pw_group.c revision 277764 
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 277764 2015-01-26 16:50:42Z 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		if (strspn(a_gid->val, "0123456789") != strlen(a_gid->val))
72			errx(EX_USAGE, "-g expects a number");
73	}
74
75	if (mode == M_LOCK || mode == M_UNLOCK)
76		errx(EX_USAGE, "'lock' command is not available for groups");
77
78	/*
79	 * With M_NEXT, we only need to return the
80	 * next gid to stdout
81	 */
82	if (mode == M_NEXT) {
83		gid_t next = gr_gidpolicy(cnf, args);
84		if (getarg(args, 'q'))
85			return next;
86		printf("%ld\n", (long)next);
87		return EXIT_SUCCESS;
88	}
89
90	if (mode == M_PRINT && getarg(args, 'a')) {
91		int             pretty = getarg(args, 'P') != NULL;
92
93		SETGRENT();
94		while ((grp = GETGRENT()) != NULL)
95			print_group(grp, pretty);
96		ENDGRENT();
97		return EXIT_SUCCESS;
98	}
99	if (a_gid == NULL) {
100		if (a_name == NULL)
101			errx(EX_DATAERR, "group name or id required");
102
103		if (mode != M_ADD && grp == NULL && isdigit((unsigned char)*a_name->val)) {
104			(a_gid = a_name)->ch = 'g';
105			a_name = NULL;
106		}
107	}
108	grp = (a_name != NULL) ? GETGRNAM(a_name->val) : GETGRGID((gid_t) atoi(a_gid->val));
109
110	if (mode == M_UPDATE || mode == M_DELETE || mode == M_PRINT) {
111		if (a_name == NULL && grp == NULL)	/* Try harder */
112			grp = GETGRGID(atoi(a_gid->val));
113
114		if (grp == NULL) {
115			if (mode == M_PRINT && getarg(args, 'F')) {
116				char	*fmems[1];
117				fmems[0] = NULL;
118				fakegroup.gr_name = a_name ? a_name->val : "nogroup";
119				fakegroup.gr_gid = a_gid ? (gid_t) atol(a_gid->val) : -1;
120				fakegroup.gr_mem = fmems;
121				return print_group(&fakegroup, getarg(args, 'P') != NULL);
122			}
123			errx(EX_DATAERR, "unknown group `%s'", a_name ? a_name->val : a_gid->val);
124		}
125		if (a_name == NULL)	/* Needed later */
126			a_name = addarg(args, 'n', grp->gr_name);
127
128		/*
129		 * Handle deletions now
130		 */
131		if (mode == M_DELETE) {
132			gid_t           gid = grp->gr_gid;
133
134			rc = delgrent(grp);
135			if (rc == -1)
136				err(EX_IOERR, "group '%s' not available (NIS?)", grp->gr_name);
137			else if (rc != 0) {
138				warn("group update");
139				return EX_IOERR;
140			}
141			pw_log(cnf, mode, W_GROUP, "%s(%ld) removed", a_name->val, (long) gid);
142			return EXIT_SUCCESS;
143		} else if (mode == M_PRINT)
144			return print_group(grp, getarg(args, 'P') != NULL);
145
146		if (a_gid)
147			grp->gr_gid = (gid_t) atoi(a_gid->val);
148
149		if (a_newname != NULL)
150			grp->gr_name = pw_checkname((u_char *)a_newname->val, 0);
151	} else {
152		if (a_name == NULL)	/* Required */
153			errx(EX_DATAERR, "group name required");
154		else if (grp != NULL)	/* Exists */
155			errx(EX_DATAERR, "group name `%s' already exists", a_name->val);
156
157		extendarray(&members, &grmembers, 200);
158		members[0] = NULL;
159		grp = &fakegroup;
160		grp->gr_name = pw_checkname((u_char *)a_name->val, 0);
161		grp->gr_passwd = "*";
162		grp->gr_gid = gr_gidpolicy(cnf, args);
163		grp->gr_mem = members;
164	}
165
166	/*
167	 * This allows us to set a group password Group passwords is an
168	 * antique idea, rarely used and insecure (no secure database) Should
169	 * be discouraged, but it is apparently still supported by some
170	 * software.
171	 */
172
173	if ((arg = getarg(args, 'h')) != NULL ||
174	    (arg = getarg(args, 'H')) != NULL) {
175		if (strcmp(arg->val, "-") == 0)
176			grp->gr_passwd = "*";	/* No access */
177		else {
178			int             fd = atoi(arg->val);
179			int		precrypt = (arg->ch == 'H');
180			int             b;
181			int             istty = isatty(fd);
182			struct termios  t;
183			char           *p, line[256];
184
185			if (istty) {
186				if (tcgetattr(fd, &t) == -1)
187					istty = 0;
188				else {
189					struct termios  n = t;
190
191					/* Disable echo */
192					n.c_lflag &= ~(ECHO);
193					tcsetattr(fd, TCSANOW, &n);
194					printf("%sassword for group %s:", (mode == M_UPDATE) ? "New p" : "P", grp->gr_name);
195					fflush(stdout);
196				}
197			}
198			b = read(fd, line, sizeof(line) - 1);
199			if (istty) {	/* Restore state */
200				tcsetattr(fd, TCSANOW, &t);
201				fputc('\n', stdout);
202				fflush(stdout);
203			}
204			if (b < 0) {
205				warn("-h file descriptor");
206				return EX_OSERR;
207			}
208			line[b] = '\0';
209			if ((p = strpbrk(line, " \t\r\n")) != NULL)
210				*p = '\0';
211			if (!*line)
212				errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
213			if (precrypt) {
214				if (strchr(line, ':') != NULL)
215					return EX_DATAERR;
216				grp->gr_passwd = line;
217			} else
218				grp->gr_passwd = pw_pwcrypt(line);
219		}
220	}
221
222	if (((arg = getarg(args, 'M')) != NULL ||
223	    (arg = getarg(args, 'd')) != NULL ||
224	    (arg = getarg(args, 'm')) != NULL) && arg->val) {
225		int	i = 0;
226		char   *p;
227		struct passwd	*pwd;
228
229		/* Make sure this is not stay NULL with -M "" */
230		extendarray(&members, &grmembers, 200);
231		if (arg->ch == 'd')
232			delete_members(&members, &grmembers, &i, arg, grp);
233		else if (arg->ch == 'm') {
234			int	k = 0;
235
236			if (grp->gr_mem != NULL) {
237				while (grp->gr_mem[k] != NULL) {
238					if (extendarray(&members, &grmembers, i + 2) != -1)
239						members[i++] = grp->gr_mem[k];
240					k++;
241				}
242			}
243		}
244
245		if (arg->ch != 'd')
246			for (p = strtok(arg->val, ", \t"); p != NULL; p = strtok(NULL, ", \t")) {
247				int	j;
248
249				/*
250				 * Check for duplicates
251				 */
252				pwd = lookup_pwent(p);
253				for (j = 0; j < i && strcmp(members[j], pwd->pw_name) != 0; j++)
254					;
255				if (j == i && extendarray(&members, &grmembers, i + 2) != -1)
256					members[i++] = newstr(pwd->pw_name);
257			}
258		while (i < grmembers)
259			members[i++] = NULL;
260		grp->gr_mem = members;
261	}
262
263	if (getarg(args, 'N') != NULL)
264		return print_group(grp, getarg(args, 'P') != NULL);
265
266	if (mode == M_ADD && (rc = addgrent(grp)) != 0) {
267		if (rc == -1)
268			warnx("group '%s' already exists", grp->gr_name);
269		else
270			warn("group update");
271		return EX_IOERR;
272	} else if (mode == M_UPDATE && (rc = chggrent(a_name->val, grp)) != 0) {
273		if (rc == -1)
274			warnx("group '%s' not available (NIS?)", grp->gr_name);
275		else
276			warn("group update");
277		return EX_IOERR;
278	}
279
280	arg = a_newname != NULL ? a_newname : a_name;
281	/* grp may have been invalidated */
282	if ((grp = GETGRNAM(arg->val)) == NULL)
283		errx(EX_SOFTWARE, "group disappeared during update");
284
285	pw_log(cnf, mode, W_GROUP, "%s(%ld)", grp->gr_name, (long) grp->gr_gid);
286
287	free(members);
288
289	return EXIT_SUCCESS;
290}
291
292
293/*
294 * Lookup a passwd entry using a name or UID.
295 */
296static struct passwd *
297lookup_pwent(const char *user)
298{
299	struct passwd *pwd;
300
301	if ((pwd = GETPWNAM(user)) == NULL &&
302	    (!isdigit((unsigned char)*user) ||
303	    (pwd = getpwuid((uid_t) atoi(user))) == NULL))
304		errx(EX_NOUSER, "user `%s' does not exist", user);
305
306	return (pwd);
307}
308
309
310/*
311 * Delete requested members from a group.
312 */
313static void
314delete_members(char ***members, int *grmembers, int *i, struct carg *arg,
315    struct group *grp)
316{
317	bool matchFound;
318	char *user;
319	char *valueCopy;
320	char *valuePtr;
321	int k;
322	struct passwd *pwd;
323
324	if (grp->gr_mem == NULL)
325		return;
326
327	k = 0;
328	while (grp->gr_mem[k] != NULL) {
329		matchFound = false;
330		if ((valueCopy = strdup(arg->val)) == NULL)
331			errx(EX_UNAVAILABLE, "out of memory");
332		valuePtr = valueCopy;
333		while ((user = strsep(&valuePtr, ", \t")) != NULL) {
334			pwd = lookup_pwent(user);
335			if (strcmp(grp->gr_mem[k], pwd->pw_name) == 0) {
336				matchFound = true;
337				break;
338			}
339		}
340		free(valueCopy);
341
342		if (!matchFound &&
343		    extendarray(members, grmembers, *i + 2) != -1)
344			(*members)[(*i)++] = grp->gr_mem[k];
345
346		k++;
347	}
348
349	return;
350}
351
352
353static          gid_t
354gr_gidpolicy(struct userconf * cnf, struct cargs * args)
355{
356	struct group   *grp;
357	gid_t           gid = (gid_t) - 1;
358	struct carg    *a_gid = getarg(args, 'g');
359
360	/*
361	 * Check the given gid, if any
362	 */
363	if (a_gid != NULL) {
364		gid = (gid_t) atol(a_gid->val);
365
366		if ((grp = GETGRGID(gid)) != NULL && getarg(args, 'o') == NULL)
367			errx(EX_DATAERR, "gid `%ld' has already been allocated", (long) grp->gr_gid);
368	} else {
369		struct bitmap   bm;
370
371		/*
372		 * We need to allocate the next available gid under one of
373		 * two policies a) Grab the first unused gid b) Grab the
374		 * highest possible unused gid
375		 */
376		if (cnf->min_gid >= cnf->max_gid) {	/* Sanity claus^H^H^H^Hheck */
377			cnf->min_gid = 1000;
378			cnf->max_gid = 32000;
379		}
380		bm = bm_alloc(cnf->max_gid - cnf->min_gid + 1);
381
382		/*
383		 * Now, let's fill the bitmap from the password file
384		 */
385		SETGRENT();
386		while ((grp = GETGRENT()) != NULL)
387			if ((gid_t)grp->gr_gid >= (gid_t)cnf->min_gid &&
388                            (gid_t)grp->gr_gid <= (gid_t)cnf->max_gid)
389				bm_setbit(&bm, grp->gr_gid - cnf->min_gid);
390		ENDGRENT();
391
392		/*
393		 * Then apply the policy, with fallback to reuse if necessary
394		 */
395		if (cnf->reuse_gids)
396			gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
397		else {
398			gid = (gid_t) (bm_lastset(&bm) + 1);
399			if (!bm_isset(&bm, gid))
400				gid += cnf->min_gid;
401			else
402				gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
403		}
404
405		/*
406		 * Another sanity check
407		 */
408		if (gid < cnf->min_gid || gid > cnf->max_gid)
409			errx(EX_SOFTWARE, "unable to allocate a new gid - range fully used");
410		bm_dealloc(&bm);
411	}
412	return gid;
413}
414
415
416static int
417print_group(struct group * grp, int pretty)
418{
419	if (!pretty) {
420		char           *buf = NULL;
421
422		buf = gr_make(grp);
423		printf("%s\n", buf);
424		free(buf);
425	} else {
426		int             i;
427
428		printf("Group Name: %-15s   #%lu\n"
429		       "   Members: ",
430		       grp->gr_name, (long) grp->gr_gid);
431		if (grp->gr_mem != NULL) {
432			for (i = 0; grp->gr_mem[i]; i++)
433				printf("%s%s", i ? "," : "", grp->gr_mem[i]);
434		}
435		fputs("\n\n", stdout);
436	}
437	return EXIT_SUCCESS;
438}
439