2 * Copyright (c) 2008 Sean C. Farley <scf@FreeBSD.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer,
10 * without modification, immediately at the beginning of the file.
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.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/errno.h>
47 static int lockfd = -1;
48 static char group_dir[PATH_MAX];
49 static char group_file[PATH_MAX];
50 static char tempname[PATH_MAX];
51 static int initialized;
57 gr_init(const char *dir, const char *group)
61 strcpy(group_dir, _PATH_ETC);
63 if (strlen(dir) >= sizeof(group_dir)) {
67 strcpy(group_dir, dir);
72 strcpy(group_file, _PATH_GROUP);
73 } else if (snprintf(group_file, sizeof(group_file), "%s/group",
74 group_dir) > (int)sizeof(group_file)) {
79 if (strlen(group) >= sizeof(group_file)) {
83 strcpy(group_file, group);
96 if (*group_file == '\0')
102 lockfd = flopen(group_file, O_RDONLY|O_NONBLOCK|O_CLOEXEC, 0);
104 if (errno == EWOULDBLOCK) {
105 errx(1, "the group file is busy");
107 err(1, "could not lock the group file: ");
110 if (fstat(lockfd, &st) == -1)
111 err(1, "fstat() failed: ");
112 if (st.st_nlink != 0)
121 * Create and open a presmuably safe temp file for editing group data
131 if (*group_file == '\0')
133 if ((p = strrchr(group_file, '/')))
137 if (snprintf(tempname, sizeof(tempname), "%.*sgroup.XXXXXX",
138 (int)(p - group_file), group_file) >= (int)sizeof(tempname)) {
139 errno = ENAMETOOLONG;
142 if ((tfd = mkstemp(tempname)) == -1)
145 while ((nr = read(mfd, buf, sizeof(buf))) > 0)
146 if (write(tfd, buf, (size_t)nr) != nr)
159 * Copy the group file from one descriptor to another, replacing, deleting
160 * or adding a single record on the way.
163 gr_copy(int ffd, int tfd, const struct group *gr, struct group *old_gr)
165 char buf[8192], *end, *line, *p, *q, *r, t;
167 const struct group *sgr;
177 } else if ((line = gr_make(gr)) == NULL)
184 /* find the end of the current line */
185 for (p = q; q < end && *q != '\0'; ++q)
189 /* if we don't have a complete line, fill up the buffer */
193 if ((size_t)(q - p) >= sizeof(buf)) {
194 warnx("group line too long");
195 errno = EINVAL; /* hack */
199 q = memmove(buf, p, end -p);
204 readlen = read(ffd, end, sizeof(buf) - (end -buf));
208 len = (size_t)readlen;
209 if (len == 0 && p == buf)
213 if (len < (ssize_t)sizeof(buf)) {
215 if (len > 0 && buf[len -1] != '\n')
216 ++len, *end++ = '\n';
221 /* is it a blank line or a comment? */
222 for (r = p; r < q && isspace(*r); ++r)
224 if (r == q || *r == '#') {
226 if (write(tfd, p, q -p + 1) != q - p + 1)
232 /* is it the one we're looking for? */
239 /* fgr is either a struct group for the current line,
240 * or NULL if the line is malformed.
244 if (fgr == NULL || fgr->gr_gid != sgr->gr_gid) {
248 if (write(tfd, p, q - p + 1) != q - p + 1)
253 if (old_gr && !gr_equal(fgr, old_gr)) {
254 warnx("entry inconsistent");
256 errno = EINVAL; /* hack */
261 /* it is, replace or remove it */
264 if (write(tfd, line, len) != (int) len)
267 /* when removed, avoid the \n */
270 /* we're done, just copy the rest over */
272 if (write(tfd, q, end - q) != end - q)
275 readlen = read(ffd, buf, sizeof(buf));
279 len = (size_t)readlen;
287 /* if we got here, we didn't find the old entry */
293 if ((size_t)write(tfd, line, len) != len ||
294 write(tfd, "\n", 1) != 1)
307 * Regenerate the group file
312 if (chmod(tempname, 0644) != 0)
315 return (rename(tempname, group_file));
319 * Clean up. Preserves errno for the caller's convenience.
330 if (*tempname != '\0') {
340 * Compares two struct group's.
343 gr_equal(const struct group *gr1, const struct group *gr2)
348 /* Check that the non-member information is the same. */
349 if (gr1->gr_name == NULL || gr2->gr_name == NULL) {
350 if (gr1->gr_name != gr2->gr_name)
352 } else if (strcmp(gr1->gr_name, gr2->gr_name) != 0)
354 if (gr1->gr_passwd == NULL || gr2->gr_passwd == NULL) {
355 if (gr1->gr_passwd != gr2->gr_passwd)
357 } else if (strcmp(gr1->gr_passwd, gr2->gr_passwd) != 0)
359 if (gr1->gr_gid != gr2->gr_gid)
362 /* Check all members in both groups. */
363 if (gr1->gr_mem == NULL || gr2->gr_mem == NULL) {
364 if (gr1->gr_mem != gr2->gr_mem)
367 for (gr1_ndx = 0; gr1->gr_mem[gr1_ndx] != NULL; gr1_ndx++) {
368 for (gr2_ndx = 0;; gr2_ndx++) {
369 if (gr2->gr_mem[gr2_ndx] == NULL)
371 if (strcmp(gr1->gr_mem[gr1_ndx],
372 gr2->gr_mem[gr2_ndx]) == 0) {
378 /* Check that group2 does not have more members than group1. */
379 if (gr2->gr_mem[gr1_ndx] != NULL)
387 * Make a group line out of a struct group.
390 gr_make(const struct group *gr)
392 const char *group_line_format = "%s:%s:%ju:";
399 /* Calculate the length of the group line. */
400 line_size = snprintf(NULL, 0, group_line_format, gr->gr_name,
401 gr->gr_passwd, (uintmax_t)gr->gr_gid) + 1;
402 if (gr->gr_mem != NULL) {
403 for (ndx = 0; gr->gr_mem[ndx] != NULL; ndx++)
404 line_size += strlen(gr->gr_mem[ndx]) + 1;
409 /* Create the group line and fill it. */
410 if ((line = p = malloc(line_size)) == NULL)
412 p += sprintf(p, group_line_format, gr->gr_name, gr->gr_passwd,
413 (uintmax_t)gr->gr_gid);
414 if (gr->gr_mem != NULL) {
416 for (ndx = 0; gr->gr_mem[ndx] != NULL; ndx++) {
418 p = stpcpy(p, gr->gr_mem[ndx]);
427 * Duplicate a struct group.
430 gr_dup(const struct group *gr)
438 /* Calculate size of the group. */
439 len = sizeof(*newgr);
440 if (gr->gr_name != NULL)
441 len += strlen(gr->gr_name) + 1;
442 if (gr->gr_passwd != NULL)
443 len += strlen(gr->gr_passwd) + 1;
444 if (gr->gr_mem != NULL) {
445 for (num_mem = 0; gr->gr_mem[num_mem] != NULL; num_mem++)
446 len += strlen(gr->gr_mem[num_mem]) + 1;
447 len += (num_mem + 1) * sizeof(*gr->gr_mem);
450 /* Create new group and copy old group into it. */
451 if ((newgr = malloc(len)) == NULL)
453 /* point new gr_mem to end of struct + 1 */
454 if (gr->gr_mem != NULL)
455 newgr->gr_mem = (char **)(newgr + 1);
457 newgr->gr_mem = NULL;
458 /* point dst after the end of all the gr_mem pointers in newgr */
459 dst = (char *)&newgr->gr_mem[num_mem + 1];
460 if (gr->gr_name != NULL) {
461 newgr->gr_name = dst;
462 dst = stpcpy(dst, gr->gr_name) + 1;
464 newgr->gr_name = NULL;
466 if (gr->gr_passwd != NULL) {
467 newgr->gr_passwd = dst;
468 dst = stpcpy(dst, gr->gr_passwd) + 1;
470 newgr->gr_passwd = NULL;
472 newgr->gr_gid = gr->gr_gid;
473 if (gr->gr_mem != NULL) {
474 for (ndx = 0; ndx < num_mem; ndx++) {
475 newgr->gr_mem[ndx] = dst;
476 dst = stpcpy(dst, gr->gr_mem[ndx]) + 1;
478 newgr->gr_mem[ndx] = NULL;
484 * Add a new member name to a struct group.
487 gr_add(struct group *gr, char *newmember)
494 if (newmember == NULL)
497 if (gr->gr_mem != NULL) {
498 for (num_mem = 0; gr->gr_mem[num_mem] != NULL; num_mem++) {
499 if (strcmp(gr->gr_mem[num_mem], newmember) == 0) {
505 /* Allocate enough for current pointers + 1 more and NULL marker */
506 mlen = (num_mem + 2) * sizeof(*gr->gr_mem);
507 if ((members = malloc(mlen)) == NULL)
509 memcpy(members, gr->gr_mem, num_mem * sizeof(*gr->gr_mem));
510 members[num_mem++] = newmember;
511 members[num_mem] = NULL;
512 gr->gr_mem = members;
519 * Scan a line and place it into a group structure.
522 __gr_scan(char *line, struct group *gr)
527 /* Assign non-member information to structure. */
529 if ((loc = strchr(line, ':')) == NULL)
532 gr->gr_passwd = loc + 1;
533 if (*gr->gr_passwd == ':')
534 *gr->gr_passwd = '\0';
536 if ((loc = strchr(loc + 1, ':')) == NULL)
540 if (sscanf(loc + 1, "%u", &gr->gr_gid) != 1)
543 /* Assign member information to structure. */
544 if ((loc = strchr(loc + 1, ':')) == NULL)
550 gr->gr_mem = reallocf(gr->gr_mem, sizeof(*gr->gr_mem) *
552 if (gr->gr_mem == NULL)
555 /* Skip locations without members (i.e., empty string). */
557 gr->gr_mem[ndx] = strsep(&line, ",");
558 } while (gr->gr_mem[ndx] != NULL && *gr->gr_mem[ndx] == '\0');
559 } while (gr->gr_mem[ndx++] != NULL);
565 * Create a struct group from a line.
568 gr_scan(const char *line)
572 struct group *new_gr;
574 if ((line_copy = strdup(line)) == NULL)
576 if (!__gr_scan(line_copy, &gr)) {
580 new_gr = gr_dup(&gr);
582 if (gr.gr_mem != NULL)