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--------------------
| 1. abstract      |
| 2. dependecies   |
| 3. parts         |
| 4. functionality |
--------------------

1. abstract
-----------
impauth is a collection of tools that provide improved
authentication facilities using data stored on an usbstick.
You can store your username and pass and will be logged in
automatically. Also encrypted devices will be opened for you.
If you want, you can store your complete homedir on the
stick and log in on every pc that allows this.
impauth also provides a set of configuration-tools.

2. dependencies
---------------
impauth's basic layer is only udev-based. Of course,
you need ext2fs, too.
If you want to use the encryption facilities, you have to
have enabled dm_crypt, the aes cipher and loop device support 
in the kernel and you need the cryptsetup program.

3. parts
--------
-the files /etc/udev/rules.d/_impauth.rules and 
 /etc/hotplug.d/usbstick/_impauth.dev
	These are files for udev that map usbsticks to
	/dev/usbstick, create symlinks to internal names
	(such s /dev/sg0...) and do all necessary things if a 
	stick that is suited for impauth is detected.

-the programs timpauth,nimpauth,qimpauth,kimpauth and eimpauth
	These are config tools for impauth. All configuration is
	done through this. DON'T EDIT THE STICK ITSELF! These
	programs can also be used to access a encrypted homedir
	on the stick.
	The names indicate the interface:
		-timpauth is text-only
		-nimpauth uses ncurses
		-gimpauth  "   gtkmm
		-qimpauth  "   qt
		-eimpauth  "   the efl

-patches for xdm, gdm, kdm, entrance and agetty

4. functionality
----------------
there are two ways to use impauth (or, more correct, an usbstick
edited by one of the ?impauth tools), in local mode or in stand-
alone mode.

-local mode
 You can use this stick unly at the pc it was configured
 (ore on a more or less exactly same configured system).
 
 facilities
	automatic login
	  You can store your username and pass on the stick and
	  become logged in if you insert the stick
	
	storing configs in an encrypted file (because of passwords
	saved there)
	  all ~/.* are saved at a encrypted file at ~, symlinks
	  are created if the stick is inserted
	  problem: this is only useful if done before logging in
	  because otherwise the "local" config will be overridden

	open encrypted devices
	  impauth can save the passwords and automatically open
	  encrypted devices/files

-stand-alone mode
 You can use the stick on every pc that has impauth and allows
 this feature, your complete home is stored on the stick

 facilities
	additional to those you have in local mode, you can save
	your complete home  on the stick. In this case, it's not
	reasonable to work with encrypted devices. But you can save
	the home encrypted, without saving the pass on the stick. This
	has the following advantage: you can type your pass into a
	patched dm's entry after inserting the stick. This pass is used
	to decrypt the home directory on the stick. If this succeeds,
	you get authenticated, else not.