debugfs: teach the htree command to check and display the dx block checksum

To do this we need to export the ext2fs_dx_csum() function from
libext2fs.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/debian/libext2fs2.symbols b/debian/libext2fs2.symbols
index 78c20b2..53cb035 100644 (file)
--- a/debian/libext2fs2.symbols
+++ b/debian/libext2fs2.symbols
@@ -181,6 +181,7 @@ libext2fs.so.2 libext2fs2 #MINVER#
  ext2fs_div_ceil@Base 1.40
  ext2fs_djb2_hash@Base 1.44.3~rc1
  ext2fs_dup_handle@Base 1.37
+ ext2fs_dx_csum@Base 1.46~WIP.2019.10.09
  ext2fs_expand_dir@Base 1.37
  ext2fs_ext_attr_block_csum_set@Base 1.43
  ext2fs_ext_attr_block_csum_verify@Base 1.43

diff --git a/debugfs/htree.c b/debugfs/htree.c
index 3aae3c2..b567a76 100644 (file)
--- a/debugfs/htree.c
+++ b/debugfs/htree.c
@@ -136,7 +136,7 @@ static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 static void htree_dump_int_node(ext2_filsys fs, ext2_ino_t ino,
                                struct ext2_inode *inode,
                                struct ext2_dx_root_info * rootnode,
-                               struct ext2_dx_entry *ent,
+                               struct ext2_dx_entry *ent, __u32 crc,
                                char *buf, int level)
 {
        struct ext2_dx_countlimit       dx_countlimit;
@@ -160,8 +160,11 @@ static void htree_dump_int_node(ext2_filsys fs, ext2_ino_t ino,
        if (ext2fs_has_feature_metadata_csum(fs->super) &&
            remainder == sizeof(struct ext2_dx_tail)) {
                tail = (struct ext2_dx_tail *)(ent + limit);
-               fprintf(pager, "Checksum: 0x%08x\n",
+               fprintf(pager, "Checksum: 0x%08x",
                        ext2fs_le32_to_cpu(tail->dt_checksum));
+               if (tail->dt_checksum != crc)
+                       fprintf(pager, " --- EXPECTED: 0x%08x", crc);
+               fputc('\n', pager);
        }
 
        for (i=0; i < count; i++) {
@@ -199,6 +202,7 @@ static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
        char            *cbuf;
        errcode_t       errcode;
        blk64_t         pblk;
+       __u32           crc;
 
        cbuf = malloc(fs->blocksize);
        if (!cbuf) {
@@ -216,13 +220,21 @@ static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
        errcode = io_channel_read_blk64(current_fs->io, pblk, 1, buf);
        if (errcode) {
                com_err("htree_dump_int_block", errcode,
-                       "while  reading block %llu\n", blk);
+                       "while reading block %llu\n", blk);
                goto errout;
        }
 
+       errcode = ext2fs_dx_csum(current_fs, ino,
+                                (struct ext2_dir_entry *) buf, &crc, NULL);
+       if (errcode) {
+               com_err("htree_dump_int_block", errcode,
+                       "while calculating checksum for logical block %llu\n",
+                       (unsigned long long) blk);
+               crc = (unsigned int) -1;
+       }
        htree_dump_int_node(fs, ino, inode, rootnode,
                            (struct ext2_dx_entry *) (buf+8),
-                           cbuf, level);
+                           crc, cbuf, level);
 errout:
        free(cbuf);
 }
@@ -239,6 +251,7 @@ void do_htree_dump(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
        struct          ext2_dx_root_info  *rootnode;
        struct          ext2_dx_entry *ent;
        errcode_t       errcode;
+       __u32           crc;
 
        if (check_fs_open(argv[0]))
                return;
@@ -293,7 +306,14 @@ void do_htree_dump(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
        ent = (struct ext2_dx_entry *)
                ((char *)rootnode + rootnode->info_length);
 
-       htree_dump_int_node(current_fs, ino, &inode, rootnode, ent,
+       errcode = ext2fs_dx_csum(current_fs, ino,
+                                (struct ext2_dir_entry *) buf, &crc, NULL);
+       if (errcode) {
+               com_err("htree_dump_int_block", errcode,
+                       "while calculating checksum for htree root\n");
+               crc = (unsigned int) -1;
+       }
+       htree_dump_int_node(current_fs, ino, &inode, rootnode, ent, crc,
                            buf + current_fs->blocksize,
                            rootnode->indirect_levels);
 

diff --git a/lib/ext2fs/csum.c b/lib/ext2fs/csum.c
index bc80939..2c5b0f2 100644 (file)
--- a/lib/ext2fs/csum.c
+++ b/lib/ext2fs/csum.c
@@ -358,9 +358,9 @@ static errcode_t ext2fs_dirent_csum_set(ext2_filsys fs, ext2_ino_t inum,
        return 0;
 }
 
-static errcode_t ext2fs_dx_csum(ext2_filsys fs, ext2_ino_t inum,
-                               struct ext2_dir_entry *dirent,
-                               __u32 *crc, struct ext2_dx_tail **ret_t)
+errcode_t ext2fs_dx_csum(ext2_filsys fs, ext2_ino_t inum,
+                        struct ext2_dir_entry *dirent,
+                        __u32 *crc, struct ext2_dx_tail **ret_t)
 {
        errcode_t retval;
        char *buf = (char *)dirent;

diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index a5ed10f..da30994 100644 (file)
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -1082,6 +1082,9 @@ extern errcode_t ext2fs_get_dx_countlimit(ext2_filsys fs,
                                          struct ext2_dir_entry *dirent,
                                          struct ext2_dx_countlimit **cc,
                                          int *offset);
+extern errcode_t ext2fs_dx_csum(ext2_filsys fs, ext2_ino_t inum,
+                               struct ext2_dir_entry *dirent,
+                               __u32 *crc, struct ext2_dx_tail **ret_t);
 extern errcode_t ext2fs_extent_block_csum_set(ext2_filsys fs,
                                              ext2_ino_t inum,
                                              struct ext3_extent_header *eh);