#!/usr/bin/perl

# $Header: /mhub4/sources/imap-tools/purgeMbx.pl,v 1.7 2015/06/05 11:32:25 rick Exp $

############################################################################
#   Program name    purgeMbx.pl                                            #
#   Written by      Rick Sanders                                           #
#   Date            5/24/2008                                              #
#                                                                          #
#   Description                                                            #
#                                                                          #
#   This script deletes all of the messages in a user's IMAP               #
#   mailbox.                                                               #
#                                                                          #
#   purgeMbx.pl is called like this:                                       #
#       ./purgeMbx.pl -s host/user/password -m <mailbox>                   # 
#                                                                          #
#   Note that the mailbox name is case-sensitive.                          #
#                                                                          #
#   Optional arguments:                                                    #
#	-d debug                                                           #
#       -L <logfile>                                                       #
############################################################################

############################################################################
# Copyright (c) 2008 Rick Sanders <rfs9999@earthlink.net>                  #
#                                                                          #
# Permission to use, copy, modify, and distribute this software for any    #
# purpose with or without fee is hereby granted, provided that the above   #
# copyright notice and this permission notice appear in all copies.        #
#                                                                          #
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES #
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF         #
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR  #
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES   #
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN    #
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF  #
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.           #
############################################################################

use Socket;
use FileHandle;
use Fcntl;
use Getopt::Std;
use IO::Socket;
use MIME::Base64 qw(encode_base64 decode_base64 );

#################################################################
#            Main program.                                      #
#################################################################

init();

sigprc();

#  Get list of all messages on the source host by Message-Id
#
connectToHost($host, \$conn);
login($user,$pwd, $conn) or exit;

if ( $mbx eq '*' ) {
   @mailboxes = listMailboxes( '*', $conn);
} else {
   push( @mailboxes, $mbx );
}

foreach $mbx ( @mailboxes ) {
   Log("Purging the \"$mbx\" mailbox");
   @sourceMsgs = ();
   getMsgList( $mbx, \@msgs, $conn ); 
   Log("$mbx mailbox is empty") unless @msgs;
   foreach $msgnum ( @msgs ) {
     $total++;
     deleteMsg( $msgnum, $conn );
   }
   expungeMbx( $mbx, $conn ) if @msgs;

   Log("$total messages were deleted from \"$mbx\" mailbox");
}

logout( $conn );

exit;


sub init {

   $version = 'V1.0.1';
   $os = $ENV{'OS'};

   processArgs();

   #  Determine whether we have SSL support via openSSL and IO::Socket::SSL
   $ssl_installed = 1;
   eval 'use IO::Socket::SSL';
   if ( $@ ) {
      $ssl_installed = 0;
   }

   $timeout = 60 unless $timeout;

   #  Open the logFile
   #
   if ( $logfile ) {
      if ( !open(LOG, ">> $logfile")) {
         print STDOUT "Can't open $logfile: $!\n";
      } 
      select(LOG); $| = 1;
   }
   Log("\n$0 starting");
   $total=0;

}

#
#  sendCommand
#
#  This subroutine formats and sends an IMAP protocol command to an
#  IMAP server on a specified connection.
#

sub sendCommand
{
    local($fd) = shift @_;
    local($cmd) = shift @_;

    print $fd "$cmd\r\n";

    if ($showIMAP) { Log (">> $cmd",2); }
}

#
#  readResponse
#
#  This subroutine reads and formats an IMAP protocol response from an
#  IMAP server on a specified connection.
#

sub readResponse
{
    local($fd) = shift @_;

    $response = <$fd>;
    chop $response;
    $response =~ s/\r//g;
    push (@response,$response);
    if ($showIMAP) { Log ("<< $response",2); }
}

#
#  Log
#
#  This subroutine formats and writes a log message to STDERR.
#

sub Log {
 
my $str = shift;

   #  If a logile has been specified then write the output to it
   #  Otherwise write it to STDOUT

   if ( $logfile ) {
      ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime;
      if ($year < 99) { $yr = 2000; }
      else { $yr = 1900; }
      $line = sprintf ("%.2d-%.2d-%d.%.2d:%.2d:%.2d %s %s\n",
		     $mon + 1, $mday, $year + $yr, $hour, $min, $sec,$$,$str);
      print LOG "$line";
   } 
   print STDOUT "$str\n";

}

#  Make a connection to an IMAP host

sub connectToHost {

my $host = shift;
my $conn = shift;

   Log("Connecting to $host") if $debug;
   
   ($host,$port) = split(/:/, $host);
   $port = 143 unless $port;

   # We know whether to use SSL for ports 143 and 993.  For any
   # other ones we'll have to figure it out.
   $mode = sslmode( $host, $port );

   if ( $mode eq 'SSL' ) {
      unless( $ssl_installed == 1 ) {
         warn("You must have openSSL and IO::Socket::SSL installed to use an SSL connection");
         Log("You must have openSSL and IO::Socket::SSL installed to use an SSL connection");
         exit;
      }
      Log("Attempting an SSL connection") if $debug;
      $$conn = IO::Socket::SSL->new(
         Proto           => "tcp",
         SSL_verify_mode => 0x00,
         PeerAddr        => $host,
         PeerPort        => $port,
         Domain          => AF_INET,
      );

      unless ( $$conn ) {
        $error = IO::Socket::SSL::errstr();
        Log("Error connecting to $host: $error");
        warn("Error connecting to $host: $error");
        exit;
      }
   } else {
      #  Non-SSL connection
      Log("Attempting a non-SSL connection") if $debug;
      $$conn = IO::Socket::INET->new(
         Proto           => "tcp",
         PeerAddr        => $host,
         PeerPort        => $port,
      );

      unless ( $$conn ) {
        Log("Error connecting to $host:$port: $@");
        warn "Error connecting to $host:$port: $@";
        exit;
      }
   } 
   Log("Connected to $host on port $port");

}

sub sslmode {

my $host = shift;
my $port = shift;
my $mode;

   #  Determine whether to make an SSL connection
   #  to the host.  Return 'SSL' if so.

   if ( $port == 143 ) {
      #  Standard non-SSL port
      return '';
   } elsif ( $port == 993 ) {
      #  Standard SSL port
      return 'SSL';
   }
      
   unless ( $ssl_installed ) {
      #  We don't have SSL installed on this machine
      return '';
   }

   #  For any other port we need to determine whether it supports SSL

   my $conn = IO::Socket::SSL->new(
         Proto           => "tcp",
         SSL_verify_mode => 0x00,
         PeerAddr        => $host,
         PeerPort        => $port,
    );

    if ( $conn ) {
       close( $conn );
       $mode = 'SSL';
    } else {
       $mode = '';
    }

   return $mode;
}


#  trim
#
#  remove leading and trailing spaces from a string
sub trim {
 
local (*string) = @_;

   $string =~ s/^\s+//;
   $string =~ s/\s+$//;

   return;
}


#  login
#
#  login in at the source host with the user's name and password
#
sub login {

my $user = shift;
my $pwd  = shift;
my $conn = shift;

   if ( $admin_user ) {
      ($admin_user,$admin_pwd) = split(/:/, $admin_user);
      login_plain( $user, $admin_user, $admin_pwd, $conn ) or exit;
      return 1;
   }

   if ( $pwd =~ /^oauth2:(.+)/i ) {
      $token = $1;
      Log("password is an OAUTH2 token");
      login_xoauth2( $user, $token, $conn );
      return 1;
   }

   sendCommand ($conn, "1 LOGIN $user $pwd");
   while (1) {
	readResponse ( $conn );
	if ($response =~ /1 OK/i) {
		last;
	}
        if ($response =~ /^(.+) NO|^(.+) BAD/i) {
           Log ("unexpected LOGIN response: $response");
           return 0;
        }
   }
   Log("Logged in as $user") if $debug;

   return 1;
}

#  login_plain
#
#  login in at the source host with the user's name and password.  If provided
#  with administrator credential, use them as this eliminates the need for the 
#  user's password.
#
sub login_plain {

my $user      = shift;
my $admin     = shift;
my $pwd       = shift;
my $conn      = shift;

   #  Do an AUTHENTICATE = PLAIN.  If an admin user has been provided then use it.

   if ( !$admin ) {
      # Log in as the user
      $admin = $user
   }

   $login_str = sprintf("%s\x00%s\x00%s", $user,$admin,$pwd);
   $login_str = encode_base64("$login_str", "");
   $len = length( $login_str );

   # sendCommand ($conn, "1 AUTHENTICATE \"PLAIN\" {$len}" );
   sendCommand ($conn, "1 AUTHENTICATE PLAIN" );

   my $loops;
   while (1) {
        readResponse ( $conn );
        last if $response =~ /\+/;
        if ($response =~ /^1 NO|^1 BAD|^\* BYE/i) {
           Log ("unexpected LOGIN response: $response");
           exit;
        }
        $last if $loops++ > 5;
   }

   sendCommand ($conn, "$login_str" );
   my $loops;
   while (1) {
        readResponse ( $conn );

        if ( $response =~ /Microsoft Exchange/i and $conn eq $dst ) {
           #  The destination is an Exchange server
           $exchange = 1;
           Log("The destination is an Exchange server");
        }

        last if $response =~ /^1 OK/i;
        if ($response =~ /^1 NO|^1 BAD|^\* BYE/i) {
           Log ("unexpected LOGIN response: $response");
           exit;
        }
        $last if $loops++ > 5;
   }

   return 1;

}

#  login_xoauth2
#
#  login in at the source host with the user's name and an XOAUTH2 token.  
#
sub login_xoauth2 {

my $user      = shift;
my $token     = shift;
my $conn      = shift;

   #  Do an AUTHENTICATE = XOAUTH2 login

   $login_str = encode_base64("user=". $user ."\x01auth=Bearer ". $token ."\x01\x01", '');
   sendCommand ($conn, "1 AUTHENTICATE XOAUTH2 $login_str" );

   my $loops;
   while (1) {
        readResponse ( $conn );
        if ( $response =~ /^\+ (.+)/ ) {
           $error = decode_base64( $1 );
           Log("XOAUTH authentication as $user failed: $error");
           return 0;
        }
        last if $response =~ /^1 OK/;
        if ($response =~ /^1 NO|^1 BAD|^\* BYE|failed/i) {
           Log ("unexpected LOGIN response: $response");
           return 0;
        }
        $last if $loops++ > 5;
   }

   Log("login complete") if $debug;

   return 1;

}


#  logout
#
#  log out from the host
#
sub logout {

my $conn = shift;

   ++$lsn;
   undef @response;
   sendCommand ($conn, "$lsn LOGOUT");
   while ( 1 ) {
	readResponse ($conn);
	if ( $response =~ /^$lsn OK/i ) {
		last;
	}
	elsif ( $response !~ /^\*/ ) {
		Log ("unexpected LOGOUT response: $response");
		last;
	}
   }
   close $conn;
   return;
}


#  getMsgList
#
#  Get a list of messages in a mailbox
#
sub getMsgList {

my $mailbox = shift;
my $msgs    = shift;
my $conn    = shift;
my $seen;
my $empty;
my $msgnum;
my $from;
my $flags;

   trim( *mailbox );
   sendCommand ($conn, "1 SELECT \"$mailbox\"");
   undef @response;
   $empty=0;
   while ( 1 ) {
	readResponse ( $conn );
	if ( $response =~ / 0 EXISTS/i ) { $empty=1; }
	if ( $response =~ /^1 OK/i ) {
		# print STDERR "response $response\n";
		last;
	}
	elsif ( $response !~ /^\*/ ) {
		Log ("unexpected response: $response");
		# print STDERR "Error: $response\n";
		return 0;
	}
   }

   sendCommand ( $conn, "1 FETCH 1:* (uid flags internaldate body[header.fields (From Date)])");
   undef @response;
   while ( 1 ) {
	readResponse ( $conn );
	if ( $response =~ /^1 OK/i ) {
		# print STDERR "response $response\n";
		last;
	} 
        last if $response =~ /^1 NO|^1 BAD/;
   }

   @msgs  = ();
   $flags = '';
   for $i (0 .. $#response) {
	last if $response[$i] =~ /^1 OK FETCH complete/i;

        if ($response[$i] =~ /FLAGS/) {
           #  Get the list of flags
           $response[$i] =~ /FLAGS \(([^\)]*)/;
           $flags = $1;
           $flags =~ s/\\Recent//;
        }

        if ( $response[$i] =~ /INTERNALDATE/) {
           $response[$i] =~ /INTERNALDATE (.+) BODY/;
           # $response[$i] =~ /INTERNALDATE "(.+)" BODY/;
           $date = $1;
           
           $date =~ /"(.+)"/;
           $date = $1;
           $date =~ s/"//g;
        }

        # if ( $response[$i] =~ /\* (.+) [^FETCH]/ ) {
        if ( $response[$i] =~ /\* (.+) FETCH/ ) {
           ($msgnum) = split(/\s+/, $1);
        }

        if ( $msgnum && $date ) {
	   push (@$msgs, $msgnum);
           $msgnum = $date = '';
        }
   }


}

sub fetchMsg {

my $msgnum = shift;
my $mbx    = shift;
my $conn   = shift;
my $message;

   Log("   Fetching msg $msgnum...") if $debug;
   sendCommand ($conn, "1 SELECT \"$mbx\"");
   while (1) {
        readResponse ($conn);
	last if ( $response =~ /1 OK/i );
   }

   sendCommand( $conn, "1 FETCH $msgnum (rfc822)");
   while (1) {
	readResponse ($conn);
	if ( $response =~ /1 OK/i ) {
		$size = length($message);
		last;
	} 
	elsif ($response =~ /message number out of range/i) {
		Log ("Error fetching uid $uid: out of range",2);
		$stat=0;
		last;
	}
	elsif ($response =~ /Bogus sequence in FETCH/i) {
		Log ("Error fetching uid $uid: Bogus sequence in FETCH",2);
		$stat=0;
		last;
	}
	elsif ( $response =~ /message could not be processed/i ) {
		Log("Message could not be processed, skipping it ($user,msgnum $msgnum,$destMbx)");
		push(@errors,"Message could not be processed, skipping it ($user,msgnum $msgnum,$destMbx)");
		$stat=0;
		last;
	}
	elsif 
	   ($response =~ /^\*\s+$msgnum\s+FETCH\s+\(.*RFC822\s+\{[0-9]+\}/i) {
		($len) = ($response =~ /^\*\s+$msgnum\s+FETCH\s+\(.*RFC822\s+\{([0-9]+)\}/i);
		$cc = 0;
		$message = "";
		while ( $cc < $len ) {
			$n = 0;
			$n = read ($conn, $segment, $len - $cc);
			if ( $n == 0 ) {
				Log ("unable to read $len bytes");
				return 0;
			}
			$message .= $segment;
			$cc += $n;
		}
	}
   }

   return $message;

}


sub usage {

   print STDOUT "usage:\n";
   print STDOUT " purgeMbx.pl -S host/user/pwd -m <mbx>\n";
   print STDOUT " Optional arguments:\n";
   print STDOUT "    -d debug\n";
   print STDOUT "    -L <logfile>\n";
   print STDOUT "    -A <admin_user:admin_password>\n";
   exit;

}

sub processArgs {

   if ( !getopts( "dIs:L:m:hA:" ) ) {
      usage();
   }

   ($host,$user,$pwd) = split(/\//, $opt_s);

   $mbx = $opt_m;
   $admin_user = $opt_A;
   $logfile = $opt_L;
   $debug = $showIMAP = 1 if $opt_d;
   $showIMAP = 1 if $opt_I;
   usage() if $opt_h;

}

sub deleteMsg {

my $msgnum = shift;
my $conn   = shift;
my $rc;

   sendCommand ( $conn, "1 STORE $msgnum +FLAGS (\\Deleted)");
   while (1) {
        readResponse ($conn);
        if ( $response =~ /^1 OK/i ) {
	   $rc = 1;
	   Log("      Marked msg number $msgnum for delete") if $debug;
	   last;
	}

	if ( $response =~ /^1 BAD|^1 NO/i ) {
	   Log("Error setting \Deleted flag for msg $msgnum: $response");
	   $rc = 0;
	   last;
	}
   }

   return $rc;

}

sub expungeMbx {

my $mbx   = shift;
my $conn  = shift;

   print STDOUT "Purging mailbox $mbx..." if $debug;

   sendCommand ($conn, "1 SELECT \"$mbx\"");
   while (1) {
        readResponse ($conn);
        last if ( $response =~ /1 OK/i );
   }

   sendCommand ( $conn, "1 EXPUNGE");
   $expunged=0;
   while (1) {
        readResponse ($conn);
        $expunged++ if $response =~ /\* (.+) Expunge/i;
        last if $response =~ /^1 OK/;

	if ( $response =~ /^1 BAD|^1 NO/i ) {
	   print STDOUT "Error purging messages: $response\n";
	   last;
	}
   }

   $totalExpunged += $expunged;

   # print STDOUT "$expunged messages purged\n" if $debug;

}

sub dieright {
   local($sig) = @_;
   print STDOUT "caught signal $sig\n";
   logout( $conn );
   exit(-1);
}

sub sigprc {

   $SIG{'HUP'} = 'dieright';
   $SIG{'INT'} = 'dieright';
   $SIG{'QUIT'} = 'dieright';
   $SIG{'ILL'} = 'dieright';
   $SIG{'TRAP'} = 'dieright';
   $SIG{'IOT'} = 'dieright';
   $SIG{'EMT'} = 'dieright';
   $SIG{'FPE'} = 'dieright';
   $SIG{'BUS'} = 'dieright';
   $SIG{'SEGV'} = 'dieright';
   $SIG{'SYS'} = 'dieright';
   $SIG{'PIPE'} = 'dieright';
   $SIG{'ALRM'} = 'dieright';
   $SIG{'TERM'} = 'dieright';
   $SIG{'URG'} = 'dieright';
}

#  getMailboxList
#
#  get a list of the user's mailboxes
#
sub getMailboxList {

my $conn = shift;
my @mbxs;
my $mbx;

   #  Get a list of the user's mailboxes
   #
   Log("Get list of user's mailboxes") if $debug;

   sendCommand ($conn, "1 LIST \"\" *");
   undef @response;
   while ( 1 ) {
	readResponse ($conn);
	if ( $response =~ /^1 OK/i ) {
		last;
	}
	elsif ( $response !~ /^\*/ ) {
		Log ("unexpected response: $response");
		return 0;
	}
   }

   undef @mbxs;
   for $i (0 .. $#response) {
	$response[$i] =~ s/\s+/ /;
	($dmy,$mbx) = split(/"\/"/,$response[$i]);
	$mbx =~ s/^\s+//;  $mbx =~ s/\s+$//;
	$mbx =~ s/"//g;

	if ($response[$i] =~ /NOSELECT/i) {
		if ($debugMode) { Log("$mbx is set NOSELECT,skip it",2); }
		next;
	}
	if ($mbx =~ /^\./) {
		# Skip mailboxes starting with a dot
		next;
	}
	push ( @mbxs, $mbx ) if $mbx ne '';
   }

   return @mbxs;
}

#  listMailboxes
#
#  Get a list of the user's mailboxes
#
sub listMailboxes {

my $mbx  = shift;
my $conn = shift;
my @mbxs;

   sendCommand ($conn, "1 LIST \"\" \"$mbx\"");
   undef @response;
   while ( 1 ) {
        &readResponse ($conn);
        if ( $response =~ /^1 OK/i ) {
                last;
        }
        elsif ( $response !~ /^\*/ ) {
                &Log ("unexpected response: $response");
                return 0;
        }
   }

   @mbxs = ();
   for $i (0 .. $#response) {
        $response[$i] =~ s/\s+/ /;
        if ( $response[$i] =~ /"$/ ) {
           $response[$i] =~ /\* LIST \((.*)\) "(.+)" "(.+)"/i;
           $mbx = $3;
        } elsif ( $response[$i] =~ /\* LIST \((.*)\) NIL (.+)/i ) {
           $mbx   = $2;
        } else {
           $response[$i] =~ /\* LIST \((.*)\) "(.+)" (.+)/i;
           $mbx = $3;
        }
        $mbx =~ s/^\s+//;  $mbx =~ s/\s+$//;

        if ($response[$i] =~ /NOSELECT/i) {
           $nosel_mbxs{"$mbx"} = 1;
        }
        push ( @mbxs, $mbx ) if $mbx ne '';
   }

   return @mbxs;
}