xref: /freebsd/lib/libutil/quotafile.c (revision d0b2dbfa)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2008 Dag-Erling Coïdan Smørgrav
5  * Copyright (c) 2008 Marshall Kirk McKusick
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer
13  *    in this position and unchanged.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/types.h>
32 #include <sys/endian.h>
33 #include <sys/mount.h>
34 #include <sys/stat.h>
35 
36 #include <ufs/ufs/quota.h>
37 
38 #include <errno.h>
39 #include <fcntl.h>
40 #include <fstab.h>
41 #include <grp.h>
42 #include <pwd.h>
43 #include <libutil.h>
44 #include <stdint.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 struct quotafile {
51 	int fd;				/* -1 means using quotactl for access */
52 	int accmode;			/* access mode */
53 	int wordsize;			/* 32-bit or 64-bit limits */
54 	int quotatype;			/* USRQUOTA or GRPQUOTA */
55 	dev_t dev;			/* device */
56 	char fsname[MAXPATHLEN + 1];	/* mount point of filesystem */
57 	char qfname[MAXPATHLEN + 1];	/* quota file if not using quotactl */
58 };
59 
60 static const char *qfextension[] = INITQFNAMES;
61 
62 /*
63  * Check to see if a particular quota is to be enabled.
64  */
65 static int
66 hasquota(struct fstab *fs, int type, char *qfnamep, int qfbufsize)
67 {
68 	char *opt;
69 	char *cp;
70 	struct statfs sfb;
71 	char buf[BUFSIZ];
72 	static char initname, usrname[100], grpname[100];
73 
74 	/*
75 	 * 1) we only need one of these
76 	 * 2) fstab may specify a different filename
77 	 */
78 	if (!initname) {
79 		(void)snprintf(usrname, sizeof(usrname), "%s%s",
80 		    qfextension[USRQUOTA], QUOTAFILENAME);
81 		(void)snprintf(grpname, sizeof(grpname), "%s%s",
82 		    qfextension[GRPQUOTA], QUOTAFILENAME);
83 		initname = 1;
84 	}
85 	strcpy(buf, fs->fs_mntops);
86 	for (opt = strtok(buf, ","); opt; opt = strtok(NULL, ",")) {
87 		if ((cp = strchr(opt, '=')))
88 			*cp++ = '\0';
89 		if (type == USRQUOTA && strcmp(opt, usrname) == 0)
90 			break;
91 		if (type == GRPQUOTA && strcmp(opt, grpname) == 0)
92 			break;
93 	}
94 	if (!opt)
95 		return (0);
96 	/*
97 	 * Ensure that the filesystem is mounted.
98 	 */
99 	if (statfs(fs->fs_file, &sfb) != 0 ||
100 	    strcmp(fs->fs_file, sfb.f_mntonname)) {
101 		return (0);
102 	}
103 	if (cp) {
104 		strlcpy(qfnamep, cp, qfbufsize);
105 	} else {
106 		(void)snprintf(qfnamep, qfbufsize, "%s/%s.%s", fs->fs_file,
107 		    QUOTAFILENAME, qfextension[type]);
108 	}
109 	return (1);
110 }
111 
112 struct quotafile *
113 quota_open(struct fstab *fs, int quotatype, int openflags)
114 {
115 	struct quotafile *qf;
116 	struct dqhdr64 dqh;
117 	struct group *grp;
118 	struct stat st;
119 	int qcmd, serrno = 0;
120 	int ufs;
121 
122 	if ((qf = calloc(1, sizeof(*qf))) == NULL)
123 		return (NULL);
124 	qf->fd = -1;
125 	qf->quotatype = quotatype;
126 	strlcpy(qf->fsname, fs->fs_file, sizeof(qf->fsname));
127 	if (stat(qf->fsname, &st) != 0)
128 		goto error;
129 	qf->dev = st.st_dev;
130 	qcmd = QCMD(Q_GETQUOTASIZE, quotatype);
131 	ufs = strcmp(fs->fs_vfstype, "ufs") == 0;
132 	/*
133 	 * On UFS, hasquota() fills in qf->qfname. But we only care about
134 	 * this for UFS.  So we need to call hasquota() for UFS, first.
135 	 */
136 	if (ufs) {
137 		serrno = hasquota(fs, quotatype, qf->qfname,
138 		    sizeof(qf->qfname));
139 	}
140 	if (quotactl(qf->fsname, qcmd, 0, &qf->wordsize) == 0)
141 		return (qf);
142 	if (!ufs) {
143 		errno = 0;
144 		goto error;
145 	} else if (serrno == 0) {
146 		errno = EOPNOTSUPP;
147 		goto error;
148 	}
149 	qf->accmode = openflags & O_ACCMODE;
150 	if ((qf->fd = open(qf->qfname, qf->accmode|O_CLOEXEC)) < 0 &&
151 	    (openflags & O_CREAT) != O_CREAT)
152 		goto error;
153 	/* File open worked, so process it */
154 	if (qf->fd != -1) {
155 		qf->wordsize = 32;
156 		switch (read(qf->fd, &dqh, sizeof(dqh))) {
157 		case -1:
158 			goto error;
159 		case sizeof(dqh):
160 			if (strcmp(dqh.dqh_magic, Q_DQHDR64_MAGIC) != 0) {
161 				/* no magic, assume 32 bits */
162 				qf->wordsize = 32;
163 				return (qf);
164 			}
165 			if (be32toh(dqh.dqh_version) != Q_DQHDR64_VERSION ||
166 			    be32toh(dqh.dqh_hdrlen) != sizeof(struct dqhdr64) ||
167 			    be32toh(dqh.dqh_reclen) != sizeof(struct dqblk64)) {
168 				/* correct magic, wrong version / lengths */
169 				errno = EINVAL;
170 				goto error;
171 			}
172 			qf->wordsize = 64;
173 			return (qf);
174 		default:
175 			qf->wordsize = 32;
176 			return (qf);
177 		}
178 		/* not reached */
179 	}
180 	/* open failed, but O_CREAT was specified, so create a new file */
181 	if ((qf->fd = open(qf->qfname, O_RDWR|O_CREAT|O_TRUNC|O_CLOEXEC, 0)) <
182 	    0)
183 		goto error;
184 	qf->wordsize = 64;
185 	memset(&dqh, 0, sizeof(dqh));
186 	memcpy(dqh.dqh_magic, Q_DQHDR64_MAGIC, sizeof(dqh.dqh_magic));
187 	dqh.dqh_version = htobe32(Q_DQHDR64_VERSION);
188 	dqh.dqh_hdrlen = htobe32(sizeof(struct dqhdr64));
189 	dqh.dqh_reclen = htobe32(sizeof(struct dqblk64));
190 	if (write(qf->fd, &dqh, sizeof(dqh)) != sizeof(dqh)) {
191 		/* it was one we created ourselves */
192 		unlink(qf->qfname);
193 		goto error;
194 	}
195 	grp = getgrnam(QUOTAGROUP);
196 	fchown(qf->fd, 0, grp ? grp->gr_gid : 0);
197 	fchmod(qf->fd, 0640);
198 	return (qf);
199 error:
200 	serrno = errno;
201 	/* did we have an open file? */
202 	if (qf->fd != -1)
203 		close(qf->fd);
204 	free(qf);
205 	errno = serrno;
206 	return (NULL);
207 }
208 
209 void
210 quota_close(struct quotafile *qf)
211 {
212 
213 	if (qf->fd != -1)
214 		close(qf->fd);
215 	free(qf);
216 }
217 
218 int
219 quota_on(struct quotafile *qf)
220 {
221 	int qcmd;
222 
223 	qcmd = QCMD(Q_QUOTAON, qf->quotatype);
224 	return (quotactl(qf->fsname, qcmd, 0, qf->qfname));
225 }
226 
227 int
228 quota_off(struct quotafile *qf)
229 {
230 
231 	return (quotactl(qf->fsname, QCMD(Q_QUOTAOFF, qf->quotatype), 0, 0));
232 }
233 
234 const char *
235 quota_fsname(const struct quotafile *qf)
236 {
237 
238 	return (qf->fsname);
239 }
240 
241 const char *
242 quota_qfname(const struct quotafile *qf)
243 {
244 
245 	return (qf->qfname);
246 }
247 
248 int
249 quota_check_path(const struct quotafile *qf, const char *path)
250 {
251 	struct stat st;
252 
253 	if (stat(path, &st) == -1)
254 		return (-1);
255 	return (st.st_dev == qf->dev);
256 }
257 
258 int
259 quota_maxid(struct quotafile *qf)
260 {
261 	struct stat st;
262 	int maxid;
263 
264 	if (stat(qf->qfname, &st) < 0)
265 		return (0);
266 	switch (qf->wordsize) {
267 	case 32:
268 		maxid = st.st_size / sizeof(struct dqblk32) - 1;
269 		break;
270 	case 64:
271 		maxid = st.st_size / sizeof(struct dqblk64) - 2;
272 		break;
273 	default:
274 		maxid = 0;
275 		break;
276 	}
277 	return (maxid > 0 ? maxid : 0);
278 }
279 
280 static int
281 quota_read32(struct quotafile *qf, struct dqblk *dqb, int id)
282 {
283 	struct dqblk32 dqb32;
284 	off_t off;
285 
286 	off = id * sizeof(struct dqblk32);
287 	if (lseek(qf->fd, off, SEEK_SET) == -1)
288 		return (-1);
289 	switch (read(qf->fd, &dqb32, sizeof(dqb32))) {
290 	case 0:
291 		memset(dqb, 0, sizeof(*dqb));
292 		return (0);
293 	case sizeof(dqb32):
294 		dqb->dqb_bhardlimit = dqb32.dqb_bhardlimit;
295 		dqb->dqb_bsoftlimit = dqb32.dqb_bsoftlimit;
296 		dqb->dqb_curblocks = dqb32.dqb_curblocks;
297 		dqb->dqb_ihardlimit = dqb32.dqb_ihardlimit;
298 		dqb->dqb_isoftlimit = dqb32.dqb_isoftlimit;
299 		dqb->dqb_curinodes = dqb32.dqb_curinodes;
300 		dqb->dqb_btime = dqb32.dqb_btime;
301 		dqb->dqb_itime = dqb32.dqb_itime;
302 		return (0);
303 	default:
304 		return (-1);
305 	}
306 }
307 
308 static int
309 quota_read64(struct quotafile *qf, struct dqblk *dqb, int id)
310 {
311 	struct dqblk64 dqb64;
312 	off_t off;
313 
314 	off = sizeof(struct dqhdr64) + id * sizeof(struct dqblk64);
315 	if (lseek(qf->fd, off, SEEK_SET) == -1)
316 		return (-1);
317 	switch (read(qf->fd, &dqb64, sizeof(dqb64))) {
318 	case 0:
319 		memset(dqb, 0, sizeof(*dqb));
320 		return (0);
321 	case sizeof(dqb64):
322 		dqb->dqb_bhardlimit = be64toh(dqb64.dqb_bhardlimit);
323 		dqb->dqb_bsoftlimit = be64toh(dqb64.dqb_bsoftlimit);
324 		dqb->dqb_curblocks = be64toh(dqb64.dqb_curblocks);
325 		dqb->dqb_ihardlimit = be64toh(dqb64.dqb_ihardlimit);
326 		dqb->dqb_isoftlimit = be64toh(dqb64.dqb_isoftlimit);
327 		dqb->dqb_curinodes = be64toh(dqb64.dqb_curinodes);
328 		dqb->dqb_btime = be64toh(dqb64.dqb_btime);
329 		dqb->dqb_itime = be64toh(dqb64.dqb_itime);
330 		return (0);
331 	default:
332 		return (-1);
333 	}
334 }
335 
336 int
337 quota_read(struct quotafile *qf, struct dqblk *dqb, int id)
338 {
339 	int qcmd;
340 
341 	if (qf->fd == -1) {
342 		qcmd = QCMD(Q_GETQUOTA, qf->quotatype);
343 		return (quotactl(qf->fsname, qcmd, id, dqb));
344 	}
345 	switch (qf->wordsize) {
346 	case 32:
347 		return (quota_read32(qf, dqb, id));
348 	case 64:
349 		return (quota_read64(qf, dqb, id));
350 	default:
351 		errno = EINVAL;
352 		return (-1);
353 	}
354 	/* not reached */
355 }
356 
357 #define CLIP32(u64) ((u64) > UINT32_MAX ? UINT32_MAX : (uint32_t)(u64))
358 
359 static int
360 quota_write32(struct quotafile *qf, const struct dqblk *dqb, int id)
361 {
362 	struct dqblk32 dqb32;
363 	off_t off;
364 
365 	dqb32.dqb_bhardlimit = CLIP32(dqb->dqb_bhardlimit);
366 	dqb32.dqb_bsoftlimit = CLIP32(dqb->dqb_bsoftlimit);
367 	dqb32.dqb_curblocks = CLIP32(dqb->dqb_curblocks);
368 	dqb32.dqb_ihardlimit = CLIP32(dqb->dqb_ihardlimit);
369 	dqb32.dqb_isoftlimit = CLIP32(dqb->dqb_isoftlimit);
370 	dqb32.dqb_curinodes = CLIP32(dqb->dqb_curinodes);
371 	dqb32.dqb_btime = CLIP32(dqb->dqb_btime);
372 	dqb32.dqb_itime = CLIP32(dqb->dqb_itime);
373 
374 	off = id * sizeof(struct dqblk32);
375 	if (lseek(qf->fd, off, SEEK_SET) == -1)
376 		return (-1);
377 	if (write(qf->fd, &dqb32, sizeof(dqb32)) == sizeof(dqb32))
378 		return (0);
379 	return (-1);
380 }
381 
382 static int
383 quota_write64(struct quotafile *qf, const struct dqblk *dqb, int id)
384 {
385 	struct dqblk64 dqb64;
386 	off_t off;
387 
388 	dqb64.dqb_bhardlimit = htobe64(dqb->dqb_bhardlimit);
389 	dqb64.dqb_bsoftlimit = htobe64(dqb->dqb_bsoftlimit);
390 	dqb64.dqb_curblocks = htobe64(dqb->dqb_curblocks);
391 	dqb64.dqb_ihardlimit = htobe64(dqb->dqb_ihardlimit);
392 	dqb64.dqb_isoftlimit = htobe64(dqb->dqb_isoftlimit);
393 	dqb64.dqb_curinodes = htobe64(dqb->dqb_curinodes);
394 	dqb64.dqb_btime = htobe64(dqb->dqb_btime);
395 	dqb64.dqb_itime = htobe64(dqb->dqb_itime);
396 
397 	off = sizeof(struct dqhdr64) + id * sizeof(struct dqblk64);
398 	if (lseek(qf->fd, off, SEEK_SET) == -1)
399 		return (-1);
400 	if (write(qf->fd, &dqb64, sizeof(dqb64)) == sizeof(dqb64))
401 		return (0);
402 	return (-1);
403 }
404 
405 int
406 quota_write_usage(struct quotafile *qf, struct dqblk *dqb, int id)
407 {
408 	struct dqblk dqbuf;
409 	int qcmd;
410 
411 	if (qf->fd == -1) {
412 		qcmd = QCMD(Q_SETUSE, qf->quotatype);
413 		return (quotactl(qf->fsname, qcmd, id, dqb));
414 	}
415 	/*
416 	 * Have to do read-modify-write of quota in file.
417 	 */
418 	if ((qf->accmode & O_RDWR) != O_RDWR) {
419 		errno = EBADF;
420 		return (-1);
421 	}
422 	if (quota_read(qf, &dqbuf, id) != 0)
423 		return (-1);
424 	/*
425 	 * Reset time limit if have a soft limit and were
426 	 * previously under it, but are now over it.
427 	 */
428 	if (dqbuf.dqb_bsoftlimit && id != 0 &&
429 	    dqbuf.dqb_curblocks < dqbuf.dqb_bsoftlimit &&
430 	    dqb->dqb_curblocks >= dqbuf.dqb_bsoftlimit)
431 		dqbuf.dqb_btime = 0;
432 	if (dqbuf.dqb_isoftlimit && id != 0 &&
433 	    dqbuf.dqb_curinodes < dqbuf.dqb_isoftlimit &&
434 	    dqb->dqb_curinodes >= dqbuf.dqb_isoftlimit)
435 		dqbuf.dqb_itime = 0;
436 	dqbuf.dqb_curinodes = dqb->dqb_curinodes;
437 	dqbuf.dqb_curblocks = dqb->dqb_curblocks;
438 	/*
439 	 * Write it back.
440 	 */
441 	switch (qf->wordsize) {
442 	case 32:
443 		return (quota_write32(qf, &dqbuf, id));
444 	case 64:
445 		return (quota_write64(qf, &dqbuf, id));
446 	default:
447 		errno = EINVAL;
448 		return (-1);
449 	}
450 	/* not reached */
451 }
452 
453 int
454 quota_write_limits(struct quotafile *qf, struct dqblk *dqb, int id)
455 {
456 	struct dqblk dqbuf;
457 	int qcmd;
458 
459 	if (qf->fd == -1) {
460 		qcmd = QCMD(Q_SETQUOTA, qf->quotatype);
461 		return (quotactl(qf->fsname, qcmd, id, dqb));
462 	}
463 	/*
464 	 * Have to do read-modify-write of quota in file.
465 	 */
466 	if ((qf->accmode & O_RDWR) != O_RDWR) {
467 		errno = EBADF;
468 		return (-1);
469 	}
470 	if (quota_read(qf, &dqbuf, id) != 0)
471 		return (-1);
472 	/*
473 	 * Reset time limit if have a soft limit and were
474 	 * previously under it, but are now over it
475 	 * or if there previously was no soft limit, but
476 	 * now have one and are over it.
477 	 */
478 	if (dqbuf.dqb_bsoftlimit && id != 0 &&
479 	    dqbuf.dqb_curblocks < dqbuf.dqb_bsoftlimit &&
480 	    dqbuf.dqb_curblocks >= dqb->dqb_bsoftlimit)
481 		dqb->dqb_btime = 0;
482 	if (dqbuf.dqb_bsoftlimit == 0 && id != 0 &&
483 	    dqb->dqb_bsoftlimit > 0 &&
484 	    dqbuf.dqb_curblocks >= dqb->dqb_bsoftlimit)
485 		dqb->dqb_btime = 0;
486 	if (dqbuf.dqb_isoftlimit && id != 0 &&
487 	    dqbuf.dqb_curinodes < dqbuf.dqb_isoftlimit &&
488 	    dqbuf.dqb_curinodes >= dqb->dqb_isoftlimit)
489 		dqb->dqb_itime = 0;
490 	if (dqbuf.dqb_isoftlimit == 0 && id !=0 &&
491 	    dqb->dqb_isoftlimit > 0 &&
492 	    dqbuf.dqb_curinodes >= dqb->dqb_isoftlimit)
493 		dqb->dqb_itime = 0;
494 	dqb->dqb_curinodes = dqbuf.dqb_curinodes;
495 	dqb->dqb_curblocks = dqbuf.dqb_curblocks;
496 	/*
497 	 * Write it back.
498 	 */
499 	switch (qf->wordsize) {
500 	case 32:
501 		return (quota_write32(qf, dqb, id));
502 	case 64:
503 		return (quota_write64(qf, dqb, id));
504 	default:
505 		errno = EINVAL;
506 		return (-1);
507 	}
508 	/* not reached */
509 }
510 
511 /*
512  * Convert a quota file from one format to another.
513  */
514 int
515 quota_convert(struct quotafile *qf, int wordsize)
516 {
517 	struct quotafile *newqf;
518 	struct dqhdr64 dqh;
519 	struct dqblk dqblk;
520 	struct group *grp;
521 	int serrno, maxid, id, fd;
522 
523 	/*
524 	 * Quotas must not be active and quotafile must be open
525 	 * for reading and writing.
526 	 */
527 	if ((qf->accmode & O_RDWR) != O_RDWR || qf->fd == -1) {
528 		errno = EBADF;
529 		return (-1);
530 	}
531 	if ((wordsize != 32 && wordsize != 64) ||
532 	     wordsize == qf->wordsize) {
533 		errno = EINVAL;
534 		return (-1);
535 	}
536 	maxid = quota_maxid(qf);
537 	if ((newqf = calloc(1, sizeof(*qf))) == NULL) {
538 		errno = ENOMEM;
539 		return (-1);
540 	}
541 	*newqf = *qf;
542 	snprintf(newqf->qfname, MAXPATHLEN + 1, "%s_%d.orig", qf->qfname,
543 	    qf->wordsize);
544 	if (rename(qf->qfname, newqf->qfname) < 0) {
545 		free(newqf);
546 		return (-1);
547 	}
548 	if ((newqf->fd = open(qf->qfname, O_RDWR|O_CREAT|O_TRUNC|O_CLOEXEC,
549 	    0)) < 0) {
550 		serrno = errno;
551 		goto error;
552 	}
553 	newqf->wordsize = wordsize;
554 	if (wordsize == 64) {
555 		memset(&dqh, 0, sizeof(dqh));
556 		memcpy(dqh.dqh_magic, Q_DQHDR64_MAGIC, sizeof(dqh.dqh_magic));
557 		dqh.dqh_version = htobe32(Q_DQHDR64_VERSION);
558 		dqh.dqh_hdrlen = htobe32(sizeof(struct dqhdr64));
559 		dqh.dqh_reclen = htobe32(sizeof(struct dqblk64));
560 		if (write(newqf->fd, &dqh, sizeof(dqh)) != sizeof(dqh)) {
561 			serrno = errno;
562 			goto error;
563 		}
564 	}
565 	grp = getgrnam(QUOTAGROUP);
566 	fchown(newqf->fd, 0, grp ? grp->gr_gid : 0);
567 	fchmod(newqf->fd, 0640);
568 	for (id = 0; id <= maxid; id++) {
569 		if ((quota_read(qf, &dqblk, id)) < 0)
570 			break;
571 		switch (newqf->wordsize) {
572 		case 32:
573 			if ((quota_write32(newqf, &dqblk, id)) < 0)
574 				break;
575 			continue;
576 		case 64:
577 			if ((quota_write64(newqf, &dqblk, id)) < 0)
578 				break;
579 			continue;
580 		default:
581 			errno = EINVAL;
582 			break;
583 		}
584 	}
585 	if (id < maxid) {
586 		serrno = errno;
587 		goto error;
588 	}
589 	/*
590 	 * Update the passed in quotafile to reference the new file
591 	 * of the converted format size.
592 	 */
593 	fd = qf->fd;
594 	qf->fd = newqf->fd;
595 	newqf->fd = fd;
596 	qf->wordsize = newqf->wordsize;
597 	quota_close(newqf);
598 	return (0);
599 error:
600 	/* put back the original file */
601 	(void) rename(newqf->qfname, qf->qfname);
602 	quota_close(newqf);
603 	errno = serrno;
604 	return (-1);
605 }
606