[pve-devel] [PATCH qemu-server] cloud-init: allow custom network/user data files via snippets

[David Limbeck]

Adds the 'cicustom' option to specify either or both network_data and
user_data options as property strings. Their parameters are files
in a snippets storage (e.g. local:snippets/network.yaml). If one or both
are specified they are used instead of their respective generated
configuration.
This allows the use of completely custom configurations and is also a
possible solution for bug #2038 by specifying a custom user_data file
that contains package_upgrade: false.

Tested with Ubuntu 18.10

Signed-off-by: David Limbeck <d.limbeck at proxmox.com>
---
 PVE/API2/Qemu.pm            |  1 +
 PVE/QemuServer.pm           | 24 ++++++++++++++++++++++++
 PVE/QemuServer/Cloudinit.pm | 37 +++++++++++++++++++++++++++++++++----
 3 files changed, 58 insertions(+), 4 deletions(-)

diff --git a/PVE/API2/Qemu.pm b/PVE/API2/Qemu.pm
index 22f9f6a..49aaa48 100644
--- a/PVE/API2/Qemu.pm
+++ b/PVE/API2/Qemu.pm
@@ -292,6 +292,7 @@ my $diskoptions = {
 };
 
 my $cloudinitoptions = {
+    cicustom => 1,
     cipassword => 1,
     citype => 1,
     ciuser => 1,
diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
index 4a903a6..7c39b97 100644
--- a/PVE/QemuServer.pm
+++ b/PVE/QemuServer.pm
@@ -623,6 +623,24 @@ EODESCR
     },
 };
 
+my $cicustom_fmt = {
+    network_data => {
+	type => 'string',
+	optional => 1,
+	description => 'Specify a custom file containing all network data passed to the VM via cloud-init.',
+	format => 'pve-volume-id',
+	format_description => 'volume',
+    },
+    user_data => {
+	type => 'string',
+	optional => 1,
+	description => 'Specify a custom file containing all user data passed to the VM via cloud-init.',
+	format => 'pve-volume-id',
+	format_description => 'volume',
+    },
+};
+PVE::JSONSchema::register_format('pve-qm-cicustom', $cicustom_fmt);
+
 my $confdesc_cloudinit = {
     citype => {
 	optional => 1,
@@ -640,6 +658,12 @@ my $confdesc_cloudinit = {
 	type => 'string',
 	description => 'cloud-init: Password to assign the user. Using this is generally not recommended. Use ssh keys instead. Also note that older cloud-init versions do not support hashed passwords.',
     },
+    cicustom => {
+	optional => 1,
+	type => 'string',
+	description => 'cloud-init: Specify custom files to replace the automatically generated ones at start.',
+	format => 'pve-qm-cicustom',
+    },
     searchdomain => {
 	optional => 1,
 	type => 'string',
diff --git a/PVE/QemuServer/Cloudinit.pm b/PVE/QemuServer/Cloudinit.pm
index 5be820c..9f36744 100644
--- a/PVE/QemuServer/Cloudinit.pm
+++ b/PVE/QemuServer/Cloudinit.pm
@@ -208,8 +208,9 @@ EOF
 sub generate_configdrive2 {
     my ($conf, $vmid, $drive, $volname, $storeid) = @_;
 
-    my $user_data = cloudinit_userdata($conf, $vmid);
-    my $network_data = configdrive2_network($conf);
+    my ($user_data, $network_data) = get_custom_cloudinit_files($conf);
+    $user_data = cloudinit_userdata($conf, $vmid) if !defined($user_data);
+    $network_data = configdrive2_network($conf) if !defined($network_data);
 
     my $digest_data = $user_data . $network_data;
     my $uuid_str = Digest::SHA::sha1_hex($digest_data);
@@ -378,8 +379,9 @@ sub nocloud_metadata {
 sub generate_nocloud {
     my ($conf, $vmid, $drive, $volname, $storeid) = @_;
 
-    my $user_data = cloudinit_userdata($conf, $vmid);
-    my $network_data = nocloud_network($conf);
+    my ($user_data, $network_data) = get_custom_cloudinit_files($conf);
+    $user_data = cloudinit_userdata($conf, $vmid) if !defined($user_data);
+    $network_data = nocloud_network($conf) if !defined($network_data);
 
     my $digest_data = $user_data . $network_data;
     my $uuid_str = Digest::SHA::sha1_hex($digest_data);
@@ -394,6 +396,33 @@ sub generate_nocloud {
     commit_cloudinit_disk($conf, $vmid, $drive, $volname, $storeid, $files, 'cidata');
 }
 
+sub get_custom_cloudinit_files {
+    my ($conf) = @_;
+
+    my $cicustom = $conf->{cicustom};
+    my $files = $cicustom ? PVE::JSONSchema::parse_property_string('pve-qm-cicustom', $cicustom) : {};
+
+    my $network_data_file = $files->{network_data};
+    my $user_data_file = $files->{user_data};
+
+    my $storage_conf = PVE::Storage::config();
+
+    my $network_data;
+    if ($network_data_file) {
+	my ($full_path, undef, $type) = PVE::Storage::path($storage_conf, $network_data_file);
+	die "$network_data_file is not in the snippets directory\n" if $type ne 'snippets';
+	$network_data = PVE::Tools::file_get_contents($full_path);
+    }
+    my $user_data;
+    if ($user_data_file) {
+	my ($full_path, undef, $type) = PVE::Storage::path($storage_conf, $user_data_file);
+	die "$user_data_file is not in the snippets directory\n" if $type ne 'snippets';
+	$user_data = PVE::Tools::file_get_contents($full_path);
+    }
+
+    return ($user_data, $network_data);
+}
+
 my $cloudinit_methods = {
     configdrive2 => \&generate_configdrive2,
     nocloud => \&generate_nocloud,
-- 
2.11.0