diff options
| -rw-r--r-- | lib/libpcap/gencode.c | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/lib/libpcap/gencode.c b/lib/libpcap/gencode.c index 4e858f001e7..a9fb14be943 100644 --- a/lib/libpcap/gencode.c +++ b/lib/libpcap/gencode.c @@ -1,4 +1,4 @@ -/* $OpenBSD: gencode.c,v 1.55 2020/08/03 03:40:02 dlg Exp $ */ +/* $OpenBSD: gencode.c,v 1.56 2020/09/12 09:27:22 kn Exp $ */ /* * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998 @@ -912,16 +912,33 @@ gen_linktype(proto) case DLT_LOOP: case DLT_ENC: case DLT_NULL: - /* XXX */ + { + int v; + if (proto == ETHERTYPE_IP) - return (gen_cmp(0, BPF_W, (bpf_int32)htonl(AF_INET))); + v = AF_INET; #ifdef INET6 else if (proto == ETHERTYPE_IPV6) - return (gen_cmp(0, BPF_W, (bpf_int32)htonl(AF_INET6))); + v = AF_INET6; #endif /* INET6 */ else return gen_false(); + + /* + * For DLT_NULL, the link-layer header is a 32-bit word + * containing an AF_ value in *host* byte order, and for + * DLT_ENC, the link-layer header begins with a 32-bit + * word containing an AF_ value in host byte order. + * + * For DLT_LOOP, the link-layer header is a 32-bit + * word containing an AF_ value in *network* byte order. + */ + if (linktype != DLT_LOOP) + v = htonl(v); + + return (gen_cmp(0, BPF_W, (bpf_int32)v)); break; + } case DLT_PFLOG: if (proto == ETHERTYPE_IP) return (gen_cmp(offsetof(struct pfloghdr, af), BPF_B, |