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path: root/lib/sqfs/data_reader.c
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2022-03-30Fix: guard against potential overflow in file size calculationDavid Oberhollenzer
The block_count is a size_t, so on 32 bit platforms the multiplication might be truncated before the comparison with filesz. On 64 bit platforms, it could potentially also overflow the 64 bit bounds of the data type. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-06-20Fix block bounds checking in libsquashfs data readerDavid Oberhollenzer
Instead of doing the fragile size comparison in both loops, simply bail from the function if offset is out of bounds, clamp the size to the available range of the file and abail if it is zero. As a result, a lot of checks can be removed and the function will not return data beyond EOF. This problem occoured with files that have a short last block instead of a fragment. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-06-11Add flags to functions that might logically be expanded in the futureDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-03-04Add a generic copying mechanism to sqfs_object_tDavid Oberhollenzer
This patch adds a deep-copy callback to sqfs_object_t and removes the copying mechanism from sqfs_compressor_t. This is also interesting for other types. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-02-23Unify the payload counters in the sqfs_inode_generic_tDavid Oberhollenzer
Instead of having seperate counters for blocks, dir index bytes and having to fiddle out the link target size, simply use a single value that stores the number of payload bytes used. A seperate "payload bytes available" is used for dynamically growing inodes during processing. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-02-12Implement a more explicit object systemDavid Oberhollenzer
Make every dynamically allocated, opaque data structure inherit from a common sqfs_object_t structure with common entry points (e.g. destroy). This removes tons of public API functions and replaces them with a simple sqfs_destroy instead. If semantics of the (until now implicit) object system need to be extended, it can be much more conveniantely done this way. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-02-12Remove usage of sqfs_block_t from block readerDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-02-12Fix data reader return codesDavid Oberhollenzer
Return an error number as document instead of throwing -1. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-01-24Cleanup: use the frag table data type in the data readerDavid Oberhollenzer
Instead of doing everything by manually. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-01-19Cleanup: remove the payload pointers from sqfs_inode_generic_tDavid Oberhollenzer
There are 3 types of extra payload: - Directory index - File block sizes - Symlink target This commit removes the type specific pointers and modifies the code to use the payload area directly. To simplify the file block case and mitigate alignment issues, the type of the extra field is changed to sqfs_u32. For symlink target, the extra field can simply be cast to a character pointer (it had to be cast anyway for most uses). For block sizes, probably the most common usecase, it can be used as is. For directory indices, there is a helper function anyway. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-11-25Cleanup: move overflow safe alloc code into libsquashfsDavid Oberhollenzer
There were only a hand full of instances outside libsquashfs that used the alloc code. In most cases, the thing allocated hat its size derived from something already in memory anyway, so it is safe to assume its size fits into a size_t. At the same time, the opencoded Windows path conversion functions are all unified into a single helper function. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-10-07Cleanup: move libutil related headers to "util" sub directoryDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-09-29Cleanup: rename "compress.h" to "compressor.h"David Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-09-27Remove use of ssize_t from library APIDavid Oberhollenzer
ssize_t is only available on POSIX platforms and even there it is only defined to hold at least -1 in the range of negative numbers. This commit replaces ssize_t return types with sqfs_s32 and the coresponding function arguments with sqfs_u32. Because the range of positiv numbers for a signed 32 bit number is only half that of the unsigned version, additional checks have to be added. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-09-27Cleanup: replace fixed with data types with typedefsDavid Oberhollenzer
This is a fully automated search and replace, i.e. I ran this: git grep -l uint8_t | xargs sed -i 's/uint8_t/sqfs_u8/g' git grep -l uint16_t | xargs sed -i 's/uint16_t/sqfs_u16/g' git grep -l uint32_t | xargs sed -i 's/uint32_t/sqfs_u32/g' git grep -l uint64_t | xargs sed -i 's/uint64_t/sqfs_u64/g' git grep -l int8_t | xargs sed -i 's/int8_t/sqfs_s8/g' git grep -l int16_t | xargs sed -i 's/int16_t/sqfs_s16/g' git grep -l int32_t | xargs sed -i 's/int32_t/sqfs_s32/g' git grep -l int64_t | xargs sed -i 's/int64_t/sqfs_s64/g' and than added the appropriate definitions to sqfs/predef.h The whole point being better compatibillity with platforms that may not have an stdint.h with the propper definitions. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-09-27Cleanup: merge data.h into block.hDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-09-25Move sqfs_block_t to its own headerDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-09-25Rename block processor to sqfs_data_writer_tDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-09-24Fix memory and pointer leaks in data reader error pathsDavid Oberhollenzer
Make sure that the block cache pointers are reset to NULL after freeing them, the get_block function does not update them on failure. Also, make sure all error paths in the get_block function actually clean up the allocated memory. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-09-22Add helper functions for working with inodesDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-09-20Integrate the data reader into libsquashfsDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-08-31Split libsquashfs.a into low seperate librariesDavid Oberhollenzer
The idea is to make libsquashfs.a independend of libfstree.a, so it becomes a general purpose squashfs manipulation library. All the high level glue code for libfstree.a and utilites that are overly specific with to tools are moved to a seperate librarby. This commit makes the first step by moving the stuff with dependencies on libfstree to a seperate library. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-08-23Do bounds checking in metadata readerDavid Oberhollenzer
In all cases where metadata blocks are read, we can roughly (in some cases even preciesly) say in what range those metadata blocks will be, so it makes sense to throw an error if an attempt is made to wander outside this range. Furthermore, when reading from an uncompressed block, it is more reasonable to check against the actual block bounds than to padd it with 0 bytes. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-08-23Some simple search/replace cases for allocationDavid Oberhollenzer
This commit exchanges some malloc(x + y * z) patterns that can be found with a simple git grep and are obvious for the new wrappers. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-08-07Add pread(2) like function to data_readerDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-08-07Fix forward seek when unpacking sparse filesDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-08-07Fix zero padding of extracted data blocksDavid Oberhollenzer
Only padd it if the *extracted* size is less then block size. Doing it with the compressed size results in garbled blocks. Especially because most of them are less than block size when compressed. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-08-05cleanup data readerDavid Oberhollenzer
- Split block reading code out from "dump_blocks" into precache_data_block, similar to precache_fragment_block - Merge the code paths for fragment/data block reading and uncompression Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-30Add propper copyright headers to all source filesDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-28Fix: return the correct value from data_reader_createDavid Oberhollenzer
Cut & paste misshap after mergining with fragment reader: If there are no fragments, data_reader_create should return the data reader, not 0! Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-28Add general purpose flags field to file_info_tDavid Oberhollenzer
Simplifies some task if we can just add a flag that a file has a framgent or that it has already been detected as a duplicate. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-28Add fragment and block checksum fields to file_info_tDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-28Merge remaining code of fragment reader into data readerDavid Oberhollenzer
After the table read unification, there wasn't much left of the fragment reader and the remains could easily be moved over to the data reader. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-28Split data_reader_dump_file into smaller functionsDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-25Replace reads in squashfs with positional readsDavid Oberhollenzer
In most cases, we know exactely where the data that we want to read is on disk, so instead of using read() on the squashfs (or lseek + read), the code can in many places be cleaned up to use the pread wrapper read_data_at instead. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-24Enable largefile supportMatt Turner
Requires that config.h be included before other headers, since the macro _FILE_OFFSET_BITS changes the definitions of things like 'struct stat'. I chose to simply include it at the top of every C file and at immediately after the double-inclusion guards of every header. Signed-off-by: Matt Turner <mattst88@gmail.com> Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-21cleanup: remove left over, unused assignmentDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-20Make raw fragment table accessible through fragment/data readersDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-16cleanup: move error handling into read_retryDavid Oberhollenzer
If read_retry fails to read the expected amount of data (EOF or otherwise), it is almost always an error. This commit renames read_retry to read_data and moves error handling into the function, making a lot of error handling code redundant. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-16cleanup: move error handling into write_retryDavid Oberhollenzer
If write_retry fails to write everything, it is *always* an error. This commit renames write_retry to write_data and moves error handling into the function, making a lot of error handling code redundant. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-07-12Add generic support for reading files without fragmentsDavid Oberhollenzer
This commit extends the special case handling for sparse files to generically support reading files that don't have a fragment but instead have a trunkated final block. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-06-28Add support for unpacking sparse files as sparse filesDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-06-28Add support for packing sparse filesDavid Oberhollenzer
This commit adds support for packing sparse files into squashfs images as follows: - In the data writer: simply detect zero blocks and write a zero to the block size field and don't emit any data. Record the number of bytes saved this way. For fragments, set the fragment offset to invalid. - In the inode writer: write out the number of bytes saved for sparse files. If there should be a fragment but there is none, append a block count of 0. - In the data reader: if the block size is 0, read nothing from disk and emit an empty block. Do the same if the fragment is missing. - In the inode reader: restore the number of bytes saved for sparse files. The sparse files can be packed and unpacked, but the unpacking will not create sparse files for now. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-06-11Move file extraction code to generic data_reader_t in libsquashfs.aDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>