^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) * .xz Stream decoder
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Author: Lasse Collin <lasse.collin@tukaani.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * This file has been put into the public domain.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * You can do whatever you want with this file.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include "xz_private.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include "xz_stream.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) /* Hash used to validate the Index field */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) struct xz_dec_hash {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) vli_type unpadded;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) vli_type uncompressed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) uint32_t crc32;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) struct xz_dec {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) /* Position in dec_main() */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) enum {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) SEQ_STREAM_HEADER,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) SEQ_BLOCK_START,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) SEQ_BLOCK_HEADER,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) SEQ_BLOCK_UNCOMPRESS,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) SEQ_BLOCK_PADDING,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) SEQ_BLOCK_CHECK,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) SEQ_INDEX,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) SEQ_INDEX_PADDING,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) SEQ_INDEX_CRC32,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) SEQ_STREAM_FOOTER
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) } sequence;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) /* Position in variable-length integers and Check fields */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) uint32_t pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) /* Variable-length integer decoded by dec_vli() */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) vli_type vli;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) /* Saved in_pos and out_pos */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) size_t in_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) size_t out_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) /* CRC32 value in Block or Index */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) uint32_t crc32;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) /* Type of the integrity check calculated from uncompressed data */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) enum xz_check check_type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) /* Operation mode */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) enum xz_mode mode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) * True if the next call to xz_dec_run() is allowed to return
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) * XZ_BUF_ERROR.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) bool allow_buf_error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) /* Information stored in Block Header */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) struct {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) * Value stored in the Compressed Size field, or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) * VLI_UNKNOWN if Compressed Size is not present.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) vli_type compressed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) * Value stored in the Uncompressed Size field, or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) * VLI_UNKNOWN if Uncompressed Size is not present.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) vli_type uncompressed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) /* Size of the Block Header field */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) uint32_t size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) } block_header;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) /* Information collected when decoding Blocks */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) struct {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) /* Observed compressed size of the current Block */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) vli_type compressed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) /* Observed uncompressed size of the current Block */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) vli_type uncompressed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) /* Number of Blocks decoded so far */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) vli_type count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) * Hash calculated from the Block sizes. This is used to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) * validate the Index field.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) struct xz_dec_hash hash;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) } block;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) /* Variables needed when verifying the Index field */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) struct {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) /* Position in dec_index() */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) enum {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) SEQ_INDEX_COUNT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) SEQ_INDEX_UNPADDED,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) SEQ_INDEX_UNCOMPRESSED
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) } sequence;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) /* Size of the Index in bytes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) vli_type size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) /* Number of Records (matches block.count in valid files) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) vli_type count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) * Hash calculated from the Records (matches block.hash in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) * valid files).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) struct xz_dec_hash hash;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) } index;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) * Temporary buffer needed to hold Stream Header, Block Header,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) * and Stream Footer. The Block Header is the biggest (1 KiB)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) * so we reserve space according to that. buf[] has to be aligned
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) * to a multiple of four bytes; the size_t variables before it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) * should guarantee this.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) struct {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) size_t pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) size_t size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) uint8_t buf[1024];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) } temp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) struct xz_dec_lzma2 *lzma2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) #ifdef XZ_DEC_BCJ
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) struct xz_dec_bcj *bcj;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) bool bcj_active;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) #ifdef XZ_DEC_ANY_CHECK
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) /* Sizes of the Check field with different Check IDs */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) static const uint8_t check_sizes[16] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 4, 4, 4,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 8, 8, 8,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 16, 16, 16,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 32, 32, 32,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 64, 64, 64
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) * Fill s->temp by copying data starting from b->in[b->in_pos]. Caller
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) * must have set s->temp.pos to indicate how much data we are supposed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) * to copy into s->temp.buf. Return true once s->temp.pos has reached
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) * s->temp.size.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) static bool fill_temp(struct xz_dec *s, struct xz_buf *b)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) size_t copy_size = min_t(size_t,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) b->in_size - b->in_pos, s->temp.size - s->temp.pos);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) memcpy(s->temp.buf + s->temp.pos, b->in + b->in_pos, copy_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) b->in_pos += copy_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) s->temp.pos += copy_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) if (s->temp.pos == s->temp.size) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) s->temp.pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) /* Decode a variable-length integer (little-endian base-128 encoding) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) static enum xz_ret dec_vli(struct xz_dec *s, const uint8_t *in,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) size_t *in_pos, size_t in_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) uint8_t byte;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) if (s->pos == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) s->vli = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) while (*in_pos < in_size) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) byte = in[*in_pos];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) ++*in_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) s->vli |= (vli_type)(byte & 0x7F) << s->pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) if ((byte & 0x80) == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) /* Don't allow non-minimal encodings. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) if (byte == 0 && s->pos != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) s->pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) return XZ_STREAM_END;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) s->pos += 7;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) if (s->pos == 7 * VLI_BYTES_MAX)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) * Decode the Compressed Data field from a Block. Update and validate
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) * the observed compressed and uncompressed sizes of the Block so that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) * they don't exceed the values possibly stored in the Block Header
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) * (validation assumes that no integer overflow occurs, since vli_type
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) * is normally uint64_t). Update the CRC32 if presence of the CRC32
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) * field was indicated in Stream Header.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) * Once the decoding is finished, validate that the observed sizes match
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) * the sizes possibly stored in the Block Header. Update the hash and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) * Block count, which are later used to validate the Index field.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) static enum xz_ret dec_block(struct xz_dec *s, struct xz_buf *b)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) enum xz_ret ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) s->in_start = b->in_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) s->out_start = b->out_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) #ifdef XZ_DEC_BCJ
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) if (s->bcj_active)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) ret = xz_dec_bcj_run(s->bcj, s->lzma2, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) ret = xz_dec_lzma2_run(s->lzma2, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) s->block.compressed += b->in_pos - s->in_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) s->block.uncompressed += b->out_pos - s->out_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) * There is no need to separately check for VLI_UNKNOWN, since
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) * the observed sizes are always smaller than VLI_UNKNOWN.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) if (s->block.compressed > s->block_header.compressed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) || s->block.uncompressed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) > s->block_header.uncompressed)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) if (s->check_type == XZ_CHECK_CRC32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) s->crc32 = xz_crc32(b->out + s->out_start,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) b->out_pos - s->out_start, s->crc32);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) if (ret == XZ_STREAM_END) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) if (s->block_header.compressed != VLI_UNKNOWN
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) && s->block_header.compressed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) != s->block.compressed)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) if (s->block_header.uncompressed != VLI_UNKNOWN
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) && s->block_header.uncompressed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) != s->block.uncompressed)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) s->block.hash.unpadded += s->block_header.size
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) + s->block.compressed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) #ifdef XZ_DEC_ANY_CHECK
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) s->block.hash.unpadded += check_sizes[s->check_type];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) if (s->check_type == XZ_CHECK_CRC32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) s->block.hash.unpadded += 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) s->block.hash.uncompressed += s->block.uncompressed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) s->block.hash.crc32 = xz_crc32(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) (const uint8_t *)&s->block.hash,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) sizeof(s->block.hash), s->block.hash.crc32);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) ++s->block.count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) /* Update the Index size and the CRC32 value. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) static void index_update(struct xz_dec *s, const struct xz_buf *b)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) size_t in_used = b->in_pos - s->in_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) s->index.size += in_used;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) s->crc32 = xz_crc32(b->in + s->in_start, in_used, s->crc32);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) * Decode the Number of Records, Unpadded Size, and Uncompressed Size
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) * fields from the Index field. That is, Index Padding and CRC32 are not
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) * decoded by this function.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) * This can return XZ_OK (more input needed), XZ_STREAM_END (everything
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) * successfully decoded), or XZ_DATA_ERROR (input is corrupt).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) static enum xz_ret dec_index(struct xz_dec *s, struct xz_buf *b)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) enum xz_ret ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) ret = dec_vli(s, b->in, &b->in_pos, b->in_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) if (ret != XZ_STREAM_END) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) index_update(s, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) switch (s->index.sequence) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) case SEQ_INDEX_COUNT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) s->index.count = s->vli;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) * Validate that the Number of Records field
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) * indicates the same number of Records as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) * there were Blocks in the Stream.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) if (s->index.count != s->block.count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) s->index.sequence = SEQ_INDEX_UNPADDED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) case SEQ_INDEX_UNPADDED:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) s->index.hash.unpadded += s->vli;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) s->index.sequence = SEQ_INDEX_UNCOMPRESSED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) case SEQ_INDEX_UNCOMPRESSED:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) s->index.hash.uncompressed += s->vli;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) s->index.hash.crc32 = xz_crc32(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) (const uint8_t *)&s->index.hash,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) sizeof(s->index.hash),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) s->index.hash.crc32);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) --s->index.count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) s->index.sequence = SEQ_INDEX_UNPADDED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) } while (s->index.count > 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) return XZ_STREAM_END;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) * Validate that the next four input bytes match the value of s->crc32.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) * s->pos must be zero when starting to validate the first byte.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) static enum xz_ret crc32_validate(struct xz_dec *s, struct xz_buf *b)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) if (b->in_pos == b->in_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) if (((s->crc32 >> s->pos) & 0xFF) != b->in[b->in_pos++])
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) s->pos += 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) } while (s->pos < 32);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) s->crc32 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) s->pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) return XZ_STREAM_END;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) #ifdef XZ_DEC_ANY_CHECK
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) * Skip over the Check field when the Check ID is not supported.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) * Returns true once the whole Check field has been skipped over.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) static bool check_skip(struct xz_dec *s, struct xz_buf *b)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) while (s->pos < check_sizes[s->check_type]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) if (b->in_pos == b->in_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) return false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) ++b->in_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) ++s->pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) s->pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) return true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) /* Decode the Stream Header field (the first 12 bytes of the .xz Stream). */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) static enum xz_ret dec_stream_header(struct xz_dec *s)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) if (!memeq(s->temp.buf, HEADER_MAGIC, HEADER_MAGIC_SIZE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) return XZ_FORMAT_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) if (xz_crc32(s->temp.buf + HEADER_MAGIC_SIZE, 2, 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) != get_le32(s->temp.buf + HEADER_MAGIC_SIZE + 2))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) if (s->temp.buf[HEADER_MAGIC_SIZE] != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) return XZ_OPTIONS_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) * Of integrity checks, we support only none (Check ID = 0) and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) * CRC32 (Check ID = 1). However, if XZ_DEC_ANY_CHECK is defined,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) * we will accept other check types too, but then the check won't
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) * be verified and a warning (XZ_UNSUPPORTED_CHECK) will be given.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) if (s->temp.buf[HEADER_MAGIC_SIZE + 1] > XZ_CHECK_MAX)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) return XZ_OPTIONS_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) s->check_type = s->temp.buf[HEADER_MAGIC_SIZE + 1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) #ifdef XZ_DEC_ANY_CHECK
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) if (s->check_type > XZ_CHECK_CRC32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) return XZ_UNSUPPORTED_CHECK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) if (s->check_type > XZ_CHECK_CRC32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) return XZ_OPTIONS_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) /* Decode the Stream Footer field (the last 12 bytes of the .xz Stream) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) static enum xz_ret dec_stream_footer(struct xz_dec *s)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) if (!memeq(s->temp.buf + 10, FOOTER_MAGIC, FOOTER_MAGIC_SIZE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) if (xz_crc32(s->temp.buf + 4, 6, 0) != get_le32(s->temp.buf))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) * Validate Backward Size. Note that we never added the size of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) * Index CRC32 field to s->index.size, thus we use s->index.size / 4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) * instead of s->index.size / 4 - 1.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) if ((s->index.size >> 2) != get_le32(s->temp.buf + 4))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) if (s->temp.buf[8] != 0 || s->temp.buf[9] != s->check_type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) * Use XZ_STREAM_END instead of XZ_OK to be more convenient
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) * for the caller.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) return XZ_STREAM_END;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) /* Decode the Block Header and initialize the filter chain. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) static enum xz_ret dec_block_header(struct xz_dec *s)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) enum xz_ret ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) * Validate the CRC32. We know that the temp buffer is at least
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) * eight bytes so this is safe.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) s->temp.size -= 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) if (xz_crc32(s->temp.buf, s->temp.size, 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) != get_le32(s->temp.buf + s->temp.size))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) s->temp.pos = 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) * Catch unsupported Block Flags. We support only one or two filters
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) * in the chain, so we catch that with the same test.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) #ifdef XZ_DEC_BCJ
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) if (s->temp.buf[1] & 0x3E)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) if (s->temp.buf[1] & 0x3F)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) return XZ_OPTIONS_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) /* Compressed Size */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) if (s->temp.buf[1] & 0x40) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) if (dec_vli(s, s->temp.buf, &s->temp.pos, s->temp.size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) != XZ_STREAM_END)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) s->block_header.compressed = s->vli;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) s->block_header.compressed = VLI_UNKNOWN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) /* Uncompressed Size */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) if (s->temp.buf[1] & 0x80) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) if (dec_vli(s, s->temp.buf, &s->temp.pos, s->temp.size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) != XZ_STREAM_END)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) s->block_header.uncompressed = s->vli;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) s->block_header.uncompressed = VLI_UNKNOWN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) #ifdef XZ_DEC_BCJ
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) /* If there are two filters, the first one must be a BCJ filter. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) s->bcj_active = s->temp.buf[1] & 0x01;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) if (s->bcj_active) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) if (s->temp.size - s->temp.pos < 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) return XZ_OPTIONS_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) ret = xz_dec_bcj_reset(s->bcj, s->temp.buf[s->temp.pos++]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) if (ret != XZ_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) * We don't support custom start offset,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) * so Size of Properties must be zero.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) if (s->temp.buf[s->temp.pos++] != 0x00)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) return XZ_OPTIONS_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) /* Valid Filter Flags always take at least two bytes. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) if (s->temp.size - s->temp.pos < 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) /* Filter ID = LZMA2 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) if (s->temp.buf[s->temp.pos++] != 0x21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) return XZ_OPTIONS_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) /* Size of Properties = 1-byte Filter Properties */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) if (s->temp.buf[s->temp.pos++] != 0x01)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) return XZ_OPTIONS_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) /* Filter Properties contains LZMA2 dictionary size. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) if (s->temp.size - s->temp.pos < 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) ret = xz_dec_lzma2_reset(s->lzma2, s->temp.buf[s->temp.pos++]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) if (ret != XZ_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) /* The rest must be Header Padding. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) while (s->temp.pos < s->temp.size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) if (s->temp.buf[s->temp.pos++] != 0x00)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) return XZ_OPTIONS_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) s->temp.pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) s->block.compressed = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) s->block.uncompressed = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) enum xz_ret ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) * Store the start position for the case when we are in the middle
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) * of the Index field.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) s->in_start = b->in_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) while (true) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) switch (s->sequence) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) case SEQ_STREAM_HEADER:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) * Stream Header is copied to s->temp, and then
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) * decoded from there. This way if the caller
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) * gives us only little input at a time, we can
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) * still keep the Stream Header decoding code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567) * simple. Similar approach is used in many places
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) * in this file.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) if (!fill_temp(s, b))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) * If dec_stream_header() returns
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) * XZ_UNSUPPORTED_CHECK, it is still possible
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) * to continue decoding if working in multi-call
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) * mode. Thus, update s->sequence before calling
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) * dec_stream_header().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) s->sequence = SEQ_BLOCK_START;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) ret = dec_stream_header(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) if (ret != XZ_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) /* fall through */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) case SEQ_BLOCK_START:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) /* We need one byte of input to continue. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) if (b->in_pos == b->in_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) /* See if this is the beginning of the Index field. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) if (b->in[b->in_pos] == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) s->in_start = b->in_pos++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) s->sequence = SEQ_INDEX;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) * Calculate the size of the Block Header and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) * prepare to decode it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) s->block_header.size
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) = ((uint32_t)b->in[b->in_pos] + 1) * 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) s->temp.size = s->block_header.size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608) s->temp.pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) s->sequence = SEQ_BLOCK_HEADER;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) /* fall through */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613) case SEQ_BLOCK_HEADER:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) if (!fill_temp(s, b))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) ret = dec_block_header(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) if (ret != XZ_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) s->sequence = SEQ_BLOCK_UNCOMPRESS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) /* fall through */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) case SEQ_BLOCK_UNCOMPRESS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626) ret = dec_block(s, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) if (ret != XZ_STREAM_END)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) s->sequence = SEQ_BLOCK_PADDING;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) /* fall through */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634) case SEQ_BLOCK_PADDING:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) * Size of Compressed Data + Block Padding
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) * must be a multiple of four. We don't need
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) * s->block.compressed for anything else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) * anymore, so we use it here to test the size
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640) * of the Block Padding field.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) while (s->block.compressed & 3) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) if (b->in_pos == b->in_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646) if (b->in[b->in_pos++] != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) ++s->block.compressed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652) s->sequence = SEQ_BLOCK_CHECK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) /* fall through */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) case SEQ_BLOCK_CHECK:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) if (s->check_type == XZ_CHECK_CRC32) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) ret = crc32_validate(s, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) if (ret != XZ_STREAM_END)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) #ifdef XZ_DEC_ANY_CHECK
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) else if (!check_skip(s, b)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668) s->sequence = SEQ_BLOCK_START;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) case SEQ_INDEX:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) ret = dec_index(s, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) if (ret != XZ_STREAM_END)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) s->sequence = SEQ_INDEX_PADDING;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678) /* fall through */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680) case SEQ_INDEX_PADDING:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) while ((s->index.size + (b->in_pos - s->in_start))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) & 3) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683) if (b->in_pos == b->in_size) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) index_update(s, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688) if (b->in[b->in_pos++] != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) /* Finish the CRC32 value and Index size. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693) index_update(s, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) /* Compare the hashes to validate the Index field. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696) if (!memeq(&s->block.hash, &s->index.hash,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) sizeof(s->block.hash)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) return XZ_DATA_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700) s->sequence = SEQ_INDEX_CRC32;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) /* fall through */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704) case SEQ_INDEX_CRC32:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) ret = crc32_validate(s, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706) if (ret != XZ_STREAM_END)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) s->temp.size = STREAM_HEADER_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) s->sequence = SEQ_STREAM_FOOTER;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) /* fall through */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714) case SEQ_STREAM_FOOTER:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) if (!fill_temp(s, b))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) return XZ_OK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) return dec_stream_footer(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) /* Never reached */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) * xz_dec_run() is a wrapper for dec_main() to handle some special cases in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) * multi-call and single-call decoding.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) * In multi-call mode, we must return XZ_BUF_ERROR when it seems clear that we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730) * are not going to make any progress anymore. This is to prevent the caller
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) * from calling us infinitely when the input file is truncated or otherwise
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) * corrupt. Since zlib-style API allows that the caller fills the input buffer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) * only when the decoder doesn't produce any new output, we have to be careful
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734) * to avoid returning XZ_BUF_ERROR too easily: XZ_BUF_ERROR is returned only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) * after the second consecutive call to xz_dec_run() that makes no progress.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737) * In single-call mode, if we couldn't decode everything and no error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) * occurred, either the input is truncated or the output buffer is too small.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) * Since we know that the last input byte never produces any output, we know
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) * that if all the input was consumed and decoding wasn't finished, the file
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741) * must be corrupt. Otherwise the output buffer has to be too small or the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) * file is corrupt in a way that decoding it produces too big output.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744) * If single-call decoding fails, we reset b->in_pos and b->out_pos back to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) * their original values. This is because with some filter chains there won't
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) * be any valid uncompressed data in the output buffer unless the decoding
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747) * actually succeeds (that's the price to pay of using the output buffer as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) * the workspace).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750) XZ_EXTERN enum xz_ret xz_dec_run(struct xz_dec *s, struct xz_buf *b)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) size_t in_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) size_t out_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754) enum xz_ret ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756) if (DEC_IS_SINGLE(s->mode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) xz_dec_reset(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759) in_start = b->in_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) out_start = b->out_pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) ret = dec_main(s, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763) if (DEC_IS_SINGLE(s->mode)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) if (ret == XZ_OK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765) ret = b->in_pos == b->in_size
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766) ? XZ_DATA_ERROR : XZ_BUF_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) if (ret != XZ_STREAM_END) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769) b->in_pos = in_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 770) b->out_pos = out_start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 771) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 772)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 773) } else if (ret == XZ_OK && in_start == b->in_pos
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 774) && out_start == b->out_pos) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 775) if (s->allow_buf_error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 776) ret = XZ_BUF_ERROR;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 777)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 778) s->allow_buf_error = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 779) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 780) s->allow_buf_error = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 781) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 782)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 783) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 784) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 785)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 786) XZ_EXTERN struct xz_dec *xz_dec_init(enum xz_mode mode, uint32_t dict_max)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 787) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 788) struct xz_dec *s = kmalloc(sizeof(*s), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 789) if (s == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 790) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 791)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 792) s->mode = mode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 793)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 794) #ifdef XZ_DEC_BCJ
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 795) s->bcj = xz_dec_bcj_create(DEC_IS_SINGLE(mode));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 796) if (s->bcj == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 797) goto error_bcj;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 798) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 799)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 800) s->lzma2 = xz_dec_lzma2_create(mode, dict_max);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 801) if (s->lzma2 == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 802) goto error_lzma2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 803)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 804) xz_dec_reset(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 805) return s;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 806)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 807) error_lzma2:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 808) #ifdef XZ_DEC_BCJ
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 809) xz_dec_bcj_end(s->bcj);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 810) error_bcj:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 811) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 812) kfree(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 813) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 814) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 815)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 816) XZ_EXTERN void xz_dec_reset(struct xz_dec *s)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 817) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 818) s->sequence = SEQ_STREAM_HEADER;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 819) s->allow_buf_error = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 820) s->pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 821) s->crc32 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 822) memzero(&s->block, sizeof(s->block));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 823) memzero(&s->index, sizeof(s->index));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 824) s->temp.pos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 825) s->temp.size = STREAM_HEADER_SIZE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 826) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 827)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 828) XZ_EXTERN void xz_dec_end(struct xz_dec *s)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 829) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 830) if (s != NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 831) xz_dec_lzma2_end(s->lzma2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 832) #ifdef XZ_DEC_BCJ
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 833) xz_dec_bcj_end(s->bcj);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 834) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 835) kfree(s);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 836) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 837) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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