scripts/flashing/adam2flash-502T.pl - T108 - Gitiles

 #!/usr/bin/env perl
 #
 #   D-Link DSL-502T flash utility
 #
 #   Copyright (c) 2007 Oliver Jowett <oliver@opencloud.com>
 #
 #   Based on adam2flash.pl for the D-Link DSL-G6x4T, which is:
 #   Copyright (C) 2005 Felix Fietkau <mailto@nbd.name>
 #   based on fbox recovery util by Enrik Berkhan
 #
 #   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
 #

 # The default DSL-502T mtd map looks like this:
 #
 # mtd0 0x90091000,0x903f0000    # filesystem
 # mtd1 0x90010090,0x90091000    # kernel
 # mtd2 0x90000000,0x90010000    # bootloader - DO NOT MODIFY
 # mtd3 0x903f0000,0x90400000    # config space - DO NOT MODIFY
 # mtd4 0x90010000,0x903f0000    # firmware signature + kernel + filesystem, used to flash new firmware
 #
 # i.e. the flash layout is:
 #
 # 90000000-9000FFFF mtd2 bootloader
 # 90010000-9001008F ---- firmware signature )
 # 90010090-90090FFF mtd1 kernel             ) mtd4 spans these three regions
 # 90091000-903EFFFF mtd0 filesystem         )
 # 903F0000-903FFFFF mtd3 config space
 #
 # The ADAM2 bootloader uses the mtd1 settings to find the start of the image to boot.
 # The image to load contains information about the loadable size of the image. If ADAM2 sees
 # that the image appears to extend beyond the end of mtd1, it will refuse to load it. On
 # the DSL-502T, this manifests as the USB light blinking rapidly on boot.
 #
 # The OpenWRT kernel does not follow quite the same layout:
 #  (a) it does not have a 0x90-byte firmware signature prefix
 #  (b) it is larger than the default mtd1 size
 #
 # (a) would be avoidable (build a custom image with a 0x90-byte prefix) but (b) is unavoidable.
 # So we *have* to change mtd1. The simplest thing to do seems to make it span all of
 # the flashable area, producing this layout:
 #
 # mtd0 0x90091000,0x903f0000    # filesystem
 # mtd1 0x90010000,0x903f0000    # kernel (CHANGED)
 # mtd2 0x90000000,0x90010000    # bootloader - DO NOT MODIFY
 # mtd3 0x903f0000,0x90400000    # config space - DO NOT MODIFY
 # mtd4 0x90010000,0x903f0000    # kernel + filesystem, used to flash new firmware
 #
 # *** NOTE NOTE NOTE NOTE ***
 #
 # /dev/mtd0 .. /dev/mtd4 when using OpenWRT do **NOT** correspond to the ADAM2 mtd0-4 settings!
 # Instead, OpenWRT scans the MTD itself and determines its own boundaries which are arranged
 # quite differently to ADAM2. It will look something like this, see dmsg on boot:
 #
 # (/dev/mtd0) 0x00000000-0x00010000 : "loader"        # Bootloader, read-only
 # (/dev/mtd1) 0x003f0000-0x00400000 : "config"        # Config space
 # (/dev/mtd2) 0x00010000-0x003f0000 : "linux"         # Firmware area (kernel + root fs + JFFS area)
 # (/dev/mtd3) 0x000d0d58-0x003f0000 : "rootfs"        # Root FS, starts immediately after kernel
 # (/dev/mtd4) 0x00280000-0x003f0000 : "rootfs_data"   # If rootfs is squashfs, start of JFFS area.
 #
 # All of those boundaries are autodetected by examining the data in flash.
 #
 # *** NOTE NOTE NOTE NOTE ***

 use IO::Socket::INET;
 use Socket;
 use strict;
 use warnings;

 sub usage() {
 	print STDERR "Usage: $0 <ip> [-setmtd1] [-noflash] [firmware.bin]\n\n";
 	print STDERR "Acquires the ADAM2 bootloader of a D-Link DSL-504T at <ip>\n";
 	print STDERR "Power off the device, start this script, then power it on.\n";
 	print STDERR "<ip> may be any spare address on the local subnet.\n\n";
 	print STDERR "If a firmware file is specified, MTD settings are verified and\n";
 	print STDERR "then the firmware is written to the router's flash.\n";
 	print STDERR "The firmware type (D-Link or OpenWRT) is automatically detected.\n\n";
 	print STDERR "  -setmtd1  update mtd1 if it is not the appropriate value for this firmware\n";
 	print STDERR "  -noflash  does normal checks, updates mtd1 if requested, but does not actually write firmware\n\n";
 	exit 0;
 }

 my $ip = shift @ARGV;
 $ip and $ip =~ /\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}/ or usage();

 my $probe = IO::Socket::INET->new(Proto => 'udp',
                                   Broadcast => 1,
                                   LocalPort => 5035) or die "socket: $!";
 my $setip = unpack("N", inet_aton($ip));
 $setip > 0 or usage();

 my @packets;
 foreach my $ver ([18, 1], [22, 2]) {
 	push @packets, pack("vCCVNV", 0, @$ver, 1, $setip, 0);
 }
 print STDERR "Looking for device: ";
 my $broadcast = sockaddr_in(5035, INADDR_BROADCAST);
 my $scanning;
 my $box;

 $SIG{"ALRM"} = sub {
 	return if --$scanning <= 0;
 	foreach my $packet (@packets) {
 		$probe->send($packet, 0, $broadcast);
 	}
 	print STDERR ".";
 };

 $scanning = 15;
 foreach my $packet (@packets) {
 	$probe->send($packet, 0, $broadcast);
 }
 print STDERR ".";

 while($scanning) {
 	my $reply;

 	alarm(1);
 	if (my $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) {
 			$scanning = 0;
 			printf STDERR " found!\nADAM2 version $major.$minor1.$minor2 at %s (%s)\n", inet_ntoa($addr), inet_ntoa($addr2);
 			$box = inet_ntoa($addr);
 		}
 	}
 }

 $box or die " not found!\n";

 alarm(0);

 {
 	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 _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;
 	}
 }

 my $file;
 my $arg;
 my $noflash = 0;
 my $setmtd1 = 0;
 while ($arg = shift @ARGV) {
   if ($arg eq "-noflash") { $noflash = 1; }
   elsif ($arg eq "-setmtd1") { $setmtd1 = 1; }
   else { $file = $arg; }
 }

 if (!$file) {
   print STDERR "No firmware file specified, exiting.\n";
   exit 0;
 }

 #
 # Firmware checks
 #

 open FILE, "<$file" or die "can't open firmware file\n";

 # D-Link firmware starts with "MTD4" little-endian, then has an image header at 0x90
 # OpenWRT firmware just starts with an image header at 0x00

 my $signature;
 my $sbytes = read FILE, $signature, 4;
 ($sbytes == 4) or die "can't read firmware signature: $!";

 my $expectedmtd4 = "0x90010000,0x903f0000";
 my $fwtype;
 my $expectedmtd1;

 if ($signature eq "4DTM") {
   seek FILE, 0x90, 0 or die "can't read firmware signature: $!";
   $sbytes = read FILE, $signature, 4;
   ($sbytes == 4) or die "can't read firmware signature: $!";
   if ($signature eq "\x42\xfa\xed\xfe") {
     $fwtype = "D-Link (little-endian)";
     $expectedmtd1 = "0x90010090,0x90091000";
   } elsif ($signature eq "\xde\xad\xbe\x42") {
     $fwtype = "D-Link (big-endian)";
     $expectedmtd1 = "0x90010090,0x90091000";
   }
 } elsif ($signature eq "\x42\xfa\xed\xfe") {
   $fwtype = "OpenWRT (little-endian)";
   $expectedmtd1 = "0x90010000,0x903f0000";
 } elsif ($signature eq "\xde\xad\xbe\x42") {
   $fwtype = "OpenWRT (big-endian)";
   $expectedmtd1 = "0x90010000,0x903f0000";
 }

 $fwtype or die "Unknown firmware signature (are you sure that's the right firmware?)";
 print STDERR "Firmware type: $fwtype\n";

 #
 # Bootloader login
 #

 print STDERR "logging into ADAM2 bootloader.. ";
 my $ftp = ADAM2FTP->new($box, Debug => 0, Timeout => 600) or die "can't open control connection\n";
 $ftp->login("adam2", "adam2") or die "can't login\n";
 print STDERR "ok.\n";

 #
 # Hardware checks
 #

 print STDERR "checking hardware.. ";
 my $prd = $ftp->getenv("ProductID");
 my $usb = $ftp->getenv("usb_prod");
 print STDERR "$prd / $usb.\n";
 ($prd eq "AR7RD" || $prd eq "AR7DB") or die "doesn't look like a DSL-502T?";
 ($usb eq "DSL-502T") or die "doesn't look like a DSL-502T?";

 #
 # MTD checks and update
 #

 print STDERR "checking MTD settings.. ";

 my $mtd4 = $ftp->getenv("mtd4");
 ($mtd4 eq $expectedmtd4) or die "MTD4 was not as expected (should be '$expectedmtd4', was '$mtd4'). Cowardly refusing to do anything about it!";

 # check MTD1 setting and update if needed
 my $mtd1 = $ftp->getenv("mtd1");
 if ($mtd1 ne $expectedmtd1) {
   die "MTD1 was not as expected (should be '$expectedmtd1', was '$mtd1'). Run with -setmtd1 to reset mtd1" unless ($setmtd1);
   print STDERR "Setting mtd1.. ";
   ($ftp->command("SETENV","mtd1,$expectedmtd1")->response() == Net::FTP::CMD_OK) or die "can't set mtd1";
   $file = shift @ARGV;
 }

 print STDERR "ok.\n";

 #
 # Firmware size check
 #

 my $fwsize = (stat(FILE))[7];
 printf STDERR "Firmware size: 0x%08x\n", $fwsize;
 my $flashsize;
 $mtd4 =~ /^(0x\w+),(0x\w+)$/ and $flashsize = hex($2) - hex($1);
 printf STDERR "Available flash space: 0x%08x\n", $flashsize;
 die "firmware is too large" if ($flashsize < $fwsize);

 #
 # Flash it!
 #

 if ($noflash) {
   print STDERR "Not flashing firmware as -noflash was specified.\n";
   exit 0;
 }

 seek FILE, 0, 0, or die "can't seek in firmware: $!";

 print STDERR "Preparing to flash.. ";
 ($ftp->command("MEDIA FLSH")->response() == Net::FTP::CMD_OK) or die "can't set MEDIA FLSH";
 $ftp->binary() or die "can't set binary mode";
 print STDERR "ok.\n";
 print STDERR "Erasing flash and establishing data connection (this may take a while): ";

 my $dc = $ftp->stor("fs mtd4");
 $dc or die "can't open data connection: $!\n";
 print STDERR "ok.\n";

 print STDERR "Writing firmware: ";
 while ($fwsize > 0) {
 	my $buffer;
 	my $len = ($fwsize > 1024 ? 1024 : $fwsize);

 	my $rbytes = read FILE, $buffer, $len;
 	($rbytes < 0) and die "read error on firmware file: $!";
 	($rbytes == $len) or die "short read on firmware file ($rbytes < $len)";

 	my $wbytes = $dc->write($buffer, $len, 600);
 	($wbytes < 0) and die "write error on FTP data connection: $!";
 	($rbytes == $wbytes) or die "short write on FTP data connection ($wbytes < $rbytes)";

 	$fwsize -= $len;
 	print STDERR ".";
 }

 $dc->close();
 print STDERR " done.\n";

 #
 # Reboot
 #

 print STDERR "Rebooting device.\n";
 $ftp->reboot();
	#!/usr/bin/env perl
	#
	# D-Link DSL-502T flash utility
	#
	# Copyright (c) 2007 Oliver Jowett <oliver@opencloud.com>
	#
	# Based on adam2flash.pl for the D-Link DSL-G6x4T, which is:
	# Copyright (C) 2005 Felix Fietkau <mailto@nbd.name>
	# based on fbox recovery util by Enrik Berkhan
	#
	# 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
	#

	# The default DSL-502T mtd map looks like this:
	#
	# mtd0 0x90091000,0x903f0000 # filesystem
	# mtd1 0x90010090,0x90091000 # kernel
	# mtd2 0x90000000,0x90010000 # bootloader - DO NOT MODIFY
	# mtd3 0x903f0000,0x90400000 # config space - DO NOT MODIFY
	# mtd4 0x90010000,0x903f0000 # firmware signature + kernel + filesystem, used to flash new firmware
	#
	# i.e. the flash layout is:
	#
	# 90000000-9000FFFF mtd2 bootloader
	# 90010000-9001008F ---- firmware signature )
	# 90010090-90090FFF mtd1 kernel ) mtd4 spans these three regions
	# 90091000-903EFFFF mtd0 filesystem )
	# 903F0000-903FFFFF mtd3 config space
	#
	# The ADAM2 bootloader uses the mtd1 settings to find the start of the image to boot.
	# The image to load contains information about the loadable size of the image. If ADAM2 sees
	# that the image appears to extend beyond the end of mtd1, it will refuse to load it. On
	# the DSL-502T, this manifests as the USB light blinking rapidly on boot.
	#
	# The OpenWRT kernel does not follow quite the same layout:
	# (a) it does not have a 0x90-byte firmware signature prefix
	# (b) it is larger than the default mtd1 size
	#
	# (a) would be avoidable (build a custom image with a 0x90-byte prefix) but (b) is unavoidable.
	# So we have to change mtd1. The simplest thing to do seems to make it span all of
	# the flashable area, producing this layout:
	#
	# mtd0 0x90091000,0x903f0000 # filesystem
	# mtd1 0x90010000,0x903f0000 # kernel (CHANGED)
	# mtd2 0x90000000,0x90010000 # bootloader - DO NOT MODIFY
	# mtd3 0x903f0000,0x90400000 # config space - DO NOT MODIFY
	# mtd4 0x90010000,0x903f0000 # kernel + filesystem, used to flash new firmware
	#
	# * NOTE NOTE NOTE NOTE *
	#
	# /dev/mtd0 .. /dev/mtd4 when using OpenWRT do NOT correspond to the ADAM2 mtd0-4 settings!
	# Instead, OpenWRT scans the MTD itself and determines its own boundaries which are arranged
	# quite differently to ADAM2. It will look something like this, see dmsg on boot:
	#
	# (/dev/mtd0) 0x00000000-0x00010000 : "loader" # Bootloader, read-only
	# (/dev/mtd1) 0x003f0000-0x00400000 : "config" # Config space
	# (/dev/mtd2) 0x00010000-0x003f0000 : "linux" # Firmware area (kernel + root fs + JFFS area)
	# (/dev/mtd3) 0x000d0d58-0x003f0000 : "rootfs" # Root FS, starts immediately after kernel
	# (/dev/mtd4) 0x00280000-0x003f0000 : "rootfs_data" # If rootfs is squashfs, start of JFFS area.
	#
	# All of those boundaries are autodetected by examining the data in flash.
	#
	# * NOTE NOTE NOTE NOTE *

	use IO::Socket::INET;
	use Socket;
	use strict;
	use warnings;

	sub usage() {
	print STDERR "Usage: $0 <ip> [-setmtd1] [-noflash] [firmware.bin]\n\n";
	print STDERR "Acquires the ADAM2 bootloader of a D-Link DSL-504T at <ip>\n";
	print STDERR "Power off the device, start this script, then power it on.\n";
	print STDERR "<ip> may be any spare address on the local subnet.\n\n";
	print STDERR "If a firmware file is specified, MTD settings are verified and\n";
	print STDERR "then the firmware is written to the router's flash.\n";
	print STDERR "The firmware type (D-Link or OpenWRT) is automatically detected.\n\n";
	print STDERR " -setmtd1 update mtd1 if it is not the appropriate value for this firmware\n";
	print STDERR " -noflash does normal checks, updates mtd1 if requested, but does not actually write firmware\n\n";
	exit 0;
	}

	my $ip = shift @ARGV;
	$ip and $ip =~ /\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}/ or usage();

	my $probe = IO::Socket::INET->new(Proto => 'udp',
	Broadcast => 1,
	LocalPort => 5035) or die "socket: $!";
	my $setip = unpack("N", inet_aton($ip));
	$setip > 0 or usage();

	my @packets;
	foreach my $ver ([18, 1], [22, 2]) {
	push @packets, pack("vCCVNV", 0, @$ver, 1, $setip, 0);
	}
	print STDERR "Looking for device: ";
	my $broadcast = sockaddr_in(5035, INADDR_BROADCAST);
	my $scanning;
	my $box;

	$SIG{"ALRM"} = sub {
	return if --$scanning <= 0;
	foreach my $packet (@packets) {
	$probe->send($packet, 0, $broadcast);
	}
	print STDERR ".";
	};

	$scanning = 15;
	foreach my $packet (@packets) {
	$probe->send($packet, 0, $broadcast);
	}
	print STDERR ".";

	while($scanning) {
	my $reply;

	alarm(1);
	if (my $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) {
	$scanning = 0;
	printf STDERR " found!\nADAM2 version $major.$minor1.$minor2 at %s (%s)\n", inet_ntoa($addr), inet_ntoa($addr2);
	$box = inet_ntoa($addr);
	}
	}
	}

	$box or die " not found!\n";

	alarm(0);

	{
	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 _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;
	}
	}

	my $file;
	my $arg;
	my $noflash = 0;
	my $setmtd1 = 0;
	while ($arg = shift @ARGV) {
	if ($arg eq "-noflash") { $noflash = 1; }
	elsif ($arg eq "-setmtd1") { $setmtd1 = 1; }
	else { $file = $arg; }
	}

	if (!$file) {
	print STDERR "No firmware file specified, exiting.\n";
	exit 0;
	}

	#
	# Firmware checks
	#

	open FILE, "<$file" or die "can't open firmware file\n";

	# D-Link firmware starts with "MTD4" little-endian, then has an image header at 0x90
	# OpenWRT firmware just starts with an image header at 0x00

	my $signature;
	my $sbytes = read FILE, $signature, 4;
	($sbytes == 4) or die "can't read firmware signature: $!";

	my $expectedmtd4 = "0x90010000,0x903f0000";
	my $fwtype;
	my $expectedmtd1;

	if ($signature eq "4DTM") {
	seek FILE, 0x90, 0 or die "can't read firmware signature: $!";
	$sbytes = read FILE, $signature, 4;
	($sbytes == 4) or die "can't read firmware signature: $!";
	if ($signature eq "\x42\xfa\xed\xfe") {
	$fwtype = "D-Link (little-endian)";
	$expectedmtd1 = "0x90010090,0x90091000";
	} elsif ($signature eq "\xde\xad\xbe\x42") {
	$fwtype = "D-Link (big-endian)";
	$expectedmtd1 = "0x90010090,0x90091000";
	}
	} elsif ($signature eq "\x42\xfa\xed\xfe") {
	$fwtype = "OpenWRT (little-endian)";
	$expectedmtd1 = "0x90010000,0x903f0000";
	} elsif ($signature eq "\xde\xad\xbe\x42") {
	$fwtype = "OpenWRT (big-endian)";
	$expectedmtd1 = "0x90010000,0x903f0000";
	}

	$fwtype or die "Unknown firmware signature (are you sure that's the right firmware?)";
	print STDERR "Firmware type: $fwtype\n";

	#
	# Bootloader login
	#

	print STDERR "logging into ADAM2 bootloader.. ";
	my $ftp = ADAM2FTP->new($box, Debug => 0, Timeout => 600) or die "can't open control connection\n";
	$ftp->login("adam2", "adam2") or die "can't login\n";
	print STDERR "ok.\n";

	#
	# Hardware checks
	#

	print STDERR "checking hardware.. ";
	my $prd = $ftp->getenv("ProductID");
	my $usb = $ftp->getenv("usb_prod");
	print STDERR "$prd / $usb.\n";
	($prd eq "AR7RD" \|\| $prd eq "AR7DB") or die "doesn't look like a DSL-502T?";
	($usb eq "DSL-502T") or die "doesn't look like a DSL-502T?";

	#
	# MTD checks and update
	#

	print STDERR "checking MTD settings.. ";

	my $mtd4 = $ftp->getenv("mtd4");
	($mtd4 eq $expectedmtd4) or die "MTD4 was not as expected (should be '$expectedmtd4', was '$mtd4'). Cowardly refusing to do anything about it!";

	# check MTD1 setting and update if needed
	my $mtd1 = $ftp->getenv("mtd1");
	if ($mtd1 ne $expectedmtd1) {
	die "MTD1 was not as expected (should be '$expectedmtd1', was '$mtd1'). Run with -setmtd1 to reset mtd1" unless ($setmtd1);
	print STDERR "Setting mtd1.. ";
	($ftp->command("SETENV","mtd1,$expectedmtd1")->response() == Net::FTP::CMD_OK) or die "can't set mtd1";
	$file = shift @ARGV;
	}

	print STDERR "ok.\n";

	#
	# Firmware size check
	#

	my $fwsize = (stat(FILE))[7];
	printf STDERR "Firmware size: 0x%08x\n", $fwsize;
	my $flashsize;
	$mtd4 =~ /^(0x\w+),(0x\w+)$/ and $flashsize = hex($2) - hex($1);
	printf STDERR "Available flash space: 0x%08x\n", $flashsize;
	die "firmware is too large" if ($flashsize < $fwsize);

	#
	# Flash it!
	#

	if ($noflash) {
	print STDERR "Not flashing firmware as -noflash was specified.\n";
	exit 0;
	}

	seek FILE, 0, 0, or die "can't seek in firmware: $!";

	print STDERR "Preparing to flash.. ";
	($ftp->command("MEDIA FLSH")->response() == Net::FTP::CMD_OK) or die "can't set MEDIA FLSH";
	$ftp->binary() or die "can't set binary mode";
	print STDERR "ok.\n";
	print STDERR "Erasing flash and establishing data connection (this may take a while): ";

	my $dc = $ftp->stor("fs mtd4");
	$dc or die "can't open data connection: $!\n";
	print STDERR "ok.\n";

	print STDERR "Writing firmware: ";
	while ($fwsize > 0) {
	my $buffer;
	my $len = ($fwsize > 1024 ? 1024 : $fwsize);

	my $rbytes = read FILE, $buffer, $len;
	($rbytes < 0) and die "read error on firmware file: $!";
	($rbytes == $len) or die "short read on firmware file ($rbytes < $len)";

	my $wbytes = $dc->write($buffer, $len, 600);
	($wbytes < 0) and die "write error on FTP data connection: $!";
	($rbytes == $wbytes) or die "short write on FTP data connection ($wbytes < $rbytes)";

	$fwsize -= $len;
	print STDERR ".";
	}

	$dc->close();
	print STDERR " done.\n";

	#
	# Reboot
	#

	print STDERR "Rebooting device.\n";
	$ftp->reboot();