xref: /netbsd/usr.sbin/puffs/mount_psshfs/subr.c (revision 21913eab)
1 /*      $NetBSD: subr.c,v 1.38 2007/11/30 19:02:41 pooka Exp $        */
2 
3 /*
4  * Copyright (c) 2006  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: subr.c,v 1.38 2007/11/30 19:02:41 pooka Exp $");
31 #endif /* !lint */
32 
33 #include <assert.h>
34 #include <err.h>
35 #include <errno.h>
36 #include <puffs.h>
37 #include <stdlib.h>
38 #include <util.h>
39 
40 #include "psshfs.h"
41 #include "sftp_proto.h"
42 
43 static void
44 freedircache(struct psshfs_dir *base, size_t count)
45 {
46 	int i;
47 
48 	for (i = 0; i < count; i++) {
49 		free(base[i].entryname);
50 		base[i].entryname = NULL;
51 	}
52 
53 	free(base);
54 }
55 
56 #define ENTRYCHUNK 16
57 static void
58 allocdirs(struct psshfs_node *psn)
59 {
60 	size_t oldtot = psn->denttot;
61 
62 	psn->denttot += ENTRYCHUNK;
63 	psn->dir = erealloc(psn->dir,
64 	    psn->denttot * sizeof(struct psshfs_dir));
65 	memset(psn->dir + oldtot, 0, ENTRYCHUNK * sizeof(struct psshfs_dir));
66 
67 	psn->da = erealloc(psn->da, psn->denttot * sizeof(struct delayattr));
68 }
69 
70 static void
71 setpnva(struct puffs_usermount *pu, struct puffs_node *pn,
72 	const struct vattr *vap)
73 {
74 	struct psshfs_node *psn = pn->pn_data;
75 
76 	/*
77 	 * Check if the file was modified from below us.
78 	 * If so, invalidate page cache.  This is the only
79 	 * sensible place we can do this in.
80 	 */
81 	if (pn->pn_va.va_mtime.tv_sec != PUFFS_VNOVAL)
82 		if (pn->pn_va.va_mtime.tv_sec != vap->va_mtime.tv_sec
83 		    && pn->pn_va.va_type == VREG)
84 			puffs_inval_pagecache_node(pu, pn);
85 
86 	puffs_setvattr(&pn->pn_va, vap);
87 	psn->attrread = time(NULL);
88 }
89 
90 struct psshfs_dir *
91 lookup(struct psshfs_dir *bdir, size_t ndir, const char *name)
92 {
93 	struct psshfs_dir *test;
94 	int i;
95 
96 	for (i = 0; i < ndir; i++) {
97 		test = &bdir[i];
98 		if (test->valid != 1)
99 			continue;
100 		if (strcmp(test->entryname, name) == 0)
101 			return test;
102 	}
103 
104 	return NULL;
105 }
106 
107 static struct psshfs_dir *
108 lookup_by_entry(struct psshfs_dir *bdir, size_t ndir, struct puffs_node *entry)
109 {
110 	struct psshfs_dir *test;
111 	int i;
112 
113 	for (i = 0; i < ndir; i++) {
114 		test = &bdir[i];
115 		if (test->valid != 1)
116 			continue;
117 		if (test->entry == entry)
118 			return test;
119 	}
120 
121 	return NULL;
122 }
123 
124 
125 void
126 closehandles(struct puffs_usermount *pu, struct psshfs_node *psn, int which)
127 {
128 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
129 	struct puffs_framebuf *pb1, *pb2;
130 	uint32_t reqid;
131 
132 	if (psn->fhand_r && (which & HANDLE_READ)) {
133 		assert(psn->lazyopen_r == NULL);
134 
135 		pb1 = psbuf_makeout();
136 		reqid = NEXTREQ(pctx);
137 		psbuf_req_data(pb1, SSH_FXP_CLOSE, reqid,
138 		    psn->fhand_r, psn->fhand_r_len);
139 		puffs_framev_enqueue_justsend(pu, pctx->sshfd, pb1, 1, 0);
140 		free(psn->fhand_r);
141 		psn->fhand_r = NULL;
142 	}
143 
144 	if (psn->fhand_w && (which & HANDLE_WRITE)) {
145 		assert(psn->lazyopen_w == NULL);
146 
147 		pb2 = psbuf_makeout();
148 		reqid = NEXTREQ(pctx);
149 		psbuf_req_data(pb2, SSH_FXP_CLOSE, reqid,
150 		    psn->fhand_w, psn->fhand_w_len);
151 		puffs_framev_enqueue_justsend(pu, pctx->sshfd, pb2, 1, 0);
152 		free(psn->fhand_w);
153 		psn->fhand_w = NULL;
154 	}
155 
156 	psn->stat |= PSN_HANDLECLOSE;
157 }
158 
159 void
160 lazyopen_rresp(struct puffs_usermount *pu, struct puffs_framebuf *pb,
161 	void *arg, int error)
162 {
163 	struct psshfs_node *psn = arg;
164 
165 	/* XXX: this is not enough */
166 	if (psn->stat & PSN_RECLAIMED) {
167 		error = ENOENT;
168 		goto moreout;
169 	}
170 	if (error)
171 		goto out;
172 
173 	error = psbuf_expect_handle(pb, &psn->fhand_r, &psn->fhand_r_len);
174 
175  out:
176 	psn->lazyopen_err_r = error;
177 	psn->lazyopen_r = NULL;
178 	if (error)
179 		psn->stat &= ~PSN_DOLAZY_R;
180 	if (psn->stat & PSN_HANDLECLOSE && (psn->stat & PSN_LAZYWAIT_R) == 0)
181 		closehandles(pu, psn, HANDLE_READ);
182  moreout:
183 	puffs_framebuf_destroy(pb);
184 }
185 
186 void
187 lazyopen_wresp(struct puffs_usermount *pu, struct puffs_framebuf *pb,
188 	void *arg, int error)
189 {
190 	struct psshfs_node *psn = arg;
191 
192 	/* XXX: this is not enough */
193 	if (psn->stat & PSN_RECLAIMED) {
194 		error = ENOENT;
195 		goto moreout;
196 	}
197 	if (error)
198 		goto out;
199 
200 	error = psbuf_expect_handle(pb, &psn->fhand_w, &psn->fhand_w_len);
201 
202  out:
203 	psn->lazyopen_err_w = error;
204 	psn->lazyopen_w = NULL;
205 	if (error)
206 		psn->stat &= ~PSN_DOLAZY_W;
207 	if (psn->stat & PSN_HANDLECLOSE && (psn->stat & PSN_LAZYWAIT_W) == 0)
208 		closehandles(pu, psn, HANDLE_WRITE);
209  moreout:
210 	puffs_framebuf_destroy(pb);
211 }
212 
213 struct readdirattr {
214 	struct psshfs_node *psn;
215 	int idx;
216 	char entryname[MAXPATHLEN+1];
217 };
218 
219 static void
220 readdir_getattr_resp(struct puffs_usermount *pu,
221 	struct puffs_framebuf *pb, void *arg, int error)
222 {
223 	struct readdirattr *rda = arg;
224 	struct psshfs_node *psn = rda->psn;
225 	struct psshfs_node *psn_targ = NULL;
226 	struct psshfs_dir *pdir = NULL;
227 	struct vattr va;
228 
229 	/* XXX: this is not enough */
230 	if (psn->stat & PSN_RECLAIMED)
231 		goto out;
232 
233 	if (error)
234 		goto out;
235 
236 	pdir = lookup(psn->dir, psn->denttot, rda->entryname);
237 	if (!pdir)
238 		goto out;
239 
240 	if (psbuf_expect_attrs(pb, &va))
241 		goto out;
242 
243 	if (pdir->entry) {
244 		psn_targ = pdir->entry->pn_data;
245 
246 		setpnva(pu, pdir->entry, &va);
247 	} else {
248 		puffs_setvattr(&pdir->va, &va);
249 		pdir->attrread = time(NULL);
250 	}
251 
252  out:
253 	if (psn_targ) {
254 		psn_targ->getattr_pb = NULL;
255 		assert(pdir->getattr_pb == NULL);
256 	} else if (pdir) {
257 		pdir->getattr_pb = NULL;
258 	}
259 
260 	free(rda);
261 	puffs_framebuf_destroy(pb);
262 }
263 
264 static void
265 readdir_getattr(struct puffs_usermount *pu, struct psshfs_node *psn,
266 	const char *basepath, int idx)
267 {
268 	char path[MAXPATHLEN+1];
269 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
270 	struct psshfs_dir *pdir = psn->dir;
271 	struct puffs_framebuf *pb;
272 	struct readdirattr *rda;
273 	const char *entryname = pdir[idx].entryname;
274 	uint32_t reqid = NEXTREQ(pctx);
275 
276 	rda = emalloc(sizeof(struct readdirattr));
277 	rda->psn = psn;
278 	rda->idx = idx;
279 	strlcpy(rda->entryname, entryname, sizeof(rda->entryname));
280 
281 	strcpy(path, basepath);
282 	strcat(path, "/");
283 	strlcat(path, entryname, sizeof(path));
284 
285 	pb = psbuf_makeout();
286 	psbuf_req_str(pb, SSH_FXP_LSTAT, reqid, path);
287 	psn->da[psn->nextda].pufbuf = pb;
288 	psn->da[psn->nextda].rda = rda;
289 	psn->nextda++;
290 }
291 
292 static void
293 readdir_getattr_send(struct puffs_usermount *pu, struct psshfs_node *psn)
294 {
295 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
296 	struct psshfs_dir *pdir = psn->dir;
297 	struct psshfs_node *psn_targ;
298 	struct readdirattr *rda;
299 	size_t i;
300 	int rv = 0;
301 
302 	for (i = 0; i < psn->nextda; i++) {
303 		rda = psn->da[i].rda;
304 		if (pdir[rda->idx].entry) {
305 			psn_targ = pdir[rda->idx].entry->pn_data;
306 			psn_targ->getattr_pb = psn->da[i].pufbuf;
307 		} else {
308 			pdir[rda->idx].getattr_pb = psn->da[i].pufbuf;
309 		}
310 		SENDCB(psn->da[i].pufbuf, readdir_getattr_resp, rda);
311 	}
312 
313  out:
314 	return;
315 }
316 
317 int
318 getpathattr(struct puffs_usermount *pu, const char *path, struct vattr *vap)
319 {
320 	PSSHFSAUTOVAR(pu);
321 
322 	psbuf_req_str(pb, SSH_FXP_LSTAT, reqid, path);
323 	GETRESPONSE(pb);
324 
325 	rv = psbuf_expect_attrs(pb, vap);
326 
327  out:
328 	PSSHFSRETURN(rv);
329 }
330 
331 int
332 getnodeattr(struct puffs_usermount *pu, struct puffs_node *pn)
333 {
334 	struct puffs_cc *pcc = puffs_cc_getcc(pu);
335 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
336 	struct psshfs_node *psn = pn->pn_data;
337 	struct vattr va;
338 	int rv, dohardway;
339 
340 	if (!psn->attrread || REFRESHTIMEOUT(pctx, time(NULL)-psn->attrread)) {
341 		dohardway = 1;
342 		if (psn->getattr_pb) {
343 			rv=puffs_framev_framebuf_ccpromote(psn->getattr_pb,pcc);
344 			if (rv == 0) {
345 				rv = psbuf_expect_attrs(psn->getattr_pb, &va);
346 				puffs_framebuf_destroy(psn->getattr_pb);
347 				psn->getattr_pb = NULL;
348 				if (rv == 0)
349 					dohardway = 0;
350 			}
351 		}
352 
353 		if (dohardway) {
354 			rv = getpathattr(pu, PNPATH(pn), &va);
355 			if (rv)
356 				return rv;
357 		}
358 
359 		setpnva(pu, pn, &va);
360 	}
361 
362 	return 0;
363 }
364 
365 int
366 sftp_readdir(struct puffs_cc *pcc, struct psshfs_ctx *pctx,
367 	struct puffs_node *pn)
368 {
369 	struct puffs_usermount *pu = puffs_cc_getusermount(pcc);
370 	struct psshfs_node *psn = pn->pn_data;
371 	struct psshfs_dir *olddir, *testd;
372 	struct puffs_framebuf *pb;
373 	uint32_t reqid = NEXTREQ(pctx);
374 	uint32_t count, dhandlen;
375 	char *dhand = NULL;
376 	size_t nent;
377 	char *longname = NULL;
378 	int idx, rv;
379 
380 	assert(pn->pn_va.va_type == VDIR);
381 	idx = 0;
382 	olddir = psn->dir;
383 	nent = psn->dentnext;
384 
385 	if (psn->dir && psn->dentread
386 	    && !REFRESHTIMEOUT(pctx, time(NULL) - psn->dentread))
387 		return 0;
388 
389 	if ((rv = puffs_inval_namecache_dir(pu, pn)))
390 		warn("readdir: dcache inval fail %p", pn);
391 
392 	pb = psbuf_makeout();
393 	psbuf_req_str(pb, SSH_FXP_OPENDIR, reqid, PNPATH(pn));
394 	if (puffs_framev_enqueue_cc(pcc, pctx->sshfd, pb, 0) == -1) {
395 		rv = errno;
396 		goto wayout;
397 	}
398 	rv = psbuf_expect_handle(pb, &dhand, &dhandlen);
399 	if (rv)
400 		goto wayout;
401 
402 	/*
403 	 * Well, the following is O(n^2), so feel free to improve if it
404 	 * gets too taxing on your system.
405 	 */
406 
407 	/*
408 	 * note: for the "getattr in batch" to work, this must be before
409 	 * the attribute-getting.  Otherwise times for first entries in
410 	 * large directories might expire before the directory itself and
411 	 * result in one-by-one attribute fetching.
412 	 */
413 	psn->dentread = time(NULL);
414 
415 	psn->dentnext = 0;
416 	psn->denttot = 0;
417 	psn->dir = NULL;
418 	psn->nextda = 0;
419 
420 	for (;;) {
421 		reqid = NEXTREQ(pctx);
422 		psbuf_recycleout(pb);
423 		psbuf_req_data(pb, SSH_FXP_READDIR, reqid, dhand, dhandlen);
424 		GETRESPONSE(pb);
425 
426 		/* check for EOF */
427 		if (psbuf_get_type(pb) == SSH_FXP_STATUS) {
428 			rv = psbuf_expect_status(pb);
429 			goto out;
430 		}
431 		rv = psbuf_expect_name(pb, &count);
432 		if (rv)
433 			goto out;
434 
435 		for (; count--; idx++) {
436 			if (idx == psn->denttot)
437 				allocdirs(psn);
438 			if ((rv = psbuf_get_str(pb,
439 			    &psn->dir[idx].entryname, NULL)))
440 				goto out;
441 			if ((rv = psbuf_get_str(pb, &longname, NULL)) != 0)
442 				goto out;
443 			if ((rv = psbuf_get_vattr(pb, &psn->dir[idx].va)) != 0)
444 				goto out;
445 			if (sscanf(longname, "%*s%d",
446 			    &psn->dir[idx].va.va_nlink) != 1) {
447 				rv = EPROTO;
448 				goto out;
449 			}
450 			free(longname);
451 			longname = NULL;
452 
453 			testd = lookup(olddir, nent, psn->dir[idx].entryname);
454 			if (testd) {
455 				psn->dir[idx].entry = testd->entry;
456 				psn->dir[idx].va = testd->va;
457 			} else {
458 				psn->dir[idx].entry = NULL;
459 				psn->dir[idx].va.va_fileid = pctx->nextino++;
460 			}
461 			/*
462 			 * XXX: there's a dangling pointer race here if
463 			 * the server responds to our queries out-of-order.
464 			 * fixxxme some day
465 			 */
466 			readdir_getattr(puffs_cc_getusermount(pcc),
467 			    psn, PNPATH(pn), idx);
468 
469 			psn->dir[idx].valid = 1;
470 		}
471 	}
472 
473  out:
474 	/* fire off getattr requests */
475 	readdir_getattr_send(pu, psn);
476 
477 	/* XXX: rv */
478 	psn->dentnext = idx;
479 	freedircache(olddir, nent);
480 
481 	reqid = NEXTREQ(pctx);
482 	psbuf_recycleout(pb);
483 	psbuf_req_data(pb, SSH_FXP_CLOSE, reqid, dhand, dhandlen);
484 	puffs_framev_enqueue_justsend(pu, pctx->sshfd, pb, 1, 0);
485 	free(dhand);
486 	free(longname);
487 
488 	return rv;
489 
490  wayout:
491 	free(dhand);
492 	PSSHFSRETURN(rv);
493 }
494 
495 struct puffs_node *
496 makenode(struct puffs_usermount *pu, struct puffs_node *parent,
497 	struct psshfs_dir *pd, const struct vattr *vap)
498 {
499 	struct psshfs_node *psn_parent = parent->pn_data;
500 	struct psshfs_node *psn;
501 	struct puffs_node *pn;
502 
503 	psn = emalloc(sizeof(struct psshfs_node));
504 	memset(psn, 0, sizeof(struct psshfs_node));
505 
506 	pn = puffs_pn_new(pu, psn);
507 	if (!pn) {
508 		free(psn);
509 		return NULL;
510 	}
511 	setpnva(pu, pn, &pd->va);
512 	setpnva(pu, pn, vap);
513 
514 	pd->entry = pn;
515 	psn->parent = parent;
516 	psn_parent->childcount++;
517 
518 	TAILQ_INIT(&psn->pw);
519 
520 	if (pd->getattr_pb) {
521 		psn->getattr_pb = pd->getattr_pb;
522 		pd->getattr_pb = NULL;
523 	}
524 
525 	return pn;
526 }
527 
528 struct puffs_node *
529 allocnode(struct puffs_usermount *pu, struct puffs_node *parent,
530 	const char *entryname, const struct vattr *vap)
531 {
532 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
533 	struct psshfs_dir *pd;
534 	struct puffs_node *pn;
535 
536 	pd = direnter(parent, entryname);
537 
538 	pd->va.va_fileid = pctx->nextino++;
539 	if (vap->va_type == VDIR) {
540 		pd->va.va_nlink = 2;
541 		parent->pn_va.va_nlink++;
542 	} else {
543 		pd->va.va_nlink = 1;
544 	}
545 
546 	pn = makenode(pu, parent, pd, vap);
547 	if (pn)
548 		pd->va.va_fileid = pn->pn_va.va_fileid;
549 
550 	return pn;
551 }
552 
553 struct psshfs_dir *
554 direnter(struct puffs_node *parent, const char *entryname)
555 {
556 	struct psshfs_node *psn_parent = parent->pn_data;
557 	struct psshfs_dir *pd;
558 	int i;
559 
560 	/* create directory entry */
561 	if (psn_parent->denttot == psn_parent->dentnext)
562 		allocdirs(psn_parent);
563 
564 	i = psn_parent->dentnext;
565 	pd = &psn_parent->dir[i];
566 	pd->entryname = estrdup(entryname);
567 	pd->valid = 1;
568 	pd->attrread = 0;
569 	puffs_vattr_null(&pd->va);
570 	psn_parent->dentnext++;
571 
572 	return pd;
573 }
574 
575 void
576 doreclaim(struct puffs_node *pn)
577 {
578 	struct psshfs_node *psn = pn->pn_data;
579 	struct psshfs_node *psn_parent;
580 	struct psshfs_dir *dent;
581 
582 	psn_parent = psn->parent->pn_data;
583 	psn_parent->childcount--;
584 
585 	/*
586 	 * Null out entry from directory.  Do not treat a missing entry
587 	 * as an invariant error, since the node might be removed from
588 	 * under us, and we might do a readdir before the reclaim resulting
589 	 * in no directory entry in the parent directory.
590 	 */
591 	dent = lookup_by_entry(psn_parent->dir, psn_parent->dentnext, pn);
592 	if (dent)
593 		dent->entry = NULL;
594 
595 	if (pn->pn_va.va_type == VDIR) {
596 		freedircache(psn->dir, psn->dentnext);
597 		psn->denttot = psn->dentnext = 0;
598 		free(psn->da);
599 	}
600 	if (psn->symlink)
601 		free(psn->symlink);
602 
603 	puffs_pn_put(pn);
604 }
605 
606 void
607 nukenode(struct puffs_node *node, const char *entryname, int reclaim)
608 {
609 	struct psshfs_node *psn, *psn_parent;
610 	struct psshfs_dir *pd;
611 
612 	psn = node->pn_data;
613 	psn_parent = psn->parent->pn_data;
614 	pd = lookup(psn_parent->dir, psn_parent->dentnext, entryname);
615 	assert(pd != NULL);
616 	pd->valid = 0;
617 	free(pd->entryname);
618 	pd->entryname = NULL;
619 
620 	if (node->pn_va.va_type == VDIR)
621 		psn->parent->pn_va.va_nlink--;
622 
623 	if (reclaim)
624 		doreclaim(node);
625 }
626