Pastebin

#!/usr/bin/perl -W

use strict;

sub usage {
  print "$0 <cert file.html> <output.p12>"
}

$#ARGV == 1 or usage;

open HTML, $ARGV[0];
while (<HTML>) {
    if (/^pkcs12="(.*)";/) {
        $_ = $1;
        s/(.{64})/$1\n/g;
        open OPENSSL, "| openssl base64 -d -out $ARGV[1]";
        print OPENSSL $_;
        close OPENSSL;
    }
}
close HTML;