对于那些使用NTLM进行身份验证的网络代理环境（即设置上除需要代理主机和端口之外还需要提供域用户和密码）来说，通过代理上网是一件头痛的事情，这主要是因为很多软件不支持NTLM验证的代理（比如目前的GIT就不能支持NTLM验证，即使在代理中指定了域帐号和密码，在连接过程中依然报： Received HTTP code 407 from proxy after CONNECT ，说明验证并未通过），如果有这样一种工具能封装NTLM验证然后对外提供普通的HTTP代理服务，那么第三方应用就可以通过配置普通的代理访问网络了，这就是Cntlm (项目官网：http://cntlm.sourceforge.net/）所要解决的问题！ 由于Cntlm也有linux版本，这意味着在linux系统上通过NTLM身份验证的网络代理也是可行的。本文原文出处: http://blog.csdn.net/bluishglc/article/details/37600773 严禁任何形式的转载，否则将委托CSDN官方维护权益！
配置
下载安装Cntlm之后，只需要修改cntlm.ini文件，提供身份认证必要的信息，然后以服务的方式启动cntlm就可以了。在cntlm.ini中有如下几个重要的配置是可能需要修改的：
-
Username - your domain/proxy account name
- Domain - the actual domain name
- Workstation - NetBIOS name of your workstation; Cntlm tries to autodetect it, but you might want to set it explicitly should dialect detection fail (see below)
- Proxy - IP address (or ping-able hostname) of your proxy; if you use several alternative proxies or know of backup ones, use this option multiple times; if one stops working, Cntlm will move on to the next
- Listen - local port number which Cntlm should bind to; the default is OK, but remember you can‘t have more than one application per port; you can use netstat to list used up ports (lines with LISTEN)
其中Listen配置项是cntlm将在本地打开的作为普通代理的端口，假如我的windows域是abc,帐号是laurence,密码是123，代理服务器是192.168.0.1：80，则cntlm.ini应该如下配置：
# # Cntlm Authentication Proxy Configuration # # NOTE: all values are parsed literally, do NOT escape spaces, # do not quote. Use 0600 perms if you use plaintext password. # Username laurence Domain abc Password 123 # NOTE: Use plaintext password only at your own risk # Use hashes instead. You can use a "cntlm -M" and "cntlm -H" # command sequence to get the right config for your environment. # See cntlm man page # Example secure config shown below. # PassLM 1AD35398BE6565DDB5C4EF70C0593492 # PassNT 77B9081511704EE852F94227CF48A793 ### Only for user ‘testuser‘, domain ‘corp-uk‘ # PassNTLMv2 D5826E9C665C37C80B53397D5C07BBCB # Specify the netbios hostname cntlm will send to the parent # proxies. Normally the value is auto-guessed. # # Workstation netbios_hostname # List of parent proxies to use. More proxies can be defined # one per line in format <proxy_ip>:<proxy_port> # Proxy 192.168.0.1:80 # List addresses you do not want to pass to parent proxies # * and ? wildcards can be used # NoProxy localhost, 127.0.0.*, 10.*, 192.168.* # Specify the port cntlm will listen on # You can bind cntlm to specific interface by specifying # the appropriate IP address also in format <local_ip>:<local_port> # Cntlm listens on 127.0.0.1:3128 by default # Listen 3128 # If you wish to use the SOCKS5 proxy feature as well, uncomment # the following option. It can be used several times # to have SOCKS5 on more than one port or on different network # interfaces (specify explicit source address for that). # # WARNING: The service accepts all requests, unless you use # SOCKS5User and make authentication mandatory. SOCKS5User # can be used repeatedly for a whole bunch of individual accounts. # #SOCKS5Proxy 8010 #SOCKS5User dave:password # Use -M first to detect the best NTLM settings for your proxy. # Default is to use the only secure hash, NTLMv2, but it is not # as available as the older stuff. # # This example is the most universal setup known to man, but it # uses the weakest hash ever. I won‘t have it‘s usage on my # conscience. :) Really, try -M first. # #Auth LM #Flags 0x06820000 # Enable to allow access from other computers # #Gateway yes # Useful in Gateway mode to allow/restrict certain IPs # Specifiy individual IPs or subnets one rule per line. # #Allow 127.0.0.1 #Deny 0/0 # GFI WebMonitor-handling plugin parameters, disabled by default # #ISAScannerSize 1024 #ISAScannerAgent Wget/ #ISAScannerAgent APT-HTTP/ #ISAScannerAgent Yum/ # Headers which should be replaced if present in the request # #Header User-Agent: Mozilla/4.0 (compatible; MSIE 5.5; Windows 98) # Tunnels mapping local port to a machine behind the proxy. # The format is <local_port>:<remote_host>:<remote_port> # #Tunnel 11443:remote.com:443
其中对于监听端口使用默认的端口3128就可以了。我们可以通过命令来验证配置是否正确：
cntlm -c /path/to/cntlm.ini -I -M http://www.baidu.com
如果能正常返回就表示各项配置都是正确的，接下就可以启动cntlm服务在后台运行了，使用命令：
net start cntlm
服务启动之后，我们就可以在第三方应用的代理配置上这样设定了：代理服务器：127.0.0.1 （即本机），代理服务器端口：3128（即cntlm.ini文件中配置的Listen端口）
日志与常见错误
cntlm绝大多数错误表现为服务无法启动，具体原因有很多，好在cntlm有较好的日志信息可以帮助我们找到问题的根源，查看cntlm日志的方法是：Start -> Settings -> Control Panel -> Administrative Tools -> Event Viewer, 然后在左侧面板的目录树中选择：Windows Logs -> Application, 再在右侧面板中配置一下过虑项，将事件源设定为cntlm就可以过滤出所有的cntlm日志了。
这里我们介绍两种可能的错误：
1. cntlm: PID XXXX: Possible duplicate cygwin1.dll: /socat-1.7.2.1/cygwin1.dll.
类似这样的错误是由于cygwin1.dll冲突引起的，有多种工具会携带自己的cygwin1.dll，如果版本不兼容就会报如上的错误，最简单的方是先移除它们。
2. cntlm: Parent proxy address missing
这是一个容易造成误导的错误，如果多数情况下并不是因为你在cntlm.ini中错误地制定了Proxy而是cntlm程序启动时根本没用找到cntlm.ini文件，造成这种问题的可能诱因之一是在安装cntlm时修改了默认的安装目录，这应该是cntlm的一个bug。不知道在启动cntlm服务的配置界面（Control Panel -> Administrative Tools -> Services）上指定-c参数是否有效，有兴趣的朋友可以尝试一下，我是按默认配置重装了cntlm解决的问题。
Cntlm安装和配置心得