masqmail-0.2

view src/permissions.c @ 12:9fb7ddbaf129

removed noop-code; some beautifying
author meillo@marmaro.de
date Wed, 29 Oct 2008 16:34:13 +0100
parents 08114f7dcc23
children f671821d8222
line source
1 /* MasqMail
2 Copyright (C) 2000 Oliver Kurth
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
19 #include "masqmail.h"
20 #include <pwd.h>
21 #include <grp.h>
23 /* is there really no function in libc for this? */
24 gboolean
25 is_ingroup(uid_t uid, gid_t gid)
26 {
27 struct group *grent = getgrgid(gid);
29 if (grent) {
30 struct passwd *pwent = getpwuid(uid);
31 if (pwent) {
32 char *entry;
33 int i = 0;
34 while ((entry = grent->gr_mem[i++])) {
35 if (strcmp(pwent->pw_name, entry) == 0)
36 return TRUE;
37 }
38 }
39 }
40 return FALSE;
41 }
43 gboolean
44 is_privileged_user(uid_t uid)
45 {
46 return (uid == 0) || (uid == conf.mail_uid) || (is_ingroup(uid, conf.mail_gid));
47 }
49 void
50 set_euidgid(gint uid, gint gid, uid_t * old_uid, gid_t * old_gid)
51 {
52 if (old_uid)
53 *old_uid = geteuid();
54 if (old_gid)
55 *old_gid = getegid();
57 seteuid(0);
59 if (setegid(gid) != 0) {
60 logwrite(LOG_ALERT, "could not change gid to %d: %s\n", gid, strerror(errno));
61 exit(EXIT_FAILURE);
62 }
63 if (seteuid(uid) != 0) {
64 logwrite(LOG_ALERT, "could not change uid to %d: %s\n", uid, strerror(errno));
65 exit(EXIT_FAILURE);
66 }
67 }
69 void
70 set_identity(uid_t old_uid, gchar * task_name)
71 {
72 if (!conf.run_as_user) {
73 if (!is_privileged_user(old_uid)) {
74 fprintf(stderr, "must be root, %s or in group %s for %s.\n", DEF_MAIL_USER, DEF_MAIL_GROUP, task_name);
75 exit(EXIT_FAILURE);
76 }
78 set_euidgid(conf.mail_uid, conf.mail_gid, NULL, NULL);
79 }
80 }