50 строки
1.2 KiB
C
50 строки
1.2 KiB
C
|
#include <linux/zutil.h>
|
||
|
|
#include <linux/errno.h>
|
||
|
|
#include <linux/slab.h>
|
||
|
|
#include <linux/vmalloc.h>
|
||
|
|
|
||
|
|
/* Utility function: initialize zlib, unpack binary blob, clean up zlib,
|
||
|
|
* return len or negative error code.
|
||
|
|
*/
|
||
|
|
int zlib_inflate_blob(void *gunzip_buf, unsigned int sz,
|
||
|
|
const void *buf, unsigned int len)
|
||
|
|
{
|
||
|
|
const u8 *zbuf = buf;
|
||
|
|
struct z_stream_s *strm;
|
||
|
|
int rc;
|
||
|
|
|
||
|
|
rc = -ENOMEM;
|
||
|
|
strm = kmalloc(sizeof(*strm), GFP_KERNEL);
|
||
|
|
if (strm == NULL)
|
||
|
|
goto gunzip_nomem1;
|
||
|
|
strm->workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
|
||
|
|
if (strm->workspace == NULL)
|
||
|
|
goto gunzip_nomem2;
|
||
|
|
|
||
|
|
/* gzip header (1f,8b,08... 10 bytes total + possible asciz filename)
|
||
|
|
* expected to be stripped from input
|
||
|
|
*/
|
||
|
|
strm->next_in = zbuf;
|
||
|
|
strm->avail_in = len;
|
||
|
|
strm->next_out = gunzip_buf;
|
||
|
|
strm->avail_out = sz;
|
||
|
|
|
||
|
|
rc = zlib_inflateInit2(strm, -MAX_WBITS);
|
||
|
|
if (rc == Z_OK) {
|
||
|
|
rc = zlib_inflate(strm, Z_FINISH);
|
||
|
|
/* after Z_FINISH, only Z_STREAM_END is "we unpacked it all" */
|
||
|
|
if (rc == Z_STREAM_END)
|
||
|
|
rc = sz - strm->avail_out;
|
||
|
|
else
|
||
|
|
rc = -EINVAL;
|
||
|
|
zlib_inflateEnd(strm);
|
||
|
|
} else
|
||
|
|
rc = -EINVAL;
|
||
|
|
|
||
|
|
kfree(strm->workspace);
|
||
|
|
gunzip_nomem2:
|
||
|
|
kfree(strm);
|
||
|
|
gunzip_nomem1:
|
||
|
|
return rc; /* returns Z_OK (0) if successful */
|
||
|
|
}
|