mkjail.pl 33.3 KB
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#!/usr/bin/perl -w
#
# EMULAB-COPYRIGHT
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# Copyright (c) 2000-2004 University of Utah and the Flux Group.
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# All rights reserved.
#
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# Kernel, jail, netstat, route, ifconfig, ipfw, header files.
# 
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use English;
use Getopt::Std;
use Fcntl;
use IO::Handle;
use Socket;
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use Fcntl ':flock';
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# Drag in path stuff so we can find emulab stuff. Also untaints path.
BEGIN { require "/etc/emulab/paths.pm"; import emulabpaths; }

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use libsetup qw(REMOTE LOCALROOTFS TMTOPOMAP TBDebugTimeStamp);
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use libtmcc;
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#
# Questions:
#
# * Whats the hostname for the jail? Perhaps vnodename.emulab.net
# * What should /etc/resolv.conf look like?
# 

#
# Create a jailed environment. There are some stub files stored in
# /etc/jail that copied into the jail.
#
sub usage()
{
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    print("Usage: mkjail.pl [-V] [-s] [-i <ipaddr>] [-p <pid>] ".
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	  "[-h <hostname>] <vnodeid>\n");
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    exit(-1);
}
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my  $optlist = "Vi:p:e:sh:";
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#
# Only real root can run this script.
#
if ($UID) {
    die("Must be root to run this script!\n");
}
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system("sysctl jail.set_hostname_allowed=0 >/dev/null 2>&1");
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#
# Catch ^C and exit with error. 
#
my $leaveme = 0;
sub handler ($) {
    my ($signame) = @_;
    
    $SIG{INT}  = 'IGNORE';
    $SIG{USR1} = 'IGNORE';
    $SIG{TERM} = 'IGNORE';
    $SIG{HUP}  = 'IGNORE';

    if ($signame eq 'USR1') {
	$leaveme = 1;
    }
    fatal("Caught a SIG${signame}! Killing the jail ...");
}
$SIG{INT}  = \&handler;
$SIG{USR1} = \&handler;
$SIG{HUP}  = \&handler;
$SIG{TERM} = 'IGNORE';

#
# Turn off line buffering on output
#
STDOUT->autoflush(1);
STDERR->autoflush(1);

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# XXX
my $JAILCNET	   = "172.16.0.0";
my $JAILCNETMASK   = "255.240.0.0";

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#
# XXX hack: use loopback NFS mounts rather than nullfs loopback mounts
# which are still buggy.  Can do either for one or both of local
# filesystems (ROOTMNTDIRS) or remote filesystems (/proj, /users).
#
my $NFSMOUNT_LOCAL  = 1;
my $NFSMOUNT_REMOTE = 0;	# too much load on NFS server

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#
# Locals
#
my $JAILPATH	= "/var/emulab/jails";
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my $ETCJAIL     = "/etc/jail";
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my $DEVCACHEMEM = "$JAILPATH/devmem";
my $DEVCACHENMEM= "$JAILPATH/devnomem";
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my $LOCALFS	= LOCALROOTFS();
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my $LOCALMNTPNT = "/local";
my $TMCC	= "$BINDIR/tmcc";
my $JAILCONFIG  = "jailconfig";
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my @ROOTCPDIRS	= ("etc", "root");
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my @ROOTMKDIRS  = ("dev", "tmp", "var", "usr", "proc", "users", 
		   "bin", "sbin", "home", $LOCALMNTPNT);
my @ROOTMNTDIRS = ("bin", "sbin", "usr");
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my @EMUVARDIRS	= ("logs", "db", "jails", "boot", "lock");
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my $VNFILESECT  = 512 * ((1024 * 1024) / 512); # 64MB in 512b sectors.
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my $MAXVNDEVS	= 100;
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my $IP;
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my $IPALIAS;
my $IPMASK;
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my $PID;
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my $idnumber;
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my $jailhostname;
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my $debug	= 1;
my $cleaning	= 0;
my $vndevice;
my @mntpoints   = ();
my $jailpid;
my $tmccpid;
my $interactive = 0;
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my $USEVCNETROUTES = 0;
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my @controlroutes = ();
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# This stuff is passed from tmcd, which we parse into a config string
# and an option set.
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my %jailconfig  = ();
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my $jailoptions = "";
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my $sshdport    = 50000;	# Bogus default, good for testing.
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my $routetabid;			# Default to main routing table.
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my $jailflags   = 0;
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my @jailips     = ();		# List of jail IPs (for routing table).
my $JAIL_DEVMEM = 0x01;		# We need to know if these options given.
my $JAIL_ROUTING= 0x02;
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#
# Parse command arguments. Once we return from getopts, all that should be
# left are the required arguments.
#
%options = ();
if (! getopts($optlist, \%options)) {
    usage();
}
if (@ARGV != 1) {
    usage();
}
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my $vnodeid = $ARGV[0];
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#
# Untaint the arguments.
#
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if ($vnodeid =~ /^([-\w\/\.]+)$/) {
    $vnodeid = $1;
    $jailhostname = $1;
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}
else {
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    die("Tainted argument $vnodeid!\n");
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}

if (defined($options{'s'})) {
    $interactive = 1;
}

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if (defined($options{'V'})) {
    $USEVCNETROUTES = 1;
}

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#
# If the vnodeid looks like what we expect (pcvmXXX-YYY) then pull out
# the YYY part and use that for the rtabid and the vn device number.
# Saves on searching and allocation. Need a better solution at some point.
#
if ($vnodeid =~ /^[\w]*-(\d+)$/) {
    $idnumber = $1;
}

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TBDebugTimeStamp("mkjail starting to do real work");

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#
# Get the parent IP.
# 
my $hostname = `hostname`;
my $hostip;

# Untaint and strip newline.
if ($hostname =~ /^([-\w\.]+)$/) {
    $hostname = $1;

    my (undef,undef,undef,undef,@ipaddrs) = gethostbyname($hostname);
    $hostip = inet_ntoa($ipaddrs[0]);
}

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#
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# If no IP, then it defaults to our hostname's IP, *if* none is provided
# by the jail configuration file. That check is later. 
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# 
if (defined($options{'i'})) {
    $IP = $options{'i'};

    if ($IP =~ /^(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})$/) {
	$IP = $1;
    }
    else {
	die("Tainted argument $IP!\n");
    }
}

if (defined($options{'p'})) {
    $PID = $options{'p'};

    if ($PID =~ /^([-\@\w]+)$/) {
	$PID = $1;
    }
    else {
	die("Tainted argument $PID.");
    }
}

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if (defined($options{'h'})) {
    $jailhostname = $options{'h'};

    if ($jailhostname =~ /^([-\w\.]+)$/) {
	$jailhostname = $1;
    }
    else {
	die("Tainted argument $jailhostname.");
    }
}

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#
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# In most cases, the $vnodeid directory will have been created by the caller,
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# and a config file possibly dropped in.
# When debugging, we have to create it here. 
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# 
chdir($JAILPATH) or
    die("Could not chdir to $JAILPATH: $!\n");

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if (! -e $vnodeid) {
    mkdir($vnodeid, 0770) or
	fatal("Could not mkdir $vnodeid in $JAILPATH: $!");
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}
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else {
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    TBDebugTimeStamp("mkjail getting jail config");
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    getjailconfig("$JAILPATH/$vnodeid");
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}

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my $phys_cnet_if = `control_interface`;
chomp($phys_cnet_if);

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#
# See if special options supported, and if so setup args as directed.
#
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TBDebugTimeStamp("mkjail setting jail options");
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setjailoptions();
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#
# If no IP set in the jail config, then use hostip.
#
if (!defined($IP)) {
    $IP = $hostip;
}

print("Setting up jail for $vnodeid using $IP\n")
    if ($debug);

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#
# Create the "disk";
#
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if (-e "$vnodeid/root") {
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    #
    # Try to pick up where we left off.
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    #
    TBDebugTimeStamp("mkjail restoring root fs");
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    restorerootfs("$JAILPATH/$vnodeid");
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}
else {
    #
    # Create the root filesystem.
    #
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    TBDebugTimeStamp("mkjail creating root fs");
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    mkrootfs("$JAILPATH/$vnodeid");
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}
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TBDebugTimeStamp("mkjail done with root fs");
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#
# Lets tell the caller it can proceed. 
#
system("touch $JAILPATH/$vnodeid/proceed");

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#
# If the jail has its own IP, must insert the control network alias.
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# We use a 255.255.255.255 netmask since there might be multiple
# virtual nodes from the same subnet on this node. 
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#
if (defined($IPALIAS)) {
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    setcnethostalias($IPALIAS);
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}

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#
# Add control routes if jail gets its own route table.
#
if ($jailflags & $JAIL_ROUTING) {
    addcontrolroutes();
}

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#
# Set up jail interfaces. We pass it the rtabid as well, and the script
# does all the right stuff. 
#
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TBDebugTimeStamp("mkjail doing ifsetup for jail");
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mysystem("ifsetup -j $vnodeid ".
	 (($jailflags & $JAIL_ROUTING) ? "-r $routetabid " : "") .
	 "boot");
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#
# Start the tmcc proxy. This path will be valid in both the outer
# environment and in the jail!
#
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TBDebugTimeStamp("mkjail starting the tmcc proxy");
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startproxy("$JAILPATH/$vnodeid");
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TBDebugTimeStamp("mkjail tmcc proxy is running");
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#
# Start the jail. We do it in a child so we can send a signal to the
# jailed process to force it to shutdown. The jail has to shut itself
# down.
#
$jailpid = fork();
if ($jailpid) {
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    #
    # We do not really care about the exit status of the jail. We want to catch
    # any children, which includes the tmcc proxy. If it dies, something has
    # gone wrong, and that appears to happen a lot. Lets restart it until we
    # figure out what is going wrong.
    #
    while (1) {
	my $kidpid = waitpid(-1, 0);

	if ($kidpid == $jailpid) {
	    undef($jailpid);
	    last;
	}
	if ($kidpid == $tmccpid) {
	    print("TMCC proxy exited with status $?. Restarting ...\n");
	    startproxy("$JAILPATH/$vnodeid");
	    next;
	}
	print("Unknown child $kidpid exited with status $?!\n");
    }
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}
else {
    $SIG{TERM} = 'DEFAULT';
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    $ENV{'TMCCVNODEID'} = $vnodeid;
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    TBDebugTimeStamp("mkjail starting the jail");
    
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    my $cmd = "jail $jailoptions $JAILPATH/$vnodeid/root $jailhostname $IP ".
	"/etc/jail/injail -v $vnodeid";
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    if ($interactive) {
	$cmd .= " /bin/csh";
    }
    exec($cmd);
    die("*** $0:\n".
	"    exec failed to start the jail!\n");
}
	 
#
# Once we exit, cleanup the mess.
#
cleanup();
exit(0);

#
# Create a file for a vnode device, vnconfig it, newfs, and then
# mount it on the "root" directory.
#
sub mkrootfs($)
{
    my ($path) = @_;
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    my $vnsize = $VNFILESECT;
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    chdir($path) or
	fatal("Could not chdir to $path: $!");

    mkdir("root", 0770) or
	fatal("Could not mkdir 'root' in $path: $!");
    
    #
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    # Lots of zeros. Note we oseek to create a big hole.
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    #
    TBDebugTimeStamp("mkjail doing the dd");
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    mysystem("dd if=/dev/zero of=root.vnode bs=512 oseek=$vnsize count=1");
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    TBDebugTimeStamp("mkjail done with the dd");
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    #
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    # Find a free vndevice. We start with the obvious choice, and if that
    # fails, fall back to searching.
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    #
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    if (defined($idnumber) && CheckFreeVN($idnumber, "root.vnode")) {
	$vndevice = $idnumber;
    }
    else {
	for (my $i = 0; $i < $MAXVNDEVS; $i++) {
	    if (CheckFreeVN($i, "root.vnode")) {
		$vndevice = $i;
		last;
	    }
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	}
    }
    fatal("Could not find a free vn device!") 
	if (!defined($vndevice));
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    print("Using vn${vndevice}\n")
 	if ($debug);
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    TBDebugTimeStamp("mkjail vnconfig, label, newfs, tunefs, mount");
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    mysystem("vnconfig -s labels vn${vndevice} root.vnode");
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    mysystem("disklabel -r -w vn${vndevice} auto");
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    mysystem("newfs -U -b 8192 -f 1024 -i 16384 -c 15 /dev/vn${vndevice}c");
    mysystem("tunefs -m 5 -o time /dev/vn${vndevice}c");
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    mysystem("mount /dev/vn${vndevice}c root");
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    TBDebugTimeStamp("mkjail vnconfig, label, newfs, tunefs, mount done!");
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    push(@mntpoints, "$path/root");

    #
    # Okay, copy in the top level directories. 
    #
    foreach my $dir (@ROOTCPDIRS) {
	mysystem("hier -f -FN cp /$dir root/$dir");
    }
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    TBDebugTimeStamp("mkjail copying root cp dirs done!");
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    #
    # Make some other directories that are nice to have!
    #
    foreach my $dir (@ROOTMKDIRS) {
	mkdir("root/$dir", 0755) or
	    fatal("Could not mkdir '$dir' in $path/root: $!");
    }
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    TBDebugTimeStamp("mkjail creating root mkdir dirs done!");
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    #
    # Okay, mount some other directories to save space.
    #
    foreach my $dir (@ROOTMNTDIRS) {
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	if ($NFSMOUNT_LOCAL) {
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	    mysystem("mount -r localhost:/$dir $path/root/$dir");
	} else {
	    mysystem("mount -r -t null /$dir $path/root/$dir");
	}
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	push(@mntpoints, "$path/root/$dir");
    }
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    TBDebugTimeStamp("mkjail mounting root NFS dirs done!");
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    #
    # The proc FS in the jail is per-jail of course.
    # 
    mysystem("mount -t procfs proc $path/root/proc");
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    TBDebugTimeStamp("mkjail mounting /proc done!");
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    push(@mntpoints, "$path/root/proc");

    #
    # /tmp is special of course
    #
    mysystem("chmod 1777 root/tmp");

    #
    # /dev is also special. It gets a very restricted set of entries.
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    # Note that we create some BPF devices since they work in our jails.
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    #
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    # Set up the dev directory cache; running MAKEDEV is incredibly slow,
    # but copying a directory device entries is really fast!
    #
    if (! -e $DEVCACHEMEM) {
	TBDebugTimeStamp("mkjail creating /dev cached copy");
	
	mkdir($DEVCACHEMEM, 0755) or
	    fatal("Could not mkdir $DEVCACHEMEM: $!");
	mkdir($DEVCACHENMEM, 0755) or
	    fatal("Could not mkdir $DEVCACHENMEM: $!");

	# Jails with JAIL_DEVMEM get more devices.
	mysystem("cd $DEVCACHEMEM; cp -p /dev/MAKEDEV .; ".
		 " ./MAKEDEV bpf31 std pty0; " .
		 # Remove some extraneous devices.
		 "rm -f pci io klog console; " .
		 #
		 # "Link" /dev/console to /dev/null We actually create a
		 # separate special file rather than just linking in case
		 # anyone mucks with the permissions on /dev/console.
		 #
		 "hier cp null console; chmod 600 console");

	# Otherwise no devmem.
	mysystem("cd $DEVCACHENMEM; cp -p /dev/MAKEDEV .; ".
		 " ./MAKEDEV bpf31 jail; " .
		 # Remove some extraneous devices.
		 "rm -f pci io klog console; " .
		 #
		 # "Link" /dev/console to /dev/null We actually create a
		 # separate special file rather than just linking in case
		 # anyone mucks with the permissions on /dev/console.
		 #
		 "hier cp null console; chmod 600 console");
    }

    #
    # Now copy contents of cached device directory.
    # 
    TBDebugTimeStamp("mkjail copying cached /dev directory");
    
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    if ($jailflags & $JAIL_DEVMEM) {
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	mysystem("hier cp $DEVCACHEMEM $path/root/dev");
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    }
    else {
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	mysystem("hier cp $DEVCACHENMEM $path/root/dev");
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    }
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    #
    # Create stub /var and create the necessary log files.
    #
    # NOTE: I stole this little diddy from /etc/rc.diskless2.
    #
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    TBDebugTimeStamp("mkjail creating /var");
    
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    mysystem("mtree -nqdeU -f /etc/mtree/BSD.var.dist ".
	     "-p $path/root/var >/dev/null 2>&1");
    mysystem("mkdir -p $path/root/$path");

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    #
    # Make the emulab directories since they are not in the mtree file.
    #
    if (! -e "$path/root/var/emulab") {
	mkdir("$path/root/var/emulab", 0755) or
	    fatal("Could not mkdir 'emulab' in $path/root/var: $!");
    }
    foreach my $dir (@EMUVARDIRS) {
	if (! -e "$path/root/var/emulab/$dir") {
	    mkdir("$path/root/var/emulab/$dir", 0755) or
		fatal("Could not mkdir 'dir' in $path/root/var/emulab: $!");
	}
    }
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    TBDebugTimeStamp("mkjail copying the tmcc cache");
    
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    tmcccopycache($vnodeid, "$path/root");
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    if (-e TMTOPOMAP()) {
	mysystem("cp -fp " . TMTOPOMAP() . " $path/root/var/emulab/boot");
    }
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    #
    # Stash the control net IP if not the same as the host IP
    #
    if ($IP ne $hostip) {
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	mysystem("echo $IP > $path/root/var/emulab/boot/myip");
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    }

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    TBDebugTimeStamp("mkjail creating /var/log files");

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    #
    # Get a list of all the plain files and create zero length versions
    # in the new var.
    #
    opendir(DIR, "/var/log") or
	fatal("Cannot opendir /var/log: $!");
    my @logs = grep { -f "/var/log/$_" } readdir(DIR);
    closedir(DIR);

    foreach my $log (@logs) {
	mysystem("touch $path/root/var/log/$log");
    }

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    TBDebugTimeStamp("mkjail configuring etc files");

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    #
    # Now a bunch of stuff to set up a nice environment in the jail.
    #
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    mysystem("cp -p $ETCJAIL/rc.conf $path/root/etc");
    mysystem("rm -f $path/root/etc/rc.conf.local");
    mysystem("cp -p $ETCJAIL/rc.local $path/root/etc");
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    mysystem("cp -p $ETCJAIL/crontab $path/root/etc");
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    mysystem("cp /dev/null $path/root/etc/fstab");
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    mysystem("ln -s /usr/compat $path/root/compat");
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    # No X11 forwarding. 
    mysystem("cat $path/root/etc/ssh/sshd_config | ".
	     "sed -e 's/^X11Forwarding.*yes/X11Forwarding no/' > ".
	     "$path/root/tmp/sshd_foo");
    mysystem("cp -f $path/root/tmp/sshd_foo $path/root/etc/ssh/sshd_config");
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    # Port/Address for sshd.
    if ($IP ne $hostip) {
	mysystem("echo 'ListenAddress $IP' >> ".
		 "$path/root/etc/ssh/sshd_config");
    }
    else {
	mysystem("echo 'sshd_flags=\"\$sshd_flags -p $sshdport\"' >> ".
		 "$path/root/etc/rc.conf");
    }
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    # In the jail, 127.0.0.1 refers to the jail, but we want to use the
    # nameserver running *outside* the jail.
    mysystem("cat /etc/resolv.conf | ".
	     "sed -e 's/127\.0\.0\.1/$hostip/' > ".
	     "$path/root/etc/resolv.conf");
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    TBDebugTimeStamp("mkjail setting up password/group files");

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    #
    # Password/group file stuff. If remote the jail picks them up. Locally
    # we start with current set of accounts on the physnode, since this is
    # more efficient (less tmcd work), and besides, the physnode starts with
    # exactly the same accounts.
    #
    if (REMOTE()) {
	mysystem("cp -p $ETCJAIL/group $path/root/etc");
	mysystem("cp -p $ETCJAIL/master.passwd $path/root/etc");
	mysystem("pwd_mkdb -p -d $path/root/etc $path/root/etc/master.passwd");
    }
    else {
	mysystem("cp -p /etc/group $path/root/etc");
	mysystem("cp -p /etc/master.passwd $path/root/etc");
	mysystem("pwd_mkdb -p -d $path/root/etc $path/root/etc/master.passwd");
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	# XXX
	mysystem("cp -p $DBDIR/passdb.db $path/root/$DBDIR");
	mysystem("cp -p $DBDIR/groupdb.db $path/root/$DBDIR");
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    }
    
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    TBDebugTimeStamp("mkjail mounting NFS filesystems");
    
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    #
    # Give the jail an NFS mount of the local project directory. This one
    # is read-write.
    #
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    if (defined($PID) && -e $LOCALFS && -e "$LOCALFS/$PID") {
	mysystem("mkdir -p $path/root/$LOCALMNTPNT/$PID");
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	if ($NFSMOUNT_REMOTE) {
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	    mysystem("mount localhost:$LOCALFS/$PID ".
		     "      $path/root/$LOCALMNTPNT/$PID");
	} else {
	    mysystem("mount -t null $LOCALFS/$PID ".
		     "      $path/root/$LOCALMNTPNT/$PID");
	}
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	push(@mntpoints, "$path/root/$LOCALMNTPNT/$PID");
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#	mysystem("ln -s $LOCALMNTPNT/$PID/$vnodeid $path/root/opt");
	mkdir("$path/root/opt", 0775);
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    }
    else {
	mkdir("$path/root/opt", 0775);
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    }

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    #
    # Ug. Until we have SFS working the way I want it, NFS mount the
    # usual directories inside the jail. This duplicates a lot of mounts,
    # but not sure what to do about that. 
    #
    if (! REMOTE()) {
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	mysystem("$BINDIR/rc/rc.mounts ".
		 "-j $vnodeid $path/root $NFSMOUNT_REMOTE boot");
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    }
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    TBDebugTimeStamp("mkjail mounting NFS filesystems done");
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    cleanmess($path);
    return 0;
}

#
# Restore a jail after a crash.
#
sub restorerootfs($)
{
    my ($path) = @_;

    chdir($path) or
	fatal("Could not chdir to $path: $!");

    #
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    # Find a free vndevice. We start with the obvious choice, and if that
    # fails, fall back to searching.
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    #
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    if (defined($idnumber) && CheckFreeVN($idnumber, "root.vnode")) {
	$vndevice = $idnumber;
    }
    else {
	for (my $i = 0; $i < $MAXVNDEVS; $i++) {
	    if (CheckFreeVN($i, "root.vnode")) {
		$vndevice = $i;
		last;
	    }
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	}
    }
    fatal("Could not find a free vn device!") 
	if (!defined($vndevice));
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    print("Using vn${vndevice}\n")
 	if ($debug);
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    mysystem("vnconfig -s labels vn${vndevice} root.vnode");
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    mysystem("fsck -p -y /dev/vn${vndevice}c");
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    mysystem("mount /dev/vn${vndevice}c root");
    push(@mntpoints, "$path/root");

    #
    # Okay, mount some other directories to save space.
    #
    foreach my $dir (@ROOTMNTDIRS) {
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	if ($NFSMOUNT_LOCAL) {
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	    mysystem("mount -r localhost:/$dir $path/root/$dir");
	} else {
	    mysystem("mount -r -t null /$dir $path/root/$dir");
	}
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	push(@mntpoints, "$path/root/$dir");
    }
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    tmcccopycache($vnodeid, "$path/root");
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    if (-e TMTOPOMAP()) {
	mysystem("cp -fp " . TMTOPOMAP() . " $path/root/var/emulab/boot");
    }
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    #
    # The proc FS in the jail is per-jail of course.
    # 
    mysystem("mount -t procfs proc $path/root/proc");
    push(@mntpoints, "$path/root/proc");

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    #
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    # Stash the control net IP if not the same as the host IP
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    #
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    if ($IP ne $hostip) {
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	mysystem("echo $IP > $path/root/var/emulab/boot/myip");
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    }

    # No X11 forwarding. 
    mysystem("cat $path/root/etc/ssh/sshd_config | ".
	     "sed -e 's/^X11Forwarding.*yes/X11Forwarding no/' > ".
	     "$path/root/tmp/sshd_foo");
    mysystem("cp -f $path/root/tmp/sshd_foo $path/root/etc/ssh/sshd_config");
    
    # Port/Address for sshd.
    if ($IP ne $hostip) {
	mysystem("echo 'ListenAddress $IP' >> ".
		 "$path/root/etc/ssh/sshd_config");
    }
    else {
	mysystem("echo 'sshd_flags=\"\$sshd_flags -p $sshdport\"' >> ".
		 "$path/root/etc/rc.conf");
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    }

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    #
    # Give the jail an NFS mount of the local project directory. This one
    # is read-write.
    #
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    if (defined($PID) && -e $LOCALFS && -e "$LOCALFS/$PID") {
	mysystem("mkdir -p $path/root/$LOCALMNTPNT/$PID");
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	if ($NFSMOUNT_REMOTE) {
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	    mysystem("mount localhost:$LOCALFS/$PID ".
		     "      $path/root/$LOCALMNTPNT/$PID");
	} else {
	    mysystem("mount -t null $LOCALFS/$PID ".
		     "      $path/root/$LOCALMNTPNT/$PID");
	}
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	push(@mntpoints, "$path/root/$LOCALMNTPNT/$PID");
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    }
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    #
    # Ug. Until we have SFS working the way I want it, NFS mount the
    # usual directories inside the jail. This duplicates a lot of mounts,
    # but not sure what to do about that. 
    #
    if (! REMOTE()) {
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	mysystem("$BINDIR/rc/rc.mounts ".
		 "-j $vnodeid $path/root $NFSMOUNT_REMOTE boot");
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    }
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    return 0;
}

#
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# Okay, we clean up some of what is in /etc and /etc/emulab so that the
# jail cannot see that stuff. 
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#
sub cleanmess($) {
    my ($path) = @_;

    #
    # And, some security stuff. We want to remove bits of stuff from the
    # jail that would enable it to talk to tmcd directly. 
    #
    mysystem("rm -f $path/root/etc/emulab.cdkey");
    mysystem("rm -f $path/root/etc/emulab.pkey");

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    # This is /etc/emulab inside the jail.
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    mysystem("rm -f  $path/root/$ETCDIR/*.pem");
    mysystem("rm -f  $path/root/$ETCDIR/cvsup.auth");
    mysystem("rm -rf $path/root/$ETCDIR/.cvsup");
    mysystem("rm -f  $path/root/$ETCDIR/master.passwd");
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    #
    # Copy in emulabman if it exists.
    #
    if (my (undef,undef,undef,undef,undef,undef,undef,$dir) =
	getpwnam("emulabman")) {
	mysystem("hier cp $dir $path/root/home/emulabman");
    }
}

#
# Start the tmcc proxy and insert the unix path into the environment
# for the jail to pick up.
#
sub startproxy($)
{
    my ($dir) = @_;
    my $log   = "$dir/tmcc.log";

    #
    # The point of these paths is so that there is a comman path to
    # the socket both outside and inside the jail. Yuck!
    #
    my $insidepath  = "$dir/tmcc";
    my $outsidepath = "$dir/root/$insidepath";

    $tmccpid = fork();
    if ($tmccpid) {
	#
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	# Create a proxypath file so that libtmcc in the jail will know to
	# use a proxy for all calls; saves having all clients explicitly
	# use -l for every tmcc call.
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	#
	mysystem("echo $insidepath > $dir/root/${BOOTDIR}/proxypath");
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	select(undef, undef, undef, 0.2);
	return 0;
    }
    $SIG{TERM} = 'DEFAULT';

    # The -o option will cause the proxy to detach but not fork!
    # Eventually change this to standard pid file kill.
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    exec("$TMCC -d -x $outsidepath -n $vnodeid -o $log");
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    die("Exec of $TMCC failed! $!\n");
}

#
# Cleanup at exit.
#
sub cleanup()
{
    if ($cleaning) {
	die("*** $0:\n".
	    "    Oops, already cleaning!\n");
    }
    $cleaning = 1;
    
    #
    # Note that the unmounts will fail unless all the processes inside
    # the jail exit!
    # 
    if (defined($tmccpid)) {
	kill('TERM', $tmccpid);
	waitpid($tmccpid, 0);
    }

    if (defined($jailpid)) {
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	kill('USR1', $jailpid);
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	waitpid($jailpid, 0);
    }

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    # Clean up interfaces we might have setup
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    system("ifsetup -j $vnodeid shutdown");
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    # If the jail has its own IP, clean the alias.
    if (defined($IPALIAS)) {
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	clearcnethostalias($IPALIAS);
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    }

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    # Clean control routes
    foreach my $route (reverse(@controlroutes)) {
	print("deleting route: '$route'\n");
	system("route delete -rtabid $routetabid $route");
    }

    # Unmounts.
    if (!REMOTE()) {
	# If this fails, fail, we do want to continue. Dangerous!
	system("$BINDIR/rc/rc.mounts ".
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	       "-j $vnodeid foo $NFSMOUNT_REMOTE shutdown");
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	if ($?) {
	    # Avoid recursive calls to cleanup; do not use fatal.
	    die("*** $0:\n".
		"    rc.mounts failed!\n");
	}
    }

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    while (@mntpoints) {
	my $mntpoint = pop(@mntpoints);

	# If the umounts fail, we do want to continue. Dangerous!
	system("umount $mntpoint");
	if ($?) {
	    # Avoid recursive calls to cleanup; do not use fatal.
	    die("*** $0:\n".
		"    umount '$mntpoint' failed: $!\n");
	}
    }
    if (defined($vndevice)) {
	system("vnconfig -u vn${vndevice}");
    }
    if (!$leaveme) {
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        #
        # Ug, with NFS mounts inside the jail, we need to be really careful.
        #
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	if (-d "$JAILPATH/$vnodeid/root" &&
	    !rmdir("$JAILPATH/$vnodeid/root")) {
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	    die("*** $0:\n".
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		"    $JAILPATH/$vnodeid/root is not empty! This is bad!\n");
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	}
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	system("rm -rf $JAILPATH/$vnodeid");
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    }
}

#
# Print error and exit.
#
sub fatal($)
{
    my ($msg) = @_;

    cleanup();
    die("*** $0:\n".
	"    $msg\n");
}

#
# Run a command string, redirecting output to a logfile.
#
sub mysystem($)
{
    my ($command) = @_;

    system($command);
    if ($?) {
	fatal("Command failed: $? - $command");
    }
}
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#
# Read in the jail config file. 
#
sub getjailconfig($)
{
    my ($path) = @_;

    $path .= "/$JAILCONFIG";

    if (! -e $path) {
	return 0;
    }
    
    if (! open(CONFIG, $path)) {
	print("$path could not be opened for reading: $!\n");
	return -1;
    }
    while (<CONFIG>) {
	if ($_ =~ /^(.*)="(.+)"$/ ||
	    $_ =~ /^(.*)=(.+)$/) {
	    $jailconfig{$1} = $2;
	}
    }
    close(CONFIG);
    return 0;
}

#
# See if special jail opts supported.
#
sub setjailoptions() {
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    my $portrange;
    
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    #
    # Do this all the time, so that we can figure out the sshd port.
    # 
    foreach my $key (keys(%jailconfig)) {
	my $val = $jailconfig{$key};

        SWITCH: for ($key) {
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	    /^JAILIP$/ && do {
		if ($val =~ /([\d\.]+),([\d\.]+)/) {
		    # Set the jail IP, but do not override one on the 
		    # command line.
		    if (!defined($IP)) {
			$IP      = $1;
			$IPALIAS = $1;
			$IPMASK  = $2;
		    }
		}
		last SWITCH;
	    };
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	    /^PORTRANGE$/ && do {
		if ($val =~ /(\d+),(\d+)/) {
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		    $portrange = "$1:$2";
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		}
		last SWITCH;
	    };
	    /^SSHDPORT$/ && do {
		if ($val =~ /(\d+)/) {
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		    $sshdport     = $1;
		}
		last SWITCH;
	    };
	    /^SYSVIPC$/ && do {
		if ($val) {
		    $jailoptions .= " -o sysvipc";
		}
		else {
		    $jailoptions .= " -o nosysvipc";
		}
		last SWITCH;
	    };
	    /^INETRAW$/ && do {
		if ($val) {
		    $jailoptions .= " -o inetraw";
		}
		else {
		    $jailoptions .= " -o noinetraw";
		}
		last SWITCH;
	    };
	    /^BPFRO$/ && do {
		if ($val) {
		    $jailoptions .= " -o bpfro";
		}
		else {
		    $jailoptions .= " -o nobpfro";
		}
		last SWITCH;
	    };
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	    /^INADDRANY$/ && do {
		if ($val) {
		    $jailoptions .= " -o inaddrany";
		}
		else {
		    $jailoptions .= " -o noinaddrany";
		}
		last SWITCH;
	    };
	    /^ROUTING$/ && do {
		if ($val) {
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		    $jailoptions .= " -o routing -i 127.0.0.1 ";
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		    $jailflags |= $JAIL_ROUTING;
		    #
		    # If the jail gets routing privs, then it must get
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		    # its own routing table. 
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		    #
		    $routetabid   = getnextrtabid();
		    $jailoptions .= " -r $routetabid";
		}
		last SWITCH;
	    };
	    /^DEVMEM$/ && do {
		$jailflags |= $JAIL_DEVMEM;
		last SWITCH;
	    };
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 	    /^IPADDRS$/ && do {
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		# Comma separated list of IPs
		my @iplist = split(",", $val);

		foreach my $ip (@iplist) {
		    if ($ip =~ /(\d+\.\d+\.\d+\.\d+)/) {
			$jailoptions .= " -i $1";
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			push(@jailips, $1);
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		    }
		}
 		last SWITCH;
 	    };
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	}
    }
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    #
    # If there is no IP for the jail, must restrict the port range of
    # it. Otherwise it has it own IP, and there is no need to.
    # 
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    if (! defined($IPALIAS)) {
	if (defined($portrange)) {
	    $jailoptions .= " -p $portrange";
	}
	else {
	    fatal("Must have a port range if jail ip equals host ip!");
	}
	print("SSHD port is $sshdport\n");
    }
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    system("sysctl jail.inetraw_allowed=1 >/dev/null 2>&1");
    system("sysctl jail.bpf_allowed=1 >/dev/null 2>&1");
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    system("sysctl jail.inaddrany_allowed=1 >/dev/null 2>&1");
    system("sysctl jail.multiip_allowed=1 >/dev/null 2>&1");
    system("sysctl net.link.ether.inet.useloopback=0 >/dev/null 2>&1");

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    if ($?) {
	print("Special jail options are NOT supported!\n");
	$jailoptions = "";
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	$jailflags   = 0;
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	return 0;
    }
    print("Special jail options are supported: '$jailoptions'\n");
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    return 0;
}

#
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# Append a list of static routes to the rc.conf file. This basically
# augments the list of static routes that tmcd tells us to install. 
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#
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sub addcontrolroutes()
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{
    my ($rc)   = @_;
    my $count  = 0;

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    #
    # XXX use address for localhost.  For some reason the route command is
    # going to the DNS before using the hosts file, despite the host.conf
    # file.
    # 
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    my $routerip  = getcnetrouter($USEVCNETROUTES);
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    my $localhost = "127.0.0.1";
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    my $hostip    = `cat $BOOTDIR/myip`;
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    chomp($hostip);

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    push(@controlroutes, "default $routerip");
    push(@controlroutes, "$localhost -interface lo0");
    push(@controlroutes, "$hostip $localhost");
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    if ($IP ne $hostip) {
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	my $net;

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	#
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	# Setup a route for all jails on this node, to the loopback.
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	#
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	$net = inet_ntoa(inet_aton($IP) & inet_aton("255.255.255.0"));
	push(@controlroutes, "-net $net -interface lo0 255.255.255.0");
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	#
	# All other jails are reachable via the control net interface.
	#
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	# N.B. privnet is setup first even before the default route.
	# This is because the gateway for the default route is on the
	# privnet, but our control net interface is not (because it has
	# a 255.255.255.255 netmask by virtue of being an alias on the
	# real control interface).  Thus there is no way to use the
	# default route until the privnet route is up (ARP complains
	# about "host is not on local network").
	#
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	$net = inet_ntoa(inet_aton($IP) & inet_aton($IPMASK));
	push(@controlroutes, "-net $net -interface $phys_cnet_if $IPMASK");
	
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	#
	# If using the virtual control net for routes, also make sure that
	# nodes are reachable with their real control net addresses directly.
	#
	if ($USEVCNETROUTES) {
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	    my $mask = getcnetmask(0);
	    
	    $net = inet_ntoa(inet_aton($hostip) & inet_aton($mask));
	    push(@controlroutes,
		 "-net $net -netmask $mask -interface $phys_cnet_if");
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	}
1162
    }
1163
1164

    #
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1166
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1171
    # Now a list of routes for each of the IPs the jail has access
    # to. The idea here is to override the interface route such that
    # traffic to the local interface goes through lo0 instead. This
    # avoids going through traffic shaping when, say, pinging your own
    # interface!
    # 
    foreach my $ip (@jailips) {
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1180
	push(@controlroutes, "$ip -interface lo0");
    }

    #
    # Now add them:
    #
    foreach my $route (@controlroutes) {
	print("Adding route: '$route'\n");
	mysystem("route add -rtabid $routetabid $route");
1181
    }
1182
1183
    return 0;
}
1184
1185
1186
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1188
1189
1190
1191
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1194
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1196
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1199
1200
1201
1202
1203
1204
1205
1206

#
# Ug, with NFS mounts inside the jail, we need to be really careful.
#
sub removevnodedir($)
{
    my ($dir) = @_;

    if (-d "$dir/root" && !rmdir("$dir/root")) {
	die("*** $0:\n".
	    "    $dir/root is not empty! This is very bad!\n");
    }
    system("rm -rf $dir");
}

#
# Get a free routing table ID. This should eventually come from the
# kernel, but for now just use a file with a number in it. 
#
sub getnextrtabid()
{
    my $nextrtabid = 1;

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1208
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1210
1211
1212
1213
1214
1215
    #
    # If the vnodeid is what we think (pcvmXXX-YYY) then just use the YYY
    # part. At some point we need better control of this from Emulab Central.
    #
    if (defined($idnumber)) {
	$nextrtabid = $idnumber;
	goto gotit;
    }

1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
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1233
1234
1235
1236
1237
1238
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1240
    #
    # The chances of a race are low, but need to deal with it anyway.
    #
    my $lockfile  = "/var/emulab/lock/rtabid";
    my $rtabidfile= "/var/emulab/db/rtabid";

    open(LOCK, ">>$lockfile") ||
	fatal("Could not open $lockfile\n");
    
    while (flock(LOCK, LOCK_EX|LOCK_NB) == 0) {
	print "Waiting to get lock for $lockfile\n";
	sleep(1);
    }
    if (-e $rtabidfile) {
	my $rtabid = `cat $rtabidfile`;
	if ($rtabid =~ /^(\d*)$/) {
	    $nextrtabid = $1 + 1;
	}
	else {
	    close(LOCK);
	    fatal("Bad data in $rtabidfile!");
	}
    }
    system("echo $nextrtabid > $rtabidfile");
    close(LOCK);
1241
1242

  gotit:
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1244
1245
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1247
1248
    #
    # Flush that routing table so its pristine. Again, this should be
    # handled in the kernel.
    #
    system("route flush -rtabid $nextrtabid");
    
1249
1250
    return $nextrtabid;
}
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
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1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315

#
# Return the number of alias on the jailhost control interface
#
sub jailcnetaliases()
{
    my $count = 0;

    if (open(IFC, "ifconfig $phys_cnet_if |")) {
	while (<IFC>) {
	    if ($_ =~ /inet ([0-9\.]*) netmask 0xffffffff/) {
		my $host = $1;
		if (inet_ntoa(inet_aton($host) & inet_aton($JAILCNETMASK)) eq
		    $JAILCNET) {
		    $count++;
		}
	    }
	}
	close(IFC);
    }
    return $count;
}

sub setcnethostalias($)
{
    my ($vnodeip) = @_;

    mysystem("ifconfig $phys_cnet_if alias $vnodeip netmask 255.255.255.255");

    if (!$USEVCNETROUTES) {
	return;
    }

    #
    # If the jail's IP is part of the local virtual control net,
    # make sure the physical host has an alias on it as well.
    #
    # The convention is that .0 is the physical host alias.
    #
    my $cnalias = inet_aton($vnodeip);
    if ((inet_ntoa($cnalias & inet_aton($JAILCNETMASK)) eq $JAILCNET) &&
	jailcnetaliases() == 1) {
	my $palias = inet_ntoa($cnalias & inet_aton("255.255.255.0"));
	mysystem("ifconfig $phys_cnet_if alias $palias netmask $JAILCNETMASK");
    }
}

sub clearcnethostalias($)
{
    my ($vnodeip) = @_;

    system("ifconfig $phys_cnet_if -alias $vnodeip");

    if (!$USEVCNETROUTES) {
	return;
    }

    #
    # If the jail's IP is part of the local virtual control net,
    # and we were the last jail, remove the physical host's alias.
    #
    my $cnalias = inet_aton($vnodeip);
    if ((inet_ntoa($cnalias & inet_aton($JAILCNETMASK)) eq $JAILCNET) &&
	jailcnetaliases() == 0) {
	my $palias = inet_ntoa($cnalias & inet_aton("255.255.255.0"));
1316
	system("ifconfig $phys_cnet_if -alias $palias");
1317
1318
1319
    }
}

1320
sub getcnetrouter($)
1321
{
1322
1323
    my ($usevcnet) = @_;

1324
1325
    my $routerip;

1326
    if (!$usevcnet) {
1327
1328
1329
1330
1331
1332
1333
1334
1335
	$routerip = `cat $BOOTDIR/routerip`;
	chomp($routerip);
    } else {
	$routerip = inet_ntoa(inet_aton($JAILCNET) |
			      inet_aton("0.0.0.1"));
    }

    return $routerip;
}
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353

sub getcnetmask($)
{
    my ($usevcnet) = @_;

    my $cnetmask = "255.255.255.0";

    if (!$usevcnet) {
	if (-e "$BOOTDIR/mynetmask") {
	    $cnetmask = `cat $BOOTDIR/mynetmask`;
	    chomp($cnetmask);
	}
    } else {
	$cnetmask = $JAILCNETMASK;
    }

    return $cnetmask;
}
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369

#
# Check for free vn device.
#
sub CheckFreeVN($$)
{
    my ($vn, $file) = @_;
    
    # Make sure the dev entries exist!
    if (! -e "/dev/vn${vn}") {
	mysystem("(cd /dev; ./MAKEDEV vn${vn})");
    }
	
    system("vnconfig -c vn${vn} $file");
    return ($? ? 0 : 1);
}