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