xref: /netbsd-src/usr.sbin/puffs/mount_9p/node.c (revision e6c7e151de239c49d2e38720a061ed9d1fa99309)
1 /*	$NetBSD: node.c,v 1.23 2019/06/07 05:34:34 ozaki-r Exp $	*/
2 
3 /*
4  * Copyright (c) 2007  Antti Kantee.  All Rights Reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 #ifndef lint
30 __RCSID("$NetBSD: node.c,v 1.23 2019/06/07 05:34:34 ozaki-r Exp $");
31 #endif /* !lint */
32 
33 #include <assert.h>
34 #include <errno.h>
35 #include <puffs.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 
39 #include "ninepuffs.h"
40 #include "nineproto.h"
41 
42 static void *
43 nodecmp(struct puffs_usermount *pu, struct puffs_node *pn, void *arg)
44 {
45 	struct vattr *vap = &pn->pn_va;
46 	struct qid9p *qid = arg;
47 
48 	if (vap->va_fileid == qid->qidpath && vap->va_gen == qid->qidvers)
49 		return pn;
50 
51 	return NULL;
52 }
53 
54 static int
55 do_getattr(struct puffs_usermount *pu, struct puffs_node *pn, struct vattr *vap)
56 {
57 	AUTOVAR(pu);
58 	struct p9pnode *p9n = pn->pn_data;
59 
60 	p9pbuf_put_1(pb, P9PROTO_T_STAT);
61 	p9pbuf_put_2(pb, tag);
62 	p9pbuf_put_4(pb, p9n->fid_base);
63 	GETRESPONSE(pb);
64 
65 	if (p9pbuf_get_type(pb) != P9PROTO_R_STAT) {
66 		rv = proto_handle_rerror(pu, pb);
67 		goto out;
68 	}
69 	rv = proto_expect_stat(pu, pb, vap);
70 
71  out:
72 	RETURN(rv);
73 }
74 
75 int
76 puffs9p_node_getattr(struct puffs_usermount *pu, void *opc, struct vattr *vap,
77 	const struct puffs_cred *pcr)
78 {
79 	struct puffs_node *pn = opc;
80 	int rv;
81 
82 	rv = do_getattr(pu, pn, &pn->pn_va);
83 	if (rv == 0)
84 		memcpy(vap, &pn->pn_va, sizeof(struct vattr));
85 	return rv;
86 }
87 
88 int
89 puffs9p_node_lookup(struct puffs_usermount *pu, void *opc, struct puffs_newinfo *pni,
90 	const struct puffs_cn *pcn)
91 {
92 	AUTOVAR(pu);
93 	struct vattr va;
94 	struct puffs_node *pn, *pn_dir = opc;
95 	struct p9pnode *p9n_dir = pn_dir->pn_data;
96 	p9ptag_t tfid = NEXTFID(p9p);
97 	struct qid9p newqid;
98 	uint16_t nqid;
99 
100 	p9pbuf_put_1(pb, P9PROTO_T_WALK);
101 	p9pbuf_put_2(pb, tag);
102 	p9pbuf_put_4(pb, p9n_dir->fid_base);
103 	p9pbuf_put_4(pb, tfid);
104 	p9pbuf_put_2(pb, 1);
105 	p9pbuf_put_str(pb, pcn->pcn_name);
106 	GETRESPONSE(pb);
107 
108 	rv = proto_expect_walk_nqids(pu, pb, &nqid);
109 	if (rv) {
110 		rv = ENOENT;
111 		goto out;
112 	}
113 	if (nqid != 1) {
114 		rv = EPROTO;
115 		goto out;
116 	}
117 	if ((rv = proto_getqid(pb, &newqid)))
118 		goto out;
119 
120 	/* we get the parent vers in walk(?)  compensate */
121 	p9pbuf_recycleout(pb);
122 	tag = NEXTTAG(p9p);
123 	p9pbuf_put_1(pb, P9PROTO_T_STAT);
124 	p9pbuf_put_2(pb, tag);
125 	p9pbuf_put_4(pb, tfid);
126 	GETRESPONSE(pb);
127 	if ((rv = proto_expect_stat(pu, pb, &va)) != 0) {
128 		proto_cc_clunkfid(pu, tfid, 0);
129 		rv = ENOENT;
130 		goto out;
131 	}
132 	if (newqid.qidpath != va.va_fileid) {
133 		proto_cc_clunkfid(pu, tfid, 0);
134 		rv = EPROTO;
135 		goto out;
136 	}
137 	newqid.qidvers = va.va_gen;
138 
139 	pn = puffs_pn_nodewalk(pu, nodecmp, &newqid);
140 	if (pn == NULL)
141 		pn = newp9pnode_qid(pu, &newqid, tfid);
142 	else
143 		proto_cc_clunkfid(pu, tfid, 0);
144 	/* assert pn */
145 	memcpy(&pn->pn_va, &va, sizeof(va));
146 
147 	puffs_newinfo_setcookie(pni, pn);
148 	puffs_newinfo_setvtype(pni, pn->pn_va.va_type);
149 	puffs_newinfo_setsize(pni, pn->pn_va.va_size);
150 	puffs_newinfo_setrdev(pni, pn->pn_va.va_rdev);
151 
152  out:
153 	RETURN(rv);
154 }
155 
156 /*
157  * Problem is that 9P doesn't allow seeking into a directory.  So we
158  * maintain a list of active fids for any given directory.  They
159  * start living at the first read and exist either until the directory
160  * is closed or until they reach the end.
161  */
162 int
163 puffs9p_node_readdir(struct puffs_usermount *pu, void *opc, struct dirent *dent,
164 	off_t *readoff, size_t *reslen, const struct puffs_cred *pcr,
165 	int *eofflag, off_t *cookies, size_t *ncookies)
166 {
167 	AUTOVAR(pu);
168 	struct puffs_node *pn = opc;
169 	struct p9pnode *p9n = pn->pn_data;
170 	struct vattr va;
171 	struct dirfid *dfp;
172 	char *name;
173 	uint32_t count;
174 	uint16_t statsize;
175 
176 	rv = getdfwithoffset(pu, p9n, *readoff, &dfp);
177 	if (rv)
178 		goto out;
179 
180 	tag = NEXTTAG(p9p);
181 	p9pbuf_put_1(pb, P9PROTO_T_READ);
182 	p9pbuf_put_2(pb, tag);
183 	p9pbuf_put_4(pb, dfp->fid);
184 	p9pbuf_put_8(pb, *readoff);
185 	p9pbuf_put_4(pb, *reslen); /* XXX */
186 	GETRESPONSE(pb);
187 
188 	p9pbuf_get_4(pb, &count);
189 
190 	/*
191 	 * if count is 0, assume we at end-of-dir.  dfp is no longer
192 	 * useful, so nuke it
193 	 */
194 	if (count == 0) {
195 		*eofflag = 1;
196 		releasedf(pu, dfp);
197 		goto out;
198 	}
199 
200 	while (count > 0) {
201 		if ((rv = proto_getstat(pu, pb, &va, &name, &statsize))) {
202 			/*
203 			 * If there was an error, it's unlikely we'll be
204 			 * coming back, so just nuke the dfp.  If we do
205 			 * come back for some strange reason, we'll just
206 			 * regen it.
207 			 */
208 			releasedf(pu, dfp);
209 			goto out;
210 		}
211 
212 		puffs_nextdent(&dent, name, va.va_fileid,
213 		    puffs_vtype2dt(va.va_type), reslen);
214 
215 		count -= statsize;
216 		*readoff += statsize;
217 		dfp->seekoff += statsize;
218 		free(name);
219 	}
220 
221 	storedf(p9n, dfp);
222 
223  out:
224 	RETURN(rv);
225 }
226 
227 int
228 puffs9p_node_setattr(struct puffs_usermount *pu, void *opc,
229 	const struct vattr *va, const struct puffs_cred *pcr)
230 {
231 	AUTOVAR(pu);
232 	struct puffs_node *pn = opc;
233 	struct p9pnode *p9n = pn->pn_data;
234 
235 	p9pbuf_put_1(pb, P9PROTO_T_WSTAT);
236 	p9pbuf_put_2(pb, tag);
237 	p9pbuf_put_4(pb, p9n->fid_base);
238 	proto_make_stat(pu, pb, va, NULL, pn->pn_va.va_type);
239 	GETRESPONSE(pb);
240 
241 	if (p9pbuf_get_type(pb) != P9PROTO_R_WSTAT) {
242 		rv = proto_handle_rerror(pu, pb);
243 	}
244 
245  out:
246 	RETURN(rv);
247 }
248 
249 /*
250  * Ok, time to get clever.  There are two possible cases: we are
251  * opening a file or we are opening a directory.
252  *
253  * If it's a directory, don't bother opening it here, but rather
254  * wait until readdir, since it's probable we need to be able to
255  * open a directory there in any case.
256  *
257  * If it's a regular file, open it here with whatever credentials
258  * we happen to have.   Let the upper layers of the kernel worry
259  * about permission control.
260  */
261 int
262 puffs9p_node_open(struct puffs_usermount *pu, void *opc, int mode,
263 	const struct puffs_cred *pcr)
264 {
265 	struct puffs_cc *pcc = puffs_cc_getcc(pu);
266 	struct puffs9p *p9p = puffs_getspecific(pu);
267 	struct puffs_node *pn = opc;
268 	struct p9pnode *p9n = pn->pn_data;
269 	p9pfid_t nfid;
270 	int error = 0;
271 
272 	puffs_setback(pcc, PUFFS_SETBACK_INACT_N1);
273 	if (pn->pn_va.va_type != VDIR) {
274 		if (mode & FREAD && p9n->fid_read == P9P_INVALFID) {
275 			nfid = NEXTFID(p9p);
276 			error = proto_cc_open(pu, p9n->fid_base, nfid,
277 			    P9PROTO_OMODE_READ);
278 			if (error)
279 				return error;
280 			p9n->fid_read = nfid;
281 		}
282 		if (mode & FWRITE && p9n->fid_write == P9P_INVALFID) {
283 			nfid = NEXTFID(p9p);
284 			error = proto_cc_open(pu, p9n->fid_base, nfid,
285 			    P9PROTO_OMODE_WRITE);
286 			if (error)
287 				return error;
288 			p9n->fid_write = nfid;
289 		}
290 	}
291 
292 	return 0;
293 }
294 
295 int
296 puffs9p_node_inactive(struct puffs_usermount *pu, void *opc)
297 {
298 	struct puffs_node *pn = opc;
299 	struct p9pnode *p9n = pn->pn_data;
300 
301 	if (pn->pn_va.va_type == VDIR) {
302 		nukealldf(pu, p9n);
303 	} else  {
304 		if (p9n->fid_read != P9P_INVALFID) {
305 			proto_cc_clunkfid(pu, p9n->fid_read, 0);
306 			p9n->fid_read = P9P_INVALFID;
307 		}
308 		if (p9n->fid_write != P9P_INVALFID) {
309 			proto_cc_clunkfid(pu, p9n->fid_write, 0);
310 			p9n->fid_write = P9P_INVALFID;
311 		}
312 	}
313 
314 	return 0;
315 }
316 
317 int
318 puffs9p_node_read(struct puffs_usermount *pu, void *opc, uint8_t *buf,
319 	off_t offset, size_t *resid, const struct puffs_cred *pcr,
320 	int ioflag)
321 {
322 	AUTOVAR(pu);
323 	struct puffs_node *pn = opc;
324 	struct p9pnode *p9n = pn->pn_data;
325 	uint32_t count;
326 	size_t nread;
327 
328 	nread = 0;
329 	while (*resid > 0 && (uint64_t)(offset+nread) < pn->pn_va.va_size) {
330 		p9pbuf_put_1(pb, P9PROTO_T_READ);
331 		p9pbuf_put_2(pb, tag);
332 		p9pbuf_put_4(pb, p9n->fid_read);
333 		p9pbuf_put_8(pb, offset+nread);
334 		p9pbuf_put_4(pb, MIN((uint32_t)*resid,p9p->maxreq-24));
335 		GETRESPONSE(pb);
336 
337 		if (p9pbuf_get_type(pb) != P9PROTO_R_READ) {
338 			rv = proto_handle_rerror(pu, pb);
339 			break;
340 		}
341 
342 		p9pbuf_get_4(pb, &count);
343 		if ((rv = p9pbuf_read_data(pb, buf + nread, count)))
344 			break;
345 
346 		if (count == 0)
347 			break;
348 
349 		*resid -= count;
350 		nread += count;
351 
352 		p9pbuf_recycleout(pb);
353 	}
354 
355  out:
356 	RETURN(rv);
357 }
358 
359 int
360 puffs9p_node_write(struct puffs_usermount *pu, void *opc, uint8_t *buf,
361 	off_t offset, size_t *resid, const struct puffs_cred *cred,
362 	int ioflag)
363 {
364 	AUTOVAR(pu);
365 	struct puffs_node *pn = opc;
366 	struct p9pnode *p9n = pn->pn_data;
367 	uint32_t chunk, count;
368 	size_t nwrite;
369 
370 	if (ioflag & PUFFS_IO_APPEND)
371 		offset = pn->pn_va.va_size;
372 
373 	nwrite = 0;
374 	while (*resid > 0) {
375 		chunk = MIN(*resid, p9p->maxreq-32);
376 
377 		p9pbuf_put_1(pb, P9PROTO_T_WRITE);
378 		p9pbuf_put_2(pb, tag);
379 		p9pbuf_put_4(pb, p9n->fid_write);
380 		p9pbuf_put_8(pb, offset+nwrite);
381 		p9pbuf_put_4(pb, chunk);
382 		p9pbuf_write_data(pb, buf+nwrite, chunk);
383 		GETRESPONSE(pb);
384 
385 		if (p9pbuf_get_type(pb) != P9PROTO_R_WRITE) {
386 			rv = proto_handle_rerror(pu, pb);
387 			break;
388 		}
389 
390 		p9pbuf_get_4(pb, &count);
391 		*resid -= count;
392 		nwrite += count;
393 
394 		if (count != chunk) {
395 			rv = EPROTO;
396 			break;
397 		}
398 
399 		p9pbuf_recycleout(pb);
400 	}
401 
402  out:
403 	RETURN(rv);
404 }
405 
406 static int
407 nodecreate(struct puffs_usermount *pu, struct puffs_node *pn,
408 	struct puffs_newinfo *pni, const char *name,
409 	const struct vattr *vap, uint32_t dirbit)
410 {
411 	AUTOVAR(pu);
412 	struct puffs_node *pn_new;
413 	struct p9pnode *p9n = pn->pn_data;
414 	p9pfid_t nfid = NEXTFID(p9p);
415 	struct qid9p nqid;
416 	int tries = 0;
417 
418  again:
419 	if (++tries > 5) {
420 		rv = EPROTO;
421 		goto out;
422 	}
423 
424 	rv = proto_cc_dupfid(pu, p9n->fid_base, nfid);
425 	if (rv)
426 		goto out;
427 
428 	p9pbuf_put_1(pb, P9PROTO_T_CREATE);
429 	p9pbuf_put_2(pb, tag);
430 	p9pbuf_put_4(pb, nfid);
431 	p9pbuf_put_str(pb, name);
432 	p9pbuf_put_4(pb, dirbit | (vap->va_mode & 0777));
433 	p9pbuf_put_1(pb, 0);
434 	if (p9p->protover == P9PROTO_VERSION_U)
435 		p9pbuf_put_str(pb, ""); /* extension[s] */
436 	GETRESPONSE(pb);
437 
438 	rv = proto_expect_qid(pu, pb, P9PROTO_R_CREATE, &nqid);
439 	if (rv)
440 		goto out;
441 
442 	/*
443 	 * Now, little problem here: create returns an *open* fid.
444 	 * So, clunk it and walk the parent directory to get a fid
445 	 * which is not open for I/O yet.
446 	 */
447 	proto_cc_clunkfid(pu, nfid, 0);
448 	nfid = NEXTFID(p9p);
449 
450 	p9pbuf_recycleout(pb);
451 	p9pbuf_put_1(pb, P9PROTO_T_WALK);
452 	p9pbuf_put_2(pb, tag);
453 	p9pbuf_put_4(pb, p9n->fid_base);
454 	p9pbuf_put_4(pb, nfid);
455 	p9pbuf_put_2(pb, 1);
456 	p9pbuf_put_str(pb, name);
457 	GETRESPONSE(pb);
458 
459 	/*
460 	 * someone removed it already? try again
461 	 * note: this is kind of lose/lose
462 	 */
463 	if (p9pbuf_get_type(pb) != P9PROTO_R_WALK)
464 		goto again;
465 
466 	pn_new = newp9pnode_va(pu, vap, nfid);
467 	qid2vattr(&pn_new->pn_va, &nqid);
468 	puffs_newinfo_setcookie(pni, pn_new);
469 
470  out:
471 	RETURN(rv);
472 }
473 
474 int
475 puffs9p_node_create(struct puffs_usermount *pu, void *opc, struct puffs_newinfo *pni,
476 	const struct puffs_cn *pcn, const struct vattr *va)
477 {
478 
479 	return nodecreate(pu, opc, pni, pcn->pcn_name, va, 0);
480 }
481 
482 int
483 puffs9p_node_mkdir(struct puffs_usermount *pu, void *opc, struct puffs_newinfo *pni,
484 	const struct puffs_cn *pcn, const struct vattr *va)
485 {
486 
487 	return nodecreate(pu, opc, pni, pcn->pcn_name,
488 	    va, P9PROTO_CPERM_DIR);
489 }
490 
491 /*
492  * Need to be a bit clever again: the fid is clunked no matter if
493  * the remove succeeds or not.  Re-getting a fid would be way too
494  * difficult in case the remove failed for a valid reason (directory
495  * not empty etcetc.).  So walk ourselves another fid to prod the
496  * ice with.
497  */
498 static int
499 noderemove(struct puffs_usermount *pu, struct puffs_node *pn)
500 {
501 	AUTOVAR(pu);
502 	struct p9pnode *p9n = pn->pn_data;
503 	p9pfid_t testfid = NEXTFID(p9p);
504 
505 	rv = proto_cc_dupfid(pu, p9n->fid_base, testfid);
506 	if (rv)
507 		goto out;
508 
509 	p9pbuf_put_1(pb, P9PROTO_T_REMOVE);
510 	p9pbuf_put_2(pb, tag);
511 	p9pbuf_put_4(pb, testfid);
512 
513 	/*
514 	 * XXX: error handling isn't very robust, but doom is impending
515 	 * anyway, so just accept we're going belly up and play dead
516 	 */
517 	GETRESPONSE(pb);
518 
519 	if (p9pbuf_get_type(pb) != P9PROTO_R_REMOVE) {
520 		rv = proto_handle_rerror(pu, pb);
521 	} else {
522 		proto_cc_clunkfid(pu, p9n->fid_base, 0);
523 		p9n->fid_base = P9P_INVALFID;
524 		puffs_pn_remove(pn);
525 	}
526 
527  out:
528 	if (rv == 0)
529 		puffs_setback(pcc, PUFFS_SETBACK_NOREF_N2);
530 
531 	RETURN(rv);
532 }
533 
534 int
535 puffs9p_node_remove(struct puffs_usermount *pu, void *opc, void *targ,
536 	const struct puffs_cn *pcn)
537 {
538 	struct puffs_node *pn = targ;
539 
540 	if (pn->pn_va.va_type == VDIR)
541 		return EISDIR;
542 
543 	return noderemove(pu, pn);
544 }
545 
546 int
547 puffs9p_node_rmdir(struct puffs_usermount *pu, void *opc, void *targ,
548 	const struct puffs_cn *pcn)
549 {
550 	struct puffs_node *pn = targ;
551 
552 	if (pn->pn_va.va_type != VDIR)
553 		return ENOTDIR;
554 
555 	return noderemove(pu, pn);
556 }
557 
558 /*
559  * 9P supports renames only for files within a directory
560  * from what I could tell.  So just support in-directory renames
561  * for now.
562  */
563 int
564 puffs9p_node_rename(struct puffs_usermount *pu, void *opc, void *src,
565 	const struct puffs_cn *pcn_src, void *targ_dir, void *targ,
566 	const struct puffs_cn *pcn_targ)
567 {
568 	AUTOVAR(pu);
569 	struct puffs_node *pn_src = src;
570 	struct p9pnode *p9n_src = pn_src->pn_data;
571 
572 	if (opc != targ_dir) {
573 		rv = EOPNOTSUPP;
574 		goto out;
575 	}
576 
577 	/* 9P doesn't allow to overwrite in rename */
578 	if (targ) {
579 		struct puffs_node *pn_targ = targ;
580 
581 		rv = noderemove(pu, pn_targ->pn_data);
582 		if (rv)
583 			goto out;
584 	}
585 
586 	p9pbuf_put_1(pb, P9PROTO_T_WSTAT);
587 	p9pbuf_put_2(pb, tag);
588 	p9pbuf_put_4(pb, p9n_src->fid_base);
589 	proto_make_stat(pu, pb, NULL, pcn_targ->pcn_name, pn_src->pn_va.va_type);
590 	GETRESPONSE(pb);
591 
592 	if (p9pbuf_get_type(pb) != P9PROTO_R_WSTAT)
593 		rv = proto_handle_rerror(pu, pb);
594 
595  out:
596 	RETURN(rv);
597 }
598 
599 /*
600  * - "here's one"
601  * - "9P"
602  * ~ "i'm not dead"
603  * - "you're not fooling anyone you know, you'll be stone dead in a minute
604  * - "he says he's not quite dead"
605  * - "isn't there anything you could do?"
606  * - *clunk*!
607  * - "thanks"
608  */
609 int
610 puffs9p_node_reclaim(struct puffs_usermount *pu, void *opc)
611 {
612 	struct puffs_node *pn = opc;
613 	struct p9pnode *p9n = pn->pn_data;
614 
615 	assert(LIST_EMPTY(&p9n->dir_openlist));
616 	assert(p9n->fid_read == P9P_INVALFID && p9n->fid_write == P9P_INVALFID);
617 
618 	proto_cc_clunkfid(pu, p9n->fid_base, 0);
619 	free(p9n);
620 	puffs_pn_put(pn);
621 
622 	return 0;
623 }
624