Skip to content

Commit

Permalink
std.compress.zstandard: add window size limit param
Browse files Browse the repository at this point in the history
  • Loading branch information
dweiller committed Jan 26, 2023
1 parent 1436b6b commit 0e61592
Showing 1 changed file with 10 additions and 2 deletions.
12 changes: 10 additions & 2 deletions lib/std/compress/zstandard/decompress.zig
Original file line number Diff line number Diff line change
Expand Up @@ -562,7 +562,12 @@ pub fn decodeZStandardFrame(dest: []u8, src: []const u8, verify_checksum: bool)
/// `decodeZStandardFrame()`. Returns `error.WindowSizeUnknown` if the frame
/// does not declare its content size or a window descriptor (this indicates a
/// malformed frame).
pub fn decodeZStandardFrameAlloc(allocator: std.mem.Allocator, src: []const u8, verify_checksum: bool) ![]u8 {
pub fn decodeZStandardFrameAlloc(
allocator: std.mem.Allocator,
src: []const u8,
verify_checksum: bool,
window_size_max: usize,
) ![]u8 {
var result = std.ArrayList(u8).init(allocator);
assert(readInt(u32, src[0..4]) == frame.ZStandard.magic_number);
var consumed_count: usize = 4;
Expand All @@ -572,7 +577,10 @@ pub fn decodeZStandardFrameAlloc(allocator: std.mem.Allocator, src: []const u8,
if (frame_header.descriptor.dictionary_id_flag != 0) return error.DictionaryIdFlagUnsupported;

const window_size_raw = frameWindowSize(frame_header) orelse return error.WindowSizeUnknown;
const window_size = std.math.cast(usize, window_size_raw) orelse return error.WindowTooLarge;
const window_size = if (window_size_raw > window_size_max)
return error.WindowTooLarge
else
@intCast(usize, window_size_raw);

const should_compute_checksum = frame_header.descriptor.content_checksum_flag and verify_checksum;
var hash = if (should_compute_checksum) std.hash.XxHash64.init(0) else null;
Expand Down

0 comments on commit 0e61592

Please sign in to comment.