diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix
index 28f536056bf1..40904ef0c175 100644
--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -200,6 +200,7 @@
./security/rtkit.nix
./security/wrappers/default.nix
./security/sudo.nix
+ ./security/doas.nix
./security/systemd-confinement.nix
./security/tpm2.nix
./services/admin/oxidized.nix
diff --git a/nixos/modules/security/doas.nix b/nixos/modules/security/doas.nix
new file mode 100644
index 000000000000..1991a58db60d
--- /dev/null
+++ b/nixos/modules/security/doas.nix
@@ -0,0 +1,274 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+let
+ cfg = config.security.doas;
+
+ inherit (pkgs) doas;
+
+ mkUsrString = user: toString user;
+
+ mkGrpString = group: ":${toString group}";
+
+ mkOpts = rule: concatStringsSep " " [
+ (optionalString rule.noPass "nopass")
+ (optionalString rule.persist "persist")
+ (optionalString rule.keepEnv "keepenv")
+ "setenv { SSH_AUTH_SOCK ${concatStringsSep " " rule.setEnv} }"
+ ];
+
+ mkArgs = rule:
+ if (isNull rule.args) then ""
+ else if (length rule.args == 0) then "args"
+ else "args ${concatStringsSep " " rule.args}";
+
+ mkRule = rule:
+ let
+ opts = mkOpts rule;
+
+ as = optionalString (!isNull rule.runAs) "as ${rule.runAs}";
+
+ cmd = optionalString (!isNull rule.cmd) "cmd ${rule.cmd}";
+
+ args = mkArgs rule;
+ in
+ optionals (length cfg.extraRules > 0) [
+ (
+ optionalString (length rule.users > 0)
+ (map (usr: "permit ${opts} ${mkUsrString usr} ${as} ${cmd} ${args}") rule.users)
+ )
+ (
+ optionalString (length rule.groups > 0)
+ (map (grp: "permit ${opts} ${mkGrpString grp} ${as} ${cmd} ${args}") rule.groups)
+ )
+ ];
+in
+{
+
+ ###### interface
+
+ options.security.doas = {
+
+ enable = mkOption {
+ type = with types; bool;
+ default = false;
+ description = ''
+ Whether to enable the doas command, which allows
+ non-root users to execute commands as root.
+ '';
+ };
+
+ wheelNeedsPassword = mkOption {
+ type = with types; bool;
+ default = true;
+ description = ''
+ Whether users of the wheel
group must provide a password to
+ run commands as super user via doas.
+ '';
+ };
+
+ extraRules = mkOption {
+ default = [];
+ description = ''
+ Define specific rules to be set in the
+ /etc/doas.conf file. More specific rules should
+ come after more general ones in order to yield the expected behavior.
+ You can use mkBefore
and/or mkAfter
to ensure
+ this is the case when configuration options are merged.
+ '';
+ example = literalExample ''
+ [
+ # Allow execution of any command by any user in group doas, requiring
+ # a password and keeping any previously-defined environment variables.
+ { groups = [ "doas" ]; noPass = false; keepEnv = true; }
+
+ # Allow execution of "/home/root/secret.sh" by user `backup` OR user
+ # `database` OR any member of the group with GID `1006`, without a
+ # password.
+ { users = [ "backup" "database" ]; groups = [ 1006 ];
+ cmd = "/home/root/secret.sh"; noPass = true; }
+
+ # Allow any member of group `bar` to run `/home/baz/cmd1.sh` as user
+ # `foo` with argument `hello-doas`.
+ { groups = [ "bar" ]; runAs = "foo";
+ cmd = "/home/baz/cmd1.sh"; args = [ "hello-doas" ]; }
+
+ # Allow any member of group `bar` to run `/home/baz/cmd2.sh` as user
+ # `foo` with no arguments.
+ { groups = [ "bar" ]; runAs = "foo";
+ cmd = "/home/baz/cmd2.sh"; args = [ ]; }
+
+ # Allow user `abusers` to execute "nano" and unset the value of
+ # SSH_AUTH_SOCK, override the value of ALPHA to 1, and inherit the
+ # value of BETA from the current environment.
+ { users = [ "abusers" ]; cmd = "nano";
+ setEnv = [ "-SSH_AUTH_SOCK" "ALPHA=1" "BETA" ]; }
+ ]
+ '';
+ type = with types; listOf (
+ submodule {
+ options = {
+
+ noPass = mkOption {
+ type = with types; bool;
+ default = false;
+ description = ''
+ If true
, the user is not required to enter a
+ password.
+ '';
+ };
+
+ persist = mkOption {
+ type = with types; bool;
+ default = false;
+ description = ''
+ If true
, do not ask for a password again for some
+ time after the user successfully authenticates.
+ '';
+ };
+
+ keepEnv = mkOption {
+ type = with types; bool;
+ default = false;
+ description = ''
+ If true
, environment variables other than those
+ listed in
+ doas1
+ are kept when creating the environment for the new process.
+ '';
+ };
+
+ setEnv = mkOption {
+ type = with types; listOf str;
+ default = [];
+ description = ''
+ Keep or set the specified variables. Variables may also be
+ removed with a leading '-' or set using
+ variable=value
. If the first character of
+ value
is a '$', the value to be set is taken from
+ the existing environment variable of the indicated name. This
+ option is processed after the default environment has been
+ created.
+
+ NOTE: All rules have setenv { SSH_AUTH_SOCK }
by
+ default. To prevent SSH_AUTH_SOCK
from being
+ inherited, add "-SSH_AUTH_SOCK"
anywhere in this
+ list.
+ '';
+ };
+
+ users = mkOption {
+ type = with types; listOf (either str int);
+ default = [];
+ description = "The usernames / UIDs this rule should apply for.";
+ };
+
+ groups = mkOption {
+ type = with types; listOf (either str int);
+ default = [];
+ description = "The groups / GIDs this rule should apply for.";
+ };
+
+ runAs = mkOption {
+ type = with types; nullOr str;
+ default = null;
+ description = ''
+ Which user or group the specified command is allowed to run as.
+ When set to null
(the default), all users are
+ allowed.
+
+ A user can be specified using just the username:
+ "foo"
. It is also possible to only allow running as
+ a specific group with ":bar"
.
+ '';
+ };
+
+ cmd = mkOption {
+ type = with types; nullOr str;
+ default = null;
+ description = ''
+ The command the user is allowed to run. When set to
+ null
(the default), all commands are allowed.
+
+ NOTE: It is best practice to specify absolute paths. If a
+ relative path is specified, only a restricted PATH will be
+ searched.
+ '';
+ };
+
+ args = mkOption {
+ type = with types; nullOr (listOf str);
+ default = null;
+ description = ''
+ Arguments that must be provided to the command. When set to
+ []
, the command must be run without any arguments.
+ '';
+ };
+ };
+ }
+ );
+ };
+
+ extraConfig = mkOption {
+ type = with types; lines;
+ default = "";
+ description = ''
+ Extra configuration text appended to doas.conf.
+ '';
+ };
+ };
+
+
+ ###### implementation
+
+ config = mkIf cfg.enable {
+
+ security.doas.extraRules = [
+ {
+ groups = [ "wheel" ];
+ noPass = !cfg.wheelNeedsPassword;
+ }
+ ];
+
+ security.wrappers = {
+ doas.source = "${doas}/bin/doas";
+ };
+
+ environment.systemPackages = [
+ doas
+ ];
+
+ security.pam.services.doas = {
+ allowNullPassword = true;
+ sshAgentAuth = true;
+ };
+
+ environment.etc."doas.conf" = {
+ source = pkgs.runCommand "doas-conf"
+ {
+ src = pkgs.writeText "doas-conf-in" ''
+ # To modify this file, set the NixOS options
+ # `security.doas.extraRules` or `security.doas.extraConfig`. To
+ # completely replace the contents of this file, use
+ # `environment.etc."doas.conf"`.
+
+ # "root" is allowed to do anything.
+ permit nopass keepenv root
+
+ # extraRules
+ ${concatStringsSep "\n" (lists.flatten (map mkRule cfg.extraRules))}
+
+ # extraConfig
+ ${cfg.extraConfig}
+ '';
+ preferLocalBuild = true;
+ }
+ # Make sure that the doas.conf file is syntactically valid.
+ "${pkgs.buildPackages.doas}/bin/doas -C $src && cp $src $out";
+ mode = "0440";
+ };
+
+ };
+
+ meta.maintainers = with maintainers; [ cole-h ];
+}
diff --git a/nixos/tests/all-tests.nix b/nixos/tests/all-tests.nix
index ebb0dfef15ac..b8ff4647b9f4 100644
--- a/nixos/tests/all-tests.nix
+++ b/nixos/tests/all-tests.nix
@@ -69,6 +69,7 @@ in
deluge = handleTest ./deluge.nix {};
dhparams = handleTest ./dhparams.nix {};
dnscrypt-proxy2 = handleTestOn ["x86_64-linux"] ./dnscrypt-proxy2.nix {};
+ doas = handleTest ./doas.nix {};
docker = handleTestOn ["x86_64-linux"] ./docker.nix {};
oci-containers = handleTestOn ["x86_64-linux"] ./oci-containers.nix {};
docker-edge = handleTestOn ["x86_64-linux"] ./docker-edge.nix {};
diff --git a/nixos/tests/doas.nix b/nixos/tests/doas.nix
new file mode 100644
index 000000000000..9c0a4bdc7563
--- /dev/null
+++ b/nixos/tests/doas.nix
@@ -0,0 +1,83 @@
+# Some tests to ensure doas is working properly.
+import ./make-test-python.nix (
+ { lib, ... }: {
+ name = "doas";
+ meta = with lib.maintainers; {
+ maintainers = [ cole-h ];
+ };
+
+ machine =
+ { ... }:
+ {
+ users.groups = { foobar = {}; barfoo = {}; baz = { gid = 1337; }; };
+ users.users = {
+ test0 = { isNormalUser = true; extraGroups = [ "wheel" ]; };
+ test1 = { isNormalUser = true; };
+ test2 = { isNormalUser = true; extraGroups = [ "foobar" ]; };
+ test3 = { isNormalUser = true; extraGroups = [ "barfoo" ]; };
+ test4 = { isNormalUser = true; extraGroups = [ "baz" ]; };
+ test5 = { isNormalUser = true; };
+ test6 = { isNormalUser = true; };
+ test7 = { isNormalUser = true; };
+ };
+
+ security.doas = {
+ enable = true;
+ wheelNeedsPassword = false;
+
+ extraRules = [
+ { users = [ "test1" ]; groups = [ "foobar" ]; }
+ { users = [ "test2" ]; noPass = true; setEnv = [ "CORRECT" "HORSE=BATTERY" ]; }
+ { groups = [ "barfoo" 1337 ]; noPass = true; }
+ { users = [ "test5" ]; noPass = true; keepEnv = true; runAs = "test1"; }
+ { users = [ "test6" ]; noPass = true; keepEnv = true; setEnv = [ "-STAPLE" ]; }
+ { users = [ "test7" ]; noPass = true; setEnv = [ "-SSH_AUTH_SOCK" ]; }
+ ];
+ };
+ };
+
+ testScript = ''
+ with subtest("users in wheel group should have passwordless doas"):
+ machine.succeed('su - test0 -c "doas -u root true"')
+
+ with subtest("test1 user should not be able to use doas without password"):
+ machine.fail('su - test1 -c "doas -n -u root true"')
+
+ with subtest("test2 user should be able to keep some env"):
+ if "CORRECT=1" not in machine.succeed('su - test2 -c "CORRECT=1 doas env"'):
+ raise Exception("failed to keep CORRECT")
+
+ if "HORSE=BATTERY" not in machine.succeed('su - test2 -c "doas env"'):
+ raise Exception("failed to setenv HORSE=BATTERY")
+
+ with subtest("users in group 'barfoo' shouldn't require password"):
+ machine.succeed("doas -u test3 doas -n -u root true")
+
+ with subtest("users in group 'baz' (GID 1337) shouldn't require password"):
+ machine.succeed("doas -u test4 doas -n -u root echo true")
+
+ with subtest("test5 user should be able to run commands under test1"):
+ machine.succeed("doas -u test5 doas -n -u test1 true")
+
+ with subtest("test5 user should not be able to run commands under root"):
+ machine.fail("doas -u test5 doas -n -u root true")
+
+ with subtest("test6 user should be able to keepenv"):
+ envs = ["BATTERY=HORSE", "CORRECT=false"]
+ out = machine.succeed(
+ 'su - test6 -c "BATTERY=HORSE CORRECT=false STAPLE=Tr0ub4dor doas env"'
+ )
+
+ if not all(env in out for env in envs):
+ raise Exception("failed to keep BATTERY or CORRECT")
+ if "STAPLE=Tr0ub4dor" in out:
+ raise Exception("failed to exclude STAPLE")
+
+ with subtest("test7 should not have access to SSH_AUTH_SOCK"):
+ if "SSH_AUTH_SOCK=HOLEY" in machine.succeed(
+ 'su - test7 -c "SSH_AUTH_SOCK=HOLEY doas env"'
+ ):
+ raise Exception("failed to exclude SSH_AUTH_SOCK")
+ '';
+ }
+)