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libext2fs: use strcpy()/strcat() instead of sprintf() in bmap functions
[tools/e2fsprogs.git] / lib / ext2fs / csum.c
index dca42a0..9fa3f24 100644 (file)
@@ -5,11 +5,12 @@
  * Copyright (C) 2006, 2007 by Andreas Dilger <adilger@clusterfs.com>
  *
  * %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 <sys/types.h>
 #endif
 #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) {