masqmail

annotate src/permissions.c @ 256:d4d0defaf769

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updated ChangeLog
author markus schnalke <meillo@marmaro.de>
date Thu, 04 Nov 2010 14:57:53 -0300
parents 3cbcc46c7d49
children fc1c6425c024
rev   line source
meillo@0 1 /* MasqMail
meillo@0 2 Copyright (C) 2000 Oliver Kurth
meillo@224 3 Copyright (C) 2010 markus schnalke <meillo@marmaro.de>
meillo@0 4
meillo@0 5 This program is free software; you can redistribute it and/or modify
meillo@0 6 it under the terms of the GNU General Public License as published by
meillo@0 7 the Free Software Foundation; either version 2 of the License, or
meillo@0 8 (at your option) any later version.
meillo@0 9
meillo@0 10 This program is distributed in the hope that it will be useful,
meillo@0 11 but WITHOUT ANY WARRANTY; without even the implied warranty of
meillo@0 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
meillo@0 13 GNU General Public License for more details.
meillo@0 14
meillo@0 15 You should have received a copy of the GNU General Public License
meillo@0 16 along with this program; if not, write to the Free Software
meillo@0 17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
meillo@0 18 */
meillo@0 19
meillo@0 20 #include <pwd.h>
meillo@0 21 #include <grp.h>
meillo@0 22
meillo@15 23 #include "masqmail.h"
meillo@15 24
meillo@0 25 /* is there really no function in libc for this? */
meillo@10 26 gboolean
meillo@10 27 is_ingroup(uid_t uid, gid_t gid)
meillo@0 28 {
meillo@10 29 struct group *grent = getgrgid(gid);
meillo@84 30 struct passwd *pwent = getpwuid(uid);
meillo@84 31 char *entry;
meillo@84 32 int i = 0;
meillo@0 33
meillo@84 34 if (!grent) {
meillo@84 35 return FALSE;
meillo@84 36 }
meillo@84 37 if (!pwent) {
meillo@84 38 return FALSE;
meillo@84 39 }
meillo@84 40 /* check primary group */
meillo@84 41 if (pwent->pw_gid == gid) {
meillo@84 42 return TRUE;
meillo@84 43 }
meillo@84 44 /* check secondary groups */
meillo@84 45 while ((entry = grent->gr_mem[i++])) {
meillo@84 46 if (strcmp(pwent->pw_name, entry) == 0)
meillo@84 47 return TRUE;
meillo@10 48 }
meillo@10 49 return FALSE;
meillo@0 50 }
meillo@0 51
meillo@10 52 gboolean
meillo@10 53 is_privileged_user(uid_t uid)
meillo@0 54 {
meillo@87 55 /* uncomment these lines if you need the `uucp' group to be trusted too
meillo@87 56 struct group* grent = getgrnam("uucp");
meillo@87 57
meillo@87 58 if (is_ingroup(uid, grent->gr_gid)) {
meillo@87 59 return TRUE;
meillo@87 60 }
meillo@87 61 */
meillo@87 62
meillo@10 63 return (uid == 0) || (uid == conf.mail_uid) || (is_ingroup(uid, conf.mail_gid));
meillo@0 64 }
meillo@0 65
meillo@10 66 void
meillo@10 67 set_euidgid(gint uid, gint gid, uid_t * old_uid, gid_t * old_gid)
meillo@0 68 {
meillo@10 69 if (old_uid)
meillo@10 70 *old_uid = geteuid();
meillo@10 71 if (old_gid)
meillo@10 72 *old_gid = getegid();
meillo@0 73
meillo@10 74 seteuid(0);
meillo@0 75
meillo@10 76 if (setegid(gid) != 0) {
meillo@10 77 logwrite(LOG_ALERT, "could not change gid to %d: %s\n", gid, strerror(errno));
meillo@10 78 exit(EXIT_FAILURE);
meillo@10 79 }
meillo@10 80 if (seteuid(uid) != 0) {
meillo@10 81 logwrite(LOG_ALERT, "could not change uid to %d: %s\n", uid, strerror(errno));
meillo@10 82 exit(EXIT_FAILURE);
meillo@10 83 }
meillo@0 84 }
meillo@0 85
meillo@10 86 void
meillo@10 87 set_identity(uid_t old_uid, gchar * task_name)
meillo@0 88 {
meillo@10 89 if (!conf.run_as_user) {
meillo@10 90 if (!is_privileged_user(old_uid)) {
meillo@10 91 fprintf(stderr, "must be root, %s or in group %s for %s.\n", DEF_MAIL_USER, DEF_MAIL_GROUP, task_name);
meillo@10 92 exit(EXIT_FAILURE);
meillo@10 93 }
meillo@0 94
meillo@10 95 set_euidgid(conf.mail_uid, conf.mail_gid, NULL, NULL);
meillo@10 96 }
meillo@0 97 }