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-rw-r--r--libblkid/src/superblocks/minix.c161
1 files changed, 161 insertions, 0 deletions
diff --git a/libblkid/src/superblocks/minix.c b/libblkid/src/superblocks/minix.c
new file mode 100644
index 000000000..9ea49fee8
--- /dev/null
+++ b/libblkid/src/superblocks/minix.c
@@ -0,0 +1,161 @@
+/*
+ * Copyright (C) 1999 by Andries Brouwer
+ * Copyright (C) 1999, 2000, 2003 by Theodore Ts'o
+ * Copyright (C) 2001 by Andreas Dilger
+ * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2008-2013 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ */
+
+#include <string.h>
+#include "superblocks.h"
+#include "minix.h"
+
+#define minix_swab16(doit, num) ((uint16_t) (doit ? swab16(num) : num))
+#define minix_swab32(doit, num) ((uint32_t) (doit ? swab32(num) : num))
+
+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 MINIX2_SUPER_MAGIC:
+ case MINIX2_SUPER_MAGIC2:
+ version = 2;
+ break;
+ default:
+ if (sb3->s_magic == MINIX3_SUPER_MAGIC)
+ version = 3;
+ break;
+ }
+
+ if (!version) {
+ *other_endian = 1;
+
+ 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, ul_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 errno ? -errno : 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 ? 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 (imaps * MINIX_BLOCK_SIZE * 8 < ninodes + 1)
+ return 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 *) data;
+
+ if (sb->s_imap_blocks == 0 || sb->s_zmap_blocks == 0)
+ return 1;
+ }
+
+ /* unfortunately, some parts of ext3 is sometimes possible to
+ * interpreted as minix superblock. So check for extN magic
+ * string. (For extN magic string and offsets see ext.c.)
+ */
+ ext = blkid_probe_get_buffer(pr, 0x400 + 0x38, 2);
+ if (!ext)
+ return errno ? -errno : 1;
+ else if (memcmp(ext, "\123\357", 2) == 0)
+ return 1;
+
+ blkid_probe_sprintf_version(pr, "%d", version);
+ return 0;
+}
+
+const struct blkid_idinfo minix_idinfo =
+{
+ .name = "minix",
+ .usage = BLKID_USAGE_FILESYSTEM,
+ .probefunc = probe_minix,
+ .magics =
+ {
+ /* version 1 - LE */
+ { .magic = "\177\023", .len = 2, .kboff = 1, .sboff = 0x10 },
+ { .magic = "\217\023", .len = 2, .kboff = 1, .sboff = 0x10 },
+
+ /* 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 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 }
+ }
+};
+