, int len)
{
        if (write(fd, pkt, len) == -1)
            {
                perror("send");
                return (-1);
            }

        return (len);
}