Merge branch 'mail-in-a-box:main' into spamhaus2spamassassin

2024-11-23 02:27:05 +00:00 · 2021-05-16 07:51:12 -07:00 · 2021-05-16 07:51:12 -07:00 · c273c7930e
commit c273c7930e
parent 19a47fc5d4 35fa3fe891
27 changed files with 478 additions and 317 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@ -4,6 +4,38 @@ CHANGELOG
 In Development
 --------------

+Mail:
+
+* Forwarded mail using mail filter rules (in Roundcube; "sieve" rules) stopped re-writing the envelope address at some point, causing forwarded mail to often be marked as spam by the final recipient. These forwards will now re-write the envelope as the Mail-in-a-Box user receiving the mail to comply with SPF/DMARC rules.
+* Sending mail is now possible on port 465 with the "SSL" or "TLS" option in mail clients, and this is now the recommended setting. Port 587 with STARTTLS remains available but should be avoided when configuring new mail clients.
+* Roundcube's login cookie is updated to use a new encryption algorithm (AES-256-CBC instead of DES-EDE-CBC).
+
+DNS:
+
+* The ECDSAP256SHA256 DNSSEC algorithm is now available. If a DS record is set for any of your domain names that have DNS hosted on your box, you will be prompted by status checks to update the DS record at your convenience.
+* Null MX records are added for domains that do not serve mail.
+
+Contacts/calendar:
+
+* Updated Nextcloud to 20.0.8, contacts to 3.5.1, calendar to 2.2.0 (#1960).
+
+Control panel:
+
+* Fixed a crash in the status checks.
+* Small wording improvements.
+
+Setup:
+
+* Minor improvements to the setup scripts.
+
+v0.53a (May 8, 2021)
+--------------------
+
+The download URL for Z-Push has been revised becaue the old URL stopped working.
+
+v0.53 (April 12, 2021)
+----------------------
+
 Software updates:

 * Upgraded Roundcube to version 1.4.11 addressing a security issue, and its desktop notifications plugin.
--- a/README.md
+++ b/README.md
@ -58,7 +58,7 @@ Clone this repository and checkout the tag corresponding to the most recent rele

 	$ git clone https://github.com/mail-in-a-box/mailinabox
 	$ cd mailinabox
-	$ git checkout v0.52
+	$ git checkout v0.53a

 Begin the installation.

--- a/conf/fail2ban/jails.conf
+++ b/conf/fail2ban/jails.conf
@ -38,6 +38,14 @@ logpath  = STORAGE_ROOT/owncloud/nextcloud.log
 maxretry = 20
 findtime = 120

+[miab-postfix465]
+enabled  = true
+port     = 465
+filter   = miab-postfix-submission
+logpath  = /var/log/mail.log
+maxretry = 20
+findtime = 30
+
 [miab-postfix587]
 enabled  = true
 port     = 587
--- a/conf/ios-profile.xml
+++ b/conf/ios-profile.xml
@ -53,7 +53,7 @@
      <key>OutgoingMailServerHostName</key>
      <string>PRIMARY_HOSTNAME</string>
      <key>OutgoingMailServerPortNumber</key>
-      <integer>587</integer>
+      <integer>465</integer>
      <key>OutgoingMailServerUseSSL</key>
      <true/>
      <key>OutgoingPasswordSameAsIncomingPassword</key>
--- a/conf/mozilla-autoconfig.xml
+++ b/conf/mozilla-autoconfig.xml
@ -16,8 +16,8 @@

      <outgoingServer type="smtp">
         <hostname>PRIMARY_HOSTNAME</hostname>
-         <port>587</port>
-         <socketType>STARTTLS</socketType>
+         <port>465</port>
+         <socketType>SSL</socketType>
         <username>%EMAILADDRESS%</username>
         <authentication>password-cleartext</authentication>
         <addThisServer>true</addThisServer>
--- a/conf/zpush/backend_imap.php
+++ b/conf/zpush/backend_imap.php
@ -49,7 +49,7 @@ define('IMAP_FROM_LDAP_FULLNAME', '#givenname #sn');
 define('IMAP_SMTP_METHOD', 'sendmail');

 global $imap_smtp_params;
-$imap_smtp_params = array('host' => 'ssl://127.0.0.1', 'port' => 587, 'auth' => true, 'username' => 'imap_username', 'password' => 'imap_password');
+$imap_smtp_params = array('host' => 'ssl://127.0.0.1', 'port' => 465, 'auth' => true, 'username' => 'imap_username', 'password' => 'imap_password');

 define('MAIL_MIMEPART_CRLF', "\r\n");
 define('IMAP_MEETING_USE_CALDAV', true);
--- a/management/dns_update.py
+++ b/management/dns_update.py
@ -9,7 +9,6 @@ import ipaddress
 import rtyaml
 import dns.resolver

-from mailconfig import get_mail_domains, get_mail_aliases
 from utils import shell, load_env_vars_from_file, safe_domain_name, sort_domains
 from ssl_certificates import get_ssl_certificates, check_certificate

@ -20,10 +19,14 @@ from ssl_certificates import get_ssl_certificates, check_certificate
 DOMAIN_RE = "^(?!\-)(?:[*][.])?(?:[a-zA-Z\d\-_]{0,62}[a-zA-Z\d_]\.){1,126}(?!\d+)[a-zA-Z\d_]{1,63}(\.?)$"

 def get_dns_domains(env):
-	# Add all domain names in use by email users and mail aliases and ensure
-	# PRIMARY_HOSTNAME is in the list.
+	# Add all domain names in use by email users and mail aliases, any
+	# domains we serve web for (except www redirects because that would
+	# lead to infinite recursion here) and ensure PRIMARY_HOSTNAME is in the list.
+	from mailconfig import get_mail_domains
+	from web_update import get_web_domains
 	domains = set()
-	domains |= get_mail_domains(env)
+	domains |= set(get_mail_domains(env))
+	domains |= set(get_web_domains(env, include_www_redirects=False))
 	domains.add(env['PRIMARY_HOSTNAME'])
 	return domains

@ -97,7 +100,8 @@ def do_dns_update(env, force=False):
 	if len(updated_domains) > 0:
 		shell('check_call', ["/usr/sbin/service", "nsd", "restart"])

-	# Write the OpenDKIM configuration tables for all of the domains.
+	# Write the OpenDKIM configuration tables for all of the mail domains.
+	from mailconfig import get_mail_domains
 	if write_opendkim_tables(get_mail_domains(env), env):
 		# Settings changed. Kick opendkim.
 		shell('check_call', ["/usr/sbin/service", "opendkim", "restart"])
@ -122,18 +126,47 @@ def build_zones(env):
 	domains = get_dns_domains(env)
 	zonefiles = get_dns_zones(env)

-	# Custom records to add to zones.
-	additional_records = list(get_custom_dns_config(env))
+	# Create a dictionary of domains to a set of attributes for each
+	# domain, such as whether there are mail users at the domain.
+	from mailconfig import get_mail_domains
 	from web_update import get_web_domains
-	www_redirect_domains = set(get_web_domains(env)) - set(get_web_domains(env, include_www_redirects=False))
+	mail_domains = set(get_mail_domains(env))
+	mail_user_domains = set(get_mail_domains(env, users_only=True)) # i.e. will log in for mail, Nextcloud
+	web_domains = set(get_web_domains(env))
+	auto_domains = web_domains - set(get_web_domains(env, include_auto=False))
+	domains |= auto_domains # www redirects not included in the initial list, see above
+
+	# Add ns1/ns2+PRIMARY_HOSTNAME which must also have A/AAAA records
+	# when the box is acting as authoritative DNS server for its domains.
+	for ns in ("ns1", "ns2"):
+		d = ns + "." + env["PRIMARY_HOSTNAME"]
+		domains.add(d)
+		auto_domains.add(d)
+
+	domains = {
+		domain: {
+			"user": domain in mail_user_domains,
+			"mail": domain in mail_domains,
+			"web": domain in web_domains,
+			"auto": domain in auto_domains,
+		}
+		for domain in domains
+	}
+
+	# For MTA-STS, we'll need to check if the PRIMARY_HOSTNAME certificate is
+	# singned and valid. Check that now rather than repeatedly for each domain.
+	domains[env["PRIMARY_HOSTNAME"]]["certificate-is-valid"] = is_domain_cert_signed_and_valid(env["PRIMARY_HOSTNAME"], env)
+
+	# Load custom records to add to zones.
+	additional_records = list(get_custom_dns_config(env))

 	# Build DNS records for each zone.
 	for domain, zonefile in zonefiles:
 		# Build the records to put in the zone.
-		records = build_zone(domain, domains, additional_records, www_redirect_domains, env)
+		records = build_zone(domain, domains, additional_records, env)
 		yield (domain, zonefile, records)

-def build_zone(domain, all_domains, additional_records, www_redirect_domains, env, is_zone=True):
+def build_zone(domain, domain_properties, additional_records, env, is_zone=True):
 	records = []

 	# For top-level zones, define the authoritative name servers.
@ -145,10 +178,10 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en
 	# 'False' in the tuple indicates these records would not be used if the zone
 	# is managed outside of the box.
 	if is_zone:
-		# Obligatory definition of ns1.PRIMARY_HOSTNAME.
+		# Obligatory NS record to ns1.PRIMARY_HOSTNAME.
 		records.append((None,  "NS",  "ns1.%s." % env["PRIMARY_HOSTNAME"], False))

-		# Define ns2.PRIMARY_HOSTNAME or whatever the user overrides.
+		# NS record to ns2.PRIMARY_HOSTNAME or whatever the user overrides.
 		# User may provide one or more additional nameservers
 		secondary_ns_list = get_secondary_dns(additional_records, mode="NS") \
 			or ["ns2." + env["PRIMARY_HOSTNAME"]]
@ -158,15 +191,6 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en

 	# In PRIMARY_HOSTNAME...
 	if domain == env["PRIMARY_HOSTNAME"]:
-		# Define ns1 and ns2.
-		# 'False' in the tuple indicates these records would not be used if the zone
-		# is managed outside of the box.
-		records.append(("ns1", "A", env["PUBLIC_IP"], False))
-		records.append(("ns2", "A", env["PUBLIC_IP"], False))
-		if env.get('PUBLIC_IPV6'):
-			records.append(("ns1", "AAAA", env["PUBLIC_IPV6"], False))
-			records.append(("ns2", "AAAA", env["PUBLIC_IPV6"], False))
-
 		# Set the A/AAAA records. Do this early for the PRIMARY_HOSTNAME so that the user cannot override them
 		# and we can provide different explanatory text.
 		records.append((None, "A", env["PUBLIC_IP"], "Required. Sets the IP address of the box."))
@ -184,10 +208,11 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en

 	# Add DNS records for any subdomains of this domain. We should not have a zone for
 	# both a domain and one of its subdomains.
-	subdomains = [d for d in all_domains if d.endswith("." + domain)]
+	if is_zone: # don't recurse when we're just loading data for a subdomain
+		subdomains = [d for d in domain_properties if d.endswith("." + domain)]
 		for subdomain in subdomains:
 			subdomain_qname = subdomain[0:-len("." + domain)]
-		subzone = build_zone(subdomain, [], additional_records, www_redirect_domains, env, is_zone=False)
+			subzone = build_zone(subdomain, domain_properties, additional_records, env, is_zone=False)
 			for child_qname, child_rtype, child_value, child_explanation in subzone:
 				if child_qname == None:
 					child_qname = subdomain_qname
@ -220,21 +245,23 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en
 				continue
 		records.append((qname, rtype, value, "(Set by user.)"))

-	# Add defaults if not overridden by the user's custom settings (and not otherwise configured).
+	# Add A/AAAA defaults if not overridden by the user's custom settings (and not otherwise configured).
 	# Any CNAME or A record on the qname overrides A and AAAA. But when we set the default A record,
 	# we should not cause the default AAAA record to be skipped because it thinks a custom A record
 	# was set. So set has_rec_base to a clone of the current set of DNS settings, and don't update
 	# during this process.
 	has_rec_base = list(records)
+	a_expl = "Required. May have a different value. Sets the IP address that %s resolves to for web hosting and other services besides mail. The A record must be present but its value does not affect mail delivery." % domain
+	if domain_properties[domain]["auto"]:
+		if domain.startswith("ns1.") or domain.startswith("ns2."): a_expl = False # omit from 'External DNS' page since this only applies if box is its own DNS server
+		if domain.startswith("www."): a_expl = "Optional. Sets the IP address that %s resolves to so that the box can provide a redirect to the parent domain." % domain
+		if domain.startswith("mta-sts."): a_expl = "Optional. MTA-STS Policy Host serving /.well-known/mta-sts.txt."
+		if domain.startswith("autoconfig."): a_expl = "Provides email configuration autodiscovery support for Thunderbird Autoconfig."
+		if domain.startswith("autodiscover."): a_expl = "Provides email configuration autodiscovery support for Z-Push ActiveSync Autodiscover."
 	defaults = [
-		(None,  "A",    env["PUBLIC_IP"],       "Required. May have a different value. Sets the IP address that %s resolves to for web hosting and other services besides mail. The A record must be present but its value does not affect mail delivery." % domain),
+		(None,  "A",    env["PUBLIC_IP"], a_expl),
 		(None,  "AAAA", env.get('PUBLIC_IPV6'), "Optional. Sets the IPv6 address that %s resolves to, e.g. for web hosting. (It is not necessary for receiving mail on this domain.)" % domain),
 	]
-	if "www." + domain in www_redirect_domains:
-		defaults += [
-			("www", "A",    env["PUBLIC_IP"],       "Optional. Sets the IP address that www.%s resolves to so that the box can provide a redirect to the parent domain." % domain),
-			("www", "AAAA", env.get('PUBLIC_IPV6'), "Optional. Sets the IPv6 address that www.%s resolves to so that the box can provide a redirect to the parent domain." % domain),
-		]
 	for qname, rtype, value, explanation in defaults:
 		if value is None or value.strip() == "": continue # skip IPV6 if not set
 		if not is_zone and qname == "www": continue # don't create any default 'www' subdomains on what are themselves subdomains
@ -248,6 +275,7 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en
 	# Don't pin the list of records that has_rec checks against anymore.
 	has_rec_base = records

+	if domain_properties[domain]["mail"]:
 		# The MX record says where email for the domain should be delivered: Here!
 		if not has_rec(None, "MX", prefix="10 "):
 			records.append((None,  "MX",  "10 %s." % env["PRIMARY_HOSTNAME"], "Required. Specifies the hostname (and priority) of the machine that handles @%s mail." % domain))
@ -272,40 +300,16 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en
 		if not has_rec("_dmarc", "TXT", prefix="v=DMARC1; "):
 			records.append(("_dmarc", "TXT", 'v=DMARC1; p=quarantine', "Recommended. Specifies that mail that does not originate from the box but claims to be from @%s or which does not have a valid DKIM signature is suspect and should be quarantined by the recipient's mail system." % domain))

-	# For any subdomain with an A record but no SPF or DMARC record, add strict policy records.
-	all_resolvable_qnames = set(r[0] for r in records if r[1] in ("A", "AAAA"))
-	for qname in all_resolvable_qnames:
-		if not has_rec(qname, "TXT", prefix="v=spf1 "):
-			records.append((qname,  "TXT", 'v=spf1 -all', "Recommended. Prevents use of this domain name for outbound mail by specifying that no servers are valid sources for mail from @%s. If you do send email from this domain name you should either override this record such that the SPF rule does allow the originating server, or, take the recommended approach and have the box handle mail for this domain (simply add any receiving alias at this domain name to make this machine treat the domain name as one of its mail domains)." % (qname + "." + domain)))
-		dmarc_qname = "_dmarc" + ("" if qname is None else "." + qname)
-		if not has_rec(dmarc_qname, "TXT", prefix="v=DMARC1; "):
-			records.append((dmarc_qname, "TXT", 'v=DMARC1; p=reject', "Recommended. Prevents use of this domain name for outbound mail by specifying that the SPF rule should be honoured for mail from @%s." % (qname + "." + domain)))
-
+	if domain_properties[domain]["user"]:
 		# Add CardDAV/CalDAV SRV records on the non-primary hostname that points to the primary hostname
 		# for autoconfiguration of mail clients (so only domains hosting user accounts need it).
 		# The SRV record format is priority (0, whatever), weight (0, whatever), port, service provider hostname (w/ trailing dot).
-	if domain != env["PRIMARY_HOSTNAME"] and domain in get_mail_domains(env, users_only=True):
+		if domain != env["PRIMARY_HOSTNAME"]:
 			for dav in ("card", "cal"):
 				qname = "_" + dav + "davs._tcp"
 				if not has_rec(qname, "SRV"):
 					records.append((qname, "SRV", "0 0 443 " + env["PRIMARY_HOSTNAME"] + ".", "Recommended. Specifies the hostname of the server that handles CardDAV/CalDAV services for email addresses on this domain."))

-	# Adds autoconfiguration A records for all domains that there are user accounts at.
-	# This allows the following clients to automatically configure email addresses in the respective applications.
-	# autodiscover.* - Z-Push ActiveSync Autodiscover
-	# autoconfig.* - Thunderbird Autoconfig
-	if domain in get_mail_domains(env, users_only=True):
-		autodiscover_records = [
-			("autodiscover", "A", env["PUBLIC_IP"], "Provides email configuration autodiscovery support for Z-Push ActiveSync Autodiscover."),
-			("autodiscover", "AAAA", env["PUBLIC_IPV6"], "Provides email configuration autodiscovery support for Z-Push ActiveSync Autodiscover."),
-			("autoconfig", "A", env["PUBLIC_IP"], "Provides email configuration autodiscovery support for Thunderbird Autoconfig."),
-			("autoconfig", "AAAA", env["PUBLIC_IPV6"], "Provides email configuration autodiscovery support for Thunderbird Autoconfig.")
-		]
-		for qname, rtype, value, explanation in autodiscover_records:
-			if value is None or value.strip() == "": continue # skip IPV6 if not set
-			if not has_rec(qname, rtype):
-				records.append((qname, rtype, value, explanation))
-
 	# If this is a domain name that there are email addresses configured for, i.e. "something@"
 	# this domain name, then the domain name is a MTA-STS (https://tools.ietf.org/html/rfc8461)
 	# Policy Domain.
@ -321,25 +325,12 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en
 	# subdomain must be valid certificate for that domain. Do not set an MTA-STS policy if either
 	# certificate in use is not valid (e.g. because it is self-signed and a valid certificate has not
 	# yet been provisioned). Since we cannot provision a certificate without A/AAAA records, we
-	# always set them --- only the TXT records depend on there being valid certificates.
-	mta_sts_enabled = False
-	mta_sts_records = [
-		("mta-sts", "A", env["PUBLIC_IP"], "Optional. MTA-STS Policy Host serving /.well-known/mta-sts.txt."),
-		("mta-sts", "AAAA", env.get('PUBLIC_IPV6'), "Optional. MTA-STS Policy Host serving /.well-known/mta-sts.txt."),
-	]
-	if domain in get_mail_domains(env):
-		# Check that PRIMARY_HOSTNAME and the mta_sts domain both have valid certificates.
-		for d in (env['PRIMARY_HOSTNAME'], "mta-sts." + domain):
-			cert = get_ssl_certificates(env).get(d)
-			if not cert:
-				break # no certificate provisioned for this domain
-			cert_status = check_certificate(d, cert['certificate'], cert['private-key'])
-			if cert_status[0] != 'OK':
-				break # certificate is not valid
-		else:
-			# 'break' was not encountered above, so both domains are good
-			mta_sts_enabled = True
-	if mta_sts_enabled:
+	# always set them (by including them in the www domains) --- only the TXT records depend on there
+	# being valid certificates.
+	mta_sts_records = [ ]
+	if domain_properties[domain]["mail"] \
+	  and domain_properties[env["PRIMARY_HOSTNAME"]]["certificate-is-valid"] \
+	  and is_domain_cert_signed_and_valid("mta-sts." + domain, env):
 		# Compute an up-to-32-character hash of the policy file. We'll take a SHA-1 hash of the policy
 		# file (20 bytes) and encode it as base-64 (28 bytes, using alphanumeric alternate characters
 		# instead of '+' and '/' which are not allowed in an MTA-STS policy id) but then just take its
@ -356,15 +347,39 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en
 		if env.get("MTA_STS_TLSRPT_RUA") and not has_rec("_smtp._tls", "TXT", prefix="v=TLSRPTv1;"):
 			mta_sts_records.append(("_smtp._tls", "TXT", "v=TLSRPTv1; rua=" + env["MTA_STS_TLSRPT_RUA"], "Optional. Enables MTA-STS reporting."))
 	for qname, rtype, value, explanation in mta_sts_records:
-		if value is None or value.strip() == "": continue # skip IPV6 if not set
 		if not has_rec(qname, rtype):
 			records.append((qname, rtype, value, explanation))

+	# Add no-mail-here records for any qname that has an A or AAAA record
+	# but no MX record. This would include domain itself if domain is a
+	# non-mail domain and also may include qnames from custom DNS records.
+	# Do this once at the end of generating a zone.
+	if is_zone:
+		qnames_with_a = set(qname for (qname, rtype, value, explanation) in records if rtype in ("A", "AAAA"))
+		qnames_with_mx = set(qname for (qname, rtype, value, explanation) in records if rtype == "MX")
+		for qname in qnames_with_a - qnames_with_mx:
+			# Mark this domain as not sending mail with hard-fail SPF and DMARC records.
+			d = (qname+"." if qname else "") + domain
+			if not has_rec(qname, "TXT", prefix="v=spf1 "):
+				records.append((qname,  "TXT", 'v=spf1 -all', "Recommended. Prevents use of this domain name for outbound mail by specifying that no servers are valid sources for mail from @%s. If you do send email from this domain name you should either override this record such that the SPF rule does allow the originating server, or, take the recommended approach and have the box handle mail for this domain (simply add any receiving alias at this domain name to make this machine treat the domain name as one of its mail domains)." % d))
+			if not has_rec("_dmarc" + ("."+qname if qname else ""), "TXT", prefix="v=DMARC1; "):
+				records.append(("_dmarc" + ("."+qname if qname else ""), "TXT", 'v=DMARC1; p=reject', "Recommended. Prevents use of this domain name for outbound mail by specifying that the SPF rule should be honoured for mail from @%s." % d))
+
+			# And with a null MX record (https://explained-from-first-principles.com/email/#null-mx-record)
+			if not has_rec(qname, "MX"):
+				records.append((qname, "MX", '0 .', "Recommended. Prevents use of this domain name for incoming mail."))
+
 	# Sort the records. The None records *must* go first in the nsd zone file. Otherwise it doesn't matter.
 	records.sort(key = lambda rec : list(reversed(rec[0].split(".")) if rec[0] is not None else ""))

 	return records

+def is_domain_cert_signed_and_valid(domain, env):
+	cert = get_ssl_certificates(env).get(domain)
+	if not cert: return False # no certificate provisioned
+	cert_status = check_certificate(domain, cert['certificate'], cert['private-key'])
+	return cert_status[0] == 'OK'
+
 ########################################################################

 def build_tlsa_record(env):
@ -429,6 +444,7 @@ def build_sshfp_records():
 	# to the zone file (that trigger bumping the serial number). However,
 	# if SSH has been configured to listen on a nonstandard port, we must
 	# specify that port to sshkeyscan.
+
 	port = 22
 	with open('/etc/ssh/sshd_config', 'r') as f:
 		for line in f:
@ -439,8 +455,11 @@ def build_sshfp_records():
 				except ValueError:
 					pass
 				break
+
 	keys = shell("check_output", ["ssh-keyscan", "-t", "rsa,dsa,ecdsa,ed25519", "-p", str(port), "localhost"])
-	for key in sorted(keys.split("\n")):
+	keys = sorted(keys.split("\n"))
+
+	for key in keys:
 		if key.strip() == "" or key[0] == "#": continue
 		try:
 			host, keytype, pubkey = key.split(" ")
@ -460,13 +479,16 @@ def write_nsd_zone(domain, zonefile, records, env, force):
 	# On the $ORIGIN line, there's typically a ';' comment at the end explaining
 	# what the $ORIGIN line does. Any further data after the domain confuses
 	# ldns-signzone, however. It used to say '; default zone domain'.
-
+	#
 	# The SOA contact address for all of the domains on this system is hostmaster
 	# @ the PRIMARY_HOSTNAME. Hopefully that's legit.
-
+	#
 	# For the refresh through TTL fields, a good reference is:
 	# http://www.peerwisdom.org/2013/05/15/dns-understanding-the-soa-record/
-
+	#
+	# A hash of the available DNSSEC keys are added in a comment so that when
+	# the keys change we force a re-generation of the zone which triggers
+	# re-signing it.

 	zone = """
 $ORIGIN {domain}.
@ -502,6 +524,9 @@ $TTL 86400          ; default time to live
 			value = v2
 		zone += value + "\n"

+	# Append a stable hash of DNSSEC signing keys in a comment.
+	zone += "\n; DNSSEC signing keys hash: {}\n".format(hash_dnssec_keys(domain, env))
+
 	# DNSSEC requires re-signing a zone periodically. That requires
 	# bumping the serial number even if no other records have changed.
 	# We don't see the DNSSEC records yet, so we have to figure out
@ -612,53 +637,77 @@ zone:

 ########################################################################

-def dnssec_choose_algo(domain, env):
-	if '.' in domain and domain.rsplit('.')[-1] in \
-		("email", "guide", "fund", "be", "lv"):
-		# At GoDaddy, RSASHA256 is the only algorithm supported
-		# for .email and .guide.
-		# A variety of algorithms are supported for .fund. This
-		# is preferred.
-		# Gandi tells me that .be does not support RSASHA1-NSEC3-SHA1
-        # Nic.lv does not support RSASHA1-NSEC3-SHA1 for .lv tld's
-		return "RSASHA256"
+def find_dnssec_signing_keys(domain, env):
+	# For key that we generated (one per algorithm)...
+	d = os.path.join(env['STORAGE_ROOT'], 'dns/dnssec')
+	keyconfs = [f for f in os.listdir(d) if f.endswith(".conf")]
+	for keyconf in keyconfs:
+		# Load the file holding the KSK and ZSK key filenames.
+		keyconf_fn = os.path.join(d, keyconf)
+		keyinfo = load_env_vars_from_file(keyconf_fn)

-	# For any domain we were able to sign before, don't change the algorithm
-	# on existing users. We'll probably want to migrate to SHA256 later.
-	return "RSASHA1-NSEC3-SHA1"
+		# Skip this key if the conf file has a setting named DOMAINS,
+		# holding a comma-separated list of domain names, and if this
+		# domain is not in the list. This allows easily disabling a
+		# key by setting "DOMAINS=" or "DOMAINS=none", other than
+		# deleting the key's .conf file, which might result in the key
+		# being regenerated next upgrade. Keys should be disabled if
+		# they are not needed to reduce the DNSSEC query response size.
+		if "DOMAINS" in keyinfo and domain not in [dd.strip() for dd in keyinfo["DOMAINS"].split(",")]:
+			continue
+
+		for keytype in ("KSK", "ZSK"):
+			yield keytype, keyinfo[keytype]
+
+def hash_dnssec_keys(domain, env):
+	# Create a stable (by sorting the items) hash of all of the private keys
+	# that will be used to sign this domain.
+	keydata = []
+	for keytype, keyfn in sorted(find_dnssec_signing_keys(domain, env)):
+		oldkeyfn = os.path.join(env['STORAGE_ROOT'], 'dns/dnssec', keyfn + ".private")
+		keydata.append(keytype)
+		keydata.append(keyfn)
+		with open(oldkeyfn, "r") as fr:
+			keydata.append( fr.read() )
+	keydata = "".join(keydata).encode("utf8")
+	return hashlib.sha1(keydata).hexdigest()

 def sign_zone(domain, zonefile, env):
-	algo = dnssec_choose_algo(domain, env)
-	dnssec_keys = load_env_vars_from_file(os.path.join(env['STORAGE_ROOT'], 'dns/dnssec/%s.conf' % algo))
+	# Sign the zone with all of the keys that were generated during
+	# setup so that the user can choose which to use in their DS record at
+	# their registrar, and also to support migration to newer algorithms.

-	# In order to use the same keys for all domains, we have to generate
-	# a new .key file with a DNSSEC record for the specific domain. We
-	# can reuse the same key, but it won't validate without a DNSSEC
-	# record specifically for the domain.
+	# In order to use the key files generated at setup which are for
+	# the domain _domain_, we have to re-write the files and place
+	# the actual domain name in it, so that ldns-signzone works.
 	#
+	# Patch each key, storing the patched version in /tmp for now.
+	# Each key has a .key and .private file. Collect a list of filenames
+	# for all of the keys (and separately just the key-signing keys).
+	all_keys = []
+	ksk_keys = []
+	for keytype, keyfn in find_dnssec_signing_keys(domain, env):
+		newkeyfn = '/tmp/' + keyfn.replace("_domain_", domain)
+
+		for ext in (".private", ".key"):
 			# Copy the .key and .private files to /tmp to patch them up.
 			#
 			# Use os.umask and open().write() to securely create a copy that only
 			# we (root) can read.
-	files_to_kill = []
-	for key in ("KSK", "ZSK"):
-		if dnssec_keys.get(key, "").strip() == "": raise Exception("DNSSEC is not properly set up.")
-		oldkeyfn = os.path.join(env['STORAGE_ROOT'], 'dns/dnssec/' + dnssec_keys[key])
-		newkeyfn = '/tmp/' + dnssec_keys[key].replace("_domain_", domain)
-		dnssec_keys[key] = newkeyfn
-		for ext in (".private", ".key"):
-			if not os.path.exists(oldkeyfn + ext): raise Exception("DNSSEC is not properly set up.")
-			with open(oldkeyfn + ext, "r") as fr:
+			oldkeyfn = os.path.join(env['STORAGE_ROOT'], 'dns/dnssec', keyfn + ext)
+			with open(oldkeyfn, "r") as fr:
 				keydata = fr.read()
-			keydata = keydata.replace("_domain_", domain) # trick ldns-signkey into letting our generic key be used by this zone
-			fn = newkeyfn + ext
+			keydata = keydata.replace("_domain_", domain)
 			prev_umask = os.umask(0o77) # ensure written file is not world-readable
 			try:
-				with open(fn, "w") as fw:
+				with open(newkeyfn + ext, "w") as fw:
 					fw.write(keydata)
 			finally:
 				os.umask(prev_umask) # other files we write should be world-readable
-			files_to_kill.append(fn)
+
+		# Put the patched key filename base (without extension) into the list of keys we'll sign with.
+		all_keys.append(newkeyfn)
+		if keytype == "KSK": ksk_keys.append(newkeyfn)

 	# Do the signing.
 	expiry_date = (datetime.datetime.now() + datetime.timedelta(days=30)).strftime("%Y%m%d")
@ -671,32 +720,34 @@ def sign_zone(domain, zonefile, env):

 		# zonefile to sign
 		"/etc/nsd/zones/" + zonefile,
-
+	]
 		# keys to sign with (order doesn't matter -- it'll figure it out)
-		dnssec_keys["KSK"],
-		dnssec_keys["ZSK"],
-	])
+		+ all_keys
+	)

 	# Create a DS record based on the patched-up key files. The DS record is specific to the
 	# zone being signed, so we can't use the .ds files generated when we created the keys.
 	# The DS record points to the KSK only. Write this next to the zone file so we can
 	# get it later to give to the user with instructions on what to do with it.
 	#
-	# We want to be able to validate DS records too, but multiple forms may be valid depending
-	# on the digest type. So we'll write all (both) valid records. Only one DS record should
-	# actually be deployed. Preferebly the first.
+	# Generate a DS record for each key. There are also several possible hash algorithms that may
+	# be used, so we'll pre-generate all for each key. One DS record per line. Only one
+	# needs to actually be deployed at the registrar. We'll select the preferred one
+	# in the status checks.
 	with open("/etc/nsd/zones/" + zonefile + ".ds", "w") as f:
-		for digest_type in ('2', '1'):
+		for key in ksk_keys:
+			for digest_type in ('1', '2', '4'):
 				rr_ds = shell('check_output', ["/usr/bin/ldns-key2ds",
 					"-n", # output to stdout
-				"-" + digest_type, # 1=SHA1, 2=SHA256
-				dnssec_keys["KSK"] + ".key"
+					"-" + digest_type, # 1=SHA1, 2=SHA256, 4=SHA384
+					key + ".key"
 				])
 				f.write(rr_ds)

-	# Remove our temporary file.
-	for fn in files_to_kill:
-		os.unlink(fn)
+	# Remove the temporary patched key files.
+	for fn in all_keys:
+		os.unlink(fn + ".private")
+		os.unlink(fn + ".key")

 ########################################################################

--- a/management/status_checks.py
+++ b/management/status_checks.py
@ -34,6 +34,7 @@ def get_services():
 		{ "name": "SSH Login (ssh)", "port": get_ssh_port(), "public": True, },
 		{ "name": "Public DNS (nsd4)", "port": 53, "public": True, },
 		{ "name": "Incoming Mail (SMTP/postfix)", "port": 25, "public": True, },
+		{ "name": "Outgoing Mail (SMTP 465/postfix)", "port": 465, "public": True, },
 		{ "name": "Outgoing Mail (SMTP 587/postfix)", "port": 587, "public": True, },
 		#{ "name": "Postfix/master", "port": 10587, "public": True, },
 		{ "name": "IMAPS (dovecot)", "port": 993, "public": True, },
@ -42,7 +43,7 @@ def get_services():
 		{ "name": "HTTPS Web (nginx)", "port": 443, "public": True, },
 	]

-def run_checks(rounded_values, env, output, pool):
+def run_checks(rounded_values, env, output, pool, domains_to_check=None):
 	# run systems checks
 	output.add_heading("System")

@ -63,7 +64,7 @@ def run_checks(rounded_values, env, output, pool):
 	# perform other checks asynchronously

 	run_network_checks(env, output)
-	run_domain_checks(rounded_values, env, output, pool)
+	run_domain_checks(rounded_values, env, output, pool, domains_to_check=domains_to_check)

 def get_ssh_port():
 	# Returns ssh port
@ -300,7 +301,7 @@ def run_network_checks(env, output):
 			which may prevent recipients from receiving your email. See http://www.spamhaus.org/query/ip/%s."""
 			% (env['PUBLIC_IP'], zen, env['PUBLIC_IP']))

-def run_domain_checks(rounded_time, env, output, pool):
+def run_domain_checks(rounded_time, env, output, pool, domains_to_check=None):
 	# Get the list of domains we handle mail for.
 	mail_domains = get_mail_domains(env)

@ -311,6 +312,7 @@ def run_domain_checks(rounded_time, env, output, pool):
 	# Get the list of domains we serve HTTPS for.
 	web_domains = set(get_web_domains(env))

+	if domains_to_check is None:
 		domains_to_check = mail_domains | dns_domains | web_domains

 	# Remove "www", "autoconfig", "autodiscover", and "mta-sts" subdomains, which we group with their parent,
@ -557,61 +559,103 @@ def check_dns_zone_suggestions(domain, env, output, dns_zonefiles, domains_with_


 def check_dnssec(domain, env, output, dns_zonefiles, is_checking_primary=False):
-	# See if the domain has a DS record set at the registrar. The DS record may have
-	# several forms. We have to be prepared to check for any valid record. We've
-	# pre-generated all of the valid digests --- read them in.
+	# See if the domain has a DS record set at the registrar. The DS record must
+	# match one of the keys that we've used to sign the zone. It may use one of
+	# several hashing algorithms. We've pre-generated all possible valid DS
+	# records, although some will be preferred.
+
+	alg_name_map = { '7': 'RSASHA1-NSEC3-SHA1', '8': 'RSASHA256', '13': 'ECDSAP256SHA256' }
+	digalg_name_map = { '1': 'SHA-1', '2': 'SHA-256', '4': 'SHA-384' }
+
+	# Read in the pre-generated DS records
+	expected_ds_records = { }
 	ds_file = '/etc/nsd/zones/' + dns_zonefiles[domain] + '.ds'
 	if not os.path.exists(ds_file): return # Domain is in our database but DNS has not yet been updated.
-	ds_correct = open(ds_file).read().strip().split("\n")
-	digests = { }
-	for rr_ds in ds_correct:
+	with open(ds_file) as f:
+		for rr_ds in f:
+			rr_ds = rr_ds.rstrip()
 			ds_keytag, ds_alg, ds_digalg, ds_digest = rr_ds.split("\t")[4].split(" ")
-		digests[ds_digalg] = ds_digest

 			# Some registrars may want the public key so they can compute the digest. The DS
 			# record that we suggest using is for the KSK (and that's how the DS records were generated).
-	alg_name_map = { '7': 'RSASHA1-NSEC3-SHA1', '8': 'RSASHA256' }
+			# We'll also give the nice name for the key algorithm.
 			dnssec_keys = load_env_vars_from_file(os.path.join(env['STORAGE_ROOT'], 'dns/dnssec/%s.conf' % alg_name_map[ds_alg]))
 			dnsssec_pubkey = open(os.path.join(env['STORAGE_ROOT'], 'dns/dnssec/' + dnssec_keys['KSK'] + '.key')).read().split("\t")[3].split(" ")[3]

+			expected_ds_records[ (ds_keytag, ds_alg, ds_digalg, ds_digest) ] = {
+				"record": rr_ds,
+				"keytag": ds_keytag,
+				"alg": ds_alg,
+				"alg_name": alg_name_map[ds_alg],
+				"digalg": ds_digalg,
+				"digalg_name": digalg_name_map[ds_digalg],
+				"digest": ds_digest,
+				"pubkey": dnsssec_pubkey,
+			}
+
 	# Query public DNS for the DS record at the registrar.
-	ds = query_dns(domain, "DS", nxdomain=None)
-	ds_looks_valid = ds and len(ds.split(" ")) == 4
-	if ds_looks_valid: ds = ds.split(" ")
-	if ds_looks_valid and ds[0] == ds_keytag and ds[1] == ds_alg and ds[3] == digests.get(ds[2]):
-		if is_checking_primary: return
-		output.print_ok("DNSSEC 'DS' record is set correctly at registrar.")
+	ds = query_dns(domain, "DS", nxdomain=None, as_list=True)
+	if ds is None or isinstance(ds, str): ds = []
+
+	# There may be more that one record, so we get the result as a list.
+	# Filter out records that don't look valid, just in case, and split
+	# each record on spaces.
+	ds = [tuple(str(rr).split(" ")) for rr in ds if len(str(rr).split(" ")) == 4]
+
+	if len(ds) == 0:
+		output.print_warning("""This domain's DNSSEC DS record is not set. The DS record is optional. The DS record activates DNSSEC. See below for instructions.""")
 	else:
-		if ds == None:
-			if is_checking_primary: return
-			output.print_warning("""This domain's DNSSEC DS record is not set. The DS record is optional. The DS record activates DNSSEC.
-				To set a DS record, you must follow the instructions provided by your domain name registrar and provide to them this information:""")
+		matched_ds = set(ds) & set(expected_ds_records)
+		if matched_ds:
+			# At least one DS record matches one that corresponds with one of the ways we signed
+			# the zone, so it is valid.
+			#
+			# But it may not be preferred. Only algorithm 13 is preferred. Warn if any of the
+			# matched zones uses a different algorithm.
+			if set(r[1] for r in matched_ds) == { '13' }: # all are alg 13
+				output.print_ok("DNSSEC 'DS' record is set correctly at registrar.")
+				return
+			elif '13' in set(r[1] for r in matched_ds): # some but not all are alg 13
+				output.print_ok("DNSSEC 'DS' record is set correctly at registrar. (Records using algorithm other than ECDSAP256SHA256 should be removed.)")
+				return
+			else: # no record uses alg 13
+				output.print_warning("DNSSEC 'DS' record set at registrar is valid but should be updated to ECDSAP256SHA256 (see below).")
 		else:
 			if is_checking_primary:
 				output.print_error("""The DNSSEC 'DS' record for %s is incorrect. See further details below.""" % domain)
 				return
 			output.print_error("""This domain's DNSSEC DS record is incorrect. The chain of trust is broken between the public DNS system
 				and this machine's DNS server. It may take several hours for public DNS to update after a change. If you did not recently
-				make a change, you must resolve this immediately by following the instructions provided by your domain name registrar and
-				provide to them this information:""")
+				make a change, you must resolve this immediately (see below).""")
+
+	output.print_line("""Follow the instructions provided by your domain name registrar to set a DS record.
+		Registrars support different sorts of DS records. Use the first option that works:""")
+	preferred_ds_order = [(7, 1), (7, 2), (8, 4), (13, 4), (8, 1), (8, 2), (13, 1), (13, 2)] # low to high
+	def preferred_ds_order_func(ds_suggestion):
+		k = (int(ds_suggestion['alg']), int(ds_suggestion['digalg']))
+		if k in preferred_ds_order:
+			return preferred_ds_order.index(k)
+		return -1 # index before first item
 	output.print_line("")
-		output.print_line("Key Tag: " + ds_keytag + ("" if not ds_looks_valid or ds[0] == ds_keytag else " (Got '%s')" % ds[0]))
+	for i, ds_suggestion in enumerate(sorted(expected_ds_records.values(), key=preferred_ds_order_func, reverse=True)):
+		output.print_line("")
+		output.print_line("Option " + str(i+1) + ":")
+		output.print_line("----------")
+		output.print_line("Key Tag: " + ds_suggestion['keytag'])
 		output.print_line("Key Flags: KSK")
-		output.print_line(
-			  ("Algorithm: %s / %s" % (ds_alg, alg_name_map[ds_alg]))
-			+ ("" if not ds_looks_valid or ds[1] == ds_alg else " (Got '%s')" % ds[1]))
-			# see http://www.iana.org/assignments/dns-sec-alg-numbers/dns-sec-alg-numbers.xhtml
-		output.print_line("Digest Type: 2 / SHA-256")
-			# http://www.ietf.org/assignments/ds-rr-types/ds-rr-types.xml
-		output.print_line("Digest: " + digests['2'])
-		if ds_looks_valid and ds[3] != digests.get(ds[2]):
-			output.print_line("(Got digest type %s and digest %s which do not match.)" % (ds[2], ds[3]))
+		output.print_line("Algorithm: %s / %s" % (ds_suggestion['alg'], ds_suggestion['alg_name']))
+		output.print_line("Digest Type: %s / %s" % (ds_suggestion['digalg'], ds_suggestion['digalg_name']))
+		output.print_line("Digest: " + ds_suggestion['digest'])
 		output.print_line("Public Key: ")
-		output.print_line(dnsssec_pubkey, monospace=True)
+		output.print_line(ds_suggestion['pubkey'], monospace=True)
 		output.print_line("")
 		output.print_line("Bulk/Record Format:")
-		output.print_line("" + ds_correct[0])
+		output.print_line(ds_suggestion['record'], monospace=True)
+	if len(ds) > 0:
 		output.print_line("")
+		output.print_line("The DS record is currently set to:")
+		for rr in ds:
+			output.print_line("Key Tag: {0}, Algorithm: {1}, Digest Type: {2}, Digest: {3}".format(*rr))

 def check_mail_domain(domain, env, output):
 	# Check the MX record.
@ -621,6 +665,8 @@ def check_mail_domain(domain, env, output):

 	if mx is None:
 		mxhost = None
+	elif mx == "[timeout]":
+		mxhost = None
 	else:
 		# query_dns returns a semicolon-delimited list
 		# of priority-host pairs.
@ -713,7 +759,7 @@ def check_web_domain(domain, rounded_time, ssl_certificates, env, output):
 	# website for also needs a signed certificate.
 	check_ssl_cert(domain, rounded_time, ssl_certificates, env, output)

-def query_dns(qname, rtype, nxdomain='[Not Set]', at=None):
+def query_dns(qname, rtype, nxdomain='[Not Set]', at=None, as_list=False):
 	# Make the qname absolute by appending a period. Without this, dns.resolver.query
 	# will fall back a failed lookup to a second query with this machine's hostname
 	# appended. This has been causing some false-positive Spamhaus reports. The
@ -750,6 +796,9 @@ def query_dns(qname, rtype, nxdomain='[Not Set]', at=None):
 	if rtype in ("A", "AAAA"):
 		response = [normalize_ip(str(r)) for r in response]

+	if as_list:
+		return response
+
 	# There may be multiple answers; concatenate the response. Remove trailing
 	# periods from responses since that's how qnames are encoded in DNS but is
 	# confusing for us. The order of the answers doesn't matter, so sort so we
@ -1050,3 +1099,7 @@ if __name__ == "__main__":

 	elif sys.argv[1] == "--version":
 		print(what_version_is_this(env))
+
+	elif sys.argv[1] == "--only":
+		with multiprocessing.pool.Pool(processes=10) as pool:
+			run_checks(False, env, ConsoleOutput(), pool, domains_to_check=sys.argv[2:])
--- a/management/templates/mail-guide.html
+++ b/management/templates/mail-guide.html
@ -30,8 +30,8 @@
 					<tr><th>Mail server</th> <td>{{hostname}}</td>
 					<tr><th>IMAP Port</th> <td>993</td></tr>
 					<tr><th>IMAP Security</th> <td>SSL or TLS</td></tr>
-					<tr><th>SMTP Port</th> <td>587</td></tr>
-					<tr><th>SMTP Security</td> <td>STARTTLS <small>(&ldquo;always&rdquo; or &ldquo;required&rdquo;, if prompted)</small></td></tr>
+					<tr><th>SMTP Port</th> <td>465</td></tr>
+					<tr><th>SMTP Security</td> <td>SSL or TLS</td></tr>
 					<tr><th>Username:</th> <td>Your whole email address.</td></tr>
 					<tr><th>Password:</th> <td>Your mail password.</td></tr>
 					</table>
--- a/management/templates/system-backup.html
+++ b/management/templates/system-backup.html
@ -5,7 +5,7 @@

 <h2>Backup Status</h2>

-<p>The box makes an incremental backup each night. By default the backup is stored on the machine itself, but you can also have it stored on Amazon S3.</p>
+<p>The box makes an incremental backup each night. By default the backup is stored on the machine itself, but you can also store in on S3-compatible services like Amazon Web Services (AWS).</p>

 <h3>Configuration</h3>

@ -17,7 +17,7 @@
        <option value="off">Nowhere (Disable Backups)</option>
        <option value="local">{{hostname}}</option>
        <option value="rsync">rsync</option>
-        <option value="s3">Amazon S3</option>
+        <option value="s3">S3 (Amazon or compatible) </option>
        <option value="b2">Backblaze B2</option>
      </select>
    </div>
@ -73,8 +73,8 @@
  <!-- S3 BACKUP -->
  <div class="form-group backup-target-s3">
    <div class="col-sm-10 col-sm-offset-2">
-      <p>Backups are stored in an Amazon Web Services S3 bucket. You must have an AWS account already.</p>
-      <p>You MUST manually copy the encryption password from <tt class="backup-encpassword-file"></tt> to a safe and secure location. You will need this file to decrypt backup files. It is NOT stored in your Amazon S3 bucket.</p>
+      <p>Backups are stored in an S3-compatible bucket. You must have an AWS or other S3 service account already.</p>
+      <p>You MUST manually copy the encryption password from <tt class="backup-encpassword-file"></tt> to a safe and secure location. You will need this file to decrypt backup files. It is <b>NOT</b> stored in your S3 bucket.</p>
    </div>
  </div>
  <div class="form-group backup-target-s3">
@ -84,7 +84,7 @@
        {% for name, host in backup_s3_hosts %}
          <option value="{{host}}">{{name}}</option>
        {% endfor %}
-        <option value="other">Other</option>
+        <option value="other">Other (non AWS)</option>
      </select>
    </div>
  </div>
--- a/management/web_update.py
+++ b/management/web_update.py
@ -9,7 +9,7 @@ from dns_update import get_custom_dns_config, get_dns_zones
 from ssl_certificates import get_ssl_certificates, get_domain_ssl_files, check_certificate
 from utils import shell, safe_domain_name, sort_domains

-def get_web_domains(env, include_www_redirects=True, exclude_dns_elsewhere=True):
+def get_web_domains(env, include_www_redirects=True, include_auto=True, exclude_dns_elsewhere=True):
 	# What domains should we serve HTTP(S) for?
 	domains = set()

@ -18,15 +18,16 @@ def get_web_domains(env, include_www_redirects=True, exclude_dns_elsewhere=True)
 	# if the user wants to make one.
 	domains |= get_mail_domains(env)

-	if include_www_redirects:
+	if include_www_redirects and include_auto:
 		# Add 'www.' subdomains that we want to provide default redirects
 		# to the main domain for. We'll add 'www.' to any DNS zones, i.e.
 		# the topmost of each domain we serve.
 		domains |= set('www.' + zone for zone, zonefile in get_dns_zones(env))

+	if include_auto:
 		# Add Autoconfiguration domains for domains that there are user accounts at:
 		# 'autoconfig.' for Mozilla Thunderbird auto setup.
-	# 'autodiscover.' for Activesync autodiscovery.
+		# 'autodiscover.' for ActiveSync autodiscovery (Z-Push).
 		domains |= set('autoconfig.' + maildomain for maildomain in get_mail_domains(env, users_only=True))
 		domains |= set('autodiscover.' + maildomain for maildomain in get_mail_domains(env, users_only=True))

@ -160,17 +161,27 @@ def make_domain_config(domain, templates, ssl_certificates, env):
 			for path, url in yaml.get("proxies", {}).items():
 				# Parse some flags in the fragment of the URL.
 				pass_http_host_header = False
+				proxy_redirect_off = False
+				frame_options_header_sameorigin = False
 				m = re.search("#(.*)$", url)
 				if m:
 					for flag in m.group(1).split(","):
 						if flag == "pass-http-host":
 							pass_http_host_header = True
+						elif flag == "no-proxy-redirect":
+							proxy_redirect_off = True
+						elif flag == "frame-options-sameorigin":
+							frame_options_header_sameorigin = True
 					url = re.sub("#(.*)$", "", url)

 				nginx_conf_extra += "\tlocation %s {" % path
 				nginx_conf_extra += "\n\t\tproxy_pass %s;" % url
+				if proxy_redirect_off:
+					nginx_conf_extra += "\n\t\tproxy_redirect off;"
 				if pass_http_host_header:
 					nginx_conf_extra += "\n\t\tproxy_set_header Host $http_host;"
+				if frame_options_header_sameorigin:
+					nginx_conf_extra += "\n\t\tproxy_set_header X-Frame-Options SAMEORIGIN;"
 				nginx_conf_extra += "\n\t\tproxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;"
 				nginx_conf_extra += "\n\t\tproxy_set_header X-Forwarded-Host $http_host;"
 				nginx_conf_extra += "\n\t\tproxy_set_header X-Forwarded-Proto $scheme;"
@ -251,3 +262,4 @@ def get_web_domains_info(env):
 		}
 		for domain in get_web_domains(env)
 	]
+
--- a/security.md
+++ b/security.md
@ -32,7 +32,7 @@ The box's administrator and its (non-administrative) mail users must sometimes c

 These services are protected by [TLS](https://en.wikipedia.org/wiki/Transport_Layer_Security):

-* SMTP Submission (port 587). Mail users submit outbound mail through SMTP with STARTTLS on port 587.
+* SMTP Submission (ports 465/587). Mail users submit outbound mail through SMTP with TLS (port 465) or STARTTLS (port 587).
 * IMAP/POP (ports 993, 995). Mail users check for incoming mail through IMAP or POP over TLS.
 * HTTPS (port 443). Webmail, the Exchange/ActiveSync protocol, the administrative control panel, and any static hosted websites are accessed over HTTPS.

@ -44,7 +44,7 @@ The services all follow these rules:

 Additionally:

-* SMTP Submission (port 587) will not accept user credentials without STARTTLS (true also of SMTP on port 25 in case of client misconfiguration), and the submission port won't accept mail without encryption. The minimum cipher key length is 128 bits. (The box is of course configured not to be an open relay. User credentials are required to send outbound mail.) ([source](setup/mail-postfix.sh))
+* SMTP Submission on port 587 will not accept user credentials without STARTTLS (true also of SMTP on port 25 in case of client misconfiguration), and the submission port won't accept mail without encryption. The minimum cipher key length is 128 bits. (The box is of course configured not to be an open relay. User credentials are required to send outbound mail.) ([source](setup/mail-postfix.sh))
 * HTTPS (port 443): The HTTPS Strict Transport Security header is set. A redirect from HTTP to HTTPS is offered. The [Qualys SSL Labs test](https://www.ssllabs.com/ssltest) should report an A+ grade. ([source 1](conf/nginx-ssl.conf), [source 2](conf/nginx.conf))

 ### Password Storage
--- a/setup/bootstrap.sh
+++ b/setup/bootstrap.sh
@ -18,11 +18,11 @@ if [ -z "$TAG" ]; then
 	# space, but if we put it in a comment it would confuse the status checks!)
 	# to get the latest version, so the first such line must be the one that we
 	# want to display in status checks.
-	if [ "`lsb_release -d | sed 's/.*:\s*//' | sed 's/18\.04\.[0-9]/18.04/' `" == "Ubuntu 18.04 LTS" ]; then
+	if [ "$(lsb_release -d | sed 's/.*:\s*//' | sed 's/18\.04\.[0-9]/18.04/' )" == "Ubuntu 18.04 LTS" ]; then
 		# This machine is running Ubuntu 18.04.
-		TAG=v0.52
+		TAG=v0.53a

-	elif [ "`lsb_release -d | sed 's/.*:\s*//' | sed 's/14\.04\.[0-9]/14.04/' `" == "Ubuntu 14.04 LTS" ]; then
+	elif [ "$(lsb_release -d | sed 's/.*:\s*//' | sed 's/14\.04\.[0-9]/14.04/' )" == "Ubuntu 14.04 LTS" ]; then
 		# This machine is running Ubuntu 14.04.
 		echo "You are installing the last version of Mail-in-a-Box that will"
 		echo "support Ubuntu 14.04. If this is a new installation of Mail-in-a-Box,"
@ -68,11 +68,11 @@ fi
 cd $HOME/mailinabox

 # Update it.
-if [ "$TAG" != `git describe` ]; then
+if [ "$TAG" != $(git describe) ]; then
 	echo Updating Mail-in-a-Box to $TAG . . .
 	git fetch --depth 1 --force --prune origin tag $TAG
 	if ! git checkout -q $TAG; then
-		echo "Update failed. Did you modify something in `pwd`?"
+		echo "Update failed. Did you modify something in $(pwd)?"
 		exit 1
 	fi
 	echo
--- a/setup/dns.sh
+++ b/setup/dns.sh
@ -68,27 +68,15 @@ echo "include: /etc/nsd/zones.conf" >> /etc/nsd/nsd.conf;

 mkdir -p "$STORAGE_ROOT/dns/dnssec";

-# TLDs don't all support the same algorithms, so we'll generate keys using a few
-# different algorithms. RSASHA1-NSEC3-SHA1 was possibly the first widely used
-# algorithm that supported NSEC3, which is a security best practice. However TLDs
-# will probably be moving away from it to a a SHA256-based algorithm.
-#
-# Supports `RSASHA1-NSEC3-SHA1` (didn't test with `RSASHA256`):
-#
-#  * .info
-#  * .me
-#
-# Requires `RSASHA256`
-#
-#  * .email
-#  * .guide
-#
-# Supports `RSASHA256` (and defaulting to this)
-#
-#  * .fund
-
+# TLDs, registrars, and validating nameservers don't all support the same algorithms,
+# so we'll generate keys using a few different algorithms so that dns_update.py can
+# choose which algorithm to use when generating the zonefiles. See #1953 for recent
+# discussion. File for previously used algorithms (i.e. RSASHA1-NSEC3-SHA1) may still
+# be in the output directory, and we'll continue to support signing zones with them
+# so that trust isn't broken with deployed DS records, but we won't generate those
+# keys on new systems.
 FIRST=1 #NODOC
-for algo in RSASHA1-NSEC3-SHA1 RSASHA256; do
+for algo in RSASHA256 ECDSAP256SHA256; do
 if [ ! -f "$STORAGE_ROOT/dns/dnssec/$algo.conf" ]; then
 	if [ $FIRST == 1 ]; then
 		echo "Generating DNSSEC signing keys..."
@ -105,17 +93,22 @@ if [ ! -f "$STORAGE_ROOT/dns/dnssec/$algo.conf" ]; then
 	# ldns-keygen uses /dev/random for generating random numbers by default.
 	# This is slow and unecessary if we ensure /dev/urandom is seeded properly,
 	# so we use /dev/urandom. See system.sh for an explanation. See #596, #115.
-	KSK=$(umask 077; cd $STORAGE_ROOT/dns/dnssec; ldns-keygen -r /dev/urandom -a $algo -b 2048 -k _domain_);
+	# (This previously used -b 2048 but it's unclear if this setting makes sense
+	# for non-RSA keys, so it's removed. The RSA-based keys are not recommended
+	# anymore anyway.)
+	KSK=$(umask 077; cd $STORAGE_ROOT/dns/dnssec; ldns-keygen -r /dev/urandom -a $algo -k _domain_);

 	# Now create a Zone-Signing Key (ZSK) which is expected to be
 	# rotated more often than a KSK, although we have no plans to
 	# rotate it (and doing so would be difficult to do without
-	# disturbing DNS availability.) Omit `-k` and use a shorter key length.
-	ZSK=$(umask 077; cd $STORAGE_ROOT/dns/dnssec; ldns-keygen -r /dev/urandom -a $algo -b 1024 _domain_);
+	# disturbing DNS availability.) Omit `-k`.
+	# (This previously used -b 1024 but it's unclear if this setting makes sense
+	# for non-RSA keys, so it's removed.)
+	ZSK=$(umask 077; cd $STORAGE_ROOT/dns/dnssec; ldns-keygen -r /dev/urandom -a $algo _domain_);

 	# These generate two sets of files like:
 	#
-	# * `K_domain_.+007+08882.ds`: DS record normally provided to domain name registrar (but it's actually invalid with `_domain_`)
+	# * `K_domain_.+007+08882.ds`: DS record normally provided to domain name registrar (but it's actually invalid with `_domain_` so we don't use this file)
 	# * `K_domain_.+007+08882.key`: public key
 	# * `K_domain_.+007+08882.private`: private key (secret!)

@ -139,7 +132,7 @@ cat > /etc/cron.daily/mailinabox-dnssec << EOF;
 #!/bin/bash
 # Mail-in-a-Box
 # Re-sign any DNS zones with DNSSEC because the signatures expire periodically.
-`pwd`/tools/dns_update
+$(pwd)/tools/dns_update
 EOF
 chmod +x /etc/cron.daily/mailinabox-dnssec

--- a/setup/firstuser.sh
+++ b/setup/firstuser.sh
@ -1,5 +1,5 @@
 # If there aren't any mail users yet, create one.
-if [ -z "`management/cli.py user`" ]; then
+if [ -z "$(management/cli.py user)" ]; then
 	# The outut of "management/cli.py user" is a list of mail users. If there
 	# aren't any yet, it'll be empty.

@ -10,7 +10,7 @@ if [ -z "`management/cli.py user`" ]; then
 			input_box "Mail Account" \
 				"Let's create your first mail account.
 				\n\nWhat email address do you want?" \
-				me@`get_default_hostname` \
+				me@$(get_default_hostname) \
 				EMAIL_ADDR

 			if [ -z "$EMAIL_ADDR" ]; then
--- a/setup/functions.sh
+++ b/setup/functions.sh
@ -9,12 +9,12 @@ function hide_output {
 	# and returns a non-zero exit code.

 	# Get a temporary file.
-	OUTPUT=$(tempfile)
+	OUTPUT=$(mktemp)

 	# Execute command, redirecting stderr/stdout to the temporary file. Since we
 	# check the return code ourselves, disable 'set -e' temporarily.
 	set +e
-	$@ &> $OUTPUT
+	"$@" &> $OUTPUT
 	E=$?
 	set -e

@ -22,7 +22,7 @@ function hide_output {
 	if [ $E != 0 ]; then
 		# Something failed.
 		echo
-		echo FAILED: $@
+		echo FAILED: "$@"
 		echo -----------------------------------------
 		cat $OUTPUT
 		echo -----------------------------------------
@ -53,8 +53,7 @@ function apt_install {
 	# install' for all of the packages.  Calling `dpkg` on each package is slow,
 	# and doesn't affect what we actually do, except in the messages, so let's
 	# not do that anymore.
-	PACKAGES=$@
-	apt_get_quiet install $PACKAGES
+	apt_get_quiet install "$@"
 }

 function get_default_hostname {
--- a/setup/mail-dovecot.sh
+++ b/setup/mail-dovecot.sh
@ -45,8 +45,8 @@ apt_install \
 # - https://www.dovecot.org/list/dovecot/2012-August/137569.html
 # - https://www.dovecot.org/list/dovecot/2011-December/132455.html
 tools/editconf.py /etc/dovecot/conf.d/10-master.conf \
-	default_process_limit=$(echo "`nproc` * 250" | bc) \
-	default_vsz_limit=$(echo "`free -tm  | tail -1 | awk '{print $2}'` / 3" | bc)M \
+	default_process_limit=$(echo "$(nproc) * 250" | bc) \
+	default_vsz_limit=$(echo "$(free -tm  | tail -1 | awk '{print $2}') / 3" | bc)M \
 	log_path=/var/log/mail.log

 # The inotify `max_user_instances` default is 128, which constrains
@ -183,6 +183,7 @@ plugin {
  sieve_after = $STORAGE_ROOT/mail/sieve/global_after
  sieve = $STORAGE_ROOT/mail/sieve/%d/%n.sieve
  sieve_dir = $STORAGE_ROOT/mail/sieve/%d/%n
+  sieve_redirect_envelope_from = recipient
 }
 EOF

--- a/setup/mail-postfix.sh
+++ b/setup/mail-postfix.sh
@ -17,7 +17,7 @@
 # LMTP. Spamassassin then passes mail over to Dovecot for
 # storage in the user's mailbox.
 #
-# Postfix also listens on port 587 (SMTP+STARTLS) for
+# Postfix also listens on ports 465/587 (SMTPS, SMTP+STARTLS) for
 # connections from users who can authenticate and then sends
 # their email out to the outside world. Postfix queries Dovecot
 # to authenticate users.
@ -71,7 +71,7 @@ tools/editconf.py /etc/postfix/main.cf \

 # ### Outgoing Mail

-# Enable the 'submission' port 587 smtpd server and tweak its settings.
+# Enable the 'submission' ports 465 and 587 and tweak their settings.
 #
 # * Enable authentication. It's disabled globally so that it is disabled on port 25,
 #   so we need to explicitly enable it here.
@ -80,13 +80,19 @@ tools/editconf.py /etc/postfix/main.cf \
 #   OpenDKIM milter only. See dkim.sh.
 # * Even though we dont allow auth over non-TLS connections (smtpd_tls_auth_only below, and without auth the client cant
 #   send outbound mail), don't allow non-TLS mail submission on this port anyway to prevent accidental misconfiguration.
-#   Setting smtpd_tls_security_level=encrypt also triggers the use of the 'mandatory' settings below.
+#   Setting smtpd_tls_security_level=encrypt also triggers the use of the 'mandatory' settings below (but this is ignored with smtpd_tls_wrappermode=yes.)
 # * Give it a different name in syslog to distinguish it from the port 25 smtpd server.
 # * Add a new cleanup service specific to the submission service ('authclean')
 #   that filters out privacy-sensitive headers on mail being sent out by
 #   authenticated users.  By default Postfix also applies this to attached
 #   emails but we turn this off by setting nested_header_checks empty.
 tools/editconf.py /etc/postfix/master.cf -s -w \
+	"smtps=inet n       -       -       -       -       smtpd
+	  -o smtpd_tls_wrappermode=yes
+	  -o smtpd_sasl_auth_enable=yes
+	  -o syslog_name=postfix/submission
+	  -o smtpd_milters=inet:127.0.0.1:8891
+	  -o cleanup_service_name=authclean" \
 	"submission=inet n       -       -       -       -       smtpd
 	  -o smtpd_sasl_auth_enable=yes
 	  -o syslog_name=postfix/submission
@ -107,7 +113,7 @@ sed -i "s/PRIMARY_HOSTNAME/$PRIMARY_HOSTNAME/" /etc/postfix/outgoing_mail_header
 sed -i "s/PUBLIC_IP/$PUBLIC_IP/" /etc/postfix/outgoing_mail_header_filters

 # Enable TLS on incoming connections. It is not required on port 25, allowing for opportunistic
-# encryption. On port 587 it is mandatory (see above). Shared and non-shared settings are
+# encryption. On ports 465 and 587 it is mandatory (see above). Shared and non-shared settings are
 # given here. Shared settings include:
 # * Require TLS before a user is allowed to authenticate.
 # * Set the path to the server TLS certificate and 2048-bit DH parameters for old DH ciphers.
@ -117,9 +123,6 @@ sed -i "s/PUBLIC_IP/$PUBLIC_IP/" /etc/postfix/outgoing_mail_header_filters
 #   won't fall back to cleartext. So we don't disable too much. smtpd_tls_exclude_ciphers applies to
 #   both port 25 and port 587, but because we override the cipher list for both, it probably isn't used.
 #   Use Mozilla's "Old" recommendations at https://ssl-config.mozilla.org/#server=postfix&server-version=3.3.0&config=old&openssl-version=1.1.1
-# For port 587 (via the 'mandatory' settings):
-# * Use Mozilla's "Intermediate" TLS recommendations from https://ssl-config.mozilla.org/#server=postfix&server-version=3.3.0&config=intermediate&openssl-version=1.1.1
-#   using and overriding the "high" cipher list so we don't conflict with the more permissive settings for port 25.
 tools/editconf.py /etc/postfix/main.cf \
 	smtpd_tls_security_level=may\
 	smtpd_tls_auth_only=yes \
@ -130,18 +133,23 @@ tools/editconf.py /etc/postfix/main.cf \
 	smtpd_tls_ciphers=medium \
 	tls_medium_cipherlist=ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA:ECDHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA256:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:AES128-SHA:AES256-SHA:DES-CBC3-SHA \
 	smtpd_tls_exclude_ciphers=aNULL,RC4 \
+	tls_preempt_cipherlist=no \
+	smtpd_tls_received_header=yes
+
+# For ports 465/587 (via the 'mandatory' settings):
+# * Use Mozilla's "Intermediate" TLS recommendations from https://ssl-config.mozilla.org/#server=postfix&server-version=3.3.0&config=intermediate&openssl-version=1.1.1
+#   using and overriding the "high" cipher list so we don't conflict with the more permissive settings for port 25.
+tools/editconf.py /etc/postfix/main.cf \
 	smtpd_tls_mandatory_protocols="!SSLv2,!SSLv3,!TLSv1,!TLSv1.1" \
 	smtpd_tls_mandatory_ciphers=high \
 	tls_high_cipherlist=ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384 \
-	smtpd_tls_mandatory_exclude_ciphers=aNULL,DES,3DES,MD5,DES+MD5,RC4 \
-	tls_preempt_cipherlist=no \
-	smtpd_tls_received_header=yes
+	smtpd_tls_mandatory_exclude_ciphers=aNULL,DES,3DES,MD5,DES+MD5,RC4

 # Prevent non-authenticated users from sending mail that requires being
 # relayed elsewhere. We don't want to be an "open relay". On outbound
 # mail, require one of:
 #
-# * `permit_sasl_authenticated`: Authenticated users (i.e. on port 587).
+# * `permit_sasl_authenticated`: Authenticated users (i.e. on port 465/587).
 # * `permit_mynetworks`: Mail that originates locally.
 # * `reject_unauth_destination`: No one else. (Permits mail whose destination is local and rejects other mail.)
 tools/editconf.py /etc/postfix/main.cf \
@ -191,7 +199,7 @@ tools/editconf.py /etc/postfix/main.cf \
 #
 # In a basic setup we would pass mail directly to Dovecot by setting
 # virtual_transport to `lmtp:unix:private/dovecot-lmtp`.
-tools/editconf.py /etc/postfix/main.cf virtual_transport=lmtp:[127.0.0.1]:10025
+tools/editconf.py /etc/postfix/main.cf "virtual_transport=lmtp:[127.0.0.1]:10025"
 # Because of a spampd bug, limit the number of recipients in each connection.
 # See https://github.com/mail-in-a-box/mailinabox/issues/1523.
 tools/editconf.py /etc/postfix/main.cf lmtp_destination_recipient_limit=1
@ -261,6 +269,7 @@ tools/editconf.py /etc/postfix/main.cf \
 # Allow the two SMTP ports in the firewall.

 ufw_allow smtp
+ufw_allow smtps
 ufw_allow submission

 # Restart services
--- a/setup/management.sh
+++ b/setup/management.sh
@ -97,7 +97,7 @@ export LANG=en_US.UTF-8
 export LC_TYPE=en_US.UTF-8

 source $venv/bin/activate
-exec python `pwd`/management/daemon.py
+exec python $(pwd)/management/daemon.py
 EOF
 chmod +x $inst_dir/start
 cp --remove-destination conf/mailinabox.service /lib/systemd/system/mailinabox.service # target was previously a symlink so remove it first
@ -112,7 +112,7 @@ minute=$((RANDOM % 60))  # avoid overloading mailinabox.email
 cat > /etc/cron.d/mailinabox-nightly << EOF;
 # Mail-in-a-Box --- Do not edit / will be overwritten on update.
 # Run nightly tasks: backup, status checks.
-$minute 3 * * *	root	(cd `pwd` && management/daily_tasks.sh)
+$minute 3 * * *	root	(cd $(pwd) && management/daily_tasks.sh)
 EOF

 # Start the management server.
--- a/setup/nextcloud.sh
+++ b/setup/nextcloud.sh
@ -97,12 +97,12 @@ InstallNextcloud() {
 }

 # Nextcloud Version to install. Checks are done down below to step through intermediate versions.
-nextcloud_ver=20.0.1
-nextcloud_hash=f2b3faa570c541df73f209e873a1c2852e79eab8
-contacts_ver=3.4.1
-contacts_hash=aee680a75e95f26d9285efd3c1e25cf7f3bfd27e
-calendar_ver=2.1.2
-calendar_hash=930c07863bb7a65652dec34793802c8d80502336
+nextcloud_ver=20.0.8
+nextcloud_hash=372b0b4bb07c7984c04917aff86b280e68fbe761
+contacts_ver=3.5.1
+contacts_hash=d2ffbccd3ed89fa41da20a1dff149504c3b33b93
+calendar_ver=2.2.0
+calendar_hash=673ad72ca28adb8d0f209015ff2dca52ffad99af
 user_external_ver=1.0.0
 user_external_hash=3bf2609061d7214e7f0f69dd8883e55c4ec8f50a

@ -128,7 +128,7 @@ if [ ! -d /usr/local/lib/owncloud/ ] || [[ ! ${CURRENT_NEXTCLOUD_VER} =~ ^$nextc

 	# Backup the existing ownCloud/Nextcloud.
 	# Create a backup directory to store the current installation and database to
-	BACKUP_DIRECTORY=$STORAGE_ROOT/owncloud-backup/`date +"%Y-%m-%d-%T"`
+	BACKUP_DIRECTORY=$STORAGE_ROOT/owncloud-backup/$(date +"%Y-%m-%d-%T")
 	mkdir -p "$BACKUP_DIRECTORY"
 	if [ -d /usr/local/lib/owncloud/ ]; then
 		echo "Upgrading Nextcloud --- backing up existing installation, configuration, and database to directory to $BACKUP_DIRECTORY..."
@ -312,7 +312,9 @@ sudo -u www-data php /usr/local/lib/owncloud/occ upgrade
 if [ \( $? -ne 0 \) -a \( $? -ne 3 \) ]; then exit 1; fi

 # Disable default apps that we don't support
-sudo -u www-data php /usr/local/lib/owncloud/occ app:disable photos dashboard activity
+sudo -u www-data \
+	php /usr/local/lib/owncloud/occ app:disable photos dashboard activity \
+	| (grep -v "No such app enabled" || /bin/true)

 # Set PHP FPM values to support large file uploads
 # (semicolon is the comment character in this file, hashes produce deprecation warnings)
--- a/setup/preflight.sh
+++ b/setup/preflight.sh
@ -8,7 +8,7 @@ if [[ $EUID -ne 0 ]]; then
 fi

 # Check that we are running on Ubuntu 18.04 LTS (or 18.04.xx).
-if [ "`lsb_release -d | sed 's/.*:\s*//' | sed 's/18\.04\.[0-9]/18.04/' `" != "Ubuntu 18.04 LTS" ]; then
+if [ "$(lsb_release -d | sed 's/.*:\s*//' | sed 's/18\.04\.[0-9]/18.04/' )" != "Ubuntu 18.04 LTS" ]; then
 	echo "Mail-in-a-Box only supports being installed on Ubuntu 18.04, sorry. You are running:"
 	echo
 	lsb_release -d | sed 's/.*:\s*//'
--- a/setup/ssl.sh
+++ b/setup/ssl.sh
@ -10,7 +10,7 @@
 #
 #  * DNSSEC DANE TLSA records
 #  * IMAP
-#  * SMTP (opportunistic TLS for port 25 and submission on port 587)
+#  * SMTP (opportunistic TLS for port 25 and submission on ports 465/587)
 #  * HTTPS
 #
 # The certificate is created with its CN set to the PRIMARY_HOSTNAME. It is
--- a/setup/start.sh
+++ b/setup/start.sh
@ -46,7 +46,7 @@ fi
 # in the first dialog prompt, so we should do this before that starts.
 cat > /usr/local/bin/mailinabox << EOF;
 #!/bin/bash
-cd `pwd`
+cd $(pwd)
 source setup/start.sh
 EOF
 chmod +x /usr/local/bin/mailinabox
@ -78,7 +78,7 @@ if [ ! -d $STORAGE_ROOT ]; then
 	mkdir -p $STORAGE_ROOT
 fi
 if [ ! -f $STORAGE_ROOT/mailinabox.version ]; then
-	echo $(setup/migrate.py --current) > $STORAGE_ROOT/mailinabox.version
+	setup/migrate.py --current > $STORAGE_ROOT/mailinabox.version
 	chown $STORAGE_USER.$STORAGE_USER $STORAGE_ROOT/mailinabox.version
 fi

@ -94,7 +94,7 @@ PUBLIC_IP=$PUBLIC_IP
 PUBLIC_IPV6=$PUBLIC_IPV6
 PRIVATE_IP=$PRIVATE_IP
 PRIVATE_IPV6=$PRIVATE_IPV6
-MTA_STS_MODE=${MTA_STS_MODE-}
+MTA_STS_MODE=${DEFAULT_MTA_STS_MODE:-enforce}
 EOF

 # Start service configuration.
--- a/setup/web.sh
+++ b/setup/web.sh
@ -126,13 +126,13 @@ chmod a+r /var/lib/mailinabox/mozilla-autoconfig.xml
 # nginx configuration at /.well-known/mta-sts.txt
 # more documentation is available on: 
 # https://www.uriports.com/blog/mta-sts-explained/
-# default mode is "enforce". Change to "testing" which means
-# "Messages will be delivered as though there was no failure
-# but a report will be sent if TLS-RPT is configured" if you
-# are not sure you want this yet. Or "none".
+# default mode is "enforce". In /etc/mailinabox.conf change
+# "MTA_STS_MODE=testing" which means "Messages will be delivered
+# as though there was no failure but a report will be sent if
+# TLS-RPT is configured" if you are not sure you want this yet. Or "none".
 PUNY_PRIMARY_HOSTNAME=$(echo "$PRIMARY_HOSTNAME" | idn2)
 cat conf/mta-sts.txt \
-        | sed "s/MODE/${MTA_STS_MODE:-enforce}/" \
+        | sed "s/MODE/${MTA_STS_MODE}/" \
        | sed "s/PRIMARY_HOSTNAME/$PUNY_PRIMARY_HOSTNAME/" \
         > /var/lib/mailinabox/mta-sts.txt
 chmod a+r /var/lib/mailinabox/mta-sts.txt
--- a/setup/webmail.sh
+++ b/setup/webmail.sh
@ -47,7 +47,7 @@ needs_update=0 #NODOC
 if [ ! -f /usr/local/lib/roundcubemail/version ]; then
 	# not installed yet #NODOC
 	needs_update=1 #NODOC
-elif [[ "$UPDATE_KEY" != `cat /usr/local/lib/roundcubemail/version` ]]; then
+elif [[ "$UPDATE_KEY" != $(cat /usr/local/lib/roundcubemail/version) ]]; then
 	# checks if the version is what we want
 	needs_update=1 #NODOC
 fi
@ -91,8 +91,9 @@ fi

 # ### Configuring Roundcube

-# Generate a safe 24-character secret key of safe characters.
-SECRET_KEY=$(dd if=/dev/urandom bs=1 count=18 2>/dev/null | base64 | fold -w 24 | head -n 1)
+# Generate a secret key of PHP-string-safe characters appropriate
+# for the cipher algorithm selected below.
+SECRET_KEY=$(dd if=/dev/urandom bs=1 count=32 2>/dev/null | base64 | sed s/=//g)

 # Create a configuration file.
 #
@ -126,7 +127,8 @@ cat > $RCM_CONFIG <<EOF;
 );
 \$config['support_url'] = 'https://mailinabox.email/';
 \$config['product_name'] = '$PRIMARY_HOSTNAME Webmail';
-\$config['des_key'] = '$SECRET_KEY';
+\$config['cipher_method'] = 'AES-256-CBC'; # persistent login cookie and potentially other things
+\$config['des_key'] = '$SECRET_KEY'; # 37 characters -> ~256 bits for AES-256, see above
 \$config['plugins'] = array('html5_notifier', 'archive', 'zipdownload', 'password', 'managesieve', 'jqueryui', 'persistent_login', 'carddav');
 \$config['skin'] = 'elastic';
 \$config['login_autocomplete'] = 2;
--- a/setup/zpush.sh
+++ b/setup/zpush.sh
@ -23,22 +23,22 @@ phpenmod -v php imap

 # Copy Z-Push into place.
 VERSION=2.6.2
-TARGETHASH=4b312d64227ef887b24d9cc8f0ae17519586f6e2
+TARGETHASH=f0e8091a8030e5b851f5ba1f9f0e1a05b8762d80
 needs_update=0 #NODOC
 if [ ! -f /usr/local/lib/z-push/version ]; then
 	needs_update=1 #NODOC
-elif [[ $VERSION != `cat /usr/local/lib/z-push/version` ]]; then
+elif [[ $VERSION != $(cat /usr/local/lib/z-push/version) ]]; then
 	# checks if the version
 	needs_update=1 #NODOC
 fi
 if [ $needs_update == 1 ]; then
 	# Download
-	wget_verify "https://stash.z-hub.io/rest/api/latest/projects/ZP/repos/z-push/archive?at=refs%2Ftags%2F$VERSION&format=zip" $TARGETHASH /tmp/z-push.zip
+	wget_verify "https://github.com/Z-Hub/Z-Push/archive/refs/tags/$VERSION.zip" $TARGETHASH /tmp/z-push.zip

 	# Extract into place.
 	rm -rf /usr/local/lib/z-push /tmp/z-push
 	unzip -q /tmp/z-push.zip -d /tmp/z-push
-	mv /tmp/z-push/src /usr/local/lib/z-push
+	mv /tmp/z-push/*/src /usr/local/lib/z-push
 	rm -rf /tmp/z-push.zip /tmp/z-push

 	rm -f /usr/sbin/z-push-{admin,top}
--- a/tests/test_mail.py
+++ b/tests/test_mail.py
@ -41,9 +41,8 @@ This is a test message. It should be automatically deleted by the test script.""
 	)

 # Connect to the server on the SMTP submission TLS port.
-server = smtplib.SMTP(host, 587)
+server = smtplib.SMTP_SSL(host)
 #server.set_debuglevel(1)
-server.starttls()

 # Verify that the EHLO name matches the server's reverse DNS.
 ipaddr = socket.gethostbyname(host) # IPv4 only!