Date: Mon, 12 Jan 2009 16:02:11 -0800 From: "Peter Steele" <psteele@maxiscale.com> To: <freebsd-net@freebsd.org> Subject: Broadcast packet not being sent Message-ID: <2ACA3DE8F9758A48B8BE2C7A847F91F247A128@polaris.maxiscale.com>
next in thread | raw e-mail | index | archive | help
I am using scapy to construct a UDP broadcast packet. The code I'm using is: =20 packet=3DEther(dst=3D"ff:ff:ff:ff:ff:ff")/IP(dst=3D"255.255.255.255")/UDP= (dpor t=3D33333)/payload sendp(packet) Send 1 packets. =20 This works fine when I have an IP assigned to the box. However, when no IP is assigned, I get the following messages: The sendp generates these warnings: =20 WARNING: No route found for IPv6 destination :: (no default route?) WARNING: No route found (no default route?) WARNING: No route found (no default route?) WARNING: No route found (no default route?) =20 Sent 1 packets. =20 I assume these warnings are okay, since of course there can't be a route in a scenario like the one I'm using. It's the same environment a DHCP client would face. However, despite scapy saying the packet was sent, it does not in fact leave the machine (I've confirmed this with tcpdump). As I said, if the box has an IP address, then the packet is sent as expected, but that defeats the purpose since we are developing a custom DHCP-like protocol. =20 The only think suspicious that I am seeing is this error in /var/log/messages: =20 Jan 12 16:13:52 kernel: looutput: af=3D31 unexpected =20 I get one of these each time I try to send a broadcast when no IP is assigned. I did an google search but did not any useful hits on this. If anyone here has any idea what's going on, I'd appreciate some feedback. I think I have the correct packet constructed, but clearly something is wrong, and it may very well be user error. =20 Peter =20
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?2ACA3DE8F9758A48B8BE2C7A847F91F247A128>