xref: /netbsd-src/usr.sbin/puffs/mount_psshfs/subr.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*      $NetBSD: subr.c,v 1.45 2007/12/13 14:59:00 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 1.45 2007/12/13 14:59:00 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 
68 static void
69 setpnva(struct puffs_usermount *pu, struct puffs_node *pn,
70 	const struct vattr *vap)
71 {
72 	struct psshfs_node *psn = pn->pn_data;
73 
74 	/*
75 	 * Check if the file was modified from below us.
76 	 * If so, invalidate page cache.  This is the only
77 	 * sensible place we can do this in.
78 	 */
79 	if (pn->pn_va.va_mtime.tv_sec != PUFFS_VNOVAL)
80 		if (pn->pn_va.va_mtime.tv_sec != vap->va_mtime.tv_sec
81 		    && pn->pn_va.va_type == VREG)
82 			puffs_inval_pagecache_node(pu, pn);
83 
84 	puffs_setvattr(&pn->pn_va, vap);
85 	psn->attrread = time(NULL);
86 }
87 
88 struct psshfs_dir *
89 lookup(struct psshfs_dir *bdir, size_t ndir, const char *name)
90 {
91 	struct psshfs_dir *test;
92 	int i;
93 
94 	for (i = 0; i < ndir; i++) {
95 		test = &bdir[i];
96 		if (test->valid != 1)
97 			continue;
98 		if (strcmp(test->entryname, name) == 0)
99 			return test;
100 	}
101 
102 	return NULL;
103 }
104 
105 static struct psshfs_dir *
106 lookup_by_entry(struct psshfs_dir *bdir, size_t ndir, struct puffs_node *entry)
107 {
108 	struct psshfs_dir *test;
109 	int i;
110 
111 	for (i = 0; i < ndir; i++) {
112 		test = &bdir[i];
113 		if (test->valid != 1)
114 			continue;
115 		if (test->entry == entry)
116 			return test;
117 	}
118 
119 	return NULL;
120 }
121 
122 
123 void
124 closehandles(struct puffs_usermount *pu, struct psshfs_node *psn, int which)
125 {
126 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
127 	struct puffs_framebuf *pb1, *pb2;
128 	uint32_t reqid;
129 
130 	if (psn->fhand_r && (which & HANDLE_READ)) {
131 		assert(psn->lazyopen_r == NULL);
132 
133 		pb1 = psbuf_makeout();
134 		reqid = NEXTREQ(pctx);
135 		psbuf_req_data(pb1, SSH_FXP_CLOSE, reqid,
136 		    psn->fhand_r, psn->fhand_r_len);
137 		puffs_framev_enqueue_justsend(pu, pctx->sshfd, pb1, 1, 0);
138 		free(psn->fhand_r);
139 		psn->fhand_r = NULL;
140 	}
141 
142 	if (psn->fhand_w && (which & HANDLE_WRITE)) {
143 		assert(psn->lazyopen_w == NULL);
144 
145 		pb2 = psbuf_makeout();
146 		reqid = NEXTREQ(pctx);
147 		psbuf_req_data(pb2, SSH_FXP_CLOSE, reqid,
148 		    psn->fhand_w, psn->fhand_w_len);
149 		puffs_framev_enqueue_justsend(pu, pctx->sshfd, pb2, 1, 0);
150 		free(psn->fhand_w);
151 		psn->fhand_w = NULL;
152 	}
153 
154 	psn->stat |= PSN_HANDLECLOSE;
155 }
156 
157 void
158 lazyopen_rresp(struct puffs_usermount *pu, struct puffs_framebuf *pb,
159 	void *arg, int error)
160 {
161 	struct psshfs_node *psn = arg;
162 
163 	/* XXX: this is not enough */
164 	if (psn->stat & PSN_RECLAIMED) {
165 		error = ENOENT;
166 		goto moreout;
167 	}
168 	if (error)
169 		goto out;
170 
171 	error = psbuf_expect_handle(pb, &psn->fhand_r, &psn->fhand_r_len);
172 
173  out:
174 	psn->lazyopen_err_r = error;
175 	psn->lazyopen_r = NULL;
176 	if (error)
177 		psn->stat &= ~PSN_DOLAZY_R;
178 	if (psn->stat & PSN_HANDLECLOSE && (psn->stat & PSN_LAZYWAIT_R) == 0)
179 		closehandles(pu, psn, HANDLE_READ);
180  moreout:
181 	puffs_framebuf_destroy(pb);
182 }
183 
184 void
185 lazyopen_wresp(struct puffs_usermount *pu, struct puffs_framebuf *pb,
186 	void *arg, int error)
187 {
188 	struct psshfs_node *psn = arg;
189 
190 	/* XXX: this is not enough */
191 	if (psn->stat & PSN_RECLAIMED) {
192 		error = ENOENT;
193 		goto moreout;
194 	}
195 	if (error)
196 		goto out;
197 
198 	error = psbuf_expect_handle(pb, &psn->fhand_w, &psn->fhand_w_len);
199 
200  out:
201 	psn->lazyopen_err_w = error;
202 	psn->lazyopen_w = NULL;
203 	if (error)
204 		psn->stat &= ~PSN_DOLAZY_W;
205 	if (psn->stat & PSN_HANDLECLOSE && (psn->stat & PSN_LAZYWAIT_W) == 0)
206 		closehandles(pu, psn, HANDLE_WRITE);
207  moreout:
208 	puffs_framebuf_destroy(pb);
209 }
210 
211 struct readdirattr {
212 	struct psshfs_node *psn;
213 	int idx;
214 	char entryname[MAXPATHLEN+1];
215 };
216 
217 int
218 getpathattr(struct puffs_usermount *pu, const char *path, struct vattr *vap)
219 {
220 	PSSHFSAUTOVAR(pu);
221 
222 	psbuf_req_str(pb, SSH_FXP_LSTAT, reqid, path);
223 	GETRESPONSE(pb);
224 
225 	rv = psbuf_expect_attrs(pb, vap);
226 
227  out:
228 	PSSHFSRETURN(rv);
229 }
230 
231 int
232 getnodeattr(struct puffs_usermount *pu, struct puffs_node *pn)
233 {
234 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
235 	struct psshfs_node *psn = pn->pn_data;
236 	struct vattr va;
237 	int rv;
238 
239 	if (!psn->attrread || REFRESHTIMEOUT(pctx, time(NULL)-psn->attrread)) {
240 		rv = getpathattr(pu, PNPATH(pn), &va);
241 		if (rv)
242 			return rv;
243 
244 		setpnva(pu, pn, &va);
245 	}
246 
247 	return 0;
248 }
249 
250 int
251 sftp_readdir(struct puffs_usermount *pu, struct psshfs_ctx *pctx,
252 	struct puffs_node *pn)
253 {
254 	struct puffs_cc *pcc = puffs_cc_getcc(pu);
255 	struct psshfs_node *psn = pn->pn_data;
256 	struct psshfs_dir *olddir, *testd;
257 	struct puffs_framebuf *pb;
258 	uint32_t reqid = NEXTREQ(pctx);
259 	uint32_t count, dhandlen;
260 	char *dhand = NULL;
261 	size_t nent;
262 	char *longname = NULL;
263 	int idx, rv;
264 
265 	assert(pn->pn_va.va_type == VDIR);
266 	idx = 0;
267 	olddir = psn->dir;
268 	nent = psn->dentnext;
269 
270 	if (psn->dir && psn->dentread
271 	    && !REFRESHTIMEOUT(pctx, time(NULL) - psn->dentread))
272 		return 0;
273 
274 	if (psn->dentread) {
275 		if ((rv = puffs_inval_namecache_dir(pu, pn)))
276 			warn("readdir: dcache inval fail %p", pn);
277 	}
278 
279 	pb = psbuf_makeout();
280 	psbuf_req_str(pb, SSH_FXP_OPENDIR, reqid, PNPATH(pn));
281 	if (puffs_framev_enqueue_cc(pcc, pctx->sshfd, pb, 0) == -1) {
282 		rv = errno;
283 		goto wayout;
284 	}
285 	rv = psbuf_expect_handle(pb, &dhand, &dhandlen);
286 	if (rv)
287 		goto wayout;
288 
289 	/*
290 	 * Well, the following is O(n^2), so feel free to improve if it
291 	 * gets too taxing on your system.
292 	 */
293 
294 	/*
295 	 * note: for the "getattr in batch" to work, this must be before
296 	 * the attribute-getting.  Otherwise times for first entries in
297 	 * large directories might expire before the directory itself and
298 	 * result in one-by-one attribute fetching.
299 	 */
300 	psn->dentread = time(NULL);
301 
302 	psn->dentnext = 0;
303 	psn->denttot = 0;
304 	psn->dir = NULL;
305 
306 	for (;;) {
307 		reqid = NEXTREQ(pctx);
308 		psbuf_recycleout(pb);
309 		psbuf_req_data(pb, SSH_FXP_READDIR, reqid, dhand, dhandlen);
310 		GETRESPONSE(pb);
311 
312 		/* check for EOF */
313 		if (psbuf_get_type(pb) == SSH_FXP_STATUS) {
314 			rv = psbuf_expect_status(pb);
315 			goto out;
316 		}
317 		rv = psbuf_expect_name(pb, &count);
318 		if (rv)
319 			goto out;
320 
321 		for (; count--; idx++) {
322 			if (idx == psn->denttot)
323 				allocdirs(psn);
324 			if ((rv = psbuf_get_str(pb,
325 			    &psn->dir[idx].entryname, NULL)))
326 				goto out;
327 			if ((rv = psbuf_get_str(pb, &longname, NULL)) != 0)
328 				goto out;
329 			if ((rv = psbuf_get_vattr(pb, &psn->dir[idx].va)) != 0)
330 				goto out;
331 			if (sscanf(longname, "%*s%d",
332 			    &psn->dir[idx].va.va_nlink) != 1) {
333 				rv = EPROTO;
334 				goto out;
335 			}
336 			free(longname);
337 			longname = NULL;
338 
339 			/*
340 			 * Check if we already have a psshfs_dir for the
341 			 * name we are processing.  If so, use the old one.
342 			 * If not, create a new one
343 			 */
344 			testd = lookup(olddir, nent, psn->dir[idx].entryname);
345 			if (testd) {
346 				psn->dir[idx].entry = testd->entry;
347 				/*
348 				 * Has entry.  Update attributes to what
349 				 * we just got from the server.
350 				 */
351 				if (testd->entry) {
352 					setpnva(pu, testd->entry,
353 					    &psn->dir[idx].va);
354 					psn->dir[idx].va.va_fileid
355 					    = testd->entry->pn_va.va_fileid;
356 
357 				/*
358 				 * No entry.  This can happen in two cases:
359 				 * 1) the file was created "behind our back"
360 				 *    on the server
361 				 * 2) we do two readdirs before we instantiate
362 				 *    the node (or run with -t 0).
363 				 *
364 				 * Cache attributes from the server in
365 				 * case we want to instantiate this node
366 				 * soon.  Also preserve the old inode number
367 				 * which was given when the dirent was created.
368 				 */
369 				} else {
370 					psn->dir[idx].va.va_fileid
371 					    = testd->va.va_fileid;
372 					testd->va = psn->dir[idx].va;
373 				}
374 
375 			/* No previous entry?  Initialize this one. */
376 			} else {
377 				psn->dir[idx].entry = NULL;
378 				psn->dir[idx].va.va_fileid = pctx->nextino++;
379 			}
380 			psn->dir[idx].attrread = psn->dentread;
381 			psn->dir[idx].valid = 1;
382 		}
383 	}
384 
385  out:
386 	/* XXX: rv */
387 	psn->dentnext = idx;
388 	freedircache(olddir, nent);
389 
390 	reqid = NEXTREQ(pctx);
391 	psbuf_recycleout(pb);
392 	psbuf_req_data(pb, SSH_FXP_CLOSE, reqid, dhand, dhandlen);
393 	puffs_framev_enqueue_justsend(pu, pctx->sshfd, pb, 1, 0);
394 	free(dhand);
395 	free(longname);
396 
397 	return rv;
398 
399  wayout:
400 	free(dhand);
401 	PSSHFSRETURN(rv);
402 }
403 
404 struct puffs_node *
405 makenode(struct puffs_usermount *pu, struct puffs_node *parent,
406 	struct psshfs_dir *pd, const struct vattr *vap)
407 {
408 	struct psshfs_node *psn_parent = parent->pn_data;
409 	struct psshfs_node *psn;
410 	struct puffs_node *pn;
411 
412 	psn = emalloc(sizeof(struct psshfs_node));
413 	memset(psn, 0, sizeof(struct psshfs_node));
414 
415 	pn = puffs_pn_new(pu, psn);
416 	if (!pn) {
417 		free(psn);
418 		return NULL;
419 	}
420 	setpnva(pu, pn, &pd->va);
421 	setpnva(pu, pn, vap);
422 	psn->attrread = pd->attrread;
423 
424 	pd->entry = pn;
425 	psn->parent = parent;
426 	psn_parent->childcount++;
427 
428 	TAILQ_INIT(&psn->pw);
429 
430 	return pn;
431 }
432 
433 struct puffs_node *
434 allocnode(struct puffs_usermount *pu, struct puffs_node *parent,
435 	const char *entryname, const struct vattr *vap)
436 {
437 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
438 	struct psshfs_dir *pd;
439 	struct puffs_node *pn;
440 
441 	pd = direnter(parent, entryname);
442 
443 	pd->va.va_fileid = pctx->nextino++;
444 	if (vap->va_type == VDIR) {
445 		pd->va.va_nlink = 2;
446 		parent->pn_va.va_nlink++;
447 	} else {
448 		pd->va.va_nlink = 1;
449 	}
450 
451 	pn = makenode(pu, parent, pd, vap);
452 	if (pn)
453 		pd->va.va_fileid = pn->pn_va.va_fileid;
454 
455 	return pn;
456 }
457 
458 struct psshfs_dir *
459 direnter(struct puffs_node *parent, const char *entryname)
460 {
461 	struct psshfs_node *psn_parent = parent->pn_data;
462 	struct psshfs_dir *pd;
463 	int i;
464 
465 	/* create directory entry */
466 	if (psn_parent->denttot == psn_parent->dentnext)
467 		allocdirs(psn_parent);
468 
469 	i = psn_parent->dentnext;
470 	pd = &psn_parent->dir[i];
471 	pd->entryname = estrdup(entryname);
472 	pd->valid = 1;
473 	pd->attrread = 0;
474 	puffs_vattr_null(&pd->va);
475 	psn_parent->dentnext++;
476 
477 	return pd;
478 }
479 
480 void
481 doreclaim(struct puffs_node *pn)
482 {
483 	struct psshfs_node *psn = pn->pn_data;
484 	struct psshfs_node *psn_parent;
485 	struct psshfs_dir *dent;
486 
487 	psn_parent = psn->parent->pn_data;
488 	psn_parent->childcount--;
489 
490 	/*
491 	 * Null out entry from directory.  Do not treat a missing entry
492 	 * as an invariant error, since the node might be removed from
493 	 * under us, and we might do a readdir before the reclaim resulting
494 	 * in no directory entry in the parent directory.
495 	 */
496 	dent = lookup_by_entry(psn_parent->dir, psn_parent->dentnext, pn);
497 	if (dent)
498 		dent->entry = NULL;
499 
500 	if (pn->pn_va.va_type == VDIR) {
501 		freedircache(psn->dir, psn->dentnext);
502 		psn->denttot = psn->dentnext = 0;
503 	}
504 	if (psn->symlink)
505 		free(psn->symlink);
506 
507 	puffs_pn_put(pn);
508 }
509 
510 void
511 nukenode(struct puffs_node *node, const char *entryname, int reclaim)
512 {
513 	struct psshfs_node *psn, *psn_parent;
514 	struct psshfs_dir *pd;
515 
516 	psn = node->pn_data;
517 	psn_parent = psn->parent->pn_data;
518 	pd = lookup(psn_parent->dir, psn_parent->dentnext, entryname);
519 	assert(pd != NULL);
520 	pd->valid = 0;
521 	free(pd->entryname);
522 	pd->entryname = NULL;
523 
524 	if (node->pn_va.va_type == VDIR)
525 		psn->parent->pn_va.va_nlink--;
526 
527 	if (reclaim)
528 		doreclaim(node);
529 }
530