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#!/usr/bin/perl |
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|
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# (c)2003 Marc Alexander Lehmann <nbd@plan9.de> |
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# |
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# This file is released under the General Public License, version 2 or later. |
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|
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require v5.8; |
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|
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use strict 'subs'; |
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|
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use Socket; |
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use IO::Socket::INET; |
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|
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$VERSION = 0.1; |
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|
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############################################################################# |
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|
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$DEV = "/dev/nd0"; |
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|
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umask 077; |
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|
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for (0..7) { |
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-e "/dev/nd$_" || qx<sh -x -c "mknod /dev/nd$_ b 43 $_">; |
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} |
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|
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print <<EOF; |
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|
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WARNING: This program contains a locally exploitable race condition. |
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EOF |
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|
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sub NBD_SET_SOCK (){ 0x0000ab00 } |
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sub NBD_SET_BLKSIZE (){ 0x0000ab01 } |
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sub NBD_SET_SIZE (){ 0x0000ab02 } |
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sub NBD_DO_IT (){ 0x0000ab03 } |
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sub NBD_CLEAR_SOCK (){ 0x0000ab04 } |
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sub NBD_CLEAR_QUE (){ 0x0000ab05 } |
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sub NBD_PRINT_DEBUG (){ 0x0000ab06 } |
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sub NBD_SET_SIZE_BLOCKS (){ 0x0000ab07 } |
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sub NBD_DISCONNECT (){ 0x0000ab08 } |
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|
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open ND, "+<", $DEV or die "$DEV: $!"; |
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|
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ioctl ND, NBD_CLEAR_QUE, my $x or die "NBD_CLEAR_QUE: $!"; |
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ioctl ND, NBD_DISCONNECT, my $x; |
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ioctl ND, NBD_CLEAR_SOCK, my $x; |
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|
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############################################################################# |
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|
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$BIN = shift or die "usage: $0 iso9660.bin"; |
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|
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open BIN, "<", $BIN or die "$BIN: $!"; |
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|
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# create a socketpair... ugh |
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my $srv = new IO::Socket::INET LocalHost => "127.0.0.1", Listen => 1 |
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or die "unable to create listen socket: $!"; |
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my $cli = new IO::Socket::INET PeerHost => $srv->sockhost, PeerPort => $srv->sockport |
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or die "unable to connect to listen socket: $!"; |
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$srv = $srv->accept |
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or die "accept: $!"; |
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|
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# TODO: should exchange secure token, but I don't care for races now |
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|
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ioctl ND, NBD_SET_SOCK, 0 + fileno $cli or die "NBD_SET_SOCK: $!"; |
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|
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sub REQ_MAGIC () { 0x25609513 } |
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sub REQ($) { unpack "N N a8 NN N", $_[0] } |
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sub REQ_SIZE (){ 4+4+4 + 8 + 8 } |
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sub REP_MAGIC () { 0x67446698 } |
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sub REP($$$;$) { pack "N N a8 a*", @_ } |
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|
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if (!($srv_pid = fork)) { |
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ioctl ND, NBD_DO_IT, my $x |
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or die "unable do _do_ _it_: $!"; |
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exit; |
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} |
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|
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$SIG{INT} = |
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$SIG{TERM} = |
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$SIG{QUIT} = |
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$SIG{HUP} = sub { exit }; |
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|
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sub END { |
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if ($srv_pid) { |
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print "killing server...\n"; |
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kill 9, $srv_pid; |
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} |
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print "bye.\n"; |
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} |
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|
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#if (fork == 0) { |
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# system "isoinfo", "-l", "-i", $DEV; |
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# _exit(1); |
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#} |
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|
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print <<EOF; |
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|
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Everything seems to be set up now, try sth. like: |
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|
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mount -tiso9660 $DEV /mnt |
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|
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Press ^C to exit... |
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EOF |
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|
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while (REQ_SIZE == sysread $srv, my $req, REQ_SIZE) { |
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my ($magic, $type, $handle, undef, $from, $len) = REQ $req; |
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|
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$magic == REQ_MAGIC |
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or die "protocol error (magic number mismatch)"; |
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|
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my ($from_l, $from_h) = ($from & 2047, $from >> 11); |
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|
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if ($type == 0) { |
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printf "READ %08x \@%08x (block $from_h+$from_l)\n", $len, $from; |
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|
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syswrite $srv, REP REP_MAGIC, 0, $handle; |
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|
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while ($len) { |
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sysseek BIN, ($from_h * 2352) + $from_l + 0x18, 0 |
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or die; |
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|
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$from_l = 2048 - $from_l; |
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$from_l < $len or $from_l = $len; |
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|
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sysread BIN, my $buf, $from_l; |
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|
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$from_l == length $buf or $buf = "\x0" x $from_l; |
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|
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syswrite $srv, $buf; |
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|
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$len -= $from_l; |
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|
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$from_l = 0; |
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$from_h++; |
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} |
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} elsif ($type == 1) { |
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die "write not supported\n"; |
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} elsif ($type == 2) { |
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print "disconnect requested, exiting...\n"; |
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last; |
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} else { |
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die "unsupported operation ($type)\n"; |
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} |
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} |
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|
