1 #include <u.h> 2 #include <libc.h> 3 #include <ip.h> 4 #include "dat.h" 5 #include "protos.h" 6 7 typedef struct Hdr Hdr; 8 struct Hdr { 9 uchar d[6]; 10 uchar s[6]; 11 uchar type[2]; 12 char data[1500]; 13 }; 14 #define ETHERMINTU 60 /* minimum transmit size */ 15 #define ETHERMAXTU 1514 /* maximum transmit size */ 16 #define ETHERHDRSIZE 14 /* size of an ethernet header */ 17 18 static Mux p_mux[] = 19 { 20 {"ip", 0x0800, } , 21 {"arp", 0x0806, } , 22 {"rarp", 0x0806, } , 23 {"ip6", 0x86dd, } , 24 {"pppoe_disc", 0x8863, }, 25 {"pppoe_sess", 0x8864, }, 26 {0} 27 }; 28 29 enum 30 { 31 Os, // source 32 Od, // destination 33 Oa, // source or destination 34 Ot, // type 35 }; 36 37 static Field p_fields[] = 38 { 39 {"s", Fether, Os, "source address", } , 40 {"d", Fether, Od, "destination address", } , 41 {"a", Fether, Oa, "source|destination address" } , 42 {"sd", Fether, Oa, "source|destination address" } , 43 {"t", Fnum, Ot, "type" } , 44 {0} 45 }; 46 47 static void 48 p_compile(Filter *f) 49 { 50 Mux *m; 51 52 if(f->op == '='){ 53 compile_cmp(ether.name, f, p_fields); 54 return; 55 } 56 for(m = p_mux; m->name != nil; m++) 57 if(strcmp(f->s, m->name) == 0){ 58 f->pr = m->pr; 59 f->ulv = m->val; 60 f->subop = Ot; 61 return; 62 } 63 sysfatal("unknown ethernet field or protocol: %s", f->s); 64 } 65 66 static int 67 p_filter(Filter *f, Msg *m) 68 { 69 Hdr *h; 70 71 if(m->pe - m->ps < ETHERHDRSIZE) 72 return 0; 73 74 h = (Hdr*)m->ps; 75 m->ps += ETHERHDRSIZE; 76 77 switch(f->subop){ 78 case Os: 79 return !memcmp(h->s, f->a, 6); 80 case Od: 81 return !memcmp(h->d, f->a, 6); 82 case Oa: 83 return memcmp(h->s, f->a, 6) == 0 || memcmp(h->d, f->a, 6) == 0; 84 case Ot: 85 return NetS(h->type) == f->ulv; 86 } 87 return 0; 88 } 89 90 static int 91 p_seprint(Msg *m) 92 { 93 Hdr *h; 94 uint t; 95 int len; 96 97 len = m->pe - m->ps; 98 if(len < ETHERHDRSIZE) 99 return -1; 100 101 h = (Hdr*)m->ps; 102 m->ps += ETHERHDRSIZE; 103 104 t = NetS(h->type); 105 demux(p_mux, t, t, m, &dump); 106 107 m->p = seprint(m->p, m->e, "s=%E d=%E pr=%4.4ux ln=%d", h->s, h->d, 108 t, len); 109 return 0; 110 } 111 112 Proto ether = 113 { 114 "ether", 115 p_compile, 116 p_filter, 117 p_seprint, 118 p_mux, 119 p_fields, 120 defaultframer 121 }; 122