From 2a10e87cea7981243b71a597ec462a96d0a4ef82 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 16 Mar 1999 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1999-03-16

---
 boot/boot.c      |   6 +-
 boot/boot.h      |   1 +
 ip/devip.c       |  11 +-
 ip/esp.c         | 645 +++++++++++++++++++++++++++++++++
 ip/ip.h          |  17 +-
 ip/ipaux.c       |  20 --
 ip/netlog.c      |  13 +-
 pc/devether.c    |  16 +-
 port/devbridge.c | 907 +++++++++++++++++++++++++++++++++++++++++++++++
 port/devroot.c   |   4 +
 port/log.c       | 175 +++++++++
 port/netif.c     |  31 +-
 port/netif.h     |   1 +
 port/parse.c     |  44 +++
 port/portdat.h   |  33 ++
 port/portfns.h   |   6 +
 16 files changed, 1877 insertions(+), 53 deletions(-)
 create mode 100644 ip/esp.c
 create mode 100644 port/devbridge.c
 create mode 100644 port/log.c
 create mode 100644 port/parse.c

diff --git a/boot/boot.c b/boot/boot.c
index 0d71ae2b422fd26546a2afca92bfefee5000ae2c..c755ee88641b7ada2f8869101fed5ca9a98aeabd 100644
--- a/boot/boot.c
+++ b/boot/boot.c
@@ -117,10 +117,14 @@ boot(int argc, char *argv[])
 	 */
 	if(bind("/", "/", MREPL) < 0)
 		fatal("bind /");
-	if(mount(fd, "/", MAFTER|MCREATE, "") < 0)
+	if(mount(fd, "/root", MREPL|MCREATE, "") < 0)
 		fatal("mount /");
+	if(bind(rootdir, "/", MAFTER|MCREATE) < 0)
+		fatal("bind /");
 	close(fd);
 
+	setenv("rootdir", rootdir);
+
 	/*
 	 *  if a local file server exists and it's not
 	 *  running, start it and mount it onto /n/kfs
diff --git a/boot/boot.h b/boot/boot.h
index decf26b32fc3017f13c6be86277876a534b6f26c..1ca7b9e48676b136700b978749e2c9b2f3bd60dd 100644
--- a/boot/boot.h
+++ b/boot/boot.h
@@ -9,6 +9,7 @@ struct Method
 };
 
 extern char*	bootdisk;
+extern char*	rootdir;
 extern int	(*cfs)(int);
 extern int	cpuflag;
 extern char	cputype[];
diff --git a/ip/devip.c b/ip/devip.c
index f03fb89342c578f3fcbddeb63836a34975a3722a..c7606c4c145e3c9609643d9d3ec30261f37b2269 100644
--- a/ip/devip.c
+++ b/ip/devip.c
@@ -565,8 +565,13 @@ ipread(Chan *ch, void *a, long n, vlong off)
 		return rv;
 	case Qremote:
 		buf = smalloc(Statelen);
-		c = f->p[PROTO(ch->qid)]->conv[CONV(ch->qid)];
-		sprint(buf, "%I!%d\n", c->raddr, c->rport);
+		x = f->p[PROTO(ch->qid)];
+		c = x->conv[CONV(ch->qid)];
+		if(x->remote == nil) {
+			sprint(buf, "%I!%d\n", c->raddr, c->rport);
+		} else {
+			(*x->remote)(c, buf, Statelen-2);
+		}
 		rv = readstr(offset, p, n, buf);
 		free(buf);
 		return rv;
@@ -905,6 +910,8 @@ ipwrite(Chan* ch, char* a, long n, vlong)
 			free(cb);
 			nexterror();
 		}
+		if(cb->nf < 1)
+			error("short control request");
 		if(strcmp(cb->f[0], "connect") == 0)
 			connectctlmsg(x, c, cb);
 		else if(strcmp(cb->f[0], "announce") == 0)
diff --git a/ip/esp.c b/ip/esp.c
new file mode 100644
index 0000000000000000000000000000000000000000..1d86773cafeba716120880b1ace9ef709f2261fd
--- /dev/null
+++ b/ip/esp.c
@@ -0,0 +1,645 @@
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"../port/error.h"
+
+#include	"ip.h"
+
+#include	"libcrypt.h"
+
+typedef struct Esphdr Esphdr;
+typedef struct Esptail Esptail;
+typedef struct Userhdr Userhdr;
+typedef struct Esppriv Esppriv;
+typedef struct Espcb Espcb;
+typedef struct Algorithm Algorithm;
+
+#define DPRINT if(0)print
+
+enum
+{
+	IP_ESPPROTO	= 50,
+	EsphdrSize	= 28,	// includes IP header
+	IphdrSize	= 20,	// options have been striped
+	EsptailSize	= 2,	// does not include pad or auth data
+	UserhdrSize	= 4,	// user visable header size - if enabled
+};
+
+struct Esphdr
+{
+	/* ip header */
+	uchar	vihl;		/* Version and header length */
+	uchar	tos;		/* Type of service */
+	uchar	length[2];	/* packet length */
+	uchar	id[2];		/* Identification */
+	uchar	frag[2];	/* Fragment information */
+	uchar	Unused;	
+	uchar	espproto;	/* Protocol */
+	uchar	espplen[2];	/* Header plus data length */
+	uchar	espsrc[4];	/* Ip source */
+	uchar	espdst[4];	/* Ip destination */
+
+	/* esp header */
+	uchar	espspi[4];	/* Security parameter index */
+	uchar	espseq[4];	/* Sequence number */
+};
+
+struct Esptail
+{
+	uchar	pad;
+	uchar	nexthdr;
+};
+
+/* header as seen by the user */
+struct Userhdr
+{
+	uchar	nexthdr;	// next protocol
+	uchar	unused[3];
+};
+
+struct Esppriv
+{
+	ulong	in;
+	ulong	inerrors;
+};
+
+/*
+ *  protocol specific part of Conv
+ */
+struct Espcb
+{
+	int	incoming;
+	int	header;		// user user level header
+	ulong	spi;
+	ulong	seq;		// last seq sent
+	ulong	window;		// for replay attacks
+	char	*espalg;
+	void	*espstate;	// other state for esp
+	int	espivlen;	// in bytes
+	int	espblklen;
+	int	(*cipher)(Espcb*, uchar *buf, int len);
+	char	*ahalg;
+	void	*ahstate;	// other state for esp
+	int	ahlen;		// auth data length in bytes
+	int	ahblklen;
+	int	(*auth)(Espcb*, uchar *buf, int len, uchar *hash);
+};
+
+struct Algorithm
+{
+	char 	*name;
+	int	keylen;		// in bits
+	void	(*init)(Espcb*, char* name, uchar *key, int keylen);
+};
+
+static	Conv* convlookup(Proto *esp, ulong spi);
+static	char *setalg(Espcb *ecb, char **f, int n, Algorithm *alg);
+static	void nullespinit(Espcb*, char*, uchar *key, int keylen);
+static	void nullahinit(Espcb*, char*, uchar *key, int keylen);
+static	void desespinit(Espcb *ecb, char *name, uchar *k, int n);
+
+static Algorithm espalg[] =
+{
+	"null",			0,	nullespinit,
+	"des_56_cbc",		64,	desespinit,
+	nil,			0,	nil,
+};
+
+static Algorithm ahalg[] =
+{
+	"null",			0,	nullahinit,
+	nil,			0,	nil,
+};
+
+static char*
+espconnect(Conv *c, char **argv, int argc)
+{
+	char *p, *pp;
+	char *e = nil;
+	ulong spi;
+	Espcb *ecb = (Espcb*)c->ptcl;
+
+	qlock(c);
+	switch(argc) {
+	default:
+		e = "bad args to connect";
+		break;
+	case 2:
+		p = strchr(argv[1], '!');
+		if(p == nil){
+			e = "malformed address";
+			break;
+		}
+		*p++ = 0;
+		parseip(c->raddr, argv[1]);
+		findlocalip(c->p->f, c->laddr, c->raddr);
+		ecb->incoming = 0;
+		ecb->seq = 0;
+		if(strcmp(p, "*") == 0) {
+			qlock(c->p);
+			for(;;) {
+				spi = nrand(1<<16) + 256;
+				if(convlookup(c->p, spi) == nil)
+					break;
+			}
+			qunlock(c->p);
+			ecb->spi = spi;
+			ecb->incoming = 1;
+			qhangup(c->wq, nil);
+		} else {
+			spi = strtoul(p, &pp, 10);
+			if(pp == p) {
+				e = "malformed address";
+				break;
+			}
+			ecb->spi = spi;
+			qhangup(c->rq, nil);
+		}
+		nullespinit(ecb, "null", nil, 0);
+		nullahinit(ecb, "null", nil, 0);
+	}
+	qunlock(c);
+	Fsconnected(c, e);
+
+	return e;
+}
+
+
+static int
+espstate(Conv *c, char *state, int n)
+{
+	return snprint(state, n, "%s", c->inuse?"Open\n":"Closed\n");
+}
+
+static void
+espcreate(Conv *c)
+{
+	c->rq = qopen(64*1024, 1, 0, 0);
+	c->wq = qopen(64*1024, 0, 0, 0);
+}
+
+static void
+espclose(Conv *c)
+{
+	Espcb *ecb;
+
+	qclose(c->rq);
+	qclose(c->wq);
+	qclose(c->eq);
+	ipmove(c->laddr, IPnoaddr);
+	ipmove(c->raddr, IPnoaddr);
+
+	ecb = (Espcb*)c->ptcl;
+	free(ecb->espstate);
+	free(ecb->ahstate);
+	memset(ecb, 0, sizeof(Espcb));
+	
+	qunlock(c);
+}
+
+void
+espkick(Conv *c, int)
+{
+	Esphdr *eh;
+	Esptail *et;
+	Userhdr *uh;
+	Espcb *ecb;
+	Block *bp;
+	int nexthdr;
+	int payload;
+	int pad;
+	int align;
+	uchar *auth;
+
+	bp = qget(c->wq);
+	if(bp == nil)
+		return;
+
+	qlock(c);
+	ecb = c->ptcl;
+
+	if(ecb->header) {
+		/* make sure the message has a User header */
+		bp = pullupblock(bp, UserhdrSize);
+		if(bp == nil) {
+			qunlock(c);
+			return;
+		}
+		uh = (Userhdr*)bp->rp;
+		nexthdr = uh->nexthdr;
+		bp->rp += UserhdrSize;
+	} else {
+		nexthdr = 0;  // what should this be?
+	}
+
+	payload = BLEN(bp) + ecb->espivlen;
+
+	/* Make space to fit ip header */
+	bp = padblock(bp, EsphdrSize + ecb->espivlen);
+
+	align = 4;
+	if(ecb->espblklen > align)
+		align = ecb->espblklen;
+	if(align % ecb->ahblklen != 0)
+		panic("espkick: ahblklen is important after all");
+	pad = (align-1) - (payload + EsptailSize-1)%align;
+
+	/*
+	 * Make space for tail
+	 * this is done by calling padblock with a negative size
+	 * Padblock does not change bp->wp!
+	 */
+	bp = padblock(bp, -(pad+EsptailSize+ecb->ahlen));
+	bp->wp += pad+EsptailSize+ecb->ahlen;
+
+	eh = (Esphdr *)(bp->rp);
+	et = (Esptail*)(bp->rp + EsphdrSize + payload + pad);
+
+	// fill in tail
+	et->pad = pad;
+	et->nexthdr = nexthdr;
+
+	ecb->cipher(ecb, bp->rp+EsphdrSize, payload+pad+EsptailSize);
+	auth = bp->rp + EsphdrSize + payload + pad + EsptailSize;
+	ecb->auth(ecb, bp->rp+IphdrSize, (EsphdrSize-IphdrSize)+payload+pad+EsptailSize, auth);
+
+	// fill in head
+	hnputl(eh->espspi, ecb->spi);
+	hnputl(eh->espseq, ++ecb->seq);
+	v6tov4(eh->espsrc, c->laddr);
+	v6tov4(eh->espdst, c->raddr);
+	eh->espproto = IP_ESPPROTO;
+	eh->frag[0] = 0;
+	eh->frag[1] = 0;
+
+	qunlock(c);
+//print("esp: pass down: %uld\n", BLEN(bp));
+	ipoput(c->p->f, bp, 0, c->ttl);
+}
+
+void
+espiput(Proto *esp, uchar*, Block *bp)
+{
+	Esphdr *eh;
+	Esptail *et;
+	Userhdr *uh;
+	Conv *c;
+	Espcb *ecb;
+	uchar raddr[IPaddrlen], laddr[IPaddrlen];
+	Fs *f;
+	uchar *auth;
+	ulong spi;
+	int payload, nexthdr;
+
+	f = esp->f;
+
+	bp = pullupblock(bp, EsphdrSize+EsptailSize);
+	if(bp == nil) {
+		netlog(f, Logesp, "esp: short packet\n");
+		return;
+	}
+
+	eh = (Esphdr*)(bp->rp);
+	spi = nhgetl(eh->espspi);
+	v4tov6(raddr, eh->espsrc);
+	v4tov6(laddr, eh->espdst);
+
+	qlock(esp);
+	/* Look for a conversation structure for this port */
+	c = convlookup(esp, spi);
+	if(c == nil) {
+		qunlock(esp);
+		netlog(f, Logesp, "esp: no conv %I -> %I!%d\n", raddr,
+			laddr, spi);
+		icmpnoconv(f, bp);
+		freeblist(bp);
+		return;
+	}
+
+	qlock(c);
+	qunlock(esp);
+
+	ecb = c->ptcl;
+	// too hard to do decryption/authentication on block lists
+	if(bp->next)
+		bp = concatblock(bp);
+
+	if(BLEN(bp) < EsphdrSize + ecb->espivlen + EsptailSize + ecb->ahlen) {
+		qunlock(esp);
+		netlog(f, Logesp, "esp: short block %I -> %I!%d\n", raddr,
+			laddr, spi);
+		freeb(bp);
+		return;
+	}
+
+	eh = (Esphdr*)(bp->rp);
+	auth = bp->wp - ecb->ahlen;
+	if(!ecb->auth(ecb, eh->espspi, auth-eh->espspi, auth)) {
+		qunlock(esp);
+		netlog(f, Logesp, "esp: bad auth %I -> %I!%d\n", raddr,
+			laddr, spi);
+		freeb(bp);
+		return;
+	}
+
+	payload = BLEN(bp)-EsphdrSize-ecb->ahlen;
+	if(payload<=0 || payload%4 != 0 || payload%ecb->espblklen!=0) {
+		qunlock(esp);
+		netlog(f, Logesp, "esp: bad length %I -> %I!%d payload=%d BLEN=%d\n", raddr,
+			laddr, spi, payload, BLEN(bp));
+		freeb(bp);
+		return;
+	}
+	ecb->cipher(ecb, bp->rp+EsphdrSize, payload);
+
+	payload -= EsptailSize;
+	et = (Esptail*)(bp->rp + EsphdrSize + payload);
+	payload -= et->pad + ecb->espivlen;
+	nexthdr = et->nexthdr;
+	if(payload <= 0) {
+		qunlock(esp);
+		netlog(f, Logesp, "esp: short packet after decrypt %I -> %I!%d\n", raddr,
+			laddr, spi);
+		freeb(bp);
+		return;
+	}
+
+	// trim packet
+	bp->rp += EsphdrSize + ecb->espivlen;
+	bp->wp = bp->rp + payload;
+	if(ecb->header) {
+		// assume UserhdrSize < EsphdrSize
+		bp->rp -= UserhdrSize;
+		uh = (Userhdr*)bp->rp;
+		memset(uh, 0, UserhdrSize);
+		uh->nexthdr = nexthdr;
+	}
+
+	if(qfull(c->rq)){
+		netlog(f, Logesp, "esp: qfull %I -> %I.%uld\n", raddr,
+			laddr, spi);
+		freeblist(bp);
+	}else {
+//print("esp: pass up: %uld\n", BLEN(bp));
+		qpass(c->rq, bp);
+	}
+
+	qunlock(c);
+}
+
+char*
+espctl(Conv *c, char **f, int n)
+{
+	Espcb *ecb = c->ptcl;
+	char *e = nil;
+
+	qlock(c);
+	if(strcmp(f[0], "esp") == 0)
+		e = setalg(ecb, f, n, espalg);
+	else if(strcmp(f[0], "ah") == 0)
+		e = setalg(ecb, f, n, ahalg);
+	else if(strcmp(f[0], "header") == 0)
+		ecb->header = 1;
+	else if(strcmp(f[0], "noheader") == 0)
+		ecb->header = 0;
+	else
+		e = "unknown control request";
+	qunlock(c);
+	return e;
+}
+
+void
+espadvise(Proto *esp, Block *bp, char *msg)
+{
+	Esphdr *h;
+	Conv *c;
+	ulong spi;
+
+	h = (Esphdr*)(bp->rp);
+
+	spi = nhgets(h->espspi);
+	qlock(esp);
+	c = convlookup(esp, spi);
+	if(c != nil) {
+		qhangup(c->rq, msg);
+		qhangup(c->wq, msg);
+	}
+	qunlock(esp);
+	freeblist(bp);
+}
+
+int
+espstats(Proto *esp, char *buf, int len)
+{
+	Esppriv *upriv;
+
+	upriv = esp->priv;
+	return snprint(buf, len, "%lud %lud\n",
+		upriv->in,
+		upriv->inerrors);
+}
+
+static int
+esplocal(Conv *c, char *buf, int len)
+{
+	Espcb *ecb = c->ptcl;
+	int n;
+
+	qlock(c);
+	if(ecb->incoming)
+		n = snprint(buf, len, "%I!%uld\n", c->laddr, ecb->spi);
+	else
+		n = snprint(buf, len, "%I\n", c->laddr);
+	qunlock(c);
+	return n;
+}
+
+static int
+espremote(Conv *c, char *buf, int len)
+{
+	Espcb *ecb = c->ptcl;
+	int n;
+
+	qlock(c);
+	if(ecb->incoming)
+		n = snprint(buf, len, "%I\n", c->raddr);
+	else
+		n = snprint(buf, len, "%I!%uld\n", c->raddr, ecb->spi);
+	qunlock(c);
+	return n;
+}
+
+// should have esp locked
+static	Conv*
+convlookup(Proto *esp, ulong spi)
+{
+	Conv *c, **p;
+	Espcb *ecb;
+
+	for(p=esp->conv; *p; p++){
+		c = *p;
+		ecb = c->ptcl;
+		if(ecb->incoming && ecb->spi == spi)
+			return c;
+	}
+}
+
+static char *
+setalg(Espcb *ecb, char **f, int n, Algorithm *alg)
+{
+	uchar *key;
+	int i, nbyte, nchar;
+	int c;
+
+	if(n < 2)
+		return "bad format";
+	for(; alg->name; alg++)
+		if(strcmp(f[1], alg->name) == 0)
+			break;
+	if(alg->name == nil)
+		return "unknown algorithm";
+
+	if(n != 3)
+		return "bad format";
+	nbyte = (alg->keylen + 7) >> 3;
+	nchar = strlen(f[2]);
+	for(i=0; i<nchar; i++) {
+		c = f[2][i];
+		if(c >= '0' && c <= '9')
+			f[2][i] -= '0';
+		else if(c >= 'a' && c <= 'f')
+			f[2][i] -= 'a'-10;
+		else if(c >= 'A' && c <= 'F')
+			f[2][i] -= 'A'-10;
+		else
+			return "bad character in key";
+	}
+	key = smalloc(nbyte);
+	for(i=0; i<nchar && i*2<nbyte; i++) {
+		c = f[2][nchar-i-1];
+		if(i&1)
+			c <<= 4;
+		key[i>>1] |= c;
+	}
+
+	alg->init(ecb, alg->name, key, alg->keylen);
+	free(key);
+	return nil;
+}
+
+static int
+nullcipher(Espcb*, uchar*, int)
+{
+	return 1;
+}
+
+static void
+nullespinit(Espcb *ecb, char *name, uchar*, int)
+{
+	ecb->espalg = name;
+	ecb->espblklen = 1;
+	ecb->espivlen = 0;
+	ecb->cipher = nullcipher;
+}
+
+static int
+nullauth(Espcb*, uchar*, int, uchar*)
+{
+	return 1;
+}
+
+static void
+nullahinit(Espcb *ecb, char *name, uchar*, int)
+{
+	ecb->ahalg = name;
+	ecb->ahblklen = 1;
+	ecb->ahlen = 0;
+	ecb->auth = nullauth;
+}
+
+static int
+descipher(Espcb *ecb, uchar *p, int n)
+{
+	uchar tmp[8];
+	uchar *pp, *tp, *ip, *eip, *ep;
+	DESstate *ds = ecb->espstate;
+
+	ep = p + n;
+	if(ecb->incoming) {
+		memmove(ds->ivec, p, 8);
+		p += 8;
+		while(p < ep){
+			memmove(tmp, p, 8);
+			block_cipher(ds->expanded, p, 1);
+			tp = tmp;
+			ip = ds->ivec;
+			for(eip = ip+8; ip < eip; ){
+				*p++ ^= *ip;
+				*ip++ = *tp++;
+			}
+		}
+	} else {
+		memmove(p, ds->ivec, 8);
+		for(p += 8; p < ep; p += 8){
+			pp = p;
+			ip = ds->ivec;
+			for(eip = ip+8; ip < eip; )
+				*pp++ ^= *ip++;
+			block_cipher(ds->expanded, p, 0);
+			memmove(ds->ivec, p, 8);
+		}
+	}
+	return 1;
+}
+	
+static void
+desespinit(Espcb *ecb, char *name, uchar *k, int n)
+{
+	uchar key[8];
+	uchar ivec[8];
+	int i;
+	
+	// bits to bytes
+	n = (n+7)>>3;
+	if(n > 8)
+		n = 8;
+	memset(key, 0, sizeof(key));
+	memmove(key, k, n);
+	for(i=0; i<8; i++)
+		ivec[i] = nrand(256);
+	ecb->espalg = name;
+	ecb->espblklen = 8;
+	ecb->espivlen = 8;
+	ecb->cipher = descipher;
+	ecb->espstate = smalloc(sizeof(DESstate));
+	setupDESstate(ecb->espstate, key, ivec);
+}
+	
+void
+espinit(Fs *fs)
+{
+	Proto *esp;
+
+	esp = smalloc(sizeof(Proto));
+	esp->priv = smalloc(sizeof(Esppriv));
+	esp->name = "esp";
+	esp->kick = espkick;
+	esp->connect = espconnect;
+	esp->announce = nil;
+	esp->ctl = espctl;
+	esp->state = espstate;
+	esp->create = espcreate;
+	esp->close = espclose;
+	esp->rcv = espiput;
+	esp->advise = espadvise;
+	esp->stats = espstats;
+	esp->local = esplocal;
+	esp->remote = espremote;
+	esp->ipproto = IP_ESPPROTO;
+	esp->nc = Nchans;
+	esp->ptclsize = sizeof(Espcb);
+
+	Fsproto(fs, esp);
+}
diff --git a/ip/ip.h b/ip/ip.h
index d5dc298d13a6053f9737fc035fcc1ffc43c76972..2d07ad2a3a956468f8c9e4699295a3767ed6a3e7 100644
--- a/ip/ip.h
+++ b/ip/ip.h
@@ -11,7 +11,7 @@ typedef struct	Ipmulti	Ipmulti;
 typedef struct	Ipmux	Ipmux;
 typedef struct	IProuter IProuter;
 typedef struct	Ipifc	Ipifc;
-typedef struct	Log	Log;
+typedef struct	Netlog	Netlog;
 typedef struct	Ifclog	Ifclog;
 typedef struct	Medium	Medium;
 typedef struct	Proto	Proto;
@@ -212,6 +212,7 @@ struct Proto
 	void		(*advise)(Proto*, Block*, char*);
 	int		(*stats)(Proto*, char*, int);
 	int		(*local)(Conv*, char*, int);
+	int		(*remote)(Conv*, char*, int);
 	int		(*inuse)(Conv*);
 
 	Fs		*f;		/* file system this proto is part of */
@@ -258,7 +259,7 @@ struct Fs
 	Route	*v6root[1<<Lroot];	/* v6 routing forest */
 	Route	*queue;			/* used as temp when reinjecting routes */
 
-	Log	*alog;
+	Netlog	*alog;
 	Ifclog	*ilog;
 };
 
@@ -295,7 +296,7 @@ enum
 	Logipmsg=	1<<14,
 	Logrudp=	1<<15,
 	Logrudpmsg=	1<<16,
-
+	Logesp=		1<<17,
 };
 
 void	netloginit(Fs*);
@@ -415,14 +416,6 @@ extern void	arpenter(Fs*, int version, uchar *ip, uchar *mac, int len, int noref
  * ipaux.c
  */
 
-typedef struct Cmdbuf	Cmdbuf;
-struct Cmdbuf
-{
-	char	buf[64];
-	char	*f[16];
-	int	nf;
-};
-
 extern int	myetheraddr(uchar*, char*);
 extern ulong	parseip(uchar*, char*);
 extern ulong	parseipmask(uchar*, char*);
@@ -433,7 +426,6 @@ extern uchar*	defmask(uchar*);
 extern int	isv4(uchar*);
 extern void	v4tov6(uchar *v6, uchar *v4);
 extern int	v6tov4(uchar *v4, uchar *v6);
-extern Cmdbuf*	parsecmd(char *a, int n);
 extern int	eipconv(va_list *arg, Fconv *f);
 
 #define	ipcmp(x, y) memcmp(x, y, IPaddrlen)
@@ -498,7 +490,6 @@ extern void	(*ipextprotoiput)(Block*);
 extern void	ipiput(Fs*, uchar*, Block*);
 extern void	ipoput(Fs*, Block*, int, int);
 extern int	ipstats(Fs*, char*, int);
-extern uchar*	logctl(uchar*);
 extern ushort	ptclbsum(uchar*, int);
 extern ushort	ptclcsum(Block*, int, int);
 extern void	ip_init(Fs*);
diff --git a/ip/ipaux.c b/ip/ipaux.c
index 75720ee9f65df15ed23dc8527a2ae16d95139d60..0e04b6ffdc6b8fd8ff2ddf0715e6a5159b15c8cb 100644
--- a/ip/ipaux.c
+++ b/ip/ipaux.c
@@ -360,26 +360,6 @@ defmask(uchar *ip)
 	return classmask[ip[IPv4off]>>6];
 }
 
-/*
- *  parse a command written to a device
- */
-Cmdbuf*
-parsecmd(char *p, int n)
-{
-	Cmdbuf *cb;
-
-	cb = smalloc(sizeof(*cb));
-	
-	if(n > sizeof(cb->buf)-1)
-		n = sizeof(cb->buf)-1;
-	memmove(cb->buf, p, n);
-	if(n > 0 && cb->buf[n-1] == '\n')
-		n--;
-	cb->buf[n] = '\0';
-	cb->nf = parsefields(cb->buf, cb->f, nelem(cb->f), " ");
-	return cb;
-}
-
 /*
  *  parse a hex mac address
  */
diff --git a/ip/netlog.c b/ip/netlog.c
index 19d0112d140dda0c23f96c5763937b1ca2c77984..473a6f82941874c65e2640a710acefcb9eb046be 100644
--- a/ip/netlog.c
+++ b/ip/netlog.c
@@ -13,7 +13,7 @@ enum {
 /*
  *  action log
  */
-struct Log {
+struct Netlog {
 	Lock;
 	int	opens;
 	char*	buf;
@@ -29,12 +29,12 @@ struct Log {
 	Rendez;
 };
 
-typedef struct Logflag {
+typedef struct Netlogflag {
 	char*	name;
 	int	mask;
-} Logflag;
+} Netlogflag;
 
-static Logflag flags[] =
+static Netlogflag flags[] =
 {
 	{ "ppp",	Logppp, },
 	{ "ip",		Logip, },
@@ -49,6 +49,7 @@ static Logflag flags[] =
 	{ "tcpmsg",	Logtcp|Logtcpmsg, },
 	{ "udpmsg",	Logudp|Logudpmsg, },
 	{ "ipmsg",	Logip|Logipmsg, },
+	{ "esp",	Logesp, },
 	{ nil,		0, },
 };
 
@@ -57,7 +58,7 @@ static char Ebadnetctl[] = "unknown netlog ctl message";
 void
 netloginit(Fs *f)
 {
-	f->alog = smalloc(sizeof(Log));
+	f->alog = smalloc(sizeof(Netlog));
 }
 
 void
@@ -158,7 +159,7 @@ char*
 netlogctl(Fs *f, char* s, int len)
 {
 	int i, n, set;
-	Logflag *fp;
+	Netlogflag *fp;
 	char *fields[10], *p, buf[256];
 
 	if(len == 0)
diff --git a/pc/devether.c b/pc/devether.c
index 3b574de585b4ce888aa90cd216f513dbaefa3032..2d679c9246afdadc1d1c1e0e00437e7e2c1666b3 100644
--- a/pc/devether.c
+++ b/pc/devether.c
@@ -134,7 +134,7 @@ etheriq(Ether* ether, Block* bp, int freebp)
 {
 	Etherpkt *pkt;
 	ushort type;
-	int len;
+	int len, multi, forme;
 	Netfile **ep, *f, **fp, *fx;
 	Block *xbp;
 
@@ -146,8 +146,9 @@ etheriq(Ether* ether, Block* bp, int freebp)
 	fx = 0;
 	ep = &ether->f[Ntypes];
 
+	multi = pkt->d[0] & 1;
 	/* check for valid multcast addresses */
-	if((pkt->d[0] & 1) && memcmp(pkt->d, ether->bcast, sizeof(pkt->d)) && ether->prom == 0){
+	if(multi && memcmp(pkt->d, ether->bcast, sizeof(pkt->d)) && ether->prom == 0){
 		if(!activemulti(ether, pkt->d, sizeof(pkt->d))){
 			if(freebp){
 				freeb(bp);
@@ -157,6 +158,9 @@ etheriq(Ether* ether, Block* bp, int freebp)
 		}
 	}
 
+	// is it for me?
+	forme = memcmp(pkt->d, ether->ea, sizeof(pkt->d)) == 0;
+
 	/*
 	 * Multiplex the packet to all the connections which want it.
 	 * If the packet is not to be used subsequently (freebp != 0),
@@ -164,7 +168,7 @@ etheriq(Ether* ether, Block* bp, int freebp)
 	 * saving a copy of the data (usual case hopefully).
 	 */
 	for(fp = ether->f; fp < ep; fp++){
-		if((f = *fp) && (f->type == type || f->type < 0)){
+		if((f = *fp) && (f->type == type || f->type < 0) && (forme || multi || f->prom)){
 			if(f->type > -2){
 				if(freebp && fx == 0)
 					fx = f;
@@ -197,7 +201,7 @@ etheriq(Ether* ether, Block* bp, int freebp)
 static int
 etheroq(Ether* ether, Block* bp)
 {
-	int len, loopback, s;
+	int len, loopback, s, mine;
 	Etherpkt *pkt;
 
 	ether->outpackets++;
@@ -208,10 +212,14 @@ etheroq(Ether* ether, Block* bp)
 	 * in promiscuous mode.
 	 * If it's a loopback packet indicate to etheriq that the data isn't
 	 * needed and return, etheriq will pass-on or free the block.
+	 * To enable bridging to work, only packets that were originated
+	 * by this interface are feedback
 	 */
 	pkt = (Etherpkt*)bp->rp;
 	len = BLEN(bp);
 	loopback = (memcmp(pkt->d, ether->ea, sizeof(pkt->d)) == 0);
+	mine = memcmp(pkt->s, ether->ea, sizeof(pkt->s)) == 0;
+	if(mine)
 	if(loopback || memcmp(pkt->d, ether->bcast, sizeof(pkt->d)) == 0 || ether->prom){
 		s = splhi();
 		etheriq(ether, bp, loopback);
diff --git a/port/devbridge.c b/port/devbridge.c
new file mode 100644
index 0000000000000000000000000000000000000000..4be66a3fec588ee01a458e2cd91c2536ead99e91
--- /dev/null
+++ b/port/devbridge.c
@@ -0,0 +1,907 @@
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "../port/netif.h"
+#include "../port/error.h"
+
+typedef struct Bridge 	Bridge;
+typedef struct Port 	Port;
+typedef struct Centry	Centry;
+
+enum
+{
+	Qtopdir=	1,		/* top level directory */
+
+	Qbridgedir,			/* bridge* directory */
+	Qbctl,
+	Qstats,
+	Qcache,
+	Qlog,
+
+	Qportdir,			/* directory for a protocol */
+	Qpctl,
+	Qlocal,
+	Qstatus,
+
+	MaxQ,
+
+	Maxbridge=	4,
+	Maxport=	16,		// power of 2
+	CacheHash=	257,		// prime
+	CacheLook=	5,		// how many cache entries to examine
+	CacheSize=	(CacheHash+CacheLook-1),
+	CacheTimeout=	5*60,		// timeout for cache entry in seconds
+
+	Addrlen=	16,		// must be long enough of IP addr and ether addr
+};
+
+Dirtab bridgedirtab[]={
+	"ctl",		{Qbctl},	0,	0666,
+	"stats",	{Qstats},	0,	0444,
+	"cache",	{Qcache},	0,	0444,
+	"log",		{Qlog},		0,	0666,
+};
+
+Dirtab portdirtab[]={
+	"ctl",		{Qpctl},	0,	0666,
+	"local",	{Qlocal},	0,	0444,
+	"status",	{Qstatus},	0,	0444,
+};
+
+enum {
+	Logcache=	(1<<0),
+	Logmcast=	(1<<1),
+};
+
+// types of interfaces
+enum
+{
+	Tether,
+	Ttunnel,
+};
+
+static Logflag logflags[] =
+{
+	{ "cache",	Logcache, },
+	{ "multicast",	Logmcast, },
+	{ nil,		0, },
+};
+
+static Dirtab	*dirtab[MaxQ];
+
+#define TYPE(x) 	((x).path & 0xff)
+#define PORT(x) 	(((x).path >> 8)&(Maxport-1))
+#define QID(x, y) 	(((x)<<8) | (y))
+
+struct Centry
+{
+	uchar	d[Eaddrlen];
+	int	port;
+	long	expire;		// entry expires this number of seconds after bootime
+	long	src;
+	long	dst;
+};
+
+struct Bridge
+{
+	QLock;
+	int	nport;
+	Port	*port[Maxport];
+	Centry	cache[CacheSize];
+	int	hit;
+	int	miss;
+
+	Log;
+};
+
+struct Port
+{
+	int	id;
+	Bridge	*bridge;
+	int	ref;
+	int	closed;
+
+	Chan	*data[2];	// channel to data
+
+	int	mcast;		// send multi cast packets
+	Proc	*readp;		// read proc
+	
+	// the following uniquely identifies the port
+	int	type;
+	uchar	addr[Addrlen];
+	
+	// owner hash - avoids bind/unbind races
+	ulong	ownhash;
+
+	// various stats
+	int	in;		// number of packets read
+	int	inmulti;	// multicast or broadcast
+	int	inunknown;	// unknown address
+	int	out;		// number of packets read
+	int	outmulti;	// multicast or broadcast
+	int	outunknown;	// unknown address
+	int	nentry;		// number of cache entries for this port
+};
+
+static Bridge bridgetab[Maxbridge];
+
+static int m2p[] = {
+	[OREAD]		4,
+	[OWRITE]	2,
+	[ORDWR]		6
+};
+
+static int	bridgegen(Chan *c, Dirtab*, int, int s, Dir *dp);
+static void	portbind(Bridge *b, int argc, char *argv[]);
+static void	portunbind(Bridge *b, int argc, char *argv[]);
+static void	etherread(void *a);
+static char	*cachedump(Bridge *b);
+static void	portfree(Port *port);
+static void	cacheflushport(Bridge *b, int port);
+
+extern ulong	parseip(uchar*, char*);
+
+static void
+bridgeinit(void)
+{
+	int i;
+	Dirtab *dt;
+	// setup dirtab with non directory entries
+	for(i=0; i<nelem(bridgedirtab); i++) {
+		dt = bridgedirtab + i;
+		dirtab[TYPE(dt->qid)] = dt;
+	}
+	for(i=0; i<nelem(portdirtab); i++) {
+		dt = portdirtab + i;
+		dirtab[TYPE(dt->qid)] = dt;
+	}
+}
+
+static Chan*
+bridgeattach(char* spec)
+{
+	Chan *c;
+	int dev;
+
+	dev = atoi(spec);
+	if(dev<0 || dev >= Maxbridge)
+		error("bad specification");
+
+	c = devattach('B', spec);
+	c->qid = (Qid){QID(0, Qtopdir)|CHDIR, 0};
+	c->dev = dev;
+
+	return c;
+}
+
+static int
+bridgewalk(Chan *c, char *name)
+{
+	Path *op;
+
+	if(strcmp(name, "..") == 0){
+		switch(TYPE(c->qid)){
+		case Qtopdir:
+		case Qbridgedir:
+			c->qid = (Qid){CHDIR|Qtopdir, 0};
+			break;
+		case Qportdir:
+			c->qid = (Qid){CHDIR|Qbridgedir, 0};
+			break;
+		default:
+			panic("bridgewalk %lux", c->qid.path);
+		}
+		op = c->path;
+		c->path = ptenter(&syspt, op, name);
+		decref(op);
+		return 1;
+	}
+
+	return devwalk(c, name, 0, 0, bridgegen);
+}
+
+static void
+bridgestat(Chan* c, char* db)
+{
+	devstat(c, db, nil, 0, bridgegen);
+}
+
+static Chan*
+bridgeopen(Chan* c, int omode)
+{
+	int perm;
+	Bridge *b;
+
+	omode &= 3;
+	perm = m2p[omode];
+	USED(perm);
+
+	b = bridgetab + c->dev;
+	USED(b);
+
+	switch(TYPE(c->qid)) {
+	default:
+		break;
+	case Qtopdir:
+	case Qbridgedir:
+	case Qportdir:
+	case Qstatus:
+	case Qlocal:
+	case Qstats:
+		if(omode != OREAD)
+			error(Eperm);
+		break;
+	case Qlog:
+		logopen(b);
+		break;
+	case Qcache:
+		if(omode != OREAD)
+			error(Eperm);
+		c->aux = cachedump(b);
+		break;
+	}
+	c->mode = openmode(omode);
+	c->flag |= COPEN;
+	c->offset = 0;
+	return c;
+}
+
+static void
+bridgeclose(Chan* c)
+{
+	Bridge *b  = bridgetab + c->dev;
+
+	switch(TYPE(c->qid)) {
+	case Qcache:
+		if(c->flag & COPEN)
+			free(c->aux);
+		break;
+	case Qlog:
+		if(c->flag & COPEN)
+			logclose(b);
+		break;
+	}
+}
+
+static long
+bridgeread(Chan *c, void *a, long n, vlong off)
+{
+	char buf[256];
+	Bridge *b = bridgetab + c->dev;
+	Port *port;
+	int i;
+
+	USED(off);
+	switch(TYPE(c->qid)) {
+	default:
+		error(Eperm);
+	case Qtopdir:
+	case Qbridgedir:
+	case Qportdir:
+		return devdirread(c, a, n, 0, 0, bridgegen);
+	case Qlog:
+		return logread(b, a, off, n);
+	case Qstatus:
+		qlock(b);
+		port = b->port[PORT(c->qid)];
+		if(port == 0)
+			strcpy(buf, "unbound\n");
+		else {
+			i = 0;
+			switch(port->type) {
+			default: panic("bridgeread: unknown port type: %d", port->type);
+			case Tether:
+				i += snprint(buf+i, sizeof(buf)-i, "ether %E: ", port->addr);
+				break;
+			case Ttunnel:
+				i += snprint(buf+i, sizeof(buf)-i, "tunnel %I: ", port->addr);
+				break;
+			}
+			i += snprint(buf+i, sizeof(buf)-i, "in=%d/%d/%d out=%d/%d/%d\n",
+				port->in, port->inmulti, port->inunknown,
+				port->out, port->outmulti, port->outunknown);
+			USED(i);
+		}
+		n = readstr(off, a, n, buf);
+		qunlock(b);
+		return n;
+	case Qcache:
+		n = readstr(off, a, n, c->aux);
+		return n;
+	}
+}
+
+static long
+bridgewrite(Chan *c, void *a, long n, vlong off)
+{
+	Bridge *b = bridgetab + c->dev;
+	Cmdbuf *cb;
+	char *arg0;
+	char *p;
+	
+	USED(off);
+
+	switch(TYPE(c->qid)) {
+	default:
+		error(Eperm);
+	case Qbctl:
+		cb = parsecmd(a, n);
+		qlock(b);
+		if(waserror()) {
+			qunlock(b);
+			free(cb);
+			nexterror();
+		}
+		if(cb->nf == 0)
+			error("short write");
+		arg0 = cb->f[0];
+		if(strcmp(arg0, "bind") == 0)
+			portbind(b, cb->nf-1, cb->f+1);
+		else if(strcmp(arg0, "unbind") == 0)
+			portunbind(b, cb->nf-1, cb->f+1);
+		else if(strcmp(arg0, "cacheflush") == 0) {
+			log(b, Logcache, "cache flush\n");
+			memset(b->cache, 0, CacheSize*sizeof(Centry));
+		} else
+			error("unknown control request");
+		poperror();
+		qunlock(b);
+		free(cb);
+		return n;
+	case Qlog:
+		cb = parsecmd(a, n);
+		p = logctl(b, cb->nf, cb->f, logflags);
+		free(cb);
+		if(p != nil)
+			error(p);
+		return n;
+	}
+}
+
+static int
+bridgegen(Chan *c, Dirtab*, int, int s, Dir *dp)
+{
+	Bridge *b = bridgetab + c->dev;
+	int type = TYPE(c->qid);
+	char buf[32];
+	Dirtab *dt;
+	Qid qid;
+
+	switch(type) {
+	default:
+		// non directory entries end up here
+		if(c->qid.path & CHDIR)
+			panic("bridgegen: unexpected directory");	
+		if(s != 0)
+			return -1;
+		dt = dirtab[TYPE(c->qid)];
+		if(dt == nil)
+			panic("bridgegen: unknown type: %d", TYPE(c->qid));
+		devdir(c, c->qid, dt->name, dt->length, eve, dt->perm, dp);
+		return 1;
+	case Qtopdir:
+		if(s != 0)
+			return -1;
+		sprint(buf, "bridge%ld", c->dev);
+		devdir(c, (Qid){QID(0,Qbridgedir)|CHDIR,0}, buf, 0, eve, 0555, dp);
+		return 1;
+	case Qbridgedir:
+		if(s<nelem(bridgedirtab)) {
+			dt = bridgedirtab+s;
+			devdir(c, dt->qid, dt->name, dt->length, eve, dt->perm, dp);
+			return 1;
+		}
+		s -= nelem(bridgedirtab);
+		if(s >= b->nport)
+			return -1;
+		qid = (Qid){QID(s,Qportdir)|CHDIR, 0};
+		snprint(buf, sizeof(buf), "%d", s);
+		devdir(c, qid, buf, 0, eve, 0555, dp);
+		return 1;
+	case Qportdir:
+		if(s>=nelem(portdirtab))
+			return -1;
+		dt = portdirtab+s;
+		qid = (Qid){QID(PORT(c->qid),TYPE(dt->qid)),0};
+		devdir(c, qid, dt->name, dt->length, eve, dt->perm, dp);
+		return 1;
+	}
+}
+
+// also in netif.c
+static int
+parseaddr(uchar *to, char *from, int alen)
+{
+	char nip[4];
+	char *p;
+	int i;
+
+	p = from;
+	for(i = 0; i < alen; i++){
+		if(*p == 0)
+			return -1;
+		nip[0] = *p++;
+		if(*p == 0)
+			return -1;
+		nip[1] = *p++;
+		nip[2] = 0;
+		to[i] = strtoul(nip, 0, 16);
+		if(*p == ':')
+			p++;
+	}
+	return 0;
+}
+
+// assumes b is locked
+static void
+portbind(Bridge *b, int argc, char *argv[])
+{
+	Port *port;
+	char path[8*NAMELEN];
+	char buf[100];
+	char *dev, *dev2=nil, *p;
+	Chan *ctl;
+	int type=0, i, n;
+	char *usage = "usage: bind ether|tunnel addr ownhash dev [dev2]";
+	uchar addr[Addrlen];
+	ulong ownhash;
+
+	memset(addr, 0, Addrlen);
+	if(argc < 4)
+		error(usage);
+	if(strcmp(argv[0], "ether") == 0) {
+		if(argc != 4)
+			error(usage);
+		type = Tether;
+		parseaddr(addr, argv[1], Eaddrlen);
+	} else if(strcmp(argv[0], "tunnel") == 0) {
+		if(argc != 5)
+			error(usage);
+		type = Ttunnel;
+		parseip(addr, argv[1]);
+		dev2 = argv[4];
+	} else
+		error(usage);
+	ownhash = atoi(argv[2]);
+	dev = argv[3];
+	for(i=0; i<b->nport; i++) {
+		port = b->port[i];
+		if(port != nil)
+		if(port->type == type)
+		if(memcmp(port->addr, addr, Addrlen) == 0)
+			error("port in use");
+	}
+	for(i=0; i<Maxport; i++)
+		if(b->port[i] == nil)
+			break;
+	if(i == Maxport)
+		error("no more ports");
+	port = smalloc(sizeof(Port));
+	port->ref = 1;
+	port->id = i;
+	port->ownhash = ownhash;
+
+	if(waserror()) {
+		portfree(port);
+		nexterror();
+	}
+
+	port->type = type;
+	memmove(port->addr, addr, Addrlen);
+	switch(port->type) {
+	default: panic("portbind: unknown port type: %d", type);
+	case Tether:
+		snprint(path, sizeof(path), "%s/clone", dev);
+		ctl = namec(path, Aopen, ORDWR, 0);
+		if(waserror()) {
+			cclose(ctl);
+			nexterror();
+		}
+		// check addr?
+
+		// get directory name
+		n = devtab[ctl->type]->read(ctl, buf, sizeof(buf), 0);
+		buf[n] = 0;
+		for(p = buf; *p == ' '; p++)
+			;
+		snprint(path, sizeof(path), "%s/%lud/data", dev, strtoul(p, 0, 0));
+
+		// setup connection to be promiscuous
+		snprint(buf, sizeof(buf), "connect -1");
+		devtab[ctl->type]->write(ctl, buf, strlen(buf), 0);
+		snprint(buf, sizeof(buf), "promiscuous");
+		devtab[ctl->type]->write(ctl, buf, strlen(buf), 0);
+
+		// open data port
+		port->data[0] = namec(path, Aopen, ORDWR, 0);
+		// dup it
+		incref(port->data[0]);
+		port->data[1] = port->data[0];
+
+		poperror();
+		cclose(ctl);		
+
+		break;
+	case Ttunnel:
+		port->data[0] = namec(dev, Aopen, OREAD, 0);
+		port->data[1] = namec(dev2, Aopen, OWRITE, 0);
+		break;
+	}
+
+	poperror();
+
+	// commited to binding port
+	b->port[port->id] = port;
+	port->bridge = b;
+	if(b->nport <= port->id)
+		b->nport = port->id+1;
+
+	// assumes kproc always succeeds
+	port->ref++;
+	kproc("etherread", etherread, port);	// poperror must be next
+}
+
+// assumes b is locked
+static void
+portunbind(Bridge *b, int argc, char *argv[])
+{
+	Port *port=nil;
+	int type=0, i;
+	char *usage = "usage: unbind ether|tunnel addr [ownhash]";
+	uchar addr[Addrlen];
+	ulong ownhash;
+
+	memset(addr, 0, Addrlen);
+	if(argc < 2 || argc > 3)
+		error(usage);
+	if(strcmp(argv[0], "ether") == 0) {
+		type = Tether;
+		parseaddr(addr, argv[1], Eaddrlen);
+	} else if(strcmp(argv[0], "tunnel") == 0) {
+		type = Ttunnel;
+		parseip(addr, argv[1]);
+	} else
+		error(usage);
+	if(argc == 3)
+		ownhash = atoi(argv[2]);
+	else
+		ownhash = 0;
+	for(i=0; i<b->nport; i++) {
+		port = b->port[i];
+		if(port != nil)
+		if(port->type == type)
+		if(memcmp(port->addr, addr, Addrlen) == 0)
+			break;
+	}
+	if(i == b->nport)
+		error("port not found");
+	if(ownhash != 0 && port->ownhash != 0 && ownhash != port->ownhash)
+		error("bad owner hash");
+
+	port->closed = 1;
+	b->port[i] = nil;	// port is now unbound
+	cacheflushport(b, i);
+
+	// try and stop reader
+	if(port->readp)
+		postnote(port->readp, 1, "unbind", 0);
+	portfree(port);
+}
+
+// assumes b is locked
+static Centry *
+cachelookup(Bridge *b, uchar d[Eaddrlen])
+{
+	int i;
+	uint h;
+	Centry *p;
+	long sec;
+
+	// dont cache multicast or broadcast
+	if(d[0] & 1)
+		return 0;
+
+	h = 0;
+	for(i=0; i<Eaddrlen; i++) {
+		h *= 7;
+		h += d[i];
+	}
+	h %= CacheHash;
+	p = b->cache + h;
+	sec = TK2SEC(m->ticks);
+	for(i=0; i<CacheLook; i++,p++) {
+		if(memcmp(d, p->d, Eaddrlen) == 0) {
+			p->dst++;
+			if(sec >= p->expire) {
+				log(b, Logcache, "expired cache entry: %E %d\n",
+					d, p->port);
+				return nil;
+			}
+			p->expire = sec + CacheTimeout;
+			return p;
+		}
+	}
+	log(b, Logcache, "cache miss: %E\n", d);
+	return nil;
+}
+
+// assumes b is locked
+static void
+cacheupdate(Bridge *b, uchar d[Eaddrlen], int port)
+{
+	int i;
+	uint h;
+	Centry *p, *pp;
+	long sec;
+
+	// dont cache multicast or broadcast
+	if(d[0] & 1) {
+		log(b, Logcache, "bad source address: %E\n", d);
+		return;
+	}
+	
+	h = 0;
+	for(i=0; i<Eaddrlen; i++) {
+		h *= 7;
+		h += d[i];
+	}
+	h %= CacheHash;
+	p = b->cache + h;
+	pp = p;
+	sec = p->expire;
+
+	// look for oldest entry
+	for(i=0; i<CacheLook; i++,p++) {
+		if(memcmp(p->d, d, Eaddrlen) == 0) {
+			p->expire = TK2SEC(m->ticks) + CacheTimeout;
+			if(p->port != port) {
+				log(b, Logcache, "NIC changed port %d->%d: %E\n",
+					p->port, port, d);
+				p->port = port;
+			}
+			p->src++;
+			return;
+		}
+		if(p->expire < sec) {
+			sec = p->expire;
+			pp = p;
+		}
+	}
+	if(pp->expire != 0)
+		log(b, Logcache, "bumping from cache: %E %d\n", pp->d, pp->port);
+	pp->expire = TK2SEC(m->ticks) + CacheTimeout;
+	memmove(pp->d, d, Eaddrlen);
+	pp->port = port;
+	pp->src = 1;
+	pp->dst = 0;
+	log(b, Logcache, "adding to cache: %E %d\n", pp->d, pp->port);
+}
+
+// assumes b is locked
+static void
+cacheflushport(Bridge *b, int port)
+{
+	Centry *ce;
+	int i;
+
+	ce = b->cache;
+	for(i=0; i<CacheSize; i++,ce++) {
+		if(ce->port != port)
+			continue;
+		memset(ce, 0, sizeof(Centry));
+	}
+}
+
+static char *
+cachedump(Bridge *b)
+{
+	int i, n;
+	long sec, off;
+	char *buf, *p, *ep;
+	Centry *ce;
+	char c;
+
+	qlock(b);
+	if(waserror()) {
+		qunlock(b);
+		nexterror();
+	}
+	sec = TK2SEC(m->ticks);
+	n = 0;
+	for(i=0; i<CacheSize; i++)
+		if(b->cache[i].expire != 0)
+			n++;
+	
+	n *= 51;	// change if print format is changed
+	n += 10;	// some slop at the end
+	buf = malloc(n);
+	p = buf;
+	ep = buf + n;
+	ce = b->cache;
+	off = seconds() - sec;
+	for(i=0; i<CacheSize; i++,ce++) {
+		if(ce->expire == 0)
+			continue;	
+		c = (sec < ce->expire)?'v':'e';
+		p += snprint(p, ep-p, "%E %2d %10ld %10ld %10ld %c\n", ce->d,
+			ce->port, ce->src, ce->dst, ce->expire+off, c);
+	}
+	*p = 0;
+	poperror();
+	qunlock(b);
+
+	return buf;
+}
+
+
+
+// assumes b is locked
+static void
+ethermultiwrite(Bridge *b, Block *bp, Port *port)
+{
+	Chan *c;
+	Block *bp2;
+	Etherpkt *ep;
+	int i, mcast, bcast;
+	static uchar bcastaddr[Eaddrlen] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
+
+	if(waserror()) {
+		if(bp)
+			freeb(bp);
+		nexterror();
+	}
+	
+	ep = (Etherpkt*)bp->rp;
+	mcast = ep->d[0] & 1;
+	if(mcast)
+		bcast = memcmp(ep->d, bcastaddr, Eaddrlen) == 0;
+	else
+		bcast = 0;
+
+	c = nil;
+	for(i=0; i<b->nport; i++) {
+		if(i == port->id || b->port[i] == nil)
+			continue;
+		if(mcast && !bcast && !b->port[i]->mcast)
+			continue;
+		b->port[i]->out++;
+		if(mcast)
+			b->port[i]->outmulti++;
+		else
+			b->port[i]->outunknown++;
+
+		// delay one so that the last write does not copy
+		if(c != nil) {
+			// can not use write since it changes scr addr
+			bp2 = copyblock(bp, blocklen(bp));
+			devtab[c->type]->bwrite(c, bp2, 0);
+		}
+		c = b->port[i]->data[1];
+	}
+
+	// last write free block
+	if(c) {
+		bp2 = bp; bp = nil; USED(bp);
+		devtab[c->type]->bwrite(c, bp2, 0);
+	} else
+		freeb(bp);
+
+	poperror();
+}
+
+/*
+ *  process to read from the ethernet
+ */
+static void
+etherread(void *a)
+{
+	Port *port = a, *oport;
+	Bridge *b = port->bridge;
+	Block *bp, *bp2;
+	Etherpkt *ep;
+	Centry *ce;
+
+	
+	qlock(b);
+	port->readp = up;	/* hide identity under a rock for unbind */
+
+	while(!port->closed){
+		// release lock to read - error means it is time to quit
+		qunlock(b);
+		if(waserror()) {
+			qlock(b);
+			break;
+		}
+//print("devbridge: etherread: reading\n");
+		bp = devtab[port->data[0]->type]->bread(port->data[0], ETHERMAXTU, 0);
+//print("devbridge: etherread: blocklen = %d\n", blocklen(bp));
+		poperror();
+		qlock(b);
+
+		if(port->closed)
+			break;
+		if(waserror()) {
+			if(bp)
+				freeb(bp);
+print("devbridge: etherread: %r\n");
+			continue;
+		}
+		if(blocklen(bp) < ETHERMINTU)
+			error("short packet");
+		port->in++;
+		ep = (Etherpkt*)bp->rp;
+		cacheupdate(b, ep->s, port->id);
+
+		if(ep->d[0] & 1) {
+			log(b, Logmcast, "mulitcast: port=%d src=%E dst=%E type=%#.4ux\n",
+				port->id, ep->s, ep->d, (ep->type[0]<<8)|ep->type[1] );
+			port->inmulti++;
+			bp2 = bp; bp = nil;
+			ethermultiwrite(b, bp2, port);
+		} else {
+			ce = cachelookup(b, ep->d);
+			if(ce == nil) {
+				b->miss++;
+				port->inunknown++;
+				bp2 = bp; bp = nil;
+				ethermultiwrite(b, bp2, port);
+			} else if (ce->port != port->id) {
+				b->hit++;
+				bp2 = bp; bp = nil;
+				oport = b->port[ce->port];
+				oport->out++;
+				devtab[oport->data[1]->type]->bwrite(oport->data[1], bp2, 0);
+			}
+		}
+
+		poperror();
+		if(bp)
+			freeb(bp);
+	}
+print("etherread: trying to exit\n");
+	port->readp = nil;
+	portfree(port);
+	qunlock(b);
+	pexit("hangup", 1);
+}
+
+// hold b lock
+static void
+portfree(Port *port)
+{
+	port->ref--;
+	if(port->ref < 0)
+		panic("portfree: bad ref");
+	if(port->ref > 0)
+		return;
+
+	if(port->data[0])
+		cclose(port->data[0]);
+	if(port->data[1])
+		cclose(port->data[1]);
+	memset(port, 0, sizeof(Port));
+	free(port);
+}
+
+Dev bridgedevtab = {
+	'B',
+	"bridge",
+
+	devreset,
+	bridgeinit,
+	bridgeattach,
+	devclone,
+	bridgewalk,
+	bridgestat,
+	bridgeopen,
+	devcreate,
+	bridgeclose,
+	bridgeread,
+	devbread,
+	bridgewrite,
+	devbwrite,
+	devremove,
+	devwstat,
+};
diff --git a/port/devroot.c b/port/devroot.c
index f6f04c1d7a21eae487c03ec901e65a3679c75f30..d533eae91324a973c07ec4794247e860f2388d11 100644
--- a/port/devroot.c
+++ b/port/devroot.c
@@ -14,6 +14,9 @@ enum{
 	Qnet,
 	Qnetalt,
 	Qrecover,
+	Qroot,		/* boot root */
+
+	// add new entries above this
 	Qboot,		/* readable files */
 
 	Nfiles=13,	/* max root files */
@@ -30,6 +33,7 @@ Dirtab rootdir[Nfiles]={
 	"net",		{Qnet|CHDIR},	0,	0777,
 	"net.alt",	{Qnetalt|CHDIR},	0,	0777,
 	"recover",	{Qrecover},	0,	0777,
+	"root",		{Qroot|CHDIR},	0,	0777,
 };
 
 static uchar	*rootdata[Nfiles];
diff --git a/port/log.c b/port/log.c
new file mode 100644
index 0000000000000000000000000000000000000000..0d68028b4779994b54624fb35653f4f2ffe1f6e5
--- /dev/null
+++ b/port/log.c
@@ -0,0 +1,175 @@
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "../port/error.h"
+
+static char Ebadlogctl[] = "unknown log ctl message";
+
+enum {
+	Nlog		= 4*1024,
+};
+
+void
+logopen(Log *alog)
+{
+	lock(alog);
+	if(waserror()){
+		unlock(alog);
+		nexterror();
+	}
+	if(alog->opens == 0){
+		if(alog->buf == nil)
+			alog->buf = malloc(Nlog);
+		alog->rptr = alog->buf;
+		alog->end = alog->buf + Nlog;
+	}
+	alog->opens++;
+	unlock(alog);
+	poperror();
+}
+
+void
+logclose(Log *alog)
+{
+	lock(alog);
+	if(waserror()){
+		unlock(alog);
+		nexterror();
+	}
+	alog->opens--;
+	if(alog->opens == 0){
+		free(alog->buf);
+		alog->buf = nil;
+	}
+	unlock(alog);
+	poperror();
+}
+
+static int
+logready(void *a)
+{
+	Log *alog = a;
+
+	return alog->len;
+}
+
+long
+logread(Log *alog, void *a, ulong, long n)
+{
+	int i, d;
+	char *p, *rptr;
+
+	qlock(&alog->readq);
+	if(waserror()){
+		qunlock(&alog->readq);
+		nexterror();
+	}
+
+	for(;;){
+		lock(alog);
+		if(alog->len){
+			if(n > alog->len)
+				n = alog->len;
+			d = 0;
+			rptr = alog->rptr;
+			alog->rptr += n;
+			if(alog->rptr >= alog->end){
+				d = alog->rptr - alog->end;
+				alog->rptr = alog->buf + d;
+			}
+			alog->len -= n;
+			unlock(alog);
+
+			i = n;
+			p = a;
+			if(d){
+				memmove(p, rptr, d);
+				i -= d;
+				p += d;
+				rptr = alog->buf;
+			}
+			memmove(p, rptr, i);
+			break;
+		}
+		else
+			unlock(alog);
+
+		sleep(&alog->readr, logready, alog);
+	}
+
+	qunlock(&alog->readq);
+	poperror();
+
+	return n;
+}
+
+char*
+logctl(Log *alog, int argc, char *argv[], Logflag *flags)
+{
+	int i, n, set;
+	Logflag *fp;
+
+	if(argc < 2)
+		return Ebadlogctl;
+
+	if(strcmp("set", argv[0]) == 0)
+		set = 1;
+	else if(strcmp("clear", argv[0]) == 0)
+		set = 0;
+	else
+		return Ebadlogctl;
+
+	for(i = 1; i < argc; i++){
+		for(fp = flags; fp->name; fp++)
+			if(strcmp(fp->name, argv[i]) == 0)
+				break;
+		if(fp->name == nil)
+			continue;
+		if(set)
+			alog->logmask |= fp->mask;
+		else
+			alog->logmask &= ~fp->mask;
+	}
+
+	return nil;
+}
+
+void
+log(Log *alog, int mask, char *fmt, ...)
+{
+	char buf[128], *t, *fp;
+	int i, n;
+	va_list arg;
+
+	if(!(alog->logmask & mask))
+		return;
+
+	va_start(arg, fmt);
+	n = doprint(buf, buf+sizeof(buf), fmt, arg) - buf;
+	va_end(arg);
+
+	if(alog->opens == 0)
+		return;
+
+	lock(alog);
+	i = alog->len + n - Nlog;
+	if(i > 0){
+		alog->len -= i;
+		alog->rptr += i;
+		if(alog->rptr >= alog->end)
+			alog->rptr = alog->buf + (alog->rptr - alog->end);
+	}
+	t = alog->rptr + alog->len;
+	fp = buf;
+	alog->len += n;
+	while(n-- > 0){
+		if(t >= alog->end)
+			t = alog->buf + (t - alog->end);
+		*t++ = *fp++;
+	}
+	unlock(alog);
+
+	wakeup(&alog->readr);
+}
diff --git a/port/netif.c b/port/netif.c
index a9425e8d9f078c3920a1e5179f5aecfc9a0baff6..14bbb76cbfe02dab5c8c76540e5a5b742ee080f6 100644
--- a/port/netif.c
+++ b/port/netif.c
@@ -59,17 +59,26 @@ netifgen(Chan *c, void *vp, int, int i, Dir *dp)
 	/* second level contains clone plus all the conversations */
 	t = NETTYPE(c->qid.path);
 	if(t == N2ndqid || t == Ncloneqid){
-		if(i == 0){
+		switch(i) {
+		case 0:
 			q.path = Ncloneqid;
 			devdir(c, q, "clone", 0, eve, 0666, dp);
-		}else if(i <= nif->nfile){
-			if(nif->f[i-1] == 0)
+			break;
+		case 1:
+			q.path = Naddrqid;
+			devdir(c, q, "addr", 0, eve, 0666, dp);
+			break;
+		default:
+			i -= 2;
+			if(i >= nif->nfile)
+				return -1;
+			if(nif->f[i] == 0)
 				return 0;
-			q.path = CHDIR|NETQID(i-1, N3rdqid);
-			sprint(buf, "%d", i-1);
+			q.path = CHDIR|NETQID(i, N3rdqid);
+			sprint(buf, "%d", i);
 			devdir(c, q, buf, 0, eve, 0555, dp);
-		}else
-			return -1;
+			break;
+		}
 		return 1;
 	}
 
@@ -192,6 +201,14 @@ netifread(Netif *nif, Chan *c, void *a, long n, ulong offset)
 		n = readstr(offset, a, n, p);
 		free(p);
 		return n;
+	case Naddrqid:
+		p = malloc(READSTR);
+		j = 0;
+		for(i = 0; i < nif->alen; i++)
+			j += snprint(p+j, READSTR-j, "%2.2ux", nif->addr[i]);
+		n = readstr(offset, a, n, p);
+		free(p);
+		return n;
 	case Ntypeqid:
 		f = nif->f[NETID(c->qid.path)];
 		return readnum(offset, a, n, f->type, NUMSIZE);
diff --git a/port/netif.h b/port/netif.h
index 567d49be594f8b700b0ba8cb17b63358970104b7..b7e21733d848dc2b30fa671390e1a66e611c8fef 100644
--- a/port/netif.h
+++ b/port/netif.h
@@ -9,6 +9,7 @@ enum
 	Nmhash=		31,
 
 	Ncloneqid=	1,
+	Naddrqid,
 	N2ndqid,
 	N3rdqid,
 	Ndataqid,
diff --git a/port/parse.c b/port/parse.c
new file mode 100644
index 0000000000000000000000000000000000000000..b35c1151f547e1617e8a41e25c6041c11d9eddba
--- /dev/null
+++ b/port/parse.c
@@ -0,0 +1,44 @@
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"../port/error.h"
+
+int
+parsefields(char *lp, char **fields, int n, char *sep)
+{
+	int i;
+
+	for(i=0; lp && *lp && i<n; i++){
+		while(*lp && strchr(sep, *lp) != 0)
+			*lp++=0;
+		if(*lp == 0)
+			break;
+		fields[i]=lp;
+		while(*lp && strchr(sep, *lp) == 0)
+			lp++;
+	}
+	return i;
+}
+
+/*
+ *  parse a command written to a device
+ */
+Cmdbuf*
+parsecmd(char *p, int n)
+{
+	Cmdbuf *cb;
+
+	cb = smalloc(sizeof(*cb));
+	
+	if(n > sizeof(cb->buf)-1)
+		n = sizeof(cb->buf)-1;
+	memmove(cb->buf, p, n);
+	if(n > 0 && cb->buf[n-1] == '\n')
+		n--;
+	cb->buf[n] = '\0';
+	cb->nf = parsefields(cb->buf, cb->f, nelem(cb->f), " ");
+	return cb;
+}
+
diff --git a/port/portdat.h b/port/portdat.h
index 55736d7cad04aec4119add597ad8cd3de0a11d2f..2509e712e4d086a6e0f4f61c35fb81cc7ff5816e 100644
--- a/port/portdat.h
+++ b/port/portdat.h
@@ -1,6 +1,7 @@
 typedef struct Alarms	Alarms;
 typedef struct Block	Block;
 typedef struct Chan	Chan;
+typedef struct Cmdbuf	Cmdbuf;
 typedef struct Crypt	Crypt;
 typedef struct Dev	Dev;
 typedef struct Dirtab	Dirtab;
@@ -9,6 +10,8 @@ typedef struct Evalue	Evalue;
 typedef struct Fgrp	Fgrp;
 typedef struct Image	Image;
 typedef struct List	List;
+typedef struct Log	Log;
+typedef struct Logflag	Logflag;
 typedef struct Mntcache Mntcache;
 typedef struct Mount	Mount;
 typedef struct Mntrpc	Mntrpc;
@@ -39,6 +42,7 @@ typedef struct Target	Target;
 typedef struct Waitq	Waitq;
 typedef int    Devgen(Chan*, Dirtab*, int, int, Dir*);
 
+
 #include <auth.h>
 #include <fcall.h>
 
@@ -716,6 +720,35 @@ enum
 	LRESPROF	= 3,
 };
 
+/*
+ *  action log
+ */
+struct Log {
+	Lock;
+	int	opens;
+	char*	buf;
+	char	*end;
+	char	*rptr;
+	int	len;
+
+	int	logmask;	/* mask of things to debug */
+
+	QLock	readq;
+	Rendez	readr;
+};
+
+struct Logflag {
+	char*	name;
+	int	mask;
+};
+
+struct Cmdbuf
+{
+	char	buf[64];
+	char	*f[16];
+	int	nf;
+};
+
 extern int nsyscall;
 
 #pragma	varargck	argpos	print	1
diff --git a/port/portfns.h b/port/portfns.h
index 1fb78a2f5382e605eb01bd7a6277055c9359ba19..fcf0791ca6677c338a4c2be0d34a50ff49e4720c 100644
--- a/port/portfns.h
+++ b/port/portfns.h
@@ -142,6 +142,11 @@ void		ksetenv(char*, char*);
 long		latin1(uchar*, int);
 void		lock(Lock*);
 void		lockinit(void);
+void		logopen(Log*);
+void		logclose(Log*);
+char*		logctl(Log*, int, char**, Logflag*);
+long		logread(Log*, void*, ulong, long);
+void		log(Log*, int, char*, ...);
 Page*		lookpage(Image*, ulong);
 void		machinit(void);
 void*		mallocz(ulong, int);
@@ -179,6 +184,7 @@ void		pagersummary(void);
 void		panic(char*, ...);
 int		parseether(uchar*, char*);
 int		parsefields(char*, char**, int, char*);
+Cmdbuf*		parsecmd(char *a, int n);
 void		pexit(char*, int);
 void		pgrpcpy(Pgrp*, Pgrp*);
 void		pgrpnote(ulong, char*, long, int);