pw_group.c revision 176474 
1/*-
2 * Copyright (C) 1996
3 *	David L. Nugent.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL DAVID L. NUGENT OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#ifndef lint
28static const char rcsid[] =
29  "$FreeBSD: head/usr.sbin/pw/pw_group.c 176474 2008-02-23 01:25:22Z scf $";
30#endif /* not lint */
31
32#include <ctype.h>
33#include <err.h>
34#include <termios.h>
35#include <stdbool.h>
36#include <unistd.h>
37
38#include "pw.h"
39#include "bitmap.h"
40
41
42static struct passwd *lookup_pwent(const char *user);
43static void	delete_members(char ***members, int *grmembers, int *i,
44    struct carg *arg, struct group *grp);
45static int      print_group(struct group * grp, int pretty);
46static gid_t    gr_gidpolicy(struct userconf * cnf, struct cargs * args);
47
48int
49pw_group(struct userconf * cnf, int mode, struct cargs * args)
50{
51	int		rc;
52	struct carg    *a_name = getarg(args, 'n');
53	struct carg    *a_gid = getarg(args, 'g');
54	struct carg    *arg;
55	struct group   *grp = NULL;
56	int	        grmembers = 0;
57	char           **members = NULL;
58
59	static struct group fakegroup =
60	{
61		"nogroup",
62		"*",
63		-1,
64		NULL
65	};
66
67	if (mode == M_LOCK || mode == M_UNLOCK)
68		errx(EX_USAGE, "'lock' command is not available for groups");
69
70	/*
71	 * With M_NEXT, we only need to return the
72	 * next gid to stdout
73	 */
74	if (mode == M_NEXT) {
75		gid_t next = gr_gidpolicy(cnf, args);
76		if (getarg(args, 'q'))
77			return next;
78		printf("%ld\n", (long)next);
79		return EXIT_SUCCESS;
80	}
81
82	if (mode == M_PRINT && getarg(args, 'a')) {
83		int             pretty = getarg(args, 'P') != NULL;
84
85		SETGRENT();
86		while ((grp = GETGRENT()) != NULL)
87			print_group(grp, pretty);
88		ENDGRENT();
89		return EXIT_SUCCESS;
90	}
91	if (a_gid == NULL) {
92		if (a_name == NULL)
93			errx(EX_DATAERR, "group name or id required");
94
95		if (mode != M_ADD && grp == NULL && isdigit((unsigned char)*a_name->val)) {
96			(a_gid = a_name)->ch = 'g';
97			a_name = NULL;
98		}
99	}
100	grp = (a_name != NULL) ? GETGRNAM(a_name->val) : GETGRGID((gid_t) atoi(a_gid->val));
101
102	if (mode == M_UPDATE || mode == M_DELETE || mode == M_PRINT) {
103		if (a_name == NULL && grp == NULL)	/* Try harder */
104			grp = GETGRGID(atoi(a_gid->val));
105
106		if (grp == NULL) {
107			if (mode == M_PRINT && getarg(args, 'F')) {
108				char	*fmems[1];
109				fmems[0] = NULL;
110				fakegroup.gr_name = a_name ? a_name->val : "nogroup";
111				fakegroup.gr_gid = a_gid ? (gid_t) atol(a_gid->val) : -1;
112				fakegroup.gr_mem = fmems;
113				return print_group(&fakegroup, getarg(args, 'P') != NULL);
114			}
115			errx(EX_DATAERR, "unknown group `%s'", a_name ? a_name->val : a_gid->val);
116		}
117		if (a_name == NULL)	/* Needed later */
118			a_name = addarg(args, 'n', grp->gr_name);
119
120		/*
121		 * Handle deletions now
122		 */
123		if (mode == M_DELETE) {
124			gid_t           gid = grp->gr_gid;
125
126			rc = delgrent(grp);
127			if (rc == -1)
128				err(EX_IOERR, "group '%s' not available (NIS?)", grp->gr_name);
129			else if (rc != 0) {
130				warn("group update");
131				return EX_IOERR;
132			}
133			pw_log(cnf, mode, W_GROUP, "%s(%ld) removed", a_name->val, (long) gid);
134			return EXIT_SUCCESS;
135		} else if (mode == M_PRINT)
136			return print_group(grp, getarg(args, 'P') != NULL);
137
138		if (a_gid)
139			grp->gr_gid = (gid_t) atoi(a_gid->val);
140
141		if ((arg = getarg(args, 'l')) != NULL)
142			grp->gr_name = pw_checkname((u_char *)arg->val, 0);
143	} else {
144		if (a_name == NULL)	/* Required */
145			errx(EX_DATAERR, "group name required");
146		else if (grp != NULL)	/* Exists */
147			errx(EX_DATAERR, "group name `%s' already exists", a_name->val);
148
149		extendarray(&members, &grmembers, 200);
150		members[0] = NULL;
151		grp = &fakegroup;
152		grp->gr_name = pw_checkname((u_char *)a_name->val, 0);
153		grp->gr_passwd = "*";
154		grp->gr_gid = gr_gidpolicy(cnf, args);
155		grp->gr_mem = members;
156	}
157
158	/*
159	 * This allows us to set a group password Group passwords is an
160	 * antique idea, rarely used and insecure (no secure database) Should
161	 * be discouraged, but it is apparently still supported by some
162	 * software.
163	 */
164
165	if ((arg = getarg(args, 'h')) != NULL ||
166	    (arg = getarg(args, 'H')) != NULL) {
167		if (strcmp(arg->val, "-") == 0)
168			grp->gr_passwd = "*";	/* No access */
169		else {
170			int             fd = atoi(arg->val);
171			int		precrypt = (arg->ch == 'H');
172			int             b;
173			int             istty = isatty(fd);
174			struct termios  t;
175			char           *p, line[256];
176
177			if (istty) {
178				if (tcgetattr(fd, &t) == -1)
179					istty = 0;
180				else {
181					struct termios  n = t;
182
183					/* Disable echo */
184					n.c_lflag &= ~(ECHO);
185					tcsetattr(fd, TCSANOW, &n);
186					printf("%sassword for group %s:", (mode == M_UPDATE) ? "New p" : "P", grp->gr_name);
187					fflush(stdout);
188				}
189			}
190			b = read(fd, line, sizeof(line) - 1);
191			if (istty) {	/* Restore state */
192				tcsetattr(fd, TCSANOW, &t);
193				fputc('\n', stdout);
194				fflush(stdout);
195			}
196			if (b < 0) {
197				warn("-h file descriptor");
198				return EX_OSERR;
199			}
200			line[b] = '\0';
201			if ((p = strpbrk(line, " \t\r\n")) != NULL)
202				*p = '\0';
203			if (!*line)
204				errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
205			if (precrypt) {
206				if (strchr(line, ':') != NULL)
207					return EX_DATAERR;
208				grp->gr_passwd = line;
209			} else
210				grp->gr_passwd = pw_pwcrypt(line);
211		}
212	}
213
214	if (((arg = getarg(args, 'M')) != NULL ||
215	    (arg = getarg(args, 'd')) != NULL ||
216	    (arg = getarg(args, 'm')) != NULL) && arg->val) {
217		int	i = 0;
218		char   *p;
219		struct passwd	*pwd;
220
221		/* Make sure this is not stay NULL with -M "" */
222		extendarray(&members, &grmembers, 200);
223		if (arg->ch == 'd')
224			delete_members(&members, &grmembers, &i, arg, grp);
225		else if (arg->ch == 'm') {
226			int	k = 0;
227
228			while (grp->gr_mem[k] != NULL) {
229				if (extendarray(&members, &grmembers, i + 2) != -1)
230					members[i++] = grp->gr_mem[k];
231				k++;
232			}
233		}
234
235		if (arg->ch != 'd')
236			for (p = strtok(arg->val, ", \t"); p != NULL; p = strtok(NULL, ", \t")) {
237				int	j;
238
239				/*
240				 * Check for duplicates
241				 */
242				pwd = lookup_pwent(p);
243				for (j = 0; j < i && strcmp(members[j], pwd->pw_name) != 0; j++)
244					;
245				if (j == i && extendarray(&members, &grmembers, i + 2) != -1)
246					members[i++] = newstr(pwd->pw_name);
247			}
248		while (i < grmembers)
249			members[i++] = NULL;
250		grp->gr_mem = members;
251	}
252
253	if (getarg(args, 'N') != NULL)
254		return print_group(grp, getarg(args, 'P') != NULL);
255
256	if (mode == M_ADD && (rc = addgrent(grp)) != 0) {
257		if (rc == -1)
258			warnx("group '%s' already exists", grp->gr_name);
259		else
260			warn("group update");
261		return EX_IOERR;
262	} else if (mode == M_UPDATE && (rc = chggrent(a_name->val, grp)) != 0) {
263		if (rc == -1)
264			warnx("group '%s' not available (NIS?)", grp->gr_name);
265		else
266			warn("group update");
267		return EX_IOERR;
268	}
269	/* grp may have been invalidated */
270	if ((grp = GETGRNAM(a_name->val)) == NULL)
271		errx(EX_SOFTWARE, "group disappeared during update");
272
273	pw_log(cnf, mode, W_GROUP, "%s(%ld)", grp->gr_name, (long) grp->gr_gid);
274
275	if (members)
276		free(members);
277
278	return EXIT_SUCCESS;
279}
280
281
282/*
283 * Lookup a passwd entry using a name or UID.
284 */
285static struct passwd *
286lookup_pwent(const char *user)
287{
288	struct passwd *pwd;
289
290	if ((pwd = GETPWNAM(user)) == NULL &&
291	    (!isdigit((unsigned char)*user) ||
292	    (pwd = getpwuid((uid_t) atoi(user))) == NULL))
293		errx(EX_NOUSER, "user `%s' does not exist", user);
294
295	return (pwd);
296}
297
298
299/*
300 * Delete requested members from a group.
301 */
302static void
303delete_members(char ***members, int *grmembers, int *i, struct carg *arg,
304    struct group *grp)
305{
306	bool matchFound;
307	char *user;
308	char *valueCopy;
309	char *valuePtr;
310	int k;
311	struct passwd *pwd;
312
313	k = 0;
314	while (grp->gr_mem[k] != NULL) {
315		matchFound = false;
316		if ((valueCopy = strdup(arg->val)) == NULL)
317			errx(EX_UNAVAILABLE, "out of memory");
318		valuePtr = valueCopy;
319		while ((user = strsep(&valuePtr, ", \t")) != NULL) {
320			pwd = lookup_pwent(user);
321			if (strcmp(grp->gr_mem[k], pwd->pw_name) == 0) {
322				matchFound = true;
323				break;
324			}
325		}
326		free(valueCopy);
327
328		if (!matchFound &&
329		    extendarray(members, grmembers, *i + 2) != -1)
330			(*members)[(*i)++] = grp->gr_mem[k];
331
332		k++;
333	}
334
335	return;
336}
337
338
339static          gid_t
340gr_gidpolicy(struct userconf * cnf, struct cargs * args)
341{
342	struct group   *grp;
343	gid_t           gid = (gid_t) - 1;
344	struct carg    *a_gid = getarg(args, 'g');
345
346	/*
347	 * Check the given gid, if any
348	 */
349	if (a_gid != NULL) {
350		gid = (gid_t) atol(a_gid->val);
351
352		if ((grp = GETGRGID(gid)) != NULL && getarg(args, 'o') == NULL)
353			errx(EX_DATAERR, "gid `%ld' has already been allocated", (long) grp->gr_gid);
354	} else {
355		struct bitmap   bm;
356
357		/*
358		 * We need to allocate the next available gid under one of
359		 * two policies a) Grab the first unused gid b) Grab the
360		 * highest possible unused gid
361		 */
362		if (cnf->min_gid >= cnf->max_gid) {	/* Sanity claus^H^H^H^Hheck */
363			cnf->min_gid = 1000;
364			cnf->max_gid = 32000;
365		}
366		bm = bm_alloc(cnf->max_gid - cnf->min_gid + 1);
367
368		/*
369		 * Now, let's fill the bitmap from the password file
370		 */
371		SETGRENT();
372		while ((grp = GETGRENT()) != NULL)
373			if ((gid_t)grp->gr_gid >= (gid_t)cnf->min_gid &&
374                            (gid_t)grp->gr_gid <= (gid_t)cnf->max_gid)
375				bm_setbit(&bm, grp->gr_gid - cnf->min_gid);
376		ENDGRENT();
377
378		/*
379		 * Then apply the policy, with fallback to reuse if necessary
380		 */
381		if (cnf->reuse_gids)
382			gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
383		else {
384			gid = (gid_t) (bm_lastset(&bm) + 1);
385			if (!bm_isset(&bm, gid))
386				gid += cnf->min_gid;
387			else
388				gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
389		}
390
391		/*
392		 * Another sanity check
393		 */
394		if (gid < cnf->min_gid || gid > cnf->max_gid)
395			errx(EX_SOFTWARE, "unable to allocate a new gid - range fully used");
396		bm_dealloc(&bm);
397	}
398	return gid;
399}
400
401
402static int
403print_group(struct group * grp, int pretty)
404{
405	if (!pretty) {
406		int		buflen = 0;
407		char           *buf = NULL;
408
409		fmtgrent(&buf, &buflen, grp);
410		fputs(buf, stdout);
411		free(buf);
412	} else {
413		int             i;
414
415		printf("Group Name: %-15s   #%lu\n"
416		       "   Members: ",
417		       grp->gr_name, (long) grp->gr_gid);
418		for (i = 0; grp->gr_mem[i]; i++)
419			printf("%s%s", i ? "," : "", grp->gr_mem[i]);
420		fputs("\n\n", stdout);
421	}
422	return EXIT_SUCCESS;
423}
424