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 }
+	}
+};
+