nfs_subs.c revision 1.8.2.1 1 /*
2 * Copyright (c) 1989 The Regents of the University of California.
3 * 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. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 * from: @(#)nfs_subs.c 7.41 (Berkeley) 5/15/91
37 * $Id: nfs_subs.c,v 1.8.2.1 1993/09/24 08:56:40 mycroft Exp $
38 */
39
40 /*
41 * These functions support the macros and help fiddle mbuf chains for
42 * the nfs op functions. They do things like create the rpc header and
43 * copy data between mbuf chains and uio lists.
44 */
45 #include "param.h"
46 #include "proc.h"
47 #include "filedesc.h"
48 #include "systm.h"
49 #include "kernel.h"
50 #include "mount.h"
51 #include "file.h"
52 #include "vnode.h"
53 #include "namei.h"
54 #include "mbuf.h"
55
56 #include "machine/cpu.h"
57
58 #include "../ufs/quota.h"
59 #include "../ufs/inode.h"
60
61 #include "rpcv2.h"
62 #include "nfsv2.h"
63 #include "nfsnode.h"
64 #include "nfs.h"
65 #include "nfsiom.h"
66 #include "xdr_subs.h"
67 #include "nfsm_subs.h"
68 #include "nfscompress.h"
69
70 #define TRUE 1
71 #define FALSE 0
72
73 /*
74 * Data items converted to xdr at startup, since they are constant
75 * This is kinda hokey, but may save a little time doing byte swaps
76 */
77 u_long nfs_procids[NFS_NPROCS];
78 u_long nfs_xdrneg1;
79 u_long rpc_call, rpc_vers, rpc_reply, rpc_msgdenied,
80 rpc_mismatch, rpc_auth_unix, rpc_msgaccepted;
81 u_long nfs_vers, nfs_prog, nfs_true, nfs_false;
82 /* And other global data */
83 static u_long *rpc_uidp = (u_long *)0;
84 static u_long nfs_xid = 1;
85 static char *rpc_unixauth;
86 extern long hostid;
87
88 extern struct proc *nfs_iodwant[NFS_MAXASYNCDAEMON];
89 extern struct nfsreq nfsreqh;
90
91 /* Function ret types */
92 static char *nfs_unixauth();
93
94 /*
95 * Maximum number of groups passed through to NFS server.
96 * According to RFC1057 it should be 16.
97 * For release 3.X systems, the maximum value is 8.
98 * For some other servers, the maximum value is 10.
99 */
100 int numgrps = 8;
101
102 /*
103 * Create the header for an rpc request packet
104 * The function nfs_unixauth() creates a unix style authorization string
105 * and returns a ptr to it.
106 * The hsiz is the size of the rest of the nfs request header.
107 * (just used to decide if a cluster is a good idea)
108 * nb: Note that the prog, vers and procid args are already in xdr byte order
109 */
110 struct mbuf *nfsm_reqh(prog, vers, procid, cred, hsiz, bpos, mb, retxid)
111 u_long prog;
112 u_long vers;
113 u_long procid;
114 struct ucred *cred;
115 int hsiz;
116 caddr_t *bpos;
117 struct mbuf **mb;
118 u_long *retxid;
119 {
120 register struct mbuf *mreq, *m;
121 register u_long *tl;
122 struct mbuf *m1;
123 char *ap;
124 int asiz, siz;
125 static char authnull[4*NFSX_UNSIGNED];
126
127 NFSMGETHDR(mreq);
128 if (cred != NOCRED) {
129 asiz = ((((cred->cr_ngroups - 1) > numgrps) ? numgrps :
130 (cred->cr_ngroups - 1)) << 2);
131 #ifdef FILLINHOST
132 asiz += nfsm_rndup(hostnamelen)+(9*NFSX_UNSIGNED);
133 #else
134 asiz += 9*NFSX_UNSIGNED;
135 #endif
136 } else
137 asiz = 4 * NFSX_UNSIGNED;
138
139 /* If we need a lot, alloc a cluster ?? */
140 if ((asiz+hsiz+RPC_SIZ) > MHLEN)
141 MCLGET(mreq, M_WAIT);
142 mreq->m_len = NFSMSIZ(mreq);
143 siz = mreq->m_len;
144 m1 = mreq;
145 /*
146 * Alloc enough mbufs
147 * We do it now to avoid all sleeps after the call to nfs_unixauth()
148 */
149 while ((asiz+RPC_SIZ) > siz) {
150 MGET(m, M_WAIT, MT_DATA);
151 m1->m_next = m;
152 m->m_len = MLEN;
153 siz += MLEN;
154 m1 = m;
155 }
156 tl = mtod(mreq, u_long *);
157 *tl++ = *retxid = txdr_unsigned(++nfs_xid);
158 *tl++ = rpc_call;
159 *tl++ = rpc_vers;
160 *tl++ = prog;
161 *tl++ = vers;
162 *tl++ = procid;
163
164 /* Now we can call nfs_unixauth() and copy it in */
165 if (cred != NOCRED)
166 ap = nfs_unixauth(cred);
167 else
168 ap = authnull;
169 m = mreq;
170 siz = m->m_len-RPC_SIZ;
171 if (asiz <= siz) {
172 bcopy(ap, (caddr_t)tl, asiz);
173 m->m_len = asiz+RPC_SIZ;
174 } else {
175 bcopy(ap, (caddr_t)tl, siz);
176 ap += siz;
177 asiz -= siz;
178 while (asiz > 0) {
179 siz = (asiz > MLEN) ? MLEN : asiz;
180 m = m->m_next;
181 bcopy(ap, mtod(m, caddr_t), siz);
182 m->m_len = siz;
183 asiz -= siz;
184 ap += siz;
185 }
186 }
187
188 /* Finally, return values */
189 *mb = m;
190 *bpos = mtod(m, caddr_t)+m->m_len;
191 return (mreq);
192 }
193
194 /*
195 * copies mbuf chain to the uio scatter/gather list
196 */
197 nfsm_mbuftouio(mrep, uiop, siz, dpos)
198 struct mbuf **mrep;
199 register struct uio *uiop;
200 int siz;
201 caddr_t *dpos;
202 {
203 register char *mbufcp, *uiocp;
204 register int xfer, left, len;
205 register struct mbuf *mp;
206 long uiosiz, rem;
207 int error = 0;
208
209 mp = *mrep;
210 mbufcp = *dpos;
211 len = mtod(mp, caddr_t)+mp->m_len-mbufcp;
212 rem = nfsm_rndup(siz)-siz;
213 while (siz > 0) {
214 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
215 return (EFBIG);
216 left = uiop->uio_iov->iov_len;
217 uiocp = uiop->uio_iov->iov_base;
218 if (left > siz)
219 left = siz;
220 uiosiz = left;
221 while (left > 0) {
222 while (len == 0) {
223 mp = mp->m_next;
224 if (mp == NULL)
225 return (EBADRPC);
226 mbufcp = mtod(mp, caddr_t);
227 len = mp->m_len;
228 }
229 xfer = (left > len) ? len : left;
230 #ifdef notdef
231 /* Not Yet.. */
232 if (uiop->uio_iov->iov_op != NULL)
233 (*(uiop->uio_iov->iov_op))
234 (mbufcp, uiocp, xfer);
235 else
236 #endif
237 if (uiop->uio_segflg == UIO_SYSSPACE)
238 bcopy(mbufcp, uiocp, xfer);
239 else
240 copyout(mbufcp, uiocp, xfer);
241 left -= xfer;
242 len -= xfer;
243 mbufcp += xfer;
244 uiocp += xfer;
245 uiop->uio_offset += xfer;
246 uiop->uio_resid -= xfer;
247 }
248 if (uiop->uio_iov->iov_len <= siz) {
249 uiop->uio_iovcnt--;
250 uiop->uio_iov++;
251 } else {
252 uiop->uio_iov->iov_base += uiosiz;
253 uiop->uio_iov->iov_len -= uiosiz;
254 }
255 siz -= uiosiz;
256 }
257 *dpos = mbufcp;
258 *mrep = mp;
259 if (rem > 0) {
260 if (len < rem)
261 error = nfs_adv(mrep, dpos, rem, len);
262 else
263 *dpos += rem;
264 }
265 return (error);
266 }
267
268 /*
269 * copies a uio scatter/gather list to an mbuf chain...
270 */
271 nfsm_uiotombuf(uiop, mq, siz, bpos)
272 register struct uio *uiop;
273 struct mbuf **mq;
274 int siz;
275 caddr_t *bpos;
276 {
277 register char *uiocp;
278 register struct mbuf *mp, *mp2;
279 register int xfer, left, len;
280 int uiosiz, clflg, rem;
281 char *cp;
282
283 if (siz > MLEN) /* or should it >= MCLBYTES ?? */
284 clflg = 1;
285 else
286 clflg = 0;
287 rem = nfsm_rndup(siz)-siz;
288 mp2 = *mq;
289 while (siz > 0) {
290 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
291 return (EINVAL);
292 left = uiop->uio_iov->iov_len;
293 uiocp = uiop->uio_iov->iov_base;
294 if (left > siz)
295 left = siz;
296 uiosiz = left;
297 while (left > 0) {
298 MGET(mp, M_WAIT, MT_DATA);
299 if (clflg)
300 MCLGET(mp, M_WAIT);
301 mp->m_len = NFSMSIZ(mp);
302 mp2->m_next = mp;
303 mp2 = mp;
304 xfer = (left > mp->m_len) ? mp->m_len : left;
305 #ifdef notdef
306 /* Not Yet.. */
307 if (uiop->uio_iov->iov_op != NULL)
308 (*(uiop->uio_iov->iov_op))
309 (uiocp, mtod(mp, caddr_t), xfer);
310 else
311 #endif
312 if (uiop->uio_segflg == UIO_SYSSPACE)
313 bcopy(uiocp, mtod(mp, caddr_t), xfer);
314 else
315 copyin(uiocp, mtod(mp, caddr_t), xfer);
316 len = mp->m_len;
317 mp->m_len = xfer;
318 left -= xfer;
319 uiocp += xfer;
320 uiop->uio_offset += xfer;
321 uiop->uio_resid -= xfer;
322 }
323 if (uiop->uio_iov->iov_len <= siz) {
324 uiop->uio_iovcnt--;
325 uiop->uio_iov++;
326 } else {
327 uiop->uio_iov->iov_base += uiosiz;
328 uiop->uio_iov->iov_len -= uiosiz;
329 }
330 siz -= uiosiz;
331 }
332 if (rem > 0) {
333 if (rem > (len-mp->m_len)) {
334 MGET(mp, M_WAIT, MT_DATA);
335 mp->m_len = 0;
336 mp2->m_next = mp;
337 }
338 cp = mtod(mp, caddr_t)+mp->m_len;
339 for (left = 0; left < rem; left++)
340 *cp++ = '\0';
341 mp->m_len += rem;
342 *bpos = cp;
343 } else
344 *bpos = mtod(mp, caddr_t)+mp->m_len;
345 *mq = mp;
346 return (0);
347 }
348
349 /*
350 * Help break down an mbuf chain by setting the first siz bytes contiguous
351 * pointed to by returned val.
352 * If Updateflg == True we can overwrite the first part of the mbuf data
353 * This is used by the macros nfsm_disect and nfsm_disecton for tough
354 * cases. (The macros use the vars. dpos and dpos2)
355 */
356 nfsm_disct(mdp, dposp, siz, left, updateflg, cp2)
357 struct mbuf **mdp;
358 caddr_t *dposp;
359 int siz;
360 int left;
361 int updateflg;
362 caddr_t *cp2;
363 {
364 register struct mbuf *mp, *mp2;
365 register int siz2, xfer;
366 register caddr_t tl;
367
368 mp = *mdp;
369 while (left == 0) {
370 *mdp = mp = mp->m_next;
371 if (mp == NULL)
372 return (EBADRPC);
373 left = mp->m_len;
374 *dposp = mtod(mp, caddr_t);
375 }
376 if (left >= siz) {
377 *cp2 = *dposp;
378 *dposp += siz;
379 } else if (mp->m_next == NULL) {
380 return (EBADRPC);
381 } else if (siz > MHLEN) {
382 panic("nfs S too big");
383 } else {
384 /* Iff update, you can overwrite, else must alloc new mbuf */
385 if (updateflg) {
386 NFSMINOFF(mp);
387 } else {
388 MGET(mp2, M_WAIT, MT_DATA);
389 mp2->m_next = mp->m_next;
390 mp->m_next = mp2;
391 mp->m_len -= left;
392 mp = mp2;
393 }
394 *cp2 = tl = mtod(mp, caddr_t);
395 bcopy(*dposp, tl, left); /* Copy what was left */
396 siz2 = siz-left;
397 tl += left;
398 mp2 = mp->m_next;
399 /* Loop around copying up the siz2 bytes */
400 while (siz2 > 0) {
401 if (mp2 == NULL)
402 return (EBADRPC);
403 xfer = (siz2 > mp2->m_len) ? mp2->m_len : siz2;
404 if (xfer > 0) {
405 bcopy(mtod(mp2, caddr_t), tl, xfer);
406 NFSMADV(mp2, xfer);
407 mp2->m_len -= xfer;
408 tl += xfer;
409 siz2 -= xfer;
410 }
411 if (siz2 > 0)
412 mp2 = mp2->m_next;
413 }
414 mp->m_len = siz;
415 *mdp = mp2;
416 *dposp = mtod(mp2, caddr_t);
417 }
418 return (0);
419 }
420
421 /*
422 * Advance the position in the mbuf chain.
423 */
424 nfs_adv(mdp, dposp, offs, left)
425 struct mbuf **mdp;
426 caddr_t *dposp;
427 int offs;
428 int left;
429 {
430 register struct mbuf *m;
431 register int s;
432
433 m = *mdp;
434 s = left;
435 while (s < offs) {
436 offs -= s;
437 m = m->m_next;
438 if (m == NULL)
439 return (EBADRPC);
440 s = m->m_len;
441 }
442 *mdp = m;
443 *dposp = mtod(m, caddr_t)+offs;
444 return (0);
445 }
446
447 /*
448 * Copy a string into mbufs for the hard cases...
449 */
450 nfsm_strtmbuf(mb, bpos, cp, siz)
451 struct mbuf **mb;
452 char **bpos;
453 char *cp;
454 long siz;
455 {
456 register struct mbuf *m1, *m2;
457 long left, xfer, len, tlen;
458 u_long *tl;
459 int putsize;
460
461 putsize = 1;
462 m2 = *mb;
463 left = NFSMSIZ(m2)-m2->m_len;
464 if (left > 0) {
465 tl = ((u_long *)(*bpos));
466 *tl++ = txdr_unsigned(siz);
467 putsize = 0;
468 left -= NFSX_UNSIGNED;
469 m2->m_len += NFSX_UNSIGNED;
470 if (left > 0) {
471 bcopy(cp, (caddr_t) tl, left);
472 siz -= left;
473 cp += left;
474 m2->m_len += left;
475 left = 0;
476 }
477 }
478 /* Loop arround adding mbufs */
479 while (siz > 0) {
480 MGET(m1, M_WAIT, MT_DATA);
481 if (siz > MLEN)
482 MCLGET(m1, M_WAIT);
483 m1->m_len = NFSMSIZ(m1);
484 m2->m_next = m1;
485 m2 = m1;
486 tl = mtod(m1, u_long *);
487 tlen = 0;
488 if (putsize) {
489 *tl++ = txdr_unsigned(siz);
490 m1->m_len -= NFSX_UNSIGNED;
491 tlen = NFSX_UNSIGNED;
492 putsize = 0;
493 }
494 if (siz < m1->m_len) {
495 len = nfsm_rndup(siz);
496 xfer = siz;
497 if (xfer < len)
498 *(tl+(xfer>>2)) = 0;
499 } else {
500 xfer = len = m1->m_len;
501 }
502 bcopy(cp, (caddr_t) tl, xfer);
503 m1->m_len = len+tlen;
504 siz -= xfer;
505 cp += xfer;
506 }
507 *mb = m1;
508 *bpos = mtod(m1, caddr_t)+m1->m_len;
509 return (0);
510 }
511
512 /*
513 * Called once to initialize data structures...
514 */
515 nfs_init()
516 {
517 register int i;
518
519 rpc_vers = txdr_unsigned(RPC_VER2);
520 rpc_call = txdr_unsigned(RPC_CALL);
521 rpc_reply = txdr_unsigned(RPC_REPLY);
522 rpc_msgdenied = txdr_unsigned(RPC_MSGDENIED);
523 rpc_msgaccepted = txdr_unsigned(RPC_MSGACCEPTED);
524 rpc_mismatch = txdr_unsigned(RPC_MISMATCH);
525 rpc_auth_unix = txdr_unsigned(RPCAUTH_UNIX);
526 nfs_vers = txdr_unsigned(NFS_VER2);
527 nfs_prog = txdr_unsigned(NFS_PROG);
528 nfs_true = txdr_unsigned(TRUE);
529 nfs_false = txdr_unsigned(FALSE);
530 /* Loop thru nfs procids */
531 for (i = 0; i < NFS_NPROCS; i++)
532 nfs_procids[i] = txdr_unsigned(i);
533 /* Ensure async daemons disabled */
534 nfs_xdrneg1 = txdr_unsigned(-1);
535 #ifdef NFSCLIENT
536 for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
537 nfs_iodwant[i] = (struct proc *)0;
538 nfs_nhinit(); /* Init the nfsnode table */
539 #endif /* NFSCLIENT */
540 #ifdef NFSSERVER
541 nfsrv_initcache(); /* Init the server request cache */
542 #endif /*NFSSERVER */
543 /*
544 * Initialize reply list and start timer
545 */
546 nfsreqh.r_prev = nfsreqh.r_next = &nfsreqh;
547 nfs_timer();
548 }
549
550 /*
551 * Fill in the rest of the rpc_unixauth and return it
552 */
553 static char *nfs_unixauth(cr)
554 register struct ucred *cr;
555 {
556 register u_long *tl;
557 register int i;
558 int ngr;
559
560 /* Maybe someday there should be a cache of AUTH_SHORT's */
561 if ((tl = rpc_uidp) == NULL) {
562 #ifdef FILLINHOST
563 i = nfsm_rndup(hostnamelen)+(25*NFSX_UNSIGNED);
564 #else
565 i = 25*NFSX_UNSIGNED;
566 #endif
567 MALLOC(tl, u_long *, i, M_TEMP, M_WAITOK);
568 bzero((caddr_t)tl, i);
569 rpc_unixauth = (caddr_t)tl;
570 *tl++ = txdr_unsigned(RPCAUTH_UNIX);
571 tl++; /* Fill in size later */
572 *tl++ = hostid;
573 #ifdef FILLINHOST
574 *tl++ = txdr_unsigned(hostnamelen);
575 i = nfsm_rndup(hostnamelen);
576 bcopy(hostname, (caddr_t)tl, hostnamelen);
577 tl += (i>>2);
578 #else
579 *tl++ = 0;
580 #endif
581 rpc_uidp = tl;
582 }
583 *tl++ = txdr_unsigned(cr->cr_uid);
584 *tl++ = txdr_unsigned(cr->cr_groups[0]);
585 ngr = ((cr->cr_ngroups - 1) > numgrps) ? numgrps : (cr->cr_ngroups - 1);
586 *tl++ = txdr_unsigned(ngr);
587 for (i = 1; i <= ngr; i++)
588 *tl++ = txdr_unsigned(cr->cr_groups[i]);
589 /* And add the AUTH_NULL */
590 *tl++ = 0;
591 *tl = 0;
592 i = (((caddr_t)tl)-rpc_unixauth)-12;
593 tl = (u_long *)(rpc_unixauth+4);
594 *tl = txdr_unsigned(i);
595 return (rpc_unixauth);
596 }
597
598 /*
599 * Set up nameidata for a namei() call and do it
600 */
601 nfs_namei(ndp, fhp, len, mdp, dposp, p)
602 register struct nameidata *ndp;
603 fhandle_t *fhp;
604 int len;
605 struct mbuf **mdp;
606 caddr_t *dposp;
607 struct proc *p;
608 {
609 register int i, rem;
610 register struct mbuf *md;
611 register char *fromcp, *tocp;
612 struct vnode *dp;
613 int flag;
614 int error;
615
616 flag = ndp->ni_nameiop & OPMASK;
617 MALLOC(ndp->ni_pnbuf, char *, len + 1, M_NAMEI, M_WAITOK);
618 /*
619 * Copy the name from the mbuf list to ndp->ni_pnbuf
620 * and set the various ndp fields appropriately.
621 */
622 fromcp = *dposp;
623 tocp = ndp->ni_pnbuf;
624 md = *mdp;
625 rem = mtod(md, caddr_t) + md->m_len - fromcp;
626 for (i = 0; i < len; i++) {
627 while (rem == 0) {
628 md = md->m_next;
629 if (md == NULL) {
630 error = EBADRPC;
631 goto out;
632 }
633 fromcp = mtod(md, caddr_t);
634 rem = md->m_len;
635 }
636 if (*fromcp == '\0' || *fromcp == '/') {
637 error = EINVAL;
638 goto out;
639 }
640 if (*fromcp & 0200)
641 if ((*fromcp&0377) == ('/'|0200) || flag != DELETE) {
642 error = EINVAL;
643 goto out;
644 }
645 *tocp++ = *fromcp++;
646 rem--;
647 }
648 *tocp = '\0';
649 *mdp = md;
650 *dposp = fromcp;
651 len = nfsm_rndup(len)-len;
652 if (len > 0) {
653 if (rem >= len)
654 *dposp += len;
655 else if (error = nfs_adv(mdp, dposp, len, rem))
656 goto out;
657 }
658 ndp->ni_pathlen = tocp - ndp->ni_pnbuf;
659 ndp->ni_ptr = ndp->ni_pnbuf;
660 /*
661 * Extract and set starting directory.
662 */
663 if (error = nfsrv_fhtovp(fhp, FALSE, &dp, ndp->ni_cred))
664 goto out;
665 if (dp->v_type != VDIR) {
666 vrele(dp);
667 error = ENOTDIR;
668 goto out;
669 }
670 ndp->ni_startdir = dp;
671 ndp->ni_nameiop |= (NOCROSSMOUNT | REMOTE);
672 /*
673 * And call lookup() to do the real work
674 */
675 if (error = lookup(ndp, p))
676 goto out;
677 /*
678 * Check for encountering a symbolic link
679 */
680 if (ndp->ni_more) {
681 if ((ndp->ni_nameiop & LOCKPARENT) && ndp->ni_pathlen == 1)
682 vput(ndp->ni_dvp);
683 else
684 vrele(ndp->ni_dvp);
685 vput(ndp->ni_vp);
686 ndp->ni_vp = NULL;
687 error = EINVAL;
688 goto out;
689 }
690 /*
691 * Check for saved name request
692 */
693 if (ndp->ni_nameiop & (SAVENAME | SAVESTART)) {
694 ndp->ni_nameiop |= HASBUF;
695 return (0);
696 }
697 out:
698 FREE(ndp->ni_pnbuf, M_NAMEI);
699 return (error);
700 }
701
702 /*
703 * A fiddled version of m_adj() that ensures null fill to a long
704 * boundary and only trims off the back end
705 */
706 nfsm_adj(mp, len, nul)
707 struct mbuf *mp;
708 register int len;
709 int nul;
710 {
711 register struct mbuf *m;
712 register int count, i;
713 register char *cp;
714
715 /*
716 * Trim from tail. Scan the mbuf chain,
717 * calculating its length and finding the last mbuf.
718 * If the adjustment only affects this mbuf, then just
719 * adjust and return. Otherwise, rescan and truncate
720 * after the remaining size.
721 */
722 count = 0;
723 m = mp;
724 for (;;) {
725 count += m->m_len;
726 if (m->m_next == (struct mbuf *)0)
727 break;
728 m = m->m_next;
729 }
730 if (m->m_len > len) {
731 m->m_len -= len;
732 if (nul > 0) {
733 cp = mtod(m, caddr_t)+m->m_len-nul;
734 for (i = 0; i < nul; i++)
735 *cp++ = '\0';
736 }
737 return;
738 }
739 count -= len;
740 if (count < 0)
741 count = 0;
742 /*
743 * Correct length for chain is "count".
744 * Find the mbuf with last data, adjust its length,
745 * and toss data from remaining mbufs on chain.
746 */
747 for (m = mp; m; m = m->m_next) {
748 if (m->m_len >= count) {
749 m->m_len = count;
750 if (nul > 0) {
751 cp = mtod(m, caddr_t)+m->m_len-nul;
752 for (i = 0; i < nul; i++)
753 *cp++ = '\0';
754 }
755 break;
756 }
757 count -= m->m_len;
758 }
759 while (m = m->m_next)
760 m->m_len = 0;
761 }
762
763 /*
764 * nfsrv_fhtovp() - convert a fh to a vnode ptr (optionally locked)
765 * - look up fsid in mount list (if not found ret error)
766 * - check that it is exported
767 * - get vp by calling VFS_FHTOVP() macro
768 * - if not lockflag unlock it with VOP_UNLOCK()
769 * - if cred->cr_uid == 0 set it to m_exroot
770 */
771 nfsrv_fhtovp(fhp, lockflag, vpp, cred)
772 fhandle_t *fhp;
773 int lockflag;
774 struct vnode **vpp;
775 struct ucred *cred;
776 {
777 register struct mount *mp;
778
779 if ((mp = getvfs(&fhp->fh_fsid)) == NULL)
780 return (ESTALE);
781 if ((mp->mnt_flag & MNT_EXPORTED) == 0)
782 return (EACCES);
783 if (VFS_FHTOVP(mp, &fhp->fh_fid, vpp))
784 return (ESTALE);
785 if (cred->cr_uid == 0)
786 cred->cr_uid = mp->mnt_exroot;
787 if (!lockflag)
788 VOP_UNLOCK(*vpp);
789 return (0);
790 }
791
792 /*
793 * These two functions implement nfs rpc compression.
794 * The algorithm is a trivial run length encoding of '\0' bytes. The high
795 * order nibble of hex "e" is or'd with the number of zeroes - 2 in four
796 * bits. (2 - 17 zeros) Any data byte with a high order nibble of hex "e"
797 * is byte stuffed.
798 * The compressed data is padded with 0x0 bytes to an even multiple of
799 * 4 bytes in length to avoid any weird long pointer alignments.
800 * If compression/uncompression is unsuccessful, the original mbuf list
801 * is returned.
802 * The first four bytes (the XID) are left uncompressed and the fifth
803 * byte is set to 0x1 for request and 0x2 for reply.
804 * An uncompressed RPC will always have the fifth byte == 0x0.
805 */
806 struct mbuf *
807 nfs_compress(m0)
808 struct mbuf *m0;
809 {
810 register u_char ch, nextch;
811 register int i, rlelast;
812 register u_char *ip, *op;
813 register int ileft, oleft, noteof;
814 register struct mbuf *m, *om;
815 struct mbuf **mp, *retm;
816 int olen, clget;
817
818 i = rlelast = 0;
819 noteof = 1;
820 m = m0;
821 if (m->m_len < 12)
822 return (m0);
823 if (m->m_pkthdr.len >= MINCLSIZE)
824 clget = 1;
825 else
826 clget = 0;
827 ileft = m->m_len - 9;
828 ip = mtod(m, u_char *);
829 MGETHDR(om, M_WAIT, MT_DATA);
830 if (clget)
831 MCLGET(om, M_WAIT);
832 retm = om;
833 mp = &om->m_next;
834 olen = om->m_len = 5;
835 oleft = M_TRAILINGSPACE(om);
836 op = mtod(om, u_char *);
837 *((u_long *)op) = *((u_long *)ip);
838 ip += 7;
839 op += 4;
840 *op++ = *ip++ + 1;
841 nextch = *ip++;
842 while (noteof) {
843 ch = nextch;
844 if (ileft == 0) {
845 do {
846 m = m->m_next;
847 } while (m && m->m_len == 0);
848 if (m) {
849 ileft = m->m_len;
850 ip = mtod(m, u_char *);
851 } else {
852 noteof = 0;
853 nextch = 0x1;
854 goto doit;
855 }
856 }
857 nextch = *ip++;
858 ileft--;
859 doit:
860 if (ch == '\0') {
861 if (++i == NFSC_MAX || nextch != '\0') {
862 if (i < 2) {
863 nfscput('\0');
864 } else {
865 if (rlelast == i) {
866 nfscput('\0');
867 i--;
868 }
869 if (NFSCRLE(i) == (nextch & 0xff)) {
870 i--;
871 if (i < 2) {
872 nfscput('\0');
873 } else {
874 nfscput(NFSCRLE(i));
875 }
876 nfscput('\0');
877 rlelast = 0;
878 } else {
879 nfscput(NFSCRLE(i));
880 rlelast = i;
881 }
882 }
883 i = 0;
884 }
885 } else {
886 if ((ch & NFSCRL) == NFSCRL) {
887 nfscput(ch);
888 }
889 nfscput(ch);
890 i = rlelast = 0;
891 }
892 }
893 if (olen < m0->m_pkthdr.len) {
894 m_freem(m0);
895 if (i = (olen & 0x3)) {
896 i = 4 - i;
897 while (i-- > 0) {
898 nfscput('\0');
899 }
900 }
901 retm->m_pkthdr.len = olen;
902 retm->m_pkthdr.rcvif = (struct ifnet *)0;
903 return (retm);
904 } else {
905 m_freem(retm);
906 return (m0);
907 }
908 }
909
910 struct mbuf *
911 nfs_uncompress(m0)
912 struct mbuf *m0;
913 {
914 register u_char cp, nextcp, *ip, *op;
915 register struct mbuf *m, *om;
916 struct mbuf *retm, **mp;
917 int i, j, noteof, clget, ileft, oleft, olen;
918
919 m = m0;
920 i = 0;
921 while (m && i < MINCLSIZE) {
922 i += m->m_len;
923 m = m->m_next;
924 }
925 if (i < 6)
926 return (m0);
927 if (i >= MINCLSIZE)
928 clget = 1;
929 else
930 clget = 0;
931 m = m0;
932 MGET(om, M_WAIT, MT_DATA);
933 if (clget)
934 MCLGET(om, M_WAIT);
935 olen = om->m_len = 8;
936 oleft = M_TRAILINGSPACE(om);
937 op = mtod(om, u_char *);
938 retm = om;
939 mp = &om->m_next;
940 if (m->m_len >= 6) {
941 ileft = m->m_len - 6;
942 ip = mtod(m, u_char *);
943 *((u_long *)op) = *((u_long *)ip);
944 bzero(op + 4, 3);
945 ip += 4;
946 op += 7;
947 if (*ip == '\0') {
948 m_freem(om);
949 return (m0);
950 }
951 *op++ = *ip++ - 1;
952 cp = *ip++;
953 } else {
954 ileft = m->m_len;
955 ip = mtod(m, u_char *);
956 nfscget(*op++);
957 nfscget(*op++);
958 nfscget(*op++);
959 nfscget(*op++);
960 bzero(op, 3);
961 op += 3;
962 nfscget(*op);
963 if (*op == '\0') {
964 m_freem(om);
965 return (m0);
966 }
967 (*op)--;
968 op++;
969 nfscget(cp);
970 }
971 noteof = 1;
972 while (noteof) {
973 if ((cp & NFSCRL) == NFSCRL) {
974 nfscget(nextcp);
975 if (cp == nextcp) {
976 nfscput(cp);
977 goto readit;
978 } else {
979 i = (cp & 0xf) + 2;
980 for (j = 0; j < i; j++) {
981 nfscput('\0');
982 }
983 cp = nextcp;
984 }
985 } else {
986 nfscput(cp);
987 readit:
988 nfscget(cp);
989 }
990 }
991 m_freem(m0);
992 if (i = (olen & 0x3))
993 om->m_len -= i;
994 return (retm);
995 }
996