johnkeeping / chpersroot

Personal+Personality Chroot

chpersroot: Personal+Personality Chroot

A program to simplify the use of 32-bit chroots on 64-bit non-multilib Linux systems.

Basically, this program is equivalent to running:

sudo linux32 chroot /path/to/my/chroot su -l "$USER" [args]

but because it's installed setuid you don't need to type a password and the command line is somewhat shorter because the location of the chroot is compiled in at build time.

Build Instructions

Setup your configuration if you want to:

cat >config.mak <<\EOF
prefix=/usr/local
EOF

then build:

make && sudo make install

Configuration

The configuration file /etc/chpersroot.conf is read to determine how to enter a chroot. This file is in INI format, although certain keys can be multi-valued.

An example file might be:

[gentoo32]
    rootdir = /gentoo32
    copyfile = /etc/resolv.conf
    personality = linux32

The configuration to use is chosen by the basename of argument zero, in other words it is the filename by which the program is invoked. If you only have a single configuration and don't want to worry about this, just call the configuration chpersroot, otherwise you should create a symbolic link somewhere in your path that links from your configuration's name to the chpersroot executable.

Configuration Keys

The following configuration keys are available:

rootdir

The path to the new root.

copyfile

A file to be copied into the new root. This key may be specified multiple times if you want to copy multiple files.

personality

The personality for the chroot. This is one of the PER_ variables from /usr/include/linux/personality.h with the prefix removed and underscores converted to hyphens; the comparison is case insensitive.