1 /* $NetBSD: sysv_ipc.c,v 1.7 1994/06/29 06:33:11 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1994 Herb Peyerl <hpeyerl@novatel.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Herb Peyerl. 18 * 4. The name of Herb Peyerl may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <sys/param.h> 34 #include <sys/kernel.h> 35 #include <sys/proc.h> 36 #include <sys/ipc.h> 37 #include <sys/systm.h> 38 39 /* 40 * Check for ipc permission 41 */ 42 43 int 44 ipcperm(cred, perm, mode) 45 struct ucred *cred; 46 struct ipc_perm *perm; 47 int mode; 48 { 49 50 if (cred->cr_uid == 0) 51 return (0); 52 53 /* Check for user match. */ 54 if (cred->cr_uid != perm->cuid && cred->cr_uid != perm->uid) { 55 if (mode & IPC_M) 56 return (EPERM); 57 /* Check for group match. */ 58 mode >>= 3; 59 if (!groupmember(perm->gid, cred) && 60 !groupmember(perm->cgid, cred)) 61 /* Check for `other' match. */ 62 mode >>= 3; 63 } 64 65 if (mode & IPC_M) 66 return (0); 67 return ((mode & perm->mode) == mode ? 0 : EACCES); 68 } 69