1/*
2 * Copyright (c) 1997-2014 Erez Zadok
3 * Copyright (c) 1990 Jan-Simon Pendry
4 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
5 * Copyright (c) 1990 The Regents of the University of California.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Jan-Simon Pendry at Imperial College, London.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 *
36 * File: am-utils/amd/ops_nfs.c
37 *
38 */
39
40/*
41 * Network file system
42 */
43
44#ifdef HAVE_CONFIG_H
45# include <config.h>
46#endif /* HAVE_CONFIG_H */
47#include <am_defs.h>
48#include <amd.h>
49
50/*
51 * Convert from nfsstat to UN*X error code
52 */
53#define unx_error(e)	((int)(e))
54
55/*
56 * FH_TTL is the time a file handle will remain in the cache since
57 * last being used.  If the file handle becomes invalid, then it
58 * will be flushed anyway.
59 */
60#define	FH_TTL			(5 * 60) /* five minutes */
61#define	FH_TTL_ERROR		(30) /* 30 seconds */
62#define	FHID_ALLOC()		(++fh_id)
63
64/*
65 * The NFS layer maintains a cache of file handles.
66 * This is *fundamental* to the implementation and
67 * also allows quick remounting when a filesystem
68 * is accessed soon after timing out.
69 *
70 * The NFS server layer knows to flush this cache
71 * when a server goes down so avoiding stale handles.
72 *
73 * Each cache entry keeps a hard reference to
74 * the corresponding server.  This ensures that
75 * the server keepalive information is maintained.
76 *
77 * The copy of the sockaddr_in here is taken so
78 * that the port can be twiddled to talk to mountd
79 * instead of portmap or the NFS server as used
80 * elsewhere.
81 * The port# is flushed if a server goes down.
82 * The IP address is never flushed - we assume
83 * that the address of a mounted machine never
84 * changes.  If it does, then you have other
85 * problems...
86 */
87typedef struct fh_cache fh_cache;
88struct fh_cache {
89  qelem			fh_q;		/* List header */
90  wchan_t		fh_wchan;	/* Wait channel */
91  int			fh_error;	/* Valid data? */
92  int			fh_id;		/* Unique id */
93  int			fh_cid;		/* Callout id */
94  u_long		fh_nfs_version;	/* highest NFS version on host */
95  am_nfs_handle_t	fh_nfs_handle;	/* Handle on filesystem */
96  int			fh_status;	/* Status of last rpc */
97  struct sockaddr_in	fh_sin;		/* Address of mountd */
98  fserver		*fh_fs;		/* Server holding filesystem */
99  char			*fh_path;	/* Filesystem on host */
100};
101
102/* forward definitions */
103static int nfs_init(mntfs *mf);
104static char *nfs_match(am_opts *fo);
105static int nfs_mount(am_node *am, mntfs *mf);
106static int nfs_umount(am_node *am, mntfs *mf);
107static void nfs_umounted(mntfs *mf);
108static int call_mountd(fh_cache *fp, u_long proc, fwd_fun f, wchan_t wchan);
109static int webnfs_lookup(fh_cache *fp, fwd_fun f, wchan_t wchan);
110static int fh_id = 0;
111
112/*
113 * clamp the filehandle version to 3, so that we can fail back to nfsv3
114 * since nfsv4 does not have file handles
115 */
116#define SET_FH_VERSION(fs) \
117    (fs)->fs_version > NFS_VERSION3 ? NFS_VERSION3 : (fs)->fs_version;
118
119/* globals */
120AUTH *nfs_auth;
121qelem fh_head = {&fh_head, &fh_head};
122
123/*
124 * Network file system operations
125 */
126am_ops nfs_ops =
127{
128  "nfs",
129  nfs_match,
130  nfs_init,
131  nfs_mount,
132  nfs_umount,
133  amfs_error_lookup_child,
134  amfs_error_mount_child,
135  amfs_error_readdir,
136  0,				/* nfs_readlink */
137  0,				/* nfs_mounted */
138  nfs_umounted,
139  find_nfs_srvr,
140  0,				/* nfs_get_wchan */
141  FS_MKMNT | FS_BACKGROUND | FS_AMQINFO,	/* nfs_fs_flags */
142#ifdef HAVE_FS_AUTOFS
143  AUTOFS_NFS_FS_FLAGS,
144#endif /* HAVE_FS_AUTOFS */
145};
146
147
148static fh_cache *
149find_nfs_fhandle_cache(opaque_t arg, int done)
150{
151  fh_cache *fp, *fp2 = NULL;
152  int id = (long) arg;		/* for 64-bit archs */
153
154  ITER(fp, fh_cache, &fh_head) {
155    if (fp->fh_id == id) {
156      fp2 = fp;
157      break;
158    }
159  }
160
161  if (fp2) {
162    dlog("fh cache gives fp %#lx, fs %s", (unsigned long) fp2, fp2->fh_path);
163  } else {
164    dlog("fh cache search failed");
165  }
166
167  if (fp2 && !done) {
168    fp2->fh_error = ETIMEDOUT;
169    return 0;
170  }
171
172  return fp2;
173}
174
175
176/*
177 * Called when a filehandle appears via the mount protocol
178 */
179static void
180got_nfs_fh_mount(voidp pkt, int len, struct sockaddr_in *sa, struct sockaddr_in *ia, opaque_t arg, int done)
181{
182  fh_cache *fp;
183  struct fhstatus res;
184#ifdef HAVE_FS_NFS3
185  struct am_mountres3 res3;
186#endif /* HAVE_FS_NFS3 */
187
188  fp = find_nfs_fhandle_cache(arg, done);
189  if (!fp)
190    return;
191
192  /*
193   * retrieve the correct RPC reply for the file handle, based on the
194   * NFS protocol version.
195   */
196#ifdef HAVE_FS_NFS3
197  if (fp->fh_nfs_version == NFS_VERSION3) {
198    memset(&res3, 0, sizeof(res3));
199    fp->fh_error = pickup_rpc_reply(pkt, len, (voidp) &res3,
200				    (XDRPROC_T_TYPE) xdr_am_mountres3);
201    fp->fh_status = unx_error(res3.fhs_status);
202    memset(&fp->fh_nfs_handle.v3, 0, sizeof(am_nfs_fh3));
203    fp->fh_nfs_handle.v3.am_fh3_length = res3.mountres3_u.mountinfo.fhandle.fhandle3_len;
204    memmove(fp->fh_nfs_handle.v3.am_fh3_data,
205	    res3.mountres3_u.mountinfo.fhandle.fhandle3_val,
206	    fp->fh_nfs_handle.v3.am_fh3_length);
207
208    XFREE(res3.mountres3_u.mountinfo.fhandle.fhandle3_val);
209    if (res3.mountres3_u.mountinfo.auth_flavors.auth_flavors_val)
210      XFREE(res3.mountres3_u.mountinfo.auth_flavors.auth_flavors_val);
211  } else {
212#endif /* HAVE_FS_NFS3 */
213    memset(&res, 0, sizeof(res));
214    fp->fh_error = pickup_rpc_reply(pkt, len, (voidp) &res,
215				    (XDRPROC_T_TYPE) xdr_fhstatus);
216    fp->fh_status = unx_error(res.fhs_status);
217    memmove(&fp->fh_nfs_handle.v2, &res.fhs_fh, NFS_FHSIZE);
218#ifdef HAVE_FS_NFS3
219  }
220#endif /* HAVE_FS_NFS3 */
221
222  if (!fp->fh_error) {
223    dlog("got filehandle for %s:%s", fp->fh_fs->fs_host, fp->fh_path);
224  } else {
225    plog(XLOG_USER, "filehandle denied for %s:%s", fp->fh_fs->fs_host, fp->fh_path);
226    /*
227     * Force the error to be EACCES. It's debatable whether it should be
228     * ENOENT instead, but the server really doesn't give us any clues, and
229     * EACCES is more in line with the "filehandle denied" message.
230     */
231    fp->fh_error = EACCES;
232  }
233
234  /*
235   * Wakeup anything sleeping on this filehandle
236   */
237  if (fp->fh_wchan) {
238    dlog("Calling wakeup on %#lx", (unsigned long) fp->fh_wchan);
239    wakeup(fp->fh_wchan);
240  }
241}
242
243
244/*
245 * Called when a filehandle appears via WebNFS
246 */
247static void
248got_nfs_fh_webnfs(voidp pkt, int len, struct sockaddr_in *sa, struct sockaddr_in *ia, opaque_t arg, int done)
249{
250  fh_cache *fp;
251  nfsdiropres res;
252#ifdef HAVE_FS_NFS3
253  am_LOOKUP3res res3;
254#endif /* HAVE_FS_NFS3 */
255
256  fp = find_nfs_fhandle_cache(arg, done);
257  if (!fp)
258    return;
259
260  /*
261   * retrieve the correct RPC reply for the file handle, based on the
262   * NFS protocol version.
263   */
264#ifdef HAVE_FS_NFS3
265  if (fp->fh_nfs_version == NFS_VERSION3) {
266    memset(&res3, 0, sizeof(res3));
267    fp->fh_error = pickup_rpc_reply(pkt, len, (voidp) &res3,
268				    (XDRPROC_T_TYPE) xdr_am_LOOKUP3res);
269    fp->fh_status = unx_error(res3.status);
270    memset(&fp->fh_nfs_handle.v3, 0, sizeof(am_nfs_fh3));
271    fp->fh_nfs_handle.v3.am_fh3_length = res3.res_u.ok.object.am_fh3_length;
272    memmove(fp->fh_nfs_handle.v3.am_fh3_data,
273	    res3.res_u.ok.object.am_fh3_data,
274	    fp->fh_nfs_handle.v3.am_fh3_length);
275  } else {
276#endif /* HAVE_FS_NFS3 */
277    memset(&res, 0, sizeof(res));
278    fp->fh_error = pickup_rpc_reply(pkt, len, (voidp) &res,
279				    (XDRPROC_T_TYPE) xdr_diropres);
280    fp->fh_status = unx_error(res.dr_status);
281    memmove(&fp->fh_nfs_handle.v2, &res.dr_u.dr_drok_u.drok_fhandle, NFS_FHSIZE);
282#ifdef HAVE_FS_NFS3
283  }
284#endif /* HAVE_FS_NFS3 */
285
286  if (!fp->fh_error) {
287    dlog("got filehandle for %s:%s", fp->fh_fs->fs_host, fp->fh_path);
288  } else {
289    plog(XLOG_USER, "filehandle denied for %s:%s", fp->fh_fs->fs_host, fp->fh_path);
290    /*
291     * Force the error to be EACCES. It's debatable whether it should be
292     * ENOENT instead, but the server really doesn't give us any clues, and
293     * EACCES is more in line with the "filehandle denied" message.
294     */
295    fp->fh_error = EACCES;
296  }
297
298  /*
299   * Wakeup anything sleeping on this filehandle
300   */
301  if (fp->fh_wchan) {
302    dlog("Calling wakeup on %#lx", (unsigned long) fp->fh_wchan);
303    wakeup(fp->fh_wchan);
304  }
305}
306
307
308void
309flush_nfs_fhandle_cache(fserver *fs)
310{
311  fh_cache *fp;
312
313  ITER(fp, fh_cache, &fh_head) {
314    if (fp->fh_fs == fs || fs == NULL) {
315      /*
316       * Only invalidate port info for non-WebNFS servers
317       */
318      if (!(fp->fh_fs->fs_flags & FSF_WEBNFS))
319	fp->fh_sin.sin_port = (u_short) 0;
320      fp->fh_error = -1;
321    }
322  }
323}
324
325
326static void
327discard_fh(opaque_t arg)
328{
329  fh_cache *fp = (fh_cache *) arg;
330
331  rem_que(&fp->fh_q);
332  if (fp->fh_fs) {
333    dlog("Discarding filehandle for %s:%s", fp->fh_fs->fs_host, fp->fh_path);
334    free_srvr(fp->fh_fs);
335  }
336  XFREE(fp->fh_path);
337  XFREE(fp);
338}
339
340
341/*
342 * Determine the file handle for a node
343 */
344static int
345prime_nfs_fhandle_cache(char *path, fserver *fs, am_nfs_handle_t *fhbuf, mntfs *mf)
346{
347  fh_cache *fp, *fp_save = NULL;
348  int error;
349  int reuse_id = FALSE;
350
351  dlog("Searching cache for %s:%s", fs->fs_host, path);
352
353  /*
354   * First search the cache
355   */
356  ITER(fp, fh_cache, &fh_head) {
357    if (fs != fp->fh_fs  ||  !STREQ(path, fp->fh_path))
358      continue;			/* skip to next ITER item */
359    /* else we got a match */
360    switch (fp->fh_error) {
361    case 0:
362      plog(XLOG_INFO, "prime_nfs_fhandle_cache: NFS version %d", (int) fp->fh_nfs_version);
363
364      error = fp->fh_error = fp->fh_status;
365
366      if (error == 0) {
367	if (mf->mf_flags & MFF_NFS_SCALEDOWN) {
368	  fp_save = fp;
369	  /* XXX: why reuse the ID? */
370	  reuse_id = TRUE;
371	  break;
372	}
373
374	if (fhbuf) {
375#ifdef HAVE_FS_NFS3
376	  if (fp->fh_nfs_version == NFS_VERSION3) {
377	    memmove((voidp) &(fhbuf->v3), (voidp) &(fp->fh_nfs_handle.v3),
378		    sizeof(fp->fh_nfs_handle.v3));
379	  } else
380#endif /* HAVE_FS_NFS3 */
381	    {
382	      memmove((voidp) &(fhbuf->v2), (voidp) &(fp->fh_nfs_handle.v2),
383		      sizeof(fp->fh_nfs_handle.v2));
384	    }
385	}
386	if (fp->fh_cid)
387	  untimeout(fp->fh_cid);
388	fp->fh_cid = timeout(FH_TTL, discard_fh, (opaque_t) fp);
389      } else if (error == EACCES) {
390	/*
391	 * Now decode the file handle return code.
392	 */
393	plog(XLOG_INFO, "Filehandle denied for \"%s:%s\"",
394	     fs->fs_host, path);
395      } else {
396	errno = error;	/* XXX */
397	plog(XLOG_INFO, "Filehandle error for \"%s:%s\": %m",
398	     fs->fs_host, path);
399      }
400
401      /*
402       * The error was returned from the remote mount daemon.
403       * Policy: this error will be cached for now...
404       */
405      return error;
406
407    case -1:
408      /*
409       * Still thinking about it, but we can re-use.
410       */
411      fp_save = fp;
412      reuse_id = TRUE;
413      break;
414
415    default:
416      /*
417       * Return the error.
418       * Policy: make sure we recompute if required again
419       * in case this was caused by a network failure.
420       * This can thrash mountd's though...  If you find
421       * your mountd going slowly then:
422       * 1.  Add a fork() loop to main.
423       * 2.  Remove the call to innetgr() and don't use
424       *     netgroups, especially if you don't use YP.
425       */
426      error = fp->fh_error;
427      fp->fh_error = -1;
428      return error;
429    }	/* end of switch statement */
430  } /* end of ITER loop */
431
432  /*
433   * Not in cache
434   */
435  if (fp_save) {
436    fp = fp_save;
437    /*
438     * Re-use existing slot
439     */
440    untimeout(fp->fh_cid);
441    free_srvr(fp->fh_fs);
442    XFREE(fp->fh_path);
443  } else {
444    fp = ALLOC(struct fh_cache);
445    memset((voidp) fp, 0, sizeof(struct fh_cache));
446    ins_que(&fp->fh_q, &fh_head);
447  }
448  if (!reuse_id)
449    fp->fh_id = FHID_ALLOC();
450  fp->fh_wchan = get_mntfs_wchan(mf);
451  fp->fh_error = -1;
452  fp->fh_cid = timeout(FH_TTL, discard_fh, (opaque_t) fp);
453
454  /*
455   * If fs->fs_ip is null, remote server is probably down.
456   */
457  if (!fs->fs_ip) {
458    /* Mark the fileserver down and invalid again */
459    fs->fs_flags &= ~FSF_VALID;
460    fs->fs_flags |= FSF_DOWN;
461    error = AM_ERRNO_HOST_DOWN;
462    return error;
463  }
464
465  /*
466   * Either fp has been freshly allocated or the address has changed.
467   * Initialize address and nfs version.  Don't try to re-use the port
468   * information unless using WebNFS where the port is fixed either by
469   * the spec or the "port" mount option.
470   */
471  if (fp->fh_sin.sin_addr.s_addr != fs->fs_ip->sin_addr.s_addr) {
472    fp->fh_sin = *fs->fs_ip;
473    if (!(mf->mf_flags & MFF_WEBNFS))
474	fp->fh_sin.sin_port = 0;
475    fp->fh_nfs_version = SET_FH_VERSION(fs);
476  }
477
478  fp->fh_fs = dup_srvr(fs);
479  fp->fh_path = xstrdup(path);
480
481  if (mf->mf_flags & MFF_WEBNFS)
482    error = webnfs_lookup(fp, got_nfs_fh_webnfs, get_mntfs_wchan(mf));
483  else
484    error = call_mountd(fp, MOUNTPROC_MNT, got_nfs_fh_mount, get_mntfs_wchan(mf));
485  if (error) {
486    /*
487     * Local error - cache for a short period
488     * just to prevent thrashing.
489     */
490    untimeout(fp->fh_cid);
491    fp->fh_cid = timeout(error < 0 ? 2 * ALLOWED_MOUNT_TIME : FH_TTL_ERROR,
492			 discard_fh, (opaque_t) fp);
493    fp->fh_error = error;
494  } else {
495    error = fp->fh_error;
496  }
497
498  return error;
499}
500
501
502int
503make_nfs_auth(void)
504{
505  AUTH_CREATE_GIDLIST_TYPE group_wheel = 0;
506
507  /* Some NFS mounts (particularly cross-domain) require FQDNs to succeed */
508
509#ifdef HAVE_TRANSPORT_TYPE_TLI
510  if (gopt.flags & CFM_FULLY_QUALIFIED_HOSTS) {
511    plog(XLOG_INFO, "Using NFS auth for FQHN \"%s\"", hostd);
512    nfs_auth = authsys_create(hostd, 0, 0, 1, &group_wheel);
513  } else {
514    nfs_auth = authsys_create_default();
515  }
516#else /* not HAVE_TRANSPORT_TYPE_TLI */
517  if (gopt.flags & CFM_FULLY_QUALIFIED_HOSTS) {
518    plog(XLOG_INFO, "Using NFS auth for FQHN \"%s\"", hostd);
519    nfs_auth = authunix_create(hostd, 0, 0, 1, &group_wheel);
520  } else {
521    nfs_auth = authunix_create_default();
522  }
523#endif /* not HAVE_TRANSPORT_TYPE_TLI */
524
525  if (!nfs_auth)
526    return ENOBUFS;
527
528  return 0;
529}
530
531
532static int
533call_mountd(fh_cache *fp, u_long proc, fwd_fun fun, wchan_t wchan)
534{
535  struct rpc_msg mnt_msg;
536  int len;
537  char iobuf[UDPMSGSIZE];
538  int error;
539  u_long mnt_version;
540
541  if (!nfs_auth) {
542    error = make_nfs_auth();
543    if (error)
544      return error;
545  }
546
547  if (fp->fh_sin.sin_port == 0) {
548    u_short mountd_port;
549    error = get_mountd_port(fp->fh_fs, &mountd_port, wchan);
550    if (error)
551      return error;
552    fp->fh_sin.sin_port = mountd_port;
553    dlog("%s: New %d mountd port", __func__, fp->fh_sin.sin_port);
554  } else
555    dlog("%s: Already had %d mountd port", __func__, fp->fh_sin.sin_port);
556
557  /* find the right version of the mount protocol */
558#ifdef HAVE_FS_NFS3
559  if (fp->fh_nfs_version == NFS_VERSION3)
560    mnt_version = AM_MOUNTVERS3;
561  else
562#endif /* HAVE_FS_NFS3 */
563    mnt_version = MOUNTVERS;
564  plog(XLOG_INFO, "call_mountd: NFS version %d, mount version %d",
565       (int) fp->fh_nfs_version, (int) mnt_version);
566
567  rpc_msg_init(&mnt_msg, MOUNTPROG, mnt_version, MOUNTPROC_NULL);
568  len = make_rpc_packet(iobuf,
569			sizeof(iobuf),
570			proc,
571			&mnt_msg,
572			(voidp) &fp->fh_path,
573			(XDRPROC_T_TYPE) xdr_nfspath,
574			nfs_auth);
575
576  if (len > 0) {
577    error = fwd_packet(MK_RPC_XID(RPC_XID_MOUNTD, fp->fh_id),
578		       iobuf,
579		       len,
580		       &fp->fh_sin,
581		       &fp->fh_sin,
582		       (opaque_t) ((long) fp->fh_id), /* cast to long needed for 64-bit archs */
583		       fun);
584  } else {
585    error = -len;
586  }
587
588  /*
589   * It may be the case that we're sending to the wrong MOUNTD port.  This
590   * occurs if mountd is restarted on the server after the port has been
591   * looked up and stored in the filehandle cache somewhere.  The correct
592   * solution, if we're going to cache port numbers is to catch the ICMP
593   * port unreachable reply from the server and cause the portmap request
594   * to be redone.  The quick solution here is to invalidate the MOUNTD
595   * port.
596   */
597  fp->fh_sin.sin_port = 0;
598
599  return error;
600}
601
602
603static int
604webnfs_lookup(fh_cache *fp, fwd_fun fun, wchan_t wchan)
605{
606  struct rpc_msg wnfs_msg;
607  int len;
608  char iobuf[UDPMSGSIZE];
609  int error;
610  u_long proc;
611  XDRPROC_T_TYPE xdr_fn;
612  voidp argp;
613  nfsdiropargs args;
614#ifdef HAVE_FS_NFS3
615  am_LOOKUP3args args3;
616#endif /* HAVE_FS_NFS3 */
617  char *wnfs_path;
618  size_t l;
619
620  if (!nfs_auth) {
621    error = make_nfs_auth();
622    if (error)
623      return error;
624  }
625
626  if (fp->fh_sin.sin_port == 0) {
627    /* FIXME: wrong, don't discard sin_port in the first place for WebNFS. */
628    plog(XLOG_WARNING, "webnfs_lookup: port == 0 for nfs on %s, fixed",
629	 fp->fh_fs->fs_host);
630    fp->fh_sin.sin_port = htons(NFS_PORT);
631  }
632
633  /*
634   * Use native path like the rest of amd (cf. RFC 2054, 6.1).
635   */
636  l = strlen(fp->fh_path) + 2;
637  wnfs_path = (char *) xmalloc(l);
638  wnfs_path[0] = 0x80;
639  xstrlcpy(wnfs_path + 1, fp->fh_path, l - 1);
640
641  /* find the right program and lookup procedure */
642#ifdef HAVE_FS_NFS3
643  if (fp->fh_nfs_version == NFS_VERSION3) {
644    proc = AM_NFSPROC3_LOOKUP;
645    xdr_fn = (XDRPROC_T_TYPE) xdr_am_LOOKUP3args;
646    argp = &args3;
647    /* WebNFS public file handle */
648    args3.what.dir.am_fh3_length = 0;
649    args3.what.name = wnfs_path;
650  } else {
651#endif /* HAVE_FS_NFS3 */
652    proc = NFSPROC_LOOKUP;
653    xdr_fn = (XDRPROC_T_TYPE) xdr_diropargs;
654    argp = &args;
655    /* WebNFS public file handle */
656    memset(&args.da_fhandle, 0, NFS_FHSIZE);
657    args.da_name = wnfs_path;
658#ifdef HAVE_FS_NFS3
659  }
660#endif /* HAVE_FS_NFS3 */
661
662  plog(XLOG_INFO, "webnfs_lookup: NFS version %d", (int) fp->fh_nfs_version);
663
664  rpc_msg_init(&wnfs_msg, NFS_PROGRAM, fp->fh_nfs_version, proc);
665  len = make_rpc_packet(iobuf,
666			sizeof(iobuf),
667			proc,
668			&wnfs_msg,
669			argp,
670			(XDRPROC_T_TYPE) xdr_fn,
671			nfs_auth);
672
673  if (len > 0) {
674    error = fwd_packet(MK_RPC_XID(RPC_XID_WEBNFS, fp->fh_id),
675		       iobuf,
676		       len,
677		       &fp->fh_sin,
678		       &fp->fh_sin,
679		       (opaque_t) ((long) fp->fh_id), /* cast to long needed for 64-bit archs */
680		       fun);
681  } else {
682    error = -len;
683  }
684
685  XFREE(wnfs_path);
686  return error;
687}
688
689
690/*
691 * NFS needs the local filesystem, remote filesystem
692 * remote hostname.
693 * Local filesystem defaults to remote and vice-versa.
694 */
695static char *
696nfs_match(am_opts *fo)
697{
698  char *xmtab;
699  size_t l;
700
701  if (fo->opt_fs && !fo->opt_rfs)
702    fo->opt_rfs = fo->opt_fs;
703  if (!fo->opt_rfs) {
704    plog(XLOG_USER, "nfs: no remote filesystem specified");
705    return NULL;
706  }
707  if (!fo->opt_rhost) {
708    plog(XLOG_USER, "nfs: no remote host specified");
709    return NULL;
710  }
711
712  /*
713   * Determine magic cookie to put in mtab
714   */
715  l = strlen(fo->opt_rhost) + strlen(fo->opt_rfs) + 2;
716  xmtab = (char *) xmalloc(l);
717  xsnprintf(xmtab, l, "%s:%s", fo->opt_rhost, fo->opt_rfs);
718  dlog("NFS: mounting remote server \"%s\", remote fs \"%s\" on \"%s\"",
719       fo->opt_rhost, fo->opt_rfs, fo->opt_fs);
720
721  return xmtab;
722}
723
724
725/*
726 * Initialize am structure for nfs
727 */
728static int
729nfs_init(mntfs *mf)
730{
731  int error;
732  am_nfs_handle_t fhs;
733  char *colon;
734
735#ifdef NO_FALLBACK
736  /*
737   * We don't need file handles for NFS version 4, but we can fall back to
738   * version 3, so we allocate anyway
739   */
740#ifdef HAVE_FS_NFS4
741  if (mf->mf_server->fs_version == NFS_VERSION4)
742    return 0;
743#endif /* HAVE_FS_NFS4 */
744#endif /* NO_FALLBACK */
745
746  if (mf->mf_private) {
747    if (mf->mf_flags & MFF_NFS_SCALEDOWN) {
748      fserver *fs;
749
750      /* tell remote mountd that we're done with this filehandle */
751      mf->mf_ops->umounted(mf);
752
753      mf->mf_prfree(mf->mf_private);
754      mf->mf_private = NULL;
755      mf->mf_prfree = NULL;
756
757      fs = mf->mf_ops->ffserver(mf);
758      free_srvr(mf->mf_server);
759      mf->mf_server = fs;
760    } else
761      return 0;
762  }
763
764  colon = strchr(mf->mf_info, ':');
765  if (colon == 0)
766    return ENOENT;
767
768  error = prime_nfs_fhandle_cache(colon + 1, mf->mf_server, &fhs, mf);
769  if (!error) {
770    mf->mf_private = (opaque_t) ALLOC(am_nfs_handle_t);
771    mf->mf_prfree = (void (*)(opaque_t)) free;
772    memmove(mf->mf_private, (voidp) &fhs, sizeof(fhs));
773  }
774  return error;
775}
776
777
778int
779mount_nfs_fh(am_nfs_handle_t *fhp, char *mntdir, char *fs_name, mntfs *mf)
780{
781  MTYPE_TYPE type;
782  char *colon;
783  char *xopts=NULL, transp_timeo_opts[40], transp_retrans_opts[40];
784  char host[MAXHOSTNAMELEN + MAXPATHLEN + 2];
785  fserver *fs = mf->mf_server;
786  u_long nfs_version = fs->fs_version;
787  char *nfs_proto = fs->fs_proto; /* "tcp" or "udp" */
788  int on_autofs = mf->mf_flags & MFF_ON_AUTOFS;
789  int error;
790  int genflags;
791  int retry;
792  int proto = AMU_TYPE_NONE;
793  mntent_t mnt;
794  void *argsp;
795  nfs_args_t nfs_args;
796#ifdef HAVE_FS_NFS4
797  nfs4_args_t nfs4_args;
798#endif /* HAVE_FS_NFS4 */
799
800  /*
801   * Extract HOST name to give to kernel.
802   * Some systems like osf1/aix3/bsd44 variants may need old code
803   * for NFS_ARGS_NEEDS_PATH.
804   */
805  if (!(colon = strchr(fs_name, ':')))
806    return ENOENT;
807#ifdef MOUNT_TABLE_ON_FILE
808  *colon = '\0';
809#endif /* MOUNT_TABLE_ON_FILE */
810  xstrlcpy(host, fs_name, sizeof(host));
811#ifdef MOUNT_TABLE_ON_FILE
812  *colon = ':';
813#endif /* MOUNT_TABLE_ON_FILE */
814#ifdef MAXHOSTNAMELEN
815  /* most kernels have a name length restriction */
816  if (strlen(host) >= MAXHOSTNAMELEN)
817    xstrlcpy(host + MAXHOSTNAMELEN - 3, "..",
818	     sizeof(host) - MAXHOSTNAMELEN + 3);
819#endif /* MAXHOSTNAMELEN */
820
821  /*
822   * Create option=VAL for udp/tcp specific timeouts and retrans values, but
823   * only if these options were specified.
824   */
825
826  transp_timeo_opts[0] = transp_retrans_opts[0] = '\0';	/* initialize */
827  if (STREQ(nfs_proto, "udp"))
828    proto = AMU_TYPE_UDP;
829  else if (STREQ(nfs_proto, "tcp"))
830    proto = AMU_TYPE_TCP;
831  if (proto != AMU_TYPE_NONE) {
832    if (gopt.amfs_auto_timeo[proto] > 0)
833      xsnprintf(transp_timeo_opts, sizeof(transp_timeo_opts), "%s=%d,",
834		MNTTAB_OPT_TIMEO, gopt.amfs_auto_timeo[proto]);
835    if (gopt.amfs_auto_retrans[proto] > 0)
836      xsnprintf(transp_retrans_opts, sizeof(transp_retrans_opts), "%s=%d,",
837		MNTTAB_OPT_RETRANS, gopt.amfs_auto_retrans[proto]);
838  }
839
840  if (mf->mf_remopts && *mf->mf_remopts &&
841      !islocalnet(fs->fs_ip->sin_addr.s_addr)) {
842    plog(XLOG_INFO, "Using remopts=\"%s\"", mf->mf_remopts);
843    /* use transp_opts first, so map-specific opts will override */
844    xopts = str3cat(xopts, transp_timeo_opts, transp_retrans_opts, mf->mf_remopts);
845  } else {
846    /* use transp_opts first, so map-specific opts will override */
847    xopts = str3cat(xopts, transp_timeo_opts, transp_retrans_opts, mf->mf_mopts);
848  }
849
850  memset((voidp) &mnt, 0, sizeof(mnt));
851  mnt.mnt_dir = mntdir;
852  mnt.mnt_fsname = fs_name;
853  mnt.mnt_opts = xopts;
854
855  /*
856   * Set mount types accordingly
857   */
858#ifdef HAVE_FS_NFS3
859  if (nfs_version == NFS_VERSION3) {
860    type = MOUNT_TYPE_NFS3;
861    /*
862     * Systems that include the mount table "vers" option generally do not
863     * set the mnttab entry to "nfs3", but to "nfs" and then they set
864     * "vers=3".  Setting it to "nfs3" works, but it may break some things
865     * like "df -t nfs" and the "quota" program (esp. on Solaris and Irix).
866     * So on those systems, set it to "nfs".
867     * Note: MNTTAB_OPT_VERS is always set for NFS3 (see am_compat.h).
868     */
869    argsp = &nfs_args;
870# if defined(MNTTAB_OPT_VERS) && defined(MOUNT_TABLE_ON_FILE)
871    mnt.mnt_type = MNTTAB_TYPE_NFS;
872# else /* defined(MNTTAB_OPT_VERS) && defined(MOUNT_TABLE_ON_FILE) */
873    mnt.mnt_type = MNTTAB_TYPE_NFS3;
874# endif /* defined(MNTTAB_OPT_VERS) && defined(MOUNT_TABLE_ON_FILE) */
875# ifdef HAVE_FS_NFS4
876  } else if (nfs_version == NFS_VERSION4) {
877    argsp = &nfs4_args;
878    type = MOUNT_TYPE_NFS4;
879    mnt.mnt_type = MNTTAB_TYPE_NFS4;
880# endif /* HAVE_FS_NFS4 */
881  } else
882#endif /* HAVE_FS_NFS3 */
883  {
884    argsp = &nfs_args;
885    type = MOUNT_TYPE_NFS;
886    mnt.mnt_type = MNTTAB_TYPE_NFS;
887  }
888  plog(XLOG_INFO, "mount_nfs_fh: NFS version %d", (int) nfs_version);
889  plog(XLOG_INFO, "mount_nfs_fh: using NFS transport %s", nfs_proto);
890
891  retry = hasmntval(&mnt, MNTTAB_OPT_RETRY);
892  if (retry <= 0)
893    retry = 1;			/* XXX */
894
895  genflags = compute_mount_flags(&mnt);
896#ifdef HAVE_FS_AUTOFS
897  if (on_autofs)
898    genflags |= autofs_compute_mount_flags(&mnt);
899#endif /* HAVE_FS_AUTOFS */
900
901   /* setup the many fields and flags within nfs_args */
902   compute_nfs_args(argsp,
903		    &mnt,
904		    genflags,
905		    NULL,	/* struct netconfig *nfsncp */
906		    fs->fs_ip,
907		    nfs_version,
908		    nfs_proto,
909		    fhp,
910		    host,
911		    fs_name);
912
913  /* finally call the mounting function */
914  if (amuDebug(D_TRACE)) {
915    print_nfs_args(argsp, nfs_version);
916    plog(XLOG_DEBUG, "Generic mount flags 0x%x used for NFS mount", genflags);
917  }
918  error = mount_fs(&mnt, genflags, argsp, retry, type,
919		   nfs_version, nfs_proto, mnttab_file_name, on_autofs);
920  XFREE(mnt.mnt_opts);
921  discard_nfs_args(argsp, nfs_version);
922
923#ifdef HAVE_FS_NFS4
924# ifndef NO_FALLBACK
925  /*
926   * If we are using a v4 file handle, we try a v3 if we get back:
927   * 	ENOENT: NFS v4 has a different export list than v3
928   * 	EPERM: Kernels <= 2.6.18 return that, instead of ENOENT
929   */
930  if ((error == ENOENT || error == EPERM) && nfs_version == NFS_VERSION4) {
931    plog(XLOG_DEBUG, "Could not find NFS 4 mount, trying again with NFS 3");
932    fs->fs_version = NFS_VERSION3;
933    error = mount_nfs_fh(fhp, mntdir, fs_name, mf);
934    if (error)
935      fs->fs_version = NFS_VERSION4;
936  }
937# endif /* NO_FALLBACK */
938#endif /* HAVE_FS_NFS4 */
939
940  return error;
941}
942
943
944static int
945nfs_mount(am_node *am, mntfs *mf)
946{
947  int error = 0;
948  mntent_t mnt;
949
950  if (!mf->mf_private && mf->mf_server->fs_version != 4) {
951    plog(XLOG_ERROR, "Missing filehandle for %s", mf->mf_info);
952    return EINVAL;
953  }
954
955  if (mf->mf_mopts == NULL) {
956    plog(XLOG_ERROR, "Missing mount options for %s", mf->mf_info);
957    return EINVAL;
958  }
959
960  mnt.mnt_opts = mf->mf_mopts;
961  if (amu_hasmntopt(&mnt, "softlookup") ||
962      (amu_hasmntopt(&mnt, "soft") && !amu_hasmntopt(&mnt, "nosoftlookup")))
963    am->am_flags |= AMF_SOFTLOOKUP;
964
965  error = mount_nfs_fh((am_nfs_handle_t *) mf->mf_private,
966		       mf->mf_mount,
967		       mf->mf_info,
968		       mf);
969
970  if (error) {
971    errno = error;
972    dlog("mount_nfs: %m");
973  }
974
975  return error;
976}
977
978
979static int
980nfs_umount(am_node *am, mntfs *mf)
981{
982  int unmount_flags, new_unmount_flags, error;
983
984  dlog("attempting nfs umount");
985  unmount_flags = (mf->mf_flags & MFF_ON_AUTOFS) ? AMU_UMOUNT_AUTOFS : 0;
986  error = UMOUNT_FS(mf->mf_mount, mnttab_file_name, unmount_flags);
987
988#if defined(HAVE_UMOUNT2) && (defined(MNT2_GEN_OPT_FORCE) || defined(MNT2_GEN_OPT_DETACH))
989  /*
990   * If the attempt to unmount failed with EBUSY, and this fserver was
991   * marked for forced unmounts, then use forced/lazy unmounts.
992   */
993  if (error == EBUSY &&
994      gopt.flags & CFM_FORCED_UNMOUNTS &&
995      mf->mf_server->fs_flags & FSF_FORCE_UNMOUNT) {
996    plog(XLOG_INFO, "EZK: nfs_umount: trying forced/lazy unmounts");
997    /*
998     * XXX: turning off the FSF_FORCE_UNMOUNT may not be perfectly
999     * incorrect.  Multiple nodes may need to be timed out and restarted for
1000     * a single hung fserver.
1001     */
1002    mf->mf_server->fs_flags &= ~FSF_FORCE_UNMOUNT;
1003    new_unmount_flags = unmount_flags | AMU_UMOUNT_FORCE | AMU_UMOUNT_DETACH;
1004    error = UMOUNT_FS(mf->mf_mount, mnttab_file_name, new_unmount_flags);
1005  }
1006#endif /* HAVE_UMOUNT2 && (MNT2_GEN_OPT_FORCE || MNT2_GEN_OPT_DETACH) */
1007
1008  /*
1009   * Here is some code to unmount 'restarted' file systems.
1010   * The restarted file systems are marked as 'nfs', not
1011   * 'host', so we only have the map information for the
1012   * the top-level mount.  The unmount will fail (EBUSY)
1013   * if there are anything else from the NFS server mounted
1014   * below the mount-point.  This code checks to see if there
1015   * is anything mounted with the same prefix as the
1016   * file system to be unmounted ("/a/b/c" when unmounting "/a/b").
1017   * If there is, and it is a 'restarted' file system, we unmount
1018   * it.
1019   * Added by Mike Mitchell, mcm@unx.sas.com, 09/08/93
1020   */
1021  if (error == EBUSY) {
1022    mntfs *new_mf;
1023    int len = strlen(mf->mf_mount);
1024    int didsome = 0;
1025
1026    ITER(new_mf, mntfs, &mfhead) {
1027      if (new_mf->mf_ops != mf->mf_ops ||
1028	  new_mf->mf_refc > 1 ||
1029	  mf == new_mf ||
1030	  ((new_mf->mf_flags & (MFF_MOUNTED | MFF_UNMOUNTING | MFF_RESTART)) == (MFF_MOUNTED | MFF_RESTART)))
1031	continue;
1032
1033      if (NSTREQ(mf->mf_mount, new_mf->mf_mount, len) &&
1034	  new_mf->mf_mount[len] == '/') {
1035	new_unmount_flags =
1036	  (new_mf->mf_flags & MFF_ON_AUTOFS) ? AMU_UMOUNT_AUTOFS : 0;
1037	UMOUNT_FS(new_mf->mf_mount, mnttab_file_name, new_unmount_flags);
1038	didsome = 1;
1039      }
1040    }
1041    if (didsome)
1042      error = UMOUNT_FS(mf->mf_mount, mnttab_file_name, unmount_flags);
1043  }
1044  if (error)
1045    return error;
1046
1047  return 0;
1048}
1049
1050
1051static void
1052nfs_umounted(mntfs *mf)
1053{
1054  fserver *fs;
1055  char *colon, *path;
1056
1057  if (mf->mf_error || mf->mf_refc > 1)
1058    return;
1059
1060  /*
1061   * No need to inform mountd when WebNFS is in use.
1062   */
1063  if (mf->mf_flags & MFF_WEBNFS)
1064    return;
1065
1066  /*
1067   * Call the mount daemon on the server to announce that we are not using
1068   * the fs any more.
1069   *
1070   * XXX: This is *wrong*.  The mountd should be called when the fhandle is
1071   * flushed from the cache, and a reference held to the cached entry while
1072   * the fs is mounted...
1073   */
1074  fs = mf->mf_server;
1075  colon = path = strchr(mf->mf_info, ':');
1076  if (fs && colon) {
1077    fh_cache f;
1078
1079    dlog("calling mountd for %s", mf->mf_info);
1080    *path++ = '\0';
1081    f.fh_path = path;
1082    f.fh_sin = *fs->fs_ip;
1083    f.fh_sin.sin_port = (u_short) 0;
1084    f.fh_nfs_version = SET_FH_VERSION(fs);
1085    f.fh_fs = fs;
1086    f.fh_id = 0;
1087    f.fh_error = 0;
1088    prime_nfs_fhandle_cache(colon + 1, mf->mf_server, (am_nfs_handle_t *) NULL, mf);
1089    call_mountd(&f, MOUNTPROC_UMNT, (fwd_fun *) NULL, (wchan_t) NULL);
1090    *colon = ':';
1091  }
1092}
1093