#/usr/bin/perl -w
use MIME::Parser;

my $parser = new MIME::Parser;
$parser->decode_bodies(0);
$parser->decode_headers(0);
$parser->output_to_core(1);
$parser->tmp_to_core(1);

local($/) = undef;  # slurp

open(EMAIL, "63602021-5.eml");
binmode EMAIL;
$entity = $parser->parse_data(<EMAIL>);
close(EMAIL);

dump_entity($entity) if $entity;

sub dump_entity{
  my $ent = shift;
  my @parts = $ent->parts;
  if (@parts) {
    map { dump_entity($_) } @parts;
  } else {
    if(scalar($ent->head->mime_type) eq "application/pdf"){
      print "Part: "
            . $ent->head->recommended_filename
            . " (" . scalar($ent->head->mime_type) . ")\n";
      my $data_org = $ent->bodyhandle->as_string();
      print length($data_org) . "\n";
      $data_org = fixbase64($data_org);
      print length($data_org) . "\n";
      writefile("/tmp/test.b64",$data_org);
      $data_bin = decode_base64($data_org);
      print length($data_bin) . "\n";
    }
  }
}

sub writefile{
  my $file = shift;
  my $data = shift;
  open(HANDLE,">$file");
  local($/) = undef;
  binmode HANDLE;
  print HANDLE $data;
  close(HANDLE);
}

sub fixbase64{
        my $str = shift;
        my $res = "";
        $str =~ tr|A-Za-z0-9+=/||cd;
        while ($str =~ /(.{1,76})/gs) {
                $res .= $1 . "\n";
        }
        return $res;
}

sub decode_base64{
  local($^W) = 0;
  my $str = shift;
  my $res = "";
  $str =~ tr|A-Za-z0-9+=/||cd;
  if (length($str) % 4) {
    warn("Length of base64 data ["
         . length($str) . "] not a multiple of 4");
  }
  $str =~ s/=+$//;
  $str =~ tr|A-Za-z0-9+/| -_|;
  while ($str =~ /(.{1,60})/gs) {
    my $len = chr(32 + length($1)*3/4);
    $res .= unpack("u", $len . $1 );
  }
  return $res;
}
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