在 ruby 中使用通过 ioctl 获取 essid作为模板，我想获取 BSSID 而不是 ESSID。但是，不是 C 开发人员，有几件事我不明白。
到目前为止我所拥有的不起作用:( ...
注意我有点困惑，因为根据 wireless.h 中的一些评论，我认为 BSSID 只能通过 ioctl设置。但是，要获取的 ioctl存在。再加上我几乎完全不了解更中间的 C 类型（结构、联合和东西；）），我根本不知道。
def _get_bssid(interface)
# Copied from wireless.h
# supposing a 16 byte address and 32 byte buffer but I'm totally
# guessing here.
iwreq = [interface, '' * 48,0].pack('a*pI')
sock = Socket.new(Socket::AF_INET, Socket::SOCK_DGRAM, 0)
# from wireless.h
# SIOCGIWAP 0x8B15 /* get access point MAC addresses */
sock.ioctl('0x8B15', iwreq) # always get an error: Can't convert string to Integer
puts iwreq.inspect
end
因此，与此同时，我正在使用 wpa_cli 方法来获取 BSSID，但我更喜欢使用 IOCTL：
def _wpa_status(interface)
wpa_data = nil
unless interface.nil?
# need to write a method to get the src_sock_path
# programmatically. Fortunately, for me
# this is going to be the correct sock path 99% of the time.
# Ideas to get programmatically would be:
# parse wpa_supplicant.conf
# check process table | grep wpa_suppl | parse arguments
src_sock_path = '/var/run/wpa_supplicant/' + interface
else
return nil
end
client_sock_path = '/var/run/hwinfo_wpa'
# open Domain socket
socket = Socket.new(Socket::AF_UNIX, Socket::SOCK_DGRAM, 0)
begin
# bind client domain socket
socket.bind(Socket.pack_sockaddr_un(client_sock_path))
# connect to server with our client socket
socket.connect(Socket.pack_sockaddr_un(src_sock_path))
# send STATUS command
socket.send('STATUS', 0)
# receive 1024 bytes (totally arbitrary value)
# split lines by \n
# store in variable wpa_data.
wpa_data = socket.recv(1024)
rescue => e
$stderr.puts 'WARN: unable to gather wpa data: ' + e.inspect
end
# close or next time we attempt to read it will fail.
socket.close
begin
# remove the domain socket file for the client
File.unlink(client_sock_path)
rescue => e
$stderr.puts 'WARN: ' + e.inspect
end
unless wpa_data.nil?
@wifis = Hash[wpa_data.split(/\n/).map\
{|line|
# first, split into pairs delimited by '='
key,value = line.split('=')
# if key is camel-humped then put space in front
# of capped letter
if key =~ /[a-z][A-Z]/
key.gsub!(/([a-z])([A-Z])/,'\\1_\\2')
end
# if key is "id" then rename it.
key.eql?('id') && key = 'wpa_id'
# fix key so that it can be used as a table name
# by replacing spaces with underscores
key.gsub!(' ','_')
# lower case it.
key.downcase!
[key,value]
}]
end
end
编辑：到目前为止，没有人能够回答这个问题。我想我还是更喜欢 wpa 方法，因为我从中获得了更多数据。也就是说，我想提出的一个问题是，如果有人使用 wpa 代码，请注意它需要升级权限才能读取wlan套接字。
编辑^2（完整代码片段）：感谢@dasup，我已经能够重构我的类以使用系统ioctls正确提取bssid 和essid。（YMMV 考虑到你的 Linux 发行版的实现、年龄和任何其他可能的不稳定因素——尽管下面的代码片段适用于 3.2 和 3.7 内核。）
require 'socket'
class Wpa
attr_accessor :essid, :bssid, :if
def initialize(interface)
@if = interface
puts 'essid: ' + _get_essid.inspect
puts 'bssid: ' + _get_bssid.inspect
end
def _get_essid
# Copied from wireless.h
iwreq = [@if, " " * 32, 32, 0 ].pack('a16pII')
sock = Socket.new(Socket::AF_INET, Socket::SOCK_DGRAM, 0)
sock.ioctl(0x8B1B, iwreq)
@essid = iwreq.unpack('@16p').pop.strip
end
def _get_bssid
# Copied from wireless.h
# supposing a 16 byte address and 32 byte buffer but I'm totally
# guessing here.
iwreq = [@if, "\0" * 32].pack('a16a32')
sock = Socket.new(Socket::AF_INET, Socket::SOCK_DGRAM, 0)
# from wireless.h
# SIOCGIWAP 0x8B15 /* get access point MAC addresses */
sock.ioctl(0x8B15, iwreq) # always get an error: Can't convert string to Integer
@bssid = iwreq.unpack('@18H2H2H2H2H2H2').join(':')
end
end
h = Wpa.new('wlan0')