diff options
Diffstat (limited to 'lib/zlib_inflate/infutil.c')
-rw-r--r-- | lib/zlib_inflate/infutil.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/lib/zlib_inflate/infutil.c b/lib/zlib_inflate/infutil.c new file mode 100644 index 00000000..4824c2cc --- /dev/null +++ b/lib/zlib_inflate/infutil.c @@ -0,0 +1,49 @@ +#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 */ +} |