Shell in a box
Shell in a Box allows you to control a computer over the network using a Linux console in a web page. This article shows how to set it up with SUSE Linux 12.1. It should work same or similar with every distribution.
Get it
- open a console as root.
- Download shell in a box from google
wget http://shellinabox.googlecode.com/files/shellinabox-2.11.tar.gz
- unpack it
tar xvzf shellinabox-2.11.tar.gz
- install some dependencies, in this example for SUSE Linux 12.1:
yast -i make
- build it
cd shellinabox-2.11 ./configure && make && make install
- make sure the firewall is open, here is an example for SUSE Linux:
rcSuSEfirewall2 stop
- add a user for shell in a box, in this example user
useradd -m user passwd user
- call shell in a box
cd /tmp shellinaboxd &
- test it by surfing to your computer: http://localhost:4200
- now set up apache for https so your passwords are not transmitted unencrypted over the internet
Make it persistant
You want the shell in a box daemon shellinaboxd to be started when booting your machine, so
- add the following line to /etc/init.d/boot.local:
shellinaboxd &
- configure the firewall to always open up port 80 or stop it persistantly:
chkconfig SuSEfirewall2_setup off chkconfig SuSEfirewall2_init off
- configure apache to start on boot
chkconfig apache2 on
Co-exist with a web server
You probably want shell in a box to be reachable via port 80 (so you can use it from within a typical corporate network) and you may want to run a web server on the same machine. So here is how you integrate shell in a box into an Apache2 web server
- install apache2, in this example for SUSE Linux 12.1:
yast -i apache2
- enable a reverse proxy. To do this, edit /etc/sysconfig/apache2 and add the following words to APACHE_MODULES: proxy proxy_http. In the end your line may read like this:
APACHE_MODULES="actions alias auth_basic proxy proxy_http authn_file authz_host authz_groupfile authz_default authz_user autoindex cgi dir env expires include log_config mime negotiation setenvif ssl userdir php5"
- tell apache that if someone calls http://yourserver.yourdomain/shell this is forwarded to http://yourserver.yourdomain:4200 internally. To do this, edit /etc/apache2/default-server.conf, add a block
<IfModule mod_proxy.c> <Location /shell> ProxyPass http://127.0.0.1:4200 </Location> </IfModule>
TroubleShooting
Symptom: ShellInABoxD does not start, it tells the error message:
Cannot read valid certificate from "certificate.pem". Check file permissions and file format.
Reason: See http://code.google.com/p/shellinabox/issues/detail?id=59. ShellInABoxD tries to create a file certificate.pem in the folder where it is started as user nobody:
/tmp # ll certificate.pem -rw------- 1 nobody nogroup 2794 Aug 5 07:53 certificate.pem
Solution: Start shellinaboxd in a directory that every user can access, e.g. /tmp:
cd /tmp shellinaboxd &