Add ClusterFuzzLite integration

.clusterfuzzlite/Dockerfile

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+FROM gcr.io/oss-fuzz-base/base-builder
+RUN apt-get update && apt-get install -y make autoconf automake libtool
+COPY . $SRC/lorawan-parser
+COPY .clusterfuzzlite/build.sh $SRC/build.sh
+COPY .clusterfuzzlite/*.c $SRC/
+WORKDIR lorawan-parser

.clusterfuzzlite/build.sh

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+#!/bin/bash
+autoreconf -fi
+./configure
+make
+
+$CC $CFLAGS $LIB_FUZZING_ENGINE $SRC/fuzzer.c -Wl,--whole-archive $SRC/lorawan-parser/lw/.libs/liblorawan.a -Wl,--whole-archive $SRC/lorawan-parser/lib/libloragw$SRC/.libs/libloragw.a -Wl,--whole-archive $SRC/lorawan-parser/lib/.libs/lib.a -Wl,--allow-multiple-definition -I$SRC/lorawan-parser/util/parser -I$SRC/lorawan-parser/lib/libloragw/inc -I$SRC/lorawan-parser/lib -I$SRC/lorawan-parser/lw  -o $OUT/fuzzer

.clusterfuzzlite/fuzzer.c

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+#include <string.h>
+#include <stdint.h>
+#include <stddef.h>
+#include "json.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+    if (size == 0)
+        return 0;
+
+    // Ensure `data` is null-terminated
+    char input[size + 1];
+    memcpy(input, data, size);
+    input[size] = '\0';
+
+    // Call the target function with the input
+    JsonNode *result = json_decode((const char *)input);
+
+    // Free the result to avoid memory leaks
+    json_delete(result);
+
+    return 0;
+}
+

.clusterfuzzlite/project.yaml

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+language: c

.github/workflows/cflite_pr.yml

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+name: ClusterFuzzLite PR fuzzing
+on:
+  workflow_dispatch:
+  pull_request:
+    branches: [ master ]
+permissions: read-all
+jobs:
+  PR:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        sanitizer: [address]
+    steps:
+    - name: Build Fuzzers (${{ matrix.sanitizer }})
+      id: build
+      uses: google/clusterfuzzlite/actions/build_fuzzers@v1
+      with:
+        sanitizer: ${{ matrix.sanitizer }}
+        language: c++
+        bad-build-check: false
+    - name: Run Fuzzers (${{ matrix.sanitizer }})
+      id: run
+      uses: google/clusterfuzzlite/actions/run_fuzzers@v1
+      with:
+        github-token: ${{ secrets.GITHUB_TOKEN }}
+        fuzz-seconds: 100
+        mode: 'code-change'
+        report-unreproducible-crashes: false
+        sanitizer: ${{ matrix.sanitizer }}