X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lib%2Fext2fs%2Fcsum.c;h=9fa3f24f858af666e0f40cfd9c35f21fdbce65dd;hb=c4111cd7eaabee63155ffeb675f806d452e9a191;hp=dca42a0f7a84f485c853569c368688c1fa57af00;hpb=4efbac6fed75c29d3d5f1b676b932754653a2ac5;p=tools%2Fe2fsprogs.git diff --git a/lib/ext2fs/csum.c b/lib/ext2fs/csum.c index dca42a0..9fa3f24 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 @@ -29,22 +30,33 @@ #define STATIC static #endif -STATIC __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group) +__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)) { + printf("%s: illegal s_desc_size(%zd)\n", __func__, size); + size = sizeof(struct ext4_group_desc); + } - desc = &fs->group_desc[group]; + 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); + size_t 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; + memcpy(&swabdesc, desc, size); + ext2fs_swap_group_desc2(fs, + (struct ext2_group_desc *) &swabdesc); + desc = (struct ext2_group_desc *) &swabdesc; group = ext2fs_swab32(group); #endif @@ -53,11 +65,10 @@ STATIC __u16 ext2fs_group_desc_csum(ext2_filsys fs, dgrp_t group) crc = ext2fs_crc16(crc, &group, sizeof(group)); crc = ext2fs_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) { + if (offset < size) { crc = ext2fs_crc16(crc, (char *)desc + offset, - fs->super->s_desc_size - offset); + size - offset); } } @@ -68,7 +79,7 @@ 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) && - (fs->group_desc[group].bg_checksum != + (ext2fs_bg_checksum(fs, group) != ext2fs_group_desc_csum(fs, group))) return 0; @@ -77,10 +88,13 @@ 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)) - fs->group_desc[group].bg_checksum = - ext2fs_group_desc_csum(fs, group); + if (!EXT2_HAS_RO_COMPAT_FEATURE(fs->super, + EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) + return; + + /* ext2fs_bg_checksum_set() sets the actual checksum field but + * does not calculate the checksum itself. */ + ext2fs_bg_checksum_set(fs, group, ext2fs_group_desc_csum(fs, group)); } static __u32 find_last_inode_ingrp(ext2fs_inode_bitmap bitmap, @@ -103,7 +117,6 @@ static __u32 find_last_inode_ingrp(ext2fs_inode_bitmap bitmap, errcode_t ext2fs_set_gdt_csum(ext2_filsys fs) { struct ext2_super_block *sb = fs->super; - struct ext2_group_desc *bg = fs->group_desc; int dirty = 0; dgrp_t i; @@ -114,27 +127,31 @@ errcode_t ext2fs_set_gdt_csum(ext2_filsys fs) EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) return 0; - for (i = 0; i < fs->group_desc_count; i++, bg++) { - int old_csum = bg->bg_checksum; - int old_unused = bg->bg_itable_unused; - int old_flags = bg->bg_flags; + for (i = 0; i < fs->group_desc_count; 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 (bg->bg_free_inodes_count == sb->s_inodes_per_group) { - bg->bg_flags |= EXT2_BG_INODE_UNINIT; - bg->bg_itable_unused = sb->s_inodes_per_group; + if (old_free_inodes_count == sb->s_inodes_per_group) { + ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT); + ext2fs_bg_itable_unused_set(fs, i, sb->s_inodes_per_group); } else { - bg->bg_flags &= ~EXT2_BG_INODE_UNINIT; - bg->bg_itable_unused = sb->s_inodes_per_group - + int unused = + sb->s_inodes_per_group - find_last_inode_ingrp(fs->inode_map, - sb->s_inodes_per_group,i); + sb->s_inodes_per_group, i); + + ext2fs_bg_flags_clear(fs, i, EXT2_BG_INODE_UNINIT); + ext2fs_bg_itable_unused_set(fs, i, unused); } ext2fs_group_desc_csum_set(fs, i); - if (old_flags != bg->bg_flags) + if (old_flags != ext2fs_bg_flags(fs, i)) dirty = 1; - if (old_unused != bg->bg_itable_unused) + if (old_unused != ext2fs_bg_itable_unused(fs, i)) dirty = 1; - if (old_csum != bg->bg_checksum) + if (old_csum != ext2fs_bg_checksum(fs, i)) dirty = 1; } if (dirty) @@ -143,19 +160,30 @@ 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 = ext2fs_group_desc(fs, fs->group_desc, group); + 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 + 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 @@ -164,11 +192,15 @@ 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, @@ -196,13 +228,13 @@ int main(int argc, char **argv) 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; + ext2fs_block_bitmap_loc_set(fs, i, 124); + ext2fs_inode_bitmap_loc_set(fs, i, 125); + ext2fs_inode_table_loc_set(fs, i, 126); + ext2fs_bg_free_blocks_count_set(fs, i, 31119); + ext2fs_bg_free_inodes_count_set(fs, i, 15701); + ext2fs_bg_used_dirs_count_set(fs, i, 2); + ext2fs_bg_flags_zap(fs, i); }; csum1 = ext2fs_group_desc_csum(fs, 0); @@ -224,7 +256,7 @@ int main(int argc, char **argv) printf("checksums for different groups shouldn't match\n"); exit(1); } - fs->group_desc[0].bg_checksum = csum1; + ext2fs_bg_checksum_set(fs, 0, csum1); csum2 = ext2fs_group_desc_csum(fs, 0); print_csum("csum_set", fs, 0); if (csum1 != csum2) { @@ -241,9 +273,10 @@ int main(int argc, char **argv) printf("checksums for different filesystems shouldn't match\n"); exit(1); } - csum1 = fs->group_desc[0].bg_checksum = ext2fs_group_desc_csum(fs, 0); + csum1 = ext2fs_group_desc_csum(fs, 0); + ext2fs_bg_checksum_set(fs, 0, csum1); print_csum("csum_new", fs, 0); - fs->group_desc[0].bg_free_blocks_count = 1; + ext2fs_bg_free_blocks_count_set(fs, 0, 1); csum2 = ext2fs_group_desc_csum(fs, 0); print_csum("csum_blk", fs, 0); if (csum1 == csum2) {