From 8a88b8b0b5924f8ed00a49e79714cb005cffc7cb Mon Sep 17 00:00:00 2001 From: Brian Cully Date: Tue, 18 Jul 2023 10:06:16 -0400 Subject: [PATCH] services: Add pam-mount-volume-service-type. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The `pam-mount-volumes-service-type' adds additional volumes to the pam-mount-service-type in addition to any that are already specified in `pam-mount-rules'. * doc/guix.texi (PAM Mount Volume Service): add documentation for `pam-mount-service-type'. * gnu/services/pam-mount.scm: new file. * Makefile.am: add pam-mount tests * tests/services/pam-mount.scm: new tests Signed-off-by: Ludovic Courtès --- Makefile.am | 1 + doc/guix.texi | 99 ++++++++++++++++++++++++++++++ gnu/services/pam-mount.scm | 114 ++++++++++++++++++++++++++++++++++- tests/services/pam-mount.scm | 83 +++++++++++++++++++++++++ 4 files changed, 296 insertions(+), 1 deletion(-) create mode 100644 tests/services/pam-mount.scm diff --git a/Makefile.am b/Makefile.am index ca9ec48fa3..693e14effe 100644 --- a/Makefile.am +++ b/Makefile.am @@ -559,6 +559,7 @@ SCM_TESTS = \ tests/services/configuration.scm \ tests/services/lightdm.scm \ tests/services/linux.scm \ + tests/services/pam-mount.scm \ tests/services/telephony.scm \ tests/services/vpn.scm \ tests/sets.scm \ diff --git a/doc/guix.texi b/doc/guix.texi index 65ca18a1be..71f9f29169 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -116,6 +116,7 @@ Copyright @copyright{} 2022 Antero Mejr@* Copyright @copyright{} 2023 Karl Hallsby@* Copyright @copyright{} 2023 Nathaniel Nicandro@* Copyright @copyright{} 2023 Tanguy Le Carrour@* +Copyright @copyright{} 2023 Brian Cully@* Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or @@ -37927,6 +37928,104 @@ The complete list of possible options can be found in the man page for @end table @end deftp +@subheading PAM Mount Volume Service +@cindex pam volume mounting + +PAM mount volumes are automatically mounted at login by the PAM login +service according to a set of per-volume rules. Because they are +mounted by PAM the password entered during login may be used directly to +mount authenticated volumes, such as @code{cifs}, using the same +credentials. + +These volumes will be added in addition to any volumes directly +specified in @code{pam-mount-rules}. + +Here is an example of a rule which will mount a remote CIFS share from +@file{//remote-server/share} into a sub-directory of @file{/shares} +named after the user logging in: + +@lisp +(simple-service 'pam-mount-remote-share pam-mount-volume-service-type + (list (pam-mount-volume + (secondary-group "users") + (file-system-type "cifs") + (server "remote-server") + (file-name "share") + (mount-point "/shares/%(USER)") + (options "nosuid,nodev,seal,cifsacl")))) +@end lisp + +@deftp {Data Type} pam-mount-volume-service-type +Configuration for a single volume to be mounted. Any fields not +specified will be omitted from the run-time PAM configuration. See +@uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, +the man page} for the default values when unspecified. + +@table @asis +@item @code{user-name} (type: maybe-string) +Mount the volume for the given user. + +@item @code{user-id} (type: maybe-integer-or-range) +Mount the volume for the user with this ID. This field may also be +specified as a pair of @code{(start . end)} indicating a range of user +IDs for whom to mount the volume. + +@item @code{primary-group} (type: maybe-string) +Mount the volume for users with this primary group name. + +@item @code{group-id} (type: maybe-integer-or-range) +Mount the volume for the users with this primary group ID. This field +may also be specified as a cons cell of @code{(start . end)} indicating +a range of group ids for whom to mount the volume. + +@item @code{secondary-group} (type: maybe-string) +Mount the volume for users who are members of this group as either a +primary or secondary group. + +@item @code{file-system-type} (type: maybe-string) +The file system type for the volume being mounted (e.g., @code{cifs}) + +@item @code{no-mount-as-root?} (type: maybe-boolean) +Whether or not to mount the volume with root privileges. This is +normally disabled, but may be enabled for mounts of type @code{fuse}, or +other user-level mounts. + +@item @code{server} (type: maybe-string) +The name of the remote server to mount the volume from, when necessary. + +@item @code{file-name} (type: maybe-string) +The location of the volume, either local or remote, depending on the +@code{file-system-type}. + +@item @code{mount-point} (type: maybe-string) +Where to mount the volume in the local file-system. This may be set to +@file{~} to indicate the home directory of the user logging in. If this +field is omitted then @file{/etc/fstab} is consulted for the mount +destination. + +@item @code{options} (type: maybe-string) +The options to be passed as-is to the underlying mount program. + +@item @code{ssh?} (type: maybe-boolean) +Enable this option to pass the login password to SSH for use with mounts +involving SSH (e.g., @code{sshfs}). + +@item @code{cipher} (type: maybe-string) +Cryptsetup cipher name for the volume. To be used with the @code{crypt} +@code{file-system-type}. + +@item @code{file-system-key-cipher} (type: maybe-string) +Cipher name used by the target volume. + +@item @code{file-system-key-hash} (type: maybe-string) +SSL hash name used by the target volume. + +@item @code{file-system-key-file-name} (type: maybe-string) +File name of the file system key for the target volume. + +@end table +@end deftp + @node Guix Services @subsection Guix Services diff --git a/gnu/services/pam-mount.scm b/gnu/services/pam-mount.scm index 21c34ddd61..dbb9d0285f 100644 --- a/gnu/services/pam-mount.scm +++ b/gnu/services/pam-mount.scm @@ -1,5 +1,6 @@ ;;; GNU Guix --- Functional package management for GNU ;;; Copyright © 2019 Guillaume Le Vaillant +;;; Copyright © 2023 Brian Cully ;;; ;;; This file is part of GNU Guix. ;;; @@ -23,9 +24,15 @@ (define-module (gnu services pam-mount) #:use-module (gnu system pam) #:use-module (guix gexp) #:use-module (guix records) + #:use-module (ice-9 match) + #:use-module (srfi srfi-1) #:export (pam-mount-configuration pam-mount-configuration? - pam-mount-service-type)) + pam-mount-service-type + + pam-mount-volume + pam-mount-volume? + pam-mount-volume-service-type)) (define %pam-mount-default-configuration `((debug (@ (enable "0"))) @@ -102,6 +109,11 @@ (module #~(string-append #$pam-mount "/lib/security/pam_mount.so")))) (list optional-pam-mount)))) pam)))))) +(define (extend-pam-mount-configuration initial extensions) + "Extends INITIAL with EXTENSIONS." + (pam-mount-configuration (rules (append (pam-mount-configuration-rules + initial) extensions)))) + (define pam-mount-service-type (service-type (name 'pam-mount) @@ -109,6 +121,106 @@ (define pam-mount-service-type pam-mount-etc-service) (service-extension pam-root-service-type pam-mount-pam-service))) + (compose concatenate) + (extend extend-pam-mount-configuration) (default-value (pam-mount-configuration)) (description "Activate PAM-Mount support. It allows mounting volumes for specific users when they log in."))) + +(define (field-name->tag field-name) + "Convert FIELD-NAME to its tag used by the configuration XML." + (match field-name + ('user-name 'user) + ('user-id 'uid) + ('primary-group 'pgrp) + ('group-id 'gid) + ('secondary-group 'sgrp) + ('file-system-type 'fstype) + ('no-mount-as-root? 'noroot) + ('file-name 'path) + ('mount-point 'mountpoint) + ('ssh? 'ssh) + ('file-system-key-cipher 'fskeycipher) + ('file-system-key-hash 'fskeyhash) + ('file-system-key-file-name 'fskeypath) + (_ field-name))) + +(define-maybe string) + +(define (serialize-string field-name value) + (list (field-name->tag field-name) value)) + +(define (integer-or-range? value) + (match value + ((start . end) (and (integer? start) + (integer? end))) + (_ (number? value)))) + +(define-maybe integer-or-range) + +(define (serialize-integer-or-range field-name value) + (let ((value-string (match value + ((start . end) (format #f "~a-~a" start end)) + (_ (number->string value))))) + (list (field-name->tag field-name) value-string))) + +(define-maybe boolean) + +(define (serialize-boolean field-name value) + (let ((value-string (if value "1" "0"))) + (list (field-name->tag field-name) value-string))) + +(define-configuration pam-mount-volume + (user-name maybe-string "User name to match.") + (user-id maybe-integer-or-range + "User ID, or range of user IDs, in the form of @code{(start . end)} to\nmatch.") + (primary-group maybe-string "Primary group name to match.") + (group-id maybe-integer-or-range + "Group ID, or range of group IDs, in the form of @code{(start . end)} to\nmatch.") + (secondary-group maybe-string + "Match users who belong to this group name as either a primary or secondary\ngroup.") + (file-system-type maybe-string "File system type of volume being mounted.") + (no-mount-as-root? maybe-boolean + "Do not use super user privileges to mount this volume.") + (server maybe-string "Remote server this volume resides on.") + (file-name maybe-string "Location of the volume to be mounted.") + (mount-point maybe-string + "Where to mount the volume in the local file system.") + (options maybe-string "Options to pass to the underlying mount program.") + (ssh? maybe-boolean "Whether to pass the login password to SSH.") + (cipher maybe-string "Cryptsetup cipher named used by volume.") + (file-system-key-cipher maybe-string + "Cipher name used by the target volume.") + (file-system-key-hash maybe-string + "SSL hash name used by the target volume.") + (file-system-key-file-name maybe-string + "File name for the file system key used by the target volume.")) + +(define (pam-mount-volume->sxml volume) + ;; Convert a list of configuration fields into an SXML-compatible attribute + ;; list. + (define xml-attrs + (filter-map (lambda (field) + (let* ((accessor (configuration-field-getter field)) + (value (accessor volume))) + (and (not (eq? value %unset-value)) + (list (field-name->tag (configuration-field-name + field)) value)))) + pam-mount-volume-fields)) + + `(volume (@ ,@xml-attrs))) + +(define (pam-mount-volume-rules volumes) + (map pam-mount-volume->sxml volumes)) + +(define pam-mount-volume-service-type + (service-type (name 'pam-mount-volume) + (extensions (list (service-extension pam-mount-service-type + pam-mount-volume-rules))) + (compose concatenate) + (extend append) + (default-value '()) + (description + "Mount remote volumes such as CIFS shares @i{via} +@acronym{PAM, Pluggable Authentication Modules} when logging in, using login +credentials."))) diff --git a/tests/services/pam-mount.scm b/tests/services/pam-mount.scm new file mode 100644 index 0000000000..bfbd15967f --- /dev/null +++ b/tests/services/pam-mount.scm @@ -0,0 +1,83 @@ +;;; GNU Guix --- Functional package management for GNU +;;; Copyright © 2023 Brian Cully +;;; +;;; This file is part of GNU Guix. +;;; +;;; GNU Guix is free software; you can redistribute it and/or modify it +;;; under the terms of the GNU General Public License as published by +;;; the Free Software Foundation; either version 3 of the License, or (at +;;; your option) any later version. +;;; +;;; GNU Guix is distributed in the hope that it will be useful, but +;;; WITHOUT ANY WARRANTY; without even the implied warranty of +;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +;;; GNU General Public License for more details. +;;; +;;; You should have received a copy of the GNU General Public License +;;; along with GNU Guix. If not, see . + +(define-module (tests services pam-mount) + #:use-module (gnu services pam-mount) + #:use-module (gnu system pam) + #:use-module (gnu services) + #:use-module (gnu services configuration) + #:use-module (guix derivations) + #:use-module (guix gexp) + #:use-module (guix grafts) + #:use-module (guix store) + #:use-module (guix tests) + #:use-module (ice-9 match) + #:use-module (srfi srfi-1) + #:use-module (srfi srfi-64)) + +(define pam-mount-volume-fields (@@ (gnu services pam-mount) + pam-mount-volume-fields)) +(define field-name->tag (@@ (gnu services pam-mount) + field-name->tag)) + +(define pam-mount-volume->sxml (@@ (gnu services pam-mount) + pam-mount-volume->sxml)) + +(test-begin "services-pam-mount") + +(test-group "field-name->tag" + (let ((field-map '((user-name user) + (user-id uid) + (primary-group pgrp) + (group-id gid) + (secondary-group sgrp) + (file-system-type fstype) + (no-mount-as-root? noroot) + (server server) + (file-name path) + (mount-point mountpoint) + (options options) + (ssh? ssh) + (cipher cipher) + (file-system-key-cipher fskeycipher) + (file-system-key-hash fskeyhash) + (file-system-key-file-name fskeypath)))) + + (test-equal "all fields accounted for" + (map car field-map) + (map configuration-field-name pam-mount-volume-fields)) + + (for-each (match-lambda + ((field-name tag-name) + (test-eq (format #f "~a -> ~a" field-name tag-name) + (field-name->tag field-name) tag-name))) + field-map))) + +(let ((tmpfs-volume (pam-mount-volume + (secondary-group "users") + (file-system-type "tmpfs") + (mount-point "/run/user/%(USERUID)") + (options "someoptions")))) + (test-equal "tmpfs" + '(volume (@ (sgrp "users") + (fstype "tmpfs") + (mountpoint "/run/user/%(USERUID)") + (options "someoptions"))) + (pam-mount-volume->sxml tmpfs-volume))) + +(test-end "services-pam-mount")