xref: /dragonfly/sys/vfs/nfs/nfs_socket.c (revision b272101acc636ac635f83d03265ef6a44a3ba51a)
1 /*
2  * Copyright (c) 1989, 1991, 1993, 1995
3  *        The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Rick Macklem at The University of Guelph.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its 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 REGENTS 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 REGENTS 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  *        @(#)nfs_socket.c    8.5 (Berkeley) 3/30/95
33  * $FreeBSD: src/sys/nfs/nfs_socket.c,v 1.60.2.6 2003/03/26 01:44:46 alfred Exp $
34  */
35 
36 /*
37  * Socket operations for use by nfs
38  */
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/proc.h>
43 #include <sys/malloc.h>
44 #include <sys/mount.h>
45 #include <sys/kernel.h>
46 #include <sys/mbuf.h>
47 #include <sys/vnode.h>
48 #include <sys/fcntl.h>
49 #include <sys/protosw.h>
50 #include <sys/resourcevar.h>
51 #include <sys/socket.h>
52 #include <sys/socketvar.h>
53 #include <sys/socketops.h>
54 #include <sys/syslog.h>
55 #include <sys/thread.h>
56 #include <sys/tprintf.h>
57 #include <sys/sysctl.h>
58 #include <sys/signalvar.h>
59 
60 #include <sys/signal2.h>
61 #include <sys/mutex2.h>
62 #include <sys/socketvar2.h>
63 
64 #include <netinet/in.h>
65 #include <netinet/tcp.h>
66 #include <sys/thread2.h>
67 
68 #include "rpcv2.h"
69 #include "nfsproto.h"
70 #include "nfs.h"
71 #include "xdr_subs.h"
72 #include "nfsm_subs.h"
73 #include "nfsmount.h"
74 #include "nfsnode.h"
75 #include "nfsrtt.h"
76 
77 #define   TRUE      1
78 #define   FALSE     0
79 
80 /*
81  * RTT calculations are scaled by 256 (8 bits).  A proper fractional
82  * RTT will still be calculated even with a slow NFS timer.
83  */
84 #define   NFS_SRTT(r)         (r)->r_nmp->nm_srtt[proct[(r)->r_procnum]]
85 #define   NFS_SDRTT(r)        (r)->r_nmp->nm_sdrtt[proct[(r)->r_procnum]]
86 #define NFS_RTT_SCALE_BITS    8         /* bits */
87 #define NFS_RTT_SCALE                   256       /* value */
88 
89 /*
90  * Defines which timer to use for the procnum.
91  * 0 - default
92  * 1 - getattr
93  * 2 - lookup
94  * 3 - read
95  * 4 - write
96  */
97 static int proct[NFS_NPROCS] = {
98           0, 1, 0, 2, 1, 3, 3, 4, 0, 0, /* 00-09  */
99           0, 0, 0, 0, 0, 0, 3, 3, 0, 0, /* 10-19  */
100           0, 5, 0, 0, 0, 0,             /* 20-29  */
101 };
102 
103 static int multt[NFS_NPROCS] = {
104           1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 00-09  */
105           1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 10-19  */
106           1, 2, 1, 1, 1, 1,             /* 20-29  */
107 };
108 
109 static int nfs_backoff[8] = { 2, 3, 5, 8, 13, 21, 34, 55 };
110 static int nfs_realign_test;
111 static int nfs_realign_count;
112 static int nfs_showrtt;
113 static int nfs_showrexmit;
114 int nfs_maxasyncbio = NFS_MAXASYNCBIO;
115 
116 SYSCTL_DECL(_vfs_nfs);
117 
118 SYSCTL_INT(_vfs_nfs, OID_AUTO, realign_test, CTLFLAG_RW, &nfs_realign_test, 0,
119     "Number of times mbufs have been tested for bad alignment");
120 SYSCTL_INT(_vfs_nfs, OID_AUTO, realign_count, CTLFLAG_RW, &nfs_realign_count, 0,
121     "Number of realignments for badly aligned mbuf data");
122 SYSCTL_INT(_vfs_nfs, OID_AUTO, showrtt, CTLFLAG_RW, &nfs_showrtt, 0,
123     "Show round trip time output");
124 SYSCTL_INT(_vfs_nfs, OID_AUTO, showrexmit, CTLFLAG_RW, &nfs_showrexmit, 0,
125     "Show retransmits info");
126 SYSCTL_INT(_vfs_nfs, OID_AUTO, maxasyncbio, CTLFLAG_RW, &nfs_maxasyncbio, 0,
127     "Max number of asynchronous bio's");
128 
129 static int nfs_request_setup(nfsm_info_t info);
130 static int nfs_request_auth(struct nfsreq *rep);
131 static int nfs_request_try(struct nfsreq *rep);
132 static int nfs_request_waitreply(struct nfsreq *rep);
133 static int nfs_request_processreply(nfsm_info_t info, int);
134 
135 int nfsrtton = 0;
136 struct nfsrtt nfsrtt;
137 struct callout      nfs_timer_handle;
138 
139 static int          nfs_msg (struct thread *,char *,char *);
140 static int          nfs_rcvlock (struct nfsmount *nmp, struct nfsreq *myreq);
141 static void         nfs_rcvunlock (struct nfsmount *nmp);
142 static void         nfs_realign (struct mbuf **pm, int hsiz);
143 static int          nfs_receive (struct nfsmount *nmp, struct nfsreq *rep,
144                                         struct sockaddr **aname, struct mbuf **mp);
145 static void         nfs_softterm (struct nfsreq *rep, int islocked);
146 static void         nfs_hardterm (struct nfsreq *rep, int islocked);
147 static int          nfs_reconnect (struct nfsmount *nmp, struct nfsreq *rep);
148 #ifndef NFS_NOSERVER
149 static int          nfsrv_getstream (struct nfssvc_sock *, int, int *);
150 static void         nfs_timer_req(struct nfsreq *req);
151 static void         nfs_checkpkt(struct mbuf *m, int len);
152 
153 int (*nfsrv3_procs[NFS_NPROCS]) (struct nfsrv_descript *nd,
154                                             struct nfssvc_sock *slp,
155                                             struct thread *td,
156                                             struct mbuf **mreqp) = {
157           nfsrv_null,
158           nfsrv_getattr,
159           nfsrv_setattr,
160           nfsrv_lookup,
161           nfsrv3_access,
162           nfsrv_readlink,
163           nfsrv_read,
164           nfsrv_write,
165           nfsrv_create,
166           nfsrv_mkdir,
167           nfsrv_symlink,
168           nfsrv_mknod,
169           nfsrv_remove,
170           nfsrv_rmdir,
171           nfsrv_rename,
172           nfsrv_link,
173           nfsrv_readdir,
174           nfsrv_readdirplus,
175           nfsrv_statfs,
176           nfsrv_fsinfo,
177           nfsrv_pathconf,
178           nfsrv_commit,
179           nfsrv_noop,
180           nfsrv_noop,
181           nfsrv_noop,
182           nfsrv_noop
183 };
184 #endif /* NFS_NOSERVER */
185 
186 /*
187  * Initialize sockets and congestion for a new NFS connection.
188  * We do not free the sockaddr if error.
189  */
190 int
nfs_connect(struct nfsmount * nmp,struct nfsreq * rep)191 nfs_connect(struct nfsmount *nmp, struct nfsreq *rep)
192 {
193           struct socket *so;
194           int error;
195           struct sockaddr *saddr;
196           struct sockaddr_in *sin;
197           struct thread *td = &thread0; /* only used for socreate and sobind */
198 
199           nmp->nm_so = so = NULL;
200           if (nmp->nm_flag & NFSMNT_FORCE)
201                     return (EINVAL);
202           saddr = nmp->nm_nam;
203           error = socreate(saddr->sa_family, &so, nmp->nm_sotype,
204                     nmp->nm_soproto, td);
205           if (error)
206                     goto bad;
207           nmp->nm_soflags = so->so_proto->pr_flags;
208 
209           /*
210            * Some servers require that the client port be a reserved port number.
211            */
212           if (saddr->sa_family == AF_INET && (nmp->nm_flag & NFSMNT_RESVPORT)) {
213                     struct sockopt sopt;
214                     int ip;
215                     struct sockaddr_in ssin;
216 
217                     bzero(&sopt, sizeof sopt);
218                     ip = IP_PORTRANGE_LOW;
219                     sopt.sopt_level = IPPROTO_IP;
220                     sopt.sopt_name = IP_PORTRANGE;
221                     sopt.sopt_val = (void *)&ip;
222                     sopt.sopt_valsize = sizeof(ip);
223                     sopt.sopt_td = NULL;
224                     error = sosetopt(so, &sopt);
225                     if (error)
226                               goto bad;
227                     bzero(&ssin, sizeof ssin);
228                     sin = &ssin;
229                     sin->sin_len = sizeof (struct sockaddr_in);
230                     sin->sin_family = AF_INET;
231                     sin->sin_addr.s_addr = INADDR_ANY;
232                     sin->sin_port = htons(0);
233                     error = sobind(so, (struct sockaddr *)sin, td);
234                     if (error)
235                               goto bad;
236                     bzero(&sopt, sizeof sopt);
237                     ip = IP_PORTRANGE_DEFAULT;
238                     sopt.sopt_level = IPPROTO_IP;
239                     sopt.sopt_name = IP_PORTRANGE;
240                     sopt.sopt_val = (void *)&ip;
241                     sopt.sopt_valsize = sizeof(ip);
242                     sopt.sopt_td = NULL;
243                     error = sosetopt(so, &sopt);
244                     if (error)
245                               goto bad;
246           }
247 
248           /*
249            * Protocols that do not require connections may be optionally left
250            * unconnected for servers that reply from a port other than NFS_PORT.
251            */
252           if (nmp->nm_flag & NFSMNT_NOCONN) {
253                     if (nmp->nm_soflags & PR_CONNREQUIRED) {
254                               error = ENOTCONN;
255                               goto bad;
256                     }
257           } else {
258                     error = soconnect(so, nmp->nm_nam, td, TRUE);
259                     if (error)
260                               goto bad;
261 
262                     /*
263                      * Wait for the connection to complete. Cribbed from the
264                      * connect system call but with the wait timing out so
265                      * that interruptible mounts don't hang here for a long time.
266                      */
267                     crit_enter();
268                     while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
269                               (void) tsleep((caddr_t)&so->so_timeo, 0,
270                                         "nfscon", 2 * hz);
271                               if ((so->so_state & SS_ISCONNECTING) &&
272                                   so->so_error == 0 && rep &&
273                                   (error = nfs_sigintr(nmp, rep, rep->r_td)) != 0){
274                                         soclrstate(so, SS_ISCONNECTING);
275                                         crit_exit();
276                                         goto bad;
277                               }
278                     }
279                     if (so->so_error) {
280                               error = so->so_error;
281                               so->so_error = 0;
282                               crit_exit();
283                               goto bad;
284                     }
285                     crit_exit();
286           }
287           so->so_rcv.ssb_timeo = (5 * hz);
288           so->so_snd.ssb_timeo = (5 * hz);
289 
290           /*
291            * Get buffer reservation size from sysctl, but impose reasonable
292            * limits.
293            */
294           if (nmp->nm_sotype == SOCK_STREAM) {
295                     if (so->so_proto->pr_flags & PR_CONNREQUIRED) {
296                               struct sockopt sopt;
297                               int val;
298 
299                               bzero(&sopt, sizeof sopt);
300                               sopt.sopt_level = SOL_SOCKET;
301                               sopt.sopt_name = SO_KEEPALIVE;
302                               sopt.sopt_val = &val;
303                               sopt.sopt_valsize = sizeof val;
304                               val = 1;
305                               sosetopt(so, &sopt);
306                     }
307                     if (so->so_proto->pr_protocol == IPPROTO_TCP) {
308                               struct sockopt sopt;
309                               int val;
310 
311                               bzero(&sopt, sizeof sopt);
312                               sopt.sopt_level = IPPROTO_TCP;
313                               sopt.sopt_name = TCP_NODELAY;
314                               sopt.sopt_val = &val;
315                               sopt.sopt_valsize = sizeof val;
316                               val = 1;
317                               sosetopt(so, &sopt);
318 
319                               bzero(&sopt, sizeof sopt);
320                               sopt.sopt_level = IPPROTO_TCP;
321                               sopt.sopt_name = TCP_FASTKEEP;
322                               sopt.sopt_val = &val;
323                               sopt.sopt_valsize = sizeof val;
324                               val = 1;
325                               sosetopt(so, &sopt);
326                     }
327           }
328           error = soreserve(so, nfs_soreserve, nfs_soreserve, NULL);
329           if (error)
330                     goto bad;
331           atomic_set_int(&so->so_rcv.ssb_flags, SSB_NOINTR);
332           atomic_set_int(&so->so_snd.ssb_flags, SSB_NOINTR);
333 
334           /*
335            * Clear AUTOSIZE, otherwise the socket buffer could be reduced
336            * to the point where rpc's cannot be queued using the mbuf
337            * interface.
338            */
339           atomic_clear_int(&so->so_rcv.ssb_flags, SSB_AUTOSIZE);
340           atomic_clear_int(&so->so_snd.ssb_flags, SSB_AUTOSIZE);
341 
342           /* Initialize other non-zero congestion variables */
343           nmp->nm_srtt[0] = nmp->nm_srtt[1] = nmp->nm_srtt[2] =
344                     nmp->nm_srtt[3] = (NFS_TIMEO << NFS_RTT_SCALE_BITS);
345           nmp->nm_sdrtt[0] = nmp->nm_sdrtt[1] = nmp->nm_sdrtt[2] =
346                     nmp->nm_sdrtt[3] = 0;
347           nmp->nm_maxasync_scaled = NFS_MINASYNC_SCALED;
348           nmp->nm_timeouts = 0;
349 
350           /*
351            * Assign nm_so last.  The moment nm_so is assigned the nfs_timer()
352            * can mess with the socket.
353            */
354           nmp->nm_so = so;
355           return (0);
356 
357 bad:
358           if (so) {
359                     soshutdown(so, SHUT_RDWR);
360                     soclose(so, FNONBLOCK);
361           }
362           return (error);
363 }
364 
365 /*
366  * Reconnect routine:
367  * Called when a connection is broken on a reliable protocol.
368  * - clean up the old socket
369  * - nfs_connect() again
370  * - set R_NEEDSXMIT for all outstanding requests on mount point
371  * If this fails the mount point is DEAD!
372  * nb: Must be called with the nfs_sndlock() set on the mount point.
373  */
374 static int
nfs_reconnect(struct nfsmount * nmp,struct nfsreq * rep)375 nfs_reconnect(struct nfsmount *nmp, struct nfsreq *rep)
376 {
377           struct nfsreq *req;
378           int error;
379 
380           nfs_disconnect(nmp);
381           if (nmp->nm_rxstate >= NFSSVC_STOPPING)
382                     return (EINTR);
383           while ((error = nfs_connect(nmp, rep)) != 0) {
384                     if (error == EINTR || error == ERESTART)
385                               return (EINTR);
386                     if (error == EINVAL)
387                               return (error);
388                     if (nmp->nm_rxstate >= NFSSVC_STOPPING)
389                               return (EINTR);
390                     (void) tsleep((caddr_t)&lbolt, 0, "nfscon", 0);
391           }
392 
393           /*
394            * Loop through outstanding request list and fix up all requests
395            * on old socket.
396            */
397           crit_enter();
398           TAILQ_FOREACH(req, &nmp->nm_reqq, r_chain) {
399                     KKASSERT(req->r_nmp == nmp);
400                     req->r_flags |= R_NEEDSXMIT;
401           }
402           crit_exit();
403           return (0);
404 }
405 
406 /*
407  * NFS disconnect. Clean up and unlink.
408  */
409 void
nfs_disconnect(struct nfsmount * nmp)410 nfs_disconnect(struct nfsmount *nmp)
411 {
412           struct socket *so;
413 
414           if (nmp->nm_so) {
415                     so = nmp->nm_so;
416                     nmp->nm_so = NULL;
417                     soshutdown(so, SHUT_RDWR);
418                     soclose(so, FNONBLOCK);
419           }
420 }
421 
422 void
nfs_safedisconnect(struct nfsmount * nmp)423 nfs_safedisconnect(struct nfsmount *nmp)
424 {
425           int error;
426 
427           error = nfs_rcvlock(nmp, NULL);
428           nfs_disconnect(nmp);
429           if (error == 0)
430                     nfs_rcvunlock(nmp);
431 }
432 
433 /*
434  * This is the nfs send routine. For connection based socket types, it
435  * must be called with an nfs_sndlock() on the socket.
436  * "rep == NULL" indicates that it has been called from a server.
437  * For the client side:
438  * - return EINTR if the RPC is terminated, 0 otherwise
439  * - set R_NEEDSXMIT if the send fails for any reason
440  * - do any cleanup required by recoverable socket errors (?)
441  * For the server side:
442  * - return EINTR or ERESTART if interrupted by a signal
443  * - return EPIPE if a connection is lost for connection based sockets (TCP...)
444  * - do any cleanup required by recoverable socket errors (?)
445  */
446 int
nfs_send(struct socket * so,struct sockaddr * nam,struct mbuf * top,struct nfsreq * rep)447 nfs_send(struct socket *so, struct sockaddr *nam, struct mbuf *top,
448            struct nfsreq *rep)
449 {
450           struct sockaddr *sendnam;
451           int error, soflags, flags;
452 
453           if (rep) {
454                     if (rep->r_flags & R_SOFTTERM) {
455                               m_freem(top);
456                               return (EINTR);
457                     }
458                     if ((so = rep->r_nmp->nm_so) == NULL) {
459                               rep->r_flags |= R_NEEDSXMIT;
460                               m_freem(top);
461                               return (0);
462                     }
463                     rep->r_flags &= ~R_NEEDSXMIT;
464                     soflags = rep->r_nmp->nm_soflags;
465           } else {
466                     soflags = so->so_proto->pr_flags;
467           }
468           if ((soflags & PR_CONNREQUIRED) || (so->so_state & SS_ISCONNECTED))
469                     sendnam = NULL;
470           else
471                     sendnam = nam;
472           if (so->so_type == SOCK_SEQPACKET)
473                     flags = MSG_EOR;
474           else
475                     flags = 0;
476 
477           /*
478            * calls pru_sosend -> sosend -> so_pru_send -> netrpc
479            */
480           error = so_pru_sosend(so, sendnam, NULL, top, NULL, flags,
481                                     curthread /*XXX*/);
482 
483           /*
484            * ENOBUFS for dgram sockets is transient and non fatal.
485            * No need to log, and no need to break a soft mount.
486            */
487           if (error == ENOBUFS && so->so_type == SOCK_DGRAM) {
488                     error = 0;
489                     /*
490                      * do backoff retransmit on client
491                      */
492                     if (rep) {
493                               if ((rep->r_nmp->nm_state & NFSSTA_SENDSPACE) == 0) {
494                                         rep->r_nmp->nm_state |= NFSSTA_SENDSPACE;
495                                         kprintf("Warning: NFS: Insufficient sendspace "
496                                                   "(%lu),\n"
497                                                   "\t You must increase vfs.nfs.soreserve"
498                                                   "or decrease vfs.nfs.maxasyncbio\n",
499                                                   so->so_snd.ssb_hiwat);
500                               }
501                               rep->r_flags |= R_NEEDSXMIT;
502                     }
503           }
504 
505           if (error) {
506                     if (rep) {
507                               log(LOG_INFO, "nfs send error %d for server %s\n",error,
508                                   rep->r_nmp->nm_mountp->mnt_stat.f_mntfromname);
509                               /*
510                                * Deal with errors for the client side.
511                                */
512                               if (rep->r_flags & R_SOFTTERM)
513                                         error = EINTR;
514                               else
515                                         rep->r_flags |= R_NEEDSXMIT;
516                     } else {
517                               log(LOG_INFO, "nfsd send error %d\n", error);
518                     }
519 
520                     /*
521                      * Handle any recoverable (soft) socket errors here. (?)
522                      */
523                     if (error != EINTR && error != ERESTART &&
524                               error != EWOULDBLOCK && error != EPIPE)
525                               error = 0;
526           }
527           return (error);
528 }
529 
530 /*
531  * Receive a Sun RPC Request/Reply. For SOCK_DGRAM, the work is all
532  * done by soreceive(), but for SOCK_STREAM we must deal with the Record
533  * Mark and consolidate the data into a new mbuf list.
534  * nb: Sometimes TCP passes the data up to soreceive() in long lists of
535  *     small mbufs.
536  * For SOCK_STREAM we must be very careful to read an entire record once
537  * we have read any of it, even if the system call has been interrupted.
538  */
539 static int
nfs_receive(struct nfsmount * nmp,struct nfsreq * rep,struct sockaddr ** aname,struct mbuf ** mp)540 nfs_receive(struct nfsmount *nmp, struct nfsreq *rep,
541               struct sockaddr **aname, struct mbuf **mp)
542 {
543           struct socket *so;
544           struct sockbuf sio;
545           struct uio auio;
546           struct iovec aio;
547           struct mbuf *m;
548           struct mbuf *control;
549           u_int32_t len;
550           struct sockaddr **getnam;
551           int error, sotype, rcvflg;
552           struct thread *td = curthread;          /* XXX */
553 
554           /*
555            * Set up arguments for soreceive()
556            */
557           *mp = NULL;
558           *aname = NULL;
559           sotype = nmp->nm_sotype;
560 
561           /*
562            * For reliable protocols, lock against other senders/receivers
563            * in case a reconnect is necessary.
564            * For SOCK_STREAM, first get the Record Mark to find out how much
565            * more there is to get.
566            * We must lock the socket against other receivers
567            * until we have an entire rpc request/reply.
568            */
569           if (sotype != SOCK_DGRAM) {
570                     error = nfs_sndlock(nmp, rep);
571                     if (error)
572                               return (error);
573 tryagain:
574                     /*
575                      * Check for fatal errors and resending request.
576                      */
577                     /*
578                      * Ugh: If a reconnect attempt just happened, nm_so
579                      * would have changed. NULL indicates a failed
580                      * attempt that has essentially shut down this
581                      * mount point.
582                      */
583                     if (rep && (rep->r_mrep || (rep->r_flags & R_SOFTTERM))) {
584                               nfs_sndunlock(nmp);
585                               return (EINTR);
586                     }
587                     so = nmp->nm_so;
588                     if (so == NULL) {
589                               error = nfs_reconnect(nmp, rep);
590                               if (error) {
591                                         nfs_sndunlock(nmp);
592                                         return (error);
593                               }
594                               goto tryagain;
595                     }
596                     while (rep && (rep->r_flags & R_NEEDSXMIT)) {
597                               m = m_copym(rep->r_mreq, 0, M_COPYALL, M_WAITOK);
598                               nfsstats.rpcretries++;
599                               error = nfs_send(so, rep->r_nmp->nm_nam, m, rep);
600                               if (error) {
601                                         if (error == EINTR || error == ERESTART ||
602                                             (error = nfs_reconnect(nmp, rep)) != 0) {
603                                                   nfs_sndunlock(nmp);
604                                                   return (error);
605                                         }
606                                         goto tryagain;
607                               }
608                     }
609                     nfs_sndunlock(nmp);
610                     if (sotype == SOCK_STREAM) {
611                               /*
612                                * Get the length marker from the stream
613                                */
614                               aio.iov_base = (caddr_t)&len;
615                               aio.iov_len = sizeof(u_int32_t);
616                               auio.uio_iov = &aio;
617                               auio.uio_iovcnt = 1;
618                               auio.uio_segflg = UIO_SYSSPACE;
619                               auio.uio_rw = UIO_READ;
620                               auio.uio_offset = 0;
621                               auio.uio_resid = sizeof(u_int32_t);
622                               auio.uio_td = td;
623                               do {
624                                  rcvflg = MSG_WAITALL;
625                                  error = so_pru_soreceive(so, NULL, &auio, NULL,
626                                                                 NULL, &rcvflg);
627                                  if (error == EWOULDBLOCK && rep) {
628                                         if (rep->r_flags & R_SOFTTERM)
629                                                   return (EINTR);
630                                  }
631                               } while (error == EWOULDBLOCK);
632 
633                               if (error == 0 && auio.uio_resid > 0) {
634                                   /*
635                                    * Only log short packets if not EOF
636                                    */
637                                   if (auio.uio_resid != sizeof(u_int32_t)) {
638                                         log(LOG_INFO,
639                                             "short receive (%d/%d) from nfs server %s\n",
640                                             (int)(sizeof(u_int32_t) - auio.uio_resid),
641                                             (int)sizeof(u_int32_t),
642                                             nmp->nm_mountp->mnt_stat.f_mntfromname);
643                                   }
644                                   error = EPIPE;
645                               }
646                               if (error)
647                                         goto errout;
648                               len = ntohl(len) & ~0x80000000;
649                               /*
650                                * This is SERIOUS! We are out of sync with the sender
651                                * and forcing a disconnect/reconnect is all I can do.
652                                */
653                               if (len > NFS_MAXPACKET) {
654                                   log(LOG_ERR, "%s (%d) from nfs server %s\n",
655                                         "impossible packet length",
656                                         len,
657                                         nmp->nm_mountp->mnt_stat.f_mntfromname);
658                                   error = EFBIG;
659                                   goto errout;
660                               }
661 
662                               /*
663                                * Get the rest of the packet as an mbuf chain
664                                */
665                               sbinit(&sio, len);
666                               do {
667                                   rcvflg = MSG_WAITALL;
668                                   error = so_pru_soreceive(so, NULL, NULL, &sio,
669                                                                  NULL, &rcvflg);
670                               } while (error == EWOULDBLOCK || error == EINTR ||
671                                          error == ERESTART);
672                               if (error == 0 && sio.sb_cc != len) {
673                                   if (sio.sb_cc != 0) {
674                                         log(LOG_INFO,
675                                             "short receive (%zu/%d) from nfs server %s\n",
676                                             (size_t)len - auio.uio_resid, len,
677                                             nmp->nm_mountp->mnt_stat.f_mntfromname);
678                                   }
679                                   error = EPIPE;
680                               }
681                               *mp = sio.sb_mb;
682                     } else {
683                               /*
684                                * Non-stream, so get the whole packet by not
685                                * specifying MSG_WAITALL and by specifying a large
686                                * length.
687                                *
688                                * We have no use for control msg., but must grab them
689                                * and then throw them away so we know what is going
690                                * on.
691                                */
692                               sbinit(&sio, 100000000);
693                               do {
694                                   rcvflg = 0;
695                                   error =  so_pru_soreceive(so, NULL, NULL, &sio,
696                                                                   &control, &rcvflg);
697                                   if (control)
698                                         m_freem(control);
699                                   if (error == EWOULDBLOCK && rep) {
700                                         if (rep->r_flags & R_SOFTTERM) {
701                                                   m_freem(sio.sb_mb);
702                                                   return (EINTR);
703                                         }
704                                   }
705                               } while (error == EWOULDBLOCK ||
706                                          (error == 0 && sio.sb_mb == NULL && control));
707                               if ((rcvflg & MSG_EOR) == 0)
708                                         kprintf("Egad!!\n");
709                               if (error == 0 && sio.sb_mb == NULL)
710                                         error = EPIPE;
711                               len = sio.sb_cc;
712                               *mp = sio.sb_mb;
713                     }
714 errout:
715                     if (error && error != EINTR && error != ERESTART) {
716                               m_freem(*mp);
717                               *mp = NULL;
718                               if (error != EPIPE) {
719                                         log(LOG_INFO,
720                                             "receive error %d from nfs server %s\n",
721                                             error,
722                                          nmp->nm_mountp->mnt_stat.f_mntfromname);
723                               }
724                               error = nfs_sndlock(nmp, rep);
725                               if (!error) {
726                                         error = nfs_reconnect(nmp, rep);
727                                         if (!error)
728                                                   goto tryagain;
729                                         else
730                                                   nfs_sndunlock(nmp);
731                               }
732                     }
733           } else {
734                     if ((so = nmp->nm_so) == NULL)
735                               return (EACCES);
736                     if (so->so_state & SS_ISCONNECTED)
737                               getnam = NULL;
738                     else
739                               getnam = aname;
740                     sbinit(&sio, 100000000);
741                     do {
742                               rcvflg = 0;
743                               error =  so_pru_soreceive(so, getnam, NULL, &sio,
744                                                               NULL, &rcvflg);
745                               if (error == EWOULDBLOCK && rep &&
746                                   (rep->r_flags & R_SOFTTERM)) {
747                                         m_freem(sio.sb_mb);
748                                         return (EINTR);
749                               }
750                     } while (error == EWOULDBLOCK);
751 
752                     len = sio.sb_cc;
753                     *mp = sio.sb_mb;
754 
755                     /*
756                      * A shutdown may result in no error and no mbuf.
757                      * Convert to EPIPE.
758                      */
759                     if (*mp == NULL && error == 0)
760                               error = EPIPE;
761           }
762           if (error) {
763                     m_freem(*mp);
764                     *mp = NULL;
765           }
766 
767           /*
768            * Search for any mbufs that are not a multiple of 4 bytes long
769            * or with m_data not longword aligned.
770            * These could cause pointer alignment problems, so copy them to
771            * well aligned mbufs.
772            */
773           nfs_realign(mp, 5 * NFSX_UNSIGNED);
774           return (error);
775 }
776 
777 /*
778  * Implement receipt of reply on a socket.
779  *
780  * We must search through the list of received datagrams matching them
781  * with outstanding requests using the xid, until ours is found.
782  *
783  * If myrep is NULL we process packets on the socket until
784  * interrupted or until nm_reqrxq is non-empty.
785  */
786 /* ARGSUSED */
787 int
nfs_reply(struct nfsmount * nmp,struct nfsreq * myrep)788 nfs_reply(struct nfsmount *nmp, struct nfsreq *myrep)
789 {
790           struct nfsreq *rep;
791           struct sockaddr *nam;
792           u_int32_t rxid;
793           u_int32_t *tl;
794           int error;
795           struct nfsm_info info;
796 
797           /*
798            * Loop around until we get our own reply
799            */
800           for (;;) {
801                     /*
802                      * Lock against other receivers so that I don't get stuck in
803                      * sbwait() after someone else has received my reply for me.
804                      * Also necessary for connection based protocols to avoid
805                      * race conditions during a reconnect.
806                      *
807                      * If nfs_rcvlock() returns EALREADY, that means that
808                      * the reply has already been recieved by another
809                      * process and we can return immediately.  In this
810                      * case, the lock is not taken to avoid races with
811                      * other processes.
812                      */
813                     info.mrep = NULL;
814 
815                     error = nfs_rcvlock(nmp, myrep);
816                     if (error == EALREADY)
817                               return (0);
818                     if (error)
819                               return (error);
820 
821                     /*
822                      * If myrep is NULL we are the receiver helper thread.
823                      * Stop waiting for incoming replies if there are
824                      * messages sitting on reqrxq that we need to process,
825                      * or if a shutdown request is pending.
826                      */
827                     if (myrep == NULL && (TAILQ_FIRST(&nmp->nm_reqrxq) ||
828                         nmp->nm_rxstate > NFSSVC_PENDING)) {
829                               nfs_rcvunlock(nmp);
830                               return(EWOULDBLOCK);
831                     }
832 
833                     /*
834                      * Get the next Rpc reply off the socket
835                      *
836                      * We cannot release the receive lock until we've
837                      * filled in rep->r_mrep, otherwise a waiting
838                      * thread may deadlock in soreceive with no incoming
839                      * packets expected.
840                      */
841                     error = nfs_receive(nmp, myrep, &nam, &info.mrep);
842                     if (error) {
843                               /*
844                                * Ignore routing errors on connectionless protocols??
845                                */
846                               nfs_rcvunlock(nmp);
847                               if (NFSIGNORE_SOERROR(nmp->nm_soflags, error)) {
848                                         if (nmp->nm_so == NULL)
849                                                   return (error);
850                                         nmp->nm_so->so_error = 0;
851                                         continue;
852                               }
853                               return (error);
854                     }
855                     if (nam)
856                               kfree(nam, M_SONAME);
857 
858                     /*
859                      * Get the xid and check that it is an rpc reply
860                      */
861                     info.md = info.mrep;
862                     info.dpos = mtod(info.md, caddr_t);
863                     NULLOUT(tl = nfsm_dissect(&info, 2*NFSX_UNSIGNED));
864                     rxid = *tl++;
865                     if (*tl != rpc_reply) {
866                               nfsstats.rpcinvalid++;
867                               m_freem(info.mrep);
868                               info.mrep = NULL;
869 nfsmout:
870                               nfs_rcvunlock(nmp);
871                               continue;
872                     }
873 
874                     /*
875                      * Loop through the request list to match up the reply
876                      * Iff no match, just drop the datagram.  On match, set
877                      * r_mrep atomically to prevent the timer from messing
878                      * around with the request after we have exited the critical
879                      * section.
880                      */
881                     crit_enter();
882                     TAILQ_FOREACH(rep, &nmp->nm_reqq, r_chain) {
883                               if (rep->r_mrep == NULL && rxid == rep->r_xid)
884                                         break;
885                     }
886 
887                     /*
888                      * Fill in the rest of the reply if we found a match.
889                      *
890                      * Deal with duplicate responses if there was no match.
891                      */
892                     if (rep) {
893                               rep->r_md = info.md;
894                               rep->r_dpos = info.dpos;
895                               if (nfsrtton) {
896                                         struct rttl *rt;
897 
898                                         rt = &nfsrtt.rttl[nfsrtt.pos];
899                                         rt->proc = rep->r_procnum;
900                                         rt->rto = 0;
901                                         rt->sent = 0;
902                                         rt->cwnd = nmp->nm_maxasync_scaled;
903                                         rt->srtt = nmp->nm_srtt[proct[rep->r_procnum] - 1];
904                                         rt->sdrtt = nmp->nm_sdrtt[proct[rep->r_procnum] - 1];
905                                         rt->fsid = nmp->nm_mountp->mnt_stat.f_fsid;
906                                         getmicrotime(&rt->tstamp);
907                                         if (rep->r_flags & R_TIMING)
908                                                   rt->rtt = rep->r_rtt;
909                                         else
910                                                   rt->rtt = 1000000;
911                                         nfsrtt.pos = (nfsrtt.pos + 1) % NFSRTTLOGSIZ;
912                               }
913 
914                               /*
915                                * New congestion control is based only on async
916                                * requests.
917                                */
918                               if (nmp->nm_maxasync_scaled < NFS_MAXASYNC_SCALED)
919                                         ++nmp->nm_maxasync_scaled;
920                               if (rep->r_flags & R_SENT) {
921                                         rep->r_flags &= ~R_SENT;
922                               }
923                               /*
924                                * Update rtt using a gain of 0.125 on the mean
925                                * and a gain of 0.25 on the deviation.
926                                *
927                                * NOTE SRTT/SDRTT are only good if R_TIMING is set.
928                                */
929                               if ((rep->r_flags & R_TIMING) && rep->r_rexmit == 0) {
930                                         /*
931                                          * Since the timer resolution of
932                                          * NFS_HZ is so course, it can often
933                                          * result in r_rtt == 0. Since
934                                          * r_rtt == N means that the actual
935                                          * rtt is between N+dt and N+2-dt ticks,
936                                          * add 1.
937                                          */
938                                         int n;
939                                         int d;
940 
941 #define NFSRSB      NFS_RTT_SCALE_BITS
942                                         n = ((NFS_SRTT(rep) * 7) +
943                                              (rep->r_rtt << NFSRSB)) >> 3;
944                                         d = n - NFS_SRTT(rep);
945                                         NFS_SRTT(rep) = n;
946 
947                                         /*
948                                          * Don't let the jitter calculation decay
949                                          * too quickly, but we want a fast rampup.
950                                          */
951                                         if (d < 0)
952                                                   d = -d;
953                                         d <<= NFSRSB;
954                                         if (d < NFS_SDRTT(rep))
955                                                   n = ((NFS_SDRTT(rep) * 15) + d) >> 4;
956                                         else
957                                                   n = ((NFS_SDRTT(rep) * 3) + d) >> 2;
958                                         NFS_SDRTT(rep) = n;
959 #undef NFSRSB
960                               }
961                               nmp->nm_timeouts = 0;
962                               rep->r_mrep = info.mrep;
963                               nfs_hardterm(rep, 0);
964                     } else {
965                               /*
966                                * Extract vers, prog, nfsver, procnum.  A duplicate
967                                * response means we didn't wait long enough so
968                                * we increase the SRTT to avoid future spurious
969                                * timeouts.
970                                */
971                               u_int procnum = nmp->nm_lastreprocnum;
972                               int n;
973 
974                               if (procnum < NFS_NPROCS && proct[procnum]) {
975                                         if (nfs_showrexmit)
976                                                   kprintf("D");
977                                         n = nmp->nm_srtt[proct[procnum]];
978                                         n += NFS_ASYSCALE * NFS_HZ;
979                                         if (n < NFS_ASYSCALE * NFS_HZ * 10)
980                                                   n = NFS_ASYSCALE * NFS_HZ * 10;
981                                         nmp->nm_srtt[proct[procnum]] = n;
982                               }
983                     }
984                     nfs_rcvunlock(nmp);
985                     crit_exit();
986 
987                     /*
988                      * If not matched to a request, drop it.
989                      * If it's mine, get out.
990                      */
991                     if (rep == NULL) {
992                               nfsstats.rpcunexpected++;
993                               m_freem(info.mrep);
994                               info.mrep = NULL;
995                     } else if (rep == myrep) {
996                               if (rep->r_mrep == NULL)
997                                         panic("nfsreply nil");
998                               return (0);
999                     }
1000           }
1001 }
1002 
1003 /*
1004  * Run the request state machine until the target state is reached
1005  * or a fatal error occurs.  The target state is not run.  Specifying
1006  * a target of NFSM_STATE_DONE runs the state machine until the rpc
1007  * is complete.
1008  *
1009  * EINPROGRESS is returned for all states other then the DONE state,
1010  * indicating that the rpc is still in progress.
1011  */
1012 int
nfs_request(struct nfsm_info * info,nfsm_state_t bstate,nfsm_state_t estate)1013 nfs_request(struct nfsm_info *info, nfsm_state_t bstate, nfsm_state_t estate)
1014 {
1015           struct nfsreq *req;
1016 
1017           while (info->state >= bstate && info->state < estate) {
1018                     switch(info->state) {
1019                     case NFSM_STATE_SETUP:
1020                               /*
1021                                * Setup the nfsreq.  Any error which occurs during
1022                                * this state is fatal.
1023                                */
1024                               info->error = nfs_request_setup(info);
1025                               if (info->error) {
1026                                         info->state = NFSM_STATE_DONE;
1027                                         return (info->error);
1028                               } else {
1029                                         req = info->req;
1030                                         req->r_mrp = &info->mrep;
1031                                         req->r_mdp = &info->md;
1032                                         req->r_dposp = &info->dpos;
1033                                         info->state = NFSM_STATE_AUTH;
1034                               }
1035                               break;
1036                     case NFSM_STATE_AUTH:
1037                               /*
1038                                * Authenticate the nfsreq.  Any error which occurs
1039                                * during this state is fatal.
1040                                */
1041                               info->error = nfs_request_auth(info->req);
1042                               if (info->error) {
1043                                         info->state = NFSM_STATE_DONE;
1044                                         return (info->error);
1045                               } else {
1046                                         info->state = NFSM_STATE_TRY;
1047                               }
1048                               break;
1049                     case NFSM_STATE_TRY:
1050                               /*
1051                                * Transmit or retransmit attempt.  An error in this
1052                                * state is ignored and we always move on to the
1053                                * next state.
1054                                *
1055                                * This can trivially race the receiver if the
1056                                * request is asynchronous.  nfs_request_try()
1057                                * will thus set the state for us and we
1058                                * must also return immediately if we are
1059                                * running an async state machine, because
1060                                * info can become invalid due to races after
1061                                * try() returns.
1062                                */
1063                               if (info->req->r_flags & R_ASYNC) {
1064                                         nfs_request_try(info->req);
1065                                         if (estate == NFSM_STATE_WAITREPLY)
1066                                                   return (EINPROGRESS);
1067                               } else {
1068                                         nfs_request_try(info->req);
1069                                         info->state = NFSM_STATE_WAITREPLY;
1070                               }
1071                               break;
1072                     case NFSM_STATE_WAITREPLY:
1073                               /*
1074                                * Wait for a reply or timeout and move on to the
1075                                * next state.  The error returned by this state
1076                                * is passed to the processing code in the next
1077                                * state.
1078                                */
1079                               info->error = nfs_request_waitreply(info->req);
1080                               info->state = NFSM_STATE_PROCESSREPLY;
1081                               break;
1082                     case NFSM_STATE_PROCESSREPLY:
1083                               /*
1084                                * Process the reply or timeout.  Errors which occur
1085                                * in this state may cause the state machine to
1086                                * go back to an earlier state, and are fatal
1087                                * otherwise.
1088                                */
1089                               info->error = nfs_request_processreply(info,
1090                                                                              info->error);
1091                               switch(info->error) {
1092                               case ENEEDAUTH:
1093                                         info->state = NFSM_STATE_AUTH;
1094                                         break;
1095                               case EAGAIN:
1096                                         info->state = NFSM_STATE_TRY;
1097                                         break;
1098                               default:
1099                                         /*
1100                                          * Operation complete, with or without an
1101                                          * error.  We are done.
1102                                          */
1103                                         info->req = NULL;
1104                                         info->state = NFSM_STATE_DONE;
1105                                         return (info->error);
1106                               }
1107                               break;
1108                     case NFSM_STATE_DONE:
1109                               /*
1110                                * Shouldn't be reached
1111                                */
1112                               return (info->error);
1113                               /* NOT REACHED */
1114                     }
1115           }
1116 
1117           /*
1118            * If we are done return the error code (if any).
1119            * Otherwise return EINPROGRESS.
1120            */
1121           if (info->state == NFSM_STATE_DONE)
1122                     return (info->error);
1123           return (EINPROGRESS);
1124 }
1125 
1126 /*
1127  * nfs_request - goes something like this
1128  *        - fill in request struct
1129  *        - links it into list
1130  *        - calls nfs_send() for first transmit
1131  *        - calls nfs_receive() to get reply
1132  *        - break down rpc header and return with nfs reply pointed to
1133  *          by mrep or error
1134  * nb: always frees up mreq mbuf list
1135  */
1136 static int
nfs_request_setup(nfsm_info_t info)1137 nfs_request_setup(nfsm_info_t info)
1138 {
1139           struct nfsreq *req;
1140           struct nfsmount *nmp;
1141           struct mbuf *m;
1142           int i;
1143 
1144           /*
1145            * Reject requests while attempting a forced unmount.
1146            */
1147           if (info->vp->v_mount->mnt_kern_flag & MNTK_UNMOUNTF) {
1148                     m_freem(info->mreq);
1149                     info->mreq = NULL;
1150                     return (EIO);
1151           }
1152           nmp = VFSTONFS(info->vp->v_mount);
1153           req = kmalloc(sizeof(struct nfsreq), M_NFSREQ, M_WAITOK);
1154           req->r_nmp = nmp;
1155           req->r_vp = info->vp;
1156           req->r_td = info->td;
1157           req->r_procnum = info->procnum;
1158           req->r_mreq = NULL;
1159           req->r_cred = info->cred;
1160 
1161           i = 0;
1162           m = info->mreq;
1163           while (m) {
1164                     i += m->m_len;
1165                     m = m->m_next;
1166           }
1167           req->r_mrest = info->mreq;
1168           req->r_mrest_len = i;
1169 
1170           /*
1171            * The presence of a non-NULL r_info in req indicates
1172            * async completion via our helper threads.  See the receiver
1173            * code.
1174            */
1175           if (info->bio) {
1176                     req->r_info = info;
1177                     req->r_flags = R_ASYNC;
1178           } else {
1179                     req->r_info = NULL;
1180                     req->r_flags = 0;
1181           }
1182           info->req = req;
1183           return(0);
1184 }
1185 
1186 static int
nfs_request_auth(struct nfsreq * rep)1187 nfs_request_auth(struct nfsreq *rep)
1188 {
1189           struct nfsmount *nmp = rep->r_nmp;
1190           struct mbuf *m;
1191           char nickv[RPCX_NICKVERF];
1192           int error = 0, auth_len, auth_type;
1193           int verf_len;
1194           u_int32_t xid;
1195           char *auth_str, *verf_str;
1196           struct ucred *cred;
1197 
1198           cred = rep->r_cred;
1199           rep->r_failed_auth = 0;
1200 
1201           /*
1202            * Get the RPC header with authorization.
1203            */
1204           verf_str = auth_str = NULL;
1205           verf_len = 0;
1206           if (nmp->nm_flag & NFSMNT_KERB) {
1207                     verf_str = nickv;
1208                     verf_len = sizeof (nickv);
1209                     auth_type = RPCAUTH_KERB4;
1210                     bzero((caddr_t)rep->r_key, sizeof(rep->r_key));
1211                     if (rep->r_failed_auth ||
1212                         nfs_getnickauth(nmp, cred, &auth_str, &auth_len,
1213                                             verf_str, verf_len)) {
1214                               error = nfs_getauth(nmp, rep, cred, &auth_str,
1215                                         &auth_len, verf_str, &verf_len, rep->r_key);
1216                               if (error) {
1217                                         m_freem(rep->r_mrest);
1218                                         rep->r_mrest = NULL;
1219                                         kfree((caddr_t)rep, M_NFSREQ);
1220                                         return (error);
1221                               }
1222                     }
1223           } else {
1224                     auth_type = RPCAUTH_UNIX;
1225                     if (cred->cr_ngroups < 1)
1226                               panic("nfsreq nogrps");
1227                     auth_len = ((((cred->cr_ngroups - 1) > nmp->nm_numgrps) ?
1228                               nmp->nm_numgrps : (cred->cr_ngroups - 1)) << 2) +
1229                               5 * NFSX_UNSIGNED;
1230           }
1231           if (rep->r_mrest)
1232                     nfs_checkpkt(rep->r_mrest, rep->r_mrest_len);
1233           m = nfsm_rpchead(cred, nmp->nm_flag, rep->r_procnum, auth_type,
1234                               auth_len, auth_str, verf_len, verf_str,
1235                               rep->r_mrest, rep->r_mrest_len, &rep->r_mheadend, &xid);
1236           rep->r_mrest = NULL;
1237           if (auth_str)
1238                     kfree(auth_str, M_TEMP);
1239 
1240           /*
1241            * For stream protocols, insert a Sun RPC Record Mark.
1242            */
1243           if (nmp->nm_sotype == SOCK_STREAM) {
1244                     M_PREPEND(m, NFSX_UNSIGNED, M_WAITOK);
1245                     *mtod(m, u_int32_t *) = htonl(0x80000000 |
1246                                (m->m_pkthdr.len - NFSX_UNSIGNED));
1247           }
1248 
1249           nfs_checkpkt(m, m->m_pkthdr.len);
1250 
1251           rep->r_mreq = m;
1252           rep->r_xid = xid;
1253           return (0);
1254 }
1255 
1256 static int
nfs_request_try(struct nfsreq * rep)1257 nfs_request_try(struct nfsreq *rep)
1258 {
1259           struct nfsmount *nmp = rep->r_nmp;
1260           struct mbuf *m2;
1261           int error;
1262 
1263           /*
1264            * Request is not on any queue, only the owner has access to it
1265            * so it should not be locked by anyone atm.
1266            *
1267            * Interlock to prevent races.  While locked the only remote
1268            * action possible is for r_mrep to be set (once we enqueue it).
1269            */
1270           if (rep->r_flags == 0xdeadc0de) {
1271                     print_backtrace(-1);
1272                     panic("flags nbad");
1273           }
1274           KKASSERT((rep->r_flags & (R_LOCKED | R_ONREQQ)) == 0);
1275           if (nmp->nm_flag & NFSMNT_SOFT)
1276                     rep->r_retry = nmp->nm_retry;
1277           else
1278                     rep->r_retry = NFS_MAXREXMIT + 1;       /* past clip limit */
1279           rep->r_rtt = rep->r_rexmit = 0;
1280           if (proct[rep->r_procnum] > 0)
1281                     rep->r_flags |= R_TIMING | R_LOCKED;
1282           else
1283                     rep->r_flags |= R_LOCKED;
1284           rep->r_mrep = NULL;
1285 
1286           nfsstats.rpcrequests++;
1287 
1288           if (nmp->nm_flag & NFSMNT_FORCE) {
1289                     rep->r_flags |= R_SOFTTERM;
1290                     rep->r_flags &= ~R_LOCKED;
1291                     if (rep->r_info)
1292                               rep->r_info->error = EINTR;
1293                     return (0);
1294           }
1295           rep->r_flags |= R_NEEDSXMIT;  /* in case send lock races us */
1296 
1297           /*
1298            * Do the client side RPC.
1299            *
1300            * Chain request into list of outstanding requests. Be sure
1301            * to put it LAST so timer finds oldest requests first.  Note
1302            * that our control of R_LOCKED prevents the request from
1303            * getting ripped out from under us or transmitted by the
1304            * timer code.
1305            *
1306            * For requests with info structures we must atomically set the
1307            * info's state because the structure could become invalid upon
1308            * return due to races (i.e., if async)
1309            */
1310           crit_enter();
1311           mtx_link_init(&rep->r_link);
1312           KKASSERT((rep->r_flags & R_ONREQQ) == 0);
1313           TAILQ_INSERT_TAIL(&nmp->nm_reqq, rep, r_chain);
1314           rep->r_flags |= R_ONREQQ;
1315           ++nmp->nm_reqqlen;
1316           if (rep->r_flags & R_ASYNC)
1317                     rep->r_info->state = NFSM_STATE_WAITREPLY;
1318           crit_exit();
1319 
1320           error = 0;
1321 
1322           /*
1323            * Send if we can.  Congestion control is not handled here any more
1324            * becausing trying to defer the initial send based on the nfs_timer
1325            * requires having a very fast nfs_timer, which is silly.
1326            */
1327           if (nmp->nm_so) {
1328                     if (nmp->nm_soflags & PR_CONNREQUIRED)
1329                               error = nfs_sndlock(nmp, rep);
1330                     if (error == 0 && (rep->r_flags & R_NEEDSXMIT)) {
1331                               m2 = m_copym(rep->r_mreq, 0, M_COPYALL, M_WAITOK);
1332                               error = nfs_send(nmp->nm_so, nmp->nm_nam, m2, rep);
1333                               rep->r_flags &= ~R_NEEDSXMIT;
1334                               if ((rep->r_flags & R_SENT) == 0) {
1335                                         rep->r_flags |= R_SENT;
1336                               }
1337                               if (nmp->nm_soflags & PR_CONNREQUIRED)
1338                                         nfs_sndunlock(nmp);
1339                     }
1340           } else {
1341                     rep->r_rtt = -1;
1342           }
1343           if (error == EPIPE)
1344                     error = 0;
1345 
1346           /*
1347            * Release the lock.  The only remote action that may have occurred
1348            * would have been the setting of rep->r_mrep.  If this occured
1349            * and the request was async we have to move it to the reader
1350            * thread's queue for action.
1351            *
1352            * For async requests also make sure the reader is woken up so
1353            * it gets on the socket to read responses.
1354            */
1355           crit_enter();
1356           if (rep->r_flags & R_ASYNC) {
1357                     if (rep->r_mrep)
1358                               nfs_hardterm(rep, 1);
1359                     rep->r_flags &= ~R_LOCKED;
1360                     nfssvc_iod_reader_wakeup(nmp);
1361           } else {
1362                     rep->r_flags &= ~R_LOCKED;
1363           }
1364           if (rep->r_flags & R_WANTED) {
1365                     rep->r_flags &= ~R_WANTED;
1366                     wakeup(rep);
1367           }
1368           crit_exit();
1369           return (error);
1370 }
1371 
1372 /*
1373  * This code is only called for synchronous requests.  Completed synchronous
1374  * requests are left on reqq and we remove them before moving on to the
1375  * processing state.
1376  */
1377 static int
nfs_request_waitreply(struct nfsreq * rep)1378 nfs_request_waitreply(struct nfsreq *rep)
1379 {
1380           struct nfsmount *nmp = rep->r_nmp;
1381           int error;
1382 
1383           KKASSERT((rep->r_flags & R_ASYNC) == 0);
1384 
1385           /*
1386            * Wait until the request is finished.
1387            */
1388           error = nfs_reply(nmp, rep);
1389 
1390           /*
1391            * RPC done, unlink the request, but don't rip it out from under
1392            * the callout timer.
1393            *
1394            * Once unlinked no other receiver or the timer will have
1395            * visibility, so we do not have to set R_LOCKED.
1396            */
1397           crit_enter();
1398           while (rep->r_flags & R_LOCKED) {
1399                     rep->r_flags |= R_WANTED;
1400                     tsleep(rep, 0, "nfstrac", 0);
1401           }
1402           KKASSERT(rep->r_flags & R_ONREQQ);
1403           TAILQ_REMOVE(&nmp->nm_reqq, rep, r_chain);
1404           rep->r_flags &= ~R_ONREQQ;
1405           --nmp->nm_reqqlen;
1406           if (TAILQ_FIRST(&nmp->nm_bioq) &&
1407               nmp->nm_reqqlen <= nfs_maxasyncbio * 2 / 3) {
1408                     nfssvc_iod_writer_wakeup(nmp);
1409           }
1410           crit_exit();
1411 
1412           /*
1413            * Decrement the outstanding request count.
1414            */
1415           if (rep->r_flags & R_SENT) {
1416                     rep->r_flags &= ~R_SENT;
1417           }
1418           return (error);
1419 }
1420 
1421 /*
1422  * Process reply with error returned from nfs_requet_waitreply().
1423  *
1424  * Returns EAGAIN if it wants us to loop up to nfs_request_try() again.
1425  * Returns ENEEDAUTH if it wants us to loop up to nfs_request_auth() again.
1426  */
1427 static int
nfs_request_processreply(nfsm_info_t info,int error)1428 nfs_request_processreply(nfsm_info_t info, int error)
1429 {
1430           struct nfsreq *req = info->req;
1431           struct nfsmount *nmp = req->r_nmp;
1432           u_int32_t *tl;
1433           int verf_type;
1434           int i;
1435 
1436           /*
1437            * If there was a successful reply and a tprintf msg.
1438            * tprintf a response.
1439            */
1440           if (error == 0 && (req->r_flags & R_TPRINTFMSG)) {
1441                     nfs_msg(req->r_td,
1442                               nmp->nm_mountp->mnt_stat.f_mntfromname,
1443                               "is alive again");
1444           }
1445 
1446           /*
1447            * Assign response and handle any pre-process error.  Response
1448            * fields can be NULL if an error is already pending.
1449            */
1450           info->mrep = req->r_mrep;
1451           info->md = req->r_md;
1452           info->dpos = req->r_dpos;
1453 
1454           if (error) {
1455                     m_freem(req->r_mreq);
1456                     req->r_mreq = NULL;
1457                     kfree(req, M_NFSREQ);
1458                     info->req = NULL;
1459                     return (error);
1460           }
1461 
1462           /*
1463            * break down the rpc header and check if ok
1464            */
1465           NULLOUT(tl = nfsm_dissect(info, 3 * NFSX_UNSIGNED));
1466           if (*tl++ == rpc_msgdenied) {
1467                     if (*tl == rpc_mismatch) {
1468                               error = EOPNOTSUPP;
1469                     } else if ((nmp->nm_flag & NFSMNT_KERB) &&
1470                                  *tl++ == rpc_autherr) {
1471                               if (req->r_failed_auth == 0) {
1472                                         req->r_failed_auth++;
1473                                         req->r_mheadend->m_next = NULL;
1474                                         m_freem(info->mrep);
1475                                         info->mrep = NULL;
1476                                         m_freem(req->r_mreq);
1477                                         req->r_mreq = NULL;
1478                                         return (ENEEDAUTH);
1479                               } else {
1480                                         error = EAUTH;
1481                               }
1482                     } else {
1483                               error = EACCES;
1484                     }
1485                     m_freem(info->mrep);
1486                     info->mrep = NULL;
1487                     m_freem(req->r_mreq);
1488                     req->r_mreq = NULL;
1489                     kfree(req, M_NFSREQ);
1490                     info->req = NULL;
1491                     return (error);
1492           }
1493 
1494           /*
1495            * Grab any Kerberos verifier, otherwise just throw it away.
1496            */
1497           verf_type = fxdr_unsigned(int, *tl++);
1498           i = fxdr_unsigned(int32_t, *tl);
1499           if ((nmp->nm_flag & NFSMNT_KERB) && verf_type == RPCAUTH_KERB4) {
1500                     error = nfs_savenickauth(nmp, req->r_cred, i, req->r_key,
1501                                                    &info->md, &info->dpos, info->mrep);
1502                     if (error)
1503                               goto nfsmout;
1504           } else if (i > 0) {
1505                     ERROROUT(nfsm_adv(info, nfsm_rndup(i)));
1506           }
1507           NULLOUT(tl = nfsm_dissect(info, NFSX_UNSIGNED));
1508           /* 0 == ok */
1509           if (*tl == 0) {
1510                     NULLOUT(tl = nfsm_dissect(info, NFSX_UNSIGNED));
1511                     if (*tl != 0) {
1512                               error = fxdr_unsigned(int, *tl);
1513 
1514                               /*
1515                                * Does anyone even implement this?  Just impose
1516                                * a 1-second delay.
1517                                */
1518                               if ((nmp->nm_flag & NFSMNT_NFSV3) &&
1519                                         error == NFSERR_TRYLATER) {
1520                                         m_freem(info->mrep);
1521                                         info->mrep = NULL;
1522                                         error = 0;
1523 
1524                                         tsleep((caddr_t)&lbolt, 0, "nqnfstry", 0);
1525                                         return (EAGAIN);    /* goto tryagain */
1526                               }
1527 
1528 #if 0
1529                               /*
1530                                * XXX We can't do this here any more because the
1531                                *     caller may be holding a shared lock on the
1532                                *     namecache entry.
1533                                *
1534                                * If the File Handle was stale, invalidate the
1535                                * lookup cache, just in case.
1536                                *
1537                                * To avoid namecache<->vnode deadlocks we must
1538                                * release the vnode lock if we hold it.
1539                                */
1540                               if (error == ESTALE) {
1541                                         struct vnode *vp = req->r_vp;
1542                                         int ltype;
1543 
1544                                         ltype = lockstatus(&vp->v_lock, curthread);
1545                                         if (ltype == LK_EXCLUSIVE || ltype == LK_SHARED)
1546                                                   lockmgr(&vp->v_lock, LK_RELEASE);
1547                                         cache_inval_vp(vp, CINV_CHILDREN);
1548                                         if (ltype == LK_EXCLUSIVE || ltype == LK_SHARED)
1549                                                   lockmgr(&vp->v_lock, ltype);
1550                               }
1551 #endif
1552                               if (nmp->nm_flag & NFSMNT_NFSV3) {
1553                                         KKASSERT(*req->r_mrp == info->mrep);
1554                                         KKASSERT(*req->r_mdp == info->md);
1555                                         KKASSERT(*req->r_dposp == info->dpos);
1556                                         error |= NFSERR_RETERR;
1557                               } else {
1558                                         m_freem(info->mrep);
1559                                         info->mrep = NULL;
1560                               }
1561                               m_freem(req->r_mreq);
1562                               req->r_mreq = NULL;
1563                               kfree(req, M_NFSREQ);
1564                               info->req = NULL;
1565                               return (error);
1566                     }
1567 
1568                     KKASSERT(*req->r_mrp == info->mrep);
1569                     KKASSERT(*req->r_mdp == info->md);
1570                     KKASSERT(*req->r_dposp == info->dpos);
1571                     m_freem(req->r_mreq);
1572                     req->r_mreq = NULL;
1573                     kfree(req, M_NFSREQ);
1574                     return (0);
1575           }
1576           m_freem(info->mrep);
1577           info->mrep = NULL;
1578           error = EPROTONOSUPPORT;
1579 nfsmout:
1580           m_freem(req->r_mreq);
1581           req->r_mreq = NULL;
1582           kfree(req, M_NFSREQ);
1583           info->req = NULL;
1584           return (error);
1585 }
1586 
1587 #ifndef NFS_NOSERVER
1588 /*
1589  * Generate the rpc reply header
1590  * siz arg. is used to decide if adding a cluster is worthwhile
1591  */
1592 int
nfs_rephead(int siz,struct nfsrv_descript * nd,struct nfssvc_sock * slp,int err,struct mbuf ** mrq,struct mbuf ** mbp,caddr_t * bposp)1593 nfs_rephead(int siz, struct nfsrv_descript *nd, struct nfssvc_sock *slp,
1594               int err, struct mbuf **mrq, struct mbuf **mbp, caddr_t *bposp)
1595 {
1596           u_int32_t *tl;
1597           struct nfsm_info info;
1598 
1599           siz += RPC_REPLYSIZ;
1600           info.mb = m_getl(max_hdr + siz, M_WAITOK, MT_DATA, M_PKTHDR, NULL);
1601           info.mreq = info.mb;
1602           info.mreq->m_pkthdr.len = 0;
1603           /*
1604            * If this is not a cluster, try and leave leading space
1605            * for the lower level headers.
1606            */
1607           if ((max_hdr + siz) < MINCLSIZE)
1608                     info.mreq->m_data += max_hdr;
1609           tl = mtod(info.mreq, u_int32_t *);
1610           info.mreq->m_len = 6 * NFSX_UNSIGNED;
1611           info.bpos = ((caddr_t)tl) + info.mreq->m_len;
1612           *tl++ = txdr_unsigned(nd->nd_retxid);
1613           *tl++ = rpc_reply;
1614           if (err == ERPCMISMATCH || (err & NFSERR_AUTHERR)) {
1615                     *tl++ = rpc_msgdenied;
1616                     if (err & NFSERR_AUTHERR) {
1617                               *tl++ = rpc_autherr;
1618                               *tl = txdr_unsigned(err & ~NFSERR_AUTHERR);
1619                               info.mreq->m_len -= NFSX_UNSIGNED;
1620                               info.bpos -= NFSX_UNSIGNED;
1621                     } else {
1622                               *tl++ = rpc_mismatch;
1623                               *tl++ = txdr_unsigned(RPC_VER2);
1624                               *tl = txdr_unsigned(RPC_VER2);
1625                     }
1626           } else {
1627                     *tl++ = rpc_msgaccepted;
1628 
1629                     /*
1630                      * For Kerberos authentication, we must send the nickname
1631                      * verifier back, otherwise just RPCAUTH_NULL.
1632                      */
1633                     if (nd->nd_flag & ND_KERBFULL) {
1634                         struct nfsuid *nuidp;
1635                         struct timeval ktvout;
1636 
1637                         for (nuidp = NUIDHASH(slp, nd->nd_cr.cr_uid)->lh_first;
1638                               nuidp != NULL; nuidp = nuidp->nu_hash.le_next) {
1639                               if (nuidp->nu_cr.cr_uid == nd->nd_cr.cr_uid &&
1640                                   (!nd->nd_nam2 || netaddr_match(AF_INET,
1641                                    &nuidp->nu_haddr, nd->nd_nam2)))
1642                                   break;
1643                         }
1644                         if (nuidp) {
1645                               /*
1646                                * Encrypt the timestamp in ecb mode using the
1647                                * session key.
1648                                */
1649 #ifdef NFSKERB
1650                               XXX
1651 #else
1652                               ktvout.tv_sec = 0;
1653                               ktvout.tv_usec = 0;
1654 #endif
1655 
1656                               *tl++ = rpc_auth_kerb;
1657                               *tl++ = txdr_unsigned(3 * NFSX_UNSIGNED);
1658                               *tl = ktvout.tv_sec;
1659                               tl = nfsm_build(&info, 3 * NFSX_UNSIGNED);
1660                               *tl++ = ktvout.tv_usec;
1661                               *tl++ = txdr_unsigned(nuidp->nu_cr.cr_uid);
1662                         } else {
1663                               *tl++ = 0;
1664                               *tl++ = 0;
1665                         }
1666                     } else {
1667                               *tl++ = 0;
1668                               *tl++ = 0;
1669                     }
1670                     switch (err) {
1671                     case EPROGUNAVAIL:
1672                               *tl = txdr_unsigned(RPC_PROGUNAVAIL);
1673                               break;
1674                     case EPROGMISMATCH:
1675                               *tl = txdr_unsigned(RPC_PROGMISMATCH);
1676                               tl = nfsm_build(&info, 2 * NFSX_UNSIGNED);
1677                               *tl++ = txdr_unsigned(2);
1678                               *tl = txdr_unsigned(3);
1679                               break;
1680                     case EPROCUNAVAIL:
1681                               *tl = txdr_unsigned(RPC_PROCUNAVAIL);
1682                               break;
1683                     case EBADRPC:
1684                               *tl = txdr_unsigned(RPC_GARBAGE);
1685                               break;
1686                     default:
1687                               *tl = 0;
1688                               if (err != NFSERR_RETVOID) {
1689                                         tl = nfsm_build(&info, NFSX_UNSIGNED);
1690                                         if (err)
1691                                             *tl = txdr_unsigned(nfsrv_errmap(nd, err));
1692                                         else
1693                                             *tl = 0;
1694                               }
1695                               break;
1696                     }
1697           }
1698 
1699           if (mrq != NULL)
1700               *mrq = info.mreq;
1701           *mbp = info.mb;
1702           *bposp = info.bpos;
1703           if (err != 0 && err != NFSERR_RETVOID)
1704                     nfsstats.srvrpc_errs++;
1705           return (0);
1706 }
1707 
1708 
1709 #endif /* NFS_NOSERVER */
1710 
1711 /*
1712  * Nfs timer routine.
1713  *
1714  * Scan the nfsreq list and retranmit any requests that have timed out
1715  * To avoid retransmission attempts on STREAM sockets (in the future) make
1716  * sure to set the r_retry field to 0 (implies nm_retry == 0).
1717  *
1718  * Requests with attached responses, terminated requests, and
1719  * locked requests are ignored.  Locked requests will be picked up
1720  * in a later timer call.
1721  */
1722 void
nfs_timer_callout(void * arg)1723 nfs_timer_callout(void *arg /* never used */)
1724 {
1725           struct nfsmount *nmp;
1726           struct nfsreq *req;
1727 #ifndef NFS_NOSERVER
1728           struct nfssvc_sock *slp;
1729           u_quad_t cur_usec;
1730 #endif /* NFS_NOSERVER */
1731 
1732           lwkt_gettoken(&nfs_token);
1733           TAILQ_FOREACH(nmp, &nfs_mountq, nm_entry) {
1734                     lwkt_gettoken(&nmp->nm_token);
1735                     TAILQ_FOREACH(req, &nmp->nm_reqq, r_chain) {
1736                               KKASSERT(nmp == req->r_nmp);
1737                               if (req->r_mrep)
1738                                         continue;
1739                               if (req->r_flags & (R_SOFTTERM | R_LOCKED))
1740                                         continue;
1741 
1742                               /*
1743                                * Handle timeout/retry.  Be sure to process r_mrep
1744                                * for async requests that completed while we had
1745                                * the request locked or they will hang in the reqq
1746                                * forever.
1747                                */
1748                               req->r_flags |= R_LOCKED;
1749                               if (nfs_sigintr(nmp, req, req->r_td)) {
1750                                         nfs_softterm(req, 1);
1751                                         req->r_flags &= ~R_LOCKED;
1752                               } else {
1753                                         nfs_timer_req(req);
1754                                         if (req->r_flags & R_ASYNC) {
1755                                                   if (req->r_mrep)
1756                                                             nfs_hardterm(req, 1);
1757                                                   req->r_flags &= ~R_LOCKED;
1758                                                   nfssvc_iod_reader_wakeup(nmp);
1759                                         } else {
1760                                                   req->r_flags &= ~R_LOCKED;
1761                                         }
1762                               }
1763                               if (req->r_flags & R_WANTED) {
1764                                         req->r_flags &= ~R_WANTED;
1765                                         wakeup(req);
1766                               }
1767                     }
1768                     lwkt_reltoken(&nmp->nm_token);
1769           }
1770 #ifndef NFS_NOSERVER
1771 
1772           /*
1773            * Scan the write gathering queues for writes that need to be
1774            * completed now.
1775            */
1776           cur_usec = nfs_curusec();
1777 
1778           TAILQ_FOREACH(slp, &nfssvc_sockhead, ns_chain) {
1779                     /* XXX race against removal */
1780                     if (lwkt_trytoken(&slp->ns_token)) {
1781                               if (slp->ns_tq.lh_first &&
1782                                   (slp->ns_tq.lh_first->nd_time <= cur_usec)) {
1783                                         nfsrv_wakenfsd(slp, 1);
1784                               }
1785                               lwkt_reltoken(&slp->ns_token);
1786                     }
1787           }
1788 #endif /* NFS_NOSERVER */
1789 
1790           callout_reset(&nfs_timer_handle, nfs_ticks, nfs_timer_callout, NULL);
1791           lwkt_reltoken(&nfs_token);
1792 }
1793 
1794 static
1795 void
nfs_timer_req(struct nfsreq * req)1796 nfs_timer_req(struct nfsreq *req)
1797 {
1798           struct thread *td = &thread0; /* XXX for creds, will break if sleep */
1799           struct nfsmount *nmp = req->r_nmp;
1800           struct mbuf *m;
1801           struct socket *so;
1802           int timeo;
1803           int error;
1804 
1805           /*
1806            * rtt ticks and timeout calculation.  Return if the timeout
1807            * has not been reached yet, unless the packet is flagged
1808            * for an immediate send.
1809            *
1810            * The mean rtt doesn't help when we get random I/Os, we have
1811            * to multiply by fairly large numbers.
1812            */
1813           if (req->r_rtt >= 0) {
1814                     /*
1815                      * Calculate the timeout to test against.
1816                      */
1817                     req->r_rtt++;
1818                     if (nmp->nm_flag & NFSMNT_DUMBTIMR) {
1819                               timeo = nmp->nm_timeo << NFS_RTT_SCALE_BITS;
1820                     } else if (req->r_flags & R_TIMING) {
1821                               timeo = NFS_SRTT(req) + NFS_SDRTT(req);
1822                     } else {
1823                               timeo = nmp->nm_timeo << NFS_RTT_SCALE_BITS;
1824                     }
1825                     timeo *= multt[req->r_procnum];
1826                     /* timeo is still scaled by SCALE_BITS */
1827 
1828 #define NFSFS       (NFS_RTT_SCALE * NFS_HZ)
1829                     if (req->r_flags & R_TIMING) {
1830                               static long last_time;
1831                               if (nfs_showrtt && last_time != time_uptime) {
1832                                         kprintf("rpccmd %d NFS SRTT %d SDRTT %d "
1833                                                   "timeo %d.%03d\n",
1834                                                   proct[req->r_procnum],
1835                                                   NFS_SRTT(req), NFS_SDRTT(req),
1836                                                   timeo / NFSFS,
1837                                                   timeo % NFSFS * 1000 /  NFSFS);
1838                                         last_time = time_uptime;
1839                               }
1840                     }
1841 #undef NFSFS
1842 
1843                     /*
1844                      * deal with nfs_timer jitter.
1845                      */
1846                     timeo = (timeo >> NFS_RTT_SCALE_BITS) + 1;
1847                     if (timeo < 2)
1848                               timeo = 2;
1849 
1850                     if (nmp->nm_timeouts > 0)
1851                               timeo *= nfs_backoff[nmp->nm_timeouts - 1];
1852                     if (timeo > NFS_MAXTIMEO)
1853                               timeo = NFS_MAXTIMEO;
1854                     if (req->r_rtt <= timeo) {
1855                               if ((req->r_flags & R_NEEDSXMIT) == 0)
1856                                         return;
1857                     } else if (nmp->nm_timeouts < 8) {
1858                               nmp->nm_timeouts++;
1859                     }
1860           }
1861 
1862           /*
1863            * Check for server not responding
1864            */
1865           if ((req->r_flags & R_TPRINTFMSG) == 0 &&
1866                req->r_rexmit > nmp->nm_deadthresh) {
1867                     nfs_msg(req->r_td, nmp->nm_mountp->mnt_stat.f_mntfromname,
1868                               "not responding");
1869                     req->r_flags |= R_TPRINTFMSG;
1870           }
1871           if (req->r_rexmit >= req->r_retry) {    /* too many */
1872                     nfsstats.rpctimeouts++;
1873                     nfs_softterm(req, 1);
1874                     return;
1875           }
1876 
1877           /*
1878            * Generally disable retransmission on reliable sockets,
1879            * unless the request is flagged for immediate send.
1880            */
1881           if (nmp->nm_sotype != SOCK_DGRAM) {
1882                     if (++req->r_rexmit > NFS_MAXREXMIT)
1883                               req->r_rexmit = NFS_MAXREXMIT;
1884                     if ((req->r_flags & R_NEEDSXMIT) == 0)
1885                               return;
1886           }
1887 
1888           /*
1889            * Stop here if we do not have a socket!
1890            */
1891           if ((so = nmp->nm_so) == NULL)
1892                     return;
1893 
1894           /*
1895            * If there is enough space and the window allows.. resend it.
1896            *
1897            * r_rtt is left intact in case we get an answer after the
1898            * retry that was a reply to the original packet.
1899            *
1900            * NOTE: so_pru_send()
1901            */
1902           if (ssb_space(&so->so_snd) >= req->r_mreq->m_pkthdr.len &&
1903               (req->r_flags & (R_SENT | R_NEEDSXMIT)) &&
1904              (m = m_copym(req->r_mreq, 0, M_COPYALL, M_NOWAIT))){
1905                     if ((nmp->nm_flag & NFSMNT_NOCONN) == 0)
1906                         error = so_pru_send(so, 0, m, NULL, NULL, td);
1907                     else
1908                         error = so_pru_send(so, 0, m, nmp->nm_nam, NULL, td);
1909                     if (error) {
1910                               if (NFSIGNORE_SOERROR(nmp->nm_soflags, error))
1911                                         so->so_error = 0;
1912                               req->r_flags |= R_NEEDSXMIT;
1913                     } else if (req->r_mrep == NULL) {
1914                               /*
1915                                * Iff first send, start timing
1916                                * else turn timing off, backoff timer
1917                                * and divide congestion window by 2.
1918                                *
1919                                * It is possible for the so_pru_send() to
1920                                * block and for us to race a reply so we
1921                                * only do this if the reply field has not
1922                                * been filled in.  R_LOCKED will prevent
1923                                * the request from being ripped out from under
1924                                * us entirely.
1925                                *
1926                                * Record the last resent procnum to aid us
1927                                * in duplicate detection on receive.
1928                                */
1929                               if ((req->r_flags & R_NEEDSXMIT) == 0) {
1930                                         if (nfs_showrexmit)
1931                                                   kprintf("X");
1932                                         if (++req->r_rexmit > NFS_MAXREXMIT)
1933                                                   req->r_rexmit = NFS_MAXREXMIT;
1934                                         nmp->nm_maxasync_scaled >>= 1;
1935                                         if (nmp->nm_maxasync_scaled < NFS_MINASYNC_SCALED)
1936                                                   nmp->nm_maxasync_scaled = NFS_MINASYNC_SCALED;
1937                                         nfsstats.rpcretries++;
1938                                         nmp->nm_lastreprocnum = req->r_procnum;
1939                               } else {
1940                                         req->r_flags |= R_SENT;
1941                                         req->r_flags &= ~R_NEEDSXMIT;
1942                               }
1943                     }
1944           }
1945 }
1946 
1947 /*
1948  * Mark all of an nfs mount's outstanding requests with R_SOFTTERM and
1949  * wait for all requests to complete. This is used by forced unmounts
1950  * to terminate any outstanding RPCs.
1951  *
1952  * Locked requests cannot be canceled but will be marked for
1953  * soft-termination.
1954  */
1955 int
nfs_nmcancelreqs(struct nfsmount * nmp)1956 nfs_nmcancelreqs(struct nfsmount *nmp)
1957 {
1958           struct nfsreq *req;
1959           int i;
1960 
1961           crit_enter();
1962           TAILQ_FOREACH(req, &nmp->nm_reqq, r_chain) {
1963                     if (req->r_mrep != NULL || (req->r_flags & R_SOFTTERM))
1964                               continue;
1965                     nfs_softterm(req, 0);
1966           }
1967           /* XXX  the other two queues as well */
1968           crit_exit();
1969 
1970           for (i = 0; i < 30; i++) {
1971                     crit_enter();
1972                     TAILQ_FOREACH(req, &nmp->nm_reqq, r_chain) {
1973                               if (nmp == req->r_nmp)
1974                                         break;
1975                     }
1976                     crit_exit();
1977                     if (req == NULL)
1978                               return (0);
1979                     tsleep(&lbolt, 0, "nfscancel", 0);
1980           }
1981           return (EBUSY);
1982 }
1983 
1984 /*
1985  * Soft-terminate a request, effectively marking it as failed.
1986  *
1987  * Must be called from within a critical section.
1988  */
1989 static void
nfs_softterm(struct nfsreq * rep,int islocked)1990 nfs_softterm(struct nfsreq *rep, int islocked)
1991 {
1992           rep->r_flags |= R_SOFTTERM;
1993           if (rep->r_info)
1994                     rep->r_info->error = EINTR;
1995           nfs_hardterm(rep, islocked);
1996 }
1997 
1998 /*
1999  * Hard-terminate a request, typically after getting a response.
2000  *
2001  * The state machine can still decide to re-issue it later if necessary.
2002  *
2003  * Must be called from within a critical section.
2004  */
2005 static void
nfs_hardterm(struct nfsreq * rep,int islocked)2006 nfs_hardterm(struct nfsreq *rep, int islocked)
2007 {
2008           struct nfsmount *nmp = rep->r_nmp;
2009 
2010           /*
2011            * The nm_send count is decremented now to avoid deadlocks
2012            * when the process in soreceive() hasn't yet managed to send
2013            * its own request.
2014            */
2015           if (rep->r_flags & R_SENT) {
2016                     rep->r_flags &= ~R_SENT;
2017           }
2018 
2019           /*
2020            * If we locked the request or nobody else has locked the request,
2021            * and the request is async, we can move it to the reader thread's
2022            * queue now and fix up the state.
2023            *
2024            * If we locked the request or nobody else has locked the request,
2025            * we can wake up anyone blocked waiting for a response on the
2026            * request.
2027            */
2028           if (islocked || (rep->r_flags & R_LOCKED) == 0) {
2029                     if ((rep->r_flags & (R_ONREQQ | R_ASYNC)) ==
2030                         (R_ONREQQ | R_ASYNC)) {
2031                               rep->r_flags &= ~R_ONREQQ;
2032                               TAILQ_REMOVE(&nmp->nm_reqq, rep, r_chain);
2033                               --nmp->nm_reqqlen;
2034                               TAILQ_INSERT_TAIL(&nmp->nm_reqrxq, rep, r_chain);
2035                               KKASSERT(rep->r_info->state == NFSM_STATE_TRY ||
2036                                          rep->r_info->state == NFSM_STATE_WAITREPLY);
2037 
2038                               /*
2039                                * When setting the state to PROCESSREPLY we must
2040                                * roll-up any error not related to the contents of
2041                                * the reply (i.e. if there is no contents).
2042                                */
2043                               rep->r_info->state = NFSM_STATE_PROCESSREPLY;
2044                               nfssvc_iod_reader_wakeup(nmp);
2045                               if (TAILQ_FIRST(&nmp->nm_bioq) &&
2046                                   nmp->nm_reqqlen <= nfs_maxasyncbio * 2 / 3) {
2047                                         nfssvc_iod_writer_wakeup(nmp);
2048                               }
2049                     }
2050                     mtx_abort_link(&nmp->nm_rxlock, &rep->r_link);
2051           }
2052 }
2053 
2054 /*
2055  * Test for a termination condition pending on the process.
2056  * This is used for NFSMNT_INT mounts.
2057  */
2058 int
nfs_sigintr(struct nfsmount * nmp,struct nfsreq * rep,struct thread * td)2059 nfs_sigintr(struct nfsmount *nmp, struct nfsreq *rep, struct thread *td)
2060 {
2061           sigset_t tmpset;
2062           struct proc *p;
2063           struct lwp *lp;
2064 
2065           if (rep && (rep->r_flags & R_SOFTTERM))
2066                     return (EINTR);
2067           /* Terminate all requests while attempting a forced unmount. */
2068           if (nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF)
2069                     return (EINTR);
2070           if (!(nmp->nm_flag & NFSMNT_INT))
2071                     return (0);
2072           /* td might be NULL YYY */
2073           if (td == NULL || (p = td->td_proc) == NULL)
2074                     return (0);
2075 
2076           lp = td->td_lwp;
2077           tmpset = lwp_sigpend(lp);
2078           SIGSETNAND(tmpset, lp->lwp_sigmask);
2079           SIGSETNAND(tmpset, p->p_sigignore);
2080           if (SIGNOTEMPTY(tmpset) && NFSINT_SIGMASK(tmpset))
2081                     return (EINTR);
2082 
2083           return (0);
2084 }
2085 
2086 /*
2087  * Lock a socket against others.
2088  * Necessary for STREAM sockets to ensure you get an entire rpc request/reply
2089  * and also to avoid race conditions between the processes with nfs requests
2090  * in progress when a reconnect is necessary.
2091  */
2092 int
nfs_sndlock(struct nfsmount * nmp,struct nfsreq * rep)2093 nfs_sndlock(struct nfsmount *nmp, struct nfsreq *rep)
2094 {
2095           mtx_t *mtx = &nmp->nm_txlock;
2096           struct thread *td;
2097           int slptimeo;
2098           int slpflag;
2099           int error;
2100 
2101           slpflag = 0;
2102           slptimeo = 0;
2103           td = rep ? rep->r_td : NULL;
2104           if (nmp->nm_flag & NFSMNT_INT)
2105                     slpflag = PCATCH;
2106 
2107           while ((error = mtx_lock_ex_try(mtx)) != 0) {
2108                     if (nfs_sigintr(nmp, rep, td)) {
2109                               error = EINTR;
2110                               break;
2111                     }
2112                     error = mtx_lock_ex(mtx, slpflag, slptimeo);
2113                     if (error == 0)
2114                               break;
2115                     if (slpflag == PCATCH) {
2116                               slpflag = 0;
2117                               slptimeo = 2 * hz;
2118                     }
2119           }
2120           /* Always fail if our request has been cancelled. */
2121           if (rep && (rep->r_flags & R_SOFTTERM)) {
2122                     if (error == 0)
2123                               mtx_unlock(mtx);
2124                     error = EINTR;
2125           }
2126           return (error);
2127 }
2128 
2129 /*
2130  * Unlock the stream socket for others.
2131  */
2132 void
nfs_sndunlock(struct nfsmount * nmp)2133 nfs_sndunlock(struct nfsmount *nmp)
2134 {
2135           mtx_unlock(&nmp->nm_txlock);
2136 }
2137 
2138 /*
2139  * Lock the receiver side of the socket.
2140  *
2141  * rep may be NULL.
2142  */
2143 static int
nfs_rcvlock(struct nfsmount * nmp,struct nfsreq * rep)2144 nfs_rcvlock(struct nfsmount *nmp, struct nfsreq *rep)
2145 {
2146           mtx_t *mtx = &nmp->nm_rxlock;
2147           int slpflag;
2148           int slptimeo;
2149           int error;
2150 
2151           /*
2152            * Unconditionally check for completion in case another nfsiod
2153            * get the packet while the caller was blocked, before the caller
2154            * called us.  Packet reception is handled by mainline code which
2155            * is protected by the BGL at the moment.
2156            *
2157            * We do not strictly need the second check just before the
2158            * tsleep(), but it's good defensive programming.
2159            */
2160           if (rep && rep->r_mrep != NULL)
2161                     return (EALREADY);
2162 
2163           if (nmp->nm_flag & NFSMNT_INT)
2164                     slpflag = PCATCH;
2165           else
2166                     slpflag = 0;
2167           slptimeo = 0;
2168 
2169           while ((error = mtx_lock_ex_try(mtx)) != 0) {
2170                     if (nfs_sigintr(nmp, rep, (rep ? rep->r_td : NULL))) {
2171                               error = EINTR;
2172                               break;
2173                     }
2174                     if (rep && rep->r_mrep != NULL) {
2175                               error = EALREADY;
2176                               break;
2177                     }
2178 
2179                     /*
2180                      * NOTE: can return ENOLCK, but in that case rep->r_mrep
2181                      *       will already be set.
2182                      */
2183                     if (rep) {
2184                               error = mtx_lock_ex_link(mtx, &rep->r_link,
2185                                                              slpflag, slptimeo);
2186                     } else {
2187                               error = mtx_lock_ex(mtx, slpflag, slptimeo);
2188                     }
2189                     if (error == 0)
2190                               break;
2191 
2192                     /*
2193                      * If our reply was recieved while we were sleeping,
2194                      * then just return without taking the lock to avoid a
2195                      * situation where a single iod could 'capture' the
2196                      * recieve lock.
2197                      */
2198                     if (rep && rep->r_mrep != NULL) {
2199                               error = EALREADY;
2200                               break;
2201                     }
2202                     if (slpflag == PCATCH) {
2203                               slpflag = 0;
2204                               slptimeo = 2 * hz;
2205                     }
2206           }
2207           if (error == 0) {
2208                     if (rep && rep->r_mrep != NULL) {
2209                               error = EALREADY;
2210                               mtx_unlock(mtx);
2211                     }
2212           }
2213           return (error);
2214 }
2215 
2216 /*
2217  * Unlock the stream socket for others.
2218  */
2219 static void
nfs_rcvunlock(struct nfsmount * nmp)2220 nfs_rcvunlock(struct nfsmount *nmp)
2221 {
2222           mtx_unlock(&nmp->nm_rxlock);
2223 }
2224 
2225 /*
2226  * nfs_realign:
2227  *
2228  * Check for badly aligned mbuf data and realign by copying the unaligned
2229  * portion of the data into a new mbuf chain and freeing the portions
2230  * of the old chain that were replaced.
2231  *
2232  * We cannot simply realign the data within the existing mbuf chain
2233  * because the underlying buffers may contain other rpc commands and
2234  * we cannot afford to overwrite them.
2235  *
2236  * We would prefer to avoid this situation entirely.  The situation does
2237  * not occur with NFS/UDP and is supposed to only occassionally occur
2238  * with TCP.  Use vfs.nfs.realign_count and realign_test to check this.
2239  *
2240  * NOTE!  M_NOWAIT cannot be used here.  The mbufs must be acquired
2241  *          because the rpc request OR reply cannot be thrown away.  TCP NFS
2242  *          mounts do not retry their RPCs unless the TCP connection itself
2243  *          is dropped so throwing away a RPC will basically cause the NFS
2244  *          operation to lockup indefinitely.
2245  */
2246 static void
nfs_realign(struct mbuf ** pm,int hsiz)2247 nfs_realign(struct mbuf **pm, int hsiz)
2248 {
2249           struct mbuf *m;
2250           struct mbuf *n = NULL;
2251 
2252           /*
2253            * Check for misalignemnt
2254            */
2255           ++nfs_realign_test;
2256           while ((m = *pm) != NULL) {
2257                     if ((m->m_len & 0x3) || (mtod(m, intptr_t) & 0x3))
2258                               break;
2259                     pm = &m->m_next;
2260           }
2261 
2262           /*
2263            * If misalignment found make a completely new copy.
2264            */
2265           if (m) {
2266                     ++nfs_realign_count;
2267                     n = m_dup_data(m, M_WAITOK);
2268                     m_freem(*pm);
2269                     *pm = n;
2270           }
2271 }
2272 
2273 #ifndef NFS_NOSERVER
2274 
2275 /*
2276  * Parse an RPC request
2277  * - verify it
2278  * - fill in the cred struct.
2279  */
2280 int
nfs_getreq(struct nfsrv_descript * nd,struct nfsd * nfsd,int has_header)2281 nfs_getreq(struct nfsrv_descript *nd, struct nfsd *nfsd, int has_header)
2282 {
2283           int len, i;
2284           u_int32_t *tl;
2285           struct uio uio;
2286           struct iovec iov;
2287           caddr_t cp;
2288           u_int32_t nfsvers, auth_type;
2289           uid_t nickuid;
2290           int error = 0, ticklen;
2291           struct nfsuid *nuidp;
2292           struct timeval tvin, tvout;
2293           struct nfsm_info info;
2294 #if 0                                   /* until encrypted keys are implemented */
2295           NFSKERBKEYSCHED_T keys;       /* stores key schedule */
2296 #endif
2297 
2298           info.mrep = nd->nd_mrep;
2299           info.md = nd->nd_md;
2300           info.dpos = nd->nd_dpos;
2301 
2302           if (has_header) {
2303                     NULLOUT(tl = nfsm_dissect(&info, 10 * NFSX_UNSIGNED));
2304                     nd->nd_retxid = fxdr_unsigned(u_int32_t, *tl++);
2305                     if (*tl++ != rpc_call) {
2306                               m_freem(info.mrep);
2307                               return (EBADRPC);
2308                     }
2309           } else {
2310                     NULLOUT(tl = nfsm_dissect(&info, 8 * NFSX_UNSIGNED));
2311           }
2312           nd->nd_repstat = 0;
2313           nd->nd_flag = 0;
2314           if (*tl++ != rpc_vers) {
2315                     nd->nd_repstat = ERPCMISMATCH;
2316                     nd->nd_procnum = NFSPROC_NOOP;
2317                     return (0);
2318           }
2319           if (*tl != nfs_prog) {
2320                     nd->nd_repstat = EPROGUNAVAIL;
2321                     nd->nd_procnum = NFSPROC_NOOP;
2322                     return (0);
2323           }
2324           tl++;
2325           nfsvers = fxdr_unsigned(u_int32_t, *tl++);
2326           if (nfsvers < NFS_VER2 || nfsvers > NFS_VER3) {
2327                     nd->nd_repstat = EPROGMISMATCH;
2328                     nd->nd_procnum = NFSPROC_NOOP;
2329                     return (0);
2330           }
2331           if (nfsvers == NFS_VER3)
2332                     nd->nd_flag = ND_NFSV3;
2333           nd->nd_procnum = fxdr_unsigned(u_int32_t, *tl++);
2334           if (nd->nd_procnum == NFSPROC_NULL)
2335                     return (0);
2336           if (nd->nd_procnum >= NFS_NPROCS ||
2337                     (nd->nd_procnum >= NQNFSPROC_GETLEASE) ||
2338                     (!nd->nd_flag && nd->nd_procnum > NFSV2PROC_STATFS)) {
2339                     nd->nd_repstat = EPROCUNAVAIL;
2340                     nd->nd_procnum = NFSPROC_NOOP;
2341                     return (0);
2342           }
2343           if ((nd->nd_flag & ND_NFSV3) == 0)
2344                     nd->nd_procnum = nfsv3_procid[nd->nd_procnum];
2345           auth_type = *tl++;
2346           len = fxdr_unsigned(int, *tl++);
2347           if (len < 0 || len > RPCAUTH_MAXSIZ) {
2348                     m_freem(info.mrep);
2349                     return (EBADRPC);
2350           }
2351 
2352           nd->nd_flag &= ~ND_KERBAUTH;
2353           /*
2354            * Handle auth_unix or auth_kerb.
2355            */
2356           if (auth_type == rpc_auth_unix) {
2357                     len = fxdr_unsigned(int, *++tl);
2358                     if (len < 0 || len > NFS_MAXNAMLEN) {
2359                               m_freem(info.mrep);
2360                               return (EBADRPC);
2361                     }
2362                     ERROROUT(nfsm_adv(&info, nfsm_rndup(len)));
2363                     NULLOUT(tl = nfsm_dissect(&info, 3 * NFSX_UNSIGNED));
2364                     bzero((caddr_t)&nd->nd_cr, sizeof (struct ucred));
2365                     nd->nd_cr.cr_ref = 1;
2366                     nd->nd_cr.cr_uid = fxdr_unsigned(uid_t, *tl++);
2367                     nd->nd_cr.cr_ruid = nd->nd_cr.cr_svuid = nd->nd_cr.cr_uid;
2368                     nd->nd_cr.cr_gid = fxdr_unsigned(gid_t, *tl++);
2369                     nd->nd_cr.cr_rgid = nd->nd_cr.cr_svgid = nd->nd_cr.cr_gid;
2370                     len = fxdr_unsigned(int, *tl);
2371                     if (len < 0 || len > RPCAUTH_UNIXGIDS) {
2372                               m_freem(info.mrep);
2373                               return (EBADRPC);
2374                     }
2375                     NULLOUT(tl = nfsm_dissect(&info, (len + 2) * NFSX_UNSIGNED));
2376                     for (i = 1; i <= len; i++)
2377                         if (i < NGROUPS)
2378                               nd->nd_cr.cr_groups[i] = fxdr_unsigned(gid_t, *tl++);
2379                         else
2380                               tl++;
2381                     nd->nd_cr.cr_ngroups = (len >= NGROUPS) ? NGROUPS : (len + 1);
2382                     if (nd->nd_cr.cr_ngroups > 1)
2383                         nfsrvw_sort(nd->nd_cr.cr_groups, nd->nd_cr.cr_ngroups);
2384                     len = fxdr_unsigned(int, *++tl);
2385                     if (len < 0 || len > RPCAUTH_MAXSIZ) {
2386                               m_freem(info.mrep);
2387                               return (EBADRPC);
2388                     }
2389                     if (len > 0) {
2390                               ERROROUT(nfsm_adv(&info, nfsm_rndup(len)));
2391                     }
2392           } else if (auth_type == rpc_auth_kerb) {
2393                     switch (fxdr_unsigned(int, *tl++)) {
2394                     case RPCAKN_FULLNAME:
2395                               ticklen = fxdr_unsigned(int, *tl);
2396                               *((u_int32_t *)nfsd->nfsd_authstr) = *tl;
2397                               uio.uio_resid = nfsm_rndup(ticklen) + NFSX_UNSIGNED;
2398                               nfsd->nfsd_authlen = uio.uio_resid + NFSX_UNSIGNED;
2399                               if (uio.uio_resid > (len - 2 * NFSX_UNSIGNED)) {
2400                                         m_freem(info.mrep);
2401                                         return (EBADRPC);
2402                               }
2403                               uio.uio_offset = 0;
2404                               uio.uio_iov = &iov;
2405                               uio.uio_iovcnt = 1;
2406                               uio.uio_segflg = UIO_SYSSPACE;
2407                               iov.iov_base = (caddr_t)&nfsd->nfsd_authstr[4];
2408                               iov.iov_len = RPCAUTH_MAXSIZ - 4;
2409                               ERROROUT(nfsm_mtouio(&info, &uio, uio.uio_resid));
2410                               NULLOUT(tl = nfsm_dissect(&info, 2 * NFSX_UNSIGNED));
2411                               if (*tl++ != rpc_auth_kerb ||
2412                                         fxdr_unsigned(int, *tl) != 4 * NFSX_UNSIGNED) {
2413                                         kprintf("Bad kerb verifier\n");
2414                                         nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
2415                                         nd->nd_procnum = NFSPROC_NOOP;
2416                                         return (0);
2417                               }
2418                               NULLOUT(cp = nfsm_dissect(&info, 4 * NFSX_UNSIGNED));
2419                               tl = (u_int32_t *)cp;
2420                               if (fxdr_unsigned(int, *tl) != RPCAKN_FULLNAME) {
2421                                         kprintf("Not fullname kerb verifier\n");
2422                                         nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
2423                                         nd->nd_procnum = NFSPROC_NOOP;
2424                                         return (0);
2425                               }
2426                               cp += NFSX_UNSIGNED;
2427                               bcopy(cp, nfsd->nfsd_verfstr, 3 * NFSX_UNSIGNED);
2428                               nfsd->nfsd_verflen = 3 * NFSX_UNSIGNED;
2429                               nd->nd_flag |= ND_KERBFULL;
2430                               nfsd->nfsd_flag |= NFSD_NEEDAUTH;
2431                               break;
2432                     case RPCAKN_NICKNAME:
2433                               if (len != 2 * NFSX_UNSIGNED) {
2434                                         kprintf("Kerb nickname short\n");
2435                                         nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADCRED);
2436                                         nd->nd_procnum = NFSPROC_NOOP;
2437                                         return (0);
2438                               }
2439                               nickuid = fxdr_unsigned(uid_t, *tl);
2440                               NULLOUT(tl = nfsm_dissect(&info, 2 * NFSX_UNSIGNED));
2441                               if (*tl++ != rpc_auth_kerb ||
2442                                         fxdr_unsigned(int, *tl) != 3 * NFSX_UNSIGNED) {
2443                                         kprintf("Kerb nick verifier bad\n");
2444                                         nd->nd_repstat = (NFSERR_AUTHERR|AUTH_BADVERF);
2445                                         nd->nd_procnum = NFSPROC_NOOP;
2446                                         return (0);
2447                               }
2448                               NULLOUT(tl = nfsm_dissect(&info, 3 * NFSX_UNSIGNED));
2449                               tvin.tv_sec = *tl++;
2450                               tvin.tv_usec = *tl;
2451 
2452                               for (nuidp = NUIDHASH(nfsd->nfsd_slp,nickuid)->lh_first;
2453                                   nuidp != NULL; nuidp = nuidp->nu_hash.le_next) {
2454                                         if (nuidp->nu_cr.cr_uid == nickuid &&
2455                                             (!nd->nd_nam2 ||
2456                                              netaddr_match(AF_INET,
2457                                               &nuidp->nu_haddr, nd->nd_nam2)))
2458                                                   break;
2459                               }
2460                               if (!nuidp) {
2461                                         nd->nd_repstat =
2462                                                   (NFSERR_AUTHERR|AUTH_REJECTCRED);
2463                                         nd->nd_procnum = NFSPROC_NOOP;
2464                                         return (0);
2465                               }
2466 
2467                               /*
2468                                * Now, decrypt the timestamp using the session key
2469                                * and validate it.
2470                                */
2471 #ifdef NFSKERB
2472                               XXX
2473 #else
2474                               tvout.tv_sec = 0;
2475                               tvout.tv_usec = 0;
2476 #endif
2477 
2478                               tvout.tv_sec = fxdr_unsigned(long, tvout.tv_sec);
2479                               tvout.tv_usec = fxdr_unsigned(long, tvout.tv_usec);
2480                               if (nuidp->nu_expire != time_uptime ||
2481                                   nuidp->nu_timestamp.tv_sec > tvout.tv_sec ||
2482                                   (nuidp->nu_timestamp.tv_sec == tvout.tv_sec &&
2483                                    nuidp->nu_timestamp.tv_usec > tvout.tv_usec)) {
2484                                         nuidp->nu_expire = 0;
2485                                         nd->nd_repstat =
2486                                             (NFSERR_AUTHERR|AUTH_REJECTVERF);
2487                                         nd->nd_procnum = NFSPROC_NOOP;
2488                                         return (0);
2489                               }
2490                               nfsrv_setcred(&nuidp->nu_cr, &nd->nd_cr);
2491                               nd->nd_flag |= ND_KERBNICK;
2492                               break;
2493                     }
2494           } else {
2495                     nd->nd_repstat = (NFSERR_AUTHERR | AUTH_REJECTCRED);
2496                     nd->nd_procnum = NFSPROC_NOOP;
2497                     return (0);
2498           }
2499 
2500           nd->nd_md = info.md;
2501           nd->nd_dpos = info.dpos;
2502           return (0);
2503 nfsmout:
2504           return (error);
2505 }
2506 
2507 #endif
2508 
2509 /*
2510  * Send a message to the originating process's terminal.  The thread and/or
2511  * process may be NULL.  YYY the thread should not be NULL but there may
2512  * still be some uio_td's that are still being passed as NULL through to
2513  * nfsm_request().
2514  */
2515 static int
nfs_msg(struct thread * td,char * server,char * msg)2516 nfs_msg(struct thread *td, char *server, char *msg)
2517 {
2518           tpr_t tpr;
2519 
2520           if (td && td->td_proc)
2521                     tpr = tprintf_open(td->td_proc);
2522           else
2523                     tpr = NULL;
2524           tprintf(tpr, "nfs server %s: %s\n", server, msg);
2525           tprintf_close(tpr);
2526           return (0);
2527 }
2528 
2529 #ifndef NFS_NOSERVER
2530 
2531 /*
2532  * Socket upcall routine for nfsd sockets.  This runs in the protocol
2533  * thread and passes waitflag == M_NOWAIT.
2534  */
2535 void
nfsrv_rcv_upcall(struct socket * so,void * arg,int waitflag)2536 nfsrv_rcv_upcall(struct socket *so, void *arg, int waitflag)
2537 {
2538           struct nfssvc_sock *slp = (struct nfssvc_sock *)arg;
2539 
2540           if (slp->ns_needq_upcall == 0) {
2541                     slp->ns_needq_upcall = 1;     /* ok to race */
2542                     lwkt_gettoken(&nfs_token);
2543                     nfsrv_wakenfsd(slp, 1);
2544                     lwkt_reltoken(&nfs_token);
2545           }
2546 #if 0
2547           lwkt_gettoken(&slp->ns_token);
2548           slp->ns_flag |= SLP_NEEDQ;
2549           nfsrv_rcv(so, arg, waitflag);
2550           lwkt_reltoken(&slp->ns_token);
2551 #endif
2552 }
2553 
2554 /*
2555  * Process new data on a receive socket.  Essentially do as much as we can
2556  * non-blocking, else punt and it will be called with M_WAITOK from an nfsd.
2557  *
2558  * slp->ns_token is held on call
2559  */
2560 void
nfsrv_rcv(struct socket * so,void * arg,int waitflag)2561 nfsrv_rcv(struct socket *so, void *arg, int waitflag)
2562 {
2563           struct nfssvc_sock *slp = (struct nfssvc_sock *)arg;
2564           struct mbuf *m;
2565           struct sockaddr *nam;
2566           struct sockbuf sio;
2567           int flags, error;
2568           int nparallel_wakeup = 0;
2569 
2570           ASSERT_LWKT_TOKEN_HELD(&slp->ns_token);
2571 
2572           if ((slp->ns_flag & SLP_VALID) == 0)
2573                     return;
2574 
2575           /*
2576            * Do not allow an infinite number of completed RPC records to build
2577            * up before we stop reading data from the socket.  Otherwise we could
2578            * end up holding onto an unreasonable number of mbufs for requests
2579            * waiting for service.
2580            *
2581            * This should give pretty good feedback to the TCP layer and
2582            * prevents a memory crunch for other protocols.
2583            *
2584            * Note that the same service socket can be dispatched to several
2585            * nfs servers simultaniously.  The tcp protocol callback calls us
2586            * with M_NOWAIT.  nfsd calls us with M_WAITOK (typically).
2587            */
2588           if (NFSRV_RECLIMIT(slp))
2589                     return;
2590 
2591           /*
2592            * Handle protocol specifics to parse an RPC request.  We always
2593            * pull from the socket using non-blocking I/O.
2594            */
2595           if (so->so_type == SOCK_STREAM) {
2596                     /*
2597                      * The data has to be read in an orderly fashion from a TCP
2598                      * stream, unlike a UDP socket.  It is possible for soreceive
2599                      * and/or nfsrv_getstream() to block, so make sure only one
2600                      * entity is messing around with the TCP stream at any given
2601                      * moment.  The receive sockbuf's lock in soreceive is not
2602                      * sufficient.
2603                      */
2604                     if (slp->ns_flag & SLP_GETSTREAM)
2605                               return;
2606                     slp->ns_flag |= SLP_GETSTREAM;
2607 
2608                     /*
2609                      * Do soreceive().  Pull out as much data as possible without
2610                      * blocking.
2611                      */
2612                     sbinit(&sio, 1000000000);
2613                     flags = MSG_DONTWAIT;
2614                     error = so_pru_soreceive(so, NULL, NULL, &sio, NULL, &flags);
2615                     if (error || sio.sb_mb == NULL) {
2616                               if (error != EWOULDBLOCK)
2617                                         slp->ns_flag |= SLP_DISCONN;
2618                               slp->ns_flag &= ~(SLP_GETSTREAM | SLP_NEEDQ);
2619                               goto done;
2620                     }
2621                     m = sio.sb_mb;
2622                     if (slp->ns_rawend) {
2623                               slp->ns_rawend->m_next = m;
2624                               slp->ns_cc += sio.sb_cc;
2625                     } else {
2626                               slp->ns_raw = m;
2627                               slp->ns_cc = sio.sb_cc;
2628                     }
2629                     while (m->m_next)
2630                               m = m->m_next;
2631                     slp->ns_rawend = m;
2632 
2633                     /*
2634                      * Now try and parse as many record(s) as we can out of the
2635                      * raw stream data.  This will set SLP_DOREC.
2636                      */
2637                     error = nfsrv_getstream(slp, waitflag, &nparallel_wakeup);
2638                     if (error && error != EWOULDBLOCK)
2639                               slp->ns_flag |= SLP_DISCONN;
2640                     slp->ns_flag &= ~SLP_GETSTREAM;
2641           } else {
2642                     /*
2643                      * For UDP soreceive typically pulls just one packet, loop
2644                      * to get the whole batch.
2645                      */
2646                     do {
2647                               sbinit(&sio, 1000000000);
2648                               flags = MSG_DONTWAIT;
2649                               error = so_pru_soreceive(so, &nam, NULL, &sio,
2650                                                              NULL, &flags);
2651                               if (sio.sb_mb) {
2652                                         struct nfsrv_rec *rec;
2653                                         int mf = (waitflag & M_NOWAIT) ?
2654                                                       M_NOWAIT : M_WAITOK;
2655                                         rec = kmalloc(sizeof(struct nfsrv_rec),
2656                                                        M_NFSRVDESC, mf);
2657                                         if (!rec) {
2658                                                   if (nam)
2659                                                             kfree(nam, M_SONAME);
2660                                                   m_freem(sio.sb_mb);
2661                                                   continue;
2662                                         }
2663                                         nfs_realign(&sio.sb_mb, 10 * NFSX_UNSIGNED);
2664                                         rec->nr_address = nam;
2665                                         rec->nr_packet = sio.sb_mb;
2666                                         STAILQ_INSERT_TAIL(&slp->ns_rec, rec, nr_link);
2667                                         ++slp->ns_numrec;
2668                                         slp->ns_flag |= SLP_DOREC;
2669                                         ++nparallel_wakeup;
2670                               } else {
2671                                         slp->ns_flag &= ~SLP_NEEDQ;
2672                               }
2673                               if (error) {
2674                                         if ((so->so_proto->pr_flags & PR_CONNREQUIRED)
2675                                             && error != EWOULDBLOCK) {
2676                                                   slp->ns_flag |= SLP_DISCONN;
2677                                                   break;
2678                                         }
2679                               }
2680                               if (NFSRV_RECLIMIT(slp))
2681                                         break;
2682                     } while (sio.sb_mb);
2683           }
2684 
2685           /*
2686            * If we were upcalled from the tcp protocol layer and we have
2687            * fully parsed records ready to go, or there is new data pending,
2688            * or something went wrong, try to wake up a nfsd thread to deal
2689            * with it.
2690            */
2691 done:
2692           /* XXX this code is currently not executed (nfsrv_rcv_upcall) */
2693           if (waitflag == M_NOWAIT && (slp->ns_flag & SLP_ACTION_MASK)) {
2694                     lwkt_gettoken(&nfs_token);
2695                     nfsrv_wakenfsd(slp, nparallel_wakeup);
2696                     lwkt_reltoken(&nfs_token);
2697           }
2698 }
2699 
2700 /*
2701  * Try and extract an RPC request from the mbuf data list received on a
2702  * stream socket. The "waitflag" argument indicates whether or not it
2703  * can sleep.
2704  */
2705 static int
nfsrv_getstream(struct nfssvc_sock * slp,int waitflag,int * countp)2706 nfsrv_getstream(struct nfssvc_sock *slp, int waitflag, int *countp)
2707 {
2708           struct mbuf *m, **mpp;
2709           char *cp1, *cp2;
2710           int len;
2711           struct mbuf *om, *m2, *recm;
2712           u_int32_t recmark;
2713 
2714           for (;;) {
2715               if (slp->ns_reclen == 0) {
2716                     if (slp->ns_cc < NFSX_UNSIGNED)
2717                               return (0);
2718                     m = slp->ns_raw;
2719                     if (m->m_len >= NFSX_UNSIGNED) {
2720                               bcopy(mtod(m, caddr_t), (caddr_t)&recmark, NFSX_UNSIGNED);
2721                               m->m_data += NFSX_UNSIGNED;
2722                               m->m_len -= NFSX_UNSIGNED;
2723                     } else {
2724                               cp1 = (caddr_t)&recmark;
2725                               cp2 = mtod(m, caddr_t);
2726                               while (cp1 < ((caddr_t)&recmark) + NFSX_UNSIGNED) {
2727                                         while (m->m_len == 0) {
2728                                                   m = m->m_next;
2729                                                   cp2 = mtod(m, caddr_t);
2730                                         }
2731                                         *cp1++ = *cp2++;
2732                                         m->m_data++;
2733                                         m->m_len--;
2734                               }
2735                     }
2736                     slp->ns_cc -= NFSX_UNSIGNED;
2737                     recmark = ntohl(recmark);
2738                     slp->ns_reclen = recmark & ~0x80000000;
2739                     if (recmark & 0x80000000)
2740                               slp->ns_flag |= SLP_LASTFRAG;
2741                     else
2742                               slp->ns_flag &= ~SLP_LASTFRAG;
2743                     if (slp->ns_reclen > NFS_MAXPACKET || slp->ns_reclen <= 0) {
2744                               log(LOG_ERR, "%s (%d) from nfs client\n",
2745                                   "impossible packet length",
2746                                   slp->ns_reclen);
2747                               return (EPERM);
2748                     }
2749               }
2750 
2751               /*
2752                * Now get the record part.
2753                *
2754                * Note that slp->ns_reclen may be 0.  Linux sometimes
2755                * generates 0-length RPCs
2756                */
2757               recm = NULL;
2758               if (slp->ns_cc == slp->ns_reclen) {
2759                     recm = slp->ns_raw;
2760                     slp->ns_raw = slp->ns_rawend = NULL;
2761                     slp->ns_cc = slp->ns_reclen = 0;
2762               } else if (slp->ns_cc > slp->ns_reclen) {
2763                     len = 0;
2764                     m = slp->ns_raw;
2765                     om = NULL;
2766 
2767                     while (len < slp->ns_reclen) {
2768                               if ((len + m->m_len) > slp->ns_reclen) {
2769                                         m2 = m_copym(m, 0, slp->ns_reclen - len,
2770                                                   waitflag);
2771                                         if (m2) {
2772                                                   if (om) {
2773                                                             om->m_next = m2;
2774                                                             recm = slp->ns_raw;
2775                                                   } else
2776                                                             recm = m2;
2777                                                   m->m_data += slp->ns_reclen - len;
2778                                                   m->m_len -= slp->ns_reclen - len;
2779                                                   len = slp->ns_reclen;
2780                                         } else {
2781                                                   return (EWOULDBLOCK);
2782                                         }
2783                               } else if ((len + m->m_len) == slp->ns_reclen) {
2784                                         om = m;
2785                                         len += m->m_len;
2786                                         m = m->m_next;
2787                                         recm = slp->ns_raw;
2788                                         om->m_next = NULL;
2789                               } else {
2790                                         om = m;
2791                                         len += m->m_len;
2792                                         m = m->m_next;
2793                               }
2794                     }
2795                     slp->ns_raw = m;
2796                     slp->ns_cc -= len;
2797                     slp->ns_reclen = 0;
2798               } else {
2799                     return (0);
2800               }
2801 
2802               /*
2803                * Accumulate the fragments into a record.
2804                */
2805               mpp = &slp->ns_frag;
2806               while (*mpp)
2807                     mpp = &((*mpp)->m_next);
2808               *mpp = recm;
2809               if (slp->ns_flag & SLP_LASTFRAG) {
2810                     struct nfsrv_rec *rec;
2811                     int mf = (waitflag & M_NOWAIT) ? M_NOWAIT : M_WAITOK;
2812                     rec = kmalloc(sizeof(struct nfsrv_rec), M_NFSRVDESC, mf);
2813                     if (!rec) {
2814                         m_freem(slp->ns_frag);
2815                     } else {
2816                         nfs_realign(&slp->ns_frag, 10 * NFSX_UNSIGNED);
2817                         rec->nr_address = NULL;
2818                         rec->nr_packet = slp->ns_frag;
2819                         STAILQ_INSERT_TAIL(&slp->ns_rec, rec, nr_link);
2820                         ++slp->ns_numrec;
2821                         slp->ns_flag |= SLP_DOREC;
2822                         ++*countp;
2823                     }
2824                     slp->ns_frag = NULL;
2825               }
2826           }
2827 }
2828 
2829 #ifdef INVARIANTS
2830 
2831 /*
2832  * Sanity check our mbuf chain.
2833  */
2834 static void
nfs_checkpkt(struct mbuf * m,int len)2835 nfs_checkpkt(struct mbuf *m, int len)
2836 {
2837           int xlen = 0;
2838           while (m) {
2839                     xlen += m->m_len;
2840                     m = m->m_next;
2841           }
2842           if (xlen != len) {
2843                     panic("nfs_checkpkt: len mismatch %d/%d mbuf %p",
2844                               xlen, len, m);
2845           }
2846 }
2847 
2848 #else
2849 
2850 static void
nfs_checkpkt(struct mbuf * m __unused,int len __unused)2851 nfs_checkpkt(struct mbuf *m __unused, int len __unused)
2852 {
2853 }
2854 
2855 #endif
2856 
2857 /*
2858  * Parse an RPC header.
2859  *
2860  * If the socket is invalid or no records are pending we return ENOBUFS.
2861  * The caller must deal with NEEDQ races.
2862  */
2863 int
nfsrv_dorec(struct nfssvc_sock * slp,struct nfsd * nfsd,struct nfsrv_descript ** ndp)2864 nfsrv_dorec(struct nfssvc_sock *slp, struct nfsd *nfsd,
2865               struct nfsrv_descript **ndp)
2866 {
2867           struct nfsrv_rec *rec;
2868           struct mbuf *m;
2869           struct sockaddr *nam;
2870           struct nfsrv_descript *nd;
2871           int error;
2872 
2873           *ndp = NULL;
2874           if ((slp->ns_flag & SLP_VALID) == 0 || !STAILQ_FIRST(&slp->ns_rec))
2875                     return (ENOBUFS);
2876           rec = STAILQ_FIRST(&slp->ns_rec);
2877           STAILQ_REMOVE_HEAD(&slp->ns_rec, nr_link);
2878           KKASSERT(slp->ns_numrec > 0);
2879           if (--slp->ns_numrec == 0)
2880                     slp->ns_flag &= ~SLP_DOREC;
2881           nam = rec->nr_address;
2882           m = rec->nr_packet;
2883           kfree(rec, M_NFSRVDESC);
2884           nd = kmalloc(sizeof(struct nfsrv_descript), M_NFSRVDESC, M_WAITOK);
2885           nd->nd_md = nd->nd_mrep = m;
2886           nd->nd_nam2 = nam;
2887           nd->nd_dpos = mtod(m, caddr_t);
2888           error = nfs_getreq(nd, nfsd, TRUE);
2889           if (error) {
2890                     if (nam) {
2891                               kfree(nam, M_SONAME);
2892                     }
2893                     kfree((caddr_t)nd, M_NFSRVDESC);
2894                     return (error);
2895           }
2896           *ndp = nd;
2897           nfsd->nfsd_nd = nd;
2898           return (0);
2899 }
2900 
2901 /*
2902  * Try to assign service sockets to nfsd threads based on the number
2903  * of new rpc requests that have been queued on the service socket.
2904  *
2905  * If no nfsd's are available or additonal requests are pending, set the
2906  * NFSD_CHECKSLP flag so that one of the running nfsds will go look for
2907  * the work in the nfssvc_sock list when it is finished processing its
2908  * current work.  This flag is only cleared when an nfsd can not find
2909  * any new work to perform.
2910  */
2911 void
nfsrv_wakenfsd(struct nfssvc_sock * slp,int nparallel)2912 nfsrv_wakenfsd(struct nfssvc_sock *slp, int nparallel)
2913 {
2914           struct nfsd *nd;
2915 
2916           if ((slp->ns_flag & SLP_VALID) == 0)
2917                     return;
2918           if (nparallel <= 1)
2919                     nparallel = 1;
2920           TAILQ_FOREACH(nd, &nfsd_head, nfsd_chain) {
2921                     if (nd->nfsd_flag & NFSD_WAITING) {
2922                               nd->nfsd_flag &= ~NFSD_WAITING;
2923                               if (nd->nfsd_slp)
2924                                         panic("nfsd wakeup");
2925                               nfsrv_slpref(slp);
2926                               nd->nfsd_slp = slp;
2927                               wakeup((caddr_t)nd);
2928                               if (--nparallel == 0)
2929                                         break;
2930                     }
2931           }
2932 
2933           /*
2934            * If we couldn't assign slp then the NFSDs are all busy and
2935            * we set a flag indicating that there is pending work.
2936            */
2937           if (nparallel)
2938                     nfsd_head_flag |= NFSD_CHECKSLP;
2939 }
2940 #endif /* NFS_NOSERVER */
2941