leading single colons are just as bad as trailing ones

diff --git a/dns/ipv6.py b/dns/ipv6.py
index faadb7c294b1756cf0a9d6ee553709dcb736b83b..f0e522c0c451c53d08b2f6dd514cc87871e2048a 100644 (file)
--- a/dns/ipv6.py
+++ b/dns/ipv6.py
@@ -125,6 +125,8 @@ def inet_aton(text, ignore_scope=False):
         raise dns.exception.SyntaxError
     elif text.endswith(b':') and not text.endswith(b'::'):
         raise dns.exception.SyntaxError
+    elif text.startswith(b':') and not text.startswith(b'::'):
+        raise dns.exception.SyntaxError
     elif text == b'::':
         text = b'0::'
     #