Add some check

3 years ago · 12b601cfcd
parent b74ebe03b4
commit 12b601cfcd
1 changed files with 3 additions and 0 deletions
--- a/main.py
+++ b/main.py
@ -160,6 +160,9 @@ def handle_ip_packet(ip_packet, conn, tun_iface, config):
    ip_packet_packed = ip_packet.to_byte_string()
    ip_packet_length = struct.pack('>I', len(ip_packet_packed))

+    if len(ip_packet_packed) != ip_packet.header.total_length:
+        raise RuntimeError('invalid "total length" header value')
+
    buf = MAGIC + ip_packet_length + ip_packet_packed

    if ip_packet.header.dst == config.iface_addr: