acd3428b7d
specific privilege names to a broad range of privileges. These may
require some future tweaking.
Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>
150 lines
4.4 KiB
C
150 lines
4.4 KiB
C
/* $NetBSD: sysv_ipc.c,v 1.7 1994/06/29 06:33:11 cgd Exp $ */
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/*-
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* Copyright (c) 1994 Herb Peyerl <hpeyerl@novatel.ca>
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* Copyright (c) 2006 nCircle Network Security, Inc.
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* All rights reserved.
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*
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* This software was developed by Robert N. M. Watson for the TrustedBSD
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* Project under contract to nCircle Network Security, 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. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by Herb Peyerl.
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* 4. The name of Herb Peyerl may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "opt_sysvipc.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/sem.h>
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#include <sys/shm.h>
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#include <sys/ipc.h>
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#include <sys/priv.h>
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#include <sys/proc.h>
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#include <sys/ucred.h>
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void (*shmfork_hook)(struct proc *, struct proc *) = NULL;
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void (*shmexit_hook)(struct vmspace *) = NULL;
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/* called from kern_fork.c */
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void
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shmfork(p1, p2)
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struct proc *p1, *p2;
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{
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if (shmfork_hook != NULL)
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shmfork_hook(p1, p2);
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return;
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}
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/* called from kern_exit.c */
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void
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shmexit(struct vmspace *vm)
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{
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if (shmexit_hook != NULL)
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shmexit_hook(vm);
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return;
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}
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/*
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* Check for IPC permission.
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*
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* Note: The MAC Framework does not require any modifications to the
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* ipcperm() function, as access control checks are performed throughout the
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* implementation of each primitive. Those entry point calls complement the
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* ipcperm() discertionary checks. Unlike file system discretionary access
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* control, the original create of an object is given the same rights as the
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* current owner.
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*/
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int
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ipcperm(struct thread *td, struct ipc_perm *perm, int acc_mode)
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{
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struct ucred *cred = td->td_ucred;
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int error, obj_mode, dac_granted, priv_granted;
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dac_granted = 0;
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if (cred->cr_uid == perm->cuid || cred->cr_uid == perm->uid) {
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obj_mode = perm->mode;
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dac_granted |= IPC_M;
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} else if (groupmember(perm->gid, cred) ||
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groupmember(perm->cgid, cred)) {
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obj_mode = perm->mode;
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obj_mode <<= 3;
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} else {
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obj_mode = perm->mode;
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obj_mode <<= 6;
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}
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/*
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* While the System V IPC permission model allows IPC_M to be
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* granted, as part of the mode, our implementation requires
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* privilege to adminster the object if not the owner or creator.
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*/
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#if 0
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if (obj_mode & IPC_M)
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dac_granted |= IPC_M;
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#endif
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if (obj_mode & IPC_R)
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dac_granted |= IPC_R;
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if (obj_mode & IPC_W)
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dac_granted |= IPC_W;
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/*
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* Simple case: all required rights are granted by DAC.
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*/
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if ((dac_granted & acc_mode) == acc_mode)
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return (0);
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/*
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* Privilege is required to satisfy the request.
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*/
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priv_granted = 0;
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if ((acc_mode & IPC_M) && !(dac_granted & IPC_M)) {
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error = priv_check(td, PRIV_IPC_ADMIN);
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if (error == 0)
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priv_granted |= IPC_M;
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}
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if ((acc_mode & IPC_R) && !(dac_granted & IPC_R)) {
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error = priv_check(td, PRIV_IPC_READ);
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if (error == 0)
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priv_granted |= IPC_R;
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}
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if ((acc_mode & IPC_W) && !(dac_granted & IPC_W)) {
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error = priv_check(td, PRIV_IPC_WRITE);
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if (error == 0)
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priv_granted |= IPC_W;
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}
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if (((dac_granted | priv_granted) & acc_mode) == acc_mode)
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return (0);
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else
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return (EACCES);
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}
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