gnu/services/mail.scm

   1 ;;; GNU Guix --- Functional package management for GNU
   2 ;;; Copyright © 2015 Andy Wingo <wingo@igalia.com>
   3 ;;; Copyright © 2017, 2018 Clément Lassieur <clement@lassieur.org>
   4 ;;; Copyright © 2017 Carlo Zancanaro <carlo@zancanaro.id.au>
   5 ;;; Copyright © 2017 Tobias Geerinckx-Rice <me@tobias.gr>
   6 ;;;
   7 ;;; This file is part of GNU Guix.
   8 ;;;
   9 ;;; GNU Guix is free software; you can redistribute it and/or modify it
  10 ;;; under the terms of the GNU General Public License as published by
  11 ;;; the Free Software Foundation; either version 3 of the License, or (at
  12 ;;; your option) any later version.
  13 ;;;
  14 ;;; GNU Guix is distributed in the hope that it will be useful, but
  15 ;;; WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;;; GNU General Public License for more details.
  18 ;;;
  19 ;;; You should have received a copy of the GNU General Public License
  20 ;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
  21 ;;;
  22 ;;; Some of the help text was taken from the default dovecot.conf files.
  23
  24 (define-module (gnu services mail)
  25   #:use-module (gnu services)
  26   #:use-module (gnu services base)
  27   #:use-module (gnu services configuration)
  28   #:use-module (gnu services shepherd)
  29   #:use-module (gnu system pam)
  30   #:use-module (gnu system shadow)
  31   #:use-module (gnu packages mail)
  32   #:use-module (gnu packages admin)
  33   #:use-module (gnu packages tls)
  34   #:use-module (guix records)
  35   #:use-module (guix packages)
  36   #:use-module (guix gexp)
  37   #:use-module (ice-9 match)
  38   #:use-module (ice-9 format)
  39   #:use-module (srfi srfi-1)
  40   #:export (dovecot-service
  41             dovecot-service-type
  42             dovecot-configuration
  43             opaque-dovecot-configuration
  44
  45             dict-configuration
  46             passdb-configuration
  47             userdb-configuration
  48             unix-listener-configuration
  49             fifo-listener-configuration
  50             inet-listener-configuration
  51             service-configuration
  52             protocol-configuration
  53             plugin-configuration
  54             mailbox-configuration
  55             namespace-configuration
  56
  57             opensmtpd-configuration
  58             opensmtpd-configuration?
  59             opensmtpd-service-type
  60             %default-opensmtpd-config-file
  61
  62             mail-aliases-service-type
  63
  64             exim-configuration
  65             exim-configuration?
  66             exim-service-type
  67             %default-exim-config-file))
  68
  69 ;;; Commentary:
  70 ;;;
  71 ;;; This module provides service definitions for the Dovecot POP3 and IMAP
  72 ;;; mail server.
  73 ;;;
  74 ;;; Code:
  75
  76 (define (uglify-field-name field-name)
  77   (let ((str (symbol->string field-name)))
  78     (string-join (string-split (if (string-suffix? "?" str)
  79                                    (substring str 0 (1- (string-length str)))
  80                                    str)
  81                                #\-)
  82                  "_")))
  83
  84 (define (serialize-field field-name val)
  85   (format #t "~a=~a\n" (uglify-field-name field-name) val))
  86
  87 (define (serialize-string field-name val)
  88   (serialize-field field-name val))
  89
  90 (define (space-separated-string-list? val)
  91   (and (list? val)
  92        (and-map (lambda (x)
  93                   (and (string? x) (not (string-index x #\space))))
  94                 val)))
  95 (define (serialize-space-separated-string-list field-name val)
  96   (serialize-field field-name (string-join val " ")))
  97
  98 (define (comma-separated-string-list? val)
  99   (and (list? val)
 100        (and-map (lambda (x)
 101                   (and (string? x) (not (string-index x #\,))))
 102                 val)))
 103 (define (serialize-comma-separated-string-list field-name val)
 104   (serialize-field field-name (string-join val ",")))
 105
 106 (define (file-name? val)
 107   (and (string? val)
 108        (string-prefix? "/" val)))
 109 (define (serialize-file-name field-name val)
 110   (serialize-string field-name val))
 111
 112 (define (colon-separated-file-name-list? val)
 113   (and (list? val)
 114        ;; Trailing slashes not needed and not
 115        (and-map file-name? val)))
 116 (define (serialize-colon-separated-file-name-list field-name val)
 117   (serialize-field field-name (string-join val ":")))
 118
 119 (define (serialize-boolean field-name val)
 120   (serialize-string field-name (if val "yes" "no")))
 121
 122 (define (non-negative-integer? val)
 123   (and (exact-integer? val) (not (negative? val))))
 124 (define (serialize-non-negative-integer field-name val)
 125   (serialize-field field-name val))
 126
 127 (define (hours? val) (non-negative-integer? val))
 128 (define (serialize-hours field-name val)
 129   (serialize-field field-name (format #f "~a hours" val)))
 130
 131 (define (free-form-fields? val)
 132   (match val
 133     (() #t)
 134     ((((? symbol?) . (? string)) . val) (free-form-fields? val))
 135     (_ #f)))
 136 (define (serialize-free-form-fields field-name val)
 137   (for-each (match-lambda ((k . v) (serialize-field k v))) val))
 138
 139 (define (free-form-args? val)
 140   (match val
 141     (() #t)
 142     ((((? symbol?) . (? string)) . val) (free-form-args? val))
 143     (_ #f)))
 144 (define (serialize-free-form-args field-name val)
 145   (serialize-field field-name
 146                    (string-join
 147                     (map (match-lambda ((k . v) (format #t "~a=~a" k v))) val)
 148                     " ")))
 149
 150 (define-configuration dict-configuration
 151   (entries
 152    (free-form-fields '())
 153    "A list of key-value pairs that this dict should hold."))
 154
 155 (define (serialize-dict-configuration field-name val)
 156   (format #t "dict {\n")
 157   (serialize-configuration val dict-configuration-fields)
 158   (format #t "}\n"))
 159
 160 (define-configuration passdb-configuration
 161   (driver
 162    (string "pam")
 163    "The driver that the passdb should use.  Valid values include
 164 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
 165 @samp{static}.")
 166   (args
 167    (space-separated-string-list '())
 168    "Space separated list of arguments to the passdb driver."))
 169
 170 (define (serialize-passdb-configuration field-name val)
 171   (format #t "passdb {\n")
 172   (serialize-configuration val passdb-configuration-fields)
 173   (format #t "}\n"))
 174 (define (passdb-configuration-list? val)
 175   (and (list? val) (and-map passdb-configuration? val)))
 176 (define (serialize-passdb-configuration-list field-name val)
 177   (for-each (lambda (val) (serialize-passdb-configuration field-name val)) val))
 178
 179 (define-configuration userdb-configuration
 180   (driver
 181    (string "passwd")
 182    "The driver that the userdb should use.  Valid values include
 183 @samp{passwd} and @samp{static}.")
 184   (args
 185    (space-separated-string-list '())
 186    "Space separated list of arguments to the userdb driver.")
 187   (override-fields
 188    (free-form-args '())
 189    "Override fields from passwd."))
 190
 191 (define (serialize-userdb-configuration field-name val)
 192   (format #t "userdb {\n")
 193   (serialize-configuration val userdb-configuration-fields)
 194   (format #t "}\n"))
 195 (define (userdb-configuration-list? val)
 196   (and (list? val) (and-map userdb-configuration? val)))
 197 (define (serialize-userdb-configuration-list field-name val)
 198   (for-each (lambda (val) (serialize-userdb-configuration field-name val)) val))
 199
 200 (define-configuration unix-listener-configuration
 201   (path
 202    (string (configuration-missing-field 'unix-listener 'path))
 203    "Path to the file, relative to @code{base-dir} field.  This is also used as
 204 the section name.")
 205   (mode
 206    (string "0600")
 207    "The access mode for the socket.")
 208   (user
 209    (string "")
 210    "The user to own the the socket.")
 211   (group
 212    (string "")
 213    "The group to own the socket."))
 214
 215 (define (serialize-unix-listener-configuration field-name val)
 216   (format #t "unix_listener ~a {\n" (unix-listener-configuration-path val))
 217   (serialize-configuration val (cdr unix-listener-configuration-fields))
 218   (format #t "}\n"))
 219
 220 (define-configuration fifo-listener-configuration
 221   (path
 222    (string (configuration-missing-field 'fifo-listener 'path))
 223    "Path to the file, relative to @code{base-dir} field.  This is also used as
 224 the section name.")
 225   (mode
 226    (string "0600")
 227    "The access mode for the socket.")
 228   (user
 229    (string "")
 230    "The user to own the the socket.")
 231   (group
 232    (string "")
 233    "The group to own the socket."))
 234
 235 (define (serialize-fifo-listener-configuration field-name val)
 236   (format #t "fifo_listener ~a {\n" (fifo-listener-configuration-path val))
 237   (serialize-configuration val (cdr fifo-listener-configuration-fields))
 238   (format #t "}\n"))
 239
 240 (define-configuration inet-listener-configuration
 241   (protocol
 242    (string (configuration-missing-field 'inet-listener 'protocol))
 243    "The protocol to listen for.")
 244   (address
 245    (string "")
 246    "The address on which to listen, or empty for all addresses.")
 247   (port
 248    (non-negative-integer
 249     (configuration-missing-field 'inet-listener 'port))
 250    "The port on which to listen.")
 251   (ssl?
 252    (boolean #t)
 253    "Whether to use SSL for this service; @samp{yes}, @samp{no}, or
 254 @samp{required}."))
 255
 256 (define (serialize-inet-listener-configuration field-name val)
 257   (format #t "inet_listener ~a {\n" (inet-listener-configuration-protocol val))
 258   (serialize-configuration val (cdr inet-listener-configuration-fields))
 259   (format #t "}\n"))
 260
 261 (define (listener-configuration? val)
 262   (or (unix-listener-configuration? val)
 263       (fifo-listener-configuration? val)
 264       (inet-listener-configuration? val)))
 265 (define (serialize-listener-configuration field-name val)
 266   (cond
 267    ((unix-listener-configuration? val)
 268     (serialize-unix-listener-configuration field-name val))
 269    ((fifo-listener-configuration? val)
 270     (serialize-fifo-listener-configuration field-name val))
 271    ((inet-listener-configuration? val)
 272     (serialize-inet-listener-configuration field-name val))
 273    (else (configuration-field-error field-name val))))
 274 (define (listener-configuration-list? val)
 275   (and (list? val) (and-map listener-configuration? val)))
 276 (define (serialize-listener-configuration-list field-name val)
 277   (for-each (lambda (val)
 278               (serialize-listener-configuration field-name val))
 279             val))
 280
 281 (define-configuration service-configuration
 282   (kind
 283    (string (configuration-missing-field 'service 'kind))
 284    "The service kind.  Valid values include @code{director},
 285 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
 286 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
 287 @code{tcpwrap}, @code{quota-warning}, or anything else.")
 288   (listeners
 289    (listener-configuration-list '())
 290    "Listeners for the service.  A listener is either an
 291 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
 292 an @code{inet-listener-configuration}.")
 293   (client-limit
 294    (non-negative-integer 0)
 295    "Maximum number of simultaneous client connections per process.  Once this
 296 number of connections is received, the next incoming connection will prompt
 297 Dovecot to spawn another process.  If set to 0, @code{default-client-limit} is
 298 used instead.")
 299   (service-count
 300    (non-negative-integer 1)
 301    "Number of connections to handle before starting a new process.
 302 Typically the only useful values are 0 (unlimited) or 1.  1 is more
 303 secure, but 0 is faster.  <doc/wiki/LoginProcess.txt>.")
 304   (process-limit
 305    (non-negative-integer 0)
 306    "Maximum number of processes that can exist for this service.  If set to 0,
 307 @code{default-process-limit} is used instead.")
 308   (process-min-avail
 309    (non-negative-integer 0)
 310    "Number of processes to always keep waiting for more connections.")
 311   ;; FIXME: Need to be able to take the default for this value from other
 312   ;; parts of the config.
 313   (vsz-limit
 314    (non-negative-integer #e256e6)
 315    "If you set @samp{service-count 0}, you probably need to grow
 316 this."))
 317
 318 (define (serialize-service-configuration field-name val)
 319   (format #t "service ~a {\n" (service-configuration-kind val))
 320   (serialize-configuration val (cdr service-configuration-fields))
 321   (format #t "}\n"))
 322 (define (service-configuration-list? val)
 323   (and (list? val) (and-map service-configuration? val)))
 324 (define (serialize-service-configuration-list field-name val)
 325   (for-each (lambda (val)
 326               (serialize-service-configuration field-name val))
 327             val))
 328
 329 (define-configuration protocol-configuration
 330   (name
 331    (string (configuration-missing-field 'protocol 'name))
 332    "The name of the protocol.")
 333   (auth-socket-path
 334    (string "/var/run/dovecot/auth-userdb")
 335    "UNIX socket path to master authentication server to find users.
 336 This is used by imap (for shared users) and lda.")
 337   (mail-plugins
 338    (space-separated-string-list '("$mail_plugins"))
 339    "Space separated list of plugins to load.")
 340   (mail-max-userip-connections
 341    (non-negative-integer 10)
 342    "Maximum number of IMAP connections allowed for a user from each IP
 343 address.  NOTE: The username is compared case-sensitively."))
 344
 345 (define (serialize-protocol-configuration field-name val)
 346   (format #t "protocol ~a {\n" (protocol-configuration-name val))
 347   (serialize-configuration val (cdr protocol-configuration-fields))
 348   (format #t "}\n"))
 349 (define (protocol-configuration-list? val)
 350   (and (list? val) (and-map protocol-configuration? val)))
 351 (define (serialize-protocol-configuration-list field-name val)
 352   (serialize-field 'protocols
 353                    (string-join (map protocol-configuration-name val) " "))
 354   (for-each (lambda (val)
 355               (serialize-protocol-configuration field-name val))
 356             val))
 357
 358 (define-configuration plugin-configuration
 359   (entries
 360    (free-form-fields '())
 361    "A list of key-value pairs that this dict should hold."))
 362
 363 (define (serialize-plugin-configuration field-name val)
 364   (format #t "plugin {\n")
 365   (serialize-configuration val plugin-configuration-fields)
 366   (format #t "}\n"))
 367
 368 (define-configuration mailbox-configuration
 369   (name
 370    (string (error "mailbox name is required"))
 371    "Name for this mailbox.")
 372
 373   (auto
 374    (string "no")
 375    "@samp{create} will automatically create this mailbox.
 376 @samp{subscribe} will both create and subscribe to the mailbox.")
 377
 378   (special-use
 379    (space-separated-string-list '())
 380    "List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
 381 Valid values are @code{\\All}, @code{\\Archive}, @code{\\Drafts},
 382 @code{\\Flagged}, @code{\\Junk}, @code{\\Sent}, and @code{\\Trash}."))
 383
 384 (define (serialize-mailbox-configuration field-name val)
 385   (format #t "mailbox \"~a\" {\n" (mailbox-configuration-name val))
 386   (serialize-configuration val (cdr mailbox-configuration-fields))
 387   (format #t "}\n"))
 388 (define (mailbox-configuration-list? val)
 389   (and (list? val) (and-map mailbox-configuration? val)))
 390 (define (serialize-mailbox-configuration-list field-name val)
 391   (for-each (lambda (val)
 392               (serialize-mailbox-configuration field-name val))
 393             val))
 394
 395 (define-configuration namespace-configuration
 396   (name
 397    (string (error "namespace name is required"))
 398    "Name for this namespace.")
 399
 400   (type
 401    (string "private")
 402    "Namespace type: @samp{private}, @samp{shared} or @samp{public}.")
 403
 404   (separator
 405    (string "")
 406    "Hierarchy separator to use. You should use the same separator for
 407 all namespaces or some clients get confused.  @samp{/} is usually a good
 408 one.  The default however depends on the underlying mail storage
 409 format.")
 410
 411   (prefix
 412    (string "")
 413    "Prefix required to access this namespace.  This needs to be
 414 different for all namespaces. For example @samp{Public/}.")
 415
 416   (location
 417    (string "")
 418    "Physical location of the mailbox. This is in same format as
 419 mail_location, which is also the default for it.")
 420
 421   (inbox?
 422    (boolean #f)
 423    "There can be only one INBOX, and this setting defines which
 424 namespace has it.")
 425
 426   (hidden?
 427    (boolean #f)
 428    "If namespace is hidden, it's not advertised to clients via NAMESPACE
 429 extension. You'll most likely also want to set @samp{list? #f}.  This is mostly
 430 useful when converting from another server with different namespaces
 431 which you want to deprecate but still keep working.  For example you can
 432 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
 433 and @samp{mail/}.")
 434
 435   (list?
 436    (boolean #t)
 437    "Show the mailboxes under this namespace with LIST command. This
 438 makes the namespace visible for clients that don't support NAMESPACE
 439 extension.  The special @code{children} value lists child mailboxes, but
 440 hides the namespace prefix.")
 441
 442   (subscriptions?
 443    (boolean #t)
 444    "Namespace handles its own subscriptions.  If set to @code{#f}, the
 445 parent namespace handles them.  The empty prefix should always have this
 446 as @code{#t}.)")
 447
 448   (mailboxes
 449    (mailbox-configuration-list '())
 450    "List of predefined mailboxes in this namespace."))
 451
 452 (define (serialize-namespace-configuration field-name val)
 453   (format #t "namespace ~a {\n" (namespace-configuration-name val))
 454   (serialize-configuration val (cdr namespace-configuration-fields))
 455   (format #t "}\n"))
 456 (define (list-of-namespace-configuration? val)
 457   (and (list? val) (and-map namespace-configuration? val)))
 458 (define (serialize-list-of-namespace-configuration field-name val)
 459   (for-each (lambda (val)
 460               (serialize-namespace-configuration field-name val))
 461             val))
 462
 463 (define-configuration dovecot-configuration
 464   (dovecot
 465    (package dovecot)
 466    "The dovecot package.")
 467
 468   (listen
 469    (comma-separated-string-list '("*" "::"))
 470    "A list of IPs or hosts where to listen in for connections.  @samp{*}
 471 listens in all IPv4 interfaces, @samp{::} listens in all IPv6
 472 interfaces.  If you want to specify non-default ports or anything more
 473 complex, customize the address and port fields of the
 474 @samp{inet-listener} of the specific services you are interested in.")
 475
 476   (protocols
 477    (protocol-configuration-list
 478     (list (protocol-configuration
 479            (name "imap"))))
 480    "List of protocols we want to serve.  Available protocols include
 481 @samp{imap}, @samp{pop3}, and @samp{lmtp}.")
 482
 483   (services
 484    (service-configuration-list
 485     (list
 486      (service-configuration
 487       (kind "imap-login")
 488       (client-limit 0)
 489       (process-limit 0)
 490       (listeners
 491        (list
 492         (inet-listener-configuration (protocol "imap") (port 143) (ssl? #f))
 493         (inet-listener-configuration (protocol "imaps") (port 993) (ssl? #t)))))
 494      (service-configuration
 495       (kind "pop3-login")
 496       (listeners
 497        (list
 498         (inet-listener-configuration (protocol "pop3") (port 110) (ssl? #f))
 499         (inet-listener-configuration (protocol "pop3s") (port 995) (ssl? #t)))))
 500      (service-configuration
 501       (kind "lmtp")
 502       (client-limit 1)
 503       (process-limit 0)
 504       (listeners
 505        (list (unix-listener-configuration (path "lmtp") (mode "0666")))))
 506      (service-configuration
 507       (kind "imap")
 508       (client-limit 1)
 509       (process-limit 1024))
 510      (service-configuration
 511       (kind "pop3")
 512       (client-limit 1)
 513       (process-limit 1024))
 514      (service-configuration (kind "auth")
 515       ;; In what could be taken to be a bug, the default value of 1 for
 516       ;; service-count makes it so that a PAM auth worker can't fork off
 517       ;; subprocesses for making blocking queries.  The result is that nobody
 518       ;; can log in -- very secure, but not very useful!  If we simply omit
 519       ;; the service-count, it will default to the value of
 520       ;; auth-worker-max-count, which is 30, instead of defaulting to 1, which
 521       ;; is the default for all other services.  As a hack, bump this value to
 522       ;; 30.
 523       (service-count 30)
 524       (client-limit 0)
 525       (process-limit 1)
 526       (listeners
 527        (list (unix-listener-configuration (path "auth-userdb")))))
 528      (service-configuration
 529       (kind "auth-worker")
 530       (client-limit 1)
 531       (process-limit 0))
 532      (service-configuration
 533       (kind "dict")
 534       (client-limit 1)
 535       (process-limit 0)
 536       (listeners (list (unix-listener-configuration (path "dict")))))))
 537    "List of services to enable.  Available services include @samp{imap},
 538 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
 539 @samp{lmtp}.")
 540
 541   (dict
 542    (dict-configuration (dict-configuration))
 543    "Dict configuration, as created by the @code{dict-configuration}
 544 constructor.")
 545
 546   (passdbs
 547    (passdb-configuration-list (list (passdb-configuration (driver "pam"))))
 548    "List of passdb configurations, each one created by the
 549 @code{passdb-configuration} constructor.")
 550
 551   (userdbs
 552    (userdb-configuration-list (list (userdb-configuration (driver "passwd"))))
 553    "List of userdb configurations, each one created by the
 554 @code{userdb-configuration} constructor.")
 555
 556   (plugin-configuration
 557    (plugin-configuration (plugin-configuration))
 558    "Plug-in configuration, created by the @code{plugin-configuration}
 559 constructor.")
 560
 561   (namespaces
 562    (list-of-namespace-configuration
 563     (list
 564      (namespace-configuration
 565       (name "inbox")
 566       (prefix "")
 567       (inbox? #t)
 568       (mailboxes
 569        (list
 570         (mailbox-configuration (name "Drafts") (special-use '("\\Drafts")))
 571         (mailbox-configuration (name "Junk") (special-use '("\\Junk")))
 572         (mailbox-configuration (name "Trash") (special-use '("\\Trash")))
 573         (mailbox-configuration (name "Sent") (special-use '("\\Sent")))
 574         (mailbox-configuration (name "Sent Messages") (special-use '("\\Sent")))
 575         (mailbox-configuration (name "Drafts") (special-use '("\\Drafts"))))))))
 576    "List of namespaces.  Each item in the list is created by the
 577 @code{namespace-configuration} constructor.")
 578
 579   (base-dir
 580    (file-name "/var/run/dovecot/")
 581    "Base directory where to store runtime data.")
 582
 583   (login-greeting
 584    (string "Dovecot ready.")
 585    "Greeting message for clients.")
 586
 587   (login-trusted-networks
 588    (space-separated-string-list '())
 589    "List of trusted network ranges.  Connections from these IPs are
 590 allowed to override their IP addresses and ports (for logging and for
 591 authentication checks).  @samp{disable-plaintext-auth} is also ignored
 592 for these networks.  Typically you'd specify your IMAP proxy servers
 593 here.")
 594
 595   (login-access-sockets
 596    (space-separated-string-list '())
 597    "List of login access check sockets (e.g. tcpwrap).")
 598
 599   (verbose-proctitle?
 600    (boolean #f)
 601    "Show more verbose process titles (in ps).  Currently shows user name
 602 and IP address.  Useful for seeing who are actually using the IMAP
 603 processes (e.g. shared mailboxes or if same uid is used for multiple
 604 accounts).")
 605
 606   (shutdown-clients?
 607    (boolean #t)
 608    "Should all processes be killed when Dovecot master process shuts down.
 609 Setting this to @code{#f} means that Dovecot can be upgraded without
 610 forcing existing client connections to close (although that could also
 611 be a problem if the upgrade is e.g. because of a security fix).")
 612
 613   (doveadm-worker-count
 614    (non-negative-integer 0)
 615    "If non-zero, run mail commands via this many connections to doveadm
 616 server, instead of running them directly in the same process.")
 617
 618   (doveadm-socket-path
 619    (string "doveadm-server")
 620    "UNIX socket or host:port used for connecting to doveadm server.")
 621
 622   (import-environment
 623    (space-separated-string-list '("TZ"))
 624    "List of environment variables that are preserved on Dovecot startup
 625 and passed down to all of its child processes.  You can also give
 626 key=value pairs to always set specific settings.")
 627
 628 ;;; Authentication processes
 629
 630   (disable-plaintext-auth?
 631    (boolean #t)
 632    "Disable LOGIN command and all other plaintext authentications unless
 633 SSL/TLS is used (LOGINDISABLED capability).  Note that if the remote IP
 634 matches the local IP (i.e. you're connecting from the same computer),
 635 the connection is considered secure and plaintext authentication is
 636 allowed.  See also ssl=required setting.")
 637
 638   (auth-cache-size
 639    (non-negative-integer 0)
 640    "Authentication cache size (e.g. @samp{#e10e6}).  0 means it's disabled.
 641 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
 642 for caching to be used.")
 643
 644   (auth-cache-ttl
 645    (string "1 hour")
 646    "Time to live for cached data.  After TTL expires the cached record
 647 is no longer used, *except* if the main database lookup returns internal
 648 failure.  We also try to handle password changes automatically: If
 649 user's previous authentication was successful, but this one wasn't, the
 650 cache isn't used.  For now this works only with plaintext
 651 authentication.")
 652
 653   (auth-cache-negative-ttl
 654    (string "1 hour")
 655    "TTL for negative hits (user not found, password mismatch).
 656 0 disables caching them completely.")
 657
 658   (auth-realms
 659    (space-separated-string-list '())
 660    "List of realms for SASL authentication mechanisms that need them.
 661 You can leave it empty if you don't want to support multiple realms.
 662 Many clients simply use the first one listed here, so keep the default
 663 realm first.")
 664
 665   (auth-default-realm
 666    (string "")
 667    "Default realm/domain to use if none was specified.  This is used for
 668 both SASL realms and appending @@domain to username in plaintext
 669 logins.")
 670
 671   (auth-username-chars
 672    (string
 673     "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@")
 674    "List of allowed characters in username.  If the user-given username
 675 contains a character not listed in here, the login automatically fails.
 676 This is just an extra check to make sure user can't exploit any
 677 potential quote escaping vulnerabilities with SQL/LDAP databases.  If
 678 you want to allow all characters, set this value to empty.")
 679
 680   (auth-username-translation
 681    (string "")
 682    "Username character translations before it's looked up from
 683 databases.  The value contains series of from -> to characters.  For
 684 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
 685 translated to @samp{@@}.")
 686
 687   (auth-username-format
 688    (string "%Lu")
 689    "Username formatting before it's looked up from databases.  You can
 690 use the standard variables here, e.g. %Lu would lowercase the username,
 691 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
 692 change the @samp{@@} into @samp{-AT-}.  This translation is done after
 693 @samp{auth-username-translation} changes.")
 694
 695   (auth-master-user-separator
 696    (string "")
 697    "If you want to allow master users to log in by specifying the master
 698 username within the normal username string (i.e. not using SASL
 699 mechanism's support for it), you can specify the separator character
 700 here.  The format is then <username><separator><master username>.
 701 UW-IMAP uses @samp{*} as the separator, so that could be a good
 702 choice.")
 703
 704   (auth-anonymous-username
 705    (string "anonymous")
 706    "Username to use for users logging in with ANONYMOUS SASL
 707 mechanism.")
 708
 709   (auth-worker-max-count
 710    (non-negative-integer 30)
 711    "Maximum number of dovecot-auth worker processes.  They're used to
 712 execute blocking passdb and userdb queries (e.g. MySQL and PAM).
 713 They're automatically created and destroyed as needed.")
 714
 715   (auth-gssapi-hostname
 716    (string "")
 717    "Host name to use in GSSAPI principal names.  The default is to use
 718 the name returned by gethostname().  Use @samp{$ALL} (with quotes) to
 719 allow all keytab entries.")
 720
 721   (auth-krb5-keytab
 722    (string "")
 723    "Kerberos keytab to use for the GSSAPI mechanism.  Will use the
 724 system default (usually /etc/krb5.keytab) if not specified.  You may
 725 need to change the auth service to run as root to be able to read this
 726 file.")
 727
 728   (auth-use-winbind?
 729    (boolean #f)
 730    "Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
 731 and @samp{ntlm-auth} helper.
 732 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.")
 733
 734   (auth-winbind-helper-path
 735    (file-name "/usr/bin/ntlm_auth")
 736    "Path for Samba's @samp{ntlm-auth} helper binary.")
 737
 738   (auth-failure-delay
 739    (string "2 secs")
 740    "Time to delay before replying to failed authentications.")
 741
 742   (auth-ssl-require-client-cert?
 743    (boolean #f)
 744    "Require a valid SSL client certificate or the authentication
 745 fails.")
 746
 747   (auth-ssl-username-from-cert?
 748    (boolean #f)
 749    "Take the username from client's SSL certificate, using
 750 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
 751 CommonName.")
 752
 753   (auth-mechanisms
 754    (space-separated-string-list '("plain"))
 755    "List of wanted authentication mechanisms.  Supported mechanisms are:
 756 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
 757 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
 758 @samp{otp}, @samp{skey}, and @samp{gss-spnego}.  NOTE: See also
 759 @samp{disable-plaintext-auth} setting.")
 760
 761   (director-servers
 762    (space-separated-string-list '())
 763    "List of IPs or hostnames to all director servers, including ourself.
 764 Ports can be specified as ip:port.  The default port is the same as what
 765 director service's @samp{inet-listener} is using.")
 766
 767   (director-mail-servers
 768    (space-separated-string-list '())
 769    "List of IPs or hostnames to all backend mail servers.  Ranges are
 770 allowed too, like 10.0.0.10-10.0.0.30.")
 771
 772   (director-user-expire
 773    (string "15 min")
 774    "How long to redirect users to a specific server after it no longer
 775 has any connections.")
 776
 777   (director-username-hash
 778    (string "%Lu")
 779    "How the username is translated before being hashed.  Useful values
 780 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
 781 are shared within domain.")
 782
 783 ;;; Log destination.
 784
 785   (log-path
 786    (string "syslog")
 787    "Log file to use for error messages.  @samp{syslog} logs to syslog,
 788 @samp{/dev/stderr} logs to stderr.")
 789
 790   (info-log-path
 791    (string "")
 792    "Log file to use for informational messages.  Defaults to
 793 @samp{log-path}.")
 794
 795   (debug-log-path
 796    (string "")
 797    "Log file to use for debug messages.  Defaults to
 798 @samp{info-log-path}.")
 799
 800   (syslog-facility
 801    (string "mail")
 802    "Syslog facility to use if you're logging to syslog.  Usually if you
 803 don't want to use @samp{mail}, you'll use local0..local7.  Also other
 804 standard facilities are supported.")
 805
 806   (auth-verbose?
 807    (boolean #f)
 808    "Log unsuccessful authentication attempts and the reasons why they
 809 failed.")
 810
 811   (auth-verbose-passwords?
 812    (boolean #f)
 813    "In case of password mismatches, log the attempted password.  Valid
 814 values are no, plain and sha1.  sha1 can be useful for detecting brute
 815 force password attempts vs.  user simply trying the same password over
 816 and over again.  You can also truncate the value to n chars by appending
 817 \":n\" (e.g. sha1:6).")
 818
 819   (auth-debug?
 820    (boolean #f)
 821    "Even more verbose logging for debugging purposes.  Shows for example
 822 SQL queries.")
 823
 824   (auth-debug-passwords?
 825    (boolean #f)
 826    "In case of password mismatches, log the passwords and used scheme so
 827 the problem can be debugged.  Enabling this also enables
 828 @samp{auth-debug}.")
 829
 830   (mail-debug?
 831    (boolean #f)
 832    "Enable mail process debugging.  This can help you figure out why
 833 Dovecot isn't finding your mails.")
 834
 835   (verbose-ssl?
 836    (boolean #f)
 837    "Show protocol level SSL errors.")
 838
 839   (log-timestamp
 840    (string "\"%b %d %H:%M:%S \"")
 841    "Prefix for each line written to log file.  % codes are in
 842 strftime(3) format.")
 843
 844   (login-log-format-elements
 845    (space-separated-string-list
 846     '("user=<%u>" "method=%m" "rip=%r" "lip=%l" "mpid=%e" "%c"))
 847    "List of elements we want to log.  The elements which have a
 848 non-empty variable value are joined together to form a comma-separated
 849 string.")
 850
 851   (login-log-format
 852    (string "%$: %s")
 853    "Login log format.  %s contains @samp{login-log-format-elements}
 854 string, %$ contains the data we want to log.")
 855
 856   (mail-log-prefix
 857    (string "\"%s(%u)<%{pid}><%{session}>: \"")
 858    "Log prefix for mail processes.  See doc/wiki/Variables.txt for list
 859 of possible variables you can use.")
 860
 861   (deliver-log-format
 862    (string "msgid=%m: %$")
 863    "Format to use for logging mail deliveries.  You can use variables:
 864 @table @code
 865 @item %$
 866 Delivery status message (e.g. @samp{saved to INBOX})
 867 @item %m
 868 Message-ID
 869 @item %s
 870 Subject
 871 @item %f
 872 From address
 873 @item %p
 874 Physical size
 875 @item %w
 876 Virtual size.
 877 @end table")
 878
 879 ;;; Mailbox locations and namespaces
 880
 881   (mail-location
 882    (string "")
 883    "Location for users' mailboxes.  The default is empty, which means
 884 that Dovecot tries to find the mailboxes automatically.  This won't work
 885 if the user doesn't yet have any mail, so you should explicitly tell
 886 Dovecot the full location.
 887
 888 If you're using mbox, giving a path to the INBOX
 889 file (e.g. /var/mail/%u) isn't enough.  You'll also need to tell Dovecot
 890 where the other mailboxes are kept.  This is called the \"root mail
 891 directory\", and it must be the first path given in the
 892 @samp{mail-location} setting.
 893
 894 There are a few special variables you can use, eg.:
 895
 896 @table @samp
 897 @item %u
 898 username
 899 @item %n
 900 user part in user@@domain, same as %u if there's no domain
 901 @item %d
 902 domain part in user@@domain, empty if there's no domain
 903 @item %h
 904 home director
 905 @end table
 906
 907 See doc/wiki/Variables.txt for full list.  Some examples:
 908 @table @samp
 909 @item maildir:~/Maildir
 910 @item mbox:~/mail:INBOX=/var/mail/%u
 911 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
 912 @end table")
 913
 914   (mail-uid
 915    (string "")
 916    "System user and group used to access mails.  If you use multiple,
 917 userdb can override these by returning uid or gid fields.  You can use
 918 either numbers or names.  <doc/wiki/UserIds.txt>.")
 919
 920   (mail-gid
 921    (string "")
 922    "")
 923
 924   (mail-privileged-group
 925    (string "")
 926    "Group to enable temporarily for privileged operations.  Currently
 927 this is used only with INBOX when either its initial creation or
 928 dotlocking fails.  Typically this is set to \"mail\" to give access to
 929 /var/mail.")
 930
 931   (mail-access-groups
 932    (string "")
 933    "Grant access to these supplementary groups for mail processes.
 934 Typically these are used to set up access to shared mailboxes.  Note
 935 that it may be dangerous to set these if users can create
 936 symlinks (e.g. if \"mail\" group is set here, ln -s /var/mail ~/mail/var
 937 could allow a user to delete others' mailboxes, or ln -s
 938 /secret/shared/box ~/mail/mybox would allow reading it).")
 939
 940   (mail-full-filesystem-access?
 941    (boolean #f)
 942    "Allow full file system access to clients.  There's no access checks
 943 other than what the operating system does for the active UID/GID.  It
 944 works with both maildir and mboxes, allowing you to prefix mailboxes
 945 names with e.g. /path/ or ~user/.")
 946
 947 ;;; Mail processes
 948
 949   (mmap-disable?
 950    (boolean #f)
 951    "Don't use mmap() at all.  This is required if you store indexes to
 952 shared file systems (NFS or clustered file system).")
 953
 954   (dotlock-use-excl?
 955    (boolean #t)
 956    "Rely on @samp{O_EXCL} to work when creating dotlock files.  NFS
 957 supports @samp{O_EXCL} since version 3, so this should be safe to use
 958 nowadays by default.")
 959
 960   (mail-fsync
 961    (string "optimized")
 962    "When to use fsync() or fdatasync() calls:
 963 @table @code
 964 @item optimized
 965 Whenever necessary to avoid losing important data
 966 @item always
 967 Useful with e.g. NFS when write()s are delayed
 968 @item never
 969 Never use it (best performance, but crashes can lose data).
 970 @end table")
 971
 972   (mail-nfs-storage?
 973    (boolean #f)
 974    "Mail storage exists in NFS.  Set this to yes to make Dovecot flush
 975 NFS caches whenever needed.  If you're using only a single mail server
 976 this isn't needed.")
 977
 978   (mail-nfs-index?
 979    (boolean #f)
 980    "Mail index files also exist in NFS.  Setting this to yes requires
 981 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.")
 982
 983   (lock-method
 984    (string "fcntl")
 985    "Locking method for index files.  Alternatives are fcntl, flock and
 986 dotlock.  Dotlocking uses some tricks which may create more disk I/O
 987 than other locking methods.  NFS users: flock doesn't work, remember to
 988 change @samp{mmap-disable}.")
 989
 990   (mail-temp-dir
 991    (file-name "/tmp")
 992    "Directory in which LDA/LMTP temporarily stores incoming mails >128
 993 kB.")
 994
 995   (first-valid-uid
 996    (non-negative-integer 500)
 997    "Valid UID range for users.  This is mostly to make sure that users can't
 998 log in as daemons or other system users.  Note that denying root logins is
 999 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
1000 is set to 0.")
1001
1002   (last-valid-uid
1003    (non-negative-integer 0)
1004    "")
1005
1006   (first-valid-gid
1007    (non-negative-integer 1)
1008    "Valid GID range for users.  Users having non-valid GID as primary group ID
1009 aren't allowed to log in.  If user belongs to supplementary groups with
1010 non-valid GIDs, those groups are not set.")
1011
1012   (last-valid-gid
1013    (non-negative-integer 0)
1014    "")
1015
1016   (mail-max-keyword-length
1017    (non-negative-integer 50)
1018    "Maximum allowed length for mail keyword name.  It's only forced when
1019 trying to create new keywords.")
1020
1021   (valid-chroot-dirs
1022    (colon-separated-file-name-list '())
1023    "List of directories under which chrooting is allowed for mail
1024 processes (i.e. /var/mail will allow chrooting to /var/mail/foo/bar
1025 too).  This setting doesn't affect @samp{login-chroot}
1026 @samp{mail-chroot} or auth chroot settings.  If this setting is empty,
1027 \"/./\" in home dirs are ignored.  WARNING: Never add directories here
1028 which local users can modify, that may lead to root exploit.  Usually
1029 this should be done only if you don't allow shell access for users.
1030 <doc/wiki/Chrooting.txt>.")
1031
1032   (mail-chroot
1033    (string "")
1034    "Default chroot directory for mail processes.  This can be overridden
1035 for specific users in user database by giving /./ in user's home
1036 directory (e.g. /home/./user chroots into /home).  Note that usually
1037 there is no real need to do chrooting, Dovecot doesn't allow users to
1038 access files outside their mail directory anyway.  If your home
1039 directories are prefixed with the chroot directory, append \"/.\" to
1040 @samp{mail-chroot}.  <doc/wiki/Chrooting.txt>.")
1041
1042   (auth-socket-path
1043    (file-name "/var/run/dovecot/auth-userdb")
1044    "UNIX socket path to master authentication server to find users.
1045 This is used by imap (for shared users) and lda.")
1046
1047   (mail-plugin-dir
1048    (file-name "/usr/lib/dovecot")
1049    "Directory where to look up mail plugins.")
1050
1051   (mail-plugins
1052    (space-separated-string-list '())
1053    "List of plugins to load for all services.  Plugins specific to IMAP,
1054 LDA, etc. are added to this list in their own .conf files.")
1055
1056
1057   (mail-cache-min-mail-count
1058    (non-negative-integer 0)
1059    "The minimum number of mails in a mailbox before updates are done to
1060 cache file.  This allows optimizing Dovecot's behavior to do less disk
1061 writes at the cost of more disk reads.")
1062
1063   (mailbox-idle-check-interval
1064    (string "30 secs")
1065    "When IDLE command is running, mailbox is checked once in a while to
1066 see if there are any new mails or other changes.  This setting defines
1067 the minimum time to wait between those checks.  Dovecot can also use
1068 dnotify, inotify and kqueue to find out immediately when changes
1069 occur.")
1070
1071   (mail-save-crlf?
1072    (boolean #f)
1073    "Save mails with CR+LF instead of plain LF.  This makes sending those
1074 mails take less CPU, especially with sendfile() syscall with Linux and
1075 FreeBSD.  But it also creates a bit more disk I/O which may just make it
1076 slower.  Also note that if other software reads the mboxes/maildirs,
1077 they may handle the extra CRs wrong and cause problems.")
1078
1079   (maildir-stat-dirs?
1080    (boolean #f)
1081    "By default LIST command returns all entries in maildir beginning
1082 with a dot.  Enabling this option makes Dovecot return only entries
1083 which are directories.  This is done by stat()ing each entry, so it
1084 causes more disk I/O.
1085  (For systems setting struct @samp{dirent->d_type} this check is free
1086 and it's done always regardless of this setting).")
1087
1088   (maildir-copy-with-hardlinks?
1089    (boolean #t)
1090    "When copying a message, do it with hard links whenever possible.
1091 This makes the performance much better, and it's unlikely to have any
1092 side effects.")
1093
1094   (maildir-very-dirty-syncs?
1095    (boolean #f)
1096    "Assume Dovecot is the only MUA accessing Maildir: Scan cur/
1097 directory only when its mtime changes unexpectedly or when we can't find
1098 the mail otherwise.")
1099
1100   (mbox-read-locks
1101    (space-separated-string-list '("fcntl"))
1102    "Which locking methods to use for locking mbox.  There are four
1103 available:
1104
1105 @table @code
1106 @item dotlock
1107 Create <mailbox>.lock file.  This is the oldest and most NFS-safe
1108 solution.  If you want to use /var/mail/ like directory, the users will
1109 need write access to that directory.
1110 @item dotlock-try
1111 Same as dotlock, but if it fails because of permissions or because there
1112 isn't enough disk space, just skip it.
1113 @item fcntl
1114 Use this if possible.  Works with NFS too if lockd is used.
1115 @item flock
1116 May not exist in all systems.  Doesn't work with NFS.
1117 @item lockf
1118 May not exist in all systems.  Doesn't work with NFS.
1119 @end table
1120
1121 You can use multiple locking methods; if you do the order they're declared
1122 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
1123 locking methods as well.  Some operating systems don't allow using some of
1124 them simultaneously.")
1125
1126   (mbox-write-locks
1127    (space-separated-string-list '("dotlock" "fcntl"))
1128    "")
1129
1130   (mbox-lock-timeout
1131    (string "5 mins")
1132    "Maximum time to wait for lock (all of them) before aborting.")
1133
1134   (mbox-dotlock-change-timeout
1135    (string "2 mins")
1136    "If dotlock exists but the mailbox isn't modified in any way,
1137 override the lock file after this much time.")
1138
1139   (mbox-dirty-syncs?
1140    (boolean #t)
1141    "When mbox changes unexpectedly we have to fully read it to find out
1142 what changed.  If the mbox is large this can take a long time.  Since
1143 the change is usually just a newly appended mail, it'd be faster to
1144 simply read the new mails.  If this setting is enabled, Dovecot does
1145 this but still safely fallbacks to re-reading the whole mbox file
1146 whenever something in mbox isn't how it's expected to be.  The only real
1147 downside to this setting is that if some other MUA changes message
1148 flags, Dovecot doesn't notice it immediately.  Note that a full sync is
1149 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.")
1150
1151   (mbox-very-dirty-syncs?
1152    (boolean #f)
1153    "Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
1154 EXAMINE, EXPUNGE or CHECK commands.  If this is set,
1155 @samp{mbox-dirty-syncs} is ignored.")
1156
1157   (mbox-lazy-writes?
1158    (boolean #t)
1159    "Delay writing mbox headers until doing a full write sync (EXPUNGE
1160 and CHECK commands and when closing the mailbox).  This is especially
1161 useful for POP3 where clients often delete all mails.  The downside is
1162 that our changes aren't immediately visible to other MUAs.")
1163
1164   (mbox-min-index-size
1165    (non-negative-integer 0)
1166    "If mbox size is smaller than this (e.g. 100k), don't write index
1167 files.  If an index file already exists it's still read, just not
1168 updated.")
1169
1170   (mdbox-rotate-size
1171    (non-negative-integer #e10e6)
1172    "Maximum dbox file size until it's rotated.")
1173
1174   (mdbox-rotate-interval
1175    (string "1d")
1176    "Maximum dbox file age until it's rotated.  Typically in days.  Day
1177 begins from midnight, so 1d = today, 2d = yesterday, etc.  0 = check
1178 disabled.")
1179
1180   (mdbox-preallocate-space?
1181    (boolean #f)
1182    "When creating new mdbox files, immediately preallocate their size to
1183 @samp{mdbox-rotate-size}.  This setting currently works only in Linux
1184 with some file systems (ext4, xfs).")
1185
1186   (mail-attachment-dir
1187    (string "")
1188    "sdbox and mdbox support saving mail attachments to external files,
1189 which also allows single instance storage for them.  Other backends
1190 don't support this for now.
1191
1192 WARNING: This feature hasn't been tested much yet.  Use at your own risk.
1193
1194 Directory root where to store mail attachments.  Disabled, if empty.")
1195
1196   (mail-attachment-min-size
1197    (non-negative-integer #e128e3)
1198    "Attachments smaller than this aren't saved externally.  It's also
1199 possible to write a plugin to disable saving specific attachments
1200 externally.")
1201
1202   (mail-attachment-fs
1203    (string "sis posix")
1204    "File system backend to use for saving attachments:
1205 @table @code
1206 @item posix
1207 No SiS done by Dovecot (but this might help FS's own deduplication)
1208 @item sis posix
1209 SiS with immediate byte-by-byte comparison during saving
1210 @item sis-queue posix
1211 SiS with delayed comparison and deduplication.
1212 @end table")
1213
1214   (mail-attachment-hash
1215    (string "%{sha1}")
1216    "Hash format to use in attachment filenames.  You can add any text and
1217 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
1218 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}.  Variables can be
1219 truncated, e.g. @code{%@{sha256:80@}} returns only first 80 bits.")
1220
1221   (default-process-limit
1222     (non-negative-integer 100)
1223     "")
1224
1225   (default-client-limit
1226     (non-negative-integer 1000)
1227     "")
1228
1229   (default-vsz-limit
1230     (non-negative-integer #e256e6)
1231     "Default VSZ (virtual memory size) limit for service processes.
1232 This is mainly intended to catch and kill processes that leak memory
1233 before they eat up everything.")
1234
1235   (default-login-user
1236     (string "dovenull")
1237     "Login user is internally used by login processes.  This is the most
1238 untrusted user in Dovecot system.  It shouldn't have access to anything
1239 at all.")
1240
1241   (default-internal-user
1242     (string "dovecot")
1243     "Internal user is used by unprivileged processes.  It should be
1244 separate from login user, so that login processes can't disturb other
1245 processes.")
1246
1247   (ssl?
1248    (string "required")
1249    "SSL/TLS support: yes, no, required.  <doc/wiki/SSL.txt>.")
1250
1251   (ssl-cert
1252    (string "</etc/dovecot/default.pem")
1253    "PEM encoded X.509 SSL/TLS certificate (public key).")
1254
1255   (ssl-key
1256    (string "</etc/dovecot/private/default.pem")
1257    "PEM encoded SSL/TLS private key.  The key is opened before
1258 dropping root privileges, so keep the key file unreadable by anyone but
1259 root.")
1260
1261   (ssl-key-password
1262    (string "")
1263    "If key file is password protected, give the password here.
1264 Alternatively give it when starting dovecot with -p parameter.  Since
1265 this file is often world-readable, you may want to place this setting
1266 instead to a different.")
1267
1268   (ssl-ca
1269    (string "")
1270    "PEM encoded trusted certificate authority.  Set this only if you
1271 intend to use @samp{ssl-verify-client-cert? #t}.  The file should
1272 contain the CA certificate(s) followed by the matching
1273 CRL(s).  (e.g. @samp{ssl-ca </etc/ssl/certs/ca.pem}).")
1274   (ssl-require-crl?
1275    (boolean #t)
1276    "Require that CRL check succeeds for client certificates.")
1277   (ssl-verify-client-cert?
1278    (boolean #f)
1279    "Request client to send a certificate.  If you also want to require
1280 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.")
1281
1282   (ssl-cert-username-field
1283    (string "commonName")
1284    "Which field from certificate to use for username.  commonName and
1285 x500UniqueIdentifier are the usual choices.  You'll also need to set
1286 @samp{auth-ssl-username-from-cert? #t}.")
1287
1288   (ssl-min-protocol
1289    (string "TLSv1")
1290    "Minimum SSL protocol version to accept.")
1291
1292   (ssl-cipher-list
1293    (string "ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@STRENGTH")
1294    "SSL ciphers to use.")
1295
1296   (ssl-crypto-device
1297    (string "")
1298    "SSL crypto device to use, for valid values run \"openssl engine\".")
1299
1300   (postmaster-address
1301    (string "postmaster@%d")
1302    "Address to use when sending rejection mails.
1303 Default is postmaster@@<your domain>.  %d expands to recipient domain.")
1304
1305   (hostname
1306    (string "")
1307    "Hostname to use in various parts of sent mails (e.g. in Message-Id)
1308 and in LMTP replies.  Default is the system's real hostname@@domain.")
1309
1310   (quota-full-tempfail?
1311    (boolean #f)
1312    "If user is over quota, return with temporary failure instead of
1313 bouncing the mail.")
1314
1315   (sendmail-path
1316    (file-name "/usr/sbin/sendmail")
1317    "Binary to use for sending mails.")
1318
1319   (submission-host
1320    (string "")
1321    "If non-empty, send mails via this SMTP host[:port] instead of
1322 sendmail.")
1323
1324   (rejection-subject
1325    (string "Rejected: %s")
1326    "Subject: header to use for rejection mails.  You can use the same
1327 variables as for @samp{rejection-reason} below.")
1328
1329   (rejection-reason
1330    (string "Your message to <%t> was automatically rejected:%n%r")
1331    "Human readable error message for rejection mails.  You can use
1332 variables:
1333
1334 @table @code
1335 @item %n
1336 CRLF
1337 @item %r
1338 reason
1339 @item %s
1340 original subject
1341 @item %t
1342 recipient
1343 @end table")
1344
1345   (recipient-delimiter
1346    (string "+")
1347    "Delimiter character between local-part and detail in email
1348 address.")
1349
1350   (lda-original-recipient-header
1351    (string "")
1352    "Header where the original recipient address (SMTP's RCPT TO:
1353 address) is taken from if not available elsewhere.  With dovecot-lda -a
1354 parameter overrides this.  A commonly used header for this is
1355 X-Original-To.")
1356
1357   (lda-mailbox-autocreate?
1358    (boolean #f)
1359    "Should saving a mail to a nonexistent mailbox automatically create
1360 it?.")
1361
1362   (lda-mailbox-autosubscribe?
1363    (boolean #f)
1364    "Should automatically created mailboxes be also automatically
1365 subscribed?.")
1366
1367
1368   (imap-max-line-length
1369    (non-negative-integer #e64e3)
1370    "Maximum IMAP command line length.  Some clients generate very long
1371 command lines with huge mailboxes, so you may need to raise this if you
1372 get \"Too long argument\" or \"IMAP command line too large\" errors
1373 often.")
1374
1375   (imap-logout-format
1376    (string "in=%i out=%o deleted=%{deleted} expunged=%{expunged} trashed=%{trashed} hdr_count=%{fetch_hdr_count} hdr_bytes=%{fetch_hdr_bytes} body_count=%{fetch_body_count} body_bytes=%{fetch_body_bytes}")
1377    "IMAP logout format string:
1378 @table @code
1379 @item %i
1380 total number of bytes read from client
1381 @item %o
1382 total number of bytes sent to client.
1383 @end table
1384 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.")
1385
1386   (imap-capability
1387    (string "")
1388    "Override the IMAP CAPABILITY response.  If the value begins with '+',
1389 add the given capabilities on top of the defaults (e.g. +XFOO XBAR).")
1390
1391   (imap-idle-notify-interval
1392    (string "2 mins")
1393    "How long to wait between \"OK Still here\" notifications when client
1394 is IDLEing.")
1395
1396   (imap-id-send
1397    (string "")
1398    "ID field names and values to send to clients.  Using * as the value
1399 makes Dovecot use the default value.  The following fields have default
1400 values currently: name, version, os, os-version, support-url,
1401 support-email.")
1402
1403   (imap-id-log
1404    (string "")
1405    "ID fields sent by client to log.  * means everything.")
1406
1407   (imap-client-workarounds
1408    (space-separated-string-list '())
1409    "Workarounds for various client bugs:
1410
1411 @table @code
1412 @item delay-newmail
1413 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
1414 CHECK commands.  Some clients ignore them otherwise, for example OSX
1415 Mail (<v2.1).  Outlook Express breaks more badly though, without this it
1416 may show user \"Message no longer in server\" errors.  Note that OE6
1417 still breaks even with this workaround if synchronization is set to
1418 \"Headers Only\".
1419
1420 @item tb-extra-mailbox-sep
1421 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
1422 adds extra @samp{/} suffixes to mailbox names.  This option causes Dovecot to
1423 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
1424
1425 @item tb-lsub-flags
1426 Show \\Noselect flags for LSUB replies with LAYOUT=fs (e.g. mbox).
1427 This makes Thunderbird realize they aren't selectable and show them
1428 greyed out, instead of only later giving \"not selectable\" popup error.
1429 @end table
1430 ")
1431
1432   (imap-urlauth-host
1433    (string "")
1434    "Host allowed in URLAUTH URLs sent by client.  \"*\" allows all.")  )
1435
1436 (define-configuration opaque-dovecot-configuration
1437   (dovecot
1438    (package dovecot)
1439    "The dovecot package.")
1440
1441   (string
1442    (string (configuration-missing-field 'opaque-dovecot-configuration
1443                                         'string))
1444    "The contents of the @code{dovecot.conf} to use."))
1445
1446 (define %dovecot-accounts
1447   ;; Account and group for the Dovecot daemon.
1448   (list (user-group (name "dovecot") (system? #t))
1449         (user-account
1450          (name "dovecot")
1451          (group "dovecot")
1452          (system? #t)
1453          (comment "Dovecot daemon user")
1454          (home-directory "/var/empty")
1455          (shell (file-append shadow "/sbin/nologin")))
1456
1457         (user-group (name "dovenull") (system? #t))
1458         (user-account
1459          (name "dovenull")
1460          (group "dovenull")
1461          (system? #t)
1462          (comment "Dovecot daemon login user")
1463          (home-directory "/var/empty")
1464          (shell (file-append shadow "/sbin/nologin")))))
1465
1466 (define (%dovecot-activation config)
1467   ;; Activation gexp.
1468   (let ((config-str
1469          (cond
1470           ((opaque-dovecot-configuration? config)
1471            (opaque-dovecot-configuration-string config))
1472           (else
1473            (with-output-to-string
1474              (lambda ()
1475                (serialize-configuration config
1476                                         dovecot-configuration-fields)))))))
1477     #~(begin
1478         (use-modules (guix build utils))
1479         (define (mkdir-p/perms directory owner perms)
1480           (mkdir-p directory)
1481           (chown "/var/run/dovecot" (passwd:uid owner) (passwd:gid owner))
1482           (chmod directory perms))
1483         (define (build-subject parameters)
1484           (string-concatenate
1485            (map (lambda (pair)
1486                   (let ((k (car pair)) (v (cdr pair)))
1487                     (define (escape-char str chr)
1488                       (string-join (string-split str chr) (string #\\ chr)))
1489                     (string-append "/" k "="
1490                                    (escape-char (escape-char v #\=) #\/))))
1491                 (filter (lambda (pair) (cdr pair)) parameters))))
1492         (define* (create-self-signed-certificate-if-absent
1493                   #:key private-key public-key (owner (getpwnam "root"))
1494                   (common-name (gethostname))
1495                   (organization-name "GuixSD")
1496                   (organization-unit-name "Default Self-Signed Certificate")
1497                   (subject-parameters `(("CN" . ,common-name)
1498                                         ("O" . ,organization-name)
1499                                         ("OU" . ,organization-unit-name)))
1500                   (subject (build-subject subject-parameters)))
1501           ;; Note that by default, OpenSSL outputs keys in PEM format.  This
1502           ;; is what we want.
1503           (unless (file-exists? private-key)
1504             (cond
1505              ((zero? (system* (string-append #$openssl "/bin/openssl")
1506                               "genrsa" "-out" private-key "2048"))
1507               (chown private-key (passwd:uid owner) (passwd:gid owner))
1508               (chmod private-key #o400))
1509              (else
1510               (format (current-error-port)
1511                       "Failed to create private key at ~a.\n" private-key))))
1512           (unless (file-exists? public-key)
1513             (cond
1514              ((zero? (system* (string-append #$openssl "/bin/openssl")
1515                               "req" "-new" "-x509" "-key" private-key
1516                               "-out" public-key "-days" "3650"
1517                               "-batch" "-subj" subject))
1518               (chown public-key (passwd:uid owner) (passwd:gid owner))
1519               (chmod public-key #o444))
1520              (else
1521               (format (current-error-port)
1522                       "Failed to create public key at ~a.\n" public-key)))))
1523         (let ((user (getpwnam "dovecot")))
1524           (mkdir-p/perms "/var/run/dovecot" user #o755)
1525           (mkdir-p/perms "/var/lib/dovecot" user #o755)
1526           (mkdir-p/perms "/etc/dovecot" user #o755)
1527           (copy-file #$(plain-file "dovecot.conf" config-str)
1528                      "/etc/dovecot/dovecot.conf")
1529           (mkdir-p/perms "/etc/dovecot/private" user #o700)
1530           (create-self-signed-certificate-if-absent
1531            #:private-key "/etc/dovecot/private/default.pem"
1532            #:public-key "/etc/dovecot/default.pem"
1533            #:owner (getpwnam "root")
1534            #:common-name (format #f "Dovecot service on ~a" (gethostname)))))))
1535
1536 (define (dovecot-shepherd-service config)
1537   "Return a list of <shepherd-service> for CONFIG."
1538   (let ((dovecot (if (opaque-dovecot-configuration? config)
1539                      (opaque-dovecot-configuration-dovecot config)
1540                      (dovecot-configuration-dovecot config))))
1541     (list (shepherd-service
1542            (documentation "Run the Dovecot POP3/IMAP mail server.")
1543            (provision '(dovecot))
1544            (requirement '(networking))
1545            (start #~(make-forkexec-constructor
1546                      (list (string-append #$dovecot "/sbin/dovecot")
1547                            "-F")))
1548            (stop #~(make-forkexec-constructor
1549                     (list (string-append #$dovecot "/sbin/dovecot")
1550                           "stop")))))))
1551
1552 (define %dovecot-pam-services
1553   (list (unix-pam-service "dovecot")))
1554
1555 (define dovecot-service-type
1556   (service-type (name 'dovecot)
1557                 (extensions
1558                  (list (service-extension shepherd-root-service-type
1559                                           dovecot-shepherd-service)
1560                        (service-extension account-service-type
1561                                           (const %dovecot-accounts))
1562                        (service-extension pam-root-service-type
1563                                           (const %dovecot-pam-services))
1564                        (service-extension activation-service-type
1565                                           %dovecot-activation)))))
1566
1567 (define* (dovecot-service #:key (config (dovecot-configuration)))
1568   "Return a service that runs @command{dovecot}, a mail server that can run
1569 POP3, IMAP, and LMTP.  @var{config} should be a configuration object created
1570 by @code{dovecot-configuration}.  @var{config} may also be created by
1571 @code{opaque-dovecot-configuration}, which allows specification of the
1572 @code{dovecot.conf} as a string."
1573   (validate-configuration config
1574                           (if (opaque-dovecot-configuration? config)
1575                               opaque-dovecot-configuration-fields
1576                               dovecot-configuration-fields))
1577   (service dovecot-service-type config))
1578
1579 ;; A little helper to make it easier to document all those fields.
1580 (define (generate-dovecot-documentation)
1581   (generate-documentation
1582     `((dovecot-configuration
1583        ,dovecot-configuration-fields
1584        (dict dict-configuration)
1585        (namespaces namespace-configuration)
1586        (plugin plugin-configuration)
1587        (passdbs passdb-configuration)
1588        (userdbs userdb-configuration)
1589        (services service-configuration)
1590        (protocols protocol-configuration))
1591       (dict-configuration ,dict-configuration-fields)
1592       (plugin-configuration ,plugin-configuration-fields)
1593       (passdb-configuration ,passdb-configuration-fields)
1594       (userdb-configuration ,userdb-configuration-fields)
1595       (unix-listener-configuration ,unix-listener-configuration-fields)
1596       (fifo-listener-configuration ,fifo-listener-configuration-fields)
1597       (inet-listener-configuration ,inet-listener-configuration-fields)
1598       (namespace-configuration
1599        ,namespace-configuration-fields
1600        (mailboxes mailbox-configuration))
1601       (mailbox-configuration ,mailbox-configuration-fields)
1602       (service-configuration
1603        ,service-configuration-fields
1604        (listeners unix-listener-configuration fifo-listener-configuration
1605                   inet-listener-configuration))
1606       (protocol-configuration ,protocol-configuration-fields))
1607   'dovecot-configuration))
1608
1609 \f
1610 ;;;
1611 ;;; OpenSMTPD.
1612 ;;;
1613
1614 (define-record-type* <opensmtpd-configuration>
1615   opensmtpd-configuration make-opensmtpd-configuration
1616   opensmtpd-configuration?
1617   (package     opensmtpd-configuration-package
1618                (default opensmtpd))
1619   (config-file opensmtpd-configuration-config-file
1620                (default %default-opensmtpd-config-file)))
1621
1622 (define %default-opensmtpd-config-file
1623   (plain-file "smtpd.conf" "
1624 listen on lo
1625 accept from any for local deliver to mbox
1626 accept from local for any relay
1627 "))
1628
1629 (define opensmtpd-shepherd-service
1630   (match-lambda
1631     (($ <opensmtpd-configuration> package config-file)
1632      (list (shepherd-service
1633             (provision '(smtpd))
1634             (requirement '(loopback))
1635             (documentation "Run the OpenSMTPD daemon.")
1636             (start (let ((smtpd (file-append package "/sbin/smtpd")))
1637                      #~(make-forkexec-constructor
1638                         (list #$smtpd "-f" #$config-file)
1639                         #:pid-file "/var/run/smtpd.pid")))
1640             (stop #~(make-kill-destructor)))))))
1641
1642 (define %opensmtpd-accounts
1643   (list (user-group
1644          (name "smtpq")
1645          (system? #t))
1646         (user-account
1647          (name "smtpd")
1648          (group "nogroup")
1649          (system? #t)
1650          (comment "SMTP Daemon")
1651          (home-directory "/var/empty")
1652          (shell (file-append shadow "/sbin/nologin")))
1653         (user-account
1654          (name "smtpq")
1655          (group "smtpq")
1656          (system? #t)
1657          (comment "SMTPD Queue")
1658          (home-directory "/var/empty")
1659          (shell (file-append shadow "/sbin/nologin")))))
1660
1661 (define opensmtpd-activation
1662   (match-lambda
1663     (($ <opensmtpd-configuration> package config-file)
1664      (let ((smtpd (file-append package "/sbin/smtpd")))
1665        #~(begin
1666            (use-modules (guix build utils))
1667            ;; Create mbox and spool directories.
1668            (mkdir-p "/var/mail")
1669            (mkdir-p "/var/spool/smtpd")
1670            (chmod "/var/spool/smtpd" #o711))))))
1671
1672 (define opensmtpd-service-type
1673   (service-type
1674    (name 'opensmtpd)
1675    (extensions
1676     (list (service-extension account-service-type
1677                              (const %opensmtpd-accounts))
1678           (service-extension activation-service-type
1679                              opensmtpd-activation)
1680           (service-extension profile-service-type
1681                              (compose list opensmtpd-configuration-package))
1682           (service-extension shepherd-root-service-type
1683                              opensmtpd-shepherd-service)))))
1684
1685 \f
1686 ;;;
1687 ;;; mail aliases.
1688 ;;;
1689
1690 (define (mail-aliases-etc aliases)
1691   `(("aliases" ,(plain-file "aliases"
1692                             ;; Ideally we'd use a format string like
1693                             ;; "~:{~a: ~{~a~^,~}\n~}", but it gives a
1694                             ;; warning that I can't figure out how to fix,
1695                             ;; so we'll just use string-join below instead.
1696                             (format #f "~:{~a: ~a\n~}"
1697                                     (map (match-lambda
1698                                            ((alias addresses ...)
1699                                             (list alias (string-join addresses ","))))
1700                                          aliases))))))
1701
1702 (define mail-aliases-service-type
1703   (service-type
1704    (name 'mail-aliases)
1705    (extensions
1706     (list (service-extension etc-service-type mail-aliases-etc)))
1707    (compose concatenate)
1708    (extend append)))
1709
1710 \f
1711 ;;;
1712 ;;; Exim.
1713 ;;;
1714
1715 (define-record-type* <exim-configuration> exim-configuration
1716   make-exim-configuration
1717   exim-configuration?
1718   (package       exim-configuration-package ;<package>
1719                  (default exim))
1720   (config-file   exim-configuration-config-file ;file-like
1721                  (default #f)))
1722
1723 (define %exim-accounts
1724   (list (user-group
1725          (name "exim")
1726          (system? #t))
1727         (user-account
1728          (name "exim")
1729          (group "exim")
1730          (system? #t)
1731          (comment "Exim Daemon")
1732          (home-directory "/var/empty")
1733          (shell (file-append shadow "/sbin/nologin")))))
1734
1735 (define (exim-computed-config-file package config-file)
1736   (computed-file "exim.conf"
1737                  #~(call-with-output-file #$output
1738                      (lambda (port)
1739                        (format port "
1740 exim_user = exim
1741 exim_group = exim
1742 .include ~a"
1743                                #$(or config-file
1744                                      (file-append package "/etc/exim.conf")))))))
1745
1746 (define exim-shepherd-service
1747   (match-lambda
1748     (($ <exim-configuration> package config-file)
1749      (list (shepherd-service
1750             (provision '(exim mta))
1751             (documentation "Run the exim daemon.")
1752             (requirement '(networking))
1753             (start #~(make-forkexec-constructor
1754                       '(#$(file-append package "/bin/exim")
1755                         "-bd" "-v" "-C"
1756                         #$(exim-computed-config-file package config-file))))
1757             (stop #~(make-kill-destructor)))))))
1758
1759 (define exim-activation
1760   (match-lambda
1761     (($ <exim-configuration> package config-file)
1762      (with-imported-modules '((guix build utils))
1763        #~(begin
1764            (use-modules (guix build utils))
1765
1766            (let ((uid (passwd:uid (getpw "exim")))
1767                  (gid (group:gid (getgr "exim"))))
1768              (mkdir-p "/var/spool/exim")
1769              (chown "/var/spool/exim" uid gid))
1770
1771            (zero? (system* #$(file-append package "/bin/exim")
1772                            "-bV" "-C" #$(exim-computed-config-file package config-file))))))))
1773
1774 (define exim-profile
1775   (compose list exim-configuration-package))
1776
1777 (define exim-service-type
1778   (service-type
1779    (name 'exim)
1780    (extensions
1781     (list (service-extension shepherd-root-service-type exim-shepherd-service)
1782           (service-extension account-service-type (const %exim-accounts))
1783           (service-extension activation-service-type exim-activation)
1784           (service-extension profile-service-type exim-profile)
1785           (service-extension mail-aliases-service-type (const '()))))))