Fix #1383: pmxcfs: use memdb_tree_entry_free()

[pve-cluster.git] / data / PVE / Cluster.pm

package PVE::Cluster;

use strict;
use warnings;
use POSIX qw(EEXIST);
use File::stat qw();
use Socket;
use Storable qw(dclone);
use IO::File;
use MIME::Base64;
use Digest::SHA;
use Digest::HMAC_SHA1;
use Net::SSLeay;
use PVE::Tools;
use PVE::INotify;
use PVE::IPCC;
use PVE::SafeSyslog;
use PVE::JSONSchema;
use PVE::Network;
use JSON;
use RRDs;
use Encode;
use UUID;
use base 'Exporter';

our @EXPORT_OK = qw(
cfs_read_file
cfs_write_file
cfs_register_file
cfs_lock_file);

use Data::Dumper; # fixme: remove

# x509 certificate utils

my $basedir = "/etc/pve";
my $authdir = "$basedir/priv";
my $lockdir = "/etc/pve/priv/lock";

my $authprivkeyfn = "$authdir/authkey.key";
my $authpubkeyfn = "$basedir/authkey.pub";
my $pveca_key_fn = "$authdir/pve-root-ca.key";
my $pveca_srl_fn = "$authdir/pve-root-ca.srl";
my $pveca_cert_fn = "$basedir/pve-root-ca.pem";
# this is just a secret accessable by the web browser
# and is used for CSRF prevention
my $pvewww_key_fn = "$basedir/pve-www.key";

# ssh related files
my $ssh_rsa_id_priv = "/root/.ssh/id_rsa";
my $ssh_rsa_id = "/root/.ssh/id_rsa.pub";
my $ssh_host_rsa_id = "/etc/ssh/ssh_host_rsa_key.pub";
my $sshglobalknownhosts = "/etc/ssh/ssh_known_hosts";
my $sshknownhosts = "/etc/pve/priv/known_hosts";
my $sshauthkeys = "/etc/pve/priv/authorized_keys";
my $sshd_config_fn = "/etc/ssh/sshd_config";
my $rootsshauthkeys = "/root/.ssh/authorized_keys";
my $rootsshauthkeysbackup = "${rootsshauthkeys}.org";
my $rootsshconfig = "/root/.ssh/config";

my $observed = {
    'vzdump.cron' => 1,
    'storage.cfg' => 1,
    'datacenter.cfg' => 1,
    'replication.cfg' => 1,
    'corosync.conf' => 1,
    'corosync.conf.new' => 1,
    'user.cfg' => 1,
    'domains.cfg' => 1,
    'priv/shadow.cfg' => 1,
    '/qemu-server/' => 1,
    '/openvz/' => 1,
    '/lxc/' => 1,
    'ha/crm_commands' => 1,
    'ha/manager_status' => 1,
    'ha/resources.cfg' => 1,
    'ha/groups.cfg' => 1,
    'ha/fence.cfg' => 1,
    'status.cfg' => 1,
};

# only write output if something fails
sub run_silent_cmd {
    my ($cmd) = @_;

    my $outbuf = '';

    my $record_output = sub {
	$outbuf .= shift;
	$outbuf .= "\n";
    };

    eval {
	PVE::Tools::run_command($cmd, outfunc => $record_output,
				errfunc => $record_output);
    };

    my $err = $@;

    if ($err) {
	print STDERR $outbuf;
	die $err;
    }
}

sub check_cfs_quorum {
    my ($noerr) = @_;

    # note: -w filename always return 1 for root, so wee need
    # to use File::lstat here
    my $st = File::stat::lstat("$basedir/local");
    my $quorate = ($st && (($st->mode & 0200) != 0));

    die "cluster not ready - no quorum?\n" if !$quorate && !$noerr;

    return $quorate;
}

sub check_cfs_is_mounted {
    my ($noerr) = @_;

    my $res = -l "$basedir/local";

    die "pve configuration filesystem not mounted\n"
	if !$res && !$noerr;

    return $res;
}

sub gen_local_dirs {
    my ($nodename) = @_;

    check_cfs_is_mounted();

    my @required_dirs = (
	"$basedir/priv",
	"$basedir/nodes",
	"$basedir/nodes/$nodename",
	"$basedir/nodes/$nodename/lxc",
	"$basedir/nodes/$nodename/qemu-server",
	"$basedir/nodes/$nodename/openvz",
	"$basedir/nodes/$nodename/priv");

    foreach my $dir (@required_dirs) {
	if (! -d $dir) {
	    mkdir($dir) || $! == EEXIST || die "unable to create directory '$dir' - $!\n";
	}
    }
}

sub gen_auth_key {

    return if -f "$authprivkeyfn";

    check_cfs_is_mounted();

    mkdir $authdir || $! == EEXIST || die "unable to create dir '$authdir' - $!\n";

    run_silent_cmd(['openssl', 'genrsa', '-out', $authprivkeyfn, '2048']);

    run_silent_cmd(['openssl', 'rsa', '-in', $authprivkeyfn, '-pubout', '-out', $authpubkeyfn]);
}

sub gen_pveca_key {

    return if -f $pveca_key_fn;

    eval {
	run_silent_cmd(['openssl', 'genrsa', '-out', $pveca_key_fn, '4096']);
    };

    die "unable to generate pve ca key:\n$@" if $@;
}

sub gen_pveca_cert {

    if (-f $pveca_key_fn && -f $pveca_cert_fn) {
	return 0;
    }

    gen_pveca_key();

    # we try to generate an unique 'subject' to avoid browser problems
    # (reused serial numbers, ..)
    my $uuid;
    UUID::generate($uuid);
    my $uuid_str;
    UUID::unparse($uuid, $uuid_str);

    eval {
	# wrap openssl with faketime to prevent bug #904
	run_silent_cmd(['faketime', 'yesterday', 'openssl', 'req', '-batch',
			'-days', '3650', '-new', '-x509', '-nodes', '-key',
			$pveca_key_fn, '-out', $pveca_cert_fn, '-subj',
			"/CN=Proxmox Virtual Environment/OU=$uuid_str/O=PVE Cluster Manager CA/"]);
    };

    die "generating pve root certificate failed:\n$@" if $@;

    return 1;
}

sub gen_pve_ssl_key {
    my ($nodename) = @_;

    die "no node name specified" if !$nodename;

    my $pvessl_key_fn = "$basedir/nodes/$nodename/pve-ssl.key";

    return if -f $pvessl_key_fn;

    eval {
	run_silent_cmd(['openssl', 'genrsa', '-out', $pvessl_key_fn, '2048']);
    };

    die "unable to generate pve ssl key for node '$nodename':\n$@" if $@;
}

sub gen_pve_www_key {

    return if -f $pvewww_key_fn;

    eval {
	run_silent_cmd(['openssl', 'genrsa', '-out', $pvewww_key_fn, '2048']);
    };

    die "unable to generate pve www key:\n$@" if $@;
}

sub update_serial {
    my ($serial) = @_;

    PVE::Tools::file_set_contents($pveca_srl_fn, $serial);
}

sub gen_pve_ssl_cert {
    my ($force, $nodename, $ip) = @_;

    die "no node name specified" if !$nodename;
    die "no IP specified" if !$ip;

    my $pvessl_cert_fn = "$basedir/nodes/$nodename/pve-ssl.pem";

    return if !$force && -f $pvessl_cert_fn;

    my $names = "IP:127.0.0.1,IP:::1,DNS:localhost";

    my $rc = PVE::INotify::read_file('resolvconf');

    $names .= ",IP:$ip";

    my $fqdn = $nodename;

    $names .= ",DNS:$nodename";

    if ($rc && $rc->{search}) {
	$fqdn = $nodename . "." . $rc->{search};
	$names .= ",DNS:$fqdn";
    }

    my $sslconf = <<__EOD;
RANDFILE = /root/.rnd
extensions = v3_req

[ req ]
default_bits = 2048
distinguished_name = req_distinguished_name
req_extensions = v3_req
prompt = no
string_mask = nombstr

[ req_distinguished_name ]
organizationalUnitName = PVE Cluster Node
organizationName = Proxmox Virtual Environment
commonName = $fqdn

[ v3_req ]
basicConstraints = CA:FALSE
extendedKeyUsage = serverAuth
subjectAltName = $names
__EOD

    my $cfgfn = "/tmp/pvesslconf-$$.tmp";
    my $fh = IO::File->new ($cfgfn, "w");
    print $fh $sslconf;
    close ($fh);

    my $reqfn = "/tmp/pvecertreq-$$.tmp";
    unlink $reqfn;

    my $pvessl_key_fn = "$basedir/nodes/$nodename/pve-ssl.key";
    eval {
	run_silent_cmd(['openssl', 'req', '-batch', '-new', '-config', $cfgfn,
			'-key', $pvessl_key_fn, '-out', $reqfn]);
    };

    if (my $err = $@) {
	unlink $reqfn;
	unlink $cfgfn;
	die "unable to generate pve certificate request:\n$err";
    }

    update_serial("0000000000000000") if ! -f $pveca_srl_fn;

    eval {
	# wrap openssl with faketime to prevent bug #904
	run_silent_cmd(['faketime', 'yesterday', 'openssl', 'x509', '-req',
			'-in', $reqfn, '-days', '3650', '-out', $pvessl_cert_fn,
			'-CAkey', $pveca_key_fn, '-CA', $pveca_cert_fn,
			'-CAserial', $pveca_srl_fn, '-extfile', $cfgfn]);
    };

    if (my $err = $@) {
	unlink $reqfn;
	unlink $cfgfn;
	die "unable to generate pve ssl certificate:\n$err";
    }

    unlink $cfgfn;
    unlink $reqfn;
}

sub gen_pve_node_files {
    my ($nodename, $ip, $opt_force) = @_;

    gen_local_dirs($nodename);

    gen_auth_key();

    # make sure we have a (cluster wide) secret
    # for CSRFR prevention
    gen_pve_www_key();

    # make sure we have a (per node) private key
    gen_pve_ssl_key($nodename);

    # make sure we have a CA
    my $force = gen_pveca_cert();

    $force = 1 if $opt_force;

    gen_pve_ssl_cert($force, $nodename, $ip);
}

my $vzdump_cron_dummy = <<__EOD;
# cluster wide vzdump cron schedule
# Atomatically generated file - do not edit

PATH="/usr/sbin:/usr/bin:/sbin:/bin"

__EOD

sub gen_pve_vzdump_symlink {

    my $filename = "/etc/pve/vzdump.cron";

    my $link_fn = "/etc/cron.d/vzdump";

    if ((-f $filename) && (! -l $link_fn)) {
	rename($link_fn, "/root/etc_cron_vzdump.org"); # make backup if file exists
	symlink($filename, $link_fn);
    }
}

sub gen_pve_vzdump_files {

    my $filename = "/etc/pve/vzdump.cron";

    PVE::Tools::file_set_contents($filename, $vzdump_cron_dummy)
	if ! -f $filename;

    gen_pve_vzdump_symlink();
};

my $versions = {};
my $vmlist = {};
my $clinfo = {};

my $ipcc_send_rec = sub {
    my ($msgid, $data) = @_;

    my $res = PVE::IPCC::ipcc_send_rec($msgid, $data);

    die "ipcc_send_rec failed: $!\n" if !defined($res) && ($! != 0);

    return $res;
};

my $ipcc_send_rec_json = sub {
    my ($msgid, $data) = @_;

    my $res = PVE::IPCC::ipcc_send_rec($msgid, $data);

    die "ipcc_send_rec failed: $!\n" if !defined($res) && ($! != 0);

    return decode_json($res);
};

my $ipcc_get_config = sub {
    my ($path) = @_;

    my $bindata = pack "Z*", $path;
    my $res = PVE::IPCC::ipcc_send_rec(6, $bindata);
    if (!defined($res)) {
	return undef if ($! != 0);
	return '';
    }

    return $res;
};

my $ipcc_get_status = sub {
    my ($name, $nodename) = @_;

    my $bindata = pack "Z[256]Z[256]", $name, ($nodename || "");
    return PVE::IPCC::ipcc_send_rec(5, $bindata);
};

my $ipcc_update_status = sub {
    my ($name, $data) = @_;

    my $raw = ref($data) ? encode_json($data) : $data;
    # update status
    my $bindata = pack "Z[256]Z*", $name, $raw;

    return &$ipcc_send_rec(4, $bindata);
};

my $ipcc_log = sub {
    my ($priority, $ident, $tag, $msg) = @_;

    my $bindata = pack "CCCZ*Z*Z*", $priority, bytes::length($ident) + 1,
    bytes::length($tag) + 1, $ident, $tag, $msg;

    return &$ipcc_send_rec(7, $bindata);
};

my $ipcc_get_cluster_log = sub {
    my ($user, $max) = @_;

    $max = 0 if !defined($max);

    my $bindata = pack "VVVVZ*", $max, 0, 0, 0, ($user || "");
    return &$ipcc_send_rec(8, $bindata);
};

my $ccache = {};

sub cfs_update {
    eval {
	my $res = &$ipcc_send_rec_json(1);
	#warn "GOT1: " . Dumper($res);
	die "no starttime\n" if !$res->{starttime};

	if (!$res->{starttime} || !$versions->{starttime} ||
	    $res->{starttime} != $versions->{starttime}) {
	    #print "detected changed starttime\n";
	    $vmlist = {};
	    $clinfo = {};
	    $ccache = {};
	}

	$versions = $res;
    };
    my $err = $@;
    if ($err) {
	$versions = {};
	$vmlist = {};
	$clinfo = {};
	$ccache = {};
	warn $err;
    }

    eval {
	if (!$clinfo->{version} || $clinfo->{version} != $versions->{clinfo}) {
	    #warn "detected new clinfo\n";
	    $clinfo = &$ipcc_send_rec_json(2);
	}
    };
    $err = $@;
    if ($err) {
	$clinfo = {};
	warn $err;
    }

    eval {
	if (!$vmlist->{version} || $vmlist->{version} != $versions->{vmlist}) {
	    #warn "detected new vmlist1\n";
	    $vmlist = &$ipcc_send_rec_json(3);
	}
    };
    $err = $@;
    if ($err) {
	$vmlist = {};
	warn $err;
    }
}

sub get_vmlist {
    return $vmlist;
}

sub get_clinfo {
    return $clinfo;
}

sub get_members {
    return $clinfo->{nodelist};
}

sub get_nodelist {

    my $nodelist = $clinfo->{nodelist};

    my $result = [];

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

    if (!$nodelist || !$nodelist->{$nodename}) {
	return [ $nodename ];
    }

    return [ keys %$nodelist ];
}

sub broadcast_tasklist {
    my ($data) = @_;

    eval {
	&$ipcc_update_status("tasklist", $data);
    };

    warn $@ if $@;
}

my $tasklistcache = {};

sub get_tasklist {
    my ($nodename) = @_;

    my $kvstore = $versions->{kvstore} || {};

    my $nodelist = get_nodelist();

    my $res = [];
    foreach my $node (@$nodelist) {
	next if $nodename && ($nodename ne $node);
	eval {
	    my $ver = $kvstore->{$node}->{tasklist} if $kvstore->{$node};
	    my $cd = $tasklistcache->{$node};
	    if (!$cd || !$ver || !$cd->{version} ||
		($cd->{version} != $ver)) {
		my $raw = &$ipcc_get_status("tasklist", $node) || '[]';
		my $data = decode_json($raw);
		push @$res, @$data;
		$cd = $tasklistcache->{$node} = {
		    data => $data,
		    version => $ver,
		};
	    } elsif ($cd && $cd->{data}) {
		push @$res, @{$cd->{data}};
	    }
	};
	my $err = $@;
	syslog('err', $err) if $err;
    }

    return $res;
}

sub broadcast_rrd {
    my ($rrdid, $data) = @_;

    eval {
	&$ipcc_update_status("rrd/$rrdid", $data);
    };
    my $err = $@;

    warn $err if $err;
}

my $last_rrd_dump = 0;
my $last_rrd_data = "";

sub rrd_dump {

    my $ctime = time();

    my $diff = $ctime - $last_rrd_dump;
    if ($diff < 2) {
	return $last_rrd_data;
    }

    my $raw;
    eval {
	$raw = &$ipcc_send_rec(10);
    };
    my $err = $@;

    if ($err) {
	warn $err;
	return {};
    }

    my $res = {};

    if ($raw) {
	while ($raw =~ s/^(.*)\n//) {
	    my ($key, @ela) = split(/:/, $1);
	    next if !$key;
	    next if !(scalar(@ela) > 1);
	    $res->{$key} = [ map { $_ eq 'U' ? undef : $_ } @ela ];
	}
    }

    $last_rrd_dump = $ctime;
    $last_rrd_data = $res;

    return $res;
}

sub create_rrd_data {
    my ($rrdname, $timeframe, $cf) = @_;

    my $rrddir = "/var/lib/rrdcached/db";

    my $rrd = "$rrddir/$rrdname";

    my $setup = {
	hour =>  [ 60, 70 ],
	day  =>  [ 60*30, 70 ],
	week =>  [ 60*180, 70 ],
	month => [ 60*720, 70 ],
	year =>  [ 60*10080, 70 ],
    };

    my ($reso, $count) = @{$setup->{$timeframe}};
    my $ctime  = $reso*int(time()/$reso);
    my $req_start = $ctime - $reso*$count;

    $cf = "AVERAGE" if !$cf;

    my @args = (
	"-s" => $req_start,
	"-e" => $ctime - 1,
	"-r" => $reso,
	);

    my $socket = "/var/run/rrdcached.sock";
    push @args, "--daemon" => "unix:$socket" if -S $socket;

    my ($start, $step, $names, $data) = RRDs::fetch($rrd, $cf, @args);

    my $err = RRDs::error;
    die "RRD error: $err\n" if $err;

    die "got wrong time resolution ($step != $reso)\n"
	if $step != $reso;

    my $res = [];
    my $fields = scalar(@$names);
    for my $line (@$data) {
	my $entry = { 'time' => $start };
	$start += $step;
	for (my $i = 0; $i < $fields; $i++) {
	    my $name = $names->[$i];
	    if (defined(my $val = $line->[$i])) {
		$entry->{$name} = $val;
	    } else {
		# leave empty fields undefined
		# maybe make this configurable?
	    }
	}
	push @$res, $entry;
    }

    return $res;
}

sub create_rrd_graph {
    my ($rrdname, $timeframe, $ds, $cf) = @_;

    # Using RRD graph is clumsy - maybe it
    # is better to simply fetch the data, and do all display
    # related things with javascript (new extjs html5 graph library).

    my $rrddir = "/var/lib/rrdcached/db";

    my $rrd = "$rrddir/$rrdname";

    my @ids = PVE::Tools::split_list($ds);

    my $ds_txt = join('_', @ids);

    my $filename = "${rrd}_${ds_txt}.png";

    my $setup = {
	hour =>  [ 60, 60 ],
	day  =>  [ 60*30, 70 ],
	week =>  [ 60*180, 70 ],
	month => [ 60*720, 70 ],
	year =>  [ 60*10080, 70 ],
    };

    my ($reso, $count) = @{$setup->{$timeframe}};

    my @args = (
	"--imgformat" => "PNG",
	"--border" => 0,
	"--height" => 200,
	"--width" => 800,
	"--start" => - $reso*$count,
	"--end" => 'now' ,
	"--lower-limit" => 0,
	);

    my $socket = "/var/run/rrdcached.sock";
    push @args, "--daemon" => "unix:$socket" if -S $socket;

    my @coldef = ('#00ddff', '#ff0000');

    $cf = "AVERAGE" if !$cf;

    my $i = 0;
    foreach my $id (@ids) {
	my $col = $coldef[$i++] || die "fixme: no color definition";
	push @args, "DEF:${id}=$rrd:${id}:$cf";
	my $dataid = $id;
	if ($id eq 'cpu' || $id eq 'iowait') {
	    push @args, "CDEF:${id}_per=${id},100,*";
	    $dataid = "${id}_per";
	}
	push @args, "LINE2:${dataid}${col}:${id}";
    }

    push @args, '--full-size-mode';

    # we do not really store data into the file
    my $res = RRDs::graphv('', @args);

    my $err = RRDs::error;
    die "RRD error: $err\n" if $err;

    return { filename => $filename, image => $res->{image} };
}

# a fast way to read files (avoid fuse overhead)
sub get_config {
    my ($path) = @_;

    return &$ipcc_get_config($path);
}

sub get_cluster_log {
    my ($user, $max) = @_;

    return &$ipcc_get_cluster_log($user, $max);
}

my $file_info = {};

sub cfs_register_file {
    my ($filename, $parser, $writer) = @_;

    $observed->{$filename} || die "unknown file '$filename'";

    die "file '$filename' already registered" if $file_info->{$filename};

    $file_info->{$filename} = {
	parser => $parser,
	writer => $writer,
    };
}

my $ccache_read = sub {
    my ($filename, $parser, $version) = @_;

    $ccache->{$filename} = {} if !$ccache->{$filename};

    my $ci = $ccache->{$filename};

    if (!$ci->{version} || !$version || $ci->{version} != $version) {
	# we always call the parser, even when the file does not exists
	# (in that case $data is undef)
	my $data = get_config($filename);
	$ci->{data} = &$parser("/etc/pve/$filename", $data);
	$ci->{version} = $version;
    }

    my $res = ref($ci->{data}) ? dclone($ci->{data}) : $ci->{data};

    return $res;
};

sub cfs_file_version {
    my ($filename) = @_;

    my $version;
    my $infotag;
    if ($filename =~ m!^nodes/[^/]+/(openvz|lxc|qemu-server)/(\d+)\.conf$!) {
	my ($type, $vmid) = ($1, $2);
	if ($vmlist && $vmlist->{ids} && $vmlist->{ids}->{$vmid}) {
	    $version = $vmlist->{ids}->{$vmid}->{version};
	}
	$infotag = "/$type/";
    } else {
	$infotag = $filename;
	$version = $versions->{$filename};
    }

    my $info = $file_info->{$infotag} ||
	die "unknown file type '$filename'\n";

    return wantarray ? ($version, $info) : $version;
}

sub cfs_read_file {
    my ($filename) = @_;

    my ($version, $info) = cfs_file_version($filename);
    my $parser = $info->{parser};

    return &$ccache_read($filename, $parser, $version);
}

sub cfs_write_file {
    my ($filename, $data) = @_;

    my ($version, $info) = cfs_file_version($filename);

    my $writer = $info->{writer} || die "no writer defined";

    my $fsname = "/etc/pve/$filename";

    my $raw = &$writer($fsname, $data);

    if (my $ci = $ccache->{$filename}) {
	$ci->{version} = undef;
    }

    PVE::Tools::file_set_contents($fsname, $raw);
}

my $cfs_lock = sub {
    my ($lockid, $timeout, $code, @param) = @_;

    my $res;

    # this timeout is for aquire the lock
    $timeout = 10 if !$timeout;

    my $filename = "$lockdir/$lockid";

    my $msg = "can't aquire cfs lock '$lockid'";

    eval {

	mkdir $lockdir;

	if (! -d $lockdir) {
	    die "$msg: pve cluster filesystem not online.\n";
	}

        local $SIG{ALRM} = sub { die "got lock request timeout\n"; };

        alarm ($timeout);

	if (!(mkdir $filename)) {
	    print STDERR "trying to aquire cfs lock '$lockid' ...";
 	    while (1) {
		if (!(mkdir $filename)) {
		    (utime 0, 0, $filename); # cfs unlock request
		} else {
		    print STDERR " OK\n";
		    last;
		}
		sleep(1);
	    }
	}

	# fixed command timeout: cfs locks have a timeout of 120
	# using 60 gives us another 60 seconds to abort the task
	alarm(60);
	local $SIG{ALRM} = sub { die "got lock timeout - aborting command\n"; };

	cfs_update(); # make sure we read latest versions inside code()

	$res = &$code(@param);

	alarm(0);
    };

    my $err = $@;

    alarm(0);

    if ($err && ($err eq "got lock request timeout\n") &&
	!check_cfs_quorum()){
	$err = "$msg: no quorum!\n";
    }

    if (!$err || $err !~ /^got lock timeout -/) {
	rmdir $filename; # cfs unlock
    }

    if ($err) {
        $@ = $err;
        return undef;
    }

    $@ = undef;

    return $res;
};

sub cfs_lock_file {
    my ($filename, $timeout, $code, @param) = @_;

    my $info = $observed->{$filename} || die "unknown file '$filename'";

    my $lockid = "file-$filename";
    $lockid =~ s/[.\/]/_/g;

    &$cfs_lock($lockid, $timeout, $code, @param);
}

sub cfs_lock_storage {
    my ($storeid, $timeout, $code, @param) = @_;

    my $lockid = "storage-$storeid";

    &$cfs_lock($lockid, $timeout, $code, @param);
}

sub cfs_lock_domain {
    my ($domainname, $timeout, $code, @param) = @_;

    my $lockid = "domain-$domainname";

    &$cfs_lock($lockid, $timeout, $code, @param);
}

my $log_levels = {
    "emerg" => 0,
    "alert" => 1,
    "crit" => 2,
    "critical" => 2,
    "err" => 3,
    "error" => 3,
    "warn" => 4,
    "warning" => 4,
    "notice" => 5,
    "info" => 6,
    "debug" => 7,
};

sub log_msg {
   my ($priority, $ident, $msg) = @_;

   if (my $tmp = $log_levels->{$priority}) {
       $priority = $tmp;
   }

   die "need numeric log priority" if $priority !~ /^\d+$/;

   my $tag = PVE::SafeSyslog::tag();

   $msg = "empty message" if !$msg;

   $ident = "" if !$ident;
   $ident = encode("ascii", $ident,
		   sub { sprintf "\\u%04x", shift });

   my $ascii = encode("ascii", $msg, sub { sprintf "\\u%04x", shift });

   if ($ident) {
       syslog($priority, "<%s> %s", $ident, $ascii);
   } else {
       syslog($priority, "%s", $ascii);
   }

   eval { &$ipcc_log($priority, $ident, $tag, $ascii); };

   syslog("err", "writing cluster log failed: $@") if $@;
}

sub check_vmid_unused {
    my ($vmid, $noerr) = @_;

    my $vmlist = get_vmlist();

    my $d = $vmlist->{ids}->{$vmid};
    return 1 if !defined($d);

    return undef if $noerr;

    my $vmtypestr =  $d->{type} eq 'qemu' ? 'VM' : 'CT';
    die "$vmtypestr $vmid already exists on node '$d->{node}'\n";
}

sub check_node_exists {
    my ($nodename, $noerr) = @_;

    my $nodelist = $clinfo->{nodelist};
    return 1 if $nodelist && $nodelist->{$nodename};

    return undef if $noerr;

    die "no such cluster node '$nodename'\n";
}

# this is also used to get the IP of the local node
sub remote_node_ip {
    my ($nodename, $noerr) = @_;

    my $nodelist = $clinfo->{nodelist};
    if ($nodelist && $nodelist->{$nodename}) {
	if (my $ip = $nodelist->{$nodename}->{ip}) {
	    return $ip if !wantarray;
	    my $family = $nodelist->{$nodename}->{address_family};
	    if (!$family) {
		$nodelist->{$nodename}->{address_family} =
		    $family =
		    PVE::Tools::get_host_address_family($ip);
	    }
	    return wantarray ? ($ip, $family) : $ip;
	}
    }

    # fallback: try to get IP by other means
    return PVE::Network::get_ip_from_hostname($nodename, $noerr);
}

sub get_local_migration_ip {
    my ($migration_network, $noerr) = @_;

    my $cidr = $migration_network;

    if (!defined($cidr)) {
	my $dc_conf = cfs_read_file('datacenter.cfg');
	$cidr = $dc_conf->{migration}->{network}
	  if defined($dc_conf->{migration}->{network});
    }

    if (defined($cidr)) {
	my $ips = PVE::Network::get_local_ip_from_cidr($cidr);

	die "could not get migration ip: no IP address configured on local " .
	    "node for network '$cidr'\n" if !$noerr && (scalar(@$ips) == 0);

	die "could not get migration ip: multiple IP address configured for " .
	    "network '$cidr'\n" if !$noerr && (scalar(@$ips) > 1);

	return @$ips[0];
    }

    return undef;
};

# ssh related utility functions

sub ssh_merge_keys {
    # remove duplicate keys in $sshauthkeys
    # ssh-copy-id simply add keys, so the file can grow to large

    my $data = '';
    if (-f $sshauthkeys) {
	$data = PVE::Tools::file_get_contents($sshauthkeys, 128*1024);
	chomp($data);
    }

    my $found_backup;
    if (-f $rootsshauthkeysbackup) {
	$data .= "\n";
	$data .= PVE::Tools::file_get_contents($rootsshauthkeysbackup, 128*1024);
	chomp($data);
	$found_backup = 1;
    }

    # always add ourself
    if (-f $ssh_rsa_id) {
	my $pub = PVE::Tools::file_get_contents($ssh_rsa_id);
	chomp($pub);
	$data .= "\n$pub\n";
    }

    my $newdata = "";
    my $vhash = {};
    my @lines = split(/\n/, $data);
    foreach my $line (@lines) {
	if ($line !~ /^#/ && $line =~ m/(^|\s)ssh-(rsa|dsa)\s+(\S+)\s+\S+$/) {
            next if $vhash->{$3}++;
	}
	$newdata .= "$line\n";
    }

    PVE::Tools::file_set_contents($sshauthkeys, $newdata, 0600);

    if ($found_backup && -l $rootsshauthkeys) {
	# everything went well, so we can remove the backup
	unlink $rootsshauthkeysbackup;
    }
}

sub setup_sshd_config {
    my ($start_sshd) = @_;

    my $conf = PVE::Tools::file_get_contents($sshd_config_fn);

    return if $conf =~ m/^PermitRootLogin\s+yes\s*$/m;

    if ($conf !~ s/^#?PermitRootLogin.*$/PermitRootLogin yes/m) {
	chomp $conf;
	$conf .= "\nPermitRootLogin yes\n";
    }

    PVE::Tools::file_set_contents($sshd_config_fn, $conf);

    my $cmd = $start_sshd ? 'reload-or-restart' : 'reload-or-try-restart';
    PVE::Tools::run_command(['systemctl', $cmd, 'sshd']);
}

sub setup_rootsshconfig {

    # create ssh key if it does not exist
    if (! -f $ssh_rsa_id) {
	mkdir '/root/.ssh/';
	system ("echo|ssh-keygen -t rsa -N '' -b 2048 -f ${ssh_rsa_id_priv}");
    }

    # create ssh config if it does not exist
    if (! -f $rootsshconfig) {
        mkdir '/root/.ssh';
        if (my $fh = IO::File->new($rootsshconfig, O_CREAT|O_WRONLY|O_EXCL, 0640)) {
            # this is the default ciphers list from debian openssl0.9.8 except blowfish is added as prefered
            print $fh "Ciphers blowfish-cbc,aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc\n";
            close($fh);
        }
    }
}

sub setup_ssh_keys {

    mkdir $authdir;

    my $import_ok;

    if (! -f $sshauthkeys) {
	my $old;
	if (-f $rootsshauthkeys) {
	    $old = PVE::Tools::file_get_contents($rootsshauthkeys, 128*1024);
	}
	if (my $fh = IO::File->new ($sshauthkeys, O_CREAT|O_WRONLY|O_EXCL, 0400)) {
	    PVE::Tools::safe_print($sshauthkeys, $fh, $old) if $old;
	    close($fh);
	    $import_ok = 1;
	}
    }

    warn "can't create shared ssh key database '$sshauthkeys'\n"
	if ! -f $sshauthkeys;

    if (-f $rootsshauthkeys && ! -l $rootsshauthkeys) {
	if (!rename($rootsshauthkeys , $rootsshauthkeysbackup)) {
	    warn "rename $rootsshauthkeys failed - $!\n";
	}
    }

    if (! -l $rootsshauthkeys) {
	symlink $sshauthkeys, $rootsshauthkeys;
    }

    if (! -l $rootsshauthkeys) {
	warn "can't create symlink for ssh keys '$rootsshauthkeys' -> '$sshauthkeys'\n";
    } else {
	unlink $rootsshauthkeysbackup if $import_ok;
    }
}

sub ssh_unmerge_known_hosts {
    return if ! -l $sshglobalknownhosts;

    my $old = '';
    $old = PVE::Tools::file_get_contents($sshknownhosts, 128*1024)
	if -f $sshknownhosts;

    PVE::Tools::file_set_contents($sshglobalknownhosts, $old);
}

sub ssh_merge_known_hosts {
    my ($nodename, $ip_address, $createLink) = @_;

    die "no node name specified" if !$nodename;
    die "no ip address specified" if !$ip_address;

    mkdir $authdir;

    if (! -f $sshknownhosts) {
	if (my $fh = IO::File->new($sshknownhosts, O_CREAT|O_WRONLY|O_EXCL, 0600)) {
	    close($fh);
	}
    }

    my $old = PVE::Tools::file_get_contents($sshknownhosts, 128*1024);

    my $new = '';

    if ((! -l $sshglobalknownhosts) && (-f $sshglobalknownhosts)) {
	$new = PVE::Tools::file_get_contents($sshglobalknownhosts, 128*1024);
    }

    my $hostkey = PVE::Tools::file_get_contents($ssh_host_rsa_id);
    # Note: file sometimes containe emty lines at start, so we use multiline match
    die "can't parse $ssh_host_rsa_id" if $hostkey !~ m/^(ssh-rsa\s\S+)(\s.*)?$/m;
    $hostkey = $1;

    my $data = '';
    my $vhash = {};

    my $found_nodename;
    my $found_local_ip;

    my $merge_line = sub {
	my ($line, $all) = @_;

	if ($line =~ m/^(\S+)\s(ssh-rsa\s\S+)(\s.*)?$/) {
	    my $key = $1;
	    my $rsakey = $2;
	    if (!$vhash->{$key}) {
		$vhash->{$key} = 1;
		if ($key =~ m/\|1\|([^\|\s]+)\|([^\|\s]+)$/) {
		    my $salt = decode_base64($1);
		    my $digest = $2;
		    my $hmac = Digest::HMAC_SHA1->new($salt);
		    $hmac->add($nodename);
		    my $hd = $hmac->b64digest . '=';
		    if ($digest eq $hd) {
			if ($rsakey eq $hostkey) {
			    $found_nodename = 1;
			    $data .= $line;
			}
			return;
		    }
		    $hmac = Digest::HMAC_SHA1->new($salt);
		    $hmac->add($ip_address);
		    $hd = $hmac->b64digest . '=';
		    if ($digest eq $hd) {
			if ($rsakey eq $hostkey) {
			    $found_local_ip = 1;
			    $data .= $line;
			}
			return;
		    }
		}
		$data .= $line;
	    }
	} elsif ($all) {
	    $data .= $line;
	}
    };

    while ($old && $old =~ s/^((.*?)(\n|$))//) {
	my $line = "$2\n";
	next if $line =~ m/^\s*$/; # skip empty lines
	next if $line =~ m/^#/; # skip comments
	&$merge_line($line, 1);
    }

    while ($new && $new =~ s/^((.*?)(\n|$))//) {
	my $line = "$2\n";
	next if $line =~ m/^\s*$/; # skip empty lines
	next if $line =~ m/^#/; # skip comments
	&$merge_line($line);
    }

    my $addIndex = $$;
    my $add_known_hosts_entry  = sub {
	my ($name, $hostkey) = @_;
	$addIndex++;
	my $hmac = Digest::HMAC_SHA1->new("$addIndex" . time());
	my $b64salt = $hmac->b64digest . '=';
	$hmac = Digest::HMAC_SHA1->new(decode_base64($b64salt));
	$hmac->add($name);
	my $digest = $hmac->b64digest . '=';
	$data .= "|1|$b64salt|$digest $hostkey\n";
    };

    if (!$found_nodename || !$found_local_ip) {
	&$add_known_hosts_entry($nodename, $hostkey) if !$found_nodename;
	&$add_known_hosts_entry($ip_address, $hostkey) if !$found_local_ip;
    }

    PVE::Tools::file_set_contents($sshknownhosts, $data);

    return if !$createLink;

    unlink $sshglobalknownhosts;
    symlink $sshknownhosts, $sshglobalknownhosts;

    warn "can't create symlink for ssh known hosts '$sshglobalknownhosts' -> '$sshknownhosts'\n"
	if ! -l $sshglobalknownhosts;

}

my $migration_format = {
    type => {
	default_key => 1,
	type => 'string',
	enum => ['secure', 'insecure'],
	description => "Migration traffic is encrypted using an SSH tunnel by " .
	  "default. On secure, completely private networks this can be " .
	  "disabled to increase performance.",
	default => 'secure',
    },
    network => {
	optional => 1,
	type => 'string', format => 'CIDR',
	format_description => 'CIDR',
	description => "CIDR of the (sub) network that is used for migration."
    },
};

my $datacenter_schema = {
    type => "object",
    additionalProperties => 0,
    properties => {
	keyboard => {
	    optional => 1,
	    type => 'string',
	    description => "Default keybord layout for vnc server.",
	    enum => PVE::Tools::kvmkeymaplist(),
	},
	language => {
	    optional => 1,
	    type => 'string',
	    description => "Default GUI language.",
	    enum => [ 'en', 'de' ],
	},
	http_proxy => {
	    optional => 1,
	    type => 'string',
	    description => "Specify external http proxy which is used for downloads (example: 'http://username:password\@host:port/')",
	    pattern => "http://.*",
	},
	migration_unsecure => {
	    optional => 1,
	    type => 'boolean',
	    description => "Migration is secure using SSH tunnel by default. " .
	      "For secure private networks you can disable it to speed up " .
	      "migration. Deprecated, use the 'migration' property instead!",
	},
	migration => {
	    optional => 1,
	    type => 'string', format => $migration_format,
	    description => "For cluster wide migration settings.",
	},
	console => {
	    optional => 1,
	    type => 'string',
	    description => "Select the default Console viewer. You can either use the builtin java applet (VNC), an external virt-viewer comtatible application (SPICE), or an HTML5 based viewer (noVNC).",
	    enum => ['applet', 'vv', 'html5'],
	},
	email_from => {
	    optional => 1,
	    type => 'string',
	    format => 'email-opt',
	    description => "Specify email address to send notification from (default is root@\$hostname)",
	},
	max_workers => {
	    optional => 1,
	    type => 'integer',
	    minimum => 1,
	    description => "Defines how many workers (per node) are maximal started ".
	      " on actions like 'stopall VMs' or task from the ha-manager.",
	},
	fencing => {
	    optional => 1,
	    type => 'string',
	    default => 'watchdog',
	    enum => [ 'watchdog', 'hardware', 'both' ],
	    description => "Set the fencing mode of the HA cluster. Hardware mode " .
	      "needs a valid configuration of fence devices in /etc/pve/ha/fence.cfg." .
	      " With both all two modes are used." .
	      "\n\nWARNING: 'hardware' and 'both' are EXPERIMENTAL & WIP",
	},
	mac_prefix => {
	    optional => 1,
	    type => 'string',
	    pattern => qr/[a-f0-9]{2}(?::[a-f0-9]{2}){0,2}:?/i,
	    description => 'Prefix for autogenerated MAC addresses.',
	},
    },
};

# make schema accessible from outside (for documentation)
sub get_datacenter_schema { return $datacenter_schema };

sub parse_datacenter_config {
    my ($filename, $raw) = @_;

    my $res = PVE::JSONSchema::parse_config($datacenter_schema, $filename, $raw // '');

    if (my $migration = $res->{migration}) {
	$res->{migration} = PVE::JSONSchema::parse_property_string($migration_format, $migration);
    }

    # for backwards compatibility only, new migration property has precedence
    if (defined($res->{migration_unsecure})) {
	if (defined($res->{migration}->{type})) {
	    warn "deprecated setting 'migration_unsecure' and new 'migration: type' " .
	      "set at same time! Ignore 'migration_unsecure'\n";
	} else {
	    $res->{migration}->{type} = ($res->{migration_unsecure}) ? 'insecure' : 'secure';
	}
    }

    return $res;
}

sub write_datacenter_config {
    my ($filename, $cfg) = @_;

    # map deprecated setting to new one
    if (defined($cfg->{migration_unsecure}) && !defined($cfg->{migration})) {
	my $migration_unsecure = delete $cfg->{migration_unsecure};
	$cfg->{migration}->{type} = ($migration_unsecure) ? 'insecure' : 'secure';
    }

    return PVE::JSONSchema::dump_config($datacenter_schema, $filename, $cfg);
}

cfs_register_file('datacenter.cfg',
		  \&parse_datacenter_config,
		  \&write_datacenter_config);

# a very simply parser ...
sub parse_corosync_conf {
    my ($filename, $raw) = @_;

    return {} if !$raw;

    my $digest = Digest::SHA::sha1_hex(defined($raw) ? $raw : '');

    $raw =~ s/#.*$//mg;
    $raw =~ s/\r?\n/ /g;
    $raw =~ s/\s+/ /g;
    $raw =~ s/^\s+//;
    $raw =~ s/\s*$//;

    my @tokens = split(/\s/, $raw);

    my $conf = { section => 'main', children => [] };

    my $stack = [];
    my $section = $conf;

    while (defined(my $token = shift @tokens)) {
	my $nexttok = $tokens[0];

	if ($nexttok && ($nexttok eq '{')) {
	    shift @tokens; # skip '{'
	    my $new_section = {
		section => $token,
		children => [],
	    };
	    push @{$section->{children}}, $new_section;
	    push @$stack, $section;
	    $section = $new_section;
	    next;
	}

	if ($token eq '}') {
	    $section = pop @$stack;
	    die "parse error - uncexpected '}'\n" if !$section;
	    next;
	}

	my $key = $token;
	die "missing ':' after key '$key'\n" if ! ($key =~ s/:$//);

	die "parse error - no value for '$key'\n" if !defined($nexttok);
	my $value = shift @tokens;

	push @{$section->{children}}, { key => $key, value => $value };
    }

    $conf->{digest} = $digest;

    return $conf;
}

my $dump_corosync_section;
$dump_corosync_section = sub {
    my ($section, $prefix) = @_;

    my $raw = $prefix . $section->{section} . " {\n";

    my @list = grep { defined($_->{key}) } @{$section->{children}};
    foreach my $child (sort {$a->{key} cmp $b->{key}} @list) {
	$raw .= $prefix . "  $child->{key}: $child->{value}\n";
    }

    @list = grep { defined($_->{section}) } @{$section->{children}};
    foreach my $child (sort {$a->{section} cmp $b->{section}} @list) {
	$raw .= &$dump_corosync_section($child, "$prefix  ");
    }

    $raw .= $prefix . "}\n\n";

    return $raw;

};

sub write_corosync_conf {
    my ($filename, $conf) = @_;

    my $raw = '';

    my $prefix = '';

    die "no main section" if $conf->{section} ne 'main';

    my @list = grep { defined($_->{key}) } @{$conf->{children}};
    foreach my $child (sort {$a->{key} cmp $b->{key}} @list) {
	$raw .= "$child->{key}: $child->{value}\n";
    }

    @list = grep { defined($_->{section}) } @{$conf->{children}};
    foreach my $child (sort {$a->{section} cmp $b->{section}} @list) {
	$raw .= &$dump_corosync_section($child, $prefix);
    }

    return $raw;
}

sub corosync_conf_version {
    my ($conf, $noerr, $new_value) = @_;

    foreach my $child (@{$conf->{children}}) {
	next if !defined($child->{section});
	if ($child->{section} eq 'totem') {
	    foreach my $e (@{$child->{children}}) {
		next if !defined($e->{key});
		if ($e->{key} eq 'config_version') {
		    if ($new_value) {
			$e->{value} = $new_value;
			return $new_value;
		    } elsif (my $version = int($e->{value})) {
			return $version;
		    }
		    last;
		}
	    }
	}
    }

    return undef if $noerr;

    die "invalid corosync config - unable to read version\n";
}

# read only - use "rename corosync.conf.new corosync.conf" to write
PVE::Cluster::cfs_register_file('corosync.conf', \&parse_corosync_conf);
# this is read/write
PVE::Cluster::cfs_register_file('corosync.conf.new', \&parse_corosync_conf,
				\&write_corosync_conf);

sub check_corosync_conf_exists {
    my ($silent) = @_;

    $silent = $silent // 0;

    my $exists = -f "$basedir/corosync.conf";

    warn "Corosync config '$basedir/corosync.conf' does not exist - is this node part of a cluster?\n"
	if !$silent && !$exists;

    return $exists;
}

sub corosync_update_nodelist {
    my ($conf, $nodelist) = @_;

    delete $conf->{digest};

    my $version = corosync_conf_version($conf);
    corosync_conf_version($conf, undef, $version + 1);

    my $children = [];
    foreach my $v (values %$nodelist) {
	next if !($v->{ring0_addr} || $v->{name});
	my $kv = [];
	foreach my $k (keys %$v) {
	    push @$kv, { key => $k, value => $v->{$k} };
	}
	my $ns = { section => 'node', children => $kv };
	push @$children, $ns;
    }

    foreach my $main (@{$conf->{children}}) {
	next if !defined($main->{section});
	if ($main->{section} eq 'nodelist') {
	    $main->{children} = $children;
	    last;
	}
    }


    cfs_write_file("corosync.conf.new", $conf);

    rename("/etc/pve/corosync.conf.new", "/etc/pve/corosync.conf")
	|| die "activate  corosync.conf.new failed - $!\n";
}

sub corosync_nodelist {
    my ($conf) = @_;

    my $nodelist = {};

    foreach my $main (@{$conf->{children}}) {
	next if !defined($main->{section});
	if ($main->{section} eq 'nodelist') {
	    foreach my $ne (@{$main->{children}}) {
		next if !defined($ne->{section}) || ($ne->{section} ne 'node');
		my $node = { quorum_votes => 1 };
		my $name;
		foreach my $child (@{$ne->{children}}) {
		    next if !defined($child->{key});
		    $node->{$child->{key}} = $child->{value};
		    # use 'name' over 'ring0_addr' if set
		    if ($child->{key} eq 'name') {
			delete $nodelist->{$name} if $name;
			$name = $child->{value};
			$nodelist->{$name} = $node;
		    } elsif(!$name && $child->{key} eq 'ring0_addr') {
			$name = $child->{value};
			$nodelist->{$name} = $node;
		    }
		}
	    }
	}
    }

    return $nodelist;
}

# get a hash representation of the corosync config totem section
sub corosync_totem_config {
    my ($conf) = @_;

    my $res = {};

    foreach my $main (@{$conf->{children}}) {
	next if !defined($main->{section}) ||
	    $main->{section} ne 'totem';

	foreach my $e (@{$main->{children}}) {

	    if ($e->{section} && $e->{section} eq 'interface') {
		my $entry = {};

		$res->{interface} = {};

		foreach my $child (@{$e->{children}}) {
		    next if !defined($child->{key});
		    $entry->{$child->{key}} = $child->{value};
		    if($child->{key} eq 'ringnumber') {
			$res->{interface}->{$child->{value}} = $entry;
		    }
		}

	    } elsif  ($e->{key}) {
		$res->{$e->{key}} = $e->{value};
	    }
	}
    }

    return $res;
}

# X509 Certificate cache helper

my $cert_cache_nodes = {};
my $cert_cache_timestamp = time();
my $cert_cache_fingerprints = {};

sub update_cert_cache {
    my ($update_node, $clear) = @_;

    syslog('info', "Clearing outdated entries from certificate cache")
	if $clear;

    $cert_cache_timestamp = time() if !defined($update_node);

    my $node_list = defined($update_node) ?
	[ $update_node ] : [ keys %$cert_cache_nodes ];

    foreach my $node (@$node_list) {
	my $clear_old = sub {
	    if (my $old_fp = $cert_cache_nodes->{$node}) {
		# distrust old fingerprint
		delete $cert_cache_fingerprints->{$old_fp};
		# ensure reload on next proxied request
		delete $cert_cache_nodes->{$node};
	    }
	};

	my $cert_path = "/etc/pve/nodes/$node/pve-ssl.pem";
	my $custom_cert_path = "/etc/pve/nodes/$node/pveproxy-ssl.pem";

	$cert_path = $custom_cert_path if -f $custom_cert_path;

	my $cert;
	eval {
	    my $bio = Net::SSLeay::BIO_new_file($cert_path, 'r');
	    $cert = Net::SSLeay::PEM_read_bio_X509($bio);
	    Net::SSLeay::BIO_free($bio);
	};
	my $err = $@;
	if ($err || !defined($cert)) {
	    &$clear_old() if $clear;
	    next;
	}

	my $fp;
	eval {
	    $fp = Net::SSLeay::X509_get_fingerprint($cert, 'sha256');
	};
	$err = $@;
	if ($err || !defined($fp) || $fp eq '') {
	    &$clear_old() if $clear;
	    next;
	}

	my $old_fp = $cert_cache_nodes->{$node};
	$cert_cache_fingerprints->{$fp} = 1;
	$cert_cache_nodes->{$node} = $fp;

	if (defined($old_fp) && $fp ne $old_fp) {
	    delete $cert_cache_fingerprints->{$old_fp};
	}
    }
}

# load and cache cert fingerprint once
sub initialize_cert_cache {
    my ($node) = @_;

    update_cert_cache($node)
	if defined($node) && !defined($cert_cache_nodes->{$node});
}

sub check_cert_fingerprint {
    my ($cert) = @_;

    # clear cache every 30 minutes at least
    update_cert_cache(undef, 1) if time() - $cert_cache_timestamp >= 60*30;

    # get fingerprint of server certificate
    my $fp;
    eval {
	$fp = Net::SSLeay::X509_get_fingerprint($cert, 'sha256');
    };
    return 0 if $@ || !defined($fp) || $fp eq ''; # error

    my $check = sub {
	for my $expected (keys %$cert_cache_fingerprints) {
	    return 1 if $fp eq $expected;
	}
	return 0;
    };

    return 1 if &$check();

    # clear cache and retry at most once every minute
    if (time() - $cert_cache_timestamp >= 60) {
	syslog ('info', "Could not verify remote node certificate '$fp' with list of pinned certificates, refreshing cache");
	update_cert_cache();
	return &$check();
    }

    return 0;
}

# bash completion helpers

sub complete_next_vmid {

    my $vmlist = get_vmlist() || {};
    my $idlist = $vmlist->{ids} || {};

    for (my $i = 100; $i < 10000; $i++) {
	return [$i] if !defined($idlist->{$i});
    }

    return [];
}

sub complete_vmid {

    my $vmlist = get_vmlist();
    my $ids = $vmlist->{ids} || {};

    return [ keys %$ids ];
}

sub complete_local_vmid {

    my $vmlist = get_vmlist();
    my $ids = $vmlist->{ids} || {};

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

    my $res = [];
    foreach my $vmid (keys %$ids) {
	my $d = $ids->{$vmid};
	next if !$d->{node} || $d->{node} ne $nodename;
	push @$res, $vmid;
    }

    return $res;
}

sub complete_migration_target {

    my $res = [];

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

    my $nodelist = get_nodelist();
    foreach my $node (@$nodelist) {
	next if $node eq $nodename;
	push @$res, $node;
    }

    return $res;
}

sub get_ssh_info {
    my ($node, $network_cidr) = @_;

    my $ip;
    if (defined($network_cidr)) {
	# Use mtunnel via to get the remote node's ip inside $network_cidr.
	# This goes over the regular network (iow. uses get_ssh_info() with
	# $network_cidr undefined.
	# FIXME: Use the REST API client for this after creating an API entry
	# for get_migration_ip.
	my $default_remote = get_ssh_info($node, undef);
	my $default_ssh = ssh_info_to_command($default_remote);
	my $cmd =[@$default_ssh, 'pvecm', 'mtunnel',
	    '-migration_network', $network_cidr,
	    '-get_migration_ip'
	];
	PVE::Tools::run_command($cmd, outfunc => sub {
	    my ($line) = @_;
	    chomp $line;
	    die "internal error: unexpected output from mtunnel\n"
		if defined($ip);
	    if ($line =~ /^ip: '(.*)'$/) {
		$ip = $1;
	    } else {
		die "internal error: bad output from mtunnel\n"
		    if defined($ip);
	    }
	});
	die "failed to get ip for node '$node' in network '$network_cidr'\n"
	    if !defined($ip);
    } else {
	$ip = remote_node_ip($node);
    }
 
    return {
	ip => $ip,
	name => $node
    };
}

sub ssh_info_to_command {
    my ($info, @extra_options) = @_;
    return [
	'/usr/bin/ssh',
	'-o', 'BatchMode=yes',
	'-o', 'HostKeyAlias='.$info->{name},
	@extra_options,
	"root\@$info->{ip}"
    ];
}

1;