pw_group.c revision 284128 
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 284128 2015-06-07 19:03:41Z bapt $";
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#include <grp.h>
38#include <libutil.h>
39
40#include "pw.h"
41#include "bitmap.h"
42
43
44static struct passwd *lookup_pwent(const char *user);
45static void	delete_members(char ***members, int *grmembers, int *i,
46    struct carg *arg, struct group *grp);
47static int	print_group(struct group * grp);
48static gid_t    gr_gidpolicy(struct userconf * cnf, struct cargs * args);
49
50int
51pw_group(int mode, char *name, long id, struct cargs * args)
52{
53	int		rc;
54	struct carg    *a_newname = getarg(args, 'l');
55	struct carg    *arg;
56	struct group   *grp = NULL;
57	int	        grmembers = 0;
58	char           **members = NULL;
59	struct userconf	*cnf = conf.userconf;
60
61	static struct group fakegroup =
62	{
63		"nogroup",
64		"*",
65		-1,
66		NULL
67	};
68
69	if (mode == M_LOCK || mode == M_UNLOCK)
70		errx(EX_USAGE, "'lock' command is not available for groups");
71
72	/*
73	 * With M_NEXT, we only need to return the
74	 * next gid to stdout
75	 */
76	if (mode == M_NEXT) {
77		gid_t next = gr_gidpolicy(cnf, args);
78		if (getarg(args, 'q'))
79			return next;
80		printf("%u\n", next);
81		return EXIT_SUCCESS;
82	}
83
84	if (mode == M_PRINT && getarg(args, 'a')) {
85		SETGRENT();
86		while ((grp = GETGRENT()) != NULL)
87			print_group(grp);
88		ENDGRENT();
89		return EXIT_SUCCESS;
90	}
91	if (id < 0 && name == NULL)
92		errx(EX_DATAERR, "group name or id required");
93
94	grp = (name != NULL) ? GETGRNAM(name) : GETGRGID(id);
95
96	if (mode == M_UPDATE || mode == M_DELETE || mode == M_PRINT) {
97		if (name == NULL && grp == NULL)	/* Try harder */
98			grp = GETGRGID(id);
99
100		if (grp == NULL) {
101			if (mode == M_PRINT && getarg(args, 'F')) {
102				char	*fmems[1];
103				fmems[0] = NULL;
104				fakegroup.gr_name = name ? name : "nogroup";
105				fakegroup.gr_gid = (gid_t) id;
106				fakegroup.gr_mem = fmems;
107				return print_group(&fakegroup);
108			}
109			if (name == NULL)
110				errx(EX_DATAERR, "unknown group `%s'", name);
111			else
112				errx(EX_DATAERR, "unknown group `%ld'", id);
113		}
114		if (name == NULL)	/* Needed later */
115			name = grp->gr_name;
116
117		/*
118		 * Handle deletions now
119		 */
120		if (mode == M_DELETE) {
121			rc = delgrent(grp);
122			if (rc == -1)
123				err(EX_IOERR, "group '%s' not available (NIS?)",
124				    name);
125			else if (rc != 0) {
126				err(EX_IOERR, "group update");
127			}
128			pw_log(cnf, mode, W_GROUP, "%s(%ld) removed", name, id);
129			return EXIT_SUCCESS;
130		} else if (mode == M_PRINT)
131			return print_group(grp);
132
133		if (id > 0)
134			grp->gr_gid = (gid_t) id;
135
136		if (a_newname != NULL)
137			grp->gr_name = pw_checkname(a_newname->val, 0);
138	} else {
139		if (name == NULL)	/* Required */
140			errx(EX_DATAERR, "group name required");
141		else if (grp != NULL)	/* Exists */
142			errx(EX_DATAERR, "group name `%s' already exists", name);
143
144		extendarray(&members, &grmembers, 200);
145		members[0] = NULL;
146		grp = &fakegroup;
147		grp->gr_name = pw_checkname(name, 0);
148		grp->gr_passwd = "*";
149		grp->gr_gid = gr_gidpolicy(cnf, args);
150		grp->gr_mem = members;
151	}
152
153	/*
154	 * This allows us to set a group password Group passwords is an
155	 * antique idea, rarely used and insecure (no secure database) Should
156	 * be discouraged, but it is apparently still supported by some
157	 * software.
158	 */
159
160	if ((arg = getarg(args, 'h')) != NULL ||
161	    (arg = getarg(args, 'H')) != NULL) {
162		if (strcmp(arg->val, "-") == 0)
163			grp->gr_passwd = "*";	/* No access */
164		else {
165			int             fd = atoi(arg->val);
166			int		precrypt = (arg->ch == 'H');
167			int             b;
168			int             istty = isatty(fd);
169			struct termios  t;
170			char           *p, line[256];
171
172			if (istty) {
173				if (tcgetattr(fd, &t) == -1)
174					istty = 0;
175				else {
176					struct termios  n = t;
177
178					/* Disable echo */
179					n.c_lflag &= ~(ECHO);
180					tcsetattr(fd, TCSANOW, &n);
181					printf("%sassword for group %s:", (mode == M_UPDATE) ? "New p" : "P", grp->gr_name);
182					fflush(stdout);
183				}
184			}
185			b = read(fd, line, sizeof(line) - 1);
186			if (istty) {	/* Restore state */
187				tcsetattr(fd, TCSANOW, &t);
188				fputc('\n', stdout);
189				fflush(stdout);
190			}
191			if (b < 0)
192				err(EX_OSERR, "-h file descriptor");
193			line[b] = '\0';
194			if ((p = strpbrk(line, " \t\r\n")) != NULL)
195				*p = '\0';
196			if (!*line)
197				errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
198			if (precrypt) {
199				if (strchr(line, ':') != NULL)
200					return EX_DATAERR;
201				grp->gr_passwd = line;
202			} else
203				grp->gr_passwd = pw_pwcrypt(line);
204		}
205	}
206
207	if (((arg = getarg(args, 'M')) != NULL ||
208	    (arg = getarg(args, 'd')) != NULL ||
209	    (arg = getarg(args, 'm')) != NULL) && arg->val) {
210		int	i = 0;
211		char   *p;
212		struct passwd	*pwd;
213
214		/* Make sure this is not stay NULL with -M "" */
215		extendarray(&members, &grmembers, 200);
216		if (arg->ch == 'd')
217			delete_members(&members, &grmembers, &i, arg, grp);
218		else if (arg->ch == 'm') {
219			int	k = 0;
220
221			if (grp->gr_mem != NULL) {
222				while (grp->gr_mem[k] != NULL) {
223					if (extendarray(&members, &grmembers, i + 2) != -1)
224						members[i++] = grp->gr_mem[k];
225					k++;
226				}
227			}
228		}
229
230		if (arg->ch != 'd')
231			for (p = strtok(arg->val, ", \t"); p != NULL; p = strtok(NULL, ", \t")) {
232				int	j;
233
234				/*
235				 * Check for duplicates
236				 */
237				pwd = lookup_pwent(p);
238				for (j = 0; j < i && strcmp(members[j], pwd->pw_name) != 0; j++)
239					;
240				if (j == i && extendarray(&members, &grmembers, i + 2) != -1)
241					members[i++] = newstr(pwd->pw_name);
242			}
243		while (i < grmembers)
244			members[i++] = NULL;
245		grp->gr_mem = members;
246	}
247
248	if (conf.dryrun)
249		return print_group(grp);
250
251	if (mode == M_ADD && (rc = addgrent(grp)) != 0) {
252		if (rc == -1)
253			errx(EX_IOERR, "group '%s' already exists",
254			    grp->gr_name);
255		else
256			err(EX_IOERR, "group update");
257	} else if (mode == M_UPDATE && (rc = chggrent(name, grp)) != 0) {
258		if (rc == -1)
259			errx(EX_IOERR, "group '%s' not available (NIS?)",
260			    grp->gr_name);
261		else
262			err(EX_IOERR, "group update");
263	}
264
265	if (a_newname != NULL)
266		name = a_newname->val;
267	/* grp may have been invalidated */
268	if ((grp = GETGRNAM(name)) == NULL)
269		errx(EX_SOFTWARE, "group disappeared during update");
270
271	pw_log(cnf, mode, W_GROUP, "%s(%u)", grp->gr_name, grp->gr_gid);
272
273	free(members);
274
275	return EXIT_SUCCESS;
276}
277
278
279/*
280 * Lookup a passwd entry using a name or UID.
281 */
282static struct passwd *
283lookup_pwent(const char *user)
284{
285	struct passwd *pwd;
286
287	if ((pwd = GETPWNAM(user)) == NULL &&
288	    (!isdigit((unsigned char)*user) ||
289	    (pwd = getpwuid((uid_t) atoi(user))) == NULL))
290		errx(EX_NOUSER, "user `%s' does not exist", user);
291
292	return (pwd);
293}
294
295
296/*
297 * Delete requested members from a group.
298 */
299static void
300delete_members(char ***members, int *grmembers, int *i, struct carg *arg,
301    struct group *grp)
302{
303	bool matchFound;
304	char *user;
305	char *valueCopy;
306	char *valuePtr;
307	int k;
308	struct passwd *pwd;
309
310	if (grp->gr_mem == NULL)
311		return;
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 `%u' has already been allocated", 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)
404{
405	if (!conf.pretty) {
406		char           *buf = NULL;
407
408		buf = gr_make(grp);
409		printf("%s\n", buf);
410		free(buf);
411	} else {
412		int             i;
413
414		printf("Group Name: %-15s   #%lu\n"
415		       "   Members: ",
416		       grp->gr_name, (long) grp->gr_gid);
417		if (grp->gr_mem != NULL) {
418			for (i = 0; grp->gr_mem[i]; i++)
419				printf("%s%s", i ? "," : "", grp->gr_mem[i]);
420		}
421		fputs("\n\n", stdout);
422	}
423	return EXIT_SUCCESS;
424}
425