NAME

Wi-Fi (802.11) wireless service

SYNOPSIS

#include <net80211/ieee80211.h>
#include <net80211/ieee80211_ioctl.h>
#include <net80211/ieee80211_proto.h>

int ioctl(int socket, int cmd, caddr_t param);

DESCRIPTION

The Wi-Fi (802.11) wireless service is a part of the TCP and UDP Server – tcpd. This service provides configuration and management of Wi-Fi interface parameters. User can do this by ioctl() function.

Wi-Fi service ioctl() commands

SIOCS80211SCAN – scan request
This command starts networks scanning procedure. If user not setup network name before scanning – stack will scan all available networks. If user setup network name, then after scan complete stack will try to connect to this network.

/*
 * scan request
 */
struct ifreq ifr;

memset(&ifr, 0, sizeof(ifr));
strcpy(ifr.ifr_name, "wifi0");
ioctl(s, SIOCS80211SCAN, (caddr_t)&ifr);

SIOCG80211ALLNODES – get the entire node cache
This command gets all networks which had been found by scan request. User can limit requesting networks number by size of array struct ieee80211_nodereq.

/*
 * get found nodes
 */
struct ieee80211_nodereq_all na;
struct ieee80211_nodereq nr[10];

memset(&na, 0, sizeof(na));
memset(&nr, 0, sizeof(nr));
na.na_node = nr;
na.na_size = sizeof(nr);

strcpy(na.na_ifname, "wifi0");
ioctl(s, SIOCG80211ALLNODES, &na);

SIOCS80211NWID – set nwid
This command sets network id (name). The name can be any text string up to 32 characters in length. The empty string allows the interface to scan all available access points.

/*
 * set nwid
 */
#define NET_NAME "network_name"
struct ifreq ifr;
struct ieee80211_nwid nwid;
int len;

memset(&ifr, 0, sizeof(ifr));
len = strlen(NET_NAME);
strcpy((char *)nwid.i_nwid, NET_NAME);
nwid.i_len = len;
ifr.ifr_data = (caddr_t)&nwid;

strcpy(ifr.ifr_name, "wifi0");
ioctl(s, SIOCS80211NWID, (caddr_t)&ifr);

SIOCG80211NWID – get nwid
This command gets network id (name). The name can be any text string up to 32 characters in length. The empty string allows the interface to scan all available access points.

/*
 * get nwid
 */
struct ifreq ifr;
struct ieee80211_nwid nwid;

memset(&ifr, 0, sizeof(ifr));
ifr.ifr_data = (caddr_t)&nwid;

strcpy(ifr.ifr_name, "wifi0");
ioctl(s, SIOCG80211NWID, (caddr_t)&ifr);

printf("nwid '%s'\n", nwid.i_nwid);

SIOCS80211CHANNEL – set network channel
This command sets network channel (radio frequency). If channel equals IEEE80211_CHAN_ANY, then interface gets channel from connected access point.

/*
 * set channel
 */
struct ieee80211chanreq channel;

channel.i_channel = 8;
strcpy(channel.i_name, "wifi0");
ioctl(s, SIOCS80211CHANNEL, (caddr_t)&channel);

SIOCG80211CHANNEL – get network channel
This command gets network channel (radio frequency).

/*
 * get channel
 */
struct ieee80211chanreq channel;

memset(&channel, 0, sizeof(channel));
strcpy(channel.i_name, "wifi0");
ioctl(s, SIOCG80211CHANNEL, (caddr_t)&channel);

if (channel.i_channel != IEEE80211_CHAN_ANY)
    printf("channel %d\n", channel.i_channel);

SIOCS80211NWKEY – set network access method and key
This command sets network access method and key (password).
Access methods:
– IEEE80211_NWKEY_OPEN: disable WEP encryption (no privacy)
– IEEE80211_NWKEY_WEP: enabled WEP encryption
The password can be any text string up to 16 characters in length.

/*
 * set nwkey
 */
#define NET_SEC_PROTO   IEEE80211_NWKEY_WEP
#define NET_KEY         "1234567890"
struct ieee80211_nwkey nwkey;
uchar keybuf[16];

memset(&nwkey, 0, sizeof(nwkey));
memset(&keybuf, 0, sizeof(keybuf));

nwkey.i_wepon = NET_SEC_PROTO;
nwkey.i_defkid = 1;

strcpy((char *)keybuf, NET_KEY);
nwkey.i_key[0].i_keylen = strlen(NET_KEY);
nwkey.i_key[0].i_keydat = keybuf;

strcpy(nwkey.i_name, "wifi0");
ioctl(s, SIOCS80211NWKEY, (caddr_t)&nwkey);

SIOCG80211NWKEY – get network access method and key
This command gets network access method and key (password).
Access methods:
– IEEE80211_NWKEY_OPEN: disable WEP encryption (no privacy)
– IEEE80211_NWKEY_WEP: enabled WEP encryption
The password can be any text string up to 16 characters in length.

/*
 * get nwkey
 */
struct ieee80211_nwkey nwkey;
uchar keybuf[16];

memset(&nwkey, 0, sizeof(nwkey));
memset(&keybuf, 0, sizeof(keybuf));

nwkey.i_key[0].i_keylen = sizeof(keybuf);
nwkey.i_key[0].i_keydat = keybuf;

strcpy(nwkey.i_name, "wifi0");
ioctl(s, SIOCG80211NWKEY, (caddr_t)&nwkey);

if (nwkey.i_wepon == IEEE80211_NWKEY_WEP)
    printf("wep key: '%s'\n", keybuf);

SIOCS80211WPAPARMS – set WPA parameters
This command enables WPA (Wi-Fi Protected Access) and sets version.
WPA versions:
– IEEE80211_WPA_PROTO_WPA1: WPA version 1
– IEEE80211_WPA_PROTO_WPA2: WPA version 2
If field wpa.i_enabled equals ‘0’, then WPA will be disable.

/*
 * set WPA version
 */
#define NET_SEC_PROTO   IEEE80211_WPA_PROTO_WPA1
struct ieee80211_wpaparams wpa;

memset(&wpa, 0, sizeof(wpa));
wpa.i_enabled = 1;
wpa.i_protos = NET_SEC_PROTO;

strcpy(wpa.i_name, "wifi0");
ioctl(s, SIOCS80211WPAPARMS, (caddr_t)&wpa);

SIOCG80211WPAPARMS – get WPA parameters
This command gets WPA state and version.
WPA versions:
– IEEE80211_WPA_PROTO_WPA1: WPA version 1
– IEEE80211_WPA_PROTO_WPA2: WPA version 2

/*
 * get WPA version
 */
struct ieee80211_wpaparams wpa;

memset(&wpa, 0, sizeof(wpa));
strcpy(wpa.i_name, "wifi0");
ioctl(s, SIOCG80211WPAPARMS, (caddr_t)&wpa);

if (wpa.i_enabled)
{
    if (wpa.i_protos == IEEE80211_WPA_PROTO_WPA1)
        printf("wpa1");
    else if (wpa.i_protos == IEEE80211_WPA_PROTO_WPA2)
        printf("wpa2");
}

SIOCS80211WPAPSK – set PSK
This command sets network PSK (Pre-Shared Key) for WPA. The key can be any text string up to 32 characters in length.

/*
 * set PSK key
 */
#define NET_KEY         "1234567890"
struct ieee80211_wpapsk psk;

memset(&psk, 0, sizeof(psk));
psk.i_enabled = 1;
strcpy((char *)psk.i_psk, NET_KEY);

strcpy(psk.i_name, "wifi0");
ioctl(s, SIOCS80211WPAPSK, (caddr_t)&psk);

SIOCG80211WPAPSK – get PSK
This command gets network PSK (Pre-Shared Key) for WPA. The key can be any text string up to 32 characters in length.

/*
 * get PSK key
 */
struct ieee80211_wpapsk psk;

memset(&psk, 0, sizeof(psk));
strcpy(psk.i_name, "wifi0");
ioctl(s, SIOCS80211WPAPSK, (caddr_t)&psk);

if (psk.i_enabled == 1)
    printf("psk: '%s'\n", psk.i_psk);

SIOCG80211STATE – get current state
This command gets interface current state.
Wi-Fi interface states:
– IEEE80211_S_INIT: default state
– IEEE80211_S_SCAN: scanning
– IEEE80211_S_AUTH: try to authenticate
– IEEE80211_S_ASSOC: try to associate
– IEEE80211_S_RUN: associated

/*
 * get state
 */
struct ifreq ifr;
enum ieee80211_state ic_state;

memset(&ifr, 0, sizeof(ifr));
memset(&ic_state, 0, sizeof(ic_state));
ifr.ifr_data = (caddr_t)&ic_state;

strcpy(ifr.ifr_name, "wifi0");
ioctl(s, SIOCG80211STATE, (caddr_t)&ifr);

SIOCGIFMEDIA – get interface media state
This command gets interface media activity state. The command not concern to Wi-Fi service directly but allow check network state.
Interface media activity bits:
– IFM_AVALID: active bit valid
– IFM_ACTIVE: interface attached to working net

/*
 * get media activity
 */
struct ifmediareq ifmr;

memset(&ifmr, 0, sizeof(ifmr));
strcpy(ifmr.ifm_name, "wifi0");
ioctl(s, SIOCGIFMEDIA, (caddr_t)&ifmr);

if (ifmr.ifm_status & IFM_AVALID)
{
    if (ifmr.ifm_status & IFM_ACTIVE)
        printf("active\n");
    else
        printf("no network\n");
}
else
    printf("status unknown\n");

NOTES

There are a Wi-Fi demo projects available for the Unison and DSPnano which is found in installdir/demo.

SEE ALSO

tcpd, socket(), ioctl()