diff options
Diffstat (limited to 'archival/libunarchive/decompress_unzip.c')
| -rw-r--r-- | archival/libunarchive/decompress_unzip.c | 53 |
1 files changed, 40 insertions, 13 deletions
diff --git a/archival/libunarchive/decompress_unzip.c b/archival/libunarchive/decompress_unzip.c index 1b2d587..8da9b5c 100644 --- a/archival/libunarchive/decompress_unzip.c +++ b/archival/libunarchive/decompress_unzip.c @@ -83,29 +83,31 @@ typedef struct huft_s { } huft_t; static int gunzip_src_fd; -unsigned int gunzip_bytes_out; /* number of output bytes */ +static unsigned int gunzip_bytes_out; /* number of output bytes */ static unsigned int gunzip_outbuf_count; /* bytes in output buffer */ -/* This is used to sanify any unused bits from the bitbuffer - * so they arent skipped when reading trailers (trailing headers) */ -//unsigned char gunzip_in_buffer_count; -//unsigned char *gunzip_in_buffer; - /* gunzip_window size--must be a power of two, and * at least 32K for zip's deflate method */ static const int gunzip_wsize = 0x8000; - static unsigned char *gunzip_window; + static unsigned int *gunzip_crc_table; -unsigned int gunzip_crc; +static unsigned int gunzip_crc; /* If BMAX needs to be larger than 16, then h and x[] should be ulg. */ #define BMAX 16 /* maximum bit length of any code (16 for explode) */ #define N_MAX 288 /* maximum number of codes in any set */ +/* bitbuffer */ static unsigned int gunzip_bb; /* bit buffer */ static unsigned char gunzip_bk; /* bits in bit buffer */ +/* These control the size of the bytebuffer */ +#define BYTEBUFFER_MAX 0x8000 +static unsigned char *bytebuffer = NULL; +static unsigned int bytebuffer_offset = 0; +static unsigned int bytebuffer_size = 0; + static const unsigned short mask_bits[] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff @@ -142,11 +144,6 @@ static const unsigned char border[] = { 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 }; -#define BYTEBUFFER_MAX 0x8000 -unsigned char *bytebuffer = NULL; -unsigned int bytebuffer_offset = 0; -unsigned int bytebuffer_size = 0; - static void fill_bytebuffer(void) { if (bytebuffer_offset >= bytebuffer_size) { @@ -1011,3 +1008,33 @@ extern int inflate(int in, int out) GZ_gzReadClose(); return 0; } + +extern void check_trailer_gzip(int src_fd) +{ + unsigned int stored_crc = 0; + unsigned char count; + + /* top up the input buffer with the rest of the trailer */ + count = bytebuffer_size - bytebuffer_offset; + if (count < 8) { + xread_all(src_fd, &bytebuffer[bytebuffer_size], 8 - count); + bytebuffer_size += 8 - count; + } + for (count = 0; count != 4; count++) { + stored_crc |= (bytebuffer[bytebuffer_offset] << (count * 8)); + bytebuffer_offset++; + } + + /* Validate decompression - crc */ + if (stored_crc != (gunzip_crc ^ 0xffffffffL)) { + error_msg_and_die("crc error"); + } + + /* Validate decompression - size */ + if (gunzip_bytes_out != + (bytebuffer[bytebuffer_offset] | (bytebuffer[bytebuffer_offset+1] << 8) | + (bytebuffer[bytebuffer_offset+2] << 16) | (bytebuffer[bytebuffer_offset+3] << 24))) { + error_msg_and_die("Incorrect length, but crc is correct"); + } + +} |