Revert "Revert "Aggressive LMTP header cleanup (#816)""

This reverts commit 6def189d16.

cmdeploy/src/cmdeploy/acmetool/response-file.yaml.j2

@@ -1,2 +1,2 @@
 "acme-enter-email": "{{ email }}"
-"acme-agreement:https://letsencrypt.org/documents/LE-SA-v1.7-June-04-2026.pdf": true
+"acme-agreement:https://letsencrypt.org/documents/LE-SA-v1.6-August-18-2025.pdf": true

cmdeploy/src/cmdeploy/basedeploy.py

@@ -166,7 +166,7 @@ class Deployer:
             return self.put_template(src, dest, **kwargs)
         return self.put_file(src, dest)
 
-    def put_file(self, src, dest, mode="644", **kwargs):
+    def put_file(self, src, dest, mode="644"):
         if isinstance(src, str):
             src = get_resource(src)
         res = files.put(
@@ -176,7 +176,6 @@ class Deployer:
             user="root",
             group="root",
             mode=mode,
-            **kwargs,
         )
 
         return self._update_restart_signals(dest, res)

cmdeploy/src/cmdeploy/deployers.py

@@ -164,7 +164,6 @@ class UnboundDeployer(Deployer):
         self.put_file(
             src=BytesIO(b"nameserver 127.0.0.1\nnameserver 9.9.9.9\n"),
             dest="/etc/resolv.conf",
-            force=True,
         )
         server.shell(
             name="Generate root keys for validating DNSSEC",

cmdeploy/src/cmdeploy/postfix/lmtp_header_cleanup

@@ -1,3 +1,23 @@
-/^DKIM-Signature:/            IGNORE
-/^Authentication-Results:/            IGNORE
-/^Received:/            IGNORE
+# List of headers for incoming messages 
+# that must be retained for functionality and compatibility reasons 
+/^From:/            DUNNO
+/^Message-Id:/      DUNNO
+/^Chat-/            DUNNO
+/^Content-Type:/    DUNNO
+
+# For receiving clear-text messages (still supported in May 2026)
+/^Subject:/         DUNNO
+/^Date:/            DUNNO
+/^To:/              DUNNO
+/^CC:/              DUNNO
+/^References:/      DUNNO
+/^In-Reply-To:/     DUNNO
+
+# Senders might support Autocrypt 1 but not RFC9788 (Header Protection) 
+/^Autocrypt:/       DUNNO
+
+# SecureJoin V2 protocol headers (for backward compatibility) 
+/^Secure-Join/      DUNNO
+
+# Ignore all other headers
+/.*/                IGNORE