Ansible role for a basic dovecot instance added.

Signed-off-by: Birin Sanchez <birin.sanchez@puri.sm>

playbooks/ldh_dovecot.yml

+---
+- name: Simple Dovecot role for Keel/LDH
+  hosts: all
+  become: yes
+  roles:
+    - role: ldh_dovecot
+  vars:
+    ldh_dovecot_ldap_uri: "ldap://ldap.freedom.test:389"
+    ldh_dovecot_ldap_base: "dc=freedom,dc=test"

playbooks/ldh_dovecot/README.md

+LDH Dovecot
+===========
+
+Role used to install con configure [Dovecot](https://dovecot.org/) to
+work with Keel/LDH LDAP. It includes these basic functionalities:
+
+* Virtual users from LDAP.
+* Non encrypted communication between Dovecot and LDAP.
+* `mbox` type mail boxes stored in `/var/mail` and accessed by `mail`
+  user.
+* No LDAP admin user needed for look-ups.
+
+Requirements
+------------
+
+This role has only been tested with Ansible 2.7.1.
+
+Role Variables
+--------------
+
+* `ldh_dovecot_ldap_uri`
+
+    URI used by Dovecot to connect to the LDAP server. Default value:
+    `ldap://ldap.freedom.test:389`.
+
+* `ldh_dovecot_ldap_base`
+
+    Search starting point used by Dovecot when querying the
+    LDAP instance. Default value: `dc=freedom,dc=test`.
+
+Dependencies
+------------
+
+This roles does not depend on other roles.
+
+
+License
+-------
+
+AGPL-3.0-or-later
+
+Author Information
+------------------
+
+Purism SPC <liberty@puri.sm>
+
+Homepage: https://source.puri.sm/liberty/ldh_developer

playbooks/ldh_dovecot/defaults/main.yml

+---
+# defaults file for ldh_dovecot
+ldh_dovecot_required_pkgs:
+  - dovecot-imapd
+  - dovecot-pop3d
+  - dovecot-ldap
+
+ldh_dovecot_ldap_uri: "ldap://ldap.example.com:389"
+ldh_dovecot_ldap_base: "dc=example,dc=com"

playbooks/ldh_dovecot/files/etc/dovecot/conf.d/10-auth.conf

+##
+## Authentication processes
+##
+
+# Disable LOGIN command and all other plaintext authentications unless
+# SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
+# matches the local IP (ie. you're connecting from the same computer), the
+# connection is considered secure and plaintext authentication is allowed.
+# See also ssl=required setting.
+disable_plaintext_auth = no
+
+# Authentication cache size (e.g. 10M). 0 means it's disabled. Note that
+# bsdauth, PAM and vpopmail require cache_key to be set for caching to be used.
+#auth_cache_size = 0
+# Time to live for cached data. After TTL expires the cached record is no
+# longer used, *except* if the main database lookup returns internal failure.
+# We also try to handle password changes automatically: If user's previous
+# authentication was successful, but this one wasn't, the cache isn't used.
+# For now this works only with plaintext authentication.
+#auth_cache_ttl = 1 hour
+# TTL for negative hits (user not found, password mismatch).
+# 0 disables caching them completely.
+#auth_cache_negative_ttl = 1 hour
+
+# Space separated list of realms for SASL authentication mechanisms that need
+# them. You can leave it empty if you don't want to support multiple realms.
+# Many clients simply use the first one listed here, so keep the default realm
+# first.
+#auth_realms =
+
+# Default realm/domain to use if none was specified. This is used for both
+# SASL realms and appending @domain to username in plaintext logins.
+#auth_default_realm = 
+
+# List of allowed characters in username. If the user-given username contains
+# a character not listed in here, the login automatically fails. This is just
+# an extra check to make sure user can't exploit any potential quote escaping
+# vulnerabilities with SQL/LDAP databases. If you want to allow all characters,
+# set this value to empty.
+#auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@
+
+# Username character translations before it's looked up from databases. The
+# value contains series of from -> to characters. For example "#@/@" means
+# that '#' and '/' characters are translated to '@'.
+#auth_username_translation =
+
+# Username formatting before it's looked up from databases. You can use
+# the standard variables here, eg. %Lu would lowercase the username, %n would
+# drop away the domain if it was given, or "%n-AT-%d" would change the '@' into
+# "-AT-". This translation is done after auth_username_translation changes.
+#auth_username_format = %Lu
+
+# If you want to allow master users to log in by specifying the master
+# username within the normal username string (ie. not using SASL mechanism's
+# support for it), you can specify the separator character here. The format
+# is then <username><separator><master username>. UW-IMAP uses "*" as the
+# separator, so that could be a good choice.
+#auth_master_user_separator =
+
+# Username to use for users logging in with ANONYMOUS SASL mechanism
+#auth_anonymous_username = anonymous
+
+# Maximum number of dovecot-auth worker processes. They're used to execute
+# blocking passdb and userdb queries (eg. MySQL and PAM). They're
+# automatically created and destroyed as needed.
+#auth_worker_max_count = 30
+
+# Host name to use in GSSAPI principal names. The default is to use the
+# name returned by gethostname(). Use "$ALL" (with quotes) to allow all keytab
+# entries.
+#auth_gssapi_hostname =
+
+# Kerberos keytab to use for the GSSAPI mechanism. Will use the system
+# default (usually /etc/krb5.keytab) if not specified. You may need to change
+# the auth service to run as root to be able to read this file.
+#auth_krb5_keytab = 
+
+# Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon and
+# ntlm_auth helper. <doc/wiki/Authentication/Mechanisms/Winbind.txt>
+#auth_use_winbind = no
+
+# Path for Samba's ntlm_auth helper binary.
+#auth_winbind_helper_path = /usr/bin/ntlm_auth
+
+# Time to delay before replying to failed authentications.
+#auth_failure_delay = 2 secs
+
+# Require a valid SSL client certificate or the authentication fails.
+#auth_ssl_require_client_cert = no
+
+# Take the username from client's SSL certificate, using 
+# X509_NAME_get_text_by_NID() which returns the subject's DN's
+# CommonName. 
+#auth_ssl_username_from_cert = no
+
+# Space separated list of wanted authentication mechanisms:
+#   plain login digest-md5 cram-md5 ntlm rpa apop anonymous gssapi otp skey
+#   gss-spnego
+# NOTE: See also disable_plaintext_auth setting.
+auth_mechanisms = plain
+
+##
+## Password and user databases
+##
+
+#
+# Password database is used to verify user's password (and nothing more).
+# You can have multiple passdbs and userdbs. This is useful if you want to
+# allow both system users (/etc/passwd) and virtual users to login without
+# duplicating the system users into virtual database.
+#
+# <doc/wiki/PasswordDatabase.txt>
+#
+# User database specifies where mails are located and what user/group IDs
+# own them. For single-UID configuration use "static" userdb.
+#
+# <doc/wiki/UserDatabase.txt>
+
+#!include auth-deny.conf.ext
+#!include auth-master.conf.ext
+
+#!include auth-system.conf.ext
+#!include auth-sql.conf.ext
+!include auth-ldap.conf.ext
+#!include auth-passwdfile.conf.ext
+#!include auth-checkpassword.conf.ext
+#!include auth-vpopmail.conf.ext
+#!include auth-static.conf.ext

playbooks/ldh_dovecot/files/etc/dovecot/conf.d/10-mail.conf

+##
+## Mailbox locations and namespaces
+##
+
+# Location for users' mailboxes. The default is empty, which means that Dovecot
+# tries to find the mailboxes automatically. This won't work if the user
+# doesn't yet have any mail, so you should explicitly tell Dovecot the full
+# location.
+#
+# If you're using mbox, giving a path to the INBOX file (eg. /var/mail/%u)
+# isn't enough. You'll also need to tell Dovecot where the other mailboxes are
+# kept. This is called the "root mail directory", and it must be the first
+# path given in the mail_location setting.
+#
+# There are a few special variables you can use, eg.:
+#
+#   %u - username
+#   %n - user part in user@domain, same as %u if there's no domain
+#   %d - domain part in user@domain, empty if there's no domain
+#   %h - home directory
+#
+# See doc/wiki/Variables.txt for full list. Some examples:
+#
+#   mail_location = maildir:~/Maildir
+#   mail_location = mbox:~/mail:INBOX=/var/mail/%u
+#   mail_location = mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%n
+#
+# <doc/wiki/MailLocation.txt>
+#
+mail_location = mbox:~/mail:INBOX=/var/mail/%u
+
+# If you need to set multiple mailbox locations or want to change default
+# namespace settings, you can do it by defining namespace sections.
+#
+# You can have private, shared and public namespaces. Private namespaces
+# are for user's personal mails. Shared namespaces are for accessing other
+# users' mailboxes that have been shared. Public namespaces are for shared
+# mailboxes that are managed by sysadmin. If you create any shared or public
+# namespaces you'll typically want to enable ACL plugin also, otherwise all
+# users can access all the shared mailboxes, assuming they have permissions
+# on filesystem level to do so.
+namespace inbox {
+  # Namespace type: private, shared or public
+  #type = private
+
+  # Hierarchy separator to use. You should use the same separator for all
+  # namespaces or some clients get confused. '/' is usually a good one.
+  # The default however depends on the underlying mail storage format.
+  #separator = 
+
+  # Prefix required to access this namespace. This needs to be different for
+  # all namespaces. For example "Public/".
+  #prefix = 
+
+  # Physical location of the mailbox. This is in same format as
+  # mail_location, which is also the default for it.
+  #location =
+
+  # There can be only one INBOX, and this setting defines which namespace
+  # has it.
+  inbox = yes
+
+  # If namespace is hidden, it's not advertised to clients via NAMESPACE
+  # extension. You'll most likely also want to set list=no. This is mostly
+  # useful when converting from another server with different namespaces which
+  # you want to deprecate but still keep working. For example you can create
+  # hidden namespaces with prefixes "~/mail/", "~%u/mail/" and "mail/".
+  #hidden = no
+
+  # Show the mailboxes under this namespace with LIST command. This makes the
+  # namespace visible for clients that don't support NAMESPACE extension.
+  # "children" value lists child mailboxes, but hides the namespace prefix.
+  #list = yes
+
+  # Namespace handles its own subscriptions. If set to "no", the parent
+  # namespace handles them (empty prefix should always have this as "yes")
+  #subscriptions = yes
+
+  # See 15-mailboxes.conf for definitions of special mailboxes.
+}
+
+# Example shared namespace configuration
+#namespace {
+  #type = shared
+  #separator = /
+
+  # Mailboxes are visible under "shared/user@domain/"
+  # %%n, %%d and %%u are expanded to the destination user.
+  #prefix = shared/%%u/
+
+  # Mail location for other users' mailboxes. Note that %variables and ~/
+  # expands to the logged in user's data. %%n, %%d, %%u and %%h expand to the
+  # destination user's data.
+  #location = maildir:%%h/Maildir:INDEX=~/Maildir/shared/%%u
+
+  # Use the default namespace for saving subscriptions.
+  #subscriptions = no
+
+  # List the shared/ namespace only if there are visible shared mailboxes.
+  #list = children
+#}
+# Should shared INBOX be visible as "shared/user" or "shared/user/INBOX"?
+#mail_shared_explicit_inbox = no
+
+# System user and group used to access mails. If you use multiple, userdb
+# can override these by returning uid or gid fields. You can use either numbers
+# or names. <doc/wiki/UserIds.txt>
+#mail_uid =
+#mail_gid =
+
+# Group to enable temporarily for privileged operations. Currently this is
+# used only with INBOX when either its initial creation or dotlocking fails.
+# Typically this is set to "mail" to give access to /var/mail.
+mail_privileged_group = mail
+
+# Grant access to these supplementary groups for mail processes. Typically
+# these are used to set up access to shared mailboxes. Note that it may be
+# dangerous to set these if users can create symlinks (e.g. if "mail" group is
+# set here, ln -s /var/mail ~/mail/var could allow a user to delete others'
+# mailboxes, or ln -s /secret/shared/box ~/mail/mybox would allow reading it).
+#mail_access_groups =
+
+# Allow full filesystem access to clients. There's no access checks other than
+# what the operating system does for the active UID/GID. It works with both
+# maildir and mboxes, allowing you to prefix mailboxes names with eg. /path/
+# or ~user/.
+#mail_full_filesystem_access = no
+
+# Dictionary for key=value mailbox attributes. This is used for example by
+# URLAUTH and METADATA extensions.
+#mail_attribute_dict =
+
+# A comment or note that is associated with the server. This value is
+# accessible for authenticated users through the IMAP METADATA server
+# entry "/shared/comment". 
+#mail_server_comment = ""
+
+# Indicates a method for contacting the server administrator. According to
+# RFC 5464, this value MUST be a URI (e.g., a mailto: or tel: URL), but that
+# is currently not enforced. Use for example mailto:admin@example.com. This
+# value is accessible for authenticated users through the IMAP METADATA server
+# entry "/shared/admin".
+#mail_server_admin = 
+
+##
+## Mail processes
+##
+
+# Don't use mmap() at all. This is required if you store indexes to shared
+# filesystems (NFS or clustered filesystem).
+#mmap_disable = no
+
+# Rely on O_EXCL to work when creating dotlock files. NFS supports O_EXCL
+# since version 3, so this should be safe to use nowadays by default.
+#dotlock_use_excl = yes
+
+# When to use fsync() or fdatasync() calls:
+#   optimized (default): Whenever necessary to avoid losing important data
+#   always: Useful with e.g. NFS when write()s are delayed
+#   never: Never use it (best performance, but crashes can lose data)
+#mail_fsync = optimized
+
+# Locking method for index files. Alternatives are fcntl, flock and dotlock.
+# Dotlocking uses some tricks which may create more disk I/O than other locking
+# methods. NFS users: flock doesn't work, remember to change mmap_disable.
+#lock_method = fcntl
+
+# Directory in which LDA/LMTP temporarily stores incoming mails >128 kB.
+#mail_temp_dir = /tmp
+
+# Valid UID range for users, defaults to 500 and above. This is mostly
+# to make sure that users can't log in as daemons or other system users.
+# Note that denying root logins is hardcoded to dovecot binary and can't
+# be done even if first_valid_uid is set to 0.
+first_valid_uid = 8
+#last_valid_uid = 0
+
+# Valid GID range for users, defaults to non-root/wheel. Users having
+# non-valid GID as primary group ID aren't allowed to log in. If user
+# belongs to supplementary groups with non-valid GIDs, those groups are
+# not set.
+#first_valid_gid = 1
+#last_valid_gid = 0
+
+# Maximum allowed length for mail keyword name. It's only forced when trying
+# to create new keywords.
+#mail_max_keyword_length = 50
+
+# ':' separated list of directories under which chrooting is allowed for mail
+# processes (ie. /var/mail will allow chrooting to /var/mail/foo/bar too).
+# This setting doesn't affect login_chroot, mail_chroot or auth chroot
+# settings. If this setting is empty, "/./" in home dirs are ignored.
+# WARNING: Never add directories here which local users can modify, that
+# may lead to root exploit. Usually this should be done only if you don't
+# allow shell access for users. <doc/wiki/Chrooting.txt>
+#valid_chroot_dirs = 
+
+# Default chroot directory for mail processes. This can be overridden for
+# specific users in user database by giving /./ in user's home directory
+# (eg. /home/./user chroots into /home). Note that usually there is no real
+# need to do chrooting, Dovecot doesn't allow users to access files outside
+# their mail directory anyway. If your home directories are prefixed with
+# the chroot directory, append "/." to mail_chroot. <doc/wiki/Chrooting.txt>
+#mail_chroot = 
+
+# UNIX socket path to master authentication server to find users.
+# This is used by imap (for shared users) and lda.
+#auth_socket_path = /var/run/dovecot/auth-userdb
+
+# Directory where to look up mail plugins.
+#mail_plugin_dir = /usr/lib/dovecot/modules
+
+# Space separated list of plugins to load for all services. Plugins specific to
+# IMAP, LDA, etc. are added to this list in their own .conf files.
+#mail_plugins = 
+
+##
+## Mailbox handling optimizations
+##
+
+# Mailbox list indexes can be used to optimize IMAP STATUS commands. They are
+# also required for IMAP NOTIFY extension to be enabled.
+#mailbox_list_index = no
+
+# The minimum number of mails in a mailbox before updates are done to cache
+# file. This allows optimizing Dovecot's behavior to do less disk writes at
+# the cost of more disk reads.
+#mail_cache_min_mail_count = 0
+
+# When IDLE command is running, mailbox is checked once in a while to see if
+# there are any new mails or other changes. This setting defines the minimum
+# time to wait between those checks. Dovecot can also use inotify and
+# kqueue to find out immediately when changes occur.
+#mailbox_idle_check_interval = 30 secs
+
+# Save mails with CR+LF instead of plain LF. This makes sending those mails
+# take less CPU, especially with sendfile() syscall with Linux and FreeBSD.
+# But it also creates a bit more disk I/O which may just make it slower.
+# Also note that if other software reads the mboxes/maildirs, they may handle
+# the extra CRs wrong and cause problems.
+#mail_save_crlf = no
+
+# Max number of mails to keep open and prefetch to memory. This only works with
+# some mailbox formats and/or operating systems.
+#mail_prefetch_count = 0
+
+# How often to scan for stale temporary files and delete them (0 = never).
+# These should exist only after Dovecot dies in the middle of saving mails.
+#mail_temp_scan_interval = 1w
+
+##
+## Maildir-specific settings
+##
+
+# By default LIST command returns all entries in maildir beginning with a dot.
+# Enabling this option makes Dovecot return only entries which are directories.
+# This is done by stat()ing each entry, so it causes more disk I/O.
+# (For systems setting struct dirent->d_type, this check is free and it's
+# done always regardless of this setting)
+#maildir_stat_dirs = no
+
+# When copying a message, do it with hard links whenever possible. This makes
+# the performance much better, and it's unlikely to have any side effects.
+#maildir_copy_with_hardlinks = yes
+
+# Assume Dovecot is the only MUA accessing Maildir: Scan cur/ directory only
+# when its mtime changes unexpectedly or when we can't find the mail otherwise.
+#maildir_very_dirty_syncs = no
+
+# If enabled, Dovecot doesn't use the S=<size> in the Maildir filenames for
+# getting the mail's physical size, except when recalculating Maildir++ quota.
+# This can be useful in systems where a lot of the Maildir filenames have a
+# broken size. The performance hit for enabling this is very small.
+#maildir_broken_filename_sizes = no
+
+# Always move mails from new/ directory to cur/, even when the \Recent flags
+# aren't being reset.
+#maildir_empty_new = no
+
+##
+## mbox-specific settings
+##
+
+# Which locking methods to use for locking mbox. There are four available:
+#  dotlock: Create <mailbox>.lock file. This is the oldest and most NFS-safe
+#           solution. If you want to use /var/mail/ like directory, the users
+#           will need write access to that directory.
+#  dotlock_try: Same as dotlock, but if it fails because of permissions or
+#               because there isn't enough disk space, just skip it.
+#  fcntl  : Use this if possible. Works with NFS too if lockd is used.
+#  flock  : May not exist in all systems. Doesn't work with NFS.
+#  lockf  : May not exist in all systems. Doesn't work with NFS.
+#
+# You can use multiple locking methods; if you do the order they're declared
+# in is important to avoid deadlocks if other MTAs/MUAs are using multiple
+# locking methods as well. Some operating systems don't allow using some of
+# them simultaneously.
+#
+# The Debian value for mbox_write_locks differs from upstream Dovecot. It is
+# changed to be compliant with Debian Policy (section 11.6) for NFS safety.
+#       Dovecot: mbox_write_locks = dotlock fcntl
+#       Debian:  mbox_write_locks = fcntl dotlock
+#
+#mbox_read_locks = fcntl
+#mbox_write_locks = fcntl dotlock
+
+# Maximum time to wait for lock (all of them) before aborting.
+#mbox_lock_timeout = 5 mins
+
+# If dotlock exists but the mailbox isn't modified in any way, override the
+# lock file after this much time.
+#mbox_dotlock_change_timeout = 2 mins
+
+# When mbox changes unexpectedly we have to fully read it to find out what
+# changed. If the mbox is large this can take a long time. Since the change
+# is usually just a newly appended mail, it'd be faster to simply read the
+# new mails. If this setting is enabled, Dovecot does this but still safely
+# fallbacks to re-reading the whole mbox file whenever something in mbox isn't
+# how it's expected to be. The only real downside to this setting is that if
+# some other MUA changes message flags, Dovecot doesn't notice it immediately.
+# Note that a full sync is done with SELECT, EXAMINE, EXPUNGE and CHECK 
+# commands.
+#mbox_dirty_syncs = yes
+
+# Like mbox_dirty_syncs, but don't do full syncs even with SELECT, EXAMINE,
+# EXPUNGE or CHECK commands. If this is set, mbox_dirty_syncs is ignored.
+#mbox_very_dirty_syncs = no
+
+# Delay writing mbox headers until doing a full write sync (EXPUNGE and CHECK
+# commands and when closing the mailbox). This is especially useful for POP3
+# where clients often delete all mails. The downside is that our changes
+# aren't immediately visible to other MUAs.
+#mbox_lazy_writes = yes
+
+# If mbox size is smaller than this (e.g. 100k), don't write index files.
+# If an index file already exists it's still read, just not updated.
+#mbox_min_index_size = 0
+
+# Mail header selection algorithm to use for MD5 POP3 UIDLs when
+# pop3_uidl_format=%m. For backwards compatibility we use apop3d inspired
+# algorithm, but it fails if the first Received: header isn't unique in all
+# mails. An alternative algorithm is "all" that selects all headers.
+#mbox_md5 = apop3d
+
+##
+## mdbox-specific settings
+##
+
+# Maximum dbox file size until it's rotated.
+#mdbox_rotate_size = 2M
+
+# Maximum dbox file age until it's rotated. Typically in days. Day begins
+# from midnight, so 1d = today, 2d = yesterday, etc. 0 = check disabled.
+#mdbox_rotate_interval = 0
+
+# When creating new mdbox files, immediately preallocate their size to
+# mdbox_rotate_size. This setting currently works only in Linux with some
+# filesystems (ext4, xfs).
+#mdbox_preallocate_space = no
+
+##
+## Mail attachments
+##
+
+# sdbox and mdbox support saving mail attachments to external files, which
+# also allows single instance storage for them. Other backends don't support
+# this for now.
+
+# Directory root where to store mail attachments. Disabled, if empty.
+#mail_attachment_dir =
+
+# Attachments smaller than this aren't saved externally. It's also possible to
+# write a plugin to disable saving specific attachments externally.
+#mail_attachment_min_size = 128k
+
+# Filesystem backend to use for saving attachments:
+#  posix : No SiS done by Dovecot (but this might help FS's own deduplication)
+#  sis posix : SiS with immediate byte-by-byte comparison during saving
+#  sis-queue posix : SiS with delayed comparison and deduplication
+#mail_attachment_fs = sis posix
+
+# Hash format to use in attachment filenames. You can add any text and
+# variables: %{md4}, %{md5}, %{sha1}, %{sha256}, %{sha512}, %{size}.
+# Variables can be truncated, e.g. %{sha256:80} returns only first 80 bits
+#mail_attachment_hash = %{sha1}

playbooks/ldh_dovecot/handlers/main.yml

+---
+# handlers file for ldh_dovecot
+- name: restart dovecot
+  service:
+    name: dovecot
+    state: restarted

playbooks/ldh_dovecot/meta/main.yml

+galaxy_info:
+  author: Purism SPC
+  description: Basic Matrix-Synapse for LDH development.
+  company: Purism SPC
+
+  license: AGPL-3.0-or-later
+
+  min_ansible_version: 2.7.1
+
+  galaxy_tags:
+    - imap
+    - pop3
+    - dovecot
+    - mail
+
+dependencies: []
+  # List your role dependencies here, one per line. Be sure to remove the '[]' above,
+  # if you add dependencies to this list.

playbooks/ldh_dovecot/tasks/main.yml

+---
+# tasks file for ldh_dovecot
+- name: Install required Dovecot packages