etc/agfw/autoproxy-gfwlist/validateChecksum.pl

   1 #!/usr/bin/perl
   2
   3 #############################################################################
   4 # This is a reference script to validate the checksum in downloadable       #
   5 # subscription. This performs the same validation as Adblock Plus when it   #
   6 # downloads the subscription.                                               #
   7 #                                                                           #
   8 # To validate a subscription file, run the script like this:                #
   9 #                                                                           #
  10 #   perl validateChecksum.pl subscription.txt                               #
  11 #                                                                           #
  12 # Note: your subscription file should be saved in UTF-8 encoding, otherwise #
  13 # the validation result might be incorrect.                                 #
  14 #                                                                           #
  15 # 20100418: Stolen from ABP with minor modification for AutoProxy project   #
  16 #############################################################################
  17
  18 use strict;
  19 use warnings;
  20 use Digest::MD5 qw(md5_base64);
  21
  22 die "Usage: $^X $0 subscription.txt\n" unless @ARGV;
  23
  24 my $file = $ARGV[0];
  25 my $data = readFile($file);
  26
  27 # Normalize data
  28 $data =~ s/\r//g;
  29 $data =~ s/\n+/\n/g;
  30
  31 # Extract checksum
  32
  33 # Remove checksum
  34 $data =~ s/^\s*!\s*checksum[\s\-:]+([\w\+\/=]+).*\n//mi;
  35 my $checksum = $1;
  36 die "Error: couldn't find a checksum in the file\n" unless $checksum;
  37
  38 # Calculate new checksum
  39 my $checksumExpected = md5_base64($data);
  40
  41 # Compare checksums
  42 die "Error: invalid checksum\n" unless $checksum eq $checksumExpected;
  43
  44 sub readFile
  45 {
  46   my $file = shift;
  47
  48   open(local *FILE, "<", $file) || die "Error: could not read file '$file'";
  49   binmode(FILE);
  50   local $/;
  51   my $result = <FILE>;
  52   close(FILE);
  53
  54   return $result;
  55 }