+ Moshe Kaminsky <[EMAIL PROTECTED]> [30/09/03 22:20]: > This whole thing means I'll need some extra program to verify such > e-mails, but I guess no one knows where I can find it. I guess I'll > just have to use perl's MIME::Tools.
Well, I wrote something. I attach it in case someone else needs it (it's useful with procmail). > Thanks anyway, > Moshe > > > > > -- > > Nadav Har'El | Monday, Sep 29 2003, 3 Tishri 5764 > > [EMAIL PROTECTED] |----------------------------------------- > > Phone: +972-53-790466, ICQ 13349191 |If you lost your left arm, your right arm > > http://nadav.harel.org.il |would be left. > > > > ================================================================= > > To unsubscribe, send mail to [EMAIL PROTECTED] with > > the word "unsubscribe" in the message body, e.g., run the command > > echo unsubscribe | mail [EMAIL PROTECTED] > > > > -- > Moshe Kaminsky <[EMAIL PROTECTED]> > Home: 08-9456841 > > ================================================================= > To unsubscribe, send mail to [EMAIL PROTECTED] with > the word "unsubscribe" in the message body, e.g., run the command > echo unsubscribe | mail [EMAIL PROTECTED] > -- Moshe Kaminsky <[EMAIL PROTECTED]> Home: 08-9456841
#!/usr/bin/env perl
# File Name: mailverify
# Maintainer: Moshe Kaminsky <[EMAIL PROTECTED]>
# Original Date: September 30, 2003
# Last Update: September 30, 2003
###########################################################
use warnings;
use integer;
BEGIN {
our $VERSION = 0.1;
# analyze command line
use Getopt::Long qw(:config gnu_getopt);
use Pod::Usage;
our $opt_help;
our $opt_man;
our $opt_version;
our $Gpg;
our $Tolerant;
GetOptions('gpg=s' => \$Gpg,
'tolerant!' => \$Tolerant,
'help', 'version', 'man');
pod2usage(1) if $opt_help;
pod2usage(-verbose => 2) if $opt_man;
print "$0 version $VERSION\n" and exit if $opt_version;
$Gpg = '/usr/local/bin/gpg --batch --verify' unless $Gpg;
}
use File::Temp qw( tempfile );
my $PrevField = '';
# process the header
while (<>) {
next if /^From /o;
last if /^$/o;
if (/^([\w-]+): (.*)$/o) {
$Header{$1} = $2;
$PrevField = $1;
} else {
$Header{$PrevField} .= $_;
}
}
# check that the message is signed
$Str = $Header{'Content-Type'};
@Parts = split /;\s+/, $Str if $Str;
if (not $Str or $Parts[0] ne 'multipart/signed') {
# the message is not multipart/signed, but might still be cleartext
# signed. Depending on --tolerant, we may pass the rest of the message to
# gpg directly
print "Message not signed\n" and exit -1 unless $Tolerant;
open GPG, "|$Gpg" or die "Can't open pipe to gpg ($Gpg): $!";
print GPG <>;
close GPG;
exit $? >> 8;
}
# the boundary string signals the boundary between two attachments
$Boundary = $1 if $Parts[3] =~ /^boundary="(.*)"$/o;
# go to the start of the message
while (<>) {
last if $_ eq "--$Boundary\n";
}
# read the message, excluding the last (empty) line
while (<>) {
last if $_ eq "--$Boundary\n";
push @Message, $_;
}
pop @Message;
# read the sig
while (<>) {
last if /^-----BEGIN PGP SIGNATURE-----$/o;
}
{
do {
push @Sig, $_;
last if /^-----END PGP SIGNATURE-----$/o;
} while (<>);
};
# here comes the funny part: replace \n by \r\n
$_ = join '', @Message;
s/(?<!\r)\n/\r\n/g;
# write everything to files
my ($MsgFH, $MsgFile) = tempfile;
print $MsgFH $_;
my $SigFile = "$MsgFile.asc";
open SIGFH, ">$SigFile" or die "can't open $SigFile: $!";
print SIGFH @Sig;
close $MsgFH;
close SIGFH;
# run gpg
print `$Gpg $SigFile`;
# clean up
unlink $MsgFile, $SigFile;
# exit with the status of gpg
exit $? >> 8;
__DATA__
# start of POD
=head1 NAME
mailverify - verify the pgp signature of a mime signed mail message
=head1 SYNOPSIS
B<mailverify> B<--help>|B<--man>|B<--version>
B<mailverify> [B<--gpg=I<gpg command>>] [B<--(no)tolerant>] [I<mail file>]
=head1 OPTIONS
=over 4
=item B<--gpg=I<gpg command>>
The command to run to do the actual checking. The default is
S<C</usr/local/bin/gpg --batch --verify>>. It is called with one argument,
which is the name of the file containing the signature. If B<--tolerant> is
used, it may also be called with the whole message on the standard input.
=item B<--(no)tolerant>
Normally (with B<--notolerant>), if the Content-Type is not
C<multipart/signed>, B<mailverify> decides that the message is not signed,
and exits with status -1. With this switch, the message is passed to I<gpg>
(or whatever was specified with the B<--gpg> option) as is. This way,
clearsigned messages can be verified with the same command.
=item B<--help>
Give a short usage message and exit with status 1
=item B<--man>
Give the full description and exit with status 1
=item B<--version>
Print a line with the program name and exit with status 0
=back
=head1 ARGUMENTS
If an argument is given, it is treated a file containing an e-mail message to
verify, but more common is to read the message from stdin.
=head1 DESCRIPTION
This script verifies the pgp signature of files whose signature appears as an
attachment (Content-Type C<multipart/signed>). If B<--tolerant> is used, it
will also verify clearsigned messages. The usage is basically to pipe the
mail to this program.
=head1 EXIT STATUS
If the message is not of type C<multipart/signed>, and B<--tolerant> is not
given, the exit status is -1. In any other case, it is the exit status of the
I<gpg> command.
=head1 SEE ALSO
I<gpg(1)>
=head1 BUGS
Probably plenty, since I don't read any RFCs. Works with all cases I checked,
though.
=head1 AUTHOR
Moshe Kaminsky <[EMAIL PROTECTED]> - Copyright (c) 2003
=head1 LICENSE
This program is free software. You may copy or
redistribute it under the same terms as Perl itself.
=cut
pgp00000.pgp
Description: PGP signature
