usr.sbin/fstyp/ufs.c

   1 /*-
   2  * Copyright (c) 2016 The DragonFly Project
   3  * Copyright (c) 2002, 2003 Gordon Tetlow
   4  * Copyright (c) 2006 Pawel Jakub Dawidek <pjd@FreeBSD.org>
   5  * Copyright (c) 2014 The FreeBSD Foundation
   6  * All rights reserved.
   7  *
   8  * This software was developed by Edward Tomasz Napierala under sponsorship
   9  * from the FreeBSD Foundation.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/types.h>
  35 #include <stdint.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <vfs/ufs/ufs_types.h>
  40 #include <vfs/ufs/fs.h>
  41
  42 #include "fstyp.h"
  43
  44 /*
  45  * Filesystem identification
  46  */
  47 #define FS_UFS1_MAGIC   FS_MAGIC        /* UFS1 fast filesystem magic number */
  48 #define FS_UFS2_MAGIC   0x19540119      /* UFS2 fast filesystem magic number */
  49
  50 #define SBLOCK_FLOPPY        0
  51 #define SBLOCK_UFS1       8192
  52 #define SBLOCK_UFS2      65536
  53 #define SBLOCK_PIGGY    262144
  54 #define SBLOCKSIZE        8192
  55 #define SBLOCKSEARCH    \
  56         { SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 }
  57
  58 static const int superblocks[] = SBLOCKSEARCH;
  59
  60 int
  61 fstyp_ufs(FILE *fp, char *label, size_t labelsize)
  62 {
  63         int sb, superblock;
  64         struct fs *fs;
  65
  66         /*
  67          * Walk through the standard places that superblocks hide and look
  68          * for UFS magic. If we find magic, then check that the size in the
  69          * superblock corresponds to the size of the underlying provider.
  70          * Finally, look for a volume label and create an appropriate
  71          * provider based on that.
  72          */
  73         for (sb = 0; (superblock = superblocks[sb]) != -1; sb++) {
  74                 fs = (struct fs *)read_buf(fp, superblock, SBLOCKSIZE);
  75                 if (fs == NULL)
  76                         continue;
  77                 /*
  78                  * Check for magic. We also need to check if file system size is equal
  79                  * to providers size, because sysinstall(8) used to bogusly put first
  80                  * partition at offset 0 instead of 16, and glabel/ufs would find file
  81                  * system on slice instead of partition.
  82                  */
  83 #ifdef notyet
  84                 if (fs->fs_magic == FS_UFS1_MAGIC && fs->fs_fsize > 0 &&
  85                     ((pp->mediasize / fs->fs_fsize == fs->fs_old_size) ||
  86                     (pp->mediasize / fs->fs_fsize == fs->fs_providersize))) {
  87                         /* Valid UFS1. */
  88                 } else if (fs->fs_magic == FS_UFS2_MAGIC && fs->fs_fsize > 0 &&
  89                     ((pp->mediasize / fs->fs_fsize == fs->fs_size) ||
  90                     (pp->mediasize / fs->fs_fsize == fs->fs_providersize))) {
  91                         /* Valid UFS2. */
  92                 } else {
  93                         g_free(fs);
  94                         continue;
  95                 }
  96 #else
  97                 if (fs->fs_magic == FS_UFS1_MAGIC && fs->fs_fsize > 0) {
  98                         /* Valid UFS1. */
  99                 } else if (fs->fs_magic == FS_UFS2_MAGIC && fs->fs_fsize > 0) {
 100                         /* Valid UFS2. */
 101                 } else {
 102                         free(fs);
 103                         continue;
 104                 }
 105 #endif
 106                 /*
 107                  * XXX: DragonFly
 108                  */
 109                 if (/* fs->fs_sblockloc != superblock || */
 110                     fs->fs_ncg < 1 ||
 111                     fs->fs_bsize < MINBSIZE ||
 112                     (size_t)fs->fs_bsize < sizeof(struct fs)) {
 113                         free(fs);
 114                         continue;
 115                 }
 116
 117                 strlcpy(label, fs->fs_volname, labelsize);
 118
 119                 free(fs);
 120                 return (0);
 121         }
 122
 123         return (1);
 124 }