sys/chmodx_np.c

   1 /*
   2  * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 #include <sys/types.h>
  24 #include <sys/acl.h>
  25 #include <errno.h>
  26 #include <fcntl.h>
  27 #include <unistd.h>
  28 #include <uuid/uuid.h>
  29
  30 #if 1 /* for turdfile code only */
  31 #include <string.h>
  32 #include <sys/stat.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #endif
  36
  37 static int chmodx_syscall(void *obj, uid_t fsowner, gid_t fsgrp, int mode, struct kauth_filesec *fsacl);
  38 static int fchmodx_syscall(void *obj, uid_t fsowner, gid_t fsgrp, int mode, struct kauth_filesec *fsacl);
  39
  40 static int chmodx1(void *obj,
  41                    int (* chmod_syscall)(void *obj, uid_t fsowner, gid_t fsgrp, int mode,
  42                                        struct kauth_filesec *fsacl),
  43                    filesec_t fsec);
  44
  45 /*
  46  * Chmod interfaces.
  47  */
  48 int
  49 chmodx_np(const char *path, filesec_t fsec)
  50 {
  51         return(chmodx1((void *)&path, chmodx_syscall, fsec));
  52 }
  53
  54 int
  55 fchmodx_np(int fd, filesec_t fsec)
  56 {
  57         return(chmodx1((void *)&fd, fchmodx_syscall, fsec));
  58 }
  59
  60 /*
  61  * Chmod syscalls.
  62  */
  63 extern int __chmod_extended(char *, uid_t, gid_t, int, struct kauth_filesec *);
  64 extern int __fchmod_extended(int, uid_t, gid_t, int, struct kauth_filesec *);
  65
  66 static int
  67 chmodx_syscall(void *obj, uid_t fsowner, gid_t fsgrp, int mode, struct kauth_filesec *fsacl)
  68 {
  69         char *path = *(char **)obj;
  70
  71         return(__chmod_extended(path, fsowner, fsgrp, mode, fsacl));
  72 }
  73
  74 static int
  75 fchmodx_syscall(void *obj, uid_t fsowner, gid_t fsgrp, int mode, struct kauth_filesec *fsacl)
  76 {
  77         int fd = *(int *)obj;
  78         return(__fchmod_extended(fd, fsowner, fsgrp, mode, fsacl));
  79 }
  80
  81 /*
  82  * Chmod internals.
  83  */
  84
  85 static int
  86 chmodx1(void *obj,
  87     int (chmod_syscall)(void *obj, uid_t fsowner, gid_t fsgrp, int mode, struct kauth_filesec *fsacl),
  88     filesec_t fsec)
  89 {
  90         uid_t fsowner = KAUTH_UID_NONE;
  91         gid_t fsgrp = KAUTH_GID_NONE;
  92         mode_t fsec_mode;
  93         int fsmode = -1;
  94         size_t size = 0;
  95         int fsacl_used = 0;
  96         int delete_acl = 0;
  97         struct kauth_filesec *fsacl = NULL;
  98         struct kauth_filesec static_filesec;
  99
 100         if (fsec == NULL) {
 101                 errno = EINVAL;
 102                 return(-1);
 103         }
 104
 105         /* regular properties */
 106         if ((filesec_get_property(fsec, FILESEC_OWNER, &fsowner) != 0) && (errno != ENOENT))
 107                 return(-1);
 108         if ((filesec_get_property(fsec, FILESEC_GROUP, &fsgrp) != 0) && (errno != ENOENT))
 109                 return(-1);
 110         if ((filesec_get_property(fsec, FILESEC_MODE, &fsec_mode)) != 0) {
 111                 if (errno != ENOENT)
 112                         return(-1);
 113         } else {
 114                 /* cast up */
 115                 fsmode = fsec_mode;
 116         }
 117
 118         /*
 119          * We can set any or all of the ACL and UUIDs, but the two are transported in one
 120          * structure.  If we have an ACL, we'll use its allocated structure, otherwise we
 121          * need our own.
 122          */
 123         if (((filesec_get_property(fsec, FILESEC_ACL_RAW, &fsacl) != 0) ||
 124                 (filesec_get_property(fsec, FILESEC_ACL_ALLOCSIZE, &size) != 0)) &&
 125             (errno != ENOENT))
 126                 return(-1);
 127         /* caller wants to delete ACL, must remember this */
 128         if (fsacl == _FILESEC_REMOVE_ACL) {
 129                 delete_acl = 1;
 130                 fsacl = 0;
 131         }
 132
 133         /* no ACL, use local filesec */
 134         if (fsacl == NULL) {
 135                 bzero(&static_filesec, sizeof(static_filesec));
 136                 fsacl = &static_filesec;
 137                 fsacl->fsec_magic = KAUTH_FILESEC_MAGIC;
 138                 fsacl->fsec_entrycount = KAUTH_FILESEC_NOACL;
 139         } else {
 140                 fsacl_used = 1;
 141         }
 142
 143         /* grab the owner and group UUID if present */
 144         if (filesec_get_property(fsec, FILESEC_UUID, &fsacl->fsec_owner) != 0) {
 145                 if (errno != ENOENT)
 146                         return(-1);
 147                 bzero(&fsacl->fsec_owner, sizeof(fsacl->fsec_owner));
 148         } else {
 149                 fsacl_used = 1;
 150         }
 151         if (filesec_get_property(fsec, FILESEC_GRPUUID, &fsacl->fsec_group) != 0) {
 152                 if (errno != ENOENT)
 153                         return(-1);
 154                 bzero(&fsacl->fsec_group, sizeof(fsacl->fsec_group));
 155         } else {
 156                 fsacl_used = 1;
 157         }
 158
 159         /* after all this, if we didn't find anything that needs it, don't pass it in */
 160         if (!fsacl_used) {
 161                 /*
 162                  * If the caller was trying to remove the ACL, and there are no UUIDs,
 163                  * we can tell the kernel to completely nuke the whole datastructure.
 164                  */
 165                 if (delete_acl) {
 166                         fsacl = _FILESEC_REMOVE_ACL;
 167                 } else {
 168                         fsacl = NULL;
 169                 }
 170         }
 171
 172         return(chmod_syscall(obj, fsowner, fsgrp, fsmode, fsacl));
 173 }