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mirror of https://git.FreeBSD.org/src.git synced 2024-12-23 11:18:54 +00:00
freebsd/sys/kern/kern_prot.c
2001-12-06 21:58:47 +00:00

1844 lines
41 KiB
C

/*
* Copyright (c) 1982, 1986, 1989, 1990, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
* Copyright (c) 2000-2001 Robert N. M. Watson. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kern_prot.c 8.6 (Berkeley) 1/21/94
* $FreeBSD$
*/
/*
* System calls related to processes and protection
*/
#include "opt_compat.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/acct.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/sx.h>
#include <sys/sysproto.h>
#include <sys/jail.h>
#include <sys/malloc.h>
#include <sys/pioctl.h>
#include <sys/resourcevar.h>
#include <sys/sysctl.h>
static MALLOC_DEFINE(M_CRED, "cred", "credentials");
SYSCTL_NODE(_kern, OID_AUTO, security, CTLFLAG_RW, 0,
"Kernel security policy");
SYSCTL_NODE(_kern_security, OID_AUTO, bsd, CTLFLAG_RW, 0,
"BSD security policy");
#ifndef _SYS_SYSPROTO_H_
struct getpid_args {
int dummy;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
getpid(td, uap)
struct thread *td;
struct getpid_args *uap;
{
struct proc *p = td->td_proc;
int s;
s = mtx_lock_giant(kern_giant_proc);
td->td_retval[0] = p->p_pid;
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
PROC_LOCK(p);
td->td_retval[1] = p->p_pptr->p_pid;
PROC_UNLOCK(p);
#endif
mtx_unlock_giant(s);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct getppid_args {
int dummy;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
getppid(td, uap)
struct thread *td;
struct getppid_args *uap;
{
struct proc *p = td->td_proc;
int s;
s = mtx_lock_giant(kern_giant_proc);
PROC_LOCK(p);
td->td_retval[0] = p->p_pptr->p_pid;
PROC_UNLOCK(p);
mtx_unlock_giant(s);
return (0);
}
/*
* Get process group ID; note that POSIX getpgrp takes no parameter.
*/
#ifndef _SYS_SYSPROTO_H_
struct getpgrp_args {
int dummy;
};
#endif
/*
* MPSAFE
*/
int
getpgrp(td, uap)
struct thread *td;
struct getpgrp_args *uap;
{
struct proc *p = td->td_proc;
mtx_lock(&Giant);
td->td_retval[0] = p->p_pgrp->pg_id;
mtx_unlock(&Giant);
return (0);
}
/* Get an arbitary pid's process group id */
#ifndef _SYS_SYSPROTO_H_
struct getpgid_args {
pid_t pid;
};
#endif
/*
* MPSAFE
*/
int
getpgid(td, uap)
struct thread *td;
struct getpgid_args *uap;
{
struct proc *p = td->td_proc;
struct proc *pt;
int error, s;
s = mtx_lock_giant(kern_giant_proc);
error = 0;
if (uap->pid == 0)
td->td_retval[0] = p->p_pgrp->pg_id;
else if ((pt = pfind(uap->pid)) == NULL)
error = ESRCH;
else {
error = p_cansee(p, pt);
if (error == 0)
td->td_retval[0] = pt->p_pgrp->pg_id;
PROC_UNLOCK(pt);
}
mtx_unlock_giant(s);
return (error);
}
/*
* Get an arbitary pid's session id.
*/
#ifndef _SYS_SYSPROTO_H_
struct getsid_args {
pid_t pid;
};
#endif
/*
* MPSAFE
*/
int
getsid(td, uap)
struct thread *td;
struct getsid_args *uap;
{
struct proc *p = td->td_proc;
struct proc *pt;
int error;
mtx_lock(&Giant);
error = 0;
if (uap->pid == 0)
td->td_retval[0] = p->p_session->s_sid;
else if ((pt = pfind(uap->pid)) == NULL)
error = ESRCH;
else {
error = p_cansee(p, pt);
if (error == 0)
td->td_retval[0] = pt->p_session->s_sid;
PROC_UNLOCK(pt);
}
mtx_unlock(&Giant);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct getuid_args {
int dummy;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
getuid(td, uap)
struct thread *td;
struct getuid_args *uap;
{
struct proc *p = td->td_proc;
mtx_lock(&Giant);
td->td_retval[0] = p->p_ucred->cr_ruid;
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
td->td_retval[1] = p->p_ucred->cr_uid;
#endif
mtx_unlock(&Giant);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct geteuid_args {
int dummy;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
geteuid(td, uap)
struct thread *td;
struct geteuid_args *uap;
{
mtx_lock(&Giant);
td->td_retval[0] = td->td_proc->p_ucred->cr_uid;
mtx_unlock(&Giant);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct getgid_args {
int dummy;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
getgid(td, uap)
struct thread *td;
struct getgid_args *uap;
{
struct proc *p = td->td_proc;
mtx_lock(&Giant);
td->td_retval[0] = p->p_ucred->cr_rgid;
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
td->td_retval[1] = p->p_ucred->cr_groups[0];
#endif
mtx_unlock(&Giant);
return (0);
}
/*
* Get effective group ID. The "egid" is groups[0], and could be obtained
* via getgroups. This syscall exists because it is somewhat painful to do
* correctly in a library function.
*/
#ifndef _SYS_SYSPROTO_H_
struct getegid_args {
int dummy;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
getegid(td, uap)
struct thread *td;
struct getegid_args *uap;
{
struct proc *p = td->td_proc;
mtx_lock(&Giant);
td->td_retval[0] = p->p_ucred->cr_groups[0];
mtx_unlock(&Giant);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct getgroups_args {
u_int gidsetsize;
gid_t *gidset;
};
#endif
/*
* MPSAFE
*/
int
getgroups(td, uap)
struct thread *td;
register struct getgroups_args *uap;
{
struct ucred *cred;
struct proc *p = td->td_proc;
u_int ngrp;
int error;
mtx_lock(&Giant);
error = 0;
cred = p->p_ucred;
if ((ngrp = uap->gidsetsize) == 0) {
td->td_retval[0] = cred->cr_ngroups;
goto done2;
}
if (ngrp < cred->cr_ngroups) {
error = EINVAL;
goto done2;
}
ngrp = cred->cr_ngroups;
if ((error = copyout((caddr_t)cred->cr_groups,
(caddr_t)uap->gidset, ngrp * sizeof(gid_t))))
goto done2;
td->td_retval[0] = ngrp;
done2:
mtx_unlock(&Giant);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct setsid_args {
int dummy;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setsid(td, uap)
register struct thread *td;
struct setsid_args *uap;
{
int error;
struct proc *p = td->td_proc;
mtx_lock(&Giant);
if (p->p_pgid == p->p_pid || pgfind(p->p_pid))
error = EPERM;
else {
(void)enterpgrp(p, p->p_pid, 1);
td->td_retval[0] = p->p_pid;
error = 0;
}
mtx_unlock(&Giant);
return (error);
}
/*
* set process group (setpgid/old setpgrp)
*
* caller does setpgid(targpid, targpgid)
*
* pid must be caller or child of caller (ESRCH)
* if a child
* pid must be in same session (EPERM)
* pid can't have done an exec (EACCES)
* if pgid != pid
* there must exist some pid in same session having pgid (EPERM)
* pid must not be session leader (EPERM)
*/
#ifndef _SYS_SYSPROTO_H_
struct setpgid_args {
int pid; /* target process id */
int pgid; /* target pgrp id */
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setpgid(td, uap)
struct thread *td;
register struct setpgid_args *uap;
{
struct proc *curp = td->td_proc;
register struct proc *targp; /* target process */
register struct pgrp *pgrp; /* target pgrp */
int error;
if (uap->pgid < 0)
return (EINVAL);
mtx_lock(&Giant);
sx_slock(&proctree_lock);
if (uap->pid != 0 && uap->pid != curp->p_pid) {
if ((targp = pfind(uap->pid)) == NULL || !inferior(targp)) {
if (targp)
PROC_UNLOCK(targp);
error = ESRCH;
goto done2;
}
if ((error = p_cansee(curproc, targp))) {
PROC_UNLOCK(targp);
goto done2;
}
if (targp->p_pgrp == NULL ||
targp->p_session != curp->p_session) {
PROC_UNLOCK(targp);
error = EPERM;
goto done2;
}
if (targp->p_flag & P_EXEC) {
PROC_UNLOCK(targp);
error = EACCES;
goto done2;
}
} else {
targp = curp;
PROC_LOCK(curp); /* XXX: not needed */
}
if (SESS_LEADER(targp)) {
PROC_UNLOCK(targp);
error = EPERM;
goto done2;
}
if (uap->pgid == 0)
uap->pgid = targp->p_pid;
else if (uap->pgid != targp->p_pid) {
if ((pgrp = pgfind(uap->pgid)) == 0 ||
pgrp->pg_session != curp->p_session) {
PROC_UNLOCK(targp);
error = EPERM;
goto done2;
}
}
/* XXX: We should probably hold the lock across enterpgrp. */
PROC_UNLOCK(targp);
error = enterpgrp(targp, uap->pgid, 0);
done2:
sx_sunlock(&proctree_lock);
mtx_unlock(&Giant);
return (error);
}
/*
* Use the clause in B.4.2.2 that allows setuid/setgid to be 4.2/4.3BSD
* compatible. It says that setting the uid/gid to euid/egid is a special
* case of "appropriate privilege". Once the rules are expanded out, this
* basically means that setuid(nnn) sets all three id's, in all permitted
* cases unless _POSIX_SAVED_IDS is enabled. In that case, setuid(getuid())
* does not set the saved id - this is dangerous for traditional BSD
* programs. For this reason, we *really* do not want to set
* _POSIX_SAVED_IDS and do not want to clear POSIX_APPENDIX_B_4_2_2.
*/
#define POSIX_APPENDIX_B_4_2_2
#ifndef _SYS_SYSPROTO_H_
struct setuid_args {
uid_t uid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setuid(td, uap)
struct thread *td;
struct setuid_args *uap;
{
struct proc *p = td->td_proc;
struct ucred *newcred, *oldcred;
uid_t uid;
int error;
uid = uap->uid;
mtx_lock(&Giant);
error = 0;
oldcred = p->p_ucred;
/*
* See if we have "permission" by POSIX 1003.1 rules.
*
* Note that setuid(geteuid()) is a special case of
* "appropriate privileges" in appendix B.4.2.2. We need
* to use this clause to be compatible with traditional BSD
* semantics. Basically, it means that "setuid(xx)" sets all
* three id's (assuming you have privs).
*
* Notes on the logic. We do things in three steps.
* 1: We determine if the euid is going to change, and do EPERM
* right away. We unconditionally change the euid later if this
* test is satisfied, simplifying that part of the logic.
* 2: We determine if the real and/or saved uids are going to
* change. Determined by compile options.
* 3: Change euid last. (after tests in #2 for "appropriate privs")
*/
if (uid != oldcred->cr_ruid && /* allow setuid(getuid()) */
#ifdef _POSIX_SAVED_IDS
uid != oldcred->cr_svuid && /* allow setuid(saved gid) */
#endif
#ifdef POSIX_APPENDIX_B_4_2_2 /* Use BSD-compat clause from B.4.2.2 */
uid != oldcred->cr_uid && /* allow setuid(geteuid()) */
#endif
(error = suser_xxx(oldcred, NULL, PRISON_ROOT)) != 0)
goto done2;
newcred = crdup(oldcred);
#ifdef _POSIX_SAVED_IDS
/*
* Do we have "appropriate privileges" (are we root or uid == euid)
* If so, we are changing the real uid and/or saved uid.
*/
if (
#ifdef POSIX_APPENDIX_B_4_2_2 /* Use the clause from B.4.2.2 */
uid == oldcred->cr_uid ||
#endif
suser_xxx(oldcred, NULL, PRISON_ROOT) == 0) /* we are using privs */
#endif
{
/*
* Set the real uid and transfer proc count to new user.
*/
if (uid != oldcred->cr_ruid) {
change_ruid(newcred, uid);
setsugid(p);
}
/*
* Set saved uid
*
* XXX always set saved uid even if not _POSIX_SAVED_IDS, as
* the security of seteuid() depends on it. B.4.2.2 says it
* is important that we should do this.
*/
if (uid != oldcred->cr_svuid) {
change_svuid(newcred, uid);
setsugid(p);
}
}
/*
* In all permitted cases, we are changing the euid.
* Copy credentials so other references do not see our changes.
*/
if (uid != oldcred->cr_uid) {
change_euid(newcred, uid);
setsugid(p);
}
p->p_ucred = newcred;
crfree(oldcred);
done2:
mtx_unlock(&Giant);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct seteuid_args {
uid_t euid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
seteuid(td, uap)
struct thread *td;
struct seteuid_args *uap;
{
struct proc *p = td->td_proc;
struct ucred *newcred, *oldcred;
uid_t euid;
int error;
euid = uap->euid;
mtx_lock(&Giant);
error = 0;
oldcred = p->p_ucred;
if (euid != oldcred->cr_ruid && /* allow seteuid(getuid()) */
euid != oldcred->cr_svuid && /* allow seteuid(saved uid) */
(error = suser_xxx(oldcred, NULL, PRISON_ROOT)) != 0)
goto done2;
/*
* Everything's okay, do it. Copy credentials so other references do
* not see our changes.
*/
newcred = crdup(oldcred);
if (oldcred->cr_uid != euid) {
change_euid(newcred, euid);
setsugid(p);
}
p->p_ucred = newcred;
crfree(oldcred);
done2:
mtx_unlock(&Giant);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct setgid_args {
gid_t gid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setgid(td, uap)
struct thread *td;
struct setgid_args *uap;
{
struct proc *p = td->td_proc;
struct ucred *newcred, *oldcred;
gid_t gid;
int error;
gid = uap->gid;
mtx_lock(&Giant);
error = 0;
oldcred = p->p_ucred;
/*
* See if we have "permission" by POSIX 1003.1 rules.
*
* Note that setgid(getegid()) is a special case of
* "appropriate privileges" in appendix B.4.2.2. We need
* to use this clause to be compatible with traditional BSD
* semantics. Basically, it means that "setgid(xx)" sets all
* three id's (assuming you have privs).
*
* For notes on the logic here, see setuid() above.
*/
if (gid != oldcred->cr_rgid && /* allow setgid(getgid()) */
#ifdef _POSIX_SAVED_IDS
gid != oldcred->cr_svgid && /* allow setgid(saved gid) */
#endif
#ifdef POSIX_APPENDIX_B_4_2_2 /* Use BSD-compat clause from B.4.2.2 */
gid != oldcred->cr_groups[0] && /* allow setgid(getegid()) */
#endif
(error = suser_xxx(oldcred, NULL, PRISON_ROOT)) != 0)
goto done2;
newcred = crdup(oldcred);
#ifdef _POSIX_SAVED_IDS
/*
* Do we have "appropriate privileges" (are we root or gid == egid)
* If so, we are changing the real uid and saved gid.
*/
if (
#ifdef POSIX_APPENDIX_B_4_2_2 /* use the clause from B.4.2.2 */
gid == oldcred->cr_groups[0] ||
#endif
suser_xxx(oldcred, NULL, PRISON_ROOT) == 0) /* we are using privs */
#endif
{
/*
* Set real gid
*/
if (oldcred->cr_rgid != gid) {
change_rgid(newcred, gid);
setsugid(p);
}
/*
* Set saved gid
*
* XXX always set saved gid even if not _POSIX_SAVED_IDS, as
* the security of setegid() depends on it. B.4.2.2 says it
* is important that we should do this.
*/
if (oldcred->cr_svgid != gid) {
change_svgid(newcred, gid);
setsugid(p);
}
}
/*
* In all cases permitted cases, we are changing the egid.
* Copy credentials so other references do not see our changes.
*/
if (oldcred->cr_groups[0] != gid) {
change_egid(newcred, gid);
setsugid(p);
}
p->p_ucred = newcred;
crfree(oldcred);
done2:
mtx_unlock(&Giant);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct setegid_args {
gid_t egid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setegid(td, uap)
struct thread *td;
struct setegid_args *uap;
{
struct proc *p = td->td_proc;
struct ucred *newcred, *oldcred;
gid_t egid;
int error;
egid = uap->egid;
mtx_lock(&Giant);
error = 0;
oldcred = p->p_ucred;
if (egid != oldcred->cr_rgid && /* allow setegid(getgid()) */
egid != oldcred->cr_svgid && /* allow setegid(saved gid) */
(error = suser_xxx(oldcred, NULL, PRISON_ROOT)) != 0)
goto done2;
newcred = crdup(oldcred);
if (oldcred->cr_groups[0] != egid) {
change_egid(newcred, egid);
setsugid(p);
}
p->p_ucred = newcred;
crfree(oldcred);
done2:
mtx_unlock(&Giant);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct setgroups_args {
u_int gidsetsize;
gid_t *gidset;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setgroups(td, uap)
struct thread *td;
struct setgroups_args *uap;
{
struct proc *p = td->td_proc;
struct ucred *newcred, *oldcred;
u_int ngrp;
int error;
ngrp = uap->gidsetsize;
mtx_lock(&Giant);
oldcred = p->p_ucred;
if ((error = suser_xxx(oldcred, NULL, PRISON_ROOT)) != 0)
goto done2;
if (ngrp > NGROUPS) {
error = EINVAL;
goto done2;
}
/*
* XXX A little bit lazy here. We could test if anything has
* changed before crcopy() and setting P_SUGID.
*/
newcred = crdup(oldcred);
if (ngrp < 1) {
/*
* setgroups(0, NULL) is a legitimate way of clearing the
* groups vector on non-BSD systems (which generally do not
* have the egid in the groups[0]). We risk security holes
* when running non-BSD software if we do not do the same.
*/
newcred->cr_ngroups = 1;
} else {
if ((error = copyin((caddr_t)uap->gidset,
(caddr_t)newcred->cr_groups, ngrp * sizeof(gid_t)))) {
crfree(newcred);
goto done2;
}
newcred->cr_ngroups = ngrp;
}
setsugid(p);
p->p_ucred = newcred;
crfree(oldcred);
done2:
mtx_unlock(&Giant);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct setreuid_args {
uid_t ruid;
uid_t euid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setreuid(td, uap)
register struct thread *td;
struct setreuid_args *uap;
{
struct proc *p = td->td_proc;
struct ucred *newcred, *oldcred;
uid_t euid, ruid;
int error;
euid = uap->euid;
ruid = uap->ruid;
mtx_lock(&Giant);
error = 0;
oldcred = p->p_ucred;
if (((ruid != (uid_t)-1 && ruid != oldcred->cr_ruid &&
ruid != oldcred->cr_svuid) ||
(euid != (uid_t)-1 && euid != oldcred->cr_uid &&
euid != oldcred->cr_ruid && euid != oldcred->cr_svuid)) &&
(error = suser_xxx(oldcred, NULL, PRISON_ROOT)) != 0)
goto done2;
newcred = crdup(oldcred);
if (euid != (uid_t)-1 && oldcred->cr_uid != euid) {
change_euid(newcred, euid);
setsugid(p);
}
if (ruid != (uid_t)-1 && oldcred->cr_ruid != ruid) {
change_ruid(newcred, ruid);
setsugid(p);
}
if ((ruid != (uid_t)-1 || newcred->cr_uid != newcred->cr_ruid) &&
newcred->cr_svuid != newcred->cr_uid) {
change_svuid(newcred, newcred->cr_uid);
setsugid(p);
}
p->p_ucred = newcred;
crfree(oldcred);
done2:
mtx_unlock(&Giant);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct setregid_args {
gid_t rgid;
gid_t egid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setregid(td, uap)
register struct thread *td;
struct setregid_args *uap;
{
struct proc *p = td->td_proc;
struct ucred *newcred, *oldcred;
gid_t egid, rgid;
int error;
egid = uap->egid;
rgid = uap->rgid;
mtx_lock(&Giant);
error = 0;
oldcred = p->p_ucred;
if (((rgid != (gid_t)-1 && rgid != oldcred->cr_rgid &&
rgid != oldcred->cr_svgid) ||
(egid != (gid_t)-1 && egid != oldcred->cr_groups[0] &&
egid != oldcred->cr_rgid && egid != oldcred->cr_svgid)) &&
(error = suser_xxx(oldcred, NULL, PRISON_ROOT)) != 0)
goto done2;
newcred = crdup(oldcred);
if (egid != (gid_t)-1 && oldcred->cr_groups[0] != egid) {
change_egid(newcred, egid);
setsugid(p);
}
if (rgid != (gid_t)-1 && oldcred->cr_rgid != rgid) {
change_rgid(newcred, rgid);
setsugid(p);
}
if ((rgid != (gid_t)-1 || newcred->cr_groups[0] != newcred->cr_rgid) &&
newcred->cr_svgid != newcred->cr_groups[0]) {
change_svgid(newcred, newcred->cr_groups[0]);
setsugid(p);
}
p->p_ucred = newcred;
crfree(oldcred);
done2:
mtx_unlock(&Giant);
return (error);
}
/*
* setresuid(ruid, euid, suid) is like setreuid except control over the
* saved uid is explicit.
*/
#ifndef _SYS_SYSPROTO_H_
struct setresuid_args {
uid_t ruid;
uid_t euid;
uid_t suid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setresuid(td, uap)
register struct thread *td;
struct setresuid_args *uap;
{
struct proc *p = td->td_proc;
struct ucred *newcred, *oldcred;
uid_t euid, ruid, suid;
int error;
euid = uap->euid;
ruid = uap->ruid;
suid = uap->suid;
mtx_lock(&Giant);
oldcred = p->p_ucred;
if (((ruid != (uid_t)-1 && ruid != oldcred->cr_ruid &&
ruid != oldcred->cr_svuid &&
ruid != oldcred->cr_uid) ||
(euid != (uid_t)-1 && euid != oldcred->cr_ruid &&
euid != oldcred->cr_svuid &&
euid != oldcred->cr_uid) ||
(suid != (uid_t)-1 && suid != oldcred->cr_ruid &&
suid != oldcred->cr_svuid &&
suid != oldcred->cr_uid)) &&
(error = suser_xxx(oldcred, NULL, PRISON_ROOT)) != 0)
goto done2;
newcred = crdup(oldcred);
if (euid != (uid_t)-1 && oldcred->cr_uid != euid) {
change_euid(newcred, euid);
setsugid(p);
}
if (ruid != (uid_t)-1 && oldcred->cr_ruid != ruid) {
change_ruid(newcred, ruid);
setsugid(p);
}
if (suid != (uid_t)-1 && oldcred->cr_svuid != suid) {
change_svuid(newcred, suid);
setsugid(p);
}
p->p_ucred = newcred;
crfree(oldcred);
error = 0;
done2:
mtx_unlock(&Giant);
return (error);
}
/*
* setresgid(rgid, egid, sgid) is like setregid except control over the
* saved gid is explicit.
*/
#ifndef _SYS_SYSPROTO_H_
struct setresgid_args {
gid_t rgid;
gid_t egid;
gid_t sgid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setresgid(td, uap)
register struct thread *td;
struct setresgid_args *uap;
{
struct proc *p = td->td_proc;
struct ucred *newcred, *oldcred;
gid_t egid, rgid, sgid;
int error;
egid = uap->egid;
rgid = uap->rgid;
sgid = uap->sgid;
mtx_lock(&Giant);
oldcred = p->p_ucred;
if (((rgid != (gid_t)-1 && rgid != oldcred->cr_rgid &&
rgid != oldcred->cr_svgid &&
rgid != oldcred->cr_groups[0]) ||
(egid != (gid_t)-1 && egid != oldcred->cr_rgid &&
egid != oldcred->cr_svgid &&
egid != oldcred->cr_groups[0]) ||
(sgid != (gid_t)-1 && sgid != oldcred->cr_rgid &&
sgid != oldcred->cr_svgid &&
sgid != oldcred->cr_groups[0])) &&
(error = suser_xxx(oldcred, NULL, PRISON_ROOT)) != 0)
goto done2;
newcred = crdup(oldcred);
if (egid != (gid_t)-1 && oldcred->cr_groups[0] != egid) {
change_egid(newcred, egid);
setsugid(p);
}
if (rgid != (gid_t)-1 && oldcred->cr_rgid != rgid) {
change_rgid(newcred, rgid);
setsugid(p);
}
if (sgid != (gid_t)-1 && oldcred->cr_svgid != sgid) {
change_svgid(newcred, sgid);
setsugid(p);
}
p->p_ucred = newcred;
crfree(oldcred);
error = 0;
done2:
mtx_unlock(&Giant);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct getresuid_args {
uid_t *ruid;
uid_t *euid;
uid_t *suid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
getresuid(td, uap)
register struct thread *td;
struct getresuid_args *uap;
{
struct ucred *cred;
struct proc *p = td->td_proc;
int error1 = 0, error2 = 0, error3 = 0;
mtx_lock(&Giant);
cred = p->p_ucred;
if (uap->ruid)
error1 = copyout((caddr_t)&cred->cr_ruid,
(caddr_t)uap->ruid, sizeof(cred->cr_ruid));
if (uap->euid)
error2 = copyout((caddr_t)&cred->cr_uid,
(caddr_t)uap->euid, sizeof(cred->cr_uid));
if (uap->suid)
error3 = copyout((caddr_t)&cred->cr_svuid,
(caddr_t)uap->suid, sizeof(cred->cr_svuid));
mtx_unlock(&Giant);
return (error1 ? error1 : error2 ? error2 : error3);
}
#ifndef _SYS_SYSPROTO_H_
struct getresgid_args {
gid_t *rgid;
gid_t *egid;
gid_t *sgid;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
getresgid(td, uap)
register struct thread *td;
struct getresgid_args *uap;
{
struct ucred *cred;
struct proc *p = td->td_proc;
int error1 = 0, error2 = 0, error3 = 0;
mtx_lock(&Giant);
cred = p->p_ucred;
if (uap->rgid)
error1 = copyout((caddr_t)&cred->cr_rgid,
(caddr_t)uap->rgid, sizeof(cred->cr_rgid));
if (uap->egid)
error2 = copyout((caddr_t)&cred->cr_groups[0],
(caddr_t)uap->egid, sizeof(cred->cr_groups[0]));
if (uap->sgid)
error3 = copyout((caddr_t)&cred->cr_svgid,
(caddr_t)uap->sgid, sizeof(cred->cr_svgid));
mtx_unlock(&Giant);
return (error1 ? error1 : error2 ? error2 : error3);
}
#ifndef _SYS_SYSPROTO_H_
struct issetugid_args {
int dummy;
};
#endif
/*
* NOT MPSAFE?
*/
/* ARGSUSED */
int
issetugid(td, uap)
register struct thread *td;
struct issetugid_args *uap;
{
struct proc *p = td->td_proc;
/*
* Note: OpenBSD sets a P_SUGIDEXEC flag set at execve() time,
* we use P_SUGID because we consider changing the owners as
* "tainting" as well.
* This is significant for procs that start as root and "become"
* a user without an exec - programs cannot know *everything*
* that libc *might* have put in their data segment.
*/
td->td_retval[0] = (p->p_flag & P_SUGID) ? 1 : 0;
return (0);
}
/*
* MPSAFE
*/
int
__setugid(td, uap)
struct thread *td;
struct __setugid_args *uap;
{
#ifdef REGRESSION
int error;
mtx_lock(&Giant);
error = 0;
switch (uap->flag) {
case 0:
td->td_proc->p_flag &= ~P_SUGID;
break;
case 1:
td->td_proc->p_flag |= P_SUGID;
break;
default:
error = EINVAL;
break;
}
mtx_unlock(&Giant);
return (error);
#else /* !REGRESSION */
return (ENOSYS);
#endif /* REGRESSION */
}
/*
* Check if gid is a member of the group set.
*/
int
groupmember(gid, cred)
gid_t gid;
struct ucred *cred;
{
register gid_t *gp;
gid_t *egp;
egp = &(cred->cr_groups[cred->cr_ngroups]);
for (gp = cred->cr_groups; gp < egp; gp++)
if (*gp == gid)
return (1);
return (0);
}
/*
* `suser_enabled' (which can be set by the kern.security.suser_enabled
* sysctl) determines whether the system 'super-user' policy is in effect.
* If it is nonzero, an effective uid of 0 connotes special privilege,
* overriding many mandatory and discretionary protections. If it is zero,
* uid 0 is offered no special privilege in the kernel security policy.
* Setting it to zero may seriously impact the functionality of many
* existing userland programs, and should not be done without careful
* consideration of the consequences.
*/
int suser_enabled = 1;
SYSCTL_INT(_kern_security_bsd, OID_AUTO, suser_enabled, CTLFLAG_RW,
&suser_enabled, 0, "processes with uid 0 have privilege");
TUNABLE_INT("kern.security.bsd.suser_enabled", &suser_enabled);
/*
* Test whether the specified credentials imply "super-user" privilege.
* Return 0 or EPERM.
*/
int
suser(p)
struct proc *p;
{
return (suser_xxx(0, p, 0));
}
/*
* version for when the thread pointer is available and not the proc.
* (saves having to include proc.h into every file that needs to do the change.)
*/
int
suser_td(td)
struct thread *td;
{
return (suser_xxx(0, td->td_proc, 0));
}
/*
* wrapper to use if you have the thread on hand but not the proc.
*/
int
suser_xxx_td(cred, td, flag)
struct ucred *cred;
struct thread *td;
int flag;
{
return(suser_xxx(cred, td->td_proc, flag));
}
int
suser_xxx(cred, proc, flag)
struct ucred *cred;
struct proc *proc;
int flag;
{
if (!suser_enabled)
return (EPERM);
if (!cred && !proc) {
printf("suser_xxx(): THINK!\n");
return (EPERM);
}
if (cred == NULL)
cred = proc->p_ucred;
if (cred->cr_uid != 0)
return (EPERM);
if (jailed(cred) && !(flag & PRISON_ROOT))
return (EPERM);
return (0);
}
/*
* Test the active securelevel against a given level. securelevel_gt()
* implements (securelevel > level). securelevel_ge() implements
* (securelevel >= level). Note that the logic is inverted -- these
* functions return EPERM on "success" and 0 on "failure".
*
* cr is permitted to be NULL for the time being, as there were some
* existing securelevel checks that occurred without a process/credential
* context. In the future this will be disallowed, so a kernel message
* is displayed.
*/
int
securelevel_gt(struct ucred *cr, int level)
{
int active_securelevel;
active_securelevel = securelevel;
if (cr == NULL)
printf("securelevel_gt: cr is NULL\n");
if (cr->cr_prison != NULL) {
mtx_lock(&cr->cr_prison->pr_mtx);
active_securelevel = imax(cr->cr_prison->pr_securelevel,
active_securelevel);
mtx_unlock(&cr->cr_prison->pr_mtx);
}
return (active_securelevel > level ? EPERM : 0);
}
int
securelevel_ge(struct ucred *cr, int level)
{
int active_securelevel;
active_securelevel = securelevel;
if (cr == NULL)
printf("securelevel_gt: cr is NULL\n");
if (cr->cr_prison != NULL) {
mtx_lock(&cr->cr_prison->pr_mtx);
active_securelevel = imax(cr->cr_prison->pr_securelevel,
active_securelevel);
mtx_unlock(&cr->cr_prison->pr_mtx);
}
return (active_securelevel >= level ? EPERM : 0);
}
/*
* 'see_other_uids' determines whether or not visibility of processes
* and sockets with credentials holding different real uids is possible
* using a variety of system MIBs.
* XXX: data declarations should be together near the beginning of the file.
*/
static int see_other_uids = 1;
SYSCTL_INT(_kern_security_bsd, OID_AUTO, see_other_uids, CTLFLAG_RW,
&see_other_uids, 0,
"Unprivileged processes may see subjects/objects with different real uid");
/*-
* Determine if u1 "can see" the subject specified by u2.
* Returns: 0 for permitted, an errno value otherwise
* Locks: none
* References: *u1 and *u2 must not change during the call
* u1 may equal u2, in which case only one reference is required
*/
int
cr_cansee(struct ucred *u1, struct ucred *u2)
{
int error;
if ((error = prison_check(u1, u2)))
return (error);
if (!see_other_uids && u1->cr_ruid != u2->cr_ruid) {
if (suser_xxx(u1, NULL, PRISON_ROOT) != 0)
return (ESRCH);
}
return (0);
}
/*-
* Determine if p1 "can see" the subject specified by p2.
* Returns: 0 for permitted, an errno value otherwise
* Locks: Sufficient locks to protect p1->p_ucred and p2->p_ucred must
* be held. Normally, p1 will be curproc, and a lock must be held
* for p2.
* References: p1 and p2 must be valid for the lifetime of the call
*/
int
p_cansee(struct proc *p1, struct proc *p2)
{
/* Wrap cr_cansee() for all functionality. */
return (cr_cansee(p1->p_ucred, p2->p_ucred));
}
/*-
* Determine whether p1 may deliver the specified signal to p2.
* Returns: 0 for permitted, an errno value otherwise
* Locks: Sufficient locks to protect various components of p1 and p2
* must be held. Normally, p1 will be curproc, and a lock must
* be held for p2.
* References: p1 and p2 must be valid for the lifetime of the call
*/
int
p_cansignal(struct proc *p1, struct proc *p2, int signum)
{
int error;
if (p1 == p2)
return (0);
/*
* Jail semantics limit the scope of signalling to p2 in the same
* jail as p1, if p1 is in jail.
*/
if ((error = prison_check(p1->p_ucred, p2->p_ucred)))
return (error);
/*
* UNIX signalling semantics require that processes in the same
* session always be able to deliver SIGCONT to one another,
* overriding the remaining protections.
*/
if (signum == SIGCONT && p1->p_session == p2->p_session)
return (0);
/*
* UNIX signal semantics depend on the status of the P_SUGID
* bit on the target process. If the bit is set, then additional
* restrictions are placed on the set of available signals.
*/
if (p2->p_flag & P_SUGID) {
switch (signum) {
case 0:
case SIGKILL:
case SIGINT:
case SIGTERM:
case SIGSTOP:
case SIGTTIN:
case SIGTTOU:
case SIGTSTP:
case SIGHUP:
case SIGUSR1:
case SIGUSR2:
/*
* Generally, permit job and terminal control
* signals.
*/
break;
default:
/* Not permitted, privilege is required. */
error = suser_xxx(NULL, p1, PRISON_ROOT);
if (error)
return (error);
}
}
/*
* Generally, the target credential's ruid or svuid must match the
* subject credential's ruid or euid.
*/
if (p1->p_ucred->cr_ruid != p2->p_ucred->cr_ruid &&
p1->p_ucred->cr_ruid != p2->p_ucred->cr_svuid &&
p1->p_ucred->cr_uid != p2->p_ucred->cr_ruid &&
p1->p_ucred->cr_uid != p2->p_ucred->cr_svuid) {
/* Not permitted, try privilege. */
error = suser_xxx(NULL, p1, PRISON_ROOT);
if (error)
return (error);
}
return (0);
}
/*-
* Determine whether p1 may reschedule p2.
* Returns: 0 for permitted, an errno value otherwise
* Locks: Sufficient locks to protect various components of p1 and p2
* must be held. Normally, p1 will be curproc, and a lock must
* be held for p2.
* References: p1 and p2 must be valid for the lifetime of the call
*/
int
p_cansched(struct proc *p1, struct proc *p2)
{
int error;
if (p1 == p2)
return (0);
if ((error = prison_check(p1->p_ucred, p2->p_ucred)))
return (error);
if (p1->p_ucred->cr_ruid == p2->p_ucred->cr_ruid)
return (0);
if (p1->p_ucred->cr_uid == p2->p_ucred->cr_ruid)
return (0);
if (suser_xxx(0, p1, PRISON_ROOT) == 0)
return (0);
#ifdef CAPABILITIES
if (!cap_check(NULL, p1, CAP_SYS_NICE, PRISON_ROOT))
return (0);
#endif
return (EPERM);
}
/*
* The 'unprivileged_proc_debug' flag may be used to disable a variety of
* unprivileged inter-process debugging services, including some procfs
* functionality, ptrace(), and ktrace(). In the past, inter-process
* debugging has been involved in a variety of security problems, and sites
* not requiring the service might choose to disable it when hardening
* systems.
*
* XXX: Should modifying and reading this variable require locking?
* XXX: data declarations should be together near the beginning of the file.
*/
static int unprivileged_proc_debug = 1;
SYSCTL_INT(_kern_security_bsd, OID_AUTO, unprivileged_proc_debug, CTLFLAG_RW,
&unprivileged_proc_debug, 0,
"Unprivileged processes may use process debugging facilities");
/*-
* Determine whether p1 may debug p2.
* Returns: 0 for permitted, an errno value otherwise
* Locks: Sufficient locks to protect various components of p1 and p2
* must be held. Normally, p1 will be curproc, and a lock must
* be held for p2.
* References: p1 and p2 must be valid for the lifetime of the call
*/
int
p_candebug(struct proc *p1, struct proc *p2)
{
int credentialchanged, error, grpsubset, i, uidsubset;
if (!unprivileged_proc_debug) {
error = suser_xxx(NULL, p1, PRISON_ROOT);
if (error)
return (error);
}
if (p1 == p2)
return (0);
if ((error = prison_check(p1->p_ucred, p2->p_ucred)))
return (error);
/*
* Is p2's group set a subset of p1's effective group set? This
* includes p2's egid, group access list, rgid, and svgid.
*/
grpsubset = 1;
for (i = 0; i < p2->p_ucred->cr_ngroups; i++) {
if (!groupmember(p2->p_ucred->cr_groups[i], p1->p_ucred)) {
grpsubset = 0;
break;
}
}
grpsubset = grpsubset &&
groupmember(p2->p_ucred->cr_rgid, p1->p_ucred) &&
groupmember(p2->p_ucred->cr_svgid, p1->p_ucred);
/*
* Are the uids present in p2's credential equal to p1's
* effective uid? This includes p2's euid, svuid, and ruid.
*/
uidsubset = (p1->p_ucred->cr_uid == p2->p_ucred->cr_uid &&
p1->p_ucred->cr_uid == p2->p_ucred->cr_svuid &&
p1->p_ucred->cr_uid == p2->p_ucred->cr_ruid);
/*
* Has the credential of the process changed since the last exec()?
*/
credentialchanged = (p2->p_flag & P_SUGID);
/*
* If p2's gids aren't a subset, or the uids aren't a subset,
* or the credential has changed, require appropriate privilege
* for p1 to debug p2. For POSIX.1e capabilities, this will
* require CAP_SYS_PTRACE.
*/
if (!grpsubset || !uidsubset || credentialchanged) {
error = suser_xxx(NULL, p1, PRISON_ROOT);
if (error)
return (error);
}
/* Can't trace init when securelevel > 0. */
if (p2 == initproc) {
error = securelevel_gt(p1->p_ucred, 0);
if (error)
return (error);
}
/*
* Can't trace a process that's currently exec'ing.
* XXX: Note, this is not a security policy decision, it's a
* basic correctness/functionality decision. Therefore, this check
* should be moved to the caller's of p_candebug().
*/
if ((p2->p_flag & P_INEXEC) != 0)
return (EAGAIN);
return (0);
}
/*
* Allocate a zeroed cred structure.
*/
struct ucred *
crget()
{
register struct ucred *cr;
MALLOC(cr, struct ucred *, sizeof(*cr), M_CRED, M_WAITOK | M_ZERO);
cr->cr_ref = 1;
mtx_init(&cr->cr_mtx, "ucred", MTX_DEF);
return (cr);
}
/*
* Claim another reference to a ucred structure.
*/
struct ucred *
crhold(cr)
struct ucred *cr;
{
mtx_lock(&cr->cr_mtx);
cr->cr_ref++;
mtx_unlock(&cr->cr_mtx);
return (cr);
}
/*
* Free a cred structure.
* Throws away space when ref count gets to 0.
*/
void
crfree(cr)
struct ucred *cr;
{
mtx_lock(&cr->cr_mtx);
KASSERT(cr->cr_ref > 0, ("bad ucred refcount: %d", cr->cr_ref));
if (--cr->cr_ref == 0) {
mtx_destroy(&cr->cr_mtx);
/*
* Some callers of crget(), such as nfs_statfs(),
* allocate a temporary credential, but don't
* allocate a uidinfo structure.
*/
if (cr->cr_uidinfo != NULL)
uifree(cr->cr_uidinfo);
if (cr->cr_ruidinfo != NULL)
uifree(cr->cr_ruidinfo);
/*
* Free a prison, if any.
*/
if (jailed(cr))
prison_free(cr->cr_prison);
FREE((caddr_t)cr, M_CRED);
} else
mtx_unlock(&cr->cr_mtx);
}
/*
* Check to see if this ucred is shared.
*/
int
crshared(cr)
struct ucred *cr;
{
int shared;
mtx_lock(&cr->cr_mtx);
shared = (cr->cr_ref > 1);
mtx_unlock(&cr->cr_mtx);
return (shared);
}
/*
* Copy a ucred's contents from a template. Does not block.
*/
void
crcopy(dest, src)
struct ucred *dest, *src;
{
KASSERT(crshared(dest) == 0, ("crcopy of shared ucred"));
bcopy(&src->cr_startcopy, &dest->cr_startcopy,
(unsigned)((caddr_t)&src->cr_endcopy -
(caddr_t)&src->cr_startcopy));
uihold(dest->cr_uidinfo);
uihold(dest->cr_ruidinfo);
if (jailed(dest))
prison_hold(dest->cr_prison);
}
/*
* Dup cred struct to a new held one.
*/
struct ucred *
crdup(cr)
struct ucred *cr;
{
struct ucred *newcr;
newcr = crget();
crcopy(newcr, cr);
return (newcr);
}
/*
* Get login name, if available.
*/
#ifndef _SYS_SYSPROTO_H_
struct getlogin_args {
char *namebuf;
u_int namelen;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
getlogin(td, uap)
struct thread *td;
struct getlogin_args *uap;
{
int error;
struct proc *p = td->td_proc;
mtx_lock(&Giant);
if (uap->namelen > MAXLOGNAME)
uap->namelen = MAXLOGNAME;
error = copyout((caddr_t) p->p_pgrp->pg_session->s_login,
(caddr_t) uap->namebuf, uap->namelen);
mtx_unlock(&Giant);
return(error);
}
/*
* Set login name.
*/
#ifndef _SYS_SYSPROTO_H_
struct setlogin_args {
char *namebuf;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
setlogin(td, uap)
struct thread *td;
struct setlogin_args *uap;
{
struct proc *p = td->td_proc;
int error;
char logintmp[MAXLOGNAME];
mtx_lock(&Giant);
if ((error = suser_xxx(0, p, PRISON_ROOT)) != 0)
goto done2;
error = copyinstr((caddr_t) uap->namebuf, (caddr_t) logintmp,
sizeof(logintmp), (size_t *)0);
if (error == ENAMETOOLONG)
error = EINVAL;
else if (!error)
(void)memcpy(p->p_pgrp->pg_session->s_login, logintmp,
sizeof(logintmp));
done2:
mtx_unlock(&Giant);
return (error);
}
void
setsugid(p)
struct proc *p;
{
p->p_flag |= P_SUGID;
if (!(p->p_pfsflags & PF_ISUGID))
p->p_stops = 0;
}
/*-
* Change a process's effective uid.
* Side effects: newcred->cr_uid and newcred->cr_uidinfo will be modified.
* References: newcred must be an exclusive credential reference for the
* duration of the call.
*/
void
change_euid(newcred, euid)
struct ucred *newcred;
uid_t euid;
{
newcred->cr_uid = euid;
uifree(newcred->cr_uidinfo);
newcred->cr_uidinfo = uifind(euid);
}
/*-
* Change a process's effective gid.
* Side effects: newcred->cr_gid will be modified.
* References: newcred must be an exclusive credential reference for the
* duration of the call.
*/
void
change_egid(newcred, egid)
struct ucred *newcred;
gid_t egid;
{
newcred->cr_groups[0] = egid;
}
/*-
* Change a process's real uid.
* Side effects: newcred->cr_ruid will be updated, newcred->cr_ruidinfo
* will be updated, and the old and new cr_ruidinfo proc
* counts will be updated.
* References: newcred must be an exclusive credential reference for the
* duration of the call.
*/
void
change_ruid(newcred, ruid)
struct ucred *newcred;
uid_t ruid;
{
(void)chgproccnt(newcred->cr_ruidinfo, -1, 0);
newcred->cr_ruid = ruid;
uifree(newcred->cr_ruidinfo);
newcred->cr_ruidinfo = uifind(ruid);
(void)chgproccnt(newcred->cr_ruidinfo, 1, 0);
}
/*-
* Change a process's real gid.
* Side effects: newcred->cr_rgid will be updated.
* References: newcred must be an exclusive credential reference for the
* duration of the call.
*/
void
change_rgid(newcred, rgid)
struct ucred *newcred;
gid_t rgid;
{
newcred->cr_rgid = rgid;
}
/*-
* Change a process's saved uid.
* Side effects: newcred->cr_svuid will be updated.
* References: newcred must be an exclusive credential reference for the
* duration of the call.
*/
void
change_svuid(newcred, svuid)
struct ucred *newcred;
uid_t svuid;
{
newcred->cr_svuid = svuid;
}
/*-
* Change a process's saved gid.
* Side effects: newcred->cr_svgid will be updated.
* References: newcred must be an exclusive credential reference for the
* duration of the call.
*/
void
change_svgid(newcred, svgid)
struct ucred *newcred;
gid_t svgid;
{
newcred->cr_svgid = svgid;
}