1 files changed, 445 insertions, 0 deletions
diff --git a/usr/kinit/fstype/fstype.c b/usr/kinit/fstype/fstype.c
new file mode 100644
index 0000000..aebccca
--- /dev/null
+++ b/usr/kinit/fstype/fstype.c
@@ -0,0 +1,445 @@
+/*
+ * by rmk
+ *
+ * Detect filesystem type (on stdin) and output strings for two
+ * environment variables:
+ *  FSTYPE - filesystem type
+ *  FSSIZE - filesystem size (if known)
+ *
+ * We currently detect the filesystems listed below in the struct
+ * "imagetype images" (in the order they are listed).
+ */
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <endian.h>
+#include <netinet/in.h>
+#include <sys/utsname.h>
+#include <sys/vfs.h>
+
+#define cpu_to_be32(x) __cpu_to_be32(x)	/* Needed by romfs_fs.h */
+
+#include "btrfs.h"
+#include "cramfs_fs.h"
+#include "ext2_fs.h"
+#include "ext3_fs.h"
+#include "gfs2_fs.h"
+#include "iso9660_sb.h"
+#include "luks_fs.h"
+#include "lvm2_sb.h"
+#include "minix_fs.h"
+#include "nilfs_fs.h"
+#include "ocfs2_fs.h"
+#include "romfs_fs.h"
+#include "squashfs_fs.h"
+#include "xfs_sb.h"
+
+/*
+ * Slightly cleaned up version of jfs_superblock to
+ * avoid pulling in other kernel header files.
+ */
+#include "jfs_superblock.h"
+
+/*
+ * reiserfs_fs.h is too sick to include directly.
+ * Use a cleaned up version.
+ */
+#include "reiserfs_fs.h"
+#include "reiser4_fs.h"
+
+#include "fstype.h"
+
+#define ARRAY_SIZE(x)	(sizeof(x) / sizeof(x[0]))
+
+#define BLOCK_SIZE 1024
+
+/* Swap needs the definition of block size */
+#include "swap_fs.h"
+
+static int gzip_image(const void *buf, unsigned long long *bytes)
+{
+	const unsigned char *p = buf;
+
+	if (p[0] == 037 && (p[1] == 0213 || p[1] == 0236)) {
+		/* The length of a gzip stream can only be determined
+		   by processing the whole stream */
+		*bytes = 0ULL;
+		return 1;
+	}
+	return 0;
+}
+
+static int cramfs_image(const void *buf, unsigned long long *bytes)
+{
+	const struct cramfs_super *sb = (const struct cramfs_super *)buf;
+
+	if (sb->magic == CRAMFS_MAGIC) {
+		if (sb->flags & CRAMFS_FLAG_FSID_VERSION_2)
+			*bytes = (unsigned long long)sb->fsid.blocks << 10;
+		else
+			*bytes = 0;
+		return 1;
+	}
+	return 0;
+}
+
+static int romfs_image(const void *buf, unsigned long long *bytes)
+{
+	const struct romfs_super_block *sb =
+	    (const struct romfs_super_block *)buf;
+
+	if (sb->word0 == ROMSB_WORD0 && sb->word1 == ROMSB_WORD1) {
+		*bytes = __be32_to_cpu(sb->size);
+		return 1;
+	}
+	return 0;
+}
+
+static int minix_image(const void *buf, unsigned long long *bytes)
+{
+	const struct minix_super_block *sb =
+	    (const struct minix_super_block *)buf;
+
+	if (sb->s_magic == MINIX_SUPER_MAGIC ||
+	    sb->s_magic == MINIX_SUPER_MAGIC2) {
+		*bytes = (unsigned long long)sb->s_nzones
+		    << (sb->s_log_zone_size + 10);
+		return 1;
+	}
+	return 0;
+}
+
+static int ext4_image(const void *buf, unsigned long long *bytes)
+{
+	const struct ext3_super_block *sb =
+		(const struct ext3_super_block *)buf;
+
+	if (sb->s_magic != __cpu_to_le16(EXT2_SUPER_MAGIC))
+		return 0;
+
+	/* There is at least one feature not supported by ext3 */
+	if ((sb->s_feature_incompat
+	     & __cpu_to_le32(EXT3_FEATURE_INCOMPAT_UNSUPPORTED)) ||
+	    (sb->s_feature_ro_compat
+	     & __cpu_to_le32(EXT3_FEATURE_RO_COMPAT_UNSUPPORTED))) {
+		*bytes = (unsigned long long)__le32_to_cpu(sb->s_blocks_count)
+			<< (10 + __le32_to_cpu(sb->s_log_block_size));
+		return 1;
+	}
+	return 0;
+}
+
+static int ext3_image(const void *buf, unsigned long long *bytes)
+{
+	const struct ext3_super_block *sb =
+	    (const struct ext3_super_block *)buf;
+
+	if (sb->s_magic == __cpu_to_le16(EXT2_SUPER_MAGIC) &&
+	    sb->
+	    s_feature_compat & __cpu_to_le32(EXT3_FEATURE_COMPAT_HAS_JOURNAL)) {
+		*bytes = (unsigned long long)__le32_to_cpu(sb->s_blocks_count)
+		    << (10 + __le32_to_cpu(sb->s_log_block_size));
+		return 1;
+	}
+	return 0;
+}
+
+static int ext2_image(const void *buf, unsigned long long *bytes)
+{
+	const struct ext2_super_block *sb =
+	    (const struct ext2_super_block *)buf;
+
+	if (sb->s_magic == __cpu_to_le16(EXT2_SUPER_MAGIC)) {
+		*bytes = (unsigned long long)__le32_to_cpu(sb->s_blocks_count)
+		    << (10 + __le32_to_cpu(sb->s_log_block_size));
+		return 1;
+	}
+	return 0;
+}
+
+static int reiserfs_image(const void *buf, unsigned long long *bytes)
+{
+	const struct reiserfs_super_block *sb =
+	    (const struct reiserfs_super_block *)buf;
+
+	if (memcmp(REISERFS_MAGIC(sb), REISERFS_SUPER_MAGIC_STRING,
+		   sizeof(REISERFS_SUPER_MAGIC_STRING) - 1) == 0 ||
+	    memcmp(REISERFS_MAGIC(sb), REISER2FS_SUPER_MAGIC_STRING,
+		   sizeof(REISER2FS_SUPER_MAGIC_STRING) - 1) == 0 ||
+	    memcmp(REISERFS_MAGIC(sb), REISER2FS_JR_SUPER_MAGIC_STRING,
+		   sizeof(REISER2FS_JR_SUPER_MAGIC_STRING) - 1) == 0) {
+		*bytes = (unsigned long long)REISERFS_BLOCK_COUNT(sb) *
+		    REISERFS_BLOCKSIZE(sb);
+		return 1;
+	}
+	return 0;
+}
+
+static int reiser4_image(const void *buf, unsigned long long *bytes)
+{
+	const struct reiser4_master_sb *sb =
+		(const struct reiser4_master_sb *)buf;
+
+	if (memcmp(sb->ms_magic, REISER4_SUPER_MAGIC_STRING,
+		sizeof(REISER4_SUPER_MAGIC_STRING) - 1) == 0) {
+		*bytes = (unsigned long long) __le32_to_cpu(sb->ms_format) *
+			__le32_to_cpu(sb->ms_blksize);
+		return 1;
+	}
+	return 0;
+}
+
+static int xfs_image(const void *buf, unsigned long long *bytes)
+{
+	const struct xfs_sb *sb = (const struct xfs_sb *)buf;
+
+	if (__be32_to_cpu(sb->sb_magicnum) == XFS_SB_MAGIC) {
+		*bytes = __be64_to_cpu(sb->sb_dblocks) *
+		    __be32_to_cpu(sb->sb_blocksize);
+		return 1;
+	}
+	return 0;
+}
+
+static int jfs_image(const void *buf, unsigned long long *bytes)
+{
+	const struct jfs_superblock *sb = (const struct jfs_superblock *)buf;
+
+	if (!memcmp(sb->s_magic, JFS_MAGIC, 4)) {
+		*bytes = __le64_to_cpu(sb->s_size)
+			<< __le16_to_cpu(sb->s_l2pbsize);
+		return 1;
+	}
+	return 0;
+}
+
+static int luks_image(const void *buf, unsigned long long *blocks)
+{
+	const struct luks_partition_header *lph =
+	    (const struct luks_partition_header *)buf;
+
+	if (!memcmp(lph->magic, LUKS_MAGIC, LUKS_MAGIC_L)) {
+		/* FSSIZE is dictated by the underlying fs, not by LUKS */
+		*blocks = 0;
+		return 1;
+	}
+	return 0;
+}
+
+static int swap_image(const void *buf, unsigned long long *blocks)
+{
+	const struct swap_super_block *ssb =
+	    (const struct swap_super_block *)buf;
+
+	if (!memcmp(ssb->magic, SWAP_MAGIC_1, SWAP_MAGIC_L) ||
+	    !memcmp(ssb->magic, SWAP_MAGIC_2, SWAP_MAGIC_L)) {
+		*blocks = 0;
+		return 1;
+	}
+	return 0;
+}
+
+static int suspend_image(const void *buf, unsigned long long *blocks)
+{
+	const struct swap_super_block *ssb =
+	    (const struct swap_super_block *)buf;
+
+	if (!memcmp(ssb->magic, SUSP_MAGIC_1, SUSP_MAGIC_L) ||
+	    !memcmp(ssb->magic, SUSP_MAGIC_2, SUSP_MAGIC_L) ||
+	    !memcmp(ssb->magic, SUSP_MAGIC_U, SUSP_MAGIC_L)) {
+		*blocks = 0;
+		return 1;
+	}
+	return 0;
+}
+
+static int lvm2_image(const void *buf, unsigned long long *blocks)
+{
+	const struct lvm2_super_block *lsb;
+	int i;
+
+	/* We must check every 512 byte sector */
+	for (i = 0; i < BLOCK_SIZE; i += 0x200) {
+		lsb = (const struct lvm2_super_block *)(buf + i);
+
+		if (!memcmp(lsb->magic, LVM2_MAGIC, LVM2_MAGIC_L) &&
+		    !memcmp(lsb->type, LVM2_TYPE, LVM2_TYPE_L)) {
+			/* This is just one of possibly many PV's */
+			*blocks = 0;
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+static int iso_image(const void *buf, unsigned long long *blocks)
+{
+	const struct iso_volume_descriptor *isovd =
+	    (const struct iso_volume_descriptor *)buf;
+	const struct iso_hs_volume_descriptor *isohsvd =
+	    (const struct iso_hs_volume_descriptor *)buf;
+
+	if (!memcmp(isovd->id, ISO_MAGIC, ISO_MAGIC_L) ||
+	    !memcmp(isohsvd->id, ISO_HS_MAGIC, ISO_HS_MAGIC_L)) {
+		*blocks = 0;
+		return 1;
+	}
+	return 0;
+}
+
+static int squashfs_image(const void *buf, unsigned long long *blocks)
+{
+	const struct squashfs_super_block *sb =
+		(const struct squashfs_super_block *)buf;
+
+	if (sb->s_magic == SQUASHFS_MAGIC
+	    || sb->s_magic == SQUASHFS_MAGIC_SWAP
+	    || sb->s_magic == SQUASHFS_MAGIC_LZMA
+	    || sb->s_magic == SQUASHFS_MAGIC_LZMA_SWAP) {
+		*blocks = (unsigned long long) sb->bytes_used;
+		return 1;
+	}
+	return 0;
+}
+
+static int gfs2_image(const void *buf, unsigned long long *bytes)
+{
+	const struct gfs2_sb *sb =
+		(const struct gfs2_sb *)buf;
+
+	if (__be32_to_cpu(sb->sb_header.mh_magic) == GFS2_MAGIC
+		&& (__be32_to_cpu(sb->sb_fs_format) == GFS2_FORMAT_FS
+		|| __be32_to_cpu(sb->sb_fs_format) == GFS2_FORMAT_MULTI)) {
+		*bytes = 0; /* cpu_to_be32(sb->sb_bsize) * ?; */
+		return 1;
+	}
+	return 0;
+}
+
+static int ocfs2_image(const void *buf, unsigned long long *bytes)
+{
+	const struct ocfs2_dinode *sb =
+		(const struct ocfs2_dinode *)buf;
+
+	if (!memcmp(sb->i_signature, OCFS2_SUPER_BLOCK_SIGNATURE,
+			sizeof(OCFS2_SUPER_BLOCK_SIGNATURE) - 1)) {
+		*bytes = 0;
+		return 1;
+	}
+	return 0;
+}
+
+static int nilfs2_image(const void *buf, unsigned long long *bytes)
+{
+	const struct nilfs_super_block *sb =
+	    (const struct nilfs_super_block *)buf;
+
+	if (sb->s_magic == __cpu_to_le16(NILFS_SUPER_MAGIC) &&
+	    sb->s_rev_level == __cpu_to_le32(2)) {
+		*bytes = (unsigned long long)__le64_to_cpu(sb->s_dev_size);
+		return 1;
+	}
+	return 0;
+}
+
+static int btrfs_image(const void *buf, unsigned long long *bytes)
+{
+	const struct btrfs_super_block *sb =
+	    (const struct btrfs_super_block *)buf;
+
+	if (!memcmp(sb->magic, BTRFS_MAGIC, BTRFS_MAGIC_L)) {
+		*bytes = (unsigned long long)__le64_to_cpu(sb->total_bytes);
+		return 1;
+	}
+	return 0;
+}
+
+struct imagetype {
+	off_t block;
+	const char name[12];
+	int (*identify) (const void *, unsigned long long *);
+};
+
+/*
+ * Note:
+ *
+ * Minix test needs to come after ext3/ext2, since it's possible for
+ * ext3/ext2 to look like minix by pure random chance.
+ *
+ * LVM comes after all other filesystems since it's possible
+ * that an old lvm signature is left on the disk if pvremove
+ * is not used before creating the new fs.
+ *
+ * The same goes for LUKS as for LVM.
+ */
+static struct imagetype images[] = {
+	{0, "gzip", gzip_image},
+	{0, "cramfs", cramfs_image},
+	{0, "romfs", romfs_image},
+	{0, "xfs", xfs_image},
+	{0, "squashfs", squashfs_image},
+	{1, "ext4", ext4_image},
+	{1, "ext3", ext3_image},
+	{1, "ext2", ext2_image},
+	{1, "minix", minix_image},
+	{1, "nilfs2", nilfs2_image},
+	{2, "ocfs2", ocfs2_image},
+	{8, "reiserfs", reiserfs_image},
+	{64, "reiserfs", reiserfs_image},
+	{64, "reiser4", reiser4_image},
+	{64, "gfs2", gfs2_image},
+	{64, "btrfs", btrfs_image},
+	{32, "jfs", jfs_image},
+	{32, "iso9660", iso_image},
+	{0, "luks", luks_image},
+	{0, "lvm2", lvm2_image},
+	{1, "lvm2", lvm2_image},
+	{-1, "swap", swap_image},
+	{-1, "suspend", suspend_image},
+	{0, "", NULL}
+};
+
+int identify_fs(int fd, const char **fstype,
+		unsigned long long *bytes, off_t offset)
+{
+	uint64_t buf[BLOCK_SIZE >> 3];	/* 64-bit worst case alignment */
+	off_t cur_block = (off_t) -1;
+	struct imagetype *ip;
+	int ret;
+	unsigned long long dummy;
+
+	if (!bytes)
+		bytes = &dummy;
+
+	*fstype = NULL;
+	*bytes = 0;
+
+	for (ip = images; ip->identify; ip++) {
+		/* Hack for swap, which apparently is dependent on page size */
+		if (ip->block == -1)
+			ip->block = SWAP_OFFSET();
+
+		if (cur_block != ip->block) {
+			/*
+			 * Read block.
+			 */
+			cur_block = ip->block;
+			ret = pread(fd, buf, BLOCK_SIZE,
+				    offset + cur_block * BLOCK_SIZE);
+			if (ret != BLOCK_SIZE)
+				return -1;	/* error */
+		}
+
+		if (ip->identify(buf, bytes)) {
+			*fstype = ip->name;
+			return 0;
+		}
+	}
+
+	return 1;		/* Unknown filesystem */
+}