receiver receiverid challenge and find corresponding key

owrx/receiverid.py

@@ -0,0 +1,63 @@
+import re
+import logging
+from owrx.config import Config
+
+logger = logging.getLogger(__name__)
+
+
+keyRegex = re.compile("^([a-zA-Z]+)-([0-9a-f]{32})-([0-9a-f]{64})$")
+keyChallengeRegex = re.compile("^([a-zA-Z]+)-([0-9a-f]{32})-([0-9a-f]{32})$")
+headerRegex = re.compile("^ReceiverId (.*)$")
+
+
+class KeyException(Exception):
+    pass
+
+
+class Key(object):
+    def __init__(self, keyString):
+        matches = keyRegex.match(keyString)
+        if not matches:
+            raise KeyException("invalid key format")
+        self.source = matches.group(1)
+        self.id = matches.group(2)
+        self.secret = matches.group(3)
+
+
+class KeyChallenge(object):
+    def __init__(self, challengeString):
+        matches = keyChallengeRegex.match(challengeString)
+        if not matches:
+            raise KeyException("invalid key challenge format")
+        self.source = matches.group(1)
+        self.id = matches.group(2)
+        self.challenge = matches.group(3)
+
+
+class KeyResponse(object):
+    def __str__(self):
+        return "TODO"
+
+
+class ReceiverId(object):
+    @staticmethod
+    def getResponseHeader(requestHeader):
+        matches = headerRegex.match(requestHeader)
+        if not matches:
+            raise KeyException("invalid authorization header")
+        challenge = KeyChallenge(matches.group(1))
+        key = ReceiverId.findKey(challenge)
+        # TODO sign challenge and respond
+
+    @staticmethod
+    def findKey(challenge):
+        def parseKey(keyString):
+            try:
+                return Key(keyString)
+            except KeyError as e:
+                logger.error(e)
+        keys = [key for key in (parseKey(keyString) for keyString in Config.get()['receiver_keys']) if key is not None]
+        matching_keys = [key for key in keys if key.source == challenge.source and key.id == challenge.id]
+        if matching_keys:
+            return matching_keys[0]
+        return None