#include "u.h"#include "../port/lib.h"#include "mem.h"#include "dat.h"#include "fns.h"#include "../port/error.h" #include "ip.h" typedef struct Etherhdr Etherhdr;struct Etherhdr{	uchar	d[6];	uchar	s[6];	uchar	t[2];}; static void	etherread(void *a);static void	etherbind(Ipifc *ifc, int argc, char **argv);static void	etherunbind(Ipifc *ifc);static void	etherbwrite(Ipifc *ifc, Block *bp, int version, uchar *ip);static void	etheraddmulti(Ipifc *ifc, uchar *a, uchar *ia);static void	etherremmulti(Ipifc *ifc, uchar *a, uchar *ia);static Block*	multicastarp(Fs *f, Arpent *a, Medium*, uchar *mac);static void	sendarp(Ipifc *ifc, Arpent *a);static void	sendgarp(Ipifc *ifc, uchar*);static int	multicastea(uchar *ea, uchar *ip);static void	recvarpproc(void*); Medium ethermedium ={.name=		"ether",.hsize=		14,.minmtu=	60,.maxmtu=	1514,.maclen=	6,.bind=		etherbind,.unbind=	etherunbind,.bwrite=	etherbwrite,.addmulti=	etheraddmulti,.remmulti=	etherremmulti,.ares=		arpenter,.areg=		sendgarp,}; Medium gbemedium ={.name=		"gbe",.hsize=		14,.minmtu=	60,.maxmtu=	9014,.maclen=	6,.bind=		etherbind,.unbind=	etherunbind,.bwrite=	etherbwrite,.addmulti=	etheraddmulti,.remmulti=	etherremmulti,.ares=		arpenter,.areg=		sendgarp,}; typedef struct	Etherrock Etherrock;struct Etherrock{	Fs	*f;		/* file system we belong to */	Proc	*arpp;		/* arp process */	Proc	*readp;		/* reading process */	Chan	*mchan;		/* Data channel */	Chan	*achan;		/* Arp channel */	Chan	*cchan;		/* Control channel */}; /* *  ethernet arp request */enum{	ETARP		= 0x0806,	ETIP		= 0x0800,	ARPREQUEST	= 1,	ARPREPLY	= 2,};typedef struct Etherarp Etherarp;struct Etherarp{	uchar	d[6];	uchar	s[6];	uchar	type[2];	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];};  /* *  called to bind an IP ifc to an ethernet device *  called with ifc wlock'd */static voidetherbind(Ipifc *ifc, int argc, char **argv){	Chan *mchan, *cchan, *achan;	char addr[2*NAMELEN];	char dir[2*NAMELEN];	char *buf;	int n;	char *ptr;	Etherrock *er; 	if(argc < 2)		error(Ebadarg); 	mchan = cchan = achan = nil;	buf = nil;	if(waserror()){		if(mchan != nil)			cclose(mchan);		if(cchan != nil)			cclose(cchan);		if(achan != nil)			cclose(achan);		if(buf != nil)			free(buf);		nexterror(); 	} 	/*	 *  open ip conversation	 *	 *  the dial will fail if the type is already open on	 *  this device.	 */	snprint(addr, sizeof(addr), "%s!0x800", argv[2]);	mchan = chandial(addr, nil, dir, &cchan); 	/*	 *  get mac address	 */	snprint(addr, sizeof(addr), "%s/stats", dir);	buf = smalloc(512);	achan = namec(addr, Aopen, OREAD, 0);	n = devtab[achan->type]->read(achan, buf, 511, 0);	cclose(achan);	buf[n] = 0; 	ptr = strstr(buf, "addr: ");	if(!ptr)		error(Eio);	ptr += 6; 	parsemac(ifc->mac, ptr, 6); 	/* 	 *  open arp conversation	 */	snprint(addr, sizeof(addr), "%s!0x806", argv[2]);	achan = chandial(addr, nil, nil, nil); 	er = smalloc(sizeof(*er));	er->mchan = mchan;	er->cchan = cchan;	er->achan = achan;	er->f = ifc->conv->p->f;	ifc->arg = er; 	free(buf);	poperror(); 	kproc("etherread", etherread, ifc);	kproc("recvarpproc", recvarpproc, ifc);} /* *  called with ifc wlock'd */static voidetherunbind(Ipifc *ifc){	Etherrock *er = ifc->arg; 	if(er->readp)		postnote(er->readp, 1, "unbind", 0);	if(er->arpp)		postnote(er->arpp, 1, "unbind", 0); 	/* wait for readers to die */	while(er->arpp != 0 || er->readp != 0)		tsleep(&up->sleep, return0, 0, 300); 	if(er->mchan != nil)		cclose(er->mchan);	if(er->achan != nil)		cclose(er->achan);	if(er->cchan != nil)		cclose(er->cchan); 	free(er);} /* *  called by ipoput with a single block to write with ifc rlock'd */static voidetherbwrite(Ipifc *ifc, Block *bp, int version, uchar *ip){	Etherhdr *eh;	Arpent *a;	uchar mac[6];	Etherrock *er = ifc->arg; 	/* get mac address of destination */	a = arpget(er->f->arp, bp, version, ifc->m, ip, mac);	if(a){		/* check for broadcast or multicast */		bp = multicastarp(er->f, a, ifc->m, mac);		if(bp == nil){			sendarp(ifc, a);			return;		}	} 	/* make it a single block with space for the ether header */	bp = padblock(bp, ifc->m->hsize);	if(bp->next)		bp = concatblock(bp);	if(BLEN(bp) < ifc->minmtu)		bp = adjustblock(bp, ifc->minmtu);	eh = (Etherhdr*)bp->rp; 	/* copy in mac addresses and ether type */	memmove(eh->s, ifc->mac, sizeof(eh->s));	memmove(eh->d, mac, sizeof(eh->d));	switch(version){	case V4:		eh->t[0] = 0x08;		eh->t[1] = 0x00;		break;	case V6:		eh->t[0] = 0x86;		eh->t[1] = 0xDD;		break;	} 	devtab[er->mchan->type]->bwrite(er->mchan, bp, 0);	ifc->out++;} /* *  process to read from the ethernet */static voidetherread(void *a){	Ipifc *ifc;	Block *bp;	Etherrock *er; 	ifc = a;	er = ifc->arg;	er->readp = up;	/* hide identity under a rock for unbind */	if(waserror()){		er->readp = 0;		pexit("hangup", 1);	}	for(;;){		bp = devtab[er->mchan->type]->bread(er->mchan, ifc->maxmtu, 0);		if(!canrlock(ifc)){			freeb(bp);			continue;		}		if(waserror()){			runlock(ifc);			nexterror();		}		ifc->in++;		bp->rp += ifc->m->hsize;		if(ifc->lifc == nil)			freeb(bp);		else			ipiput(er->f, ifc->lifc->local, bp);		runlock(ifc);		poperror();	}} static voidetheraddmulti(Ipifc *ifc, uchar *a, uchar *){	uchar mac[6];	char buf[64];	Etherrock *er = ifc->arg; 	multicastea(mac, a);	sprint(buf, "addmulti %E", mac);	devtab[er->cchan->type]->write(er->cchan, buf, strlen(buf), 0);} static voidetherremmulti(Ipifc *ifc, uchar *a, uchar *){	uchar mac[6];	char buf[64];	Etherrock *er = ifc->arg; 	multicastea(mac, a);	sprint(buf, "remmulti %E", mac);	devtab[er->cchan->type]->write(er->cchan, buf, strlen(buf), 0);} /* *  send an ethernet arp *  (only v4, v6 uses the neighbor discovery, rfc1970) */static voidsendarp(Ipifc *ifc, Arpent *a){	int n;	Block *bp;	Etherarp *e;	Etherrock *er = ifc->arg; 	/* don't do anything if it's been less than a second since the last */	if(msec - a->time < 1000){		arprelease(er->f->arp, a);		return;	} 	/* remove all but the last message */	while((bp = a->hold) != nil){		if(bp == a->last)			break;		a->hold = bp->list;		freeblist(bp);	} 	/* try to keep it around for a second more */	a->time = msec;	arprelease(er->f->arp, a); 	n = sizeof(Etherarp);	if(n < a->type->minmtu)		n = a->type->minmtu;	bp = allocb(n);	memset(bp->rp, 0, n);	e = (Etherarp*)bp->rp;	memmove(e->tpa, a->ip+IPv4off, sizeof(e->tpa));	ipv4local(ifc, e->spa);	memmove(e->sha, ifc->mac, sizeof(e->sha));	memset(e->d, 0xff, sizeof(e->d));		/* ethernet broadcast */	memmove(e->s, ifc->mac, sizeof(e->s)); 	hnputs(e->type, ETARP);	hnputs(e->hrd, 1);	hnputs(e->pro, ETIP);	e->hln = sizeof(e->sha);	e->pln = sizeof(e->spa);	hnputs(e->op, ARPREQUEST);	bp->wp += n; 	n = devtab[er->achan->type]->bwrite(er->achan, bp, 0);	if(n < 0)		print("arp: send: %r\n");} /* *  send a gratuitous arp to refresh arp caches */static voidsendgarp(Ipifc *ifc, uchar *ip){	int n;	Block *bp;	Etherarp *e;	Etherrock *er = ifc->arg; 	/* don't arp for our initial non address */	if(ipcmp(ip, IPnoaddr) == 0)		return; 	n = sizeof(Etherarp);	if(n < ifc->m->minmtu)		n = ifc->m->minmtu;	bp = allocb(n);	memset(bp->rp, 0, n);	e = (Etherarp*)bp->rp;	memmove(e->tpa, ip+IPv4off, sizeof(e->tpa));	memmove(e->spa, ip+IPv4off, sizeof(e->spa));	memmove(e->sha, ifc->mac, sizeof(e->sha));	memset(e->d, 0xff, sizeof(e->d));		/* ethernet broadcast */	memmove(e->s, ifc->mac, sizeof(e->s)); 	hnputs(e->type, ETARP);	hnputs(e->hrd, 1);	hnputs(e->pro, ETIP);	e->hln = sizeof(e->sha);	e->pln = sizeof(e->spa);	hnputs(e->op, ARPREQUEST);	bp->wp += n; 	n = devtab[er->achan->type]->bwrite(er->achan, bp, 0);	if(n < 0)		print("garp: send: %r\n");} static voidrecvarp(Ipifc *ifc){	int n;	Block *ebp, *rbp;	Etherarp *e, *r;	uchar ip[IPaddrlen];	Etherrock *er = ifc->arg; 	ebp = devtab[er->achan->type]->bread(er->achan, ifc->maxmtu, 0);	if(ebp == nil) {		print("arp: rcv: %r\n");		return;	} 	e = (Etherarp*)ebp->rp;	switch(nhgets(e->op)) {	default:		break; 	case ARPREPLY:		arpenter(er->f, V4, e->spa, e->sha, sizeof(e->sha), 0);		break; 	case ARPREQUEST:		/* don't answer arps till we know who we are */		if(ifc->lifc == 0)			break; 		/* check for someone that think's they're me */		v4tov6(ip, e->spa);		if(iplocalonifc(ifc, ip) || ipproxyifc(er->f, ifc, ip)){			if(memcmp(e->sha, ifc->mac, sizeof(e->sha)) != 0)				print("arp: 0x%E also has ip addr %V\n", e->sha, e->spa);		} else {			if(memcmp(e->sha, ifc->mac, sizeof(e->sha)) == 0){				print("arp: %V also has ether addr %E\n", e->spa, e->sha);				break;			}		} 		/* refresh what we know about sender */		arpenter(er->f, V4, e->spa, e->sha, sizeof(e->sha), 1); 		/* answer only requests for our address or systems we're proxying for */		v4tov6(ip, e->tpa);		if(!iplocalonifc(ifc, ip))		if(!ipproxyifc(er->f, ifc, ip))			break; /* print("arp: rem %I %E (for %I)\n", e->spa, e->sha, e->tpa); /**/ 		n = sizeof(Etherarp);		if(n < ifc->minmtu)			n = ifc->minmtu;		rbp = allocb(n);		r = (Etherarp*)rbp->rp;		memset(r, 0, sizeof(Etherarp));		hnputs(r->type, ETARP);		hnputs(r->hrd, 1);		hnputs(r->pro, ETIP);		r->hln = sizeof(r->sha);		r->pln = sizeof(r->spa);		hnputs(r->op, ARPREPLY);		memmove(r->tha, e->sha, sizeof(r->tha));		memmove(r->tpa, e->spa, sizeof(r->tpa));		memmove(r->sha, ifc->mac, sizeof(r->sha));		memmove(r->spa, e->tpa, sizeof(r->spa));		memmove(r->d, e->sha, sizeof(r->d));		memmove(r->s, ifc->mac, sizeof(r->s));		rbp->wp += n; 		n = devtab[er->achan->type]->bwrite(er->achan, rbp, 0);		if(n < 0)			print("arp: write: %r\n");	}	freeb(ebp);} static voidrecvarpproc(void *v){	Ipifc *ifc = v;	Etherrock *er = ifc->arg; 	er->arpp = up;	if(waserror()){		er->arpp = 0;		pexit("hangup", 1);	}

Lines 1–500 of 565. Load more