Teach ext2fs_open2() to honor the EXT2_FLAG_SUPER_ONLY flag

[tools/e2fsprogs.git] / lib / ext2fs / openfs.c

diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c
index 0362b28..ec2d6cb 100644 (file)
--- a/lib/ext2fs/openfs.c
+++ b/lib/ext2fs/openfs.c
@@ -29,7 +29,6 @@
 
 #include "ext2_fs.h"
 
-
 #include "ext2fs.h"
 #include "e2image.h"
 
@@ -94,6 +93,12 @@ errcode_t ext2fs_open(const char *name, int flags, int superblock,
                            manager, ret_fs);
 }
 
+static void block_sha_map_free_entry(void *data)
+{
+       free(data);
+       return;
+}
+
 /*
  *  Note: if superblock is non-zero, block-size must also be non-zero.
  *     Superblock and block_size can be zero to use the default size.
@@ -121,11 +126,14 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
        blk64_t         group_block, blk;
        char            *dest, *cp;
        int             group_zero_adjust = 0;
+       unsigned int    inode_size;
+       __u64           groups_cnt;
 #ifdef WORDS_BIGENDIAN
        unsigned int    groups_per_block;
        struct ext2_group_desc *gdp;
        int             j;
 #endif
+       char            *time_env;
 
        EXT2_CHECK_MAGIC(manager, EXT2_ET_MAGIC_IO_MANAGER);
 
@@ -139,6 +147,11 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
        /* don't overwrite sb backups unless flag is explicitly cleared */
        fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
        fs->umask = 022;
+
+       time_env = getenv("E2FSPROGS_FAKE_TIME");
+       if (time_env)
+               fs->now = strtoul(time_env, NULL, 0);
+
        retval = ext2fs_get_mem(strlen(name)+1, &fs->device_name);
        if (retval)
                goto cleanup;
@@ -177,10 +190,10 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
                                             fs->image_header);
                if (retval)
                        goto cleanup;
-               if (fs->image_header->magic_number != EXT2_ET_MAGIC_E2IMAGE)
+               if (ext2fs_le32_to_cpu(fs->image_header->magic_number) != EXT2_ET_MAGIC_E2IMAGE)
                        return EXT2_ET_MAGIC_E2IMAGE;
                superblock = 1;
-               block_size = fs->image_header->fs_blocksize;
+               block_size = ext2fs_le32_to_cpu(fs->image_header->fs_blocksize);
        }
 
        /*
@@ -297,7 +310,10 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
                goto cleanup;
        }
        fs->fragsize = fs->blocksize = EXT2_BLOCK_SIZE(fs->super);
-       if (EXT2_INODE_SIZE(fs->super) < EXT2_GOOD_OLD_INODE_SIZE) {
+       inode_size = EXT2_INODE_SIZE(fs->super);
+       if ((inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
+           (inode_size > fs->blocksize) ||
+           (inode_size & (inode_size - 1))) {
                retval = EXT2_ET_CORRUPT_SUPERBLOCK;
                goto cleanup;
        }
@@ -308,12 +324,6 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
                        retval = EXT2_ET_BAD_DESC_SIZE;
                        goto cleanup;
                }
-       } else {
-               if (fs->super->s_desc_size &&
-                   fs->super->s_desc_size != EXT2_MIN_DESC_SIZE) {
-                       retval = EXT2_ET_BAD_DESC_SIZE;
-                       goto cleanup;
-               }
        }
 
        fs->cluster_ratio_bits = fs->super->s_log_cluster_size -
@@ -367,16 +377,24 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
                retval = EXT2_ET_CORRUPT_SUPERBLOCK;
                goto cleanup;
        }
-       fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
-                                                fs->super->s_first_data_block,
-                                                blocks_per_group);
-       if (fs->group_desc_count * EXT2_INODES_PER_GROUP(fs->super) !=
+       groups_cnt = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
+                                      fs->super->s_first_data_block,
+                                      blocks_per_group);
+       if (groups_cnt >> 32) {
+               retval = EXT2_ET_CORRUPT_SUPERBLOCK;
+               goto cleanup;
+       }
+       fs->group_desc_count =  groups_cnt;
+       if (!(flags & EXT2_FLAG_IGNORE_SB_ERRORS) &&
+           (__u64)fs->group_desc_count * EXT2_INODES_PER_GROUP(fs->super) !=
            fs->super->s_inodes_count) {
                retval = EXT2_ET_CORRUPT_SUPERBLOCK;
                goto cleanup;
        }
        fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
                                          EXT2_DESC_PER_BLOCK(fs->super));
+       if (flags & EXT2_FLAG_SUPER_ONLY)
+               goto skip_read_bg;
        retval = ext2fs_get_array(fs->desc_blocks, fs->blocksize,
                                &fs->group_desc);
        if (retval)
@@ -400,7 +418,8 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
 #ifdef WORDS_BIGENDIAN
        groups_per_block = EXT2_DESC_PER_BLOCK(fs->super);
 #endif
-       if (ext2fs_has_feature_meta_bg(fs->super)) {
+       if (ext2fs_has_feature_meta_bg(fs->super) &&
+           !(flags & EXT2_FLAG_IMAGE_FILE)) {
                first_meta_bg = fs->super->s_first_meta_bg;
                if (first_meta_bg > fs->desc_blocks)
                        first_meta_bg = fs->desc_blocks;
@@ -462,7 +481,7 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
                if (fs->flags & EXT2_FLAG_RW)
                        ext2fs_mark_super_dirty(fs);
        }
-
+skip_read_bg:
        if (ext2fs_has_feature_mmp(fs->super) &&
            !(flags & EXT2_FLAG_SKIP_MMP) &&
            (flags & (EXT2_FLAG_RW | EXT2_FLAG_EXCLUSIVE))) {
@@ -474,6 +493,19 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
                }
        }
 
+       if (fs->flags & EXT2_FLAG_SHARE_DUP) {
+               fs->block_sha_map = ext2fs_hashmap_create(ext2fs_djb2_hash,
+                                       block_sha_map_free_entry, 4096);
+               if (!fs->block_sha_map) {
+                       retval = EXT2_ET_NO_MEMORY;
+                       goto cleanup;
+               }
+               ext2fs_set_feature_shared_blocks(fs->super);
+       }
+
+       if (ext2fs_has_feature_casefold(fs->super))
+               fs->encoding = ext2fs_load_nls_table(fs->super->s_encoding);
+
        fs->flags &= ~EXT2_FLAG_NOFREE_ON_ERROR;
        *ret_fs = fs;