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         MAC_PERFORM(file_label_init, label);
  60         return (label);
  61 }
  62
  63 void
  64 mac_file_label_init(struct fileglob *fg)
  65 {
  66
  67         fg->fg_label = mac_file_label_alloc();
  68 }
  69
  70 static void
  71 mac_file_label_free(struct label *label)
  72 {
  73
  74         MAC_PERFORM(file_label_destroy, label);
  75         mac_labelzone_free(label);
  76 }
  77
  78 void
  79 mac_file_label_associate(struct ucred *cred, struct fileglob *fg)
  80 {
  81
  82         MAC_PERFORM(file_label_associate, cred, fg, fg->fg_label);
  83 }
  84
  85 void
  86 mac_file_label_destroy(struct fileglob *fg)
  87 {
  88
  89         mac_file_label_free(fg->fg_label);
  90         fg->fg_label = NULL;
  91 }
  92
  93 int
  94 mac_file_check_create(struct ucred *cred)
  95 {
  96         int error;
  97
  98         MAC_CHECK(file_check_create, cred);
  99         return (error);
 100 }
 101
 102 int
 103 mac_file_check_dup(struct ucred *cred, struct fileglob *fg, int newfd)
 104 {
 105         int error;
 106
 107         MAC_CHECK(file_check_dup, cred, fg, fg->fg_label, newfd);
 108         return (error);
 109 }
 110
 111 int
 112 mac_file_check_fcntl(struct ucred *cred, struct fileglob *fg, int cmd,
 113     user_long_t arg)
 114 {
 115         int error;
 116
 117         MAC_CHECK(file_check_fcntl, cred, fg, fg->fg_label, cmd, arg);
 118         return (error);
 119 }
 120
 121 int
 122 mac_file_check_ioctl(struct ucred *cred, struct fileglob *fg, u_int cmd)
 123 {
 124         int error;
 125
 126         MAC_CHECK(file_check_ioctl, cred, fg, fg->fg_label, cmd);
 127         return (error);
 128 }
 129
 130 int
 131 mac_file_check_inherit(struct ucred *cred, struct fileglob *fg)
 132 {
 133         int error;
 134
 135         MAC_CHECK(file_check_inherit, cred, fg, fg->fg_label);
 136         return (error);
 137 }
 138
 139 int
 140 mac_file_check_receive(struct ucred *cred, struct fileglob *fg)
 141 {
 142         int error;
 143
 144         MAC_CHECK(file_check_receive, cred, fg, fg->fg_label);
 145         return (error);
 146 }
 147
 148 int
 149 mac_file_check_get_offset(struct ucred *cred, struct fileglob *fg)
 150 {
 151         int error;
 152
 153         MAC_CHECK(file_check_get_offset, cred, fg, fg->fg_label);
 154         return (error);
 155 }
 156
 157 int
 158 mac_file_check_change_offset(struct ucred *cred, struct fileglob *fg)
 159 {
 160         int error;
 161
 162         MAC_CHECK(file_check_change_offset, cred, fg, fg->fg_label);
 163         return (error);
 164 }
 165
 166 int
 167 mac_file_check_get(struct ucred *cred, struct fileglob *fg, char *elements,
 168     int len)
 169 {
 170         int error;
 171
 172         MAC_CHECK(file_check_get, cred, fg, elements, len);
 173         return (error);
 174 }
 175
 176 int
 177 mac_file_check_set(struct ucred *cred, struct fileglob *fg, char *buf,
 178     int buflen)
 179 {
 180         int error;
 181
 182         MAC_CHECK(file_check_set, cred, fg, buf, buflen);
 183         return (error);
 184 }
 185
 186 int
 187 mac_file_check_lock(struct ucred *cred, struct fileglob *fg, int op,
 188     struct flock *fl)
 189 {
 190         int error;
 191
 192         MAC_CHECK(file_check_lock, cred, fg, fg->fg_label, op, fl);
 193         return (error);
 194 }
 195
 196 int
 197 mac_file_check_library_validation(struct proc *proc,
 198         struct fileglob *fg, off_t slice_offset,
 199         user_long_t error_message, size_t error_message_size)
 200 {
 201         int error;
 202
 203         MAC_CHECK(file_check_library_validation, proc, fg, slice_offset, error_message, error_message_size);
 204         return (error);
 205 }
 206
 207 /*
 208  * On some platforms, VM_PROT_READ implies VM_PROT_EXECUTE. If that is true,
 209  * both prot and maxprot will have VM_PROT_EXECUTE set after file_check_mmap
 210  * if VM_PROT_READ is set.
 211  *
 212  * The type of maxprot in file_check_mmap must be equivalent to vm_prot_t *
 213  * (defined in <mach/vm_prot.h>). mac_policy.h does not include any header
 214  * files, so cannot use the typedef itself.
 215  */
 216 int
 217 mac_file_check_mmap(struct ucred *cred, struct fileglob *fg, int prot,
 218     int flags, uint64_t offset, int *maxprot)
 219 {
 220         int error;
 221         int maxp;
 222
 223         maxp = *maxprot;
 224         MAC_CHECK(file_check_mmap, cred, fg, fg->fg_label, prot, flags, offset, &maxp);
 225         if ((maxp | *maxprot) != *maxprot)
 226                 panic("file_check_mmap increased max protections");
 227         *maxprot = maxp;
 228         return (error);
 229 }
 230
 231 void
 232 mac_file_check_mmap_downgrade(struct ucred *cred, struct fileglob *fg,
 233     int *prot)
 234 {
 235         int result = *prot;
 236
 237         MAC_PERFORM(file_check_mmap_downgrade, cred, fg, fg->fg_label,
 238             &result);
 239
 240         *prot = result;
 241 }
 242
 243
 244 /*
 245  * fileglob XATTR helpers.
 246  */
 247
 248 int
 249 mac_file_setxattr(struct fileglob *fg, const char *name, char *buf, size_t len) {
 250         struct vnode *vp = NULL;
 251
 252         if (!fg || FILEGLOB_DTYPE(fg) != DTYPE_VNODE) {
 253                 return EFTYPE;
 254         }
 255
 256         vp = (struct vnode *)fg->fg_data;
 257         return mac_vnop_setxattr(vp, name, buf, len);
 258 }
 259
 260 int
 261 mac_file_getxattr(struct fileglob *fg, const char *name, char *buf, size_t len,
 262                 size_t *attrlen) {
 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         struct vnode *vp = NULL;
 276
 277         if (!fg || FILEGLOB_DTYPE(fg) != DTYPE_VNODE) {
 278                 return EFTYPE;
 279         }
 280
 281         vp = (struct vnode *)fg->fg_data;
 282         return mac_vnop_removexattr(vp, name);
 283 }