package PVE::CLI::pct;
    
use strict;
use warnings;

use POSIX;
use Fcntl;
use File::Copy 'copy';
use Term::ReadLine;

use PVE::SafeSyslog;
use PVE::Tools qw(extract_param);
use PVE::Cluster;
use PVE::INotify;
use PVE::RPCEnvironment;
use PVE::JSONSchema qw(get_standard_option);
use PVE::CLIHandler;
use PVE::API2::LXC;
use PVE::API2::LXC::Config;
use PVE::API2::LXC::Status;
use PVE::API2::LXC::Snapshot;

use Data::Dumper;

use base qw(PVE::CLIHandler);

my $nodename = PVE::INotify::nodename();

my $upid_exit = sub {
    my $upid = shift;
    my $status = PVE::Tools::upid_read_status($upid);
    exit($status eq 'OK' ? 0 : -1);
};

sub read_password {
    my $term = new Term::ReadLine ('pct');
    my $attribs = $term->Attribs;
    $attribs->{redisplay_function} = $attribs->{shadow_redisplay};
    my $input = $term->readline('Enter password: ');
    my $conf = $term->readline('Retype password: ');
    die "Passwords do not match.\n" if ($input ne $conf);
    return $input;
}

__PACKAGE__->register_method ({
    name => 'unlock',
    path => 'unlock',
    method => 'PUT',
    description => "Unlock the VM.",
    parameters => {
	additionalProperties => 0,
	properties => {
	    vmid => get_standard_option('pve-vmid', { completion => \&PVE::LXC::complete_ctid }),
	},
    },
    returns => { type => 'null'},
    code => sub {
	my ($param) = @_;

	my $vmid = $param->{vmid};

	PVE::LXC::Config->remove_lock($vmid);

	return undef;
    }});

__PACKAGE__->register_method ({
    name => 'console',
    path => 'console',
    method => 'GET',
    description => "Launch a console for the specified container.",
    parameters => {
    	additionalProperties => 0,
	properties => {
	    vmid => get_standard_option('pve-vmid', { completion => \&PVE::LXC::complete_ctid_running }),
	},
    },
    returns => { type => 'null' },

    code => sub {
	my ($param) = @_;

	# test if container exists on this node
	my $conf = PVE::LXC::Config->load_config($param->{vmid});

	my $cmd = PVE::LXC::get_console_command($param->{vmid}, $conf);
	exec(@$cmd);
    }});

__PACKAGE__->register_method ({
    name => 'enter',
    path => 'enter',
    method => 'GET',
    description => "Launch a shell for the specified container.",
    parameters => {
    	additionalProperties => 0,
	properties => {
	    vmid => get_standard_option('pve-vmid', { completion => \&PVE::LXC::complete_ctid_running }),
	},
    },
    returns => { type => 'null' },

    code => sub {
	my ($param) = @_;

	my $vmid = $param->{vmid};

	# test if container exists on this node
	PVE::LXC::Config->load_config($vmid);

	die "Error: container '$vmid' not running!\n" if !PVE::LXC::check_running($vmid);

	exec('lxc-attach', '-n',  $vmid);
    }});

__PACKAGE__->register_method ({
    name => 'exec',
    path => 'exec',
    method => 'GET',
    description => "Launch a command inside the specified container.",
    parameters => {
    	additionalProperties => 0,
	properties => {
	    vmid => get_standard_option('pve-vmid', { completion => \&PVE::LXC::complete_ctid_running }),
	    'extra-args' => get_standard_option('extra-args'),
	},
    },
    returns => { type => 'null' },

    code => sub {
	my ($param) = @_;

	# test if container exists on this node
	PVE::LXC::Config->load_config($param->{vmid});

	if (!@{$param->{'extra-args'}}) {
	    die "missing command";
	}
	exec('lxc-attach', '-n', $param->{vmid}, '--', @{$param->{'extra-args'}});
    }});

__PACKAGE__->register_method ({
    name => 'fsck',
    path => 'fsck',
    method => 'PUT',
    description => "Run a filesystem check (fsck) on a container volume.",
    parameters => {
	additionalProperties => 0,
	properties => {
	    vmid => get_standard_option('pve-vmid', { completion => \&PVE::LXC::complete_ctid_stopped }),
	    force => {
		optional => 1,
		type => 'boolean',
		description => "Force checking, even if the filesystem seems clean",
		default => 0,
	    },
	    device => {
		optional => 1,
		type => 'string',
		description => "A volume on which to run the filesystem check",
		enum => [PVE::LXC::Config->mountpoint_names()],
	    },
	},
    },
    returns => { type => 'null' },
    code => sub {

	my ($param) = @_;
	my $vmid = $param->{'vmid'};
	my $device = defined($param->{'device'}) ? $param->{'device'} : 'rootfs';

	my $command = ['fsck', '-a', '-l'];
	push(@$command, '-f') if $param->{force};

	# critical path: all of this will be done while the container is locked
	my $do_fsck = sub {

	    my $conf = PVE::LXC::Config->load_config($vmid);
	    my $storage_cfg = PVE::Storage::config();

	    defined($conf->{$device}) || die "cannot run command on unexisting mountpoint $device\n";

	    my $mount_point = $device eq 'rootfs' ? PVE::LXC::Config->parse_ct_rootfs($conf->{$device}) :
		PVE::LXC::Config->parse_ct_mountpoint($conf->{$device});

	    my $volid = $mount_point->{volume};

	    my $path;
	    my $storage_id = PVE::Storage::parse_volume_id($volid, 1);

	    if ($storage_id) {
		my (undef, undef, undef, undef, undef, undef, $format) =
		    PVE::Storage::parse_volname($storage_cfg, $volid);

		die "unable to run fsck for '$volid' (format == $format)\n"
		    if $format ne 'raw';

		$path = PVE::Storage::path($storage_cfg, $volid);

	    } else {
		if (($volid =~ m|^/.+|) && (-b $volid)) {
		    # pass block devices directly
		    $path = $volid;
		} else {
		    die "path '$volid' does not point to a block device\n";
		}
	    }

	    push(@$command, $path);

	    PVE::LXC::check_running($vmid) &&
		die "cannot run fsck on active container\n";

	    PVE::Tools::run_command($command);
	};

	PVE::LXC::Config->lock_config($vmid, $do_fsck);
	return undef;
    }});

__PACKAGE__->register_method({
    name => 'mount',
    path => 'mount',
    method => 'POST',
    description => "Mount the container's filesystem on the host. " .
		   "This will hold a lock on the container and is meant for emergency maintenance only " .
		   "as it will prevent further operations on the container other than start and stop.",
    parameters => {
	additionalProperties => 0,
	properties => {
	    vmid => get_standard_option('pve-vmid', { completion => \&PVE::LXC::complete_ctid }),
	},
    },
    returns => { type => 'null' },
    code => sub {
	my ($param) = @_;

	my $rpcenv = PVE::RPCEnvironment::get();

	my $vmid = extract_param($param, 'vmid');
	my $storecfg = PVE::Storage::config();
	PVE::LXC::Config->lock_config($vmid, sub {
	    my $conf = PVE::LXC::Config->set_lock($vmid, 'mounted');
	    PVE::LXC::mount_all($vmid, $storecfg, $conf);
	});
	return undef;
    }});

__PACKAGE__->register_method({
    name => 'unmount',
    path => 'unmount',
    method => 'POST',
    description => "Unmount the container's filesystem.",
    parameters => {
	additionalProperties => 0,
	properties => {
	    vmid => get_standard_option('pve-vmid', { completion => \&PVE::LXC::complete_ctid }),
	},
    },
    returns => { type => 'null' },
    code => sub {
	my ($param) = @_;

	my $rpcenv = PVE::RPCEnvironment::get();

	my $vmid = extract_param($param, 'vmid');
	my $storecfg = PVE::Storage::config();
	PVE::LXC::Config->lock_config($vmid, sub {
	    my $conf = PVE::LXC::Config->load_config($vmid);
	    PVE::LXC::umount_all($vmid, $storecfg, $conf, 0);
	    PVE::LXC::Config->remove_lock($vmid, 'mounted');
	});
	return undef;
    }});

# File creation with specified ownership and permissions.
# User and group can be names or decimal numbers.
# Permissions are explicit (not affected by umask) and can be numeric with the
# usual 0/0x prefixes for octal/hex.
sub create_file {
    my ($path, $perms, $user, $group) = @_;
    my ($uid, $gid);
    if (defined($user)) {
	if ($user =~ /^\d+$/) {
	    $uid = int($user);
	} else {
	    $uid = getpwnam($user) or die "failed to get uid for: $user\n"
	}
    }
    if (defined($group)) {
	if ($group =~ /^\d+$/) {
	    $gid = int($group);
	} else {
	    $gid = getgrnam($group) or die "failed to get gid for: $group\n"
	}
    }

    if (defined($perms)) {
	$! = 0;
	my ($mode, $unparsed) = POSIX::strtoul($perms, 0);
	die "invalid mode: '$perms'\n" if $perms eq '' || $unparsed > 0 || $!;
	$perms = $mode;
    }

    my $fd;
    if (sysopen($fd, $path, O_WRONLY | O_CREAT | O_EXCL, 0)) {
	$perms = 0666 & ~umask if !defined($perms);
    } else {
	# If the path previously existed then we do not care about left-over
	# file descriptors even if the permissions/ownership is changed.
	sysopen($fd, $path, O_WRONLY | O_CREAT | O_TRUNC)
	    or die "failed to create file: $path: $!\n";
    }

    my $trunc = 0;

    if (defined($perms)) {
	$trunc = 1;
	chmod($perms, $fd);
    }

    if (defined($uid) || defined($gid)) {
	$trunc = 1;
	my ($fuid, $fgid) = (stat($fd))[4,5] if !defined($uid) || !defined($gid);
	$uid = $fuid if !defined($uid);
	$gid = $fgid if !defined($gid);
	chown($uid, $gid, $fd)
	    or die "failed to change file owner: $!\n";
    }
    return $fd;
}

__PACKAGE__->register_method({
    name => 'pull',
    path => 'pull',
    method => 'PUT',
    description => "Copy a file from the container to the local system.",
    parameters => {
	additionalProperties => 0,
	properties => {
	    vmid => get_standard_option('pve-vmid', { completion => \&PVE::LXC::complete_ctid }),
	    path => {
		type => 'string',
		description => "Path to a file inside the container to pull.",
	    },
	    destination => {
		type => 'string',
		description => "Destination",
	    },
	    user => {
		type => 'string',
		description => 'Owner user name or id.',
		optional => 1,
	    },
	    group => {
		type => 'string',
		description => 'Owner group name or id.',
		optional => 1,
	    },
	    perms => {
		type => 'string',
		description => 'File permissions to use.',
		optional => 1,
	    },
	},
    },
    returns => {
	type => 'string',
	description => "the task ID.",
    },
    code => sub {
	my ($param) = @_;

	my $rpcenv = PVE::RPCEnvironment::get();

	my $vmid = extract_param($param, 'vmid');
	my $path = extract_param($param, 'path');
	my $dest = extract_param($param, 'destination');

	my $perms = extract_param($param, 'perms');
	my $user = extract_param($param, 'user');
	my $group = extract_param($param, 'group');

	my $code = sub {
	    my $running = PVE::LXC::check_running($vmid);
	    die "can only pull files from a running VM" if !$running;

	    my $realcmd = sub {
		my $pid = PVE::LXC::find_lxc_pid($vmid);
		# Avoid symlink issues by opening the files from inside the
		# corresponding namespaces.
		my $destfd = create_file($dest, $perms, $user, $group);

		sysopen my $mntnsfd, "/proc/$pid/ns/mnt", O_RDONLY
		    or die "failed to open the container's mount namespace\n";
		PVE::Tools::setns(fileno($mntnsfd), PVE::Tools::CLONE_NEWNS)
		    or die "failed to enter the container's mount namespace\n";
		close($mntnsfd);
		chdir('/') or die "failed to change to container root directory\n";

		open my $srcfd, '<', $path
		    or die "failed to open $path: $!\n";

		copy($srcfd, $destfd);
	    };

	    # This avoids having to setns() back to our namespace.
	    return $rpcenv->fork_worker('pull_file', $vmid, undef, $realcmd);
	};

	return PVE::LXC::Config->lock_config($vmid, $code);
    }});

__PACKAGE__->register_method({
    name => 'push',
    path => 'push',
    method => 'PUT',
    description => "Copy a local file to the container.",
    parameters => {
	additionalProperties => 0,
	properties => {
	    vmid => get_standard_option('pve-vmid', { completion => \&PVE::LXC::complete_ctid }),
	    file => {
		type => 'string',
		description => "Path to a local file.",
	    },
	    destination => {
		type => 'string',
		description => "Destination inside the container to write to.",
	    },
	    user => {
		type => 'string',
		description => 'Owner user name or id. When using a name it must exist inside the container.',
		optional => 1,
	    },
	    group => {
		type => 'string',
		description => 'Owner group name or id. When using a name it must exist inside the container.',
		optional => 1,
	    },
	    perms => {
		type => 'string',
		description => 'File permissions to use.',
		optional => 1,
	    },
	},
    },
    returns => {
	type => 'string',
	description => "the task ID.",
    },
    code => sub {
	my ($param) = @_;

	my $rpcenv = PVE::RPCEnvironment::get();

	my $vmid = extract_param($param, 'vmid');
	my $file = extract_param($param, 'file');
	my $dest = extract_param($param, 'destination');

	my $perms = extract_param($param, 'perms');
	my $user = extract_param($param, 'user');
	my $group = extract_param($param, 'group');

	my $code = sub {
	    my $running = PVE::LXC::check_running($vmid);
	    die "can only push files to a running VM" if !$running;

	    my $conf = PVE::LXC::Config->load_config($vmid);
	    my $unprivileged = $conf->{unprivileged};

	    my $realcmd = sub {
		my $pid = PVE::LXC::find_lxc_pid($vmid);
		# We open the file then enter the container's mount - and for
		# unprivileged containers - user namespace and then create the
		# file. This avoids symlink attacks as a symlink cannot point
		# outside the namespace and our own access is equivalent to the
		# container-local's root user. Also the user-passed -user and
		# -group parameters will use the container-local's user and
		# group names.
		sysopen my $srcfd, $file, O_RDONLY
		    or die "failed to open $file for reading\n";

		sysopen my $mntnsfd, "/proc/$pid/ns/mnt", O_RDONLY
		    or die "failed to open the container's mount namespace\n";
		my $usernsfd;
		if ($unprivileged) {
		    sysopen $usernsfd, "/proc/$pid/ns/user", O_RDONLY
			or die "failed to open the container's user namespace\n";
		}

		PVE::Tools::setns(fileno($mntnsfd), PVE::Tools::CLONE_NEWNS)
		    or die "failed to enter the container's mount namespace\n";
		close($mntnsfd);
		chdir('/') or die "failed to change to container root directory\n";

		if ($unprivileged) {
		    PVE::Tools::setns(fileno($usernsfd), PVE::Tools::CLONE_NEWUSER)
			or die "failed to enter the container's user namespace\n";
		    close($usernsfd);
		    POSIX::setgid(0) or die "setgid failed: $!\n";
		    POSIX::setuid(0) or die "setuid failed: $!\n";
		}

		my $destfd = create_file($dest, $perms, $user, $group);
		copy($srcfd, $destfd);
	    };

	    # This avoids having to setns() back to our namespace.
	    return $rpcenv->fork_worker('push_file', $vmid, undef, $realcmd);
	};

	return PVE::LXC::Config->lock_config($vmid, $code);
    }});

our $cmddef = {
    list=> [ 'PVE::API2::LXC', 'vmlist', [], { node => $nodename }, sub {
	my $res = shift;
	return if !scalar(@$res);
	my $format = "%-10s %-10s %-12s %-20s\n";
	printf($format, 'VMID', 'Status', 'Lock', 'Name');
	foreach my $d (sort {$a->{vmid} <=> $b->{vmid} } @$res) {
	    printf($format, $d->{vmid}, $d->{status}, $d->{lock}, $d->{name});
	}
    }],
    config => [ "PVE::API2::LXC::Config", 'vm_config', ['vmid'], 
		{ node => $nodename }, sub {
		    my $config = shift;
		    foreach my $k (sort (keys %$config)) {
			next if $k eq 'digest';
			my $v = $config->{$k};
			if ($k eq 'description') {
			    $v = PVE::Tools::encode_text($v);
			}
			print "$k: $v\n";
		    }
		}],
    set => [ 'PVE::API2::LXC::Config', 'update_vm', ['vmid'], { node => $nodename }],

    resize => [ "PVE::API2::LXC", 'resize_vm', ['vmid', 'disk', 'size'], { node => $nodename } ],
    
    create => [ 'PVE::API2::LXC', 'create_vm', ['vmid', 'ostemplate'], { node => $nodename }, $upid_exit ],
    restore => [ 'PVE::API2::LXC', 'create_vm', ['vmid', 'ostemplate'], { node => $nodename, restore => 1 }, $upid_exit ],

    start => [ 'PVE::API2::LXC::Status', 'vm_start', ['vmid'], { node => $nodename }, $upid_exit],
    suspend => [ 'PVE::API2::LXC::Status', 'vm_suspend', ['vmid'], { node => $nodename }, $upid_exit],
    resume => [ 'PVE::API2::LXC::Status', 'vm_resume', ['vmid'], { node => $nodename }, $upid_exit],
    shutdown => [ 'PVE::API2::LXC::Status', 'vm_shutdown', ['vmid'], { node => $nodename }, $upid_exit],
    stop => [ 'PVE::API2::LXC::Status', 'vm_stop', ['vmid'], { node => $nodename }, $upid_exit],
    
    clone => [ "PVE::API2::LXC", 'clone_vm', ['vmid', 'newid'], { node => $nodename }, $upid_exit ],
    migrate => [ "PVE::API2::LXC", 'migrate_vm', ['vmid', 'target'], { node => $nodename }, $upid_exit],
    
    console => [ __PACKAGE__, 'console', ['vmid']],
    enter => [ __PACKAGE__, 'enter', ['vmid']],
    unlock => [ __PACKAGE__, 'unlock', ['vmid']],
    exec => [ __PACKAGE__, 'exec', ['vmid', 'extra-args']],
    fsck => [ __PACKAGE__, 'fsck', ['vmid']],

    mount => [ __PACKAGE__, 'mount', ['vmid']],
    unmount => [ __PACKAGE__, 'unmount', ['vmid']],
    push => [ __PACKAGE__, 'push', ['vmid', 'file', 'destination']],
    pull => [ __PACKAGE__, 'pull', ['vmid', 'path', 'destination']],
    
    destroy => [ 'PVE::API2::LXC', 'destroy_vm', ['vmid'], 
		 { node => $nodename }, $upid_exit ],

    snapshot => [ "PVE::API2::LXC::Snapshot", 'snapshot', ['vmid', 'snapname'],
		  { node => $nodename } , $upid_exit ],

    delsnapshot => [ "PVE::API2::LXC::Snapshot", 'delsnapshot', ['vmid', 'snapname'], { node => $nodename } , $upid_exit ],

    listsnapshot => [ "PVE::API2::LXC::Snapshot", 'list', ['vmid'], { node => $nodename },
		      sub {
			  my $res = shift;
			  foreach my $e (@$res) {
			      my $headline = $e->{description} || 'no-description';
			      $headline =~ s/\n.*//sg;
			      my $parent = $e->{parent} // 'no-parent';
			      printf("%-20s %-20s %s\n", $e->{name}, $parent, $headline);
			  }
		      }],

    rollback => [ "PVE::API2::LXC::Snapshot", 'rollback', ['vmid', 'snapname'], { node => $nodename } , $upid_exit ],

    template => [ "PVE::API2::LXC", 'template', ['vmid'], { node => $nodename }],
};


1;

__END__

=head1 NAME

pct - Tool to manage Linux Containers (LXC) on Proxmox VE

=head1 SYNOPSIS

=include synopsis

=head1 DESCRIPTION

pct is a tool to manages Linux Containers (LXC). You can create
and destroy containers, and control execution
(start/stop/suspend/resume). Besides that, you can use pct to set
parameters in the associated config file, like network configuration or
memory.

=head1 EXAMPLES

Create a container based on a Debian template
(provided you downloaded the template via the webgui before)

pct create 100 /var/lib/vz/template/cache/debian-8.0-standard_8.0-1_amd64.tar.gz

Start a container

pct start 100

Start a login session via getty

pct console 100

Enter the lxc namespace and run a shell as root user

pct enter 100

Display the configuration

pct config 100

Add a network interface called eth0, bridged to the host bridge vmbr0,
set the address and gateway, while it's running

pct set 100 -net0 name=eth0,bridge=vmbr0,ip=192.168.15.147/24,gw=192.168.15.1

Reduce the memory of the container to 512MB

pct set -memory 512 100

=head1 FILES

/etc/pve/lxc/<vmid>.conf

Configuration file for the container <vmid>

=head1 SEE ALSO

L<B<qm(1)>>, L<B<pvesh(1)>>

=include pve_copyright
