2 * Copyright (c) 1982, 1986, 1989, 1990, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
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28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * @(#)kern_prot.c 8.6 (Berkeley) 1/21/94
39 * $FreeBSD: src/sys/kern/kern_prot.c,v 1.53.2.9 2002/03/09 05:20:26 dd Exp $
40 * $DragonFly: src/sys/kern/kern_prot.c,v 1.29 2008/02/16 15:53:39 matthias Exp $
44 * System calls related to processes and protection
47 #include "opt_compat.h"
49 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/sysproto.h>
53 #include <sys/kernel.h>
57 #include <sys/malloc.h>
58 #include <sys/pioctl.h>
59 #include <sys/resourcevar.h>
61 #include <sys/lockf.h>
62 #include <sys/spinlock.h>
64 #include <sys/thread2.h>
65 #include <sys/spinlock2.h>
67 static MALLOC_DEFINE(M_CRED
, "cred", "credentials");
70 * NOT MP SAFE due to p_pptr access
74 sys_getpid(struct getpid_args
*uap
)
76 struct proc
*p
= curproc
;
78 uap
->sysmsg_fds
[0] = p
->p_pid
;
79 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
80 uap
->sysmsg_fds
[1] = p
->p_pptr
->p_pid
;
87 sys_getppid(struct getppid_args
*uap
)
89 struct proc
*p
= curproc
;
91 uap
->sysmsg_result
= p
->p_pptr
->p_pid
;
97 sys_lwp_gettid(struct lwp_gettid_args
*uap
)
99 struct lwp
*lp
= curthread
->td_lwp
;
101 uap
->sysmsg_result
= lp
->lwp_tid
;
106 * Get process group ID; note that POSIX getpgrp takes no parameter
111 sys_getpgrp(struct getpgrp_args
*uap
)
113 struct proc
*p
= curproc
;
115 uap
->sysmsg_result
= p
->p_pgrp
->pg_id
;
120 * Get an arbitrary pid's process group id
123 sys_getpgid(struct getpgid_args
*uap
)
125 struct proc
*p
= curproc
;
132 if ((pt
= pfind(uap
->pid
)) == 0)
135 uap
->sysmsg_result
= pt
->p_pgrp
->pg_id
;
140 * Get an arbitrary pid's session id.
143 sys_getsid(struct getsid_args
*uap
)
145 struct proc
*p
= curproc
;
152 if ((pt
= pfind(uap
->pid
)) == 0)
155 uap
->sysmsg_result
= pt
->p_session
->s_sid
;
165 sys_getuid(struct getuid_args
*uap
)
167 struct proc
*p
= curproc
;
169 uap
->sysmsg_fds
[0] = p
->p_ucred
->cr_ruid
;
170 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
171 uap
->sysmsg_fds
[1] = p
->p_ucred
->cr_uid
;
177 * geteuid() - MP SAFE
181 sys_geteuid(struct geteuid_args
*uap
)
183 struct proc
*p
= curproc
;
185 uap
->sysmsg_result
= p
->p_ucred
->cr_uid
;
194 sys_getgid(struct getgid_args
*uap
)
196 struct proc
*p
= curproc
;
198 uap
->sysmsg_fds
[0] = p
->p_ucred
->cr_rgid
;
199 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
200 uap
->sysmsg_fds
[1] = p
->p_ucred
->cr_groups
[0];
206 * Get effective group ID. The "egid" is groups[0], and could be obtained
207 * via getgroups. This syscall exists because it is somewhat painful to do
208 * correctly in a library function.
214 sys_getegid(struct getegid_args
*uap
)
216 struct proc
*p
= curproc
;
218 uap
->sysmsg_result
= p
->p_ucred
->cr_groups
[0];
223 sys_getgroups(struct getgroups_args
*uap
)
225 struct proc
*p
= curproc
;
230 if (p
== NULL
) /* API enforcement */
234 if ((ngrp
= uap
->gidsetsize
) == 0) {
235 uap
->sysmsg_result
= cr
->cr_ngroups
;
238 if (ngrp
< cr
->cr_ngroups
)
240 ngrp
= cr
->cr_ngroups
;
241 if ((error
= copyout((caddr_t
)cr
->cr_groups
,
242 (caddr_t
)uap
->gidset
, ngrp
* sizeof(gid_t
))))
244 uap
->sysmsg_result
= ngrp
;
250 sys_setsid(struct setsid_args
*uap
)
252 struct proc
*p
= curproc
;
254 if (p
->p_pgid
== p
->p_pid
|| pgfind(p
->p_pid
)) {
257 (void)enterpgrp(p
, p
->p_pid
, 1);
258 uap
->sysmsg_result
= p
->p_pid
;
264 * set process group (setpgid/old setpgrp)
266 * caller does setpgid(targpid, targpgid)
268 * pid must be caller or child of caller (ESRCH)
270 * pid must be in same session (EPERM)
271 * pid can't have done an exec (EACCES)
273 * there must exist some pid in same session having pgid (EPERM)
274 * pid must not be session leader (EPERM)
278 sys_setpgid(struct setpgid_args
*uap
)
280 struct proc
*curp
= curproc
;
281 struct proc
*targp
; /* target process */
282 struct pgrp
*pgrp
; /* target pgrp */
286 if (uap
->pid
!= 0 && uap
->pid
!= curp
->p_pid
) {
287 if ((targp
= pfind(uap
->pid
)) == 0 || !inferior(targp
))
289 if (targp
->p_pgrp
== NULL
|| targp
->p_session
!= curp
->p_session
)
291 if (targp
->p_flag
& P_EXEC
)
295 if (SESS_LEADER(targp
))
298 uap
->pgid
= targp
->p_pid
;
299 else if (uap
->pgid
!= targp
->p_pid
)
300 if ((pgrp
= pgfind(uap
->pgid
)) == 0 ||
301 pgrp
->pg_session
!= curp
->p_session
)
303 return (enterpgrp(targp
, uap
->pgid
, 0));
307 * Use the clause in B.4.2.2 that allows setuid/setgid to be 4.2/4.3BSD
308 * compatible. It says that setting the uid/gid to euid/egid is a special
309 * case of "appropriate privilege". Once the rules are expanded out, this
310 * basically means that setuid(nnn) sets all three id's, in all permitted
311 * cases unless _POSIX_SAVED_IDS is enabled. In that case, setuid(getuid())
312 * does not set the saved id - this is dangerous for traditional BSD
313 * programs. For this reason, we *really* do not want to set
314 * _POSIX_SAVED_IDS and do not want to clear POSIX_APPENDIX_B_4_2_2.
316 #define POSIX_APPENDIX_B_4_2_2
320 sys_setuid(struct setuid_args
*uap
)
322 struct proc
*p
= curproc
;
327 if (p
== NULL
) /* API enforcement */
332 * See if we have "permission" by POSIX 1003.1 rules.
334 * Note that setuid(geteuid()) is a special case of
335 * "appropriate privileges" in appendix B.4.2.2. We need
336 * to use this clause to be compatible with traditional BSD
337 * semantics. Basically, it means that "setuid(xx)" sets all
338 * three id's (assuming you have privs).
340 * Notes on the logic. We do things in three steps.
341 * 1: We determine if the euid is going to change, and do EPERM
342 * right away. We unconditionally change the euid later if this
343 * test is satisfied, simplifying that part of the logic.
344 * 2: We determine if the real and/or saved uid's are going to
345 * change. Determined by compile options.
346 * 3: Change euid last. (after tests in #2 for "appropriate privs")
349 if (uid
!= cr
->cr_ruid
&& /* allow setuid(getuid()) */
350 #ifdef _POSIX_SAVED_IDS
351 uid
!= crc
->cr_svuid
&& /* allow setuid(saved gid) */
353 #ifdef POSIX_APPENDIX_B_4_2_2 /* Use BSD-compat clause from B.4.2.2 */
354 uid
!= cr
->cr_uid
&& /* allow setuid(geteuid()) */
356 (error
= priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
)))
359 #ifdef _POSIX_SAVED_IDS
361 * Do we have "appropriate privileges" (are we root or uid == euid)
362 * If so, we are changing the real uid and/or saved uid.
365 #ifdef POSIX_APPENDIX_B_4_2_2 /* Use the clause from B.4.2.2 */
368 priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
) == 0) /* we are using privs */
372 * Set the real uid and transfer proc count to new user.
374 if (uid
!= cr
->cr_ruid
) {
375 cr
= change_ruid(uid
);
381 * XXX always set saved uid even if not _POSIX_SAVED_IDS, as
382 * the security of seteuid() depends on it. B.4.2.2 says it
383 * is important that we should do this.
385 if (cr
->cr_svuid
!= uid
) {
386 cr
= cratom(&p
->p_ucred
);
393 * In all permitted cases, we are changing the euid.
394 * Copy credentials so other references do not see our changes.
396 if (cr
->cr_uid
!= uid
) {
405 sys_seteuid(struct seteuid_args
*uap
)
407 struct proc
*p
= curproc
;
412 if (p
== NULL
) /* API enforcement */
417 if (euid
!= cr
->cr_ruid
&& /* allow seteuid(getuid()) */
418 euid
!= cr
->cr_svuid
&& /* allow seteuid(saved uid) */
419 (error
= priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
)))
422 * Everything's okay, do it. Copy credentials so other references do
423 * not see our changes.
425 if (cr
->cr_uid
!= euid
) {
434 sys_setgid(struct setgid_args
*uap
)
436 struct proc
*p
= curproc
;
441 if (p
== NULL
) /* API enforcement */
446 * See if we have "permission" by POSIX 1003.1 rules.
448 * Note that setgid(getegid()) is a special case of
449 * "appropriate privileges" in appendix B.4.2.2. We need
450 * to use this clause to be compatible with traditional BSD
451 * semantics. Basically, it means that "setgid(xx)" sets all
452 * three id's (assuming you have privs).
454 * For notes on the logic here, see setuid() above.
457 if (gid
!= cr
->cr_rgid
&& /* allow setgid(getgid()) */
458 #ifdef _POSIX_SAVED_IDS
459 gid
!= cr
->cr_svgid
&& /* allow setgid(saved gid) */
461 #ifdef POSIX_APPENDIX_B_4_2_2 /* Use BSD-compat clause from B.4.2.2 */
462 gid
!= cr
->cr_groups
[0] && /* allow setgid(getegid()) */
464 (error
= priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
)))
467 #ifdef _POSIX_SAVED_IDS
469 * Do we have "appropriate privileges" (are we root or gid == egid)
470 * If so, we are changing the real uid and saved gid.
473 #ifdef POSIX_APPENDIX_B_4_2_2 /* use the clause from B.4.2.2 */
474 gid
== cr
->cr_groups
[0] ||
476 priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
) == 0) /* we are using privs */
482 if (cr
->cr_rgid
!= gid
) {
483 cr
= cratom(&p
->p_ucred
);
490 * XXX always set saved gid even if not _POSIX_SAVED_IDS, as
491 * the security of setegid() depends on it. B.4.2.2 says it
492 * is important that we should do this.
494 if (cr
->cr_svgid
!= gid
) {
495 cr
= cratom(&p
->p_ucred
);
501 * In all cases permitted cases, we are changing the egid.
502 * Copy credentials so other references do not see our changes.
504 if (cr
->cr_groups
[0] != gid
) {
505 cr
= cratom(&p
->p_ucred
);
506 cr
->cr_groups
[0] = gid
;
514 sys_setegid(struct setegid_args
*uap
)
516 struct proc
*p
= curproc
;
521 if (p
== NULL
) /* API enforcement */
526 if (egid
!= cr
->cr_rgid
&& /* allow setegid(getgid()) */
527 egid
!= cr
->cr_svgid
&& /* allow setegid(saved gid) */
528 (error
= priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
)))
530 if (cr
->cr_groups
[0] != egid
) {
531 cr
= cratom(&p
->p_ucred
);
532 cr
->cr_groups
[0] = egid
;
540 sys_setgroups(struct setgroups_args
*uap
)
542 struct proc
*p
= curproc
;
547 if (p
== NULL
) /* API enforcement */
551 if ((error
= priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
)))
553 ngrp
= uap
->gidsetsize
;
557 * XXX A little bit lazy here. We could test if anything has
558 * changed before cratom() and setting P_SUGID.
560 cr
= cratom(&p
->p_ucred
);
563 * setgroups(0, NULL) is a legitimate way of clearing the
564 * groups vector on non-BSD systems (which generally do not
565 * have the egid in the groups[0]). We risk security holes
566 * when running non-BSD software if we do not do the same.
570 if ((error
= copyin((caddr_t
)uap
->gidset
,
571 (caddr_t
)cr
->cr_groups
, ngrp
* sizeof(gid_t
))))
573 cr
->cr_ngroups
= ngrp
;
581 sys_setreuid(struct setreuid_args
*uap
)
583 struct proc
*p
= curproc
;
588 if (p
== NULL
) /* API enforcement */
594 if (((ruid
!= (uid_t
)-1 && ruid
!= cr
->cr_ruid
&& ruid
!= cr
->cr_svuid
) ||
595 (euid
!= (uid_t
)-1 && euid
!= cr
->cr_uid
&&
596 euid
!= cr
->cr_ruid
&& euid
!= cr
->cr_svuid
)) &&
597 (error
= priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
)) != 0)
600 if (euid
!= (uid_t
)-1 && cr
->cr_uid
!= euid
) {
601 cr
= change_euid(euid
);
604 if (ruid
!= (uid_t
)-1 && cr
->cr_ruid
!= ruid
) {
605 cr
= change_ruid(ruid
);
608 if ((ruid
!= (uid_t
)-1 || cr
->cr_uid
!= cr
->cr_ruid
) &&
609 cr
->cr_svuid
!= cr
->cr_uid
) {
610 cr
= cratom(&p
->p_ucred
);
611 cr
->cr_svuid
= cr
->cr_uid
;
619 sys_setregid(struct setregid_args
*uap
)
621 struct proc
*p
= curproc
;
626 if (p
== NULL
) /* API enforcement */
632 if (((rgid
!= (gid_t
)-1 && rgid
!= cr
->cr_rgid
&& rgid
!= cr
->cr_svgid
) ||
633 (egid
!= (gid_t
)-1 && egid
!= cr
->cr_groups
[0] &&
634 egid
!= cr
->cr_rgid
&& egid
!= cr
->cr_svgid
)) &&
635 (error
= priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
)) != 0)
638 if (egid
!= (gid_t
)-1 && cr
->cr_groups
[0] != egid
) {
639 cr
= cratom(&p
->p_ucred
);
640 cr
->cr_groups
[0] = egid
;
643 if (rgid
!= (gid_t
)-1 && cr
->cr_rgid
!= rgid
) {
644 cr
= cratom(&p
->p_ucred
);
648 if ((rgid
!= (gid_t
)-1 || cr
->cr_groups
[0] != cr
->cr_rgid
) &&
649 cr
->cr_svgid
!= cr
->cr_groups
[0]) {
650 cr
= cratom(&p
->p_ucred
);
651 cr
->cr_svgid
= cr
->cr_groups
[0];
658 * setresuid(ruid, euid, suid) is like setreuid except control over the
659 * saved uid is explicit.
664 sys_setresuid(struct setresuid_args
*uap
)
666 struct proc
*p
= curproc
;
668 uid_t ruid
, euid
, suid
;
675 if (((ruid
!= (uid_t
)-1 && ruid
!= cr
->cr_ruid
&& ruid
!= cr
->cr_svuid
&&
676 ruid
!= cr
->cr_uid
) ||
677 (euid
!= (uid_t
)-1 && euid
!= cr
->cr_ruid
&& euid
!= cr
->cr_svuid
&&
678 euid
!= cr
->cr_uid
) ||
679 (suid
!= (uid_t
)-1 && suid
!= cr
->cr_ruid
&& suid
!= cr
->cr_svuid
&&
680 suid
!= cr
->cr_uid
)) &&
681 (error
= priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
)) != 0)
683 if (euid
!= (uid_t
)-1 && cr
->cr_uid
!= euid
) {
684 cr
= change_euid(euid
);
687 if (ruid
!= (uid_t
)-1 && cr
->cr_ruid
!= ruid
) {
688 cr
= change_ruid(ruid
);
691 if (suid
!= (uid_t
)-1 && cr
->cr_svuid
!= suid
) {
692 cr
= cratom(&p
->p_ucred
);
700 * setresgid(rgid, egid, sgid) is like setregid except control over the
701 * saved gid is explicit.
706 sys_setresgid(struct setresgid_args
*uap
)
708 struct proc
*p
= curproc
;
710 gid_t rgid
, egid
, sgid
;
717 if (((rgid
!= (gid_t
)-1 && rgid
!= cr
->cr_rgid
&& rgid
!= cr
->cr_svgid
&&
718 rgid
!= cr
->cr_groups
[0]) ||
719 (egid
!= (gid_t
)-1 && egid
!= cr
->cr_rgid
&& egid
!= cr
->cr_svgid
&&
720 egid
!= cr
->cr_groups
[0]) ||
721 (sgid
!= (gid_t
)-1 && sgid
!= cr
->cr_rgid
&& sgid
!= cr
->cr_svgid
&&
722 sgid
!= cr
->cr_groups
[0])) &&
723 (error
= priv_check_cred(cr
, PRIV_ROOT
, PRISON_ROOT
)) != 0)
726 if (egid
!= (gid_t
)-1 && cr
->cr_groups
[0] != egid
) {
727 cr
= cratom(&p
->p_ucred
);
728 cr
->cr_groups
[0] = egid
;
731 if (rgid
!= (gid_t
)-1 && cr
->cr_rgid
!= rgid
) {
732 cr
= cratom(&p
->p_ucred
);
736 if (sgid
!= (gid_t
)-1 && cr
->cr_svgid
!= sgid
) {
737 cr
= cratom(&p
->p_ucred
);
746 sys_getresuid(struct getresuid_args
*uap
)
748 struct proc
*p
= curproc
;
749 struct ucred
*cr
= p
->p_ucred
;
750 int error1
= 0, error2
= 0, error3
= 0;
753 error1
= copyout((caddr_t
)&cr
->cr_ruid
,
754 (caddr_t
)uap
->ruid
, sizeof(cr
->cr_ruid
));
756 error2
= copyout((caddr_t
)&cr
->cr_uid
,
757 (caddr_t
)uap
->euid
, sizeof(cr
->cr_uid
));
759 error3
= copyout((caddr_t
)&cr
->cr_svuid
,
760 (caddr_t
)uap
->suid
, sizeof(cr
->cr_svuid
));
761 return error1
? error1
: (error2
? error2
: error3
);
766 sys_getresgid(struct getresgid_args
*uap
)
768 struct proc
*p
= curproc
;
769 struct ucred
*cr
= p
->p_ucred
;
770 int error1
= 0, error2
= 0, error3
= 0;
773 error1
= copyout((caddr_t
)&cr
->cr_rgid
,
774 (caddr_t
)uap
->rgid
, sizeof(cr
->cr_rgid
));
776 error2
= copyout((caddr_t
)&cr
->cr_groups
[0],
777 (caddr_t
)uap
->egid
, sizeof(cr
->cr_groups
[0]));
779 error3
= copyout((caddr_t
)&cr
->cr_svgid
,
780 (caddr_t
)uap
->sgid
, sizeof(cr
->cr_svgid
));
781 return error1
? error1
: (error2
? error2
: error3
);
787 sys_issetugid(struct issetugid_args
*uap
)
789 struct proc
*p
= curproc
;
791 * Note: OpenBSD sets a P_SUGIDEXEC flag set at execve() time,
792 * we use P_SUGID because we consider changing the owners as
793 * "tainting" as well.
794 * This is significant for procs that start as root and "become"
795 * a user without an exec - programs cannot know *everything*
796 * that libc *might* have put in their data segment.
798 uap
->sysmsg_result
= (p
->p_flag
& P_SUGID
) ? 1 : 0;
803 * Check if gid is a member of the group set.
806 groupmember(gid_t gid
, struct ucred
*cred
)
811 egp
= &(cred
->cr_groups
[cred
->cr_ngroups
]);
812 for (gp
= cred
->cr_groups
; gp
< egp
; gp
++) {
820 * Test whether the specified credentials imply "super-user"
823 * Depreciated! Use priv_check() instead.
826 suser(struct thread
*td
)
828 return priv_check(td
, PRIV_ROOT
);
832 * Depreciated! Use priv_check_cred() instead.
835 suser_cred(struct ucred
*cred
, int flag
)
837 return priv_check_cred(cred
, PRIV_ROOT
, flag
);
841 * Test whether the specified credentials have the privilege
844 * A kernel thread without a process context is assumed to have
845 * the privilege in question. In situations where the caller always
846 * expect a cred to exist, the cred should be passed separately and
847 * priv_check_cred() should be used instead of priv_check().
849 * Returns 0 or error.
852 priv_check(struct thread
*td
, int priv
)
854 struct proc
*p
= td
->td_proc
;
857 return priv_check_cred(p
->p_ucred
, priv
, 0);
864 * Check a credential for privilege.
866 * A non-null credential is expected unless NULL_CRED_OKAY is set.
869 priv_check_cred(struct ucred
*cred
, int priv
, int flags
)
871 KASSERT(PRIV_VALID(priv
), ("priv_check_cred: invalid privilege"));
873 KASSERT(cred
!= NULL
|| flags
& NULL_CRED_OKAY
,
874 ("priv_check_cred: NULL cred!"));
877 if (flags
& NULL_CRED_OKAY
)
882 if (cred
->cr_uid
!= 0)
884 if (cred
->cr_prison
&& !(flags
& PRISON_ROOT
))
886 /* NOTE: accounting for suser access (p_acflag/ASU) removed */
891 * Return zero if p1 can fondle p2, return errno (EPERM/ESRCH) otherwise.
894 p_trespass(struct ucred
*cr1
, struct ucred
*cr2
)
898 if (!PRISON_CHECK(cr1
, cr2
))
900 if (cr1
->cr_ruid
== cr2
->cr_ruid
)
902 if (cr1
->cr_uid
== cr2
->cr_ruid
)
904 if (cr1
->cr_ruid
== cr2
->cr_uid
)
906 if (cr1
->cr_uid
== cr2
->cr_uid
)
908 if (priv_check_cred(cr1
, PRIV_ROOT
, PRISON_ROOT
) == 0)
917 _crinit(struct ucred
*cr
)
919 bzero(cr
, sizeof(*cr
));
921 spin_init(&cr
->cr_spin
);
928 crinit(struct ucred
*cr
)
934 * Allocate a zeroed cred structure.
943 MALLOC(cr
, struct ucred
*, sizeof(*cr
), M_CRED
, M_WAITOK
);
949 * Claim another reference to a ucred structure. Can be used with special
952 * It must be possible to call this routine with spinlocks held, meaning
953 * that this routine itself cannot obtain a spinlock.
958 crhold(struct ucred
*cr
)
960 if (cr
!= NOCRED
&& cr
!= FSCRED
)
961 atomic_add_int(&cr
->cr_ref
, 1);
966 * Drop a reference from the cred structure, free it if the reference count
969 * NOTE: because we used atomic_add_int() above, without a spinlock, we
970 * must also use atomic_subtract_int() below. A spinlock is required
971 * in crfree() to handle multiple callers racing the refcount to 0.
973 * MPALMOSTSAFE - acquires mplock on 1->0 transition of ref count
976 crfree(struct ucred
*cr
)
979 panic("Freeing already free credential! %p", cr
);
980 spin_lock_wr(&cr
->cr_spin
);
981 atomic_subtract_int(&cr
->cr_ref
, 1);
982 if (cr
->cr_ref
== 0) {
983 spin_unlock_wr(&cr
->cr_spin
);
985 * Some callers of crget(), such as nfs_statfs(),
986 * allocate a temporary credential, but don't
987 * allocate a uidinfo structure.
990 if (cr
->cr_uidinfo
!= NULL
) {
991 uidrop(cr
->cr_uidinfo
);
992 cr
->cr_uidinfo
= NULL
;
994 if (cr
->cr_ruidinfo
!= NULL
) {
995 uidrop(cr
->cr_ruidinfo
);
996 cr
->cr_ruidinfo
= NULL
;
1000 * Destroy empty prisons
1003 prison_free(cr
->cr_prison
);
1004 cr
->cr_prison
= NULL
; /* safety */
1006 FREE((caddr_t
)cr
, M_CRED
);
1009 spin_unlock_wr(&cr
->cr_spin
);
1014 * Atomize a cred structure so it can be modified without polluting
1015 * other references to it.
1018 cratom(struct ucred
**pcr
)
1020 struct ucred
*oldcr
;
1021 struct ucred
*newcr
;
1024 if (oldcr
->cr_ref
== 1)
1028 if (newcr
->cr_uidinfo
)
1029 uihold(newcr
->cr_uidinfo
);
1030 if (newcr
->cr_ruidinfo
)
1031 uihold(newcr
->cr_ruidinfo
);
1033 prison_hold(newcr
->cr_prison
);
1040 #if 0 /* no longer used but keep around for a little while */
1042 * Copy cred structure to a new one and free the old one.
1045 crcopy(struct ucred
*cr
)
1047 struct ucred
*newcr
;
1049 if (cr
->cr_ref
== 1)
1053 if (newcr
->cr_uidinfo
)
1054 uihold(newcr
->cr_uidinfo
);
1055 if (newcr
->cr_ruidinfo
)
1056 uihold(newcr
->cr_ruidinfo
);
1058 prison_hold(newcr
->cr_prison
);
1066 * Dup cred struct to a new held one.
1069 crdup(struct ucred
*cr
)
1071 struct ucred
*newcr
;
1075 if (newcr
->cr_uidinfo
)
1076 uihold(newcr
->cr_uidinfo
);
1077 if (newcr
->cr_ruidinfo
)
1078 uihold(newcr
->cr_ruidinfo
);
1080 prison_hold(newcr
->cr_prison
);
1086 * Fill in a struct xucred based on a struct ucred.
1089 cru2x(struct ucred
*cr
, struct xucred
*xcr
)
1092 bzero(xcr
, sizeof(*xcr
));
1093 xcr
->cr_version
= XUCRED_VERSION
;
1094 xcr
->cr_uid
= cr
->cr_uid
;
1095 xcr
->cr_ngroups
= cr
->cr_ngroups
;
1096 bcopy(cr
->cr_groups
, xcr
->cr_groups
, sizeof(cr
->cr_groups
));
1100 * Get login name, if available.
1104 sys_getlogin(struct getlogin_args
*uap
)
1106 struct proc
*p
= curproc
;
1108 if (uap
->namelen
> MAXLOGNAME
)
1109 uap
->namelen
= MAXLOGNAME
;
1110 return (copyout((caddr_t
) p
->p_pgrp
->pg_session
->s_login
,
1111 (caddr_t
) uap
->namebuf
, uap
->namelen
));
1119 sys_setlogin(struct setlogin_args
*uap
)
1121 struct proc
*p
= curproc
;
1123 char logintmp
[MAXLOGNAME
];
1125 KKASSERT(p
!= NULL
);
1126 if ((error
= priv_check_cred(p
->p_ucred
, PRIV_ROOT
, PRISON_ROOT
)))
1128 error
= copyinstr((caddr_t
) uap
->namebuf
, (caddr_t
) logintmp
,
1129 sizeof(logintmp
), (size_t *)0);
1130 if (error
== ENAMETOOLONG
)
1133 (void) memcpy(p
->p_pgrp
->pg_session
->s_login
, logintmp
,
1141 struct proc
*p
= curproc
;
1143 KKASSERT(p
!= NULL
);
1144 p
->p_flag
|= P_SUGID
;
1145 if (!(p
->p_pfsflags
& PF_ISUGID
))
1150 * Helper function to change the effective uid of a process
1153 change_euid(uid_t euid
)
1155 struct proc
*p
= curproc
;
1158 KKASSERT(p
!= NULL
);
1159 lf_count_adjust(p
, 0);
1160 cr
= cratom(&p
->p_ucred
);
1162 uireplace(&cr
->cr_uidinfo
, uifind(euid
));
1163 lf_count_adjust(p
, 1);
1168 * Helper function to change the real uid of a process
1170 * The per-uid process count for this process is transfered from
1171 * the old uid to the new uid.
1174 change_ruid(uid_t ruid
)
1176 struct proc
*p
= curproc
;
1179 KKASSERT(p
!= NULL
);
1181 cr
= cratom(&p
->p_ucred
);
1182 chgproccnt(cr
->cr_ruidinfo
, -1, 0);
1184 uireplace(&cr
->cr_ruidinfo
, uifind(ruid
));
1185 chgproccnt(cr
->cr_ruidinfo
, 1, 0);