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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);
91 sys_lwp_gettid(struct lwp_gettid_args *uap)
93 struct lwp *lp = curthread->td_lwp;
94 uap->sysmsg_result = lp->lwp_tid;
99 * Get process group ID; note that POSIX getpgrp takes no parameter
102 sys_getpgrp(struct getpgrp_args *uap)
104 struct proc *p = curproc;
106 lwkt_gettoken_shared(&p->p_token);
107 uap->sysmsg_result = p->p_pgrp->pg_id;
108 lwkt_reltoken(&p->p_token);
114 * Get an arbitrary pid's process group id
117 sys_getpgid(struct getpgid_args *uap)
119 struct proc *p = curproc;
129 pt = pfind(uap->pid);
134 lwkt_gettoken_shared(&pt->p_token);
135 uap->sysmsg_result = pt->p_pgrp->pg_id;
136 lwkt_reltoken(&pt->p_token);
144 * Get an arbitrary pid's session id.
147 sys_getsid(struct getsid_args *uap)
149 struct proc *p = curproc;
159 pt = pfind(uap->pid);
164 uap->sysmsg_result = pt->p_session->s_sid;
175 sys_getuid(struct getuid_args *uap)
177 struct ucred *cred = curthread->td_ucred;
179 uap->sysmsg_fds[0] = cred->cr_ruid;
180 #if defined(COMPAT_43)
181 uap->sysmsg_fds[1] = cred->cr_uid;
190 sys_geteuid(struct geteuid_args *uap)
192 struct ucred *cred = curthread->td_ucred;
194 uap->sysmsg_result = cred->cr_uid;
202 sys_getgid(struct getgid_args *uap)
204 struct ucred *cred = curthread->td_ucred;
206 uap->sysmsg_fds[0] = cred->cr_rgid;
207 #if defined(COMPAT_43)
208 uap->sysmsg_fds[1] = cred->cr_groups[0];
214 * Get effective group ID. The "egid" is groups[0], and could be obtained
215 * via getgroups. This syscall exists because it is somewhat painful to do
216 * correctly in a library function.
219 sys_getegid(struct getegid_args *uap)
221 struct ucred *cred = curthread->td_ucred;
223 uap->sysmsg_result = cred->cr_groups[0];
228 sys_getgroups(struct getgroups_args *uap)
234 cr = curthread->td_ucred;
235 if ((ngrp = uap->gidsetsize) == 0) {
236 uap->sysmsg_result = cr->cr_ngroups;
239 if (ngrp < cr->cr_ngroups)
241 ngrp = cr->cr_ngroups;
242 error = copyout((caddr_t)cr->cr_groups,
243 (caddr_t)uap->gidset, ngrp * sizeof(gid_t));
245 uap->sysmsg_result = ngrp;
250 sys_lwp_setname(struct lwp_setname_args *uap)
252 struct proc *p = curproc;
253 char comm0[MAXCOMLEN + 1];
254 const char *comm = NULL;
258 if (uap->name != NULL) {
259 error = copyinstr(uap->name, comm0, sizeof(comm0), NULL);
261 if (error != ENAMETOOLONG)
264 comm0[MAXCOMLEN] = '\0';
268 /* Restore to the default name, i.e. process name. */
272 lwkt_gettoken(&p->p_token);
274 lp = lwp_rb_tree_RB_LOOKUP(&p->p_lwp_tree, uap->tid);
276 strlcpy(lp->lwp_thread->td_comm, comm,
277 sizeof(lp->lwp_thread->td_comm));
283 lwkt_reltoken(&p->p_token);
288 sys_setsid(struct setsid_args *uap)
290 struct proc *p = curproc;
291 struct pgrp *pg = NULL;
294 lwkt_gettoken(&p->p_token);
295 if (p->p_pgid == p->p_pid || (pg = pgfind(p->p_pid)) != NULL) {
300 enterpgrp(p, p->p_pid, 1);
301 uap->sysmsg_result = p->p_pid;
304 lwkt_reltoken(&p->p_token);
309 * set process group (setpgid/old setpgrp)
311 * caller does setpgid(targpid, targpgid)
313 * pid must be caller or child of caller (ESRCH)
315 * pid must be in same session (EPERM)
316 * pid can't have done an exec (EACCES)
318 * there must exist some pid in same session having pgid (EPERM)
319 * pid must not be session leader (EPERM)
322 sys_setpgid(struct setpgid_args *uap)
324 struct proc *curp = curproc;
325 struct proc *targp; /* target process */
326 struct pgrp *pgrp = NULL; /* target pgrp */
332 if (uap->pid != 0 && uap->pid != curp->p_pid) {
333 if ((targp = pfind(uap->pid)) == NULL || !inferior(targp)) {
340 lwkt_gettoken(&targp->p_token);
341 /* targp now referenced and its token is held */
343 if (targp->p_pgrp == NULL ||
344 targp->p_session != curp->p_session) {
348 if (targp->p_flags & P_EXEC) {
355 lwkt_gettoken(&targp->p_token);
357 if (SESS_LEADER(targp)) {
361 if (uap->pgid == 0) {
362 uap->pgid = targp->p_pid;
363 } else if (uap->pgid != targp->p_pid) {
364 if ((pgrp = pgfind(uap->pgid)) == NULL ||
365 pgrp->pg_session != curp->p_session) {
370 error = enterpgrp(targp, uap->pgid, 0);
375 lwkt_reltoken(&targp->p_token);
382 * Use the clause in B.4.2.2 that allows setuid/setgid to be 4.2/4.3BSD
383 * compatible. It says that setting the uid/gid to euid/egid is a special
384 * case of "appropriate privilege". Once the rules are expanded out, this
385 * basically means that setuid(nnn) sets all three id's, in all permitted
386 * cases unless _POSIX_SAVED_IDS is enabled. In that case, setuid(getuid())
387 * does not set the saved id - this is dangerous for traditional BSD
388 * programs. For this reason, we *really* do not want to set
389 * _POSIX_SAVED_IDS and do not want to clear POSIX_APPENDIX_B_4_2_2.
391 #define POSIX_APPENDIX_B_4_2_2
394 sys_setuid(struct setuid_args *uap)
396 struct proc *p = curproc;
401 lwkt_gettoken(&p->p_token);
405 * See if we have "permission" by POSIX 1003.1 rules.
407 * Note that setuid(geteuid()) is a special case of
408 * "appropriate privileges" in appendix B.4.2.2. We need
409 * to use this clause to be compatible with traditional BSD
410 * semantics. Basically, it means that "setuid(xx)" sets all
411 * three id's (assuming you have privs).
413 * Notes on the logic. We do things in three steps.
414 * 1: We determine if the euid is going to change, and do EPERM
415 * right away. We unconditionally change the euid later if this
416 * test is satisfied, simplifying that part of the logic.
417 * 2: We determine if the real and/or saved uid's are going to
418 * change. Determined by compile options.
419 * 3: Change euid last. (after tests in #2 for "appropriate privs")
422 if (uid != cr->cr_ruid && /* allow setuid(getuid()) */
423 #ifdef _POSIX_SAVED_IDS
424 uid != crc->cr_svuid && /* allow setuid(saved gid) */
426 #ifdef POSIX_APPENDIX_B_4_2_2 /* Use BSD-compat clause from B.4.2.2 */
427 uid != cr->cr_uid && /* allow setuid(geteuid()) */
429 (error = priv_check_cred(cr, PRIV_CRED_SETUID, 0)))
432 #ifdef _POSIX_SAVED_IDS
434 * Do we have "appropriate privileges" (are we root or uid == euid)
435 * If so, we are changing the real uid and/or saved uid.
438 #ifdef POSIX_APPENDIX_B_4_2_2 /* Use the clause from B.4.2.2 */
441 priv_check_cred(cr, PRIV_CRED_SETUID, 0) == 0) /* we are using privs */
445 * Set the real uid and transfer proc count to new user.
447 if (uid != cr->cr_ruid) {
448 cr = change_ruid(uid);
454 * XXX always set saved uid even if not _POSIX_SAVED_IDS, as
455 * the security of seteuid() depends on it. B.4.2.2 says it
456 * is important that we should do this.
458 if (cr->cr_svuid != uid) {
466 * In all permitted cases, we are changing the euid.
467 * Copy credentials so other references do not see our changes.
469 if (cr->cr_uid != uid) {
475 lwkt_reltoken(&p->p_token);
480 sys_seteuid(struct seteuid_args *uap)
482 struct proc *p = curproc;
487 lwkt_gettoken(&p->p_token);
490 if (euid != cr->cr_ruid && /* allow seteuid(getuid()) */
491 euid != cr->cr_svuid && /* allow seteuid(saved uid) */
492 (error = priv_check_cred(cr, PRIV_CRED_SETEUID, 0))) {
493 lwkt_reltoken(&p->p_token);
498 * Everything's okay, do it. Copy credentials so other references do
499 * not see our changes.
501 if (cr->cr_uid != euid) {
505 lwkt_reltoken(&p->p_token);
510 sys_setgid(struct setgid_args *uap)
512 struct proc *p = curproc;
517 lwkt_gettoken(&p->p_token);
521 * See if we have "permission" by POSIX 1003.1 rules.
523 * Note that setgid(getegid()) is a special case of
524 * "appropriate privileges" in appendix B.4.2.2. We need
525 * to use this clause to be compatible with traditional BSD
526 * semantics. Basically, it means that "setgid(xx)" sets all
527 * three id's (assuming you have privs).
529 * For notes on the logic here, see setuid() above.
532 if (gid != cr->cr_rgid && /* allow setgid(getgid()) */
533 #ifdef _POSIX_SAVED_IDS
534 gid != cr->cr_svgid && /* allow setgid(saved gid) */
536 #ifdef POSIX_APPENDIX_B_4_2_2 /* Use BSD-compat clause from B.4.2.2 */
537 gid != cr->cr_groups[0] && /* allow setgid(getegid()) */
539 (error = priv_check_cred(cr, PRIV_CRED_SETGID, 0))) {
543 #ifdef _POSIX_SAVED_IDS
545 * Do we have "appropriate privileges" (are we root or gid == egid)
546 * If so, we are changing the real uid and saved gid.
549 #ifdef POSIX_APPENDIX_B_4_2_2 /* use the clause from B.4.2.2 */
550 gid == cr->cr_groups[0] ||
552 priv_check_cred(cr, PRIV_CRED_SETGID, 0) == 0) /* we are using privs */
558 if (cr->cr_rgid != gid) {
566 * XXX always set saved gid even if not _POSIX_SAVED_IDS, as
567 * the security of setegid() depends on it. B.4.2.2 says it
568 * is important that we should do this.
570 if (cr->cr_svgid != gid) {
577 * In all cases permitted cases, we are changing the egid.
578 * Copy credentials so other references do not see our changes.
580 if (cr->cr_groups[0] != gid) {
582 cr->cr_groups[0] = gid;
587 lwkt_reltoken(&p->p_token);
592 sys_setegid(struct setegid_args *uap)
594 struct proc *p = curproc;
599 lwkt_gettoken(&p->p_token);
602 if (egid != cr->cr_rgid && /* allow setegid(getgid()) */
603 egid != cr->cr_svgid && /* allow setegid(saved gid) */
604 (error = priv_check_cred(cr, PRIV_CRED_SETEGID, 0))) {
607 if (cr->cr_groups[0] != egid) {
609 cr->cr_groups[0] = egid;
614 lwkt_reltoken(&p->p_token);
619 sys_setgroups(struct setgroups_args *uap)
621 struct proc *p = curproc;
626 lwkt_gettoken(&p->p_token);
629 if ((error = priv_check_cred(cr, PRIV_CRED_SETGROUPS, 0)))
631 ngrp = uap->gidsetsize;
632 if (ngrp > NGROUPS) {
637 * XXX A little bit lazy here. We could test if anything has
638 * changed before cratom() and setting P_SUGID.
643 * setgroups(0, NULL) is a legitimate way of clearing the
644 * groups vector on non-BSD systems (which generally do not
645 * have the egid in the groups[0]). We risk security holes
646 * when running non-BSD software if we do not do the same.
650 error = copyin(uap->gidset, cr->cr_groups,
651 ngrp * sizeof(gid_t));
654 cr->cr_ngroups = ngrp;
659 lwkt_reltoken(&p->p_token);
664 sys_setreuid(struct setreuid_args *uap)
666 struct proc *p = curproc;
671 lwkt_gettoken(&p->p_token);
676 if (((ruid != (uid_t)-1 && ruid != cr->cr_ruid &&
677 ruid != cr->cr_svuid) ||
678 (euid != (uid_t)-1 && euid != cr->cr_uid &&
679 euid != cr->cr_ruid && euid != cr->cr_svuid)) &&
680 (error = priv_check_cred(cr, PRIV_CRED_SETREUID, 0)) != 0) {
684 if (euid != (uid_t)-1 && cr->cr_uid != euid) {
685 cr = change_euid(euid);
688 if (ruid != (uid_t)-1 && cr->cr_ruid != ruid) {
689 cr = change_ruid(ruid);
692 if ((ruid != (uid_t)-1 || cr->cr_uid != cr->cr_ruid) &&
693 cr->cr_svuid != cr->cr_uid) {
695 cr->cr_svuid = cr->cr_uid;
700 lwkt_reltoken(&p->p_token);
705 sys_setregid(struct setregid_args *uap)
707 struct proc *p = curproc;
712 lwkt_gettoken(&p->p_token);
717 if (((rgid != (gid_t)-1 && rgid != cr->cr_rgid &&
718 rgid != cr->cr_svgid) ||
719 (egid != (gid_t)-1 && egid != cr->cr_groups[0] &&
720 egid != cr->cr_rgid && egid != cr->cr_svgid)) &&
721 (error = priv_check_cred(cr, PRIV_CRED_SETREGID, 0)) != 0) {
725 if (egid != (gid_t)-1 && cr->cr_groups[0] != egid) {
727 cr->cr_groups[0] = egid;
730 if (rgid != (gid_t)-1 && cr->cr_rgid != rgid) {
735 if ((rgid != (gid_t)-1 || cr->cr_groups[0] != cr->cr_rgid) &&
736 cr->cr_svgid != cr->cr_groups[0]) {
738 cr->cr_svgid = cr->cr_groups[0];
743 lwkt_reltoken(&p->p_token);
748 * setresuid(ruid, euid, suid) is like setreuid except control over the
749 * saved uid is explicit.
752 sys_setresuid(struct setresuid_args *uap)
754 struct proc *p = curproc;
756 uid_t ruid, euid, suid;
759 lwkt_gettoken(&p->p_token);
765 if (((ruid != (uid_t)-1 && ruid != cr->cr_ruid &&
766 ruid != cr->cr_svuid && ruid != cr->cr_uid) ||
767 (euid != (uid_t)-1 && euid != cr->cr_ruid &&
768 euid != cr->cr_svuid && euid != cr->cr_uid) ||
769 (suid != (uid_t)-1 && suid != cr->cr_ruid &&
770 suid != cr->cr_svuid && suid != cr->cr_uid)) &&
771 (error = priv_check_cred(cr, PRIV_CRED_SETRESUID, 0)) != 0) {
774 if (euid != (uid_t)-1 && cr->cr_uid != euid) {
775 cr = change_euid(euid);
778 if (ruid != (uid_t)-1 && cr->cr_ruid != ruid) {
779 cr = change_ruid(ruid);
782 if (suid != (uid_t)-1 && cr->cr_svuid != suid) {
789 lwkt_reltoken(&p->p_token);
794 * setresgid(rgid, egid, sgid) is like setregid except control over the
795 * saved gid is explicit.
798 sys_setresgid(struct setresgid_args *uap)
800 struct proc *p = curproc;
802 gid_t rgid, egid, sgid;
805 lwkt_gettoken(&p->p_token);
810 if (((rgid != (gid_t)-1 && rgid != cr->cr_rgid &&
811 rgid != cr->cr_svgid && rgid != cr->cr_groups[0]) ||
812 (egid != (gid_t)-1 && egid != cr->cr_rgid &&
813 egid != cr->cr_svgid && egid != cr->cr_groups[0]) ||
814 (sgid != (gid_t)-1 && sgid != cr->cr_rgid &&
815 sgid != cr->cr_svgid && sgid != cr->cr_groups[0])) &&
816 (error = priv_check_cred(cr, PRIV_CRED_SETRESGID, 0)) != 0) {
820 if (egid != (gid_t)-1 && cr->cr_groups[0] != egid) {
822 cr->cr_groups[0] = egid;
825 if (rgid != (gid_t)-1 && cr->cr_rgid != rgid) {
830 if (sgid != (gid_t)-1 && cr->cr_svgid != sgid) {
837 lwkt_reltoken(&p->p_token);
842 sys_getresuid(struct getresuid_args *uap)
845 int error1 = 0, error2 = 0, error3 = 0;
848 * copyout's can fault synchronously so we cannot use a shared
851 cr = curthread->td_ucred;
853 error1 = copyout((caddr_t)&cr->cr_ruid,
854 (caddr_t)uap->ruid, sizeof(cr->cr_ruid));
856 error2 = copyout((caddr_t)&cr->cr_uid,
857 (caddr_t)uap->euid, sizeof(cr->cr_uid));
859 error3 = copyout((caddr_t)&cr->cr_svuid,
860 (caddr_t)uap->suid, sizeof(cr->cr_svuid));
861 return error1 ? error1 : (error2 ? error2 : error3);
865 sys_getresgid(struct getresgid_args *uap)
868 int error1 = 0, error2 = 0, error3 = 0;
870 cr = curthread->td_ucred;
872 error1 = copyout(&cr->cr_rgid, uap->rgid,
873 sizeof(cr->cr_rgid));
875 error2 = copyout(&cr->cr_groups[0], uap->egid,
876 sizeof(cr->cr_groups[0]));
878 error3 = copyout(&cr->cr_svgid, uap->sgid,
879 sizeof(cr->cr_svgid));
880 return error1 ? error1 : (error2 ? error2 : error3);
885 * NOTE: OpenBSD sets a P_SUGIDEXEC flag set at execve() time,
886 * we use P_SUGID because we consider changing the owners as
887 * "tainting" as well.
888 * This is significant for procs that start as root and "become"
889 * a user without an exec - programs cannot know *everything*
890 * that libc *might* have put in their data segment.
893 sys_issetugid(struct issetugid_args *uap)
895 uap->sysmsg_result = (curproc->p_flags & P_SUGID) ? 1 : 0;
900 * Check if gid is a member of the group set.
903 groupmember(gid_t gid, struct ucred *cred)
908 egp = &(cred->cr_groups[cred->cr_ngroups]);
909 for (gp = cred->cr_groups; gp < egp; gp++) {
917 * Test whether the specified credentials have the privilege
920 * A kernel thread without a process context is assumed to have
921 * the privilege in question. In situations where the caller always
922 * expect a cred to exist, the cred should be passed separately and
923 * priv_check_cred() should be used instead of priv_check().
925 * Returns 0 or error.
928 priv_check(struct thread *td, int priv)
930 if (td->td_lwp != NULL)
931 return priv_check_cred(td->td_ucred, priv, 0);
936 * Check a credential for privilege.
938 * A non-null credential is expected unless NULL_CRED_OKAY is set.
941 priv_check_cred(struct ucred *cred, int priv, int flags)
945 KASSERT(PRIV_VALID(priv), ("priv_check_cred: invalid privilege"));
947 KASSERT(cred != NULL || (flags & NULL_CRED_OKAY),
948 ("priv_check_cred: NULL cred!"));
951 if (flags & NULL_CRED_OKAY)
956 if (cred->cr_uid != 0)
959 error = prison_priv_check(cred, priv);
963 /* NOTE: accounting for suser access (p_acflag/ASU) removed */
968 * Return zero if p1 can fondle p2, return errno (EPERM/ESRCH) otherwise.
971 p_trespass(struct ucred *cr1, struct ucred *cr2)
975 if (!PRISON_CHECK(cr1, cr2))
977 if (cr1->cr_ruid == cr2->cr_ruid)
979 if (cr1->cr_uid == cr2->cr_ruid)
981 if (cr1->cr_ruid == cr2->cr_uid)
983 if (cr1->cr_uid == cr2->cr_uid)
985 if (priv_check_cred(cr1, PRIV_PROC_TRESPASS, 0) == 0)
991 _crinit(struct ucred *cr)
997 crinit(struct ucred *cr)
999 bzero(cr, sizeof(*cr));
1004 * Allocate a zeroed cred structure.
1011 cr = kmalloc(sizeof(*cr), M_CRED, M_WAITOK|M_ZERO);
1017 * Claim another reference to a ucred structure. Can be used with special
1020 * It must be possible to call this routine with spinlocks held, meaning
1021 * 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.
1040 crfree(struct ucred *cr)
1042 if (cr->cr_ref <= 0)
1043 panic("Freeing already free credential! %p", cr);
1044 if (atomic_fetchadd_int(&cr->cr_ref, -1) == 1) {
1046 * Some callers of crget(), such as nfs_statfs(),
1047 * allocate a temporary credential, but don't
1048 * allocate a uidinfo structure.
1050 if (cr->cr_uidinfo != NULL) {
1051 uidrop(cr->cr_uidinfo);
1052 cr->cr_uidinfo = NULL;
1054 if (cr->cr_ruidinfo != NULL) {
1055 uidrop(cr->cr_ruidinfo);
1056 cr->cr_ruidinfo = NULL;
1060 * Destroy empty prisons
1063 prison_free(cr->cr_prison);
1064 cr->cr_prison = NULL; /* safety */
1066 kfree((caddr_t)cr, M_CRED);
1071 * Atomize a cred structure so it can be modified without polluting
1072 * other references to it.
1074 * MPSAFE (however, *pcr must be stable)
1077 cratom(struct ucred **pcr)
1079 struct ucred *oldcr;
1080 struct ucred *newcr;
1083 if (oldcr->cr_ref == 1)
1085 newcr = crget(); /* this might block */
1086 oldcr = *pcr; /* re-cache after potentially blocking */
1088 if (newcr->cr_uidinfo)
1089 uihold(newcr->cr_uidinfo);
1090 if (newcr->cr_ruidinfo)
1091 uihold(newcr->cr_ruidinfo);
1093 prison_hold(newcr->cr_prison);
1102 * Called with a modifying token held, but must still obtain p_spin to
1103 * actually replace p_ucred to handle races against syscall entry from
1104 * other threads which cache p_ucred->td_ucred.
1106 * (the threads will only get the spin-lock, and they only need to in
1107 * the case where td_ucred != p_ucred so this is optimal).
1110 cratom_proc(struct proc *p)
1112 struct ucred *oldcr;
1113 struct ucred *newcr;
1116 if (oldcr->cr_ref == 1)
1119 newcr = crget(); /* this might block */
1120 oldcr = p->p_ucred; /* so re-cache oldcr (do not re-test) */
1122 if (newcr->cr_uidinfo)
1123 uihold(newcr->cr_uidinfo);
1124 if (newcr->cr_ruidinfo)
1125 uihold(newcr->cr_ruidinfo);
1127 prison_hold(newcr->cr_prison);
1130 spin_lock(&p->p_spin);
1132 spin_unlock(&p->p_spin);
1139 * Dup cred struct to a new held one.
1142 crdup(struct ucred *cr)
1144 struct ucred *newcr;
1148 if (newcr->cr_uidinfo)
1149 uihold(newcr->cr_uidinfo);
1150 if (newcr->cr_ruidinfo)
1151 uihold(newcr->cr_ruidinfo);
1153 prison_hold(newcr->cr_prison);
1159 * Fill in a struct xucred based on a struct ucred.
1162 cru2x(struct ucred *cr, struct xucred *xcr)
1165 bzero(xcr, sizeof(*xcr));
1166 xcr->cr_version = XUCRED_VERSION;
1167 xcr->cr_uid = cr->cr_uid;
1168 xcr->cr_ngroups = cr->cr_ngroups;
1169 bcopy(cr->cr_groups, xcr->cr_groups, sizeof(cr->cr_groups));
1173 * Get login name, if available.
1176 sys_getlogin(struct getlogin_args *uap)
1178 struct proc *p = curproc;
1179 char buf[MAXLOGNAME];
1182 if (uap->namelen > MAXLOGNAME) /* namelen is unsigned */
1183 uap->namelen = MAXLOGNAME;
1184 bzero(buf, sizeof(buf));
1185 lwkt_gettoken_shared(&p->p_token);
1186 bcopy(p->p_pgrp->pg_session->s_login, buf, uap->namelen);
1187 lwkt_reltoken(&p->p_token);
1189 error = copyout(buf, uap->namebuf, uap->namelen);
1197 sys_setlogin(struct setlogin_args *uap)
1199 struct thread *td = curthread;
1202 char buf[MAXLOGNAME];
1205 cred = td->td_ucred;
1208 if ((error = priv_check_cred(cred, PRIV_PROC_SETLOGIN, 0)))
1210 bzero(buf, sizeof(buf));
1211 error = copyinstr(uap->namebuf, buf, sizeof(buf), NULL);
1212 if (error == ENAMETOOLONG)
1215 lwkt_gettoken_shared(&p->p_token);
1216 memcpy(p->p_pgrp->pg_session->s_login, buf, sizeof(buf));
1217 lwkt_reltoken(&p->p_token);
1225 struct proc *p = curproc;
1227 KKASSERT(p != NULL);
1228 lwkt_gettoken(&p->p_token);
1229 p->p_flags |= P_SUGID;
1230 if (!(p->p_pfsflags & PF_ISUGID))
1232 lwkt_reltoken(&p->p_token);
1236 * Helper function to change the effective uid of a process
1239 change_euid(uid_t euid)
1241 struct proc *p = curproc;
1244 KKASSERT(p != NULL);
1245 lf_count_adjust(p, 0);
1246 cr = cratom_proc(p);
1248 uireplace(&cr->cr_uidinfo, uifind(euid));
1249 lf_count_adjust(p, 1);
1254 * Helper function to change the real uid of a process
1256 * The per-uid process count for this process is transfered from
1257 * the old uid to the new uid.
1260 change_ruid(uid_t ruid)
1262 struct proc *p = curproc;
1265 KKASSERT(p != NULL);
1267 cr = cratom_proc(p);
1268 chgproccnt(cr->cr_ruidinfo, -1, 0);
1270 uireplace(&cr->cr_ruidinfo, uifind(ruid));
1271 chgproccnt(cr->cr_ruidinfo, 1, 0);