1/*-
2 * Copyright (c) 2002 Tim J. Robbins.
3 * 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 THE AUTHOR 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 THE AUTHOR 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/*
28 * newgrp -- change to a new group
29 */
30
31#include <sys/cdefs.h>
| 1/*-
2 * Copyright (c) 2002 Tim J. Robbins.
3 * 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 THE AUTHOR 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 THE AUTHOR 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/*
28 * newgrp -- change to a new group
29 */
30
31#include <sys/cdefs.h>
|
32__FBSDID("$FreeBSD: head/usr.bin/newgrp/newgrp.c 229668 2012-01-05 23:08:11Z ghelmer $");
| 32__FBSDID("$FreeBSD: head/usr.bin/newgrp/newgrp.c 231994 2012-02-22 06:27:20Z kevlo $");
|
33
34#include <sys/types.h>
35
36#include <err.h>
37#include <errno.h>
38#include <grp.h>
39#include <libgen.h>
40#include <limits.h>
41#include <login_cap.h>
42#include <paths.h>
43#include <pwd.h>
44#include <stdio.h>
45#include <stdlib.h>
46#include <string.h>
47#include <unistd.h>
48
49static void addgroup(const char *grpname);
50static void doshell(void);
51static int inarray(gid_t, const gid_t[], int);
52static void loginshell(void);
53static void restoregrps(void);
54static void usage(void);
55
56static struct passwd *pwd;
57static uid_t euid;
58
59extern char **environ;
60
61/* Manipulate effective user ID. */
62#define PRIV_START do { \
63 if (seteuid(euid) < 0) \
64 err(1, "seteuid"); \
65 } while (0)
66#define PRIV_END do { \
67 if (seteuid(getuid()) < 0) \
68 err(1, "seteuid"); \
69 } while (0)
70
71int
72main(int argc, char *argv[])
73{
74 int ch, login;
75
76 euid = geteuid();
77 if (seteuid(getuid()) < 0)
78 err(1, "seteuid");
79
80 if ((pwd = getpwuid(getuid())) == NULL)
81 errx(1, "unknown user");
82
83 login = 0;
84 while ((ch = getopt(argc, argv, "-l")) != -1) {
85 switch (ch) {
86 case '-': /* Obsolescent */
87 case 'l':
88 login = 1;
89 break;
90 default:
91 usage();
92 }
93 }
94 argc -= optind;
95 argv += optind;
96
97 switch (argc) {
98 case 0:
99 restoregrps();
100 break;
101 case 1:
102 addgroup(*argv);
103 break;
104 default:
105 usage();
106 }
107
108 if (seteuid(euid) < 0)
109 err(1, "seteuid");
110 if (setuid(getuid()) < 0)
111 err(1, "setuid");
112
113 if (login)
114 loginshell();
115 else
116 doshell();
117
118 /*NOTREACHED*/
119 exit(1);
120}
121
122static void
123usage(void)
124{
125
126 fprintf(stderr, "usage: newgrp [-l] [group]\n");
127 exit(1);
128}
129
130static void
131restoregrps(void)
132{
133 int initres, setres;
134
135 PRIV_START;
136 initres = initgroups(pwd->pw_name, pwd->pw_gid);
137 setres = setgid(pwd->pw_gid);
138 PRIV_END;
139
140 if (initres < 0)
141 warn("initgroups");
142 if (setres < 0)
143 warn("setgid");
144}
145
146static void
147addgroup(const char *grpname)
148{
149 gid_t *grps;
150 long lgid, ngrps_max;
151 int dbmember, i, ngrps;
152 gid_t egid;
153 struct group *grp;
| 33
34#include <sys/types.h>
35
36#include <err.h>
37#include <errno.h>
38#include <grp.h>
39#include <libgen.h>
40#include <limits.h>
41#include <login_cap.h>
42#include <paths.h>
43#include <pwd.h>
44#include <stdio.h>
45#include <stdlib.h>
46#include <string.h>
47#include <unistd.h>
48
49static void addgroup(const char *grpname);
50static void doshell(void);
51static int inarray(gid_t, const gid_t[], int);
52static void loginshell(void);
53static void restoregrps(void);
54static void usage(void);
55
56static struct passwd *pwd;
57static uid_t euid;
58
59extern char **environ;
60
61/* Manipulate effective user ID. */
62#define PRIV_START do { \
63 if (seteuid(euid) < 0) \
64 err(1, "seteuid"); \
65 } while (0)
66#define PRIV_END do { \
67 if (seteuid(getuid()) < 0) \
68 err(1, "seteuid"); \
69 } while (0)
70
71int
72main(int argc, char *argv[])
73{
74 int ch, login;
75
76 euid = geteuid();
77 if (seteuid(getuid()) < 0)
78 err(1, "seteuid");
79
80 if ((pwd = getpwuid(getuid())) == NULL)
81 errx(1, "unknown user");
82
83 login = 0;
84 while ((ch = getopt(argc, argv, "-l")) != -1) {
85 switch (ch) {
86 case '-': /* Obsolescent */
87 case 'l':
88 login = 1;
89 break;
90 default:
91 usage();
92 }
93 }
94 argc -= optind;
95 argv += optind;
96
97 switch (argc) {
98 case 0:
99 restoregrps();
100 break;
101 case 1:
102 addgroup(*argv);
103 break;
104 default:
105 usage();
106 }
107
108 if (seteuid(euid) < 0)
109 err(1, "seteuid");
110 if (setuid(getuid()) < 0)
111 err(1, "setuid");
112
113 if (login)
114 loginshell();
115 else
116 doshell();
117
118 /*NOTREACHED*/
119 exit(1);
120}
121
122static void
123usage(void)
124{
125
126 fprintf(stderr, "usage: newgrp [-l] [group]\n");
127 exit(1);
128}
129
130static void
131restoregrps(void)
132{
133 int initres, setres;
134
135 PRIV_START;
136 initres = initgroups(pwd->pw_name, pwd->pw_gid);
137 setres = setgid(pwd->pw_gid);
138 PRIV_END;
139
140 if (initres < 0)
141 warn("initgroups");
142 if (setres < 0)
143 warn("setgid");
144}
145
146static void
147addgroup(const char *grpname)
148{
149 gid_t *grps;
150 long lgid, ngrps_max;
151 int dbmember, i, ngrps;
152 gid_t egid;
153 struct group *grp;
|
154 char *ep, *pass;
| 154 char *ep, *pass, *cryptpw;
|
155 char **p;
156
157 egid = getegid();
158
159 /* Try it as a group name, then a group id. */
160 if ((grp = getgrnam(grpname)) == NULL)
161 if ((lgid = strtol(grpname, &ep, 10)) <= 0 || *ep != '\0' ||
162 (grp = getgrgid((gid_t)lgid)) == NULL ) {
163 warnx("%s: bad group name", grpname);
164 return;
165 }
166
167 /*
168 * If the user is not a member of the requested group and the group
169 * has a password, prompt and check it.
170 */
171 dbmember = 0;
172 if (pwd->pw_gid == grp->gr_gid)
173 dbmember = 1;
174 for (p = grp->gr_mem; *p != NULL; p++)
175 if (strcmp(*p, pwd->pw_name) == 0) {
176 dbmember = 1;
177 break;
178 }
179 if (!dbmember && *grp->gr_passwd != '\0' && getuid() != 0) {
180 pass = getpass("Password:");
| 155 char **p;
156
157 egid = getegid();
158
159 /* Try it as a group name, then a group id. */
160 if ((grp = getgrnam(grpname)) == NULL)
161 if ((lgid = strtol(grpname, &ep, 10)) <= 0 || *ep != '\0' ||
162 (grp = getgrgid((gid_t)lgid)) == NULL ) {
163 warnx("%s: bad group name", grpname);
164 return;
165 }
166
167 /*
168 * If the user is not a member of the requested group and the group
169 * has a password, prompt and check it.
170 */
171 dbmember = 0;
172 if (pwd->pw_gid == grp->gr_gid)
173 dbmember = 1;
174 for (p = grp->gr_mem; *p != NULL; p++)
175 if (strcmp(*p, pwd->pw_name) == 0) {
176 dbmember = 1;
177 break;
178 }
179 if (!dbmember && *grp->gr_passwd != '\0' && getuid() != 0) {
180 pass = getpass("Password:");
|
181 if (pass == NULL ||
182 strcmp(grp->gr_passwd, crypt(pass, grp->gr_passwd)) != 0) {
| 181 if (pass == NULL)
182 return;
183 cryptpw = crypt(pass, grp->gr_passwd);
184 if (cryptpw == NULL || strcmp(grp->gr_passwd, cryptpw) != 0) {
|
183 fprintf(stderr, "Sorry\n");
184 return;
185 }
186 }
187
188 ngrps_max = sysconf(_SC_NGROUPS_MAX) + 1;
189 if ((grps = malloc(sizeof(gid_t) * ngrps_max)) == NULL)
190 err(1, "malloc");
191 if ((ngrps = getgroups(ngrps_max, (gid_t *)grps)) < 0) {
192 warn("getgroups");
193 goto end;
194 }
195
196 /* Remove requested gid from supp. list if it exists. */
197 if (grp->gr_gid != egid && inarray(grp->gr_gid, grps, ngrps)) {
198 for (i = 0; i < ngrps; i++)
199 if (grps[i] == grp->gr_gid)
200 break;
201 ngrps--;
202 memmove(&grps[i], &grps[i + 1], (ngrps - i) * sizeof(gid_t));
203 PRIV_START;
204 if (setgroups(ngrps, (const gid_t *)grps) < 0) {
205 PRIV_END;
206 warn("setgroups");
207 goto end;
208 }
209 PRIV_END;
210 }
211
212 PRIV_START;
213 if (setgid(grp->gr_gid)) {
214 PRIV_END;
215 warn("setgid");
216 goto end;
217 }
218 PRIV_END;
219 grps[0] = grp->gr_gid;
220
221 /* Add old effective gid to supp. list if it does not exist. */
222 if (egid != grp->gr_gid && !inarray(egid, grps, ngrps)) {
223 if (ngrps == ngrps_max)
224 warnx("too many groups");
225 else {
226 grps[ngrps++] = egid;
227 PRIV_START;
228 if (setgroups(ngrps, (const gid_t *)grps)) {
229 PRIV_END;
230 warn("setgroups");
231 goto end;
232 }
233 PRIV_END;
234 }
235 }
236end:
237 free(grps);
238}
239
240static int
241inarray(gid_t gid, const gid_t grps[], int ngrps)
242{
243 int i;
244
245 for (i = 0; i < ngrps; i++)
246 if (grps[i] == gid)
247 return (1);
248 return (0);
249}
250
251/*
252 * Set the environment to what would be expected if the user logged in
253 * again; this performs the same steps as su(1)'s -l option.
254 */
255static void
256loginshell(void)
257{
258 char *args[2], **cleanenv, *term, *ticket;
259 const char *shell;
260 login_cap_t *lc;
261
262 shell = pwd->pw_shell;
263 if (*shell == '\0')
264 shell = _PATH_BSHELL;
265 if (chdir(pwd->pw_dir) < 0) {
266 warn("%s", pwd->pw_dir);
267 chdir("/");
268 }
269
270 term = getenv("TERM");
271 ticket = getenv("KRBTKFILE");
272
273 if ((cleanenv = calloc(20, sizeof(char *))) == NULL)
274 err(1, "calloc");
275 *cleanenv = NULL;
276 environ = cleanenv;
277
278 lc = login_getpwclass(pwd);
279 setusercontext(lc, pwd, pwd->pw_uid,
280 LOGIN_SETPATH|LOGIN_SETUMASK|LOGIN_SETENV);
281 login_close(lc);
282 setenv("USER", pwd->pw_name, 1);
283 setenv("SHELL", shell, 1);
284 setenv("HOME", pwd->pw_dir, 1);
285 if (term != NULL)
286 setenv("TERM", term, 1);
287 if (ticket != NULL)
288 setenv("KRBTKFILE", ticket, 1);
289
290 if (asprintf(args, "-%s", basename(shell)) < 0)
291 err(1, "asprintf");
292 args[1] = NULL;
293
294 execv(shell, args);
295 err(1, "%s", shell);
296}
297
298static void
299doshell(void)
300{
301 const char *shell;
302
303 shell = pwd->pw_shell;
304 if (*shell == '\0')
305 shell = _PATH_BSHELL;
306 execl(shell, basename(shell), (char *)NULL);
307 err(1, "%s", shell);
308}
| 185 fprintf(stderr, "Sorry\n");
186 return;
187 }
188 }
189
190 ngrps_max = sysconf(_SC_NGROUPS_MAX) + 1;
191 if ((grps = malloc(sizeof(gid_t) * ngrps_max)) == NULL)
192 err(1, "malloc");
193 if ((ngrps = getgroups(ngrps_max, (gid_t *)grps)) < 0) {
194 warn("getgroups");
195 goto end;
196 }
197
198 /* Remove requested gid from supp. list if it exists. */
199 if (grp->gr_gid != egid && inarray(grp->gr_gid, grps, ngrps)) {
200 for (i = 0; i < ngrps; i++)
201 if (grps[i] == grp->gr_gid)
202 break;
203 ngrps--;
204 memmove(&grps[i], &grps[i + 1], (ngrps - i) * sizeof(gid_t));
205 PRIV_START;
206 if (setgroups(ngrps, (const gid_t *)grps) < 0) {
207 PRIV_END;
208 warn("setgroups");
209 goto end;
210 }
211 PRIV_END;
212 }
213
214 PRIV_START;
215 if (setgid(grp->gr_gid)) {
216 PRIV_END;
217 warn("setgid");
218 goto end;
219 }
220 PRIV_END;
221 grps[0] = grp->gr_gid;
222
223 /* Add old effective gid to supp. list if it does not exist. */
224 if (egid != grp->gr_gid && !inarray(egid, grps, ngrps)) {
225 if (ngrps == ngrps_max)
226 warnx("too many groups");
227 else {
228 grps[ngrps++] = egid;
229 PRIV_START;
230 if (setgroups(ngrps, (const gid_t *)grps)) {
231 PRIV_END;
232 warn("setgroups");
233 goto end;
234 }
235 PRIV_END;
236 }
237 }
238end:
239 free(grps);
240}
241
242static int
243inarray(gid_t gid, const gid_t grps[], int ngrps)
244{
245 int i;
246
247 for (i = 0; i < ngrps; i++)
248 if (grps[i] == gid)
249 return (1);
250 return (0);
251}
252
253/*
254 * Set the environment to what would be expected if the user logged in
255 * again; this performs the same steps as su(1)'s -l option.
256 */
257static void
258loginshell(void)
259{
260 char *args[2], **cleanenv, *term, *ticket;
261 const char *shell;
262 login_cap_t *lc;
263
264 shell = pwd->pw_shell;
265 if (*shell == '\0')
266 shell = _PATH_BSHELL;
267 if (chdir(pwd->pw_dir) < 0) {
268 warn("%s", pwd->pw_dir);
269 chdir("/");
270 }
271
272 term = getenv("TERM");
273 ticket = getenv("KRBTKFILE");
274
275 if ((cleanenv = calloc(20, sizeof(char *))) == NULL)
276 err(1, "calloc");
277 *cleanenv = NULL;
278 environ = cleanenv;
279
280 lc = login_getpwclass(pwd);
281 setusercontext(lc, pwd, pwd->pw_uid,
282 LOGIN_SETPATH|LOGIN_SETUMASK|LOGIN_SETENV);
283 login_close(lc);
284 setenv("USER", pwd->pw_name, 1);
285 setenv("SHELL", shell, 1);
286 setenv("HOME", pwd->pw_dir, 1);
287 if (term != NULL)
288 setenv("TERM", term, 1);
289 if (ticket != NULL)
290 setenv("KRBTKFILE", ticket, 1);
291
292 if (asprintf(args, "-%s", basename(shell)) < 0)
293 err(1, "asprintf");
294 args[1] = NULL;
295
296 execv(shell, args);
297 err(1, "%s", shell);
298}
299
300static void
301doshell(void)
302{
303 const char *shell;
304
305 shell = pwd->pw_shell;
306 if (*shell == '\0')
307 shell = _PATH_BSHELL;
308 execl(shell, basename(shell), (char *)NULL);
309 err(1, "%s", shell);
310}
|