diff --git a/include/minix.h b/include/minix.h index 57be23921..f28991ce9 100644 --- a/include/minix.h +++ b/include/minix.h @@ -73,10 +73,13 @@ struct minix3_super_block { #define MINIX_VALID_FS 0x0001 /* Clean fs. */ #define MINIX_ERROR_FS 0x0002 /* fs has errors. */ -#define MINIX_SUPER_MAGIC 0x137F /* original minix fs */ -#define MINIX_SUPER_MAGIC2 0x138F /* minix fs, 30 char names */ -#define MINIX2_SUPER_MAGIC 0x2468 /* minix V2 fs */ + +#define MINIX_SUPER_MAGIC 0x137F /* minix V1 fs, 14 char names */ +#define MINIX_SUPER_MAGIC2 0x138F /* minix V1 fs, 30 char names */ + +#define MINIX2_SUPER_MAGIC 0x2468 /* minix V2 fs, 14 char names */ #define MINIX2_SUPER_MAGIC2 0x2478 /* minix V2 fs, 30 char names */ + #define MINIX3_SUPER_MAGIC 0x4d5a /* minix V3 fs (60 char names) */ #endif /* UTIL_LINUX_MINIX_H */ diff --git a/libblkid/src/superblocks/minix.c b/libblkid/src/superblocks/minix.c index 54e71396b..0e7cd934f 100644 --- a/libblkid/src/superblocks/minix.c +++ b/libblkid/src/superblocks/minix.c @@ -3,7 +3,7 @@ * Copyright (C) 1999, 2000, 2003 by Theodore Ts'o * Copyright (C) 2001 by Andreas Dilger * Copyright (C) 2004 Kay Sievers - * Copyright (C) 2008 Karel Zak + * Copyright (C) 2008-2013 Karel Zak * * This file may be redistributed under the terms of the * GNU Lesser General Public License. @@ -13,50 +13,103 @@ #include "superblocks.h" #include "minix.h" -static int probe_minix(blkid_probe pr, const struct blkid_idmag *mag) -{ - unsigned char *ext; - int version; +#define minix_swab16(doit, num) ((uint16_t) (doit ? swab16(num) : num)) +#define minix_swab32(doit, num) ((uint32_t) (doit ? swab32(num) : num)) - /* for more details see magic strings below */ - switch(mag->magic[1]) { - case '\023': +static int get_minix_version(const unsigned char *data, int *other_endian) +{ + struct minix_super_block *sb = (struct minix_super_block *) data; + struct minix3_super_block *sb3 = (struct minix3_super_block *) data; + int version = 0; + + *other_endian = 0; + + switch (sb->s_magic) { + case MINIX_SUPER_MAGIC: + case MINIX_SUPER_MAGIC2: version = 1; break; - case '\044': + case MINIX2_SUPER_MAGIC: + case MINIX2_SUPER_MAGIC2: version = 2; break; - case '\115': - version = 3; - break; default: - return -1; + if (sb3->s_magic == MINIX3_SUPER_MAGIC) + version = 3; break; } - if (version <= 2) { - struct minix_super_block *sb; - uint32_t zones; + if (!version) { + *other_endian = 1; - sb = blkid_probe_get_sb(pr, mag, struct minix_super_block); - if (!sb || sb->s_imap_blocks == 0 || sb->s_zmap_blocks == 0) + switch (swab16(sb->s_magic)) { + case MINIX_SUPER_MAGIC: + case MINIX_SUPER_MAGIC2: + version = 1; + break; + case MINIX2_SUPER_MAGIC: + case MINIX2_SUPER_MAGIC2: + version = 2; + break; + default: + if (sb3->s_magic == MINIX3_SUPER_MAGIC) + version = 3; + break; + } + } + if (!version) + return -1; + + DBG(LOWPROBE, blkid_debug("minix version %d detected [%s]", version, +#if defined(WORDS_BIGENDIAN) + *other_endian ? "LE" : "BE" +#else + *other_endian ? "BE" : "LE" +#endif + )); + return version; +} + +static int probe_minix(blkid_probe pr, const struct blkid_idmag *mag) +{ + unsigned char *ext; + const unsigned char *data; + int version = 0, swabme = 0; + + data = blkid_probe_get_buffer(pr, 1024, + max(sizeof(struct minix_super_block), + sizeof(struct minix3_super_block))); + if (!data) + return -1; + version = get_minix_version(data, &swabme); + if (version < 1) + return -1; + + if (version <= 2) { + struct minix_super_block *sb = (struct minix_super_block *) data; + int zones, ninodes, imaps, zmaps, firstz; + + if (sb->s_imap_blocks == 0 || sb->s_zmap_blocks == 0) return -1; - zones = version == 2 ? sb->s_zones : sb->s_nzones; + zones = version == 2 ? minix_swab32(swabme, sb->s_zones) : + minix_swab16(swabme, sb->s_nzones); + ninodes = minix_swab16(swabme, sb->s_ninodes); + imaps = minix_swab16(swabme, sb->s_imap_blocks); + zmaps = minix_swab16(swabme, sb->s_zmap_blocks); + firstz = minix_swab16(swabme, sb->s_firstdatazone); /* sanity checks to be sure that the FS is really minix */ - if (sb->s_imap_blocks * MINIX_BLOCK_SIZE * 8 < sb->s_ninodes + 1) + if (imaps * MINIX_BLOCK_SIZE * 8 < ninodes + 1) return -1; - if (sb->s_zmap_blocks * MINIX_BLOCK_SIZE * 8 < zones - sb->s_firstdatazone + 1) + if (zmaps * MINIX_BLOCK_SIZE * 8 < zones - firstz + 1) return -1; } else if (version == 3) { - struct minix3_super_block *sb; + struct minix3_super_block *sb = (struct minix3_super_block *) data; - sb = blkid_probe_get_sb(pr, mag, struct minix3_super_block); - if (!sb || sb->s_imap_blocks == 0 || sb->s_zmap_blocks == 0) + if (sb->s_imap_blocks == 0 || sb->s_zmap_blocks == 0) return -1; - } /* unfortunately, some parts of ext3 is sometimes possible to @@ -78,16 +131,28 @@ const struct blkid_idinfo minix_idinfo = .probefunc = probe_minix, .magics = { - /* version 1 */ + /* version 1 - LE */ { .magic = "\177\023", .len = 2, .kboff = 1, .sboff = 0x10 }, { .magic = "\217\023", .len = 2, .kboff = 1, .sboff = 0x10 }, - /* version 2 */ + /* version 1 - BE */ + { .magic = "\023\177", .len = 2, .kboff = 1, .sboff = 0x10 }, + { .magic = "\023\217", .len = 2, .kboff = 1, .sboff = 0x10 }, + + /* version 2 - LE */ { .magic = "\150\044", .len = 2, .kboff = 1, .sboff = 0x10 }, { .magic = "\170\044", .len = 2, .kboff = 1, .sboff = 0x10 }, - /* version 3 */ + /* version 2 - BE */ + { .magic = "\044\150", .len = 2, .kboff = 1, .sboff = 0x10 }, + { .magic = "\044\170", .len = 2, .kboff = 1, .sboff = 0x10 }, + + /* version 3 - LE */ { .magic = "\132\115", .len = 2, .kboff = 1, .sboff = 0x18 }, + + /* version 3 - BE */ + { .magic = "\115\132", .len = 2, .kboff = 1, .sboff = 0x18 }, + { NULL } } };