diff options
Diffstat (limited to 'extensions/libxt_bpf.man')
| -rw-r--r-- | extensions/libxt_bpf.man | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/extensions/libxt_bpf.man b/extensions/libxt_bpf.man index d6da2043..b79c21db 100644 --- a/extensions/libxt_bpf.man +++ b/extensions/libxt_bpf.man @@ -28,7 +28,7 @@ without the comments or trailing whitespace: .IP 4 # number of instructions .br -48 0 0 9 # load byte ip->proto +48 0 0 9 # load byte ip\->proto .br 21 0 1 6 # jump equal IPPROTO_TCP .br @@ -44,7 +44,7 @@ Or instead, you can invoke the nfbpf_compile utility. .IP iptables \-A OUTPUT \-m bpf \-\-bytecode "`nfbpf_compile RAW 'ip proto 6'`" \-j ACCEPT .PP -Or use tcpdump -ddd. In that case, generate BPF targeting a device with the +Or use tcpdump \-ddd. In that case, generate BPF targeting a device with the same data link type as the xtables match. Iptables passes packets from the network layer up, without mac layer. Select a device with data link type RAW, such as a tun device: @@ -53,8 +53,8 @@ ip tuntap add tun0 mode tun .br ip link set tun0 up .br -tcpdump -ddd -i tun0 ip proto 6 +tcpdump \-ddd \-i tun0 ip proto 6 .PP -See tcpdump -L -i $dev for a list of known data link types for a given device. +See tcpdump \-L \-i $dev for a list of known data link types for a given device. .PP You may want to learn more about BPF from FreeBSD's bpf(4) manpage. |