xref: /freebsd/sys/netsmb/smb_trantcp.c (revision eb6d21b4ca6d668cf89afd99eef7baeafa712197)
1 /*-
2  * Copyright (c) 2000-2001 Boris Popov
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *    This product includes software developed by Boris Popov.
16  * 4. Neither the name of the author nor the names of any co-contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/condvar.h>
38 #include <sys/kernel.h>
39 #include <sys/lock.h>
40 #include <sys/malloc.h>
41 #include <sys/mbuf.h>
42 #include <sys/poll.h>
43 #include <sys/proc.h>
44 #include <sys/protosw.h>
45 #include <sys/signalvar.h>
46 #include <sys/socket.h>
47 #include <sys/socketvar.h>
48 #include <sys/sx.h>
49 #include <sys/sysctl.h>
50 #include <sys/systm.h>
51 #include <sys/uio.h>
52 
53 #include <net/if.h>
54 #include <net/route.h>
55 
56 #include <netinet/in.h>
57 #include <netinet/tcp.h>
58 
59 #include <sys/mchain.h>
60 
61 #include <netsmb/netbios.h>
62 
63 #include <netsmb/smb.h>
64 #include <netsmb/smb_conn.h>
65 #include <netsmb/smb_tran.h>
66 #include <netsmb/smb_trantcp.h>
67 #include <netsmb/smb_subr.h>
68 
69 #define M_NBDATA	M_PCB
70 
71 static int smb_tcpsndbuf = NB_SNDQ - 1;
72 static int smb_tcprcvbuf = NB_RCVQ - 1;
73 
74 SYSCTL_DECL(_net_smb);
75 SYSCTL_INT(_net_smb, OID_AUTO, tcpsndbuf, CTLFLAG_RW, &smb_tcpsndbuf, 0, "");
76 SYSCTL_INT(_net_smb, OID_AUTO, tcprcvbuf, CTLFLAG_RW, &smb_tcprcvbuf, 0, "");
77 
78 #define nb_sosend(so,m,flags,td) sosend(so, NULL, 0, m, 0, flags, td)
79 
80 static int  nbssn_recv(struct nbpcb *nbp, struct mbuf **mpp, int *lenp,
81 	u_int8_t *rpcodep, struct thread *td);
82 static int  smb_nbst_disconnect(struct smb_vc *vcp, struct thread *td);
83 
84 static int
85 nb_setsockopt_int(struct socket *so, int level, int name, int val)
86 {
87 	struct sockopt sopt;
88 
89 	bzero(&sopt, sizeof(sopt));
90 	sopt.sopt_level = level;
91 	sopt.sopt_name = name;
92 	sopt.sopt_val = &val;
93 	sopt.sopt_valsize = sizeof(val);
94 	return sosetopt(so, &sopt);
95 }
96 
97 static int
98 nb_intr(struct nbpcb *nbp, struct proc *p)
99 {
100 	return 0;
101 }
102 
103 static int
104 nb_upcall(struct socket *so, void *arg, int waitflag)
105 {
106 	struct nbpcb *nbp = arg;
107 
108 	if (arg == NULL || nbp->nbp_selectid == NULL)
109 		return (SU_OK);
110 	wakeup(nbp->nbp_selectid);
111 	return (SU_OK);
112 }
113 
114 static int
115 nb_sethdr(struct mbuf *m, u_int8_t type, u_int32_t len)
116 {
117 	u_int32_t *p = mtod(m, u_int32_t *);
118 
119 	*p = htonl((len & 0x1FFFF) | (type << 24));
120 	return 0;
121 }
122 
123 static int
124 nb_put_name(struct mbchain *mbp, struct sockaddr_nb *snb)
125 {
126 	int error;
127 	u_char seglen, *cp;
128 
129 	cp = snb->snb_name;
130 	if (*cp == 0)
131 		return EINVAL;
132 	NBDEBUG("[%s]\n", cp);
133 	for (;;) {
134 		seglen = (*cp) + 1;
135 		error = mb_put_mem(mbp, cp, seglen, MB_MSYSTEM);
136 		if (error)
137 			return error;
138 		if (seglen == 1)
139 			break;
140 		cp += seglen;
141 	}
142 	return 0;
143 }
144 
145 static int
146 nb_connect_in(struct nbpcb *nbp, struct sockaddr_in *to, struct thread *td)
147 {
148 	struct socket *so;
149 	int error, s;
150 
151 	error = socreate(AF_INET, &so, SOCK_STREAM, IPPROTO_TCP,
152 	    td->td_ucred, td);
153 	if (error)
154 		return error;
155 	nbp->nbp_tso = so;
156 	SOCKBUF_LOCK(&so->so_rcv);
157 	soupcall_set(so, SO_RCV, nb_upcall, nbp);
158 	SOCKBUF_UNLOCK(&so->so_rcv);
159 	so->so_rcv.sb_timeo = (5 * hz);
160 	so->so_snd.sb_timeo = (5 * hz);
161 	error = soreserve(so, nbp->nbp_sndbuf, nbp->nbp_rcvbuf);
162 	if (error)
163 		goto bad;
164 	nb_setsockopt_int(so, SOL_SOCKET, SO_KEEPALIVE, 1);
165 	nb_setsockopt_int(so, IPPROTO_TCP, TCP_NODELAY, 1);
166 	SOCKBUF_LOCK(&so->so_rcv);
167 	so->so_rcv.sb_flags &= ~SB_NOINTR;
168 	SOCKBUF_UNLOCK(&so->so_rcv);
169 	SOCKBUF_LOCK(&so->so_snd);
170 	so->so_snd.sb_flags &= ~SB_NOINTR;
171 	SOCKBUF_UNLOCK(&so->so_snd);
172 	error = soconnect(so, (struct sockaddr*)to, td);
173 	if (error)
174 		goto bad;
175 	s = splnet();
176 	while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
177 		tsleep(&so->so_timeo, PSOCK, "nbcon", 2 * hz);
178 		if ((so->so_state & SS_ISCONNECTING) && so->so_error == 0 &&
179 			(error = nb_intr(nbp, td->td_proc)) != 0) {
180 			so->so_state &= ~SS_ISCONNECTING;
181 			splx(s);
182 			goto bad;
183 		}
184 	}
185 	if (so->so_error) {
186 		error = so->so_error;
187 		so->so_error = 0;
188 		splx(s);
189 		goto bad;
190 	}
191 	splx(s);
192 	return 0;
193 bad:
194 	smb_nbst_disconnect(nbp->nbp_vc, td);
195 	return error;
196 }
197 
198 static int
199 nbssn_rq_request(struct nbpcb *nbp, struct thread *td)
200 {
201 	struct mbchain mb, *mbp = &mb;
202 	struct mdchain md, *mdp = &md;
203 	struct mbuf *m0;
204 	struct timeval tv;
205 	struct sockaddr_in sin;
206 	u_short port;
207 	u_int8_t rpcode;
208 	int error, rplen;
209 
210 	error = mb_init(mbp);
211 	if (error)
212 		return error;
213 	mb_put_uint32le(mbp, 0);
214 	nb_put_name(mbp, nbp->nbp_paddr);
215 	nb_put_name(mbp, nbp->nbp_laddr);
216 	nb_sethdr(mbp->mb_top, NB_SSN_REQUEST, mb_fixhdr(mbp) - 4);
217 	error = nb_sosend(nbp->nbp_tso, mbp->mb_top, 0, td);
218 	if (!error) {
219 		nbp->nbp_state = NBST_RQSENT;
220 	}
221 	mb_detach(mbp);
222 	mb_done(mbp);
223 	if (error)
224 		return error;
225 	TIMESPEC_TO_TIMEVAL(&tv, &nbp->nbp_timo);
226 	error = selsocket(nbp->nbp_tso, POLLIN, &tv, td);
227 	if (error == EWOULDBLOCK) {	/* Timeout */
228 		NBDEBUG("initial request timeout\n");
229 		return ETIMEDOUT;
230 	}
231 	if (error)			/* restart or interrupt */
232 		return error;
233 	error = nbssn_recv(nbp, &m0, &rplen, &rpcode, td);
234 	if (error) {
235 		NBDEBUG("recv() error %d\n", error);
236 		return error;
237 	}
238 	/*
239 	 * Process NETBIOS reply
240 	 */
241 	if (m0)
242 		md_initm(mdp, m0);
243 	error = 0;
244 	do {
245 		if (rpcode == NB_SSN_POSRESP) {
246 			nbp->nbp_state = NBST_SESSION;
247 			nbp->nbp_flags |= NBF_CONNECTED;
248 			break;
249 		}
250 		if (rpcode != NB_SSN_RTGRESP) {
251 			error = ECONNABORTED;
252 			break;
253 		}
254 		if (rplen != 6) {
255 			error = ECONNABORTED;
256 			break;
257 		}
258 		md_get_mem(mdp, (caddr_t)&sin.sin_addr, 4, MB_MSYSTEM);
259 		md_get_uint16(mdp, &port);
260 		sin.sin_port = port;
261 		nbp->nbp_state = NBST_RETARGET;
262 		smb_nbst_disconnect(nbp->nbp_vc, td);
263 		error = nb_connect_in(nbp, &sin, td);
264 		if (!error)
265 			error = nbssn_rq_request(nbp, td);
266 		if (error) {
267 			smb_nbst_disconnect(nbp->nbp_vc, td);
268 			break;
269 		}
270 	} while(0);
271 	if (m0)
272 		md_done(mdp);
273 	return error;
274 }
275 
276 static int
277 nbssn_recvhdr(struct nbpcb *nbp, int *lenp,
278 	u_int8_t *rpcodep, int flags, struct thread *td)
279 {
280 	struct socket *so = nbp->nbp_tso;
281 	struct uio auio;
282 	struct iovec aio;
283 	u_int32_t len;
284 	int error;
285 
286 	aio.iov_base = (caddr_t)&len;
287 	aio.iov_len = sizeof(len);
288 	auio.uio_iov = &aio;
289 	auio.uio_iovcnt = 1;
290 	auio.uio_segflg = UIO_SYSSPACE;
291 	auio.uio_rw = UIO_READ;
292 	auio.uio_offset = 0;
293 	auio.uio_resid = sizeof(len);
294 	auio.uio_td = td;
295 	error = soreceive(so, (struct sockaddr **)NULL, &auio,
296 	    (struct mbuf **)NULL, (struct mbuf **)NULL, &flags);
297 	if (error)
298 		return error;
299 	if (auio.uio_resid > 0) {
300 		SMBSDEBUG("short reply\n");
301 		return EPIPE;
302 	}
303 	len = ntohl(len);
304 	*rpcodep = (len >> 24) & 0xFF;
305 	len &= 0x1ffff;
306 	if (len > SMB_MAXPKTLEN) {
307 		SMBERROR("packet too long (%d)\n", len);
308 		return EFBIG;
309 	}
310 	*lenp = len;
311 	return 0;
312 }
313 
314 static int
315 nbssn_recv(struct nbpcb *nbp, struct mbuf **mpp, int *lenp,
316 	u_int8_t *rpcodep, struct thread *td)
317 {
318 	struct socket *so = nbp->nbp_tso;
319 	struct uio auio;
320 	struct mbuf *m, *tm, *im;
321 	u_int8_t rpcode;
322 	int len, resid;
323 	int error, rcvflg;
324 
325 	if (so == NULL)
326 		return ENOTCONN;
327 
328 	if (mpp)
329 		*mpp = NULL;
330 	m = NULL;
331 	for(;;) {
332 		/*
333 		 * Poll for a response header.
334 		 * If we don't have one waiting, return.
335 		 */
336 		len = 0;
337 		rpcode = 0;
338 		error = nbssn_recvhdr(nbp, &len, &rpcode, MSG_DONTWAIT, td);
339 		if ((so->so_state & (SS_ISDISCONNECTING | SS_ISDISCONNECTED)) ||
340 		    (so->so_rcv.sb_state & SBS_CANTRCVMORE)) {
341 			nbp->nbp_state = NBST_CLOSED;
342 			NBDEBUG("session closed by peer\n");
343 			return ECONNRESET;
344 		}
345 		if (error)
346 			return error;
347 		if (len == 0 && nbp->nbp_state != NBST_SESSION)
348 			break;
349 		/* no data, try again */
350 		if (rpcode == NB_SSN_KEEPALIVE)
351 			continue;
352 
353 		/*
354 		 * Loop, blocking, for data following the response header.
355 		 *
356 		 * Note that we can't simply block here with MSG_WAITALL for the
357 		 * entire response size, as it may be larger than the TCP
358 		 * slow-start window that the sender employs.  This will result
359 		 * in the sender stalling until the delayed ACK is sent, then
360 		 * resuming slow-start, resulting in very poor performance.
361 		 *
362 		 * Instead, we never request more than NB_SORECEIVE_CHUNK
363 		 * bytes at a time, resulting in an ack being pushed by
364 		 * the TCP code at the completion of each call.
365 		 */
366 		resid = len;
367 		while (resid > 0) {
368 			tm = NULL;
369 			rcvflg = MSG_WAITALL;
370 			bzero(&auio, sizeof(auio));
371 			auio.uio_resid = min(resid, NB_SORECEIVE_CHUNK);
372 			auio.uio_td = td;
373 			resid -= auio.uio_resid;
374 			/*
375 			 * Spin until we have collected everything in
376 			 * this chunk.
377 			 */
378 			do {
379 				rcvflg = MSG_WAITALL;
380 				error = soreceive(so, (struct sockaddr **)NULL,
381 				    &auio, &tm, (struct mbuf **)NULL, &rcvflg);
382 			} while (error == EWOULDBLOCK || error == EINTR ||
383 				 error == ERESTART);
384 			if (error)
385 				goto out;
386 			/* short return guarantees unhappiness */
387 			if (auio.uio_resid > 0) {
388 				SMBERROR("packet is shorter than expected\n");
389 				error = EPIPE;
390 				goto out;
391 			}
392 			/* append received chunk to previous chunk(s) */
393 			if (m == NULL) {
394 				m = tm;
395 			} else {
396 				/*
397 				 * Just glue the new chain on the end.
398 				 * Consumer will pullup as required.
399 				 */
400 				for (im = m; im->m_next != NULL; im = im->m_next)
401 					;
402 				im->m_next = tm;
403 			}
404 		}
405 		/* got a session/message packet? */
406 		if (nbp->nbp_state == NBST_SESSION &&
407 		    rpcode == NB_SSN_MESSAGE)
408 			break;
409 		/* drop packet and try for another */
410 		NBDEBUG("non-session packet %x\n", rpcode);
411 		if (m) {
412 			m_freem(m);
413 			m = NULL;
414 		}
415 	}
416 
417 out:
418 	if (error) {
419 		if (m)
420 			m_freem(m);
421 		return error;
422 	}
423 	if (mpp)
424 		*mpp = m;
425 	else
426 		m_freem(m);
427 	*lenp = len;
428 	*rpcodep = rpcode;
429 	return 0;
430 }
431 
432 /*
433  * SMB transport interface
434  */
435 static int
436 smb_nbst_create(struct smb_vc *vcp, struct thread *td)
437 {
438 	struct nbpcb *nbp;
439 
440 	nbp = malloc(sizeof *nbp, M_NBDATA, M_WAITOK);
441 	bzero(nbp, sizeof *nbp);
442 	nbp->nbp_timo.tv_sec = 15;	/* XXX: sysctl ? */
443 	nbp->nbp_state = NBST_CLOSED;
444 	nbp->nbp_vc = vcp;
445 	nbp->nbp_sndbuf = smb_tcpsndbuf;
446 	nbp->nbp_rcvbuf = smb_tcprcvbuf;
447 	vcp->vc_tdata = nbp;
448 	return 0;
449 }
450 
451 static int
452 smb_nbst_done(struct smb_vc *vcp, struct thread *td)
453 {
454 	struct nbpcb *nbp = vcp->vc_tdata;
455 
456 	if (nbp == NULL)
457 		return ENOTCONN;
458 	smb_nbst_disconnect(vcp, td);
459 	if (nbp->nbp_laddr)
460 		free(nbp->nbp_laddr, M_SONAME);
461 	if (nbp->nbp_paddr)
462 		free(nbp->nbp_paddr, M_SONAME);
463 	free(nbp, M_NBDATA);
464 	return 0;
465 }
466 
467 static int
468 smb_nbst_bind(struct smb_vc *vcp, struct sockaddr *sap, struct thread *td)
469 {
470 	struct nbpcb *nbp = vcp->vc_tdata;
471 	struct sockaddr_nb *snb;
472 	int error, slen;
473 
474 	NBDEBUG("\n");
475 	error = EINVAL;
476 	do {
477 		if (nbp->nbp_flags & NBF_LOCADDR)
478 			break;
479 		/*
480 		 * It is possible to create NETBIOS name in the kernel,
481 		 * but nothing prevents us to do it in the user space.
482 		 */
483 		if (sap == NULL)
484 			break;
485 		slen = sap->sa_len;
486 		if (slen < NB_MINSALEN)
487 			break;
488 		snb = (struct sockaddr_nb*)sodupsockaddr(sap, M_WAITOK);
489 		if (snb == NULL) {
490 			error = ENOMEM;
491 			break;
492 		}
493 		nbp->nbp_laddr = snb;
494 		nbp->nbp_flags |= NBF_LOCADDR;
495 		error = 0;
496 	} while(0);
497 	return error;
498 }
499 
500 static int
501 smb_nbst_connect(struct smb_vc *vcp, struct sockaddr *sap, struct thread *td)
502 {
503 	struct nbpcb *nbp = vcp->vc_tdata;
504 	struct sockaddr_in sin;
505 	struct sockaddr_nb *snb;
506 	struct timespec ts1, ts2;
507 	int error, slen;
508 
509 	NBDEBUG("\n");
510 	if (nbp->nbp_tso != NULL)
511 		return EISCONN;
512 	if (nbp->nbp_laddr == NULL)
513 		return EINVAL;
514 	slen = sap->sa_len;
515 	if (slen < NB_MINSALEN)
516 		return EINVAL;
517 	if (nbp->nbp_paddr) {
518 		free(nbp->nbp_paddr, M_SONAME);
519 		nbp->nbp_paddr = NULL;
520 	}
521 	snb = (struct sockaddr_nb*)sodupsockaddr(sap, M_WAITOK);
522 	if (snb == NULL)
523 		return ENOMEM;
524 	nbp->nbp_paddr = snb;
525 	sin = snb->snb_addrin;
526 	getnanotime(&ts1);
527 	error = nb_connect_in(nbp, &sin, td);
528 	if (error)
529 		return error;
530 	getnanotime(&ts2);
531 	timespecsub(&ts2, &ts1);
532 	if (ts2.tv_sec == 0 && ts2.tv_sec == 0)
533 		ts2.tv_sec = 1;
534 	nbp->nbp_timo = ts2;
535 	timespecadd(&nbp->nbp_timo, &ts2);
536 	timespecadd(&nbp->nbp_timo, &ts2);
537 	timespecadd(&nbp->nbp_timo, &ts2);	/*  * 4 */
538 	error = nbssn_rq_request(nbp, td);
539 	if (error)
540 		smb_nbst_disconnect(vcp, td);
541 	return error;
542 }
543 
544 static int
545 smb_nbst_disconnect(struct smb_vc *vcp, struct thread *td)
546 {
547 	struct nbpcb *nbp = vcp->vc_tdata;
548 	struct socket *so;
549 
550 	if (nbp == NULL || nbp->nbp_tso == NULL)
551 		return ENOTCONN;
552 	if ((so = nbp->nbp_tso) != NULL) {
553 		nbp->nbp_flags &= ~NBF_CONNECTED;
554 		nbp->nbp_tso = (struct socket *)NULL;
555 		soshutdown(so, 2);
556 		soclose(so);
557 	}
558 	if (nbp->nbp_state != NBST_RETARGET) {
559 		nbp->nbp_state = NBST_CLOSED;
560 	}
561 	return 0;
562 }
563 
564 static int
565 smb_nbst_send(struct smb_vc *vcp, struct mbuf *m0, struct thread *td)
566 {
567 	struct nbpcb *nbp = vcp->vc_tdata;
568 	int error;
569 
570 	if (nbp->nbp_state != NBST_SESSION) {
571 		error = ENOTCONN;
572 		goto abort;
573 	}
574 	M_PREPEND(m0, 4, M_WAIT);
575 	nb_sethdr(m0, NB_SSN_MESSAGE, m_fixhdr(m0) - 4);
576 	error = nb_sosend(nbp->nbp_tso, m0, 0, td);
577 	return error;
578 abort:
579 	if (m0)
580 		m_freem(m0);
581 	return error;
582 }
583 
584 
585 static int
586 smb_nbst_recv(struct smb_vc *vcp, struct mbuf **mpp, struct thread *td)
587 {
588 	struct nbpcb *nbp = vcp->vc_tdata;
589 	u_int8_t rpcode;
590 	int error, rplen;
591 
592 	nbp->nbp_flags |= NBF_RECVLOCK;
593 	error = nbssn_recv(nbp, mpp, &rplen, &rpcode, td);
594 	nbp->nbp_flags &= ~NBF_RECVLOCK;
595 	return error;
596 }
597 
598 static void
599 smb_nbst_timo(struct smb_vc *vcp)
600 {
601 	return;
602 }
603 
604 static void
605 smb_nbst_intr(struct smb_vc *vcp)
606 {
607 	struct nbpcb *nbp = vcp->vc_tdata;
608 
609 	if (nbp == NULL || nbp->nbp_tso == NULL)
610 		return;
611 	sorwakeup(nbp->nbp_tso);
612 	sowwakeup(nbp->nbp_tso);
613 }
614 
615 static int
616 smb_nbst_getparam(struct smb_vc *vcp, int param, void *data)
617 {
618 	struct nbpcb *nbp = vcp->vc_tdata;
619 
620 	switch (param) {
621 	    case SMBTP_SNDSZ:
622 		*(int*)data = nbp->nbp_sndbuf;
623 		break;
624 	    case SMBTP_RCVSZ:
625 		*(int*)data = nbp->nbp_rcvbuf;
626 		break;
627 	    case SMBTP_TIMEOUT:
628 		*(struct timespec*)data = nbp->nbp_timo;
629 		break;
630 	    default:
631 		return EINVAL;
632 	}
633 	return 0;
634 }
635 
636 static int
637 smb_nbst_setparam(struct smb_vc *vcp, int param, void *data)
638 {
639 	struct nbpcb *nbp = vcp->vc_tdata;
640 
641 	switch (param) {
642 	    case SMBTP_SELECTID:
643 		nbp->nbp_selectid = data;
644 		break;
645 	    default:
646 		return EINVAL;
647 	}
648 	return 0;
649 }
650 
651 /*
652  * Check for fatal errors
653  */
654 static int
655 smb_nbst_fatal(struct smb_vc *vcp, int error)
656 {
657 	switch (error) {
658 	    case ENOTCONN:
659 	    case ENETRESET:
660 	    case ECONNABORTED:
661 		return 1;
662 	}
663 	return 0;
664 }
665 
666 
667 struct smb_tran_desc smb_tran_nbtcp_desc = {
668 	SMBT_NBTCP,
669 	smb_nbst_create, smb_nbst_done,
670 	smb_nbst_bind, smb_nbst_connect, smb_nbst_disconnect,
671 	smb_nbst_send, smb_nbst_recv,
672 	smb_nbst_timo, smb_nbst_intr,
673 	smb_nbst_getparam, smb_nbst_setparam,
674 	smb_nbst_fatal
675 };
676 
677