Support for preserving original DKIM headers

2 files changed, 8 insertions, 0 deletions

diff --git a/Mailman/Defaults.py.in b/Mailman/Defaults.py.in
index 3569cc07..5dd0b30b 100755
--- a/Mailman/Defaults.py.in
+++ b/Mailman/Defaults.py.in
@@ -618,6 +618,7 @@ NNTP_REWRITE_DUPLICATE_HEADERS = [
 # No, 0, False -> do not remove headers.
 # Yes, 1, True -> remove headers only if the list's from_is_list setting is 1.
 # 2 -> always remove headers.
+# 3 -> rename and preserve original DKIM headers.
 REMOVE_DKIM_HEADERS = No
 
 # All `normal' messages which are delivered to the entire list membership go
diff --git a/Mailman/Handlers/CleanseDKIM.py b/Mailman/Handlers/CleanseDKIM.py
index 2cfb07af..bed67666 100644
--- a/Mailman/Handlers/CleanseDKIM.py
+++ b/Mailman/Handlers/CleanseDKIM.py
@@ -43,6 +43,13 @@ def process(mlist, msg, msgdata):
            )
        ):
         return
+    if (mm_cfg.REMOVE_DKIM_HEADERS == 3):
+        if 'domainkey-signature' in msg:
+            msg['X-Mailman-Original-DomainKey-Signature'] = msg['domainkey-signature']
+        if 'dkim-signature' in msg:
+            msg['X-Mailman-Original-DKIM-Signature'] = msg['dkim-signature']
+        if 'authentication-results' in msg:
+            msg['X-Mailman-Original-Authentication-Results'] = msg['authentication-results']
     del msg['domainkey-signature']
     del msg['dkim-signature']
     del msg['authentication-results']