bsd/kern/sysv_ipc.c

   1 /*
   2  * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License.  The rights granted to you under the
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*      $NetBSD: sysv_ipc.c,v 1.7 1994/06/29 06:33:11 cgd Exp $ */
  31
  32 /*
  33  * Copyright (c) 1994 Herb Peyerl <hpeyerl@novatel.ca>
  34  * All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  * 1. Redistributions of source code must retain the above copyright
  40  *    notice, this list of conditions and the following disclaimer.
  41  * 2. Redistributions in binary form must reproduce the above copyright
  42  *    notice, this list of conditions and the following disclaimer in the
  43  *    documentation and/or other materials provided with the distribution.
  44  * 3. All advertising materials mentioning features or use of this software
  45  *    must display the following acknowledgement:
  46  *      This product includes software developed by Herb Peyerl.
  47  * 4. The name of Herb Peyerl may not be used to endorse or promote products
  48  *    derived from this software without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  51  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  52  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  53  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  54  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  55  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  56  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  57  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  58  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  59  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  60  */
  61
  62
  63 #include <sys/param.h>
  64 #include <sys/ipc.h>
  65 #include <sys/ucred.h>
  66 #include <sys/kauth.h>
  67
  68
  69 /*
  70  * Check for ipc permission
  71  *
  72  * XXX: Should pass proc argument so that we can pass
  73  * XXX: proc->p_acflag to suser()
  74  */
  75
  76 int
  77 ipcperm(kauth_cred_t cred, struct ipc_perm *perm, int mode)
  78 {
  79
  80         if (!suser(cred, (u_short *)NULL))
  81                 return (0);
  82
  83         /* Check for user match. */
  84         if (kauth_cred_getuid(cred) != perm->cuid && kauth_cred_getuid(cred) != perm->uid) {
  85                 int is_member;
  86
  87                 if (mode & IPC_M)
  88                         return (EPERM);
  89                 /* Check for group match. */
  90                 mode >>= 3;
  91                 if ((kauth_cred_ismember_gid(cred, perm->gid, &is_member) || !is_member) &&
  92                     (kauth_cred_ismember_gid(cred, perm->cgid, &is_member) || !is_member))
  93                         /* Check for `other' match. */
  94                         mode >>= 3;
  95         }
  96
  97         if (mode & IPC_M)
  98                 return (0);
  99         return ((mode & perm->mode) == mode ? 0 : EACCES);
 100 }