use Time::HiRes qw (gettimeofday);
+my $LXC_CONFIG_PATH = '/usr/share/lxc/config';
+
my $nodename = PVE::INotify::nodename();
my $cpuinfo= PVE::ProcFSTools::read_cpuinfo();
return wantarray ? ($v1, $v2) : $v1;
}
+# Currently we do not need to create seccomp profile 'files' as the only
+# choice our configuration actually allows is "with or without keyctl()",
+# so we distinguish between using lxc's "default" seccomp profile and our
+# added pve-userns.seccomp file.
+#
+# This returns a configuration line added to the raw lxc config.
+sub make_seccomp_config {
+ my ($conf, $unprivileged, $features) = @_;
+ # User-configured profile has precedence, note that the user's entry would
+ # be written 'after' this line anyway...
+ if (PVE::LXC::Config->has_lxc_entry($conf, 'lxc.seccomp.profile')) {
+ # Warn the user if this conflicts with a feature:
+ if ($features->{keyctl}) {
+ warn "explicitly configured lxc.seccomp.profile overrides the following settings: features:keyctl\n";
+ }
+ return '';
+ }
+
+ # Privileged containers keep using the default (which is already part of
+ # the files included via lxc.include, so we don't need to write it out,
+ # that way it stays admin-configurable via /usr/share/lxc/config/... as
+ # well)
+ return '' if !$unprivileged;
+
+ # Unprivileged containers will get keyctl() disabled by default as a
+ # workaround for systemd-networkd behavior. But we have an option to
+ # explicitly enable it:
+ return '' if $features->{keyctl};
+
+ # Finally we're in an unprivileged container without `keyctl` set
+ # explicitly. We have a file prepared for this:
+ return "lxc.seccomp.profile = $LXC_CONFIG_PATH/pve-userns.seccomp\n";
+}
+
+# Since lxc-3.0.2 we can have lxc generate a profile for the container
+# automatically. The default should be equivalent to the old
+# `lxc-container-default-cgns` profile.
+#
+# Additionally this also added `lxc.apparmor.raw` which can be used to inject
+# additional lines into the profile. We can use that to allow mounting specific
+# file systems.
+sub make_apparmor_config {
+ my ($conf, $unprivileged, $features) = @_;
+
+ # user-configured profile has precedence, but first we go through our own
+ # code to figure out whether we should warn the user:
+
+ my $raw = "lxc.apparmor.profile = generated\n";
+ my @profile_uses;
+
+ # There's lxc.apparmor.allow_nesting now, which will add the necessary
+ # apparmor lines, create an apparmor namespace for the container, but also
+ # adds proc and sysfs mounts to /dev/.lxc/{proc,sys}. These do not have
+ # lxcfs mounted over them, because that would prevent the container from
+ # mounting new instances of them for nested containers.
+ if ($features->{nesting}) {
+ push @profile_uses, 'features:nesting';
+ $raw .= "lxc.apparmor.allow_nesting = 1\n"
+ } else {
+ # In the default profile in /etc/apparmor.d we patch this in because
+ # otherwise a container can for example run `chown` on /sys, breaking
+ # access to it for non-CAP_DAC_OVERRIDE tools on the host:
+ $raw .= "lxc.apparmor.raw = deny mount -> /proc/,\n";
+ $raw .= "lxc.apparmor.raw = deny mount -> /sys/,\n";
+ # Preferably we could use the 'remount' flag but this does not sit well
+ # with apparmor_parser currently:
+ # mount options=(rw, nosuid, nodev, noexec, remount) -> /sys/,
+ }
+
+ if (my $mount = $features->{mount}) {
+ push @profile_uses, 'features:mount';
+ foreach my $fs (PVE::Tools::split_list($mount)) {
+ $raw .= "lxc.apparmor.raw = mount fstype=$fs,\n";
+ }
+ }
+
+ # More to come?
+
+ if (PVE::LXC::Config->has_lxc_entry($conf, 'lxc.apparmor.profile')) {
+ if (length(my $used = join(', ', @profile_uses))) {
+ warn "explicitly configured lxc.apparmor.profile overrides the following settings: $used\n";
+ }
+ return '';
+ }
+
+ return $raw;
+}
+
sub update_lxc_config {
my ($vmid, $conf) = @_;
die "missing 'arch' - internal error" if !$conf->{arch};
$raw .= "lxc.arch = $conf->{arch}\n";
- my $unprivileged = $conf->{unprivileged};
- my $custom_idmap = grep { $_->[0] eq 'lxc.idmap' } @{$conf->{lxc}};
+ my $custom_idmap = PVE::LXC::Config->has_lxc_entry($conf, 'lxc.idmap');
+ my $unprivileged = $conf->{unprivileged} || $custom_idmap;
my $ostype = $conf->{ostype} || die "missing 'ostype' - internal error";
my $inc = "$cfgpath/$ostype.common.conf";
$inc ="$cfgpath/common.conf" if !-f $inc;
$raw .= "lxc.include = $inc\n";
- if ($unprivileged || $custom_idmap) {
+ if ($unprivileged) {
$inc = "$cfgpath/$ostype.userns.conf";
$inc = "$cfgpath/userns.conf" if !-f $inc;
$raw .= "lxc.include = $inc\n";
- $raw .= "lxc.seccomp.profile = $cfgpath/pve-userns.seccomp\n";
}
+ my $features = PVE::LXC::Config->parse_features($conf->{features});
+
+ $raw .= make_seccomp_config($conf, $unprivileged, $features);
+ $raw .= make_apparmor_config($conf, $unprivileged, $features);
+
# WARNING: DO NOT REMOVE this without making sure that loop device nodes
# cannot be exposed to the container with r/w access (cgroup perms).
# When this is enabled mounts will still remain in the monitor's namespace
} elsif ($opt =~ m/^net\d+$/ || $opt eq 'nameserver' ||
$opt eq 'searchdomain' || $opt eq 'hostname') {
$rpcenv->check_vm_perm($authuser, $vmid, $pool, ['VM.Config.Network']);
+ } elsif ($opt eq 'features') {
+ # For now this is restricted to root@pam
+ raise_perm_exc("changing feature flags is only allowed for root\@pam");
} else {
$rpcenv->check_vm_perm($authuser, $vmid, $pool, ['VM.Config.Options']);
}
projects / pve-container.git / blobdiff