Add conflict resolution for multiple users using the same key. Fixes #1.

multischleuder/conflict.py

@@ -16,16 +16,17 @@ from datetime import datetime
 
 import pgpy  # type: ignore
 
-from multischleuder.reporting import ConflictMessage, Message
+from multischleuder.reporting import KeyConflictMessage, Message, UserConflictMessage
 from multischleuder.types import SchleuderKey, SchleuderSubscriber
 
 
 class KeyConflictResolution:
 
-    def __init__(self, interval: int, statefile: str, template: str):
+    def __init__(self, interval: int, statefile: str, key_template: str, user_template: str):
         self._interval: int = interval
         self._state_file: str = statefile
-        self._template: str = template
+        self._key_template: str = key_template
+        self._user_template: str = user_template
         self._dry_run: bool = False
         self._logger: logging.Logger = logging.getLogger()
 
@@ -36,25 +37,41 @@ class KeyConflictResolution:
                 target: str,
                 mail_from: str,
                 subscriptions: List[SchleuderSubscriber]) -> Tuple[List[SchleuderSubscriber], List[Optional[Message]]]:
-        subs: Dict[str, List[SchleuderSubscriber]] = OrderedDict()
+        conflicts: List[Optional[Message]] = []
+
+        # First check for keys that are being used by more than one subscriber
+        keys: Dict[str, List[SchleuderSubscriber]] = {}
         for s in subscriptions:
+            if s.key is None:
+                continue
+            keys.setdefault(s.key.fingerprint, []).append(s)
+        key_resolved: List[SchleuderSubscriber] = []
+        for k in keys.values():
+            rk, m = self._resolve_users(target, mail_from, k)
+            if rk is not None:
+                key_resolved.append(rk)
+            if m is not None:
+                conflicts.extend(m)
+
+        subs: Dict[str, List[SchleuderSubscriber]] = OrderedDict()
+        # Only consider subscribers who have not been removed due to a key used by multiple users
+        for s in key_resolved:
             subs.setdefault(s.email, []).append(s)
         # Perform conflict resolution for each set of subscribers with the same email
         resolved: List[SchleuderSubscriber] = []
-        conflicts: List[Optional[Message]] = []
         for c in subs.values():
-            r, m = self._resolve(target, mail_from, c)
+            r, msg = self._resolve_keys(target, mail_from, c)
             if r is not None:
                 resolved.append(r)
-            if m is not None:
+            if msg is not None:
-                conflicts.append(m)
+                conflicts.append(msg)
         return resolved, conflicts
 
-    def _resolve(self,
+    def _resolve_keys(self,
-                 target: str,
+                      target: str,
-                 mail_from: str,
+                      mail_from: str,
-                 subscriptions: List[SchleuderSubscriber]) \
+                      subscriptions: List[SchleuderSubscriber]) \
-            -> Tuple[Optional[SchleuderSubscriber], Optional[ConflictMessage]]:
+            -> Tuple[Optional[SchleuderSubscriber], Optional[Message]]:
         notnull = [s for s in subscriptions if s.key is not None]
         if len(notnull) == 0:
             return None, None
@@ -69,21 +86,58 @@ class KeyConflictResolution:
             fpr = 'no key' if s.key is None else s.key.fingerprint
             self._logger.debug(f'  - {s.schleuder}: {fpr}')
         # Generate a SHA1 digest that only changes when the subscription list changes
-        digest = self._make_digest(earliest, subscriptions)
+        digest = self._make_key_digest(earliest, subscriptions)
-        msg: Optional[ConflictMessage] = None
+        msg: Optional[Message] = None
         # Create a conflict message only if it hasn't been sent recently
         if self._should_send(digest):
-            msg = ConflictMessage(
+            msg = KeyConflictMessage(
                 target,
                 earliest,
                 subscriptions,
                 digest,
                 mail_from,
-                self._template
+                self._key_template
             )
         # Return the result of conflict resolution
         return earliest, msg
 
+    def _resolve_users(self,
+                       target: str,
+                       mail_from: str,
+                       subscriptions: List[SchleuderSubscriber]) \
+            -> Tuple[Optional[SchleuderSubscriber], Optional[List[Message]]]:
+        notnull = [s for s in subscriptions if s.key is not None]
+        if len(notnull) == 0:
+            return None, None
+        emails = {s.email for s in notnull}
+        if len(emails) == 1:
+            # No conflict if all emails are the same
+            return notnull[0], None
+        # Conflict Resolution: Choose the OLDEST subscription with a key, but notify using ALL recipients
+        earliest: SchleuderSubscriber = min(notnull, key=lambda x: x.created_at)
+        assert earliest.key is not None  # Make mypy happy; it can't know that earliest.key can't be None
+        self._logger.debug(f'User Conflict for {earliest.key.fingerprint} in lists, chose {earliest.email}:')
+        for s in subscriptions:
+            self._logger.debug(f'  - {s.schleuder}: {s.email}')
+        # Generate a SHA1 digest that only changes when the subscription list changes
+        digest = self._make_user_digest(earliest, subscriptions)
+        msgs: Optional[List[Message]] = None
+        # Create a conflict message only if it hasn't been sent recently
+        if self._should_send(digest):
+            msgs = []
+            for email in emails:
+                msgs.append(UserConflictMessage(
+                    target,
+                    email,
+                    earliest,
+                    subscriptions,
+                    digest,
+                    mail_from,
+                    self._user_template
+                ))
+        # Return the result of conflict resolution
+        return earliest, msgs
+
     def _should_send(self, digest: str) -> bool:
         now = int(datetime.utcnow().timestamp())
         try:
@@ -114,7 +168,7 @@ class KeyConflictResolution:
             self._logger.exception('Cannot open or write statefile.  Not sending any messages!')
         return False
 
-    def _make_digest(self, chosen: SchleuderSubscriber, candidates: List[SchleuderSubscriber]) -> str:
+    def _make_key_digest(self, chosen: SchleuderSubscriber, candidates: List[SchleuderSubscriber]) -> str:
         # Sort so the hash stays the same if the set of subscriptions is the same.
         # There is no guarantee that the subs are in any specific order.
         subs: List[SchleuderSubscriber] = sorted(candidates, key=lambda x: x.schleuder)
@@ -130,3 +184,19 @@ class KeyConflictResolution:
                 key = s.key.blob.encode()
             h.update(struct.pack('!ds', s.schleuder, key))
         return h.hexdigest()
+
+    def _make_user_digest(self, chosen: SchleuderSubscriber, candidates: List[SchleuderSubscriber]) -> str:
+        # Sort so the hash stays the same if the set of subscriptions is the same.
+        # There is no guarantee that the subs are in any specific order.
+        subs: List[SchleuderSubscriber] = sorted(candidates, key=lambda x: x.schleuder)
+        h = hashlib.new('sha1')
+        assert chosen.key is not None  # Make mypy happy; it can't know that chosen.key can't be None
+        # Include the chosen email an source sub-list
+        h.update(struct.pack('!ssd',
+                             chosen.key.fingerprint.encode(),
+                             chosen.email.encode(),
+                             chosen.schleuder))
+        # Include all subscriptions, including the FULL key
+        for s in subs:
+            h.update(struct.pack('!ds', s.schleuder, s.email.encode()))
+        return h.hexdigest()

multischleuder/reporting.py

@@ -83,7 +83,7 @@ class Message(abc.ABC):
         return mp0
 
 
-class ConflictMessage(Message):
+class KeyConflictMessage(Message):
 
     def __init__(self,
                  schleuder: str,
@@ -119,6 +119,43 @@ class ConflictMessage(Message):
         self.mime['X-MultiSchleuder-Digest'] = digest
 
 
+class UserConflictMessage(Message):
+
+    def __init__(self,
+                 schleuder: str,
+                 subscriber: str,
+                 chosen: SchleuderSubscriber,
+                 affected: List[SchleuderSubscriber],
+                 digest: str,
+                 mail_from: str,
+                 template: str):
+        # Render the message body
+        assert chosen.key is not None
+        _chosen = chosen.email
+        _affected = ''
+        for a in affected:
+            _affected += f'{a.email}  {a.schleuder}\n'
+        content = template.format(
+            subscriber=subscriber,
+            fingerprint=chosen.key.fingerprint,
+            schleuder=schleuder,
+            chosen=_chosen,
+            affected=_affected
+        )
+        self._chosen: SchleuderSubscriber = chosen
+        self._affected: List[SchleuderSubscriber] = affected
+        self._template: str = template
+        super().__init__(
+            schleuder=schleuder,
+            mail_from=mail_from,
+            mail_to=chosen.email,
+            content=content,
+            encrypt_to=[chosen.key.blob]
+        )
+        self.mime['Subject'] = f'MultiSchleuder {self._schleuder} - Subscriber Conflict'
+        self.mime['X-MultiSchleuder-Digest'] = digest
+
+
 class AdminReport(Message):
 
     def __init__(self,
@@ -194,7 +231,9 @@ class Reporter:
     def add_message(self, message: Optional[Message]):
         if message is None:
             return
-        if not self._send_conflict_messages and isinstance(message, ConflictMessage):
+        if not self._send_conflict_messages and isinstance(message, KeyConflictMessage):
+            return
+        if not self._send_conflict_messages and isinstance(message, UserConflictMessage):
             return
         if not self._send_admin_reports and isinstance(message, AdminReport):
             return

multischleuder/test/test_config.py

@@ -13,7 +13,8 @@ api:
 conflict:
   interval: 3600
   statefile: /tmp/state.json
-  template: ''
+  key_template: ''
+  user_template: ''
 '''
 
 
@@ -34,13 +35,20 @@ smtp:
 conflict:
   interval: 3600
   statefile: /tmp/state.json
-  template: |
+  key_template: |
     Dear {subscriber}
     This is a test and should not be used in production:
     {affected}
     If you ever receive this text via email, notify your admin:
     {chosen}
     Regards, {schleuder}
+  user_template: |
+    Dear {subscriber}
+    This is a test and should not be used in production:
+    {affected}
+    If you ever receive this text via email, notify your admin:
+    {chosen}
+    Kind regards, {schleuder}
 
 lists:
 
@@ -97,7 +105,8 @@ class TestConfig(unittest.TestCase):
         self.assertEqual(False, list1._api._dry_run)
         self.assertEqual(3600, list2._kcr._interval)
         self.assertEqual('/tmp/state.json', list1._kcr._state_file)
-        self.assertIn('Regards, {schleuder}', list2._kcr._template)
+        self.assertIn('Regards, {schleuder}', list2._kcr._key_template)
+        self.assertIn('Kind regards, {schleuder}', list2._kcr._user_template)
 
         self.assertEqual('test-global@schleuder.example.org', list1._target)
         self.assertEqual('test-global-owner@schleuder.example.org', list1._mail_from)

multischleuder/test/test_conflict.py

@@ -8,7 +8,8 @@ from unittest.mock import patch, mock_open, MagicMock
 import pgpy  # type: ignore
 from dateutil.tz import tzutc
 
-from multischleuder.conflict import ConflictMessage, KeyConflictResolution
+from multischleuder.conflict import KeyConflictResolution
+from multischleuder.reporting import UserConflictMessage
 from multischleuder.types import SchleuderKey, SchleuderList, SchleuderSubscriber
 
 
@@ -52,7 +53,13 @@ QBzu2Swgk6MkU45SLQD+LagpBVJxHcbvmK+n8MFvTSrusF8H78P4TrMLP4Onvw4=
 ''')
 
 
-_TEMPLATE = '''{{
+_KEY_TEMPLATE = '''{{
+  "subscriber": "{subscriber}",
+  "schleuder": "{schleuder}",
+  "chosen": "{chosen}"
+}}'''
+_USER_TEMPLATE = '''{{
+  "fingerprint": "{fingerprint}",
   "subscriber": "{subscriber}",
   "schleuder": "{schleuder}",
   "chosen": "{chosen}"
@@ -70,7 +77,7 @@ _CONFLICT_STATE_RECENT = f'''{{
 
 class TestKeyConflictResolution(unittest.TestCase):
 
-    def test_order_resistent_hash(self):
+    def test_order_resistent_key_hash(self):
         sch1 = SchleuderList(42, 'test-north@schleuder.example.org', '474777DA74528A7021184C8A0017324A6CFFBF92')
         key1 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_1.pubkey), sch1.id)
         date1 = datetime(2022, 4, 15, 5, 23, 42, 0, tzinfo=tzutc())
@@ -79,19 +86,39 @@ class TestKeyConflictResolution(unittest.TestCase):
         key2 = SchleuderKey(_PRIVKEY_2.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_2.pubkey), sch2.id)
         date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
 
-        digest1 = kcr._make_digest(sub2, [sub1, sub2])
+        digest1 = kcr._make_key_digest(sub2, [sub1, sub2])
-        digest2 = kcr._make_digest(sub2, [sub2, sub1])
+        digest2 = kcr._make_key_digest(sub2, [sub2, sub1])
-        digest3 = kcr._make_digest(sub1, [sub1, sub2])
+        digest3 = kcr._make_key_digest(sub1, [sub1, sub2])
-        digest4 = kcr._make_digest(sub1, [sub2, sub1])
+        digest4 = kcr._make_key_digest(sub1, [sub2, sub1])
+
+        self.assertEqual(digest1, digest2)
+        self.assertNotEqual(digest1, digest3)
+        self.assertEqual(digest3, digest4)
+
+    def test_order_resistent_user_hash(self):
+        sch1 = SchleuderList(42, 'test-north@schleuder.example.org', '474777DA74528A7021184C8A0017324A6CFFBF92')
+        key1 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_1.pubkey), sch1.id)
+        date1 = datetime(2022, 4, 15, 5, 23, 42, 0, tzinfo=tzutc())
+        sub1 = SchleuderSubscriber(3, 'foo@example.org', key1, sch1.id, date1)
+        sch2 = SchleuderList(23, 'test-south@schleuder.example.org', 'AF586C0625CF77BBB659747515D41C5D84BF99D3')
+        key2 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'bar@example.org', str(_PRIVKEY_1.pubkey), sch2.id)
+        date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
+        sub2 = SchleuderSubscriber(7, 'bar@example.org', key2, sch2.id, date2)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
+
+        digest1 = kcr._make_user_digest(sub2, [sub1, sub2])
+        digest2 = kcr._make_user_digest(sub2, [sub2, sub1])
+        digest3 = kcr._make_user_digest(sub1, [sub1, sub2])
+        digest4 = kcr._make_user_digest(sub1, [sub2, sub1])
 
         self.assertEqual(digest1, digest2)
         self.assertNotEqual(digest1, digest3)
         self.assertEqual(digest3, digest4)
 
     def test_empty(self):
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO(_CONFLICT_STATE_NONE)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_NONE)) as mock_statefile:
@@ -105,7 +132,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         key1 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_1.pubkey), sch1.id)
         date1 = datetime(2022, 4, 15, 5, 23, 42, 0, tzinfo=tzutc())
         sub1 = SchleuderSubscriber(3, 'foo@example.org', key1, sch1.id, date1)
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         resolved, messages = kcr.resolve('', '', [sub1])
         self.assertEqual(1, len(resolved))
         self.assertEqual(sub1, resolved[0])
@@ -123,7 +150,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO(_CONFLICT_STATE_NONE)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_NONE)) as mock_statefile:
@@ -150,7 +177,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO(_CONFLICT_STATE_NONE)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_NONE)) as mock_statefile:
@@ -187,7 +214,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
         sub2 = SchleuderSubscriber(7, 'foo@example.org', None, sch2.id, date2)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO(_CONFLICT_STATE_NONE)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_NONE)) as mock_statefile:
@@ -207,7 +234,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         date1 = datetime(2022, 4, 15, 5, 23, 42, 0, tzinfo=tzutc())
         sub1 = SchleuderSubscriber(3, 'foo@example.org', None, sch1.id, date1)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO(_CONFLICT_STATE_NONE)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_NONE)) as mock_statefile:
@@ -219,6 +246,114 @@ class TestKeyConflictResolution(unittest.TestCase):
         self.assertEqual(0, len(resolved))
         self.assertEqual(0, len(messages))
 
+    def test_different_emails_conflict(self):
+        sch1 = SchleuderList(42, 'test-north@schleuder.example.org', '474777DA74528A7021184C8A0017324A6CFFBF92')
+        key1 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_1.pubkey), sch1.id)
+        date1 = datetime(2022, 4, 15, 5, 23, 42, 0, tzinfo=tzutc())
+        sub1 = SchleuderSubscriber(3, 'foo@example.org', key1, sch1.id, date1)
+
+        # This subscription is older, so it will be preferred
+        sch2 = SchleuderList(23, 'test-south@schleuder.example.org', 'AF586C0625CF77BBB659747515D41C5D84BF99D3')
+        key2 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'bar@example.org', str(_PRIVKEY_1.pubkey), sch2.id)
+        date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
+        sub2 = SchleuderSubscriber(7, 'bar@example.org', key2, sch2.id, date2)
+
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
+        contents = io.StringIO(_CONFLICT_STATE_NONE)
+        contents.seek(io.SEEK_END)  # Opened with 'a+'
+        with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_NONE)) as mock_statefile:
+            mock_statefile().__enter__.return_value = contents
+            resolved, messages = kcr.resolve(
+                target='test@schleuder.example.org',
+                mail_from='test-owner@schleuder.example.org',
+                subscriptions=[sub1, sub2])
+
+        self.assertEqual(1, len(resolved))
+        self.assertEqual('bar@example.org', resolved[0].email)
+        # Different emails should trigger conflict messages
+        self.assertEqual(2, len(messages))
+        self.assertIsInstance(messages[0], UserConflictMessage)
+        self.assertIsInstance(messages[1], UserConflictMessage)
+        msg1 = messages[0].mime
+        pgp1 = pgpy.PGPMessage.from_blob(msg1.get_payload()[1].get_payload(decode=True))
+        msg2 = messages[1].mime
+        pgp2 = pgpy.PGPMessage.from_blob(msg2.get_payload()[1].get_payload(decode=True))
+        # Verify that the message is encrypted
+        dec1 = _PRIVKEY_1.decrypt(pgp1)
+        dec2 = _PRIVKEY_1.decrypt(pgp2)
+        self.assertNotEqual(dec1.message, dec2.message)
+
+        payload1 = json.loads(dec1.message)
+        payload2 = json.loads(dec2.message)
+        if payload1['subscriber'] != 'foo@example.org':
+            payload1, payload2 = payload2, payload1
+        self.assertEqual('foo@example.org', payload1['subscriber'])
+        self.assertEqual('2FBBC0DF97FDBF1E4B704EEDE39EF4FAC420BEB6', payload1['fingerprint'])
+        self.assertEqual('test@schleuder.example.org', payload1['schleuder'])
+        self.assertEqual('bar@example.org', payload1['chosen'])
+        self.assertEqual('bar@example.org', payload2['subscriber'])
+        self.assertEqual('2FBBC0DF97FDBF1E4B704EEDE39EF4FAC420BEB6', payload2['fingerprint'])
+        self.assertEqual('test@schleuder.example.org', payload2['schleuder'])
+        self.assertEqual('bar@example.org', payload2['chosen'])
+
+    def test_zigzag_conflict(self):
+        date1 = datetime(2022, 4, 15, 5, 23, 42, 0, tzinfo=tzutc())
+        date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
+
+        sch1 = SchleuderList(42, 'test-north@schleuder.example.org', '474777DA74528A7021184C8A0017324A6CFFBF92')
+        key1 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_1.pubkey), sch1.id)
+        key2 = SchleuderKey(_PRIVKEY_2.fingerprint.replace(' ', ''), 'bar@example.org', str(_PRIVKEY_2.pubkey), sch1.id)
+        sub1 = SchleuderSubscriber(1, 'foo@example.org', key1, sch1.id, date2)
+        sub2 = SchleuderSubscriber(2, 'bar@example.org', key2, sch1.id, date2)
+
+        sch2 = SchleuderList(23, 'test-south@schleuder.example.org', 'AF586C0625CF77BBB659747515D41C5D84BF99D3')
+        key3 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'bar@example.org', str(_PRIVKEY_1.pubkey), sch2.id)
+        sub3 = SchleuderSubscriber(7, 'bar@example.org', key3, sch2.id, date1)
+
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
+        contents = io.StringIO(_CONFLICT_STATE_NONE)
+        contents.seek(io.SEEK_END)  # Opened with 'a+'
+        with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_NONE)) as mock_statefile:
+            mock_statefile().__enter__.return_value = contents
+            resolved, messages = kcr.resolve(
+                target='test@schleuder.example.org',
+                mail_from='test-owner@schleuder.example.org',
+                subscriptions=[sub1, sub2, sub3])
+
+        self.assertEqual(2, len(resolved))
+        foo, bar = resolved
+        if foo.email != 'foo@example.org':
+            foo, bar = bar, foo
+        self.assertEqual('foo@example.org', foo.email)
+        self.assertEqual('2FBBC0DF97FDBF1E4B704EEDE39EF4FAC420BEB6', foo.key.fingerprint)
+        self.assertEqual('bar@example.org', bar.email)
+        self.assertEqual('135AFA0FB3FF584828911208B7913308392972A4', bar.key.fingerprint)
+        # Different emails should trigger conflict messages
+        self.assertEqual(2, len(messages))
+        self.assertIsInstance(messages[0], UserConflictMessage)
+        self.assertIsInstance(messages[1], UserConflictMessage)
+        msg1 = messages[0].mime
+        pgp1 = pgpy.PGPMessage.from_blob(msg1.get_payload()[1].get_payload(decode=True))
+        msg2 = messages[1].mime
+        pgp2 = pgpy.PGPMessage.from_blob(msg2.get_payload()[1].get_payload(decode=True))
+        # Verify that the message is encrypted
+        dec1 = _PRIVKEY_1.decrypt(pgp1)
+        dec2 = _PRIVKEY_1.decrypt(pgp2)
+        self.assertNotEqual(dec1.message, dec2.message)
+
+        payload1 = json.loads(dec1.message)
+        payload2 = json.loads(dec2.message)
+        if payload1['subscriber'] != 'foo@example.org':
+            payload1, payload2 = payload2, payload1
+        self.assertEqual('foo@example.org', payload1['subscriber'])
+        self.assertEqual('2FBBC0DF97FDBF1E4B704EEDE39EF4FAC420BEB6', payload1['fingerprint'])
+        self.assertEqual('test@schleuder.example.org', payload1['schleuder'])
+        self.assertEqual('foo@example.org', payload1['chosen'])
+        self.assertEqual('bar@example.org', payload2['subscriber'])
+        self.assertEqual('2FBBC0DF97FDBF1E4B704EEDE39EF4FAC420BEB6', payload2['fingerprint'])
+        self.assertEqual('test@schleuder.example.org', payload2['schleuder'])
+        self.assertEqual('foo@example.org', payload2['chosen'])
+
     def test_send_messages_nofile(self):
         sch1 = SchleuderList(42, 'test-north@schleuder.example.org', '474777DA74528A7021184C8A0017324A6CFFBF92')
         key1 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_1.pubkey), sch1.id)
@@ -230,7 +365,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         key2 = SchleuderKey(_PRIVKEY_2.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_2.pubkey), sch2.id)
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
 
-        kcr = KeyConflictResolution(3600, '/nonexistent/directory/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/nonexistent/directory/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         resolved, msgs = kcr.resolve(
             target='test@schleuder.example.org',
             mail_from='test-owner@schleuder.example.org',
@@ -248,7 +383,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         key2 = SchleuderKey(_PRIVKEY_2.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_2.pubkey), sch2.id)
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO('[[intentionally/broken\\json]]')
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data='[[intentionally/broken\\json]]')) as mock_statefile:
@@ -270,7 +405,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         key2 = SchleuderKey(_PRIVKEY_2.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_2.pubkey), sch2.id)
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO()
         with patch('builtins.open', mock_open(read_data='')) as mock_statefile:
             mock_statefile().__enter__.return_value = contents
@@ -299,7 +434,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         key2 = SchleuderKey(_PRIVKEY_2.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_2.pubkey), sch2.id)
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO(_CONFLICT_STATE_NONE)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_NONE)) as mock_statefile:
@@ -318,12 +453,6 @@ class TestKeyConflictResolution(unittest.TestCase):
         self.assertIn(msgs[0].mime['X-MultiSchleuder-Digest'], state)
         self.assertLess(now - state[msgs[0].mime['X-MultiSchleuder-Digest']], 60)
 
-        # Todo: move this over to test_multilist
-        # mock_smtp = MagicMock()
-        # mock_smtp.__enter__.return_value = mock_smtp
-        # mock_smtp.__enter__.assert_called_once()
-        # self.assertEqual(2, mock_smtp.send_message.call_count)
-
     def test_send_messages_stalestate(self):
         sch1 = SchleuderList(42, 'test-north@schleuder.example.org', '474777DA74528A7021184C8A0017324A6CFFBF92')
         key1 = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_1.pubkey), sch1.id)
@@ -335,7 +464,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO(_CONFLICT_STATE_STALE)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_STALE)) as mock_statefile:
@@ -366,7 +495,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
 
-        kcr = KeyConflictResolution(86400, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(86400, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO(_CONFLICT_STATE_RECENT)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_RECENT)) as mock_statefile:
@@ -398,7 +527,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         date2 = datetime(2022, 4, 13, 5, 23, 42, 0, tzinfo=tzutc())
         sub2 = SchleuderSubscriber(7, 'foo@example.org', key2, sch2.id, date2)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         kcr.dry_run()
         contents = io.StringIO(_CONFLICT_STATE_STALE)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
@@ -431,7 +560,7 @@ class TestKeyConflictResolution(unittest.TestCase):
         date3 = datetime(2022, 4, 11, 5, 23, 42, 0, tzinfo=tzutc())
         sub3 = SchleuderSubscriber(7, 'foo@example.org', None, sch3.id, date3)
 
-        kcr = KeyConflictResolution(3600, '/tmp/state.json', _TEMPLATE)
+        kcr = KeyConflictResolution(3600, '/tmp/state.json', _KEY_TEMPLATE, _USER_TEMPLATE)
         contents = io.StringIO(_CONFLICT_STATE_NONE)
         contents.seek(io.SEEK_END)  # Opened with 'a+'
         with patch('builtins.open', mock_open(read_data=_CONFLICT_STATE_NONE)) as mock_statefile:

multischleuder/test/test_multilist.py

@@ -8,13 +8,13 @@ from unittest.mock import MagicMock
 from dateutil.tz import tzutc
 
 from multischleuder.processor import MultiList
-from multischleuder.reporting import ConflictMessage
+from multischleuder.reporting import Message
 from multischleuder.types import SchleuderKey, SchleuderList, SchleuderSubscriber
 
 
 def _resolve(target: str,
              mail_from: str,
-             subscriptions: List[SchleuderSubscriber]) -> Tuple[List[SchleuderSubscriber], List[ConflictMessage]]:
+             subscriptions: List[SchleuderSubscriber]) -> Tuple[List[SchleuderSubscriber], List[Message]]:
     # Mock conflict resolution that does not send or prepare messages
     subs: Dict[str, List[SchleuderSubscriber]] = {}
     for s in subscriptions:

multischleuder/test/test_reporting.py

@@ -3,13 +3,16 @@ import unittest
 
 from datetime import datetime
 
-from multischleuder.reporting import ConflictMessage, AdminReport, Reporter
+from multischleuder.reporting import KeyConflictMessage, AdminReport, Reporter, UserConflictMessage
 from multischleuder.types import SchleuderKey, SchleuderList, SchleuderSubscriber
+from multischleuder.test.test_conflict import _PRIVKEY_1
 
 
 def one_of_each_kind():
     sub = SchleuderSubscriber(1, 'foo@example.org', None, 1, datetime.utcnow())
-    msg1 = ConflictMessage(
+    key = SchleuderKey(_PRIVKEY_1.fingerprint.replace(' ', ''), 'foo@example.org', str(_PRIVKEY_1.pubkey), 1)
+    sub2 = SchleuderSubscriber(2, 'bar@example.org', key, 1, datetime.utcnow())
+    msg1 = KeyConflictMessage(
         schleuder='test@example.org',
         chosen=sub,
         affected=[sub],
@@ -26,7 +29,15 @@ def one_of_each_kind():
         updated={},
         added={},
         removed={})
-    return [msg1, msg2]
+    msg3 = UserConflictMessage(
+        schleuder='test@example.org',
+        subscriber='bar@example.org',
+        chosen=sub2,
+        affected=[sub2],
+        digest='digest',
+        mail_from='test-owner@example.org',
+        template='averylongmessage')
+    return [msg1, msg2, msg3]
 
 
 class TestReporting(unittest.TestCase):
@@ -36,11 +47,13 @@ class TestReporting(unittest.TestCase):
         r = Reporter(send_conflict_messages=True,
                      send_admin_reports=True)
         r.add_messages(msgs)
-        self.assertEquals(2, len(Reporter.get_messages()))
+        self.assertEqual(3, len(Reporter.get_messages()))
-        self.assertIsInstance(Reporter.get_messages()[-2], ConflictMessage)
+        self.assertIsInstance(Reporter.get_messages()[0], KeyConflictMessage)
-        self.assertEquals('foo@example.org', Reporter.get_messages()[-2]._to)
+        self.assertEqual('foo@example.org', Reporter.get_messages()[0]._to)
-        self.assertIsInstance(Reporter.get_messages()[-1], AdminReport)
+        self.assertIsInstance(Reporter.get_messages()[1], AdminReport)
-        self.assertEquals('admin@example.org', Reporter.get_messages()[-1]._to)
+        self.assertEqual('admin@example.org', Reporter.get_messages()[1]._to)
+        self.assertIsInstance(Reporter.get_messages()[2], UserConflictMessage)
+        self.assertEqual('bar@example.org', Reporter.get_messages()[2]._to)
         Reporter.clear_messages()
 
     def test_reporter_config_conflict_only(self):
@@ -48,9 +61,11 @@ class TestReporting(unittest.TestCase):
         r = Reporter(send_conflict_messages=True,
                      send_admin_reports=False)
         r.add_messages(msgs)
-        self.assertEquals(1, len(Reporter.get_messages()))
+        self.assertEqual(2, len(Reporter.get_messages()))
-        self.assertIsInstance(Reporter.get_messages()[-1], ConflictMessage)
+        self.assertIsInstance(Reporter.get_messages()[0], KeyConflictMessage)
-        self.assertEquals('foo@example.org', Reporter.get_messages()[-1]._to)
+        self.assertEqual('foo@example.org', Reporter.get_messages()[0]._to)
+        self.assertIsInstance(Reporter.get_messages()[1], UserConflictMessage)
+        self.assertEqual('bar@example.org', Reporter.get_messages()[1]._to)
         Reporter.clear_messages()
 
     def test_reporter_config_admin_only(self):
@@ -58,9 +73,9 @@ class TestReporting(unittest.TestCase):
         r = Reporter(send_conflict_messages=False,
                      send_admin_reports=True)
         r.add_messages(msgs)
-        self.assertEquals(1, len(Reporter.get_messages()))
+        self.assertEqual(1, len(Reporter.get_messages()))
         self.assertIsInstance(Reporter.get_messages()[-1], AdminReport)
-        self.assertEquals('admin@example.org', Reporter.get_messages()[-1]._to)
+        self.assertEqual('admin@example.org', Reporter.get_messages()[-1]._to)
         Reporter.clear_messages()
 
     def test_reporter_config_all_disabled(self):
@@ -68,11 +83,11 @@ class TestReporting(unittest.TestCase):
         r = Reporter(send_conflict_messages=False,
                      send_admin_reports=False)
         r.add_messages(msgs)
-        self.assertEquals(0, len(Reporter.get_messages()))
+        self.assertEqual(0, len(Reporter.get_messages()))
 
     def test_reporter_null_message(self):
         r = Reporter(send_conflict_messages=True,
                      send_admin_reports=True)
         r.add_messages([None])
-        self.assertEquals(0, len(Reporter.get_messages()))
+        self.assertEqual(0, len(Reporter.get_messages()))
         Reporter.clear_messages()

multischleuder/test/test_smtp.py

@@ -7,7 +7,7 @@ from email.mime.text import MIMEText
 from aiosmtpd.controller import Controller
 from aiosmtpd.smtp import AuthResult, SMTP
 
-from multischleuder.reporting import ConflictMessage, AdminReport
+from multischleuder.reporting import KeyConflictMessage, AdminReport
 from multischleuder.smtp import SmtpClient, TlsMode
 from multischleuder.types import SchleuderSubscriber
 
@@ -170,7 +170,7 @@ class TestSmtpClient(unittest.TestCase):
             username='example',
             password='supersecurepassword')
         sub = SchleuderSubscriber(1, 'foo@example.org', None, 1, datetime.utcnow())
-        msg1 = ConflictMessage(
+        msg1 = KeyConflictMessage(
             schleuder='test@example.org',
             chosen=sub,
             affected=[sub],
@@ -203,7 +203,7 @@ class TestSmtpClient(unittest.TestCase):
             password='supersecurepassword')
         client.dry_run()
         sub = SchleuderSubscriber(1, 'foo@example.org', None, 1, datetime.utcnow())
-        msg1 = ConflictMessage(
+        msg1 = KeyConflictMessage(
             schleuder='test@example.org',
             chosen=sub,
             affected=[sub],

test/multischleuder.yml

@@ -40,7 +40,7 @@ smtp:
 conflict:
   interval: 3600  # 1 hour - you don't want this in production
   statefile: /tmp/conflict.json
-  template: |
+  key_template: |
     Hi {subscriber},
     
     While compiling the subscriber list of {schleuder}, your
@@ -65,8 +65,32 @@ conflict:
     message, please refer to your local Schleuder admin, or reply to this
     message.
   
-    Note that this automated message is unsigned, since MultiSchleuder does
+    Regards
-    not have access to Schleuder private keys.
+    MultiSchleuder {schleuder}
+  user_template: |
+    Hi {subscriber},
+    
+    While compiling the subscriber list of {schleuder}, your
+    key {fingerprint} was used by subscribers on multiple sub-lists with
+    different email adresses.  There may be something fishy or malicious
+    going on, or this may simply have been a mistake by you or a list admin.
+    
+    You have only been subscribed to {schleuder} using the address you
+    have been subscribed with for the *longest* time:
+      
+    {chosen}
+      
+    Please review the following adresses and talk to the admins of the
+    corresponding sub-lists to resolve this issue:
+    
+    Adress                     Sub-List
+    ------                     --------
+    {affected}
+  
+    For your convenience, this message has been sent to *all* of the above
+    adresses.  If you have any questions, or do not understand this
+    message, please refer to your local Schleuder admin, or reply to this
+    message.
   
     Regards
     MultiSchleuder {schleuder}