ref: 10274876313f8dabe8a8db8a94073d15b68f1807
dir: /changeblog/1596011563.ht/
<article> <header> <h2>Restrict RCPU User Access to Groups</h2> <b>Wed, 29 Jul 2020 10:32:43 +0200</b> </header> <p style="margin-top: 0; margin-bottom: 0.50in"></p> <p style="margin-top: 0; margin-bottom: 0.21in"></p> <p style="line-height: 1.4em; margin-left: 1.00in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: center;"> <span style="font-size: 12pt"><b>Restrict RCPU User Access to Groups</b></span></p> <p style="margin-top: 0; margin-bottom: 0.21in"></p> <p style="margin-top: 0; margin-bottom: 0.21in"></p> <p style="margin-top: 0; margin-bottom: 0.42in"></p> <p style="margin-top: 0; margin-bottom: 0.21in"></p> <p style="margin-top: 0; margin-bottom: 0.05in"></p> <p style="margin-top: 0; margin-bottom: 0.50in"></p> <p style="line-height: 1.2em; margin-left: 1.00in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt">This is how to restrict user access to groups. You can use this to enable </span><span style="font-size: 10pt"><tt>rcpu</tt></span><span style="font-size: 10pt"> access for all users of a specific group. All other groups will not be allowed. </span></p><p style="margin-top: 0; margin-bottom: 0.05in"></p> <p style="line-height: 1.2em; margin-left: 1.00in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt">To allow access only to </span><span style="font-size: 10pt"><tt>sys</tt></span><span style="font-size: 10pt"> group members: adjust your </span><span style="font-size: 10pt"><tt>/rc/bin/service/tcp17019</tt></span><span style="font-size: 10pt"> </span></p><p style="margin-top: 0; margin-bottom: 0.05in"></p> <p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt>#!/bin/rc </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt>userfile=/adm/users </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt>fn useringroup{ </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> grep $1 $userfile | { </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> found=0 </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> while(~ $found 0 && line=‘:{read}){ </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> if(~ $line(2) $2){ </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> found=1 </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> } </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> } </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> if(~ $found 1) </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> status=’’ </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> if not </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> status=’not found’ </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> } </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt>} </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt>if(~ $#* 3){ </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> netdir=$3 </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> remote=$2!‘{cat $3/remote} </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt>} </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt>fn server { </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> ~ $#remote 0 || echo -n $netdir $remote >/proc/$pid/args </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> rm -f /env/’fn#server’ </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt> . <{n=‘{read} && ! ~ $#n 0 && read -c $n} >[2=1] </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt>} </tt></span></p><p style="line-height: 1.2em; margin-left: 1.35in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt"><tt>exec tlssrv -a /bin/rc -c ’useringroup $user sys && server’ </tt></span></p><p style="margin-top: 0; margin-bottom: 0.05in"></p> <p style="line-height: 1.2em; margin-left: 1.00in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt">This checks if the user is in group </span><span style="font-size: 10pt"><tt>sys</tt></span><span style="font-size: 10pt"> and only then calls the </span><span style="font-size: 10pt"><tt>server</tt></span><span style="font-size: 10pt"> function. Otherwise the connection is terminated. </span></p><p style="margin-top: 0; margin-bottom: 0.05in"></p> <p style="line-height: 1.2em; margin-left: 1.00in; text-indent: 0.00in; margin-right: 1.00in; margin-top: 0; margin-bottom: 0; text-align: justify;"> <span style="font-size: 10pt">This is especially useful if you want a CPU server to expose filesystems </span><span style="font-size: 10pt"><i>and</i></span><span style="font-size: 10pt"> have cpu access for administrators only. </span></p><p style="margin-top: 0; margin-bottom: 0.50in"></p> </article>