Content-type: text/html Manpage of ppddsetup

ppddsetup

Section: User Commands (1)
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NAME

ppddsetup - setup, release or get details of a ppdd device  

SYNOPSIS

Used to control or display the connection between a ppdd device and a file or a disc partion.  

DESCRIPTION

The program ppddsetup is used to control the connection between a logical ppdd device and a real file or disc partition. The file or disc partition must have been initialised previously using ppddinit or ppdncrypt.  

Connecting

The connection is normally established by a simple command.  

ppddsetup -s ppdd_device file|disc_partition  

e.g. ppddsetup -s /dev/ppdd0 /dev/hda1
e.g. ppddsetup -s /dev/ppdd0 /home/allan/cryptfile  

The program will ask for a pass phrase. This may be either the master or working pass phrase. On succesful completion of the command the ppdd device can be used to access the decrypted data just as if it were a disc.  

There are other ways of connecting which all involve storing the pass phrase on disc. There are major security concerns about doing this. It makes sense only when the file containing the pass phrase is itself on a ppdd device. The usual scenario is that the root filesystem is encrytpted with ppdd and the pass phrases for the other filesystems are stored on the encrypted root. It is then necessary to enter just one pass phrase during the boot phase in order to access the root filesystem - the rest runs automatically. Do NOT use the following unless you know what you are doing.  

ppddsetup -a  

Use the information in /etc/ppddtab to setup everything defined in that file.  

ppddsetup -t device | file  

The device or file must be defined in /etc/ppddtab. The information which is not on the command line is taken from the entry in /etc/ppddtab - including the pass phrase.  

ppddsetup -p device | file passphrase-file  

Instead of using /etc/ppddtab this form of ppddinit use "passphrase-file"  

 

Displaying details

To display the details about a ppdd device:  

ppddsetup ppdd_device  

e.g. ppddsetup /dev/ppdd0  

 

Disconnecting

It is only possible to disconnect the ppdd device from the underlying host data file or device (disc partition) when there are no more users active on the device - i.e. no open inodes. If you have mounted the ppdd device you will need to umount it before the disconnect will work.  

ppddsetup -d ppdd_device  

e.g. ppddsetup -d /dev/ppdd0  

Checksums

The -c switch can be used in combination with the -d -p and -s switches.
In combination with -s or -p it checks the checksum. If no checksum is available or if the checksum is wrong the user is asked if he wants to accept this.
In combination with -d it generates a checksum, but only if the device was also setup with checksums enabled.
As checksum generation or checking involves reading all the data on the device it can take a long time. Progress messages are output during the process.  

OPTIONS

If any invalid combination of switches and arguments is used the program displays a primitive help message. The program takes not more than one switch and the argument(s) required depends on the switch.  

With a ppdd device as agrument and no switches ppddsetup displays the details of an existing connection between the device and a file or disc partition.  

-s     setup the connection
 

Takes the ppdd device and the real device or file as agruments. The real device must be a block device and would normally be a disc partition or a floppy disc. The file can reside on any type of filesystem. If it is on a read-only filesystem the ppdd device must later be mounted read-only. The file must already exist and must not be a sparse file. The host partition or file must have been initialised by ppddinit or ppdncrypt. A valid user entered pass phrase (master or working) is necessary before ppddsetup will enable the ppdd device.  

-d     release the connection
 

This requires the ppdd device as its single argument. The function will fail if there are any open inodes on the device. The most common failure is that the ppdd device is still mounted.  

-p     setup using a passphrase file
 

Very dangerous - use with care (or just for testing).  

-t     setup using /etc/ppddtab

-a     setup all devices defined in /etc/ppddtab
 

Slightly less dangerous - see ppddtab(7) for details.  

 

RETURN VALUE

The program returns 0 if everything worked as expected. That means that the ppdd device has been successfully connected to the host device or file.
The program returns 1 if anything has gone wrong.
 

ERRORS

All ppdd utilities display fairly meaningful errors (mostly on stderr). In all cases the errors have a unique error number to help locate the problem in the source code. If an error message is not clear then best source of explanation at this stage is the source itself.  

ENVIRONMENT

The program does not use any environment variables.  

FILES

Files (and devices) are specified as arguments.
 

SEE ALSO

ppdd(1) ppddcsum(1) ppdddown(1) ppddinit(1) ppddmchk(1) ppddpassw(1) ppdduprev(1) ppdecrypt(1) ppdncrypt(1) ppddtab(5).  

(c) 1999 Allan Latham - version 0.9

 

Index

NAME
SYNOPSIS
DESCRIPTION
Connecting
Displaying details
Disconnecting
Checksums
OPTIONS
RETURN VALUE
ERRORS
ENVIRONMENT
FILES
SEE ALSO
This document was created by man2html, using the manual pages.
Time: 16:36:54 GMT, September 14, 1999