diff options
Diffstat (limited to 'modules/xz-embedded/src/xz_dec_stream.c')
| -rw-r--r-- | modules/xz-embedded/src/xz_dec_stream.c | 102 |
1 files changed, 98 insertions, 4 deletions
diff --git a/modules/xz-embedded/src/xz_dec_stream.c b/modules/xz-embedded/src/xz_dec_stream.c index d6525506a1..2c41f5f1b0 100644 --- a/modules/xz-embedded/src/xz_dec_stream.c +++ b/modules/xz-embedded/src/xz_dec_stream.c @@ -35,7 +35,8 @@ struct xz_dec { SEQ_INDEX, SEQ_INDEX_PADDING, SEQ_INDEX_CRC32, - SEQ_STREAM_FOOTER + SEQ_STREAM_FOOTER, + SEQ_STREAM_PADDING } sequence; /* Position in variable-length integers and Check fields */ @@ -423,12 +424,12 @@ static enum xz_ret dec_stream_header(struct xz_dec *s) * 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 + 1] > XZ_CHECK_MAX) + return XZ_OPTIONS_ERROR; + 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; - if (s->check_type > XZ_CHECK_CRC32 && !IS_CRC64(s->check_type)) return XZ_UNSUPPORTED_CHECK; #else @@ -604,6 +605,8 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b) if (ret != XZ_OK) return ret; + /* Fall through */ + case SEQ_BLOCK_START: /* We need one byte of input to continue. */ if (b->in_pos == b->in_size) @@ -627,6 +630,8 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b) s->temp.pos = 0; s->sequence = SEQ_BLOCK_HEADER; + /* Fall through */ + case SEQ_BLOCK_HEADER: if (!fill_temp(s, b)) return XZ_OK; @@ -637,6 +642,8 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b) s->sequence = SEQ_BLOCK_UNCOMPRESS; + /* Fall through */ + case SEQ_BLOCK_UNCOMPRESS: ret = dec_block(s, b); if (ret != XZ_STREAM_END) @@ -644,6 +651,8 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b) s->sequence = SEQ_BLOCK_PADDING; + /* Fall through */ + case SEQ_BLOCK_PADDING: /* * Size of Compressed Data + Block Padding @@ -664,6 +673,8 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b) s->sequence = SEQ_BLOCK_CHECK; + /* Fall through */ + case SEQ_BLOCK_CHECK: if (s->check_type == XZ_CHECK_CRC32) { ret = crc_validate(s, b, 32); @@ -691,6 +702,8 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b) s->sequence = SEQ_INDEX_PADDING; + /* Fall through */ + case SEQ_INDEX_PADDING: while ((s->index.size + (b->in_pos - s->in_start)) & 3) { @@ -713,6 +726,8 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b) s->sequence = SEQ_INDEX_CRC32; + /* Fall through */ + case SEQ_INDEX_CRC32: ret = crc_validate(s, b, 32); if (ret != XZ_STREAM_END) @@ -721,11 +736,17 @@ static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b) s->temp.size = STREAM_HEADER_SIZE; s->sequence = SEQ_STREAM_FOOTER; + /* Fall through */ + case SEQ_STREAM_FOOTER: if (!fill_temp(s, b)) return XZ_OK; return dec_stream_footer(s); + + case SEQ_STREAM_PADDING: + /* Never reached, only silencing a warning */ + break; } } @@ -793,6 +814,79 @@ XZ_EXTERN enum xz_ret xz_dec_run(struct xz_dec *s, struct xz_buf *b) return ret; } +#ifdef XZ_DEC_CONCATENATED +XZ_EXTERN enum xz_ret xz_dec_catrun(struct xz_dec *s, struct xz_buf *b, + int finish) +{ + enum xz_ret ret; + + if (DEC_IS_SINGLE(s->mode)) { + xz_dec_reset(s); + finish = true; + } + + while (true) { + if (s->sequence == SEQ_STREAM_PADDING) { + /* + * Skip Stream Padding. Its size must be a multiple + * of four bytes which is tracked with s->pos. + */ + while (true) { + if (b->in_pos == b->in_size) { + /* + * Note that if we are repeatedly + * given no input and finish is false, + * we will keep returning XZ_OK even + * though no progress is being made. + * The lack of XZ_BUF_ERROR support + * isn't a problem here because a + * reasonable caller will eventually + * provide more input or set finish + * to true. + */ + if (!finish) + return XZ_OK; + + if (s->pos != 0) + return XZ_DATA_ERROR; + + return XZ_STREAM_END; + } + + if (b->in[b->in_pos] != 0x00) { + if (s->pos != 0) + return XZ_DATA_ERROR; + + break; + } + + ++b->in_pos; + s->pos = (s->pos + 1) & 3; + } + + /* + * More input remains. It should be a new Stream. + * + * In single-call mode xz_dec_run() will always call + * xz_dec_reset(). Thus, we need to do it here only + * in multi-call mode. + */ + if (DEC_IS_MULTI(s->mode)) + xz_dec_reset(s); + } + + ret = xz_dec_run(s, b); + + if (ret != XZ_STREAM_END) + break; + + s->sequence = SEQ_STREAM_PADDING; + } + + return ret; +} +#endif + XZ_EXTERN struct xz_dec *xz_dec_init(enum xz_mode mode, uint32_t dict_max) { struct xz_dec *s = kmalloc(sizeof(*s), GFP_KERNEL); |