From 3b6cebb79cab195438e5c3620796aca547fca40f Mon Sep 17 00:00:00 2001
From: Thomas Oettli <spacefreak@noop.ch>
Date: Fri, 28 Feb 2020 19:28:20 +0100
Subject: [PATCH] Replace 0-bytes and line breaks, pymilter does not like them

---
 pyheadermilter/__init__.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/pyheadermilter/__init__.py b/pyheadermilter/__init__.py
index f102e6a..56ac12d 100644
--- a/pyheadermilter/__init__.py
+++ b/pyheadermilter/__init__.py
@@ -210,7 +210,8 @@ class HeaderMilter(Milter.Base):
 
                 for name, hdr, index, occurrence in modified:
                     value = hdr[name]
-                    encoded_value = hdr.as_string().split(": ")[1].rstrip()
+                    # remove illegal characters, pymilter does not like them
+                    encoded_value = hdr.as_string().replace("\r", "").replace("\n", "").replace("\x00", "").split(":", 1)[1].strip()
                     mod_header = "{}: {}".format(name, value)
                     if rule.action == "add":
                         if rule.log: