newgrp.c revision 1.4 1 /*-
2 * Copyright (c) 2007 The NetBSD Foundation, Inc.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to The NetBSD Foundation
6 * by Brian Ginsbach.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the NetBSD
19 * Foundation, Inc. and its contributors.
20 * 4. Neither the name of The NetBSD Foundation nor the names of its
21 * contributors may be used to endorse or promote products derived
22 * from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
25 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
26 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
27 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
28 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37 #include <sys/cdefs.h>
38
39 #ifndef lint
40 __RCSID("$NetBSD: newgrp.c,v 1.4 2007/10/17 21:07:49 christos Exp $");
41 #endif /* not lint */
42
43 #include <sys/param.h>
44 #include <sys/types.h>
45
46 #include <err.h>
47 #include <grp.h>
48 #include <libgen.h>
49 #include <paths.h>
50 #include <pwd.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <unistd.h>
55
56 #ifdef LOGIN_CAP
57 #include <login_cap.h>
58 #endif
59
60 #include "grutil.h"
61
62 static void
63 usage(void)
64 {
65 (void)fprintf(stderr, "usage: %s [-l] [group]\n", getprogname());
66 exit(EXIT_FAILURE);
67 }
68
69 int
70 main(int argc, char *argv[])
71 {
72 extern char **environ;
73 struct passwd *pwd;
74 int c, lflag;
75 char *shell, sbuf[MAXPATHLEN + 2];
76 uid_t uid;
77 #ifdef LOGIN_CAP
78 login_cap_t *lc;
79 u_int flags = LOGIN_SETUSER;
80 #endif
81
82 uid = getuid();
83 pwd = getpwuid(uid);
84 if (pwd == NULL)
85 errx(EXIT_FAILURE, "who are you?");
86
87 #ifdef LOGIN_CAP
88 if ((lc = login_getclass(pwd->pw_class)) == NULL)
89 errx(EXIT_FAILURE, "%s: unknown login class", pwd->pw_class);
90 #endif
91
92 lflag = 0;
93 while ((c = getopt(argc, argv, "-l")) != -1) {
94 switch (c) {
95 case '-':
96 case 'l':
97 if (lflag)
98 usage();
99 lflag = 1;
100 break;
101 default:
102 usage();
103 break;
104 }
105 }
106
107 argc -= optind;
108 argv += optind;
109
110 if (argc > 0) {
111 #if 0
112 pwd->pw_gid = newgrp(*argv, pwd);
113 addgrp(pwd->pw_gid);
114 if (setgid(pwd->pw_gid) < 0)
115 err(1, "setgid");
116 #endif
117 #ifdef LOGIN_CAP
118 addgroup(lc, *argv, pwd, getuid(), "Password:");
119 #else
120 addgroup(*argv, pwd, getuid(), "Password:");
121 #endif
122 } else {
123 #ifdef LOGIN_CAP
124 flags |= LOGIN_SETGROUP;
125 #else
126 if (initgroups(pwd->pw_name, pwd->pw_gid) == -1)
127 err(EXIT_FAILURE, "initgroups");
128 if (setgid(pwd->pw_gid) == -1)
129 err(EXIT_FAILURE, "setgid");
130 #endif
131 }
132
133 #ifdef LOGIN_CAP
134 if (setusercontext(lc, pwd, uid, flags) == -1)
135 err(EXIT_FAILURE, "setusercontext");
136 if (!lflag)
137 login_close(lc);
138 #else
139 if (setuid(pwd->pw_uid) == -1)
140 err(EXIT_FAILURE, "setuid");
141 #endif
142
143 if (*pwd->pw_shell == '\0') {
144 #ifdef TRUST_ENV_SHELL
145 shell = getenv("SHELL");
146 if (shell != NULL)
147 pwd->pw_shell = shell;
148 else
149 #endif
150 pwd->pw_shell = __UNCONST(_PATH_BSHELL);
151 }
152
153 shell = pwd->pw_shell;
154
155 if (lflag) {
156 char *term;
157 #ifdef KERBEROS
158 char *krbtkfile;
159 #endif
160
161 if (chdir(pwd->pw_dir) == -1)
162 warn("%s", pwd->pw_dir);
163
164 term = getenv("TERM");
165 #ifdef KERBEROS
166 krbtkfile = getenv("KRBTKFILE");
167 #endif
168
169 /* create an empty environment */
170 if ((environ = malloc(sizeof(char *))) == NULL)
171 err(EXIT_FAILURE, NULL);
172 environ[0] = NULL;
173 #ifdef LOGIN_CAP
174 if (setusercontext(lc, pwd, uid, LOGIN_SETENV | LOGIN_SETPATH) == -1)
175 err(EXIT_FAILURE, "setusercontext");
176 login_close(lc);
177 #else
178 (void)setenv("PATH", _PATH_DEFPATH, 1);
179 #endif
180 if (term != NULL)
181 (void)setenv("TERM", term, 1);
182 #ifdef KERBEROS
183 if (krbtkfile != NULL)
184 (void)setenv("KRBTKFILE", krbtkfile, 1);
185 #endif
186
187 (void)setenv("LOGNAME", pwd->pw_name, 1);
188 (void)setenv("USER", pwd->pw_name, 1);
189 (void)setenv("HOME", pwd->pw_dir, 1);
190 (void)setenv("SHELL", pwd->pw_shell, 1);
191
192 sbuf[0] = '-';
193 (void)strlcpy(sbuf + 1, basename(pwd->pw_shell),
194 sizeof(sbuf) - 1);
195 shell = sbuf;
196 }
197
198 (void)execl(pwd->pw_shell, shell, NULL);
199 err(EXIT_FAILURE, "%s", pwd->pw_shell);
200 /* NOTREACHED */
201 }
202