module/zfs/zfs_byteswap.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or https://opensource.org/licenses/CDDL-1.0.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #include <sys/zfs_context.h>
  27 #include <sys/vfs.h>
  28 #include <sys/fs/zfs.h>
  29 #include <sys/zfs_znode.h>
  30 #include <sys/zfs_sa.h>
  31 #include <sys/zfs_acl.h>
  32
  33 #ifndef _KERNEL
  34 static
  35 #endif
  36 void
  37 zfs_oldace_byteswap(ace_t *ace, int ace_cnt)
  38 {
  39         for (int i = 0; i != ace_cnt; i++, ace++) {
  40                 ace->a_who = BSWAP_32(ace->a_who);
  41                 ace->a_access_mask = BSWAP_32(ace->a_access_mask);
  42                 ace->a_flags = BSWAP_16(ace->a_flags);
  43                 ace->a_type = BSWAP_16(ace->a_type);
  44         }
  45 }
  46
  47 /*
  48  * swap ace_t and ace_object_t
  49  */
  50 #ifndef _KERNEL
  51 static
  52 #endif
  53 void
  54 zfs_ace_byteswap(void *buf, size_t size, boolean_t zfs_layout)
  55 {
  56         caddr_t end;
  57         caddr_t ptr;
  58         zfs_ace_t *zacep = NULL;
  59         ace_t *acep;
  60         uint16_t entry_type;
  61         size_t entry_size;
  62         int ace_type;
  63
  64         end = (caddr_t)buf + size;
  65         ptr = buf;
  66
  67         while (ptr < end) {
  68                 if (zfs_layout) {
  69                         /*
  70                          * Avoid overrun.  Embedded aces can have one
  71                          * of several sizes.  We don't know exactly
  72                          * how many our present, only the size of the
  73                          * buffer containing them.  That size may be
  74                          * larger than needed to hold the aces
  75                          * present.  As long as we do not do any
  76                          * swapping beyond the end of our block we are
  77                          * okay.  It is safe to swap any non-ace data
  78                          * within the block since it is just zeros.
  79                          */
  80                         if (ptr + sizeof (zfs_ace_hdr_t) > end) {
  81                                 break;
  82                         }
  83                         zacep = (zfs_ace_t *)ptr;
  84                         zacep->z_hdr.z_access_mask =
  85                             BSWAP_32(zacep->z_hdr.z_access_mask);
  86                         zacep->z_hdr.z_flags = BSWAP_16(zacep->z_hdr.z_flags);
  87                         ace_type = zacep->z_hdr.z_type =
  88                             BSWAP_16(zacep->z_hdr.z_type);
  89                         entry_type = zacep->z_hdr.z_flags & ACE_TYPE_FLAGS;
  90                 } else {
  91                         /* Overrun avoidance */
  92                         if (ptr + sizeof (ace_t) > end) {
  93                                 break;
  94                         }
  95                         acep = (ace_t *)ptr;
  96                         acep->a_access_mask = BSWAP_32(acep->a_access_mask);
  97                         acep->a_flags = BSWAP_16(acep->a_flags);
  98                         ace_type = acep->a_type = BSWAP_16(acep->a_type);
  99                         acep->a_who = BSWAP_32(acep->a_who);
 100                         entry_type = acep->a_flags & ACE_TYPE_FLAGS;
 101                 }
 102                 switch (entry_type) {
 103                 case ACE_OWNER:
 104                 case ACE_EVERYONE:
 105                 case (ACE_IDENTIFIER_GROUP | ACE_GROUP):
 106                         entry_size = zfs_layout ?
 107                             sizeof (zfs_ace_hdr_t) : sizeof (ace_t);
 108                         break;
 109                 case ACE_IDENTIFIER_GROUP:
 110                 default:
 111                         /* Overrun avoidance */
 112                         if (zfs_layout) {
 113                                 if (ptr + sizeof (zfs_ace_t) <= end) {
 114                                         zacep->z_fuid = BSWAP_64(zacep->z_fuid);
 115                                 } else {
 116                                         entry_size = sizeof (zfs_ace_t);
 117                                         break;
 118                                 }
 119                         }
 120                         switch (ace_type) {
 121                         case ACE_ACCESS_ALLOWED_OBJECT_ACE_TYPE:
 122                         case ACE_ACCESS_DENIED_OBJECT_ACE_TYPE:
 123                         case ACE_SYSTEM_AUDIT_OBJECT_ACE_TYPE:
 124                         case ACE_SYSTEM_ALARM_OBJECT_ACE_TYPE:
 125                                 entry_size = zfs_layout ?
 126                                     sizeof (zfs_object_ace_t) :
 127                                     sizeof (ace_object_t);
 128                                 break;
 129                         default:
 130                                 entry_size = zfs_layout ? sizeof (zfs_ace_t) :
 131                                     sizeof (ace_t);
 132                                 break;
 133                         }
 134                 }
 135                 ptr = ptr + entry_size;
 136         }
 137 }
 138
 139 void
 140 zfs_oldacl_byteswap(void *buf, size_t size)
 141 {
 142         /*
 143          * Arggh, since we don't know how many ACEs are in
 144          * the array, we have to swap the entire block
 145          */
 146         zfs_oldace_byteswap((ace_t *)buf, size / sizeof (ace_t));
 147 }
 148
 149 void
 150 zfs_acl_byteswap(void *buf, size_t size)
 151 {
 152         zfs_ace_byteswap(buf, size, B_TRUE);
 153 }
 154
 155 void
 156 zfs_znode_byteswap(void *buf, size_t size)
 157 {
 158         znode_phys_t *zp = buf;
 159
 160         ASSERT(size >= sizeof (znode_phys_t));
 161
 162         zp->zp_crtime[0] = BSWAP_64(zp->zp_crtime[0]);
 163         zp->zp_crtime[1] = BSWAP_64(zp->zp_crtime[1]);
 164         zp->zp_atime[0] = BSWAP_64(zp->zp_atime[0]);
 165         zp->zp_atime[1] = BSWAP_64(zp->zp_atime[1]);
 166         zp->zp_mtime[0] = BSWAP_64(zp->zp_mtime[0]);
 167         zp->zp_mtime[1] = BSWAP_64(zp->zp_mtime[1]);
 168         zp->zp_ctime[0] = BSWAP_64(zp->zp_ctime[0]);
 169         zp->zp_ctime[1] = BSWAP_64(zp->zp_ctime[1]);
 170         zp->zp_gen = BSWAP_64(zp->zp_gen);
 171         zp->zp_mode = BSWAP_64(zp->zp_mode);
 172         zp->zp_size = BSWAP_64(zp->zp_size);
 173         zp->zp_parent = BSWAP_64(zp->zp_parent);
 174         zp->zp_links = BSWAP_64(zp->zp_links);
 175         zp->zp_xattr = BSWAP_64(zp->zp_xattr);
 176         zp->zp_rdev = BSWAP_64(zp->zp_rdev);
 177         zp->zp_flags = BSWAP_64(zp->zp_flags);
 178         zp->zp_uid = BSWAP_64(zp->zp_uid);
 179         zp->zp_gid = BSWAP_64(zp->zp_gid);
 180         zp->zp_zap = BSWAP_64(zp->zp_zap);
 181         zp->zp_pad[0] = BSWAP_64(zp->zp_pad[0]);
 182         zp->zp_pad[1] = BSWAP_64(zp->zp_pad[1]);
 183         zp->zp_pad[2] = BSWAP_64(zp->zp_pad[2]);
 184
 185         zp->zp_acl.z_acl_extern_obj = BSWAP_64(zp->zp_acl.z_acl_extern_obj);
 186         zp->zp_acl.z_acl_size = BSWAP_32(zp->zp_acl.z_acl_size);
 187         zp->zp_acl.z_acl_version = BSWAP_16(zp->zp_acl.z_acl_version);
 188         zp->zp_acl.z_acl_count = BSWAP_16(zp->zp_acl.z_acl_count);
 189         if (zp->zp_acl.z_acl_version == ZFS_ACL_VERSION) {
 190                 zfs_acl_byteswap((void *)&zp->zp_acl.z_ace_data[0],
 191                     ZFS_ACE_SPACE);
 192         } else {
 193                 zfs_oldace_byteswap((ace_t *)&zp->zp_acl.z_ace_data[0],
 194                     ACE_SLOT_CNT);
 195         }
 196 }
 197
 198 #if defined(_KERNEL)
 199 EXPORT_SYMBOL(zfs_oldacl_byteswap);
 200 EXPORT_SYMBOL(zfs_acl_byteswap);
 201 EXPORT_SYMBOL(zfs_znode_byteswap);
 202 #endif