xref: /csrg-svn/sys/nfs/nfs_subs.c (revision 54445)
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  * %sccs.include.redist.c%
9  *
10  *	@(#)nfs_subs.c	7.55 (Berkeley) 06/25/92
11  */
12 
13 /*
14  * These functions support the macros and help fiddle mbuf chains for
15  * the nfs op functions. They do things like create the rpc header and
16  * copy data between mbuf chains and uio lists.
17  */
18 #include <sys/param.h>
19 #include <sys/proc.h>
20 #include <sys/filedesc.h>
21 #include <sys/systm.h>
22 #include <sys/kernel.h>
23 #include <sys/mount.h>
24 #include <sys/file.h>
25 #include <sys/vnode.h>
26 #include <sys/namei.h>
27 #include <sys/mbuf.h>
28 #include <sys/map.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 
32 #include <vm/vm.h>
33 
34 #include <ufs/ufs/quota.h>
35 #include <ufs/ufs/inode.h>
36 #include <ufs/ufs/ufsmount.h>
37 
38 #include <nfs/rpcv2.h>
39 #include <nfs/nfsv2.h>
40 #include <nfs/nfsnode.h>
41 #include <nfs/nfs.h>
42 #include <nfs/xdr_subs.h>
43 #include <nfs/nfsm_subs.h>
44 #include <nfs/nfsmount.h>
45 #include <nfs/nqnfs.h>
46 #include <nfs/nfsrtt.h>
47 
48 #define TRUE	1
49 #define	FALSE	0
50 
51 /*
52  * Data items converted to xdr at startup, since they are constant
53  * This is kinda hokey, but may save a little time doing byte swaps
54  */
55 u_long nfs_procids[NFS_NPROCS];
56 u_long nfs_xdrneg1;
57 u_long rpc_call, rpc_vers, rpc_reply, rpc_msgdenied, rpc_autherr,
58 	rpc_mismatch, rpc_auth_unix, rpc_msgaccepted, rpc_rejectedcred,
59 	rpc_auth_kerb;
60 u_long nfs_vers, nfs_prog, nfs_true, nfs_false;
61 
62 /* And other global data */
63 static u_long nfs_xid = 0;
64 enum vtype ntov_type[7] = { VNON, VREG, VDIR, VBLK, VCHR, VLNK, VNON };
65 extern struct proc *nfs_iodwant[NFS_MAXASYNCDAEMON];
66 extern struct nfsreq nfsreqh;
67 extern int nqnfs_piggy[NFS_NPROCS];
68 extern struct nfsrtt nfsrtt;
69 extern union nqsrvthead nqthead;
70 extern union nqsrvthead nqfhead[NQLCHSZ];
71 extern time_t nqnfsstarttime;
72 extern u_long nqnfs_prog, nqnfs_vers;
73 extern int nqsrv_clockskew;
74 extern int nqsrv_writeslack;
75 extern int nqsrv_maxlease;
76 
77 /*
78  * Create the header for an rpc request packet
79  * The hsiz is the size of the rest of the nfs request header.
80  * (just used to decide if a cluster is a good idea)
81  */
82 struct mbuf *
83 nfsm_reqh(vp, procid, hsiz, bposp)
84 	struct vnode *vp;
85 	u_long procid;
86 	int hsiz;
87 	caddr_t *bposp;
88 {
89 	register struct mbuf *mb;
90 	register u_long *tl;
91 	register caddr_t bpos;
92 	struct mbuf *mb2;
93 	struct nfsmount *nmp;
94 	int nqflag;
95 
96 	MGET(mb, M_WAIT, MT_DATA);
97 	if (hsiz >= MINCLSIZE)
98 		MCLGET(mb, M_WAIT);
99 	mb->m_len = 0;
100 	bpos = mtod(mb, caddr_t);
101 
102 	/*
103 	 * For NQNFS, add lease request.
104 	 */
105 	if (vp) {
106 		nmp = VFSTONFS(vp->v_mount);
107 		if (nmp->nm_flag & NFSMNT_NQNFS) {
108 			nqflag = NQNFS_NEEDLEASE(vp, procid);
109 			if (nqflag) {
110 				nfsm_build(tl, u_long *, 2*NFSX_UNSIGNED);
111 				*tl++ = txdr_unsigned(nqflag);
112 				*tl = txdr_unsigned(nmp->nm_leaseterm);
113 			} else {
114 				nfsm_build(tl, u_long *, NFSX_UNSIGNED);
115 				*tl = 0;
116 			}
117 		}
118 	}
119 	/* Finally, return values */
120 	*bposp = bpos;
121 	return (mb);
122 }
123 
124 /*
125  * Build the RPC header and fill in the authorization info.
126  * The authorization string argument is only used when the credentials
127  * come from outside of the kernel.
128  * Returns the head of the mbuf list.
129  */
130 struct mbuf *
131 nfsm_rpchead(cr, nqnfs, procid, auth_type, auth_len, auth_str, mrest,
132 	mrest_len, mbp, xidp)
133 	register struct ucred *cr;
134 	int nqnfs;
135 	int procid;
136 	int auth_type;
137 	int auth_len;
138 	char *auth_str;
139 	struct mbuf *mrest;
140 	int mrest_len;
141 	struct mbuf **mbp;
142 	u_long *xidp;
143 {
144 	register struct mbuf *mb;
145 	register u_long *tl;
146 	register caddr_t bpos;
147 	register int i;
148 	struct mbuf *mreq, *mb2;
149 	int siz, grpsiz, authsiz;
150 
151 	authsiz = nfsm_rndup(auth_len);
152 	if (auth_type == RPCAUTH_NQNFS)
153 		authsiz += 2 * NFSX_UNSIGNED;
154 	MGETHDR(mb, M_WAIT, MT_DATA);
155 	if ((authsiz + 10*NFSX_UNSIGNED) >= MINCLSIZE) {
156 		MCLGET(mb, M_WAIT);
157 	} else if ((authsiz + 10*NFSX_UNSIGNED) < MHLEN) {
158 		MH_ALIGN(mb, authsiz + 10*NFSX_UNSIGNED);
159 	} else {
160 		MH_ALIGN(mb, 8*NFSX_UNSIGNED);
161 	}
162 	mb->m_len = 0;
163 	mreq = mb;
164 	bpos = mtod(mb, caddr_t);
165 
166 	/*
167 	 * First the RPC header.
168 	 */
169 	nfsm_build(tl, u_long *, 8*NFSX_UNSIGNED);
170 	if (++nfs_xid == 0)
171 		nfs_xid++;
172 	*tl++ = *xidp = txdr_unsigned(nfs_xid);
173 	*tl++ = rpc_call;
174 	*tl++ = rpc_vers;
175 	if (nqnfs) {
176 		*tl++ = txdr_unsigned(NQNFS_PROG);
177 		*tl++ = txdr_unsigned(NQNFS_VER1);
178 	} else {
179 		*tl++ = txdr_unsigned(NFS_PROG);
180 		*tl++ = txdr_unsigned(NFS_VER2);
181 	}
182 	*tl++ = txdr_unsigned(procid);
183 
184 	/*
185 	 * And then the authorization cred.
186 	 */
187 	*tl++ = txdr_unsigned(auth_type);
188 	*tl = txdr_unsigned(authsiz);
189 	switch (auth_type) {
190 	case RPCAUTH_UNIX:
191 		nfsm_build(tl, u_long *, auth_len);
192 		*tl++ = 0;		/* stamp ?? */
193 		*tl++ = 0;		/* NULL hostname */
194 		*tl++ = txdr_unsigned(cr->cr_uid);
195 		*tl++ = txdr_unsigned(cr->cr_groups[0]);
196 		grpsiz = (auth_len >> 2) - 5;
197 		*tl++ = txdr_unsigned(grpsiz);
198 		for (i = 1; i <= grpsiz; i++)
199 			*tl++ = txdr_unsigned(cr->cr_groups[i]);
200 		break;
201 	case RPCAUTH_NQNFS:
202 		nfsm_build(tl, u_long *, 2*NFSX_UNSIGNED);
203 		*tl++ = txdr_unsigned(cr->cr_uid);
204 		*tl = txdr_unsigned(auth_len);
205 		siz = auth_len;
206 		while (siz > 0) {
207 			if (M_TRAILINGSPACE(mb) == 0) {
208 				MGET(mb2, M_WAIT, MT_DATA);
209 				if (siz >= MINCLSIZE)
210 					MCLGET(mb2, M_WAIT);
211 				mb->m_next = mb2;
212 				mb = mb2;
213 				mb->m_len = 0;
214 				bpos = mtod(mb, caddr_t);
215 			}
216 			i = MIN(siz, M_TRAILINGSPACE(mb));
217 			bcopy(auth_str, bpos, i);
218 			mb->m_len += i;
219 			auth_str += i;
220 			bpos += i;
221 			siz -= i;
222 		}
223 		if ((siz = nfsm_rndup(auth_len) - auth_len) > 0) {
224 			for (i = 0; i < siz; i++)
225 				*bpos++ = '\0';
226 			mb->m_len += siz;
227 		}
228 		break;
229 	};
230 	nfsm_build(tl, u_long *, 2*NFSX_UNSIGNED);
231 	*tl++ = txdr_unsigned(RPCAUTH_NULL);
232 	*tl = 0;
233 	mb->m_next = mrest;
234 	mreq->m_pkthdr.len = authsiz + 10*NFSX_UNSIGNED + mrest_len;
235 	mreq->m_pkthdr.rcvif = (struct ifnet *)0;
236 	*mbp = mb;
237 	return (mreq);
238 }
239 
240 /*
241  * copies mbuf chain to the uio scatter/gather list
242  */
243 nfsm_mbuftouio(mrep, uiop, siz, dpos)
244 	struct mbuf **mrep;
245 	register struct uio *uiop;
246 	int siz;
247 	caddr_t *dpos;
248 {
249 	register char *mbufcp, *uiocp;
250 	register int xfer, left, len;
251 	register struct mbuf *mp;
252 	long uiosiz, rem;
253 	int error = 0;
254 
255 	mp = *mrep;
256 	mbufcp = *dpos;
257 	len = mtod(mp, caddr_t)+mp->m_len-mbufcp;
258 	rem = nfsm_rndup(siz)-siz;
259 	while (siz > 0) {
260 		if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
261 			return (EFBIG);
262 		left = uiop->uio_iov->iov_len;
263 		uiocp = uiop->uio_iov->iov_base;
264 		if (left > siz)
265 			left = siz;
266 		uiosiz = left;
267 		while (left > 0) {
268 			while (len == 0) {
269 				mp = mp->m_next;
270 				if (mp == NULL)
271 					return (EBADRPC);
272 				mbufcp = mtod(mp, caddr_t);
273 				len = mp->m_len;
274 			}
275 			xfer = (left > len) ? len : left;
276 #ifdef notdef
277 			/* Not Yet.. */
278 			if (uiop->uio_iov->iov_op != NULL)
279 				(*(uiop->uio_iov->iov_op))
280 				(mbufcp, uiocp, xfer);
281 			else
282 #endif
283 			if (uiop->uio_segflg == UIO_SYSSPACE)
284 				bcopy(mbufcp, uiocp, xfer);
285 			else
286 				copyout(mbufcp, uiocp, xfer);
287 			left -= xfer;
288 			len -= xfer;
289 			mbufcp += xfer;
290 			uiocp += xfer;
291 			uiop->uio_offset += xfer;
292 			uiop->uio_resid -= xfer;
293 		}
294 		if (uiop->uio_iov->iov_len <= siz) {
295 			uiop->uio_iovcnt--;
296 			uiop->uio_iov++;
297 		} else {
298 			uiop->uio_iov->iov_base += uiosiz;
299 			uiop->uio_iov->iov_len -= uiosiz;
300 		}
301 		siz -= uiosiz;
302 	}
303 	*dpos = mbufcp;
304 	*mrep = mp;
305 	if (rem > 0) {
306 		if (len < rem)
307 			error = nfs_adv(mrep, dpos, rem, len);
308 		else
309 			*dpos += rem;
310 	}
311 	return (error);
312 }
313 
314 /*
315  * copies a uio scatter/gather list to an mbuf chain...
316  */
317 nfsm_uiotombuf(uiop, mq, siz, bpos)
318 	register struct uio *uiop;
319 	struct mbuf **mq;
320 	int siz;
321 	caddr_t *bpos;
322 {
323 	register char *uiocp;
324 	register struct mbuf *mp, *mp2;
325 	register int xfer, left, mlen;
326 	int uiosiz, clflg, rem;
327 	char *cp;
328 
329 	if (siz > MLEN)		/* or should it >= MCLBYTES ?? */
330 		clflg = 1;
331 	else
332 		clflg = 0;
333 	rem = nfsm_rndup(siz)-siz;
334 	mp = mp2 = *mq;
335 	while (siz > 0) {
336 		if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
337 			return (EINVAL);
338 		left = uiop->uio_iov->iov_len;
339 		uiocp = uiop->uio_iov->iov_base;
340 		if (left > siz)
341 			left = siz;
342 		uiosiz = left;
343 		while (left > 0) {
344 			mlen = M_TRAILINGSPACE(mp);
345 			if (mlen == 0) {
346 				MGET(mp, M_WAIT, MT_DATA);
347 				if (clflg)
348 					MCLGET(mp, M_WAIT);
349 				mp->m_len = 0;
350 				mp2->m_next = mp;
351 				mp2 = mp;
352 				mlen = M_TRAILINGSPACE(mp);
353 			}
354 			xfer = (left > mlen) ? mlen : left;
355 #ifdef notdef
356 			/* Not Yet.. */
357 			if (uiop->uio_iov->iov_op != NULL)
358 				(*(uiop->uio_iov->iov_op))
359 				(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
360 			else
361 #endif
362 			if (uiop->uio_segflg == UIO_SYSSPACE)
363 				bcopy(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
364 			else
365 				copyin(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
366 			mp->m_len += xfer;
367 			left -= xfer;
368 			uiocp += xfer;
369 			uiop->uio_offset += xfer;
370 			uiop->uio_resid -= xfer;
371 		}
372 		if (uiop->uio_iov->iov_len <= siz) {
373 			uiop->uio_iovcnt--;
374 			uiop->uio_iov++;
375 		} else {
376 			uiop->uio_iov->iov_base += uiosiz;
377 			uiop->uio_iov->iov_len -= uiosiz;
378 		}
379 		siz -= uiosiz;
380 	}
381 	if (rem > 0) {
382 		if (rem > M_TRAILINGSPACE(mp)) {
383 			MGET(mp, M_WAIT, MT_DATA);
384 			mp->m_len = 0;
385 			mp2->m_next = mp;
386 		}
387 		cp = mtod(mp, caddr_t)+mp->m_len;
388 		for (left = 0; left < rem; left++)
389 			*cp++ = '\0';
390 		mp->m_len += rem;
391 		*bpos = cp;
392 	} else
393 		*bpos = mtod(mp, caddr_t)+mp->m_len;
394 	*mq = mp;
395 	return (0);
396 }
397 
398 /*
399  * Help break down an mbuf chain by setting the first siz bytes contiguous
400  * pointed to by returned val.
401  * If Updateflg == True we can overwrite the first part of the mbuf data
402  * (in this case it can never sleep, so it can be called from interrupt level)
403  * it may however block when Updateflg == False
404  * This is used by the macros nfsm_dissect and nfsm_dissecton for tough
405  * cases. (The macros use the vars. dpos and dpos2)
406  */
407 nfsm_disct(mdp, dposp, siz, left, updateflg, cp2)
408 	struct mbuf **mdp;
409 	caddr_t *dposp;
410 	int siz;
411 	int left;
412 	int updateflg;
413 	caddr_t *cp2;
414 {
415 	register struct mbuf *mp, *mp2;
416 	register int siz2, xfer;
417 	register caddr_t p;
418 
419 	mp = *mdp;
420 	while (left == 0) {
421 		*mdp = mp = mp->m_next;
422 		if (mp == NULL)
423 			return (EBADRPC);
424 		left = mp->m_len;
425 		*dposp = mtod(mp, caddr_t);
426 	}
427 	if (left >= siz) {
428 		*cp2 = *dposp;
429 		*dposp += siz;
430 	} else if (mp->m_next == NULL) {
431 		return (EBADRPC);
432 	} else if (siz > MHLEN) {
433 		panic("nfs S too big");
434 	} else {
435 		/* Iff update, you can overwrite, else must alloc new mbuf */
436 		if (updateflg) {
437 			NFSMINOFF(mp);
438 		} else {
439 			MGET(mp2, M_WAIT, MT_DATA);
440 			mp2->m_next = mp->m_next;
441 			mp->m_next = mp2;
442 			mp->m_len -= left;
443 			mp = mp2;
444 		}
445 		*cp2 = p = mtod(mp, caddr_t);
446 		bcopy(*dposp, p, left);		/* Copy what was left */
447 		siz2 = siz-left;
448 		p += left;
449 		mp2 = mp->m_next;
450 		/* Loop around copying up the siz2 bytes */
451 		while (siz2 > 0) {
452 			if (mp2 == NULL)
453 				return (EBADRPC);
454 			xfer = (siz2 > mp2->m_len) ? mp2->m_len : siz2;
455 			if (xfer > 0) {
456 				bcopy(mtod(mp2, caddr_t), p, xfer);
457 				NFSMADV(mp2, xfer);
458 				mp2->m_len -= xfer;
459 				p += xfer;
460 				siz2 -= xfer;
461 			}
462 			if (siz2 > 0)
463 				mp2 = mp2->m_next;
464 		}
465 		mp->m_len = siz;
466 		*mdp = mp2;
467 		*dposp = mtod(mp2, caddr_t);
468 	}
469 	return (0);
470 }
471 
472 /*
473  * Advance the position in the mbuf chain.
474  */
475 nfs_adv(mdp, dposp, offs, left)
476 	struct mbuf **mdp;
477 	caddr_t *dposp;
478 	int offs;
479 	int left;
480 {
481 	register struct mbuf *m;
482 	register int s;
483 
484 	m = *mdp;
485 	s = left;
486 	while (s < offs) {
487 		offs -= s;
488 		m = m->m_next;
489 		if (m == NULL)
490 			return (EBADRPC);
491 		s = m->m_len;
492 	}
493 	*mdp = m;
494 	*dposp = mtod(m, caddr_t)+offs;
495 	return (0);
496 }
497 
498 /*
499  * Copy a string into mbufs for the hard cases...
500  */
501 nfsm_strtmbuf(mb, bpos, cp, siz)
502 	struct mbuf **mb;
503 	char **bpos;
504 	char *cp;
505 	long siz;
506 {
507 	register struct mbuf *m1, *m2;
508 	long left, xfer, len, tlen;
509 	u_long *tl;
510 	int putsize;
511 
512 	putsize = 1;
513 	m2 = *mb;
514 	left = M_TRAILINGSPACE(m2);
515 	if (left > 0) {
516 		tl = ((u_long *)(*bpos));
517 		*tl++ = txdr_unsigned(siz);
518 		putsize = 0;
519 		left -= NFSX_UNSIGNED;
520 		m2->m_len += NFSX_UNSIGNED;
521 		if (left > 0) {
522 			bcopy(cp, (caddr_t) tl, left);
523 			siz -= left;
524 			cp += left;
525 			m2->m_len += left;
526 			left = 0;
527 		}
528 	}
529 	/* Loop around adding mbufs */
530 	while (siz > 0) {
531 		MGET(m1, M_WAIT, MT_DATA);
532 		if (siz > MLEN)
533 			MCLGET(m1, M_WAIT);
534 		m1->m_len = NFSMSIZ(m1);
535 		m2->m_next = m1;
536 		m2 = m1;
537 		tl = mtod(m1, u_long *);
538 		tlen = 0;
539 		if (putsize) {
540 			*tl++ = txdr_unsigned(siz);
541 			m1->m_len -= NFSX_UNSIGNED;
542 			tlen = NFSX_UNSIGNED;
543 			putsize = 0;
544 		}
545 		if (siz < m1->m_len) {
546 			len = nfsm_rndup(siz);
547 			xfer = siz;
548 			if (xfer < len)
549 				*(tl+(xfer>>2)) = 0;
550 		} else {
551 			xfer = len = m1->m_len;
552 		}
553 		bcopy(cp, (caddr_t) tl, xfer);
554 		m1->m_len = len+tlen;
555 		siz -= xfer;
556 		cp += xfer;
557 	}
558 	*mb = m1;
559 	*bpos = mtod(m1, caddr_t)+m1->m_len;
560 	return (0);
561 }
562 
563 /*
564  * Called once to initialize data structures...
565  */
566 nfs_init()
567 {
568 	register int i;
569 	union nqsrvthead *lhp;
570 
571 	nfsrtt.pos = 0;
572 	rpc_vers = txdr_unsigned(RPC_VER2);
573 	rpc_call = txdr_unsigned(RPC_CALL);
574 	rpc_reply = txdr_unsigned(RPC_REPLY);
575 	rpc_msgdenied = txdr_unsigned(RPC_MSGDENIED);
576 	rpc_msgaccepted = txdr_unsigned(RPC_MSGACCEPTED);
577 	rpc_mismatch = txdr_unsigned(RPC_MISMATCH);
578 	rpc_autherr = txdr_unsigned(RPC_AUTHERR);
579 	rpc_rejectedcred = txdr_unsigned(AUTH_REJECTCRED);
580 	rpc_auth_unix = txdr_unsigned(RPCAUTH_UNIX);
581 	rpc_auth_kerb = txdr_unsigned(RPCAUTH_NQNFS);
582 	nfs_vers = txdr_unsigned(NFS_VER2);
583 	nfs_prog = txdr_unsigned(NFS_PROG);
584 	nfs_true = txdr_unsigned(TRUE);
585 	nfs_false = txdr_unsigned(FALSE);
586 	/* Loop thru nfs procids */
587 	for (i = 0; i < NFS_NPROCS; i++)
588 		nfs_procids[i] = txdr_unsigned(i);
589 	/* Ensure async daemons disabled */
590 	for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
591 		nfs_iodwant[i] = (struct proc *)0;
592 	nfs_xdrneg1 = txdr_unsigned(-1);
593 	nfs_nhinit();			/* Init the nfsnode table */
594 	nfsrv_init(0);			/* Init server data structures */
595 	nfsrv_initcache();		/* Init the server request cache */
596 
597 	/*
598 	 * Initialize the nqnfs server stuff.
599 	 */
600 	if (nqnfsstarttime == 0) {
601 		nqnfsstarttime = boottime.tv_sec + nqsrv_maxlease
602 			+ nqsrv_clockskew + nqsrv_writeslack;
603 		NQLOADNOVRAM(nqnfsstarttime);
604 		nqnfs_prog = txdr_unsigned(NQNFS_PROG);
605 		nqnfs_vers = txdr_unsigned(NQNFS_VER1);
606 		nqthead.th_head[0] = &nqthead;
607 		nqthead.th_head[1] = &nqthead;
608 		for (i = 0; i < NQLCHSZ; i++) {
609 			lhp = &nqfhead[i];
610 			lhp->th_head[0] = lhp;
611 			lhp->th_head[1] = lhp;
612 		}
613 	}
614 
615 	/*
616 	 * Initialize reply list and start timer
617 	 */
618 	nfsreqh.r_prev = nfsreqh.r_next = &nfsreqh;
619 	nfs_timer();
620 }
621 
622 /*
623  * Attribute cache routines.
624  * nfs_loadattrcache() - loads or updates the cache contents from attributes
625  *	that are on the mbuf list
626  * nfs_getattrcache() - returns valid attributes if found in cache, returns
627  *	error otherwise
628  */
629 
630 /*
631  * Load the attribute cache (that lives in the nfsnode entry) with
632  * the values on the mbuf list and
633  * Iff vap not NULL
634  *    copy the attributes to *vaper
635  */
636 nfs_loadattrcache(vpp, mdp, dposp, vaper)
637 	struct vnode **vpp;
638 	struct mbuf **mdp;
639 	caddr_t *dposp;
640 	struct vattr *vaper;
641 {
642 	register struct vnode *vp = *vpp;
643 	register struct vattr *vap;
644 	register struct nfsv2_fattr *fp;
645 	extern int (**spec_nfsv2nodeop_p)();
646 	extern int (**spec_vnodeop_p)();
647 	register struct nfsnode *np;
648 	register long t1;
649 	caddr_t dpos, cp2;
650 	int error = 0;
651 	struct mbuf *md;
652 	enum vtype vtyp;
653 	u_short vmode;
654 	long rdev;
655 	struct timeval mtime;
656 	struct vnode *nvp;
657 
658 	md = *mdp;
659 	dpos = *dposp;
660 	t1 = (mtod(md, caddr_t) + md->m_len) - dpos;
661 	if (error = nfsm_disct(&md, &dpos, NFSX_FATTR, t1, TRUE, &cp2))
662 		return (error);
663 	fp = (struct nfsv2_fattr *)cp2;
664 	vtyp = nfstov_type(fp->fa_type);
665 	vmode = fxdr_unsigned(u_short, fp->fa_mode);
666 	if (vtyp == VNON || vtyp == VREG)
667 		vtyp = IFTOVT(vmode);
668 	rdev = fxdr_unsigned(long, fp->fa_rdev);
669 	fxdr_time(&fp->fa_mtime, &mtime);
670 	/*
671 	 * If v_type == VNON it is a new node, so fill in the v_type,
672 	 * n_mtime fields. Check to see if it represents a special
673 	 * device, and if so, check for a possible alias. Once the
674 	 * correct vnode has been obtained, fill in the rest of the
675 	 * information.
676 	 */
677 	np = VTONFS(vp);
678 	if (vp->v_type == VNON) {
679 		if (vtyp == VCHR && rdev == 0xffffffff)
680 			vp->v_type = vtyp = VFIFO;
681 		else
682 			vp->v_type = vtyp;
683 		if (vp->v_type == VFIFO) {
684 #ifdef FIFO
685 			extern int (**fifo_nfsv2nodeop_p)();
686 			vp->v_op = fifo_nfsv2nodeop_p;
687 #else
688 			return (EOPNOTSUPP);
689 #endif /* FIFO */
690 		}
691 		if (vp->v_type == VCHR || vp->v_type == VBLK) {
692 			vp->v_op = spec_nfsv2nodeop_p;
693 			if (nvp = checkalias(vp, (dev_t)rdev, vp->v_mount)) {
694 				/*
695 				 * Discard unneeded vnode, but save its nfsnode.
696 				 */
697 				remque(np);
698 				nvp->v_data = vp->v_data;
699 				vp->v_data = NULL;
700 				vp->v_op = spec_vnodeop_p;
701 				vrele(vp);
702 				vgone(vp);
703 				/*
704 				 * Reinitialize aliased node.
705 				 */
706 				np->n_vnode = nvp;
707 				insque(np, nfs_hash(&np->n_fh));
708 				*vpp = vp = nvp;
709 			}
710 		}
711 		if ((VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NQNFS) == 0)
712 			np->n_mtime = mtime.tv_sec;
713 	}
714 	vap = &np->n_vattr;
715 	vap->va_type = vtyp;
716 	vap->va_mode = (vmode & 07777);
717 	vap->va_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
718 	vap->va_uid = fxdr_unsigned(uid_t, fp->fa_uid);
719 	vap->va_gid = fxdr_unsigned(gid_t, fp->fa_gid);
720 	vap->va_size = fxdr_unsigned(u_long, fp->fa_size);
721 	if ((np->n_flag & NMODIFIED) == 0 || vap->va_size > np->n_size) {
722 		np->n_size = vap->va_size;
723 		vnode_pager_setsize(vp, (u_long)np->n_size);
724 	}
725 	vap->va_blocksize = fxdr_unsigned(long, fp->fa_blocksize);
726 	vap->va_rdev = (dev_t)rdev;
727 	vap->va_bytes = fxdr_unsigned(long, fp->fa_blocks) * NFS_FABLKSIZE;
728 	vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
729 	vap->va_fileid = fxdr_unsigned(long, fp->fa_fileid);
730 	vap->va_atime.ts_sec = fxdr_unsigned(long, fp->fa_atime.tv_sec);
731 	vap->va_atime.ts_nsec = 0;
732 	vap->va_flags = fxdr_unsigned(u_long, fp->fa_atime.tv_usec);
733 	vap->va_mtime.ts_sec = mtime.tv_sec;
734 	vap->va_mtime.ts_nsec = mtime.tv_usec * 1000;
735 	vap->va_ctime.ts_sec = fxdr_unsigned(long, fp->fa_ctime.tv_sec);
736 	vap->va_ctime.ts_nsec = 0;
737 	vap->va_gen = fxdr_unsigned(u_long, fp->fa_ctime.tv_usec);
738 	np->n_attrstamp = time.tv_sec;
739 	*dposp = dpos;
740 	*mdp = md;
741 	if (vaper != NULL) {
742 		bcopy((caddr_t)vap, (caddr_t)vaper, sizeof(*vap));
743 		if ((np->n_flag & NMODIFIED) && (np->n_size > vap->va_size))
744 			vaper->va_size = np->n_size;
745 		if (np->n_flag & NCHG) {
746 			if (np->n_flag & NACC) {
747 				vaper->va_atime.ts_sec = np->n_atim.tv_sec;
748 				vaper->va_atime.ts_nsec =
749 				    np->n_atim.tv_usec * 1000;
750 			}
751 			if (np->n_flag & NUPD) {
752 				vaper->va_mtime.ts_sec = np->n_mtim.tv_sec;
753 				vaper->va_mtime.ts_nsec =
754 				    np->n_mtim.tv_usec * 1000;
755 			}
756 		}
757 	}
758 	return (0);
759 }
760 
761 /*
762  * Check the time stamp
763  * If the cache is valid, copy contents to *vap and return 0
764  * otherwise return an error
765  */
766 nfs_getattrcache(vp, vap)
767 	register struct vnode *vp;
768 	struct vattr *vap;
769 {
770 	register struct nfsnode *np;
771 
772 	np = VTONFS(vp);
773 	if (VFSTONFS(vp->v_mount)->nm_flag & NFSMNT_NQNFS) {
774 		if (!NQNFS_CKCACHABLE(vp, NQL_READ) || np->n_attrstamp == 0) {
775 			nfsstats.attrcache_misses++;
776 			return (ENOENT);
777 		}
778 	} else if ((time.tv_sec - np->n_attrstamp) >= NFS_ATTRTIMEO) {
779 		nfsstats.attrcache_misses++;
780 		return (ENOENT);
781 	}
782 	nfsstats.attrcache_hits++;
783 	bcopy((caddr_t)&np->n_vattr,(caddr_t)vap,sizeof(struct vattr));
784 	if ((np->n_flag & NMODIFIED) == 0) {
785 		np->n_size = vap->va_size;
786 		vnode_pager_setsize(vp, (u_long)np->n_size);
787 	} else if (np->n_size > vap->va_size)
788 		vap->va_size = np->n_size;
789 	if (np->n_flag & NCHG) {
790 		if (np->n_flag & NACC) {
791 			vap->va_atime.ts_sec = np->n_atim.tv_sec;
792 			vap->va_atime.ts_nsec = np->n_atim.tv_usec * 1000;
793 		}
794 		if (np->n_flag & NUPD) {
795 			vap->va_mtime.ts_sec = np->n_mtim.tv_sec;
796 			vap->va_mtime.ts_nsec = np->n_mtim.tv_usec * 1000;
797 		}
798 	}
799 	return (0);
800 }
801 
802 /*
803  * Set up nameidata for a lookup() call and do it
804  */
805 nfs_namei(ndp, fhp, len, slp, nam, mdp, dposp, p)
806 	register struct nameidata *ndp;
807 	fhandle_t *fhp;
808 	int len;
809 	struct nfssvc_sock *slp;
810 	struct mbuf *nam;
811 	struct mbuf **mdp;
812 	caddr_t *dposp;
813 	struct proc *p;
814 {
815 	register int i, rem;
816 	register struct mbuf *md;
817 	register char *fromcp, *tocp;
818 	struct vnode *dp;
819 	int error, rdonly;
820 	struct componentname *cnp = &ndp->ni_cnd;
821 
822 	MALLOC(cnp->cn_pnbuf, char *, len + 1, M_NAMEI, M_WAITOK);
823 	/*
824 	 * Copy the name from the mbuf list to ndp->ni_pnbuf
825 	 * and set the various ndp fields appropriately.
826 	 */
827 	fromcp = *dposp;
828 	tocp = cnp->cn_pnbuf;
829 	md = *mdp;
830 	rem = mtod(md, caddr_t) + md->m_len - fromcp;
831 	cnp->cn_hash = 0;
832 	for (i = 0; i < len; i++) {
833 		while (rem == 0) {
834 			md = md->m_next;
835 			if (md == NULL) {
836 				error = EBADRPC;
837 				goto out;
838 			}
839 			fromcp = mtod(md, caddr_t);
840 			rem = md->m_len;
841 		}
842 		if (*fromcp == '\0' || *fromcp == '/') {
843 			error = EINVAL;
844 			goto out;
845 		}
846 		if (*fromcp & 0200)
847 			if ((*fromcp&0377) == ('/'|0200) || cnp->cn_nameiop != DELETE) {
848 				error = EINVAL;
849 				goto out;
850 			}
851 		cnp->cn_hash += (unsigned char)*fromcp;
852 		*tocp++ = *fromcp++;
853 		rem--;
854 	}
855 	*tocp = '\0';
856 	*mdp = md;
857 	*dposp = fromcp;
858 	len = nfsm_rndup(len)-len;
859 	if (len > 0) {
860 		if (rem >= len)
861 			*dposp += len;
862 		else if (error = nfs_adv(mdp, dposp, len, rem))
863 			goto out;
864 	}
865 	ndp->ni_pathlen = tocp - cnp->cn_pnbuf;
866 	cnp->cn_nameptr = cnp->cn_pnbuf;
867 	/*
868 	 * Extract and set starting directory.
869 	 */
870 	if (error = nfsrv_fhtovp(fhp, FALSE, &dp, ndp->ni_cnd.cn_cred, slp,
871 	    nam, &rdonly))
872 		goto out;
873 	if (dp->v_type != VDIR) {
874 		vrele(dp);
875 		error = ENOTDIR;
876 		goto out;
877 	}
878 	ndp->ni_startdir = dp;
879 	if (rdonly)
880 		cnp->cn_flags |= (NOCROSSMOUNT | RDONLY);
881 	else
882 		cnp->cn_flags |= NOCROSSMOUNT;
883 	/*
884 	 * And call lookup() to do the real work
885 	 */
886 	cnp->cn_proc = p;
887 	if (error = lookup(ndp))
888 		goto out;
889 	/*
890 	 * Check for encountering a symbolic link
891 	 */
892 	if (cnp->cn_flags & ISSYMLINK) {
893 		if ((cnp->cn_flags & LOCKPARENT) && ndp->ni_pathlen == 1)
894 			vput(ndp->ni_dvp);
895 		else
896 			vrele(ndp->ni_dvp);
897 		vput(ndp->ni_vp);
898 		ndp->ni_vp = NULL;
899 		error = EINVAL;
900 		goto out;
901 	}
902 	/*
903 	 * Check for saved name request
904 	 */
905 	if (cnp->cn_flags & (SAVENAME | SAVESTART)) {
906 		cnp->cn_flags |= HASBUF;
907 		return (0);
908 	}
909 out:
910 	FREE(cnp->cn_pnbuf, M_NAMEI);
911 	return (error);
912 }
913 
914 /*
915  * A fiddled version of m_adj() that ensures null fill to a long
916  * boundary and only trims off the back end
917  */
918 void
919 nfsm_adj(mp, len, nul)
920 	struct mbuf *mp;
921 	register int len;
922 	int nul;
923 {
924 	register struct mbuf *m;
925 	register int count, i;
926 	register char *cp;
927 
928 	/*
929 	 * Trim from tail.  Scan the mbuf chain,
930 	 * calculating its length and finding the last mbuf.
931 	 * If the adjustment only affects this mbuf, then just
932 	 * adjust and return.  Otherwise, rescan and truncate
933 	 * after the remaining size.
934 	 */
935 	count = 0;
936 	m = mp;
937 	for (;;) {
938 		count += m->m_len;
939 		if (m->m_next == (struct mbuf *)0)
940 			break;
941 		m = m->m_next;
942 	}
943 	if (m->m_len > len) {
944 		m->m_len -= len;
945 		if (nul > 0) {
946 			cp = mtod(m, caddr_t)+m->m_len-nul;
947 			for (i = 0; i < nul; i++)
948 				*cp++ = '\0';
949 		}
950 		return;
951 	}
952 	count -= len;
953 	if (count < 0)
954 		count = 0;
955 	/*
956 	 * Correct length for chain is "count".
957 	 * Find the mbuf with last data, adjust its length,
958 	 * and toss data from remaining mbufs on chain.
959 	 */
960 	for (m = mp; m; m = m->m_next) {
961 		if (m->m_len >= count) {
962 			m->m_len = count;
963 			if (nul > 0) {
964 				cp = mtod(m, caddr_t)+m->m_len-nul;
965 				for (i = 0; i < nul; i++)
966 					*cp++ = '\0';
967 			}
968 			break;
969 		}
970 		count -= m->m_len;
971 	}
972 	while (m = m->m_next)
973 		m->m_len = 0;
974 }
975 
976 /*
977  * nfsrv_fhtovp() - convert a fh to a vnode ptr (optionally locked)
978  * 	- look up fsid in mount list (if not found ret error)
979  *	- check that it is exported
980  *	- get vp by calling VFS_FHTOVP() macro
981  *	- if not lockflag unlock it with VOP_UNLOCK()
982  *	- if cred->cr_uid == 0 or MNT_EXPORTANON set it to neth_anon
983  */
984 nfsrv_fhtovp(fhp, lockflag, vpp, cred, slp, nam, rdonlyp)
985 	fhandle_t *fhp;
986 	int lockflag;
987 	struct vnode **vpp;
988 	struct ucred *cred;
989 	struct nfssvc_sock *slp;
990 	struct mbuf *nam;
991 	int *rdonlyp;
992 {
993 	USES_VOP_UNLOCK;
994 	register struct mount *mp;
995 	register struct netaddrhash *np;
996 	register struct ufsmount *ump;
997 	register struct nfsuid *uidp;
998 	struct sockaddr *saddr;
999 	int error;
1000 
1001 	*vpp = (struct vnode *)0;
1002 	if ((mp = getvfs(&fhp->fh_fsid)) == NULL)
1003 		return (ESTALE);
1004 	if ((mp->mnt_flag & MNT_EXPORTED) == 0)
1005 		return (EACCES);
1006 
1007 	/*
1008 	 * Get the export permission structure for this <mp, client> tuple.
1009 	 */
1010 	ump = VFSTOUFS(mp);
1011 	if (nam) {
1012 
1013 		/*
1014 		 * First search for a network match.
1015 		 */
1016 		np = ump->um_netaddr[NETMASK_HASH];
1017 		while (np) {
1018 		    if (nfs_netaddr_match(np->neth_family, &np->neth_haddr,
1019 			&np->neth_hmask, nam))
1020 			break;
1021 			np = np->neth_next;
1022 		}
1023 
1024 		/*
1025 		 * If not found, try for an address match.
1026 		 */
1027 		if (np == (struct netaddrhash *)0) {
1028 		    saddr = mtod(nam, struct sockaddr *);
1029 		    np = ump->um_netaddr[NETADDRHASH(saddr)];
1030 		    while (np) {
1031 			if (nfs_netaddr_match(np->neth_family, &np->neth_haddr,
1032 			    (struct netaddrhash *)0, nam))
1033 			    break;
1034 			np = np->neth_next;
1035 		    }
1036 		}
1037 	} else
1038 		np = (struct netaddrhash *)0;
1039 	if (np == (struct netaddrhash *)0) {
1040 
1041 		/*
1042 		 * If no address match, use the default if it exists.
1043 		 */
1044 		if ((mp->mnt_flag & MNT_DEFEXPORTED) == 0)
1045 			return (EACCES);
1046 		np = &ump->um_defexported;
1047 	}
1048 
1049 	/*
1050 	 * Check/setup credentials.
1051 	 */
1052 	if (np->neth_exflags & MNT_EXKERB) {
1053 		uidp = slp->ns_uidh[NUIDHASH(cred->cr_uid)];
1054 		while (uidp) {
1055 			if (uidp->nu_uid == cred->cr_uid)
1056 				break;
1057 			uidp = uidp->nu_hnext;
1058 		}
1059 		if (uidp) {
1060 			if (cred->cr_ref != 1)
1061 				panic("nsrv fhtovp");
1062 			*cred = uidp->nu_cr;
1063 		} else
1064 			return (NQNFS_AUTHERR);
1065 	} else if (cred->cr_uid == 0 || (np->neth_exflags & MNT_EXPORTANON))
1066 		*cred = np->neth_anon;
1067 	if (error = VFS_FHTOVP(mp, &fhp->fh_fid, vpp))
1068 		return (ESTALE);
1069 	if (np->neth_exflags & MNT_EXRDONLY)
1070 		*rdonlyp = 1;
1071 	else
1072 		*rdonlyp = 0;
1073 	if (!lockflag)
1074 		VOP_UNLOCK(*vpp);
1075 	return (0);
1076 }
1077