TTHSUM

Section: GNU/Linux (1)
Updated: 12th June 2004
Index
Return to Main Contents
 

NAME

tthsum - generates or checks TTH message digests

 

SYNOPSIS

tthsum [-bv] [-c [file]] | [file...]

 

DESCRIPTION

tthsum generates or checks TTH checksums (root of the THEX hash tree). The Merkle Hash Tree, invented by Ralph Merkle, is a hash construct that exhibits desirable properties for verifying the integrity of files and file subranges in an incremental or out-of-order fashion. tthsum uses the Tiger hash algorithm for both the internal and the leaf nodes.

The specification of the THEX algorithm is at:
 .  http://www.open-content.net/specs/draft-jchapweske-thex-02.html

The specification of the Tiger hash algorithm is at:
 .  http://www.cs.technion.ac.il/~biham/Reports/Tiger/

Normally tthsum generates checksums of all files given to it as a parameter and prints the checksums followed by the filenames. If, however, -c is specified, only one filename parameter is allowed. This file should contain checksums and filenames to which these checksums refer, and the files listed in that file are checked against the checksums listed there. See option -c for more information.

 

OPTIONS

-b
An md5sum compatibility option. Te only thing -b does is print an asterisk preceding the filename in the output. (It does not specify binary mode on WIN32. Binary mode is used regardless.)

-c
Check tthsum of all files listed in file against the checksum listed in the same file. The actual format of that file is the same as output of tthsum. That is, each line in the file describes a file. A line looks like:

<TTH checksum>  <filename>

So, for example, if a file were created and its message digest calculated like so:

echo foo > tth-test-file; tthsum tth-test-file

tthsum would report:

A2MPPCGS5CPJV6AOAP37ICDCFV3WYU7PBREC6FY  tth-test-file

-v
Be more verbose. Print filenames when checking (with -c).

 

NOTES

tthsum intentionally uses an interface identical to md5sum.

tthsum uses BASE32 encoding consisting of the following characters: ABCDEFGHIJKLMNOPQRSTUVWXYZ234567.

tthsum does not accept long options such as --help.

The hashing code, copied from DC++, has been a lot more work than this simple program.

 

SEE ALSO

md5sum(1)

 

AUTHOR

tthsum and this manpage were written by Walter Doekes (walter@djcvt.net). The hashing code is copied directly from DC++, an open source peer-to-peer file sharing program by Jacek Sieka (jacek@creatio.se) who had based the hashing code on the one used in BCDC++ (a modified DC++) by Dustin Brody (blackclaw@parsoma.net). The md5sum manpage, written by Juho Vuori (javuori@cc.helsinki.fi), was used as a template. This manpage was proofread by Dustin Brody.


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
NOTES
SEE ALSO
AUTHOR

This document was created by man2html, using the manual pages.
Time: 14:53:14 GMT, June 12, 2004