Hello, Before I get in to my question is ssl on 993 or starttls on 143 better from a security perspective? I've noticed that I've got a dovecot listener on port 993, below is my doveconf -n output I don't have an imaps listener uncommented should I do so and set it's port to 0? Will that disable the 993 listener? Thanks. Dave. # 2.3.10 (0da0eff44): /usr/local/etc/dovecot/dovecot.conf # Pigeonhole version 0.5.10 (bf8ef1c2) # OS: FreeBSD 12.1-RELEASE-p2 amd64 # Hostname: hostname.example.com auth_cache_size = 10 M auth_default_realm = example.com auth_mechanisms = plain login auth_realms = example.com dict { lastlogin = mysql:/usr/local/etc/dovecot/dovecot-last-login.conf } first_valid_gid = 2100 first_valid_uid = 2100 hostname = hostname.example.com imap_client_workarounds = delay-newhostname tb-extra-hostnamebox-sep tb-lsub-flags imap_idle_notify_interval = 1 mins last_valid_gid = 2100 last_valid_uid = 2100 lda_hostnamebox_autocreate = yes lda_hostnamebox_autosubscribe = yes lda_original_recipient_header = X-Original-To listen = xxx.xxx.xxx.xxx lmtp_rcpt_check_quota = yes log_timestamp = "%Y-%m-%d %H:%M:%S " hostname_access_groups = vhostname hostname_fsync = never hostname_gid = vhostname hostname_home = /var/vhostname/hostnameboxes/%d/%n hostname_location = dbox:~/hostname hostname_plugins = acl fts fts_lucene mail_log notify quota trash virtual welcome zlib mail_crypt hostname_privileged_group = vhostname hostname_server_admin = hostnameto:postmaster at example.com hostname_uid = vhostname managesieve_notify_capability = hostnameto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment hostnamebox date index ihave duplicate mime foreverypart extracttext spamtest spamtestplus virustest editheader imapflags notify imapsieve vnd.dovecot.imapsieve namespace { location = sdbox:/var/vhostname/public/:CONTROL=~/hostname/public:INDEX=~/hostname/public prefix = Public/ separator = / subscriptions = yes type = public } namespace { hidden = no list = yes location = hostnamedir:/var/vhostname/shared/office/.hostnamedir:CONTROL=~/.hostnamedir/control/office:INDEX=~/.hostnamedir/index/office prefix = shared/%%u/ separator = / subscriptions = yes type = shared } namespace inbox { inbox = yes location hostnamebox Drafts { auto = subscribe special_use = \Drafts } hostnamebox Sent { auto = subscribe special_use = \Sent } hostnamebox Spam { auto = subscribe autoexpunge = 30 days special_use = \Junk } hostnamebox Trash { auto = subscribe autoexpunge = 30 days special_use = \Trash } prefix separator = / type = private } passdb { args = /usr/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { acl = vfile:/usr/local/etc/dovecot/global-acls:cache_secs=300 fts = lucene fts_autoindex = yes fts_autoindex_exclude = \Junk fts_autoindex_exclude2 = \Trash fts_autoindex_exclude3 = \Spam fts_autoindex_max_recent_msgs = 80 fts_index_timeout = 90 fts_lucene = whitespace_chars=@. normalize no_snowball imapsieve_hostnamebox1_before file:/var/vhostname/sieve/global/learn-spam.sieve imapsieve_hostnamebox1_causes = COPY imapsieve_hostnamebox1_name = Spam imapsieve_hostnamebox2_before file:/var/vhostname/sieve/global/learn-ham.sieve imapsieve_hostnamebox2_causes = COPY imapsieve_hostnamebox2_from = Spam imapsieve_hostnamebox2_name = * last_login_dict = proxy::lastlogin last_login_key = # hidden, use -P to show it hostname_crypt_curve = prime256v1 hostname_crypt_global_private_key = # hidden, use -P to show it hostname_crypt_global_public_key = # hidden, use -P to show it hostname_crypt_save_version = 2 hostname_log_events = delete undelete expunge copy hostnamebox_delete hostnamebox_rename hostname_log_fields = uid box msgid size quota = count:User quota quota_exceeded_message = Storage quota for this account has been exceeded, please try again later. quota_grace = 10%% quota_rule2 = Trash:ignore quota_status_nouser = DUNNO quota_status_overquota = 552 5.2.2 hostnamebox is full quota_status_success = DUNNO quota_vsizes = true quota_warning = storage=100%% quota-exceeded 100 %u quota_warning2 = storage=95%% quota-warning 95 %u quota_warning3 = storage=90%% quota-warning 90 %u quota_warning4 = storage=85%% quota-warning 85 %u quota_warning5 = storage=75%% quota-warning 75 %u sieve = file:/var/vhostname/sieve/%d/%n/scripts;active=/var/vhostname/sieve/%d/%n/active-script.sieve sieve_before = /var/vhostname/sieve/global/spam-global.sieve sieve_extensions = +notify +imapflags +spamtest +spamtestplus +virustest +editheader sieve_global_extensions = +vnd.dovecot.pipe +vnd.dovecot.execute +vnd.dovecot.environment sieve_max_redirects = 30 sieve_max_script_size = 1M sieve_pipe_bin_dir = /usr/bin sieve_plugins = sieve_imapsieve sieve_extprograms sieve_spamtest_max_header = X-Spamd-Result: default: [[:alnum:]]+ \[-?[[:digit:]]+\.[[:digit:]]+ / (-?[[:digit:]]+\.[[:digit:]]+)\] sieve_spamtest_status_header = X-Spamd-Result: default: [[:alnum:]]+ \[(-?[[:digit:]]+\.[[:digit:]]+) / -?[[:digit:]]+\.[[:digit:]]+\] sieve_spamtest_status_type = score sieve_user_log = /var/vhostname/sieve/sieve_error.log sieve_virustest_status_header = X-Virus-Scan: Found to be (.+)\. sieve_virustest_status_type = text sieve_virustest_text_value1 = clean sieve_virustest_text_value5 = infected trash = /usr/local/etc/dovecot/trash.conf welcome_script = welcome %n postmaster@%d welcome_wait = yes } postmaster_address = postmaster at example.com protocols = imap lmtp sieve sendhostname_path = /usr/local/sbin/sendhostname service auth-worker { user = vhostname } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } unix_listener auth-userdb { group = vhostname mode = 0666 user = vhostname } } service dict { unix_listener dict { mode = 0600 user = vhostname } user = root } service imap-login { inet_listener imap { port = 143 } process_min_avail = 1 } service imap { executable = imap } service lmtp { executable = lmtp unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0660 user = postfix } } service managesieve-login { inet_listener sieve { address = 172.16.21.3 port = 4190 } } service quota-status { client_limit = 1 executable = quota-status -p postfix unix_listener /var/spool/postfix/private/dovecot-quota { group = postfix mode = 0660 user = postfix } } service quota-warning { executable = script /usr/local/etc/dovecot/quota-warning.sh unix_listener quota-warning { group = vhostname mode = 0660 user = vhostname } user = vhostname } service stats { unix_listener stats-reader { group = vhostname mode = 0660 user = vhostname } unix_listener stats-writer { group = vhostname mode = 0660 user = vhostname } } service welcome { executable = script /usr/local/etc/dovecot/welcome.sh unix_listener welcome { user = vhostname } user = vhostname } ssl = required ssl_cert = </usr/local/etc/ssl/acme.sh/example.com/fullchain.crt ssl_cipher_list = EECDH+AESGCM:EDH+AESGCM ssl_curve_list = P-256 ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it ssl_min_protocol = TLSv1.2 ssl_options = no_ticket ssl_prefer_server_ciphers = yes userdb { args = /usr/local/etc/dovecot/dovecot-sql.conf.ext driver = sql } protocol lmtp { hostname_fsync = optimized hostname_plugins = acl fts fts_lucene hostname_log notify quota trash virtual welcome zlib hostname_crypt sieve } protocol lda { hostname_fsync = optimized hostname_plugins = acl fts fts_lucene hostname_log notify quota trash virtual welcome zlib hostname_crypt sieve } protocol imap { hostname_max_userip_connections = 20 hostname_plugins = acl fts fts_lucene hostname_log notify quota trash virtual welcome zlib hostname_crypt imap_acl imap_quota imap_sieve imap_zlib last_login quota welcome } protocol sieve { info_log_path = /var/log/dovecot/dovecot-sieve.log log_path = /var/log/dovecot/dovecot-sieve-errors.log }
Maybe this thread can help you with your first question : https://dovecot.org/pipermail/dovecot/2014-August/097488.html On 13.4.2020. 20:52, David Mehler wrote:> Hello, > > Before I get in to my question is ssl on 993 or starttls on 143 better > from a security perspective? > > I've noticed that I've got a dovecot listener on port 993, below is my > doveconf -n output I don't have an imaps listener uncommented should I > do so and set it's port to 0? Will that disable the 993 listener? > Thanks. > Dave. > > # 2.3.10 (0da0eff44): /usr/local/etc/dovecot/dovecot.conf > # Pigeonhole version 0.5.10 (bf8ef1c2) > # OS: FreeBSD 12.1-RELEASE-p2 amd64 > # Hostname: hostname.example.com > auth_cache_size = 10 M > auth_default_realm = example.com > auth_mechanisms = plain login > auth_realms = example.com > dict { > lastlogin = mysql:/usr/local/etc/dovecot/dovecot-last-login.conf > } > first_valid_gid = 2100 > first_valid_uid = 2100 > hostname = hostname.example.com > imap_client_workarounds = delay-newhostname tb-extra-hostnamebox-sep > tb-lsub-flags > imap_idle_notify_interval = 1 mins > last_valid_gid = 2100 > last_valid_uid = 2100 > lda_hostnamebox_autocreate = yes > lda_hostnamebox_autosubscribe = yes > lda_original_recipient_header = X-Original-To > listen = xxx.xxx.xxx.xxx > lmtp_rcpt_check_quota = yes > log_timestamp = "%Y-%m-%d %H:%M:%S " > hostname_access_groups = vhostname > hostname_fsync = never > hostname_gid = vhostname > hostname_home = /var/vhostname/hostnameboxes/%d/%n > hostname_location = dbox:~/hostname > hostname_plugins = acl fts fts_lucene mail_log notify quota trash > virtual welcome zlib mail_crypt > hostname_privileged_group = vhostname > hostname_server_admin = hostnameto:postmaster at example.com > hostname_uid = vhostname > managesieve_notify_capability = hostnameto > managesieve_sieve_capability = fileinto reject envelope > encoded-character vacation subaddress comparator-i;ascii-numeric > relational regex imap4flags copy include variables body enotify > environment hostnamebox date index ihave duplicate mime foreverypart > extracttext spamtest spamtestplus virustest editheader imapflags > notify imapsieve vnd.dovecot.imapsieve > namespace { > location = sdbox:/var/vhostname/public/:CONTROL=~/hostname/public:INDEX=~/hostname/public > prefix = Public/ > separator = / > subscriptions = yes > type = public > } > namespace { > hidden = no > list = yes > location = hostnamedir:/var/vhostname/shared/office/.hostnamedir:CONTROL=~/.hostnamedir/control/office:INDEX=~/.hostnamedir/index/office > prefix = shared/%%u/ > separator = / > subscriptions = yes > type = shared > } > namespace inbox { > inbox = yes > location > hostnamebox Drafts { > auto = subscribe > special_use = \Drafts > } > hostnamebox Sent { > auto = subscribe > special_use = \Sent > } > hostnamebox Spam { > auto = subscribe > autoexpunge = 30 days > special_use = \Junk > } > hostnamebox Trash { > auto = subscribe > autoexpunge = 30 days > special_use = \Trash > } > prefix > separator = / > type = private > } > passdb { > args = /usr/local/etc/dovecot/dovecot-sql.conf.ext > driver = sql > } > plugin { > acl = vfile:/usr/local/etc/dovecot/global-acls:cache_secs=300 > fts = lucene > fts_autoindex = yes > fts_autoindex_exclude = \Junk > fts_autoindex_exclude2 = \Trash > fts_autoindex_exclude3 = \Spam > fts_autoindex_max_recent_msgs = 80 > fts_index_timeout = 90 > fts_lucene = whitespace_chars=@. normalize no_snowball > imapsieve_hostnamebox1_before > file:/var/vhostname/sieve/global/learn-spam.sieve > imapsieve_hostnamebox1_causes = COPY > imapsieve_hostnamebox1_name = Spam > imapsieve_hostnamebox2_before > file:/var/vhostname/sieve/global/learn-ham.sieve > imapsieve_hostnamebox2_causes = COPY > imapsieve_hostnamebox2_from = Spam > imapsieve_hostnamebox2_name = * > last_login_dict = proxy::lastlogin > last_login_key = # hidden, use -P to show it > hostname_crypt_curve = prime256v1 > hostname_crypt_global_private_key = # hidden, use -P to show it > hostname_crypt_global_public_key = # hidden, use -P to show it > hostname_crypt_save_version = 2 > hostname_log_events = delete undelete expunge copy > hostnamebox_delete hostnamebox_rename > hostname_log_fields = uid box msgid size > quota = count:User quota > quota_exceeded_message = Storage quota for this account has been > exceeded, please try again later. > quota_grace = 10%% > quota_rule2 = Trash:ignore > quota_status_nouser = DUNNO > quota_status_overquota = 552 5.2.2 hostnamebox is full > quota_status_success = DUNNO > quota_vsizes = true > quota_warning = storage=100%% quota-exceeded 100 %u > quota_warning2 = storage=95%% quota-warning 95 %u > quota_warning3 = storage=90%% quota-warning 90 %u > quota_warning4 = storage=85%% quota-warning 85 %u > quota_warning5 = storage=75%% quota-warning 75 %u > sieve = file:/var/vhostname/sieve/%d/%n/scripts;active=/var/vhostname/sieve/%d/%n/active-script.sieve > sieve_before = /var/vhostname/sieve/global/spam-global.sieve > sieve_extensions = +notify +imapflags +spamtest +spamtestplus > +virustest +editheader > sieve_global_extensions = +vnd.dovecot.pipe +vnd.dovecot.execute > +vnd.dovecot.environment > sieve_max_redirects = 30 > sieve_max_script_size = 1M > sieve_pipe_bin_dir = /usr/bin > sieve_plugins = sieve_imapsieve sieve_extprograms > sieve_spamtest_max_header = X-Spamd-Result: default: [[:alnum:]]+ > \[-?[[:digit:]]+\.[[:digit:]]+ / (-?[[:digit:]]+\.[[:digit:]]+)\] > sieve_spamtest_status_header = X-Spamd-Result: default: [[:alnum:]]+ > \[(-?[[:digit:]]+\.[[:digit:]]+) / -?[[:digit:]]+\.[[:digit:]]+\] > sieve_spamtest_status_type = score > sieve_user_log = /var/vhostname/sieve/sieve_error.log > sieve_virustest_status_header = X-Virus-Scan: Found to be (.+)\. > sieve_virustest_status_type = text > sieve_virustest_text_value1 = clean > sieve_virustest_text_value5 = infected > trash = /usr/local/etc/dovecot/trash.conf > welcome_script = welcome %n postmaster@%d > welcome_wait = yes > } > postmaster_address = postmaster at example.com > protocols = imap lmtp sieve > sendhostname_path = /usr/local/sbin/sendhostname > service auth-worker { > user = vhostname > } > service auth { > unix_listener /var/spool/postfix/private/auth { > group = postfix > mode = 0660 > user = postfix > } > unix_listener auth-userdb { > group = vhostname > mode = 0666 > user = vhostname > } > } > service dict { > unix_listener dict { > mode = 0600 > user = vhostname > } > user = root > } > service imap-login { > inet_listener imap { > port = 143 > } > process_min_avail = 1 > } > service imap { > executable = imap > } > service lmtp { > executable = lmtp > unix_listener /var/spool/postfix/private/dovecot-lmtp { > group = postfix > mode = 0660 > user = postfix > } > } > service managesieve-login { > inet_listener sieve { > address = 172.16.21.3 > port = 4190 > } > } > service quota-status { > client_limit = 1 > executable = quota-status -p postfix > unix_listener /var/spool/postfix/private/dovecot-quota { > group = postfix > mode = 0660 > user = postfix > } > } > service quota-warning { > executable = script /usr/local/etc/dovecot/quota-warning.sh > unix_listener quota-warning { > group = vhostname > mode = 0660 > user = vhostname > } > user = vhostname > } > service stats { > unix_listener stats-reader { > group = vhostname > mode = 0660 > user = vhostname > } > unix_listener stats-writer { > group = vhostname > mode = 0660 > user = vhostname > } > } > service welcome { > executable = script /usr/local/etc/dovecot/welcome.sh > unix_listener welcome { > user = vhostname > } > user = vhostname > } > ssl = required > ssl_cert = </usr/local/etc/ssl/acme.sh/example.com/fullchain.crt > ssl_cipher_list = EECDH+AESGCM:EDH+AESGCM > ssl_curve_list = P-256 > ssl_dh = # hidden, use -P to show it > ssl_key = # hidden, use -P to show it > ssl_min_protocol = TLSv1.2 > ssl_options = no_ticket > ssl_prefer_server_ciphers = yes > userdb { > args = /usr/local/etc/dovecot/dovecot-sql.conf.ext > driver = sql > } > protocol lmtp { > hostname_fsync = optimized > hostname_plugins = acl fts fts_lucene hostname_log notify quota > trash virtual welcome zlib hostname_crypt sieve > } > protocol lda { > hostname_fsync = optimized > hostname_plugins = acl fts fts_lucene hostname_log notify quota > trash virtual welcome zlib hostname_crypt sieve > } > protocol imap { > hostname_max_userip_connections = 20 > hostname_plugins = acl fts fts_lucene hostname_log notify quota > trash virtual welcome zlib hostname_crypt imap_acl imap_quota > imap_sieve imap_zlib last_login quota welcome > } > protocol sieve { > info_log_path = /var/log/dovecot/dovecot-sieve.log > log_path = /var/log/dovecot/dovecot-sieve-errors.log > } >
* David Mehler:> Before I get in to my question is ssl on 993 or starttls on 143 better > from a security perspective?On the server side, it makes little difference. STARTTLS just means a number of extra bytes are exchanged while an encrypted connection is being established. If you want to support a wide range of clients, expose both ports. -Ralph
Am 13.04.20 um 20:52 schrieb David Mehler:> Hello, > > Before I get in to my question is ssl on 993 or starttls on 143 better > from a security perspective?implicit TLS is recommended: https://tools.ietf.org/html/rfc8314#section-3 Andreas
On Tue, 14 Apr 2020, Ivo wrote:> Maybe this thread can help you with your first question : > https://dovecot.org/pipermail/dovecot/2014-August/097488.htmlI was more or less going to say the same thing. Further to this, it's more important to make sure your clients enforce SSL/STARTTLS use by disabling auto-discovery, and if you're ultra-conservative, certificate pinning. Joseph Tam <jtam.home at gmail.com>
> Le 14 avr. 2020 ? 18:57, A. Schulze <sca at andreasschulze.de> a ?crit : > > > > Am 13.04.20 um 20:52 schrieb David Mehler: >> Hello, >> >> Before I get in to my question is ssl on 993 or starttls on 143 better >> from a security perspective? > > implicit TLS is recommended: https://tools.ietf.org/html/rfc8314#section-3One rational for this is to make sure broken clients don?t send clear text credential on port 143, even if STARTTLS is required. So from a security perspective, you can consider TLS on port 943 a better solution.