security/mac_file.c

   1 /*-
   2  * Copyright (c) 2002, 2003 Networks Associates Technology, Inc.
   3  * Copyright (c) 2006 SPARTA, Inc.
   4  * All rights reserved.
   5  *
   6  * This software was developed for the FreeBSD Project in part by Network
   7  * Associates Laboratories, the Security Research Division of Network
   8  * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
   9  * as part of the DARPA CHATS research program.
  10  *
  11  * This software was enhanced by SPARTA ISSO under SPAWAR contract
  12  * N66001-04-C-6019 ("SEFOS").
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <sys/param.h>
  37 #include <sys/kernel.h>
  38 #include <sys/lock.h>
  39 #include <sys/malloc.h>
  40 #include <sys/proc.h>
  41 #include <sys/sbuf.h>
  42 #include <sys/systm.h>
  43 #include <sys/vnode.h>
  44 #include <sys/vnode_internal.h>
  45 #include <sys/file.h>
  46 #include <sys/file_internal.h>
  47
  48 #include <security/mac_internal.h>
  49
  50
  51 static struct label *
  52 mac_file_label_alloc(void)
  53 {
  54         struct label *label;
  55
  56         label = mac_labelzone_alloc(MAC_WAITOK);
  57         if (label == NULL) {
  58                 return NULL;
  59         }
  60         MAC_PERFORM(file_label_init, label);
  61         return label;
  62 }
  63
  64 void
  65 mac_file_label_init(struct fileglob *fg)
  66 {
  67         fg->fg_label = mac_file_label_alloc();
  68 }
  69
  70 static void
  71 mac_file_label_free(struct label *label)
  72 {
  73         MAC_PERFORM(file_label_destroy, label);
  74         mac_labelzone_free(label);
  75 }
  76
  77 void
  78 mac_file_label_associate(struct ucred *cred, struct fileglob *fg)
  79 {
  80         MAC_PERFORM(file_label_associate, cred, fg, fg->fg_label);
  81 }
  82
  83 void
  84 mac_file_label_destroy(struct fileglob *fg)
  85 {
  86         mac_file_label_free(fg->fg_label);
  87         fg->fg_label = NULL;
  88 }
  89
  90 int
  91 mac_file_check_create(struct ucred *cred)
  92 {
  93         int error;
  94
  95         MAC_CHECK(file_check_create, cred);
  96         return error;
  97 }
  98
  99 int
 100 mac_file_check_dup(struct ucred *cred, struct fileglob *fg, int newfd)
 101 {
 102         int error;
 103
 104         MAC_CHECK(file_check_dup, cred, fg, fg->fg_label, newfd);
 105         return error;
 106 }
 107
 108 int
 109 mac_file_check_fcntl(struct ucred *cred, struct fileglob *fg, int cmd,
 110     user_long_t arg)
 111 {
 112         int error;
 113
 114         MAC_CHECK(file_check_fcntl, cred, fg, fg->fg_label, cmd, arg);
 115         return error;
 116 }
 117
 118 int
 119 mac_file_check_ioctl(struct ucred *cred, struct fileglob *fg, u_int cmd)
 120 {
 121         int error;
 122
 123         MAC_CHECK(file_check_ioctl, cred, fg, fg->fg_label, cmd);
 124         return error;
 125 }
 126
 127 int
 128 mac_file_check_inherit(struct ucred *cred, struct fileglob *fg)
 129 {
 130         int error;
 131
 132         MAC_CHECK(file_check_inherit, cred, fg, fg->fg_label);
 133         return error;
 134 }
 135
 136 int
 137 mac_file_check_receive(struct ucred *cred, struct fileglob *fg)
 138 {
 139         int error;
 140
 141         MAC_CHECK(file_check_receive, cred, fg, fg->fg_label);
 142         return error;
 143 }
 144
 145 int
 146 mac_file_check_get_offset(struct ucred *cred, struct fileglob *fg)
 147 {
 148         int error;
 149
 150         MAC_CHECK(file_check_get_offset, cred, fg, fg->fg_label);
 151         return error;
 152 }
 153
 154 int
 155 mac_file_check_change_offset(struct ucred *cred, struct fileglob *fg)
 156 {
 157         int error;
 158
 159         MAC_CHECK(file_check_change_offset, cred, fg, fg->fg_label);
 160         return error;
 161 }
 162
 163 int
 164 mac_file_check_get(struct ucred *cred, struct fileglob *fg, char *elements,
 165     int len)
 166 {
 167         int error;
 168
 169         MAC_CHECK(file_check_get, cred, fg, elements, len);
 170         return error;
 171 }
 172
 173 int
 174 mac_file_check_set(struct ucred *cred, struct fileglob *fg, char *buf,
 175     int buflen)
 176 {
 177         int error;
 178
 179         MAC_CHECK(file_check_set, cred, fg, buf, buflen);
 180         return error;
 181 }
 182
 183 int
 184 mac_file_check_lock(struct ucred *cred, struct fileglob *fg, int op,
 185     struct flock *fl)
 186 {
 187         int error;
 188
 189         MAC_CHECK(file_check_lock, cred, fg, fg->fg_label, op, fl);
 190         return error;
 191 }
 192
 193 int
 194 mac_file_check_library_validation(struct proc *proc,
 195     struct fileglob *fg, off_t slice_offset,
 196     user_long_t error_message, size_t error_message_size)
 197 {
 198         int error;
 199
 200         MAC_CHECK(file_check_library_validation, proc, fg, slice_offset, error_message, error_message_size);
 201         return error;
 202 }
 203
 204 /*
 205  * On some platforms, VM_PROT_READ implies VM_PROT_EXECUTE. If that is true,
 206  * both prot and maxprot will have VM_PROT_EXECUTE set after file_check_mmap
 207  * if VM_PROT_READ is set.
 208  *
 209  * The type of maxprot in file_check_mmap must be equivalent to vm_prot_t *
 210  * (defined in <mach/vm_prot.h>). mac_policy.h does not include any header
 211  * files, so cannot use the typedef itself.
 212  */
 213 int
 214 mac_file_check_mmap(struct ucred *cred, struct fileglob *fg, int prot,
 215     int flags, uint64_t offset, int *maxprot)
 216 {
 217         int error;
 218         int maxp;
 219
 220         maxp = *maxprot;
 221         MAC_CHECK(file_check_mmap, cred, fg, fg->fg_label, prot, flags, offset, &maxp);
 222         if ((maxp | *maxprot) != *maxprot) {
 223                 panic("file_check_mmap increased max protections");
 224         }
 225         *maxprot = maxp;
 226         return error;
 227 }
 228
 229 void
 230 mac_file_check_mmap_downgrade(struct ucred *cred, struct fileglob *fg,
 231     int *prot)
 232 {
 233         int result = *prot;
 234
 235         MAC_PERFORM(file_check_mmap_downgrade, cred, fg, fg->fg_label,
 236             &result);
 237
 238         *prot = result;
 239 }
 240
 241
 242 /*
 243  * fileglob XATTR helpers.
 244  */
 245
 246 int
 247 mac_file_setxattr(struct fileglob *fg, const char *name, char *buf, size_t len)
 248 {
 249         struct vnode *vp = NULL;
 250
 251         if (!fg || FILEGLOB_DTYPE(fg) != DTYPE_VNODE) {
 252                 return EFTYPE;
 253         }
 254
 255         vp = (struct vnode *)fg->fg_data;
 256         return mac_vnop_setxattr(vp, name, buf, len);
 257 }
 258
 259 int
 260 mac_file_getxattr(struct fileglob *fg, const char *name, char *buf, size_t len,
 261     size_t *attrlen)
 262 {
 263         struct vnode *vp = NULL;
 264
 265         if (!fg || FILEGLOB_DTYPE(fg) != DTYPE_VNODE) {
 266                 return EFTYPE;
 267         }
 268
 269         vp = (struct vnode *)fg->fg_data;
 270         return mac_vnop_getxattr(vp, name, buf, len, attrlen);
 271 }
 272
 273 int
 274 mac_file_removexattr(struct fileglob *fg, const char *name)
 275 {
 276         struct vnode *vp = NULL;
 277
 278         if (!fg || FILEGLOB_DTYPE(fg) != DTYPE_VNODE) {
 279                 return EFTYPE;
 280         }
 281
 282         vp = (struct vnode *)fg->fg_data;
 283         return mac_vnop_removexattr(vp, name);
 284 }