ref: 556618eb07d1ac6e2c629a60acd53c45d53261be
dir: /sys/src/cmd/ip/snoopy/vlan.c/
#include <u.h> #include <libc.h> #include <ip.h> #include "dat.h" #include "protos.h" extern Mux ethertypes[]; typedef struct Hdr Hdr; struct Hdr { uchar tag[2]; uchar type[2]; }; enum { Ov, /* vlan */ Oq, /* qprio */ Ot, /* type */ }; static Field p_fields[] = { {"v", Fnum, Ov, "vlan id" } , {"q", Fnum, Oq, "queue prio" } , {"t", Fnum, Ot, "type" } , {0} }; static void p_compile(Filter *f) { Mux *m; if(f->op == '='){ compile_cmp(vlan.name, f, p_fields); return; } for(m = ethertypes; m->name != nil; m++) if(strcmp(f->s, m->name) == 0){ f->pr = m->pr; f->ulv = m->val; f->subop = Ot; return; } sysfatal("unknown vlan field or protocol: %s", f->s); } static int p_filter(Filter *f, Msg *m) { Hdr *h; if(m->pe - m->ps < 4) return 0; h = (Hdr*)m->ps; m->ps += 4; switch(f->subop){ case Ov: return (NetS(h->tag) & 0xFFF) == f->ulv; case Oq: return (NetS(h->tag) >> 12) == f->ulv; case Ot: return NetS(h->type) == f->ulv; } return 0; } static int p_seprint(Msg *m) { uint v, q, t; int len; Hdr *h; len = m->pe - m->ps; if(len < 4) return -1; h = (Hdr*)m->ps; m->ps += 4; q = NetS(h->tag) >> 12; v = NetS(h->tag) & 0xFFF; t = NetS(h->type); demux(ethertypes, t, t, m, &dump); m->p = seprint(m->p, m->e, "v=%ud q=%ux pr=%4.4ux ln=%d", v, q, t, len); return 0; } Proto vlan = { "vlan", p_compile, p_filter, p_seprint, ethertypes, "%#.4lux", p_fields, defaultframer };