fuzzers: add DTLS fuzzer

to fuzz the code parsing DTLS packets for DTLS-STUN piggybacking

BUG=webrtc:367395350

Change-Id: Ifa1a52ef56b322e465604e8d49ae18e5dc27613f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/371360
Reviewed-by: Jonas Oreland <jonaso@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Commit-Queue: Philipp Hancke <phancke@meta.com>
Cr-Commit-Position: refs/heads/main@{#43562}

test/fuzzers/BUILD.gn

@@ -102,6 +102,17 @@ webrtc_fuzzer_test("vp9_depacketizer_fuzzer") {
   ]
 }
 
+webrtc_fuzzer_test("dtls_utils_fuzzer") {
+  sources = [ "dtls_utils_fuzzer.cc" ]
+  deps = [
+    "../../api:array_view",
+    "../../p2p:dtls_utils",
+  ]
+
+  # Seed from boringssl DTLS corpus.
+  seed_corpus = "../../third_party/boringssl/src/fuzz/dtls_client_corpus"
+}
+
 webrtc_fuzzer_test("vp8_qp_parser_fuzzer") {
   sources = [ "vp8_qp_parser_fuzzer.cc" ]
   deps = [

test/fuzzers/DEPS

@@ -2,4 +2,5 @@ include_rules = [
   "+audio",
   "+pc",
   "+net/dcsctp",
+  "+p2p",
 ]

test/fuzzers/dtls_utils_fuzzer.cc

@@ -0,0 +1,21 @@
+/*
+ *  Copyright (c) 2024 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+#include <cstddef>
+#include <cstdint>
+
+#include "api/array_view.h"
+#include "p2p/dtls/dtls_utils.h"
+
+namespace webrtc {
+void FuzzOneInput(const uint8_t* data, size_t size) {
+  cricket::GetDtlsHandshakeAcks(rtc::MakeArrayView(data, size));
+}
+
+}  // namespace webrtc