oexportfs: move legacy code for cpu and import to separate program

The initial protocol handling in exportfs for
cpu and import services is a huge mess.

Saparate the code out into its own program with
its own oexportfs(4) manpage.

1 files changed, 14 insertions, 836 deletions

diff --git a/sys/src/cmd/exportfs/exportfs.c b/sys/src/cmd/exportfs/exportfs.c
index 275151a6c..b17cec499 100644
--- a/sys/src/cmd/exportfs/exportfs.c
+++ b/sys/src/cmd/exportfs/exportfs.c
@@ -1,135 +1,44 @@
-/*
- * exportfs - Export a plan 9 name space across a network
- */
 #include <u.h>
 #include <libc.h>
-#include <auth.h>
 #include <fcall.h>
-#include <libsec.h>
 #define Extern
 #include "exportfs.h"
 
-#define QIDPATH	((1LL<<48)-1)
-vlong newqid = 0;
-
-enum {
-	Encnone,
-	Encssl,
-	Enctls,
-};
-
-void (*fcalls[])(Fsrpc*) =
-{
-	[Tversion]	Xversion,
-	[Tauth]	Xauth,
-	[Tflush]	Xflush,
-	[Tattach]	Xattach,
-	[Twalk]		Xwalk,
-	[Topen]		slave,
-	[Tcreate]	Xcreate,
-	[Tclunk]	Xclunk,
-	[Tread]		slave,
-	[Twrite]	slave,
-	[Tremove]	Xremove,
-	[Tstat]		Xstat,
-	[Twstat]	Xwstat,
-};
-
-/* accounting and debugging counters */
-int	filecnt;
-int	freecnt;
-int	qidcnt;
-int	qfreecnt;
-int	ncollision;
-
 int	srvfd = -1;
-int	nonone = 1;
-char	*filterp;
-char	*ealgs = "rc4_256 sha1";
-char	*aanfilter = "/bin/aan";
-int	encproto = Encnone;
 int	readonly;
 
-static void mksecret(char *, uchar *);
-static char *anstring  = "tcp!*!0";
-
-char *netdir = "", *local = "", *remote = "";
-
-void	filter(int, char *, char *);
-
 void
 usage(void)
 {
-	fprint(2, "usage: %s [-adnsR] [-f dbgfile] [-m msize] [-r root] "
-		"[-S srvfile] [-e 'crypt hash'] [-P exclusion-file] "
-		"[-A announce-string] [-B address]\n", argv0);
+	fprint(2, "usage: %s [-dsR] [-f dbgfile] [-m msize] [-r root] "
+		"[-S srvfile] [-P exclusion-file]\n", argv0);
 	fatal("usage");
 }
 
-static void
-noteconn(int fd)
-{
-	NetConnInfo *nci;
-
-	nci = getnetconninfo(nil, fd);
-	if(nci == nil)
-		return;
-	netdir = estrdup(nci->dir);
-	local = estrdup(nci->lsys);
-	remote = estrdup(nci->rsys);
-	freenetconninfo(nci);
-}
-
 void
 main(int argc, char **argv)
 {
-	char buf[ERRMAX], ebuf[ERRMAX], initial[4], *ini, *srvfdfile;
-	char *dbfile, *srv, *na, *nsfile, *keyspec;
-	int doauth, n, fd;
-	AuthInfo *ai;
-	Fsrpc *r;
+	char *dbfile, *srv, *srvfdfile;
+	int n;
 
 	dbfile = "/tmp/exportdb";
 	srv = nil;
 	srvfd = -1;
 	srvfdfile = nil;
-	na = nil;
-	nsfile = nil;
-	keyspec = "";
-	doauth = 0;
 
-	ai = nil;
 	ARGBEGIN{
-	case 'a':
-		doauth = 1;
-		break;
-
 	case 'd':
 		dbg++;
 		break;
 
-	case 'e':
-		ealgs = EARGF(usage());
-		if(*ealgs == 0 || strcmp(ealgs, "clear") == 0)
-			ealgs = nil;
-		break;
-
 	case 'f':
 		dbfile = EARGF(usage());
 		break;
 
-	case 'k':
-		keyspec = EARGF(usage());
-		break;
-
 	case 'm':
 		messagesize = strtoul(EARGF(usage()), nil, 0);
 		break;
 
-	case 'n':
-		nonone = 0;
-		break;
-
 	case 'r':
 		srv = EARGF(usage());
 		break;
@@ -138,22 +47,10 @@ main(int argc, char **argv)
 		srv = "/";
 		break;
 
-	case 'A':
-		anstring = EARGF(usage());
-		break;
-
-	case 'B':
-		na = EARGF(usage());
-		break;
-
 	case 'F':
 		/* accepted but ignored, for backwards compatibility */
 		break;
 
-	case 'N':
-		nsfile = EARGF(usage());
-		break;
-
 	case 'P':
 		patternfile = EARGF(usage());
 		break;
@@ -173,52 +70,15 @@ main(int argc, char **argv)
 	}ARGEND
 	USED(argc, argv);
 
-	if(na == nil && doauth){
-		/*
-		 * We use p9any so we don't have to visit this code again, with the
-		 * cost that this code is incompatible with the old world, which
-		 * requires p9sk2. (The two differ in who talks first, so compatibility
-		 * is awkward.)
-		 */
-		ai = auth_proxy(0, auth_getkey, "proto=p9any role=server %s", keyspec);
-		if(ai == nil)
-			fatal("auth_proxy: %r");
-		if(nonone && strcmp(ai->cuid, "none") == 0)
-			fatal("exportfs by none disallowed");
-		if(auth_chuid(ai, nsfile) < 0)
-			fatal("auth_chuid: %r");
-		else {	/* chown network connection */
-			Dir nd;
-			nulldir(&nd);
-			nd.mode = 0660;
-			nd.uid = ai->cuid;
-			dirfwstat(0, &nd);
-		}
-		putenv("service", "exportfs");
-	}
-
 	if(srvfdfile != nil){
+		if(srv != nil){
+			fprint(2, "exportfs: -S cannot be used with -r or -s\n");
+			usage();
+		}
 		if((srvfd = open(srvfdfile, ORDWR)) < 0)
 			fatal("open %s: %r", srvfdfile);
-	}
-
-	if(na != nil){
-		if(srv == nil)
-			fatal("-B requires -s");
-
-		local = "me";
-		remote = na;
-		if((fd = dial(netmkaddr(na, 0, "importfs"), 0, 0, 0)) < 0)
-			fatal("can't dial %s: %r", na);
-	
-		ai = auth_proxy(fd, auth_getkey, "proto=p9any role=client %s", keyspec);
-		if(ai == nil)
-			fatal("%r: %s", na);
-
-		dup(fd, 0);
-		dup(fd, 1);
-		close(fd);
-	}
+	} else if(srv == nil)
+		usage();
 
 	exclusions();
 
@@ -228,11 +88,6 @@ main(int argc, char **argv)
 		close(n);
 	}
 
-	if(srvfd >= 0 && srv != nil){
-		fprint(2, "exportfs: -S cannot be used with -r or -s\n");
-		usage();
-	}
-
 	DEBUG(DFD, "exportfs: started\n");
 
 	rfork(RFNOTEG|RFREND);
@@ -246,695 +101,18 @@ main(int argc, char **argv)
 
 	fmtinstall('F', fcallfmt);
 
-	/*
-	 * Get tree to serve from network connection,
-	 * check we can get there and ack the connection
- 	 */
-	if(srvfd != -1) {
-		/* do nothing */
-	}
-	else if(srv != nil) {
+	if(srvfd == -1) {
 		if(chdir(srv) < 0) {
+			char ebuf[ERRMAX];
 			ebuf[0] = '\0';
 			errstr(ebuf, sizeof ebuf);
-			r = getsbuf();
-			r->work.tag = NOTAG;
-			r->work.fid = NOFID;
-			r->work.type = Rerror;
-			r->work.ename = ebuf;
-			n = convS2M(&r->work, r->buf, messagesize);
-			write(0, r->buf, n);
 			DEBUG(DFD, "chdir(\"%s\"): %s\n", srv, ebuf);
-			exits(ebuf);
+			mounterror(ebuf);
 		}
 		DEBUG(DFD, "invoked as server for %s", srv);
-		strncpy(buf, srv, sizeof buf);
-	}
-	else {
-		noteconn(0);
-		buf[0] = 0;
-		n = read(0, buf, sizeof(buf)-1);
-		if(n < 0) {
-			errstr(buf, sizeof buf);
-			fprint(0, "read(0): %s\n", buf);
-			DEBUG(DFD, "read(0): %s\n", buf);
-			exits(buf);
-		}
-		buf[n] = 0;
-		if(chdir(buf) < 0) {
-			errstr(ebuf, sizeof ebuf);
-			fprint(0, "chdir(%d:\"%s\"): %s\n", n, buf, ebuf);
-			DEBUG(DFD, "chdir(%d:\"%s\"): %s\n", n, buf, ebuf);
-			exits(ebuf);
-		}
 	}
 
 	DEBUG(DFD, "\niniting root\n");
 	initroot();
-
-	DEBUG(DFD, "exportfs: %s\n", buf);
-
-	if(srv == nil && srvfd == -1 && write(0, "OK", 2) != 2)
-		fatal("open ack write");
-
-	ini = initial;
-	n = readn(0, initial, sizeof(initial));
-	if(n == 0)
-		fatal(nil);	/* port scan or spurious open/close on exported /srv file (unmount) */
-	if(n < sizeof(initial))
-		fatal("can't read initial string: %r");
-
-	if(memcmp(ini, "impo", 4) == 0) {
-		char buf[128], *p, *args[3];
-
-		ini = nil;
-		p = buf;
-		for(;;){
-			if((n = read(0, p, 1)) < 0)
-				fatal("can't read impo arguments: %r");
-			if(n == 0)
-				fatal("connection closed while reading arguments");
-			if(*p == '\n') 
-				*p = '\0';
-			if(*p++ == '\0')
-				break;
-			if(p >= buf + sizeof(buf))
-				fatal("import parameters too long");
-		}
-		
-		if(tokenize(buf, args, nelem(args)) != 2)
-			fatal("impo arguments invalid: impo%s...", buf);
-
-		if(strcmp(args[0], "aan") == 0)
-			filterp = aanfilter;
-		else if(strcmp(args[0], "nofilter") != 0)
-			fatal("import filter argument unsupported: %s", args[0]);
-
-		if(strcmp(args[1], "ssl") == 0)
-			encproto = Encssl;
-		else if(strcmp(args[1], "tls") == 0)
-			encproto = Enctls;
-		else if(strcmp(args[1], "clear") != 0)
-			fatal("import encryption proto unsupported: %s", args[1]);
-
-		if(encproto == Enctls)
-			fatal("%s: tls has not yet been implemented", argv[0]);
-	}
-
-	if(encproto != Encnone && ealgs != nil && ai != nil) {
-		uchar key[16], digest[SHA1dlen];
-		char fromclientsecret[21];
-		char fromserversecret[21];
-		int i;
-
-		if(ai->nsecret < 8)
-			fatal("secret too small for ssl");
-		memmove(key+4, ai->secret, 8);
-
-		/* exchange random numbers */
-		srand(truerand());
-		for(i = 0; i < 4; i++)
-			key[i+12] = rand();
-
-		if(ini != nil) 
-			fatal("Protocol botch: old import");
-		if(readn(0, key, 4) != 4)
-			fatal("can't read key part; %r");
-
-		if(write(0, key+12, 4) != 4)
-			fatal("can't write key part; %r");
-
-		/* scramble into two secrets */
-		sha1(key, sizeof(key), digest, nil);
-		mksecret(fromclientsecret, digest);
-		mksecret(fromserversecret, digest+10);
-
-		if(filterp != nil)
-			filter(0, filterp, na);
-
-		switch(encproto) {
-		case Encssl:
-			fd = pushssl(0, ealgs, fromserversecret, fromclientsecret, nil);
-			if(fd < 0)
-				fatal("can't establish ssl connection: %r");
-			if(fd != 0){
-				dup(fd, 0);
-				close(fd);
-			}
-			break;
-		case Enctls:
-		default:
-			fatal("Unsupported encryption protocol");
-		}
-	}
-	else if(filterp != nil) {
-		if(ini != nil)
-			fatal("Protocol botch: don't know how to deal with this");
-		filter(0, filterp, na);
-	}
-	dup(0, 1);
-
-	if(ai != nil)
-		auth_freeAI(ai);
-
-	if(ini != nil){
-		r = getsbuf();
-		memmove(r->buf, ini, BIT32SZ);
-		n = GBIT32(r->buf);
-		if(n <= BIT32SZ || n > messagesize)
-			fatal("bad length in 9P2000 message header");
-		n -= BIT32SZ;
-		if(readn(0, r->buf+BIT32SZ, n) != n)
-			fatal(nil);
-		n += BIT32SZ;
-		goto Message;
-	}
-
-	/*
-	 * Start serving file requests from the network
-	 */
-	for(;;) {
-		r = getsbuf();
-		n = read9pmsg(0, r->buf, messagesize);
-		if(n <= 0)
-			fatal(nil);
-	Message:
-		if(convM2S(r->buf, n, &r->work) != n)
-			fatal("convM2S format error");
-
-		DEBUG(DFD, "%F\n", &r->work);
-		(fcalls[r->work.type])(r);
-	}
-}
-
-void
-reply(Fcall *r, Fcall *t, char *err)
-{
-	uchar *data;
-	int n;
-
-	t->tag = r->tag;
-	t->fid = r->fid;
-	if(err != nil) {
-		t->type = Rerror;
-		t->ename = err;
-	}
-	else 
-		t->type = r->type + 1;
-
-	DEBUG(DFD, "\t%F\n", t);
-
-	data = malloc(messagesize);	/* not mallocz; no need to clear */
-	if(data == nil)
-		fatal(Enomem);
-	n = convS2M(t, data, messagesize);
-	if(write(0, data, n) != n){
-		/* not fatal, might have got a note due to flush */
-		fprint(2, "exportfs: short write in reply: %r\n");
-	}
-	free(data);
-}
-
-Fid *
-getfid(int nr)
-{
-	Fid *f;
-
-	for(f = fidhash(nr); f != nil; f = f->next)
-		if(f->nr == nr)
-			return f;
-
-	return nil;
-}
-
-int
-freefid(int nr)
-{
-	Fid *f, **l;
-	char buf[128];
-
-	l = &fidhash(nr);
-	for(f = *l; f != nil; f = f->next) {
-		if(f->nr == nr) {
-			if(f->mid) {
-				snprint(buf, sizeof(buf), "/mnt/exportfs/%d", f->mid);
-				unmount(0, buf);
-				psmap[f->mid] = 0;
-			}
-			if(f->f != nil) {
-				freefile(f->f);
-				f->f = nil;
-			}
-			if(f->dir != nil){
-				free(f->dir);
-				f->dir = nil;
-			}
-			*l = f->next;
-			f->next = fidfree;
-			fidfree = f;
-			return 1;
-		}
-		l = &f->next;
-	}
-
-	return 0;	
-}
-
-Fid *
-newfid(int nr)
-{
-	Fid *new, **l;
-	int i;
-
-	l = &fidhash(nr);
-	for(new = *l; new != nil; new = new->next)
-		if(new->nr == nr)
-			return nil;
-
-	if(fidfree == nil) {
-		fidfree = emallocz(sizeof(Fid) * Fidchunk);
-
-		for(i = 0; i < Fidchunk-1; i++)
-			fidfree[i].next = &fidfree[i+1];
-
-		fidfree[Fidchunk-1].next = nil;
-	}
-
-	new = fidfree;
-	fidfree = new->next;
-
-	memset(new, 0, sizeof(Fid));
-	new->next = *l;
-	*l = new;
-	new->nr = nr;
-	new->fid = -1;
-	new->mid = 0;
-
-	return new;	
-}
-
-static struct {
-	Lock;
-	Fsrpc	*free;
-
-	/* statistics */
-	int	nalloc;
-	int	nfree;
-}	sbufalloc;
-
-Fsrpc *
-getsbuf(void)
-{
-	Fsrpc *w;
-
-	lock(&sbufalloc);
-	w = sbufalloc.free;
-	if(w != nil){
-		sbufalloc.free = w->next;
-		w->next = nil;
-		sbufalloc.nfree--;
-		unlock(&sbufalloc);
-	} else {
-		sbufalloc.nalloc++;
-		unlock(&sbufalloc);
-		w = emallocz(sizeof(*w) + messagesize);
-	}
-	w->flushtag = NOTAG;
-	return w;
-}
-
-void
-putsbuf(Fsrpc *w)
-{
-	w->flushtag = NOTAG;
-	lock(&sbufalloc);
-	w->next = sbufalloc.free;
-	sbufalloc.free = w;
-	sbufalloc.nfree++;
-	unlock(&sbufalloc);
-}
-
-void
-freefile(File *f)
-{
-	File *parent, *child;
-
-	while(--f->ref == 0){
-		freecnt++;
-		DEBUG(DFD, "free %s\n", f->name);
-		/* delete from parent */
-		parent = f->parent;
-		if(parent->child == f)
-			parent->child = f->childlist;
-		else{
-			for(child = parent->child; child->childlist != f; child = child->childlist) {
-				if(child->childlist == nil)
-					fatal("bad child list");
-			}
-			child->childlist = f->childlist;
-		}
-		freeqid(f->qidt);
-		free(f->name);
-		free(f);
-		f = parent;
-	}
-}
-
-File *
-file(File *parent, char *name)
-{
-	Dir *dir;
-	char *path;
-	File *f;
-
-	DEBUG(DFD, "\tfile: 0x%p %s name %s\n", parent, parent->name, name);
-
-	path = makepath(parent, name);
-	if(patternfile != nil && excludefile(path)){
-		free(path);
-		return nil;
-	}
-	dir = dirstat(path);
-	free(path);
-	if(dir == nil)
-		return nil;
-
-	for(f = parent->child; f != nil; f = f->childlist)
-		if(strcmp(name, f->name) == 0)
-			break;
-
-	if(f == nil){
-		f = emallocz(sizeof(File));
-		f->name = estrdup(name);
-
-		f->parent = parent;
-		f->childlist = parent->child;
-		parent->child = f;
-		parent->ref++;
-		f->ref = 0;
-		filecnt++;
-	}
-	f->ref++;
-	f->qid.type = dir->qid.type;
-	f->qid.vers = dir->qid.vers;
-	f->qidt = uniqueqid(dir);
-	f->qid.path = f->qidt->uniqpath;
-
-	f->inval = 0;
-
-	free(dir);
-
-	return f;
-}
-
-void
-initroot(void)
-{
-	Dir *dir;
-
-	root = emallocz(sizeof(File));
-	root->name = estrdup(".");
-
-	dir = dirstat(root->name);
-	if(dir == nil)
-		fatal("root stat");
-
-	root->ref = 1;
-	root->qid.vers = dir->qid.vers;
-	root->qidt = uniqueqid(dir);
-	root->qid.path = root->qidt->uniqpath;
-	root->qid.type = QTDIR;
-	free(dir);
-
-	psmpt = emallocz(sizeof(File));
-	psmpt->name = estrdup("/");
-
-	dir = dirstat(psmpt->name);
-	if(dir == nil)
-		return;
-
-	psmpt->ref = 1;
-	psmpt->qid.vers = dir->qid.vers;
-	psmpt->qidt = uniqueqid(dir);
-	psmpt->qid.path = psmpt->qidt->uniqpath;
-	free(dir);
-
-	psmpt = file(psmpt, "mnt");
-	if(psmpt == nil)
-		return;
-	psmpt = file(psmpt, "exportfs");
-}
-
-char*
-makepath(File *p, char *name)
-{
-	int i, n;
-	char *c, *s, *path, *seg[256];
-
-	seg[0] = name;
-	n = strlen(name)+2;
-	for(i = 1; i < 256 && p; i++, p = p->parent){
-		seg[i] = p->name;
-		n += strlen(p->name)+1;
-	}
-	path = emallocz(n);
-	s = path;
-
-	while(i--) {
-		for(c = seg[i]; *c; c++)
-			*s++ = *c;
-		*s++ = '/';
-	}
-	while(s[-1] == '/')
-		s--;
-	*s = '\0';
-
-	return path;
-}
-
-int
-qidhash(vlong path)
-{
-	int h, n;
-
-	h = 0;
-	for(n=0; n<64; n+=Nqidbits){
-		h ^= path;
-		path >>= Nqidbits;
-	}
-	return h & (Nqidtab-1);
-}
-
-void
-freeqid(Qidtab *q)
-{
-	ulong h;
-	Qidtab *l;
-
-	if(--q->ref)
-		return;
-	qfreecnt++;
-	h = qidhash(q->path);
-	if(qidtab[h] == q)
-		qidtab[h] = q->next;
-	else{
-		for(l=qidtab[h]; l->next!=q; l=l->next)
-			if(l->next == nil)
-				fatal("bad qid list");
-		l->next = q->next;
-	}
-	free(q);
-}
-
-Qidtab*
-qidlookup(Dir *d)
-{
-	ulong h;
-	Qidtab *q;
-
-	h = qidhash(d->qid.path);
-	for(q=qidtab[h]; q!=nil; q=q->next)
-		if(q->type==d->type && q->dev==d->dev && q->path==d->qid.path)
-			return q;
-	return nil;
-}
-
-int
-qidexists(vlong path)
-{
-	int h;
-	Qidtab *q;
-
-	for(h=0; h<Nqidtab; h++)
-		for(q=qidtab[h]; q!=nil; q=q->next)
-			if(q->uniqpath == path)
-				return 1;
-	return 0;
-}
-
-Qidtab*
-uniqueqid(Dir *d)
-{
-	ulong h;
-	vlong path;
-	Qidtab *q;
-
-	q = qidlookup(d);
-	if(q != nil){
-		q->ref++;
-		return q;
-	}
-	path = d->qid.path;
-	while(qidexists(path)){
-		DEBUG(DFD, "collision on %s\n", d->name);
-		/* collision: find a new one */
-		ncollision++;
-		path &= QIDPATH;
-		++newqid;
-		if(newqid >= (1<<16)){
-			DEBUG(DFD, "collision wraparound\n");
-			newqid = 1;
-		}
-		path |= newqid<<48;
-		DEBUG(DFD, "assign qid %.16llux\n", path);
-	}
-	qidcnt++;
-	q = emallocz(sizeof(Qidtab));
-	q->ref = 1;
-	q->type = d->type;
-	q->dev = d->dev;
-	q->path = d->qid.path;
-	q->uniqpath = path;
-	h = qidhash(d->qid.path);
-	q->next = qidtab[h];
-	qidtab[h] = q;
-	return q;
-}
-
-void
-fatal(char *s, ...)
-{
-	char buf[ERRMAX];
-	va_list arg;
-	Proc *m;
-
-	if(s != nil) {
-		va_start(arg, s);
-		vsnprint(buf, ERRMAX, s, arg);
-		va_end(arg);
-	}
-
-	/* Clear away the slave children */
-	for(m = Proclist; m != nil; m = m->next)
-		postnote(PNPROC, m->pid, "kill");
-
-	if(s != nil) {
-		DEBUG(DFD, "%s\n", buf);
-		sysfatal("%s", buf);	/* caution: buf could contain '%' */
-	} else
-		exits(nil);
-}
-
-void*
-emallocz(uint n)
-{
-	void *p;
-
-	p = mallocz(n, 1);
-	if(p == nil)
-		fatal(Enomem);
-	setmalloctag(p, getcallerpc(&n));
-	return p;
-}
-
-char*
-estrdup(char *s)
-{
-	char *t;
-
-	t = strdup(s);
-	if(t == nil)
-		fatal(Enomem);
-	setmalloctag(t, getcallerpc(&s));
-	return t;
-}
-
-void
-filter(int fd, char *cmd, char *host)
-{
-	char addr[128], buf[256], *s, *file, *argv[16];
-	int lfd, p[2], len, argc;
-
-	if(host == nil){
-		/* Get a free port and post it to the client. */
-		if (announce(anstring, addr) < 0)
-			fatal("filter: Cannot announce %s: %r", anstring);
-
-		snprint(buf, sizeof(buf), "%s/local", addr);
-		if ((lfd = open(buf, OREAD)) < 0)
-			fatal("filter: Cannot open %s: %r", buf);
-		if ((len = read(lfd, buf, sizeof buf - 1)) < 0)
-			fatal("filter: Cannot read %s: %r", buf);
-		close(lfd);
-		buf[len] = '\0';
-		if ((s = strchr(buf, '\n')) != nil)
-			len = s - buf;
-		if (write(fd, buf, len) != len) 
-			fatal("filter: cannot write port; %r");
-	} else {
-		/* Read address string from connection */
-		if ((len = read(fd, buf, sizeof buf - 1)) < 0)
-			sysfatal("filter: cannot write port; %r");
-		buf[len] = '\0';
-
-		if ((s = strrchr(buf, '!')) == nil)
-			sysfatal("filter: illegally formatted port %s", buf);
-		strecpy(addr, addr+sizeof(addr), netmkaddr(host, "tcp", s+1));
-		strecpy(strrchr(addr, '!'), addr+sizeof(addr), s);
-	}
-
-	DEBUG(DFD, "filter: %s\n", addr);
-
-	snprint(buf, sizeof(buf), "%s", cmd);
-	argc = tokenize(buf, argv, nelem(argv)-3);
-	if (argc == 0)
-		sysfatal("filter: empty command");
-
-	if(host != nil)
-		argv[argc++] = "-c";
-	argv[argc++] = addr;
-	argv[argc] = nil;
-
-	file = argv[0];
-	if((s = strrchr(argv[0], '/')) != nil)
-		argv[0] = s+1;
-
-	if(pipe(p) < 0)
-		sysfatal("pipe: %r");
-
-	switch(rfork(RFNOWAIT|RFPROC|RFMEM|RFFDG|RFREND)) {
-	case -1:
-		fatal("filter: rfork; %r\n");
-	case 0:
-		close(fd);
-		if (dup(p[0], 1) < 0)
-			fatal("filter: Cannot dup to 1; %r");
-		if (dup(p[0], 0) < 0)
-			fatal("filter: Cannot dup to 0; %r");
-		close(p[0]);
-		close(p[1]);
-		exec(file, argv);
-		fatal("filter: exec; %r");
-	default:
-		dup(p[1], fd);
-		close(p[0]);
-		close(p[1]);
-	}
-}
-
-static void
-mksecret(char *t, uchar *f)
-{
-	sprint(t, "%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux%2.2ux",
-		f[0], f[1], f[2], f[3], f[4], f[5], f[6], f[7], f[8], f[9]);
+	io();
 }