本文介绍了嵌入式ARM-Linux上的常用运用程序wpa_supplicant(以及wpa_supplicant依靠的libnl和openssl)的编译、装备和运转运用，iw、hostapd等运用的编译和运用。

wpa_supplicant编译和装备运转

从https://w1.fi/wpa_supplicant/（git地址git://w1.fi/hostap.git）下载最新的wpa_supplicant源码压缩包，现在最新的为版别2.5. wpa_supplicant的编译依靠于openssl和libnl库（Netlink Protocol Library Suite (libnl)），openssl是ssl协议的开源库(OpenSSL, Secure Sockets Layer (SSL v2/v3) Transport Layer Security (TLS v1)).（压缩包地址：http://www.openssl.org/source/，Git地址：https://github.com/openssl/openssl），libnl是网络相关的库（压缩包地址：http://www.infradead.org/~tgr/libnl/，Git地址 ：http://git.infradead.org/users/tgr/libnl.git）。

编译libnl

解压源代码包。进入libnl目录，履行./configure装备编译环境；履行make进行编译

然后履行sudo make install，libnl.so会被装置至/usr/local/lib/目录下，相应的头文件也会被copy到/usr/local/include/netlink下。

假如报出编译过错：“../include/netlink_local.h:218:error ULONG_MAX undeclared”，咱们在对应文件增加一个头文件#include即可解决问题；

编译openssl

进入openssl目录，./config shared #一定要加shared,不然编译出来的是静态库。履行make进行编译，完结后履行make install，编译好的openssl库和头文件等被装置在目录/usr/local/ssl下

If you want to disable installing the static libraries, use this sed:

Now, as therootuser:

编译wpa_supplicant

增加修正装备文件

进入wpa_supplicant/wpa_supplicant目录，履行cp defconfig .config复制生成编译装备，然后修正装备文件.config，

#假如挑选的不是libnl的1.0版别，需求依据libnl的版别翻开下面的选项

CONFIG_LIBNL32=y

CONFIG_LIBNL20=y挑选libnl的版别

#增加openssl和libnl的头文件和库文件目录，更新编译链接环境变量

CFLAGS += -I/usr/local/ssl/include
CFLAGS += -I/usr/local/include/ libnl3
CFLAGS += -I/usr/local/include/netlink
LIBS += -L/usr/local/ssl/lib
LIBS += -L/usr/local/lib
LIBS_p += -L/usr/local/ssl/lib#不加此行，编wpa_passphrase犯错。

cp defconfig .config

make CC=arm-linux-gnueabi-gcc

make install DESTDIR=/home/export/rootfs

履行make进行编译

成功后生成三个方针文件wpa_supplicant, wpa_cli, wpa_passphrase，至此编译完结。

运转wpa_supplicant

需求确保libssl库在咱们的查找途径里，不然不做处理，会呈现找不到libnl, ssl和crypto库的过错。

./wpa_supplicant

./wpa_supplicant: error while loading shared libraries: libssl.so.1.1.0: cannot open shared object file: No such file or directory

将/usr/local/ssl/lib下的libssl.so.x.x.x和libcrypto.so.xxx复制到/lib目录下即可，或许：export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/ssl/lib，或许在/etc/ld.so.conf文件中增加库的查找途径。(或许在/etc/ld.so.conf.d下新建一个.conf文件，将查找途径一行一个参加).

cp /usr/arm-linux-gnueabi/lib/libnl.so.1.1.4 /home/export/rootfs/lib/

cp /usr/arm-linux-gnueabi/lib/libcrypto.so.1.0.0 /home/export/rootfs/lib/

cp /usr/arm-linux-gnueabi/lib/libssl.so.1.0.0 /home/export/rootfs/lib/

装备wpa_supplicant

wpa_supplicant runs as a daemon and requires a configuration file. Create a file called /etc/wpa_supplicant.conf with the following contents:

network={

ssid=”MySSID”

key_mgmt=WPA-PSK

proto=RSN

pairwise=CCMP TKIP

psk=”MyPassPhrase”

}

The above file works with both WPA (TKIP) and WPA2 (CCMP/AES). Please insert your access point name at MySSID and your pass phrase at MyPassPhase.

Once configured, wpa_supplicant can be started using:

wpa_supplicant -B -i wlan0 -c /etc/wpa_supplicant.conf

编译过错处理

Error#1

#######################################################################
CC ../src/drivers/driver_wired.c
../src/drivers/driver_nl80211.c:25:31: fatal error: netlink/genl/genl.h: No such file or directory
compilation terminated.
make: *** [../src/drivers/driver_nl80211.o] Error 1
#######################################################################

Solution #1
sudo apt-get -y install libssl-dev libnl-3-dev
echo CFLAGS +=-I/usr/include/libnl3/ >> .config

make

Error#2
../src/drivers/driver_nl80211.c:95:9: warning: passing argument 1 of ‘genl_ctrl_alloc_cache’ from incompatible pointer type [enabled by default]
/usr/include/libnl3/netlink/genl/ctrl.h:25:14: note: expected ‘struct nl_sock *’ but argument is of type ‘struct nl_handle *’
../src/drivers/driver_nl80211.c:95:9: error: too few arguments to function ‘genl_ctrl_alloc_cache’
/usr/include/libnl3/netlink/genl/ctrl.h:25:14: note: declared here

Solution #2

sudo apt-get install libnl-genl-3-dev
echo CONFIG_LIBNL32=y >> .config

make
Usage

usage:
wpa_supplicant [-BddhKLqqtvW] [-P] [-g] \
[-G] \
-i -c [-C] [-D] [-p] \
[-b] [-e] \
[-o] [-O] \
[-N -i -c [-C] [-D] \
[-p] [-b] [-I] …]

drivers:
nl80211 = Linux nl80211/cfg80211
wext = Linux wireless extensions (generic)
wired = Wired Ethernet driver
options:
-b = optional bridge interface name
-B = run daemon in the background
-c = Configuration file
-C = ctrl_interface parameter (only used if -c is not)
-i = interface name
-I = additional configuration file
-d = increase debugging verbosity (-dd even more)
-D = driver name (can be multiple drivers: nl80211,wext)
-e = entropy file
-g = global ctrl_interface
-G = global ctrl_interface group
-K = include keys (passwords, etc.) in debug output
-t = include timestamp in debug messages
-h = show this help text
-L = show license (BSD)
-o = override driver parameter for new interfaces
-O = override ctrl_interface parameter for new interfaces
-p = driver parameters
-P = PID file
-q = decrease debugging verbosity (-qq even less)
-v = show version
-W = wait for a control interface monitor before starting
-N = start describing new interface
example:
wpa_supplicant -Dnl80211 -iwlan0 -c/etc/wpa_supplicant.conf

wpa_cli [-pctrl sockets>] [-i] [-hvB] [-a] \
[-P] [-g] [-G] [command..]
-h = help (show this usage text)
-v = shown version information
-a = run in daemon mode executing the action file based on events from
wpa_supplicant
-B = run a daemon in the background
default path: /var/run/wpa_supplicant
default interface: first interface found in socket path
commands:
status [verbose] = get current WPA/EAPOL/EAP status
ifname = get current interface name
ping = pings wpa_supplicant
relog = re-open log-file (allow rolling logs)
note = add a note to wpa_supplicant debug log
mib = get MIB variables (dot1x, dot11)
help [command] = show usage help
interface [ifname] = show interfaces/select interface
level = change debug level
license = show full wpa_cli license
quit = exit wpa_cli
set = set variables (shows list of variables when run without arguments)
get = get information
logon = IEEE 802.1X EAPOL state machine logon
logoff = IEEE 802.1X EAPOL state machine logoff
pmksa = show PMKSA cache
reassociate = force reassociation
preauthenticate = force preauthentication
identity = configure identity for an SSID
password = configure password for an SSID
new_password = change password for an SSID
pin = configure pin for an SSID
otp = configure one-time-password for an SSID
passphrase = configure private key passphrase
for an SSID
sim = report SIM operation result
bssid = set preferred BSSID for an SSID
blacklist = add a BSSID to the blacklist
blacklist clear = clear the blacklist
blacklist = display the blacklist
log_level [] = update the log level/timestamp
log_level = display the current log level and log options
list_networks = list configured networks
select_network = select a network (disable others)
enable_network = enable a network
disable_network = disable a network
add_network = add a network
remove_network = remove a network
set_network = set network variables (shows
list of variables when run without arguments)
get_network = get network variables
list_creds = list configured credentials
add_cred = add a credential
remove_cred = remove a credential
set_cred = set credential variables
save_config = save the current configuration
disconnect = disconnect and wait for reassociate/reconnect command before
connecting
reconnect = like reassociate, but only takes effect if already disconnected
scan = request new BSS scan
scan_results = get latest scan results
bss < | > = get detailed scan result info
get_capability = get capabilies
reconfigure = force wpa_supplicant to re-read its configuration file
terminate = terminate wpa_supplicant
interface_add
= adds new interface, all parameters but
are optional
interface_remove = removes the interface
interface_list = list available interfaces
ap_scan = set ap_scan parameter
scan_interval = set scan_interval parameter (in seconds)
bss_expire_age = set BSS expiration age parameter
bss_expire_count = set BSS expiration scan count parameter
bss_flush = set BSS flush age (0 by default)
stkstart = request STK negotiation with
ft_ds = request over-the-DS FT with
wps_pbc [BSSID] = start Wi-Fi Protected Setup: Push Button Configuration
wps_pin [PIN] = start WPS PIN method (returns PIN, if not hardcoded)
wps_check_pin = verify PIN checksum
wps_cancel Cancels the pending WPS operation
wps_reg = start WPS Registrar to configure an AP
wps_ap_pin [params..] = enable/disable AP PIN
wps_er_start [IP address] = start Wi-Fi Protected Setup External Registrar
wps_er_stop = stop Wi-Fi Protected Setup External Registrar
wps_er_pin = add an Enrollee PIN to External Registrar
wps_er_pbc = accept an Enrollee PBC using External Registrar
wps_er_learn = learn AP configuration
wps_er_set_config = set AP configuration for enrolling
wps_er_config = configure AP
ibss_rsn = request RSN authentication with in IBSS
sta = get information about an associated station (AP)
all_sta = get information about all associated stations (AP)
deauthenticate = deauthenticate a station
disassociate = disassociate a station
chan_switch [sec_channel_offset=] [center_freq1=] [center_freq2=] [bandwidth=] [blocktx] [ht|vht] = CSA parameters
suspend = notification of suspend/hibernate
resume = notification of resume/thaw
drop_sa = drop SA without deauth/disassoc (test command)
roam = roam to the specified BSS
p2p_find [timeout] [type=*] = find P2P Devices for up-to timeout seconds
p2p_stop_find = stop P2P Devices search
p2p_connect <“pbc”|PIN> [ht40] = connect to a P2P Device
p2p_listen [timeout] = listen for P2P Devices for up-to timeout seconds
p2p_group_remove = remove P2P group interface (terminate group if GO)
p2p_group_add [ht40] = add a new P2P group (local end as GO)
p2p_prov_disc = request provisioning discovery
p2p_get_passphrase = get the passphrase for a group (GO only)
p2p_serv_disc_req = schedule service discovery request
p2p_serv_disc_cancel_req = cancel pending service discovery request
p2p_serv_disc_resp

ctrl_interface=/var/run/wpa_supplicantctrl_interface_group=0eapol_version=1# ap_scan=2 was the one for me you may try 0 or 1 indstead of 2ap_scan=2fast_reauth=1network={ssid="my_network"proto=WPAkey_mgmt=WPA-PSKpairwise=TKIPgroup=TKIPpsk="secret_password"}

ctrl_interface=/var/run/wpa_supplicantctrl_interface_group=0ap_scan=1network={ssid="my_network"proto=RSNkey_mgmt=WPA-PSKpairwise=CCMP TKIPgroup=CCMP TKIPpsk="secret_password"}

##net#modules=( "wpa_supplicant" )wpa_supplicant_ath0="-Dmadwifi"modules=( "wpa_supplicant" )wpa_timeout_ath0=60config_ath0=(" netmask 255.255.255.0")routes_ath0=("default gw ")