IMAP: Update role to Debian Buster.

For `ssl_cipher_list` we pick the suggested value from
https://ssl-config.mozilla.org/#server=dovecot&version=2.3.9&config=intermediate&openssl=1.1.1d

At the moment it's equivalent (modulo order) to adding ‘EDH+AESGCM+aRSA’
to ‘EECDH+AESGCM:EECDH+CHACHA20!MEDIUM!LOW!EXP!aNULL!eNULL’.

1 files changed, 26 insertions, 3 deletions

diff --git a/roles/IMAP/files/etc/dovecot/conf.d/20-imap.conf b/roles/IMAP/files/etc/dovecot/conf.d/20-imap.conf
index 3ddedce..de1fbbb 100644
--- a/roles/IMAP/files/etc/dovecot/conf.d/20-imap.conf
+++ b/roles/IMAP/files/etc/dovecot/conf.d/20-imap.conf
@@ -4,82 +4,105 @@
 
 # If nothing happens for this long while client is IDLEing, move the connection
 # to imap-hibernate process and close the old imap process. This saves memory,
 # because connections use very little memory in imap-hibernate process. The
 # downside is that recreating the imap process back uses some resources.
 imap_hibernate_timeout = 15s
 
 # Maximum IMAP command line length. Some clients generate very long command
 # lines with huge mailboxes, so you may need to raise this if you get
 # "Too long argument" or "IMAP command line too large" errors often.
 #imap_max_line_length = 64k
 
 # IMAP logout format string:
 #  %i - total number of bytes read from client
 #  %o - total number of bytes sent to client
 #  %{fetch_hdr_count} - Number of mails with mail header data sent to client
 #  %{fetch_hdr_bytes} - Number of bytes with mail header data sent to client
 #  %{fetch_body_count} - Number of mails with mail body data sent to client
 #  %{fetch_body_bytes} - Number of bytes with mail body data sent to client
 #  %{deleted} - Number of mails where client added \Deleted flag
-#  %{expunged} - Number of mails that client expunged
+#  %{expunged} - Number of mails that client expunged, which does not
+#                include automatically expunged mails
+#  %{autoexpunged} - Number of mails that were automatically expunged after
+#                    client disconnected
 #  %{trashed} - Number of mails that client copied/moved to the
 #               special_use=\Trash mailbox.
-#imap_logout_format = in=%i out=%o
+#  %{appended} - Number of mails saved during the session
+#imap_logout_format = 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}
 
 # Override the IMAP CAPABILITY response. If the value begins with '+',
 # add the given capabilities on top of the defaults (e.g. +XFOO XBAR).
 #imap_capability =
 
 # How long to wait between "OK Still here" notifications when client is
 # IDLEing.
 #imap_idle_notify_interval = 2 mins
 
 # ID field names and values to send to clients. Using * as the value makes
 # Dovecot use the default value. The following fields have default values
 # currently: name, version, os, os-version, support-url, support-email.
 #imap_id_send =
 
 # ID fields sent by client to log. * means everything.
 #imap_id_log =
 
 # Workarounds for various client bugs:
 #   delay-newmail:
 #     Send EXISTS/RECENT new mail notifications only when replying to NOOP
 #     and CHECK commands. Some clients ignore them otherwise, for example OSX
 #     Mail (<v2.1). Outlook Express breaks more badly though, without this it
 #     may show user "Message no longer in server" errors. Note that OE6 still
 #     breaks even with this workaround if synchronization is set to
 #     "Headers Only".
 #   tb-extra-mailbox-sep:
 #     Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
 #     adds extra '/' suffixes to mailbox names. This option causes Dovecot to
 #     ignore the extra '/' instead of treating it as invalid mailbox name.
 #   tb-lsub-flags:
 #     Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g. mbox).
 #     This makes Thunderbird realize they aren't selectable and show them
 #     greyed out, instead of only later giving "not selectable" popup error.
 #
 # The list is space-separated.
 #imap_client_workarounds =
 
 # Host allowed in URLAUTH URLs sent by client. "*" allows all.
 #imap_urlauth_host =
 
+# Enable IMAP LITERAL- extension (replaces LITERAL+)
+#imap_literal_minus = no
+
+# What happens when FETCH fails due to some internal error:
+#   disconnect-immediately:
+#     The FETCH is aborted immediately and the IMAP client is disconnected.
+#   disconnect-after:
+#     The FETCH runs for all the requested mails returning as much data as
+#     possible. The client is finally disconnected without a tagged reply.
+#   no-after:
+#     Same as disconnect-after, but tagged NO reply is sent instead of
+#     disconnecting the client. If the client attempts to FETCH the same failed
+#     mail more than once, the client is disconnected. This is to avoid clients
+#     from going into infinite loops trying to FETCH a broken mail.
+#imap_fetch_failure = disconnect-immediately
+
 protocol imap {
   # Space separated list of plugins to load (default is global mail_plugins).
-  mail_plugins = $mail_plugins imap_stats imap_zlib
+  mail_plugins = $mail_plugins imap_zlib
 
   # Maximum number of IMAP connections allowed for a user from each IP address.
   # NOTE: The username is compared case-sensitively.
   mail_max_userip_connections = 16
 
 #  # TODO Load the 'antispam' plugin for people using the content filter.
 #  # (Otherwise fallback to the static userdb.)
 #  userdb {
 #    driver = ldap
 #    args = /etc/dovecot/dovecot-ldap-userdb.conf.ext
 #
 #    # Default fields can be used to specify defaults that LDAP may override
 #    default_fields = home=/home/mail/virtual/%d/%n
 #  }
 }