2 Unix SMB/Netbios implementation.
4 Copyright (C) Jeremy Allison 1998.
5 rewritten for version 2.0.6 by Tridge
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 extern int DEBUGLEVEL;
26 /* we are running this code in autoconf test mode to see which type of setuid
28 #if defined(HAVE_UNISTD_H)
33 #include <sys/types.h>
36 #ifdef HAVE_SYS_PRIV_H
43 #define DEBUG(x, y) printf y
44 #define smb_panic(x) exit(1)
48 /* are we running as non-root? This is used by the regresison test code,
49 and potentially also for sites that want non-root smbd */
50 static uid_t initial_uid;
51 static gid_t initial_gid;
53 /****************************************************************************
54 remember what uid we got started as - this allows us to run correctly
55 as non-root while catching trapdoor systems
56 ****************************************************************************/
59 initial_uid = geteuid();
60 initial_gid = getegid();
63 /****************************************************************************
64 some code (eg. winbindd) needs to know what uid we started as
65 ****************************************************************************/
66 uid_t sec_initial_uid(void)
71 /****************************************************************************
72 some code (eg. winbindd, profiling shm) needs to know what gid we started as
73 ****************************************************************************/
74 gid_t sec_initial_gid(void)
79 /****************************************************************************
80 are we running in non-root mode?
81 ****************************************************************************/
82 BOOL non_root_mode(void)
84 return (initial_uid != (uid_t)0);
87 /****************************************************************************
88 abort if we haven't set the uid correctly
89 ****************************************************************************/
90 static void assert_uid(uid_t ruid, uid_t euid)
92 if ((euid != (uid_t)-1 && geteuid() != euid) ||
93 (ruid != (uid_t)-1 && getuid() != ruid)) {
94 if (!non_root_mode()) {
95 DEBUG(0,("Failed to set uid privileges to (%d,%d) now set to (%d,%d)\n",
97 (int)getuid(), (int)geteuid()));
98 smb_panic("failed to set uid\n");
104 /****************************************************************************
105 abort if we haven't set the gid correctly
106 ****************************************************************************/
107 static void assert_gid(gid_t rgid, gid_t egid)
109 if ((egid != (gid_t)-1 && getegid() != egid) ||
110 (rgid != (gid_t)-1 && getgid() != rgid)) {
111 if (!non_root_mode()) {
112 DEBUG(0,("Failed to set gid privileges to (%d,%d) now set to (%d,%d) uid=(%d,%d)\n",
113 (int)rgid, (int)egid,
114 (int)getgid(), (int)getegid(),
115 (int)getuid(), (int)geteuid()));
116 smb_panic("failed to set gid\n");
122 /****************************************************************************
123 Gain root privilege before doing something.
124 We want to end up with ruid==euid==0
125 ****************************************************************************/
126 void gain_root_privilege(void)
141 setuidx(ID_EFFECTIVE, 0);
145 /* this is needed on some systems */
152 /****************************************************************************
153 Ensure our real and effective groups are zero.
154 we want to end up with rgid==egid==0
155 ****************************************************************************/
156 void gain_root_group_privilege(void)
171 setgidx(ID_EFFECTIVE, 0);
181 /****************************************************************************
182 Set *only* the effective uid.
183 we want to end up with ruid==0 and euid==uid
184 ****************************************************************************/
185 void set_effective_uid(uid_t uid)
188 setresuid(-1,uid,-1);
200 setuidx(ID_EFFECTIVE, uid);
206 /****************************************************************************
207 Set *only* the effective gid.
208 we want to end up with rgid==0 and egid==gid
209 ****************************************************************************/
210 void set_effective_gid(gid_t gid)
213 setresgid(-1,gid,-1);
225 setgidx(ID_EFFECTIVE, gid);
231 static uid_t saved_euid, saved_ruid;
233 /****************************************************************************
234 save the real and effective uid for later restoration. Used by the quotas
236 ****************************************************************************/
237 void save_re_uid(void)
239 saved_ruid = getuid();
240 saved_euid = geteuid();
244 /****************************************************************************
246 ****************************************************************************/
247 void restore_re_uid(void)
249 set_effective_uid(0);
252 setresuid(saved_ruid, saved_euid, -1);
254 setreuid(saved_ruid, -1);
255 setreuid(-1,saved_euid);
257 setuidx(ID_REAL, saved_ruid);
258 setuidx(ID_EFFECTIVE, saved_euid);
260 set_effective_uid(saved_euid);
261 if (getuid() != saved_ruid)
263 set_effective_uid(saved_euid);
266 assert_uid(saved_ruid, saved_euid);
269 /****************************************************************************
270 set the real AND effective uid to the current effective uid in a way that
271 allows root to be regained.
272 This is only possible on some platforms.
273 ****************************************************************************/
276 uid_t uid = geteuid();
279 setresuid(geteuid(), -1, -1);
298 assert_uid(uid, uid);
303 /****************************************************************************
304 Become the specified uid and gid - permanently !
305 there should be no way back if possible
306 ****************************************************************************/
307 void become_user_permanently(uid_t uid, gid_t gid)
310 * First - gain root privilege. We do this to ensure
311 * we can lose it again.
314 gain_root_privilege();
315 gain_root_group_privilege();
318 setresgid(gid,gid,gid);
320 setresuid(uid,uid,uid);
340 setgidx(ID_REAL, gid);
341 setgidx(ID_EFFECTIVE, gid);
343 setuidx(ID_REAL, uid);
344 setuidx(ID_EFFECTIVE, uid);
348 assert_uid(uid, uid);
349 assert_gid(gid, gid);
354 /****************************************************************************
355 this function just checks that we don't get ENOSYS back
356 ****************************************************************************/
357 static int have_syscall(void)
374 setuidx(ID_EFFECTIVE, -1);
377 if (errno == ENOSYS) return -1;
385 #if (defined(AIX) && defined(USE_SETREUID))
386 /* setreuid is badly broken on AIX 4.1, we avoid it completely */
387 fprintf(stderr,"avoiding possibly broken setreuid\n");
391 /* if not running as root then at least check to see if we get ENOSYS - this
392 handles Linux 2.0.x with glibc 2.1 */
393 fprintf(stderr,"not running as root: checking for ENOSYS\n");
394 exit(have_syscall());
397 gain_root_privilege();
398 gain_root_group_privilege();
399 set_effective_gid(1);
400 set_effective_uid(1);
403 gain_root_privilege();
404 gain_root_group_privilege();
405 become_user_permanently(1, 1);
408 fprintf(stderr,"uid not set permanently\n");