Setup mtail (#388)

Co-authored-by: holger krekel <holger@merlinux.eu>

chatmaild/src/chatmaild/config.py

@@ -30,6 +30,7 @@ class Config:
         self.passthrough_recipients = params["passthrough_recipients"].split()
         self.filtermail_smtp_port = int(params["filtermail_smtp_port"])
         self.postfix_reinject_port = int(params["postfix_reinject_port"])
+        self.mtail_address = params.get("mtail_address")
         self.disable_ipv6 = params.get("disable_ipv6", "false").lower() == "true"
         self.imap_rawlog = params.get("imap_rawlog", "false").lower() == "true"
         self.iroh_relay = params.get("iroh_relay")

chatmaild/src/chatmaild/filtermail.py

@@ -183,15 +183,29 @@ class BeforeQueueHandler:
         mail_encrypted = check_encrypted(message)
 
         _, from_addr = parseaddr(message.get("from").strip())
+        envelope_from_domain = from_addr.split("@").pop()
+
         logging.info(f"mime-from: {from_addr} envelope-from: {envelope.mail_from!r}")
         if envelope.mail_from.lower() != from_addr.lower():
             return f"500 Invalid FROM <{from_addr!r}> for <{envelope.mail_from!r}>"
 
+        if mail_encrypted:
+            print("Filtering encrypted mail.", file=sys.stderr)
+        else:
+            print("Filtering unencrypted mail.", file=sys.stderr)
+
         if envelope.mail_from in self.config.passthrough_senders:
             return
 
         passthrough_recipients = self.config.passthrough_recipients
-        envelope_from_domain = from_addr.split("@").pop()
+
+        is_securejoin = message.get("secure-join") in [
+            "vc-request",
+            "vg-request",
+        ]
+        if is_securejoin:
+            return
+
         for recipient in envelope.rcpt_tos:
             if envelope.mail_from == recipient:
                 # Always allow sending emails to self.
@@ -205,12 +219,8 @@ class BeforeQueueHandler:
 
             is_outgoing = recipient_domain != envelope_from_domain
             if is_outgoing and not mail_encrypted:
-                is_securejoin = message.get("secure-join") in [
-                    "vc-request",
-                    "vg-request",
-                ]
-                if not is_securejoin:
-                    return f"500 Invalid unencrypted mail to <{recipient}>"
+                print("Rejected unencrypted mail.", file=sys.stderr)
+                return f"500 Invalid unencrypted mail to <{recipient}>"
 
 
 class SendRateLimiter:

chatmaild/src/chatmaild/ini/chatmail.ini.f

@@ -55,6 +55,22 @@ postfix_reinject_port = 10025
 # if set to "True" IPv6 is disabled
 disable_ipv6 = False
 
+# Address on which `mtail` listens,
+# e.g. 127.0.0.1 or some private network
+# address like 192.168.10.1.
+# You can point Prometheus
+# or some other OpenMetrics-compatible
+# collector to
+# http://{{mtail_address}}:3903/metrics
+# and display collected metrics with Grafana.
+#
+# WARNING: do not expose this service
+# to the public IP address.
+#
+# `mtail is not running if the setting is not set.
+
+# mtail_address = 127.0.0.1
+
 #
 # Debugging options 
 #