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bcrypt

NAME

bcrypt - A cross platform blowfish file encryption utility.

SYNOPSIS

bcrypt -[orc][-sN] file1 file2 ...

DESCRIPTION

bcrypt is a cross platform file encryption utility. Encrypted files are portable across all supported operating systems and processors.

Encrypted files will be saved with a .bfe extension. Any files ending in .bfe will be assumed to be encrypted with bcrypt and it will attempt to decrypt them. Any other input files will be encrypted. If more than one type of file is given, bcrypt will process all files which are the same as the first filetype given.

By default, bcrypt will compress input files before encryption, remove input files after they are processed (assuming they are processed successfully) and overwrite input files with random data to prevent data recovery.

Passphrases can be between 8 and 56 characters. Regardless of the passphrase size, the key is hashed internally to 448 bits - the largest keysize supported by the blowfish algorithm. However, it is still wise to use a strong passphrase.

bcrypt uses the blowfish encryption algorithm published by Bruce Schneier in 1993. More information on the algorithm can be found at: http://www.counterpane.com/blowfish.html

Specifically, bcrypt uses Paul Kocher's implementation of the algorithm. The source distributed with bcrypt has been slightly altered from the original. Original source code can be obtained from: http://www.counterpane.com/bfsh-koc.zip

OPTIONS

The options o,c and r each have the opposite effects if the appropriate settings are altered from the default in config.h. To determine what effect each of these have, run bcrypt without any options.

Encrypted files should be compatible between most systems. Binary compatibility has been tested for all systems listed in the supported platforms section.

-o

print output to standard out. Implies -r

-c

Do NOT compress files before encryption.

-r

Do NOT remove input files after processing

-sN

How many times to overwrite input files with random data before processing. The default number of overwrites is 3. Use -s0 to disable this feature. No effect if -r is supplied.

AUTHORS

Bcrypt was written by Johnny Shelley and uses the blowfish encryption algorithm published by Bruce Schneier, specifically it uses Paul Kocher's implementation of the algorithm. The native Win32 support is by Philip Stolarzyk. This manpage was written by Eskild Hustvedt <eskild@mandriva.org>

SUPPORTED PLATFORMS

No operating systems other than those listed here hav been tested, but most should work with minimal modifications. If you get bcrypt to compile without errors on any other platform or architecture, I'd like to know it. If patches are necessary to get bcrypt to work on your OS or architecture I will try to incorporate them into the main distribution. If you have a machine is not listed below that is incapable of compiling bcrypt and are willing to give me access to the machine, I will make an attempt to port it to your OS.

Bcrypt has been successfully tested on the following platforms:

x86:

FreeBSD, OpenBSD, Linux, Cygwin, Win32

Sparc R220:

Solaris 2.7, 2.8

Sparc Ultra60:

Linux 2.4

Alpha:

Linux 2.4

PPC G4:

MacOS X 10.1 SERVER

PPC RS/6000:

Linux 2.4

MIPS:

Linux 2.0.34 (Cobalt)

HPPA 1.1

HP-UX 11.0

VERSION

Written for bcrypt version 1.1. This is version 0.1.1 of the manpage.

LICENSE

 Copyright (c) 2002 Johnny Shelley <jshelley@cahaus.com>
 All rights reserved.

 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions
 are met:

 1. Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.

 2. Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in
    the documentation and/or other materials provided with the
    distribution.

3. Neither the name of the author nor any contributors may be used
   to endorse or promote products derived from this software without
   specific prior written permission.

THIS SOFTWARE IS PROVIDED BY COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.