masqmail-0.2

view src/permissions.c @ 51:8a92de5e8907

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fixed inverted condition for undefined online_file reported by Juergen Daubert via mailing list the bug was introduced by refactoring (seems we need automated testing)
author meillo@marmaro.de
date Fri, 21 May 2010 14:45:56 +0200
parents 26e34ae9a3e3
children ffeff2c33799
line source
1 /* MasqMail
2 Copyright (C) 2000 Oliver Kurth
3
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.
8
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.
13
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 */
18
19 #include <pwd.h>
20 #include <grp.h>
21
22 #include "masqmail.h"
23
24 /* is there really no function in libc for this? */
25 gboolean
26 is_ingroup(uid_t uid, gid_t gid)
27 {
28 struct group *grent = getgrgid(gid);
29
30 if (grent) {
31 struct passwd *pwent = getpwuid(uid);
32 if (pwent) {
33 char *entry;
34 int i = 0;
35 while ((entry = grent->gr_mem[i++])) {
36 if (strcmp(pwent->pw_name, entry) == 0)
37 return TRUE;
38 }
39 }
40 }
41 return FALSE;
42 }
43
44 gboolean
45 is_privileged_user(uid_t uid)
46 {
47 return (uid == 0) || (uid == conf.mail_uid) || (is_ingroup(uid, conf.mail_gid));
48 }
49
50 void
51 set_euidgid(gint uid, gint gid, uid_t * old_uid, gid_t * old_gid)
52 {
53 if (old_uid)
54 *old_uid = geteuid();
55 if (old_gid)
56 *old_gid = getegid();
57
58 seteuid(0);
59
60 if (setegid(gid) != 0) {
61 logwrite(LOG_ALERT, "could not change gid to %d: %s\n", gid, strerror(errno));
62 exit(EXIT_FAILURE);
63 }
64 if (seteuid(uid) != 0) {
65 logwrite(LOG_ALERT, "could not change uid to %d: %s\n", uid, strerror(errno));
66 exit(EXIT_FAILURE);
67 }
68 }
69
70 void
71 set_identity(uid_t old_uid, gchar * task_name)
72 {
73 if (!conf.run_as_user) {
74 if (!is_privileged_user(old_uid)) {
75 fprintf(stderr, "must be root, %s or in group %s for %s.\n", DEF_MAIL_USER, DEF_MAIL_GROUP, task_name);
76 exit(EXIT_FAILURE);
77 }
78
79 set_euidgid(conf.mail_uid, conf.mail_gid, NULL, NULL);
80 }
81 }