| bigbiff bigbiff | e60683a | 2013-02-22 20:55:50 -0500 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 1999 by Andries Brouwer |
| 3 | * Copyright (C) 1999, 2000, 2003 by Theodore Ts'o |
| 4 | * Copyright (C) 2001 by Andreas Dilger |
| 5 | * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> |
| 6 | * Copyright (C) 2008 Karel Zak <kzak@redhat.com> |
| 7 | * |
| 8 | * This file may be redistributed under the terms of the |
| 9 | * GNU Lesser General Public License. |
| 10 | */ |
| 11 | |
| 12 | #include <string.h> |
| 13 | #include "superblocks.h" |
| 14 | #include "minix.h" |
| 15 | |
| 16 | static int probe_minix(blkid_probe pr, const struct blkid_idmag *mag) |
| 17 | { |
| 18 | unsigned char *ext; |
| 19 | int version; |
| 20 | |
| 21 | /* for more details see magic strings below */ |
| 22 | switch(mag->magic[1]) { |
| 23 | case '\023': |
| 24 | version = 1; |
| 25 | break; |
| 26 | case '\044': |
| 27 | version = 2; |
| 28 | break; |
| 29 | case '\115': |
| 30 | version = 3; |
| 31 | break; |
| 32 | default: |
| 33 | return -1; |
| 34 | break; |
| 35 | } |
| 36 | |
| 37 | if (version <= 2) { |
| 38 | struct minix_super_block *sb; |
| 39 | uint32_t zones; |
| 40 | |
| 41 | sb = blkid_probe_get_sb(pr, mag, struct minix_super_block); |
| 42 | if (!sb || sb->s_imap_blocks == 0 || sb->s_zmap_blocks == 0) |
| 43 | return -1; |
| 44 | |
| 45 | zones = version == 2 ? sb->s_zones : sb->s_nzones; |
| 46 | |
| 47 | /* sanity checks to be sure that the FS is really minix */ |
| 48 | if (sb->s_imap_blocks * MINIX_BLOCK_SIZE * 8 < sb->s_ninodes + 1) |
| 49 | return -1; |
| 50 | if (sb->s_zmap_blocks * MINIX_BLOCK_SIZE * 8 < zones - sb->s_firstdatazone + 1) |
| 51 | return -1; |
| 52 | |
| 53 | } else if (version == 3) { |
| 54 | struct minix3_super_block *sb; |
| 55 | |
| 56 | sb = blkid_probe_get_sb(pr, mag, struct minix3_super_block); |
| 57 | if (!sb || sb->s_imap_blocks == 0 || sb->s_zmap_blocks == 0) |
| 58 | return -1; |
| 59 | |
| 60 | } |
| 61 | |
| 62 | /* unfortunately, some parts of ext3 is sometimes possible to |
| 63 | * interpreted as minix superblock. So check for extN magic |
| 64 | * string. (For extN magic string and offsets see ext.c.) |
| 65 | */ |
| 66 | ext = blkid_probe_get_buffer(pr, 0x400 + 0x38, 2); |
| 67 | if (ext && memcmp(ext, "\123\357", 2) == 0) |
| 68 | return -1; |
| 69 | |
| 70 | blkid_probe_sprintf_version(pr, "%d", version); |
| 71 | return 0; |
| 72 | } |
| 73 | |
| 74 | const struct blkid_idinfo minix_idinfo = |
| 75 | { |
| 76 | .name = "minix", |
| 77 | .usage = BLKID_USAGE_FILESYSTEM, |
| 78 | .probefunc = probe_minix, |
| 79 | .magics = |
| 80 | { |
| 81 | /* version 1 */ |
| 82 | { .magic = "\177\023", .len = 2, .kboff = 1, .sboff = 0x10 }, |
| 83 | { .magic = "\217\023", .len = 2, .kboff = 1, .sboff = 0x10 }, |
| 84 | |
| 85 | /* version 2 */ |
| 86 | { .magic = "\150\044", .len = 2, .kboff = 1, .sboff = 0x10 }, |
| 87 | { .magic = "\170\044", .len = 2, .kboff = 1, .sboff = 0x10 }, |
| 88 | |
| 89 | /* version 3 */ |
| 90 | { .magic = "\132\115", .len = 2, .kboff = 1, .sboff = 0x18 }, |
| 91 | { NULL } |
| 92 | } |
| 93 | }; |
| 94 | |