1 /* $NetBSD: sysv_ipc.c,v 1.17 2006/05/14 21:15:11 elad Exp $ */ 2 3 /*- 4 * Copyright (c) 1998 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Charles M. Hannum. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: sysv_ipc.c,v 1.17 2006/05/14 21:15:11 elad Exp $"); 41 42 #include <sys/param.h> 43 #include <sys/kernel.h> 44 #include <sys/proc.h> 45 #include <sys/ipc.h> 46 #include <sys/systm.h> 47 #include <sys/mount.h> 48 #include <sys/vnode.h> 49 #include <sys/stat.h> 50 #include <sys/kauth.h> 51 52 /* 53 * Check for ipc permission 54 */ 55 56 int 57 ipcperm(kauth_cred_t cred, struct ipc_perm *perm, int mode) 58 { 59 mode_t mask; 60 int ismember = 0; 61 62 if (kauth_cred_geteuid(cred) == 0) 63 return (0); 64 65 if (mode == IPC_M) { 66 if (kauth_cred_geteuid(cred) == perm->uid || 67 kauth_cred_geteuid(cred) == perm->cuid) 68 return (0); 69 return (EPERM); 70 } 71 72 mask = 0; 73 74 if (kauth_cred_geteuid(cred) == perm->uid || 75 kauth_cred_geteuid(cred) == perm->cuid) { 76 if (mode & IPC_R) 77 mask |= S_IRUSR; 78 if (mode & IPC_W) 79 mask |= S_IWUSR; 80 return ((perm->mode & mask) == mask ? 0 : EACCES); 81 } 82 83 if (kauth_cred_getegid(cred) == perm->gid || 84 (kauth_cred_ismember_gid(cred, perm->gid, &ismember) == 0 && ismember) || 85 kauth_cred_getegid(cred) == perm->cgid || 86 (kauth_cred_ismember_gid(cred, perm->cgid, &ismember) == 0 && ismember)) { 87 if (mode & IPC_R) 88 mask |= S_IRGRP; 89 if (mode & IPC_W) 90 mask |= S_IWGRP; 91 return ((perm->mode & mask) == mask ? 0 : EACCES); 92 } 93 94 if (mode & IPC_R) 95 mask |= S_IROTH; 96 if (mode & IPC_W) 97 mask |= S_IWOTH; 98 return ((perm->mode & mask) == mask ? 0 : EACCES); 99 } 100