NAME¶
bcrypt - blowfish file encryption
SYNOPSIS¶
bcrypt [
-orc][
-sN]
file ...
DESCRIPTION¶
bcrypt encrypts and decrypts files using the
blowfish algorithm.
Encrypted files will be saved with an extension of
.bfe. Any files ending
in
.bfe will be assumed to be encrypted with
bcrypt and 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 may 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.
OPTIONS¶
- -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 deleting.
The default number of overwrites is 3. Use -s0 to disable this feature. No
effect if -r is supplied.
NOTES¶
The
-o ,
-r ,and
-c options each have the opposite
effects if the appropriate settings are altered from the defaults in config.h.
To determine what effect each of these have on your system, run
bcrypt
without any options.
Encrypted files should be compatible between most systems. Binary compatibility
has been tested on all supported systems. There is a list of supported systems
in the README file that was included with this software.
BUGS¶
Probably. If you find that it will not compile and run on your system, or that
encrypted files are not compatible with other platforms, its probably because
I don't have access to the platform in question. Patches or access to an
unsupported machine are welcome.
AUTHOR¶
- johnny shelley
- <jshelley@cahaus.com>, <jshelley@ictransnet.com>
DISTRIBUTION¶
bcrypt includes Paul Kocher's implementation of the
blowfish
algorithm. The version distributed with
bcrypt has been altered.
Original sources are available from
http://www.counterpane.com/bfsh-koc.zip