fe8ddb95e0
MAC Framework doesn't require checks in ipcperm() because checks relating to System V IPC will be performed in individual IPC implementations.
122 lines
3.5 KiB
C
122 lines
3.5 KiB
C
/* $NetBSD: sysv_ipc.c,v 1.7 1994/06/29 06:33:11 cgd Exp $ */
|
|
/*
|
|
* Copyright (c) 1994 Herb Peyerl <hpeyerl@novatel.ca>
|
|
* 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 Herb Peyerl.
|
|
* 4. The name of Herb Peyerl may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "opt_sysvipc.h"
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/sem.h>
|
|
#include <sys/shm.h>
|
|
#include <sys/ipc.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/ucred.h>
|
|
|
|
void (*shmfork_hook)(struct proc *, struct proc *) = NULL;
|
|
void (*shmexit_hook)(struct vmspace *) = NULL;
|
|
|
|
/* called from kern_fork.c */
|
|
void
|
|
shmfork(p1, p2)
|
|
struct proc *p1, *p2;
|
|
{
|
|
|
|
if (shmfork_hook != NULL)
|
|
shmfork_hook(p1, p2);
|
|
return;
|
|
}
|
|
|
|
/* called from kern_exit.c */
|
|
void
|
|
shmexit(struct vmspace *vm)
|
|
{
|
|
|
|
if (shmexit_hook != NULL)
|
|
shmexit_hook(vm);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Check for IPC permission.
|
|
*
|
|
* Note: The MAC Framework does not require any modifications to the
|
|
* ipcperm() function, as access control checks are performed throughout the
|
|
* implementation of each primitive. Those entry point calls complement the
|
|
* ipcperm() discertionary checks.
|
|
*/
|
|
int
|
|
ipcperm(td, perm, mode)
|
|
struct thread *td;
|
|
struct ipc_perm *perm;
|
|
int mode;
|
|
{
|
|
struct ucred *cred = td->td_ucred;
|
|
int error;
|
|
|
|
if (cred->cr_uid != perm->cuid && cred->cr_uid != perm->uid) {
|
|
/*
|
|
* For a non-create/owner, we require privilege to
|
|
* modify the object protections. Note: some other
|
|
* implementations permit IPC_M to be delegated to
|
|
* unprivileged non-creator/owner uids/gids.
|
|
*/
|
|
if (mode & IPC_M) {
|
|
error = suser(td);
|
|
if (error)
|
|
return (error);
|
|
}
|
|
/*
|
|
* Try to match against creator/owner group; if not, fall
|
|
* back on other.
|
|
*/
|
|
mode >>= 3;
|
|
if (!groupmember(perm->gid, cred) &&
|
|
!groupmember(perm->cgid, cred))
|
|
mode >>= 3;
|
|
} else {
|
|
/*
|
|
* Always permit the creator/owner to update the object
|
|
* protections regardless of whether the object mode
|
|
* permits it.
|
|
*/
|
|
if (mode & IPC_M)
|
|
return (0);
|
|
}
|
|
|
|
if ((mode & perm->mode) != mode) {
|
|
if (suser(td) != 0)
|
|
return (EACCES);
|
|
}
|
|
return (0);
|
|
}
|