// Mateusz Guzik, https://bugzilla.redhat.com/show_bug.cgi?id=1097315#c19

#include <errno.h>
#include <fnmatch.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <sys/socket.h>
#include <unistd.h>
#include <stdio.h>


#include <linux/netlink.h>
#include <libaudit.h>

static int
nl_open (void)
{
	  return socket (AF_NETLINK, SOCK_RAW, NETLINK_AUDIT);
}

static int
nl_send (int fd, unsigned type, unsigned flags, const void *data, size_t size)
{
  struct sockaddr_nl addr;
  struct msghdr msg;
  struct nlmsghdr nlm;
  struct iovec iov[2];
  ssize_t res;

  nlm.nlmsg_len = NLMSG_LENGTH (size);
  nlm.nlmsg_type = type;
  nlm.nlmsg_flags = NLM_F_REQUEST | flags;
  nlm.nlmsg_seq = 0;
  nlm.nlmsg_pid = 0;
  iov[0].iov_base = &nlm;
  iov[0].iov_len = sizeof (nlm);
  iov[1].iov_base = (void *)data;
  iov[1].iov_len = size;
  addr.nl_family = AF_NETLINK;
  addr.nl_pid = 0;
  addr.nl_groups = 0;
  msg.msg_name = &addr;
  msg.msg_namelen = sizeof (addr);
  msg.msg_iov = iov;
  msg.msg_iovlen = 2;
  msg.msg_control = NULL;
  msg.msg_controllen = 0;
  msg.msg_flags = 0;
  res = sendmsg (fd, &msg, 0);
  if (res == -1)
    return -1;
  if ((size_t)res != nlm.nlmsg_len)
    {
      errno = EIO;
      return -1;
    }
  return 0;
}

static int
nl_recv (int fd, unsigned type, void *buf, size_t size)
{
  struct sockaddr_nl addr;
  struct msghdr msg;
  struct nlmsghdr nlm;
  struct iovec iov[2];
  ssize_t res;

 again:
  iov[0].iov_base = &nlm;
  iov[0].iov_len = sizeof (nlm);
  msg.msg_name = &addr;
  msg.msg_namelen = sizeof (addr);
  msg.msg_iov = iov;
  msg.msg_iovlen = 1;
  msg.msg_control = NULL;
  msg.msg_controllen = 0;
  if (type != NLMSG_ERROR)
    {
      res = recvmsg (fd, &msg, MSG_PEEK);
      if (res == -1)
        return -1;
      if (res != NLMSG_LENGTH (0))
        {
          errno = EIO;
          return -1;
        }
      if (nlm.nlmsg_type == NLMSG_ERROR)
        {
          struct nlmsgerr err;

          iov[1].iov_base = &err;
          iov[1].iov_len = sizeof (err);
          msg.msg_iovlen = 2;
          res = recvmsg (fd, &msg, 0);
          if (res == -1)
            return -1;
          if ((size_t)res != NLMSG_LENGTH (sizeof (err))
              || nlm.nlmsg_type != NLMSG_ERROR)
            {
              errno = EIO;
              return -1;
            }
          if (err.error == 0)
            goto again;
          errno = -err.error;
          return -1;
        }
    }
  if (size != 0)
    {
      iov[1].iov_base = buf;
      iov[1].iov_len = size;
      msg.msg_iovlen = 2;
    }
  res = recvmsg (fd, &msg, 0);
  if (res == -1)
    return -1;
  if ((size_t)res != NLMSG_LENGTH (size)
      || nlm.nlmsg_type != type)
    {
      errno = EIO;
      return -1;
    }
  return 0;
}


static int
nl_recv_ack (int fd)
{
  struct nlmsgerr err;

  if (nl_recv (fd, NLMSG_ERROR, &err, sizeof (err)) != 0)
    return -1;
  if (err.error != 0)
    {
      errno = -err.error;
      return -1;
    }
  return 0;
}

int
main(void)
{
	struct audit_tty_status *old_status, new_status = { 0 };
	int fd;
        int i=0;
        int h = 0;

	fd = nl_open();
	if (fd < 0) {
		perror("nl_open");
		exit(1);
	}

	new_status.enabled = 1;
	if (nl_send (fd, AUDIT_TTY_SET, NLM_F_ACK, &new_status, sizeof (new_status)) != 0 ||
		nl_recv_ack (fd) != 0) {
		fprintf(stderr, "failed\n");
		exit(1);
	}

	printf("foo bar\n");
	//getchar();
	for (;;) {
		audit_log_user_message(fd, AUDIT_USER_TTY, "foo", "bar", "baz", "quux", 1);
                i = (i+1) & 65535;
	        (i == 0 ) && printf("heartbeat %d\n", h+=1);
        }
	close(fd);
}