1 /* 2 * (The copyright below applies to ufs_access()) 3 * 4 * Copyright (c) 1982, 1986, 1989, 1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)ufs_vnops.c 8.27 (Berkeley) 5/27/95 41 * $DragonFly: src/sys/kern/vfs_helper.c,v 1.1 2007/11/02 19:54:14 dillon Exp $ 42 */ 43 44 #include "opt_quota.h" 45 #include "opt_suiddir.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/fcntl.h> 51 #include <sys/stat.h> 52 #include <sys/mount.h> 53 #include <sys/unistd.h> 54 #include <sys/vnode.h> 55 #include <sys/file.h> /* XXX */ 56 57 /* 58 * vop_helper_access() 59 * 60 * Provide standard UNIX semanics for VOP_ACCESS, but without the quota 61 * code. This procedure was basically pulled out of UFS. 62 */ 63 int 64 vop_helper_access(struct vop_access_args *ap, uid_t ino_uid, gid_t ino_gid, 65 mode_t ino_mode, u_int32_t ino_flags) 66 { 67 struct vnode *vp = ap->a_vp; 68 struct ucred *cred = ap->a_cred; 69 mode_t mask, mode = ap->a_mode; 70 gid_t *gp; 71 int i; 72 #ifdef QUOTA 73 /*int error;*/ 74 #endif 75 76 /* 77 * Disallow write attempts on read-only filesystems; 78 * unless the file is a socket, fifo, or a block or 79 * character device resident on the filesystem. 80 */ 81 if (mode & VWRITE) { 82 switch (vp->v_type) { 83 case VDIR: 84 case VLNK: 85 case VREG: 86 case VDATABASE: 87 if (vp->v_mount->mnt_flag & MNT_RDONLY) 88 return (EROFS); 89 #ifdef QUOTA 90 /* check quota here XXX */ 91 #endif 92 break; 93 default: 94 break; 95 } 96 } 97 98 /* If immutable bit set, nobody gets to write it. */ 99 if ((mode & VWRITE) && (ino_flags & IMMUTABLE)) 100 return (EPERM); 101 102 /* Otherwise, user id 0 always gets access. */ 103 if (cred->cr_uid == 0) 104 return (0); 105 106 mask = 0; 107 108 /* Otherwise, check the owner. */ 109 if (cred->cr_uid == ino_uid) { 110 if (mode & VEXEC) 111 mask |= S_IXUSR; 112 if (mode & VREAD) 113 mask |= S_IRUSR; 114 if (mode & VWRITE) 115 mask |= S_IWUSR; 116 return ((ino_mode & mask) == mask ? 0 : EACCES); 117 } 118 119 /* Otherwise, check the groups. */ 120 for (i = 0, gp = cred->cr_groups; i < cred->cr_ngroups; i++, gp++) 121 if (ino_gid == *gp) { 122 if (mode & VEXEC) 123 mask |= S_IXGRP; 124 if (mode & VREAD) 125 mask |= S_IRGRP; 126 if (mode & VWRITE) 127 mask |= S_IWGRP; 128 return ((ino_mode & mask) == mask ? 0 : EACCES); 129 } 130 131 /* Otherwise, check everyone else. */ 132 if (mode & VEXEC) 133 mask |= S_IXOTH; 134 if (mode & VREAD) 135 mask |= S_IROTH; 136 if (mode & VWRITE) 137 mask |= S_IWOTH; 138 return ((ino_mode & mask) == mask ? 0 : EACCES); 139 } 140 141