From 716f3f612e62c55edd052b505a86e4e2e09074a5 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Tue, 1 Jun 2010 14:41:39 +0200 Subject: [PATCH] decompress_unxz: newer version, one which can unpack SHA-256 protected files function old new delta check_sizes - 16 +16 crc32_table - 4 +4 index_update 47 40 -7 crc32_validate 110 93 -17 dec_vli 197 165 -32 unpack_xz_stream 4284 4014 -270 ------------------------------------------------------------------------------ (add/remove: 2/0 grow/shrink: 0/4 up/down: 20/-326) Total: -306 bytes Signed-off-by: Denys Vlasenko --- archival/libunarchive/decompress_unxz.c | 18 +++-- archival/libunarchive/unxz/xz.h | 58 +++++++++------ archival/libunarchive/unxz/xz_config.h | 6 +- archival/libunarchive/unxz/xz_dec_bcj.c | 10 ++- archival/libunarchive/unxz/xz_dec_stream.c | 113 +++++++++++++++++++++-------- archival/libunarchive/unxz/xz_private.h | 2 +- archival/libunarchive/unxz/xz_stream.h | 15 +++- 7 files changed, 154 insertions(+), 68 deletions(-) diff --git a/archival/libunarchive/decompress_unxz.c b/archival/libunarchive/decompress_unxz.c index 924a525..374b76d 100644 --- a/archival/libunarchive/decompress_unxz.c +++ b/archival/libunarchive/decompress_unxz.c @@ -16,9 +16,13 @@ #define XZ_FUNC FAST_FUNC #define XZ_EXTERN static -#define xz_crc32_init(table) crc32_filltable(table, /*endian:*/ 0) -static uint32_t xz_crc32(uint32_t *crc32_table, - const uint8_t *buf, size_t size, uint32_t crc) +/* Skip check (rather than fail) of unsupported hash functions */ +#define XZ_DEC_ANY_CHECK 1 + +/* We use our own crc32 function */ +#define XZ_INTERNAL_CRC32 0 +static uint32_t *crc32_table; +static uint32_t xz_crc32(const uint8_t *buf, size_t size, uint32_t crc) { crc = ~crc; @@ -29,8 +33,8 @@ static uint32_t xz_crc32(uint32_t *crc32_table, return ~crc; } -#define xz_crc32 xz_crc32 +/* We use arch-optimized unaligned accessors */ #define get_unaligned_le32(buf) ({ uint32_t v; move_from_unaligned32(v, buf); SWAP_LE32(v); }) #define get_unaligned_be32(buf) ({ uint32_t v; move_from_unaligned32(v, buf); SWAP_BE32(v); }) #define put_unaligned_le32(val, buf) move_to_unaligned16(buf, SWAP_LE32(val)) @@ -64,8 +68,10 @@ unpack_xz_stream(int src_fd, int dst_fd) iobuf.out = membuf + IN_SIZE; iobuf.out_size = OUT_SIZE; + if (!crc32_table) + crc32_table = crc32_filltable(NULL, /*endian:*/ 0); + state = xz_dec_init(64*1024); /* initial dict of 64k */ - xz_crc32_init(state->crc32_table); while (1) { enum xz_ret r; @@ -102,7 +108,7 @@ unpack_xz_stream(int src_fd, int dst_fd) ) { break; } - if (r != XZ_OK) { + if (r != XZ_OK && r != XZ_UNSUPPORTED_CHECK) { bb_error_msg("corrupted data"); total = -1; break; diff --git a/archival/libunarchive/unxz/xz.h b/archival/libunarchive/unxz/xz.h index dbb9ba9..eb82706 100644 --- a/archival/libunarchive/unxz/xz.h +++ b/archival/libunarchive/unxz/xz.h @@ -31,20 +31,29 @@ /** * enum xz_ret - Return codes - * @XZ_OK: Everything is OK so far. More input or more output - * space is required to continue. - * @XZ_STREAM_END: Operation finished successfully. - * @XZ_MEMLIMIT_ERROR: Not enough memory was preallocated at decoder - * initialization time. - * @XZ_FORMAT_ERROR: File format was not recognized (wrong magic bytes). - * @XZ_OPTIONS_ERROR: This implementation doesn't support the requested - * compression options. In the decoder this means that - * the header CRC32 matches, but the header itself - * specifies something that we don't support. - * @XZ_DATA_ERROR: Compressed data is corrupt. - * @XZ_BUF_ERROR: Cannot make any progress. Details are slightly - * different between multi-call and single-call mode; - * more information below. + * @XZ_OK: Everything is OK so far. More input or more + * output space is required to continue. + * @XZ_STREAM_END: Operation finished successfully. + * @XZ_UNSUPPORTED_CHECK: Integrity check type is not supported. Decoding + * is still possible in multi-call mode by simply + * calling xz_dec_run() again. + * NOTE: This return value is used only if + * XZ_DEC_ANY_CHECK was defined at build time, + * which is not used in the kernel. Unsupported + * check types return XZ_OPTIONS_ERROR if + * XZ_DEC_ANY_CHECK was not defined at build time. + * @XZ_MEMLIMIT_ERROR: Not enough memory was preallocated at decoder + * initialization time. + * @XZ_FORMAT_ERROR: File format was not recognized (wrong magic + * bytes). + * @XZ_OPTIONS_ERROR: This implementation doesn't support the requested + * compression options. In the decoder this means + * that the header CRC32 matches, but the header + * itself specifies something that we don't support. + * @XZ_DATA_ERROR: Compressed data is corrupt. + * @XZ_BUF_ERROR: Cannot make any progress. Details are slightly + * different between multi-call and single-call + * mode; more information below. * * In multi-call mode, XZ_BUF_ERROR is returned when two consecutive calls * to XZ code cannot consume any input and cannot produce any new output. @@ -62,6 +71,7 @@ enum xz_ret { XZ_OK, XZ_STREAM_END, + XZ_UNSUPPORTED_CHECK, XZ_MEMLIMIT_ERROR, XZ_FORMAT_ERROR, XZ_OPTIONS_ERROR, @@ -129,7 +139,7 @@ struct xz_dec; * * Because the output buffer is used as the workspace, streams encoded using * a big dictionary are not a problem in single-call. It is enough that the - * output buffer is is big enough to hold the actual uncompressed data; it + * output buffer is big enough to hold the actual uncompressed data; it * can be smaller than the dictionary size stored in the stream headers. * * On success, xz_dec_init() returns a pointer to struct xz_dec, which is @@ -186,23 +196,27 @@ XZ_EXTERN void XZ_FUNC xz_dec_end(struct xz_dec *s); * CRC32 module is used instead, and users of this module don't need to * care about the functions below. */ -#if !defined(__KERNEL__) || defined(XZ_INTERNAL_CRC32) +#ifndef XZ_INTERNAL_CRC32 +# ifdef __KERNEL__ +# define XZ_INTERNAL_CRC32 0 +# else +# define XZ_INTERNAL_CRC32 1 +# endif +#endif + +#if XZ_INTERNAL_CRC32 /* * This must be called before any other xz_* function to initialize * the CRC32 lookup table. */ -#ifndef xz_crc32_init -XZ_EXTERN void XZ_FUNC xz_crc32_init(uint32_t *crc32_table); -#endif +XZ_EXTERN void XZ_FUNC xz_crc32_init(void); /* * Update CRC32 value using the polynomial from IEEE-802.3. To start a new * calculation, the third argument must be zero. To continue the calculation, * the previously returned value is passed as the third argument. */ -#ifndef xz_crc32 -XZ_EXTERN uint32_t XZ_FUNC xz_crc32(uint32_t *crc32_table, +XZ_EXTERN uint32_t XZ_FUNC xz_crc32( const uint8_t *buf, size_t size, uint32_t crc); #endif #endif -#endif diff --git a/archival/libunarchive/unxz/xz_config.h b/archival/libunarchive/unxz/xz_config.h index 3259815..ff90eff 100644 --- a/archival/libunarchive/unxz/xz_config.h +++ b/archival/libunarchive/unxz/xz_config.h @@ -43,7 +43,7 @@ * becomes slow. * * NOTE: System headers on GNU/Linux may #define this macro already, - * so if you want to change it, it you need to #undef it first. + * so if you want to change it, you need to #undef it first. */ #ifndef __always_inline # ifdef __GNUC__ @@ -114,6 +114,8 @@ static inline void XZ_FUNC put_unaligned_be32(uint32_t val, uint8_t *buf) * little endian systems, #define get_le32(ptr) (*(const uint32_t *)(ptr)) * could save a few bytes in code size. */ -#define get_le32 get_unaligned_le32 +#ifndef get_le32 +# define get_le32 get_unaligned_le32 +#endif #endif diff --git a/archival/libunarchive/unxz/xz_dec_bcj.c b/archival/libunarchive/unxz/xz_dec_bcj.c index d4b6ef7..09162b5 100644 --- a/archival/libunarchive/unxz/xz_dec_bcj.c +++ b/archival/libunarchive/unxz/xz_dec_bcj.c @@ -10,6 +10,12 @@ #include "xz_private.h" +/* + * The rest of the file is inside this ifdef. It makes things a little more + * convenient when building without support for any BCJ filters. + */ +#ifdef XZ_DEC_BCJ + struct xz_dec_bcj { /* Type of the BCJ filter being used */ enum { @@ -331,7 +337,6 @@ static noinline_for_stack size_t XZ_FUNC bcj_sparc( } #endif -#ifdef XZ_DEC_BCJ /* * Apply the selected BCJ filter. Update *pos and s->pos to match the amount * of data that got filtered. @@ -388,9 +393,7 @@ static void XZ_FUNC bcj_apply(struct xz_dec_bcj *s, *pos += filtered; s->pos += filtered; } -#endif -#ifdef XZ_DEC_BCJ /* * Flush pending filtered data from temp to the output buffer. * Move the remaining mixture of possibly filtered and unfiltered @@ -557,4 +560,5 @@ XZ_EXTERN enum xz_ret XZ_FUNC xz_dec_bcj_reset( return XZ_OK; } + #endif diff --git a/archival/libunarchive/unxz/xz_dec_stream.c b/archival/libunarchive/unxz/xz_dec_stream.c index 121c3b5..21db283 100644 --- a/archival/libunarchive/unxz/xz_dec_stream.c +++ b/archival/libunarchive/unxz/xz_dec_stream.c @@ -45,8 +45,8 @@ struct xz_dec { /* CRC32 value in Block or Index */ uint32_t crc32; - /* True if CRC32 is calculated from uncompressed data */ - uint8_t crc_type; + /* Type of the integrity check calculated from uncompressed data */ + enum xz_check check_type; /* True if we are operating in single-call mode. */ bool single_call; @@ -134,9 +134,19 @@ struct xz_dec { struct xz_dec_bcj *bcj; bool bcj_active; #endif +}; - uint32_t crc32_table[256]; +#ifdef XZ_DEC_ANY_CHECK +/* Sizes of the Check field with different Check IDs */ +static const uint8_t check_sizes[16] = { + 0, + 4, 4, 4, + 8, 8, 8, + 16, 16, 16, + 32, 32, 32, + 64, 64, 64 }; +#endif /* * Fill s->temp by copying data starting from b->in[b->in_pos]. Caller @@ -231,9 +241,8 @@ static enum xz_ret XZ_FUNC dec_block(struct xz_dec *s, struct xz_buf *b) > s->block_header.uncompressed) return XZ_DATA_ERROR; - if (s->crc_type == 0x01) - s->crc32 = xz_crc32(s->crc32_table, - b->out + s->out_start, + if (s->check_type == XZ_CHECK_CRC32) + s->crc32 = xz_crc32(b->out + s->out_start, b->out_pos - s->out_start, s->crc32); if (ret == XZ_STREAM_END) { @@ -249,15 +258,16 @@ static enum xz_ret XZ_FUNC dec_block(struct xz_dec *s, struct xz_buf *b) s->block.hash.unpadded += s->block_header.size + s->block.compressed; - if (s->crc_type == 0x01) + +#ifdef XZ_DEC_ANY_CHECK + s->block.hash.unpadded += check_sizes[s->check_type]; +#else + if (s->check_type == XZ_CHECK_CRC32) s->block.hash.unpadded += 4; - if (s->crc_type == 0x04) /* CRC64 */ - s->block.hash.unpadded += 8; - if (s->crc_type == 0x0A) /* SHA-256 */ - s->block.hash.unpadded += 32; +#endif s->block.hash.uncompressed += s->block.uncompressed; - s->block.hash.crc32 = xz_crc32(s->crc32_table, + s->block.hash.crc32 = xz_crc32( (const uint8_t *)&s->block.hash, sizeof(s->block.hash), s->block.hash.crc32); @@ -272,7 +282,7 @@ static void XZ_FUNC index_update(struct xz_dec *s, const struct xz_buf *b) { size_t in_used = b->in_pos - s->in_start; s->index.size += in_used; - s->crc32 = xz_crc32(s->crc32_table, b->in + s->in_start, in_used, s->crc32); + s->crc32 = xz_crc32(b->in + s->in_start, in_used, s->crc32); } /* @@ -316,7 +326,7 @@ static enum xz_ret XZ_FUNC dec_index(struct xz_dec *s, struct xz_buf *b) case SEQ_INDEX_UNCOMPRESSED: s->index.hash.uncompressed += s->vli; - s->index.hash.crc32 = xz_crc32(s->crc32_table, + s->index.hash.crc32 = xz_crc32( (const uint8_t *)&s->index.hash, sizeof(s->index.hash), s->index.hash.crc32); @@ -352,31 +362,58 @@ static enum xz_ret XZ_FUNC crc32_validate(struct xz_dec *s, struct xz_buf *b) return XZ_STREAM_END; } +#ifdef XZ_DEC_ANY_CHECK +/* + * Skip over the Check field when the Check ID is not supported. + * Returns true once the whole Check field has been skipped over. + */ +static bool XZ_FUNC check_skip(struct xz_dec *s, struct xz_buf *b) +{ + while (s->pos < check_sizes[s->check_type]) { + if (b->in_pos == b->in_size) + return false; + + ++b->in_pos; + ++s->pos; + } + + s->pos = 0; + + return true; +} +#endif + /* Decode the Stream Header field (the first 12 bytes of the .xz Stream). */ static enum xz_ret XZ_FUNC dec_stream_header(struct xz_dec *s) { if (!memeq(s->temp.buf, HEADER_MAGIC, HEADER_MAGIC_SIZE)) return XZ_FORMAT_ERROR; - if (xz_crc32(s->crc32_table, s->temp.buf + HEADER_MAGIC_SIZE, 2, 0) + if (xz_crc32(s->temp.buf + HEADER_MAGIC_SIZE, 2, 0) != get_le32(s->temp.buf + HEADER_MAGIC_SIZE + 2)) return XZ_DATA_ERROR; + if (s->temp.buf[HEADER_MAGIC_SIZE] != 0) + return XZ_OPTIONS_ERROR; + /* - * Decode the Stream Flags field. Of integrity checks, we support - * only none (Check ID = 0) and CRC32 (Check ID = 1). - * We also accept CRC64 and SHA-256, but they will not be verified. + * Of integrity checks, we support only none (Check ID = 0) and + * CRC32 (Check ID = 1). However, if XZ_DEC_ANY_CHECK is defined, + * we will accept other check types too, but then the check won't + * be verified and a warning (XZ_UNSUPPORTED_CHECK) will be given. */ - if (s->temp.buf[HEADER_MAGIC_SIZE] != 0 - || (s->temp.buf[HEADER_MAGIC_SIZE + 1] > 1 - && s->temp.buf[HEADER_MAGIC_SIZE + 1] != 0x04 /* CRC64 */ - && s->temp.buf[HEADER_MAGIC_SIZE + 1] != 0x0A /* SHA-256 */ - ) - ) { + s->check_type = s->temp.buf[HEADER_MAGIC_SIZE + 1]; + +#ifdef XZ_DEC_ANY_CHECK + if (s->check_type > XZ_CHECK_MAX) return XZ_OPTIONS_ERROR; - } - s->crc_type = s->temp.buf[HEADER_MAGIC_SIZE + 1]; + if (s->check_type > XZ_CHECK_CRC32) + return XZ_UNSUPPORTED_CHECK; +#else + if (s->check_type > XZ_CHECK_CRC32) + return XZ_OPTIONS_ERROR; +#endif return XZ_OK; } @@ -387,7 +424,7 @@ static enum xz_ret XZ_FUNC dec_stream_footer(struct xz_dec *s) if (!memeq(s->temp.buf + 10, FOOTER_MAGIC, FOOTER_MAGIC_SIZE)) return XZ_DATA_ERROR; - if (xz_crc32(s->crc32_table, s->temp.buf + 4, 6, 0) != get_le32(s->temp.buf)) + if (xz_crc32(s->temp.buf + 4, 6, 0) != get_le32(s->temp.buf)) return XZ_DATA_ERROR; /* @@ -398,7 +435,7 @@ static enum xz_ret XZ_FUNC dec_stream_footer(struct xz_dec *s) if ((s->index.size >> 2) != get_le32(s->temp.buf + 4)) return XZ_DATA_ERROR; - if (s->temp.buf[8] != 0 || s->temp.buf[9] != s->crc_type) + if (s->temp.buf[8] != 0 || s->temp.buf[9] != s->check_type) return XZ_DATA_ERROR; /* @@ -418,7 +455,7 @@ static enum xz_ret XZ_FUNC dec_block_header(struct xz_dec *s) * eight bytes so this is safe. */ s->temp.size -= 4; - if (xz_crc32(s->crc32_table, s->temp.buf, s->temp.size, 0) + if (xz_crc32(s->temp.buf, s->temp.size, 0) != get_le32(s->temp.buf + s->temp.size)) return XZ_DATA_ERROR; @@ -533,12 +570,19 @@ static enum xz_ret XZ_FUNC dec_main(struct xz_dec *s, struct xz_buf *b) if (!fill_temp(s, b)) return XZ_OK; + /* + * If dec_stream_header() returns + * XZ_UNSUPPORTED_CHECK, it is still possible + * to continue decoding if working in multi-call + * mode. Thus, update s->sequence before calling + * dec_stream_header(). + */ + s->sequence = SEQ_BLOCK_START; + ret = dec_stream_header(s); if (ret != XZ_OK) return ret; - s->sequence = SEQ_BLOCK_START; - case SEQ_BLOCK_START: /* We need one byte of input to continue. */ if (b->in_pos == b->in_size) @@ -600,11 +644,16 @@ static enum xz_ret XZ_FUNC dec_main(struct xz_dec *s, struct xz_buf *b) s->sequence = SEQ_BLOCK_CHECK; case SEQ_BLOCK_CHECK: - if (s->crc_type == 0x01) { + if (s->check_type == XZ_CHECK_CRC32) { ret = crc32_validate(s, b); if (ret != XZ_STREAM_END) return ret; } +#ifdef XZ_DEC_ANY_CHECK + else if (!check_skip(s, b)) { + return XZ_OK; + } +#endif s->sequence = SEQ_BLOCK_START; break; diff --git a/archival/libunarchive/unxz/xz_private.h b/archival/libunarchive/unxz/xz_private.h index 9da8d70..f4e0b40 100644 --- a/archival/libunarchive/unxz/xz_private.h +++ b/archival/libunarchive/unxz/xz_private.h @@ -112,9 +112,9 @@ XZ_EXTERN enum xz_ret XZ_FUNC xz_dec_bcj_reset( */ XZ_EXTERN enum xz_ret XZ_FUNC xz_dec_bcj_run(struct xz_dec_bcj *s, struct xz_dec_lzma2 *lzma2, struct xz_buf *b); -#endif /* Free the memory allocated for the BCJ filters. */ #define xz_dec_bcj_end(s) kfree(s) +#endif #endif diff --git a/archival/libunarchive/unxz/xz_stream.h b/archival/libunarchive/unxz/xz_stream.h index efbe75a..36f2a7c 100644 --- a/archival/libunarchive/unxz/xz_stream.h +++ b/archival/libunarchive/unxz/xz_stream.h @@ -10,10 +10,10 @@ #ifndef XZ_STREAM_H #define XZ_STREAM_H -#if defined(__KERNEL__) && !defined(XZ_INTERNAL_CRC32) +#if defined(__KERNEL__) && !XZ_INTERNAL_CRC32 # include # undef crc32 -# define xz_crc32(crc32_table, buf, size, crc) \ +# define xz_crc32(buf, size, crc) \ (~crc32_le(~(uint32_t)(crc), buf, size)) #endif @@ -43,4 +43,15 @@ typedef uint64_t vli_type; /* Maximum encoded size of a VLI */ #define VLI_BYTES_MAX (sizeof(vli_type) * 8 / 7) +/* Integrity Check types */ +enum xz_check { + XZ_CHECK_NONE = 0, + XZ_CHECK_CRC32 = 1, + XZ_CHECK_CRC64 = 4, + XZ_CHECK_SHA256 = 10 +}; + +/* Maximum possible Check ID */ +#define XZ_CHECK_MAX 15 + #endif -- 2.7.4