X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;ds=sidebyside;f=lib%2Fext2fs%2Fcsum.c;h=607f74a7e9c0b518ecc1e346f822ddcb44e6a4c9;hb=1b977a0fad7be60d444228b5802683ff6b78baf2;hp=f02d676c31679dd40d99e988f95f08589fb0d5bb;hpb=d7cca6b06f366f998ed43346f9b6fca9e163692f;p=tools%2Fe2fsprogs.git diff --git a/lib/ext2fs/csum.c b/lib/ext2fs/csum.c index f02d676..607f74a 100644 --- a/lib/ext2fs/csum.c +++ b/lib/ext2fs/csum.c @@ -5,11 +5,12 @@ * Copyright (C) 2006, 2007 by Andreas Dilger * * %Begin-Header% - * This file may be redistributed under the terms of the GNU Public - * License. + * This file may be redistributed under the terms of the GNU Library + * General Public License, version 2. * %End-Header% */ +#include "config.h" #if HAVE_SYS_TYPES_H #include #endif @@ -29,44 +30,761 @@ #define STATIC static #endif -STATIC __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group) +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 = 0; 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); - 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; + struct ext4_group_desc swabdesc; - /* Have to swab back to little-endian to do the checksum */ - ext2fs_swap_group_desc(&swabdesc); - desc = &swabdesc; + /* Have to swab back to little-endian to do the checksum */ + memcpy(&swabdesc, desc, size); + ext2fs_swap_group_desc2(fs, + (struct ext2_group_desc *) &swabdesc); + desc = (struct ext2_group_desc *) &swabdesc; - group = ext2fs_swab32(group); + 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 < fs->super->s_desc_size) { - crc = ext2fs_crc16(crc, (char *)desc + offset, - fs->super->s_desc_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; + + crc = crc32 & 0xFFFF; + goto out; + } + + /* old crc16 code */ + size_t 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); } +out: return crc; } int ext2fs_group_desc_csum_verify(ext2_filsys fs, dgrp_t group) { - if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, - EXT4_FEATURE_RO_COMPAT_GDT_CSUM) && + if (ext2fs_has_group_desc_csum(fs) && (ext2fs_bg_checksum(fs, group) != ext2fs_group_desc_csum(fs, group))) return 0; @@ -76,8 +794,7 @@ int ext2fs_group_desc_csum_verify(ext2_filsys fs, dgrp_t group) void ext2fs_group_desc_csum_set(ext2_filsys fs, dgrp_t group) { - if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super, - EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) + if (!ext2fs_has_group_desc_csum(fs)) return; /* ext2fs_bg_checksum_set() sets the actual checksum field but @@ -111,15 +828,14 @@ errcode_t ext2fs_set_gdt_csum(ext2_filsys fs) if (!fs->inode_map) return EXT2_ET_NO_INODE_BITMAP; - if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super, - EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) + if (!ext2fs_has_group_desc_csum(fs)) return 0; for (i = 0; i < fs->group_desc_count; i++) { - unsigned int old_csum = ext2fs_bg_checksum(fs, i); - int old_unused = ext2fs_bg_itable_unused(fs, i); - unsigned int old_flags = ext2fs_bg_flags(fs, i); - int old_free_inodes_count = ext2fs_bg_free_inodes_count(fs, i); + __u32 old_csum = ext2fs_bg_checksum(fs, i); + __u32 old_unused = ext2fs_bg_itable_unused(fs, i); + __u32 old_flags = ext2fs_bg_flags(fs, i); + __u32 old_free_inodes_count = ext2fs_bg_free_inodes_count(fs, i); if (old_free_inodes_count == sb->s_inodes_per_group) { ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT); @@ -148,19 +864,31 @@ errcode_t ext2fs_set_gdt_csum(ext2_filsys fs) } #ifdef DEBUG +#include "e2p/e2p.h" + 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_group_desc *desc; + size_t size; struct ext2_super_block *sb = fs->super; - + int offset = offsetof(struct ext2_group_desc, bg_checksum); #ifdef WORDS_BIGENDIAN - struct ext2_group_desc swabdesc = fs->group_desc[group]; + struct ext4_group_desc swabdesc; +#endif + desc = ext2fs_group_desc(fs, fs->group_desc, group); + size = fs->super->s_desc_size; + if (size < EXT2_MIN_DESC_SIZE) + size = EXT2_MIN_DESC_SIZE; + if (size > sizeof(struct ext4_group_desc)) + size = sizeof(struct ext4_group_desc); +#ifdef WORDS_BIGENDIAN /* Have to swab back to little-endian to do the checksum */ - ext2fs_swap_group_desc(&swabdesc); - desc = &swabdesc; + memcpy(&swabdesc, desc, size); + ext2fs_swap_group_desc2(fs, (struct ext2_group_desc *) &swabdesc); + desc = (struct ext2_group_desc *) &swabdesc; swabgroup = ext2fs_swab32(group); #else @@ -169,11 +897,15 @@ void print_csum(const char *msg, ext2_filsys fs, dgrp_t group) crc1 = ext2fs_crc16(~0, sb->s_uuid, sizeof(fs->super->s_uuid)); crc2 = ext2fs_crc16(crc1, &swabgroup, sizeof(swabgroup)); - crc3 = ext2fs_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)); + crc3 = ext2fs_crc16(crc2, desc, offset); + offset += sizeof(desc->bg_checksum); /* skip checksum */ + /* for checksum of struct ext4_group_desc do the rest...*/ + if (offset < size) + crc3 = ext2fs_crc16(crc3, (char *)desc + offset, size - offset); + + printf("%s UUID %s=%04x, grp %u=%04x: %04x=%04x\n", + msg, e2p_uuid2str(sb->s_uuid), crc1, group, crc2, crc3, + ext2fs_group_desc_csum(fs, group)); } unsigned char sb_uuid[16] = { 0x4f, 0x25, 0xe8, 0xcf, 0xe7, 0x97, 0x48, 0x23,