1 /*        $NetBSD: nfs_syscalls.c,v 1.164 2024/07/05 04:31:54 rin Exp $         */
2 
3 /*
4  * Copyright (c) 1989, 1993
5  *        The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Rick Macklem at The University of Guelph.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *        @(#)nfs_syscalls.c  8.5 (Berkeley) 3/30/95
35  */
36 
37 #include <sys/cdefs.h>
38 __KERNEL_RCSID(0, "$NetBSD: nfs_syscalls.c,v 1.164 2024/07/05 04:31:54 rin Exp $");
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/file.h>
44 #include <sys/stat.h>
45 #include <sys/vnode.h>
46 #include <sys/mount.h>
47 #include <sys/proc.h>
48 #include <sys/uio.h>
49 #include <sys/malloc.h>
50 #include <sys/kmem.h>
51 #include <sys/buf.h>
52 #include <sys/mbuf.h>
53 #include <sys/socket.h>
54 #include <sys/socketvar.h>
55 #include <sys/signalvar.h>
56 #include <sys/domain.h>
57 #include <sys/protosw.h>
58 #include <sys/namei.h>
59 #include <sys/syslog.h>
60 #include <sys/filedesc.h>
61 #include <sys/kthread.h>
62 #include <sys/kauth.h>
63 #include <sys/syscallargs.h>
64 #include <sys/cprng.h>
65 #include <sys/rbtree.h>
66 
67 #include <netinet/in.h>
68 #include <netinet/tcp.h>
69 #include <nfs/xdr_subs.h>
70 #include <nfs/rpcv2.h>
71 #include <nfs/nfsproto.h>
72 #include <nfs/nfs.h>
73 #include <nfs/nfsm_subs.h>
74 #include <nfs/nfsrvcache.h>
75 #include <nfs/nfsmount.h>
76 #include <nfs/nfsnode.h>
77 #include <nfs/nfsrtt.h>
78 #include <nfs/nfs_var.h>
79 
80 extern int32_t (*nfsrv3_procs[NFS_NPROCS])(struct nfsrv_descript *,
81                                                             struct nfssvc_sock *,
82                                                             struct lwp *, struct mbuf **);
83 extern int nfsrvw_procrastinate;
84 extern int nuidhash_max;
85 
86 static int nfs_numnfsd = 0;
87 static struct nfsdrt nfsdrt;
88 kmutex_t nfsd_lock;
89 struct nfssvc_sockhead nfssvc_sockhead;
90 kcondvar_t nfsd_initcv;
91 struct nfssvc_sockhead nfssvc_sockpending;
92 struct nfsdidlehead nfsd_idle_head;
93 
94 static rb_tree_t nfsd_tree;
95 static const rb_tree_ops_t nfsd_tree_ops;
96 
97 int nfssvc_sockhead_flag;
98 int nfsd_head_flag;
99 
100 struct nfssvc_sock *nfs_udpsock;
101 struct nfssvc_sock *nfs_udp6sock;
102 
103 static struct nfssvc_sock *nfsrv_sockalloc(void);
104 static void nfsrv_sockfree(struct nfssvc_sock *);
105 static void nfsd_rt(int, struct nfsrv_descript *, int);
106 static int nfssvc_nfsd(struct nfssvc_copy_ops *, struct nfsd_srvargs *, void *,
107                     struct lwp *);
108 
109 static int nfsd_compare_nodes(void *, const void *, const void *);
110 static int nfsd_compare_key(void *, const void *, const void *);
111 
112 static struct nfsd *nfsd_bake_cookie(struct nfsd *);
113 static void nfsd_toss_cookie(struct nfsd *);
114 static struct nfsd *nfsd_get(struct nfsd *);
115 
116 static int nfssvc_addsock_in(struct nfsd_args *, const void *);
117 static int nfssvc_setexports_in(struct mountd_exports_list *, const void *);
118 static int nfssvc_nsd_in(struct nfsd_srvargs *, const void *);
119 static int nfssvc_nsd_out(void *, const struct nfsd_srvargs *);
120 static int nfssvc_exp_in(struct export_args *, const void *, size_t);
121 
122 static const rb_tree_ops_t nfsd_tree_ops = {
123           .rbto_compare_nodes = nfsd_compare_nodes,
124           .rbto_compare_key = nfsd_compare_key,
125           .rbto_node_offset = offsetof(struct nfsd, nfsd_node),
126 };
127 
128 static int
nfsd_compare_nodes(void * cookie,const void * va,const void * vb)129 nfsd_compare_nodes(void *cookie, const void *va, const void *vb)
130 {
131           const struct nfsd *na = va;
132           const struct nfsd *nb = vb;
133 
134           if (na->nfsd_cookie < nb->nfsd_cookie)
135                     return -1;
136           if (na->nfsd_cookie > nb->nfsd_cookie)
137                     return +1;
138           return 0;
139 }
140 
141 static int
nfsd_compare_key(void * cookie,const void * vn,const void * vk)142 nfsd_compare_key(void *cookie, const void *vn, const void *vk)
143 {
144           const struct nfsd *n = vn;
145           const uint32_t *k = vk;
146 
147           if (n->nfsd_cookie < *k)
148                     return -1;
149           if (n->nfsd_cookie > *k)
150                     return +1;
151           return 0;
152 }
153 
154 /*
155  * nfsd_bake_cookie(nfsd)
156  *
157  *        Bake a cookie for nfsd, hang it on the tree of nfsds, and
158  *        return a userland-safe pointer nfsdu neatly packed for
159  *        transport in struct nfsd_srvargs::nsd_nfsd.
160  */
161 static struct nfsd *
nfsd_bake_cookie(struct nfsd * nfsd)162 nfsd_bake_cookie(struct nfsd *nfsd)
163 {
164 
165           KASSERT(mutex_owned(&nfsd_lock));
166 
167           do {
168                     nfsd->nfsd_cookie = cprng_fast32();
169           } while (nfsd->nfsd_cookie == 0 ||
170               rb_tree_insert_node(&nfsd_tree, nfsd) != nfsd);
171 
172           return (struct nfsd *)(uintptr_t)nfsd->nfsd_cookie;
173 }
174 
175 /*
176  * nfsd_toss_cookie(nfsd)
177  *
178  *        Toss nfsd's cookie.
179  */
180 static void
nfsd_toss_cookie(struct nfsd * nfsd)181 nfsd_toss_cookie(struct nfsd *nfsd)
182 {
183 
184           KASSERT(mutex_owned(&nfsd_lock));
185           KASSERT(nfsd->nfsd_cookie != 0);
186 
187           rb_tree_remove_node(&nfsd_tree, nfsd);
188           nfsd->nfsd_cookie = 0;        /* paranoia */
189 }
190 
191 /*
192  * nfsd_get(nfsdu)
193  *
194  *        Return the struct nfsd pointer for the userland nfsdu cookie,
195  *        as stored in struct nfsd_srvargs::nsd_nfsd, or NULL if nfsdu is
196  *        not a current valid nfsd cookie.
197  *
198  *        Caller MUST NOT hold nfsd_lock.  Caller MUST NOT pass (struct
199  *        nfsd *)(uintptr_t)0, which is the sentinel value for no nfsd
200  *        cookie, for which the caller should check first.
201  */
202 static struct nfsd *
nfsd_get(struct nfsd * nfsdu)203 nfsd_get(struct nfsd *nfsdu)
204 {
205           uintptr_t cookie = (uintptr_t)nfsdu;
206           uint32_t key;
207           struct nfsd *nfsd;
208 
209           KASSERT(cookie != 0);
210           if (cookie > UINT32_MAX)
211                     return NULL;
212           key = cookie;
213 
214           mutex_enter(&nfsd_lock);
215           nfsd = rb_tree_find_node(&nfsd_tree, &key);
216           mutex_exit(&nfsd_lock);
217 
218           return nfsd;
219 }
220 
221 static int
nfssvc_addsock_in(struct nfsd_args * nfsdarg,const void * argp)222 nfssvc_addsock_in(struct nfsd_args *nfsdarg, const void *argp)
223 {
224 
225           return copyin(argp, nfsdarg, sizeof *nfsdarg);
226 }
227 
228 static int
nfssvc_setexports_in(struct mountd_exports_list * mel,const void * argp)229 nfssvc_setexports_in(struct mountd_exports_list *mel, const void *argp)
230 {
231 
232           return copyin(argp, mel, sizeof *mel);
233 }
234 
235 static int
nfssvc_nsd_in(struct nfsd_srvargs * nsd,const void * argp)236 nfssvc_nsd_in(struct nfsd_srvargs *nsd, const void *argp)
237 {
238 
239           return copyin(argp, nsd, sizeof *nsd);
240 }
241 
242 static int
nfssvc_nsd_out(void * argp,const struct nfsd_srvargs * nsd)243 nfssvc_nsd_out(void *argp, const struct nfsd_srvargs *nsd)
244 {
245 
246           return copyout(nsd, argp, sizeof *nsd);
247 }
248 
249 static int
nfssvc_exp_in(struct export_args * exp,const void * argp,size_t nexports)250 nfssvc_exp_in(struct export_args *exp, const void *argp, size_t nexports)
251 {
252 
253           return copyin(argp, exp, sizeof(*exp) * nexports);
254 }
255 
256 /*
257  * NFS server system calls
258  */
259 
260 static struct nfssvc_copy_ops native_ops = {
261           .addsock_in = nfssvc_addsock_in,
262           .setexports_in = nfssvc_setexports_in,
263           .nsd_in = nfssvc_nsd_in,
264           .nsd_out = nfssvc_nsd_out,
265           .exp_in = nfssvc_exp_in,
266 };
267 
268 /*
269  * Nfs server pseudo system call for the nfsd's
270  * Based on the flag value it either:
271  * - adds a socket to the selection list
272  * - remains in the kernel as an nfsd
273  * - remains in the kernel as an nfsiod
274  */
275 
276 int
sys_nfssvc(struct lwp * l,const struct sys_nfssvc_args * uap,register_t * retval)277 sys_nfssvc(struct lwp *l, const struct sys_nfssvc_args *uap, register_t *retval)
278 {
279           /* {
280                     syscallarg(int) flag;
281                     syscallarg(void *) argp;
282           } */
283           int       flag = SCARG(uap, flag);
284           void      *argp = SCARG(uap, argp);
285 
286           return do_nfssvc(&native_ops, l, flag, argp, retval);
287 }
288 
289 int
do_nfssvc(struct nfssvc_copy_ops * ops,struct lwp * l,int flag,void * argp,register_t * retval)290 do_nfssvc(struct nfssvc_copy_ops *ops, struct lwp *l, int flag, void *argp, register_t *retval)
291 {
292           int error;
293           file_t *fp;
294           struct mbuf *nam;
295           struct nfsd_args nfsdarg;
296           struct nfsd_srvargs nfsd_srvargs, *nsd = &nfsd_srvargs;
297           struct nfsd *nfsd = NULL;
298           struct nfssvc_sock *slp;
299           struct nfsuid *nuidp;
300 
301           error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_NFS,
302               KAUTH_REQ_NETWORK_NFS_SVC, NULL, NULL, NULL);
303           if (error)
304                     return (error);
305 
306           mutex_enter(&nfsd_lock);
307           while (nfssvc_sockhead_flag & SLP_INIT) {
308                     cv_wait(&nfsd_initcv, &nfsd_lock);
309           }
310           mutex_exit(&nfsd_lock);
311 
312           if (flag & NFSSVC_BIOD) {
313                     /* Dummy implementation of nfsios for 1.4 and earlier. */
314                     error = kpause("nfsbiod", true, 0, NULL);
315           } else if (flag & NFSSVC_MNTD) {
316                     error = ENOSYS;
317           } else if (flag & NFSSVC_ADDSOCK) {
318                     error = ops->addsock_in(&nfsdarg, argp);
319                     if (error)
320                               return (error);
321                     /* getsock() will use the descriptor for us */
322                     if ((fp = fd_getfile(nfsdarg.sock)) == NULL)
323                               return (EBADF);
324                     if (fp->f_type != DTYPE_SOCKET) {
325                               fd_putfile(nfsdarg.sock);
326                               return (ENOTSOCK);
327                     }
328                     /*
329                      * Get the client address for connected sockets.
330                      */
331                     if (nfsdarg.name == NULL || nfsdarg.namelen == 0)
332                               nam = (struct mbuf *)0;
333                     else {
334                               error = sockargs(&nam, nfsdarg.name, nfsdarg.namelen,
335                                         UIO_USERSPACE, MT_SONAME);
336                               if (error) {
337                                         fd_putfile(nfsdarg.sock);
338                                         return (error);
339                               }
340                     }
341                     error = nfssvc_addsock(fp, nam);
342                     fd_putfile(nfsdarg.sock);
343           } else if (flag & (NFSSVC_SETEXPORTSLIST | NFSSVC_REPLACEEXPORTSLIST)) {
344                     struct export_args *args;
345                     struct mountd_exports_list mel;
346 
347                     error = ops->setexports_in(&mel, argp);
348                     if (error != 0)
349                               return error;
350 
351                     args = (struct export_args *)malloc(mel.mel_nexports *
352                         sizeof(struct export_args), M_TEMP, M_WAITOK);
353                     error = ops->exp_in(args, mel.mel_exports, mel.mel_nexports);
354                     if (error != 0) {
355                               free(args, M_TEMP);
356                               return error;
357                     }
358                     mel.mel_exports = args;
359 
360                     error = mountd_set_exports_list(&mel, l, NULL,
361                         flag & (NFSSVC_SETEXPORTSLIST | NFSSVC_REPLACEEXPORTSLIST));
362 
363                     free(args, M_TEMP);
364           } else {
365                     error = ops->nsd_in(nsd, argp);
366                     if (error)
367                               return (error);
368                     if ((uintptr_t)nsd->nsd_nfsd != 0 &&
369                         (nfsd = nfsd_get(nsd->nsd_nfsd)) == NULL)
370                               return (EINVAL);
371                     if ((flag & NFSSVC_AUTHIN) &&
372                         nfsd != NULL &&
373                         (nfsd->nfsd_slp->ns_flags & SLP_VALID)) {
374                               slp = nfsd->nfsd_slp;
375 
376                               /*
377                                * First check to see if another nfsd has already
378                                * added this credential.
379                                */
380                               LIST_FOREACH(nuidp, NUIDHASH(slp, nsd->nsd_cr.cr_uid),
381                                   nu_hash) {
382                                         if (kauth_cred_geteuid(nuidp->nu_cr) ==
383                                             nsd->nsd_cr.cr_uid &&
384                                             (!nfsd->nfsd_nd->nd_nam2 ||
385                                              netaddr_match(NU_NETFAM(nuidp),
386                                              &nuidp->nu_haddr, nfsd->nfsd_nd->nd_nam2)))
387                                                   break;
388                               }
389                               if (nuidp) {
390                                   kauth_cred_hold(nuidp->nu_cr);
391                                   nfsd->nfsd_nd->nd_cr = nuidp->nu_cr;
392                                   nfsd->nfsd_nd->nd_flag |= ND_KERBFULL;
393                               } else {
394                                   /*
395                                    * Nope, so we will.
396                                    */
397                                   if (slp->ns_numuids < nuidhash_max) {
398                                         slp->ns_numuids++;
399                                         nuidp = kmem_alloc(sizeof(*nuidp), KM_SLEEP);
400                                   } else
401                                         nuidp = (struct nfsuid *)0;
402                                   if ((slp->ns_flags & SLP_VALID) == 0) {
403                                         if (nuidp)
404                                             kmem_free(nuidp, sizeof(*nuidp));
405                                   } else {
406                                         if (nuidp == (struct nfsuid *)0) {
407                                             nuidp = TAILQ_FIRST(&slp->ns_uidlruhead);
408                                             LIST_REMOVE(nuidp, nu_hash);
409                                             TAILQ_REMOVE(&slp->ns_uidlruhead, nuidp,
410                                                   nu_lru);
411                                             if (nuidp->nu_flag & NU_NAM)
412                                                   m_freem(nuidp->nu_nam);
413                                       }
414                                         nuidp->nu_flag = 0;
415                                         kauth_uucred_to_cred(nuidp->nu_cr,
416                                             &nsd->nsd_cr);
417                                         nuidp->nu_timestamp = nsd->nsd_timestamp;
418                                         nuidp->nu_expire = time_second + nsd->nsd_ttl;
419                                         /*
420                                          * and save the session key in nu_key.
421                                          */
422                                         memcpy(nuidp->nu_key, nsd->nsd_key,
423                                             sizeof(nsd->nsd_key));
424                                         if (nfsd->nfsd_nd->nd_nam2) {
425                                             struct sockaddr_in *saddr;
426 
427                                             saddr = mtod(nfsd->nfsd_nd->nd_nam2,
428                                                    struct sockaddr_in *);
429                                             switch (saddr->sin_family) {
430                                             case AF_INET:
431                                                   nuidp->nu_flag |= NU_INETADDR;
432                                                   nuidp->nu_inetaddr =
433                                                        saddr->sin_addr.s_addr;
434                                                   break;
435                                             case AF_INET6:
436                                                   nuidp->nu_flag |= NU_NAM;
437                                                   nuidp->nu_nam = m_copym(
438                                                       nfsd->nfsd_nd->nd_nam2, 0,
439                                                        M_COPYALL, M_WAIT);
440                                                   break;
441                                             default:
442                                                   kmem_free(nuidp, sizeof(*nuidp));
443                                                   return EAFNOSUPPORT;
444                                             };
445                                         }
446                                         TAILQ_INSERT_TAIL(&slp->ns_uidlruhead, nuidp,
447                                                   nu_lru);
448                                         LIST_INSERT_HEAD(NUIDHASH(slp, nsd->nsd_uid),
449                                                   nuidp, nu_hash);
450                                         kauth_cred_hold(nuidp->nu_cr);
451                                         nfsd->nfsd_nd->nd_cr = nuidp->nu_cr;
452                                         nfsd->nfsd_nd->nd_flag |= ND_KERBFULL;
453                                   }
454                               }
455                     }
456                     if ((flag & NFSSVC_AUTHINFAIL) &&
457                         nfsd != NULL)
458                               nfsd->nfsd_flag |= NFSD_AUTHFAIL;
459                     error = nfssvc_nfsd(ops, nsd, argp, l);
460           }
461           if (error == EINTR || error == ERESTART)
462                     error = 0;
463           return (error);
464 }
465 
466 static struct nfssvc_sock *
nfsrv_sockalloc(void)467 nfsrv_sockalloc(void)
468 {
469           struct nfssvc_sock *slp;
470 
471           slp = kmem_alloc(sizeof(*slp), KM_SLEEP);
472           memset(slp, 0, sizeof (struct nfssvc_sock));
473           mutex_init(&slp->ns_lock, MUTEX_DRIVER, IPL_SOFTNET);
474           mutex_init(&slp->ns_alock, MUTEX_DRIVER, IPL_SOFTNET);
475           cv_init(&slp->ns_cv, "nfsdsock");
476           TAILQ_INIT(&slp->ns_uidlruhead);
477           LIST_INIT(&slp->ns_tq);
478           SIMPLEQ_INIT(&slp->ns_sendq);
479           mutex_enter(&nfsd_lock);
480           TAILQ_INSERT_TAIL(&nfssvc_sockhead, slp, ns_chain);
481           mutex_exit(&nfsd_lock);
482 
483           return slp;
484 }
485 
486 static void
nfsrv_sockfree(struct nfssvc_sock * slp)487 nfsrv_sockfree(struct nfssvc_sock *slp)
488 {
489 
490           KASSERT(slp->ns_so == NULL);
491           KASSERT(slp->ns_fp == NULL);
492           KASSERT((slp->ns_flags & SLP_VALID) == 0);
493           mutex_destroy(&slp->ns_lock);
494           mutex_destroy(&slp->ns_alock);
495           cv_destroy(&slp->ns_cv);
496           kmem_free(slp, sizeof(*slp));
497 }
498 
499 /*
500  * Adds a socket to the list for servicing by nfsds.
501  */
502 int
nfssvc_addsock(file_t * fp,struct mbuf * mynam)503 nfssvc_addsock(file_t *fp, struct mbuf *mynam)
504 {
505           int siz;
506           struct nfssvc_sock *slp;
507           struct socket *so;
508           struct nfssvc_sock *tslp;
509           int error;
510           int val;
511 
512           so = fp->f_socket;
513           tslp = (struct nfssvc_sock *)0;
514           /*
515            * Add it to the list, as required.
516            */
517           if (so->so_proto->pr_protocol == IPPROTO_UDP) {
518                     if (so->so_proto->pr_domain->dom_family == AF_INET6)
519                               tslp = nfs_udp6sock;
520                     else {
521                               tslp = nfs_udpsock;
522                               if (tslp->ns_flags & SLP_VALID) {
523                                         m_freem(mynam);
524                                         return (EPERM);
525                               }
526                     }
527           }
528           if (so->so_type == SOCK_STREAM)
529                     siz = NFS_MAXPACKET + sizeof (u_long);
530           else
531                     siz = NFS_MAXPACKET;
532           solock(so);
533           error = soreserve(so, siz, siz);
534           sounlock(so);
535           if (error) {
536                     m_freem(mynam);
537                     return (error);
538           }
539 
540           /*
541            * Set protocol specific options { for now TCP only } and
542            * reserve some space. For datagram sockets, this can get called
543            * repeatedly for the same socket, but that isn't harmful.
544            */
545           if (so->so_type == SOCK_STREAM) {
546                     val = 1;
547                     so_setsockopt(NULL, so, SOL_SOCKET, SO_KEEPALIVE, &val,
548                         sizeof(val));
549           }
550           if ((so->so_proto->pr_domain->dom_family == AF_INET ||
551               so->so_proto->pr_domain->dom_family == AF_INET6) &&
552               so->so_proto->pr_protocol == IPPROTO_TCP) {
553                     val = 1;
554                     so_setsockopt(NULL, so, IPPROTO_TCP, TCP_NODELAY, &val,
555                         sizeof(val));
556           }
557           solock(so);
558           so->so_rcv.sb_flags &= ~SB_NOINTR;
559           so->so_rcv.sb_timeo = 0;
560           so->so_snd.sb_flags &= ~SB_NOINTR;
561           so->so_snd.sb_timeo = 0;
562           sounlock(so);
563           if (tslp) {
564                     slp = tslp;
565           } else {
566                     slp = nfsrv_sockalloc();
567           }
568           slp->ns_so = so;
569           slp->ns_nam = mynam;
570           mutex_enter(&fp->f_lock);
571           fp->f_count++;
572           mutex_exit(&fp->f_lock);
573           slp->ns_fp = fp;
574           slp->ns_flags = SLP_VALID;
575           slp->ns_aflags = SLP_A_NEEDQ;
576           slp->ns_gflags = 0;
577           slp->ns_sflags = 0;
578           solock(so);
579           so->so_upcallarg = (void *)slp;
580           so->so_upcall = nfsrv_soupcall;
581           so->so_rcv.sb_flags |= SB_UPCALL;
582           sounlock(so);
583           nfsrv_wakenfsd(slp);
584           return (0);
585 }
586 
587 /*
588  * Called by nfssvc() for nfsds. Just loops around servicing rpc requests
589  * until it is killed by a signal.
590  */
591 static int
nfssvc_nfsd(struct nfssvc_copy_ops * ops,struct nfsd_srvargs * nsd,void * argp,struct lwp * l)592 nfssvc_nfsd(struct nfssvc_copy_ops *ops, struct nfsd_srvargs *nsd,
593               void *argp, struct lwp *l)
594 {
595           struct timeval tv;
596           struct mbuf *m;
597           struct nfssvc_sock *slp;
598           struct nfsd *nfsd;
599           struct nfsrv_descript *nd = NULL;
600           struct mbuf *mreq;
601           u_quad_t cur_usec;
602           int error = 0, cacherep, siz, sotype, writes_todo;
603           struct proc *p = l->l_proc;
604           bool doreinit;
605 
606 #ifndef nolint
607           cacherep = RC_DOIT;
608           writes_todo = 0;
609 #endif
610           /*
611            * If userland didn't provide an nfsd cookie, bake a fresh one;
612            * if they did provide one, look it up.
613            */
614           if ((uintptr_t)nsd->nsd_nfsd == 0) {
615                     nfsd = kmem_alloc(sizeof(*nfsd), KM_SLEEP);
616                     memset(nfsd, 0, sizeof (struct nfsd));
617                     cv_init(&nfsd->nfsd_cv, "nfsd");
618                     nfsd->nfsd_procp = p;
619                     mutex_enter(&nfsd_lock);
620                     while ((nfssvc_sockhead_flag & SLP_INIT) != 0) {
621                               KASSERT(nfs_numnfsd == 0);
622                               cv_wait(&nfsd_initcv, &nfsd_lock);
623                     }
624                     nsd->nsd_nfsd = nfsd_bake_cookie(nfsd);
625                     nfs_numnfsd++;
626                     mutex_exit(&nfsd_lock);
627           } else if ((nfsd = nfsd_get(nsd->nsd_nfsd)) == NULL) {
628                     return (EINVAL);
629           }
630           KASSERT(nfsd != NULL);
631           KASSERT(nsd->nsd_nfsd != (struct nfsd *)(uintptr_t)0);
632 
633           /*
634            * Loop getting rpc requests until SIGKILL.
635            */
636           for (;;) {
637                     bool dummy;
638 
639                     preempt_point();
640 
641                     if (nfsd->nfsd_slp == NULL) {
642                               mutex_enter(&nfsd_lock);
643                               while (nfsd->nfsd_slp == NULL &&
644                                   (nfsd_head_flag & NFSD_CHECKSLP) == 0) {
645                                         SLIST_INSERT_HEAD(&nfsd_idle_head, nfsd,
646                                             nfsd_idle);
647                                         error = cv_wait_sig(&nfsd->nfsd_cv, &nfsd_lock);
648                                         if (error) {
649                                                   slp = nfsd->nfsd_slp;
650                                                   nfsd->nfsd_slp = NULL;
651                                                   if (!slp)
652                                                             SLIST_REMOVE(&nfsd_idle_head,
653                                                                 nfsd, nfsd, nfsd_idle);
654                                                   mutex_exit(&nfsd_lock);
655                                                   if (slp) {
656                                                             nfsrv_wakenfsd(slp);
657                                                             nfsrv_slpderef(slp);
658                                                   }
659                                                   goto done;
660                                         }
661                               }
662                               if (nfsd->nfsd_slp == NULL &&
663                                   (nfsd_head_flag & NFSD_CHECKSLP) != 0) {
664                                         slp = TAILQ_FIRST(&nfssvc_sockpending);
665                                         if (slp) {
666                                                   KASSERT((slp->ns_gflags & SLP_G_DOREC)
667                                                       != 0);
668                                                   TAILQ_REMOVE(&nfssvc_sockpending, slp,
669                                                       ns_pending);
670                                                   slp->ns_gflags &= ~SLP_G_DOREC;
671                                                   slp->ns_sref++;
672                                                   nfsd->nfsd_slp = slp;
673                                         } else
674                                                   nfsd_head_flag &= ~NFSD_CHECKSLP;
675                               }
676                               KASSERT(nfsd->nfsd_slp == NULL ||
677                                   nfsd->nfsd_slp->ns_sref > 0);
678                               mutex_exit(&nfsd_lock);
679                               if ((slp = nfsd->nfsd_slp) == NULL)
680                                         continue;
681                               if (slp->ns_flags & SLP_VALID) {
682                                         bool more;
683 
684                                         if (nfsdsock_testbits(slp, SLP_A_NEEDQ)) {
685                                                   nfsrv_rcv(slp);
686                                         }
687                                         if (nfsdsock_testbits(slp, SLP_A_DISCONN)) {
688                                                   nfsrv_zapsock(slp);
689                                         }
690                                         error = nfsrv_dorec(slp, nfsd, &nd, &more);
691                                         getmicrotime(&tv);
692                                         cur_usec = (u_quad_t)tv.tv_sec * 1000000 +
693                                                   (u_quad_t)tv.tv_usec;
694                                         writes_todo = 0;
695                                         if (error) {
696                                                   struct nfsrv_descript *nd2;
697 
698                                                   mutex_enter(&nfsd_lock);
699                                                   nd2 = LIST_FIRST(&slp->ns_tq);
700                                                   if (nd2 != NULL &&
701                                                       nd2->nd_time <= cur_usec) {
702                                                             error = 0;
703                                                             cacherep = RC_DOIT;
704                                                             writes_todo = 1;
705                                                   }
706                                                   mutex_exit(&nfsd_lock);
707                                         }
708                                         if (error == 0 && more) {
709                                                   nfsrv_wakenfsd(slp);
710                                         }
711                               }
712                     } else {
713                               error = 0;
714                               slp = nfsd->nfsd_slp;
715                     }
716                     KASSERT(slp != NULL);
717                     KASSERT(nfsd->nfsd_slp == slp);
718                     if (error || (slp->ns_flags & SLP_VALID) == 0) {
719                               if (nd) {
720                                         nfsdreq_free(nd);
721                                         nd = NULL;
722                               }
723                               nfsd->nfsd_slp = NULL;
724                               nfsrv_slpderef(slp);
725                               continue;
726                     }
727                     sotype = slp->ns_so->so_type;
728                     if (nd) {
729                               getmicrotime(&nd->nd_starttime);
730                               if (nd->nd_nam2)
731                                         nd->nd_nam = nd->nd_nam2;
732                               else
733                                         nd->nd_nam = slp->ns_nam;
734 
735                               /*
736                                * Check to see if authorization is needed.
737                                */
738                               if (nfsd->nfsd_flag & NFSD_NEEDAUTH) {
739                                         nfsd->nfsd_flag &= ~NFSD_NEEDAUTH;
740                                         nsd->nsd_haddr = mtod(nd->nd_nam,
741                                             struct sockaddr_in *)->sin_addr.s_addr;
742                                         nsd->nsd_authlen = nfsd->nfsd_authlen;
743                                         nsd->nsd_verflen = nfsd->nfsd_verflen;
744                                         if (!copyout(nfsd->nfsd_authstr,
745                                             nsd->nsd_authstr, nfsd->nfsd_authlen) &&
746                                             !copyout(nfsd->nfsd_verfstr,
747                                             nsd->nsd_verfstr, nfsd->nfsd_verflen) &&
748                                             !ops->nsd_out(argp, nsd)) {
749                                                   return (ENEEDAUTH);
750                                         }
751                                         cacherep = RC_DROPIT;
752                               } else
753                                         cacherep = nfsrv_getcache(nd, slp, &mreq);
754 
755                               if (nfsd->nfsd_flag & NFSD_AUTHFAIL) {
756                                         nfsd->nfsd_flag &= ~NFSD_AUTHFAIL;
757                                         nd->nd_procnum = NFSPROC_NOOP;
758                                         nd->nd_repstat =
759                                             (NFSERR_AUTHERR | AUTH_TOOWEAK);
760                                         cacherep = RC_DOIT;
761                               }
762                     }
763 
764                     /*
765                      * Loop to get all the write rpc relies that have been
766                      * gathered together.
767                      */
768                     do {
769                               switch (cacherep) {
770                               case RC_DOIT:
771                                         mreq = NULL;
772                                         netexport_rdlock();
773                                         if (writes_todo || nd == NULL ||
774                                              (!(nd->nd_flag & ND_NFSV3) &&
775                                              nd->nd_procnum == NFSPROC_WRITE &&
776                                              nfsrvw_procrastinate > 0))
777                                                   error = nfsrv_writegather(&nd, slp,
778                                                       l, &mreq);
779                                         else
780                                                   error =
781                                                       (*(nfsrv3_procs[nd->nd_procnum]))
782                                                       (nd, slp, l, &mreq);
783                                         netexport_rdunlock();
784                                         if (mreq == NULL) {
785                                                   if (nd != NULL) {
786                                                             if (nd->nd_nam2)
787                                                                       m_free(nd->nd_nam2);
788                                                   }
789                                                   break;
790                                         }
791                                         if (error) {
792                                                   nfsstats.srv_errs++;
793                                                   if (nd) {
794                                                             nfsrv_updatecache(nd, false,
795                                                                 mreq);
796                                                             m_freem(nd->nd_nam2);
797                                                   }
798                                                   break;
799                                         }
800                                         if (nd) {
801                                                   nfsstats.srvrpccnt[nd->nd_procnum]++;
802                                                   nfsrv_updatecache(nd, true, mreq);
803                                                   nd->nd_mrep = NULL;
804                                         }
805                                         /* FALLTHROUGH */
806                               case RC_REPLY:
807                                         m = mreq;
808                                         siz = 0;
809                                         while (m) {
810                                                   siz += m->m_len;
811                                                   m = m->m_next;
812                                         }
813                                         if (siz <= 0 || siz > NFS_MAXPACKET) {
814                                                   printf("mbuf siz=%d\n",siz);
815                                                   panic("Bad nfs svc reply");
816                                         }
817                                         m = mreq;
818                                         m->m_pkthdr.len = siz;
819                                         m_reset_rcvif(m);
820                                         /*
821                                          * For stream protocols, prepend a Sun RPC
822                                          * Record Mark.
823                                          */
824                                         if (sotype == SOCK_STREAM) {
825                                                   M_PREPEND(m, NFSX_UNSIGNED, M_WAIT);
826                                                   *mtod(m, u_int32_t *) =
827                                                       htonl(0x80000000 | siz);
828                                         }
829                                         if (nd) {
830                                                   nd->nd_mreq = m;
831                                                   if (nfsrtton) {
832                                                             nfsd_rt(slp->ns_so->so_type, nd,
833                                                                 cacherep);
834                                                   }
835                                                   error = nfsdsock_sendreply(slp, nd);
836                                                   nd = NULL;
837                                         }
838                                         if (error == EPIPE)
839                                                   nfsrv_zapsock(slp);
840                                         if (error == EINTR || error == ERESTART) {
841                                                   nfsd->nfsd_slp = NULL;
842                                                   nfsrv_slpderef(slp);
843                                                   goto done;
844                                         }
845                                         break;
846                               case RC_DROPIT:
847                                         if (nd) {
848                                                   if (nfsrtton)
849                                                             nfsd_rt(sotype, nd, cacherep);
850                                                   m_freem(nd->nd_mrep);
851                                                   m_freem(nd->nd_nam2);
852                                         }
853                                         break;
854                               }
855                               if (nd) {
856                                         nfsdreq_free(nd);
857                                         nd = NULL;
858                               }
859 
860                               /*
861                                * Check to see if there are outstanding writes that
862                                * need to be serviced.
863                                */
864                               getmicrotime(&tv);
865                               cur_usec = (u_quad_t)tv.tv_sec * 1000000 +
866                                   (u_quad_t)tv.tv_usec;
867                               mutex_enter(&nfsd_lock);
868                               if (LIST_FIRST(&slp->ns_tq) &&
869                                   LIST_FIRST(&slp->ns_tq)->nd_time <= cur_usec) {
870                                         cacherep = RC_DOIT;
871                                         writes_todo = 1;
872                               } else
873                                         writes_todo = 0;
874                               mutex_exit(&nfsd_lock);
875                     } while (writes_todo);
876                     if (nfsrv_dorec(slp, nfsd, &nd, &dummy)) {
877                               nfsd->nfsd_slp = NULL;
878                               nfsrv_slpderef(slp);
879                     }
880           }
881 done:
882           mutex_enter(&nfsd_lock);
883           nfsd_toss_cookie(nfsd);
884           doreinit = --nfs_numnfsd == 0;
885           if (doreinit)
886                     nfssvc_sockhead_flag |= SLP_INIT;
887           mutex_exit(&nfsd_lock);
888           cv_destroy(&nfsd->nfsd_cv);
889           kmem_free(nfsd, sizeof(*nfsd));
890           KASSERT(nsd->nsd_nfsd != (struct nfsd *)(uintptr_t)0);
891           nsd->nsd_nfsd = (struct nfsd *)(uintptr_t)0;
892           if (doreinit)
893                     nfsrv_init(true);   /* Reinitialize everything */
894           return (error);
895 }
896 
897 /*
898  * Shut down a socket associated with an nfssvc_sock structure.
899  * Should be called with the send lock set, if required.
900  * The trick here is to increment the sref at the start, so that the nfsds
901  * will stop using it and clear ns_flag at the end so that it will not be
902  * reassigned during cleanup.
903  *
904  * called at splsoftnet.
905  */
906 void
nfsrv_zapsock(struct nfssvc_sock * slp)907 nfsrv_zapsock(struct nfssvc_sock *slp)
908 {
909           struct nfsuid *nuidp, *nnuidp;
910           struct nfsrv_descript *nwp;
911           struct socket *so;
912           struct mbuf *m;
913 
914           if (nfsdsock_drain(slp)) {
915                     return;
916           }
917           mutex_enter(&nfsd_lock);
918           if (slp->ns_gflags & SLP_G_DOREC) {
919                     TAILQ_REMOVE(&nfssvc_sockpending, slp, ns_pending);
920                     slp->ns_gflags &= ~SLP_G_DOREC;
921           }
922           mutex_exit(&nfsd_lock);
923 
924           so = slp->ns_so;
925           KASSERT(so != NULL);
926           solock(so);
927           so->so_upcall = NULL;
928           so->so_upcallarg = NULL;
929           so->so_rcv.sb_flags &= ~SB_UPCALL;
930           soshutdown(so, SHUT_RDWR);
931           sounlock(so);
932 
933           m_freem(slp->ns_raw);
934           m = slp->ns_rec;
935           while (m != NULL) {
936                     struct mbuf *n;
937 
938                     n = m->m_nextpkt;
939                     m_freem(m);
940                     m = n;
941           }
942           /* XXX what about freeing ns_frag ? */
943           for (nuidp = TAILQ_FIRST(&slp->ns_uidlruhead); nuidp != 0;
944               nuidp = nnuidp) {
945                     nnuidp = TAILQ_NEXT(nuidp, nu_lru);
946                     LIST_REMOVE(nuidp, nu_hash);
947                     TAILQ_REMOVE(&slp->ns_uidlruhead, nuidp, nu_lru);
948                     if (nuidp->nu_flag & NU_NAM)
949                               m_freem(nuidp->nu_nam);
950                     kmem_free(nuidp, sizeof(*nuidp));
951           }
952           mutex_enter(&nfsd_lock);
953           while ((nwp = LIST_FIRST(&slp->ns_tq)) != NULL) {
954                     LIST_REMOVE(nwp, nd_tq);
955                     mutex_exit(&nfsd_lock);
956                     nfsdreq_free(nwp);
957                     mutex_enter(&nfsd_lock);
958           }
959           mutex_exit(&nfsd_lock);
960 }
961 
962 /*
963  * Derefence a server socket structure. If it has no more references and
964  * is no longer valid, you can throw it away.
965  */
966 void
nfsrv_slpderef(struct nfssvc_sock * slp)967 nfsrv_slpderef(struct nfssvc_sock *slp)
968 {
969           uint32_t ref;
970 
971           mutex_enter(&nfsd_lock);
972           KASSERT(slp->ns_sref > 0);
973           ref = --slp->ns_sref;
974           if (ref == 0 && (slp->ns_flags & SLP_VALID) == 0) {
975                     file_t *fp;
976 
977                     KASSERT((slp->ns_gflags & SLP_G_DOREC) == 0);
978                     TAILQ_REMOVE(&nfssvc_sockhead, slp, ns_chain);
979                     mutex_exit(&nfsd_lock);
980 
981                     fp = slp->ns_fp;
982                     if (fp != NULL) {
983                               slp->ns_fp = NULL;
984                               KASSERT(fp != NULL);
985                               KASSERT(fp->f_socket == slp->ns_so);
986                               KASSERT(fp->f_count > 0);
987                               closef(fp);
988                               slp->ns_so = NULL;
989                     }
990 
991                     if (slp->ns_nam)
992                               m_free(slp->ns_nam);
993                     nfsrv_sockfree(slp);
994           } else
995                     mutex_exit(&nfsd_lock);
996 }
997 
998 /*
999  * Initialize the data structures for the server.
1000  * Handshake with any new nfsds starting up to avoid any chance of
1001  * corruption.
1002  */
1003 void
nfsrv_init(int terminating)1004 nfsrv_init(int terminating)
1005 {
1006           struct nfssvc_sock *slp;
1007 
1008           if (!terminating) {
1009                     mutex_init(&nfsd_lock, MUTEX_DRIVER, IPL_SOFTNET);
1010                     cv_init(&nfsd_initcv, "nfsdinit");
1011           }
1012 
1013           mutex_enter(&nfsd_lock);
1014           if (!terminating && (nfssvc_sockhead_flag & SLP_INIT) != 0)
1015                     panic("nfsd init");
1016           nfssvc_sockhead_flag |= SLP_INIT;
1017 
1018           if (terminating) {
1019                     KASSERT(SLIST_EMPTY(&nfsd_idle_head));
1020                     KASSERT(RB_TREE_MIN(&nfsd_tree) == NULL);
1021                     while ((slp = TAILQ_FIRST(&nfssvc_sockhead)) != NULL) {
1022                               mutex_exit(&nfsd_lock);
1023                               KASSERT(slp->ns_sref == 0);
1024                               slp->ns_sref++;
1025                               nfsrv_zapsock(slp);
1026                               nfsrv_slpderef(slp);
1027                               mutex_enter(&nfsd_lock);
1028                     }
1029                     KASSERT(TAILQ_EMPTY(&nfssvc_sockpending));
1030                     mutex_exit(&nfsd_lock);
1031                     nfsrv_cleancache(); /* And clear out server cache */
1032           } else {
1033                     mutex_exit(&nfsd_lock);
1034                     nfs_pub.np_valid = 0;
1035           }
1036 
1037           TAILQ_INIT(&nfssvc_sockhead);
1038           TAILQ_INIT(&nfssvc_sockpending);
1039 
1040           rb_tree_init(&nfsd_tree, &nfsd_tree_ops);
1041           SLIST_INIT(&nfsd_idle_head);
1042           nfsd_head_flag &= ~NFSD_CHECKSLP;
1043 
1044           nfs_udpsock = nfsrv_sockalloc();
1045           nfs_udp6sock = nfsrv_sockalloc();
1046 
1047           mutex_enter(&nfsd_lock);
1048           nfssvc_sockhead_flag &= ~SLP_INIT;
1049           cv_broadcast(&nfsd_initcv);
1050           mutex_exit(&nfsd_lock);
1051 }
1052 
1053 void
nfsrv_fini(void)1054 nfsrv_fini(void)
1055 {
1056 
1057           nfsrv_init(true);
1058           cv_destroy(&nfsd_initcv);
1059           mutex_destroy(&nfsd_lock);
1060 }
1061 
1062 /*
1063  * Add entries to the server monitor log.
1064  */
1065 static void
nfsd_rt(int sotype,struct nfsrv_descript * nd,int cacherep)1066 nfsd_rt(int sotype, struct nfsrv_descript *nd, int cacherep)
1067 {
1068           struct timeval tv;
1069           struct drt *rt;
1070 
1071           rt = &nfsdrt.drt[nfsdrt.pos];
1072           if (cacherep == RC_DOIT)
1073                     rt->flag = 0;
1074           else if (cacherep == RC_REPLY)
1075                     rt->flag = DRT_CACHEREPLY;
1076           else
1077                     rt->flag = DRT_CACHEDROP;
1078           if (sotype == SOCK_STREAM)
1079                     rt->flag |= DRT_TCP;
1080           if (nd->nd_flag & ND_NFSV3)
1081                     rt->flag |= DRT_NFSV3;
1082           rt->proc = nd->nd_procnum;
1083           if (mtod(nd->nd_nam, struct sockaddr *)->sa_family == AF_INET)
1084               rt->ipadr = mtod(nd->nd_nam, struct sockaddr_in *)->sin_addr.s_addr;
1085           else
1086               rt->ipadr = INADDR_ANY;
1087           getmicrotime(&tv);
1088           rt->resptime = ((tv.tv_sec - nd->nd_starttime.tv_sec) * 1000000) +
1089                     (tv.tv_usec - nd->nd_starttime.tv_usec);
1090           rt->tstamp = tv;
1091           nfsdrt.pos = (nfsdrt.pos + 1) % NFSRTTLOGSIZ;
1092 }
1093