wok-current diff linux-libre/stuff/001-squashfs-decompressors-add-xz-decompressor-module.patch @ rev 23325
updated perl-extutils-makemaker (7.34 -> 7.44)
author | Hans-G?nter Theisgen |
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date | Mon Mar 30 17:08:23 2020 +0100 (2020-03-30) |
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1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 1.2 +++ b/linux-libre/stuff/001-squashfs-decompressors-add-xz-decompressor-module.patch Mon Mar 30 17:08:23 2020 +0100 1.3 @@ -0,0 +1,3934 @@ 1.4 +From: Lasse Collin <lasse.collin@tukaani.org> 1.5 +Date: Thu, 2 Dec 2010 19:14:19 +0000 (+0200) 1.6 +Subject: Decompressors: Add XZ decompressor module 1.7 +X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Fpkl%2Fsquashfs-xz.git;a=commitdiff_plain;h=3dbc3fe7878e53b43064a12d4ab31ca4c18ce85f 1.8 + 1.9 +Decompressors: Add XZ decompressor module 1.10 + 1.11 +In userspace, the .lzma format has become mostly a legacy 1.12 +file format that got superseded by the .xz format. Similarly, 1.13 +LZMA Utils was superseded by XZ Utils. 1.14 + 1.15 +These patches add support for XZ decompression into 1.16 +the kernel. Most of the code is as is from XZ Embedded 1.17 +<http://tukaani.org/xz/embedded.html>. It was written for 1.18 +the Linux kernel but is usable in other projects too. 1.19 + 1.20 +Advantages of XZ over the current LZMA code in the kernel: 1.21 + - Nice API that can be used by other kernel modules; it's 1.22 + not limited to kernel, initramfs, and initrd decompression. 1.23 + - Integrity check support (CRC32) 1.24 + - BCJ filters improve compression of executable code on 1.25 + certain architectures. These together with LZMA2 can 1.26 + produce a few percent smaller kernel or Squashfs images 1.27 + than plain LZMA without making the decompression slower. 1.28 + 1.29 +This patch: Add the main decompression code (xz_dec), testing 1.30 +module (xz_dec_test), wrapper script (xz_wrap.sh) for the xz 1.31 +command line tool, and documentation. The xz_dec module is 1.32 +enough to have a usable XZ decompressor e.g. for Squashfs. 1.33 + 1.34 +Signed-off-by: Lasse Collin <lasse.collin@tukaani.org> 1.35 +--- 1.36 + 1.37 +diff --git a/Documentation/xz.txt b/Documentation/xz.txt 1.38 +new file mode 100644 1.39 +index 0000000..68329ac 1.40 +--- /dev/null 1.41 ++++ b/Documentation/xz.txt 1.42 +@@ -0,0 +1,122 @@ 1.43 ++ 1.44 ++XZ data compression in Linux 1.45 ++============================ 1.46 ++ 1.47 ++Introduction 1.48 ++ 1.49 ++ XZ is a general purpose data compression format with high compression 1.50 ++ ratio and relatively fast decompression. The primary compression 1.51 ++ algorithm (filter) is LZMA2. Additional filters can be used to improve 1.52 ++ compression ratio even further. E.g. Branch/Call/Jump (BCJ) filters 1.53 ++ improve compression ratio of executable data. 1.54 ++ 1.55 ++ The XZ decompressor in Linux is called XZ Embedded. It supports 1.56 ++ the LZMA2 filter and optionally also BCJ filters. CRC32 is supported 1.57 ++ for integrity checking. The home page of XZ Embedded is at 1.58 ++ <http://tukaani.org/xz/embedded.html>, where you can find the 1.59 ++ latest version and also information about using the code outside 1.60 ++ the Linux kernel. 1.61 ++ 1.62 ++ For userspace, XZ Utils provide a zlib-like compression library 1.63 ++ and a gzip-like command line tool. XZ Utils can be downloaded from 1.64 ++ <http://tukaani.org/xz/>. 1.65 ++ 1.66 ++XZ related components in the kernel 1.67 ++ 1.68 ++ The xz_dec module provides XZ decompressor with single-call (buffer 1.69 ++ to buffer) and multi-call (stateful) APIs. The usage of the xz_dec 1.70 ++ module is documented in include/linux/xz.h. 1.71 ++ 1.72 ++ The xz_dec_test module is for testing xz_dec. xz_dec_test is not 1.73 ++ useful unless you are hacking the XZ decompressor. xz_dec_test 1.74 ++ allocates a char device major dynamically to which one can write 1.75 ++ .xz files from userspace. The decompressed output is thrown away. 1.76 ++ Keep an eye on dmesg to see diagnostics printed by xz_dec_test. 1.77 ++ See the xz_dec_test source code for the details. 1.78 ++ 1.79 ++ For decompressing the kernel image, initramfs, and initrd, there 1.80 ++ is a wrapper function in lib/decompress_unxz.c. Its API is the 1.81 ++ same as in other decompress_*.c files, which is defined in 1.82 ++ include/linux/decompress/generic.h. 1.83 ++ 1.84 ++ scripts/xz_wrap.sh is a wrapper for the xz command line tool found 1.85 ++ from XZ Utils. The wrapper sets compression options to values suitable 1.86 ++ for compressing the kernel image. 1.87 ++ 1.88 ++ For kernel makefiles, two commands are provided for use with 1.89 ++ $(call if_needed). The kernel image should be compressed with 1.90 ++ $(call if_needed,xzkern) which will use a BCJ filter and a big LZMA2 1.91 ++ dictionary. It will also append a four-byte trailer containing the 1.92 ++ uncompressed size of the file, which is needed by the boot code. 1.93 ++ Other things should be compressed with $(call if_needed,xzmisc) 1.94 ++ which will use no BCJ filter and 1 MiB LZMA2 dictionary. 1.95 ++ 1.96 ++Notes on compression options 1.97 ++ 1.98 ++ Since the XZ Embedded supports only streams with no integrity check or 1.99 ++ CRC32, make sure that you don't use some other integrity check type 1.100 ++ when encoding files that are supposed to be decoded by the kernel. With 1.101 ++ liblzma, you need to use either LZMA_CHECK_NONE or LZMA_CHECK_CRC32 1.102 ++ when encoding. With the xz command line tool, use --check=none or 1.103 ++ --check=crc32. 1.104 ++ 1.105 ++ Using CRC32 is strongly recommended unless there is some other layer 1.106 ++ which will verify the integrity of the uncompressed data anyway. 1.107 ++ Double checking the integrity would probably be waste of CPU cycles. 1.108 ++ Note that the headers will always have a CRC32 which will be validated 1.109 ++ by the decoder; you can only change the integrity check type (or 1.110 ++ disable it) for the actual uncompressed data. 1.111 ++ 1.112 ++ In userspace, LZMA2 is typically used with dictionary sizes of several 1.113 ++ megabytes. The decoder needs to have the dictionary in RAM, thus big 1.114 ++ dictionaries cannot be used for files that are intended to be decoded 1.115 ++ by the kernel. 1 MiB is probably the maximum reasonable dictionary 1.116 ++ size for in-kernel use (maybe more is OK for initramfs). The presets 1.117 ++ in XZ Utils may not be optimal when creating files for the kernel, 1.118 ++ so don't hesitate to use custom settings. Example: 1.119 ++ 1.120 ++ xz --check=crc32 --lzma2=dict=512KiB inputfile 1.121 ++ 1.122 ++ An exception to above dictionary size limitation is when the decoder 1.123 ++ is used in single-call mode. Decompressing the kernel itself is an 1.124 ++ example of this situation. In single-call mode, the memory usage 1.125 ++ doesn't depend on the dictionary size, and it is perfectly fine to 1.126 ++ use a big dictionary: for maximum compression, the dictionary should 1.127 ++ be at least as big as the uncompressed data itself. 1.128 ++ 1.129 ++Future plans 1.130 ++ 1.131 ++ Creating a limited XZ encoder may be considered if people think it is 1.132 ++ useful. LZMA2 is slower to compress than e.g. Deflate or LZO even at 1.133 ++ the fastest settings, so it isn't clear if LZMA2 encoder is wanted 1.134 ++ into the kernel. 1.135 ++ 1.136 ++ Support for limited random-access reading is planned for the 1.137 ++ decompression code. I don't know if it could have any use in the 1.138 ++ kernel, but I know that it would be useful in some embedded projects 1.139 ++ outside the Linux kernel. 1.140 ++ 1.141 ++Conformance to the .xz file format specification 1.142 ++ 1.143 ++ There are a couple of corner cases where things have been simplified 1.144 ++ at expense of detecting errors as early as possible. These should not 1.145 ++ matter in practice all, since they don't cause security issues. But 1.146 ++ it is good to know this if testing the code e.g. with the test files 1.147 ++ from XZ Utils. 1.148 ++ 1.149 ++Reporting bugs 1.150 ++ 1.151 ++ Before reporting a bug, please check that it's not fixed already 1.152 ++ at upstream. See <http://tukaani.org/xz/embedded.html> to get the 1.153 ++ latest code. 1.154 ++ 1.155 ++ Report bugs to <lasse.collin@tukaani.org> or visit #tukaani on 1.156 ++ Freenode and talk to Larhzu. I don't actively read LKML or other 1.157 ++ kernel-related mailing lists, so if there's something I should know, 1.158 ++ you should email to me personally or use IRC. 1.159 ++ 1.160 ++ Don't bother Igor Pavlov with questions about the XZ implementation 1.161 ++ in the kernel or about XZ Utils. While these two implementations 1.162 ++ include essential code that is directly based on Igor Pavlov's code, 1.163 ++ these implementations aren't maintained nor supported by him. 1.164 ++ 1.165 +diff --git a/include/linux/xz.h b/include/linux/xz.h 1.166 +new file mode 100644 1.167 +index 0000000..64cffa6 1.168 +--- /dev/null 1.169 ++++ b/include/linux/xz.h 1.170 +@@ -0,0 +1,264 @@ 1.171 ++/* 1.172 ++ * XZ decompressor 1.173 ++ * 1.174 ++ * Authors: Lasse Collin <lasse.collin@tukaani.org> 1.175 ++ * Igor Pavlov <http://7-zip.org/> 1.176 ++ * 1.177 ++ * This file has been put into the public domain. 1.178 ++ * You can do whatever you want with this file. 1.179 ++ */ 1.180 ++ 1.181 ++#ifndef XZ_H 1.182 ++#define XZ_H 1.183 ++ 1.184 ++#ifdef __KERNEL__ 1.185 ++# include <linux/stddef.h> 1.186 ++# include <linux/types.h> 1.187 ++#else 1.188 ++# include <stddef.h> 1.189 ++# include <stdint.h> 1.190 ++#endif 1.191 ++ 1.192 ++/* In Linux, this is used to make extern functions static when needed. */ 1.193 ++#ifndef XZ_EXTERN 1.194 ++# define XZ_EXTERN extern 1.195 ++#endif 1.196 ++ 1.197 ++/** 1.198 ++ * enum xz_mode - Operation mode 1.199 ++ * 1.200 ++ * @XZ_SINGLE: Single-call mode. This uses less RAM than 1.201 ++ * than multi-call modes, because the LZMA2 1.202 ++ * dictionary doesn't need to be allocated as 1.203 ++ * part of the decoder state. All required data 1.204 ++ * structures are allocated at initialization, 1.205 ++ * so xz_dec_run() cannot return XZ_MEM_ERROR. 1.206 ++ * @XZ_PREALLOC: Multi-call mode with preallocated LZMA2 1.207 ++ * dictionary buffer. All data structures are 1.208 ++ * allocated at initialization, so xz_dec_run() 1.209 ++ * cannot return XZ_MEM_ERROR. 1.210 ++ * @XZ_DYNALLOC: Multi-call mode. The LZMA2 dictionary is 1.211 ++ * allocated once the required size has been 1.212 ++ * parsed from the stream headers. If the 1.213 ++ * allocation fails, xz_dec_run() will return 1.214 ++ * XZ_MEM_ERROR. 1.215 ++ * 1.216 ++ * It is possible to enable support only for a subset of the above 1.217 ++ * modes at compile time by defining XZ_DEC_SINGLE, XZ_DEC_PREALLOC, 1.218 ++ * or XZ_DEC_DYNALLOC. The xz_dec kernel module is always compiled 1.219 ++ * with support for all operation modes, but the preboot code may 1.220 ++ * be built with fewer features to minimize code size. 1.221 ++ */ 1.222 ++enum xz_mode { 1.223 ++ XZ_SINGLE, 1.224 ++ XZ_PREALLOC, 1.225 ++ XZ_DYNALLOC 1.226 ++}; 1.227 ++ 1.228 ++/** 1.229 ++ * enum xz_ret - Return codes 1.230 ++ * @XZ_OK: Everything is OK so far. More input or more 1.231 ++ * output space is required to continue. This 1.232 ++ * return code is possible only in multi-call mode 1.233 ++ * (XZ_PREALLOC or XZ_DYNALLOC). 1.234 ++ * @XZ_STREAM_END: Operation finished successfully. 1.235 ++ * @XZ_UNSUPPORTED_CHECK: Integrity check type is not supported. Decoding 1.236 ++ * is still possible in multi-call mode by simply 1.237 ++ * calling xz_dec_run() again. 1.238 ++ * Note that this return value is used only if 1.239 ++ * XZ_DEC_ANY_CHECK was defined at build time, 1.240 ++ * which is not used in the kernel. Unsupported 1.241 ++ * check types return XZ_OPTIONS_ERROR if 1.242 ++ * XZ_DEC_ANY_CHECK was not defined at build time. 1.243 ++ * @XZ_MEM_ERROR: Allocating memory failed. This return code is 1.244 ++ * possible only if the decoder was initialized 1.245 ++ * with XZ_DYNALLOC. The amount of memory that was 1.246 ++ * tried to be allocated was no more than the 1.247 ++ * dict_max argument given to xz_dec_init(). 1.248 ++ * @XZ_MEMLIMIT_ERROR: A bigger LZMA2 dictionary would be needed than 1.249 ++ * allowed by the dict_max argument given to 1.250 ++ * xz_dec_init(). This return value is possible 1.251 ++ * only in multi-call mode (XZ_PREALLOC or 1.252 ++ * XZ_DYNALLOC); the single-call mode (XZ_SINGLE) 1.253 ++ * ignores the dict_max argument. 1.254 ++ * @XZ_FORMAT_ERROR: File format was not recognized (wrong magic 1.255 ++ * bytes). 1.256 ++ * @XZ_OPTIONS_ERROR: This implementation doesn't support the requested 1.257 ++ * compression options. In the decoder this means 1.258 ++ * that the header CRC32 matches, but the header 1.259 ++ * itself specifies something that we don't support. 1.260 ++ * @XZ_DATA_ERROR: Compressed data is corrupt. 1.261 ++ * @XZ_BUF_ERROR: Cannot make any progress. Details are slightly 1.262 ++ * different between multi-call and single-call 1.263 ++ * mode; more information below. 1.264 ++ * 1.265 ++ * In multi-call mode, XZ_BUF_ERROR is returned when two consecutive calls 1.266 ++ * to XZ code cannot consume any input and cannot produce any new output. 1.267 ++ * This happens when there is no new input available, or the output buffer 1.268 ++ * is full while at least one output byte is still pending. Assuming your 1.269 ++ * code is not buggy, you can get this error only when decoding a compressed 1.270 ++ * stream that is truncated or otherwise corrupt. 1.271 ++ * 1.272 ++ * In single-call mode, XZ_BUF_ERROR is returned only when the output buffer 1.273 ++ * is too small or the compressed input is corrupt in a way that makes the 1.274 ++ * decoder produce more output than the caller expected. When it is 1.275 ++ * (relatively) clear that the compressed input is truncated, XZ_DATA_ERROR 1.276 ++ * is used instead of XZ_BUF_ERROR. 1.277 ++ */ 1.278 ++enum xz_ret { 1.279 ++ XZ_OK, 1.280 ++ XZ_STREAM_END, 1.281 ++ XZ_UNSUPPORTED_CHECK, 1.282 ++ XZ_MEM_ERROR, 1.283 ++ XZ_MEMLIMIT_ERROR, 1.284 ++ XZ_FORMAT_ERROR, 1.285 ++ XZ_OPTIONS_ERROR, 1.286 ++ XZ_DATA_ERROR, 1.287 ++ XZ_BUF_ERROR 1.288 ++}; 1.289 ++ 1.290 ++/** 1.291 ++ * struct xz_buf - Passing input and output buffers to XZ code 1.292 ++ * @in: Beginning of the input buffer. This may be NULL if and only 1.293 ++ * if in_pos is equal to in_size. 1.294 ++ * @in_pos: Current position in the input buffer. This must not exceed 1.295 ++ * in_size. 1.296 ++ * @in_size: Size of the input buffer 1.297 ++ * @out: Beginning of the output buffer. This may be NULL if and only 1.298 ++ * if out_pos is equal to out_size. 1.299 ++ * @out_pos: Current position in the output buffer. This must not exceed 1.300 ++ * out_size. 1.301 ++ * @out_size: Size of the output buffer 1.302 ++ * 1.303 ++ * Only the contents of the output buffer from out[out_pos] onward, and 1.304 ++ * the variables in_pos and out_pos are modified by the XZ code. 1.305 ++ */ 1.306 ++struct xz_buf { 1.307 ++ const uint8_t *in; 1.308 ++ size_t in_pos; 1.309 ++ size_t in_size; 1.310 ++ 1.311 ++ uint8_t *out; 1.312 ++ size_t out_pos; 1.313 ++ size_t out_size; 1.314 ++}; 1.315 ++ 1.316 ++/** 1.317 ++ * struct xz_dec - Opaque type to hold the XZ decoder state 1.318 ++ */ 1.319 ++struct xz_dec; 1.320 ++ 1.321 ++/** 1.322 ++ * xz_dec_init() - Allocate and initialize a XZ decoder state 1.323 ++ * @mode: Operation mode 1.324 ++ * @dict_max: Maximum size of the LZMA2 dictionary (history buffer) for 1.325 ++ * multi-call decoding. This is ignored in single-call mode 1.326 ++ * (mode == XZ_SINGLE). LZMA2 dictionary is always 2^n bytes 1.327 ++ * or 2^n + 2^(n-1) bytes (the latter sizes are less common 1.328 ++ * in practice), so other values for dict_max don't make sense. 1.329 ++ * In the kernel, dictionary sizes of 64 KiB, 128 KiB, 256 KiB, 1.330 ++ * 512 KiB, and 1 MiB are probably the only reasonable values, 1.331 ++ * except for kernel and initramfs images where a bigger 1.332 ++ * dictionary can be fine and useful. 1.333 ++ * 1.334 ++ * Single-call mode (XZ_SINGLE): xz_dec_run() decodes the whole stream at 1.335 ++ * once. The caller must provide enough output space or the decoding will 1.336 ++ * fail. The output space is used as the dictionary buffer, which is why 1.337 ++ * there is no need to allocate the dictionary as part of the decoder's 1.338 ++ * internal state. 1.339 ++ * 1.340 ++ * Because the output buffer is used as the workspace, streams encoded using 1.341 ++ * a big dictionary are not a problem in single-call mode. It is enough that 1.342 ++ * the output buffer is big enough to hold the actual uncompressed data; it 1.343 ++ * can be smaller than the dictionary size stored in the stream headers. 1.344 ++ * 1.345 ++ * Multi-call mode with preallocated dictionary (XZ_PREALLOC): dict_max bytes 1.346 ++ * of memory is preallocated for the LZMA2 dictionary. This way there is no 1.347 ++ * risk that xz_dec_run() could run out of memory, since xz_dec_run() will 1.348 ++ * never allocate any memory. Instead, if the preallocated dictionary is too 1.349 ++ * small for decoding the given input stream, xz_dec_run() will return 1.350 ++ * XZ_MEMLIMIT_ERROR. Thus, it is important to know what kind of data will be 1.351 ++ * decoded to avoid allocating excessive amount of memory for the dictionary. 1.352 ++ * 1.353 ++ * Multi-call mode with dynamically allocated dictionary (XZ_DYNALLOC): 1.354 ++ * dict_max specifies the maximum allowed dictionary size that xz_dec_run() 1.355 ++ * may allocate once it has parsed the dictionary size from the stream 1.356 ++ * headers. This way excessive allocations can be avoided while still 1.357 ++ * limiting the maximum memory usage to a sane value to prevent running the 1.358 ++ * system out of memory when decompressing streams from untrusted sources. 1.359 ++ * 1.360 ++ * On success, xz_dec_init() returns a pointer to struct xz_dec, which is 1.361 ++ * ready to be used with xz_dec_run(). If memory allocation fails, 1.362 ++ * xz_dec_init() returns NULL. 1.363 ++ */ 1.364 ++XZ_EXTERN struct xz_dec *xz_dec_init(enum xz_mode mode, uint32_t dict_max); 1.365 ++ 1.366 ++/** 1.367 ++ * xz_dec_run() - Run the XZ decoder 1.368 ++ * @s: Decoder state allocated using xz_dec_init() 1.369 ++ * @b: Input and output buffers 1.370 ++ * 1.371 ++ * The possible return values depend on build options and operation mode. 1.372 ++ * See enum xz_ret for details. 1.373 ++ * 1.374 ++ * Note that if an error occurs in single-call mode (return value is not 1.375 ++ * XZ_STREAM_END), b->in_pos and b->out_pos are not modified and the 1.376 ++ * contents of the output buffer from b->out[b->out_pos] onward are 1.377 ++ * undefined. This is true even after XZ_BUF_ERROR, because with some filter 1.378 ++ * chains, there may be a second pass over the output buffer, and this pass 1.379 ++ * cannot be properly done if the output buffer is truncated. Thus, you 1.380 ++ * cannot give the single-call decoder a too small buffer and then expect to 1.381 ++ * get that amount valid data from the beginning of the stream. You must use 1.382 ++ * the multi-call decoder if you don't want to uncompress the whole stream. 1.383 ++ */ 1.384 ++XZ_EXTERN enum xz_ret xz_dec_run(struct xz_dec *s, struct xz_buf *b); 1.385 ++ 1.386 ++/** 1.387 ++ * xz_dec_reset() - Reset an already allocated decoder state 1.388 ++ * @s: Decoder state allocated using xz_dec_init() 1.389 ++ * 1.390 ++ * This function can be used to reset the multi-call decoder state without 1.391 ++ * freeing and reallocating memory with xz_dec_end() and xz_dec_init(). 1.392 ++ * 1.393 ++ * In single-call mode, xz_dec_reset() is always called in the beginning of 1.394 ++ * xz_dec_run(). Thus, explicit call to xz_dec_reset() is useful only in 1.395 ++ * multi-call mode. 1.396 ++ */ 1.397 ++XZ_EXTERN void xz_dec_reset(struct xz_dec *s); 1.398 ++ 1.399 ++/** 1.400 ++ * xz_dec_end() - Free the memory allocated for the decoder state 1.401 ++ * @s: Decoder state allocated using xz_dec_init(). If s is NULL, 1.402 ++ * this function does nothing. 1.403 ++ */ 1.404 ++XZ_EXTERN void xz_dec_end(struct xz_dec *s); 1.405 ++ 1.406 ++/* 1.407 ++ * Standalone build (userspace build or in-kernel build for boot time use) 1.408 ++ * needs a CRC32 implementation. For normal in-kernel use, kernel's own 1.409 ++ * CRC32 module is used instead, and users of this module don't need to 1.410 ++ * care about the functions below. 1.411 ++ */ 1.412 ++#ifndef XZ_INTERNAL_CRC32 1.413 ++# ifdef __KERNEL__ 1.414 ++# define XZ_INTERNAL_CRC32 0 1.415 ++# else 1.416 ++# define XZ_INTERNAL_CRC32 1 1.417 ++# endif 1.418 ++#endif 1.419 ++ 1.420 ++#if XZ_INTERNAL_CRC32 1.421 ++/* 1.422 ++ * This must be called before any other xz_* function to initialize 1.423 ++ * the CRC32 lookup table. 1.424 ++ */ 1.425 ++XZ_EXTERN void xz_crc32_init(void); 1.426 ++ 1.427 ++/* 1.428 ++ * Update CRC32 value using the polynomial from IEEE-802.3. To start a new 1.429 ++ * calculation, the third argument must be zero. To continue the calculation, 1.430 ++ * the previously returned value is passed as the third argument. 1.431 ++ */ 1.432 ++XZ_EXTERN uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc); 1.433 ++#endif 1.434 ++#endif 1.435 +diff --git a/lib/Kconfig b/lib/Kconfig 1.436 +index fa9bf2c..6090314 100644 1.437 +--- a/lib/Kconfig 1.438 ++++ b/lib/Kconfig 1.439 +@@ -106,6 +106,8 @@ config LZO_COMPRESS 1.440 + config LZO_DECOMPRESS 1.441 + tristate 1.442 + 1.443 ++source "lib/xz/Kconfig" 1.444 ++ 1.445 + # 1.446 + # These all provide a common interface (hence the apparent duplication with 1.447 + # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) 1.448 +diff --git a/lib/Makefile b/lib/Makefile 1.449 +index e6a3763..f2f98dd 100644 1.450 +--- a/lib/Makefile 1.451 ++++ b/lib/Makefile 1.452 +@@ -69,6 +69,7 @@ obj-$(CONFIG_ZLIB_DEFLATE) += zlib_deflate/ 1.453 + obj-$(CONFIG_REED_SOLOMON) += reed_solomon/ 1.454 + obj-$(CONFIG_LZO_COMPRESS) += lzo/ 1.455 + obj-$(CONFIG_LZO_DECOMPRESS) += lzo/ 1.456 ++obj-$(CONFIG_XZ_DEC) += xz/ 1.457 + obj-$(CONFIG_RAID6_PQ) += raid6/ 1.458 + 1.459 + lib-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o 1.460 +diff --git a/lib/xz/Kconfig b/lib/xz/Kconfig 1.461 +new file mode 100644 1.462 +index 0000000..e3b6e18 1.463 +--- /dev/null 1.464 ++++ b/lib/xz/Kconfig 1.465 +@@ -0,0 +1,59 @@ 1.466 ++config XZ_DEC 1.467 ++ tristate "XZ decompression support" 1.468 ++ select CRC32 1.469 ++ help 1.470 ++ LZMA2 compression algorithm and BCJ filters are supported using 1.471 ++ the .xz file format as the container. For integrity checking, 1.472 ++ CRC32 is supported. See Documentation/xz.txt for more information. 1.473 ++ 1.474 ++config XZ_DEC_X86 1.475 ++ bool "x86 BCJ filter decoder" if EMBEDDED 1.476 ++ default y 1.477 ++ depends on XZ_DEC 1.478 ++ select XZ_DEC_BCJ 1.479 ++ 1.480 ++config XZ_DEC_POWERPC 1.481 ++ bool "PowerPC BCJ filter decoder" if EMBEDDED 1.482 ++ default y 1.483 ++ depends on XZ_DEC 1.484 ++ select XZ_DEC_BCJ 1.485 ++ 1.486 ++config XZ_DEC_IA64 1.487 ++ bool "IA-64 BCJ filter decoder" if EMBEDDED 1.488 ++ default y 1.489 ++ depends on XZ_DEC 1.490 ++ select XZ_DEC_BCJ 1.491 ++ 1.492 ++config XZ_DEC_ARM 1.493 ++ bool "ARM BCJ filter decoder" if EMBEDDED 1.494 ++ default y 1.495 ++ depends on XZ_DEC 1.496 ++ select XZ_DEC_BCJ 1.497 ++ 1.498 ++config XZ_DEC_ARMTHUMB 1.499 ++ bool "ARM-Thumb BCJ filter decoder" if EMBEDDED 1.500 ++ default y 1.501 ++ depends on XZ_DEC 1.502 ++ select XZ_DEC_BCJ 1.503 ++ 1.504 ++config XZ_DEC_SPARC 1.505 ++ bool "SPARC BCJ filter decoder" if EMBEDDED 1.506 ++ default y 1.507 ++ depends on XZ_DEC 1.508 ++ select XZ_DEC_BCJ 1.509 ++ 1.510 ++config XZ_DEC_BCJ 1.511 ++ bool 1.512 ++ default n 1.513 ++ 1.514 ++config XZ_DEC_TEST 1.515 ++ tristate "XZ decompressor tester" 1.516 ++ default n 1.517 ++ depends on XZ_DEC 1.518 ++ help 1.519 ++ This allows passing .xz files to the in-kernel XZ decoder via 1.520 ++ a character special file. It calculates CRC32 of the decompressed 1.521 ++ data and writes diagnostics to the system log. 1.522 ++ 1.523 ++ Unless you are developing the XZ decoder, you don't need this 1.524 ++ and should say N. 1.525 +diff --git a/lib/xz/Makefile b/lib/xz/Makefile 1.526 +new file mode 100644 1.527 +index 0000000..a7fa769 1.528 +--- /dev/null 1.529 ++++ b/lib/xz/Makefile 1.530 +@@ -0,0 +1,5 @@ 1.531 ++obj-$(CONFIG_XZ_DEC) += xz_dec.o 1.532 ++xz_dec-y := xz_dec_syms.o xz_dec_stream.o xz_dec_lzma2.o 1.533 ++xz_dec-$(CONFIG_XZ_DEC_BCJ) += xz_dec_bcj.o 1.534 ++ 1.535 ++obj-$(CONFIG_XZ_DEC_TEST) += xz_dec_test.o 1.536 +diff --git a/lib/xz/xz_crc32.c b/lib/xz/xz_crc32.c 1.537 +new file mode 100644 1.538 +index 0000000..34532d1 1.539 +--- /dev/null 1.540 ++++ b/lib/xz/xz_crc32.c 1.541 +@@ -0,0 +1,59 @@ 1.542 ++/* 1.543 ++ * CRC32 using the polynomial from IEEE-802.3 1.544 ++ * 1.545 ++ * Authors: Lasse Collin <lasse.collin@tukaani.org> 1.546 ++ * Igor Pavlov <http://7-zip.org/> 1.547 ++ * 1.548 ++ * This file has been put into the public domain. 1.549 ++ * You can do whatever you want with this file. 1.550 ++ */ 1.551 ++ 1.552 ++/* 1.553 ++ * This is not the fastest implementation, but it is pretty compact. 1.554 ++ * The fastest versions of xz_crc32() on modern CPUs without hardware 1.555 ++ * accelerated CRC instruction are 3-5 times as fast as this version, 1.556 ++ * but they are bigger and use more memory for the lookup table. 1.557 ++ */ 1.558 ++ 1.559 ++#include "xz_private.h" 1.560 ++ 1.561 ++/* 1.562 ++ * STATIC_RW_DATA is used in the pre-boot environment on some architectures. 1.563 ++ * See <linux/decompress/mm.h> for details. 1.564 ++ */ 1.565 ++#ifndef STATIC_RW_DATA 1.566 ++# define STATIC_RW_DATA static 1.567 ++#endif 1.568 ++ 1.569 ++STATIC_RW_DATA uint32_t xz_crc32_table[256]; 1.570 ++ 1.571 ++XZ_EXTERN void xz_crc32_init(void) 1.572 ++{ 1.573 ++ const uint32_t poly = 0xEDB88320; 1.574 ++ 1.575 ++ uint32_t i; 1.576 ++ uint32_t j; 1.577 ++ uint32_t r; 1.578 ++ 1.579 ++ for (i = 0; i < 256; ++i) { 1.580 ++ r = i; 1.581 ++ for (j = 0; j < 8; ++j) 1.582 ++ r = (r >> 1) ^ (poly & ~((r & 1) - 1)); 1.583 ++ 1.584 ++ xz_crc32_table[i] = r; 1.585 ++ } 1.586 ++ 1.587 ++ return; 1.588 ++} 1.589 ++ 1.590 ++XZ_EXTERN uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc) 1.591 ++{ 1.592 ++ crc = ~crc; 1.593 ++ 1.594 ++ while (size != 0) { 1.595 ++ crc = xz_crc32_table[*buf++ ^ (crc & 0xFF)] ^ (crc >> 8); 1.596 ++ --size; 1.597 ++ } 1.598 ++ 1.599 ++ return ~crc; 1.600 ++} 1.601 +diff --git a/lib/xz/xz_dec_bcj.c b/lib/xz/xz_dec_bcj.c 1.602 +new file mode 100644 1.603 +index 0000000..e51e255 1.604 +--- /dev/null 1.605 ++++ b/lib/xz/xz_dec_bcj.c 1.606 +@@ -0,0 +1,561 @@ 1.607 ++/* 1.608 ++ * Branch/Call/Jump (BCJ) filter decoders 1.609 ++ * 1.610 ++ * Authors: Lasse Collin <lasse.collin@tukaani.org> 1.611 ++ * Igor Pavlov <http://7-zip.org/> 1.612 ++ * 1.613 ++ * This file has been put into the public domain. 1.614 ++ * You can do whatever you want with this file. 1.615 ++ */ 1.616 ++ 1.617 ++#include "xz_private.h" 1.618 ++ 1.619 ++/* 1.620 ++ * The rest of the file is inside this ifdef. It makes things a little more 1.621 ++ * convenient when building without support for any BCJ filters. 1.622 ++ */ 1.623 ++#ifdef XZ_DEC_BCJ 1.624 ++ 1.625 ++struct xz_dec_bcj { 1.626 ++ /* Type of the BCJ filter being used */ 1.627 ++ enum { 1.628 ++ BCJ_X86 = 4, /* x86 or x86-64 */ 1.629 ++ BCJ_POWERPC = 5, /* Big endian only */ 1.630 ++ BCJ_IA64 = 6, /* Big or little endian */ 1.631 ++ BCJ_ARM = 7, /* Little endian only */ 1.632 ++ BCJ_ARMTHUMB = 8, /* Little endian only */ 1.633 ++ BCJ_SPARC = 9 /* Big or little endian */ 1.634 ++ } type; 1.635 ++ 1.636 ++ /* 1.637 ++ * Return value of the next filter in the chain. We need to preserve 1.638 ++ * this information across calls, because we must not call the next 1.639 ++ * filter anymore once it has returned XZ_STREAM_END. 1.640 ++ */ 1.641 ++ enum xz_ret ret; 1.642 ++ 1.643 ++ /* True if we are operating in single-call mode. */ 1.644 ++ bool single_call; 1.645 ++ 1.646 ++ /* 1.647 ++ * Absolute position relative to the beginning of the uncompressed 1.648 ++ * data (in a single .xz Block). We care only about the lowest 32 1.649 ++ * bits so this doesn't need to be uint64_t even with big files. 1.650 ++ */ 1.651 ++ uint32_t pos; 1.652 ++ 1.653 ++ /* x86 filter state */ 1.654 ++ uint32_t x86_prev_mask; 1.655 ++ 1.656 ++ /* Temporary space to hold the variables from struct xz_buf */ 1.657 ++ uint8_t *out; 1.658 ++ size_t out_pos; 1.659 ++ size_t out_size; 1.660 ++ 1.661 ++ struct { 1.662 ++ /* Amount of already filtered data in the beginning of buf */ 1.663 ++ size_t filtered; 1.664 ++ 1.665 ++ /* Total amount of data currently stored in buf */ 1.666 ++ size_t size; 1.667 ++ 1.668 ++ /* 1.669 ++ * Buffer to hold a mix of filtered and unfiltered data. This 1.670 ++ * needs to be big enough to hold Alignment + 2 * Look-ahead: 1.671 ++ * 1.672 ++ * Type Alignment Look-ahead 1.673 ++ * x86 1 4 1.674 ++ * PowerPC 4 0 1.675 ++ * IA-64 16 0 1.676 ++ * ARM 4 0 1.677 ++ * ARM-Thumb 2 2 1.678 ++ * SPARC 4 0 1.679 ++ */ 1.680 ++ uint8_t buf[16]; 1.681 ++ } temp; 1.682 ++}; 1.683 ++ 1.684 ++#ifdef XZ_DEC_X86 1.685 ++/* 1.686 ++ * This is used to test the most significant byte of a memory address 1.687 ++ * in an x86 instruction. 1.688 ++ */ 1.689 ++static inline int bcj_x86_test_msbyte(uint8_t b) 1.690 ++{ 1.691 ++ return b == 0x00 || b == 0xFF; 1.692 ++} 1.693 ++ 1.694 ++static size_t bcj_x86(struct xz_dec_bcj *s, uint8_t *buf, size_t size) 1.695 ++{ 1.696 ++ static const bool mask_to_allowed_status[8] 1.697 ++ = { true, true, true, false, true, false, false, false }; 1.698 ++ 1.699 ++ static const uint8_t mask_to_bit_num[8] = { 0, 1, 2, 2, 3, 3, 3, 3 }; 1.700 ++ 1.701 ++ size_t i; 1.702 ++ size_t prev_pos = (size_t)-1; 1.703 ++ uint32_t prev_mask = s->x86_prev_mask; 1.704 ++ uint32_t src; 1.705 ++ uint32_t dest; 1.706 ++ uint32_t j; 1.707 ++ uint8_t b; 1.708 ++ 1.709 ++ if (size <= 4) 1.710 ++ return 0; 1.711 ++ 1.712 ++ size -= 4; 1.713 ++ for (i = 0; i < size; ++i) { 1.714 ++ if ((buf[i] & 0xFE) != 0xE8) 1.715 ++ continue; 1.716 ++ 1.717 ++ prev_pos = i - prev_pos; 1.718 ++ if (prev_pos > 3) { 1.719 ++ prev_mask = 0; 1.720 ++ } else { 1.721 ++ prev_mask = (prev_mask << (prev_pos - 1)) & 7; 1.722 ++ if (prev_mask != 0) { 1.723 ++ b = buf[i + 4 - mask_to_bit_num[prev_mask]]; 1.724 ++ if (!mask_to_allowed_status[prev_mask] 1.725 ++ || bcj_x86_test_msbyte(b)) { 1.726 ++ prev_pos = i; 1.727 ++ prev_mask = (prev_mask << 1) | 1; 1.728 ++ continue; 1.729 ++ } 1.730 ++ } 1.731 ++ } 1.732 ++ 1.733 ++ prev_pos = i; 1.734 ++ 1.735 ++ if (bcj_x86_test_msbyte(buf[i + 4])) { 1.736 ++ src = get_unaligned_le32(buf + i + 1); 1.737 ++ while (true) { 1.738 ++ dest = src - (s->pos + (uint32_t)i + 5); 1.739 ++ if (prev_mask == 0) 1.740 ++ break; 1.741 ++ 1.742 ++ j = mask_to_bit_num[prev_mask] * 8; 1.743 ++ b = (uint8_t)(dest >> (24 - j)); 1.744 ++ if (!bcj_x86_test_msbyte(b)) 1.745 ++ break; 1.746 ++ 1.747 ++ src = dest ^ (((uint32_t)1 << (32 - j)) - 1); 1.748 ++ } 1.749 ++ 1.750 ++ dest &= 0x01FFFFFF; 1.751 ++ dest |= (uint32_t)0 - (dest & 0x01000000); 1.752 ++ put_unaligned_le32(dest, buf + i + 1); 1.753 ++ i += 4; 1.754 ++ } else { 1.755 ++ prev_mask = (prev_mask << 1) | 1; 1.756 ++ } 1.757 ++ } 1.758 ++ 1.759 ++ prev_pos = i - prev_pos; 1.760 ++ s->x86_prev_mask = prev_pos > 3 ? 0 : prev_mask << (prev_pos - 1); 1.761 ++ return i; 1.762 ++} 1.763 ++#endif 1.764 ++ 1.765 ++#ifdef XZ_DEC_POWERPC 1.766 ++static size_t bcj_powerpc(struct xz_dec_bcj *s, uint8_t *buf, size_t size) 1.767 ++{ 1.768 ++ size_t i; 1.769 ++ uint32_t instr; 1.770 ++ 1.771 ++ for (i = 0; i + 4 <= size; i += 4) { 1.772 ++ instr = get_unaligned_be32(buf + i); 1.773 ++ if ((instr & 0xFC000003) == 0x48000001) { 1.774 ++ instr &= 0x03FFFFFC; 1.775 ++ instr -= s->pos + (uint32_t)i; 1.776 ++ instr &= 0x03FFFFFC; 1.777 ++ instr |= 0x48000001; 1.778 ++ put_unaligned_be32(instr, buf + i); 1.779 ++ } 1.780 ++ } 1.781 ++ 1.782 ++ return i; 1.783 ++} 1.784 ++#endif 1.785 ++ 1.786 ++#ifdef XZ_DEC_IA64 1.787 ++static size_t bcj_ia64(struct xz_dec_bcj *s, uint8_t *buf, size_t size) 1.788 ++{ 1.789 ++ static const uint8_t branch_table[32] = { 1.790 ++ 0, 0, 0, 0, 0, 0, 0, 0, 1.791 ++ 0, 0, 0, 0, 0, 0, 0, 0, 1.792 ++ 4, 4, 6, 6, 0, 0, 7, 7, 1.793 ++ 4, 4, 0, 0, 4, 4, 0, 0 1.794 ++ }; 1.795 ++ 1.796 ++ /* 1.797 ++ * The local variables take a little bit stack space, but it's less 1.798 ++ * than what LZMA2 decoder takes, so it doesn't make sense to reduce 1.799 ++ * stack usage here without doing that for the LZMA2 decoder too. 1.800 ++ */ 1.801 ++ 1.802 ++ /* Loop counters */ 1.803 ++ size_t i; 1.804 ++ size_t j; 1.805 ++ 1.806 ++ /* Instruction slot (0, 1, or 2) in the 128-bit instruction word */ 1.807 ++ uint32_t slot; 1.808 ++ 1.809 ++ /* Bitwise offset of the instruction indicated by slot */ 1.810 ++ uint32_t bit_pos; 1.811 ++ 1.812 ++ /* bit_pos split into byte and bit parts */ 1.813 ++ uint32_t byte_pos; 1.814 ++ uint32_t bit_res; 1.815 ++ 1.816 ++ /* Address part of an instruction */ 1.817 ++ uint32_t addr; 1.818 ++ 1.819 ++ /* Mask used to detect which instructions to convert */ 1.820 ++ uint32_t mask; 1.821 ++ 1.822 ++ /* 41-bit instruction stored somewhere in the lowest 48 bits */ 1.823 ++ uint64_t instr; 1.824 ++ 1.825 ++ /* Instruction normalized with bit_res for easier manipulation */ 1.826 ++ uint64_t norm; 1.827 ++ 1.828 ++ for (i = 0; i + 16 <= size; i += 16) { 1.829 ++ mask = branch_table[buf[i] & 0x1F]; 1.830 ++ for (slot = 0, bit_pos = 5; slot < 3; ++slot, bit_pos += 41) { 1.831 ++ if (((mask >> slot) & 1) == 0) 1.832 ++ continue; 1.833 ++ 1.834 ++ byte_pos = bit_pos >> 3; 1.835 ++ bit_res = bit_pos & 7; 1.836 ++ instr = 0; 1.837 ++ for (j = 0; j < 6; ++j) 1.838 ++ instr |= (uint64_t)(buf[i + j + byte_pos]) 1.839 ++ << (8 * j); 1.840 ++ 1.841 ++ norm = instr >> bit_res; 1.842 ++ 1.843 ++ if (((norm >> 37) & 0x0F) == 0x05 1.844 ++ && ((norm >> 9) & 0x07) == 0) { 1.845 ++ addr = (norm >> 13) & 0x0FFFFF; 1.846 ++ addr |= ((uint32_t)(norm >> 36) & 1) << 20; 1.847 ++ addr <<= 4; 1.848 ++ addr -= s->pos + (uint32_t)i; 1.849 ++ addr >>= 4; 1.850 ++ 1.851 ++ norm &= ~((uint64_t)0x8FFFFF << 13); 1.852 ++ norm |= (uint64_t)(addr & 0x0FFFFF) << 13; 1.853 ++ norm |= (uint64_t)(addr & 0x100000) 1.854 ++ << (36 - 20); 1.855 ++ 1.856 ++ instr &= (1 << bit_res) - 1; 1.857 ++ instr |= norm << bit_res; 1.858 ++ 1.859 ++ for (j = 0; j < 6; j++) 1.860 ++ buf[i + j + byte_pos] 1.861 ++ = (uint8_t)(instr >> (8 * j)); 1.862 ++ } 1.863 ++ } 1.864 ++ } 1.865 ++ 1.866 ++ return i; 1.867 ++} 1.868 ++#endif 1.869 ++ 1.870 ++#ifdef XZ_DEC_ARM 1.871 ++static size_t bcj_arm(struct xz_dec_bcj *s, uint8_t *buf, size_t size) 1.872 ++{ 1.873 ++ size_t i; 1.874 ++ uint32_t addr; 1.875 ++ 1.876 ++ for (i = 0; i + 4 <= size; i += 4) { 1.877 ++ if (buf[i + 3] == 0xEB) { 1.878 ++ addr = (uint32_t)buf[i] | ((uint32_t)buf[i + 1] << 8) 1.879 ++ | ((uint32_t)buf[i + 2] << 16); 1.880 ++ addr <<= 2; 1.881 ++ addr -= s->pos + (uint32_t)i + 8; 1.882 ++ addr >>= 2; 1.883 ++ buf[i] = (uint8_t)addr; 1.884 ++ buf[i + 1] = (uint8_t)(addr >> 8); 1.885 ++ buf[i + 2] = (uint8_t)(addr >> 16); 1.886 ++ } 1.887 ++ } 1.888 ++ 1.889 ++ return i; 1.890 ++} 1.891 ++#endif 1.892 ++ 1.893 ++#ifdef XZ_DEC_ARMTHUMB 1.894 ++static size_t bcj_armthumb(struct xz_dec_bcj *s, uint8_t *buf, size_t size) 1.895 ++{ 1.896 ++ size_t i; 1.897 ++ uint32_t addr; 1.898 ++ 1.899 ++ for (i = 0; i + 4 <= size; i += 2) { 1.900 ++ if ((buf[i + 1] & 0xF8) == 0xF0 1.901 ++ && (buf[i + 3] & 0xF8) == 0xF8) { 1.902 ++ addr = (((uint32_t)buf[i + 1] & 0x07) << 19) 1.903 ++ | ((uint32_t)buf[i] << 11) 1.904 ++ | (((uint32_t)buf[i + 3] & 0x07) << 8) 1.905 ++ | (uint32_t)buf[i + 2]; 1.906 ++ addr <<= 1; 1.907 ++ addr -= s->pos + (uint32_t)i + 4; 1.908 ++ addr >>= 1; 1.909 ++ buf[i + 1] = (uint8_t)(0xF0 | ((addr >> 19) & 0x07)); 1.910 ++ buf[i] = (uint8_t)(addr >> 11); 1.911 ++ buf[i + 3] = (uint8_t)(0xF8 | ((addr >> 8) & 0x07)); 1.912 ++ buf[i + 2] = (uint8_t)addr; 1.913 ++ i += 2; 1.914 ++ } 1.915 ++ } 1.916 ++ 1.917 ++ return i; 1.918 ++} 1.919 ++#endif 1.920 ++ 1.921 ++#ifdef XZ_DEC_SPARC 1.922 ++static size_t bcj_sparc(struct xz_dec_bcj *s, uint8_t *buf, size_t size) 1.923 ++{ 1.924 ++ size_t i; 1.925 ++ uint32_t instr; 1.926 ++ 1.927 ++ for (i = 0; i + 4 <= size; i += 4) { 1.928 ++ instr = get_unaligned_be32(buf + i); 1.929 ++ if ((instr >> 22) == 0x100 || (instr >> 22) == 0x1FF) { 1.930 ++ instr <<= 2; 1.931 ++ instr -= s->pos + (uint32_t)i; 1.932 ++ instr >>= 2; 1.933 ++ instr = ((uint32_t)0x40000000 - (instr & 0x400000)) 1.934 ++ | 0x40000000 | (instr & 0x3FFFFF); 1.935 ++ put_unaligned_be32(instr, buf + i); 1.936 ++ } 1.937 ++ } 1.938 ++ 1.939 ++ return i; 1.940 ++} 1.941 ++#endif 1.942 ++ 1.943 ++/* 1.944 ++ * Apply the selected BCJ filter. Update *pos and s->pos to match the amount 1.945 ++ * of data that got filtered. 1.946 ++ * 1.947 ++ * NOTE: This is implemented as a switch statement to avoid using function 1.948 ++ * pointers, which could be problematic in the kernel boot code, which must 1.949 ++ * avoid pointers to static data (at least on x86). 1.950 ++ */ 1.951 ++static void bcj_apply(struct xz_dec_bcj *s, 1.952 ++ uint8_t *buf, size_t *pos, size_t size) 1.953 ++{ 1.954 ++ size_t filtered; 1.955 ++ 1.956 ++ buf += *pos; 1.957 ++ size -= *pos; 1.958 ++ 1.959 ++ switch (s->type) { 1.960 ++#ifdef XZ_DEC_X86 1.961 ++ case BCJ_X86: 1.962 ++ filtered = bcj_x86(s, buf, size); 1.963 ++ break; 1.964 ++#endif 1.965 ++#ifdef XZ_DEC_POWERPC 1.966 ++ case BCJ_POWERPC: 1.967 ++ filtered = bcj_powerpc(s, buf, size); 1.968 ++ break; 1.969 ++#endif 1.970 ++#ifdef XZ_DEC_IA64 1.971 ++ case BCJ_IA64: 1.972 ++ filtered = bcj_ia64(s, buf, size); 1.973 ++ break; 1.974 ++#endif 1.975 ++#ifdef XZ_DEC_ARM 1.976 ++ case BCJ_ARM: 1.977 ++ filtered = bcj_arm(s, buf, size); 1.978 ++ break; 1.979 ++#endif 1.980 ++#ifdef XZ_DEC_ARMTHUMB 1.981 ++ case BCJ_ARMTHUMB: 1.982 ++ filtered = bcj_armthumb(s, buf, size); 1.983 ++ break; 1.984 ++#endif 1.985 ++#ifdef XZ_DEC_SPARC 1.986 ++ case BCJ_SPARC: 1.987 ++ filtered = bcj_sparc(s, buf, size); 1.988 ++ break; 1.989 ++#endif 1.990 ++ default: 1.991 ++ /* Never reached but silence compiler warnings. */ 1.992 ++ filtered = 0; 1.993 ++ break; 1.994 ++ } 1.995 ++ 1.996 ++ *pos += filtered; 1.997 ++ s->pos += filtered; 1.998 ++} 1.999 ++ 1.1000 ++/* 1.1001 ++ * Flush pending filtered data from temp to the output buffer. 1.1002 ++ * Move the remaining mixture of possibly filtered and unfiltered 1.1003 ++ * data to the beginning of temp. 1.1004 ++ */ 1.1005 ++static void bcj_flush(struct xz_dec_bcj *s, struct xz_buf *b) 1.1006 ++{ 1.1007 ++ size_t copy_size; 1.1008 ++ 1.1009 ++ copy_size = min_t(size_t, s->temp.filtered, b->out_size - b->out_pos); 1.1010 ++ memcpy(b->out + b->out_pos, s->temp.buf, copy_size); 1.1011 ++ b->out_pos += copy_size; 1.1012 ++ 1.1013 ++ s->temp.filtered -= copy_size; 1.1014 ++ s->temp.size -= copy_size; 1.1015 ++ memmove(s->temp.buf, s->temp.buf + copy_size, s->temp.size); 1.1016 ++} 1.1017 ++ 1.1018 ++/* 1.1019 ++ * The BCJ filter functions are primitive in sense that they process the 1.1020 ++ * data in chunks of 1-16 bytes. To hide this issue, this function does 1.1021 ++ * some buffering. 1.1022 ++ */ 1.1023 ++XZ_EXTERN enum xz_ret xz_dec_bcj_run(struct xz_dec_bcj *s, 1.1024 ++ struct xz_dec_lzma2 *lzma2, 1.1025 ++ struct xz_buf *b) 1.1026 ++{ 1.1027 ++ size_t out_start; 1.1028 ++ 1.1029 ++ /* 1.1030 ++ * Flush pending already filtered data to the output buffer. Return 1.1031 ++ * immediatelly if we couldn't flush everything, or if the next 1.1032 ++ * filter in the chain had already returned XZ_STREAM_END. 1.1033 ++ */ 1.1034 ++ if (s->temp.filtered > 0) { 1.1035 ++ bcj_flush(s, b); 1.1036 ++ if (s->temp.filtered > 0) 1.1037 ++ return XZ_OK; 1.1038 ++ 1.1039 ++ if (s->ret == XZ_STREAM_END) 1.1040 ++ return XZ_STREAM_END; 1.1041 ++ } 1.1042 ++ 1.1043 ++ /* 1.1044 ++ * If we have more output space than what is currently pending in 1.1045 ++ * temp, copy the unfiltered data from temp to the output buffer 1.1046 ++ * and try to fill the output buffer by decoding more data from the 1.1047 ++ * next filter in the chain. Apply the BCJ filter on the new data 1.1048 ++ * in the output buffer. If everything cannot be filtered, copy it 1.1049 ++ * to temp and rewind the output buffer position accordingly. 1.1050 ++ */ 1.1051 ++ if (s->temp.size < b->out_size - b->out_pos) { 1.1052 ++ out_start = b->out_pos; 1.1053 ++ memcpy(b->out + b->out_pos, s->temp.buf, s->temp.size); 1.1054 ++ b->out_pos += s->temp.size; 1.1055 ++ 1.1056 ++ s->ret = xz_dec_lzma2_run(lzma2, b); 1.1057 ++ if (s->ret != XZ_STREAM_END 1.1058 ++ && (s->ret != XZ_OK || s->single_call)) 1.1059 ++ return s->ret; 1.1060 ++ 1.1061 ++ bcj_apply(s, b->out, &out_start, b->out_pos); 1.1062 ++ 1.1063 ++ /* 1.1064 ++ * As an exception, if the next filter returned XZ_STREAM_END, 1.1065 ++ * we can do that too, since the last few bytes that remain 1.1066 ++ * unfiltered are meant to remain unfiltered. 1.1067 ++ */ 1.1068 ++ if (s->ret == XZ_STREAM_END) 1.1069 ++ return XZ_STREAM_END; 1.1070 ++ 1.1071 ++ s->temp.size = b->out_pos - out_start; 1.1072 ++ b->out_pos -= s->temp.size; 1.1073 ++ memcpy(s->temp.buf, b->out + b->out_pos, s->temp.size); 1.1074 ++ } 1.1075 ++ 1.1076 ++ /* 1.1077 ++ * If we have unfiltered data in temp, try to fill by decoding more 1.1078 ++ * data from the next filter. Apply the BCJ filter on temp. Then we 1.1079 ++ * hopefully can fill the actual output buffer by copying filtered 1.1080 ++ * data from temp. A mix of filtered and unfiltered data may be left 1.1081 ++ * in temp; it will be taken care on the next call to this function. 1.1082 ++ */ 1.1083 ++ if (s->temp.size > 0) { 1.1084 ++ /* Make b->out{,_pos,_size} temporarily point to s->temp. */ 1.1085 ++ s->out = b->out; 1.1086 ++ s->out_pos = b->out_pos; 1.1087 ++ s->out_size = b->out_size; 1.1088 ++ b->out = s->temp.buf; 1.1089 ++ b->out_pos = s->temp.size; 1.1090 ++ b->out_size = sizeof(s->temp.buf); 1.1091 ++ 1.1092 ++ s->ret = xz_dec_lzma2_run(lzma2, b); 1.1093 ++ 1.1094 ++ s->temp.size = b->out_pos; 1.1095 ++ b->out = s->out; 1.1096 ++ b->out_pos = s->out_pos; 1.1097 ++ b->out_size = s->out_size; 1.1098 ++ 1.1099 ++ if (s->ret != XZ_OK && s->ret != XZ_STREAM_END) 1.1100 ++ return s->ret; 1.1101 ++ 1.1102 ++ bcj_apply(s, s->temp.buf, &s->temp.filtered, s->temp.size); 1.1103 ++ 1.1104 ++ /* 1.1105 ++ * If the next filter returned XZ_STREAM_END, we mark that 1.1106 ++ * everything is filtered, since the last unfiltered bytes 1.1107 ++ * of the stream are meant to be left as is. 1.1108 ++ */ 1.1109 ++ if (s->ret == XZ_STREAM_END) 1.1110 ++ s->temp.filtered = s->temp.size; 1.1111 ++ 1.1112 ++ bcj_flush(s, b); 1.1113 ++ if (s->temp.filtered > 0) 1.1114 ++ return XZ_OK; 1.1115 ++ } 1.1116 ++ 1.1117 ++ return s->ret; 1.1118 ++} 1.1119 ++ 1.1120 ++XZ_EXTERN struct xz_dec_bcj *xz_dec_bcj_create(bool single_call) 1.1121 ++{ 1.1122 ++ struct xz_dec_bcj *s = kmalloc(sizeof(*s), GFP_KERNEL); 1.1123 ++ if (s != NULL) 1.1124 ++ s->single_call = single_call; 1.1125 ++ 1.1126 ++ return s; 1.1127 ++} 1.1128 ++ 1.1129 ++XZ_EXTERN enum xz_ret xz_dec_bcj_reset(struct xz_dec_bcj *s, uint8_t id) 1.1130 ++{ 1.1131 ++ switch (id) { 1.1132 ++#ifdef XZ_DEC_X86 1.1133 ++ case BCJ_X86: 1.1134 ++#endif 1.1135 ++#ifdef XZ_DEC_POWERPC 1.1136 ++ case BCJ_POWERPC: 1.1137 ++#endif 1.1138 ++#ifdef XZ_DEC_IA64 1.1139 ++ case BCJ_IA64: 1.1140 ++#endif 1.1141 ++#ifdef XZ_DEC_ARM 1.1142 ++ case BCJ_ARM: 1.1143 ++#endif 1.1144 ++#ifdef XZ_DEC_ARMTHUMB 1.1145 ++ case BCJ_ARMTHUMB: 1.1146 ++#endif 1.1147 ++#ifdef XZ_DEC_SPARC 1.1148 ++ case BCJ_SPARC: 1.1149 ++#endif 1.1150 ++ break; 1.1151 ++ 1.1152 ++ default: 1.1153 ++ /* Unsupported Filter ID */ 1.1154 ++ return XZ_OPTIONS_ERROR; 1.1155 ++ } 1.1156 ++ 1.1157 ++ s->type = id; 1.1158 ++ s->ret = XZ_OK; 1.1159 ++ s->pos = 0; 1.1160 ++ s->x86_prev_mask = 0; 1.1161 ++ s->temp.filtered = 0; 1.1162 ++ s->temp.size = 0; 1.1163 ++ 1.1164 ++ return XZ_OK; 1.1165 ++} 1.1166 ++ 1.1167 ++#endif 1.1168 +diff --git a/lib/xz/xz_dec_lzma2.c b/lib/xz/xz_dec_lzma2.c 1.1169 +new file mode 100644 1.1170 +index 0000000..ea5fa4f 1.1171 +--- /dev/null 1.1172 ++++ b/lib/xz/xz_dec_lzma2.c 1.1173 +@@ -0,0 +1,1171 @@ 1.1174 ++/* 1.1175 ++ * LZMA2 decoder 1.1176 ++ * 1.1177 ++ * Authors: Lasse Collin <lasse.collin@tukaani.org> 1.1178 ++ * Igor Pavlov <http://7-zip.org/> 1.1179 ++ * 1.1180 ++ * This file has been put into the public domain. 1.1181 ++ * You can do whatever you want with this file. 1.1182 ++ */ 1.1183 ++ 1.1184 ++#include "xz_private.h" 1.1185 ++#include "xz_lzma2.h" 1.1186 ++ 1.1187 ++/* 1.1188 ++ * Range decoder initialization eats the first five bytes of each LZMA chunk. 1.1189 ++ */ 1.1190 ++#define RC_INIT_BYTES 5 1.1191 ++ 1.1192 ++/* 1.1193 ++ * Minimum number of usable input buffer to safely decode one LZMA symbol. 1.1194 ++ * The worst case is that we decode 22 bits using probabilities and 26 1.1195 ++ * direct bits. This may decode at maximum of 20 bytes of input. However, 1.1196 ++ * lzma_main() does an extra normalization before returning, thus we 1.1197 ++ * need to put 21 here. 1.1198 ++ */ 1.1199 ++#define LZMA_IN_REQUIRED 21 1.1200 ++ 1.1201 ++/* 1.1202 ++ * Dictionary (history buffer) 1.1203 ++ * 1.1204 ++ * These are always true: 1.1205 ++ * start <= pos <= full <= end 1.1206 ++ * pos <= limit <= end 1.1207 ++ * 1.1208 ++ * In multi-call mode, also these are true: 1.1209 ++ * end == size 1.1210 ++ * size <= size_max 1.1211 ++ * allocated <= size 1.1212 ++ * 1.1213 ++ * Most of these variables are size_t to support single-call mode, 1.1214 ++ * in which the dictionary variables address the actual output 1.1215 ++ * buffer directly. 1.1216 ++ */ 1.1217 ++struct dictionary { 1.1218 ++ /* Beginning of the history buffer */ 1.1219 ++ uint8_t *buf; 1.1220 ++ 1.1221 ++ /* Old position in buf (before decoding more data) */ 1.1222 ++ size_t start; 1.1223 ++ 1.1224 ++ /* Position in buf */ 1.1225 ++ size_t pos; 1.1226 ++ 1.1227 ++ /* 1.1228 ++ * How full dictionary is. This is used to detect corrupt input that 1.1229 ++ * would read beyond the beginning of the uncompressed stream. 1.1230 ++ */ 1.1231 ++ size_t full; 1.1232 ++ 1.1233 ++ /* Write limit; we don't write to buf[limit] or later bytes. */ 1.1234 ++ size_t limit; 1.1235 ++ 1.1236 ++ /* 1.1237 ++ * End of the dictionary buffer. In multi-call mode, this is 1.1238 ++ * the same as the dictionary size. In single-call mode, this 1.1239 ++ * indicates the size of the output buffer. 1.1240 ++ */ 1.1241 ++ size_t end; 1.1242 ++ 1.1243 ++ /* 1.1244 ++ * Size of the dictionary as specified in Block Header. This is used 1.1245 ++ * together with "full" to detect corrupt input that would make us 1.1246 ++ * read beyond the beginning of the uncompressed stream. 1.1247 ++ */ 1.1248 ++ uint32_t size; 1.1249 ++ 1.1250 ++ /* 1.1251 ++ * Maximum allowed dictionary size in multi-call mode. 1.1252 ++ * This is ignored in single-call mode. 1.1253 ++ */ 1.1254 ++ uint32_t size_max; 1.1255 ++ 1.1256 ++ /* 1.1257 ++ * Amount of memory currently allocated for the dictionary. 1.1258 ++ * This is used only with XZ_DYNALLOC. (With XZ_PREALLOC, 1.1259 ++ * size_max is always the same as the allocated size.) 1.1260 ++ */ 1.1261 ++ uint32_t allocated; 1.1262 ++ 1.1263 ++ /* Operation mode */ 1.1264 ++ enum xz_mode mode; 1.1265 ++}; 1.1266 ++ 1.1267 ++/* Range decoder */ 1.1268 ++struct rc_dec { 1.1269 ++ uint32_t range; 1.1270 ++ uint32_t code; 1.1271 ++ 1.1272 ++ /* 1.1273 ++ * Number of initializing bytes remaining to be read 1.1274 ++ * by rc_read_init(). 1.1275 ++ */ 1.1276 ++ uint32_t init_bytes_left; 1.1277 ++ 1.1278 ++ /* 1.1279 ++ * Buffer from which we read our input. It can be either 1.1280 ++ * temp.buf or the caller-provided input buffer. 1.1281 ++ */ 1.1282 ++ const uint8_t *in; 1.1283 ++ size_t in_pos; 1.1284 ++ size_t in_limit; 1.1285 ++}; 1.1286 ++ 1.1287 ++/* Probabilities for a length decoder. */ 1.1288 ++struct lzma_len_dec { 1.1289 ++ /* Probability of match length being at least 10 */ 1.1290 ++ uint16_t choice; 1.1291 ++ 1.1292 ++ /* Probability of match length being at least 18 */ 1.1293 ++ uint16_t choice2; 1.1294 ++ 1.1295 ++ /* Probabilities for match lengths 2-9 */ 1.1296 ++ uint16_t low[POS_STATES_MAX][LEN_LOW_SYMBOLS]; 1.1297 ++ 1.1298 ++ /* Probabilities for match lengths 10-17 */ 1.1299 ++ uint16_t mid[POS_STATES_MAX][LEN_MID_SYMBOLS]; 1.1300 ++ 1.1301 ++ /* Probabilities for match lengths 18-273 */ 1.1302 ++ uint16_t high[LEN_HIGH_SYMBOLS]; 1.1303 ++}; 1.1304 ++ 1.1305 ++struct lzma_dec { 1.1306 ++ /* Distances of latest four matches */ 1.1307 ++ uint32_t rep0; 1.1308 ++ uint32_t rep1; 1.1309 ++ uint32_t rep2; 1.1310 ++ uint32_t rep3; 1.1311 ++ 1.1312 ++ /* Types of the most recently seen LZMA symbols */ 1.1313 ++ enum lzma_state state; 1.1314 ++ 1.1315 ++ /* 1.1316 ++ * Length of a match. This is updated so that dict_repeat can 1.1317 ++ * be called again to finish repeating the whole match. 1.1318 ++ */ 1.1319 ++ uint32_t len; 1.1320 ++ 1.1321 ++ /* 1.1322 ++ * LZMA properties or related bit masks (number of literal 1.1323 ++ * context bits, a mask dervied from the number of literal 1.1324 ++ * position bits, and a mask dervied from the number 1.1325 ++ * position bits) 1.1326 ++ */ 1.1327 ++ uint32_t lc; 1.1328 ++ uint32_t literal_pos_mask; /* (1 << lp) - 1 */ 1.1329 ++ uint32_t pos_mask; /* (1 << pb) - 1 */ 1.1330 ++ 1.1331 ++ /* If 1, it's a match. Otherwise it's a single 8-bit literal. */ 1.1332 ++ uint16_t is_match[STATES][POS_STATES_MAX]; 1.1333 ++ 1.1334 ++ /* If 1, it's a repeated match. The distance is one of rep0 .. rep3. */ 1.1335 ++ uint16_t is_rep[STATES]; 1.1336 ++ 1.1337 ++ /* 1.1338 ++ * If 0, distance of a repeated match is rep0. 1.1339 ++ * Otherwise check is_rep1. 1.1340 ++ */ 1.1341 ++ uint16_t is_rep0[STATES]; 1.1342 ++ 1.1343 ++ /* 1.1344 ++ * If 0, distance of a repeated match is rep1. 1.1345 ++ * Otherwise check is_rep2. 1.1346 ++ */ 1.1347 ++ uint16_t is_rep1[STATES]; 1.1348 ++ 1.1349 ++ /* If 0, distance of a repeated match is rep2. Otherwise it is rep3. */ 1.1350 ++ uint16_t is_rep2[STATES]; 1.1351 ++ 1.1352 ++ /* 1.1353 ++ * If 1, the repeated match has length of one byte. Otherwise 1.1354 ++ * the length is decoded from rep_len_decoder. 1.1355 ++ */ 1.1356 ++ uint16_t is_rep0_long[STATES][POS_STATES_MAX]; 1.1357 ++ 1.1358 ++ /* 1.1359 ++ * Probability tree for the highest two bits of the match 1.1360 ++ * distance. There is a separate probability tree for match 1.1361 ++ * lengths of 2 (i.e. MATCH_LEN_MIN), 3, 4, and [5, 273]. 1.1362 ++ */ 1.1363 ++ uint16_t dist_slot[DIST_STATES][DIST_SLOTS]; 1.1364 ++ 1.1365 ++ /* 1.1366 ++ * Probility trees for additional bits for match distance 1.1367 ++ * when the distance is in the range [4, 127]. 1.1368 ++ */ 1.1369 ++ uint16_t dist_special[FULL_DISTANCES - DIST_MODEL_END]; 1.1370 ++ 1.1371 ++ /* 1.1372 ++ * Probability tree for the lowest four bits of a match 1.1373 ++ * distance that is equal to or greater than 128. 1.1374 ++ */ 1.1375 ++ uint16_t dist_align[ALIGN_SIZE]; 1.1376 ++ 1.1377 ++ /* Length of a normal match */ 1.1378 ++ struct lzma_len_dec match_len_dec; 1.1379 ++ 1.1380 ++ /* Length of a repeated match */ 1.1381 ++ struct lzma_len_dec rep_len_dec; 1.1382 ++ 1.1383 ++ /* Probabilities of literals */ 1.1384 ++ uint16_t literal[LITERAL_CODERS_MAX][LITERAL_CODER_SIZE]; 1.1385 ++}; 1.1386 ++ 1.1387 ++struct lzma2_dec { 1.1388 ++ /* Position in xz_dec_lzma2_run(). */ 1.1389 ++ enum lzma2_seq { 1.1390 ++ SEQ_CONTROL, 1.1391 ++ SEQ_UNCOMPRESSED_1, 1.1392 ++ SEQ_UNCOMPRESSED_2, 1.1393 ++ SEQ_COMPRESSED_0, 1.1394 ++ SEQ_COMPRESSED_1, 1.1395 ++ SEQ_PROPERTIES, 1.1396 ++ SEQ_LZMA_PREPARE, 1.1397 ++ SEQ_LZMA_RUN, 1.1398 ++ SEQ_COPY 1.1399 ++ } sequence; 1.1400 ++ 1.1401 ++ /* Next position after decoding the compressed size of the chunk. */ 1.1402 ++ enum lzma2_seq next_sequence; 1.1403 ++ 1.1404 ++ /* Uncompressed size of LZMA chunk (2 MiB at maximum) */ 1.1405 ++ uint32_t uncompressed; 1.1406 ++ 1.1407 ++ /* 1.1408 ++ * Compressed size of LZMA chunk or compressed/uncompressed 1.1409 ++ * size of uncompressed chunk (64 KiB at maximum) 1.1410 ++ */ 1.1411 ++ uint32_t compressed; 1.1412 ++ 1.1413 ++ /* 1.1414 ++ * True if dictionary reset is needed. This is false before 1.1415 ++ * the first chunk (LZMA or uncompressed). 1.1416 ++ */ 1.1417 ++ bool need_dict_reset; 1.1418 ++ 1.1419 ++ /* 1.1420 ++ * True if new LZMA properties are needed. This is false 1.1421 ++ * before the first LZMA chunk. 1.1422 ++ */ 1.1423 ++ bool need_props; 1.1424 ++}; 1.1425 ++ 1.1426 ++struct xz_dec_lzma2 { 1.1427 ++ /* 1.1428 ++ * The order below is important on x86 to reduce code size and 1.1429 ++ * it shouldn't hurt on other platforms. Everything up to and 1.1430 ++ * including lzma.pos_mask are in the first 128 bytes on x86-32, 1.1431 ++ * which allows using smaller instructions to access those 1.1432 ++ * variables. On x86-64, fewer variables fit into the first 128 1.1433 ++ * bytes, but this is still the best order without sacrificing 1.1434 ++ * the readability by splitting the structures. 1.1435 ++ */ 1.1436 ++ struct rc_dec rc; 1.1437 ++ struct dictionary dict; 1.1438 ++ struct lzma2_dec lzma2; 1.1439 ++ struct lzma_dec lzma; 1.1440 ++ 1.1441 ++ /* 1.1442 ++ * Temporary buffer which holds small number of input bytes between 1.1443 ++ * decoder calls. See lzma2_lzma() for details. 1.1444 ++ */ 1.1445 ++ struct { 1.1446 ++ uint32_t size; 1.1447 ++ uint8_t buf[3 * LZMA_IN_REQUIRED]; 1.1448 ++ } temp; 1.1449 ++}; 1.1450 ++ 1.1451 ++/************** 1.1452 ++ * Dictionary * 1.1453 ++ **************/ 1.1454 ++ 1.1455 ++/* 1.1456 ++ * Reset the dictionary state. When in single-call mode, set up the beginning 1.1457 ++ * of the dictionary to point to the actual output buffer. 1.1458 ++ */ 1.1459 ++static void dict_reset(struct dictionary *dict, struct xz_buf *b) 1.1460 ++{ 1.1461 ++ if (DEC_IS_SINGLE(dict->mode)) { 1.1462 ++ dict->buf = b->out + b->out_pos; 1.1463 ++ dict->end = b->out_size - b->out_pos; 1.1464 ++ } 1.1465 ++ 1.1466 ++ dict->start = 0; 1.1467 ++ dict->pos = 0; 1.1468 ++ dict->limit = 0; 1.1469 ++ dict->full = 0; 1.1470 ++} 1.1471 ++ 1.1472 ++/* Set dictionary write limit */ 1.1473 ++static void dict_limit(struct dictionary *dict, size_t out_max) 1.1474 ++{ 1.1475 ++ if (dict->end - dict->pos <= out_max) 1.1476 ++ dict->limit = dict->end; 1.1477 ++ else 1.1478 ++ dict->limit = dict->pos + out_max; 1.1479 ++} 1.1480 ++ 1.1481 ++/* Return true if at least one byte can be written into the dictionary. */ 1.1482 ++static inline bool dict_has_space(const struct dictionary *dict) 1.1483 ++{ 1.1484 ++ return dict->pos < dict->limit; 1.1485 ++} 1.1486 ++ 1.1487 ++/* 1.1488 ++ * Get a byte from the dictionary at the given distance. The distance is 1.1489 ++ * assumed to valid, or as a special case, zero when the dictionary is 1.1490 ++ * still empty. This special case is needed for single-call decoding to 1.1491 ++ * avoid writing a '\0' to the end of the destination buffer. 1.1492 ++ */ 1.1493 ++static inline uint32_t dict_get(const struct dictionary *dict, uint32_t dist) 1.1494 ++{ 1.1495 ++ size_t offset = dict->pos - dist - 1; 1.1496 ++ 1.1497 ++ if (dist >= dict->pos) 1.1498 ++ offset += dict->end; 1.1499 ++ 1.1500 ++ return dict->full > 0 ? dict->buf[offset] : 0; 1.1501 ++} 1.1502 ++ 1.1503 ++/* 1.1504 ++ * Put one byte into the dictionary. It is assumed that there is space for it. 1.1505 ++ */ 1.1506 ++static inline void dict_put(struct dictionary *dict, uint8_t byte) 1.1507 ++{ 1.1508 ++ dict->buf[dict->pos++] = byte; 1.1509 ++ 1.1510 ++ if (dict->full < dict->pos) 1.1511 ++ dict->full = dict->pos; 1.1512 ++} 1.1513 ++ 1.1514 ++/* 1.1515 ++ * Repeat given number of bytes from the given distance. If the distance is 1.1516 ++ * invalid, false is returned. On success, true is returned and *len is 1.1517 ++ * updated to indicate how many bytes were left to be repeated. 1.1518 ++ */ 1.1519 ++static bool dict_repeat(struct dictionary *dict, uint32_t *len, uint32_t dist) 1.1520 ++{ 1.1521 ++ size_t back; 1.1522 ++ uint32_t left; 1.1523 ++ 1.1524 ++ if (dist >= dict->full || dist >= dict->size) 1.1525 ++ return false; 1.1526 ++ 1.1527 ++ left = min_t(size_t, dict->limit - dict->pos, *len); 1.1528 ++ *len -= left; 1.1529 ++ 1.1530 ++ back = dict->pos - dist - 1; 1.1531 ++ if (dist >= dict->pos) 1.1532 ++ back += dict->end; 1.1533 ++ 1.1534 ++ do { 1.1535 ++ dict->buf[dict->pos++] = dict->buf[back++]; 1.1536 ++ if (back == dict->end) 1.1537 ++ back = 0; 1.1538 ++ } while (--left > 0); 1.1539 ++ 1.1540 ++ if (dict->full < dict->pos) 1.1541 ++ dict->full = dict->pos; 1.1542 ++ 1.1543 ++ return true; 1.1544 ++} 1.1545 ++ 1.1546 ++/* Copy uncompressed data as is from input to dictionary and output buffers. */ 1.1547 ++static void dict_uncompressed(struct dictionary *dict, struct xz_buf *b, 1.1548 ++ uint32_t *left) 1.1549 ++{ 1.1550 ++ size_t copy_size; 1.1551 ++ 1.1552 ++ while (*left > 0 && b->in_pos < b->in_size 1.1553 ++ && b->out_pos < b->out_size) { 1.1554 ++ copy_size = min(b->in_size - b->in_pos, 1.1555 ++ b->out_size - b->out_pos); 1.1556 ++ if (copy_size > dict->end - dict->pos) 1.1557 ++ copy_size = dict->end - dict->pos; 1.1558 ++ if (copy_size > *left) 1.1559 ++ copy_size = *left; 1.1560 ++ 1.1561 ++ *left -= copy_size; 1.1562 ++ 1.1563 ++ memcpy(dict->buf + dict->pos, b->in + b->in_pos, copy_size); 1.1564 ++ dict->pos += copy_size; 1.1565 ++ 1.1566 ++ if (dict->full < dict->pos) 1.1567 ++ dict->full = dict->pos; 1.1568 ++ 1.1569 ++ if (DEC_IS_MULTI(dict->mode)) { 1.1570 ++ if (dict->pos == dict->end) 1.1571 ++ dict->pos = 0; 1.1572 ++ 1.1573 ++ memcpy(b->out + b->out_pos, b->in + b->in_pos, 1.1574 ++ copy_size); 1.1575 ++ } 1.1576 ++ 1.1577 ++ dict->start = dict->pos; 1.1578 ++ 1.1579 ++ b->out_pos += copy_size; 1.1580 ++ b->in_pos += copy_size; 1.1581 ++ } 1.1582 ++} 1.1583 ++ 1.1584 ++/* 1.1585 ++ * Flush pending data from dictionary to b->out. It is assumed that there is 1.1586 ++ * enough space in b->out. This is guaranteed because caller uses dict_limit() 1.1587 ++ * before decoding data into the dictionary. 1.1588 ++ */ 1.1589 ++static uint32_t dict_flush(struct dictionary *dict, struct xz_buf *b) 1.1590 ++{ 1.1591 ++ size_t copy_size = dict->pos - dict->start; 1.1592 ++ 1.1593 ++ if (DEC_IS_MULTI(dict->mode)) { 1.1594 ++ if (dict->pos == dict->end) 1.1595 ++ dict->pos = 0; 1.1596 ++ 1.1597 ++ memcpy(b->out + b->out_pos, dict->buf + dict->start, 1.1598 ++ copy_size); 1.1599 ++ } 1.1600 ++ 1.1601 ++ dict->start = dict->pos; 1.1602 ++ b->out_pos += copy_size; 1.1603 ++ return copy_size; 1.1604 ++} 1.1605 ++ 1.1606 ++/***************** 1.1607 ++ * Range decoder * 1.1608 ++ *****************/ 1.1609 ++ 1.1610 ++/* Reset the range decoder. */ 1.1611 ++static void rc_reset(struct rc_dec *rc) 1.1612 ++{ 1.1613 ++ rc->range = (uint32_t)-1; 1.1614 ++ rc->code = 0; 1.1615 ++ rc->init_bytes_left = RC_INIT_BYTES; 1.1616 ++} 1.1617 ++ 1.1618 ++/* 1.1619 ++ * Read the first five initial bytes into rc->code if they haven't been 1.1620 ++ * read already. (Yes, the first byte gets completely ignored.) 1.1621 ++ */ 1.1622 ++static bool rc_read_init(struct rc_dec *rc, struct xz_buf *b) 1.1623 ++{ 1.1624 ++ while (rc->init_bytes_left > 0) { 1.1625 ++ if (b->in_pos == b->in_size) 1.1626 ++ return false; 1.1627 ++ 1.1628 ++ rc->code = (rc->code << 8) + b->in[b->in_pos++]; 1.1629 ++ --rc->init_bytes_left; 1.1630 ++ } 1.1631 ++ 1.1632 ++ return true; 1.1633 ++} 1.1634 ++ 1.1635 ++/* Return true if there may not be enough input for the next decoding loop. */ 1.1636 ++static inline bool rc_limit_exceeded(const struct rc_dec *rc) 1.1637 ++{ 1.1638 ++ return rc->in_pos > rc->in_limit; 1.1639 ++} 1.1640 ++ 1.1641 ++/* 1.1642 ++ * Return true if it is possible (from point of view of range decoder) that 1.1643 ++ * we have reached the end of the LZMA chunk. 1.1644 ++ */ 1.1645 ++static inline bool rc_is_finished(const struct rc_dec *rc) 1.1646 ++{ 1.1647 ++ return rc->code == 0; 1.1648 ++} 1.1649 ++ 1.1650 ++/* Read the next input byte if needed. */ 1.1651 ++static __always_inline void rc_normalize(struct rc_dec *rc) 1.1652 ++{ 1.1653 ++ if (rc->range < RC_TOP_VALUE) { 1.1654 ++ rc->range <<= RC_SHIFT_BITS; 1.1655 ++ rc->code = (rc->code << RC_SHIFT_BITS) + rc->in[rc->in_pos++]; 1.1656 ++ } 1.1657 ++} 1.1658 ++ 1.1659 ++/* 1.1660 ++ * Decode one bit. In some versions, this function has been splitted in three 1.1661 ++ * functions so that the compiler is supposed to be able to more easily avoid 1.1662 ++ * an extra branch. In this particular version of the LZMA decoder, this 1.1663 ++ * doesn't seem to be a good idea (tested with GCC 3.3.6, 3.4.6, and 4.3.3 1.1664 ++ * on x86). Using a non-splitted version results in nicer looking code too. 1.1665 ++ * 1.1666 ++ * NOTE: This must return an int. Do not make it return a bool or the speed 1.1667 ++ * of the code generated by GCC 3.x decreases 10-15 %. (GCC 4.3 doesn't care, 1.1668 ++ * and it generates 10-20 % faster code than GCC 3.x from this file anyway.) 1.1669 ++ */ 1.1670 ++static __always_inline int rc_bit(struct rc_dec *rc, uint16_t *prob) 1.1671 ++{ 1.1672 ++ uint32_t bound; 1.1673 ++ int bit; 1.1674 ++ 1.1675 ++ rc_normalize(rc); 1.1676 ++ bound = (rc->range >> RC_BIT_MODEL_TOTAL_BITS) * *prob; 1.1677 ++ if (rc->code < bound) { 1.1678 ++ rc->range = bound; 1.1679 ++ *prob += (RC_BIT_MODEL_TOTAL - *prob) >> RC_MOVE_BITS; 1.1680 ++ bit = 0; 1.1681 ++ } else { 1.1682 ++ rc->range -= bound; 1.1683 ++ rc->code -= bound; 1.1684 ++ *prob -= *prob >> RC_MOVE_BITS; 1.1685 ++ bit = 1; 1.1686 ++ } 1.1687 ++ 1.1688 ++ return bit; 1.1689 ++} 1.1690 ++ 1.1691 ++/* Decode a bittree starting from the most significant bit. */ 1.1692 ++static __always_inline uint32_t rc_bittree(struct rc_dec *rc, 1.1693 ++ uint16_t *probs, uint32_t limit) 1.1694 ++{ 1.1695 ++ uint32_t symbol = 1; 1.1696 ++ 1.1697 ++ do { 1.1698 ++ if (rc_bit(rc, &probs[symbol])) 1.1699 ++ symbol = (symbol << 1) + 1; 1.1700 ++ else 1.1701 ++ symbol <<= 1; 1.1702 ++ } while (symbol < limit); 1.1703 ++ 1.1704 ++ return symbol; 1.1705 ++} 1.1706 ++ 1.1707 ++/* Decode a bittree starting from the least significant bit. */ 1.1708 ++static __always_inline void rc_bittree_reverse(struct rc_dec *rc, 1.1709 ++ uint16_t *probs, 1.1710 ++ uint32_t *dest, uint32_t limit) 1.1711 ++{ 1.1712 ++ uint32_t symbol = 1; 1.1713 ++ uint32_t i = 0; 1.1714 ++ 1.1715 ++ do { 1.1716 ++ if (rc_bit(rc, &probs[symbol])) { 1.1717 ++ symbol = (symbol << 1) + 1; 1.1718 ++ *dest += 1 << i; 1.1719 ++ } else { 1.1720 ++ symbol <<= 1; 1.1721 ++ } 1.1722 ++ } while (++i < limit); 1.1723 ++} 1.1724 ++ 1.1725 ++/* Decode direct bits (fixed fifty-fifty probability) */ 1.1726 ++static inline void rc_direct(struct rc_dec *rc, uint32_t *dest, uint32_t limit) 1.1727 ++{ 1.1728 ++ uint32_t mask; 1.1729 ++ 1.1730 ++ do { 1.1731 ++ rc_normalize(rc); 1.1732 ++ rc->range >>= 1; 1.1733 ++ rc->code -= rc->range; 1.1734 ++ mask = (uint32_t)0 - (rc->code >> 31); 1.1735 ++ rc->code += rc->range & mask; 1.1736 ++ *dest = (*dest << 1) + (mask + 1); 1.1737 ++ } while (--limit > 0); 1.1738 ++} 1.1739 ++ 1.1740 ++/******** 1.1741 ++ * LZMA * 1.1742 ++ ********/ 1.1743 ++ 1.1744 ++/* Get pointer to literal coder probability array. */ 1.1745 ++static uint16_t *lzma_literal_probs(struct xz_dec_lzma2 *s) 1.1746 ++{ 1.1747 ++ uint32_t prev_byte = dict_get(&s->dict, 0); 1.1748 ++ uint32_t low = prev_byte >> (8 - s->lzma.lc); 1.1749 ++ uint32_t high = (s->dict.pos & s->lzma.literal_pos_mask) << s->lzma.lc; 1.1750 ++ return s->lzma.literal[low + high]; 1.1751 ++} 1.1752 ++ 1.1753 ++/* Decode a literal (one 8-bit byte) */ 1.1754 ++static void lzma_literal(struct xz_dec_lzma2 *s) 1.1755 ++{ 1.1756 ++ uint16_t *probs; 1.1757 ++ uint32_t symbol; 1.1758 ++ uint32_t match_byte; 1.1759 ++ uint32_t match_bit; 1.1760 ++ uint32_t offset; 1.1761 ++ uint32_t i; 1.1762 ++ 1.1763 ++ probs = lzma_literal_probs(s); 1.1764 ++ 1.1765 ++ if (lzma_state_is_literal(s->lzma.state)) { 1.1766 ++ symbol = rc_bittree(&s->rc, probs, 0x100); 1.1767 ++ } else { 1.1768 ++ symbol = 1; 1.1769 ++ match_byte = dict_get(&s->dict, s->lzma.rep0) << 1; 1.1770 ++ offset = 0x100; 1.1771 ++ 1.1772 ++ do { 1.1773 ++ match_bit = match_byte & offset; 1.1774 ++ match_byte <<= 1; 1.1775 ++ i = offset + match_bit + symbol; 1.1776 ++ 1.1777 ++ if (rc_bit(&s->rc, &probs[i])) { 1.1778 ++ symbol = (symbol << 1) + 1; 1.1779 ++ offset &= match_bit; 1.1780 ++ } else { 1.1781 ++ symbol <<= 1; 1.1782 ++ offset &= ~match_bit; 1.1783 ++ } 1.1784 ++ } while (symbol < 0x100); 1.1785 ++ } 1.1786 ++ 1.1787 ++ dict_put(&s->dict, (uint8_t)symbol); 1.1788 ++ lzma_state_literal(&s->lzma.state); 1.1789 ++} 1.1790 ++ 1.1791 ++/* Decode the length of the match into s->lzma.len. */ 1.1792 ++static void lzma_len(struct xz_dec_lzma2 *s, struct lzma_len_dec *l, 1.1793 ++ uint32_t pos_state) 1.1794 ++{ 1.1795 ++ uint16_t *probs; 1.1796 ++ uint32_t limit; 1.1797 ++ 1.1798 ++ if (!rc_bit(&s->rc, &l->choice)) { 1.1799 ++ probs = l->low[pos_state]; 1.1800 ++ limit = LEN_LOW_SYMBOLS; 1.1801 ++ s->lzma.len = MATCH_LEN_MIN; 1.1802 ++ } else { 1.1803 ++ if (!rc_bit(&s->rc, &l->choice2)) { 1.1804 ++ probs = l->mid[pos_state]; 1.1805 ++ limit = LEN_MID_SYMBOLS; 1.1806 ++ s->lzma.len = MATCH_LEN_MIN + LEN_LOW_SYMBOLS; 1.1807 ++ } else { 1.1808 ++ probs = l->high; 1.1809 ++ limit = LEN_HIGH_SYMBOLS; 1.1810 ++ s->lzma.len = MATCH_LEN_MIN + LEN_LOW_SYMBOLS 1.1811 ++ + LEN_MID_SYMBOLS; 1.1812 ++ } 1.1813 ++ } 1.1814 ++ 1.1815 ++ s->lzma.len += rc_bittree(&s->rc, probs, limit) - limit; 1.1816 ++} 1.1817 ++ 1.1818 ++/* Decode a match. The distance will be stored in s->lzma.rep0. */ 1.1819 ++static void lzma_match(struct xz_dec_lzma2 *s, uint32_t pos_state) 1.1820 ++{ 1.1821 ++ uint16_t *probs; 1.1822 ++ uint32_t dist_slot; 1.1823 ++ uint32_t limit; 1.1824 ++ 1.1825 ++ lzma_state_match(&s->lzma.state); 1.1826 ++ 1.1827 ++ s->lzma.rep3 = s->lzma.rep2; 1.1828 ++ s->lzma.rep2 = s->lzma.rep1; 1.1829 ++ s->lzma.rep1 = s->lzma.rep0; 1.1830 ++ 1.1831 ++ lzma_len(s, &s->lzma.match_len_dec, pos_state); 1.1832 ++ 1.1833 ++ probs = s->lzma.dist_slot[lzma_get_dist_state(s->lzma.len)]; 1.1834 ++ dist_slot = rc_bittree(&s->rc, probs, DIST_SLOTS) - DIST_SLOTS; 1.1835 ++ 1.1836 ++ if (dist_slot < DIST_MODEL_START) { 1.1837 ++ s->lzma.rep0 = dist_slot; 1.1838 ++ } else { 1.1839 ++ limit = (dist_slot >> 1) - 1; 1.1840 ++ s->lzma.rep0 = 2 + (dist_slot & 1); 1.1841 ++ 1.1842 ++ if (dist_slot < DIST_MODEL_END) { 1.1843 ++ s->lzma.rep0 <<= limit; 1.1844 ++ probs = s->lzma.dist_special + s->lzma.rep0 1.1845 ++ - dist_slot - 1; 1.1846 ++ rc_bittree_reverse(&s->rc, probs, 1.1847 ++ &s->lzma.rep0, limit); 1.1848 ++ } else { 1.1849 ++ rc_direct(&s->rc, &s->lzma.rep0, limit - ALIGN_BITS); 1.1850 ++ s->lzma.rep0 <<= ALIGN_BITS; 1.1851 ++ rc_bittree_reverse(&s->rc, s->lzma.dist_align, 1.1852 ++ &s->lzma.rep0, ALIGN_BITS); 1.1853 ++ } 1.1854 ++ } 1.1855 ++} 1.1856 ++ 1.1857 ++/* 1.1858 ++ * Decode a repeated match. The distance is one of the four most recently 1.1859 ++ * seen matches. The distance will be stored in s->lzma.rep0. 1.1860 ++ */ 1.1861 ++static void lzma_rep_match(struct xz_dec_lzma2 *s, uint32_t pos_state) 1.1862 ++{ 1.1863 ++ uint32_t tmp; 1.1864 ++ 1.1865 ++ if (!rc_bit(&s->rc, &s->lzma.is_rep0[s->lzma.state])) { 1.1866 ++ if (!rc_bit(&s->rc, &s->lzma.is_rep0_long[ 1.1867 ++ s->lzma.state][pos_state])) { 1.1868 ++ lzma_state_short_rep(&s->lzma.state); 1.1869 ++ s->lzma.len = 1; 1.1870 ++ return; 1.1871 ++ } 1.1872 ++ } else { 1.1873 ++ if (!rc_bit(&s->rc, &s->lzma.is_rep1[s->lzma.state])) { 1.1874 ++ tmp = s->lzma.rep1; 1.1875 ++ } else { 1.1876 ++ if (!rc_bit(&s->rc, &s->lzma.is_rep2[s->lzma.state])) { 1.1877 ++ tmp = s->lzma.rep2; 1.1878 ++ } else { 1.1879 ++ tmp = s->lzma.rep3; 1.1880 ++ s->lzma.rep3 = s->lzma.rep2; 1.1881 ++ } 1.1882 ++ 1.1883 ++ s->lzma.rep2 = s->lzma.rep1; 1.1884 ++ } 1.1885 ++ 1.1886 ++ s->lzma.rep1 = s->lzma.rep0; 1.1887 ++ s->lzma.rep0 = tmp; 1.1888 ++ } 1.1889 ++ 1.1890 ++ lzma_state_long_rep(&s->lzma.state); 1.1891 ++ lzma_len(s, &s->lzma.rep_len_dec, pos_state); 1.1892 ++} 1.1893 ++ 1.1894 ++/* LZMA decoder core */ 1.1895 ++static bool lzma_main(struct xz_dec_lzma2 *s) 1.1896 ++{ 1.1897 ++ uint32_t pos_state; 1.1898 ++ 1.1899 ++ /* 1.1900 ++ * If the dictionary was reached during the previous call, try to 1.1901 ++ * finish the possibly pending repeat in the dictionary. 1.1902 ++ */ 1.1903 ++ if (dict_has_space(&s->dict) && s->lzma.len > 0) 1.1904 ++ dict_repeat(&s->dict, &s->lzma.len, s->lzma.rep0); 1.1905 ++ 1.1906 ++ /* 1.1907 ++ * Decode more LZMA symbols. One iteration may consume up to 1.1908 ++ * LZMA_IN_REQUIRED - 1 bytes. 1.1909 ++ */ 1.1910 ++ while (dict_has_space(&s->dict) && !rc_limit_exceeded(&s->rc)) { 1.1911 ++ pos_state = s->dict.pos & s->lzma.pos_mask; 1.1912 ++ 1.1913 ++ if (!rc_bit(&s->rc, &s->lzma.is_match[ 1.1914 ++ s->lzma.state][pos_state])) { 1.1915 ++ lzma_literal(s); 1.1916 ++ } else { 1.1917 ++ if (rc_bit(&s->rc, &s->lzma.is_rep[s->lzma.state])) 1.1918 ++ lzma_rep_match(s, pos_state); 1.1919 ++ else 1.1920 ++ lzma_match(s, pos_state); 1.1921 ++ 1.1922 ++ if (!dict_repeat(&s->dict, &s->lzma.len, s->lzma.rep0)) 1.1923 ++ return false; 1.1924 ++ } 1.1925 ++ } 1.1926 ++ 1.1927 ++ /* 1.1928 ++ * Having the range decoder always normalized when we are outside 1.1929 ++ * this function makes it easier to correctly handle end of the chunk. 1.1930 ++ */ 1.1931 ++ rc_normalize(&s->rc); 1.1932 ++ 1.1933 ++ return true; 1.1934 ++} 1.1935 ++ 1.1936 ++/* 1.1937 ++ * Reset the LZMA decoder and range decoder state. Dictionary is nore reset 1.1938 ++ * here, because LZMA state may be reset without resetting the dictionary. 1.1939 ++ */ 1.1940 ++static void lzma_reset(struct xz_dec_lzma2 *s) 1.1941 ++{ 1.1942 ++ uint16_t *probs; 1.1943 ++ size_t i; 1.1944 ++ 1.1945 ++ s->lzma.state = STATE_LIT_LIT; 1.1946 ++ s->lzma.rep0 = 0; 1.1947 ++ s->lzma.rep1 = 0; 1.1948 ++ s->lzma.rep2 = 0; 1.1949 ++ s->lzma.rep3 = 0; 1.1950 ++ 1.1951 ++ /* 1.1952 ++ * All probabilities are initialized to the same value. This hack 1.1953 ++ * makes the code smaller by avoiding a separate loop for each 1.1954 ++ * probability array. 1.1955 ++ * 1.1956 ++ * This could be optimized so that only that part of literal 1.1957 ++ * probabilities that are actually required. In the common case 1.1958 ++ * we would write 12 KiB less. 1.1959 ++ */ 1.1960 ++ probs = s->lzma.is_match[0]; 1.1961 ++ for (i = 0; i < PROBS_TOTAL; ++i) 1.1962 ++ probs[i] = RC_BIT_MODEL_TOTAL / 2; 1.1963 ++ 1.1964 ++ rc_reset(&s->rc); 1.1965 ++} 1.1966 ++ 1.1967 ++/* 1.1968 ++ * Decode and validate LZMA properties (lc/lp/pb) and calculate the bit masks 1.1969 ++ * from the decoded lp and pb values. On success, the LZMA decoder state is 1.1970 ++ * reset and true is returned. 1.1971 ++ */ 1.1972 ++static bool lzma_props(struct xz_dec_lzma2 *s, uint8_t props) 1.1973 ++{ 1.1974 ++ if (props > (4 * 5 + 4) * 9 + 8) 1.1975 ++ return false; 1.1976 ++ 1.1977 ++ s->lzma.pos_mask = 0; 1.1978 ++ while (props >= 9 * 5) { 1.1979 ++ props -= 9 * 5; 1.1980 ++ ++s->lzma.pos_mask; 1.1981 ++ } 1.1982 ++ 1.1983 ++ s->lzma.pos_mask = (1 << s->lzma.pos_mask) - 1; 1.1984 ++ 1.1985 ++ s->lzma.literal_pos_mask = 0; 1.1986 ++ while (props >= 9) { 1.1987 ++ props -= 9; 1.1988 ++ ++s->lzma.literal_pos_mask; 1.1989 ++ } 1.1990 ++ 1.1991 ++ s->lzma.lc = props; 1.1992 ++ 1.1993 ++ if (s->lzma.lc + s->lzma.literal_pos_mask > 4) 1.1994 ++ return false; 1.1995 ++ 1.1996 ++ s->lzma.literal_pos_mask = (1 << s->lzma.literal_pos_mask) - 1; 1.1997 ++ 1.1998 ++ lzma_reset(s); 1.1999 ++ 1.2000 ++ return true; 1.2001 ++} 1.2002 ++ 1.2003 ++/********* 1.2004 ++ * LZMA2 * 1.2005 ++ *********/ 1.2006 ++ 1.2007 ++/* 1.2008 ++ * The LZMA decoder assumes that if the input limit (s->rc.in_limit) hasn't 1.2009 ++ * been exceeded, it is safe to read up to LZMA_IN_REQUIRED bytes. This 1.2010 ++ * wrapper function takes care of making the LZMA decoder's assumption safe. 1.2011 ++ * 1.2012 ++ * As long as there is plenty of input left to be decoded in the current LZMA 1.2013 ++ * chunk, we decode directly from the caller-supplied input buffer until 1.2014 ++ * there's LZMA_IN_REQUIRED bytes left. Those remaining bytes are copied into 1.2015 ++ * s->temp.buf, which (hopefully) gets filled on the next call to this 1.2016 ++ * function. We decode a few bytes from the temporary buffer so that we can 1.2017 ++ * continue decoding from the caller-supplied input buffer again. 1.2018 ++ */ 1.2019 ++static bool lzma2_lzma(struct xz_dec_lzma2 *s, struct xz_buf *b) 1.2020 ++{ 1.2021 ++ size_t in_avail; 1.2022 ++ uint32_t tmp; 1.2023 ++ 1.2024 ++ in_avail = b->in_size - b->in_pos; 1.2025 ++ if (s->temp.size > 0 || s->lzma2.compressed == 0) { 1.2026 ++ tmp = 2 * LZMA_IN_REQUIRED - s->temp.size; 1.2027 ++ if (tmp > s->lzma2.compressed - s->temp.size) 1.2028 ++ tmp = s->lzma2.compressed - s->temp.size; 1.2029 ++ if (tmp > in_avail) 1.2030 ++ tmp = in_avail; 1.2031 ++ 1.2032 ++ memcpy(s->temp.buf + s->temp.size, b->in + b->in_pos, tmp); 1.2033 ++ 1.2034 ++ if (s->temp.size + tmp == s->lzma2.compressed) { 1.2035 ++ memzero(s->temp.buf + s->temp.size + tmp, 1.2036 ++ sizeof(s->temp.buf) 1.2037 ++ - s->temp.size - tmp); 1.2038 ++ s->rc.in_limit = s->temp.size + tmp; 1.2039 ++ } else if (s->temp.size + tmp < LZMA_IN_REQUIRED) { 1.2040 ++ s->temp.size += tmp; 1.2041 ++ b->in_pos += tmp; 1.2042 ++ return true; 1.2043 ++ } else { 1.2044 ++ s->rc.in_limit = s->temp.size + tmp - LZMA_IN_REQUIRED; 1.2045 ++ } 1.2046 ++ 1.2047 ++ s->rc.in = s->temp.buf; 1.2048 ++ s->rc.in_pos = 0; 1.2049 ++ 1.2050 ++ if (!lzma_main(s) || s->rc.in_pos > s->temp.size + tmp) 1.2051 ++ return false; 1.2052 ++ 1.2053 ++ s->lzma2.compressed -= s->rc.in_pos; 1.2054 ++ 1.2055 ++ if (s->rc.in_pos < s->temp.size) { 1.2056 ++ s->temp.size -= s->rc.in_pos; 1.2057 ++ memmove(s->temp.buf, s->temp.buf + s->rc.in_pos, 1.2058 ++ s->temp.size); 1.2059 ++ return true; 1.2060 ++ } 1.2061 ++ 1.2062 ++ b->in_pos += s->rc.in_pos - s->temp.size; 1.2063 ++ s->temp.size = 0; 1.2064 ++ } 1.2065 ++ 1.2066 ++ in_avail = b->in_size - b->in_pos; 1.2067 ++ if (in_avail >= LZMA_IN_REQUIRED) { 1.2068 ++ s->rc.in = b->in; 1.2069 ++ s->rc.in_pos = b->in_pos; 1.2070 ++ 1.2071 ++ if (in_avail >= s->lzma2.compressed + LZMA_IN_REQUIRED) 1.2072 ++ s->rc.in_limit = b->in_pos + s->lzma2.compressed; 1.2073 ++ else 1.2074 ++ s->rc.in_limit = b->in_size - LZMA_IN_REQUIRED; 1.2075 ++ 1.2076 ++ if (!lzma_main(s)) 1.2077 ++ return false; 1.2078 ++ 1.2079 ++ in_avail = s->rc.in_pos - b->in_pos; 1.2080 ++ if (in_avail > s->lzma2.compressed) 1.2081 ++ return false; 1.2082 ++ 1.2083 ++ s->lzma2.compressed -= in_avail; 1.2084 ++ b->in_pos = s->rc.in_pos; 1.2085 ++ } 1.2086 ++ 1.2087 ++ in_avail = b->in_size - b->in_pos; 1.2088 ++ if (in_avail < LZMA_IN_REQUIRED) { 1.2089 ++ if (in_avail > s->lzma2.compressed) 1.2090 ++ in_avail = s->lzma2.compressed; 1.2091 ++ 1.2092 ++ memcpy(s->temp.buf, b->in + b->in_pos, in_avail); 1.2093 ++ s->temp.size = in_avail; 1.2094 ++ b->in_pos += in_avail; 1.2095 ++ } 1.2096 ++ 1.2097 ++ return true; 1.2098 ++} 1.2099 ++ 1.2100 ++/* 1.2101 ++ * Take care of the LZMA2 control layer, and forward the job of actual LZMA 1.2102 ++ * decoding or copying of uncompressed chunks to other functions. 1.2103 ++ */ 1.2104 ++XZ_EXTERN enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s, 1.2105 ++ struct xz_buf *b) 1.2106 ++{ 1.2107 ++ uint32_t tmp; 1.2108 ++ 1.2109 ++ while (b->in_pos < b->in_size || s->lzma2.sequence == SEQ_LZMA_RUN) { 1.2110 ++ switch (s->lzma2.sequence) { 1.2111 ++ case SEQ_CONTROL: 1.2112 ++ /* 1.2113 ++ * LZMA2 control byte 1.2114 ++ * 1.2115 ++ * Exact values: 1.2116 ++ * 0x00 End marker 1.2117 ++ * 0x01 Dictionary reset followed by 1.2118 ++ * an uncompressed chunk 1.2119 ++ * 0x02 Uncompressed chunk (no dictionary reset) 1.2120 ++ * 1.2121 ++ * Highest three bits (s->control & 0xE0): 1.2122 ++ * 0xE0 Dictionary reset, new properties and state 1.2123 ++ * reset, followed by LZMA compressed chunk 1.2124 ++ * 0xC0 New properties and state reset, followed 1.2125 ++ * by LZMA compressed chunk (no dictionary 1.2126 ++ * reset) 1.2127 ++ * 0xA0 State reset using old properties, 1.2128 ++ * followed by LZMA compressed chunk (no 1.2129 ++ * dictionary reset) 1.2130 ++ * 0x80 LZMA chunk (no dictionary or state reset) 1.2131 ++ * 1.2132 ++ * For LZMA compressed chunks, the lowest five bits 1.2133 ++ * (s->control & 1F) are the highest bits of the 1.2134 ++ * uncompressed size (bits 16-20). 1.2135 ++ * 1.2136 ++ * A new LZMA2 stream must begin with a dictionary 1.2137 ++ * reset. The first LZMA chunk must set new 1.2138 ++ * properties and reset the LZMA state. 1.2139 ++ * 1.2140 ++ * Values that don't match anything described above 1.2141 ++ * are invalid and we return XZ_DATA_ERROR. 1.2142 ++ */ 1.2143 ++ tmp = b->in[b->in_pos++]; 1.2144 ++ 1.2145 ++ if (tmp >= 0xE0 || tmp == 0x01) { 1.2146 ++ s->lzma2.need_props = true; 1.2147 ++ s->lzma2.need_dict_reset = false; 1.2148 ++ dict_reset(&s->dict, b); 1.2149 ++ } else if (s->lzma2.need_dict_reset) { 1.2150 ++ return XZ_DATA_ERROR; 1.2151 ++ } 1.2152 ++ 1.2153 ++ if (tmp >= 0x80) { 1.2154 ++ s->lzma2.uncompressed = (tmp & 0x1F) << 16; 1.2155 ++ s->lzma2.sequence = SEQ_UNCOMPRESSED_1; 1.2156 ++ 1.2157 ++ if (tmp >= 0xC0) { 1.2158 ++ /* 1.2159 ++ * When there are new properties, 1.2160 ++ * state reset is done at 1.2161 ++ * SEQ_PROPERTIES. 1.2162 ++ */ 1.2163 ++ s->lzma2.need_props = false; 1.2164 ++ s->lzma2.next_sequence 1.2165 ++ = SEQ_PROPERTIES; 1.2166 ++ 1.2167 ++ } else if (s->lzma2.need_props) { 1.2168 ++ return XZ_DATA_ERROR; 1.2169 ++ 1.2170 ++ } else { 1.2171 ++ s->lzma2.next_sequence 1.2172 ++ = SEQ_LZMA_PREPARE; 1.2173 ++ if (tmp >= 0xA0) 1.2174 ++ lzma_reset(s); 1.2175 ++ } 1.2176 ++ } else { 1.2177 ++ if (tmp == 0x00) 1.2178 ++ return XZ_STREAM_END; 1.2179 ++ 1.2180 ++ if (tmp > 0x02) 1.2181 ++ return XZ_DATA_ERROR; 1.2182 ++ 1.2183 ++ s->lzma2.sequence = SEQ_COMPRESSED_0; 1.2184 ++ s->lzma2.next_sequence = SEQ_COPY; 1.2185 ++ } 1.2186 ++ 1.2187 ++ break; 1.2188 ++ 1.2189 ++ case SEQ_UNCOMPRESSED_1: 1.2190 ++ s->lzma2.uncompressed 1.2191 ++ += (uint32_t)b->in[b->in_pos++] << 8; 1.2192 ++ s->lzma2.sequence = SEQ_UNCOMPRESSED_2; 1.2193 ++ break; 1.2194 ++ 1.2195 ++ case SEQ_UNCOMPRESSED_2: 1.2196 ++ s->lzma2.uncompressed 1.2197 ++ += (uint32_t)b->in[b->in_pos++] + 1; 1.2198 ++ s->lzma2.sequence = SEQ_COMPRESSED_0; 1.2199 ++ break; 1.2200 ++ 1.2201 ++ case SEQ_COMPRESSED_0: 1.2202 ++ s->lzma2.compressed 1.2203 ++ = (uint32_t)b->in[b->in_pos++] << 8; 1.2204 ++ s->lzma2.sequence = SEQ_COMPRESSED_1; 1.2205 ++ break; 1.2206 ++ 1.2207 ++ case SEQ_COMPRESSED_1: 1.2208 ++ s->lzma2.compressed 1.2209 ++ += (uint32_t)b->in[b->in_pos++] + 1; 1.2210 ++ s->lzma2.sequence = s->lzma2.next_sequence; 1.2211 ++ break; 1.2212 ++ 1.2213 ++ case SEQ_PROPERTIES: 1.2214 ++ if (!lzma_props(s, b->in[b->in_pos++])) 1.2215 ++ return XZ_DATA_ERROR; 1.2216 ++ 1.2217 ++ s->lzma2.sequence = SEQ_LZMA_PREPARE; 1.2218 ++ 1.2219 ++ case SEQ_LZMA_PREPARE: 1.2220 ++ if (s->lzma2.compressed < RC_INIT_BYTES) 1.2221 ++ return XZ_DATA_ERROR; 1.2222 ++ 1.2223 ++ if (!rc_read_init(&s->rc, b)) 1.2224 ++ return XZ_OK; 1.2225 ++ 1.2226 ++ s->lzma2.compressed -= RC_INIT_BYTES; 1.2227 ++ s->lzma2.sequence = SEQ_LZMA_RUN; 1.2228 ++ 1.2229 ++ case SEQ_LZMA_RUN: 1.2230 ++ /* 1.2231 ++ * Set dictionary limit to indicate how much we want 1.2232 ++ * to be encoded at maximum. Decode new data into the 1.2233 ++ * dictionary. Flush the new data from dictionary to 1.2234 ++ * b->out. Check if we finished decoding this chunk. 1.2235 ++ * In case the dictionary got full but we didn't fill 1.2236 ++ * the output buffer yet, we may run this loop 1.2237 ++ * multiple times without changing s->lzma2.sequence. 1.2238 ++ */ 1.2239 ++ dict_limit(&s->dict, min_t(size_t, 1.2240 ++ b->out_size - b->out_pos, 1.2241 ++ s->lzma2.uncompressed)); 1.2242 ++ if (!lzma2_lzma(s, b)) 1.2243 ++ return XZ_DATA_ERROR; 1.2244 ++ 1.2245 ++ s->lzma2.uncompressed -= dict_flush(&s->dict, b); 1.2246 ++ 1.2247 ++ if (s->lzma2.uncompressed == 0) { 1.2248 ++ if (s->lzma2.compressed > 0 || s->lzma.len > 0 1.2249 ++ || !rc_is_finished(&s->rc)) 1.2250 ++ return XZ_DATA_ERROR; 1.2251 ++ 1.2252 ++ rc_reset(&s->rc); 1.2253 ++ s->lzma2.sequence = SEQ_CONTROL; 1.2254 ++ 1.2255 ++ } else if (b->out_pos == b->out_size 1.2256 ++ || (b->in_pos == b->in_size 1.2257 ++ && s->temp.size 1.2258 ++ < s->lzma2.compressed)) { 1.2259 ++ return XZ_OK; 1.2260 ++ } 1.2261 ++ 1.2262 ++ break; 1.2263 ++ 1.2264 ++ case SEQ_COPY: 1.2265 ++ dict_uncompressed(&s->dict, b, &s->lzma2.compressed); 1.2266 ++ if (s->lzma2.compressed > 0) 1.2267 ++ return XZ_OK; 1.2268 ++ 1.2269 ++ s->lzma2.sequence = SEQ_CONTROL; 1.2270 ++ break; 1.2271 ++ } 1.2272 ++ } 1.2273 ++ 1.2274 ++ return XZ_OK; 1.2275 ++} 1.2276 ++ 1.2277 ++XZ_EXTERN struct xz_dec_lzma2 *xz_dec_lzma2_create(enum xz_mode mode, 1.2278 ++ uint32_t dict_max) 1.2279 ++{ 1.2280 ++ struct xz_dec_lzma2 *s = kmalloc(sizeof(*s), GFP_KERNEL); 1.2281 ++ if (s == NULL) 1.2282 ++ return NULL; 1.2283 ++ 1.2284 ++ s->dict.mode = mode; 1.2285 ++ s->dict.size_max = dict_max; 1.2286 ++ 1.2287 ++ if (DEC_IS_PREALLOC(mode)) { 1.2288 ++ s->dict.buf = vmalloc(dict_max); 1.2289 ++ if (s->dict.buf == NULL) { 1.2290 ++ kfree(s); 1.2291 ++ return NULL; 1.2292 ++ } 1.2293 ++ } else if (DEC_IS_DYNALLOC(mode)) { 1.2294 ++ s->dict.buf = NULL; 1.2295 ++ s->dict.allocated = 0; 1.2296 ++ } 1.2297 ++ 1.2298 ++ return s; 1.2299 ++} 1.2300 ++ 1.2301 ++XZ_EXTERN enum xz_ret xz_dec_lzma2_reset(struct xz_dec_lzma2 *s, uint8_t props) 1.2302 ++{ 1.2303 ++ /* This limits dictionary size to 3 GiB to keep parsing simpler. */ 1.2304 ++ if (props > 39) 1.2305 ++ return XZ_OPTIONS_ERROR; 1.2306 ++ 1.2307 ++ s->dict.size = 2 + (props & 1); 1.2308 ++ s->dict.size <<= (props >> 1) + 11; 1.2309 ++ 1.2310 ++ if (DEC_IS_MULTI(s->dict.mode)) { 1.2311 ++ if (s->dict.size > s->dict.size_max) 1.2312 ++ return XZ_MEMLIMIT_ERROR; 1.2313 ++ 1.2314 ++ s->dict.end = s->dict.size; 1.2315 ++ 1.2316 ++ if (DEC_IS_DYNALLOC(s->dict.mode)) { 1.2317 ++ if (s->dict.allocated < s->dict.size) { 1.2318 ++ vfree(s->dict.buf); 1.2319 ++ s->dict.buf = vmalloc(s->dict.size); 1.2320 ++ if (s->dict.buf == NULL) { 1.2321 ++ s->dict.allocated = 0; 1.2322 ++ return XZ_MEM_ERROR; 1.2323 ++ } 1.2324 ++ } 1.2325 ++ } 1.2326 ++ } 1.2327 ++ 1.2328 ++ s->lzma.len = 0; 1.2329 ++ 1.2330 ++ s->lzma2.sequence = SEQ_CONTROL; 1.2331 ++ s->lzma2.need_dict_reset = true; 1.2332 ++ 1.2333 ++ s->temp.size = 0; 1.2334 ++ 1.2335 ++ return XZ_OK; 1.2336 ++} 1.2337 ++ 1.2338 ++XZ_EXTERN void xz_dec_lzma2_end(struct xz_dec_lzma2 *s) 1.2339 ++{ 1.2340 ++ if (DEC_IS_MULTI(s->dict.mode)) 1.2341 ++ vfree(s->dict.buf); 1.2342 ++ 1.2343 ++ kfree(s); 1.2344 ++} 1.2345 +diff --git a/lib/xz/xz_dec_stream.c b/lib/xz/xz_dec_stream.c 1.2346 +new file mode 100644 1.2347 +index 0000000..ac809b1 1.2348 +--- /dev/null 1.2349 ++++ b/lib/xz/xz_dec_stream.c 1.2350 +@@ -0,0 +1,821 @@ 1.2351 ++/* 1.2352 ++ * .xz Stream decoder 1.2353 ++ * 1.2354 ++ * Author: Lasse Collin <lasse.collin@tukaani.org> 1.2355 ++ * 1.2356 ++ * This file has been put into the public domain. 1.2357 ++ * You can do whatever you want with this file. 1.2358 ++ */ 1.2359 ++ 1.2360 ++#include "xz_private.h" 1.2361 ++#include "xz_stream.h" 1.2362 ++ 1.2363 ++/* Hash used to validate the Index field */ 1.2364 ++struct xz_dec_hash { 1.2365 ++ vli_type unpadded; 1.2366 ++ vli_type uncompressed; 1.2367 ++ uint32_t crc32; 1.2368 ++}; 1.2369 ++ 1.2370 ++struct xz_dec { 1.2371 ++ /* Position in dec_main() */ 1.2372 ++ enum { 1.2373 ++ SEQ_STREAM_HEADER, 1.2374 ++ SEQ_BLOCK_START, 1.2375 ++ SEQ_BLOCK_HEADER, 1.2376 ++ SEQ_BLOCK_UNCOMPRESS, 1.2377 ++ SEQ_BLOCK_PADDING, 1.2378 ++ SEQ_BLOCK_CHECK, 1.2379 ++ SEQ_INDEX, 1.2380 ++ SEQ_INDEX_PADDING, 1.2381 ++ SEQ_INDEX_CRC32, 1.2382 ++ SEQ_STREAM_FOOTER 1.2383 ++ } sequence; 1.2384 ++ 1.2385 ++ /* Position in variable-length integers and Check fields */ 1.2386 ++ uint32_t pos; 1.2387 ++ 1.2388 ++ /* Variable-length integer decoded by dec_vli() */ 1.2389 ++ vli_type vli; 1.2390 ++ 1.2391 ++ /* Saved in_pos and out_pos */ 1.2392 ++ size_t in_start; 1.2393 ++ size_t out_start; 1.2394 ++ 1.2395 ++ /* CRC32 value in Block or Index */ 1.2396 ++ uint32_t crc32; 1.2397 ++ 1.2398 ++ /* Type of the integrity check calculated from uncompressed data */ 1.2399 ++ enum xz_check check_type; 1.2400 ++ 1.2401 ++ /* Operation mode */ 1.2402 ++ enum xz_mode mode; 1.2403 ++ 1.2404 ++ /* 1.2405 ++ * True if the next call to xz_dec_run() is allowed to return 1.2406 ++ * XZ_BUF_ERROR. 1.2407 ++ */ 1.2408 ++ bool allow_buf_error; 1.2409 ++ 1.2410 ++ /* Information stored in Block Header */ 1.2411 ++ struct { 1.2412 ++ /* 1.2413 ++ * Value stored in the Compressed Size field, or 1.2414 ++ * VLI_UNKNOWN if Compressed Size is not present. 1.2415 ++ */ 1.2416 ++ vli_type compressed; 1.2417 ++ 1.2418 ++ /* 1.2419 ++ * Value stored in the Uncompressed Size field, or 1.2420 ++ * VLI_UNKNOWN if Uncompressed Size is not present. 1.2421 ++ */ 1.2422 ++ vli_type uncompressed; 1.2423 ++ 1.2424 ++ /* Size of the Block Header field */ 1.2425 ++ uint32_t size; 1.2426 ++ } block_header; 1.2427 ++ 1.2428 ++ /* Information collected when decoding Blocks */ 1.2429 ++ struct { 1.2430 ++ /* Observed compressed size of the current Block */ 1.2431 ++ vli_type compressed; 1.2432 ++ 1.2433 ++ /* Observed uncompressed size of the current Block */ 1.2434 ++ vli_type uncompressed; 1.2435 ++ 1.2436 ++ /* Number of Blocks decoded so far */ 1.2437 ++ vli_type count; 1.2438 ++ 1.2439 ++ /* 1.2440 ++ * Hash calculated from the Block sizes. This is used to 1.2441 ++ * validate the Index field. 1.2442 ++ */ 1.2443 ++ struct xz_dec_hash hash; 1.2444 ++ } block; 1.2445 ++ 1.2446 ++ /* Variables needed when verifying the Index field */ 1.2447 ++ struct { 1.2448 ++ /* Position in dec_index() */ 1.2449 ++ enum { 1.2450 ++ SEQ_INDEX_COUNT, 1.2451 ++ SEQ_INDEX_UNPADDED, 1.2452 ++ SEQ_INDEX_UNCOMPRESSED 1.2453 ++ } sequence; 1.2454 ++ 1.2455 ++ /* Size of the Index in bytes */ 1.2456 ++ vli_type size; 1.2457 ++ 1.2458 ++ /* Number of Records (matches block.count in valid files) */ 1.2459 ++ vli_type count; 1.2460 ++ 1.2461 ++ /* 1.2462 ++ * Hash calculated from the Records (matches block.hash in 1.2463 ++ * valid files). 1.2464 ++ */ 1.2465 ++ struct xz_dec_hash hash; 1.2466 ++ } index; 1.2467 ++ 1.2468 ++ /* 1.2469 ++ * Temporary buffer needed to hold Stream Header, Block Header, 1.2470 ++ * and Stream Footer. The Block Header is the biggest (1 KiB) 1.2471 ++ * so we reserve space according to that. buf[] has to be aligned 1.2472 ++ * to a multiple of four bytes; the size_t variables before it 1.2473 ++ * should guarantee this. 1.2474 ++ */ 1.2475 ++ struct { 1.2476 ++ size_t pos; 1.2477 ++ size_t size; 1.2478 ++ uint8_t buf[1024]; 1.2479 ++ } temp; 1.2480 ++ 1.2481 ++ struct xz_dec_lzma2 *lzma2; 1.2482 ++ 1.2483 ++#ifdef XZ_DEC_BCJ 1.2484 ++ struct xz_dec_bcj *bcj; 1.2485 ++ bool bcj_active; 1.2486 ++#endif 1.2487 ++}; 1.2488 ++ 1.2489 ++#ifdef XZ_DEC_ANY_CHECK 1.2490 ++/* Sizes of the Check field with different Check IDs */ 1.2491 ++static const uint8_t check_sizes[16] = { 1.2492 ++ 0, 1.2493 ++ 4, 4, 4, 1.2494 ++ 8, 8, 8, 1.2495 ++ 16, 16, 16, 1.2496 ++ 32, 32, 32, 1.2497 ++ 64, 64, 64 1.2498 ++}; 1.2499 ++#endif 1.2500 ++ 1.2501 ++/* 1.2502 ++ * Fill s->temp by copying data starting from b->in[b->in_pos]. Caller 1.2503 ++ * must have set s->temp.pos to indicate how much data we are supposed 1.2504 ++ * to copy into s->temp.buf. Return true once s->temp.pos has reached 1.2505 ++ * s->temp.size. 1.2506 ++ */ 1.2507 ++static bool fill_temp(struct xz_dec *s, struct xz_buf *b) 1.2508 ++{ 1.2509 ++ size_t copy_size = min_t(size_t, 1.2510 ++ b->in_size - b->in_pos, s->temp.size - s->temp.pos); 1.2511 ++ 1.2512 ++ memcpy(s->temp.buf + s->temp.pos, b->in + b->in_pos, copy_size); 1.2513 ++ b->in_pos += copy_size; 1.2514 ++ s->temp.pos += copy_size; 1.2515 ++ 1.2516 ++ if (s->temp.pos == s->temp.size) { 1.2517 ++ s->temp.pos = 0; 1.2518 ++ return true; 1.2519 ++ } 1.2520 ++ 1.2521 ++ return false; 1.2522 ++} 1.2523 ++ 1.2524 ++/* Decode a variable-length integer (little-endian base-128 encoding) */ 1.2525 ++static enum xz_ret dec_vli(struct xz_dec *s, const uint8_t *in, 1.2526 ++ size_t *in_pos, size_t in_size) 1.2527 ++{ 1.2528 ++ uint8_t byte; 1.2529 ++ 1.2530 ++ if (s->pos == 0) 1.2531 ++ s->vli = 0; 1.2532 ++ 1.2533 ++ while (*in_pos < in_size) { 1.2534 ++ byte = in[*in_pos]; 1.2535 ++ ++*in_pos; 1.2536 ++ 1.2537 ++ s->vli |= (vli_type)(byte & 0x7F) << s->pos; 1.2538 ++ 1.2539 ++ if ((byte & 0x80) == 0) { 1.2540 ++ /* Don't allow non-minimal encodings. */ 1.2541 ++ if (byte == 0 && s->pos != 0) 1.2542 ++ return XZ_DATA_ERROR; 1.2543 ++ 1.2544 ++ s->pos = 0; 1.2545 ++ return XZ_STREAM_END; 1.2546 ++ } 1.2547 ++ 1.2548 ++ s->pos += 7; 1.2549 ++ if (s->pos == 7 * VLI_BYTES_MAX) 1.2550 ++ return XZ_DATA_ERROR; 1.2551 ++ } 1.2552 ++ 1.2553 ++ return XZ_OK; 1.2554 ++} 1.2555 ++ 1.2556 ++/* 1.2557 ++ * Decode the Compressed Data field from a Block. Update and validate 1.2558 ++ * the observed compressed and uncompressed sizes of the Block so that 1.2559 ++ * they don't exceed the values possibly stored in the Block Header 1.2560 ++ * (validation assumes that no integer overflow occurs, since vli_type 1.2561 ++ * is normally uint64_t). Update the CRC32 if presence of the CRC32 1.2562 ++ * field was indicated in Stream Header. 1.2563 ++ * 1.2564 ++ * Once the decoding is finished, validate that the observed sizes match 1.2565 ++ * the sizes possibly stored in the Block Header. Update the hash and 1.2566 ++ * Block count, which are later used to validate the Index field. 1.2567 ++ */ 1.2568 ++static enum xz_ret dec_block(struct xz_dec *s, struct xz_buf *b) 1.2569 ++{ 1.2570 ++ enum xz_ret ret; 1.2571 ++ 1.2572 ++ s->in_start = b->in_pos; 1.2573 ++ s->out_start = b->out_pos; 1.2574 ++ 1.2575 ++#ifdef XZ_DEC_BCJ 1.2576 ++ if (s->bcj_active) 1.2577 ++ ret = xz_dec_bcj_run(s->bcj, s->lzma2, b); 1.2578 ++ else 1.2579 ++#endif 1.2580 ++ ret = xz_dec_lzma2_run(s->lzma2, b); 1.2581 ++ 1.2582 ++ s->block.compressed += b->in_pos - s->in_start; 1.2583 ++ s->block.uncompressed += b->out_pos - s->out_start; 1.2584 ++ 1.2585 ++ /* 1.2586 ++ * There is no need to separately check for VLI_UNKNOWN, since 1.2587 ++ * the observed sizes are always smaller than VLI_UNKNOWN. 1.2588 ++ */ 1.2589 ++ if (s->block.compressed > s->block_header.compressed 1.2590 ++ || s->block.uncompressed 1.2591 ++ > s->block_header.uncompressed) 1.2592 ++ return XZ_DATA_ERROR; 1.2593 ++ 1.2594 ++ if (s->check_type == XZ_CHECK_CRC32) 1.2595 ++ s->crc32 = xz_crc32(b->out + s->out_start, 1.2596 ++ b->out_pos - s->out_start, s->crc32); 1.2597 ++ 1.2598 ++ if (ret == XZ_STREAM_END) { 1.2599 ++ if (s->block_header.compressed != VLI_UNKNOWN 1.2600 ++ && s->block_header.compressed 1.2601 ++ != s->block.compressed) 1.2602 ++ return XZ_DATA_ERROR; 1.2603 ++ 1.2604 ++ if (s->block_header.uncompressed != VLI_UNKNOWN 1.2605 ++ && s->block_header.uncompressed 1.2606 ++ != s->block.uncompressed) 1.2607 ++ return XZ_DATA_ERROR; 1.2608 ++ 1.2609 ++ s->block.hash.unpadded += s->block_header.size 1.2610 ++ + s->block.compressed; 1.2611 ++ 1.2612 ++#ifdef XZ_DEC_ANY_CHECK 1.2613 ++ s->block.hash.unpadded += check_sizes[s->check_type]; 1.2614 ++#else 1.2615 ++ if (s->check_type == XZ_CHECK_CRC32) 1.2616 ++ s->block.hash.unpadded += 4; 1.2617 ++#endif 1.2618 ++ 1.2619 ++ s->block.hash.uncompressed += s->block.uncompressed; 1.2620 ++ s->block.hash.crc32 = xz_crc32( 1.2621 ++ (const uint8_t *)&s->block.hash, 1.2622 ++ sizeof(s->block.hash), s->block.hash.crc32); 1.2623 ++ 1.2624 ++ ++s->block.count; 1.2625 ++ } 1.2626 ++ 1.2627 ++ return ret; 1.2628 ++} 1.2629 ++ 1.2630 ++/* Update the Index size and the CRC32 value. */ 1.2631 ++static void index_update(struct xz_dec *s, const struct xz_buf *b) 1.2632 ++{ 1.2633 ++ size_t in_used = b->in_pos - s->in_start; 1.2634 ++ s->index.size += in_used; 1.2635 ++ s->crc32 = xz_crc32(b->in + s->in_start, in_used, s->crc32); 1.2636 ++} 1.2637 ++ 1.2638 ++/* 1.2639 ++ * Decode the Number of Records, Unpadded Size, and Uncompressed Size 1.2640 ++ * fields from the Index field. That is, Index Padding and CRC32 are not 1.2641 ++ * decoded by this function. 1.2642 ++ * 1.2643 ++ * This can return XZ_OK (more input needed), XZ_STREAM_END (everything 1.2644 ++ * successfully decoded), or XZ_DATA_ERROR (input is corrupt). 1.2645 ++ */ 1.2646 ++static enum xz_ret dec_index(struct xz_dec *s, struct xz_buf *b) 1.2647 ++{ 1.2648 ++ enum xz_ret ret; 1.2649 ++ 1.2650 ++ do { 1.2651 ++ ret = dec_vli(s, b->in, &b->in_pos, b->in_size); 1.2652 ++ if (ret != XZ_STREAM_END) { 1.2653 ++ index_update(s, b); 1.2654 ++ return ret; 1.2655 ++ } 1.2656 ++ 1.2657 ++ switch (s->index.sequence) { 1.2658 ++ case SEQ_INDEX_COUNT: 1.2659 ++ s->index.count = s->vli; 1.2660 ++ 1.2661 ++ /* 1.2662 ++ * Validate that the Number of Records field 1.2663 ++ * indicates the same number of Records as 1.2664 ++ * there were Blocks in the Stream. 1.2665 ++ */ 1.2666 ++ if (s->index.count != s->block.count) 1.2667 ++ return XZ_DATA_ERROR; 1.2668 ++ 1.2669 ++ s->index.sequence = SEQ_INDEX_UNPADDED; 1.2670 ++ break; 1.2671 ++ 1.2672 ++ case SEQ_INDEX_UNPADDED: 1.2673 ++ s->index.hash.unpadded += s->vli; 1.2674 ++ s->index.sequence = SEQ_INDEX_UNCOMPRESSED; 1.2675 ++ break; 1.2676 ++ 1.2677 ++ case SEQ_INDEX_UNCOMPRESSED: 1.2678 ++ s->index.hash.uncompressed += s->vli; 1.2679 ++ s->index.hash.crc32 = xz_crc32( 1.2680 ++ (const uint8_t *)&s->index.hash, 1.2681 ++ sizeof(s->index.hash), 1.2682 ++ s->index.hash.crc32); 1.2683 ++ --s->index.count; 1.2684 ++ s->index.sequence = SEQ_INDEX_UNPADDED; 1.2685 ++ break; 1.2686 ++ } 1.2687 ++ } while (s->index.count > 0); 1.2688 ++ 1.2689 ++ return XZ_STREAM_END; 1.2690 ++} 1.2691 ++ 1.2692 ++/* 1.2693 ++ * Validate that the next four input bytes match the value of s->crc32. 1.2694 ++ * s->pos must be zero when starting to validate the first byte. 1.2695 ++ */ 1.2696 ++static enum xz_ret crc32_validate(struct xz_dec *s, struct xz_buf *b) 1.2697 ++{ 1.2698 ++ do { 1.2699 ++ if (b->in_pos == b->in_size) 1.2700 ++ return XZ_OK; 1.2701 ++ 1.2702 ++ if (((s->crc32 >> s->pos) & 0xFF) != b->in[b->in_pos++]) 1.2703 ++ return XZ_DATA_ERROR; 1.2704 ++ 1.2705 ++ s->pos += 8; 1.2706 ++ 1.2707 ++ } while (s->pos < 32); 1.2708 ++ 1.2709 ++ s->crc32 = 0; 1.2710 ++ s->pos = 0; 1.2711 ++ 1.2712 ++ return XZ_STREAM_END; 1.2713 ++} 1.2714 ++ 1.2715 ++#ifdef XZ_DEC_ANY_CHECK 1.2716 ++/* 1.2717 ++ * Skip over the Check field when the Check ID is not supported. 1.2718 ++ * Returns true once the whole Check field has been skipped over. 1.2719 ++ */ 1.2720 ++static bool check_skip(struct xz_dec *s, struct xz_buf *b) 1.2721 ++{ 1.2722 ++ while (s->pos < check_sizes[s->check_type]) { 1.2723 ++ if (b->in_pos == b->in_size) 1.2724 ++ return false; 1.2725 ++ 1.2726 ++ ++b->in_pos; 1.2727 ++ ++s->pos; 1.2728 ++ } 1.2729 ++ 1.2730 ++ s->pos = 0; 1.2731 ++ 1.2732 ++ return true; 1.2733 ++} 1.2734 ++#endif 1.2735 ++ 1.2736 ++/* Decode the Stream Header field (the first 12 bytes of the .xz Stream). */ 1.2737 ++static enum xz_ret dec_stream_header(struct xz_dec *s) 1.2738 ++{ 1.2739 ++ if (!memeq(s->temp.buf, HEADER_MAGIC, HEADER_MAGIC_SIZE)) 1.2740 ++ return XZ_FORMAT_ERROR; 1.2741 ++ 1.2742 ++ if (xz_crc32(s->temp.buf + HEADER_MAGIC_SIZE, 2, 0) 1.2743 ++ != get_le32(s->temp.buf + HEADER_MAGIC_SIZE + 2)) 1.2744 ++ return XZ_DATA_ERROR; 1.2745 ++ 1.2746 ++ if (s->temp.buf[HEADER_MAGIC_SIZE] != 0) 1.2747 ++ return XZ_OPTIONS_ERROR; 1.2748 ++ 1.2749 ++ /* 1.2750 ++ * Of integrity checks, we support only none (Check ID = 0) and 1.2751 ++ * CRC32 (Check ID = 1). However, if XZ_DEC_ANY_CHECK is defined, 1.2752 ++ * we will accept other check types too, but then the check won't 1.2753 ++ * be verified and a warning (XZ_UNSUPPORTED_CHECK) will be given. 1.2754 ++ */ 1.2755 ++ s->check_type = s->temp.buf[HEADER_MAGIC_SIZE + 1]; 1.2756 ++ 1.2757 ++#ifdef XZ_DEC_ANY_CHECK 1.2758 ++ if (s->check_type > XZ_CHECK_MAX) 1.2759 ++ return XZ_OPTIONS_ERROR; 1.2760 ++ 1.2761 ++ if (s->check_type > XZ_CHECK_CRC32) 1.2762 ++ return XZ_UNSUPPORTED_CHECK; 1.2763 ++#else 1.2764 ++ if (s->check_type > XZ_CHECK_CRC32) 1.2765 ++ return XZ_OPTIONS_ERROR; 1.2766 ++#endif 1.2767 ++ 1.2768 ++ return XZ_OK; 1.2769 ++} 1.2770 ++ 1.2771 ++/* Decode the Stream Footer field (the last 12 bytes of the .xz Stream) */ 1.2772 ++static enum xz_ret dec_stream_footer(struct xz_dec *s) 1.2773 ++{ 1.2774 ++ if (!memeq(s->temp.buf + 10, FOOTER_MAGIC, FOOTER_MAGIC_SIZE)) 1.2775 ++ return XZ_DATA_ERROR; 1.2776 ++ 1.2777 ++ if (xz_crc32(s->temp.buf + 4, 6, 0) != get_le32(s->temp.buf)) 1.2778 ++ return XZ_DATA_ERROR; 1.2779 ++ 1.2780 ++ /* 1.2781 ++ * Validate Backward Size. Note that we never added the size of the 1.2782 ++ * Index CRC32 field to s->index.size, thus we use s->index.size / 4 1.2783 ++ * instead of s->index.size / 4 - 1. 1.2784 ++ */ 1.2785 ++ if ((s->index.size >> 2) != get_le32(s->temp.buf + 4)) 1.2786 ++ return XZ_DATA_ERROR; 1.2787 ++ 1.2788 ++ if (s->temp.buf[8] != 0 || s->temp.buf[9] != s->check_type) 1.2789 ++ return XZ_DATA_ERROR; 1.2790 ++ 1.2791 ++ /* 1.2792 ++ * Use XZ_STREAM_END instead of XZ_OK to be more convenient 1.2793 ++ * for the caller. 1.2794 ++ */ 1.2795 ++ return XZ_STREAM_END; 1.2796 ++} 1.2797 ++ 1.2798 ++/* Decode the Block Header and initialize the filter chain. */ 1.2799 ++static enum xz_ret dec_block_header(struct xz_dec *s) 1.2800 ++{ 1.2801 ++ enum xz_ret ret; 1.2802 ++ 1.2803 ++ /* 1.2804 ++ * Validate the CRC32. We know that the temp buffer is at least 1.2805 ++ * eight bytes so this is safe. 1.2806 ++ */ 1.2807 ++ s->temp.size -= 4; 1.2808 ++ if (xz_crc32(s->temp.buf, s->temp.size, 0) 1.2809 ++ != get_le32(s->temp.buf + s->temp.size)) 1.2810 ++ return XZ_DATA_ERROR; 1.2811 ++ 1.2812 ++ s->temp.pos = 2; 1.2813 ++ 1.2814 ++ /* 1.2815 ++ * Catch unsupported Block Flags. We support only one or two filters 1.2816 ++ * in the chain, so we catch that with the same test. 1.2817 ++ */ 1.2818 ++#ifdef XZ_DEC_BCJ 1.2819 ++ if (s->temp.buf[1] & 0x3E) 1.2820 ++#else 1.2821 ++ if (s->temp.buf[1] & 0x3F) 1.2822 ++#endif 1.2823 ++ return XZ_OPTIONS_ERROR; 1.2824 ++ 1.2825 ++ /* Compressed Size */ 1.2826 ++ if (s->temp.buf[1] & 0x40) { 1.2827 ++ if (dec_vli(s, s->temp.buf, &s->temp.pos, s->temp.size) 1.2828 ++ != XZ_STREAM_END) 1.2829 ++ return XZ_DATA_ERROR; 1.2830 ++ 1.2831 ++ s->block_header.compressed = s->vli; 1.2832 ++ } else { 1.2833 ++ s->block_header.compressed = VLI_UNKNOWN; 1.2834 ++ } 1.2835 ++ 1.2836 ++ /* Uncompressed Size */ 1.2837 ++ if (s->temp.buf[1] & 0x80) { 1.2838 ++ if (dec_vli(s, s->temp.buf, &s->temp.pos, s->temp.size) 1.2839 ++ != XZ_STREAM_END) 1.2840 ++ return XZ_DATA_ERROR; 1.2841 ++ 1.2842 ++ s->block_header.uncompressed = s->vli; 1.2843 ++ } else { 1.2844 ++ s->block_header.uncompressed = VLI_UNKNOWN; 1.2845 ++ } 1.2846 ++ 1.2847 ++#ifdef XZ_DEC_BCJ 1.2848 ++ /* If there are two filters, the first one must be a BCJ filter. */ 1.2849 ++ s->bcj_active = s->temp.buf[1] & 0x01; 1.2850 ++ if (s->bcj_active) { 1.2851 ++ if (s->temp.size - s->temp.pos < 2) 1.2852 ++ return XZ_OPTIONS_ERROR; 1.2853 ++ 1.2854 ++ ret = xz_dec_bcj_reset(s->bcj, s->temp.buf[s->temp.pos++]); 1.2855 ++ if (ret != XZ_OK) 1.2856 ++ return ret; 1.2857 ++ 1.2858 ++ /* 1.2859 ++ * We don't support custom start offset, 1.2860 ++ * so Size of Properties must be zero. 1.2861 ++ */ 1.2862 ++ if (s->temp.buf[s->temp.pos++] != 0x00) 1.2863 ++ return XZ_OPTIONS_ERROR; 1.2864 ++ } 1.2865 ++#endif 1.2866 ++ 1.2867 ++ /* Valid Filter Flags always take at least two bytes. */ 1.2868 ++ if (s->temp.size - s->temp.pos < 2) 1.2869 ++ return XZ_DATA_ERROR; 1.2870 ++ 1.2871 ++ /* Filter ID = LZMA2 */ 1.2872 ++ if (s->temp.buf[s->temp.pos++] != 0x21) 1.2873 ++ return XZ_OPTIONS_ERROR; 1.2874 ++ 1.2875 ++ /* Size of Properties = 1-byte Filter Properties */ 1.2876 ++ if (s->temp.buf[s->temp.pos++] != 0x01) 1.2877 ++ return XZ_OPTIONS_ERROR; 1.2878 ++ 1.2879 ++ /* Filter Properties contains LZMA2 dictionary size. */ 1.2880 ++ if (s->temp.size - s->temp.pos < 1) 1.2881 ++ return XZ_DATA_ERROR; 1.2882 ++ 1.2883 ++ ret = xz_dec_lzma2_reset(s->lzma2, s->temp.buf[s->temp.pos++]); 1.2884 ++ if (ret != XZ_OK) 1.2885 ++ return ret; 1.2886 ++ 1.2887 ++ /* The rest must be Header Padding. */ 1.2888 ++ while (s->temp.pos < s->temp.size) 1.2889 ++ if (s->temp.buf[s->temp.pos++] != 0x00) 1.2890 ++ return XZ_OPTIONS_ERROR; 1.2891 ++ 1.2892 ++ s->temp.pos = 0; 1.2893 ++ s->block.compressed = 0; 1.2894 ++ s->block.uncompressed = 0; 1.2895 ++ 1.2896 ++ return XZ_OK; 1.2897 ++} 1.2898 ++ 1.2899 ++static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b) 1.2900 ++{ 1.2901 ++ enum xz_ret ret; 1.2902 ++ 1.2903 ++ /* 1.2904 ++ * Store the start position for the case when we are in the middle 1.2905 ++ * of the Index field. 1.2906 ++ */ 1.2907 ++ s->in_start = b->in_pos; 1.2908 ++ 1.2909 ++ while (true) { 1.2910 ++ switch (s->sequence) { 1.2911 ++ case SEQ_STREAM_HEADER: 1.2912 ++ /* 1.2913 ++ * Stream Header is copied to s->temp, and then 1.2914 ++ * decoded from there. This way if the caller 1.2915 ++ * gives us only little input at a time, we can 1.2916 ++ * still keep the Stream Header decoding code 1.2917 ++ * simple. Similar approach is used in many places 1.2918 ++ * in this file. 1.2919 ++ */ 1.2920 ++ if (!fill_temp(s, b)) 1.2921 ++ return XZ_OK; 1.2922 ++ 1.2923 ++ /* 1.2924 ++ * If dec_stream_header() returns 1.2925 ++ * XZ_UNSUPPORTED_CHECK, it is still possible 1.2926 ++ * to continue decoding if working in multi-call 1.2927 ++ * mode. Thus, update s->sequence before calling 1.2928 ++ * dec_stream_header(). 1.2929 ++ */ 1.2930 ++ s->sequence = SEQ_BLOCK_START; 1.2931 ++ 1.2932 ++ ret = dec_stream_header(s); 1.2933 ++ if (ret != XZ_OK) 1.2934 ++ return ret; 1.2935 ++ 1.2936 ++ case SEQ_BLOCK_START: 1.2937 ++ /* We need one byte of input to continue. */ 1.2938 ++ if (b->in_pos == b->in_size) 1.2939 ++ return XZ_OK; 1.2940 ++ 1.2941 ++ /* See if this is the beginning of the Index field. */ 1.2942 ++ if (b->in[b->in_pos] == 0) { 1.2943 ++ s->in_start = b->in_pos++; 1.2944 ++ s->sequence = SEQ_INDEX; 1.2945 ++ break; 1.2946 ++ } 1.2947 ++ 1.2948 ++ /* 1.2949 ++ * Calculate the size of the Block Header and 1.2950 ++ * prepare to decode it. 1.2951 ++ */ 1.2952 ++ s->block_header.size 1.2953 ++ = ((uint32_t)b->in[b->in_pos] + 1) * 4; 1.2954 ++ 1.2955 ++ s->temp.size = s->block_header.size; 1.2956 ++ s->temp.pos = 0; 1.2957 ++ s->sequence = SEQ_BLOCK_HEADER; 1.2958 ++ 1.2959 ++ case SEQ_BLOCK_HEADER: 1.2960 ++ if (!fill_temp(s, b)) 1.2961 ++ return XZ_OK; 1.2962 ++ 1.2963 ++ ret = dec_block_header(s); 1.2964 ++ if (ret != XZ_OK) 1.2965 ++ return ret; 1.2966 ++ 1.2967 ++ s->sequence = SEQ_BLOCK_UNCOMPRESS; 1.2968 ++ 1.2969 ++ case SEQ_BLOCK_UNCOMPRESS: 1.2970 ++ ret = dec_block(s, b); 1.2971 ++ if (ret != XZ_STREAM_END) 1.2972 ++ return ret; 1.2973 ++ 1.2974 ++ s->sequence = SEQ_BLOCK_PADDING; 1.2975 ++ 1.2976 ++ case SEQ_BLOCK_PADDING: 1.2977 ++ /* 1.2978 ++ * Size of Compressed Data + Block Padding 1.2979 ++ * must be a multiple of four. We don't need 1.2980 ++ * s->block.compressed for anything else 1.2981 ++ * anymore, so we use it here to test the size 1.2982 ++ * of the Block Padding field. 1.2983 ++ */ 1.2984 ++ while (s->block.compressed & 3) { 1.2985 ++ if (b->in_pos == b->in_size) 1.2986 ++ return XZ_OK; 1.2987 ++ 1.2988 ++ if (b->in[b->in_pos++] != 0) 1.2989 ++ return XZ_DATA_ERROR; 1.2990 ++ 1.2991 ++ ++s->block.compressed; 1.2992 ++ } 1.2993 ++ 1.2994 ++ s->sequence = SEQ_BLOCK_CHECK; 1.2995 ++ 1.2996 ++ case SEQ_BLOCK_CHECK: 1.2997 ++ if (s->check_type == XZ_CHECK_CRC32) { 1.2998 ++ ret = crc32_validate(s, b); 1.2999 ++ if (ret != XZ_STREAM_END) 1.3000 ++ return ret; 1.3001 ++ } 1.3002 ++#ifdef XZ_DEC_ANY_CHECK 1.3003 ++ else if (!check_skip(s, b)) { 1.3004 ++ return XZ_OK; 1.3005 ++ } 1.3006 ++#endif 1.3007 ++ 1.3008 ++ s->sequence = SEQ_BLOCK_START; 1.3009 ++ break; 1.3010 ++ 1.3011 ++ case SEQ_INDEX: 1.3012 ++ ret = dec_index(s, b); 1.3013 ++ if (ret != XZ_STREAM_END) 1.3014 ++ return ret; 1.3015 ++ 1.3016 ++ s->sequence = SEQ_INDEX_PADDING; 1.3017 ++ 1.3018 ++ case SEQ_INDEX_PADDING: 1.3019 ++ while ((s->index.size + (b->in_pos - s->in_start)) 1.3020 ++ & 3) { 1.3021 ++ if (b->in_pos == b->in_size) { 1.3022 ++ index_update(s, b); 1.3023 ++ return XZ_OK; 1.3024 ++ } 1.3025 ++ 1.3026 ++ if (b->in[b->in_pos++] != 0) 1.3027 ++ return XZ_DATA_ERROR; 1.3028 ++ } 1.3029 ++ 1.3030 ++ /* Finish the CRC32 value and Index size. */ 1.3031 ++ index_update(s, b); 1.3032 ++ 1.3033 ++ /* Compare the hashes to validate the Index field. */ 1.3034 ++ if (!memeq(&s->block.hash, &s->index.hash, 1.3035 ++ sizeof(s->block.hash))) 1.3036 ++ return XZ_DATA_ERROR; 1.3037 ++ 1.3038 ++ s->sequence = SEQ_INDEX_CRC32; 1.3039 ++ 1.3040 ++ case SEQ_INDEX_CRC32: 1.3041 ++ ret = crc32_validate(s, b); 1.3042 ++ if (ret != XZ_STREAM_END) 1.3043 ++ return ret; 1.3044 ++ 1.3045 ++ s->temp.size = STREAM_HEADER_SIZE; 1.3046 ++ s->sequence = SEQ_STREAM_FOOTER; 1.3047 ++ 1.3048 ++ case SEQ_STREAM_FOOTER: 1.3049 ++ if (!fill_temp(s, b)) 1.3050 ++ return XZ_OK; 1.3051 ++ 1.3052 ++ return dec_stream_footer(s); 1.3053 ++ } 1.3054 ++ } 1.3055 ++ 1.3056 ++ /* Never reached */ 1.3057 ++} 1.3058 ++ 1.3059 ++/* 1.3060 ++ * xz_dec_run() is a wrapper for dec_main() to handle some special cases in 1.3061 ++ * multi-call and single-call decoding. 1.3062 ++ * 1.3063 ++ * In multi-call mode, we must return XZ_BUF_ERROR when it seems clear that we 1.3064 ++ * are not going to make any progress anymore. This is to prevent the caller 1.3065 ++ * from calling us infinitely when the input file is truncated or otherwise 1.3066 ++ * corrupt. Since zlib-style API allows that the caller fills the input buffer 1.3067 ++ * only when the decoder doesn't produce any new output, we have to be careful 1.3068 ++ * to avoid returning XZ_BUF_ERROR too easily: XZ_BUF_ERROR is returned only 1.3069 ++ * after the second consecutive call to xz_dec_run() that makes no progress. 1.3070 ++ * 1.3071 ++ * In single-call mode, if we couldn't decode everything and no error 1.3072 ++ * occurred, either the input is truncated or the output buffer is too small. 1.3073 ++ * Since we know that the last input byte never produces any output, we know 1.3074 ++ * that if all the input was consumed and decoding wasn't finished, the file 1.3075 ++ * must be corrupt. Otherwise the output buffer has to be too small or the 1.3076 ++ * file is corrupt in a way that decoding it produces too big output. 1.3077 ++ * 1.3078 ++ * If single-call decoding fails, we reset b->in_pos and b->out_pos back to 1.3079 ++ * their original values. This is because with some filter chains there won't 1.3080 ++ * be any valid uncompressed data in the output buffer unless the decoding 1.3081 ++ * actually succeeds (that's the price to pay of using the output buffer as 1.3082 ++ * the workspace). 1.3083 ++ */ 1.3084 ++XZ_EXTERN enum xz_ret xz_dec_run(struct xz_dec *s, struct xz_buf *b) 1.3085 ++{ 1.3086 ++ size_t in_start; 1.3087 ++ size_t out_start; 1.3088 ++ enum xz_ret ret; 1.3089 ++ 1.3090 ++ if (DEC_IS_SINGLE(s->mode)) 1.3091 ++ xz_dec_reset(s); 1.3092 ++ 1.3093 ++ in_start = b->in_pos; 1.3094 ++ out_start = b->out_pos; 1.3095 ++ ret = dec_main(s, b); 1.3096 ++ 1.3097 ++ if (DEC_IS_SINGLE(s->mode)) { 1.3098 ++ if (ret == XZ_OK) 1.3099 ++ ret = b->in_pos == b->in_size 1.3100 ++ ? XZ_DATA_ERROR : XZ_BUF_ERROR; 1.3101 ++ 1.3102 ++ if (ret != XZ_STREAM_END) { 1.3103 ++ b->in_pos = in_start; 1.3104 ++ b->out_pos = out_start; 1.3105 ++ } 1.3106 ++ 1.3107 ++ } else if (ret == XZ_OK && in_start == b->in_pos 1.3108 ++ && out_start == b->out_pos) { 1.3109 ++ if (s->allow_buf_error) 1.3110 ++ ret = XZ_BUF_ERROR; 1.3111 ++ 1.3112 ++ s->allow_buf_error = true; 1.3113 ++ } else { 1.3114 ++ s->allow_buf_error = false; 1.3115 ++ } 1.3116 ++ 1.3117 ++ return ret; 1.3118 ++} 1.3119 ++ 1.3120 ++XZ_EXTERN struct xz_dec *xz_dec_init(enum xz_mode mode, uint32_t dict_max) 1.3121 ++{ 1.3122 ++ struct xz_dec *s = kmalloc(sizeof(*s), GFP_KERNEL); 1.3123 ++ if (s == NULL) 1.3124 ++ return NULL; 1.3125 ++ 1.3126 ++ s->mode = mode; 1.3127 ++ 1.3128 ++#ifdef XZ_DEC_BCJ 1.3129 ++ s->bcj = xz_dec_bcj_create(DEC_IS_SINGLE(mode)); 1.3130 ++ if (s->bcj == NULL) 1.3131 ++ goto error_bcj; 1.3132 ++#endif 1.3133 ++ 1.3134 ++ s->lzma2 = xz_dec_lzma2_create(mode, dict_max); 1.3135 ++ if (s->lzma2 == NULL) 1.3136 ++ goto error_lzma2; 1.3137 ++ 1.3138 ++ xz_dec_reset(s); 1.3139 ++ return s; 1.3140 ++ 1.3141 ++error_lzma2: 1.3142 ++#ifdef XZ_DEC_BCJ 1.3143 ++ xz_dec_bcj_end(s->bcj); 1.3144 ++error_bcj: 1.3145 ++#endif 1.3146 ++ kfree(s); 1.3147 ++ return NULL; 1.3148 ++} 1.3149 ++ 1.3150 ++XZ_EXTERN void xz_dec_reset(struct xz_dec *s) 1.3151 ++{ 1.3152 ++ s->sequence = SEQ_STREAM_HEADER; 1.3153 ++ s->allow_buf_error = false; 1.3154 ++ s->pos = 0; 1.3155 ++ s->crc32 = 0; 1.3156 ++ memzero(&s->block, sizeof(s->block)); 1.3157 ++ memzero(&s->index, sizeof(s->index)); 1.3158 ++ s->temp.pos = 0; 1.3159 ++ s->temp.size = STREAM_HEADER_SIZE; 1.3160 ++} 1.3161 ++ 1.3162 ++XZ_EXTERN void xz_dec_end(struct xz_dec *s) 1.3163 ++{ 1.3164 ++ if (s != NULL) { 1.3165 ++ xz_dec_lzma2_end(s->lzma2); 1.3166 ++#ifdef XZ_DEC_BCJ 1.3167 ++ xz_dec_bcj_end(s->bcj); 1.3168 ++#endif 1.3169 ++ kfree(s); 1.3170 ++ } 1.3171 ++} 1.3172 +diff --git a/lib/xz/xz_dec_syms.c b/lib/xz/xz_dec_syms.c 1.3173 +new file mode 100644 1.3174 +index 0000000..32eb3c0 1.3175 +--- /dev/null 1.3176 ++++ b/lib/xz/xz_dec_syms.c 1.3177 +@@ -0,0 +1,26 @@ 1.3178 ++/* 1.3179 ++ * XZ decoder module information 1.3180 ++ * 1.3181 ++ * Author: Lasse Collin <lasse.collin@tukaani.org> 1.3182 ++ * 1.3183 ++ * This file has been put into the public domain. 1.3184 ++ * You can do whatever you want with this file. 1.3185 ++ */ 1.3186 ++ 1.3187 ++#include <linux/module.h> 1.3188 ++#include <linux/xz.h> 1.3189 ++ 1.3190 ++EXPORT_SYMBOL(xz_dec_init); 1.3191 ++EXPORT_SYMBOL(xz_dec_reset); 1.3192 ++EXPORT_SYMBOL(xz_dec_run); 1.3193 ++EXPORT_SYMBOL(xz_dec_end); 1.3194 ++ 1.3195 ++MODULE_DESCRIPTION("XZ decompressor"); 1.3196 ++MODULE_VERSION("1.0"); 1.3197 ++MODULE_AUTHOR("Lasse Collin <lasse.collin@tukaani.org> and Igor Pavlov"); 1.3198 ++ 1.3199 ++/* 1.3200 ++ * This code is in the public domain, but in Linux it's simplest to just 1.3201 ++ * say it's GPL and consider the authors as the copyright holders. 1.3202 ++ */ 1.3203 ++MODULE_LICENSE("GPL"); 1.3204 +diff --git a/lib/xz/xz_dec_test.c b/lib/xz/xz_dec_test.c 1.3205 +new file mode 100644 1.3206 +index 0000000..da28a19 1.3207 +--- /dev/null 1.3208 ++++ b/lib/xz/xz_dec_test.c 1.3209 +@@ -0,0 +1,220 @@ 1.3210 ++/* 1.3211 ++ * XZ decoder tester 1.3212 ++ * 1.3213 ++ * Author: Lasse Collin <lasse.collin@tukaani.org> 1.3214 ++ * 1.3215 ++ * This file has been put into the public domain. 1.3216 ++ * You can do whatever you want with this file. 1.3217 ++ */ 1.3218 ++ 1.3219 ++#include <linux/kernel.h> 1.3220 ++#include <linux/module.h> 1.3221 ++#include <linux/fs.h> 1.3222 ++#include <linux/uaccess.h> 1.3223 ++#include <linux/crc32.h> 1.3224 ++#include <linux/xz.h> 1.3225 ++ 1.3226 ++/* Maximum supported dictionary size */ 1.3227 ++#define DICT_MAX (1 << 20) 1.3228 ++ 1.3229 ++/* Device name to pass to register_chrdev(). */ 1.3230 ++#define DEVICE_NAME "xz_dec_test" 1.3231 ++ 1.3232 ++/* Dynamically allocated device major number */ 1.3233 ++static int device_major; 1.3234 ++ 1.3235 ++/* 1.3236 ++ * We reuse the same decoder state, and thus can decode only one 1.3237 ++ * file at a time. 1.3238 ++ */ 1.3239 ++static bool device_is_open; 1.3240 ++ 1.3241 ++/* XZ decoder state */ 1.3242 ++static struct xz_dec *state; 1.3243 ++ 1.3244 ++/* 1.3245 ++ * Return value of xz_dec_run(). We need to avoid calling xz_dec_run() after 1.3246 ++ * it has returned XZ_STREAM_END, so we make this static. 1.3247 ++ */ 1.3248 ++static enum xz_ret ret; 1.3249 ++ 1.3250 ++/* 1.3251 ++ * Input and output buffers. The input buffer is used as a temporary safe 1.3252 ++ * place for the data coming from the userspace. 1.3253 ++ */ 1.3254 ++static uint8_t buffer_in[1024]; 1.3255 ++static uint8_t buffer_out[1024]; 1.3256 ++ 1.3257 ++/* 1.3258 ++ * Structure to pass the input and output buffers to the XZ decoder. 1.3259 ++ * A few of the fields are never modified so we initialize them here. 1.3260 ++ */ 1.3261 ++static struct xz_buf buffers = { 1.3262 ++ .in = buffer_in, 1.3263 ++ .out = buffer_out, 1.3264 ++ .out_size = sizeof(buffer_out) 1.3265 ++}; 1.3266 ++ 1.3267 ++/* 1.3268 ++ * CRC32 of uncompressed data. This is used to give the user a simple way 1.3269 ++ * to check that the decoder produces correct output. 1.3270 ++ */ 1.3271 ++static uint32_t crc; 1.3272 ++ 1.3273 ++static int xz_dec_test_open(struct inode *i, struct file *f) 1.3274 ++{ 1.3275 ++ if (device_is_open) 1.3276 ++ return -EBUSY; 1.3277 ++ 1.3278 ++ device_is_open = true; 1.3279 ++ 1.3280 ++ xz_dec_reset(state); 1.3281 ++ ret = XZ_OK; 1.3282 ++ crc = 0xFFFFFFFF; 1.3283 ++ 1.3284 ++ buffers.in_pos = 0; 1.3285 ++ buffers.in_size = 0; 1.3286 ++ buffers.out_pos = 0; 1.3287 ++ 1.3288 ++ printk(KERN_INFO DEVICE_NAME ": opened\n"); 1.3289 ++ return 0; 1.3290 ++} 1.3291 ++ 1.3292 ++static int xz_dec_test_release(struct inode *i, struct file *f) 1.3293 ++{ 1.3294 ++ device_is_open = false; 1.3295 ++ 1.3296 ++ if (ret == XZ_OK) 1.3297 ++ printk(KERN_INFO DEVICE_NAME ": input was truncated\n"); 1.3298 ++ 1.3299 ++ printk(KERN_INFO DEVICE_NAME ": closed\n"); 1.3300 ++ return 0; 1.3301 ++} 1.3302 ++ 1.3303 ++/* 1.3304 ++ * Decode the data given to us from the userspace. CRC32 of the uncompressed 1.3305 ++ * data is calculated and is printed at the end of successful decoding. The 1.3306 ++ * uncompressed data isn't stored anywhere for further use. 1.3307 ++ * 1.3308 ++ * The .xz file must have exactly one Stream and no Stream Padding. The data 1.3309 ++ * after the first Stream is considered to be garbage. 1.3310 ++ */ 1.3311 ++static ssize_t xz_dec_test_write(struct file *file, const char __user *buf, 1.3312 ++ size_t size, loff_t *pos) 1.3313 ++{ 1.3314 ++ size_t remaining; 1.3315 ++ 1.3316 ++ if (ret != XZ_OK) { 1.3317 ++ if (size > 0) 1.3318 ++ printk(KERN_INFO DEVICE_NAME ": %zu bytes of " 1.3319 ++ "garbage at the end of the file\n", 1.3320 ++ size); 1.3321 ++ 1.3322 ++ return -ENOSPC; 1.3323 ++ } 1.3324 ++ 1.3325 ++ printk(KERN_INFO DEVICE_NAME ": decoding %zu bytes of input\n", 1.3326 ++ size); 1.3327 ++ 1.3328 ++ remaining = size; 1.3329 ++ while ((remaining > 0 || buffers.out_pos == buffers.out_size) 1.3330 ++ && ret == XZ_OK) { 1.3331 ++ if (buffers.in_pos == buffers.in_size) { 1.3332 ++ buffers.in_pos = 0; 1.3333 ++ buffers.in_size = min(remaining, sizeof(buffer_in)); 1.3334 ++ if (copy_from_user(buffer_in, buf, buffers.in_size)) 1.3335 ++ return -EFAULT; 1.3336 ++ 1.3337 ++ buf += buffers.in_size; 1.3338 ++ remaining -= buffers.in_size; 1.3339 ++ } 1.3340 ++ 1.3341 ++ buffers.out_pos = 0; 1.3342 ++ ret = xz_dec_run(state, &buffers); 1.3343 ++ crc = crc32(crc, buffer_out, buffers.out_pos); 1.3344 ++ } 1.3345 ++ 1.3346 ++ switch (ret) { 1.3347 ++ case XZ_OK: 1.3348 ++ printk(KERN_INFO DEVICE_NAME ": XZ_OK\n"); 1.3349 ++ return size; 1.3350 ++ 1.3351 ++ case XZ_STREAM_END: 1.3352 ++ printk(KERN_INFO DEVICE_NAME ": XZ_STREAM_END, " 1.3353 ++ "CRC32 = 0x%08X\n", ~crc); 1.3354 ++ return size - remaining - (buffers.in_size - buffers.in_pos); 1.3355 ++ 1.3356 ++ case XZ_MEMLIMIT_ERROR: 1.3357 ++ printk(KERN_INFO DEVICE_NAME ": XZ_MEMLIMIT_ERROR\n"); 1.3358 ++ break; 1.3359 ++ 1.3360 ++ case XZ_FORMAT_ERROR: 1.3361 ++ printk(KERN_INFO DEVICE_NAME ": XZ_FORMAT_ERROR\n"); 1.3362 ++ break; 1.3363 ++ 1.3364 ++ case XZ_OPTIONS_ERROR: 1.3365 ++ printk(KERN_INFO DEVICE_NAME ": XZ_OPTIONS_ERROR\n"); 1.3366 ++ break; 1.3367 ++ 1.3368 ++ case XZ_DATA_ERROR: 1.3369 ++ printk(KERN_INFO DEVICE_NAME ": XZ_DATA_ERROR\n"); 1.3370 ++ break; 1.3371 ++ 1.3372 ++ case XZ_BUF_ERROR: 1.3373 ++ printk(KERN_INFO DEVICE_NAME ": XZ_BUF_ERROR\n"); 1.3374 ++ break; 1.3375 ++ 1.3376 ++ default: 1.3377 ++ printk(KERN_INFO DEVICE_NAME ": Bug detected!\n"); 1.3378 ++ break; 1.3379 ++ } 1.3380 ++ 1.3381 ++ return -EIO; 1.3382 ++} 1.3383 ++ 1.3384 ++/* Allocate the XZ decoder state and register the character device. */ 1.3385 ++static int __init xz_dec_test_init(void) 1.3386 ++{ 1.3387 ++ static const struct file_operations fileops = { 1.3388 ++ .owner = THIS_MODULE, 1.3389 ++ .open = &xz_dec_test_open, 1.3390 ++ .release = &xz_dec_test_release, 1.3391 ++ .write = &xz_dec_test_write 1.3392 ++ }; 1.3393 ++ 1.3394 ++ state = xz_dec_init(XZ_PREALLOC, DICT_MAX); 1.3395 ++ if (state == NULL) 1.3396 ++ return -ENOMEM; 1.3397 ++ 1.3398 ++ device_major = register_chrdev(0, DEVICE_NAME, &fileops); 1.3399 ++ if (device_major < 0) { 1.3400 ++ xz_dec_end(state); 1.3401 ++ return device_major; 1.3402 ++ } 1.3403 ++ 1.3404 ++ printk(KERN_INFO DEVICE_NAME ": module loaded\n"); 1.3405 ++ printk(KERN_INFO DEVICE_NAME ": Create a device node with " 1.3406 ++ "'mknod " DEVICE_NAME " c %d 0' and write .xz files " 1.3407 ++ "to it.\n", device_major); 1.3408 ++ return 0; 1.3409 ++} 1.3410 ++ 1.3411 ++static void __exit xz_dec_test_exit(void) 1.3412 ++{ 1.3413 ++ unregister_chrdev(device_major, DEVICE_NAME); 1.3414 ++ xz_dec_end(state); 1.3415 ++ printk(KERN_INFO DEVICE_NAME ": module unloaded\n"); 1.3416 ++} 1.3417 ++ 1.3418 ++module_init(xz_dec_test_init); 1.3419 ++module_exit(xz_dec_test_exit); 1.3420 ++ 1.3421 ++MODULE_DESCRIPTION("XZ decompressor tester"); 1.3422 ++MODULE_VERSION("1.0"); 1.3423 ++MODULE_AUTHOR("Lasse Collin <lasse.collin@tukaani.org>"); 1.3424 ++ 1.3425 ++/* 1.3426 ++ * This code is in the public domain, but in Linux it's simplest to just 1.3427 ++ * say it's GPL and consider the authors as the copyright holders. 1.3428 ++ */ 1.3429 ++MODULE_LICENSE("GPL"); 1.3430 +diff --git a/lib/xz/xz_lzma2.h b/lib/xz/xz_lzma2.h 1.3431 +new file mode 100644 1.3432 +index 0000000..071d67b 1.3433 +--- /dev/null 1.3434 ++++ b/lib/xz/xz_lzma2.h 1.3435 +@@ -0,0 +1,204 @@ 1.3436 ++/* 1.3437 ++ * LZMA2 definitions 1.3438 ++ * 1.3439 ++ * Authors: Lasse Collin <lasse.collin@tukaani.org> 1.3440 ++ * Igor Pavlov <http://7-zip.org/> 1.3441 ++ * 1.3442 ++ * This file has been put into the public domain. 1.3443 ++ * You can do whatever you want with this file. 1.3444 ++ */ 1.3445 ++ 1.3446 ++#ifndef XZ_LZMA2_H 1.3447 ++#define XZ_LZMA2_H 1.3448 ++ 1.3449 ++/* Range coder constants */ 1.3450 ++#define RC_SHIFT_BITS 8 1.3451 ++#define RC_TOP_BITS 24 1.3452 ++#define RC_TOP_VALUE (1 << RC_TOP_BITS) 1.3453 ++#define RC_BIT_MODEL_TOTAL_BITS 11 1.3454 ++#define RC_BIT_MODEL_TOTAL (1 << RC_BIT_MODEL_TOTAL_BITS) 1.3455 ++#define RC_MOVE_BITS 5 1.3456 ++ 1.3457 ++/* 1.3458 ++ * Maximum number of position states. A position state is the lowest pb 1.3459 ++ * number of bits of the current uncompressed offset. In some places there 1.3460 ++ * are different sets of probabilities for different position states. 1.3461 ++ */ 1.3462 ++#define POS_STATES_MAX (1 << 4) 1.3463 ++ 1.3464 ++/* 1.3465 ++ * This enum is used to track which LZMA symbols have occurred most recently 1.3466 ++ * and in which order. This information is used to predict the next symbol. 1.3467 ++ * 1.3468 ++ * Symbols: 1.3469 ++ * - Literal: One 8-bit byte 1.3470 ++ * - Match: Repeat a chunk of data at some distance 1.3471 ++ * - Long repeat: Multi-byte match at a recently seen distance 1.3472 ++ * - Short repeat: One-byte repeat at a recently seen distance 1.3473 ++ * 1.3474 ++ * The symbol names are in from STATE_oldest_older_previous. REP means 1.3475 ++ * either short or long repeated match, and NONLIT means any non-literal. 1.3476 ++ */ 1.3477 ++enum lzma_state { 1.3478 ++ STATE_LIT_LIT, 1.3479 ++ STATE_MATCH_LIT_LIT, 1.3480 ++ STATE_REP_LIT_LIT, 1.3481 ++ STATE_SHORTREP_LIT_LIT, 1.3482 ++ STATE_MATCH_LIT, 1.3483 ++ STATE_REP_LIT, 1.3484 ++ STATE_SHORTREP_LIT, 1.3485 ++ STATE_LIT_MATCH, 1.3486 ++ STATE_LIT_LONGREP, 1.3487 ++ STATE_LIT_SHORTREP, 1.3488 ++ STATE_NONLIT_MATCH, 1.3489 ++ STATE_NONLIT_REP 1.3490 ++}; 1.3491 ++ 1.3492 ++/* Total number of states */ 1.3493 ++#define STATES 12 1.3494 ++ 1.3495 ++/* The lowest 7 states indicate that the previous state was a literal. */ 1.3496 ++#define LIT_STATES 7 1.3497 ++ 1.3498 ++/* Indicate that the latest symbol was a literal. */ 1.3499 ++static inline void lzma_state_literal(enum lzma_state *state) 1.3500 ++{ 1.3501 ++ if (*state <= STATE_SHORTREP_LIT_LIT) 1.3502 ++ *state = STATE_LIT_LIT; 1.3503 ++ else if (*state <= STATE_LIT_SHORTREP) 1.3504 ++ *state -= 3; 1.3505 ++ else 1.3506 ++ *state -= 6; 1.3507 ++} 1.3508 ++ 1.3509 ++/* Indicate that the latest symbol was a match. */ 1.3510 ++static inline void lzma_state_match(enum lzma_state *state) 1.3511 ++{ 1.3512 ++ *state = *state < LIT_STATES ? STATE_LIT_MATCH : STATE_NONLIT_MATCH; 1.3513 ++} 1.3514 ++ 1.3515 ++/* Indicate that the latest state was a long repeated match. */ 1.3516 ++static inline void lzma_state_long_rep(enum lzma_state *state) 1.3517 ++{ 1.3518 ++ *state = *state < LIT_STATES ? STATE_LIT_LONGREP : STATE_NONLIT_REP; 1.3519 ++} 1.3520 ++ 1.3521 ++/* Indicate that the latest symbol was a short match. */ 1.3522 ++static inline void lzma_state_short_rep(enum lzma_state *state) 1.3523 ++{ 1.3524 ++ *state = *state < LIT_STATES ? STATE_LIT_SHORTREP : STATE_NONLIT_REP; 1.3525 ++} 1.3526 ++ 1.3527 ++/* Test if the previous symbol was a literal. */ 1.3528 ++static inline bool lzma_state_is_literal(enum lzma_state state) 1.3529 ++{ 1.3530 ++ return state < LIT_STATES; 1.3531 ++} 1.3532 ++ 1.3533 ++/* Each literal coder is divided in three sections: 1.3534 ++ * - 0x001-0x0FF: Without match byte 1.3535 ++ * - 0x101-0x1FF: With match byte; match bit is 0 1.3536 ++ * - 0x201-0x2FF: With match byte; match bit is 1 1.3537 ++ * 1.3538 ++ * Match byte is used when the previous LZMA symbol was something else than 1.3539 ++ * a literal (that is, it was some kind of match). 1.3540 ++ */ 1.3541 ++#define LITERAL_CODER_SIZE 0x300 1.3542 ++ 1.3543 ++/* Maximum number of literal coders */ 1.3544 ++#define LITERAL_CODERS_MAX (1 << 4) 1.3545 ++ 1.3546 ++/* Minimum length of a match is two bytes. */ 1.3547 ++#define MATCH_LEN_MIN 2 1.3548 ++ 1.3549 ++/* Match length is encoded with 4, 5, or 10 bits. 1.3550 ++ * 1.3551 ++ * Length Bits 1.3552 ++ * 2-9 4 = Choice=0 + 3 bits 1.3553 ++ * 10-17 5 = Choice=1 + Choice2=0 + 3 bits 1.3554 ++ * 18-273 10 = Choice=1 + Choice2=1 + 8 bits 1.3555 ++ */ 1.3556 ++#define LEN_LOW_BITS 3 1.3557 ++#define LEN_LOW_SYMBOLS (1 << LEN_LOW_BITS) 1.3558 ++#define LEN_MID_BITS 3 1.3559 ++#define LEN_MID_SYMBOLS (1 << LEN_MID_BITS) 1.3560 ++#define LEN_HIGH_BITS 8 1.3561 ++#define LEN_HIGH_SYMBOLS (1 << LEN_HIGH_BITS) 1.3562 ++#define LEN_SYMBOLS (LEN_LOW_SYMBOLS + LEN_MID_SYMBOLS + LEN_HIGH_SYMBOLS) 1.3563 ++ 1.3564 ++/* 1.3565 ++ * Maximum length of a match is 273 which is a result of the encoding 1.3566 ++ * described above. 1.3567 ++ */ 1.3568 ++#define MATCH_LEN_MAX (MATCH_LEN_MIN + LEN_SYMBOLS - 1) 1.3569 ++ 1.3570 ++/* 1.3571 ++ * Different sets of probabilities are used for match distances that have 1.3572 ++ * very short match length: Lengths of 2, 3, and 4 bytes have a separate 1.3573 ++ * set of probabilities for each length. The matches with longer length 1.3574 ++ * use a shared set of probabilities. 1.3575 ++ */ 1.3576 ++#define DIST_STATES 4 1.3577 ++ 1.3578 ++/* 1.3579 ++ * Get the index of the appropriate probability array for decoding 1.3580 ++ * the distance slot. 1.3581 ++ */ 1.3582 ++static inline uint32_t lzma_get_dist_state(uint32_t len) 1.3583 ++{ 1.3584 ++ return len < DIST_STATES + MATCH_LEN_MIN 1.3585 ++ ? len - MATCH_LEN_MIN : DIST_STATES - 1; 1.3586 ++} 1.3587 ++ 1.3588 ++/* 1.3589 ++ * The highest two bits of a 32-bit match distance are encoded using six bits. 1.3590 ++ * This six-bit value is called a distance slot. This way encoding a 32-bit 1.3591 ++ * value takes 6-36 bits, larger values taking more bits. 1.3592 ++ */ 1.3593 ++#define DIST_SLOT_BITS 6 1.3594 ++#define DIST_SLOTS (1 << DIST_SLOT_BITS) 1.3595 ++ 1.3596 ++/* Match distances up to 127 are fully encoded using probabilities. Since 1.3597 ++ * the highest two bits (distance slot) are always encoded using six bits, 1.3598 ++ * the distances 0-3 don't need any additional bits to encode, since the 1.3599 ++ * distance slot itself is the same as the actual distance. DIST_MODEL_START 1.3600 ++ * indicates the first distance slot where at least one additional bit is 1.3601 ++ * needed. 1.3602 ++ */ 1.3603 ++#define DIST_MODEL_START 4 1.3604 ++ 1.3605 ++/* 1.3606 ++ * Match distances greater than 127 are encoded in three pieces: 1.3607 ++ * - distance slot: the highest two bits 1.3608 ++ * - direct bits: 2-26 bits below the highest two bits 1.3609 ++ * - alignment bits: four lowest bits 1.3610 ++ * 1.3611 ++ * Direct bits don't use any probabilities. 1.3612 ++ * 1.3613 ++ * The distance slot value of 14 is for distances 128-191. 1.3614 ++ */ 1.3615 ++#define DIST_MODEL_END 14 1.3616 ++ 1.3617 ++/* Distance slots that indicate a distance <= 127. */ 1.3618 ++#define FULL_DISTANCES_BITS (DIST_MODEL_END / 2) 1.3619 ++#define FULL_DISTANCES (1 << FULL_DISTANCES_BITS) 1.3620 ++ 1.3621 ++/* 1.3622 ++ * For match distances greater than 127, only the highest two bits and the 1.3623 ++ * lowest four bits (alignment) is encoded using probabilities. 1.3624 ++ */ 1.3625 ++#define ALIGN_BITS 4 1.3626 ++#define ALIGN_SIZE (1 << ALIGN_BITS) 1.3627 ++#define ALIGN_MASK (ALIGN_SIZE - 1) 1.3628 ++ 1.3629 ++/* Total number of all probability variables */ 1.3630 ++#define PROBS_TOTAL (1846 + LITERAL_CODERS_MAX * LITERAL_CODER_SIZE) 1.3631 ++ 1.3632 ++/* 1.3633 ++ * LZMA remembers the four most recent match distances. Reusing these 1.3634 ++ * distances tends to take less space than re-encoding the actual 1.3635 ++ * distance value. 1.3636 ++ */ 1.3637 ++#define REPS 4 1.3638 ++ 1.3639 ++#endif 1.3640 +diff --git a/lib/xz/xz_private.h b/lib/xz/xz_private.h 1.3641 +new file mode 100644 1.3642 +index 0000000..a65633e 1.3643 +--- /dev/null 1.3644 ++++ b/lib/xz/xz_private.h 1.3645 +@@ -0,0 +1,156 @@ 1.3646 ++/* 1.3647 ++ * Private includes and definitions 1.3648 ++ * 1.3649 ++ * Author: Lasse Collin <lasse.collin@tukaani.org> 1.3650 ++ * 1.3651 ++ * This file has been put into the public domain. 1.3652 ++ * You can do whatever you want with this file. 1.3653 ++ */ 1.3654 ++ 1.3655 ++#ifndef XZ_PRIVATE_H 1.3656 ++#define XZ_PRIVATE_H 1.3657 ++ 1.3658 ++#ifdef __KERNEL__ 1.3659 ++# include <linux/xz.h> 1.3660 ++# include <asm/byteorder.h> 1.3661 ++# include <asm/unaligned.h> 1.3662 ++ /* XZ_PREBOOT may be defined only via decompress_unxz.c. */ 1.3663 ++# ifndef XZ_PREBOOT 1.3664 ++# include <linux/slab.h> 1.3665 ++# include <linux/vmalloc.h> 1.3666 ++# include <linux/string.h> 1.3667 ++# ifdef CONFIG_XZ_DEC_X86 1.3668 ++# define XZ_DEC_X86 1.3669 ++# endif 1.3670 ++# ifdef CONFIG_XZ_DEC_POWERPC 1.3671 ++# define XZ_DEC_POWERPC 1.3672 ++# endif 1.3673 ++# ifdef CONFIG_XZ_DEC_IA64 1.3674 ++# define XZ_DEC_IA64 1.3675 ++# endif 1.3676 ++# ifdef CONFIG_XZ_DEC_ARM 1.3677 ++# define XZ_DEC_ARM 1.3678 ++# endif 1.3679 ++# ifdef CONFIG_XZ_DEC_ARMTHUMB 1.3680 ++# define XZ_DEC_ARMTHUMB 1.3681 ++# endif 1.3682 ++# ifdef CONFIG_XZ_DEC_SPARC 1.3683 ++# define XZ_DEC_SPARC 1.3684 ++# endif 1.3685 ++# define memeq(a, b, size) (memcmp(a, b, size) == 0) 1.3686 ++# define memzero(buf, size) memset(buf, 0, size) 1.3687 ++# endif 1.3688 ++# define get_le32(p) le32_to_cpup((const uint32_t *)(p)) 1.3689 ++#else 1.3690 ++ /* 1.3691 ++ * For userspace builds, use a separate header to define the required 1.3692 ++ * macros and functions. This makes it easier to adapt the code into 1.3693 ++ * different environments and avoids clutter in the Linux kernel tree. 1.3694 ++ */ 1.3695 ++# include "xz_config.h" 1.3696 ++#endif 1.3697 ++ 1.3698 ++/* If no specific decoding mode is requested, enable support for all modes. */ 1.3699 ++#if !defined(XZ_DEC_SINGLE) && !defined(XZ_DEC_PREALLOC) \ 1.3700 ++ && !defined(XZ_DEC_DYNALLOC) 1.3701 ++# define XZ_DEC_SINGLE 1.3702 ++# define XZ_DEC_PREALLOC 1.3703 ++# define XZ_DEC_DYNALLOC 1.3704 ++#endif 1.3705 ++ 1.3706 ++/* 1.3707 ++ * The DEC_IS_foo(mode) macros are used in "if" statements. If only some 1.3708 ++ * of the supported modes are enabled, these macros will evaluate to true or 1.3709 ++ * false at compile time and thus allow the compiler to omit unneeded code. 1.3710 ++ */ 1.3711 ++#ifdef XZ_DEC_SINGLE 1.3712 ++# define DEC_IS_SINGLE(mode) ((mode) == XZ_SINGLE) 1.3713 ++#else 1.3714 ++# define DEC_IS_SINGLE(mode) (false) 1.3715 ++#endif 1.3716 ++ 1.3717 ++#ifdef XZ_DEC_PREALLOC 1.3718 ++# define DEC_IS_PREALLOC(mode) ((mode) == XZ_PREALLOC) 1.3719 ++#else 1.3720 ++# define DEC_IS_PREALLOC(mode) (false) 1.3721 ++#endif 1.3722 ++ 1.3723 ++#ifdef XZ_DEC_DYNALLOC 1.3724 ++# define DEC_IS_DYNALLOC(mode) ((mode) == XZ_DYNALLOC) 1.3725 ++#else 1.3726 ++# define DEC_IS_DYNALLOC(mode) (false) 1.3727 ++#endif 1.3728 ++ 1.3729 ++#if !defined(XZ_DEC_SINGLE) 1.3730 ++# define DEC_IS_MULTI(mode) (true) 1.3731 ++#elif defined(XZ_DEC_PREALLOC) || defined(XZ_DEC_DYNALLOC) 1.3732 ++# define DEC_IS_MULTI(mode) ((mode) != XZ_SINGLE) 1.3733 ++#else 1.3734 ++# define DEC_IS_MULTI(mode) (false) 1.3735 ++#endif 1.3736 ++ 1.3737 ++/* 1.3738 ++ * If any of the BCJ filter decoders are wanted, define XZ_DEC_BCJ. 1.3739 ++ * XZ_DEC_BCJ is used to enable generic support for BCJ decoders. 1.3740 ++ */ 1.3741 ++#ifndef XZ_DEC_BCJ 1.3742 ++# if defined(XZ_DEC_X86) || defined(XZ_DEC_POWERPC) \ 1.3743 ++ || defined(XZ_DEC_IA64) || defined(XZ_DEC_ARM) \ 1.3744 ++ || defined(XZ_DEC_ARM) || defined(XZ_DEC_ARMTHUMB) \ 1.3745 ++ || defined(XZ_DEC_SPARC) 1.3746 ++# define XZ_DEC_BCJ 1.3747 ++# endif 1.3748 ++#endif 1.3749 ++ 1.3750 ++/* 1.3751 ++ * Allocate memory for LZMA2 decoder. xz_dec_lzma2_reset() must be used 1.3752 ++ * before calling xz_dec_lzma2_run(). 1.3753 ++ */ 1.3754 ++XZ_EXTERN struct xz_dec_lzma2 *xz_dec_lzma2_create(enum xz_mode mode, 1.3755 ++ uint32_t dict_max); 1.3756 ++ 1.3757 ++/* 1.3758 ++ * Decode the LZMA2 properties (one byte) and reset the decoder. Return 1.3759 ++ * XZ_OK on success, XZ_MEMLIMIT_ERROR if the preallocated dictionary is not 1.3760 ++ * big enough, and XZ_OPTIONS_ERROR if props indicates something that this 1.3761 ++ * decoder doesn't support. 1.3762 ++ */ 1.3763 ++XZ_EXTERN enum xz_ret xz_dec_lzma2_reset(struct xz_dec_lzma2 *s, 1.3764 ++ uint8_t props); 1.3765 ++ 1.3766 ++/* Decode raw LZMA2 stream from b->in to b->out. */ 1.3767 ++XZ_EXTERN enum xz_ret xz_dec_lzma2_run(struct xz_dec_lzma2 *s, 1.3768 ++ struct xz_buf *b); 1.3769 ++ 1.3770 ++/* Free the memory allocated for the LZMA2 decoder. */ 1.3771 ++XZ_EXTERN void xz_dec_lzma2_end(struct xz_dec_lzma2 *s); 1.3772 ++ 1.3773 ++#ifdef XZ_DEC_BCJ 1.3774 ++/* 1.3775 ++ * Allocate memory for BCJ decoders. xz_dec_bcj_reset() must be used before 1.3776 ++ * calling xz_dec_bcj_run(). 1.3777 ++ */ 1.3778 ++XZ_EXTERN struct xz_dec_bcj *xz_dec_bcj_create(bool single_call); 1.3779 ++ 1.3780 ++/* 1.3781 ++ * Decode the Filter ID of a BCJ filter. This implementation doesn't 1.3782 ++ * support custom start offsets, so no decoding of Filter Properties 1.3783 ++ * is needed. Returns XZ_OK if the given Filter ID is supported. 1.3784 ++ * Otherwise XZ_OPTIONS_ERROR is returned. 1.3785 ++ */ 1.3786 ++XZ_EXTERN enum xz_ret xz_dec_bcj_reset(struct xz_dec_bcj *s, uint8_t id); 1.3787 ++ 1.3788 ++/* 1.3789 ++ * Decode raw BCJ + LZMA2 stream. This must be used only if there actually is 1.3790 ++ * a BCJ filter in the chain. If the chain has only LZMA2, xz_dec_lzma2_run() 1.3791 ++ * must be called directly. 1.3792 ++ */ 1.3793 ++XZ_EXTERN enum xz_ret xz_dec_bcj_run(struct xz_dec_bcj *s, 1.3794 ++ struct xz_dec_lzma2 *lzma2, 1.3795 ++ struct xz_buf *b); 1.3796 ++ 1.3797 ++/* Free the memory allocated for the BCJ filters. */ 1.3798 ++#define xz_dec_bcj_end(s) kfree(s) 1.3799 ++#endif 1.3800 ++ 1.3801 ++#endif 1.3802 +diff --git a/lib/xz/xz_stream.h b/lib/xz/xz_stream.h 1.3803 +new file mode 100644 1.3804 +index 0000000..66cb5a7 1.3805 +--- /dev/null 1.3806 ++++ b/lib/xz/xz_stream.h 1.3807 +@@ -0,0 +1,62 @@ 1.3808 ++/* 1.3809 ++ * Definitions for handling the .xz file format 1.3810 ++ * 1.3811 ++ * Author: Lasse Collin <lasse.collin@tukaani.org> 1.3812 ++ * 1.3813 ++ * This file has been put into the public domain. 1.3814 ++ * You can do whatever you want with this file. 1.3815 ++ */ 1.3816 ++ 1.3817 ++#ifndef XZ_STREAM_H 1.3818 ++#define XZ_STREAM_H 1.3819 ++ 1.3820 ++#if defined(__KERNEL__) && !XZ_INTERNAL_CRC32 1.3821 ++# include <linux/crc32.h> 1.3822 ++# undef crc32 1.3823 ++# define xz_crc32(buf, size, crc) \ 1.3824 ++ (~crc32_le(~(uint32_t)(crc), buf, size)) 1.3825 ++#endif 1.3826 ++ 1.3827 ++/* 1.3828 ++ * See the .xz file format specification at 1.3829 ++ * http://tukaani.org/xz/xz-file-format.txt 1.3830 ++ * to understand the container format. 1.3831 ++ */ 1.3832 ++ 1.3833 ++#define STREAM_HEADER_SIZE 12 1.3834 ++ 1.3835 ++#define HEADER_MAGIC "\3757zXZ" 1.3836 ++#define HEADER_MAGIC_SIZE 6 1.3837 ++ 1.3838 ++#define FOOTER_MAGIC "YZ" 1.3839 ++#define FOOTER_MAGIC_SIZE 2 1.3840 ++ 1.3841 ++/* 1.3842 ++ * Variable-length integer can hold a 63-bit unsigned integer or a special 1.3843 ++ * value indicating that the value is unknown. 1.3844 ++ * 1.3845 ++ * Experimental: vli_type can be defined to uint32_t to save a few bytes 1.3846 ++ * in code size (no effect on speed). Doing so limits the uncompressed and 1.3847 ++ * compressed size of the file to less than 256 MiB and may also weaken 1.3848 ++ * error detection slightly. 1.3849 ++ */ 1.3850 ++typedef uint64_t vli_type; 1.3851 ++ 1.3852 ++#define VLI_MAX ((vli_type)-1 / 2) 1.3853 ++#define VLI_UNKNOWN ((vli_type)-1) 1.3854 ++ 1.3855 ++/* Maximum encoded size of a VLI */ 1.3856 ++#define VLI_BYTES_MAX (sizeof(vli_type) * 8 / 7) 1.3857 ++ 1.3858 ++/* Integrity Check types */ 1.3859 ++enum xz_check { 1.3860 ++ XZ_CHECK_NONE = 0, 1.3861 ++ XZ_CHECK_CRC32 = 1, 1.3862 ++ XZ_CHECK_CRC64 = 4, 1.3863 ++ XZ_CHECK_SHA256 = 10 1.3864 ++}; 1.3865 ++ 1.3866 ++/* Maximum possible Check ID */ 1.3867 ++#define XZ_CHECK_MAX 15 1.3868 ++ 1.3869 ++#endif 1.3870 +diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib 1.3871 +index 54fd1b7..b862007 100644 1.3872 +--- a/scripts/Makefile.lib 1.3873 ++++ b/scripts/Makefile.lib 1.3874 +@@ -246,6 +246,34 @@ cmd_lzo = (cat $(filter-out FORCE,$^) | \ 1.3875 + lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 1.3876 + (rm -f $@ ; false) 1.3877 + 1.3878 ++# XZ 1.3879 ++# --------------------------------------------------------------------------- 1.3880 ++# Use xzkern to compress the kernel image and xzmisc to compress other things. 1.3881 ++# 1.3882 ++# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage 1.3883 ++# of the kernel decompressor. A BCJ filter is used if it is available for 1.3884 ++# the target architecture. xzkern also appends uncompressed size of the data 1.3885 ++# using size_append. The .xz format has the size information available at 1.3886 ++# the end of the file too, but it's in more complex format and it's good to 1.3887 ++# avoid changing the part of the boot code that reads the uncompressed size. 1.3888 ++# Note that the bytes added by size_append will make the xz tool think that 1.3889 ++# the file is corrupt. This is expected. 1.3890 ++# 1.3891 ++# xzmisc doesn't use size_append, so it can be used to create normal .xz 1.3892 ++# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very 1.3893 ++# big dictionary would increase the memory usage too much in the multi-call 1.3894 ++# decompression mode. A BCJ filter isn't used either. 1.3895 ++quiet_cmd_xzkern = XZKERN $@ 1.3896 ++cmd_xzkern = (cat $(filter-out FORCE,$^) | \ 1.3897 ++ sh $(srctree)/scripts/xz_wrap.sh && \ 1.3898 ++ $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 1.3899 ++ (rm -f $@ ; false) 1.3900 ++ 1.3901 ++quiet_cmd_xzmisc = XZMISC $@ 1.3902 ++cmd_xzmisc = (cat $(filter-out FORCE,$^) | \ 1.3903 ++ xz --check=crc32 --lzma2=dict=1MiB) > $@ || \ 1.3904 ++ (rm -f $@ ; false) 1.3905 ++ 1.3906 + # misc stuff 1.3907 + # --------------------------------------------------------------------------- 1.3908 + quote:=" 1.3909 +diff --git a/scripts/xz_wrap.sh b/scripts/xz_wrap.sh 1.3910 +new file mode 100644 1.3911 +index 0000000..17a5798 1.3912 +--- /dev/null 1.3913 ++++ b/scripts/xz_wrap.sh 1.3914 +@@ -0,0 +1,23 @@ 1.3915 ++#!/bin/sh 1.3916 ++# 1.3917 ++# This is a wrapper for xz to compress the kernel image using appropriate 1.3918 ++# compression options depending on the architecture. 1.3919 ++# 1.3920 ++# Author: Lasse Collin <lasse.collin@tukaani.org> 1.3921 ++# 1.3922 ++# This file has been put into the public domain. 1.3923 ++# You can do whatever you want with this file. 1.3924 ++# 1.3925 ++ 1.3926 ++BCJ= 1.3927 ++LZMA2OPTS= 1.3928 ++ 1.3929 ++case $ARCH in 1.3930 ++ x86|x86_64) BCJ=--x86 ;; 1.3931 ++ powerpc) BCJ=--powerpc ;; 1.3932 ++ ia64) BCJ=--ia64; LZMA2OPTS=pb=4 ;; 1.3933 ++ arm) BCJ=--arm ;; 1.3934 ++ sparc) BCJ=--sparc ;; 1.3935 ++esac 1.3936 ++ 1.3937 ++exec xz --check=crc32 $BCJ --lzma2=$LZMA2OPTS,dict=32MiB