client: new root sigs only counted once per keyid

When verifying newly downloaded root metadata with the keys listed in the root metadata being verified, multiple signatures with the same keyid should not be counted towards the threshold. A keyid should only count once towards the threshold. This fixes the _verify_root_self_signed() method introduced in PR #1101 to ensure that keyids are only counted once when verifying a threshold of new root signatures. Signed-off-by: Joshua Lock <[email protected]>
theupdateframework · Nov 24, 2020 · 83ac7be · 83ac7be
1 parent 71cb004
commit 83ac7be
Showing 1 changed file with 3 additions and 3 deletions.
diff --git a/tuf/client/updater.py b/tuf/client/updater.py
@@ -1385,7 +1385,7 @@ def _verify_root_self_signed(self, signable):
     signatures = signable['signatures']
     signed = securesystemslib.formats.encode_canonical(
         signable['signed']).encode('utf-8')
-    validated = 0
+    verified_sig_keyids = set()
 
     for signature in signatures:
       keyid = signature['keyid']
@@ -1403,9 +1403,9 @@ def _verify_root_self_signed(self, signable):
       valid_sig = securesystemslib.keys.verify_signature(key, signature, signed)
 
       if valid_sig:
-        validated = validated + 1
+        verified_sig_keyids.add(keyid)
 
-    if validated >= threshold:
+    if len(verified_sig_keyids) >= threshold:
       return True
     return False