pw_group.c revision 277652 
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 277652 2015-01-24 19:13:03Z 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, int pretty);
48static gid_t    gr_gidpolicy(struct userconf * cnf, struct cargs * args);
49
50int
51pw_group(struct userconf * cnf, int mode, struct cargs * args)
52{
53	int		rc;
54	struct carg    *a_newname = getarg(args, 'l');
55	struct carg    *a_name = getarg(args, 'n');
56	struct carg    *a_gid = getarg(args, 'g');
57	struct carg    *arg;
58	struct group   *grp = NULL;
59	int	        grmembers = 0;
60	char           **members = NULL;
61
62	static struct group fakegroup =
63	{
64		"nogroup",
65		"*",
66		-1,
67		NULL
68	};
69
70	if (a_gid != NULL) {
71		const char *teststr;
72		teststr = a_gid->val;
73		if (*teststr == '-')
74			teststr++;
75		if (strspn(teststr, "0123456789") != strlen(teststr))
76			errx(EX_USAGE, "-g expects a number");
77	}
78
79	if (mode == M_LOCK || mode == M_UNLOCK)
80		errx(EX_USAGE, "'lock' command is not available for groups");
81
82	/*
83	 * With M_NEXT, we only need to return the
84	 * next gid to stdout
85	 */
86	if (mode == M_NEXT) {
87		gid_t next = gr_gidpolicy(cnf, args);
88		if (getarg(args, 'q'))
89			return next;
90		printf("%ld\n", (long)next);
91		return EXIT_SUCCESS;
92	}
93
94	if (mode == M_PRINT && getarg(args, 'a')) {
95		int             pretty = getarg(args, 'P') != NULL;
96
97		SETGRENT();
98		while ((grp = GETGRENT()) != NULL)
99			print_group(grp, pretty);
100		ENDGRENT();
101		return EXIT_SUCCESS;
102	}
103	if (a_gid == NULL) {
104		if (a_name == NULL)
105			errx(EX_DATAERR, "group name or id required");
106
107		if (mode != M_ADD && grp == NULL && isdigit((unsigned char)*a_name->val)) {
108			(a_gid = a_name)->ch = 'g';
109			a_name = NULL;
110		}
111	}
112	grp = (a_name != NULL) ? GETGRNAM(a_name->val) : GETGRGID((gid_t) atoi(a_gid->val));
113
114	if (mode == M_UPDATE || mode == M_DELETE || mode == M_PRINT) {
115		if (a_name == NULL && grp == NULL)	/* Try harder */
116			grp = GETGRGID(atoi(a_gid->val));
117
118		if (grp == NULL) {
119			if (mode == M_PRINT && getarg(args, 'F')) {
120				char	*fmems[1];
121				fmems[0] = NULL;
122				fakegroup.gr_name = a_name ? a_name->val : "nogroup";
123				fakegroup.gr_gid = a_gid ? (gid_t) atol(a_gid->val) : -1;
124				fakegroup.gr_mem = fmems;
125				return print_group(&fakegroup, getarg(args, 'P') != NULL);
126			}
127			errx(EX_DATAERR, "unknown group `%s'", a_name ? a_name->val : a_gid->val);
128		}
129		if (a_name == NULL)	/* Needed later */
130			a_name = addarg(args, 'n', grp->gr_name);
131
132		/*
133		 * Handle deletions now
134		 */
135		if (mode == M_DELETE) {
136			gid_t           gid = grp->gr_gid;
137
138			rc = delgrent(grp);
139			if (rc == -1)
140				err(EX_IOERR, "group '%s' not available (NIS?)", grp->gr_name);
141			else if (rc != 0) {
142				warn("group update");
143				return EX_IOERR;
144			}
145			pw_log(cnf, mode, W_GROUP, "%s(%ld) removed", a_name->val, (long) gid);
146			return EXIT_SUCCESS;
147		} else if (mode == M_PRINT)
148			return print_group(grp, getarg(args, 'P') != NULL);
149
150		if (a_gid)
151			grp->gr_gid = (gid_t) atoi(a_gid->val);
152
153		if (a_newname != NULL)
154			grp->gr_name = pw_checkname((u_char *)a_newname->val, 0);
155	} else {
156		if (a_name == NULL)	/* Required */
157			errx(EX_DATAERR, "group name required");
158		else if (grp != NULL)	/* Exists */
159			errx(EX_DATAERR, "group name `%s' already exists", a_name->val);
160
161		extendarray(&members, &grmembers, 200);
162		members[0] = NULL;
163		grp = &fakegroup;
164		grp->gr_name = pw_checkname((u_char *)a_name->val, 0);
165		grp->gr_passwd = "*";
166		grp->gr_gid = gr_gidpolicy(cnf, args);
167		grp->gr_mem = members;
168	}
169
170	/*
171	 * This allows us to set a group password Group passwords is an
172	 * antique idea, rarely used and insecure (no secure database) Should
173	 * be discouraged, but it is apparently still supported by some
174	 * software.
175	 */
176
177	if ((arg = getarg(args, 'h')) != NULL ||
178	    (arg = getarg(args, 'H')) != NULL) {
179		if (strcmp(arg->val, "-") == 0)
180			grp->gr_passwd = "*";	/* No access */
181		else {
182			int             fd = atoi(arg->val);
183			int		precrypt = (arg->ch == 'H');
184			int             b;
185			int             istty = isatty(fd);
186			struct termios  t;
187			char           *p, line[256];
188
189			if (istty) {
190				if (tcgetattr(fd, &t) == -1)
191					istty = 0;
192				else {
193					struct termios  n = t;
194
195					/* Disable echo */
196					n.c_lflag &= ~(ECHO);
197					tcsetattr(fd, TCSANOW, &n);
198					printf("%sassword for group %s:", (mode == M_UPDATE) ? "New p" : "P", grp->gr_name);
199					fflush(stdout);
200				}
201			}
202			b = read(fd, line, sizeof(line) - 1);
203			if (istty) {	/* Restore state */
204				tcsetattr(fd, TCSANOW, &t);
205				fputc('\n', stdout);
206				fflush(stdout);
207			}
208			if (b < 0) {
209				warn("-h file descriptor");
210				return EX_OSERR;
211			}
212			line[b] = '\0';
213			if ((p = strpbrk(line, " \t\r\n")) != NULL)
214				*p = '\0';
215			if (!*line)
216				errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
217			if (precrypt) {
218				if (strchr(line, ':') != NULL)
219					return EX_DATAERR;
220				grp->gr_passwd = line;
221			} else
222				grp->gr_passwd = pw_pwcrypt(line);
223		}
224	}
225
226	if (((arg = getarg(args, 'M')) != NULL ||
227	    (arg = getarg(args, 'd')) != NULL ||
228	    (arg = getarg(args, 'm')) != NULL) && arg->val) {
229		int	i = 0;
230		char   *p;
231		struct passwd	*pwd;
232
233		/* Make sure this is not stay NULL with -M "" */
234		extendarray(&members, &grmembers, 200);
235		if (arg->ch == 'd')
236			delete_members(&members, &grmembers, &i, arg, grp);
237		else if (arg->ch == 'm') {
238			int	k = 0;
239
240			if (grp->gr_mem != NULL) {
241				while (grp->gr_mem[k] != NULL) {
242					if (extendarray(&members, &grmembers, i + 2) != -1)
243						members[i++] = grp->gr_mem[k];
244					k++;
245				}
246			}
247		}
248
249		if (arg->ch != 'd')
250			for (p = strtok(arg->val, ", \t"); p != NULL; p = strtok(NULL, ", \t")) {
251				int	j;
252
253				/*
254				 * Check for duplicates
255				 */
256				pwd = lookup_pwent(p);
257				for (j = 0; j < i && strcmp(members[j], pwd->pw_name) != 0; j++)
258					;
259				if (j == i && extendarray(&members, &grmembers, i + 2) != -1)
260					members[i++] = newstr(pwd->pw_name);
261			}
262		while (i < grmembers)
263			members[i++] = NULL;
264		grp->gr_mem = members;
265	}
266
267	if (getarg(args, 'N') != NULL)
268		return print_group(grp, getarg(args, 'P') != NULL);
269
270	if (mode == M_ADD && (rc = addgrent(grp)) != 0) {
271		if (rc == -1)
272			warnx("group '%s' already exists", grp->gr_name);
273		else
274			warn("group update");
275		return EX_IOERR;
276	} else if (mode == M_UPDATE && (rc = chggrent(a_name->val, grp)) != 0) {
277		if (rc == -1)
278			warnx("group '%s' not available (NIS?)", grp->gr_name);
279		else
280			warn("group update");
281		return EX_IOERR;
282	}
283
284	arg = a_newname != NULL ? a_newname : a_name;
285	/* grp may have been invalidated */
286	if ((grp = GETGRNAM(arg->val)) == NULL)
287		errx(EX_SOFTWARE, "group disappeared during update");
288
289	pw_log(cnf, mode, W_GROUP, "%s(%ld)", grp->gr_name, (long) grp->gr_gid);
290
291	free(members);
292
293	return EXIT_SUCCESS;
294}
295
296
297/*
298 * Lookup a passwd entry using a name or UID.
299 */
300static struct passwd *
301lookup_pwent(const char *user)
302{
303	struct passwd *pwd;
304
305	if ((pwd = GETPWNAM(user)) == NULL &&
306	    (!isdigit((unsigned char)*user) ||
307	    (pwd = getpwuid((uid_t) atoi(user))) == NULL))
308		errx(EX_NOUSER, "user `%s' does not exist", user);
309
310	return (pwd);
311}
312
313
314/*
315 * Delete requested members from a group.
316 */
317static void
318delete_members(char ***members, int *grmembers, int *i, struct carg *arg,
319    struct group *grp)
320{
321	bool matchFound;
322	char *user;
323	char *valueCopy;
324	char *valuePtr;
325	int k;
326	struct passwd *pwd;
327
328	if (grp->gr_mem == NULL)
329		return;
330
331	k = 0;
332	while (grp->gr_mem[k] != NULL) {
333		matchFound = false;
334		if ((valueCopy = strdup(arg->val)) == NULL)
335			errx(EX_UNAVAILABLE, "out of memory");
336		valuePtr = valueCopy;
337		while ((user = strsep(&valuePtr, ", \t")) != NULL) {
338			pwd = lookup_pwent(user);
339			if (strcmp(grp->gr_mem[k], pwd->pw_name) == 0) {
340				matchFound = true;
341				break;
342			}
343		}
344		free(valueCopy);
345
346		if (!matchFound &&
347		    extendarray(members, grmembers, *i + 2) != -1)
348			(*members)[(*i)++] = grp->gr_mem[k];
349
350		k++;
351	}
352
353	return;
354}
355
356
357static          gid_t
358gr_gidpolicy(struct userconf * cnf, struct cargs * args)
359{
360	struct group   *grp;
361	gid_t           gid = (gid_t) - 1;
362	struct carg    *a_gid = getarg(args, 'g');
363
364	/*
365	 * Check the given gid, if any
366	 */
367	if (a_gid != NULL) {
368		gid = (gid_t) atol(a_gid->val);
369
370		if ((grp = GETGRGID(gid)) != NULL && getarg(args, 'o') == NULL)
371			errx(EX_DATAERR, "gid `%ld' has already been allocated", (long) grp->gr_gid);
372	} else {
373		struct bitmap   bm;
374
375		/*
376		 * We need to allocate the next available gid under one of
377		 * two policies a) Grab the first unused gid b) Grab the
378		 * highest possible unused gid
379		 */
380		if (cnf->min_gid >= cnf->max_gid) {	/* Sanity claus^H^H^H^Hheck */
381			cnf->min_gid = 1000;
382			cnf->max_gid = 32000;
383		}
384		bm = bm_alloc(cnf->max_gid - cnf->min_gid + 1);
385
386		/*
387		 * Now, let's fill the bitmap from the password file
388		 */
389		SETGRENT();
390		while ((grp = GETGRENT()) != NULL)
391			if ((gid_t)grp->gr_gid >= (gid_t)cnf->min_gid &&
392                            (gid_t)grp->gr_gid <= (gid_t)cnf->max_gid)
393				bm_setbit(&bm, grp->gr_gid - cnf->min_gid);
394		ENDGRENT();
395
396		/*
397		 * Then apply the policy, with fallback to reuse if necessary
398		 */
399		if (cnf->reuse_gids)
400			gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
401		else {
402			gid = (gid_t) (bm_lastset(&bm) + 1);
403			if (!bm_isset(&bm, gid))
404				gid += cnf->min_gid;
405			else
406				gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
407		}
408
409		/*
410		 * Another sanity check
411		 */
412		if (gid < cnf->min_gid || gid > cnf->max_gid)
413			errx(EX_SOFTWARE, "unable to allocate a new gid - range fully used");
414		bm_dealloc(&bm);
415	}
416	return gid;
417}
418
419
420static int
421print_group(struct group * grp, int pretty)
422{
423	if (!pretty) {
424		char           *buf = NULL;
425
426		buf = gr_make(grp);
427		printf("%s\n", buf);
428		free(buf);
429	} else {
430		int             i;
431
432		printf("Group Name: %-15s   #%lu\n"
433		       "   Members: ",
434		       grp->gr_name, (long) grp->gr_gid);
435		if (grp->gr_mem != NULL) {
436			for (i = 0; grp->gr_mem[i]; i++)
437				printf("%s%s", i ? "," : "", grp->gr_mem[i]);
438		}
439		fputs("\n\n", stdout);
440	}
441	return EXIT_SUCCESS;
442}
443