Sender verification and virtual alias map from inventory

filter_plugins/filters.py

@@ -0,0 +1,64 @@
+#!/usr/bin/env python3
+
+def validate_aliases(aliases):
+	for alias in aliases:
+		unknown_attributes = alias.keys() - {'addresses', 'senders', 'receivers', 'senders_and_receivers'}
+		if unknown_attributes:
+			raise ValueError('Unknown alias attributes: ' + ', '.join(unknown_attributes))
+		for address in alias['addresses']:
+			if not address.islower():
+				raise ValueError(f'Aliases are not case-sensitive. Make "{address}" all-lowercase!')
+			if address.strip() != address:
+				raise ValueError(f'Remove surrounding whitespace in "{address}"!')
+
+class FilterModule(object):
+	def filters(self):
+		return {
+				'postfix_resolve_senders': self.postfix_resolve_senders,
+				'postfix_resolve_receivers': self.postfix_resolve_receivers,
+			}
+
+	def postfix_resolve_senders(self, aliases, match_sender_domain, allow_sender_domains=tuple()):
+		validate_aliases(aliases)
+		sender_suffix = '@' + match_sender_domain
+		address_sender_address_map = {}
+		for alias in aliases:
+			for address in alias['addresses']:
+				address_sender_address_map.setdefault(address, set())
+				address_sender_address_map[address] |= set(alias.get('senders', []))
+				address_sender_address_map[address] |= set(alias.get('senders_and_receivers', []))
+		for _ in range(100):
+			done = True
+			for address, senders in address_sender_address_map.items():
+				for sender in set(senders):
+					if sender.endswith(sender_suffix):
+						continue
+					done = False
+					if sender not in address_sender_address_map:
+						raise Exception(f'Address does not resolve to sender address: {sender}')
+					senders.remove(sender)
+					senders |= address_sender_address_map[sender]
+			if done:
+				break
+		if not done:
+			raise Exception('Recursion limit reached')
+
+		address_sender_name_map = {}
+		for address, senders in address_sender_address_map.items():
+			address_sender_name_map[address] = set()
+			for sender in senders:
+				username = sender[:-len(sender_suffix)]
+				address_sender_name_map[address].add(username)
+				for domain in allow_sender_domains:
+					address_sender_name_map[address].add(f'{username}@{domain}')
+		return address_sender_name_map
+
+	def postfix_resolve_receivers(self, aliases):
+		validate_aliases(aliases)
+		address_receiver_address_map = {}
+		for alias in aliases:
+			for address in alias['addresses']:
+				address_receiver_address_map.setdefault(address, set())
+				address_receiver_address_map[address] |= set(alias.get('receivers', []))
+				address_receiver_address_map[address] |= set(alias.get('senders_and_receivers', []))
+		return address_receiver_address_map