Date: Thu, 16 Jun 2005 21:51:31 +1200 From: Matthew Luckie <mjl@luckie.org.nz> To: freebsd-current@freebsd.org Subject: BPF writes on DLT_NULL devices Message-ID: <42B14BA3.5050700@luckie.org.nz>
next in thread | raw e-mail | index | archive | help
Hi -current I'm writing to see if I can find someone to review and commit a patch I submitted to PR 82157 as suggested by re@ http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/82157 The patch attempts to tidy up the mess that is BPF write on DLT_NULL devices. Some of these devices are handy to write to, e.g. tun, gif, and gre. There are a number of limitations and flaws in the -current code; namely * not all DLT_NULL devices support bpf write, including gif and gre * write() will fail if trying to send a packet larger than the IP MTU less 4 bytes, due to bpf_movein not taking into account the psuedo header * if_loop.c checks for bpf write in if_simloop; however the only device passing a packet via BPF to that function is looutput, yet looutput will return EAFNOSUPPORT because AF_UNSPEC is not checked in that function. Full details, including test code and a patch is available in the PR Any takers? Matthew
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?42B14BA3.5050700>