iwlist.c

This package contains the Wireless tools, used to manipulate the Wireless Extensions. The Wireless

      printf("                    Mode:%s\n",
	     iw_operation_mode[event->u.mode]);
      break;
    case SIOCGIWNAME:
      printf("                    Protocol:%-1.16s\n", event->u.name);
      break;
    case SIOCGIWESSID:
      {
	char essid[IW_ESSID_MAX_SIZE+1];
	memset(essid, '\0', sizeof(essid));
	if((event->u.essid.pointer) && (event->u.essid.length))
	  memcpy(essid, event->u.essid.pointer, event->u.essid.length);
	if(event->u.essid.flags)
	  {
	    /* Does it have an ESSID index ? */
	    if((event->u.essid.flags & IW_ENCODE_INDEX) > 1)
	      printf("                    ESSID:\"%s\" [%d]\n", essid,
		     (event->u.essid.flags & IW_ENCODE_INDEX));
	    else
	      printf("                    ESSID:\"%s\"\n", essid);
	  }
	else
	  printf("                    ESSID:off/any/hidden\n");
      }
      break;
    case SIOCGIWENCODE:
      {
	unsigned char	key[IW_ENCODING_TOKEN_MAX];
	if(event->u.data.pointer)
	  memcpy(key, event->u.data.pointer, event->u.data.length);
	else
	  event->u.data.flags |= IW_ENCODE_NOKEY;
	printf("                    Encryption key:");
	if(event->u.data.flags & IW_ENCODE_DISABLED)
	  printf("off\n");
	else
	  {
	    /* Display the key */
	    iw_print_key(buffer, sizeof(buffer), key, event->u.data.length,
			 event->u.data.flags);
	    printf("%s", buffer);

	    /* Other info... */
	    if((event->u.data.flags & IW_ENCODE_INDEX) > 1)
	      printf(" [%d]", event->u.data.flags & IW_ENCODE_INDEX);
	    if(event->u.data.flags & IW_ENCODE_RESTRICTED)
	      printf("   Security mode:restricted");
	    if(event->u.data.flags & IW_ENCODE_OPEN)
	      printf("   Security mode:open");
	    printf("\n");
	  }
      }
      break;
    case SIOCGIWRATE:
      if(state->val_index == 0)
	printf("                    Bit Rates:");
      else
	if((state->val_index % 5) == 0)
	  printf("\n                              ");
	else
	  printf("; ");
      iw_print_bitrate(buffer, sizeof(buffer), event->u.bitrate.value);
      printf("%s", buffer);
      /* Check for termination */
      if(stream->value == NULL)
	{
	  printf("\n");
	  state->val_index = 0;
	}
      else
	state->val_index++;
      break;
    case IWEVQUAL:
      {
	iw_print_stats(buffer, sizeof(buffer),
		       &event->u.qual, iw_range, has_range);
	printf("                    %s\n", buffer);
	break;
      }
    case IWEVGENIE:
      /* Informations Elements are complex, let's do only some of them */
      iw_print_gen_ie(event->u.data.pointer, event->u.data.length);
      break;
    case IWEVCUSTOM:
      {
	char custom[IW_CUSTOM_MAX+1];
	if((event->u.data.pointer) && (event->u.data.length))
	  memcpy(custom, event->u.data.pointer, event->u.data.length);
	custom[event->u.data.length] = '\0';
	printf("                    Extra:%s\n", custom);
      }
      break;
    default:
      printf("                    (Unknown Wireless Token 0x%04X)\n",
	     event->cmd);
   }	/* switch(event->cmd) */
}

/*------------------------------------------------------------------*/
/*
 * Perform a scanning on one device
 */
static int
print_scanning_info(int		skfd,
		    char *	ifname,
		    char *	args[],		/* Command line args */
		    int		count)		/* Args count */
{
  struct iwreq		wrq;
  unsigned char *	buffer = NULL;		/* Results */
  int			buflen = IW_SCAN_MAX_DATA; /* Min for compat WE<17 */
  struct iw_range	range;
  int			has_range;
  struct timeval	tv;				/* Select timeout */
  int			timeout = 15000000;		/* 15s */

  /* Avoid "Unused parameter" warning */
  args = args; count = count;

  /* Get range stuff */
  has_range = (iw_get_range_info(skfd, ifname, &range) >= 0);

  /* Check if the interface could support scanning. */
  if((!has_range) || (range.we_version_compiled < 14))
    {
      fprintf(stderr, "%-8.16s  Interface doesn't support scanning.\n\n",
	      ifname);
      return(-1);
    }

  /* Init timeout value -> 250ms*/
  tv.tv_sec = 0;
  tv.tv_usec = 250000;

  /*
   * Here we should look at the command line args and set the IW_SCAN_ flags
   * properly
   */
  wrq.u.data.pointer = NULL;		/* Later */
  wrq.u.data.flags = 0;
  wrq.u.data.length = 0;

  /* Initiate Scanning */
  if(iw_set_ext(skfd, ifname, SIOCSIWSCAN, &wrq) < 0)
    {
      if(errno != EPERM)
	{
	  fprintf(stderr, "%-8.16s  Interface doesn't support scanning : %s\n\n",
		  ifname, strerror(errno));
	  return(-1);
	}
      /* If we don't have the permission to initiate the scan, we may
       * still have permission to read left-over results.
       * But, don't wait !!! */
#if 0
      /* Not cool, it display for non wireless interfaces... */
      fprintf(stderr, "%-8.16s  (Could not trigger scanning, just reading left-over results)\n", ifname);
#endif
      tv.tv_usec = 0;
    }
  timeout -= tv.tv_usec;

  /* Forever */
  while(1)
    {
      fd_set		rfds;		/* File descriptors for select */
      int		last_fd;	/* Last fd */
      int		ret;

      /* Guess what ? We must re-generate rfds each time */
      FD_ZERO(&rfds);
      last_fd = -1;

      /* In here, add the rtnetlink fd in the list */

      /* Wait until something happens */
      ret = select(last_fd + 1, &rfds, NULL, NULL, &tv);

      /* Check if there was an error */
      if(ret < 0)
	{
	  if(errno == EAGAIN || errno == EINTR)
	    continue;
	  fprintf(stderr, "Unhandled signal - exiting...\n");
	  return(-1);
	}

      /* Check if there was a timeout */
      if(ret == 0)
	{
	  unsigned char *	newbuf;

	realloc:
	  /* (Re)allocate the buffer - realloc(NULL, len) == malloc(len) */
	  newbuf = realloc(buffer, buflen);
	  if(newbuf == NULL)
	    {
	      if(buffer)
		free(buffer);
	      fprintf(stderr, "%s: Allocation failed\n", __FUNCTION__);
	      return(-1);
	    }
	  buffer = newbuf;

	  /* Try to read the results */
	  wrq.u.data.pointer = buffer;
	  wrq.u.data.flags = 0;
	  wrq.u.data.length = buflen;
	  if(iw_get_ext(skfd, ifname, SIOCGIWSCAN, &wrq) < 0)
	    {
	      /* Check if buffer was too small (WE-17 only) */
	      if((errno == E2BIG) && (range.we_version_compiled > 16))
		{
		  /* Some driver may return very large scan results, either
		   * because there are many cells, or because they have many
		   * large elements in cells (like IWEVCUSTOM). Most will
		   * only need the regular sized buffer. We now use a dynamic
		   * allocation of the buffer to satisfy everybody. Of course,
		   * as we don't know in advance the size of the array, we try
		   * various increasing sizes. Jean II */

		  /* Check if the driver gave us any hints. */
		  if(wrq.u.data.length > buflen)
		    buflen = wrq.u.data.length;
		  else
		    buflen *= 2;

		  /* Try again */
		  goto realloc;
		}

	      /* Check if results not available yet */
	      if(errno == EAGAIN)
		{
		  /* Restart timer for only 100ms*/
		  tv.tv_sec = 0;
		  tv.tv_usec = 100000;
		  timeout -= tv.tv_usec;
		  if(timeout > 0)
		    continue;	/* Try again later */
		}

	      /* Bad error */
	      free(buffer);
	      fprintf(stderr, "%-8.16s  Failed to read scan data : %s\n\n",
		      ifname, strerror(errno));
	      return(-2);
	    }
	  else
	    /* We have the results, go to process them */
	    break;
	}

      /* In here, check if event and event type
       * if scan event, read results. All errors bad & no reset timeout */
    }

  if(wrq.u.data.length)
    {
      struct iw_event		iwe;
      struct stream_descr	stream;
      struct iwscan_state	state = { .ap_num = 1, .val_index = 0 };
      int			ret;
      
#if 0
      /* Debugging code. In theory useless, because it's debugged ;-) */
      int	i;
      printf("Scan result %d [%02X", wrq.u.data.length, buffer[0]);
      for(i = 1; i < wrq.u.data.length; i++)
	printf(":%02X", buffer[i]);
      printf("]\n");
#endif
      printf("%-8.16s  Scan completed :\n", ifname);
      iw_init_event_stream(&stream, (char *) buffer, wrq.u.data.length);
      do
	{
	  /* Extract an event and print it */
	  ret = iw_extract_event_stream(&stream, &iwe,
					range.we_version_compiled);
	  if(ret > 0)
	    print_scanning_token(&stream, &iwe, &state,
				 &range, has_range);
	}
      while(ret > 0);
      printf("\n");
    }
  else
    printf("%-8.16s  No scan results\n", ifname);

  free(buffer);
  return(0);
}

/******************** WIRELESS EVENT CAPABILITY ********************/

static const char *	event_capa_req[] =
{
  [SIOCSIWNWID	- SIOCIWFIRST] = "Set NWID (kernel generated)",
  [SIOCSIWFREQ	- SIOCIWFIRST] = "Set Frequency/Channel (kernel generated)",
  [SIOCGIWFREQ	- SIOCIWFIRST] = "New Frequency/Channel",
  [SIOCSIWMODE	- SIOCIWFIRST] = "Set Mode (kernel generated)",
  [SIOCGIWTHRSPY - SIOCIWFIRST] = "Spy threshold crossed",
  [SIOCGIWAP	- SIOCIWFIRST] = "New Access Point/Cell address - roaming",
  [SIOCGIWSCAN	- SIOCIWFIRST] = "Scan request completed",
  [SIOCSIWESSID	- SIOCIWFIRST] = "Set ESSID (kernel generated)",
  [SIOCGIWESSID	- SIOCIWFIRST] = "New ESSID",
  [SIOCGIWRATE	- SIOCIWFIRST] = "New bit-rate",
  [SIOCSIWENCODE - SIOCIWFIRST] = "Set Encoding (kernel generated)",
  [SIOCGIWPOWER	- SIOCIWFIRST] = NULL,
};

static const char *	event_capa_evt[] =
{
  [IWEVTXDROP	- IWEVFIRST] = "Tx packet dropped - retry exceeded",
  [IWEVCUSTOM	- IWEVFIRST] = "Custom driver event",
  [IWEVREGISTERED - IWEVFIRST] = "Registered node",
  [IWEVEXPIRED	- IWEVFIRST] = "Expired node",
};

/*------------------------------------------------------------------*/
/*
 * Print the number of available transmit powers for the device
 */
static int
print_event_capa_info(int		skfd,
		      char *		ifname,
		      char *		args[],		/* Command line args */
		      int		count)		/* Args count */
{
  struct iw_range	range;
  int			cmd;

  /* Avoid "Unused parameter" warning */
  args = args; count = count;

  /* Extract range info */
  if((iw_get_range_info(skfd, ifname, &range) < 0) ||
     (range.we_version_compiled < 10))
      fprintf(stderr, "%-8.16s  no wireless event capability information.\n\n",
		      ifname);
  else
    {
#if 0
      /* Debugging ;-) */
      for(cmd = 0x8B00; cmd < 0x8C0F; cmd++)
	{
	  int idx = IW_EVENT_CAPA_INDEX(cmd);
	  int mask = IW_EVENT_CAPA_MASK(cmd);
	  printf("0x%X - %d - %X\n", cmd, idx, mask);
	}
#endif

      printf("%-8.16s  Wireless Events supported :\n", ifname);

      for(cmd = SIOCIWFIRST; cmd <= SIOCGIWPOWER; cmd++)
	{
	  int idx = IW_EVENT_CAPA_INDEX(cmd);
	  int mask = IW_EVENT_CAPA_MASK(cmd);
	  if(range.event_capa[idx] & mask)
	    printf("          0x%04X : %s\n",
		   cmd, event_capa_req[cmd - SIOCIWFIRST]);
	}
      for(cmd = IWEVFIRST; cmd <= IWEVEXPIRED; cmd++)
	{
	  int idx = IW_EVENT_CAPA_INDEX(cmd);
	  int mask = IW_EVENT_CAPA_MASK(cmd);
	  if(range.event_capa[idx] & mask)
	    printf("          0x%04X : %s\n",
		   cmd, event_capa_evt[cmd - IWEVFIRST]);
	}
      printf("\n");
    }
  return(0);
}

/************************* COMMON UTILITIES *************************/
/*
 * This section was initially written by Michael Tokarev <[e-mail]>
 * but heavily modified by me ;-)
 */

/*------------------------------------------------------------------*/
/*
 * Map command line arguments to the proper procedure...
 */
typedef struct iwlist_entry {
  const char *cmd;
  iw_enum_handler fn;
  int min_count;
  int max_count;
} iwlist_cmd;

static const struct iwlist_entry iwlist_cmds[] = {
  { "scanning",		print_scanning_info,	0, 5 },
  { "frequency",	print_freq_info,	0, 0 },
  { "channel",		print_freq_info,	0, 0 },
  { "bitrate",		print_bitrate_info,	0, 0 },
  { "rate",		print_bitrate_info,	0, 0 },
  { "encryption",	print_keys_info,	0, 0 },
  { "key",		print_keys_info,	0, 0 },
  { "power",		print_pm_info,		0, 0 },
  { "txpower",		print_txpower_info,	0, 0 },
  { "retry",		print_retry_info,	0, 0 },
  { "ap",		print_ap_info,		0, 0 },
  { "accesspoints",	print_ap_info,		0, 0 },
  { "peers",		print_ap_info,		0, 0 },
  { "event",		print_event_capa_info,	0, 0 },
  { NULL, NULL, 0, 0 },
};

/*------------------------------------------------------------------*/
/*
 * Find the most appropriate command matching the command line
 */
static inline const iwlist_cmd *
find_command(const char *	cmd)
{
  const iwlist_cmd *	found = NULL;
  int			ambig = 0;
  unsigned int		len = strlen(cmd);
  int			i;

  /* Go through all commands */
  for(i = 0; iwlist_cmds[i].cmd != NULL; ++i)
    {
      /* No match -> next one */
      if(strncasecmp(iwlist_cmds[i].cmd, cmd, len) != 0)
	continue;

      /* Exact match -> perfect */
      if(len == strlen(iwlist_cmds[i].cmd))
	return &iwlist_cmds[i];

      /* Partial match */
      if(found == NULL)
	/* First time */
	found = &iwlist_cmds[i];
      else
	/* Another time */
	if (iwlist_cmds[i].fn != found->fn)
	  ambig = 1;
    }

  if(found == NULL)
    {
      fprintf(stderr, "iwlist: unknown command `%s'\n", cmd);
      return NULL;
    }

  if(ambig)
    {
      fprintf(stderr, "iwlist: command `%s' is ambiguous\n", cmd);
      return NULL;
    }

  return found;
}

/*------------------------------------------------------------------*/
/*
 * Display help
 */
static void iw_usage(int status)
{
  FILE* f = status ? stderr : stdout;
  int i;

  fprintf(f,   "Usage: iwlist [interface] %s\n", iwlist_cmds[0].cmd);
  for(i = 1; iwlist_cmds[i].cmd != NULL; ++i)
    fprintf(f, "              [interface] %s\n", iwlist_cmds[i].cmd);
  exit(status);
}

/******************************* MAIN ********************************/

/*------------------------------------------------------------------*/
/*
 * The main !
 */
int
main(int	argc,
     char **	argv)
{
  int skfd;			/* generic raw socket desc.	*/
  char *dev;			/* device name			*/
  char *cmd;			/* command			*/
  char **args;			/* Command arguments */
  int count;			/* Number of arguments */
  const iwlist_cmd *iwcmd;

  if(argc == 1 || argc > 3)
    iw_usage(1);

  /* Those don't apply to all interfaces */
  if((argc == 2) && (!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help")))
    iw_usage(0);
  if((argc == 2) && (!strcmp(argv[1], "-v") || !strcmp(argv[1], "--version")))
    return(iw_print_version_info("iwlist"));

  if(argc == 2)
    {
      cmd = argv[1];
      dev = NULL;
      args = NULL;
      count = 0;
    }
  else
    {
      cmd = argv[2];
      dev = argv[1];
      args = argv + 3;
      count = argc - 3;
    }

  /* find a command */
  iwcmd = find_command(cmd);
  if(iwcmd == NULL)
    return 1;

  /* Check arg numbers */
  if(count < iwcmd->min_count)
    {
      fprintf(stderr, "iwlist: command `%s' needs more arguments\n", cmd);
      return 1;
    }
  if(count > iwcmd->max_count)
    {
      fprintf(stderr, "iwlist: command `%s' needs fewer arguments\n", cmd);
      return 1;
    }

  /* Create a channel to the NET kernel. */
  if((skfd = iw_sockets_open()) < 0)
    {
      perror("socket");
      return -1;
    }

  /* do the actual work */
  if (dev)
    (*iwcmd->fn)(skfd, dev, args, count);
  else
    iw_enum_devices(skfd, iwcmd->fn, args, count);

  /* Close the socket. */
  iw_sockets_close(skfd);

  return 0;
}