Commit 4aa6a3f8344a450433a21862890e791c76bb464b | lib/zig/yaml

author	Meghan Denny <hello@nektro.net> 2025-08-25 02:05:22 -07:00
committer	Meghan Denny <hello@nektro.net> 2025-08-25 02:05:22 -07:00
log	4aa6a3f8344a450433a21862890e791c76bb464b
tree	294c1b758e84c27e61d3e7c602cf6cdfba154291
parent	b0fb5f64914ea219b35b778c371fa4d8237b8526

add fuzzing

6 files changed, 181 insertions(+), 0 deletions(-)

.gitignore+2

...	...	@@ -2,3 +2,5 @@
2	2	.zigmod
3	3	zigmod.lock
4	4	deps.zig
	5	zig-out
	6	fuzz/output

build.zig+43

...	...	@@ -23,4 +23,47 @@ pub fn build(b: *std.Build) void {
23	23	const tests_run = b.addRunArtifact(tests);
24	24	tests_run.has_side_effects = true;
25	25	test_step.dependOn(&tests_run.step);
	26
	27	//
	28
	29	const fuzz_exe = addFuzzer(b, target, "yaml", &.{});
	30
	31	const fuzz_run = b.addSystemCommand(&.{"afl-fuzz"});
	32	fuzz_run.step.dependOn(&fuzz_exe.step);
	33	fuzz_run.addArgs(&.{ "-i", "fuzz/input" });
	34	fuzz_run.addArgs(&.{ "-o", "fuzz/output" });
	35	fuzz_run.addArgs(&.{ "-x", "fuzz/yaml.dict" });
	36	fuzz_run.addArg("--");
	37	fuzz_run.addFileArg(fuzz_exe.source);
	38
	39	const fuzz_step = b.step("fuzz", "Run AFL++");
	40	fuzz_step.dependOn(&fuzz_run.step);
	41	}
	42
	43	fn addFuzzer(b: std.Build, target: std.Build.ResolvedTarget, comptime name: []const u8, afl_clang_args: []const []const u8) std.Build.Step.InstallFile {
	44	const fuzz_lib = b.addStaticLibrary(.{
	45	.name = "fuzz-" ++ name ++ "-lib",
	46	.root_source_file = b.path("fuzz/main.zig"),
	47	.target = target,
	48	.optimize = .Debug,
	49	});
	50	fuzz_lib.want_lto = true;
	51	fuzz_lib.bundle_compiler_rt = true;
	52	fuzz_lib.use_llvm = true;
	53	fuzz_lib.use_lld = true;
	54	fuzz_lib.root_module.pic = true;
	55
	56	deps.addAllTo(fuzz_lib);
	57
	58	const fuzz_executable_name = "fuzz-" ++ name;
	59
	60	const fuzz_compile = b.addSystemCommand(&.{ "afl-clang-lto", "-v", "-o" });
	61	const output_path = fuzz_compile.addOutputFileArg(fuzz_executable_name);
	62	fuzz_compile.addArtifactArg(fuzz_lib);
	63	fuzz_compile.addArgs(afl_clang_args);
	64
	65	const fuzz_install = b.addInstallBinFile(output_path, fuzz_executable_name);
	66	fuzz_install.step.dependOn(&fuzz_compile.step);
	67
	68	return fuzz_install;
26	69	}

fuzz/input/input.yml created+31

...	...	@@ -0,0 +1,31 @@
	1	id: g982zq6e8wsvnmduerpbf8787hu85brugmngn8wf
	2	name: yaml
	3	main: yaml.zig
	4	license: MIT
	5	description: A Yaml parser built on top of libyaml
	6	dependencies:
	7	- src: git https://github.com/yaml/libyaml tag-0.2.5
	8	id: 8mdbh0zuneb0i3hs5jby5je0heem1i6yxusl7c8y8qx68hqc
	9	license: MIT
	10	c_include_dirs:
	11	- include
	12	c_source_flags:
	13	- -DYAML_VERSION_MAJOR=0
	14	- -DYAML_VERSION_MINOR=2
	15	- -DYAML_VERSION_PATCH=5
	16	- -DYAML_VERSION_STRING="0.2.5"
	17	- -DYAML_DECLARE_STATIC=1
	18	c_source_files:
	19	- src/api.c
	20	- src/dumper.c
	21	- src/emitter.c
	22	- src/loader.c
	23	- src/parser.c
	24	- src/reader.c
	25	- src/scanner.c
	26	- src/writer.c
	27
	28	- src: git https://github.com/nektro/zig-extras
	29
	30	root_dependencies:
	31	- src: git https://github.com/nektro/zig-expect

fuzz/main.zig created+16

...	...	@@ -0,0 +1,16 @@
	1	const std = @import("std");
	2	const yaml = @import("yaml");
	3	const nfs = @import("nfs");
	4
	5	pub export fn main() void {
	6	var gpa = std.heap.GeneralPurposeAllocator(.{}){};
	7	defer std.debug.assert(gpa.deinit() == .ok);
	8	const allocator = gpa.allocator();
	9
	10	const stdin = nfs.stdin();
	11	const input = stdin.readToEndAlloc(allocator, 1024 * 1024, null) catch @panic("too big");
	12	defer allocator.free(input);
	13
	14	const doc = yaml.parse(allocator, input) catch return;
	15	defer doc.deinit(allocator);
	16	}

fuzz/yaml.dict created+80

...	...	@@ -0,0 +1,80 @@
	1	# https://github.com/AFLplusplus/AFLplusplus/blob/stable/dictionaries/yaml.dict
	2	# sources:
	3	# - https://en.wikipedia.org/wiki/YAML
	4	# - https://yaml.org/spec/1.1/
	5	# - https://yaml.org/type/
	6
	7	directive_yaml="%YAML 1.2"
	8	directive_tag="%TAG !yaml! tag:yaml.org,2002:"
	9	directive_tag2="%TAG !m! !my-"
	10	true="true"
	11	caps_true="TRUE"
	12	caps_false="FALSE"
	13	literal_true="YES"
	14	literal_false="NO"
	15	false="false"
	16	start="---"
	17	comment="#"
	18	list="- "
	19	key="k: "
	20	walrus="=:"
	21	question_key="?k: "
	22	number="\"0e5\""
	23	expand="!!"
	24	list="[a,b]"
	25	dict="{k: v, x: y}"
	26	value=": v"
	27	exponent="e+03"
	28	neg_inf="-.inf"
	29	nan=".NaN"
	30	end="..."
	31	quoted_key="'k'"
	32	newline="k: \|"
	33	newline2="k: >"
	34	anchor="&a"
	35	reference="*a"
	36	type_binary="!!binary"
	37	type_bool="!!bool"
	38	type_float="!!float"
	39	type_int="!!int"
	40	type_map="!!map"
	41	type_merge="!!merge"
	42	type_null="!!null"
	43	type_omap="!!omap"
	44	type_pairs="!!pairs"
	45	type_seq="!!seq"
	46	type_set="!!set"
	47	type_str="!!str"
	48	type_timestamp="!!timestamp"
	49	type_value="!!value"
	50	type_yaml="!!yaml"
	51	type_python="!!python"
	52	merge = "<<"
	53	number_separation="_"
	54	decimal_number="+30_123"
	55	octal_number="0123"
	56	hex_number="0x_12_23"
	57	bin_number="0b1001_1001"
	58	sexa_number="123:34:75"
	59	complex_mapping="? "
	60	litteral_style=" \|"
	61	folded_style=" >"
	62	timestamp="2001-12-14t21:59:43.10-05:00"
	63	escaped_unicode="\\u2029"
	64	"["
	65	"]"
	66	"{"
	67	"}"
	68	"-"
	69	","
	70	"&"
	71	"<<"
	72	":"
	73	"\|"
	74	"!!"
	75	">"
	76	"\""
	77	"'"
	78	integer="123"
	79	float="12.5"
	80	mantissa="1.3e+9"

shell.nix created+9

...	...	@@ -0,0 +1,9 @@
	1	with import <nixpkgs> {};
	2
	3	pkgs.mkShell {
	4	nativeBuildInputs = with pkgs; [
	5	aflplusplus
	6	];
	7
	8	hardeningDisable = [ "all" ];
	9	}