⭐ 欢迎来到虫虫下载站！ | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站
📤 上传资源

📄 00000030.htm

📁 一份很好的linux入门资料
💻 HTM
📖 第 1 页 / 共 5 页
字号:
🔍
12345 
<HTML><HEAD>  <TITLE>BBS水木清华站∶精华区</TITLE></HEAD><BODY><CENTER><H1>BBS水木清华站∶精华区</H1></CENTER>发信人:&nbsp;Numb&nbsp;(麻木),&nbsp;信区:&nbsp;Linux&nbsp;<BR>标&nbsp;&nbsp;题:&nbsp;FreeBSD&nbsp;Security&nbsp;HOWTO&nbsp;<BR>发信站:&nbsp;BBS&nbsp;水木清华站&nbsp;(Sun&nbsp;Dec&nbsp;20&nbsp;05:14:30&nbsp;1998)&nbsp;<BR>&nbsp;<BR>#&nbsp;<BR>#&nbsp;This&nbsp;HOW-TO&nbsp;is&nbsp;maintained&nbsp;by&nbsp;Jan&nbsp;Koum&nbsp;(<A HREF="mailto:jkb@best.com)">jkb@best.com)</A>&nbsp;<BR>#&nbsp;Please&nbsp;mail&nbsp;me&nbsp;any&nbsp;additions,&nbsp;comments,&nbsp;suggestions,&nbsp;etc.&nbsp;<BR>#&nbsp;<BR>#&nbsp;Chinese&nbsp;Version&nbsp;is&nbsp;translated&nbsp;by&nbsp;<BR>#&nbsp;Clive&nbsp;Lin&nbsp;&lt;<A HREF="mailto:clive@cirx.org>">clive@cirx.org></A>&nbsp;(isomer&nbsp;as&nbsp;well)&nbsp;<BR>#&nbsp;Thanks&nbsp;for&nbsp;MTV&nbsp;channel&nbsp;when&nbsp;I'm&nbsp;translating,&nbsp;and&nbsp;StarCraft&nbsp;game&nbsp;for&nbsp;giving&nbsp;<BR>#&nbsp;me&nbsp;some&nbsp;entertainment&nbsp;when&nbsp;I'm&nbsp;tired.&nbsp;<BR>#&nbsp;Special&nbsp;thanks&nbsp;to:&nbsp;<BR>#&nbsp;Winggy&nbsp;&lt;<A HREF="mailto:wing@cc.nsysu.edu.tw>">wing@cc.nsysu.edu.tw></A>&nbsp;<BR>#&nbsp;for&nbsp;translation&nbsp;and&nbsp;correction&nbsp;help.&nbsp;<BR>#&nbsp;$Id:&nbsp;cfbhow2,v&nbsp;1.71&nbsp;1998/11/04&nbsp;21:07:49&nbsp;clive&nbsp;Exp&nbsp;$&nbsp;<BR>#&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;FREEBSD&nbsp;SECURITY&nbsp;HOW-TO&nbsp;<BR>o&nbsp;前言&nbsp;<BR>&nbsp;&nbsp;o&nbsp;这份&nbsp;HOW-TO&nbsp;是必要的吗?&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;FreeBSD&nbsp;是一个非常安全的作业系统。也正因为它的&nbsp;source&nbsp;code&nbsp;是可以免费的取得,&nbsp;<BR>&nbsp;&nbsp;这个&nbsp;OS&nbsp;长久以来不断的有人改进加强。尽管&nbsp;FreeBSD&nbsp;一出厂就非常安全,&nbsp;但是仍然&nbsp;<BR>&nbsp;&nbsp;有更多加强安全性的措施,&nbsp;来满足&quot;偏执狂&quot;的你&nbsp;:)&nbsp;这份&nbsp;HOW-TO&nbsp;会教你一些步骤,&nbsp;以&nbsp;<BR>&nbsp;&nbsp;更加强你机器的整体安全。&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;o&nbsp;这份文件会说明&nbsp;tripwire,&nbsp;tcp_wrappers,&nbsp;cops,&nbsp;satan,&nbsp;和其它的工具吗?&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;除了&nbsp;SSH&nbsp;之外,&nbsp;不会。这是一份针对&nbsp;FreeBSD&nbsp;的文件&nbsp;-&nbsp;除此之外,&nbsp;已经有很多文件&nbsp;<BR>&nbsp;&nbsp;说明上述的工具了。目前呢,&nbsp;我只想关心的是关於&nbsp;BSD&nbsp;的部份。&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;o&nbsp;谁要读这份&nbsp;HOW-TO?&nbsp;<BR>&nbsp;&nbsp;任何想让他的系统更安全的人。这份&nbsp;HOW-TO&nbsp;包含了一些很基本的步骤,&nbsp;和某些很复杂&nbsp;<BR>&nbsp;&nbsp;的步骤。如果你有任何的疑问,&nbsp;或者想要加以补充,&nbsp;请&nbsp;eMail&nbsp;到维护人&nbsp;<A HREF="mailto:jkb@best.com">jkb@best.com</A>&nbsp;<BR>&nbsp;&nbsp;又,&nbsp;尽管大部份的内容是针对&nbsp;FreeBSD&nbsp;的,&nbsp;但仍然会套用到其它的&nbsp;Unix&nbsp;OSes&nbsp;上面。&nbsp;<BR>&nbsp;&nbsp;(特别是&nbsp;OpenBSD&nbsp;和&nbsp;NetBSD)&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;o&nbsp;这份&nbsp;HOW-TO&nbsp;还有其它语言的版本吗&nbsp;?&nbsp;<BR>&nbsp;&nbsp;就我所知,&nbsp;有俄语版:&nbsp;<BR>&nbsp;&nbsp;<A HREF="http://www.etrust.ru/osa/security.html">http://www.etrust.ru/osa/security.html</A>&nbsp;<BR>&nbsp;&nbsp;和中文版:&nbsp;<BR>&nbsp;&nbsp;<A HREF="http://water.ite.ntnu.edu.tw/doc/cfbhow2.txt">http://water.ite.ntnu.edu.tw/doc/cfbhow2.txt</A>&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;o&nbsp;TODO:&nbsp;<BR>&nbsp;&nbsp;将包含&nbsp;/etc/login.conf&nbsp;和&nbsp;login&nbsp;classes&nbsp;<BR>&nbsp;&nbsp;将提及使用&nbsp;X&nbsp;的场合&nbsp;<BR>&nbsp;&nbsp;将会有&nbsp;html&nbsp;版&nbsp;<BR>&nbsp;<BR>o&nbsp;网路&nbsp;<BR>&nbsp;&nbsp;o&nbsp;inetd&nbsp;(Inet&nbsp;Daemon)&nbsp;<BR>&nbsp;&nbsp;网路在系统安全上扮演了一个很重要的角色。FreeBSD&nbsp;的根基是有着内建网路功能,&nbsp;且&nbsp;<BR>&nbsp;&nbsp;具有最稳最快的&nbsp;TCP/IP&nbsp;stacks&nbsp;的&nbsp;4.4BSD。这个&nbsp;stack&nbsp;支援了非常多的协定像是&nbsp;<BR>&nbsp;&nbsp;telnet,&nbsp;ftp,&nbsp;talk,&nbsp;rsh&nbsp;等...&nbsp;这些&nbsp;service&nbsp;的的主设定档便是&nbsp;/etc/inetd.conf。&nbsp;<BR>&nbsp;&nbsp;要编辑这个档,&nbsp;请输入&nbsp;&quot;vi&nbsp;/etc/inetd.conf&quot;&nbsp;(在这个例子里,&nbsp;我使用&nbsp;vi&nbsp;。你可以&nbsp;<BR>&nbsp;&nbsp;使用其它你较为上手的编辑器。或许你可以试试&nbsp;pico)。如果你要使用&nbsp;pico,&nbsp;请在启&nbsp;<BR>&nbsp;&nbsp;动它时加上&nbsp;-w&nbsp;选项:&nbsp;&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;-w&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;关掉自动断行。(因此可以容许超过&nbsp;80&nbsp;字元的行存在)&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;这选项在编辑&nbsp;/etc/inetd.conf&nbsp;时非常有用。&nbsp;<BR>&nbsp;&nbsp;当然了,&nbsp;你也可以使用&nbsp;ee&nbsp;-&nbsp;它随着&nbsp;FreeBSD&nbsp;一起&nbsp;&quot;出厂&quot;&nbsp;的,&nbsp;而且也是&nbsp;root&nbsp;预设&nbsp;<BR>&nbsp;&nbsp;的编辑器。不过,&nbsp;请再&nbsp;&quot;echo&nbsp;$EDITOR&quot;&nbsp;&nbsp;确认一次。&nbsp;&nbsp;开启了这个档案後,&nbsp;你可以看&nbsp;<BR>&nbsp;&nbsp;到里面怎麽描述每个&nbsp;service&nbsp;怎麽启动,&nbsp;要以那位使用者执行等等的资讯。(man&nbsp;5&nbsp;<BR>&nbsp;&nbsp;inetd.conf)既然这个档案是许多&nbsp;internet&nbsp;service&nbsp;的主要设定档,&nbsp;好好的设定它便&nbsp;<BR>&nbsp;&nbsp;是一件十分重要的事。你要关掉一个&nbsp;service的话,只消在那一行前面加个&nbsp;&quot;#&quot;&nbsp;符号。&nbsp;<BR>&nbsp;&nbsp;基本的概念是,&nbsp;关掉些你不熟悉的&nbsp;services&nbsp;-&nbsp;如果你不知道那个&nbsp;service&nbsp;是啥,&nbsp;或&nbsp;<BR>&nbsp;&nbsp;者不知道它可以干啥。理想状态下,&nbsp;你不须要把所有的&nbsp;service&nbsp;都打开。例如,&nbsp;你的&nbsp;<BR>&nbsp;&nbsp;器只是要跑&nbsp;web&nbsp;server。这种情况下,&nbsp;你只要启动&nbsp;ssh&nbsp;和&nbsp;httpd&nbsp;便够了。关於啥是&nbsp;<BR>&nbsp;&nbsp;ssh,&nbsp;下面会说明。如果你啥&nbsp;service&nbsp;都不想跑,&nbsp;最直接乾脆的方法是-关掉&nbsp;inetd。&nbsp;<BR>&nbsp;&nbsp;做法很简单,&nbsp;只要编辑&nbsp;/etc/rc.conf&nbsp;并且把&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;inetd_enable=&quot;YES&quot;&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;改成&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;inetd_enable=&quot;NO&quot;&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;就可以了。&nbsp;<BR>&nbsp;&nbsp;如此一来没人可以&nbsp;telnet,&nbsp;rlogin,&nbsp;或&nbsp;ftp&nbsp;到你的电脑。&nbsp;<BR>&nbsp;&nbsp;如果你决定要启动你的&nbsp;inetd&nbsp;的话,&nbsp;记得启动&nbsp;log&nbsp;选项,&nbsp;并提高一个&nbsp;service&nbsp;每分&nbsp;<BR>&nbsp;&nbsp;钟启动的上限数目。(预设值是&nbsp;256,&nbsp;我建议提高到&nbsp;1024-自行叁照下面解说调整吧!)&nbsp;<BR>&nbsp;&nbsp;为什麽要这麽做呢...?&nbsp;就&nbsp;modem&nbsp;user&nbsp;或是低速专线用户是没什麽差别。但高速线路&nbsp;<BR>&nbsp;&nbsp;的人,&nbsp;上限值太低会蹦出一个&nbsp;DoS&nbsp;attack(Denial&nbsp;of&nbsp;Service)。某个坏心的人可以简&nbsp;<BR>&nbsp;&nbsp;单的用一个&nbsp;shell&nbsp;script&nbsp;同时搞出超过&nbsp;256&nbsp;个&nbsp;connections,&nbsp;这麽一来你的&nbsp;inetd&nbsp;<BR>&nbsp;&nbsp;会很不幸的阵亡。换句话说,&nbsp;如果你想让每分钟每个&nbsp;service&nbsp;可接受的connection&nbsp;数&nbsp;<BR>&nbsp;&nbsp;多点,&nbsp;记得做如下的设定,&nbsp;不然来个坏心的人就可以搞垮你的电脑。因此,&nbsp;在这行&nbsp;<BR>&nbsp;<BR>inetd_enable=&quot;YES&quot;&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;下面的&nbsp;<BR>&nbsp;<BR>inetd_flags=&quot;&quot;&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;&nbsp;要改成:&nbsp;<BR>&nbsp;<BR>inetd_flags=&quot;-l&nbsp;-R&nbsp;1024&quot;&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;这会将连线的动作都&nbsp;log&nbsp;下来(-l&nbsp;叁数)而且将同时最大连线数从预设的&nbsp;256&nbsp;增加到&nbsp;<BR>&nbsp;&nbsp;1024。你还须要对你的&nbsp;/etc/syslog.conf&nbsp;作些修改,&nbsp;这些等会儿会提到。&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;o&nbsp;SSH&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;在以下提到的案例中,&nbsp;你完全不须要&nbsp;run&nbsp;inetd。例如,&nbsp;如果你只有跑&nbsp;web,&nbsp;news,&nbsp;或&nbsp;<BR>&nbsp;&nbsp;是&nbsp;nfs&nbsp;server,&nbsp;那麽就没有必要在你的机器上再跑其它的services。但是你一定会问,&nbsp;<BR>&nbsp;&nbsp;&quot;我要怎麽控制我的机器啊!?&quot;&nbsp;嗯嗯,&nbsp;所以现在要介绍&nbsp;SSH。你可以透过&nbsp;SSH&nbsp;(Secure&nbsp;<BR>&nbsp;&nbsp;Shell)&nbsp;来登入你的机器。Secure&nbsp;Shell&nbsp;当初便是设计来取代&nbsp;rsh,&nbsp;rlogin&nbsp;等其它的&nbsp;<BR>&nbsp;&nbsp;Berkeley&nbsp;r*&nbsp;命令。相信你很快就会了解&nbsp;SSH&nbsp;是如何有用,而且开始使用它,来代替其&nbsp;<BR>&nbsp;&nbsp;它的程式像是&nbsp;telnet&nbsp;和&nbsp;ftp。SSH&nbsp;具有很多功能，但是最为人知的是,&nbsp;它的加密通讯&nbsp;<BR>&nbsp;&nbsp;方式,&nbsp;也就是防止你的密码和资料以明码的方式在网路上传输。如果你使用&nbsp;telnet,你&nbsp;<BR>&nbsp;&nbsp;的通讯内容可能会被&quot;窃听&quot;:&nbsp;传输中的资料被改变,&nbsp;通讯内容被看到。(不是有&nbsp;S/Key&nbsp;<BR>&nbsp;&nbsp;可以解决吗?&nbsp;很不幸的,&nbsp;它还是有着插入资料和连接时被破解的问题)&nbsp;我希望你可以完&nbsp;<BR>&nbsp;&nbsp;全的关掉&nbsp;inetd&nbsp;而使用&nbsp;SSH。如果你认为完全不靠&nbsp;inetd&nbsp;来启动某些&nbsp;services,是完&nbsp;<BR>&nbsp;&nbsp;完全全不可能的事,&nbsp;那麽希望你至少启动&nbsp;log&nbsp;功能,&nbsp;而且要增加每分钟同一个&nbsp;servi-&nbsp;<BR>&nbsp;&nbsp;ce&nbsp;可启动的次数。&nbsp;(原因上面有提到)&nbsp;<BR>&nbsp;&nbsp;你可以从&nbsp;<A HREF="ftp://ftp.funet.fi/pub/unix/security/login/ssh">ftp://ftp.funet.fi/pub/unix/security/login/ssh</A>&nbsp;下载&nbsp;SSH。&nbsp;<BR>&nbsp;&nbsp;若你想要更简单的方法:&nbsp;<BR>&nbsp;<BR>#&nbsp;cd&nbsp;/usr/ports/security/ssh&nbsp;<BR>#&nbsp;make&nbsp;install&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;如果你有不是使用&nbsp;Unix&nbsp;的使用者,&nbsp;那麽可以从下面的站台抓到&nbsp;win32&nbsp;SSH&nbsp;程式:&nbsp;<BR>&nbsp;&nbsp;<A HREF="http://fox.doc.ic.ac.uk/~ci2/ssh/">http://fox.doc.ic.ac.uk/~ci2/ssh/</A>&nbsp;<BR>&nbsp;&nbsp;<A HREF="http://www.zip.com.au/~roca/ttssh.html">http://www.zip.com.au/~roca/ttssh.html</A>&nbsp;<BR>&nbsp;&nbsp;<A HREF="http://bmrc.berkeley.edu/people/chaffee/winntutil.html">http://bmrc.berkeley.edu/people/chaffee/winntutil.html</A>&nbsp;<BR>&nbsp;&nbsp;<A HREF="http://public.srce.hr/~cigaly/ssh">http://public.srce.hr/~cigaly/ssh</A>&nbsp;<BR>&nbsp;&nbsp;SecureCRT&nbsp;from&nbsp;<A HREF="http://www.vandyke.com">http://www.vandyke.com</A>&nbsp;<BR>&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;o&nbsp;inetd&nbsp;(part&nbsp;II)&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;&nbsp;&nbsp;o&nbsp;telnetd&nbsp;<BR>&nbsp;<BR>&nbsp;&nbsp;好吧,&nbsp;你仍然执意要使用&nbsp;inetd。那麽我们来看看在&nbsp;inetd.conf&nbsp;有那些选项,&nbsp;可以增&nbsp;<BR>&nbsp;&nbsp;进你的系统安全。在攻击某系统之前,&nbsp;攻击者都会先收集该系统的相关资讯。就&nbsp;teln-&nbsp;<BR>&nbsp;&nbsp;etd&nbsp;而言,&nbsp;你可以试试在&nbsp;telnetd&nbsp;那行後面加个&nbsp;-h:&nbsp;<BR>&nbsp;<BR>telnet&nbsp;&nbsp;stream&nbsp;&nbsp;tcp&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;nowait&nbsp;&nbsp;root&nbsp;&nbsp;&nbsp;&nbsp;/usr/libexec/telnetd&nbsp;&nbsp;&nbsp;&nbsp;telnetd&nbsp;-h&nbsp;<BR>
12345

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -