#!/usr/bin/perl -w

use strict;

$| = 1;

######################################################
# NAI VirusScan DAT file auto updater
# November 2002, Bas Rijniersce, bas@brijn.nu
#             Guillaume Beaudoin, soli@soli.ca (minor contributions)

my $version = "0.4";

# Set verbose to tune output (useful for cron use)
my $verbose = 0;
#$verbose = 0;	# No output at all! Not even on the most serious warning, not recommended
#$verbose = 1;	# Serious warnings
#$verbose = 2;	# On update only 
#$verbose = 3;	# Verbose output
#$verbose = 4;	# Even more
$verbose = 5;	# Debug output

# Location of the required files
my $lynx = "/usr/bin/lynx";
my $unzip = "/usr/bin/unzip";
my $md5sum = "/usr/bin/md5sum";
my $naiurl = "ftp://ftp.nai.com";
my $iniurl = "ftp://ftp.nai.com/pub/datfiles/english/update.ini";
my $datdir = "/usr/local/uvscan";
my $binary = "/usr/local/uvscan/uvscan";
my $wget = "/usr/bin/wget";  
my $tar = "/bin/tar";
my $ls = "/bin/ls";
my $rm = "/bin/rm";

# Initialize variables
my $cur_dat_vers = 0;
my $dat_file_name = "";
my $dat_file_path = ""; 
my $rem_dat_vers = 0;
my $cur_eng_vers = 0;
my $eng_file_name = "";
my $eng_file_path = "";
my $rem_eng_vers = 0;
my $rem_dat_md5 = 0;
my $rem_eng_md5 = 0;
my $res_md5 = -1;
my $res = 0;
my $tmp = 0;
my $zipfound = 0;
my $enginefound = 0;
my $result = "";

# Tell who we are
print "Naiupdt $version <bas\@brijn.nu> and <soli\@soli.ca>\n\n" if ($verbose >= 3);

# Do some checking on needed binaries
# Assuming that ls and rm are in their default locations (valid on != Linux?)
print "Checking for tar ..\t\t\t\t" if ($verbose >= 3);
if (!(-x $tar)) {
	print "Tar ($tar) not found, can't continue\n" if ($verbose >= 1);
  	exit(1);
} else {
	print "OK\n" if ($verbose == 3);
	print "OK ($tar)\n" if ($verbose >= 4);
}

print "Checking for lynx ..\t\t\t\t" if ($verbose >= 3);
if (!(-x $lynx)) {
	print "Lynx ($lynx) not found, can't continue\n" if ($verbose >= 1);
	exit(1);
} else {
	print "OK\n" if ($verbose == 3);
	print "OK ($lynx)\n" if ($verbose >= 4);
}

print "Checking for wget ..\t\t\t\t" if ($verbose >= 3);
if (!(-x $wget)) {
	print "Wget ($wget) not found, can't continue\n" if ($verbose >= 1);
  	exit(1);
} else {
	print "OK\n" if ($verbose == 3);
	print "OK ($wget)\n" if ($verbose >= 4);
}

print "Checking for unzip ..\t\t\t\t" if ($verbose >= 3);
if (!(-x $unzip)) {
	print "Unzip ($unzip) not found, can't continue\n" if ($verbose >= 1);
	exit(1);
} else {
	print "OK\n" if ($verbose == 3);
	print "OK ($unzip)\n" if ($verbose >= 4);
}

print "Checking DAT directory ..\t\t" if ($verbose >= 3);
if (!(-w $datdir)) {
        print "DAT dir ($datdir) not found or writable, can't continue\n" if ($verbose >= 1);
        exit(1);
} else {
	print "OK\n" if ($verbose == 3);
	print "OK ($datdir)\n" if ($verbose >= 4);
}

print "Checking uvscan binary ..\t\t" if ($verbose >= 3);
if (!(-x $binary)) {
	print "Uvscan binary ($binary) not found, can't continue\n" if ($verbose >= 1);
	exit(1);
} else {
	print "OK\n" if ($verbose == 3);
	print "OK ($binary)\n" if ($verbose >= 4);
}

# Get local versions by querying binary
open (LOCAL, "$datdir/uvscan --version |");
while (<LOCAL>) {
	if ( $_ =~ /.*data file v(\d+) /) {
		$cur_dat_vers = $1;
	}
	if ( $_ =~ /.*engine v(\d+\.\d+\.\d+) /) {
		$cur_eng_vers = $1;
		$cur_eng_vers =~ s/\.//g;
	}
}
close (LOCAL);
print "Checking local Engine version ..\t$cur_eng_vers\n" if ($verbose == 3);
print "Checking local Engine version ..\tOK ($cur_eng_vers)\n" if ($verbose >= 4);
print "Checking local DAT version ..\t\t$cur_dat_vers\n" if ($verbose == 3);
print "Checking local DAT version ..\t\tOK ($cur_dat_vers)\n" if ($verbose >= 4);

print "\n" if ($verbose >= 3);

# Get remote version by querying update.ini
print "Downloading update.ini ..\t\t" if ($verbose >= 3);
open (LYNX, "TERM=vt100 $lynx -term=vt100 -dump $iniurl 2>&1 |"); # Lynx needs term type
while (<LYNX>) {
	chomp;
	if (/Alert/g) {
                print "FAIL\n\n";
		print "Unable to connect to $iniurl .. maybe more luck on next run\n" if ($verbose >= 1);
                exit(1);
        }

	# A new section has started or the current section ended
	if (/^\[.*\]$|^$/) {
		$zipfound = 0;
		$enginefound = 0;
	}

	# The update.ini file has a section called [ZIP] for the DAT file    
	if (/^\[ZIP\]$/) { $zipfound = 1; }
	
	if (/^DATVersion=(\d+).*/ and $zipfound) {
		$rem_dat_vers = $1;
	}
	if (/^FileName=(.*)/ and $zipfound ) { #\w*-\d*\.\w*
		$dat_file_name = $1;
	}
	if (/^FilePath=(.*)/ and $zipfound) {
		$dat_file_path = $1;
	}
	if (/^MD5=(.*)/ and $zipfound) {
		$rem_dat_md5 = $1;
	}
	# The update.ini has a section called Engine-LINUX for the engine file
        if (/^\[Engine-LINUX\]$/) { $enginefound = 1; }

	if (/^EngineVersion=(\d+).*/ and $enginefound) {
        	$rem_eng_vers = $1;
	}
        if (/^FileName=(.*)/ and $enginefound) {
                $eng_file_name = $1;
	}
        if (/^FilePath=(.*)/ and $enginefound) {
                $eng_file_path = $1;
        }
	if (/^MD5=(.*)/ and $enginefound) {
		$rem_eng_md5 = $1;
	}
}
close(LYNX);
print "SUCCESS\n" if ($verbose >= 3);

print "Checking remote Engine version ..\t$rem_eng_vers\n" if ($verbose == 3);
print "Checking remote Engine version ..\tOK ($rem_eng_vers)\n" if ($verbose >= 4);
print "Checking remote DAT version ..\t\t$rem_dat_vers\n" if ($verbose == 3);
print "Checking remote DAT version ..\t\tOK ($rem_dat_vers)\n" if ($verbose >= 4);

print "\n" if ($verbose >= 3);

if ($rem_eng_vers > $cur_eng_vers) {
	print "Make a backup copy ..\n" if ($verbose >= 3);
	$res = system("cd $datdir;mkdir -p backup;cp liblnxfv.so.4 license.dat messages.dat backup > /dev/null 2>&1");
	print "Downloading newer Engine file ..\t" if ($verbose >= 3);
	print "Executing ..\n$wget --passive-ftp -T 300 -q -nc $naiurl$eng_file_path$eng_file_name .. " if ($verbose >= 5);
	$res = system("cd $datdir; $wget --passive-ftp -T 300 -q -nc $naiurl$eng_file_path$eng_file_name > /dev/null 2>&1");
	if ($res != 0) {
		# Download failed somehow, notify and remove downloaded file
		print "FAIL\n\n" if ($verbose >= 3);
		print "Download of Engine file failed .. maybe more luck on next run\n\n" if ($verbose >= 1);
		print "Cleaning up ..\t\t\t\t" if ($verbose >= 3);
		$res = system("cd $datdir; $rm -f $eng_file_name > /dev/null 2>&1");
		if ($res != 0) {
			print "FAIL\n\n" if ($verbose >= 3);
			print "Remove of DAT file failed .. Remove manually\n\n" if ($verbose >= 1);
		} else { print "DONE\n" if ($verbose >= 3); }
		exit(1);
	}
	# File received OK
	print("\tSUCCESS\n") if ($verbose >= 3);

	if (-x $md5sum) {
		print("Checking MD5 signature ..\t\t") if ($verbose >= 3);
		open (MD5, "$md5sum -b < $datdir/$eng_file_name 2>&1 |") or die;
		while (<MD5>) {
			if (/^(\w{32})/) {
				$res_md5 = $1;
			}
		}
		close (MD5);
		if ($rem_eng_md5 ne $res_md5) {
			print "FAIL\n\n" if ($verbose >= 3);
			print("DAT file MD5 signature does not match\n\n") if ($verbose >= 1);
			exit(1);
		}
		print "OK\n" if ($verbose == 3);
		print "OK ($res_md5)\n" if ($verbose >= 4);
	} else {
		print("MD5 signature of Engine file ignored, $md5sum not found ..\n") if ($verbose >= 1);
	}

	print("Unpacking Engine file ..\t\t") if ($verbose >= 3);
	print("Executing ..\n$unzip -o $eng_file_name .. ") if ($verbose >= 5);
	$res = system("cd $datdir; $unzip -o $eng_file_name > /dev/null 2>&1");
	if ( ($res != 2304) and ($res !=0) ) {				# WARNING: Very weird return code for success!!
		print "FAIL\n\n" if ($verbose >= 3);
		print "Unpacking of Engine file failed ..\n\n"  if ($verbose >= 1);
		print "Cleaning up .. \t\t\t\t" if ($verbose >= 3);
		$res = system("cd $datdir; $rm -f $eng_file_name > /dev/null 2>&1");
		if ($res != 0) {
			print "FAIL\n\n" if ($verbose >= 3);
			print "Remove of Engine file failed .. Remove manually\n\n" if ($verbose >= 1);
		} else { print "DONE\n" if ($verbose >= 3); }
		exit(1);
	}
	print "\tSUCCESS\n" if ($verbose >= 3);
	print("Cleaning up Engine file ..\t\t") if ($verbose >= 3);
	$res = system("cd $datdir; rm -f $eng_file_name > /dev/null 2>&1");
	if ($res != 0) {
		print "FAIL\n\n" if ($verbose >= 3);
		print "Remove of Engine file failed .. Remove manually\n\n" if ($verbose >= 1);
		exit(2);
	}
	print "DONE\n" if ($verbose >= 3);
	print "Engine updated from $cur_eng_vers to $rem_eng_vers ..\tSUCCESSFUL\n" if ($verbose >= 2);
} else {
	print ("Your Engine file is up to date ..\tOK\n") if ($verbose == 3);
	print ("Your Engine file is up to date ..\tOK ($cur_eng_vers)\n") if ($verbose >= 4);
}

print "\n" if ($verbose >= 3);

if ($rem_dat_vers > $cur_dat_vers) {
	print "Make a backup copy ..\n" if ($verbose >= 3);
	$res = system("cd $datdir;mkdir -p backup;cp names.dat scan.dat backup > /dev/null 2>&1");

	print "Downloading newer DAT file ..\t\t" if ($verbose >= 3);
	print "Executing ..\n$wget --passive-ftp -T 300 -q -nc $naiurl$dat_file_path$dat_file_name .. " if ($verbose >= 5);
	$res = system("cd $datdir; $wget --passive-ftp -T 300 -q -nc $naiurl$dat_file_path$dat_file_name > /dev/null 2>&1");
	if ($res != 0) {
		# Download failed somehow, notify and remove downloaded file
		print "FAIL\n\n" if ($verbose >= 3);
		print "Download of DAT file failed .. maybe more luck on next run\n\n" if ($verbose >= 1);
		print "Cleaning up ..\t\t\t\t" if ($verbose >= 3);
		$res = system("cd $datdir; $rm -f $dat_file_name > /dev/null 2>&1");
		if ($res != 0) {
			print "FAIL\n\n" if ($verbose >= 3);
			print "Remove of DAT file failed .. Remove manually\n\n" if ($verbose >= 1);
		} else { print "DONE\n" if ($verbose >= 3); }
		exit (1);
	}
	# File received OK
	print("SUCCESS\n") if ($verbose >= 3);

	if (-x $md5sum) {
		print("Checking MD5 signature ..\t\t") if ($verbose >= 3);
		open (MD5, "$md5sum -b < $datdir/$dat_file_name 2>&1 |") or die;
		while (<MD5>) {
			if (/^(\w{32})/) {
                                $res_md5 = $1;
                        }
		}
		close (MD5);
		if ($rem_dat_md5 ne $res_md5) {
			print "FAIL\n\n" if ($verbose >= 3);
			print("DAT file MD5 signature does not match\n\n") if ($verbose >= 1);
			exit(1);
		}
		print "OK\n" if ($verbose == 3);
		print "OK ($res_md5)\n" if ($verbose >= 4);
	} else {
		print("MD5 signature of DAT file ignored, $md5sum not found ..\n") if ($verbose >= 1);
	}

	print("Unpacking DAT file ..\t\t\t") if ($verbose >= 3);
	print("Executing ..\n$unzip -o $dat_file_name .. ") if ($verbose >= 5);
	$res = system("cd $datdir; $unzip -o $dat_file_name > /dev/null 2>&1");
	if ( ($res != 2304) and ($res !=0) ) {				# WARNING: Very weird return code for success!!
		print "FAIL\n\n" if ($verbose >= 3);
		print "Unpacking of DAT file failed ..\n\n"  if ($verbose >= 1);
		print "Cleaning up .. \t\t\t\t" if ($verbose >= 3);
		$res = system("cd $datdir; $rm -f $dat_file_name > /dev/null 2>&1");
		if ($res != 0) {
			print "FAIL\n\n" if ($verbose >= 3);
			print "Remove of DAT file failed .. Remove manually\n\n" if ($verbose >= 1);
		} else { print "DONE\n" if ($verbose >= 3); }
		exit(1);
	}
	print "\tSUCCESS\n" if ($verbose >= 3);
	print("Cleaning up DAT file ..\t\t\t") if ($verbose >= 3);
        print("Fixing DAT file permissions ..\nchmod 755 $datdir/*.dat .. ") if ($verbose >= 5);
        $res = system("cd $datdir; chmod 755 *.dat > /dev/null 2>&1");
        if ($res != 0) {
                print "FAIL\n\n" if ($verbose >= 3);
                print "DAT file permission change failed .. Change manually\n\n" if ($verbose >= 1);
                exit(2);
        }
	$res = system("cd $datdir; rm -f $dat_file_name > /dev/null 2>&1");
	if ($res != 0) {
		print "FAIL\n\n" if ($verbose >= 3);
		print "Remove of DAT file failed .. Remove manually\n\n" if ($verbose >= 1);
		exit(2);
	}
	print "DONE\n" if ($verbose >= 3);
	print "DAT updated from $cur_dat_vers to $rem_dat_vers ..\t\tSUCCESSFUL\n" if ($verbose >= 2);
	if ($verbose >= 2) {
		open (README, "$datdir/readme.txt");
		read (README, $tmp, 50000);
		if ($tmp =~ /={40}.*?(\w{4} Emergency Dat Release.*?)[^=]{2}={40}/s) {
			print "\n*************  EMERGENCY DAT RELEASE  **************\n\n";
			print "$1";
			print "\n*************  EMERGENCY DAT RELEASE  **************\n";
		}
		close (README);
	}
} else {
	print ("Your DAT file is up to date ..\t\tOK\n") if ($verbose == 3);
	print ("Your DAT file is up to date ..\t\tOK ($cur_dat_vers)\n") if ($verbose >= 4);
}


if ($verbose >= 1) {
	print "\nPerforming a scan test ..\t\t" if ($verbose >= 3);

	open (VIRUS,"> $datdir/eicar.com");
	print VIRUS "X5O!P%\@AP[4\\PZX54(P^)7CC)7}\$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!\$H+H*";
	close VIRUS;

	$res = 1;
	open (VIRUS, "$binary --noboot $datdir/eicar.com 2>&1 |");
	while (<VIRUS>) {
		$res = 0 if (/EICAR/);
	}
	close (VIRUS);

	if ($res == 1) {
		print "FAIL\n\n" if ($verbose >= 3);
		print "**************  SYSTEM IS NOT SECURE  **************\n";
		print "***                                              ***\n";
		print "***           Standard EICAR test fail           ***\n";
		print "***       Your system is not virus secure        ***\n";
		print "***                                              ***\n";
		print "**************  SYSTEM IS NOT SECURE  **************\n\n";
		print "Restoring original files!\n";
		
		$res = system("cd $datdir;mv backup/* .;rm -rf backup"); 
	
	} else {
		print "SUCCESSFUL\n" if ($verbose >= 3);
	}
	system("cd $datdir; rm -f $datdir/eicar.com;rm -rf backup");
}