Don't require --publickey, but print better error message.

1 files changed, 6 insertions, 1 deletions

diff --git a/tools/certtools.py b/tools/certtools.py
index 405aabd..ccbc76e 100644
--- a/tools/certtools.py
+++ b/tools/certtools.py
@@ -219,7 +219,12 @@ def encode_signature(hash_alg, signature_alg, unpacked_signature):
 
 def check_signature(baseurl, signature, data, publickey=None):
     if publickey == None:
-        publickey = base64.decodestring(publickeys[baseurl])
+        if baseurl in publickeys:
+            publickey = base64.decodestring(publickeys[baseurl])
+        else:
+            print >>sys.stderr, "Public key for", baseurl, \
+                "not found, specify key file with --publickey"
+            sys.exit(1)
     (hash_alg, signature_alg, unpacked_signature) = decode_signature(signature)
     assert hash_alg == 4, \
         "hash_alg is %d, expected 4" % (hash_alg,) # sha256