/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include <u.h>#include <libc.h>#include <ip.h>#include "dat.h"#include "protos.h" typedef struct Hdr	Hdr;struct Hdr{	uchar	hrd[2];	uchar	pro[2];	uchar	hln;	uchar	pln;	uchar	op[2];	uchar	sha[6];	uchar	spa[4];	uchar	tha[6];	uchar	tpa[4];}; enum{	ARPLEN=	28,}; enum{	Ospa,	Otpa,	Ostpa,	Osha,	Otha,	Ostha,	Opa,}; static Field p_fields[] = {	{"spa",		Fv4ip,	Ospa,	"protocol source",	} ,	{"tpa",		Fv4ip,	Otpa,	"protocol target",	} ,	{"a",		Fv4ip,	Ostpa,	"protocol source/target",	} ,	{"sha",		Fba,	Osha,	"hardware source",	} ,	{"tha",		Fba,	Otha,	"hardware target",	} ,	{"ah",	 	Fba,	Ostha,	"hardware source/target",	} ,	{0}}; static voidp_compile(Filter *f){	if(f->op == '='){		compile_cmp(arp.name, f, p_fields);		return;	}	sysfatal("unknown arp field: %s", f->s);} static intp_filter(Filter *f, Msg *m){	Hdr *h; 	if(m->pe - m->ps < ARPLEN)		return 0; 	h = (Hdr*)m->ps;	m->ps += ARPLEN; 	switch(f->subop){	case Ospa:		return h->pln == 4 && NetL(h->spa) == f->ulv;	case Otpa:		return h->pln == 4 && NetL(h->tpa) == f->ulv;	case Ostpa:		return h->pln == 4 && (NetL(h->tpa) == f->ulv ||			NetL(h->spa) == f->ulv);	case Osha:		return memcmp(h->sha, f->a, h->hln) == 0;	case Otha:		return memcmp(h->tha, f->a, h->hln) == 0;	case Ostha:		return memcmp(h->sha, f->a, h->hln)==0			||memcmp(h->tha, f->a, h->hln)==0;	}	return 0;} static intp_seprint(Msg *m){	Hdr *h; 	if(m->pe - m->ps < ARPLEN)		return -1; 	h = (Hdr*)m->ps;	m->ps += ARPLEN; 	/* no next protocol */	m->pr = nil; 	m->p = seprint(m->p, m->e, "op=%1d len=%1d/%1d spa=%V sha=%E tpa=%V tha=%E",			NetS(h->op), h->pln, h->hln,			h->spa, h->sha, h->tpa, h->tha);	return 0;} Proto arp ={	"arp",	p_compile,	p_filter,	p_seprint,	nil,	nil,	p_fields,	defaultframer,}; Proto rarp ={	"rarp",	p_compile,	p_filter,	p_seprint,	nil,	nil,	p_fields,	defaultframer,};