Original version which started the trend
9 March 1995 The original version which
started this trend of perl crypto hacks.
An explanation of how this one works was
posted to the cypherpunks list by Hal Finney shortly after I posted it.
#!/usr/local/bin/perl -- export-a-crypto-system sig, RSA in 5 lines of PERL:
($s,$k,$n)=@ARGV;$w=length$n;$k="0$k"if length($k)&1;$n="0$n",$w++if$w&1;die
"$0 -d|-e key mod out\n"if$s!~/^-[de]$/||$#ARGV<2;$v=$w;$s=~/d/?$v-=2:
$w-=2;$_=unpack('B*',pack('H*',$k));s/^0*//g;s/0/d*ln%/g;s/1/d*ln%lm*ln%/g;
$c="1${_}p";while(read(STDIN,$m,$w/2)){$m=unpack("H$w",$m);chop($a=
`echo 16o16i\U$m\Esm\U$n\Esn$c|dc`);print pack('H*','0'x($v-length$a).$a);}
Pure perl version
Pure perl version by Clifford Adams in 5
lines of perl.
#!/usr/local/bin/perl -s
do 'bigint.pl';($_,$n)=@ARGV;s/^.(..)*$/0$&/;($k=unpack('B*',pack('H*',$_)))=~
s/^0*//;$x=0;$z=$n=~s/./$x=&badd(&bmul($x,16),hex$&)/ge;while(read(STDIN,$_,$w
=((2*$d-1+$z)&~1)/2)){$r=1;$_=substr($_."\0"x$w,$c=0,$w);s/.|\n/$c=&badd(&bmul
($c,256),ord$&)/ge;$_=$k;s/./$r=&bmod(&bmul($r,$r),$x),$&?$r=&bmod(&bmul($r,$c
),$x):0,""/ge;($r,$t)=&bdiv($r,256),$_=pack(C,$t).$_ while$w--+1-2*$d;print}
Comments, html bugs to me
(Adam Back) at
<adam@cypherspace.org>