xref: /freebsd/usr.sbin/pw/pw_group.c (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
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 	"$Id$";
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 #include "pwupd.h"
40 
41 
42 static int      print_group(struct group * grp, int pretty);
43 static gid_t    gr_gidpolicy(struct userconf * cnf, struct cargs * args);
44 
45 int
46 pw_group(struct userconf * cnf, int mode, struct cargs * args)
47 {
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 	/*
64 	 * With M_NEXT, we only need to return the
65 	 * next gid to stdout
66 	 */
67 	if (mode == M_NEXT)
68 	{
69 		gid_t next = gr_gidpolicy(cnf, args);
70 		if (getarg(args, 'q'))
71 			return next;
72 		printf("%ld\n", (long)next);
73 		return EXIT_SUCCESS;
74 	}
75 
76 	if (mode == M_PRINT && getarg(args, 'a')) {
77 		int             pretty = getarg(args, 'P') != NULL;
78 
79 		setgrent();
80 		while ((grp = getgrent()) != NULL)
81 			print_group(grp, pretty);
82 		endgrent();
83 		return EXIT_SUCCESS;
84 	}
85 	if (a_gid == NULL) {
86 		if (a_name == NULL)
87 			errx(EX_DATAERR, "group name or id required");
88 
89 		if (mode != M_ADD && grp == NULL && isdigit(*a_name->val)) {
90 			(a_gid = a_name)->ch = 'g';
91 			a_name = NULL;
92 		}
93 	}
94 	grp = (a_name != NULL) ? getgrnam(a_name->val) : getgrgid((gid_t) atoi(a_gid->val));
95 
96 	if (mode == M_UPDATE || mode == M_DELETE || mode == M_PRINT) {
97 		if (a_name == NULL && grp == NULL)	/* Try harder */
98 			grp = getgrgid(atoi(a_gid->val));
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 = a_name ? a_name->val : "nogroup";
105 				fakegroup.gr_gid = a_gid ? (gid_t) atol(a_gid->val) : -1;
106 				fakegroup.gr_mem = fmems;
107 				return print_group(&fakegroup, getarg(args, 'P') != NULL);
108 			}
109 			errx(EX_DATAERR, "unknown group `%s'", a_name ? a_name->val : a_gid->val);
110 		}
111 		if (a_name == NULL)	/* Needed later */
112 			a_name = addarg(args, 'n', grp->gr_name);
113 
114 		/*
115 		 * Handle deletions now
116 		 */
117 		if (mode == M_DELETE) {
118 			gid_t           gid = grp->gr_gid;
119 
120 			if (delgrent(grp) == -1)
121 				err(EX_IOERR, "error updating group file");
122 			pw_log(cnf, mode, W_GROUP, "%s(%ld) removed", a_name->val, (long) gid);
123 			return EXIT_SUCCESS;
124 		} else if (mode == M_PRINT)
125 			return print_group(grp, getarg(args, 'P') != NULL);
126 
127 		if (a_gid)
128 			grp->gr_gid = (gid_t) atoi(a_gid->val);
129 
130 		if ((arg = getarg(args, 'l')) != NULL)
131 			grp->gr_name = pw_checkname((u_char *)arg->val, 0);
132 	} else {
133 		if (a_name == NULL)	/* Required */
134 			errx(EX_DATAERR, "group name required");
135 		else if (grp != NULL)	/* Exists */
136 			errx(EX_DATAERR, "group name `%s' already exists", a_name->val);
137 
138 		extendarray(&members, &grmembers, 200);
139 		members[0] = NULL;
140 		grp = &fakegroup;
141 		grp->gr_name = pw_checkname((u_char *)a_name->val, 0);
142 		grp->gr_passwd = "*";
143 		grp->gr_gid = gr_gidpolicy(cnf, args);
144 		grp->gr_mem = members;
145 	}
146 
147 	/*
148 	 * This allows us to set a group password Group passwords is an
149 	 * antique idea, rarely used and insecure (no secure database) Should
150 	 * be discouraged, but it is apparently still supported by some
151 	 * software.
152 	 */
153 
154 	if ((arg = getarg(args, 'h')) != NULL) {
155 		if (strcmp(arg->val, "-") == 0)
156 			grp->gr_passwd = "*";	/* No access */
157 		else {
158 			int             fd = atoi(arg->val);
159 			int             b;
160 			int             istty = isatty(fd);
161 			struct termios  t;
162 			char           *p, line[256];
163 
164 			if (istty) {
165 				if (tcgetattr(fd, &t) == -1)
166 					istty = 0;
167 				else {
168 					struct termios  n = t;
169 
170 					/* Disable echo */
171 					n.c_lflag &= ~(ECHO);
172 					tcsetattr(fd, TCSANOW, &n);
173 					printf("%sassword for group %s:", (mode == M_UPDATE) ? "New p" : "P", grp->gr_name);
174 					fflush(stdout);
175 				}
176 			}
177 			b = read(fd, line, sizeof(line) - 1);
178 			if (istty) {	/* Restore state */
179 				tcsetattr(fd, TCSANOW, &t);
180 				fputc('\n', stdout);
181 				fflush(stdout);
182 			}
183 			if (b < 0) {
184 				warn("-h file descriptor");
185 				return EX_OSERR;
186 			}
187 			line[b] = '\0';
188 			if ((p = strpbrk(line, " \t\r\n")) != NULL)
189 				*p = '\0';
190 			if (!*line)
191 				errx(EX_DATAERR, "empty password read on file descriptor %d", fd);
192 			grp->gr_passwd = pw_pwcrypt(line);
193 		}
194 	}
195 
196 	if (((arg = getarg(args, 'M')) != NULL || (arg = getarg(args, 'm')) != NULL) && arg->val) {
197 		int	i = 0;
198 		char   *p;
199 		struct passwd	*pwd;
200 
201 		/* Make sure this is not stay NULL with -M "" */
202 		extendarray(&members, &grmembers, 200);
203 		if (arg->ch == 'm') {
204 			int	k = 0;
205 
206 			while (grp->gr_mem[k] != NULL) {
207 				if (extendarray(&members, &grmembers, i + 2) != -1) {
208 					members[i++] = grp->gr_mem[k];
209 				}
210 				k++;
211 			}
212 		}
213 		for (p = strtok(arg->val, ", \t"); p != NULL; p = strtok(NULL, ", \t")) {
214 			int     j;
215 			if ((pwd = getpwnam(p)) == NULL) {
216 				if (!isdigit(*p) || (pwd = getpwuid((uid_t) atoi(p))) == NULL)
217 					errx(EX_NOUSER, "user `%s' does not exist", p);
218 			}
219 			/*
220 			 * Check for duplicates
221 			 */
222 			for (j = 0; j < i && strcmp(members[j], pwd->pw_name)!=0; j++)
223 				;
224 			if (j == i && extendarray(&members, &grmembers, i + 2) != -1)
225 				members[i++] = newstr(pwd->pw_name);
226 		}
227 		while (i < grmembers)
228 			members[i++] = NULL;
229 		grp->gr_mem = members;
230 	}
231 
232 	if (getarg(args, 'N') != NULL)
233 		return print_group(grp, getarg(args, 'P') != NULL);
234 
235 	if ((mode == M_ADD && !addgrent(grp)) || (mode == M_UPDATE && !chggrent(a_name->val, grp))) {
236 		warn("group update");
237 		return EX_IOERR;
238 	}
239 	/* grp may have been invalidated */
240 	if ((grp = getgrnam(a_name->val)) == NULL)
241 		errx(EX_SOFTWARE, "group disappeared during update");
242 
243 	pw_log(cnf, mode, W_GROUP, "%s(%ld)", grp->gr_name, (long) grp->gr_gid);
244 
245 	if (members)
246 		free(members);
247 
248 	return EXIT_SUCCESS;
249 }
250 
251 
252 static          gid_t
253 gr_gidpolicy(struct userconf * cnf, struct cargs * args)
254 {
255 	struct group   *grp;
256 	gid_t           gid = (gid_t) - 1;
257 	struct carg    *a_gid = getarg(args, 'g');
258 
259 	/*
260 	 * Check the given gid, if any
261 	 */
262 	if (a_gid != NULL) {
263 		gid = (gid_t) atol(a_gid->val);
264 
265 		if ((grp = getgrgid(gid)) != NULL && getarg(args, 'o') == NULL)
266 			errx(EX_DATAERR, "gid `%ld' has already been allocated", (long) grp->gr_gid);
267 	} else {
268 		struct bitmap   bm;
269 
270 		/*
271 		 * We need to allocate the next available gid under one of
272 		 * two policies a) Grab the first unused gid b) Grab the
273 		 * highest possible unused gid
274 		 */
275 		if (cnf->min_gid >= cnf->max_gid) {	/* Sanity claus^H^H^H^Hheck */
276 			cnf->min_gid = 1000;
277 			cnf->max_gid = 32000;
278 		}
279 		bm = bm_alloc(cnf->max_gid - cnf->min_gid + 1);
280 
281 		/*
282 		 * Now, let's fill the bitmap from the password file
283 		 */
284 		setgrent();
285 		while ((grp = getgrent()) != NULL)
286 			if (grp->gr_gid >= (int) cnf->min_gid && grp->gr_gid <= (int) cnf->max_gid)
287 				bm_setbit(&bm, grp->gr_gid - cnf->min_gid);
288 		endgrent();
289 
290 		/*
291 		 * Then apply the policy, with fallback to reuse if necessary
292 		 */
293 		if (cnf->reuse_gids)
294 			gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
295 		else {
296 			gid = (gid_t) (bm_lastset(&bm) + 1);
297 			if (!bm_isset(&bm, gid))
298 				gid += cnf->min_gid;
299 			else
300 				gid = (gid_t) (bm_firstunset(&bm) + cnf->min_gid);
301 		}
302 
303 		/*
304 		 * Another sanity check
305 		 */
306 		if (gid < cnf->min_gid || gid > cnf->max_gid)
307 			errx(EX_SOFTWARE, "unable to allocate a new gid - range fully used");
308 		bm_dealloc(&bm);
309 	}
310 	return gid;
311 }
312 
313 
314 static int
315 print_group(struct group * grp, int pretty)
316 {
317 	if (!pretty) {
318 		int		buflen = 0;
319 		char           *buf = NULL;
320 
321 		fmtgrent(&buf, &buflen, grp);
322 		fputs(buf, stdout);
323 		free(buf);
324 	} else {
325 		int             i;
326 
327 		printf("Group Name: %-15s   #%lu\n"
328 		       "   Members: ",
329 		       grp->gr_name, (long) grp->gr_gid);
330 		for (i = 0; grp->gr_mem[i]; i++)
331 			printf("%s%s", i ? "," : "", grp->gr_mem[i]);
332 		fputs("\n\n", stdout);
333 	}
334 	return EXIT_SUCCESS;
335 }
336