#define STATIC static
#endif
+static __u32 ext2fs_mmp_csum(ext2_filsys fs, struct mmp_struct *mmp)
+{
+ int offset = offsetof(struct mmp_struct, mmp_checksum);
+
+ return ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)mmp, offset);
+}
+
+int ext2fs_mmp_csum_verify(ext2_filsys fs, struct mmp_struct *mmp)
+{
+ __u32 calculated;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+
+ calculated = ext2fs_mmp_csum(fs, mmp);
+
+ return ext2fs_le32_to_cpu(mmp->mmp_checksum) == calculated;
+}
+
+errcode_t ext2fs_mmp_csum_set(ext2_filsys fs, struct mmp_struct *mmp)
+{
+ __u32 crc;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ crc = ext2fs_mmp_csum(fs, mmp);
+ mmp->mmp_checksum = ext2fs_cpu_to_le32(crc);
+
+ return 0;
+}
+
+int ext2fs_verify_csum_type(ext2_filsys fs, struct ext2_super_block *sb)
+{
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+
+ return sb->s_checksum_type == EXT2_CRC32C_CHKSUM;
+}
+
+static __u32 ext2fs_superblock_csum(ext2_filsys fs EXT2FS_ATTR((unused)),
+ struct ext2_super_block *sb)
+{
+ int offset = offsetof(struct ext2_super_block, s_checksum);
+
+ return ext2fs_crc32c_le(~0, (unsigned char *)sb, offset);
+}
+
+int ext2fs_superblock_csum_verify(ext2_filsys fs, struct ext2_super_block *sb)
+{
+ __u32 calculated;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+
+ calculated = ext2fs_superblock_csum(fs, sb);
+
+ return ext2fs_le32_to_cpu(sb->s_checksum) == calculated;
+}
+
+errcode_t ext2fs_superblock_csum_set(ext2_filsys fs,
+ struct ext2_super_block *sb)
+{
+ __u32 crc;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ crc = ext2fs_superblock_csum(fs, sb);
+ sb->s_checksum = ext2fs_cpu_to_le32(crc);
+
+ return 0;
+}
+
+static errcode_t ext2fs_ext_attr_block_csum(ext2_filsys fs,
+ ext2_ino_t inum EXT2FS_ATTR((unused)),
+ blk64_t block,
+ struct ext2_ext_attr_header *hdr,
+ __u32 *crc)
+{
+ char *buf = (char *)hdr;
+ __u32 old_crc = hdr->h_checksum;
+
+ hdr->h_checksum = 0;
+ block = ext2fs_cpu_to_le64(block);
+ *crc = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)&block,
+ sizeof(block));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)buf, fs->blocksize);
+ hdr->h_checksum = old_crc;
+
+ return 0;
+}
+
+int ext2fs_ext_attr_block_csum_verify(ext2_filsys fs, ext2_ino_t inum,
+ blk64_t block,
+ struct ext2_ext_attr_header *hdr)
+{
+ __u32 calculated;
+ errcode_t retval;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+
+ retval = ext2fs_ext_attr_block_csum(fs, inum, block, hdr, &calculated);
+ if (retval)
+ return 0;
+
+ return ext2fs_le32_to_cpu(hdr->h_checksum) == calculated;
+}
+
+errcode_t ext2fs_ext_attr_block_csum_set(ext2_filsys fs, ext2_ino_t inum,
+ blk64_t block,
+ struct ext2_ext_attr_header *hdr)
+{
+ errcode_t retval;
+ __u32 crc;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ retval = ext2fs_ext_attr_block_csum(fs, inum, block, hdr, &crc);
+ if (retval)
+ return retval;
+ hdr->h_checksum = ext2fs_cpu_to_le32(crc);
+ return 0;
+}
+
+static __u16 do_nothing16(__u16 x)
+{
+ return x;
+}
+
+static __u16 disk_to_host16(__u16 x)
+{
+ return ext2fs_le16_to_cpu(x);
+}
+
+static errcode_t __get_dx_countlimit(ext2_filsys fs,
+ struct ext2_dir_entry *dirent,
+ struct ext2_dx_countlimit **cc,
+ int *offset,
+ int need_swab)
+{
+ struct ext2_dir_entry *dp;
+ struct ext2_dx_root_info *root;
+ struct ext2_dx_countlimit *c;
+ int count_offset, max_sane_entries;
+ unsigned int rec_len;
+ __u16 (*translate)(__u16) = (need_swab ? disk_to_host16 : do_nothing16);
+
+ rec_len = translate(dirent->rec_len);
+
+ if (rec_len == fs->blocksize && translate(dirent->name_len) == 0)
+ count_offset = 8;
+ else if (rec_len == 12) {
+ dp = (struct ext2_dir_entry *)(((char *)dirent) + rec_len);
+ rec_len = translate(dp->rec_len);
+ if (rec_len != fs->blocksize - 12)
+ return EXT2_ET_DB_NOT_FOUND;
+ root = (struct ext2_dx_root_info *)(((char *)dp + 12));
+ if (root->reserved_zero ||
+ root->info_length != sizeof(struct ext2_dx_root_info))
+ return EXT2_ET_DB_NOT_FOUND;
+ count_offset = 32;
+ } else
+ return EXT2_ET_DB_NOT_FOUND;
+
+ c = (struct ext2_dx_countlimit *)(((char *)dirent) + count_offset);
+ max_sane_entries = (fs->blocksize - count_offset) /
+ sizeof(struct ext2_dx_entry);
+ if (ext2fs_le16_to_cpu(c->limit) > max_sane_entries ||
+ ext2fs_le16_to_cpu(c->count) > max_sane_entries)
+ return EXT2_ET_DIR_NO_SPACE_FOR_CSUM;
+
+ if (offset)
+ *offset = count_offset;
+ if (cc)
+ *cc = c;
+
+ return 0;
+}
+
+errcode_t ext2fs_get_dx_countlimit(ext2_filsys fs,
+ struct ext2_dir_entry *dirent,
+ struct ext2_dx_countlimit **cc,
+ int *offset)
+{
+ return __get_dx_countlimit(fs, dirent, cc, offset, 0);
+}
+
+void ext2fs_initialize_dirent_tail(ext2_filsys fs,
+ struct ext2_dir_entry_tail *t)
+{
+ memset(t, 0, sizeof(struct ext2_dir_entry_tail));
+ ext2fs_set_rec_len(fs, sizeof(struct ext2_dir_entry_tail),
+ (struct ext2_dir_entry *)t);
+ t->det_reserved_name_len = EXT2_DIR_NAME_LEN_CSUM;
+}
+
+static errcode_t __get_dirent_tail(ext2_filsys fs,
+ struct ext2_dir_entry *dirent,
+ struct ext2_dir_entry_tail **tt,
+ int need_swab)
+{
+ struct ext2_dir_entry *d;
+ void *top;
+ struct ext2_dir_entry_tail *t;
+ unsigned int rec_len;
+ errcode_t retval = 0;
+ __u16 (*translate)(__u16) = (need_swab ? disk_to_host16 : do_nothing16);
+
+ d = dirent;
+ top = EXT2_DIRENT_TAIL(dirent, fs->blocksize);
+
+ rec_len = translate(d->rec_len);
+ while (rec_len && !(rec_len & 0x3)) {
+ d = (struct ext2_dir_entry *)(((char *)d) + rec_len);
+ if ((void *)d >= top)
+ break;
+ rec_len = translate(d->rec_len);
+ }
+
+ if (d != top)
+ return EXT2_ET_DIR_NO_SPACE_FOR_CSUM;
+
+ t = (struct ext2_dir_entry_tail *)d;
+ if (t->det_reserved_zero1 ||
+ translate(t->det_rec_len) != sizeof(struct ext2_dir_entry_tail) ||
+ translate(t->det_reserved_name_len) != EXT2_DIR_NAME_LEN_CSUM)
+ return EXT2_ET_DIR_NO_SPACE_FOR_CSUM;
+
+ if (tt)
+ *tt = t;
+ return retval;
+}
+
+int ext2fs_dirent_has_tail(ext2_filsys fs, struct ext2_dir_entry *dirent)
+{
+ return __get_dirent_tail(fs, dirent, NULL, 0) == 0;
+}
+
+static errcode_t ext2fs_dirent_csum(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_dir_entry *dirent, __u32 *crc,
+ int size)
+{
+ errcode_t retval;
+ char *buf = (char *)dirent;
+ __u32 gen;
+ struct ext2_inode inode;
+
+ retval = ext2fs_read_inode(fs, inum, &inode);
+ if (retval)
+ return retval;
+
+ inum = ext2fs_cpu_to_le32(inum);
+ gen = ext2fs_cpu_to_le32(inode.i_generation);
+ *crc = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)&inum,
+ sizeof(inum));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)&gen, sizeof(gen));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)buf, size);
+
+ return 0;
+}
+
+int ext2fs_dirent_csum_verify(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_dir_entry *dirent)
+{
+ errcode_t retval;
+ __u32 calculated;
+ struct ext2_dir_entry_tail *t;
+
+ retval = __get_dirent_tail(fs, dirent, &t, 1);
+ if (retval)
+ return 1;
+
+ /*
+ * The checksum field is overlaid with the dirent->name field
+ * so the swapfs.c functions won't change the endianness.
+ */
+ retval = ext2fs_dirent_csum(fs, inum, dirent, &calculated,
+ (char *)t - (char *)dirent);
+ if (retval)
+ return 0;
+ return ext2fs_le32_to_cpu(t->det_checksum) == calculated;
+}
+
+static errcode_t ext2fs_dirent_csum_set(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_dir_entry *dirent)
+{
+ errcode_t retval;
+ __u32 crc;
+ struct ext2_dir_entry_tail *t;
+
+ retval = __get_dirent_tail(fs, dirent, &t, 1);
+ if (retval)
+ return retval;
+
+ /* swapfs.c functions don't change the checksum endianness */
+ retval = ext2fs_dirent_csum(fs, inum, dirent, &crc,
+ (char *)t - (char *)dirent);
+ if (retval)
+ return retval;
+ t->det_checksum = ext2fs_cpu_to_le32(crc);
+ return 0;
+}
+
+static errcode_t ext2fs_dx_csum(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_dir_entry *dirent,
+ __u32 *crc, int count_offset, int count,
+ struct ext2_dx_tail *t)
+{
+ errcode_t retval;
+ char *buf = (char *)dirent;
+ int size;
+ __u32 old_csum, gen;
+ struct ext2_inode inode;
+
+ size = count_offset + (count * sizeof(struct ext2_dx_entry));
+ old_csum = t->dt_checksum;
+ t->dt_checksum = 0;
+
+ retval = ext2fs_read_inode(fs, inum, &inode);
+ if (retval)
+ return retval;
+
+ inum = ext2fs_cpu_to_le32(inum);
+ gen = ext2fs_cpu_to_le32(inode.i_generation);
+ *crc = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)&inum,
+ sizeof(inum));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)&gen, sizeof(gen));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)buf, size);
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)t,
+ sizeof(struct ext2_dx_tail));
+ t->dt_checksum = old_csum;
+
+ return 0;
+}
+
+static int ext2fs_dx_csum_verify(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_dir_entry *dirent)
+{
+ __u32 calculated;
+ errcode_t retval;
+ struct ext2_dx_countlimit *c;
+ struct ext2_dx_tail *t;
+ int count_offset, limit, count;
+
+ retval = __get_dx_countlimit(fs, dirent, &c, &count_offset, 1);
+ if (retval)
+ return 1;
+ limit = ext2fs_le16_to_cpu(c->limit);
+ count = ext2fs_le16_to_cpu(c->count);
+ if (count_offset + (limit * sizeof(struct ext2_dx_entry)) >
+ fs->blocksize - sizeof(struct ext2_dx_tail))
+ return 0;
+ /* htree structs are accessed in LE order */
+ t = (struct ext2_dx_tail *)(((struct ext2_dx_entry *)c) + limit);
+ retval = ext2fs_dx_csum(fs, inum, dirent, &calculated, count_offset,
+ count, t);
+ if (retval)
+ return 0;
+
+ return ext2fs_le32_to_cpu(t->dt_checksum) == calculated;
+}
+
+static errcode_t ext2fs_dx_csum_set(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_dir_entry *dirent)
+{
+ __u32 crc;
+ errcode_t retval = 0;
+ struct ext2_dx_countlimit *c;
+ struct ext2_dx_tail *t;
+ int count_offset, limit, count;
+
+ retval = __get_dx_countlimit(fs, dirent, &c, &count_offset, 1);
+ if (retval)
+ return retval;
+ limit = ext2fs_le16_to_cpu(c->limit);
+ count = ext2fs_le16_to_cpu(c->count);
+ if (count_offset + (limit * sizeof(struct ext2_dx_entry)) >
+ fs->blocksize - sizeof(struct ext2_dx_tail))
+ return EXT2_ET_DIR_NO_SPACE_FOR_CSUM;
+ t = (struct ext2_dx_tail *)(((struct ext2_dx_entry *)c) + limit);
+
+ /* htree structs are accessed in LE order */
+ retval = ext2fs_dx_csum(fs, inum, dirent, &crc, count_offset, count, t);
+ if (retval)
+ return retval;
+ t->dt_checksum = ext2fs_cpu_to_le32(crc);
+ return retval;
+}
+
+int ext2fs_dir_block_csum_verify(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_dir_entry *dirent)
+{
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+
+ if (__get_dirent_tail(fs, dirent, NULL, 1) == 0)
+ return ext2fs_dirent_csum_verify(fs, inum, dirent);
+ if (__get_dx_countlimit(fs, dirent, NULL, NULL, 1) == 0)
+ return ext2fs_dx_csum_verify(fs, inum, dirent);
+
+ return 0;
+}
+
+errcode_t ext2fs_dir_block_csum_set(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_dir_entry *dirent)
+{
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ if (__get_dirent_tail(fs, dirent, NULL, 1) == 0)
+ return ext2fs_dirent_csum_set(fs, inum, dirent);
+ if (__get_dx_countlimit(fs, dirent, NULL, NULL, 1) == 0)
+ return ext2fs_dx_csum_set(fs, inum, dirent);
+
+ if (fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS)
+ return 0;
+ return EXT2_ET_DIR_NO_SPACE_FOR_CSUM;
+}
+
+#define EXT3_EXTENT_TAIL_OFFSET(hdr) (sizeof(struct ext3_extent_header) + \
+ (sizeof(struct ext3_extent) * ext2fs_le16_to_cpu((hdr)->eh_max)))
+
+static struct ext3_extent_tail *get_extent_tail(struct ext3_extent_header *h)
+{
+ return (struct ext3_extent_tail *)(((char *)h) +
+ EXT3_EXTENT_TAIL_OFFSET(h));
+}
+
+static errcode_t ext2fs_extent_block_csum(ext2_filsys fs, ext2_ino_t inum,
+ struct ext3_extent_header *eh,
+ __u32 *crc)
+{
+ int size;
+ __u32 gen;
+ errcode_t retval;
+ struct ext2_inode inode;
+
+ size = EXT3_EXTENT_TAIL_OFFSET(eh) + offsetof(struct ext3_extent_tail,
+ et_checksum);
+
+ retval = ext2fs_read_inode(fs, inum, &inode);
+ if (retval)
+ return retval;
+ inum = ext2fs_cpu_to_le32(inum);
+ gen = ext2fs_cpu_to_le32(inode.i_generation);
+ *crc = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)&inum,
+ sizeof(inum));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)&gen, sizeof(gen));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)eh, size);
+
+ return 0;
+}
+
+int ext2fs_extent_block_csum_verify(ext2_filsys fs, ext2_ino_t inum,
+ struct ext3_extent_header *eh)
+{
+ errcode_t retval;
+ __u32 provided, calculated;
+ struct ext3_extent_tail *t = get_extent_tail(eh);
+
+ /*
+ * The extent tree structures are accessed in LE order, so we must
+ * swap the checksum bytes here.
+ */
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+
+ provided = ext2fs_le32_to_cpu(t->et_checksum);
+ retval = ext2fs_extent_block_csum(fs, inum, eh, &calculated);
+ if (retval)
+ return 0;
+
+ return provided == calculated;
+}
+
+errcode_t ext2fs_extent_block_csum_set(ext2_filsys fs, ext2_ino_t inum,
+ struct ext3_extent_header *eh)
+{
+ errcode_t retval;
+ __u32 crc;
+ struct ext3_extent_tail *t = get_extent_tail(eh);
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ /*
+ * The extent tree structures are accessed in LE order, so we must
+ * swap the checksum bytes here.
+ */
+ retval = ext2fs_extent_block_csum(fs, inum, eh, &crc);
+ if (retval)
+ return retval;
+ t->et_checksum = ext2fs_cpu_to_le32(crc);
+ return retval;
+}
+
+int ext2fs_inode_bitmap_csum_verify(ext2_filsys fs, dgrp_t group,
+ char *bitmap, int size)
+{
+ struct ext4_group_desc *gdp = (struct ext4_group_desc *)
+ ext2fs_group_desc(fs, fs->group_desc, group);
+ __u32 provided, calculated;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+ provided = gdp->bg_inode_bitmap_csum_lo;
+ calculated = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)bitmap,
+ size);
+ if (fs->super->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END)
+ provided |= (__u32)gdp->bg_inode_bitmap_csum_hi << 16;
+ else
+ calculated &= 0xFFFF;
+
+ return provided == calculated;
+}
+
+errcode_t ext2fs_inode_bitmap_csum_set(ext2_filsys fs, dgrp_t group,
+ char *bitmap, int size)
+{
+ __u32 crc;
+ struct ext4_group_desc *gdp = (struct ext4_group_desc *)
+ ext2fs_group_desc(fs, fs->group_desc, group);
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ crc = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)bitmap, size);
+ gdp->bg_inode_bitmap_csum_lo = crc & 0xFFFF;
+ if (fs->super->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END)
+ gdp->bg_inode_bitmap_csum_hi = crc >> 16;
+
+ return 0;
+}
+
+int ext2fs_block_bitmap_csum_verify(ext2_filsys fs, dgrp_t group,
+ char *bitmap, int size)
+{
+ struct ext4_group_desc *gdp = (struct ext4_group_desc *)
+ ext2fs_group_desc(fs, fs->group_desc, group);
+ __u32 provided, calculated;
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+ provided = gdp->bg_block_bitmap_csum_lo;
+ calculated = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)bitmap,
+ size);
+ if (fs->super->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_LOCATION)
+ provided |= (__u32)gdp->bg_block_bitmap_csum_hi << 16;
+ else
+ calculated &= 0xFFFF;
+
+ return provided == calculated;
+}
+
+errcode_t ext2fs_block_bitmap_csum_set(ext2_filsys fs, dgrp_t group,
+ char *bitmap, int size)
+{
+ __u32 crc;
+ struct ext4_group_desc *gdp = (struct ext4_group_desc *)
+ ext2fs_group_desc(fs, fs->group_desc, group);
+
+ if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ crc = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)bitmap, size);
+ gdp->bg_block_bitmap_csum_lo = crc & 0xFFFF;
+ if (fs->super->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_LOCATION)
+ gdp->bg_block_bitmap_csum_hi = crc >> 16;
+
+ return 0;
+}
+
+static errcode_t ext2fs_inode_csum(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_inode_large *inode,
+ __u32 *crc, int has_hi)
+{
+ __u32 gen;
+ struct ext2_inode_large *desc = inode;
+ size_t size = fs->super->s_inode_size;
+ __u16 old_lo;
+ __u16 old_hi = 0;
+
+ old_lo = inode->i_checksum_lo;
+ inode->i_checksum_lo = 0;
+ if (has_hi) {
+ old_hi = inode->i_checksum_hi;
+ inode->i_checksum_hi = 0;
+ }
+
+ inum = ext2fs_cpu_to_le32(inum);
+ gen = inode->i_generation;
+ *crc = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)&inum,
+ sizeof(inum));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)&gen, sizeof(gen));
+ *crc = ext2fs_crc32c_le(*crc, (unsigned char *)desc, size);
+
+ inode->i_checksum_lo = old_lo;
+ if (has_hi)
+ inode->i_checksum_hi = old_hi;
+ return 0;
+}
+
+int ext2fs_inode_csum_verify(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_inode_large *inode)
+{
+ errcode_t retval;
+ __u32 provided, calculated;
+ unsigned int i, has_hi;
+ char *cp;
+
+ if (fs->super->s_creator_os != EXT2_OS_LINUX ||
+ !EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 1;
+
+ has_hi = (EXT2_INODE_SIZE(fs->super) > EXT2_GOOD_OLD_INODE_SIZE &&
+ inode->i_extra_isize >= EXT4_INODE_CSUM_HI_EXTRA_END);
+
+ provided = ext2fs_le16_to_cpu(inode->i_checksum_lo);
+ retval = ext2fs_inode_csum(fs, inum, inode, &calculated, has_hi);
+ if (retval)
+ return 0;
+ if (has_hi) {
+ __u32 hi = ext2fs_le16_to_cpu(inode->i_checksum_hi);
+ provided |= hi << 16;
+ } else
+ calculated &= 0xFFFF;
+
+ if (provided == calculated)
+ return 1;
+
+ /*
+ * If the checksum didn't match, it's possible it was due to
+ * the inode being all zero's. It's unlikely this is the
+ * case, but it can happen. So check for it here. (We only
+ * check the base inode since that's good enough, and it's not
+ * worth the bother to figure out how much of the extended
+ * inode, if any, is present.)
+ */
+ for (cp = (char *) inode, i = 0;
+ i < sizeof(struct ext2_inode);
+ cp++, i++)
+ if (*cp)
+ return 0;
+ return 1; /* Inode must have been all zero's */
+}
+
+errcode_t ext2fs_inode_csum_set(ext2_filsys fs, ext2_ino_t inum,
+ struct ext2_inode_large *inode)
+{
+ errcode_t retval;
+ __u32 crc;
+ int has_hi;
+
+ if (fs->super->s_creator_os != EXT2_OS_LINUX ||
+ !EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ return 0;
+
+ has_hi = (EXT2_INODE_SIZE(fs->super) > EXT2_GOOD_OLD_INODE_SIZE &&
+ inode->i_extra_isize >= EXT4_INODE_CSUM_HI_EXTRA_END);
+
+ retval = ext2fs_inode_csum(fs, inum, inode, &crc, has_hi);
+ if (retval)
+ return retval;
+ inode->i_checksum_lo = ext2fs_cpu_to_le16(crc & 0xFFFF);
+ if (has_hi)
+ inode->i_checksum_hi = ext2fs_cpu_to_le16(crc >> 16);
+ return 0;
+}
+
__u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group)
{
- __u16 crc;
-
- if (fs->super->s_feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
- size_t offset = offsetof(struct ext2_group_desc, bg_checksum);
-
+ struct ext2_group_desc *desc = ext2fs_group_desc(fs, fs->group_desc,
+ group);
+ size_t size = EXT2_DESC_SIZE(fs->super);
+ size_t offset;
- struct ext2_group_desc *desc;
- size_t size;
-
- size = fs->super->s_desc_size;
- if (size < EXT2_MIN_DESC_SIZE)
- size = EXT2_MIN_DESC_SIZE;
- if (size > sizeof(struct ext4_group_desc)) {
- /* This should never happen, but cap it for safety's sake */
- size = sizeof(struct ext4_group_desc);
- }
-
- desc = ext2fs_group_desc(fs, fs->group_desc, group);
-
+ __u16 crc = 0;
#ifdef WORDS_BIGENDIAN
- struct ext4_group_desc swabdesc;
- size_t save_size = size;
- const size_t ext4_bg_size = sizeof(struct ext4_group_desc);
- struct ext2_group_desc *save_desc = desc;
-
- /* Have to swab back to little-endian to do the checksum */
- if (size > ext4_bg_size)
- size = ext4_bg_size;
- memcpy(&swabdesc, desc, size);
- ext2fs_swap_group_desc2(fs,
- (struct ext2_group_desc *) &swabdesc);
- desc = (struct ext2_group_desc *) &swabdesc;
-
- group = ext2fs_swab32(group);
+ struct ext4_group_desc swabdesc;
++ size_t save_size = size;
++ const size_t ext4_bg_size = sizeof(struct ext4_group_desc);
++ struct ext2_group_desc *save_desc = desc;
+
+ /* Have to swab back to little-endian to do the checksum */
++ if (size > ext4_bg_size)
++ size = ext4_bg_size;
+ memcpy(&swabdesc, desc, size);
- ext2fs_swap_group_desc2(fs,
- (struct ext2_group_desc *) &swabdesc);
++ ext2fs_swap_group_desc2(fs, (struct ext2_group_desc *) &swabdesc);
+ desc = (struct ext2_group_desc *) &swabdesc;
-
+ group = ext2fs_swab32(group);
#endif
- crc = ext2fs_crc16(~0, fs->super->s_uuid,
- sizeof(fs->super->s_uuid));
- crc = ext2fs_crc16(crc, &group, sizeof(group));
- crc = ext2fs_crc16(crc, desc, offset);
- offset += sizeof(desc->bg_checksum); /* skip checksum */
- /* for checksum of struct ext4_group_desc do the rest...*/
- if (offset < size) {
- crc = ext2fs_crc16(crc, (char *)desc + offset,
- size - offset);
- }
+
+ if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
+ /* new metadata csum code */
+ __u16 old_crc;
+ __u32 crc32;
+
+ old_crc = desc->bg_checksum;
+ desc->bg_checksum = 0;
+ crc32 = ext2fs_crc32c_le(fs->csum_seed, (unsigned char *)&group,
+ sizeof(group));
+ crc32 = ext2fs_crc32c_le(crc32, (unsigned char *)desc,
+ size);
+ desc->bg_checksum = old_crc;
-
+ #ifdef WORDS_BIGENDIAN
- /*
- * If the size of the bg descriptor is greater than 64
- * bytes, which is the size of the traditional ext4 bg
- * descriptor, checksum the rest of the descriptor here
- */
+ if (save_size > ext4_bg_size)
- crc = ext2fs_crc16(crc,
++ crc32 = ext2fs_crc32c_le(crc32,
+ (char *)save_desc + ext4_bg_size,
+ save_size - ext4_bg_size);
+ #endif
+ crc = crc32 & 0xFFFF;
+ goto out;
}
- size_t offset = offsetof(struct ext2_group_desc, bg_checksum);
+ /* old crc16 code */
++ offset = offsetof(struct ext2_group_desc, bg_checksum);
+ crc = ext2fs_crc16(~0, fs->super->s_uuid,
+ sizeof(fs->super->s_uuid));
+ crc = ext2fs_crc16(crc, &group, sizeof(group));
+ crc = ext2fs_crc16(crc, desc, offset);
+ offset += sizeof(desc->bg_checksum); /* skip checksum */
+ /* for checksum of struct ext4_group_desc do the rest...*/
+ if (offset < size) {
+ crc = ext2fs_crc16(crc, (char *)desc + offset,
+ size - offset);
+ }
++#ifdef WORDS_BIGENDIAN
++ /*
++ * If the size of the bg descriptor is greater than 64
++ * bytes, which is the size of the traditional ext4 bg
++ * descriptor, checksum the rest of the descriptor here
++ */
++ if (save_size > ext4_bg_size)
++ crc = ext2fs_crc16(crc, (char *)save_desc + ext4_bg_size,
++ save_size - ext4_bg_size);
++#endif
+
+out:
return crc;
}
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