git.distorted.org.uk Git - u/mdw/catacomb/blob - pcheck.pl

   1 #! /usr/bin/perl
   2
   3 # Reads ptab.in or similarly-formatted file; writes a calc script to check
   4 # it.
   5
   6 while (<>) {
   7   next if /^\s*(\#[^!]|$)/;
   8   @F = split;
   9   if ($F[0] eq "group") {
  10     $group = $F[1];
  11     $_ = <>; @F = split; $F[0] eq "p" or die $F[0]; $p = $F[1];
  12     $_ = <>; @F = split; $F[0] eq "q" or die $F[0]; $q = $F[1];
  13     $_ = <>; @F = split; $F[0] eq "g" or die $F[0]; $g = $F[1];
  14     print <<EOF;
  15       print "testing $group...";
  16       p = $p;
  17       q = $q;
  18       g = $g;
  19       if (!ptest(p)) print "  p not prime";
  20       if (!ptest(q)) print "  q not prime";
  21       if ((p - 1)%q) print "  q doesn't divide p - 1";
  22       h = (p - 1)/q;
  23       if (pmod(g, q, p) != 1) print "  g doesn't have order q";
  24       if (pmod(g, h, p) == 1) print "  g generates overly large group";
  25       ff = 2;
  26 EOF
  27     $ll = 0;
  28     for (;;) {
  29       $_ = <>; @F = split; $F[0] eq "#:factor" or last; $f = $F[1];
  30       print <<EOF;
  31         f = $f;
  32         if (!ptest(f)) print "  factor not prime", f;
  33         ff *= f;
  34 EOF
  35       $ll = 1;
  36     }
  37     if ($ll) {
  38       print <<EOF;
  39         if (ff != p - 1) print "  missing factors";
  40 EOF
  41     }
  42   }
  43 }