sys/ufs/ffs/ffs_appleufs.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (c) 2002 Darrin B. Jewell
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by Darrin B. Jewell
  18  * 4. The name of the author may not be used to endorse or promote products
  19  *    derived from this software without specific prior written permission
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 #include <sys/cdefs.h>
  34 __KERNEL_RCSID(0, "$NetBSD$");
  35
  36 #include <sys/param.h>
  37 #include <sys/time.h>
  38 #if defined(_KERNEL)
  39 #include <sys/kernel.h>
  40 #include <sys/systm.h>
  41 #endif
  42
  43 #include <ufs/ufs/dinode.h>
  44 #include <ufs/ufs/ufs_bswap.h>
  45 #include <ufs/ffs/fs.h>
  46 #include <ufs/ffs/ffs_extern.h>
  47
  48 #if !defined(_KERNEL) && !defined(STANDALONE)
  49 #include <stddef.h>
  50 #include <stdio.h>
  51 #include <stdlib.h>
  52 #include <string.h>
  53 #include <errno.h>
  54 #include <assert.h>
  55 #define KASSERT(x) assert(x)
  56 #endif
  57
  58 /*
  59  * this is the same calculation as in_cksum
  60  */
  61 u_int16_t
  62 ffs_appleufs_cksum(const struct appleufslabel *appleufs)
  63 {
  64         const u_int16_t *p = (const u_int16_t *)appleufs;
  65         int len = APPLEUFS_LABEL_SIZE; /* sizeof(struct appleufslabel) */
  66         long res = 0;
  67         while (len > 1)  {
  68                 res += *p++;
  69                 len -= 2;
  70         }
  71 #if 0 /* APPLEUFS_LABEL_SIZE is guaranteed to be even */
  72         if (len == 1)
  73                 res += htobe16(*(u_char *)p<<8);
  74 #endif
  75         res = (res >> 16) + (res & 0xffff);
  76         res += (res >> 16);
  77         return (~res);
  78 }
  79
  80 /* copies o to n, validating and byteswapping along the way
  81  * returns 0 if ok, EINVAL if not valid
  82  */
  83 int
  84 ffs_appleufs_validate(const char *name, const struct appleufslabel *o,
  85     struct appleufslabel *n)
  86 {
  87         struct appleufslabel tmp;
  88         if (!n) n = &tmp;
  89
  90         if (o->ul_magic != be32toh(APPLEUFS_LABEL_MAGIC)) {
  91                 return EINVAL;
  92         }
  93         *n = *o;
  94         n->ul_checksum = 0;
  95         n->ul_checksum = ffs_appleufs_cksum(n);
  96         if (n->ul_checksum != o->ul_checksum) {
  97 #if defined(DIAGNOSTIC) || !defined(_KERNEL)
  98                 printf("%s: invalid APPLE UFS checksum. found 0x%x, expecting 0x%x",
  99                         name,o->ul_checksum,n->ul_checksum);
 100 #endif
 101                 return EINVAL;
 102         }
 103         n->ul_magic = be32toh(o->ul_magic);
 104         n->ul_version = be32toh(o->ul_version);
 105         n->ul_time = be32toh(o->ul_time);
 106         n->ul_namelen = be16toh(o->ul_namelen);
 107
 108         if (n->ul_namelen > APPLEUFS_MAX_LABEL_NAME) {
 109 #if defined(DIAGNOSTIC) || !defined(_KERNEL)
 110                 printf("%s: APPLE UFS label name too long, truncated.\n",
 111                                 name);
 112 #endif
 113                 n->ul_namelen = APPLEUFS_MAX_LABEL_NAME;
 114         }
 115         /* if len is max, will set ul_unused1 */
 116         n->ul_name[n->ul_namelen] = '\0';
 117
 118 #ifdef DEBUG
 119         printf("%s: found APPLE UFS label v%d: \"%s\"\n",
 120             name,n->ul_version,n->ul_name);
 121 #endif
 122         n->ul_uuid = be64toh(o->ul_uuid);
 123
 124         return 0;
 125 }
 126
 127 void
 128 ffs_appleufs_set(struct appleufslabel *appleufs, const char *name, time_t t,
 129     uint64_t uuid)
 130 {
 131         size_t namelen;
 132         if (!name) name = "untitled";
 133         if (t == ((time_t)-1)) {
 134 #if defined(_KERNEL)
 135                 t = time_second;
 136 #elif defined(STANDALONE)
 137                 t = 0;
 138 #else
 139                 (void)time(&t);
 140 #endif
 141         }
 142         if (uuid == 0) {
 143 #if defined(_KERNEL) && !defined(STANDALONE)
 144                 uuid = arc4random();
 145                 uuid <<= 32;
 146                 uuid |= arc4random();
 147 #endif
 148         }
 149         namelen = strlen(name);
 150         if (namelen > APPLEUFS_MAX_LABEL_NAME)
 151                 namelen = APPLEUFS_MAX_LABEL_NAME;
 152         memset(appleufs, 0, APPLEUFS_LABEL_SIZE);
 153         appleufs->ul_magic   = htobe32(APPLEUFS_LABEL_MAGIC);
 154         appleufs->ul_version = htobe32(APPLEUFS_LABEL_VERSION);
 155         appleufs->ul_time    = htobe32((u_int32_t)t);
 156         appleufs->ul_namelen = htobe16(namelen);
 157         strncpy(appleufs->ul_name,name,namelen);
 158         appleufs->ul_uuid    = htobe64(uuid);
 159         appleufs->ul_checksum = ffs_appleufs_cksum(appleufs);
 160 }