remove surrogates from headers again, the cause troubles

README.md

@@ -8,6 +8,7 @@ The basic idea is to define rules with conditions and actions which are processe
 Pymodmilter is depending on these python packages, but they are installed automatically if you are working with pip.
 * [pymilter](https://pythonhosted.org/pymilter/)
 * [netaddr](https://github.com/drkjam/netaddr/)
+* [BeautifulSoup](https://www.crummy.com/software/BeautifulSoup/)
 
 ## Installation
 * Install pymodmilter with pip and copy the example config file.

pymodmilter/__init__.py

@@ -21,7 +21,7 @@ __all__ = [
     "ModifyMilterConfig",
     "ModifyMilter"]
 
-__version__ = "1.1.4"
+__version__ = "1.1.6"
 
 from pymodmilter import _runtime_patches
 

pymodmilter/base.py

@@ -136,8 +136,5 @@ class MilterMessage(MIMEPart):
 
 
 def replace_illegal_chars(string):
-    """Replace illegal characters in header values."""
-    return string.replace(
-        "\x00", "").replace(
-        "\r", "").replace(
-        "\n", "")
+    """Remove illegal characters from header values."""
+    return "".join(string.replace("\x00", "").splitlines())

setup.py

@@ -46,6 +46,6 @@ setup(name = "pymodmilter",
             ]
         )
     ],
-    install_requires = ["pymilter", "netaddr"],
+    install_requires = ["pymilter", "netaddr", "beautifulsoup4[lxml]"],
     python_requires = ">=3.6"
 )