1 files changed, 54 insertions, 1 deletions

diff --git a/src/mailman_pgp/pgp/mime.py b/src/mailman_pgp/pgp/mime.py
index a1303c9..e40f581 100644
--- a/src/mailman_pgp/pgp/mime.py
+++ b/src/mailman_pgp/pgp/mime.py
@@ -29,7 +29,7 @@ from pgpy.constants import HashAlgorithm, SymmetricKeyAlgorithm
 from public import public
 
 from mailman_pgp.utils.email import copy_headers
-from mailman_pgp.utils.pgp import key_from_blob
+from mailman_pgp.utils.pgp import key_from_blob, revoc_from_blob
 
 
 @public
@@ -208,6 +208,59 @@ class MIMEWrapper:
         out.attach(key_part)
         return out
 
+    def _is_revoc(self, part):
+        if part.get_content_type() != MIMEWrapper._keys_type:
+            return False
+        try:
+            revoc_from_blob(part.get_payload())
+        except ValueError:
+            return False
+        return True
+
+    def is_revocs(self):
+        for part in walk(self.msg):
+            if (not part.is_multipart() and not self._is_revoc(part)):
+                return False
+        return True
+
+    def has_revocs(self):
+        for part in walk(self.msg):
+            if (not part.is_multipart() and self._is_revoc(part)):
+                return True
+        return False
+
+    def revocs(self):
+        for part in walk(self.msg):
+            if (not part.is_multipart()  # noqa
+                and part.get_content_type() == MIMEWrapper._keys_type):
+                try:
+                    revoc = revoc_from_blob(part.get_payload())
+                except:
+                    continue
+                yield revoc
+
+    def attach_revoc(self, key_revocation):
+        """
+        Attach a key revocation signature to the message, as a key subpart.
+
+        :param key_revocation: A key revocation signature to attach.
+        :type key_revocation: pgpy.PGPSignature
+        :return: The message with the signature attached.
+        :rtype: mailman.email.message.Message
+        """
+        filename = '0x' + key_revocation.signer + '.asc'
+        key_part = MIMEApplication(_data=str(key_revocation),
+                                   _subtype=MIMEWrapper._keys_subtype,
+                                   _encoder=encode_7or8bit,
+                                   name=filename)
+        key_part.add_header('Content-Description',
+                            'OpenPGP key')
+        key_part.add_header('Content-Disposition', 'attachment',
+                            filename=filename)
+        out = copy.deepcopy(self.msg)
+        out.attach(key_part)
+        return out
+
     def verify(self, key):
         """
         Verify the signature of this message with key.