1 files changed, 26 insertions, 5 deletions

diff --git a/src/mailman_pgp/pgp/mime.py b/src/mailman_pgp/pgp/mime.py
index 7a632bf..8b87abe 100644
--- a/src/mailman_pgp/pgp/mime.py
+++ b/src/mailman_pgp/pgp/mime.py
@@ -19,8 +19,13 @@
 from email.message import Message
 from email.utils import collapse_rfc2231_value
 
+from pgpy import PGPKey, PGPSignature
+
 
 class PGPMIMEWrapper:
+    _signed_subtype = 'application/pgp-signature'
+    _encrypted_subtype = 'application/pgp-encrypted'
+
     def __init__(self, msg: Message):
         self.msg = msg
 
@@ -41,9 +46,9 @@ class PGPMIMEWrapper:
         protocol_param = collapse_rfc2231_value(self.msg.get_param('protocol'))
         content_subtype = self.msg.get_content_subtype()
 
-        return second_type == 'application/pgp-signature' and \
-            content_subtype == 'signed' and \
-            protocol_param == 'application/pgp-signature'
+        return second_type == PGPMIMEWrapper._signed_subtype and \
+               content_subtype == 'signed' and \
+               protocol_param == PGPMIMEWrapper._signed_subtype
 
     def is_mime_encrypted(self):
         """
@@ -59,7 +64,23 @@ class PGPMIMEWrapper:
         protocol_param = collapse_rfc2231_value(self.msg.get_param('protocol'))
 
         return 'Version: 1' in first_part and \
-               first_type == 'application/pgp-encrypted' and \
+               first_type == PGPMIMEWrapper._encrypted_subtype and \
                second_type == 'application/octet-stream' and \
                content_subtype == 'encrypted' and \
-               protocol_param == 'application/pgp-encrypted'
+               protocol_param == PGPMIMEWrapper._encrypted_subtype
+
+    def verify(self, key: PGPKey):
+        """
+
+        :param key:
+        :return:
+        """
+        clear_text = str(self.msg.get_payload(0))
+        sig_text = self.msg.get_payload(1).get_payload()
+        signature = PGPSignature.from_blob(sig_text)
+        verification = key.verify(clear_text,
+                                  signature)
+        return signature in [v.signature for v in verification.good_signatures]
+
+    def decrypt(self, key: PGPKey):
+        pass