Hi guys. I'm diggin some bpf stuff and i can't figure out, why there are 3 types of data representations: words, halfwords and bytes? I mean how can i know, which one is best in a place to use? In some basic example, e.g. for packet capturing, considering BPF's manual, i use for ETHERTYPE in the ethernet header a halfword representation, but for a IP address - word representation. Let's say we have some read instructions:
BPF_STMT(BPF_LD+BPF_H+BPF_ABS, 12), BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, ETHERTYPE_IP, X, Y), .... BPF_STMT(BPF_LD+BPF_W+BPF_ABS, 26), BPF_JUMP(BPF_JMP+BPF+JEQ+BPF_K, 0xABABABAB, X,Y) Can someone explain? Thanks! _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
