GRE_VERSION_1 203 drivers/net/ppp/pptp.c hdr->gre_hd.flags = GRE_KEY | GRE_VERSION_1 | GRE_SEQ; GRE_VERSION_1 175 net/netfilter/nf_conntrack_proto_gre.c if (!grehdr || (grehdr->flags & GRE_VERSION) != GRE_VERSION_1) { GRE_VERSION_1 305 net/netfilter/nf_nat_proto.c case GRE_VERSION_1: