Also replace positional calls with explicit keyword argument calls in
test/ganeti.serializer_unittest.py

Signed-off-by: Balazs Lecz <[email protected]>
---
 lib/serializer.py                  |   21 ++++++++++++++++++---
 test/ganeti.serializer_unittest.py |   27 ++++++++++++++++++++-------
 2 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/lib/serializer.py b/lib/serializer.py
index b568497..895f33e 100644
--- a/lib/serializer.py
+++ b/lib/serializer.py
@@ -101,11 +101,13 @@ def LoadJson(txt):
   return simplejson.loads(txt)
 
 
-def DumpSignedJson(data, key, salt=None):
+def DumpSignedJson(data, key, salt=None, key_selector=None):
   """Serialize a given object and authenticate it.
 
   @param data: the data to serialize
   @param key: shared hmac key
+  @param key_selector: name/id that identifies the key (in case there are
+    multiple keys in use, e.g. in a multi-cluster environment)
   @return: the string representation of data signed by the hmac key
 
   """
@@ -117,6 +119,8 @@ def DumpSignedJson(data, key, salt=None):
     'salt': salt,
     'hmac': hmac.new(key, salt + txt, sha1).hexdigest(),
   }
+  if key_selector:
+    signed_dict["key_selector"] = key_selector
   return DumpJson(signed_dict, indent=False)
 
 
@@ -124,7 +128,9 @@ def LoadSignedJson(txt, key):
   """Verify that a given message was signed with the given key, and load it.
 
   @param txt: json-encoded hmac-signed message
-  @param key: shared hmac key
+  @param key: the shared hmac key or a callable taking one argument (the key
+    selector), which returns the hmac key belonging to the key selector.
+    Typical usage is to pass a reference to the get method of a dict.
   @rtype: tuple of original data, string
   @return: original data, salt
   @raises errors.SignatureError: if the message signature doesn't verify
@@ -140,7 +146,16 @@ def LoadSignedJson(txt, key):
   except KeyError:
     raise errors.SignatureError('Invalid external message')
 
-  if hmac.new(key, salt + msg, sha1).hexdigest() != hmac_sign:
+  if callable(key):
+    key_selector = signed_dict.get("key_selector", None)
+    hmac_key = key(key_selector)
+    if not hmac_key:
+      raise errors.SignatureError("No key with key selector '%s' found" %
+                                  key_selector)
+  else:
+    hmac_key = key
+
+  if hmac.new(hmac_key, salt + msg, sha1).hexdigest() != hmac_sign:
     raise errors.SignatureError('Invalid Signature')
 
   return LoadJson(msg), salt
diff --git a/test/ganeti.serializer_unittest.py 
b/test/ganeti.serializer_unittest.py
index 11a60e6..ed703d9 100755
--- a/test/ganeti.serializer_unittest.py
+++ b/test/ganeti.serializer_unittest.py
@@ -68,16 +68,29 @@ class TestSerializer(testutils.GanetiTestCase):
     DumpSigned = serializer.DumpSigned
 
     for data in self._TESTDATA:
-      self.assertEqualValues(LoadSigned(DumpSigned(data, "mykey"), "mykey"),
+      self.assertEqualValues(LoadSigned(DumpSigned(data,
+                                                   key="mykey"),
+                                        key="mykey"),
                              (data, ''))
-      self.assertEqualValues(LoadSigned(DumpSigned(data, "myprivatekey",
-                                                   "mysalt"),
-                                        "myprivatekey"),
+      self.assertEqualValues(LoadSigned(DumpSigned(data,
+                                                   key="myprivatekey",
+                                                   salt="mysalt"),
+                                        key="myprivatekey"),
                              (data, "mysalt"))
 
-    self.assertRaises(errors.SignatureError, serializer.LoadSigned,
-                      serializer.DumpSigned("test", "myprivatekey"),
-                      "myotherkey")
+      keydict = {"mykey_id": "myprivatekey"}
+      self.assertEqualValues(LoadSigned(DumpSigned(data,
+                                                   key="myprivatekey",
+                                                   salt="mysalt",
+                                                   key_selector="mykey_id"),
+                                        key=keydict.get),
+                             (data, "mysalt"))
+
+    self.assertRaises(errors.SignatureError,
+                      serializer.LoadSigned,
+                      serializer.DumpSigned("test",
+                                            key="myprivatekey"),
+                      key="myotherkey")
 
 
 if __name__ == '__main__':
-- 
1.6.6.2

Reply via email to