xref: /freebsd/usr.sbin/pw/pw_group.c (revision 23f282aa31e9b6fceacd449020e936e98d6f2298)
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
28 static const char rcsid[] =
29   "$FreeBSD$";
30 #endif /* not lint */
31 
32 #include <ctype.h>
33 #include <err.h>
34 #include <termios.h>
35 #include <unistd.h>
36 
37 #include "pw.h"
38 #include "bitmap.h"
39 
40 
41 static int      print_group(struct group * grp, int pretty);
42 static gid_t    gr_gidpolicy(struct userconf * cnf, struct cargs * args);
43 
44 int
45 pw_group(struct userconf * cnf, int mode, struct cargs * args)
46 {
47 	int		rc;
48 	struct carg    *a_name = getarg(args, 'n');
49 	struct carg    *a_gid = getarg(args, 'g');
50 	struct carg    *arg;
51 	struct group   *grp = NULL;
52 	int	        grmembers = 0;
53 	char           **members = NULL;
54 
55 	static struct group fakegroup =
56 	{
57 		"nogroup",
58 		"*",
59 		-1,
60 		NULL
61 	};
62 
63 	if (mode == M_LOCK || mode == M_UNLOCK)
64 		errx(EX_USAGE, "'lock' command is not available for groups");
65 
66 	/*
67 	 * With M_NEXT, we only need to return the
68 	 * next gid to stdout
69 	 */
70 	if (mode == M_NEXT) {
71 		gid_t next = gr_gidpolicy(cnf, args);
72 		if (getarg(args, 'q'))
73 			return next;
74 		printf("%ld\n", (long)next);
75 		return EXIT_SUCCESS;
76 	}
77 
78 	if (mode == M_PRINT && getarg(args, 'a')) {
79 		int             pretty = getarg(args, 'P') != NULL;
80 
81 		SETGRENT();
82 		while ((grp = GETGRENT()) != NULL)
83 			print_group(grp, pretty);
84 		ENDGRENT();
85 		return EXIT_SUCCESS;
86 	}
87 	if (a_gid == NULL) {
88 		if (a_name == NULL)
89 			errx(EX_DATAERR, "group name or id required");
90 
91 		if (mode != M_ADD && grp == NULL && isdigit(*a_name->val)) {
92 			(a_gid = a_name)->ch = 'g';
93 			a_name = NULL;
94 		}
95 	}
96 	grp = (a_name != NULL) ? GETGRNAM(a_name->val) : GETGRGID((gid_t) atoi(a_gid->val));
97 
98 	if (mode == M_UPDATE || mode == M_DELETE || mode == M_PRINT) {
99 		if (a_name == NULL && grp == NULL)	/* Try harder */
100 			grp = GETGRGID(atoi(a_gid->val));
101 
102 		if (grp == NULL) {
103 			if (mode == M_PRINT && getarg(args, 'F')) {
104 				char	*fmems[1];
105 				fmems[0] = NULL;
106 				fakegroup.gr_name = a_name ? a_name->val : "nogroup";
107 				fakegroup.gr_gid = a_gid ? (gid_t) atol(a_gid->val) : -1;
108 				fakegroup.gr_mem = fmems;
109 				return print_group(&fakegroup, getarg(args, 'P') != NULL);
110 			}
111 			errx(EX_DATAERR, "unknown group `%s'", a_name ? a_name->val : a_gid->val);
112 		}
113 		if (a_name == NULL)	/* Needed later */
114 			a_name = addarg(args, 'n', grp->gr_name);
115 
116 		/*
117 		 * Handle deletions now
118 		 */
119 		if (mode == M_DELETE) {
120 			gid_t           gid = grp->gr_gid;
121 
122 			rc = delgrent(grp);
123 			if (rc == -1)
124 				err(EX_IOERR, "group '%s' not available (NIS?)", grp->gr_name);
125 			else if (rc != 0) {
126 				warn("group update");
127 				return EX_IOERR;
128 			}
129 			pw_log(cnf, mode, W_GROUP, "%s(%ld) removed", a_name->val, (long) gid);
130 			return EXIT_SUCCESS;
131 		} else if (mode == M_PRINT)
132 			return print_group(grp, getarg(args, 'P') != NULL);
133 
134 		if (a_gid)
135 			grp->gr_gid = (gid_t) atoi(a_gid->val);
136 
137 		if ((arg = getarg(args, 'l')) != NULL)
138 			grp->gr_name = pw_checkname((u_char *)arg->val, 0);
139 	} else {
140 		if (a_name == NULL)	/* Required */
141 			errx(EX_DATAERR, "group name required");
142 		else if (grp != NULL)	/* Exists */
143 			errx(EX_DATAERR, "group name `%s' already exists", a_name->val);
144 
145 		extendarray(&members, &grmembers, 200);
146 		members[0] = NULL;
147 		grp = &fakegroup;
148 		grp->gr_name = pw_checkname((u_char *)a_name->val, 0);
149 		grp->gr_passwd = "*";
150 		grp->gr_gid = gr_gidpolicy(cnf, args);
151 		grp->gr_mem = members;
152 	}
153 
154 	/*
155 	 * This allows us to set a group password Group passwords is an
156 	 * antique idea, rarely used and insecure (no secure database) Should
157 	 * be discouraged, but it is apparently still supported by some
158 	 * software.
159 	 */
160 
161 	if ((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             b;
167 			int             istty = isatty(fd);
168 			struct termios  t;
169 			char           *p, line[256];
170 
171 			if (istty) {
172 				if (tcgetattr(fd, &t) == -1)
173 					istty = 0;
174 				else {
175 					struct termios  n = t;
176 
177 					/* Disable echo */
178 					n.c_lflag &= ~(ECHO);
179 					tcsetattr(fd, TCSANOW, &n);
180 					printf("%sassword for group %s:", (mode == M_UPDATE) ? "New p" : "P", grp->gr_name);
181 					fflush(stdout);
182 				}
183 			}
184 			b = read(fd, line, sizeof(line) - 1);
185 			if (istty) {	/* Restore state */
186 				tcsetattr(fd, TCSANOW, &t);
187 				fputc('\n', stdout);
188 				fflush(stdout);
189 			}
190 			if (b < 0) {
191 				warn("-h file descriptor");
192 				return EX_OSERR;
193 			}
194 			line[b] = '\0';
195 			if ((p = strpbrk(line, " \t\r\n")) != NULL)
196 				*p = '\0';
197 			if (!*line)
198 				errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
199 			grp->gr_passwd = pw_pwcrypt(line);
200 		}
201 	}
202 
203 	if (((arg = getarg(args, 'M')) != NULL || (arg = getarg(args, 'm')) != NULL) && arg->val) {
204 		int	i = 0;
205 		char   *p;
206 		struct passwd	*pwd;
207 
208 		/* Make sure this is not stay NULL with -M "" */
209 		extendarray(&members, &grmembers, 200);
210 		if (arg->ch == 'm') {
211 			int	k = 0;
212 
213 			while (grp->gr_mem[k] != NULL) {
214 				if (extendarray(&members, &grmembers, i + 2) != -1) {
215 					members[i++] = grp->gr_mem[k];
216 				}
217 				k++;
218 			}
219 		}
220 		for (p = strtok(arg->val, ", \t"); p != NULL; p = strtok(NULL, ", \t")) {
221 			int     j;
222 			if ((pwd = GETPWNAM(p)) == NULL) {
223 				if (!isdigit(*p) || (pwd = getpwuid((uid_t) atoi(p))) == NULL)
224 					errx(EX_NOUSER, "user `%s' does not exist", p);
225 			}
226 			/*
227 			 * Check for duplicates
228 			 */
229 			for (j = 0; j < i && strcmp(members[j], pwd->pw_name)!=0; j++)
230 				;
231 			if (j == i && extendarray(&members, &grmembers, i + 2) != -1)
232 				members[i++] = newstr(pwd->pw_name);
233 		}
234 		while (i < grmembers)
235 			members[i++] = NULL;
236 		grp->gr_mem = members;
237 	}
238 
239 	if (getarg(args, 'N') != NULL)
240 		return print_group(grp, getarg(args, 'P') != NULL);
241 
242 	if (mode == M_ADD && (rc = addgrent(grp)) != 0) {
243 		if (rc == -1)
244 			warnx("group '%s' already exists", grp->gr_name);
245 		else
246 			warn("group update");
247 		return EX_IOERR;
248 	} else if (mode == M_UPDATE && (rc = chggrent(a_name->val, grp)) != 0) {
249 		if (rc == -1)
250 			warnx("group '%s' not available (NIS?)", grp->gr_name);
251 		else
252 			warn("group update");
253 		return EX_IOERR;
254 	}
255 	/* grp may have been invalidated */
256 	if ((grp = GETGRNAM(a_name->val)) == NULL)
257 		errx(EX_SOFTWARE, "group disappeared during update");
258 
259 	pw_log(cnf, mode, W_GROUP, "%s(%ld)", grp->gr_name, (long) grp->gr_gid);
260 
261 	if (members)
262 		free(members);
263 
264 	return EXIT_SUCCESS;
265 }
266 
267 
268 static          gid_t
269 gr_gidpolicy(struct userconf * cnf, struct cargs * args)
270 {
271 	struct group   *grp;
272 	gid_t           gid = (gid_t) - 1;
273 	struct carg    *a_gid = getarg(args, 'g');
274 
275 	/*
276 	 * Check the given gid, if any
277 	 */
278 	if (a_gid != NULL) {
279 		gid = (gid_t) atol(a_gid->val);
280 
281 		if ((grp = GETGRGID(gid)) != NULL && getarg(args, 'o') == NULL)
282 			errx(EX_DATAERR, "gid `%ld' has already been allocated", (long) grp->gr_gid);
283 	} else {
284 		struct bitmap   bm;
285 
286 		/*
287 		 * We need to allocate the next available gid under one of
288 		 * two policies a) Grab the first unused gid b) Grab the
289 		 * highest possible unused gid
290 		 */
291 		if (cnf->min_gid >= cnf->max_gid) {	/* Sanity claus^H^H^H^Hheck */
292 			cnf->min_gid = 1000;
293 			cnf->max_gid = 32000;
294 		}
295 		bm = bm_alloc(cnf->max_gid - cnf->min_gid + 1);
296 
297 		/*
298 		 * Now, let's fill the bitmap from the password file
299 		 */
300 		SETGRENT();
301 		while ((grp = GETGRENT()) != NULL)
302 			if ((gid_t)grp->gr_gid >= (gid_t)cnf->min_gid &&
303                             (gid_t)grp->gr_gid <= (gid_t)cnf->max_gid)
304 				bm_setbit(&bm, grp->gr_gid - cnf->min_gid);
305 		ENDGRENT();
306 
307 		/*
308 		 * Then apply the policy, with fallback to reuse if necessary
309 		 */
310 		if (cnf->reuse_gids)
311 			gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
312 		else {
313 			gid = (gid_t) (bm_lastset(&bm) + 1);
314 			if (!bm_isset(&bm, gid))
315 				gid += cnf->min_gid;
316 			else
317 				gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
318 		}
319 
320 		/*
321 		 * Another sanity check
322 		 */
323 		if (gid < cnf->min_gid || gid > cnf->max_gid)
324 			errx(EX_SOFTWARE, "unable to allocate a new gid - range fully used");
325 		bm_dealloc(&bm);
326 	}
327 	return gid;
328 }
329 
330 
331 static int
332 print_group(struct group * grp, int pretty)
333 {
334 	if (!pretty) {
335 		int		buflen = 0;
336 		char           *buf = NULL;
337 
338 		fmtgrent(&buf, &buflen, grp);
339 		fputs(buf, stdout);
340 		free(buf);
341 	} else {
342 		int             i;
343 
344 		printf("Group Name: %-15s   #%lu\n"
345 		       "   Members: ",
346 		       grp->gr_name, (long) grp->gr_gid);
347 		for (i = 0; grp->gr_mem[i]; i++)
348 			printf("%s%s", i ? "," : "", grp->gr_mem[i]);
349 		fputs("\n\n", stdout);
350 	}
351 	return EXIT_SUCCESS;
352 }
353