1181 lines
27 KiB
C
1181 lines
27 KiB
C
/* $OpenBSD: kern_prot.c,v 1.82 2023/01/09 02:12:13 guenther Exp $ */
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/* $NetBSD: kern_prot.c,v 1.33 1996/02/09 18:59:42 christos Exp $ */
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/*
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* Copyright (c) 1982, 1986, 1989, 1990, 1991, 1993
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* The Regents of the University of California. All rights reserved.
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* (c) UNIX System Laboratories, Inc.
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* All or some portions of this file are derived from material licensed
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* to the University of California by American Telephone and Telegraph
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* Co. or Unix System Laboratories, Inc. and are reproduced herein with
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* the permission of UNIX System Laboratories, Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)kern_prot.c 8.6 (Berkeley) 1/21/94
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*/
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/*
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* System calls related to processes and protection
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*/
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#include <sys/param.h>
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#include <sys/atomic.h>
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#include <sys/systm.h>
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#include <sys/ucred.h>
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#include <sys/proc.h>
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#include <sys/filedesc.h>
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#include <sys/pool.h>
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#include <sys/mount.h>
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#include <sys/syscallargs.h>
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#include <machine/tcb.h>
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inline void
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crset(struct ucred *newcr, const struct ucred *cr)
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{
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KASSERT(cr->cr_refcnt.r_refs > 0);
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memcpy(
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(char *)newcr + offsetof(struct ucred, cr_startcopy),
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(const char *)cr + offsetof(struct ucred, cr_startcopy),
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sizeof(*cr) - offsetof(struct ucred, cr_startcopy));
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}
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int
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sys_getpid(struct proc *p, void *v, register_t *retval)
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{
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*retval = p->p_p->ps_pid;
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return (0);
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}
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int
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sys_getthrid(struct proc *p, void *v, register_t *retval)
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{
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*retval = p->p_tid + THREAD_PID_OFFSET;
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return (0);
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}
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int
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sys_getppid(struct proc *p, void *v, register_t *retval)
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{
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*retval = p->p_p->ps_ppid;
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return (0);
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}
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/* Get process group ID; note that POSIX getpgrp takes no parameter */
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int
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sys_getpgrp(struct proc *p, void *v, register_t *retval)
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{
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*retval = p->p_p->ps_pgrp->pg_id;
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return (0);
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}
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/*
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* SysVR.4 compatible getpgid()
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*/
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int
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sys_getpgid(struct proc *curp, void *v, register_t *retval)
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{
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struct sys_getpgid_args /* {
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syscallarg(pid_t) pid;
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} */ *uap = v;
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struct process *targpr = curp->p_p;
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if (SCARG(uap, pid) == 0 || SCARG(uap, pid) == targpr->ps_pid)
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goto found;
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if ((targpr = prfind(SCARG(uap, pid))) == NULL)
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return (ESRCH);
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if (targpr->ps_session != curp->p_p->ps_session)
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return (EPERM);
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found:
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*retval = targpr->ps_pgid;
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return (0);
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}
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int
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sys_getsid(struct proc *curp, void *v, register_t *retval)
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{
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struct sys_getsid_args /* {
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syscallarg(pid_t) pid;
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} */ *uap = v;
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struct process *targpr = curp->p_p;
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if (SCARG(uap, pid) == 0 || SCARG(uap, pid) == targpr->ps_pid)
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goto found;
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if ((targpr = prfind(SCARG(uap, pid))) == NULL)
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return (ESRCH);
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if (targpr->ps_session != curp->p_p->ps_session)
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return (EPERM);
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found:
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/* Skip exiting processes */
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if (targpr->ps_pgrp->pg_session->s_leader == NULL)
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return (ESRCH);
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*retval = targpr->ps_pgrp->pg_session->s_leader->ps_pid;
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return (0);
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}
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int
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sys_getuid(struct proc *p, void *v, register_t *retval)
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{
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*retval = p->p_ucred->cr_ruid;
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return (0);
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}
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int
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sys_geteuid(struct proc *p, void *v, register_t *retval)
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{
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*retval = p->p_ucred->cr_uid;
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return (0);
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}
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int
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sys_issetugid(struct proc *p, void *v, register_t *retval)
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{
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if (p->p_p->ps_flags & PS_SUGIDEXEC)
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*retval = 1;
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else
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*retval = 0;
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return (0);
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}
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int
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sys_getgid(struct proc *p, void *v, register_t *retval)
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{
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*retval = p->p_ucred->cr_rgid;
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return (0);
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}
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/*
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* Get effective group ID. The "egid" is groups[0], and could be obtained
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* via getgroups. This syscall exists because it is somewhat painful to do
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* correctly in a library function.
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*/
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int
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sys_getegid(struct proc *p, void *v, register_t *retval)
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{
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*retval = p->p_ucred->cr_gid;
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return (0);
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}
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int
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sys_getgroups(struct proc *p, void *v, register_t *retval)
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{
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struct sys_getgroups_args /* {
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syscallarg(int) gidsetsize;
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syscallarg(gid_t *) gidset;
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} */ *uap = v;
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struct ucred *uc = p->p_ucred;
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int ngrp;
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int error;
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if ((ngrp = SCARG(uap, gidsetsize)) == 0) {
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*retval = uc->cr_ngroups;
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return (0);
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}
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if (ngrp < uc->cr_ngroups)
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return (EINVAL);
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ngrp = uc->cr_ngroups;
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error = copyout(uc->cr_groups, SCARG(uap, gidset),
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ngrp * sizeof(gid_t));
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if (error)
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return (error);
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*retval = ngrp;
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return (0);
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}
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int
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sys_setsid(struct proc *p, void *v, register_t *retval)
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{
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struct session *newsess;
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struct pgrp *newpgrp;
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struct process *pr = p->p_p;
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pid_t pid = pr->ps_pid;
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newsess = pool_get(&session_pool, PR_WAITOK);
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newpgrp = pool_get(&pgrp_pool, PR_WAITOK);
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if (pr->ps_pgid == pid || pgfind(pid) != NULL) {
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pool_put(&pgrp_pool, newpgrp);
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pool_put(&session_pool, newsess);
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return (EPERM);
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} else {
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enternewpgrp(pr, newpgrp, newsess);
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*retval = pid;
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return (0);
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}
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}
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/*
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* set process group (setpgid/old setpgrp)
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*
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* caller does setpgid(targpid, targpgid)
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*
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* pid must be caller or child of caller (ESRCH)
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* if a child
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* pid must be in same session (EPERM)
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* pid can't have done an exec (EACCES)
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* if pgid != pid
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* there must exist some pid in same session having pgid (EPERM)
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* pid must not be session leader (EPERM)
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*/
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int
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sys_setpgid(struct proc *curp, void *v, register_t *retval)
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{
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struct sys_setpgid_args /* {
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syscallarg(pid_t) pid;
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syscallarg(pid_t) pgid;
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} */ *uap = v;
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struct process *curpr = curp->p_p;
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struct process *targpr; /* target process */
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struct pgrp *pgrp, *newpgrp; /* target pgrp */
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pid_t pid, pgid;
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int error;
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pid = SCARG(uap, pid);
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pgid = SCARG(uap, pgid);
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if (pgid < 0)
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return (EINVAL);
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newpgrp = pool_get(&pgrp_pool, PR_WAITOK);
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if (pid != 0 && pid != curpr->ps_pid) {
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if ((targpr = prfind(pid)) == NULL ||
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!inferior(targpr, curpr)) {
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error = ESRCH;
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goto out;
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}
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if (targpr->ps_session != curpr->ps_session) {
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error = EPERM;
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goto out;
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}
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if (targpr->ps_flags & PS_EXEC) {
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error = EACCES;
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goto out;
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}
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} else
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targpr = curpr;
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if (SESS_LEADER(targpr)) {
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error = EPERM;
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goto out;
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}
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if (pgid == 0)
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pgid = targpr->ps_pid;
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error = 0;
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if ((pgrp = pgfind(pgid)) == NULL) {
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/* can only create a new process group with pgid == pid */
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if (pgid != targpr->ps_pid)
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error = EPERM;
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else {
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enternewpgrp(targpr, newpgrp, NULL);
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newpgrp = NULL;
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}
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} else if (pgrp != targpr->ps_pgrp) { /* anything to do? */
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if (pgid != targpr->ps_pid &&
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pgrp->pg_session != curpr->ps_session)
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error = EPERM;
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else
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enterthispgrp(targpr, pgrp);
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}
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out:
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if (newpgrp != NULL)
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pool_put(&pgrp_pool, newpgrp);
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return (error);
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}
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int
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sys_getresuid(struct proc *p, void *v, register_t *retval)
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{
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struct sys_getresuid_args /* {
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syscallarg(uid_t *) ruid;
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syscallarg(uid_t *) euid;
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syscallarg(uid_t *) suid;
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} */ *uap = v;
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struct ucred *uc = p->p_ucred;
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uid_t *ruid, *euid, *suid;
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int error1 = 0, error2 = 0, error3 = 0;
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ruid = SCARG(uap, ruid);
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euid = SCARG(uap, euid);
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suid = SCARG(uap, suid);
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if (ruid != NULL)
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error1 = copyout(&uc->cr_ruid, ruid, sizeof(*ruid));
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if (euid != NULL)
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error2 = copyout(&uc->cr_uid, euid, sizeof(*euid));
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if (suid != NULL)
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error3 = copyout(&uc->cr_svuid, suid, sizeof(*suid));
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return (error1 ? error1 : error2 ? error2 : error3);
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}
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int
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sys_setresuid(struct proc *p, void *v, register_t *retval)
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{
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struct sys_setresuid_args /* {
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syscallarg(uid_t) ruid;
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syscallarg(uid_t) euid;
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syscallarg(uid_t) suid;
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} */ *uap = v;
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struct process *pr = p->p_p;
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struct ucred *pruc, *newcred, *uc = p->p_ucred;
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uid_t ruid, euid, suid;
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int error;
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ruid = SCARG(uap, ruid);
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euid = SCARG(uap, euid);
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suid = SCARG(uap, suid);
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/*
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* make permission checks against the thread's ucred,
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* but the actual changes will be to the process's ucred
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*/
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pruc = pr->ps_ucred;
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if ((ruid == (uid_t)-1 || ruid == pruc->cr_ruid) &&
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(euid == (uid_t)-1 || euid == pruc->cr_uid) &&
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(suid == (uid_t)-1 || suid == pruc->cr_svuid))
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return (0); /* no change */
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/*
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* Any of the real, effective, and saved uids may be changed
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* to the current value of one of the three (root is not limited).
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*/
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if (ruid != (uid_t)-1 &&
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ruid != uc->cr_ruid &&
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ruid != uc->cr_uid &&
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ruid != uc->cr_svuid &&
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(error = suser(p)))
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return (error);
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if (euid != (uid_t)-1 &&
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euid != uc->cr_ruid &&
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euid != uc->cr_uid &&
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euid != uc->cr_svuid &&
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(error = suser(p)))
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return (error);
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if (suid != (uid_t)-1 &&
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suid != uc->cr_ruid &&
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suid != uc->cr_uid &&
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suid != uc->cr_svuid &&
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(error = suser(p)))
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return (error);
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/*
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* Copy credentials so other references do not see our changes.
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* ps_ucred may change during the crget().
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*/
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newcred = crget();
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pruc = pr->ps_ucred;
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crset(newcred, pruc);
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/*
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* Note that unlike the other set*uid() calls, each
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* uid type is set independently of the others.
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*/
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if (ruid != (uid_t)-1)
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newcred->cr_ruid = ruid;
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if (euid != (uid_t)-1)
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newcred->cr_uid = euid;
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if (suid != (uid_t)-1)
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newcred->cr_svuid = suid;
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pr->ps_ucred = newcred;
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atomic_setbits_int(&p->p_p->ps_flags, PS_SUGID);
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/* now that we can sleep, transfer proc count to new user */
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if (ruid != (uid_t)-1 && ruid != pruc->cr_ruid) {
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chgproccnt(pruc->cr_ruid, -1);
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chgproccnt(ruid, 1);
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}
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crfree(pruc);
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return (0);
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}
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int
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sys_getresgid(struct proc *p, void *v, register_t *retval)
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{
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struct sys_getresgid_args /* {
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syscallarg(gid_t *) rgid;
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syscallarg(gid_t *) egid;
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syscallarg(gid_t *) sgid;
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} */ *uap = v;
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struct ucred *uc = p->p_ucred;
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gid_t *rgid, *egid, *sgid;
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int error1 = 0, error2 = 0, error3 = 0;
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rgid = SCARG(uap, rgid);
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egid = SCARG(uap, egid);
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sgid = SCARG(uap, sgid);
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if (rgid != NULL)
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error1 = copyout(&uc->cr_rgid, rgid, sizeof(*rgid));
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if (egid != NULL)
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error2 = copyout(&uc->cr_gid, egid, sizeof(*egid));
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if (sgid != NULL)
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error3 = copyout(&uc->cr_svgid, sgid, sizeof(*sgid));
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return (error1 ? error1 : error2 ? error2 : error3);
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}
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|
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int
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sys_setresgid(struct proc *p, void *v, register_t *retval)
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{
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struct sys_setresgid_args /* {
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syscallarg(gid_t) rgid;
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syscallarg(gid_t) egid;
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syscallarg(gid_t) sgid;
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} */ *uap = v;
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struct process *pr = p->p_p;
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struct ucred *pruc, *newcred, *uc = p->p_ucred;
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gid_t rgid, egid, sgid;
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int error;
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rgid = SCARG(uap, rgid);
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egid = SCARG(uap, egid);
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sgid = SCARG(uap, sgid);
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|
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/*
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* make permission checks against the thread's ucred,
|
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* but the actual changes will be to the process's ucred
|
|
*/
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pruc = pr->ps_ucred;
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if ((rgid == (gid_t)-1 || rgid == pruc->cr_rgid) &&
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(egid == (gid_t)-1 || egid == pruc->cr_gid) &&
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(sgid == (gid_t)-1 || sgid == pruc->cr_svgid))
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return (0); /* no change */
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|
|
|
/*
|
|
* Any of the real, effective, and saved gids may be changed
|
|
* to the current value of one of the three (root is not limited).
|
|
*/
|
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if (rgid != (gid_t)-1 &&
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rgid != uc->cr_rgid &&
|
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rgid != uc->cr_gid &&
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rgid != uc->cr_svgid &&
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(error = suser(p)))
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return (error);
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|
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if (egid != (gid_t)-1 &&
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egid != uc->cr_rgid &&
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egid != uc->cr_gid &&
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egid != uc->cr_svgid &&
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(error = suser(p)))
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return (error);
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|
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if (sgid != (gid_t)-1 &&
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sgid != uc->cr_rgid &&
|
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sgid != uc->cr_gid &&
|
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sgid != uc->cr_svgid &&
|
|
(error = suser(p)))
|
|
return (error);
|
|
|
|
/*
|
|
* Copy credentials so other references do not see our changes.
|
|
* ps_ucred may change during the crget().
|
|
*/
|
|
newcred = crget();
|
|
pruc = pr->ps_ucred;
|
|
crset(newcred, pruc);
|
|
|
|
/*
|
|
* Note that unlike the other set*gid() calls, each
|
|
* gid type is set independently of the others.
|
|
*/
|
|
if (rgid != (gid_t)-1)
|
|
newcred->cr_rgid = rgid;
|
|
if (egid != (gid_t)-1)
|
|
newcred->cr_gid = egid;
|
|
if (sgid != (gid_t)-1)
|
|
newcred->cr_svgid = sgid;
|
|
pr->ps_ucred = newcred;
|
|
atomic_setbits_int(&p->p_p->ps_flags, PS_SUGID);
|
|
crfree(pruc);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
sys_setregid(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys_setregid_args /* {
|
|
syscallarg(gid_t) rgid;
|
|
syscallarg(gid_t) egid;
|
|
} */ *uap = v;
|
|
struct process *pr = p->p_p;
|
|
struct ucred *pruc, *newcred, *uc = p->p_ucred;
|
|
gid_t rgid, egid;
|
|
int error;
|
|
|
|
rgid = SCARG(uap, rgid);
|
|
egid = SCARG(uap, egid);
|
|
|
|
/*
|
|
* make permission checks against the thread's ucred,
|
|
* but the actual changes will be to the process's ucred
|
|
*
|
|
* The saved gid check here is complicated: we reset the
|
|
* saved gid to the real gid if the real gid is specified
|
|
* *and* either it's changing _or_ the saved gid won't equal
|
|
* the effective gid. So, the svgid *won't* change when
|
|
* the rgid isn't specified or when the rgid isn't changing
|
|
* and the svgid equals the requested egid.
|
|
*/
|
|
pruc = pr->ps_ucred;
|
|
if ((rgid == (gid_t)-1 || rgid == pruc->cr_rgid) &&
|
|
(egid == (gid_t)-1 || egid == pruc->cr_gid) &&
|
|
(rgid == (gid_t)-1 || (rgid == pruc->cr_rgid &&
|
|
pruc->cr_svgid == (egid != (gid_t)-1 ? egid : pruc->cr_gid))))
|
|
return (0); /* no change */
|
|
|
|
/*
|
|
* Any of the real, effective, and saved gids may be changed
|
|
* to the current value of one of the three (root is not limited).
|
|
*/
|
|
if (rgid != (gid_t)-1 &&
|
|
rgid != uc->cr_rgid &&
|
|
rgid != uc->cr_gid &&
|
|
rgid != uc->cr_svgid &&
|
|
(error = suser(p)))
|
|
return (error);
|
|
|
|
if (egid != (gid_t)-1 &&
|
|
egid != uc->cr_rgid &&
|
|
egid != uc->cr_gid &&
|
|
egid != uc->cr_svgid &&
|
|
(error = suser(p)))
|
|
return (error);
|
|
|
|
/*
|
|
* Copy credentials so other references do not see our changes.
|
|
* ps_ucred may change during the crget().
|
|
*/
|
|
newcred = crget();
|
|
pruc = pr->ps_ucred;
|
|
crset(newcred, pruc);
|
|
|
|
if (rgid != (gid_t)-1)
|
|
newcred->cr_rgid = rgid;
|
|
if (egid != (gid_t)-1)
|
|
newcred->cr_gid = egid;
|
|
|
|
/*
|
|
* The saved gid presents a bit of a dilemma, as it did not
|
|
* exist when setregid(2) was conceived. We only set the saved
|
|
* gid when the real gid is specified and either its value would
|
|
* change, or where the saved and effective gids are different.
|
|
*/
|
|
if (rgid != (gid_t)-1 && (rgid != pruc->cr_rgid ||
|
|
pruc->cr_svgid != (egid != (gid_t)-1 ? egid : pruc->cr_gid)))
|
|
newcred->cr_svgid = rgid;
|
|
pr->ps_ucred = newcred;
|
|
atomic_setbits_int(&p->p_p->ps_flags, PS_SUGID);
|
|
crfree(pruc);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
sys_setreuid(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys_setreuid_args /* {
|
|
syscallarg(uid_t) ruid;
|
|
syscallarg(uid_t) euid;
|
|
} */ *uap = v;
|
|
struct process *pr = p->p_p;
|
|
struct ucred *pruc, *newcred, *uc = p->p_ucred;
|
|
uid_t ruid, euid;
|
|
int error;
|
|
|
|
ruid = SCARG(uap, ruid);
|
|
euid = SCARG(uap, euid);
|
|
|
|
/*
|
|
* make permission checks against the thread's ucred,
|
|
* but the actual changes will be to the process's ucred
|
|
*
|
|
* The saved uid check here is complicated: we reset the
|
|
* saved uid to the real uid if the real uid is specified
|
|
* *and* either it's changing _or_ the saved uid won't equal
|
|
* the effective uid. So, the svuid *won't* change when
|
|
* the ruid isn't specified or when the ruid isn't changing
|
|
* and the svuid equals the requested euid.
|
|
*/
|
|
pruc = pr->ps_ucred;
|
|
if ((ruid == (uid_t)-1 || ruid == pruc->cr_ruid) &&
|
|
(euid == (uid_t)-1 || euid == pruc->cr_uid) &&
|
|
(ruid == (uid_t)-1 || (ruid == pruc->cr_ruid &&
|
|
pruc->cr_svuid == (euid != (uid_t)-1 ? euid : pruc->cr_uid))))
|
|
return (0); /* no change */
|
|
|
|
/*
|
|
* Any of the real, effective, and saved uids may be changed
|
|
* to the current value of one of the three (root is not limited).
|
|
*/
|
|
if (ruid != (uid_t)-1 &&
|
|
ruid != uc->cr_ruid &&
|
|
ruid != uc->cr_uid &&
|
|
ruid != uc->cr_svuid &&
|
|
(error = suser(p)))
|
|
return (error);
|
|
|
|
if (euid != (uid_t)-1 &&
|
|
euid != uc->cr_ruid &&
|
|
euid != uc->cr_uid &&
|
|
euid != uc->cr_svuid &&
|
|
(error = suser(p)))
|
|
return (error);
|
|
|
|
/*
|
|
* Copy credentials so other references do not see our changes.
|
|
* ps_ucred may change during the crget().
|
|
*/
|
|
newcred = crget();
|
|
pruc = pr->ps_ucred;
|
|
crset(newcred, pruc);
|
|
|
|
if (ruid != (uid_t)-1)
|
|
newcred->cr_ruid = ruid;
|
|
if (euid != (uid_t)-1)
|
|
newcred->cr_uid = euid;
|
|
|
|
/*
|
|
* The saved uid presents a bit of a dilemma, as it did not
|
|
* exist when setreuid(2) was conceived. We only set the saved
|
|
* uid when the real uid is specified and either its value would
|
|
* change, or where the saved and effective uids are different.
|
|
*/
|
|
if (ruid != (uid_t)-1 && (ruid != pruc->cr_ruid ||
|
|
pruc->cr_svuid != (euid != (uid_t)-1 ? euid : pruc->cr_uid)))
|
|
newcred->cr_svuid = ruid;
|
|
pr->ps_ucred = newcred;
|
|
atomic_setbits_int(&p->p_p->ps_flags, PS_SUGID);
|
|
|
|
/* now that we can sleep, transfer proc count to new user */
|
|
if (ruid != (uid_t)-1 && ruid != pruc->cr_ruid) {
|
|
chgproccnt(pruc->cr_ruid, -1);
|
|
chgproccnt(ruid, 1);
|
|
}
|
|
crfree(pruc);
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
sys_setuid(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys_setuid_args /* {
|
|
syscallarg(uid_t) uid;
|
|
} */ *uap = v;
|
|
struct process *pr = p->p_p;
|
|
struct ucred *pruc, *newcred, *uc = p->p_ucred;
|
|
uid_t uid;
|
|
int did_real, error;
|
|
|
|
uid = SCARG(uap, uid);
|
|
|
|
pruc = pr->ps_ucred;
|
|
if (pruc->cr_uid == uid &&
|
|
pruc->cr_ruid == uid &&
|
|
pruc->cr_svuid == uid)
|
|
return (0);
|
|
|
|
if (uid != uc->cr_ruid &&
|
|
uid != uc->cr_svuid &&
|
|
uid != uc->cr_uid &&
|
|
(error = suser(p)))
|
|
return (error);
|
|
|
|
/*
|
|
* Copy credentials so other references do not see our changes.
|
|
* ps_ucred may change during the crget().
|
|
*/
|
|
newcred = crget();
|
|
pruc = pr->ps_ucred;
|
|
crset(newcred, pruc);
|
|
|
|
/*
|
|
* Everything's okay, do it.
|
|
*/
|
|
if (uid == pruc->cr_uid || suser(p) == 0) {
|
|
did_real = 1;
|
|
newcred->cr_ruid = uid;
|
|
newcred->cr_svuid = uid;
|
|
} else
|
|
did_real = 0;
|
|
newcred->cr_uid = uid;
|
|
pr->ps_ucred = newcred;
|
|
atomic_setbits_int(&p->p_p->ps_flags, PS_SUGID);
|
|
|
|
/*
|
|
* Transfer proc count to new user.
|
|
*/
|
|
if (did_real && uid != pruc->cr_ruid) {
|
|
chgproccnt(pruc->cr_ruid, -1);
|
|
chgproccnt(uid, 1);
|
|
}
|
|
crfree(pruc);
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
sys_seteuid(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys_seteuid_args /* {
|
|
syscallarg(uid_t) euid;
|
|
} */ *uap = v;
|
|
struct process *pr = p->p_p;
|
|
struct ucred *pruc, *newcred, *uc = p->p_ucred;
|
|
uid_t euid;
|
|
int error;
|
|
|
|
euid = SCARG(uap, euid);
|
|
|
|
if (pr->ps_ucred->cr_uid == euid)
|
|
return (0);
|
|
|
|
if (euid != uc->cr_ruid && euid != uc->cr_svuid &&
|
|
(error = suser(p)))
|
|
return (error);
|
|
|
|
/*
|
|
* Copy credentials so other references do not see our changes.
|
|
* ps_ucred may change during the crget().
|
|
*/
|
|
newcred = crget();
|
|
pruc = pr->ps_ucred;
|
|
crset(newcred, pruc);
|
|
newcred->cr_uid = euid;
|
|
pr->ps_ucred = newcred;
|
|
atomic_setbits_int(&p->p_p->ps_flags, PS_SUGID);
|
|
crfree(pruc);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
sys_setgid(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys_setgid_args /* {
|
|
syscallarg(gid_t) gid;
|
|
} */ *uap = v;
|
|
struct process *pr = p->p_p;
|
|
struct ucred *pruc, *newcred, *uc = p->p_ucred;
|
|
gid_t gid;
|
|
int error;
|
|
|
|
gid = SCARG(uap, gid);
|
|
|
|
pruc = pr->ps_ucred;
|
|
if (pruc->cr_gid == gid &&
|
|
pruc->cr_rgid == gid &&
|
|
pruc->cr_svgid == gid)
|
|
return (0);
|
|
|
|
if (gid != uc->cr_rgid &&
|
|
gid != uc->cr_svgid &&
|
|
gid != uc->cr_gid &&
|
|
(error = suser(p)))
|
|
return (error);
|
|
|
|
/*
|
|
* Copy credentials so other references do not see our changes.
|
|
* ps_ucred may change during the crget().
|
|
*/
|
|
newcred = crget();
|
|
pruc = pr->ps_ucred;
|
|
crset(newcred, pruc);
|
|
|
|
if (gid == pruc->cr_gid || suser(p) == 0) {
|
|
newcred->cr_rgid = gid;
|
|
newcred->cr_svgid = gid;
|
|
}
|
|
newcred->cr_gid = gid;
|
|
pr->ps_ucred = newcred;
|
|
atomic_setbits_int(&p->p_p->ps_flags, PS_SUGID);
|
|
crfree(pruc);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
sys_setegid(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys_setegid_args /* {
|
|
syscallarg(gid_t) egid;
|
|
} */ *uap = v;
|
|
struct process *pr = p->p_p;
|
|
struct ucred *pruc, *newcred, *uc = p->p_ucred;
|
|
gid_t egid;
|
|
int error;
|
|
|
|
egid = SCARG(uap, egid);
|
|
|
|
if (pr->ps_ucred->cr_gid == egid)
|
|
return (0);
|
|
|
|
if (egid != uc->cr_rgid && egid != uc->cr_svgid &&
|
|
(error = suser(p)))
|
|
return (error);
|
|
|
|
/*
|
|
* Copy credentials so other references do not see our changes.
|
|
* ps_ucred may change during the crget().
|
|
*/
|
|
newcred = crget();
|
|
pruc = pr->ps_ucred;
|
|
crset(newcred, pruc);
|
|
newcred->cr_gid = egid;
|
|
pr->ps_ucred = newcred;
|
|
atomic_setbits_int(&p->p_p->ps_flags, PS_SUGID);
|
|
crfree(pruc);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
sys_setgroups(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys_setgroups_args /* {
|
|
syscallarg(int) gidsetsize;
|
|
syscallarg(const gid_t *) gidset;
|
|
} */ *uap = v;
|
|
struct process *pr = p->p_p;
|
|
struct ucred *pruc, *newcred;
|
|
gid_t groups[NGROUPS_MAX];
|
|
int ngrp;
|
|
int error;
|
|
|
|
if ((error = suser(p)) != 0)
|
|
return (error);
|
|
ngrp = SCARG(uap, gidsetsize);
|
|
if (ngrp > NGROUPS_MAX || ngrp < 0)
|
|
return (EINVAL);
|
|
error = copyin(SCARG(uap, gidset), groups, ngrp * sizeof(gid_t));
|
|
if (error == 0) {
|
|
newcred = crget();
|
|
pruc = pr->ps_ucred;
|
|
crset(newcred, pruc);
|
|
memcpy(newcred->cr_groups, groups, ngrp * sizeof(gid_t));
|
|
newcred->cr_ngroups = ngrp;
|
|
pr->ps_ucred = newcred;
|
|
atomic_setbits_int(&p->p_p->ps_flags, PS_SUGID);
|
|
crfree(pruc);
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Check if gid is a member of the group set.
|
|
*/
|
|
int
|
|
groupmember(gid_t gid, struct ucred *cred)
|
|
{
|
|
gid_t *gp;
|
|
gid_t *egp;
|
|
|
|
if (cred->cr_gid == gid)
|
|
return (1);
|
|
egp = &(cred->cr_groups[cred->cr_ngroups]);
|
|
for (gp = cred->cr_groups; gp < egp; gp++)
|
|
if (*gp == gid)
|
|
return (1);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Test whether this process has special user powers.
|
|
* Returns 0 or error.
|
|
*/
|
|
int
|
|
suser(struct proc *p)
|
|
{
|
|
struct ucred *cred = p->p_ucred;
|
|
|
|
if (cred->cr_uid == 0)
|
|
return (0);
|
|
return (EPERM);
|
|
}
|
|
|
|
/*
|
|
* replacement for old suser, for callers who don't have a process
|
|
*/
|
|
int
|
|
suser_ucred(struct ucred *cred)
|
|
{
|
|
if (cred->cr_uid == 0)
|
|
return (0);
|
|
return (EPERM);
|
|
}
|
|
|
|
/*
|
|
* Allocate a zeroed cred structure.
|
|
*/
|
|
struct ucred *
|
|
crget(void)
|
|
{
|
|
struct ucred *cr;
|
|
|
|
cr = pool_get(&ucred_pool, PR_WAITOK|PR_ZERO);
|
|
refcnt_init(&cr->cr_refcnt);
|
|
return (cr);
|
|
}
|
|
|
|
/*
|
|
* Increment the reference count of a cred structure.
|
|
* Returns the passed structure.
|
|
*/
|
|
struct ucred *
|
|
crhold(struct ucred *cr)
|
|
{
|
|
refcnt_take(&cr->cr_refcnt);
|
|
return (cr);
|
|
}
|
|
|
|
/*
|
|
* Free a cred structure.
|
|
* Throws away space when ref count gets to 0.
|
|
*/
|
|
void
|
|
crfree(struct ucred *cr)
|
|
{
|
|
if (refcnt_rele(&cr->cr_refcnt))
|
|
pool_put(&ucred_pool, cr);
|
|
}
|
|
|
|
/*
|
|
* Copy cred structure to a new one and free the old one.
|
|
*/
|
|
struct ucred *
|
|
crcopy(struct ucred *cr)
|
|
{
|
|
struct ucred *newcr;
|
|
|
|
if (!refcnt_shared(&cr->cr_refcnt))
|
|
return (cr);
|
|
newcr = crget();
|
|
*newcr = *cr;
|
|
crfree(cr);
|
|
refcnt_init(&newcr->cr_refcnt);
|
|
return (newcr);
|
|
}
|
|
|
|
/*
|
|
* Dup cred struct to a new held one.
|
|
*/
|
|
struct ucred *
|
|
crdup(struct ucred *cr)
|
|
{
|
|
struct ucred *newcr;
|
|
|
|
newcr = crget();
|
|
*newcr = *cr;
|
|
refcnt_init(&newcr->cr_refcnt);
|
|
return (newcr);
|
|
}
|
|
|
|
/*
|
|
* Convert the userspace xucred to a kernel ucred
|
|
*/
|
|
int
|
|
crfromxucred(struct ucred *cr, const struct xucred *xcr)
|
|
{
|
|
if (xcr->cr_ngroups < 0 || xcr->cr_ngroups > NGROUPS_MAX)
|
|
return (EINVAL);
|
|
refcnt_init(&cr->cr_refcnt);
|
|
cr->cr_uid = xcr->cr_uid;
|
|
cr->cr_gid = xcr->cr_gid;
|
|
cr->cr_ngroups = xcr->cr_ngroups;
|
|
memcpy(cr->cr_groups, xcr->cr_groups,
|
|
sizeof(cr->cr_groups[0]) * xcr->cr_ngroups);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Get login name, if available.
|
|
*/
|
|
int
|
|
sys_getlogin_r(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys_getlogin_r_args /* {
|
|
syscallarg(char *) namebuf;
|
|
syscallarg(size_t) namelen;
|
|
} */ *uap = v;
|
|
size_t namelen = SCARG(uap, namelen);
|
|
struct session *s = p->p_p->ps_pgrp->pg_session;
|
|
int error;
|
|
|
|
if (namelen > sizeof(s->s_login))
|
|
namelen = sizeof(s->s_login);
|
|
error = copyoutstr(s->s_login, SCARG(uap, namebuf), namelen, NULL);
|
|
if (error == ENAMETOOLONG)
|
|
error = ERANGE;
|
|
*retval = error;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Set login name.
|
|
*/
|
|
int
|
|
sys_setlogin(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys_setlogin_args /* {
|
|
syscallarg(const char *) namebuf;
|
|
} */ *uap = v;
|
|
struct session *s = p->p_p->ps_pgrp->pg_session;
|
|
char buf[sizeof(s->s_login)];
|
|
int error;
|
|
|
|
if ((error = suser(p)) != 0)
|
|
return (error);
|
|
error = copyinstr(SCARG(uap, namebuf), buf, sizeof(buf), NULL);
|
|
if (error == 0)
|
|
strlcpy(s->s_login, buf, sizeof(s->s_login));
|
|
else if (error == ENAMETOOLONG)
|
|
error = EINVAL;
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Check if a process is allowed to raise its privileges.
|
|
*/
|
|
int
|
|
proc_cansugid(struct proc *p)
|
|
{
|
|
/* ptrace(2)d processes shouldn't. */
|
|
if ((p->p_p->ps_flags & PS_TRACED) != 0)
|
|
return (0);
|
|
|
|
/* processes with shared filedescriptors shouldn't. */
|
|
if (p->p_fd->fd_refcnt > 1)
|
|
return (0);
|
|
|
|
/* Allow. */
|
|
return (1);
|
|
}
|
|
|
|
/*
|
|
* Set address of the proc's thread-control-block
|
|
*/
|
|
int
|
|
sys___set_tcb(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
struct sys___set_tcb_args /* {
|
|
syscallarg(void *) tcb;
|
|
} */ *uap = v;
|
|
void *tcb = SCARG(uap, tcb);
|
|
|
|
#ifdef TCB_INVALID
|
|
if (TCB_INVALID(tcb))
|
|
return EINVAL;
|
|
#endif /* TCB_INVALID */
|
|
TCB_SET(p, tcb);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Get address of the proc's thread-control-block
|
|
*/
|
|
int
|
|
sys___get_tcb(struct proc *p, void *v, register_t *retval)
|
|
{
|
|
*retval = (register_t)TCB_GET(p);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
sys_getthrname(struct proc *curp, void *v, register_t *retval)
|
|
{
|
|
struct sys_getthrname_args /* {
|
|
syscallarg(pid_t) tid;
|
|
syscallarg(char *) name;
|
|
syscallarg(size_t) len;
|
|
} */ *uap = v;
|
|
struct proc *p;
|
|
size_t len;
|
|
int tid = SCARG(uap, tid);
|
|
int error;
|
|
|
|
p = tid ? tfind_user(tid, curp->p_p) : curp;
|
|
if (p == NULL)
|
|
return ESRCH;
|
|
|
|
len = SCARG(uap, len);
|
|
if (len > sizeof(p->p_name))
|
|
len = sizeof(p->p_name);
|
|
error = copyoutstr(p->p_name, SCARG(uap, name), len, NULL);
|
|
if (error == ENAMETOOLONG)
|
|
error = ERANGE;
|
|
*retval = error;
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
sys_setthrname(struct proc *curp, void *v, register_t *retval)
|
|
{
|
|
struct sys_setthrname_args /* {
|
|
syscallarg(pid_t) tid;
|
|
syscallarg(const char *) name;
|
|
} */ *uap = v;
|
|
struct proc *p;
|
|
char buf[sizeof p->p_name];
|
|
int tid = SCARG(uap, tid);
|
|
int error;
|
|
|
|
p = tid ? tfind_user(tid, curp->p_p) : curp;
|
|
if (p == NULL)
|
|
return ESRCH;
|
|
|
|
error = copyinstr(SCARG(uap, name), buf, sizeof buf, NULL);
|
|
if (error == 0)
|
|
strlcpy(p->p_name, buf, sizeof(p->p_name));
|
|
else if (error == ENAMETOOLONG)
|
|
error = EINVAL;
|
|
*retval = error;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Refresh the thread's reference to the process's credentials
|
|
*/
|
|
void
|
|
dorefreshcreds(struct process *pr, struct proc *p)
|
|
{
|
|
struct ucred *uc = p->p_ucred;
|
|
|
|
KERNEL_LOCK(); /* XXX should be PROCESS_RLOCK(pr) */
|
|
if (uc != pr->ps_ucred) {
|
|
p->p_ucred = pr->ps_ucred;
|
|
crhold(p->p_ucred);
|
|
crfree(uc);
|
|
}
|
|
KERNEL_UNLOCK();
|
|
}
|