iwlib.c

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

/*
 *	Wireless Tools
 *
 *		Jean II - HPLB 97->99 - HPL 99->04
 *
 * Common subroutines to all the wireless tools...
 *
 * This file is released under the GPL license.
 *     Copyright (c) 1997-2004 Jean Tourrilhes <[e-mail]>
 */

/***************************** INCLUDES *****************************/

#include "iwlib.h"		/* Header */

/************************ CONSTANTS & MACROS ************************/

/*
 * Constants fof WE-9->15
 */
#define IW15_MAX_FREQUENCIES	16
#define IW15_MAX_BITRATES	8
#define IW15_MAX_TXPOWER	8
#define IW15_MAX_ENCODING_SIZES	8
#define IW15_MAX_SPY		8
#define IW15_MAX_AP		8

/****************************** TYPES ******************************/

/*
 *	Struct iw_range up to WE-15
 */
struct	iw15_range
{
	__u32		throughput;
	__u32		min_nwid;
	__u32		max_nwid;
	__u16		num_channels;
	__u8		num_frequency;
	struct iw_freq	freq[IW15_MAX_FREQUENCIES];
	__s32		sensitivity;
	struct iw_quality	max_qual;
	__u8		num_bitrates;
	__s32		bitrate[IW15_MAX_BITRATES];
	__s32		min_rts;
	__s32		max_rts;
	__s32		min_frag;
	__s32		max_frag;
	__s32		min_pmp;
	__s32		max_pmp;
	__s32		min_pmt;
	__s32		max_pmt;
	__u16		pmp_flags;
	__u16		pmt_flags;
	__u16		pm_capa;
	__u16		encoding_size[IW15_MAX_ENCODING_SIZES];
	__u8		num_encoding_sizes;
	__u8		max_encoding_tokens;
	__u16		txpower_capa;
	__u8		num_txpower;
	__s32		txpower[IW15_MAX_TXPOWER];
	__u8		we_version_compiled;
	__u8		we_version_source;
	__u16		retry_capa;
	__u16		retry_flags;
	__u16		r_time_flags;
	__s32		min_retry;
	__s32		max_retry;
	__s32		min_r_time;
	__s32		max_r_time;
	struct iw_quality	avg_qual;
};

/*
 * Union for all the versions of iwrange.
 * Fortunately, I mostly only add fields at the end, and big-bang
 * reorganisations are few.
 */
union	iw_range_raw
{
	struct iw15_range	range15;	/* WE 9->15 */
	struct iw_range		range;		/* WE 16->current */
};

/*
 * Offsets in iw_range struct
 */
#define iwr15_off(f)	( ((char *) &(((struct iw15_range *) NULL)->f)) - \
			  (char *) NULL)
#define iwr_off(f)	( ((char *) &(((struct iw_range *) NULL)->f)) - \
			  (char *) NULL)

/**************************** VARIABLES ****************************/

/* Modes as human readable strings */
const char * const iw_operation_mode[] = { "Auto",
					"Ad-Hoc",
					"Managed",
					"Master",
					"Repeater",
					"Secondary",
					"Monitor" };

/* Disable runtime version warning in iw_get_range_info() */
int	iw_ignore_version = 0;

/************************ SOCKET SUBROUTINES *************************/

/*------------------------------------------------------------------*/
/*
 * Open a socket.
 * Depending on the protocol present, open the right socket. The socket
 * will allow us to talk to the driver.
 */
int
iw_sockets_open(void)
{
  static const int families[] = {
    AF_INET, AF_IPX, AF_AX25, AF_APPLETALK
  };
  unsigned int	i;
  int		sock;

  /*
   * Now pick any (exisiting) useful socket family for generic queries
   * Note : don't open all the socket, only returns when one matches,
   * all protocols might not be valid.
   * Workaround by Jim Kaba <[e-mail]>
   * Note : in 99% of the case, we will just open the inet_sock.
   * The remaining 1% case are not fully correct...
   */

  /* Try all families we support */
  for(i = 0; i < sizeof(families)/sizeof(int); ++i)
    {
      /* Try to open the socket, if success returns it */
      sock = socket(families[i], SOCK_DGRAM, 0);
      if(sock >= 0)
	return sock;
  }

  return -1;
}

/*------------------------------------------------------------------*/
/*
 * Extract the interface name out of /proc/net/wireless or /proc/net/dev.
 */
static inline char *
iw_get_ifname(char *	name,	/* Where to store the name */
	      int	nsize,	/* Size of name buffer */
	      char *	buf)	/* Current position in buffer */
{
  char *	end;

  /* Skip leading spaces */
  while(isspace(*buf))
    buf++;

#ifndef IW_RESTRIC_ENUM
  /* Get name up to the last ':'. Aliases may contain ':' in them,
   * but the last one should be the separator */
  end = strrchr(buf, ':');
#else
  /* Get name up to ": "
   * Note : we compare to ": " to make sure to process aliased interfaces
   * properly. Doesn't work on /proc/net/dev, because it doesn't guarantee
   * a ' ' after the ':'*/
  end = strstr(buf, ": ");
#endif

  /* Not found ??? To big ??? */
  if((end == NULL) || (((end - buf) + 1) > nsize))
    return(NULL);

  /* Copy */
  memcpy(name, buf, (end - buf));
  name[end - buf] = '\0';

  /* Return value currently unused, just make sure it's non-NULL */
  return(end);
}

/*------------------------------------------------------------------*/
/*
 * Enumerate devices and call specified routine
 * The new way just use /proc/net/wireless, so get all wireless interfaces,
 * whether configured or not. This is the default if available.
 * The old way use SIOCGIFCONF, so get only configured interfaces (wireless
 * or not).
 */
void
iw_enum_devices(int		skfd,
		iw_enum_handler	fn,
		char *		args[],
		int		count)
{
  char		buff[1024];
  FILE *	fh;
  struct ifconf ifc;
  struct ifreq *ifr;
  int		i;

#ifndef IW_RESTRIC_ENUM
  /* Check if /proc/net/dev is available */
  fh = fopen(PROC_NET_DEV, "r");
#else
  /* Check if /proc/net/wireless is available */
  fh = fopen(PROC_NET_WIRELESS, "r");
#endif

  if(fh != NULL)
    {
      /* Success : use data from /proc/net/wireless */

      /* Eat 2 lines of header */
      fgets(buff, sizeof(buff), fh);
      fgets(buff, sizeof(buff), fh);

      /* Read each device line */
      while(fgets(buff, sizeof(buff), fh))
	{
	  char	name[IFNAMSIZ + 1];
	  char *s;

	  /* Skip empty or almost empty lines. It seems that in some
	   * cases fgets return a line with only a newline. */
	  if((buff[0] == '\0') || (buff[1] == '\0'))
	    continue;

	  /* Extract interface name */
	  s = iw_get_ifname(name, sizeof(name), buff);

	  if(!s)
	    {
	      /* Failed to parse, complain and continue */
#ifndef IW_RESTRIC_ENUM
	      fprintf(stderr, "Cannot parse " PROC_NET_DEV "\n");
#else
	      fprintf(stderr, "Cannot parse " PROC_NET_WIRELESS "\n");
#endif
	    }
	  else
	    /* Got it, print info about this interface */
	    (*fn)(skfd, name, args, count);
	}

      fclose(fh);
    }
  else
    {
      /* Get list of configured devices using "traditional" way */
      ifc.ifc_len = sizeof(buff);
      ifc.ifc_buf = buff;
      if(ioctl(skfd, SIOCGIFCONF, &ifc) < 0)
	{
	  fprintf(stderr, "SIOCGIFCONF: %s\n", strerror(errno));
	  return;
	}
      ifr = ifc.ifc_req;

      /* Print them */
      for(i = ifc.ifc_len / sizeof(struct ifreq); --i >= 0; ifr++)
	(*fn)(skfd, ifr->ifr_name, args, count);
    }
}

/*********************** WIRELESS SUBROUTINES ************************/

/*------------------------------------------------------------------*/
/*
 * Extract WE version number from /proc/net/wireless
 * In most cases, you really want to get version information from
 * the range info (range->we_version_compiled), see below...
 *
 * If we have WE-16 and later, the WE version is available at the
 * end of the header line of the file.
 * For version prior to that, we can only detect the change from
 * v11 to v12, so we do an approximate job. Fortunately, v12 to v15
 * are highly binary compatible (on the struct level).
 */
int
iw_get_kernel_we_version(void)
{
  char		buff[1024];
  FILE *	fh;
  char *	p;
  int		v;

  /* Check if /proc/net/wireless is available */
  fh = fopen(PROC_NET_WIRELESS, "r");

  if(fh == NULL)
    {
      fprintf(stderr, "Cannot read " PROC_NET_WIRELESS "\n");
      return(-1);
    }

  /* Read the first line of buffer */
  fgets(buff, sizeof(buff), fh);

  if(strstr(buff, "| WE") == NULL)
    {
      /* Prior to WE16, so explicit version not present */

      /* Black magic */
      if(strstr(buff, "| Missed") == NULL)
	v = 11;
      else
	v = 15;
      fclose(fh);
      return(v);
    }

  /* Read the second line of buffer */
  fgets(buff, sizeof(buff), fh);

  /* Get to the last separator, to get the version */
  p = strrchr(buff, '|');
  if((p == NULL) || (sscanf(p + 1, "%d", &v) != 1))
    {
      fprintf(stderr, "Cannot parse " PROC_NET_WIRELESS "\n");
      fclose(fh);
      return(-1);
    }

  fclose(fh);
  return(v);
}

/*------------------------------------------------------------------*/
/*
 * Print the WE versions of the interface.
 */
static int
print_iface_version_info(int	skfd,
			 char *	ifname,
			 char *	args[],		/* Command line args */
			 int	count)		/* Args count */
{
  struct iwreq		wrq;
  char			buffer[sizeof(iwrange) * 2];	/* Large enough */
  struct iw_range *	range;

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

  /* If no wireless name : no wireless extensions.
   * This enable us to treat the SIOCGIWRANGE failure below properly. */
  if(iw_get_ext(skfd, ifname, SIOCGIWNAME, &wrq) < 0)
    return(-1);

  /* Cleanup */
  memset(buffer, 0, sizeof(buffer));

  wrq.u.data.pointer = (caddr_t) buffer;
  wrq.u.data.length = sizeof(buffer);
  wrq.u.data.flags = 0;
  if(iw_get_ext(skfd, ifname, SIOCGIWRANGE, &wrq) < 0)
    {
      /* Interface support WE (see above), but not IWRANGE */
      fprintf(stderr, "%-8.16s  Driver has no Wireless Extension version information.\n\n", ifname);
      return(0);
    }

  /* Copy stuff at the right place, ignore extra */
  range = (struct iw_range *) buffer;

  /* For new versions, we can check the version directly, for old versions
   * we use magic. 300 bytes is a also magic number, don't touch... */
  if(wrq.u.data.length >= 300)
    {
      /* Version is always at the same offset, so it's ok */
      printf("%-8.16s  Recommend Wireless Extension v%d or later,\n",
	     ifname, range->we_version_source);
      printf("          Currently compiled with Wireless Extension v%d.\n\n",
	     range->we_version_compiled);
    }
  else
    {
      fprintf(stderr, "%-8.16s  Wireless Extension version too old.\n\n",
		      ifname);
    }


  return(0);
}

/*------------------------------------------------------------------*/
/*
 * Print the WE versions of the tools.
 */
int
iw_print_version_info(const char *	toolname)
{
  int		skfd;			/* generic raw socket desc.	*/
  int		we_kernel_version;

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

  /* Information about the tools themselves */
  if(toolname != NULL)
    printf("%-8.16s  Wireless-Tools version %d\n", toolname, WT_VERSION);
  printf("          Compatible with Wireless Extension v11 to v%d.\n\n",
	 WE_VERSION);

  /* Get version from kernel */
  we_kernel_version = iw_get_kernel_we_version();
  /* Only version >= 16 can be verified, other are guessed */
  if(we_kernel_version > 15)
    printf("Kernel    Currently compiled with Wireless Extension v%d.\n\n",
	   we_kernel_version);

  /* Version for each device */
  iw_enum_devices(skfd, &print_iface_version_info, NULL, 0);

  iw_sockets_close(skfd);

  return 0;
}

/*------------------------------------------------------------------*/
/*
 * Get the range information out of the driver
 */
int
iw_get_range_info(int		skfd,
		  const char *	ifname,
		  iwrange *	range)
{
  struct iwreq		wrq;
  char			buffer[sizeof(iwrange) * 2];	/* Large enough */
  union iw_range_raw *	range_raw;

  /* Cleanup */
  bzero(buffer, sizeof(buffer));

  wrq.u.data.pointer = (caddr_t) buffer;
  wrq.u.data.length = sizeof(buffer);
  wrq.u.data.flags = 0;
  if(iw_get_ext(skfd, ifname, SIOCGIWRANGE, &wrq) < 0)
    return(-1);

  /* Point to the buffer */
  range_raw = (union iw_range_raw *) buffer;

  /* For new versions, we can check the version directly, for old versions
   * we use magic. 300 bytes is a also magic number, don't touch... */
  if(wrq.u.data.length < 300)
    {
      /* That's v10 or earlier. Ouch ! Let's make a guess...*/
      range_raw->range.we_version_compiled = 9;
    }

  /* Check how it needs to be processed */
  if(range_raw->range.we_version_compiled > 15)
    {
      /* This is our native format, that's easy... */
      /* Copy stuff at the right place, ignore extra */
      memcpy((char *) range, buffer, sizeof(iwrange));
    }
  else
    {
      /* Zero unknown fields */
      bzero((char *) range, sizeof(struct iw_range));

      /* Initial part unmoved */
      memcpy((char *) range,
	     buffer,
	     iwr15_off(num_channels));
      /* Frequencies pushed futher down towards the end */
      memcpy((char *) range + iwr_off(num_channels),
	     buffer + iwr15_off(num_channels),
	     iwr15_off(sensitivity) - iwr15_off(num_channels));
      /* This one moved up */
      memcpy((char *) range + iwr_off(sensitivity),
	     buffer + iwr15_off(sensitivity),
	     iwr15_off(num_bitrates) - iwr15_off(sensitivity));
      /* This one goes after avg_qual */
      memcpy((char *) range + iwr_off(num_bitrates),
	     buffer + iwr15_off(num_bitrates),
	     iwr15_off(min_rts) - iwr15_off(num_bitrates));
      /* Number of bitrates has changed, put it after */
      memcpy((char *) range + iwr_off(min_rts),
	     buffer + iwr15_off(min_rts),
	     iwr15_off(txpower_capa) - iwr15_off(min_rts));
      /* Added encoding_login_index, put it after */
      memcpy((char *) range + iwr_off(txpower_capa),
	     buffer + iwr15_off(txpower_capa),