UK shirt design

This page probably won't be very interesting to you unless you want to print shirts yourself, or are curious to print the postscript files which make up the design.

File formats

These files are links to actual gzipped postscript files, you will need gzip (GNU zip, available for PCs here GNU zip), which is basically standard on unix these days. To save these links to file you will need to tell your browser to save the next item, with netscape this is hold down the shift key and click on the URL of the file you want. For those with slow dowload rate, I have indicated size in brackets after file name. You should save the files as ending in .gz even if your browser has other ideas, or you will have to rename them afterwards because gzip insists on them ending in .gz. Then you type gzip -d file.gz and it will create These files are straight postscript files, and should print on any standard postscript printer.

Front of shirt

File warning.gz(79k) says:

This shirt is classified as a munition and
may not be exported from the United
States, or shown to a foreign national
File rsa.gz(36k) says:
encryption in perl

Machine readable version of program: CODE128 barcode

The blank lines between 'encryption in perl' and 'Machine readable...' is a gap left for the next file, the perl program in OCRA. You just get your printer to montage them together.

File perl.gz(5k) says, in an OCRA font:

#!/bin/perl -s-- -export-a-crypto-system-sig -RSA-3-lines-PERL $m=unpack(H.$w,$m."\0"x$w),$_=`echo "16do$w 2+4Oi0$d*-^1[d2%Sa 2/d0<X+d*La1=z\U$n%0]SX$k"[$m*]\EszlXx++p|dc`,s/^.|\W//g,print pack('H*',$_)while read(STDIN,$m,($w=2*$d-1+length($n)&~1)/2)

File barcode.gz(104k) is a barcode of the above program, only it is in inverse video to prepare for being in a white box on a black shirt (it was a very painful experience inverting it, involved editing the raw postscript file, and playing with xfig output). If you're doing a black shirt, and want the barcode in a white box, use this file, if you're doing a white shirt (they've all been black so far), you'll need to use the second barcode, below.

File barcode2.gz(104k) is the same barcode again, without the colour inversion.

As you will note the barcode has 8 lines rather than 4 as in the program, this is to try to improve the chances of the shirt barcode being readable, Don Henson who was the first to ship shirts in the US, had someone try to scan the finished shirt with a barcode scanner: it failed! That was the motivation for the big clunky barcode files above. It might be ugly, but I have had confirmation from people who have bought shirts that it scans.

Because it is eight lines, when (and if) it scans it will come out like this:

#!/bin/perl -s $m=unpack( H.$w,$m."\0"x$w),$_=`echo "16do$w 2+4Oi0$d*-^1[d2% Sa2/d0<X+d*La1=z\U$n%0]SX $k"[$m*]\EszlXx++p|dc`,s/ ^.|\W//g,printpack('H*',$ _)while read(STDIN,$m,($w =2*$d-1+length($n)&~1)/2)

You will need to combine it all onto one long line, and add a line break between the '#!/bin/perl -s' and the '$m=unpack(H.$w ...' Then it should be functionally the same as the text on the shirt (the -export-a-crypto-system-sig -RSA-3-lines-PERL is just a comment). See this page for more detailed info on how to use perl-rsa.

Back of shirt

File ammend.gz(67k) is the US constitutional ammendments (it has the VOID stamp graphic below superimposed in red on top of, and partly obscuring it).

File void.gz(79k) the void stamp, basically just a big stamp with the word void in large stencil font diagonally in a box to resemble a big ammo crate like effect. Printed in red with puff effect (means raised effect, your printer should know what it means).

File itar.gz(79k) relevant sections from ITAR regulations, all in nice stencil font. It says (only it's all caps on the shirt because the stencil font has no lower case letters):

International Traffic in Arms Regulations

ITAR section 120.17 (4), verbatim:

Disclosing (including oral or visual disclosure) or transferring technical data to a foreign person, whether in the United States or abroad

ITAR section 121.1 (Category XIII)

lists tanks, heavy artillery, various other implements of mass destruction, and cryptographic software as export controlled defense articles

22 U.S.C 2778, 2779 says for violting ITAR

FINE of $1,000,000 and/or 10 years imprisonment per count

File france.gz(133k) is the French crypto regulations, plus perl RSA muntions T homepage URL. You'll want to edit the country, printer, and maybe URL if you have one. (I have gotten quite adept at editing postscript files, if it's a small change only you need). This says:

So, the technical data is THIS shirt, and that could be YOU

Crypto is illegal in France - penalty up to 500,000 FF
and/or 3months jail

Loi 90-1170 du 29/12/90 (art 28)

Do you have authorisation from SCSSI to wear this shirt?

Printed by Adam Back:

Made in the United Kingdom


The UK design was contributed to by a number of people: Josh Osborne for the idea of printing a muntions T-shirt from the perl .sig, the design was by TJ Hardin, who did the font and layout work, Mark Shoulson for helping me with TeX Metafont questions to get the OCRA font for the program text, Josh Osborne for providing software to make barcodes, and for some of the wording from the 1st muntions T-shirt which he got Joel Furr to print, Mike Norwick (EFF) for pointing out an error in the ITAR reference no, in the nick of time, and SaltRock surf gear for printing the shirts. Also there were many people who offered comments on earlier designs.
Comments, html bugs to me (Adam Back) at <>