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34 * @(#)kern_prot.c 8.6 (Berkeley) 1/21/94
35 * $FreeBSD: src/sys/kern/kern_prot.c,v 1.53.2.9 2002/03/09 05:20:26 dd Exp $
39 * System calls related to processes and protection
42 #include "opt_compat.h"
44 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/sysproto.h>
48 #include <sys/kernel.h>
52 #include <sys/malloc.h>
53 #include <sys/pioctl.h>
54 #include <sys/resourcevar.h>
56 #include <sys/lockf.h>
57 #include <sys/spinlock.h>
59 #include <sys/thread2.h>
60 #include <sys/spinlock2.h>
62 static MALLOC_DEFINE(M_CRED, "cred", "credentials");
65 sys_getpid(struct getpid_args *uap)
67 struct proc *p = curproc;
69 uap->sysmsg_fds[0] = p->p_pid;
70 #if defined(COMPAT_43)
71 lwkt_gettoken_shared(&p->p_token);
72 uap->sysmsg_fds[1] = p->p_pptr->p_pid;
73 lwkt_reltoken(&p->p_token);
79 sys_getppid(struct getppid_args *uap)
81 struct proc *p = curproc;
83 lwkt_gettoken_shared(&p->p_token);
84 uap->sysmsg_result = p->p_pptr->p_pid;
85 lwkt_reltoken(&p->p_token);
94 sys_lwp_gettid(struct lwp_gettid_args *uap)
96 struct lwp *lp = curthread->td_lwp;
97 uap->sysmsg_result = lp->lwp_tid;
102 * Get process group ID; note that POSIX getpgrp takes no parameter
107 sys_getpgrp(struct getpgrp_args *uap)
109 struct proc *p = curproc;
111 lwkt_gettoken_shared(&p->p_token);
112 uap->sysmsg_result = p->p_pgrp->pg_id;
113 lwkt_reltoken(&p->p_token);
119 * Get an arbitrary pid's process group id
122 sys_getpgid(struct getpgid_args *uap)
124 struct proc *p = curproc;
134 pt = pfind(uap->pid);
138 /* XXX MPSAFE on pgrp? */
140 lwkt_gettoken_shared(&pt->p_token);
141 uap->sysmsg_result = pt->p_pgrp->pg_id;
142 lwkt_reltoken(&pt->p_token);
150 * Get an arbitrary pid's session id.
153 sys_getsid(struct getsid_args *uap)
155 struct proc *p = curproc;
165 pt = pfind(uap->pid);
170 uap->sysmsg_result = pt->p_session->s_sid;
183 sys_getuid(struct getuid_args *uap)
185 struct ucred *cred = curthread->td_ucred;
187 uap->sysmsg_fds[0] = cred->cr_ruid;
188 #if defined(COMPAT_43)
189 uap->sysmsg_fds[1] = cred->cr_uid;
200 sys_geteuid(struct geteuid_args *uap)
202 struct ucred *cred = curthread->td_ucred;
204 uap->sysmsg_result = cred->cr_uid;
214 sys_getgid(struct getgid_args *uap)
216 struct ucred *cred = curthread->td_ucred;
218 uap->sysmsg_fds[0] = cred->cr_rgid;
219 #if defined(COMPAT_43)
220 uap->sysmsg_fds[1] = cred->cr_groups[0];
226 * Get effective group ID. The "egid" is groups[0], and could be obtained
227 * via getgroups. This syscall exists because it is somewhat painful to do
228 * correctly in a library function.
233 sys_getegid(struct getegid_args *uap)
235 struct ucred *cred = curthread->td_ucred;
237 uap->sysmsg_result = cred->cr_groups[0];
245 sys_getgroups(struct getgroups_args *uap)
251 cr = curthread->td_ucred;
252 if ((ngrp = uap->gidsetsize) == 0) {
253 uap->sysmsg_result = cr->cr_ngroups;
256 if (ngrp < cr->cr_ngroups)
258 ngrp = cr->cr_ngroups;
259 error = copyout((caddr_t)cr->cr_groups,
260 (caddr_t)uap->gidset, ngrp * sizeof(gid_t));
262 uap->sysmsg_result = ngrp;
267 sys_setsid(struct setsid_args *uap)
269 struct proc *p = curproc;
270 struct pgrp *pg = NULL;
273 lwkt_gettoken(&p->p_token);
274 if (p->p_pgid == p->p_pid || (pg = pgfind(p->p_pid)) != NULL) {
279 enterpgrp(p, p->p_pid, 1);
280 uap->sysmsg_result = p->p_pid;
283 lwkt_reltoken(&p->p_token);
288 * set process group (setpgid/old setpgrp)
290 * caller does setpgid(targpid, targpgid)
292 * pid must be caller or child of caller (ESRCH)
294 * pid must be in same session (EPERM)
295 * pid can't have done an exec (EACCES)
297 * there must exist some pid in same session having pgid (EPERM)
298 * pid must not be session leader (EPERM)
301 sys_setpgid(struct setpgid_args *uap)
303 struct proc *curp = curproc;
304 struct proc *targp; /* target process */
305 struct pgrp *pgrp = NULL; /* target pgrp */
311 if (uap->pid != 0 && uap->pid != curp->p_pid) {
312 if ((targp = pfind(uap->pid)) == NULL || !inferior(targp)) {
319 lwkt_gettoken(&targp->p_token);
320 /* targp now referenced and its token is held */
322 if (targp->p_pgrp == NULL ||
323 targp->p_session != curp->p_session) {
327 if (targp->p_flags & P_EXEC) {
334 lwkt_gettoken(&targp->p_token);
336 if (SESS_LEADER(targp)) {
340 if (uap->pgid == 0) {
341 uap->pgid = targp->p_pid;
342 } else if (uap->pgid != targp->p_pid) {
343 if ((pgrp = pgfind(uap->pgid)) == NULL ||
344 pgrp->pg_session != curp->p_session) {
349 error = enterpgrp(targp, uap->pgid, 0);
354 lwkt_reltoken(&targp->p_token);
361 * Use the clause in B.4.2.2 that allows setuid/setgid to be 4.2/4.3BSD
362 * compatible. It says that setting the uid/gid to euid/egid is a special
363 * case of "appropriate privilege". Once the rules are expanded out, this
364 * basically means that setuid(nnn) sets all three id's, in all permitted
365 * cases unless _POSIX_SAVED_IDS is enabled. In that case, setuid(getuid())
366 * does not set the saved id - this is dangerous for traditional BSD
367 * programs. For this reason, we *really* do not want to set
368 * _POSIX_SAVED_IDS and do not want to clear POSIX_APPENDIX_B_4_2_2.
370 #define POSIX_APPENDIX_B_4_2_2
373 sys_setuid(struct setuid_args *uap)
375 struct proc *p = curproc;
380 lwkt_gettoken(&proc_token);
384 * See if we have "permission" by POSIX 1003.1 rules.
386 * Note that setuid(geteuid()) is a special case of
387 * "appropriate privileges" in appendix B.4.2.2. We need
388 * to use this clause to be compatible with traditional BSD
389 * semantics. Basically, it means that "setuid(xx)" sets all
390 * three id's (assuming you have privs).
392 * Notes on the logic. We do things in three steps.
393 * 1: We determine if the euid is going to change, and do EPERM
394 * right away. We unconditionally change the euid later if this
395 * test is satisfied, simplifying that part of the logic.
396 * 2: We determine if the real and/or saved uid's are going to
397 * change. Determined by compile options.
398 * 3: Change euid last. (after tests in #2 for "appropriate privs")
401 if (uid != cr->cr_ruid && /* allow setuid(getuid()) */
402 #ifdef _POSIX_SAVED_IDS
403 uid != crc->cr_svuid && /* allow setuid(saved gid) */
405 #ifdef POSIX_APPENDIX_B_4_2_2 /* Use BSD-compat clause from B.4.2.2 */
406 uid != cr->cr_uid && /* allow setuid(geteuid()) */
408 (error = priv_check_cred(cr, PRIV_CRED_SETUID, 0)))
411 #ifdef _POSIX_SAVED_IDS
413 * Do we have "appropriate privileges" (are we root or uid == euid)
414 * If so, we are changing the real uid and/or saved uid.
417 #ifdef POSIX_APPENDIX_B_4_2_2 /* Use the clause from B.4.2.2 */
420 priv_check_cred(cr, PRIV_CRED_SETUID, 0) == 0) /* we are using privs */
424 * Set the real uid and transfer proc count to new user.
426 if (uid != cr->cr_ruid) {
427 cr = change_ruid(uid);
433 * XXX always set saved uid even if not _POSIX_SAVED_IDS, as
434 * the security of seteuid() depends on it. B.4.2.2 says it
435 * is important that we should do this.
437 if (cr->cr_svuid != uid) {
438 cr = cratom(&p->p_ucred);
445 * In all permitted cases, we are changing the euid.
446 * Copy credentials so other references do not see our changes.
448 if (cr->cr_uid != uid) {
454 lwkt_reltoken(&proc_token);
459 sys_seteuid(struct seteuid_args *uap)
461 struct proc *p = curproc;
466 lwkt_gettoken(&proc_token);
469 if (euid != cr->cr_ruid && /* allow seteuid(getuid()) */
470 euid != cr->cr_svuid && /* allow seteuid(saved uid) */
471 (error = priv_check_cred(cr, PRIV_CRED_SETEUID, 0))) {
472 lwkt_reltoken(&proc_token);
477 * Everything's okay, do it. Copy credentials so other references do
478 * not see our changes.
480 if (cr->cr_uid != euid) {
484 lwkt_reltoken(&proc_token);
489 sys_setgid(struct setgid_args *uap)
491 struct proc *p = curproc;
496 lwkt_gettoken(&proc_token);
500 * See if we have "permission" by POSIX 1003.1 rules.
502 * Note that setgid(getegid()) is a special case of
503 * "appropriate privileges" in appendix B.4.2.2. We need
504 * to use this clause to be compatible with traditional BSD
505 * semantics. Basically, it means that "setgid(xx)" sets all
506 * three id's (assuming you have privs).
508 * For notes on the logic here, see setuid() above.
511 if (gid != cr->cr_rgid && /* allow setgid(getgid()) */
512 #ifdef _POSIX_SAVED_IDS
513 gid != cr->cr_svgid && /* allow setgid(saved gid) */
515 #ifdef POSIX_APPENDIX_B_4_2_2 /* Use BSD-compat clause from B.4.2.2 */
516 gid != cr->cr_groups[0] && /* allow setgid(getegid()) */
518 (error = priv_check_cred(cr, PRIV_CRED_SETGID, 0))) {
522 #ifdef _POSIX_SAVED_IDS
524 * Do we have "appropriate privileges" (are we root or gid == egid)
525 * If so, we are changing the real uid and saved gid.
528 #ifdef POSIX_APPENDIX_B_4_2_2 /* use the clause from B.4.2.2 */
529 gid == cr->cr_groups[0] ||
531 priv_check_cred(cr, PRIV_CRED_SETGID, 0) == 0) /* we are using privs */
537 if (cr->cr_rgid != gid) {
538 cr = cratom(&p->p_ucred);
545 * XXX always set saved gid even if not _POSIX_SAVED_IDS, as
546 * the security of setegid() depends on it. B.4.2.2 says it
547 * is important that we should do this.
549 if (cr->cr_svgid != gid) {
550 cr = cratom(&p->p_ucred);
556 * In all cases permitted cases, we are changing the egid.
557 * Copy credentials so other references do not see our changes.
559 if (cr->cr_groups[0] != gid) {
560 cr = cratom(&p->p_ucred);
561 cr->cr_groups[0] = gid;
566 lwkt_reltoken(&proc_token);
571 sys_setegid(struct setegid_args *uap)
573 struct proc *p = curproc;
578 lwkt_gettoken(&proc_token);
581 if (egid != cr->cr_rgid && /* allow setegid(getgid()) */
582 egid != cr->cr_svgid && /* allow setegid(saved gid) */
583 (error = priv_check_cred(cr, PRIV_CRED_SETEGID, 0))) {
586 if (cr->cr_groups[0] != egid) {
587 cr = cratom(&p->p_ucred);
588 cr->cr_groups[0] = egid;
593 lwkt_reltoken(&proc_token);
598 sys_setgroups(struct setgroups_args *uap)
600 struct proc *p = curproc;
605 lwkt_gettoken(&proc_token);
608 if ((error = priv_check_cred(cr, PRIV_CRED_SETGROUPS, 0)))
610 ngrp = uap->gidsetsize;
611 if (ngrp > NGROUPS) {
616 * XXX A little bit lazy here. We could test if anything has
617 * changed before cratom() and setting P_SUGID.
619 cr = cratom(&p->p_ucred);
622 * setgroups(0, NULL) is a legitimate way of clearing the
623 * groups vector on non-BSD systems (which generally do not
624 * have the egid in the groups[0]). We risk security holes
625 * when running non-BSD software if we do not do the same.
629 error = copyin(uap->gidset, cr->cr_groups,
630 ngrp * sizeof(gid_t));
633 cr->cr_ngroups = ngrp;
638 lwkt_reltoken(&proc_token);
643 sys_setreuid(struct setreuid_args *uap)
645 struct proc *p = curproc;
650 lwkt_gettoken(&proc_token);
655 if (((ruid != (uid_t)-1 && ruid != cr->cr_ruid && ruid != cr->cr_svuid) ||
656 (euid != (uid_t)-1 && euid != cr->cr_uid &&
657 euid != cr->cr_ruid && euid != cr->cr_svuid)) &&
658 (error = priv_check_cred(cr, PRIV_CRED_SETREUID, 0)) != 0) {
662 if (euid != (uid_t)-1 && cr->cr_uid != euid) {
663 cr = change_euid(euid);
666 if (ruid != (uid_t)-1 && cr->cr_ruid != ruid) {
667 cr = change_ruid(ruid);
670 if ((ruid != (uid_t)-1 || cr->cr_uid != cr->cr_ruid) &&
671 cr->cr_svuid != cr->cr_uid) {
672 cr = cratom(&p->p_ucred);
673 cr->cr_svuid = cr->cr_uid;
678 lwkt_reltoken(&proc_token);
683 sys_setregid(struct setregid_args *uap)
685 struct proc *p = curproc;
690 lwkt_gettoken(&proc_token);
695 if (((rgid != (gid_t)-1 && rgid != cr->cr_rgid && rgid != cr->cr_svgid) ||
696 (egid != (gid_t)-1 && egid != cr->cr_groups[0] &&
697 egid != cr->cr_rgid && egid != cr->cr_svgid)) &&
698 (error = priv_check_cred(cr, PRIV_CRED_SETREGID, 0)) != 0) {
702 if (egid != (gid_t)-1 && cr->cr_groups[0] != egid) {
703 cr = cratom(&p->p_ucred);
704 cr->cr_groups[0] = egid;
707 if (rgid != (gid_t)-1 && cr->cr_rgid != rgid) {
708 cr = cratom(&p->p_ucred);
712 if ((rgid != (gid_t)-1 || cr->cr_groups[0] != cr->cr_rgid) &&
713 cr->cr_svgid != cr->cr_groups[0]) {
714 cr = cratom(&p->p_ucred);
715 cr->cr_svgid = cr->cr_groups[0];
720 lwkt_reltoken(&proc_token);
725 * setresuid(ruid, euid, suid) is like setreuid except control over the
726 * saved uid is explicit.
729 sys_setresuid(struct setresuid_args *uap)
731 struct proc *p = curproc;
733 uid_t ruid, euid, suid;
736 lwkt_gettoken(&proc_token);
742 if (((ruid != (uid_t)-1 && ruid != cr->cr_ruid && ruid != cr->cr_svuid &&
743 ruid != cr->cr_uid) ||
744 (euid != (uid_t)-1 && euid != cr->cr_ruid && euid != cr->cr_svuid &&
745 euid != cr->cr_uid) ||
746 (suid != (uid_t)-1 && suid != cr->cr_ruid && suid != cr->cr_svuid &&
747 suid != cr->cr_uid)) &&
748 (error = priv_check_cred(cr, PRIV_CRED_SETRESUID, 0)) != 0) {
751 if (euid != (uid_t)-1 && cr->cr_uid != euid) {
752 cr = change_euid(euid);
755 if (ruid != (uid_t)-1 && cr->cr_ruid != ruid) {
756 cr = change_ruid(ruid);
759 if (suid != (uid_t)-1 && cr->cr_svuid != suid) {
760 cr = cratom(&p->p_ucred);
766 lwkt_reltoken(&proc_token);
771 * setresgid(rgid, egid, sgid) is like setregid except control over the
772 * saved gid is explicit.
775 sys_setresgid(struct setresgid_args *uap)
777 struct proc *p = curproc;
779 gid_t rgid, egid, sgid;
782 lwkt_gettoken(&proc_token);
787 if (((rgid != (gid_t)-1 && rgid != cr->cr_rgid && rgid != cr->cr_svgid &&
788 rgid != cr->cr_groups[0]) ||
789 (egid != (gid_t)-1 && egid != cr->cr_rgid && egid != cr->cr_svgid &&
790 egid != cr->cr_groups[0]) ||
791 (sgid != (gid_t)-1 && sgid != cr->cr_rgid && sgid != cr->cr_svgid &&
792 sgid != cr->cr_groups[0])) &&
793 (error = priv_check_cred(cr, PRIV_CRED_SETRESGID, 0)) != 0) {
797 if (egid != (gid_t)-1 && cr->cr_groups[0] != egid) {
798 cr = cratom(&p->p_ucred);
799 cr->cr_groups[0] = egid;
802 if (rgid != (gid_t)-1 && cr->cr_rgid != rgid) {
803 cr = cratom(&p->p_ucred);
807 if (sgid != (gid_t)-1 && cr->cr_svgid != sgid) {
808 cr = cratom(&p->p_ucred);
814 lwkt_reltoken(&proc_token);
819 sys_getresuid(struct getresuid_args *uap)
821 struct proc *p = curproc;
823 int error1 = 0, error2 = 0, error3 = 0;
826 * copyout's can fault synchronously so we cannot use a shared
829 lwkt_gettoken_shared(&p->p_token);
830 cr = crhold(p->p_ucred);
831 lwkt_reltoken(&p->p_token);
833 error1 = copyout((caddr_t)&cr->cr_ruid,
834 (caddr_t)uap->ruid, sizeof(cr->cr_ruid));
836 error2 = copyout((caddr_t)&cr->cr_uid,
837 (caddr_t)uap->euid, sizeof(cr->cr_uid));
839 error3 = copyout((caddr_t)&cr->cr_svuid,
840 (caddr_t)uap->suid, sizeof(cr->cr_svuid));
842 return error1 ? error1 : (error2 ? error2 : error3);
849 sys_getresgid(struct getresgid_args *uap)
852 int error1 = 0, error2 = 0, error3 = 0;
854 cr = curthread->td_ucred;
856 error1 = copyout(&cr->cr_rgid, uap->rgid,
857 sizeof(cr->cr_rgid));
859 error2 = copyout(&cr->cr_groups[0], uap->egid,
860 sizeof(cr->cr_groups[0]));
862 error3 = copyout(&cr->cr_svgid, uap->sgid,
863 sizeof(cr->cr_svgid));
864 return error1 ? error1 : (error2 ? error2 : error3);
869 * NOTE: OpenBSD sets a P_SUGIDEXEC flag set at execve() time,
870 * we use P_SUGID because we consider changing the owners as
871 * "tainting" as well.
872 * This is significant for procs that start as root and "become"
873 * a user without an exec - programs cannot know *everything*
874 * that libc *might* have put in their data segment.
879 sys_issetugid(struct issetugid_args *uap)
881 uap->sysmsg_result = (curproc->p_flags & P_SUGID) ? 1 : 0;
886 * Check if gid is a member of the group set.
889 groupmember(gid_t gid, struct ucred *cred)
894 egp = &(cred->cr_groups[cred->cr_ngroups]);
895 for (gp = cred->cr_groups; gp < egp; gp++) {
903 * Test whether the specified credentials have the privilege
906 * A kernel thread without a process context is assumed to have
907 * the privilege in question. In situations where the caller always
908 * expect a cred to exist, the cred should be passed separately and
909 * priv_check_cred() should be used instead of priv_check().
911 * Returns 0 or error.
916 priv_check(struct thread *td, int priv)
918 if (td->td_lwp != NULL)
919 return priv_check_cred(td->td_ucred, priv, 0);
924 * Check a credential for privilege.
926 * A non-null credential is expected unless NULL_CRED_OKAY is set.
931 priv_check_cred(struct ucred *cred, int priv, int flags)
935 KASSERT(PRIV_VALID(priv), ("priv_check_cred: invalid privilege"));
937 KASSERT(cred != NULL || flags & NULL_CRED_OKAY,
938 ("priv_check_cred: NULL cred!"));
941 if (flags & NULL_CRED_OKAY)
946 if (cred->cr_uid != 0)
949 error = prison_priv_check(cred, priv);
953 /* NOTE: accounting for suser access (p_acflag/ASU) removed */
958 * Return zero if p1 can fondle p2, return errno (EPERM/ESRCH) otherwise.
961 p_trespass(struct ucred *cr1, struct ucred *cr2)
965 if (!PRISON_CHECK(cr1, cr2))
967 if (cr1->cr_ruid == cr2->cr_ruid)
969 if (cr1->cr_uid == cr2->cr_ruid)
971 if (cr1->cr_ruid == cr2->cr_uid)
973 if (cr1->cr_uid == cr2->cr_uid)
975 if (priv_check_cred(cr1, PRIV_PROC_TRESPASS, 0) == 0)
984 _crinit(struct ucred *cr)
993 crinit(struct ucred *cr)
995 bzero(cr, sizeof(*cr));
1000 * Allocate a zeroed cred structure.
1009 cr = kmalloc(sizeof(*cr), M_CRED, M_WAITOK|M_ZERO);
1015 * Claim another reference to a ucred structure. Can be used with special
1018 * It must be possible to call this routine with spinlocks held, meaning
1019 * that this routine itself cannot obtain a spinlock.
1024 crhold(struct ucred *cr)
1026 if (cr != NOCRED && cr != FSCRED)
1027 atomic_add_int(&cr->cr_ref, 1);
1032 * Drop a reference from the cred structure, free it if the reference count
1035 * NOTE: because we used atomic_add_int() above, without a spinlock, we
1036 * must also use atomic_subtract_int() below. A spinlock is required
1037 * in crfree() to handle multiple callers racing the refcount to 0.
1042 crfree(struct ucred *cr)
1044 if (cr->cr_ref <= 0)
1045 panic("Freeing already free credential! %p", cr);
1046 if (atomic_fetchadd_int(&cr->cr_ref, -1) == 1) {
1048 * Some callers of crget(), such as nfs_statfs(),
1049 * allocate a temporary credential, but don't
1050 * allocate a uidinfo structure.
1052 if (cr->cr_uidinfo != NULL) {
1053 uidrop(cr->cr_uidinfo);
1054 cr->cr_uidinfo = NULL;
1056 if (cr->cr_ruidinfo != NULL) {
1057 uidrop(cr->cr_ruidinfo);
1058 cr->cr_ruidinfo = NULL;
1062 * Destroy empty prisons
1065 prison_free(cr->cr_prison);
1066 cr->cr_prison = NULL; /* safety */
1068 kfree((caddr_t)cr, M_CRED);
1073 * Atomize a cred structure so it can be modified without polluting
1074 * other references to it.
1076 * MPSAFE (however, *pcr must be stable)
1079 cratom(struct ucred **pcr)
1081 struct ucred *oldcr;
1082 struct ucred *newcr;
1085 if (oldcr->cr_ref == 1)
1089 if (newcr->cr_uidinfo)
1090 uihold(newcr->cr_uidinfo);
1091 if (newcr->cr_ruidinfo)
1092 uihold(newcr->cr_ruidinfo);
1094 prison_hold(newcr->cr_prison);
1101 #if 0 /* no longer used but keep around for a little while */
1103 * Copy cred structure to a new one and free the old one.
1105 * MPSAFE (*cr must be stable)
1108 crcopy(struct ucred *cr)
1110 struct ucred *newcr;
1112 if (cr->cr_ref == 1)
1116 if (newcr->cr_uidinfo)
1117 uihold(newcr->cr_uidinfo);
1118 if (newcr->cr_ruidinfo)
1119 uihold(newcr->cr_ruidinfo);
1121 prison_hold(newcr->cr_prison);
1129 * Dup cred struct to a new held one.
1132 crdup(struct ucred *cr)
1134 struct ucred *newcr;
1138 if (newcr->cr_uidinfo)
1139 uihold(newcr->cr_uidinfo);
1140 if (newcr->cr_ruidinfo)
1141 uihold(newcr->cr_ruidinfo);
1143 prison_hold(newcr->cr_prison);
1149 * Fill in a struct xucred based on a struct ucred.
1152 cru2x(struct ucred *cr, struct xucred *xcr)
1155 bzero(xcr, sizeof(*xcr));
1156 xcr->cr_version = XUCRED_VERSION;
1157 xcr->cr_uid = cr->cr_uid;
1158 xcr->cr_ngroups = cr->cr_ngroups;
1159 bcopy(cr->cr_groups, xcr->cr_groups, sizeof(cr->cr_groups));
1163 * Get login name, if available.
1166 sys_getlogin(struct getlogin_args *uap)
1168 struct proc *p = curproc;
1169 char buf[MAXLOGNAME];
1172 if (uap->namelen > MAXLOGNAME) /* namelen is unsigned */
1173 uap->namelen = MAXLOGNAME;
1174 bzero(buf, sizeof(buf));
1175 lwkt_gettoken_shared(&p->p_token);
1176 bcopy(p->p_pgrp->pg_session->s_login, buf, uap->namelen);
1177 lwkt_reltoken(&p->p_token);
1179 error = copyout(buf, uap->namebuf, uap->namelen);
1187 sys_setlogin(struct setlogin_args *uap)
1189 struct thread *td = curthread;
1192 char buf[MAXLOGNAME];
1195 cred = td->td_ucred;
1198 if ((error = priv_check_cred(cred, PRIV_PROC_SETLOGIN, 0)))
1200 bzero(buf, sizeof(buf));
1201 error = copyinstr(uap->namebuf, buf, sizeof(buf), NULL);
1202 if (error == ENAMETOOLONG)
1205 lwkt_gettoken_shared(&p->p_token);
1206 memcpy(p->p_pgrp->pg_session->s_login, buf, sizeof(buf));
1207 lwkt_reltoken(&p->p_token);
1215 struct proc *p = curproc;
1217 KKASSERT(p != NULL);
1218 lwkt_gettoken(&p->p_token);
1219 p->p_flags |= P_SUGID;
1220 if (!(p->p_pfsflags & PF_ISUGID))
1222 lwkt_reltoken(&p->p_token);
1226 * Helper function to change the effective uid of a process
1229 change_euid(uid_t euid)
1231 struct proc *p = curproc;
1234 KKASSERT(p != NULL);
1235 lf_count_adjust(p, 0);
1236 cr = cratom(&p->p_ucred);
1238 uireplace(&cr->cr_uidinfo, uifind(euid));
1239 lf_count_adjust(p, 1);
1244 * Helper function to change the real uid of a process
1246 * The per-uid process count for this process is transfered from
1247 * the old uid to the new uid.
1250 change_ruid(uid_t ruid)
1252 struct proc *p = curproc;
1255 KKASSERT(p != NULL);
1257 cr = cratom(&p->p_ucred);
1258 chgproccnt(cr->cr_ruidinfo, -1, 0);
1260 uireplace(&cr->cr_ruidinfo, uifind(ruid));
1261 chgproccnt(cr->cr_ruidinfo, 1, 0);