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|
# This module provides configuration for the PAM (Pluggable
# Authentication Modules) system.
{ config, lib, pkgs, ... }:
with lib;
let
parentConfig = config;
pamOpts = { config, name, ... }: let cfg = config; in let config = parentConfig; in {
options = {
name = mkOption {
example = "sshd";
type = types.str;
description = "Name of the PAM service.";
};
unixAuth = mkOption {
default = true;
type = types.bool;
description = ''
Whether users can log in with passwords defined in
<filename>/etc/shadow</filename>.
'';
};
rootOK = mkOption {
default = false;
type = types.bool;
description = ''
If set, root doesn't need to authenticate (e.g. for the
<command>useradd</command> service).
'';
};
u2fAuth = mkOption {
default = config.security.pam.enableU2F;
type = types.bool;
description = ''
If set, users listed in
<filename>~/.config/Yubico/u2f_keys</filename> are able to log in
with the associated U2F key.
'';
};
googleAuthenticator = {
enable = mkOption {
default = false;
type = types.bool;
description = ''
If set, users with enabled Google Authenticator (created
<filename>~/.google_authenticator</filename>) will be required
to provide Google Authenticator token to log in.
'';
};
};
usbAuth = mkOption {
default = config.security.pam.usb.enable;
type = types.bool;
description = ''
If set, users listed in
<filename>/etc/pamusb.conf</filename> are able to log in
with the associated USB key.
'';
};
otpwAuth = mkOption {
default = config.security.pam.enableOTPW;
type = types.bool;
description = ''
If set, the OTPW system will be used (if
<filename>~/.otpw</filename> exists).
'';
};
googleOsLoginAccountVerification = mkOption {
default = false;
type = types.bool;
description = ''
If set, will use the Google OS Login PAM modules
(<literal>pam_oslogin_login</literal>,
<literal>pam_oslogin_admin</literal>) to verify possible OS Login
users and set sudoers configuration accordingly.
This only makes sense to enable for the <literal>sshd</literal> PAM
service.
'';
};
googleOsLoginAuthentication = mkOption {
default = false;
type = types.bool;
description = ''
If set, will use the <literal>pam_oslogin_login</literal>'s user
authentication methods to authenticate users using 2FA.
This only makes sense to enable for the <literal>sshd</literal> PAM
service.
'';
};
fprintAuth = mkOption {
default = config.services.fprintd.enable;
type = types.bool;
description = ''
If set, fingerprint reader will be used (if exists and
your fingerprints are enrolled).
'';
};
oathAuth = mkOption {
default = config.security.pam.oath.enable;
type = types.bool;
description = ''
If set, the OATH Toolkit will be used.
'';
};
sshAgentAuth = mkOption {
default = false;
type = types.bool;
description = ''
If set, the calling user's SSH agent is used to authenticate
against the keys in the calling user's
<filename>~/.ssh/authorized_keys</filename>. This is useful
for <command>sudo</command> on password-less remote systems.
'';
};
startSession = mkOption {
default = false;
type = types.bool;
description = ''
If set, the service will register a new session with
systemd's login manager. For local sessions, this will give
the user access to audio devices, CD-ROM drives. In the
default PolicyKit configuration, it also allows the user to
reboot the system.
'';
};
setEnvironment = mkOption {
type = types.bool;
default = true;
description = ''
Whether the service should set the environment variables
listed in <option>environment.sessionVariables</option>
using <literal>pam_env.so</literal>.
'';
};
setLoginUid = mkOption {
type = types.bool;
description = ''
Set the login uid of the process
(<filename>/proc/self/loginuid</filename>) for auditing
purposes. The login uid is only set by ‘entry points’ like
<command>login</command> and <command>sshd</command>, not by
commands like <command>sudo</command>.
'';
};
forwardXAuth = mkOption {
default = false;
type = types.bool;
description = ''
Whether X authentication keys should be passed from the
calling user to the target user (e.g. for
<command>su</command>)
'';
};
pamMount = mkOption {
default = config.security.pam.mount.enable;
type = types.bool;
description = ''
Enable PAM mount (pam_mount) system to mount fileystems on user login.
'';
};
allowNullPassword = mkOption {
default = false;
type = types.bool;
description = ''
Whether to allow logging into accounts that have no password
set (i.e., have an empty password field in
<filename>/etc/passwd</filename> or
<filename>/etc/group</filename>). This does not enable
logging into disabled accounts (i.e., that have the password
field set to <literal>!</literal>). Note that regardless of
what the pam_unix documentation says, accounts with hashed
empty passwords are always allowed to log in.
'';
};
requireWheel = mkOption {
default = false;
type = types.bool;
description = ''
Whether to permit root access only to members of group wheel.
'';
};
limits = mkOption {
description = ''
Attribute set describing resource limits. Defaults to the
value of <option>security.pam.loginLimits</option>.
'';
};
showMotd = mkOption {
default = false;
type = types.bool;
description = "Whether to show the message of the day.";
};
makeHomeDir = mkOption {
default = false;
type = types.bool;
description = ''
Whether to try to create home directories for users
with <literal>$HOME</literal>s pointing to nonexistent
locations on session login.
'';
};
updateWtmp = mkOption {
default = false;
type = types.bool;
description = "Whether to update <filename>/var/log/wtmp</filename>.";
};
logFailures = mkOption {
default = false;
type = types.bool;
description = "Whether to log authentication failures in <filename>/var/log/faillog</filename>.";
};
enableAppArmor = mkOption {
default = false;
type = types.bool;
description = ''
Enable support for attaching AppArmor profiles at the
user/group level, e.g., as part of a role based access
control scheme.
'';
};
enableKwallet = mkOption {
default = false;
type = types.bool;
description = ''
If enabled, pam_wallet will attempt to automatically unlock the
user's default KDE wallet upon login. If the user has no wallet named
"kdewallet", or the login password does not match their wallet
password, KDE will prompt separately after login.
'';
};
sssdStrictAccess = mkOption {
default = false;
type = types.bool;
description = "enforce sssd access control";
};
enableGnomeKeyring = mkOption {
default = false;
type = types.bool;
description = ''
If enabled, pam_gnome_keyring will attempt to automatically unlock the
user's default Gnome keyring upon login. If the user login password does
not match their keyring password, Gnome Keyring will prompt separately
after login.
'';
};
text = mkOption {
type = types.nullOr types.lines;
description = "Contents of the PAM service file.";
};
};
config = {
name = mkDefault name;
setLoginUid = mkDefault cfg.startSession;
limits = mkDefault config.security.pam.loginLimits;
# !!! TODO: move the LDAP stuff to the LDAP module, and the
# Samba stuff to the Samba module. This requires that the PAM
# module provides the right hooks.
text = mkDefault
(''
# Account management.
account required pam_unix.so
${optionalString use_ldap
"account sufficient ${pam_ldap}/lib/security/pam_ldap.so"}
${optionalString (config.services.sssd.enable && cfg.sssdStrictAccess==false)
"account sufficient ${pkgs.sssd}/lib/security/pam_sss.so"}
${optionalString (config.services.sssd.enable && cfg.sssdStrictAccess)
"account [default=bad success=ok user_unknown=ignore] ${pkgs.sssd}/lib/security/pam_sss.so"}
${optionalString config.krb5.enable
"account sufficient ${pam_krb5}/lib/security/pam_krb5.so"}
${optionalString cfg.googleOsLoginAccountVerification ''
account [success=ok ignore=ignore default=die] ${pkgs.google-compute-engine-oslogin}/lib/pam_oslogin_login.so
account [success=ok default=ignore] ${pkgs.google-compute-engine-oslogin}/lib/pam_oslogin_admin.so
''}
# Authentication management.
${optionalString cfg.googleOsLoginAuthentication
"auth [success=done perm_denied=bad default=ignore] ${pkgs.google-compute-engine-oslogin}/lib/pam_oslogin_login.so"}
${optionalString cfg.rootOK
"auth sufficient pam_rootok.so"}
${optionalString cfg.requireWheel
"auth required pam_wheel.so use_uid"}
${optionalString cfg.logFailures
"auth required pam_tally.so"}
${optionalString (config.security.pam.enableSSHAgentAuth && cfg.sshAgentAuth)
"auth sufficient ${pkgs.pam_ssh_agent_auth}/libexec/pam_ssh_agent_auth.so file=~/.ssh/authorized_keys:~/.ssh/authorized_keys2:/etc/ssh/authorized_keys.d/%u"}
${optionalString cfg.fprintAuth
"auth sufficient ${pkgs.fprintd}/lib/security/pam_fprintd.so"}
${optionalString cfg.u2fAuth
"auth sufficient ${pkgs.pam_u2f}/lib/security/pam_u2f.so"}
${optionalString cfg.usbAuth
"auth sufficient ${pkgs.pam_usb}/lib/security/pam_usb.so"}
${let oath = config.security.pam.oath; in optionalString cfg.oathAuth
"auth requisite ${pkgs.oathToolkit}/lib/security/pam_oath.so window=${toString oath.window} usersfile=${toString oath.usersFile} digits=${toString oath.digits}"}
'' +
# Modules in this block require having the password set in PAM_AUTHTOK.
# pam_unix is marked as 'sufficient' on NixOS which means nothing will run
# after it succeeds. Certain modules need to run after pam_unix
# prompts the user for password so we run it once with 'required' at an
# earlier point and it will run again with 'sufficient&
|