#!/usr/bin/perl
#
#   simple fbox recovery tool
#
#   Copyright (C) 2004,2005 Enrik Berkhan <enrik.berkhan@inka.de>
#   Copyright (C) 2006 Daniel Eiband <eiband@online.de>
#   changes based on adam2flash.pl (OpenWRT) from Felix Fietkau
#
#   This program is free software; you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation; either version 2 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the Free Software
#   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#

use IO::Socket::INET;
use IO::Select;
use Socket;
use Getopt::Std;
use Errno qw(EEXIST);
use Net::FTP;
use Fcntl qw(SEEK_END SEEK_SET);

my $do_crc = 1;

BEGIN {
	eval { require Compress::Zlib };
	if ($@) {
		eval { require String::CRC32 };
		if ($@) {
			print STDERR "No crc32() implementation available!\nInstall Compress::Zlib or String::CRC32 if you want CRC support.\n";
			$do_crc = 0;
		} else {
			import String::CRC32 qw(crc32);
		}
	} else {
		import Compress::Zlib qw(crc32);
	}
}

use warnings;

$| = 1;

my %opt;
getopts('hrf:i:l:ud', \%opt);

if ($opt{h}) {
	print "usage: recover -h\n";
	print "       recover [-l IPADDR] [-i IPADDR] [-f firmeware.image] [-r] [-d]\n";
	print "       recover [-l IPADDR] [-i IPADDR] -u [-d]\n";
	print "       -i IPADDR: set boot time IP to IPADDR within environment\n";
	print "       -l IPADDR: choose local addr (for multihomed)\n";
	print "       -f image:  extract fs and kernel from tarfile and flash\n";
	print "       -d:        disable crc check\n";
	print "       -r:        reboot fbox\n";
	print "       -u:        update box with filesystem.image, kernel.image from cwd\n";
	exit;
}

my $ipaddr;
my $setip;
if ($opt{i}) {
	$setip = unpack("N", inet_aton($opt{i}));
} else {
	$setip = 0;
}

if ($opt{d}) {
	$do_crc = 0;
}

$opt{l} = "0.0.0.0" unless defined $opt{l};
my $probe = IO::Socket::INET->new(Proto => 'udp',
			Broadcast => 1,
			LocalAddr => $opt{l},
			LocalPort => 5035) or die "socket: $!\n";
my $sel = IO::Select->new($probe);
my $packet = pack("vCCVNV", 0, 18, 1, 1, 0, 0);
my $broadcast = sockaddr_in(5035, INADDR_BROADCAST);

$probe->send($packet, 0, $broadcast);

scan_again:
print "looking for boxes ";
@boxes = ();
$scanning = 20;
print ".";

while($scanning) {
	my $reply;
	my @ready;

	if (@ready = $sel->can_read(0.2)) {
		$peer = $probe->recv($reply, 16);
		next if (length($reply) < 16);
		my ($port, $addr) = sockaddr_in($peer);
		my ($major, $minor1, $minor2, $code, $addr2) = unpack("vCCVV", $reply);
		$addr2 = pack("N", $addr2);
		if ($code == 2) {
			push @boxes, [$major, $minor1, $minor2, $addr, $addr2];
			$scanning = 2 if ($scanning > 2);
		}
	} else {
		$scanning--;
		if (scalar @boxes == 0) {
			$probe->send($packet, 0, $broadcast);
			print ".";
		}
	}
}

if (scalar @boxes == 0) {
	print " none found, giving up.\n";
	exit 1;
} else {
	print " found.\n";
}

foreach $box (@boxes) {
	my ($major, $minor1, $minor2, $addr, $addr2) = @$box;
	printf "ADAM2 version $major.$minor1.$minor2 at %s (%s)\n",
				 inet_ntoa($addr), inet_ntoa($addr2);
}

if (scalar @boxes > 1) {
	print "more than one boxes: exiting\n";
	exit 1;
}

$ipaddr = (@{$boxes[0]})[4];
if (!$ipaddr && !$setip) {
	print "box has no ip, giving up\n";
	exit 1;
}

if ($setip) {
	if ($setip != unpack('N', $ipaddr)) {
		print "setting ip address\n";
		my $setpacket = pack("vCCVNV", 0, 18, 1, 1, $setip, 0);
		$probe->send($setpacket, 0, $broadcast);
		goto scan_again;
	}
}

{
	package ADAM2FTP;
	use base qw(Net::FTP);

	# ADAM2 requires upper case commands, some brain dead firewall doesn't ;-)
	sub _USER { shift->command("USER",@_)->response() }
	sub _PASV { shift->command("P\@SW")->response() == Net::FTP::CMD_OK }

	sub _GETENV {
		my $ftp = shift;
		my ($ok, $name, $value);

		$ftp->command("GETENV",@_);
		while(length($ok = $ftp->response()) < 1) {
			my $line = $ftp->getline();
			unless (defined($value)) {
				chomp($line);
				($name, $value) = split(/\s+/, $line, 2);
			}
		}
		$ftp->debug_print(0, "getenv: $value\n")
			if $ftp->debug();
		return $value;
	}
	sub getenv {
		my $ftp = shift;
		my $name = shift;
		return $ftp->_GETENV($name);
	}

	sub _REBOOT { shift->command("REBOOT")->response() == Net::FTP::CMD_OK }
	sub reboot {
		my $ftp = shift;
		$ftp->_REBOOT;
		$ftp->close;
	}

	sub check {
		my $ftp = shift;

		delete ${*$ftp}{'net_ftp_port'};
		delete ${*$ftp}{'net_ftp_pasv'};

		my $data = $ftp->_data_cmd('CHECK' ,@_) or return undef;
		my $sum;
		if (${${*$ftp}{'net_cmd_resp'}}[0] =~ /^Flash check 0x([0-9A-F]{8})/) {
			$sum = hex($1);
		}
		$data->_close();
		return $sum;
	}
}

# passive mode connects too slowly
$ftp = ADAM2FTP->new(inet_ntoa($ipaddr), Passive => 0, Debug => 0, Timeout => 600) or die "can't open control connection\n";
$ftp->login("adam2", "adam2") or die "can't login\n";

my $pid   = $ftp->getenv('ProductID');
my $hwrev = $ftp->getenv('HWRevision');
my $fwrev = $ftp->getenv('firmware_info');
my $ulrev = $ftp->getenv('urlader-version');

$mtd0 = "filesystem.image";
$mtd1 = "kernel.image";

my $mtd0_hex = $ftp->getenv("mtd0");
my $mtd1_hex = $ftp->getenv("mtd1");

my ($mtd0_size, $mtd1_size);
$mtd0_hex =~ /^(0x\w+),(0x\w+)$/ and $mtd0_size = hex($2) - hex($1);
$mtd1_hex =~ /^(0x\w+),(0x\w+)$/ and $mtd1_size = hex($2) - hex($1);
($mtd0_size >= 0) and ($mtd1_size > 0) or die "can't read partition offsets\n";

print "\n";
print "Product ID        : $pid\n";
print "Hardware revision : $hwrev\n";
print "Urlader revision  : $ulrev\n";
print "Firmware revision : $fwrev\n";
print "\n";
printf "Flash space       : 0x%08x\n", $mtd0_size + $mtd1_size;
print "\n";

if ($opt{f}) {
	unless (-f $opt{f}) {
		die "$opt{f} not found\n";
	}
	mkdir ".recover.tmp";
	if ($! && $! != EEXIST) { die ".recover.tmp: $!\n" };

	my $tar = "tools/tar";
	system("$tar xf $opt{f} -C .recover.tmp ./var/tmp/kernel.image ./var/tmp/filesystem.image");
	if ($? >> 8) {
		die "$tar failed\n";
	} elsif ($? & 127) {
		die "$tar killed\n";
	}
	chmod 0644, ".recover.tmp/var/tmp/filesystem.image",
							".recover.tmp/var/tmp/kernel.image";

	$mtd0 = ".recover.tmp/var/tmp/filesystem.image";
	$mtd1 = ".recover.tmp/var/tmp/kernel.image";
}

if ($opt{f} || $opt{u}) {

	$ftp->command("MEDIA FLSH")->response();
	$ftp->binary();

	# hidden root boxes have mtd0 size == 0
	if (-f $mtd0 && ($mtd0_size > 0)) {
		$opt{r} = 1;
		$sum = remove_cksum($mtd0);

		print "flashing mtd0 ";
		my $dc = $ftp->stor("fs mtd0");
		$dc or die "can't open data connection\n";
		$sum = flash_image($mtd0, $dc, $mtd0_size, $do_crc);
		$dc->close();

		if ($ftp->status() == $ftp->CMD_OK) {
			if ($do_crc) {
				if (defined $sum) {
					my $flashsum = $ftp->check("fs mtd0");
					if ((!defined $flashsum) || ($sum ne $flashsum)) {
						print STDERR "bad checksum!\n";
					}
				} else {
					print STDERR "no checksum!\n";
				}
			} else {
				print STDERR "crc check disabled.\n";
			}
		} else {
			print STDERR "FAILED: ", $ftp->code(), " ", $ftp->message(), "\n";
			$opt{r} = 0;
		}
	}

	if (-f $mtd1) {
		$opt{r} = 1;
		$sum = remove_cksum($mtd1);

		print "flashing mtd1 ";
		my $dc = $ftp->stor("fs mtd1");
		$dc or die "can't open data connection\n";
		$sum = flash_image($mtd1, $dc, $mtd1_size, $do_crc);
		$dc->close();

		if ($ftp->status() == $ftp->CMD_OK) {
			if ($do_crc) {
				if (defined $sum) {
					my $flashsum = $ftp->check("fs mtd1");
					if ((!defined $flashsum) || ($sum ne $flashsum)) {
						print STDERR "bad checksum!\n";
					}
				} else {
					print STDERR "no checksum!\n";
				}
			} else {
				print STDERR "crc check disabled.\n";
			}
		} else {
			print STDERR "FAILED: ", $ftp->code(), " ", $ftp->message(), "\n";
			$opt{r} = 0;
		}
	}

}

if ($opt{r}) {
	print "\n";
	print "rebooting.\n";
	$ftp->reboot();
} else {
	$ftp->quit();
}

END {
	if ($opt{f}) {
		unlink(".recover.tmp/var/tmp/kernel.image");
		unlink(".recover.tmp/var/tmp/filesystem.image");
		rmdir(".recover.tmp/var/tmp");
		rmdir(".recover.tmp/var");
		rmdir(".recover.tmp");
	}
}

sub remove_cksum {
	my $name = shift;
	my $chksum = 0;
	my $sum;
	my $magic;

	open F, "+<$name" or die "open: $!\n";
	my $size = (stat F)[7];
	die "stat: $!\n" unless defined($size);
	if ($size >= 8) {
		seek F, -8, SEEK_END or die "seek: $!\n";
		read F, $magic, 4;
		read F, $sum, 4;
		if (unpack("V", $magic) == 0xC453DE23) {
			$size -= 8;
			truncate F, $size or die "truncate: $!\n";
		}
	}
	close F;
	return $chksum;
}

sub flash_image {
	my $name = shift;
	my $dc = shift;
	my $mtdsize = shift;
	my $do_crc = shift;

	my $chksize = $mtdsize;
	my $chksum = 0;
	my $rbytes = 1;

	my $written = 0;
	my $progress = 0;

	open F, "<$name" or die "open: $!\n";
	my $size = (stat F)[7];
	die "stat: $!\n" unless defined($size);
	die "image too big\n" unless ($size <= $mtdsize);
	while (($mtdsize > 0) and ($rbytes > 0)) {
		my $buffer;
		my $len = ($mtdsize > 1024 ? 1024 : $mtdsize);
		$rbytes = read F, $buffer, $len;
		if ($rbytes > 0) {
			my $wbytes = $dc->write($buffer, $rbytes, 600);
			$written  += $wbytes;
			$progress += $wbytes;
			while ($progress >= 64*1024) {
				$progress -= 64*1024;
				print ".";
			}
			$mtdsize -= $wbytes;
			if ($do_crc) {
				$chksize -= $rbytes;
				$chksum = crc32($buffer, $chksum);
			}
		}
	}
	close F;
	if ($written == $size) {
		print " success.\n";
	} else {
		print " failed (image size: $size; written: $written)\n";
	}
	if ($do_crc) {
		$chksize and $chksum = crc32("\xff" x $chksize, $chksum);
	}
	return $chksum;
}