freebsd-dev/sys/kern/sysv_ipc.c

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/*-
* SPDX-License-Identifier: BSD-4-Clause
*
* Copyright (c) 1994 Herb Peyerl <hpeyerl@novatel.ca>
* Copyright (c) 2006 nCircle Network Security, Inc.
* All rights reserved.
*
* This software was developed by Robert N. M. Watson for the TrustedBSD
* Project under contract to nCircle Network Security, Inc.
*
* 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.
*
* $NetBSD: sysv_ipc.c,v 1.9 1995/06/02 19:04:22 mycroft Exp $
*/
2003-06-11 00:56:59 +00:00
#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/priv.h>
#include <sys/proc.h>
#include <sys/ucred.h>
#ifndef SYSVSHM
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;
}
#endif
/*
* 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. Unlike file system discretionary access
* control, the original create of an object is given the same rights as the
* current owner.
*/
int
ipcperm(struct thread *td, struct ipc_perm *perm, int acc_mode)
{
struct ucred *cred = td->td_ucred;
int error, obj_mode, dac_granted, priv_granted;
dac_granted = 0;
if (cred->cr_uid == perm->cuid || cred->cr_uid == perm->uid) {
obj_mode = perm->mode;
dac_granted |= IPC_M;
} else if (groupmember(perm->gid, cred) ||
groupmember(perm->cgid, cred)) {
obj_mode = perm->mode;
obj_mode <<= 3;
} else {
obj_mode = perm->mode;
obj_mode <<= 6;
}
/*
* While the System V IPC permission model allows IPC_M to be
* granted, as part of the mode, our implementation requires
* privilege to adminster the object if not the owner or creator.
*/
#if 0
if (obj_mode & IPC_M)
dac_granted |= IPC_M;
#endif
if (obj_mode & IPC_R)
dac_granted |= IPC_R;
if (obj_mode & IPC_W)
dac_granted |= IPC_W;
/*
* Simple case: all required rights are granted by DAC.
*/
if ((dac_granted & acc_mode) == acc_mode)
return (0);
/*
* Privilege is required to satisfy the request.
*/
priv_granted = 0;
if ((acc_mode & IPC_M) && !(dac_granted & IPC_M)) {
error = priv_check(td, PRIV_IPC_ADMIN);
if (error == 0)
priv_granted |= IPC_M;
}
if ((acc_mode & IPC_R) && !(dac_granted & IPC_R)) {
error = priv_check(td, PRIV_IPC_READ);
if (error == 0)
priv_granted |= IPC_R;
}
if ((acc_mode & IPC_W) && !(dac_granted & IPC_W)) {
error = priv_check(td, PRIV_IPC_WRITE);
if (error == 0)
priv_granted |= IPC_W;
}
if (((dac_granted | priv_granted) & acc_mode) == acc_mode)
return (0);
else
return (EACCES);
}
Change the ABI of some of the structures used by the SYSV IPC API: - The uid/cuid members of struct ipc_perm are now uid_t instead of unsigned short. - The gid/cgid members of struct ipc_perm are now gid_t instead of unsigned short. - The mode member of struct ipc_perm is now mode_t instead of unsigned short (this is merely a style bug). - The rather dubious padding fields for ABI compat with SV/I386 have been removed from struct msqid_ds and struct semid_ds. - The shm_segsz member of struct shmid_ds is now a size_t instead of an int. This removes the need for the shm_bsegsz member in struct shmid_kernel and should allow for complete support of SYSV SHM regions >= 2GB. - The shm_nattch member of struct shmid_ds is now an int instead of a short. - The shm_internal member of struct shmid_ds is now gone. The internal VM object pointer for SHM regions has been moved into struct shmid_kernel. - The existing __semctl(), msgctl(), and shmctl() system call entries are now marked COMPAT7 and new versions of those system calls which support the new ABI are now present. - The new system calls are assigned to the FBSD-1.1 version in libc. The FBSD-1.0 symbols in libc now refer to the old COMPAT7 system calls. - A simplistic framework for tagging system calls with compatibility symbol versions has been added to libc. Version tags are added to system calls by adding an appropriate __sym_compat() entry to src/lib/libc/incldue/compat.h. [1] PR: kern/16195 kern/113218 bin/129855 Reviewed by: arch@, rwatson Discussed with: kan, kib [1]
2009-06-24 21:10:52 +00:00
#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
void
ipcperm_old2new(struct ipc_perm_old *old, struct ipc_perm *new)
{
new->cuid = old->cuid;
new->cgid = old->cgid;
new->uid = old->uid;
new->gid = old->gid;
new->mode = old->mode;
new->seq = old->seq;
new->key = old->key;
}
void
ipcperm_new2old(struct ipc_perm *new, struct ipc_perm_old *old)
{
/* XXX: How to handle ID's > USHORT_MAX? */
old->cuid = new->cuid;
old->cgid = new->cgid;
old->uid = new->uid;
old->gid = new->gid;
old->mode = new->mode;
old->seq = new->seq;
old->key = new->key;
}
#endif
#ifdef COMPAT_FREEBSD32
#include <sys/mount.h>
#include <sys/socket.h>
#include <compat/freebsd32/freebsd32.h>
#include <compat/freebsd32/freebsd32_ipc.h>
#include <compat/freebsd32/freebsd32_proto.h>
#include <compat/freebsd32/freebsd32_signal.h>
#include <compat/freebsd32/freebsd32_syscall.h>
#include <compat/freebsd32/freebsd32_util.h>
#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
void
freebsd32_ipcperm_old_in(struct ipc_perm32_old *ip32, struct ipc_perm *ip)
{
CP(*ip32, *ip, cuid);
CP(*ip32, *ip, cgid);
CP(*ip32, *ip, uid);
CP(*ip32, *ip, gid);
CP(*ip32, *ip, mode);
CP(*ip32, *ip, seq);
CP(*ip32, *ip, key);
}
void
freebsd32_ipcperm_old_out(struct ipc_perm *ip, struct ipc_perm32_old *ip32)
{
CP(*ip, *ip32, cuid);
CP(*ip, *ip32, cgid);
CP(*ip, *ip32, uid);
CP(*ip, *ip32, gid);
CP(*ip, *ip32, mode);
CP(*ip, *ip32, seq);
CP(*ip, *ip32, key);
}
#endif
void
freebsd32_ipcperm_in(struct ipc_perm32 *ip32, struct ipc_perm *ip)
{
CP(*ip32, *ip, cuid);
CP(*ip32, *ip, cgid);
CP(*ip32, *ip, uid);
CP(*ip32, *ip, gid);
CP(*ip32, *ip, mode);
CP(*ip32, *ip, seq);
CP(*ip32, *ip, key);
}
void
freebsd32_ipcperm_out(struct ipc_perm *ip, struct ipc_perm32 *ip32)
{
CP(*ip, *ip32, cuid);
CP(*ip, *ip32, cgid);
CP(*ip, *ip32, uid);
CP(*ip, *ip32, gid);
CP(*ip, *ip32, mode);
CP(*ip, *ip32, seq);
CP(*ip, *ip32, key);
}
#endif