xref: /freebsd/usr.sbin/pw/pw_group.c (revision a35d88931c87cfe6bd38f01d7bad22140b3b38f3)
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((unsigned char)*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 	    (arg = getarg(args, 'H')) != NULL) {
163 		if (strcmp(arg->val, "-") == 0)
164 			grp->gr_passwd = "*";	/* No access */
165 		else {
166 			int             fd = atoi(arg->val);
167 			int		precrypt = (arg->ch == 'H');
168 			int             b;
169 			int             istty = isatty(fd);
170 			struct termios  t;
171 			char           *p, line[256];
172 
173 			if (istty) {
174 				if (tcgetattr(fd, &t) == -1)
175 					istty = 0;
176 				else {
177 					struct termios  n = t;
178 
179 					/* Disable echo */
180 					n.c_lflag &= ~(ECHO);
181 					tcsetattr(fd, TCSANOW, &n);
182 					printf("%sassword for group %s:", (mode == M_UPDATE) ? "New p" : "P", grp->gr_name);
183 					fflush(stdout);
184 				}
185 			}
186 			b = read(fd, line, sizeof(line) - 1);
187 			if (istty) {	/* Restore state */
188 				tcsetattr(fd, TCSANOW, &t);
189 				fputc('\n', stdout);
190 				fflush(stdout);
191 			}
192 			if (b < 0) {
193 				warn("-h file descriptor");
194 				return EX_OSERR;
195 			}
196 			line[b] = '\0';
197 			if ((p = strpbrk(line, " \t\r\n")) != NULL)
198 				*p = '\0';
199 			if (!*line)
200 				errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
201 			if (precrypt) {
202 				if (strchr(line, ':') != NULL)
203 					return EX_DATAERR;
204 				grp->gr_passwd = line;
205 			} else
206 				grp->gr_passwd = pw_pwcrypt(line);
207 		}
208 	}
209 
210 	if (((arg = getarg(args, 'M')) != NULL || (arg = getarg(args, 'm')) != NULL) && arg->val) {
211 		int	i = 0;
212 		char   *p;
213 		struct passwd	*pwd;
214 
215 		/* Make sure this is not stay NULL with -M "" */
216 		extendarray(&members, &grmembers, 200);
217 		if (arg->ch == 'm') {
218 			int	k = 0;
219 
220 			while (grp->gr_mem[k] != NULL) {
221 				if (extendarray(&members, &grmembers, i + 2) != -1) {
222 					members[i++] = grp->gr_mem[k];
223 				}
224 				k++;
225 			}
226 		}
227 		for (p = strtok(arg->val, ", \t"); p != NULL; p = strtok(NULL, ", \t")) {
228 			int     j;
229 			if ((pwd = GETPWNAM(p)) == NULL) {
230 				if (!isdigit((unsigned char)*p) || (pwd = getpwuid((uid_t) atoi(p))) == NULL)
231 					errx(EX_NOUSER, "user `%s' does not exist", p);
232 			}
233 			/*
234 			 * Check for duplicates
235 			 */
236 			for (j = 0; j < i && strcmp(members[j], pwd->pw_name)!=0; j++)
237 				;
238 			if (j == i && extendarray(&members, &grmembers, i + 2) != -1)
239 				members[i++] = newstr(pwd->pw_name);
240 		}
241 		while (i < grmembers)
242 			members[i++] = NULL;
243 		grp->gr_mem = members;
244 	}
245 
246 	if (getarg(args, 'N') != NULL)
247 		return print_group(grp, getarg(args, 'P') != NULL);
248 
249 	if (mode == M_ADD && (rc = addgrent(grp)) != 0) {
250 		if (rc == -1)
251 			warnx("group '%s' already exists", grp->gr_name);
252 		else
253 			warn("group update");
254 		return EX_IOERR;
255 	} else if (mode == M_UPDATE && (rc = chggrent(a_name->val, grp)) != 0) {
256 		if (rc == -1)
257 			warnx("group '%s' not available (NIS?)", grp->gr_name);
258 		else
259 			warn("group update");
260 		return EX_IOERR;
261 	}
262 	/* grp may have been invalidated */
263 	if ((grp = GETGRNAM(a_name->val)) == NULL)
264 		errx(EX_SOFTWARE, "group disappeared during update");
265 
266 	pw_log(cnf, mode, W_GROUP, "%s(%ld)", grp->gr_name, (long) grp->gr_gid);
267 
268 	if (members)
269 		free(members);
270 
271 	return EXIT_SUCCESS;
272 }
273 
274 
275 static          gid_t
276 gr_gidpolicy(struct userconf * cnf, struct cargs * args)
277 {
278 	struct group   *grp;
279 	gid_t           gid = (gid_t) - 1;
280 	struct carg    *a_gid = getarg(args, 'g');
281 
282 	/*
283 	 * Check the given gid, if any
284 	 */
285 	if (a_gid != NULL) {
286 		gid = (gid_t) atol(a_gid->val);
287 
288 		if ((grp = GETGRGID(gid)) != NULL && getarg(args, 'o') == NULL)
289 			errx(EX_DATAERR, "gid `%ld' has already been allocated", (long) grp->gr_gid);
290 	} else {
291 		struct bitmap   bm;
292 
293 		/*
294 		 * We need to allocate the next available gid under one of
295 		 * two policies a) Grab the first unused gid b) Grab the
296 		 * highest possible unused gid
297 		 */
298 		if (cnf->min_gid >= cnf->max_gid) {	/* Sanity claus^H^H^H^Hheck */
299 			cnf->min_gid = 1000;
300 			cnf->max_gid = 32000;
301 		}
302 		bm = bm_alloc(cnf->max_gid - cnf->min_gid + 1);
303 
304 		/*
305 		 * Now, let's fill the bitmap from the password file
306 		 */
307 		SETGRENT();
308 		while ((grp = GETGRENT()) != NULL)
309 			if ((gid_t)grp->gr_gid >= (gid_t)cnf->min_gid &&
310                             (gid_t)grp->gr_gid <= (gid_t)cnf->max_gid)
311 				bm_setbit(&bm, grp->gr_gid - cnf->min_gid);
312 		ENDGRENT();
313 
314 		/*
315 		 * Then apply the policy, with fallback to reuse if necessary
316 		 */
317 		if (cnf->reuse_gids)
318 			gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
319 		else {
320 			gid = (gid_t) (bm_lastset(&bm) + 1);
321 			if (!bm_isset(&bm, gid))
322 				gid += cnf->min_gid;
323 			else
324 				gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
325 		}
326 
327 		/*
328 		 * Another sanity check
329 		 */
330 		if (gid < cnf->min_gid || gid > cnf->max_gid)
331 			errx(EX_SOFTWARE, "unable to allocate a new gid - range fully used");
332 		bm_dealloc(&bm);
333 	}
334 	return gid;
335 }
336 
337 
338 static int
339 print_group(struct group * grp, int pretty)
340 {
341 	if (!pretty) {
342 		int		buflen = 0;
343 		char           *buf = NULL;
344 
345 		fmtgrent(&buf, &buflen, grp);
346 		fputs(buf, stdout);
347 		free(buf);
348 	} else {
349 		int             i;
350 
351 		printf("Group Name: %-15s   #%lu\n"
352 		       "   Members: ",
353 		       grp->gr_name, (long) grp->gr_gid);
354 		for (i = 0; grp->gr_mem[i]; i++)
355 			printf("%s%s", i ? "," : "", grp->gr_mem[i]);
356 		fputs("\n\n", stdout);
357 	}
358 	return EXIT_SUCCESS;
359 }
360