Added key rollover code.

management/daemon.py

@@ -364,6 +364,77 @@ def ssl_get_csr(domain):
 	ssl_private_key = os.path.join(os.path.join(env["STORAGE_ROOT"], 'ssl', 'ssl_private_key.pem'))
 	return create_csr(domain, ssl_private_key, request.form.get('countrycode', ''), env)
 
+@app.route('/ssl/renew/<domain>', methods=['POST'])
+@authorized_personnel_only
+def ssl_renew(domain):
+	from exclusiveprocess import Lock
+	from utils import load_environment
+	from ssl_certificates import provision_certificates
+	existing_key = request.form.get('existing_key')
+	Lock(die=True).forever()
+	env = load_environment()
+	if existing_key == "yes":
+		status = provision_certificates(env, limit_domains=[], domain_to_be_renewed=domain)
+		app.logger.warning("renew without new key=", status)  # TODO: remove this line after testing
+	elif existing_key == "no":
+		import glob
+		try:
+			# steps followed
+			# 1. take a backup of the current /home/user-data/ssl/ folder to be safe
+			# 2. renew all the existing certificates from CSR generated from the existing next_ssl_private_key
+			# 3. if the renew is successful, replace the current ssl_private_key with the next_ssl_private_key and
+			# 4. generate the next_ssl_private_key
+			# 5. if any error occurs, copy everything from the /home/user-data/ssl-backup folder to /home/user-data/ssl
+
+			# step 1
+			files = glob.glob(env["STORAGE_ROOT"] + "/ssl/*")
+			for file in files:
+				subprocess.check_output(["cp", "-r", file, env["STORAGE_ROOT"] + "/ssl-backup/"])
+
+			# step 2
+			status = provision_certificates(env, limit_domains=[], new_key=True)
+
+			# step 3 and 4 is in post_install_func method of ssl_certificates.py
+			app.logger.warning("renew with new key=", status)  # TODO: remove this line after proper testing
+		except Exception as e:
+			import traceback
+			files = glob.glob(env["STORAGE_ROOT"] + "/ssl-backup/*")
+			for file in files:
+				subprocess.check_output(["cp", "-r", file, env["STORAGE_ROOT"] + "/ssl/"])
+			app.logger.warning(traceback.print_exc())  # TODO: remove this line after proper testing
+			return json_response({
+				"title": "Error",
+				"log": "Sorry, something is not right!",
+			})
+	else:
+		return json_response({
+			"title": "Error",
+			"log": "Sorry, something is not right!",
+		})
+
+	for item in status:
+		if isinstance(status, str):
+			continue
+		else:
+			if domain in item['domains']:
+				if item['result'] == 'skipped':
+					return json_response({
+						"title": item["result"].capitalize(),
+						"log": "\n".join(item['log']),
+					})
+				elif item['result'] == 'installed':
+					return json_response({
+						"title": item["result"].capitalize(),
+						"log": "Your certificate containing these domains " + ",".join(
+							item['domains']) + " have been renewed",
+					})
+				else:
+					return json_response({
+						"title": item["result"].capitalize(),
+						"log": "\n".join(item['log'])
+					})
+
+
 @app.route('/ssl/install', methods=['POST'])
 @authorized_personnel_only
 def ssl_install_cert():
@@ -604,7 +675,8 @@ def log_failed_login(request):
 # APP
 
 if __name__ == '__main__':
-	if "DEBUG" in os.environ: app.debug = True
+	app.debug = True  # TODO: remove this line and uncomment the next line after testing
+	# if "DEBUG" in os.environ: app.debug = True
 	if "APIKEY" in os.environ: auth_service.key = os.environ["APIKEY"]
 
 	if not app.debug:

management/dns_update.py

@@ -174,9 +174,11 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en
 
 		# Add a DANE TLSA record for SMTP.
 		records.append(("_25._tcp", "TLSA", build_tlsa_record(env), "Recommended when DNSSEC is enabled. Advertises to mail servers connecting to the box that mandatory encryption should be used."))
+		records.append(("_25._tcp", "TLSA", build_tlsa_record(env, from_cert=False), "Recommended when DNSSEC is enabled. Advertises to mail servers connecting to the box that mandatory encryption should be used."))
 
 		# Add a DANE TLSA record for HTTPS, which some browser extensions might make use of.
 		records.append(("_443._tcp", "TLSA", build_tlsa_record(env), "Optional. When DNSSEC is enabled, provides out-of-band HTTPS certificate validation for a few web clients that support it."))
+		records.append(("_443._tcp", "TLSA", build_tlsa_record(env, from_cert=False), "Optional. When DNSSEC is enabled, provides out-of-band HTTPS certificate validation for a few web clients that support it."))
 
 		# Add a SSHFP records to help SSH key validation. One per available SSH key on this system.
 		for value in build_sshfp_records():
@@ -367,7 +369,7 @@ def build_zone(domain, all_domains, additional_records, www_redirect_domains, en
 
 ########################################################################
 
-def build_tlsa_record(env):
+def build_tlsa_record(env, from_cert=True):
 	# A DANE TLSA record in DNS specifies that connections on a port
 	# must use TLS and the certificate must match a particular criteria.
 	#
@@ -390,11 +392,16 @@ def build_tlsa_record(env):
 	from ssl_certificates import load_cert_chain, load_pem
 	from cryptography.hazmat.primitives.serialization import Encoding, PublicFormat
 
-	fn = os.path.join(env["STORAGE_ROOT"], "ssl", "ssl_certificate.pem")
+	if from_cert:
-	cert = load_pem(load_cert_chain(fn)[0])
+		fn = os.path.join(env["STORAGE_ROOT"], "ssl", "ssl_certificate.pem")
-
+		cert = load_pem(load_cert_chain(fn)[0])
-	subject_public_key = cert.public_key().public_bytes(Encoding.DER, PublicFormat.SubjectPublicKeyInfo)
+		subject_public_key = cert.public_key().public_bytes(Encoding.DER, PublicFormat.SubjectPublicKeyInfo)
-	# We could have also loaded ssl_private_key.pem and called priv_key.public_key().public_bytes(...)
+	else:
+		# this is for Double TLSA scheme of key rollover.
+		# More details here (https://mail.sys4.de/pipermail/dane-users/2018-February/000440.html)
+		fn = os.path.join(env["STORAGE_ROOT"], "ssl", "next_ssl_private_key.pem")
+		private_key = load_pem(open(fn, 'rb').read())
+		subject_public_key = private_key.public_key().public_bytes(Encoding.DER, PublicFormat.SubjectPublicKeyInfo)
 
 	pk_hash = hashlib.sha256(subject_public_key).hexdigest()
 
@@ -862,6 +869,8 @@ def set_custom_dns_record(qname, rtype, value, action, env):
 
 			if not re.search(DOMAIN_RE, value):
 				raise ValueError("Invalid value.")
+		elif rtype == "TLSA":
+			pass
 		elif rtype in ("CNAME", "TXT", "SRV", "MX", "SSHFP", "CAA"):
 			# anything goes
 			pass

management/ssl_certificates.py

@@ -45,7 +45,7 @@ def get_ssl_certificates(env):
 
 	# Remember stuff.
 	private_keys = { }
-	certificates = [ ]
+	certificates = []
 
 	# Scan each of the files to find private keys and certificates.
 	# We must load all of the private keys first before processing
@@ -73,6 +73,7 @@ def get_ssl_certificates(env):
 	domains = { }
 	for cert in certificates:
 		# What domains is this certificate good for?
+		# cert_domains = cert common name + all SANs, primary_domain = cert common name
 		cert_domains, primary_domain = get_certificate_domains(cert)
 		cert._primary_domain = primary_domain
 
@@ -186,8 +187,16 @@ def get_certificates_to_provision(env, limit_domains=None, show_valid_certs=True
 	from web_update import get_web_domains
 	from status_checks import query_dns, normalize_ip
 
+	# existing_certs = all valid certificates that are in /home/user-data/ssl or 1 level deep
+	# validity indicator -> private key exists for the cert public key?, not_expired?
+	# if multiple valid certs exist, then the one with the furthest expiry date and filename
+	# lexicographically smallest is returned
 	existing_certs = get_ssl_certificates(env)
 
+	# this function returns the list of domain names of all the email addresses and adds
+	# autoconfig, www, mta-sts, autodiscover subdomain to each of these domains
+	# if exclude_dns_elsewhere flag is set, then all the domains having A/AAAA record not on this machine
+	# are excluded
 	plausible_web_domains = get_web_domains(env, exclude_dns_elsewhere=False)
 	actual_web_domains = get_web_domains(env)
 
@@ -212,7 +221,8 @@ def get_certificates_to_provision(env, limit_domains=None, show_valid_certs=True
 			# how Let's Encrypt will connect.
 			bad_dns = []
 			for rtype, value in [("A", env["PUBLIC_IP"]), ("AAAA", env.get("PUBLIC_IPV6"))]:
-				if not value: continue # IPv6 is not configured
+				if not value:
+					continue  # IPv6 is not configured
 				response = query_dns(domain, rtype)
 				if response != normalize_ip(value):
 					bad_dns.append("%s (%s)" % (response, rtype))
@@ -226,6 +236,7 @@ def get_certificates_to_provision(env, limit_domains=None, show_valid_certs=True
 				# DNS is all good.
 
 				# Check for a good existing cert.
+				# existing_cert = existing cert for domain
 				existing_cert = get_domain_ssl_files(domain, existing_certs, env, use_main_cert=False, allow_missing_cert=True)
 				if existing_cert:
 					existing_cert_check = check_certificate(domain, existing_cert['certificate'], existing_cert['private-key'],
@@ -242,19 +253,30 @@ def get_certificates_to_provision(env, limit_domains=None, show_valid_certs=True
 
 	return (domains_to_provision, domains_cant_provision)
 
-def provision_certificates(env, limit_domains):
+def provision_certificates(env, limit_domains, domain_to_be_renewed=None, new_key=False):
 	# What domains should we provision certificates for? And what
 	# errors prevent provisioning for other domains.
-	domains, domains_cant_provision = get_certificates_to_provision(env, limit_domains=limit_domains)
-
-	# Build a list of what happened on each domain or domain-set.
 	ret = []
-	for domain, error in domains_cant_provision.items():
+	is_tlsa_update_required = False
-		ret.append({
+	if new_key:
-			"domains": [domain],
+		from web_update import get_web_domains
-			"log": [error],
+		domains = get_web_domains(env)
-			"result": "skipped",
+	elif domain_to_be_renewed:
-		})
+		existing_certs = get_ssl_certificates(env)
+		existing_cert = get_domain_ssl_files(domain_to_be_renewed, existing_certs, env, use_main_cert=False, allow_missing_cert=True)
+		domains, primary_domain = get_certificate_domains(load_pem(load_cert_chain(existing_cert["certificate"])[0]))
+	else:
+		# domains = domains for which a certificate can be provisioned
+		# domains_cant_provision = domains for which a certificate can't be provisioned and the reason
+		domains, domains_cant_provision = get_certificates_to_provision(env, limit_domains=limit_domains)
+
+		# Build a list of what happened on each domain or domain-set.
+		for domain, error in domains_cant_provision.items():
+			ret.append({
+				"domains": [domain],
+				"log": [error],
+				"result": "skipped",
+			})
 
 	# Break into groups by DNS zone: Group every domain with its parent domain, if
 	# its parent domain is in the list of domains to request a certificate for.
@@ -309,6 +331,8 @@ def provision_certificates(env, limit_domains):
 			# Create a CSR file for our master private key so that certbot
 			# uses our private key.
 			key_file = os.path.join(env['STORAGE_ROOT'], 'ssl', 'ssl_private_key.pem')
+			if new_key:
+				key_file = os.path.join(env['STORAGE_ROOT'], 'ssl', 'next_ssl_private_key.pem')
 			with tempfile.NamedTemporaryFile() as csr_file:
 				# We could use openssl, but certbot requires
 				# that the CN domain and SAN domains match
@@ -345,9 +369,9 @@ def provision_certificates(env, limit_domains):
 						"certbot",
 						"certonly",
 						#"-v", # just enough to see ACME errors
-						"--non-interactive", # will fail if user hasn't registered during Mail-in-a-Box setup
+						"--non-interactive",  # will fail if user hasn't registered during Mail-in-a-Box setup
 
-						"-d", ",".join(domain_list), # first will be main domain
+						"-d", ",".join(domain_list),  # first will be main domain
 
 						"--csr", csr_file.name, # use our private key; unfortunately this doesn't work with auto-renew so we need to save cert manually
 						"--cert-path", os.path.join(d, 'cert'), # we only use the full chain
@@ -363,6 +387,8 @@ def provision_certificates(env, limit_domains):
 
 			ret[-1]["log"].append(certbotret)
 			ret[-1]["result"] = "installed"
+			if new_key and env['PRIMARY_HOSTNAME'] in domains:
+				is_tlsa_update_required = True
 		except subprocess.CalledProcessError as e:
 			ret[-1]["log"].append(e.output.decode("utf8"))
 			ret[-1]["result"] = "error"
@@ -371,7 +397,7 @@ def provision_certificates(env, limit_domains):
 			ret[-1]["result"] = "error"
 
 	# Run post-install steps.
-	ret.extend(post_install_func(env))
+	ret.extend(post_install_func(env, is_tlsa_update_required=is_tlsa_update_required))
 
 	# Return what happened with each certificate request.
 	return ret
@@ -466,7 +492,7 @@ def install_cert_copy_file(fn, env):
 	shutil.move(fn, ssl_certificate)
 
 
-def post_install_func(env):
+def post_install_func(env, is_tlsa_update_required=False):
 	ret = []
 
 	# Get the certificate to use for PRIMARY_HOSTNAME.
@@ -496,6 +522,25 @@ def post_install_func(env):
 		# The DANE TLSA record will remain valid so long as the private key
 		# hasn't changed. We don't ever change the private key automatically.
 		# If the user does it, they must manually update DNS.
+		if is_tlsa_update_required:
+			from dns_update import do_dns_update, set_custom_dns_record, build_tlsa_record
+			subprocess.check_output([
+				"mv", env["STORAGE_ROOT"] + "/ssl/next_ssl_private_key.pem",
+					  env["STORAGE_ROOT"] + "/ssl/ssl_private_key.pem"
+			])
+			subprocess.check_output([
+				"openssl", "genrsa",
+				"-out", env["STORAGE_ROOT"] + "/ssl/next_ssl_private_key.pem",
+				"2048"])
+			qname1 = "_25._tcp." + env['PRIMARY_HOSTNAME']
+			qname2 = "_443._tcp." + env['PRIMARY_HOSTNAME']
+			rtype = "TLSA"
+			value = build_tlsa_record(env, from_cert=False)
+			action = "add"
+			if set_custom_dns_record(qname1, rtype, value, action, env):
+				set_custom_dns_record(qname2, rtype, value, action, env)
+				ret.append(do_dns_update(env))
+
 
 	# Update the web configuration so nginx picks up the new certificate file.
 	from web_update import do_web_update

management/status_checks.py

@@ -454,9 +454,9 @@ def check_primary_hostname_dns(domain, env, output, dns_domains, dns_zonefiles):
 
 	# Check the TLSA record.
 	tlsa_qname = "_25._tcp." + domain
-	tlsa25 = query_dns(tlsa_qname, "TLSA", nxdomain=None)
+	tlsa25 = query_dns(tlsa_qname, "TLSA", nxdomain=None).split('; ')
 	tlsa25_expected = build_tlsa_record(env)
-	if tlsa25 == tlsa25_expected:
+	if tlsa25_expected in tlsa25:
 		output.print_ok("""The DANE TLSA record for incoming mail is correct (%s).""" % tlsa_qname,)
 	elif tlsa25 is None:
 		if has_dnssec:

management/templates/ssl.html

@@ -40,7 +40,10 @@
 
 <h3 id="ssl_install_header">Install certificate</h3>
 
-<p>If you don't want to use our automatic Let's Encrypt integration, you can give any other certificate provider a try. You can generate the needed CSR below.</p>
+<p>If you don't want to use our automatic Let's Encrypt integration, you can give any other certificate provider a try. Click on install certificate button
+    if there is no certificate for your intended domain or
+    click on renew or replace certificate button and click replace if there is an existing certificate and you want to replace it with a new one from a different CA.
+    You can generate the needed CSR below.</p>
 
 <p>Which domain are you getting a certificate for?</p>
 
@@ -101,7 +104,8 @@ function show_tls(keep_provisioning_shown) {
       $('#ssldomain').html('<option value="">(select)</option>');
       $('#ssl_domains').show();
       for (var i = 0; i < domains.length; i++) {
-        var row = $("<tr><th class='domain'><a href=''></a></th><td class='status'></td> <td class='actions'><a href='#' onclick='return ssl_install(this);' class='btn btn-xs'>Install Certificate</a></td></tr>");
+        var row = $("<tr><th class='domain'><a href=''></a></th><td class='status'></td> " +
+                "<td class='actions'><a href='#' onclick='return ssl_install(this);' class='btn btn-xs'>Install Certificate</a></td></tr>");
         tb.append(row);
         row.attr('data-domain', domains[i].domain);
         row.find('.domain a').text(domains[i].domain);
@@ -113,7 +117,10 @@ function show_tls(keep_provisioning_shown) {
         row.addClass("text-" + domains[i].status);
         row.find('.status').text(domains[i].text);
         if (domains[i].status == "success") {
-          row.find('.actions a').addClass('btn-default').text('Replace Certificate');
+          row.find('.actions a').addClass('btn-default').text('Renew or replace Certificate');
+          row.find('.actions a').addClass('btn-default').on("click", function () {
+              ssl_renew_or_replace_modal(this);
+          });
         } else {
           row.find('.actions a').addClass('btn-primary').text('Install Certificate');
         }
@@ -131,6 +138,65 @@ function ssl_install(elem) {
   return false;
 }
 
+function ssl_renew_or_replace_modal(elem) {
+    show_modal_confirm(
+    "Options",
+    "Do you want to replace the certificate with a new one or just renew this one?",
+    ["Replace", "Renew"],
+    function () {
+        ssl_install(elem);
+    },
+    function () {
+        ssl_cert_renew(elem);
+    });
+}
+function ssl_cert_renew(elem) {
+    var domain = $(elem).parents('tr').attr('data-domain');
+    show_modal_confirm(
+    "Options",
+    "Do you want to renew with the existing key?",
+    ["Yes", "No"],
+    function () {
+        ajax_with_indicator(true);
+        api(
+        "/ssl/renew/" + domain,
+        "POST",
+        {
+            existing_key: "yes"
+        },
+        function(data) {
+            $('#ajax_loading_indicator').stop(true).hide();
+          show_modal_error(data["title"], data["log"]);
+          show_tls(true);
+        },
+        function () {
+            $('#ajax_loading_indicator').stop(true).hide();
+            show_modal_error("Error", "Something is not right, sorry!");
+            show_tls(true);
+        });
+    },
+    function () {
+        ajax_with_indicator(true);
+        api(
+        "/ssl/renew/" + domain,
+        "POST",
+        {
+            existing_key: "no"
+        },
+        function(data) {
+            $('#ajax_loading_indicator').stop(true).hide();
+            show_modal_error(data["title"], data["log"]);
+            show_tls(true);
+        },
+        function () {
+            $('#ajax_loading_indicator').stop(true).hide();
+            show_modal_error("Error", "Something is not right, sorry!");
+            show_tls(true);
+        }
+        );
+    });
+}
+
 function show_csr() {
  // Can't show a CSR until both inputs are entered.
  if ($('#ssldomain').val() == "") return;

setup/ssl.sh

@@ -19,7 +19,7 @@
 #
 # The Diffie-Hellman cipher bits are used for SMTP and HTTPS, when a
 # Diffie-Hellman cipher is selected during TLS negotiation. Diffie-Hellman
-# provides Perfect Forward Secrecy. 
+# provides Perfect Forward Secrecy.
 
 source setup/functions.sh # load our functions
 source /etc/mailinabox.conf # load global vars
@@ -66,6 +66,13 @@ if [ ! -f $STORAGE_ROOT/ssl/ssl_private_key.pem ]; then
 		openssl genrsa -out $STORAGE_ROOT/ssl/ssl_private_key.pem 2048)
 fi
 
+# for Double TLSA scheme. More details here (https://mail.sys4.de/pipermail/dane-users/2018-February/000440.html)
+if [ ! -f $STORAGE_ROOT/ssl/next_ssl_private_key.pem ]; then
+	# Set the umask so the key file is never world-readable.
+	(umask 077; hide_output \
+		openssl genrsa -out $STORAGE_ROOT/ssl/next_ssl_private_key.pem 2048)
+fi
+
 # Generate a self-signed SSL certificate because things like nginx, dovecot,
 # etc. won't even start without some certificate in place, and we need nginx
 # so we can offer the user a control panel to install a better certificate.