Merge pull request #253876 from nbraud/nixos/sudo-rs

nixos/doc/manual/release-notes/rl-2311.section.md

@@ -10,6 +10,16 @@
 
 - The `nixos-rebuild` command has been given a `list-generations` subcommand. See `man nixos-rebuild` for more details.
 
+- [`sudo-rs`], a reimplementation of `sudo` in Rust, is now supported.
+  Switching to it (via `security.sudo.package = pkgs.sudo-rs;`) introduces
+  slight changes in default behaviour, due to `sudo-rs`' current limitations:
+  - terminfo-related environment variables aren't preserved for `root` and `wheel`;
+  - `root` and `wheel` are not given the ability to set (or preserve)
+    arbitrary environment variables.
+
+[`sudo-rs`]: https://github.com/memorysafety/sudo-rs/
+
+
 ## New Services {#sec-release-23.11-new-services}
 
 - [MCHPRS](https://github.com/MCHPR/MCHPRS), a multithreaded Minecraft server built for redstone. Available as [services.mchprs](#opt-services.mchprs.enable).
@@ -202,6 +212,12 @@
 
 - Package `pash` was removed due to being archived upstream. Use `powershell` as an alternative.
 
+- `security.sudo.extraRules` now includes `root`'s default rule, with ordering
+  priority 400. This is functionally identical for users not specifying rule
+  order, or relying on `mkBefore` and `mkAfter`, but may impact users calling
+  `mkOrder n` with n ≤ 400.
+
+
 ## Other Notable Changes {#sec-release-23.11-notable-changes}
 
 - The Cinnamon module now enables XDG desktop integration by default. If you are experiencing collisions related to xdg-desktop-portal-gtk you can safely remove `xdg.portal.extraPortals = [ pkgs.xdg-desktop-portal-gtk ];` from your NixOS configuration.
@@ -284,6 +300,13 @@ The module update takes care of the new config syntax and the data itself (user
 
 - New `boot.bcache.enable` (default enabled) allows completely removing `bcache` mount support.
 
+- `security.sudo` now provides two extra options, that do not change the
+  module's default behaviour:
+  - `defaultOptions` controls the options used for the default rules;
+  - `keepTerminfo` controls whether `TERMINFO` and `TERMINFO_DIRS` are preserved
+    for `root` and the `wheel` group.
+
+
 ## Nixpkgs internals {#sec-release-23.11-nixpkgs-internals}
 
 - The use of `sourceRoot = "source";`, `sourceRoot = "source/subdir";`, and similar lines in package derivations using the default `unpackPhase` is deprecated as it requires `unpackPhase` to always produce a directory named "source". Use `sourceRoot = src.name`, `sourceRoot = "${src.name}/subdir";`, or `setSourceRoot = "sourceRoot=$(echo */subdir)";` or similar instead.

nixos/lib/test-driver/test_driver/machine.py

@@ -582,9 +582,7 @@ class Machine:
 
         # While sh is bash on NixOS, this is not the case for every distro.
         # We explicitly call bash here to allow for the driver to boot other distros as well.
-        out_command = (
-            f"{timeout_str} bash -c {shlex.quote(command)} | (base64 -w 0; echo)\n"
-        )
+        out_command = f"{timeout_str} bash -c {shlex.quote(command)} 2>/dev/null | (base64 -w 0; echo)\n"
 
         assert self.shell
         self.shell.send(out_command.encode())

nixos/modules/config/terminfo.nix

@@ -6,12 +6,26 @@ with lib;
 
 {
 
-  options.environment.enableAllTerminfo = with lib; mkOption {
-    default = false;
-    type = types.bool;
-    description = lib.mdDoc ''
-      Whether to install all terminfo outputs
-    '';
+  options = with lib; {
+    environment.enableAllTerminfo = mkOption {
+      default = false;
+      type = types.bool;
+      description = lib.mdDoc ''
+        Whether to install all terminfo outputs
+      '';
+    };
+
+    security.sudo.keepTerminfo = mkOption {
+      default = config.security.sudo.package.pname != "sudo-rs";
+      defaultText = literalMD ''
+        `true` unless using `sudo-rs`
+      '';
+      type = types.bool;
+      description = lib.mdDoc ''
+        Whether to preserve the `TERMINFO` and `TERMINFO_DIRS`
+        environment variables, for `root` and the `wheel` group.
+      '';
+    };
   };
 
   config = {
@@ -54,7 +68,7 @@ with lib;
       export TERM=$TERM
     '';
 
-    security.sudo.extraConfig = ''
+    security.sudo.extraConfig = mkIf config.security.sudo.keepTerminfo ''
 
       # Keep terminfo database for root and %wheel.
       Defaults:root,%wheel env_keep+=TERMINFO_DIRS

nixos/modules/security/sudo.nix

@@ -4,9 +4,16 @@ with lib;
 
 let
 
+  inherit (pkgs) sudo sudo-rs;
+
   cfg = config.security.sudo;
 
-  inherit (pkgs) sudo;
+  enableSSHAgentAuth =
+    with config.security;
+    pam.enableSSHAgentAuth && pam.sudo.sshAgentAuth;
+
+  usingMillersSudo = cfg.package.pname == sudo.pname;
+  usingSudoRs = cfg.package.pname == sudo-rs.pname;
 
   toUserString = user: if (isInt user) then "#${toString user}" else "${user}";
   toGroupString = group: if (isInt group) then "%#${toString group}" else "%${group}";
@@ -30,41 +37,51 @@ in
 
   ###### interface
 
-  options = {
+  options.security.sudo = {
 
-    security.sudo.enable = mkOption {
-      type = types.bool;
-      default = true;
-      description =
-        lib.mdDoc ''
-          Whether to enable the {command}`sudo` command, which
-          allows non-root users to execute commands as root.
-        '';
+    defaultOptions = mkOption {
+      type = with types; listOf str;
+      default = optional usingMillersSudo "SETENV";
+      defaultText = literalMD ''
+        `[ "SETENV" ]` if using the default `sudo` implementation
+      '';
+      description = mdDoc ''
+        Options used for the default rules, granting `root` and the
+        `wheel` group permission to run any command as any user.
+      '';
     };
 
-    security.sudo.package = mkOption {
+    enable = mkOption {
+      type = types.bool;
+      default = true;
+      description = mdDoc ''
+        Whether to enable the {command}`sudo` command, which
+        allows non-root users to execute commands as root.
+      '';
+    };
+
+    package = mkOption {
       type = types.package;
       default = pkgs.sudo;
       defaultText = literalExpression "pkgs.sudo";
-      description = lib.mdDoc ''
+      description = mdDoc ''
         Which package to use for `sudo`.
       '';
     };
 
-    security.sudo.wheelNeedsPassword = mkOption {
+    wheelNeedsPassword = mkOption {
       type = types.bool;
       default = true;
-      description =
-        lib.mdDoc ''
-          Whether users of the `wheel` group must
-          provide a password to run commands as super user via {command}`sudo`.
-        '';
+      description = mdDoc ''
+        Whether users of the `wheel` group must
+        provide a password to run commands as super user via {command}`sudo`.
+      '';
       };
 
-    security.sudo.execWheelOnly = mkOption {
+    execWheelOnly = mkOption {
       type = types.bool;
       default = false;
-      description = lib.mdDoc ''
+      description = mdDoc ''
         Only allow members of the `wheel` group to execute sudo by
         setting the executable's permissions accordingly.
         This prevents users that are not members of `wheel` from
@@ -72,19 +89,18 @@ in
       '';
     };
 
-    security.sudo.configFile = mkOption {
+    configFile = mkOption {
       type = types.lines;
       # Note: if syntax errors are detected in this file, the NixOS
       # configuration will fail to build.
-      description =
-        lib.mdDoc ''
-          This string contains the contents of the
-          {file}`sudoers` file.
-        '';
+      description = mdDoc ''
+        This string contains the contents of the
+        {file}`sudoers` file.
+      '';
     };
 
-    security.sudo.extraRules = mkOption {
-      description = lib.mdDoc ''
+    extraRules = mkOption {
+      description = mdDoc ''
         Define specific rules to be in the {file}`sudoers` file.
         More specific rules should come after more general ones in order to
         yield the expected behavior. You can use mkBefore/mkAfter to ensure
@@ -114,7 +130,7 @@ in
         options = {
           users = mkOption {
             type = with types; listOf (either str int);
-            description = lib.mdDoc ''
+            description = mdDoc ''
               The usernames / UIDs this rule should apply for.
             '';
             default = [];
@@ -122,7 +138,7 @@ in
 
           groups = mkOption {
             type = with types; listOf (either str int);
-            description = lib.mdDoc ''
+            description = mdDoc ''
               The groups / GIDs this rule should apply for.
             '';
             default = [];
@@ -131,7 +147,7 @@ in
           host = mkOption {
             type = types.str;
             default = "ALL";
-            description = lib.mdDoc ''
+            description = mdDoc ''
               For what host this rule should apply.
             '';
           };
@@ -139,7 +155,7 @@ in
           runAs = mkOption {
             type = with types; str;
             default = "ALL:ALL";
-            description = lib.mdDoc ''
+            description = mdDoc ''
               Under which user/group the specified command is allowed to run.
 
               A user can be specified using just the username: `"foo"`.
@@ -149,7 +165,7 @@ in
           };
 
           commands = mkOption {
-            description = lib.mdDoc ''
+            description = mdDoc ''
               The commands for which the rule should apply.
             '';
             type = with types; listOf (either str (submodule {
@@ -157,7 +173,7 @@ in
               options = {
                 command = mkOption {
                   type = with types; str;
-                  description = lib.mdDoc ''
+                  description = mdDoc ''
                     A command being either just a path to a binary to allow any arguments,
                     the full command with arguments pre-set or with `""` used as the argument,
                     not allowing arguments to the command at all.
@@ -166,7 +182,7 @@ in
 
                 options = mkOption {
                   type = with types; listOf (enum [ "NOPASSWD" "PASSWD" "NOEXEC" "EXEC" "SETENV" "NOSETENV" "LOG_INPUT" "NOLOG_INPUT" "LOG_OUTPUT" "NOLOG_OUTPUT" ]);
-                  description = lib.mdDoc ''
+                  description = mdDoc ''
                     Options for running the command. Refer to the [sudo manual](https://www.sudo.ws/man/1.7.10/sudoers.man.html).
                   '';
                   default = [];
@@ -179,10 +195,10 @@ in
       });
     };
 
-    security.sudo.extraConfig = mkOption {
+    extraConfig = mkOption {
       type = types.lines;
       default = "";
-      description = lib.mdDoc ''
+      description = mdDoc ''
         Extra configuration text appended to {file}`sudoers`.
       '';
     };
@@ -192,44 +208,52 @@ in
   ###### implementation
 
   config = mkIf cfg.enable {
-    assertions = [
-      { assertion = cfg.package.pname != "sudo-rs";
-        message = "The NixOS `sudo` module does not work with `sudo-rs` yet."; }
-    ];
+    security.sudo.extraRules =
+      let
+        defaultRule = { users ? [], groups ? [], opts ? [] }: [ {
+          inherit users groups;
+          commands = [ {
+            command = "ALL";
+            options = opts ++ cfg.defaultOptions;
+          } ];
+        } ];
+      in mkMerge [
+        # This is ordered before users' `mkBefore` rules,
+        # so as not to introduce unexpected changes.
+        (mkOrder 400 (defaultRule { users = [ "root" ]; }))
 
-    # We `mkOrder 600` so that the default rule shows up first, but there is
-    # still enough room for a user to `mkBefore` it.
-    security.sudo.extraRules = mkOrder 600 [
-      { groups = [ "wheel" ];
-        commands = [ { command = "ALL"; options = (if cfg.wheelNeedsPassword then [ "SETENV" ] else [ "NOPASSWD" "SETENV" ]); } ];
-      }
-    ];
+        # This is ordered to show before (most) other rules, but
+        # late-enough for a user to `mkBefore` it.
+        (mkOrder 600 (defaultRule {
+          groups = [ "wheel" ];
+          opts = (optional (!cfg.wheelNeedsPassword) "NOPASSWD");
+        }))
+      ];
 
-    security.sudo.configFile =
+    security.sudo.configFile = concatStringsSep "\n" (filter (s: s != "") [
       ''
         # Don't edit this file. Set the NixOS options ‘security.sudo.configFile’
         # or ‘security.sudo.extraRules’ instead.
-
+      ''
+      (optionalString enableSSHAgentAuth ''
         # Keep SSH_AUTH_SOCK so that pam_ssh_agent_auth.so can do its magic.
         Defaults env_keep+=SSH_AUTH_SOCK
-
-        # "root" is allowed to do anything.
-        root        ALL=(ALL:ALL) SETENV: ALL
-
-        # extraRules
-        ${concatStringsSep "\n" (
-          lists.flatten (
-            map (
-              rule: optionals (length rule.commands != 0) [
-                (map (user: "${toUserString user}	${rule.host}=(${rule.runAs})	${toCommandsString rule.commands}") rule.users)
-                (map (group: "${toGroupString group}	${rule.host}=(${rule.runAs})	${toCommandsString rule.commands}") rule.groups)
-              ]
-            ) cfg.extraRules
-          )
-        )}
-
+      '')
+      (concatStringsSep "\n" (
+        lists.flatten (
+          map (
+            rule: optionals (length rule.commands != 0) [
+              (map (user: "${toUserString user}	${rule.host}=(${rule.runAs})	${toCommandsString rule.commands}") rule.users)
+              (map (group: "${toGroupString group}	${rule.host}=(${rule.runAs})	${toCommandsString rule.commands}") rule.groups)
+            ]
+          ) cfg.extraRules
+        )
+      ) + "\n")
+      (optionalString (cfg.extraConfig != "") ''
+        # extraConfig
         ${cfg.extraConfig}
-      '';
+      '')
+    ]);
 
     security.wrappers = let
       owner = "root";
@@ -241,7 +265,8 @@ in
         source = "${cfg.package.out}/bin/sudo";
         inherit owner group setuid permissions;
       };
-      sudoedit = {
+      # sudo-rs does not yet ship a sudoedit (as of v0.2.0)
+      sudoedit = mkIf usingMillersSudo {
         source = "${cfg.package.out}/bin/sudoedit";
         inherit owner group setuid permissions;
       };
@@ -250,6 +275,8 @@ in
     environment.systemPackages = [ sudo ];
 
     security.pam.services.sudo = { sshAgentAuth = true; usshAuth = true; };
+    security.pam.services.sudo-i = mkIf usingSudoRs
+      { sshAgentAuth = true; usshAuth = true; };
 
     environment.etc.sudoers =
       { source =
@@ -258,12 +285,12 @@ in
             src = pkgs.writeText "sudoers-in" cfg.configFile;
             preferLocalBuild = true;
           }
-          # Make sure that the sudoers file is syntactically valid.
-          # (currently disabled - NIXOS-66)
-          "${pkgs.buildPackages.sudo}/sbin/visudo -f $src -c && cp $src $out";
+          "${cfg.package}/bin/visudo -f $src -c && cp $src $out";
         mode = "0440";
       };
 
   };
 
+  meta.maintainers = [ lib.maintainers.nicoo ];
+
 }

nixos/tests/all-tests.nix

@@ -741,6 +741,7 @@ in {
   strongswan-swanctl = handleTest ./strongswan-swanctl.nix {};
   stunnel = handleTest ./stunnel.nix {};
   sudo = handleTest ./sudo.nix {};
+  sudo-rs = handleTest ./sudo-rs.nix {};
   swap-file-btrfs = handleTest ./swap-file-btrfs.nix {};
   swap-partition = handleTest ./swap-partition.nix {};
   swap-random-encryption = handleTest ./swap-random-encryption.nix {};

nixos/tests/sudo-rs.nix

@@ -0,0 +1,97 @@
+# Some tests to ensure sudo is working properly.
+{ pkgs, sudo-rs, ... }:
+let
+  inherit (pkgs.lib) mkIf optionalString;
+  password = "helloworld";
+in
+  import ./make-test-python.nix ({ lib, pkgs, ...} : {
+    name = "sudo";
+    meta.maintainers = pkgs.sudo-rs.meta.maintainers;
+
+    nodes.machine =
+      { lib, ... }:
+      {
+        environment.systemPackages = [ pkgs.faketty ];
+        users.groups = { foobar = {}; barfoo = {}; baz = { gid = 1337; }; };
+        users.users = {
+          test0 = { isNormalUser = true; extraGroups = [ "wheel" ]; };
+          test1 = { isNormalUser = true; password = password; };
+          test2 = { isNormalUser = true; extraGroups = [ "foobar" ]; password = password; };
+          test3 = { isNormalUser = true; extraGroups = [ "barfoo" ]; };
+          test4 = { isNormalUser = true; extraGroups = [ "baz" ]; };
+          test5 = { isNormalUser = true; };
+        };
+
+        security.sudo = {
+          enable = true;
+          package = sudo-rs;
+          wheelNeedsPassword = false;
+
+          extraRules = [
+            # SUDOERS SYNTAX CHECK (Test whether the module produces a valid output;
+            # errors being detected by the visudo checks.
+
+            # These should not create any entries
+            { users = [ "notest1" ]; commands = [ ]; }
+            { commands = [ { command = "ALL"; options = [ ]; } ]; }
+
+            # Test defining commands with the options syntax, though not setting any options
+            { users = [ "notest2" ]; commands = [ { command = "ALL"; options = [ ]; } ]; }
+
+
+            # CONFIGURATION FOR TEST CASES
+            { users = [ "test1" ]; groups = [ "foobar" ]; commands = [ "ALL" ]; }
+            { groups = [ "barfoo" 1337 ]; commands = [ { command = "ALL"; options = [ "NOPASSWD" ]; } ]; }
+            { users = [ "test5" ]; commands = [ { command = "ALL"; options = [ "NOPASSWD" ]; } ]; runAs = "test1:barfoo"; }
+          ];
+        };
+      };
+
+    nodes.strict = { ... }: {
+      environment.systemPackages = [ pkgs.faketty ];
+      users.users = {
+        admin = { isNormalUser = true; extraGroups = [ "wheel" ]; };
+        noadmin = { isNormalUser = true; };
+      };
+
+      security.sudo = {
+        package = sudo-rs;
+        enable = true;
+        wheelNeedsPassword = false;
+        execWheelOnly = true;
+      };
+    };
+
+    testScript =
+      ''
+        with subtest("users in wheel group should have passwordless sudo"):
+            machine.succeed('faketty -- su - test0 -c "sudo -u root true"')
+
+        with subtest("test1 user should have sudo with password"):
+            machine.succeed('faketty -- su - test1 -c "echo ${password} | sudo -S -u root true"')
+
+        with subtest("test1 user should not be able to use sudo without password"):
+            machine.fail('faketty -- su - test1 -c "sudo -n -u root true"')
+
+        with subtest("users in group 'foobar' should be able to use sudo with password"):
+            machine.succeed('faketty -- su - test2 -c "echo ${password} | sudo -S -u root true"')
+
+        with subtest("users in group 'barfoo' should be able to use sudo without password"):
+            machine.succeed("sudo -u test3 sudo -n -u root true")
+
+        with subtest("users in group 'baz' (GID 1337)"):
+            machine.succeed("sudo -u test4 sudo -n -u root echo true")
+
+        with subtest("test5 user should be able to run commands under test1"):
+            machine.succeed("sudo -u test5 sudo -n -u test1 true")
+
+        with subtest("test5 user should not be able to run commands under root"):
+            machine.fail("sudo -u test5 sudo -n -u root true")
+
+        with subtest("users in wheel should be able to run sudo despite execWheelOnly"):
+            strict.succeed('faketty -- su - admin -c "sudo -u root true"')
+
+        with subtest("non-wheel users should be unable to run sudo thanks to execWheelOnly"):
+            strict.fail('faketty -- su - noadmin -c "sudo --help"')
+      '';;
+  })

pkgs/tools/security/sudo-rs/default.nix

@@ -4,6 +4,7 @@
 , fetchpatch
 , installShellFiles
 , nix-update-script
+, nixosTests
 , pam
 , pandoc
 , rustPlatform
@@ -73,7 +74,10 @@ rustPlatform.buildRustPackage rec {
     "su::context::tests::invalid_shell"
   ];
 
-  passthru.updateScript = nix-update-script { };
+  passthru = {
+    updateScript = nix-update-script { };
+    tests = nixosTests.sudo-rs;
+  };
 
   meta = with lib; {
     description = "A memory safe implementation of sudo and su.";