sys/ufs/ffs/ffs_appleufs.c

   1 /*      $NetBSD: ffs_appleufs.c,v 1.12 2011/11/19 22:51:31 tls Exp $    */
   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  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __KERNEL_RCSID(0, "$NetBSD: ffs_appleufs.c,v 1.12 2011/11/19 22:51:31 tls Exp $");
  30
  31 #include <sys/param.h>
  32 #include <sys/time.h>
  33 #if defined(_KERNEL)
  34 #include <sys/kernel.h>
  35 #include <sys/systm.h>
  36 #include <sys/cprng.h>
  37 #endif
  38
  39 #include <ufs/ufs/dinode.h>
  40 #include <ufs/ufs/ufs_bswap.h>
  41 #include <ufs/ffs/fs.h>
  42 #include <ufs/ffs/ffs_extern.h>
  43
  44 #if !defined(_KERNEL) && !defined(STANDALONE)
  45 #include <stddef.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49 #include <errno.h>
  50 #include <assert.h>
  51 #define KASSERT(x) assert(x)
  52 #endif
  53
  54 /*
  55  * this is the same calculation as in_cksum
  56  */
  57 u_int16_t
  58 ffs_appleufs_cksum(const struct appleufslabel *appleufs)
  59 {
  60         const u_int16_t *p = (const u_int16_t *)appleufs;
  61         int len = APPLEUFS_LABEL_SIZE; /* sizeof(struct appleufslabel) */
  62         long res = 0;
  63         while (len > 1)  {
  64                 res += *p++;
  65                 len -= 2;
  66         }
  67 #if 0 /* APPLEUFS_LABEL_SIZE is guaranteed to be even */
  68         if (len == 1)
  69                 res += htobe16(*(u_char *)p<<8);
  70 #endif
  71         res = (res >> 16) + (res & 0xffff);
  72         res += (res >> 16);
  73         return (~res);
  74 }
  75
  76 /* copies o to n, validating and byteswapping along the way
  77  * returns 0 if ok, EINVAL if not valid
  78  */
  79 int
  80 ffs_appleufs_validate(const char *name, const struct appleufslabel *o,
  81     struct appleufslabel *n)
  82 {
  83         struct appleufslabel tmp;
  84         if (!n) n = &tmp;
  85
  86         if (o->ul_magic != be32toh(APPLEUFS_LABEL_MAGIC)) {
  87                 return EINVAL;
  88         }
  89         *n = *o;
  90         n->ul_checksum = 0;
  91         n->ul_checksum = ffs_appleufs_cksum(n);
  92         if (n->ul_checksum != o->ul_checksum) {
  93 #if defined(DIAGNOSTIC) || !defined(_KERNEL)
  94                 printf("%s: invalid APPLE UFS checksum. found 0x%x, expecting 0x%x",
  95                         name,o->ul_checksum,n->ul_checksum);
  96 #endif
  97                 return EINVAL;
  98         }
  99         n->ul_magic = be32toh(o->ul_magic);
 100         n->ul_version = be32toh(o->ul_version);
 101         n->ul_time = be32toh(o->ul_time);
 102         n->ul_namelen = be16toh(o->ul_namelen);
 103
 104         if (n->ul_namelen > APPLEUFS_MAX_LABEL_NAME) {
 105 #if defined(DIAGNOSTIC) || !defined(_KERNEL)
 106                 printf("%s: APPLE UFS label name too long, truncated.\n",
 107                                 name);
 108 #endif
 109                 n->ul_namelen = APPLEUFS_MAX_LABEL_NAME;
 110         }
 111         /* if len is max, will set ul_unused1 */
 112         n->ul_name[n->ul_namelen - 1] = '\0';
 113
 114 #ifdef DEBUG
 115         printf("%s: found APPLE UFS label v%d: \"%s\"\n",
 116             name,n->ul_version,n->ul_name);
 117 #endif
 118         n->ul_uuid = be64toh(o->ul_uuid);
 119
 120         return 0;
 121 }
 122
 123 void
 124 ffs_appleufs_set(struct appleufslabel *appleufs, const char *name, time_t t,
 125     uint64_t uuid)
 126 {
 127         size_t namelen;
 128         if (!name) name = "untitled";
 129         if (t == ((time_t)-1)) {
 130 #if defined(_KERNEL)
 131                 t = time_second;
 132 #elif defined(STANDALONE)
 133                 t = 0;
 134 #else
 135                 (void)time(&t);
 136 #endif
 137         }
 138         if (uuid == 0) {
 139 #if defined(_KERNEL) && !defined(STANDALONE)
 140                 uuid = cprng_fast64();
 141 #endif
 142         }
 143         namelen = strlen(name);
 144         if (namelen > APPLEUFS_MAX_LABEL_NAME)
 145                 namelen = APPLEUFS_MAX_LABEL_NAME;
 146         memset(appleufs, 0, APPLEUFS_LABEL_SIZE);
 147         appleufs->ul_magic   = htobe32(APPLEUFS_LABEL_MAGIC);
 148         appleufs->ul_version = htobe32(APPLEUFS_LABEL_VERSION);
 149         appleufs->ul_time    = htobe32((u_int32_t)t);
 150         appleufs->ul_namelen = htobe16(namelen);
 151         strncpy(appleufs->ul_name,name,namelen);
 152         appleufs->ul_uuid    = htobe64(uuid);
 153         appleufs->ul_checksum = ffs_appleufs_cksum(appleufs);
 154 }