From: Jose R. Santos <jrs@xxxxxxxxxx>
- Add support for computing CRC-16 value.
- Add call to check/verify/set csum on block_groups.
- Add a test program to verify csum operations.
Signed-off-by: Jose R. Santos <jrs@xxxxxxxxxx>
Signed-off-by: Andreas Dilger <adilger@xxxxxxxxxxxxx>
Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx>
---
lib/ext2fs/Makefile.in | 21 ++++++-
lib/ext2fs/crc16.c | 61 ++++++++++++++++++
lib/ext2fs/crc16.h | 45 +++++++++++++
lib/ext2fs/csum.c | 162 ++++++++++++++++++++++++++++++++++++++++++++++++
lib/ext2fs/ext2_fs.h | 1 +
lib/ext2fs/ext2fs.h | 5 ++
lib/ext2fs/tst_csum.c | 130 ++++++++++++++++++++++++++++++++++++++
7 files changed, 423 insertions(+), 2 deletions(-)
create mode 100644 lib/ext2fs/crc16.c
create mode 100644 lib/ext2fs/crc16.h
create mode 100644 lib/ext2fs/csum.c
create mode 100644 lib/ext2fs/tst_csum.c
diff --git a/lib/ext2fs/Makefile.in b/lib/ext2fs/Makefile.in
index 53b738d..f0f02dc 100644
--- a/lib/ext2fs/Makefile.in
+++ b/lib/ext2fs/Makefile.in
@@ -30,6 +30,8 @@ OBJS= $(DEBUGFS_LIB_OBJS) $(RESIZE_LIB_OBJS) $(E2IMAGE_LIB_OBJS) \
bmap.o \
check_desc.o \
closefs.o \
+ crc16.o \
+ csum.o \
dblist.o \
dblist_dir.o \
dirblock.o \
@@ -85,6 +87,8 @@ SRCS= ext2_err.c \
$(srcdir)/bmap.c \
$(srcdir)/check_desc.c \
$(srcdir)/closefs.c \
+ $(srcdir)/crc16.c \
+ $(srcdir)/csum.c \
$(srcdir)/dblist.c \
$(srcdir)/dblist_dir.c \
$(srcdir)/dirblock.c \
@@ -130,6 +134,7 @@ SRCS= ext2_err.c \
$(srcdir)/tst_badblocks.c \
$(srcdir)/tst_bitops.c \
$(srcdir)/tst_byteswap.c \
+ $(srcdir)/tst_csum.c \
$(srcdir)/tst_getsize.c \
$(srcdir)/tst_iscan.c \
$(srcdir)/unix_io.c \
@@ -305,17 +310,23 @@ tst_extents: $(srcdir)/extent.c extent_dbg.c $(DEBUG_OBJS) $(LIBSS) $(LIBE2P) $(
$(LIBUUID) $(STATIC_LIBEXT2FS) $(LIBBLKID) $(LIBCOM_ERR) \
-I $(top_srcdir)/debugfs
+tst_csum: tst_csum.c csum.c $(STATIC_LIBEXT2FS)
+ @echo " LD $@"
+ @$(CC) -o tst_csum $(srcdir)/csum.c $(srcdir)/tst_csum.c -DDEBUG \
+ $(ALL_CFLAGS) $(STATIC_LIBEXT2FS) $(LIBCOM_ERR)
+
mkjournal: mkjournal.c $(STATIC_LIBEXT2FS)
@echo " LD $@"
@$(CC) -o mkjournal $(srcdir)/mkjournal.c -DDEBUG $(STATIC_LIBEXT2FS) $(LIBCOM_ERR) $(ALL_CFLAGS)
-check:: tst_bitops tst_badblocks tst_iscan tst_types tst_icount tst_super_size
+check:: tst_bitops tst_badblocks tst_iscan tst_types tst_icount tst_super_size tst_types tst_csum
LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_bitops
LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_badblocks
LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_iscan
LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_types
LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_icount
LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_super_size
+ LD_LIBRARY_PATH=$(LIB) DYLD_LIBRARY_PATH=$(LIB) ./tst_csum
installdirs::
@echo " MKINSTALLDIRS $(libdir) $(includedir)/ext2fs"
@@ -347,7 +358,7 @@ clean::
$(RM) -f \#* *.s *.o *.a *~ *.bak core profiled/* checker/* \
tst_badblocks tst_iscan ext2_err.et ext2_err.c ext2_err.h \
tst_byteswap tst_ismounted tst_getsize tst_sectgetsize \
- tst_bitops tst_types tst_icount tst_super_size \
+ tst_bitops tst_types tst_icount tst_super_size tst_csum \
ext2_tdbtool mkjournal debug_cmds.c \
../libext2fs.a ../libext2fs_p.a ../libext2fs_chk.a
@@ -423,6 +434,10 @@ closefs.o: $(srcdir)/closefs.c $(srcdir)/ext2_fs.h \
$(srcdir)/ext2fs.h $(srcdir)/ext2_fs.h $(srcdir)/ext3_extents.h \
$(top_srcdir)/lib/et/com_err.h $(srcdir)/ext2_io.h \
$(top_builddir)/lib/ext2fs/ext2_err.h $(srcdir)/bitops.h
+crc16.o: $(srcdir)/crc16.c $(srcdir)/ext2_fs.h $(srcdir)/crc16.h \
+ $(top_builddir)/lib/ext2fs/ext2_types.h $(srcdir)/ext2fs.h $(srcdir)/ext2_fs.h
+csum.o: $(srcdir)/csum.c $(srcdir)/ext2_fs.h \
+ $(top_builddir)/lib/ext2fs/ext2_types.h $(srcdir)/ext2fs.h $(srcdir)/ext2_fs.h
dblist.o: $(srcdir)/dblist.c $(srcdir)/ext2_fs.h \
$(top_builddir)/lib/ext2fs/ext2_types.h $(srcdir)/ext2fsP.h \
$(srcdir)/ext2fs.h $(srcdir)/ext2_fs.h $(srcdir)/ext3_extents.h \
@@ -637,3 +652,5 @@ tst_iscan.o: $(srcdir)/tst_iscan.c $(srcdir)/ext2_fs.h \
$(top_builddir)/lib/ext2fs/ext2_types.h $(srcdir)/ext2fs.h \
$(srcdir)/ext2_fs.h $(srcdir)/ext3_extents.h $(top_srcdir)/lib/et/com_err.h \
$(srcdir)/ext2_io.h $(top_builddir)/lib/ext2fs/ext2_err.h $(srcdir)/bitops.h
+tst_csum.o: $(srcdir)/tst_csum.c $(srcdir)/ext2_fs.h \
+ $(top_builddir)/lib/ext2fs/ext2_types.h $(srcdir)/ext2fs.h
diff --git a/lib/ext2fs/crc16.c b/lib/ext2fs/crc16.c
new file mode 100644
index 0000000..1b2b8a1
--- /dev/null
+++ b/lib/ext2fs/crc16.c
@@ -0,0 +1,61 @@
+/*
+ * crc16.c
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include "crc16.h"
+
+/** CRC table for the CRC-16. The poly is 0x8005 (x16 + x15 + x2 + 1) */
+__u16 const crc16_table[256] = {
+ 0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
+ 0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
+ 0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
+ 0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
+ 0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
+ 0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
+ 0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
+ 0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
+ 0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
+ 0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
+ 0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
+ 0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
+ 0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
+ 0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
+ 0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
+ 0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
+ 0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
+ 0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
+ 0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
+ 0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
+ 0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
+ 0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
+ 0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
+ 0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
+ 0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
+ 0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
+ 0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
+ 0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
+ 0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
+ 0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
+ 0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
+ 0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
+};
+
+/**
+ * Compute the CRC-16 for the data buffer
+ *
+ * @param crc previous CRC value
+ * @param buffer data pointer
+ * @param len number of bytes in the buffer
+ * @return the updated CRC value
+ */
+crc16_t crc16(crc16_t crc, const void *buffer, unsigned int len)
+{
+ const unsigned char *cp = buffer;
+
+ while (len--)
+ crc = crc16_byte(crc, *cp++);
+ return crc;
+}
diff --git a/lib/ext2fs/crc16.h b/lib/ext2fs/crc16.h
new file mode 100644
index 0000000..ab3f094
--- /dev/null
+++ b/lib/ext2fs/crc16.h
@@ -0,0 +1,45 @@
+/*
+ * crc16.h - CRC-16 routine
+ *
+ * Implements the standard CRC-16:
+ * Width 16
+ * Poly 0x8005 (x16 + x15 + x2 + 1)
+ * Init 0
+ *
+ * Copyright (c) 2005 Ben Gardner <bgardner@xxxxxxxxxx>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#ifndef __CRC16_H
+#define __CRC16_H
+
+#include <ext2fs/ext2_types.h>
+
+extern __u16 const crc16_table[256];
+
+#ifdef WORDS_BIGENDIAN
+/* for an unknown reason, PPC treats __u16 as signed and keeps doing sign
+ * extension on the value. Instead, use only the low 16 bits of an
+ * unsigned int for holding the CRC value to avoid this.
+ */
+typedef unsigned crc16_t;
+
+static inline crc16_t crc16_byte(crc16_t crc, const unsigned char data)
+{
+ return (((crc >> 8) & 0xffU) ^ crc16_table[(crc ^ data) & 0xffU]) &
+ 0x0000ffffU;
+}
+#else
+typedef __u16 crc16_t;
+
+static inline crc16_t crc16_byte(crc16_t crc, const unsigned char data)
+{
+ return (crc >> 8) ^ crc16_table[(crc ^ data) & 0xff];
+}
+#endif
+
+extern crc16_t crc16(crc16_t crc, const void *buffer, unsigned int len);
+
+#endif /* __CRC16_H */
diff --git a/lib/ext2fs/csum.c b/lib/ext2fs/csum.c
new file mode 100644
index 0000000..c35d924
--- /dev/null
+++ b/lib/ext2fs/csum.c
@@ -0,0 +1,162 @@
+/*
+ * csum.c --- checksumming of ext3 structures
+ *
+ * Copyright (C) 2006 Cluster File Systems, Inc.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+#include "crc16.h"
+#include <assert.h>
+
+#ifndef offsetof
+#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+#endif
+
+#ifdef DEBUG
+#define STATIC
+#else
+#define STATIC static
+#endif
+
+STATIC __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group)
+{
+ __u16 crc = 0;
+ struct ext2_group_desc *desc;
+
+ desc = &fs->group_desc[group];
+
+ if (fs->super->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
+ int offset = offsetof(struct ext2_group_desc, bg_checksum);
+
+#ifdef WORDS_BIGENDIAN
+ struct ext2_group_desc swabdesc = *desc;
+
+ /* Have to swab back to little-endian to do the checksum */
+ ext2fs_swap_group_desc(&swabdesc);
+ desc = &swabdesc;
+
+ group = ext2fs_swab32(group);
+#endif
+ crc = crc16(~0, fs->super->s_uuid, sizeof(fs->super->s_uuid));
+ crc = crc16(crc, &group, sizeof(group));
+ crc = crc16(crc, desc, offset);
+ offset += sizeof(desc->bg_checksum); /* skip checksum */
+ assert(offset == sizeof(*desc));
+ /* for checksum of struct ext4_group_desc do the rest...*/
+ if (offset < fs->super->s_desc_size) {
+ crc = crc16(crc, (char *)desc + offset,
+ fs->super->s_desc_size - offset);
+ }
+ }
+
+ return crc;
+}
+
+int ext2fs_group_desc_csum_verify(ext2_filsys fs, dgrp_t group)
+{
+ if (fs->group_desc[group].bg_checksum !=
+ ext2fs_group_desc_csum(fs, group))
+ return 0;
+
+ return 1;
+}
+
+void ext2fs_group_desc_csum_set(ext2_filsys fs, dgrp_t group)
+{
+ fs->group_desc[group].bg_checksum = ext2fs_group_desc_csum(fs, group);
+}
+
+static __u32 find_last_inode_ingrp(ext2fs_inode_bitmap bitmap,
+ __u32 inodes_per_grp, dgrp_t grp_no)
+{
+ ext2_ino_t i, start_ino, end_ino;
+
+ start_ino = grp_no * inodes_per_grp + 1;
+ end_ino = start_ino + inodes_per_grp - 1;
+
+ for (i = end_ino; i >= start_ino; i--) {
+ if (ext2fs_fast_test_inode_bitmap(bitmap, i))
+ return i - start_ino + 1;
+ }
+ return inodes_per_grp;
+}
+
+/* update the bitmap flags, set the itable high watermark, and calculate
+ * checksums for the group descriptors */
+void ext2fs_set_gdt_csum(ext2_filsys fs)
+{
+ struct ext2_super_block *sb = fs->super;
+ struct ext2_group_desc *bg = fs->group_desc;
+ int blks, csum_flag, dirty = 0;
+ dgrp_t i;
+
+ csum_flag = EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_GDT_CSUM);
+ if (!EXT2_HAS_COMPAT_FEATURE(fs->super,
+ EXT2_FEATURE_COMPAT_LAZY_BG) && !csum_flag)
+ return;
+
+ for (i = 0; i < fs->group_desc_count; i++, bg++) {
+ int old_csum = bg->bg_checksum;
+
+ /* Even if it wasn't zeroed, by the time this function is
+ * called by e2fsck we have already scanned and corrected
+ * the whole inode table so we may as well not overwrite it.
+ * This is just a hint to the kernel that it could do lazy
+ * zeroing of the inode table if mke2fs didn't do it, to help
+ * out if we need to do a full itable scan sometime later. */
+ if (!(bg->bg_flags & (EXT2_BG_INODE_UNINIT |
+ EXT2_BG_INODE_ZEROED))) {
+ fs->group_desc[i].bg_flags |= EXT2_BG_INODE_ZEROED;
+ dirty = 1;
+ }
+
+ if (bg->bg_free_inodes_count == sb->s_inodes_per_group &&
+ i > 0 && (i < fs->group_desc_count - 1 || csum_flag)) {
+ if (!(bg->bg_flags & EXT2_BG_INODE_UNINIT)) {
+ bg->bg_flags |= EXT2_BG_INODE_UNINIT;
+ dirty = 1;
+ }
+ if (csum_flag) {
+ int old_unused = bg->bg_itable_unused;
+ bg->bg_itable_unused = sb->s_inodes_per_group;
+ if (old_unused != bg->bg_itable_unused)
+ dirty = 1;
+ }
+ } else if (csum_flag) {
+ int old_unused = bg->bg_itable_unused;
+ bg->bg_flags &= ~EXT2_BG_INODE_UNINIT;
+ bg->bg_itable_unused = sb->s_inodes_per_group -
+ find_last_inode_ingrp(fs->inode_map,
+ sb->s_inodes_per_group,i);
+ if (old_unused != bg->bg_itable_unused)
+ dirty = 1;
+ }
+
+ /* skip first and last groups, or groups with GDT backups
+ * because the resize inode has blocks allocated in them. */
+ if (i == 0 || (i == fs->group_desc_count - 1 && !csum_flag) ||
+ (ext2fs_bg_has_super(fs, i) && sb->s_reserved_gdt_blocks))
+ goto checksum;
+
+ blks = ext2fs_super_and_bgd_loc(fs, i, 0, 0, 0, 0);
+ if (bg->bg_free_blocks_count == blks &&
+ bg->bg_flags & EXT2_BG_INODE_UNINIT &&
+ !(bg->bg_flags & EXT2_BG_BLOCK_UNINIT)) {
+ bg->bg_flags |= EXT2_BG_BLOCK_UNINIT;
+ dirty = 1;
+ }
+checksum:
+ ext2fs_group_desc_csum_set(fs, i);
+ if (old_csum != bg->bg_checksum)
+ dirty = 1;
+ }
+ if (dirty)
+ ext2fs_mark_super_dirty(fs);
+}
diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h
index 6016b68..1188557 100644
--- a/lib/ext2fs/ext2_fs.h
+++ b/lib/ext2fs/ext2_fs.h
@@ -173,6 +173,7 @@ struct ext4_group_desc
#define EXT2_BG_INODE_UNINIT 0x0001 /* Inode table/bitmap not initialized */
#define EXT2_BG_BLOCK_UNINIT 0x0002 /* Block bitmap not initialized */
+#define EXT2_BG_INODE_ZEROED 0x0004 /* On-disk itable initialized to zero */
/*
* Data structures used by the directory indexing feature
diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index 15f4352..fbea854 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -706,6 +706,11 @@ extern int ext2fs_super_and_bgd_loc(ext2_filsys fs,
int *ret_meta_bg);
extern void ext2fs_update_dynamic_rev(ext2_filsys fs);
+/* csum.c */
+extern void ext2fs_group_desc_csum_set(ext2_filsys fs, dgrp_t group);
+extern int ext2fs_group_desc_csum_verify(ext2_filsys fs, dgrp_t group);
+extern void ext2fs_set_gdt_csum(ext2_filsys fs);
+
/* dblist.c */
extern errcode_t ext2fs_get_num_dirs(ext2_filsys fs, ext2_ino_t *ret_num_dirs);
diff --git a/lib/ext2fs/tst_csum.c b/lib/ext2fs/tst_csum.c
new file mode 100644
index 0000000..e3fa9be
--- /dev/null
+++ b/lib/ext2fs/tst_csum.c
@@ -0,0 +1,130 @@
+/*
+ * This testing program verifies checksumming operations
+ *
+ * Copyright (C) 2006, 2007 by Andreas Dilger <adilger@xxxxxxxxxxxxx>
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include "ext2fs/ext2_fs.h"
+#include "ext2fs/ext2fs.h"
+
+#ifndef offsetof
+#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+#endif
+
+void print_csum(const char *msg, ext2_filsys fs, dgrp_t group)
+{
+ __u16 crc1, crc2, crc3;
+ dgrp_t swabgroup;
+ struct ext2_group_desc *desc = &fs->group_desc[group];
+ struct ext2_super_block *sb = fs->super;
+
+#ifdef WORDS_BIGENDIAN
+ struct ext2_group_desc swabdesc = fs->group_desc[group];
+
+ /* Have to swab back to little-endian to do the checksum */
+ ext2fs_swap_group_desc(&swabdesc);
+ desc = &swabdesc;
+
+ swabgroup = ext2fs_swab32(group);
+#else
+ swabgroup = group;
+#endif
+
+ crc1 = crc16(~0, sb->s_uuid, sizeof(fs->super->s_uuid));
+ crc2 = crc16(crc1, &swabgroup, sizeof(swabgroup));
+ crc3 = crc16(crc2, desc, offsetof(struct ext2_group_desc, bg_checksum));
+ printf("%s: UUID %016Lx%016Lx(%04x), grp %u(%04x): %04x=%04x\n",
+ msg, *(long long *)&sb->s_uuid, *(long long *)&sb->s_uuid[8],
+ crc1, group, crc2, crc3, ext2fs_group_desc_csum(fs, group));
+}
+
+unsigned char sb_uuid[16] = { 0x4f, 0x25, 0xe8, 0xcf, 0xe7, 0x97, 0x48, 0x23,
+ 0xbe, 0xfa, 0xa7, 0x88, 0x4b, 0xae, 0xec, 0xdb };
+
+main(int argc, char **argv)
+{
+ struct ext2_super_block param;
+ errcode_t retval;
+ ext2_filsys fs;
+ int i;
+ __u16 csum1, csum2, csum_known = 0xd3a4;
+
+ memset(¶m, 0, sizeof(param));
+ param.s_blocks_count = 32768;
+
+ retval = ext2fs_initialize("test fs", 0, ¶m,
+ test_io_manager, &fs);
+ if (retval) {
+ com_err("setup", retval,
+ "While initializing filesystem");
+ exit(1);
+ }
+ memcpy(fs->super->s_uuid, sb_uuid, 16);
+ fs->super->s_feature_ro_compat = EXT4_FEATURE_RO_COMPAT_GDT_CSUM;
+
+ for (i=0; i < fs->group_desc_count; i++) {
+ fs->group_desc[i].bg_block_bitmap = 124;
+ fs->group_desc[i].bg_inode_bitmap = 125;
+ fs->group_desc[i].bg_inode_table = 126;
+ fs->group_desc[i].bg_free_blocks_count = 31119;
+ fs->group_desc[i].bg_free_inodes_count = 15701;
+ fs->group_desc[i].bg_used_dirs_count = 2;
+ fs->group_desc[i].bg_flags = 0;
+ };
+
+ csum1 = ext2fs_group_desc_csum(fs, 0);
+ print_csum("csum0000", fs, 0);
+
+#ifdef WORDS_BIGENDIAN
+ csum_known = ext2fs_swab16(known);
+#endif
+ if (csum1 != csum_known) {
+ printf("checksum for group 0 should be %04x\n", csum_known);
+ exit(1);
+ }
+ csum2 = ext2fs_group_desc_csum(fs, 1);
+ print_csum("csum0001", fs, 1);
+ if (csum1 == csum2) {
+ printf("checksums for different groups shouldn't match\n");
+ exit(1);
+ }
+ csum2 = ext2fs_group_desc_csum(fs, 2);
+ print_csum("csumffff", fs, 2);
+ if (csum1 == csum2) {
+ printf("checksums for different groups shouldn't match\n");
+ exit(1);
+ }
+ fs->group_desc[0].bg_checksum = csum1;
+ csum2 = ext2fs_group_desc_csum(fs, 0);
+ print_csum("csum_set", fs, 0);
+ if (csum1 != csum2) {
+ printf("checksums should not depend on checksum field\n");
+ exit(1);
+ }
+ if (!ext2fs_group_desc_csum_verify(fs, 0)) {
+ printf("checksums should verify against gd_checksum\n");
+ exit(1);
+ }
+ memset(fs->super->s_uuid, 0x30, sizeof(fs->super->s_uuid));
+ print_csum("new_uuid", fs, 0);
+ if (ext2fs_group_desc_csum_verify(fs, 0) != 0) {
+ printf("checksums for different filesystems shouldn't match\n");
+ exit(1);
+ }
+ csum1 = fs->group_desc[0].bg_checksum = ext2fs_group_desc_csum(fs, 0);
+ print_csum("csum_new", fs, 0);
+ fs->group_desc[0].bg_free_blocks_count = 1;
+ csum2 = ext2fs_group_desc_csum(fs, 0);
+ print_csum("csum_blk", fs, 0);
+ if (csum1 == csum2) {
+ printf("checksums for different data shouldn't match\n");
+ exit(1);
+ }
+
+ return 0;
+}
--
1.5.4.1.144.gdfee-dirty
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