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#include <u.h>
#include <libc.h>
#include <ip.h>
#include "dat.h"
#include "protos.h"
typedef struct Hdr Hdr;
struct Hdr {
uchar d[6];
uchar s[6];
uchar type[2];
char data[1500];
};
#define ETHERMINTU 60 /* minimum transmit size */
#define ETHERMAXTU 1514 /* maximum transmit size */
#define ETHERHDRSIZE 14 /* size of an ethernet header */
static Mux p_mux[] =
{
{"ip", 0x0800, } ,
{"arp", 0x0806, } ,
{"rarp", 0x0806, } ,
{"ip6", 0x86dd, } ,
{"pppoe_disc", 0x8863, },
{"pppoe_sess", 0x8864, },
{"eapol", 0x888e, },
{0}
};
enum
{
Os, /* source */
Od, /* destination */
Oa, /* source or destination */
Ot, /* type */
};
static Field p_fields[] =
{
{"s", Fether, Os, "source address", } ,
{"d", Fether, Od, "destination address", } ,
{"a", Fether, Oa, "source|destination address" } ,
{"sd", Fether, Oa, "source|destination address" } ,
{"t", Fnum, Ot, "type" } ,
{0}
};
static void
p_compile(Filter *f)
{
Mux *m;
if(f->op == '='){
compile_cmp(ether.name, f, p_fields);
return;
}
for(m = p_mux; 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 ethernet field or protocol: %s", f->s);
}
static int
p_filter(Filter *f, Msg *m)
{
Hdr *h;
if(m->pe - m->ps < ETHERHDRSIZE)
return 0;
h = (Hdr*)m->ps;
m->ps += ETHERHDRSIZE;
switch(f->subop){
case Os:
return !memcmp(h->s, f->a, 6);
case Od:
return !memcmp(h->d, f->a, 6);
case Oa:
return memcmp(h->s, f->a, 6) == 0 || memcmp(h->d, f->a, 6) == 0;
case Ot:
return NetS(h->type) == f->ulv;
}
return 0;
}
static int
p_seprint(Msg *m)
{
Hdr *h;
uint t;
int len;
len = m->pe - m->ps;
if(len < ETHERHDRSIZE)
return -1;
h = (Hdr*)m->ps;
m->ps += ETHERHDRSIZE;
t = NetS(h->type);
demux(p_mux, t, t, m, &dump);
m->p = seprint(m->p, m->e, "s=%E d=%E pr=%4.4ux ln=%d", h->s, h->d,
t, len);
return 0;
}
Proto ether =
{
"ether",
p_compile,
p_filter,
p_seprint,
p_mux,
"%#.4lux",
p_fields,
defaultframer
};
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