http://www.jmcresearch.com/projects/jail/
Jail Chroot Project is an attempt of write a tool that builds a chrooted environment. The main goal of Jail is to be as simple as possible, and highly portable. The most difficult step when building a chrooted environment is to set up the right libraries and files. Here, Jail comes to the rescue with a tool to automagically configures & builds all the required files, directories and libraries. Jail is licensed under the GNU General Public License.
Jail program has been written using C, and the setup script has been written using a bash script and perl. Jail has been tested under Linux (Debian 2.1 & 2.2, RedHat 6.1, 6.2 and 7.0 and Caldera Openlinux 7.0), Solaris (2.6), IRIX (6.5) and FreeBSD 4.3. Some people has contributed to jail with patches and ideas. Thanks to all of them.
Jail supports lots of interesting features:
Runs on Linux, Solaris, IRIX and freeBSD (tested) and should run in any of the flavours of these operating systems.
Modular design, so you can port Jail in an easy way.
Support for multiple users in a single chrooted environment.
Fully customizable user shell.
Support for multiple servers: telnetd, sshd, ftpd...
Easy to install thanks to the enviroment creation script.
Should work in any UNIX.
Ease of porting.
Allows run any kind of program as a shell.
