arm wifi ap热点功能

一、hostapd.

1.hostapd编译：

在rtl8188wifi资料包中解压wpa_supplicant_hostapd-0.8_rtw_20120803.zip，并进入hostapd源码目录：

修改Makefile文件，添加

1）CC=arm-linux-gcc

2）CFLAGS = -MMD -O2 -Wall -g

保存退出，make。编译完毕生成hostapd，将其拷贝到开发板/sbin目录下。

2.配置文件：hostap.conf：

内容如下：

#wifi接口

interface=wlan0

#wifi热点名称

ssid=rocky

#通道

channel=1

#可以默认为g

hw_mode=g

wpa=1

#密码

wpa_passphrase=123456789

#加密方式

wpa_key_mgmt=WPA-PSK

wpa_pairwise=CCMP

3.获得最佳频道的方法：

ifconfig wlan0 up

iwlist wlan0 scan

cat /proc/net/rtl819xD/wlan0/best_channel

4.开发板上设置wifi的地址为：192.168.1.1

5.开发板上启动wifi热点服务：

./hostapd hostap.conf -B

6.到此为止，wifi热点已经开启，其他设备可通过静态ip来连接这个热点。若要使用动态获取ip，则还需要开启udhcpd服务。

二、udhcpd：

1.无需再编译，由busybox中已编出。

2.TQ2440上无/var/lib/misc/udhcpd.leases这个文件，开启udhcpd服务的时候会提示错误。解决方法就是自己手动创建它。

3.启动udhcpd服务命令：

udhcpd -fS /etc/udhcpd.conf &

4.配置文件dhcpd.conf内容：

1）需要注意修改的地方

interface eth0 改为 interface wlan0

2） 注释掉：option 0x08 01020304 这一行。

3）其他参数根据实际情况去修改。

5.以下附上udhcpd.conf的内容及说明：

######################################################################################

# Sample udhcpd configuration file (/etc/udhcpd.conf)

# Values shown are defaults

# The start and end of the IP lease block

start 192.168.1.20

end 192.168.1.254

# The interface that udhcpd will use

interface wlan0

# The maximum number of leases (includes addresses reserved

# by OFFER's, DECLINE's, and ARP conflicts). Will be corrected

# if it's bigger than IP lease block, but it ok to make it

# smaller than lease block.

#max_leases 254

# The time period at which udhcpd will write out a dhcpd.leases

# file. If this is 0, udhcpd will never automatically write a

# lease file. Specified in seconds.

#auto_time 7200

# The amount of time that an IP will be reserved (leased to nobody)

# if a DHCP decline message is received (seconds)

#decline_time 3600

# The amount of time that an IP will be reserved

# if an ARP conflict occurs (seconds)

#conflict_time 3600

# How long an offered address is reserved (seconds)

#offer_time 60

# If client asks for lease below this value, it will be rounded up

# to this value (seconds)

#min_lease 60

# The location of the leases file

#lease_file /etc/udhcpd.leases

# The location of the pid file

#pidfile /var/run/udhcpd.pid

# Every time udhcpd writes a leases file, the below script will be called

#notify_file # default: no script

#notify_file dumpleases # useful for debugging

# The following are bootp specific options

# next server to use in bootstrap

#siaddr 192.168.1.22 # default: 0.0.0.0 (none)

# tftp server name

#sname zorak # default: none

# tftp file to download (e.g. kernel image)

#boot_file /var/nfs_root # default: none

# Static leases map

#static_lease 00:60:08:11:CE:4E 192.168.1.54

#static_lease 00:60:08:11:CE:3E 192.168.1.44

# The remainder of options are DHCP options and can be specified with the

# keyword 'opt' or 'option'. If an option can take multiple items, such

# as the dns option, they can be listed on the same line, or multiple

# lines.

# Examples:

opt dns 210.21.4.130 221.5.88.88

option subnet 255.255.255.0

opt router 192.168.1.2

opt wins 192.168.1.8

option dns 210.21.4.130 # appended to above DNS servers for a total of 3

option domain local

option lease 864000 # default: 10 days

# Arbitrary option in hex form:

#option 0x08 01020304 # option 8: "cookie server IP addr: 1.2.3.4"

# Currently supported options (for more info, see options.c):

#opt lease NUM

#opt subnet IP

#opt broadcast IP

#opt router IP_LIST

#opt ipttl NUM

#opt mtu NUM

#opt hostname STRING # client's hostname

#opt domain STRING # client's domain suffix

#opt search STRING_LIST # search domains

#opt nisdomain STRING

#opt timezone NUM # (localtime - UTC_time) in seconds. signed

#opt tftp STRING # tftp server name

#opt bootfile STRING # tftp file to download (e.g. kernel image)

#opt bootsize NUM # size of that file

#opt rootpath STRING # (NFS) path to mount as root fs

#opt wpad STRING

#opt serverid IP # default: server's IP

#opt message STRING # error message (udhcpd sends it on success too)

# Options specifying server(s)

#opt dns IP_LIST

#opt wins IP_LIST

#opt nissrv IP_LIST

#opt ntpsrv IP_LIST

#opt lprsrv IP_LIST

#opt swapsrv IP

# Obsolete options, no longer supported

#opt logsrv IP_LIST # 704/UDP log server (not syslog!)

#opt namesrv IP_LIST # IEN 116 name server, obsolete (August 1979!!!)

#opt cookiesrv IP_LIST # RFC 865 "quote of the day" server, rarely (never?) used

#opt timesrv IP_LIST # RFC 868 time server, rarely (never?) used

######################################################################################