xref: /netbsd-src/usr.sbin/puffs/mount_psshfs/subr.c (revision 7fa608457b817eca6e0977b37f758ae064f3c99c)
1 /*      $NetBSD: subr.c,v 1.33 2007/11/10 18:36:06 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 1.33 2007/11/10 18:36:06 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 struct psshfs_dir *
71 lookup(struct psshfs_dir *bdir, size_t ndir, const char *name)
72 {
73 	struct psshfs_dir *test;
74 	int i;
75 
76 	for (i = 0; i < ndir; i++) {
77 		test = &bdir[i];
78 		if (test->valid != 1)
79 			continue;
80 		if (strcmp(test->entryname, name) == 0)
81 			return test;
82 	}
83 
84 	return NULL;
85 }
86 
87 static struct psshfs_dir *
88 lookup_by_entry(struct psshfs_dir *bdir, size_t ndir, struct puffs_node *entry)
89 {
90 	struct psshfs_dir *test;
91 	int i;
92 
93 	for (i = 0; i < ndir; i++) {
94 		test = &bdir[i];
95 		if (test->valid != 1)
96 			continue;
97 		if (test->entry == entry)
98 			return test;
99 	}
100 
101 	return NULL;
102 }
103 
104 struct readdirattr {
105 	struct psshfs_node *psn;
106 	int idx;
107 	char entryname[MAXPATHLEN+1];
108 };
109 
110 static void
111 readdir_getattr_resp(struct puffs_usermount *pu,
112 	struct puffs_framebuf *pb, void *arg, int error)
113 {
114 	struct readdirattr *rda = arg;
115 	struct psshfs_node *psn = rda->psn;
116 	struct psshfs_node *psn_targ = NULL;
117 	struct psshfs_dir *pdir = NULL;
118 	struct vattr va;
119 
120 	/* XXX: this is not enough */
121 	if (psn->stat & PSN_RECLAIMED)
122 		goto out;
123 
124 	if (error)
125 		goto out;
126 
127 	pdir = lookup(psn->dir, psn->denttot, rda->entryname);
128 	if (!pdir)
129 		goto out;
130 
131 	if (psbuf_expect_attrs(pb, &va))
132 		goto out;
133 
134 	if (pdir->entry) {
135 		psn_targ = pdir->entry->pn_data;
136 
137 		puffs_setvattr(&pdir->entry->pn_va, &va);
138 		psn_targ->attrread = time(NULL);
139 	} else {
140 		puffs_setvattr(&pdir->va, &va);
141 		pdir->attrread = time(NULL);
142 	}
143 
144  out:
145 	if (psn_targ) {
146 		psn_targ->getattr_pb = NULL;
147 		assert(pdir->getattr_pb == NULL);
148 	} else if (pdir) {
149 		pdir->getattr_pb = NULL;
150 	}
151 
152 	free(rda);
153 	puffs_framebuf_destroy(pb);
154 }
155 
156 static void
157 readdir_getattr(struct puffs_usermount *pu, struct psshfs_node *psn,
158 	const char *basepath, int idx)
159 {
160 	char path[MAXPATHLEN+1];
161 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
162 	struct psshfs_dir *pdir = psn->dir;
163 	struct puffs_framebuf *pb;
164 	struct readdirattr *rda;
165 	const char *entryname = pdir[idx].entryname;
166 	uint32_t reqid = NEXTREQ(pctx);
167 
168 	rda = emalloc(sizeof(struct readdirattr));
169 	rda->psn = psn;
170 	rda->idx = idx;
171 	strlcpy(rda->entryname, entryname, sizeof(rda->entryname));
172 
173 	strcpy(path, basepath);
174 	strcat(path, "/");
175 	strlcat(path, entryname, sizeof(path));
176 
177 	pb = psbuf_makeout();
178 	psbuf_req_str(pb, SSH_FXP_LSTAT, reqid, path);
179 	psn->da[psn->nextda].pufbuf = pb;
180 	psn->da[psn->nextda].rda = rda;
181 	psn->nextda++;
182 }
183 
184 static void
185 readdir_getattr_send(struct puffs_usermount *pu, struct psshfs_node *psn)
186 {
187 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
188 	struct psshfs_dir *pdir = psn->dir;
189 	struct psshfs_node *psn_targ;
190 	struct readdirattr *rda;
191 	size_t i;
192 	int rv = 0;
193 
194 	for (i = 0; i < psn->nextda; i++) {
195 		rda = psn->da[i].rda;
196 		if (pdir[rda->idx].entry) {
197 			psn_targ = pdir[rda->idx].entry->pn_data;
198 			psn_targ->getattr_pb = psn->da[i].pufbuf;
199 		} else {
200 			pdir[rda->idx].getattr_pb = psn->da[i].pufbuf;
201 		}
202 		SENDCB(psn->da[i].pufbuf, readdir_getattr_resp, rda);
203 	}
204 
205  out:
206 	return;
207 }
208 
209 int
210 getpathattr(struct puffs_cc *pcc, const char *path, struct vattr *vap)
211 {
212 	PSSHFSAUTOVAR(pcc);
213 
214 	psbuf_req_str(pb, SSH_FXP_LSTAT, reqid, path);
215 	GETRESPONSE(pb);
216 
217 	rv = psbuf_expect_attrs(pb, vap);
218 
219  out:
220 	PSSHFSRETURN(rv);
221 }
222 
223 int
224 getnodeattr(struct puffs_cc *pcc, struct puffs_node *pn)
225 {
226 	struct puffs_usermount *pu = puffs_cc_getusermount(pcc);
227 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
228 	struct psshfs_node *psn = pn->pn_data;
229 	struct vattr va;
230 	int rv, dohardway;
231 
232 	if (!psn->attrread || REFRESHTIMEOUT(pctx, time(NULL)-psn->attrread)) {
233 		dohardway = 1;
234 		if (psn->getattr_pb) {
235 			rv=puffs_framev_framebuf_ccpromote(psn->getattr_pb,pcc);
236 			if (rv == 0) {
237 				rv = psbuf_expect_attrs(psn->getattr_pb, &va);
238 				puffs_framebuf_destroy(psn->getattr_pb);
239 				psn->getattr_pb = NULL;
240 				if (rv == 0)
241 					dohardway = 0;
242 			}
243 		}
244 
245 		if (dohardway) {
246 			rv = getpathattr(pcc, PNPATH(pn), &va);
247 			if (rv)
248 				return rv;
249 		}
250 
251 		/*
252 		 * Check if the file was modified from below us.
253 		 * If so, invalidate page cache.  This is the only
254 		 * sensible place we can do this in.
255 		 */
256 		if (psn->attrread)
257 			if (pn->pn_va.va_mtime.tv_sec != va.va_mtime.tv_sec)
258 				puffs_inval_pagecache_node(pu, pn);
259 
260 		puffs_setvattr(&pn->pn_va, &va);
261 		psn->attrread = time(NULL);
262 	}
263 
264 	return 0;
265 }
266 
267 int
268 sftp_readdir(struct puffs_cc *pcc, struct psshfs_ctx *pctx,
269 	struct puffs_node *pn)
270 {
271 	struct puffs_usermount *pu = puffs_cc_getusermount(pcc);
272 	struct psshfs_node *psn = pn->pn_data;
273 	struct psshfs_dir *olddir, *testd;
274 	struct puffs_framebuf *pb;
275 	uint32_t reqid = NEXTREQ(pctx);
276 	uint32_t count, dhandlen;
277 	char *dhand = NULL;
278 	size_t nent;
279 	char *longname = NULL;
280 	int idx, rv;
281 
282 	assert(pn->pn_va.va_type == VDIR);
283 	idx = 0;
284 	olddir = psn->dir;
285 	nent = psn->dentnext;
286 
287 	if (psn->dir && psn->dentread
288 	    && !REFRESHTIMEOUT(pctx, time(NULL) - psn->dentread))
289 		return 0;
290 
291 	if ((rv = puffs_inval_namecache_dir(pu, pn)))
292 		warn("readdir: dcache inval fail %p", pn);
293 
294 	pb = psbuf_makeout();
295 	psbuf_req_str(pb, SSH_FXP_OPENDIR, reqid, PNPATH(pn));
296 	if (puffs_framev_enqueue_cc(pcc, pctx->sshfd, pb, 0) == -1) {
297 		rv = errno;
298 		goto wayout;
299 	}
300 	rv = psbuf_expect_handle(pb, &dhand, &dhandlen);
301 	if (rv)
302 		goto wayout;
303 
304 	/*
305 	 * Well, the following is O(n^2), so feel free to improve if it
306 	 * gets too taxing on your system.
307 	 */
308 
309 	/*
310 	 * note: for the "getattr in batch" to work, this must be before
311 	 * the attribute-getting.  Otherwise times for first entries in
312 	 * large directories might expire before the directory itself and
313 	 * result in one-by-one attribute fetching.
314 	 */
315 	psn->dentread = time(NULL);
316 
317 	psn->dentnext = 0;
318 	psn->denttot = 0;
319 	psn->dir = NULL;
320 	psn->nextda = 0;
321 
322 	for (;;) {
323 		reqid = NEXTREQ(pctx);
324 		psbuf_recycleout(pb);
325 		psbuf_req_data(pb, SSH_FXP_READDIR, reqid, dhand, dhandlen);
326 		GETRESPONSE(pb);
327 
328 		/* check for EOF */
329 		if (psbuf_get_type(pb) == SSH_FXP_STATUS) {
330 			rv = psbuf_expect_status(pb);
331 			goto out;
332 		}
333 		rv = psbuf_expect_name(pb, &count);
334 		if (rv)
335 			goto out;
336 
337 		for (; count--; idx++) {
338 			if (idx == psn->denttot)
339 				allocdirs(psn);
340 			if ((rv = psbuf_get_str(pb,
341 			    &psn->dir[idx].entryname, NULL)))
342 				goto out;
343 			if ((rv = psbuf_get_str(pb, &longname, NULL)) != 0)
344 				goto out;
345 			if ((rv = psbuf_get_vattr(pb, &psn->dir[idx].va)) != 0)
346 				goto out;
347 			if (sscanf(longname, "%*s%d",
348 			    &psn->dir[idx].va.va_nlink) != 1) {
349 				rv = EPROTO;
350 				goto out;
351 			}
352 			free(longname);
353 			longname = NULL;
354 
355 			testd = lookup(olddir, nent, psn->dir[idx].entryname);
356 			if (testd) {
357 				psn->dir[idx].entry = testd->entry;
358 				psn->dir[idx].va = testd->va;
359 			} else {
360 				psn->dir[idx].entry = NULL;
361 				psn->dir[idx].va.va_fileid = pctx->nextino++;
362 			}
363 			/*
364 			 * XXX: there's a dangling pointer race here if
365 			 * the server responds to our queries out-of-order.
366 			 * fixxxme some day
367 			 */
368 			readdir_getattr(puffs_cc_getusermount(pcc),
369 			    psn, PNPATH(pn), idx);
370 
371 			psn->dir[idx].valid = 1;
372 		}
373 	}
374 
375  out:
376 	/* fire off getattr requests */
377 	readdir_getattr_send(pu, psn);
378 
379 	/* XXX: rv */
380 	psn->dentnext = idx;
381 	freedircache(olddir, nent);
382 
383 	reqid = NEXTREQ(pctx);
384 	psbuf_recycleout(pb);
385 	psbuf_req_data(pb, SSH_FXP_CLOSE, reqid, dhand, dhandlen);
386 	puffs_framev_enqueue_justsend(pu, pctx->sshfd, pb, 1, 0);
387 	free(dhand);
388 	free(longname);
389 
390 	return rv;
391 
392  wayout:
393 	free(dhand);
394 	PSSHFSRETURN(rv);
395 }
396 
397 struct puffs_node *
398 makenode(struct puffs_usermount *pu, struct puffs_node *parent,
399 	struct psshfs_dir *pd, const struct vattr *vap)
400 {
401 	struct psshfs_node *psn_parent = parent->pn_data;
402 	struct psshfs_node *psn;
403 	struct puffs_node *pn;
404 
405 	psn = emalloc(sizeof(struct psshfs_node));
406 	memset(psn, 0, sizeof(struct psshfs_node));
407 
408 	pn = puffs_pn_new(pu, psn);
409 	if (!pn) {
410 		free(psn);
411 		return NULL;
412 	}
413 	puffs_setvattr(&pn->pn_va, &pd->va);
414 	psn->attrread = pd->attrread;
415 	puffs_setvattr(&pn->pn_va, vap);
416 
417 	pd->entry = pn;
418 	psn->parent = parent;
419 	psn_parent->childcount++;
420 
421 	TAILQ_INIT(&psn->pw);
422 
423 	if (pd->getattr_pb) {
424 		psn->getattr_pb = pd->getattr_pb;
425 		pd->getattr_pb = NULL;
426 	}
427 
428 	return pn;
429 }
430 
431 struct puffs_node *
432 allocnode(struct puffs_usermount *pu, struct puffs_node *parent,
433 	const char *entryname, const struct vattr *vap)
434 {
435 	struct psshfs_ctx *pctx = puffs_getspecific(pu);
436 	struct psshfs_dir *pd;
437 	struct puffs_node *pn;
438 
439 	pd = direnter(parent, entryname);
440 
441 	pd->va.va_fileid = pctx->nextino++;
442 	if (vap->va_type == VDIR) {
443 		pd->va.va_nlink = 2;
444 		parent->pn_va.va_nlink++;
445 	} else {
446 		pd->va.va_nlink = 1;
447 	}
448 
449 	pn = makenode(pu, parent, pd, vap);
450 	if (pn)
451 		pd->va.va_fileid = pn->pn_va.va_fileid;
452 
453 	return pn;
454 }
455 
456 struct psshfs_dir *
457 direnter(struct puffs_node *parent, const char *entryname)
458 {
459 	struct psshfs_node *psn_parent = parent->pn_data;
460 	struct psshfs_dir *pd;
461 	int i;
462 
463 	/* create directory entry */
464 	if (psn_parent->denttot == psn_parent->dentnext)
465 		allocdirs(psn_parent);
466 
467 	i = psn_parent->dentnext;
468 	pd = &psn_parent->dir[i];
469 	pd->entryname = estrdup(entryname);
470 	pd->valid = 1;
471 	pd->attrread = 0;
472 	puffs_vattr_null(&pd->va);
473 	psn_parent->dentnext++;
474 
475 	return pd;
476 }
477 
478 void
479 doreclaim(struct puffs_node *pn)
480 {
481 	struct psshfs_node *psn = pn->pn_data;
482 	struct psshfs_node *psn_parent;
483 	struct psshfs_dir *dent;
484 
485 	psn_parent = psn->parent->pn_data;
486 	psn_parent->childcount--;
487 
488 	/*
489 	 * Null out entry from directory.  Do not treat a missing entry
490 	 * as an invariant error, since the node might be removed from
491 	 * under us, and we might do a readdir before the reclaim resulting
492 	 * in no directory entry in the parent directory.
493 	 */
494 	dent = lookup_by_entry(psn_parent->dir, psn_parent->dentnext, pn);
495 	if (dent)
496 		dent->entry = NULL;
497 
498 	if (pn->pn_va.va_type == VDIR) {
499 		freedircache(psn->dir, psn->dentnext);
500 		psn->denttot = psn->dentnext = 0;
501 		free(psn->da);
502 	}
503 	if (psn->symlink)
504 		free(psn->symlink);
505 
506 	puffs_pn_put(pn);
507 }
508 
509 void
510 nukenode(struct puffs_node *node, const char *entryname, int reclaim)
511 {
512 	struct psshfs_node *psn, *psn_parent;
513 	struct psshfs_dir *pd;
514 
515 	psn = node->pn_data;
516 	psn_parent = psn->parent->pn_data;
517 	pd = lookup(psn_parent->dir, psn_parent->dentnext, entryname);
518 	assert(pd != NULL);
519 	pd->valid = 0;
520 	free(pd->entryname);
521 	pd->entryname = NULL;
522 
523 	if (node->pn_va.va_type == VDIR)
524 		psn->parent->pn_va.va_nlink--;
525 
526 	if (reclaim)
527 		doreclaim(node);
528 }
529