第五節：安裝wpa_supplicant及wpa_supplicant其操作

概念：
     wpa_supplicant : 可用於下述"認證/加密"
     
     All security modes have been verified to work (at least complete authentication and successfully ping a wired host):
    - plaintext
    - static WEP / open system authentication
    - static WEP / shared key authentication
    - IEEE 802.1X with dynamic WEP keys
    - WPA-PSK, TKIP, CCMP, TKIP+CCMP
    - WPA-EAP, TKIP, CCMP, TKIP+CCMP
    - WPA2-PSK, TKIP, CCMP, TKIP+CCMP
    - WPA2-EAP, TKIP, CCMP, TKIP+CCMP
    
    分析： 一般使用 wpa-psk,wpa2-psk. 因為*.eap 是需要伺服器的。

    Download wpa_supplicant soft: http://w1.fi/wpa_supplicant/
    
    下載最新版本：wpa_supplicant-2.6版本。
    
    檢視README得有效資訊：
    This package may include either wpa_supplicant, hostapd, or both. See
README file respective subdirectories (wpa_supplicant/README or
hostapd/README) for more details.

    那就再看wpa_supplicant/README。
    
    由README可知，需要下載庫 openssl. 第三節我們已經安裝了。需要.config。

1. 解壓
   tar -xzf wpa_supplicant-2.6.tar.gz
   cd wpa_supplicant-2.6/wpa_supplicant
2. 編譯與安裝
   cp  deconfig .config
   修改.config，使能CONFIG_LIBNL32=y
   修改Makefile ，加上libnl 和 opnssl的標頭檔案 和 lib庫。
   
    CFLAGS += -I/home/clh/work/libnl-3.2.25/tmp/include/libnl3
    LDFLAGS += -L/home/clh/work/libnl-3.2.25/tmp/lib

    CFLAGS += -I/home/clh/work/openssl-1.0.1o/tmp/include
    LDFLAGS += -L/home/clh/work/openssl-1.0.1o/tmp/lib
    
   make CC=arm-linux-gcc
   make DESTDIR=$PWD/tmp install
3. 將生成的，複製到根檔案系統。
   cp tmp/usr/local/sbin/* /opt/rootfs/bin/     /*wpa_supplicant, wpa_cli, */

   
4. 操作
   在操作之前，檢視檔案wpa_supplicant/README。內容：Command line options
   
  usage:
  wpa_supplicant [-BddfhKLqqtuvW] [-P<pid file>] [-g<global ctrl>] \
        [-G<group>] \
        -i<ifname> -c<config file> [-C<ctrl>] [-D<driver>] [-p<driver_param>] \
        [-b<br_ifname> [-MN -i<ifname> -c<conf> [-C<ctrl>] [-D<driver>] \
        [-p<driver_param>] [-b<br_ifname>] [-m<P2P Device config file>] ...

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
  -d = increase debugging verbosity (-dd even more)
  -D = driver name (can be multiple drivers: nl80211,wext)
  -f = Log output to default log location (normally /tmp)
  -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)
  -p = driver parameters
  -P = PID file
  -q = decrease debugging verbosity (-qq even less)
  -u = enable DBus control interface
  -v = show version
  -W = wait for a control interface monitor before starting
  -M = start describing matching interface
  -N = start describing new interface
  -m = Configuration file for the P2P Device

drivers:
  nl80211 = Linux nl80211/cfg80211
  wext = Linux wireless extensions (generic)
  wired = wpa_supplicant wired Ethernet driver
  roboswitch = wpa_supplicant Broadcom switch driver
  bsd = BSD 802.11 support (Atheros, etc.)
  ndis = Windows NDIS driver

In most common cases, wpa_supplicant is started with

wpa_supplicant -B -c/etc/wpa_supplicant.conf -iwlan0

This makes the process fork into background.

The easiest way to debug problems, and to get debug log for bug
reports, is to start wpa_supplicant on foreground with debugging
enabled:

wpa_supplicant -c/etc/wpa_supplicant.conf -iwlan0 -d

If the specific driver wrapper is not known beforehand, it is possible
to specify multiple comma separated driver wrappers on the command
line. wpa_supplicant will use the first driver wrapper that is able to
initialize the interface.

wpa_supplicant -Dnl80211,wext -c/etc/wpa_supplicant.conf -iwlan0

分析：

wpa_supplicant [-BddfhKLqqtuvW] [-P<pid file>] [-g<global ctrl>] \
        [-G<group>] \
        -i<ifname> -c<config file> [-C<ctrl>] [-D<driver>] [-p<driver_param>] \
        [-b<br_ifname> [-MN -i<ifname> -c<conf> [-C<ctrl>] [-D<driver>] \
        [-p<driver_param>] [-b<br_ifname>] [-m<P2P Device config file>] ... 是命令格式
        
options ： 引數說明

在大多數常見情況下，wpa_supplicant的啟動，都是以這種方式配置的wpa_supplicant -B -c / etc / wpa_supplicant.conf -iwlan0。這種配置方式，使得wpa_supplicant執行在後臺。
若要獲取bug除錯日誌，可以這樣設定，wpa_supplicant -c / etc / wpa_supplicant.conf -iwlan0 -d。

使用:
配置可以參考examples下的。plaintext.conf, wep.conf, wpa2-eap-ccmp.conf, wpa-psk-tkip.conf，複製到/etc下，按自己需要進行修改。

mkdir -p /var/run/wpa_supplicant
① OPEN
wpa_supplicant -B -c/etc/plaintext.conf -iwlan0
wpa_cli -iwlan0 status  // 檢視狀態
ifconfig wlan0 192.168.43.88
ping 192.168.43.1

配置檔案內容為:
ctrl_interface=/var/run/wpa_supplicant
network={
        ssid="hello"
        key_mgmt=NONE
}

② WEP/WEP
wpa_supplicant -B -c/etc/wep.conf  -iwlan0
wpa_cli -iwlan0 status  // 檢視狀態
ifconfig wlan0 192.168.43.88
ping 192.168.43.1

配置檔案:
ctrl_interface=/var/run/wpa_supplicant
network={
        ssid="hello"
        key_mgmt=NONE
        wep_key0="hellogrilclh0"
        wep_tx_keyidx=0   //註釋： 表示用第幾個密碼
}

③WPA(TKIP)
wpa_supplicant -B -c/etc/wpa-psk-tkip.conf  -iwlan0
wpa_cli -iwlan0 status  // 檢視狀態
ifconfig wlan0 192.168.43.88
ping 192.168.43.1

配置檔案
ctrl_interface=/var/run/wpa_supplicant  # 一個目錄,用於wpa_supplicant和wpa_cli的socket通訊
network={
        ssid="hello"
        proto=WPA  # proto: list of accepted protocols, 可取WPA,RSN
                   # If not set, this defaults to: WPA RSN
        key_mgmt=WPA-PSK # 認證方式
                         # If not set, this defaults to: WPA-PSK WPA-EAP
        pairwise=TKIP    # If not set, this defaults to: CCMP TKIP
        group=TKIP       # If not set, this defaults to: CCMP TKIP WEP104 WEP40 
        psk="hellogrilclh0"
}

④ WPA2(AES)
wpa_supplicant -B -c/etc/wpa_wpa2.conf  -iwlan0
wpa_cli -iwlan0 status  // 檢視狀態
ifconfig wlan0 192.168.43.88
ping 192.168.43.1

配置檔案：
ctrl_interface=/var/run/wpa_supplicant
network={
        ssid="hello"
        psk="hellogrilclh0"
}

⑤ 配置檔案裡設定多個network:             //第一個沒有連線到的話，連線第二個。
ctrl_interface=/var/run/wpa_supplicant
network={
        ssid="hello"
        psk="hellogrilclh0"
}
network={
        ssid="vivo"
        psk="vivotest"
}

⑥ 訪問外網：
修改/etc/resolv.conf新增DNS:
nameserver 192.168.43.1

設定閘道器:
route add default gw 192.168.43.1

然後訪問外網
ping www.baidu.com

擴充套件：
wpa_cli可工作於"命令模式"和"互動模式" 下面是wpa_cli命令說明：

status  /*檢視當前連線狀態*/
scan    /*啟動一次wifi熱點掃描*/
scan_result  /*顯示上一次掃描的結果*/
add_network  /* 新增網路，返回一個編號 */
set_network  /* 設定網路的加密形式和ssid，祕鑰 */
select_network /* 使能網路，並且禁用其他網路 */
save_config  /* 儲存配置 */

例如：
# Configure a network using the newly added network interface:
wpa_cli -iwlan0 add_network
wpa_cli -iwlan0 set_network 0 ssid '"test"'
wpa_cli -iwlan0 set_network 0 key_mgmt WPA-PSK
wpa_cli -iwlan0 set_network 0 psk '"12345678"'
wpa_cli -iwlan0 set_network 0 pairwise TKIP
wpa_cli -iwlan0 set_network 0 group TKIP
wpa_cli -iwlan0 set_network 0 proto WPA
wpa_cli -iwlan0 enable_network 0

問題注意點： 設定板子ip的時候，和無線網路設定在一個網段。