nfs_subs.c revision 1.5 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 1.5 1993/07/13 10:04:28 cgd 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 "../ufs/quota.h"
57 #include "../ufs/inode.h"
58
59 #include "rpcv2.h"
60 #include "nfsv2.h"
61 #include "nfsnode.h"
62 #include "nfs.h"
63 #include "nfsiom.h"
64 #include "xdr_subs.h"
65 #include "nfsm_subs.h"
66 #include "nfscompress.h"
67
68 #define TRUE 1
69 #define FALSE 0
70
71 /*
72 * Data items converted to xdr at startup, since they are constant
73 * This is kinda hokey, but may save a little time doing byte swaps
74 */
75 u_long nfs_procids[NFS_NPROCS];
76 u_long nfs_xdrneg1;
77 u_long rpc_call, rpc_vers, rpc_reply, rpc_msgdenied,
78 rpc_mismatch, rpc_auth_unix, rpc_msgaccepted;
79 u_long nfs_vers, nfs_prog, nfs_true, nfs_false;
80 /* And other global data */
81 static u_long *rpc_uidp = (u_long *)0;
82 static u_long nfs_xid = 1;
83 static char *rpc_unixauth;
84 extern long hostid;
85
86 extern struct proc *nfs_iodwant[NFS_MAXASYNCDAEMON];
87 extern struct nfsreq nfsreqh;
88
89 /* Function ret types */
90 static char *nfs_unixauth();
91
92 /*
93 * Maximum number of groups passed through to NFS server.
94 * According to RFC1057 it should be 16.
95 * For release 3.X systems, the maximum value is 8.
96 * For some other servers, the maximum value is 10.
97 */
98 int numgrps = 8;
99
100 /*
101 * Create the header for an rpc request packet
102 * The function nfs_unixauth() creates a unix style authorization string
103 * and returns a ptr to it.
104 * The hsiz is the size of the rest of the nfs request header.
105 * (just used to decide if a cluster is a good idea)
106 * nb: Note that the prog, vers and procid args are already in xdr byte order
107 */
108 struct mbuf *nfsm_reqh(prog, vers, procid, cred, hsiz, bpos, mb, retxid)
109 u_long prog;
110 u_long vers;
111 u_long procid;
112 struct ucred *cred;
113 int hsiz;
114 caddr_t *bpos;
115 struct mbuf **mb;
116 u_long *retxid;
117 {
118 register struct mbuf *mreq, *m;
119 register u_long *tl;
120 struct mbuf *m1;
121 char *ap;
122 int asiz, siz;
123 static char authnull[4*NFSX_UNSIGNED];
124
125 NFSMGETHDR(mreq);
126 if (cred != NOCRED) {
127 asiz = ((((cred->cr_ngroups - 1) > numgrps) ? numgrps :
128 (cred->cr_ngroups - 1)) << 2);
129 #ifdef FILLINHOST
130 asiz += nfsm_rndup(hostnamelen)+(9*NFSX_UNSIGNED);
131 #else
132 asiz += 9*NFSX_UNSIGNED;
133 #endif
134 } else
135 asiz = 4 * NFSX_UNSIGNED;
136
137 /* If we need a lot, alloc a cluster ?? */
138 if ((asiz+hsiz+RPC_SIZ) > MHLEN)
139 MCLGET(mreq, M_WAIT);
140 mreq->m_len = NFSMSIZ(mreq);
141 siz = mreq->m_len;
142 m1 = mreq;
143 /*
144 * Alloc enough mbufs
145 * We do it now to avoid all sleeps after the call to nfs_unixauth()
146 */
147 while ((asiz+RPC_SIZ) > siz) {
148 MGET(m, M_WAIT, MT_DATA);
149 m1->m_next = m;
150 m->m_len = MLEN;
151 siz += MLEN;
152 m1 = m;
153 }
154 tl = mtod(mreq, u_long *);
155 *tl++ = *retxid = txdr_unsigned(++nfs_xid);
156 *tl++ = rpc_call;
157 *tl++ = rpc_vers;
158 *tl++ = prog;
159 *tl++ = vers;
160 *tl++ = procid;
161
162 /* Now we can call nfs_unixauth() and copy it in */
163 if (cred != NOCRED)
164 ap = nfs_unixauth(cred);
165 else
166 ap = authnull;
167 m = mreq;
168 siz = m->m_len-RPC_SIZ;
169 if (asiz <= siz) {
170 bcopy(ap, (caddr_t)tl, asiz);
171 m->m_len = asiz+RPC_SIZ;
172 } else {
173 bcopy(ap, (caddr_t)tl, siz);
174 ap += siz;
175 asiz -= siz;
176 while (asiz > 0) {
177 siz = (asiz > MLEN) ? MLEN : asiz;
178 m = m->m_next;
179 bcopy(ap, mtod(m, caddr_t), siz);
180 m->m_len = siz;
181 asiz -= siz;
182 ap += siz;
183 }
184 }
185
186 /* Finally, return values */
187 *mb = m;
188 *bpos = mtod(m, caddr_t)+m->m_len;
189 return (mreq);
190 }
191
192 /*
193 * copies mbuf chain to the uio scatter/gather list
194 */
195 nfsm_mbuftouio(mrep, uiop, siz, dpos)
196 struct mbuf **mrep;
197 register struct uio *uiop;
198 int siz;
199 caddr_t *dpos;
200 {
201 register char *mbufcp, *uiocp;
202 register int xfer, left, len;
203 register struct mbuf *mp;
204 long uiosiz, rem;
205 int error = 0;
206
207 mp = *mrep;
208 mbufcp = *dpos;
209 len = mtod(mp, caddr_t)+mp->m_len-mbufcp;
210 rem = nfsm_rndup(siz)-siz;
211 while (siz > 0) {
212 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
213 return (EFBIG);
214 left = uiop->uio_iov->iov_len;
215 uiocp = uiop->uio_iov->iov_base;
216 if (left > siz)
217 left = siz;
218 uiosiz = left;
219 while (left > 0) {
220 while (len == 0) {
221 mp = mp->m_next;
222 if (mp == NULL)
223 return (EBADRPC);
224 mbufcp = mtod(mp, caddr_t);
225 len = mp->m_len;
226 }
227 xfer = (left > len) ? len : left;
228 #ifdef notdef
229 /* Not Yet.. */
230 if (uiop->uio_iov->iov_op != NULL)
231 (*(uiop->uio_iov->iov_op))
232 (mbufcp, uiocp, xfer);
233 else
234 #endif
235 if (uiop->uio_segflg == UIO_SYSSPACE)
236 bcopy(mbufcp, uiocp, xfer);
237 else
238 copyout(mbufcp, uiocp, xfer);
239 left -= xfer;
240 len -= xfer;
241 mbufcp += xfer;
242 uiocp += xfer;
243 uiop->uio_offset += xfer;
244 uiop->uio_resid -= xfer;
245 }
246 if (uiop->uio_iov->iov_len <= siz) {
247 uiop->uio_iovcnt--;
248 uiop->uio_iov++;
249 } else {
250 uiop->uio_iov->iov_base += uiosiz;
251 uiop->uio_iov->iov_len -= uiosiz;
252 }
253 siz -= uiosiz;
254 }
255 *dpos = mbufcp;
256 *mrep = mp;
257 if (rem > 0) {
258 if (len < rem)
259 error = nfs_adv(mrep, dpos, rem, len);
260 else
261 *dpos += rem;
262 }
263 return (error);
264 }
265
266 /*
267 * copies a uio scatter/gather list to an mbuf chain...
268 */
269 nfsm_uiotombuf(uiop, mq, siz, bpos)
270 register struct uio *uiop;
271 struct mbuf **mq;
272 int siz;
273 caddr_t *bpos;
274 {
275 register char *uiocp;
276 register struct mbuf *mp, *mp2;
277 register int xfer, left, len;
278 int uiosiz, clflg, rem;
279 char *cp;
280
281 if (siz > MLEN) /* or should it >= MCLBYTES ?? */
282 clflg = 1;
283 else
284 clflg = 0;
285 rem = nfsm_rndup(siz)-siz;
286 mp2 = *mq;
287 while (siz > 0) {
288 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
289 return (EINVAL);
290 left = uiop->uio_iov->iov_len;
291 uiocp = uiop->uio_iov->iov_base;
292 if (left > siz)
293 left = siz;
294 uiosiz = left;
295 while (left > 0) {
296 MGET(mp, M_WAIT, MT_DATA);
297 if (clflg)
298 MCLGET(mp, M_WAIT);
299 mp->m_len = NFSMSIZ(mp);
300 mp2->m_next = mp;
301 mp2 = mp;
302 xfer = (left > mp->m_len) ? mp->m_len : left;
303 #ifdef notdef
304 /* Not Yet.. */
305 if (uiop->uio_iov->iov_op != NULL)
306 (*(uiop->uio_iov->iov_op))
307 (uiocp, mtod(mp, caddr_t), xfer);
308 else
309 #endif
310 if (uiop->uio_segflg == UIO_SYSSPACE)
311 bcopy(uiocp, mtod(mp, caddr_t), xfer);
312 else
313 copyin(uiocp, mtod(mp, caddr_t), xfer);
314 len = mp->m_len;
315 mp->m_len = xfer;
316 left -= xfer;
317 uiocp += xfer;
318 uiop->uio_offset += xfer;
319 uiop->uio_resid -= xfer;
320 }
321 if (uiop->uio_iov->iov_len <= siz) {
322 uiop->uio_iovcnt--;
323 uiop->uio_iov++;
324 } else {
325 uiop->uio_iov->iov_base += uiosiz;
326 uiop->uio_iov->iov_len -= uiosiz;
327 }
328 siz -= uiosiz;
329 }
330 if (rem > 0) {
331 if (rem > (len-mp->m_len)) {
332 MGET(mp, M_WAIT, MT_DATA);
333 mp->m_len = 0;
334 mp2->m_next = mp;
335 }
336 cp = mtod(mp, caddr_t)+mp->m_len;
337 for (left = 0; left < rem; left++)
338 *cp++ = '\0';
339 mp->m_len += rem;
340 *bpos = cp;
341 } else
342 *bpos = mtod(mp, caddr_t)+mp->m_len;
343 *mq = mp;
344 return (0);
345 }
346
347 /*
348 * Help break down an mbuf chain by setting the first siz bytes contiguous
349 * pointed to by returned val.
350 * If Updateflg == True we can overwrite the first part of the mbuf data
351 * This is used by the macros nfsm_disect and nfsm_disecton for tough
352 * cases. (The macros use the vars. dpos and dpos2)
353 */
354 nfsm_disct(mdp, dposp, siz, left, updateflg, cp2)
355 struct mbuf **mdp;
356 caddr_t *dposp;
357 int siz;
358 int left;
359 int updateflg;
360 caddr_t *cp2;
361 {
362 register struct mbuf *mp, *mp2;
363 register int siz2, xfer;
364 register caddr_t tl;
365
366 mp = *mdp;
367 while (left == 0) {
368 *mdp = mp = mp->m_next;
369 if (mp == NULL)
370 return (EBADRPC);
371 left = mp->m_len;
372 *dposp = mtod(mp, caddr_t);
373 }
374 if (left >= siz) {
375 *cp2 = *dposp;
376 *dposp += siz;
377 } else if (mp->m_next == NULL) {
378 return (EBADRPC);
379 } else if (siz > MHLEN) {
380 panic("nfs S too big");
381 } else {
382 /* Iff update, you can overwrite, else must alloc new mbuf */
383 if (updateflg) {
384 NFSMINOFF(mp);
385 } else {
386 MGET(mp2, M_WAIT, MT_DATA);
387 mp2->m_next = mp->m_next;
388 mp->m_next = mp2;
389 mp->m_len -= left;
390 mp = mp2;
391 }
392 *cp2 = tl = mtod(mp, caddr_t);
393 bcopy(*dposp, tl, left); /* Copy what was left */
394 siz2 = siz-left;
395 tl += left;
396 mp2 = mp->m_next;
397 /* Loop around copying up the siz2 bytes */
398 while (siz2 > 0) {
399 if (mp2 == NULL)
400 return (EBADRPC);
401 xfer = (siz2 > mp2->m_len) ? mp2->m_len : siz2;
402 if (xfer > 0) {
403 bcopy(mtod(mp2, caddr_t), tl, xfer);
404 NFSMADV(mp2, xfer);
405 mp2->m_len -= xfer;
406 tl += xfer;
407 siz2 -= xfer;
408 }
409 if (siz2 > 0)
410 mp2 = mp2->m_next;
411 }
412 mp->m_len = siz;
413 *mdp = mp2;
414 *dposp = mtod(mp2, caddr_t);
415 }
416 return (0);
417 }
418
419 /*
420 * Advance the position in the mbuf chain.
421 */
422 nfs_adv(mdp, dposp, offs, left)
423 struct mbuf **mdp;
424 caddr_t *dposp;
425 int offs;
426 int left;
427 {
428 register struct mbuf *m;
429 register int s;
430
431 m = *mdp;
432 s = left;
433 while (s < offs) {
434 offs -= s;
435 m = m->m_next;
436 if (m == NULL)
437 return (EBADRPC);
438 s = m->m_len;
439 }
440 *mdp = m;
441 *dposp = mtod(m, caddr_t)+offs;
442 return (0);
443 }
444
445 /*
446 * Copy a string into mbufs for the hard cases...
447 */
448 nfsm_strtmbuf(mb, bpos, cp, siz)
449 struct mbuf **mb;
450 char **bpos;
451 char *cp;
452 long siz;
453 {
454 register struct mbuf *m1, *m2;
455 long left, xfer, len, tlen;
456 u_long *tl;
457 int putsize;
458
459 putsize = 1;
460 m2 = *mb;
461 left = NFSMSIZ(m2)-m2->m_len;
462 if (left > 0) {
463 tl = ((u_long *)(*bpos));
464 *tl++ = txdr_unsigned(siz);
465 putsize = 0;
466 left -= NFSX_UNSIGNED;
467 m2->m_len += NFSX_UNSIGNED;
468 if (left > 0) {
469 bcopy(cp, (caddr_t) tl, left);
470 siz -= left;
471 cp += left;
472 m2->m_len += left;
473 left = 0;
474 }
475 }
476 /* Loop arround adding mbufs */
477 while (siz > 0) {
478 MGET(m1, M_WAIT, MT_DATA);
479 if (siz > MLEN)
480 MCLGET(m1, M_WAIT);
481 m1->m_len = NFSMSIZ(m1);
482 m2->m_next = m1;
483 m2 = m1;
484 tl = mtod(m1, u_long *);
485 tlen = 0;
486 if (putsize) {
487 *tl++ = txdr_unsigned(siz);
488 m1->m_len -= NFSX_UNSIGNED;
489 tlen = NFSX_UNSIGNED;
490 putsize = 0;
491 }
492 if (siz < m1->m_len) {
493 len = nfsm_rndup(siz);
494 xfer = siz;
495 if (xfer < len)
496 *(tl+(xfer>>2)) = 0;
497 } else {
498 xfer = len = m1->m_len;
499 }
500 bcopy(cp, (caddr_t) tl, xfer);
501 m1->m_len = len+tlen;
502 siz -= xfer;
503 cp += xfer;
504 }
505 *mb = m1;
506 *bpos = mtod(m1, caddr_t)+m1->m_len;
507 return (0);
508 }
509
510 /*
511 * Called once to initialize data structures...
512 */
513 nfs_init()
514 {
515 register int i;
516
517 rpc_vers = txdr_unsigned(RPC_VER2);
518 rpc_call = txdr_unsigned(RPC_CALL);
519 rpc_reply = txdr_unsigned(RPC_REPLY);
520 rpc_msgdenied = txdr_unsigned(RPC_MSGDENIED);
521 rpc_msgaccepted = txdr_unsigned(RPC_MSGACCEPTED);
522 rpc_mismatch = txdr_unsigned(RPC_MISMATCH);
523 rpc_auth_unix = txdr_unsigned(RPCAUTH_UNIX);
524 nfs_vers = txdr_unsigned(NFS_VER2);
525 nfs_prog = txdr_unsigned(NFS_PROG);
526 nfs_true = txdr_unsigned(TRUE);
527 nfs_false = txdr_unsigned(FALSE);
528 /* Loop thru nfs procids */
529 for (i = 0; i < NFS_NPROCS; i++)
530 nfs_procids[i] = txdr_unsigned(i);
531 /* Ensure async daemons disabled */
532 nfs_xdrneg1 = txdr_unsigned(-1);
533 #ifdef NFSCLIENT
534 for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
535 nfs_iodwant[i] = (struct proc *)0;
536 nfs_nhinit(); /* Init the nfsnode table */
537 #endif /* NFSCLIENT */
538 #ifdef NFSSERVER
539 nfsrv_initcache(); /* Init the server request cache */
540 #endif /*NFSSERVER */
541 /*
542 * Initialize reply list and start timer
543 */
544 nfsreqh.r_prev = nfsreqh.r_next = &nfsreqh;
545 nfs_timer();
546 }
547
548 /*
549 * Fill in the rest of the rpc_unixauth and return it
550 */
551 static char *nfs_unixauth(cr)
552 register struct ucred *cr;
553 {
554 register u_long *tl;
555 register int i;
556 int ngr;
557
558 /* Maybe someday there should be a cache of AUTH_SHORT's */
559 if ((tl = rpc_uidp) == NULL) {
560 #ifdef FILLINHOST
561 i = nfsm_rndup(hostnamelen)+(25*NFSX_UNSIGNED);
562 #else
563 i = 25*NFSX_UNSIGNED;
564 #endif
565 MALLOC(tl, u_long *, i, M_TEMP, M_WAITOK);
566 bzero((caddr_t)tl, i);
567 rpc_unixauth = (caddr_t)tl;
568 *tl++ = txdr_unsigned(RPCAUTH_UNIX);
569 tl++; /* Fill in size later */
570 *tl++ = hostid;
571 #ifdef FILLINHOST
572 *tl++ = txdr_unsigned(hostnamelen);
573 i = nfsm_rndup(hostnamelen);
574 bcopy(hostname, (caddr_t)tl, hostnamelen);
575 tl += (i>>2);
576 #else
577 *tl++ = 0;
578 #endif
579 rpc_uidp = tl;
580 }
581 *tl++ = txdr_unsigned(cr->cr_uid);
582 *tl++ = txdr_unsigned(cr->cr_groups[0]);
583 ngr = ((cr->cr_ngroups - 1) > numgrps) ? numgrps : (cr->cr_ngroups - 1);
584 *tl++ = txdr_unsigned(ngr);
585 for (i = 1; i <= ngr; i++)
586 *tl++ = txdr_unsigned(cr->cr_groups[i]);
587 /* And add the AUTH_NULL */
588 *tl++ = 0;
589 *tl = 0;
590 i = (((caddr_t)tl)-rpc_unixauth)-12;
591 tl = (u_long *)(rpc_unixauth+4);
592 *tl = txdr_unsigned(i);
593 return (rpc_unixauth);
594 }
595
596 /*
597 * Set up nameidata for a namei() call and do it
598 */
599 nfs_namei(ndp, fhp, len, mdp, dposp, p)
600 register struct nameidata *ndp;
601 fhandle_t *fhp;
602 int len;
603 struct mbuf **mdp;
604 caddr_t *dposp;
605 struct proc *p;
606 {
607 register int i, rem;
608 register struct mbuf *md;
609 register char *fromcp, *tocp;
610 struct vnode *dp;
611 int flag;
612 int error;
613
614 flag = ndp->ni_nameiop & OPMASK;
615 MALLOC(ndp->ni_pnbuf, char *, len + 1, M_NAMEI, M_WAITOK);
616 /*
617 * Copy the name from the mbuf list to ndp->ni_pnbuf
618 * and set the various ndp fields appropriately.
619 */
620 fromcp = *dposp;
621 tocp = ndp->ni_pnbuf;
622 md = *mdp;
623 rem = mtod(md, caddr_t) + md->m_len - fromcp;
624 ndp->ni_hash = 0;
625 for (i = 0; i < len; i++) {
626 while (rem == 0) {
627 md = md->m_next;
628 if (md == NULL) {
629 error = EBADRPC;
630 goto out;
631 }
632 fromcp = mtod(md, caddr_t);
633 rem = md->m_len;
634 }
635 if (*fromcp == '\0' || *fromcp == '/') {
636 error = EINVAL;
637 goto out;
638 }
639 if (*fromcp & 0200)
640 if ((*fromcp&0377) == ('/'|0200) || flag != DELETE) {
641 error = EINVAL;
642 goto out;
643 }
644 ndp->ni_hash += (unsigned char)*fromcp;
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