electrum

commit 1b14a18b1addbc264800cd6961bdbe02ac3c7d2b
parent d371e1c807f3cf8b0a65d03f470f104baf5416cc
Author: ThomasV <thomasv@electrum.org>
Date:   Thu, 30 Mar 2017 05:55:02 +0200

sanitize pass_checkpoint

Diffstat:
M
lib/blockchain.py
 | 
10
+++++++++-

1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/lib/blockchain.py b/lib/blockchain.py
@@ -55,9 +55,17 @@ class Blockchain(util.PrintError):
         t.start()
 
     def pass_checkpoint(self, header):
+        if type(header) is not dict:
+            return False
         if header.get('block_height') != self.checkpoint_height:
             return True
-        return self.hash_header(header) == self.checkpoint_hash
+        if header.get('prev_block_hash') is None:
+            header['prev_block_hash'] = '00'*32
+        try:
+            _hash = self.hash_header(header)
+        except:
+            return False
+        return _hash == self.checkpoint_hash
 
     def verify_header(self, header, prev_header, bits, target):
         prev_hash = self.hash_header(prev_header)