nixos/matrix-synapse: protect created files

Enforce UMask on the systemd unit to restrict the permissions of files
created. Especially the homeserver signing key should not be world
readable, and media is served through synapse itself, so no other user
needs access to these files.

Use a prestart chmod to fixup the permissions on the signing key.
This commit is contained in:
Martin Weinelt 2021-05-22 00:47:54 +02:00
parent a420acab1e
commit 79e675444c
No known key found for this signature in database
GPG key ID: 87C1E9888F856759

View file

@ -699,12 +699,12 @@ in {
];
users.users.matrix-synapse = {
group = "matrix-synapse";
home = cfg.dataDir;
createHome = true;
shell = "${pkgs.bash}/bin/bash";
uid = config.ids.uids.matrix-synapse;
};
group = "matrix-synapse";
home = cfg.dataDir;
createHome = true;
shell = "${pkgs.bash}/bin/bash";
uid = config.ids.uids.matrix-synapse;
};
users.groups.matrix-synapse = {
gid = config.ids.gids.matrix-synapse;
@ -726,6 +726,10 @@ in {
User = "matrix-synapse";
Group = "matrix-synapse";
WorkingDirectory = cfg.dataDir;
ExecStartPre = [ ("+" + (pkgs.writeShellScript "matrix-synapse-fix-permissions" ''
chown matrix-synapse:matrix-synapse ${cfg.dataDir}/homeserver.signing.key
chmod 0600 ${cfg.dataDir}/homeserver.signing.key
'')) ];
ExecStart = ''
${cfg.package}/bin/homeserver \
${ concatMapStringsSep "\n " (x: "--config-path ${x} \\") ([ configFile ] ++ cfg.extraConfigFiles) }
@ -733,6 +737,7 @@ in {
'';
ExecReload = "${pkgs.util-linux}/bin/kill -HUP $MAINPID";
Restart = "on-failure";
UMask = "0077";
};
};
};