cpp-httplib/test/fuzzing/server_fuzzer.cc

#include <memory>
#include <httplib.h>

class FuzzedStream : public httplib::Stream {
 public:
  FuzzedStream(const uint8_t* data, size_t size)
      : data_(data), size_(size), read_pos_(0) {}

  ssize_t read(char* ptr, size_t size) override {
    if (size + read_pos_ > size_) {
      size = size_ - read_pos_;
    }
    memcpy(ptr, data_ + read_pos_, size);
    read_pos_ += size;
    return size;
  }

  ssize_t write(const char* ptr, size_t size) override {
    response_.append(ptr, size);
    return static_cast<int>(size);
  }

  int write(const char* ptr) { return write(ptr, strlen(ptr)); }

  int write(const std::string& s) { return write(s.data(), s.size()); }

  std::string get_remote_addr() const { return ""; }

  bool is_readable() const override { return true; }

  bool is_writable() const override { return true; }

  void get_remote_ip_and_port(std::string &ip, int &port) const override {
    ip = "127.0.0.1";
    port = 8080;
  }

 private:
  const uint8_t* data_;
  size_t size_;
  size_t read_pos_;
  std::string response_;
};

class FuzzableServer : public httplib::Server {
 public:
  void ProcessFuzzedRequest(FuzzedStream& stream) {
    bool connection_close = false;
    process_request(stream, /*last_connection=*/false, connection_close,
                    nullptr);
  }
};

static FuzzableServer g_server;

extern "C" int LLVMFuzzerInitialize(int* argc, char*** argv) {
  g_server.Get(R"(.*)",
                [&](const httplib::Request& req, httplib::Response& res) {
                  res.set_content("response content", "text/plain");
                });
  g_server.Post(R"(.*)",
                 [&](const httplib::Request& req, httplib::Response& res) {
                   res.set_content("response content", "text/plain");
                 });
  g_server.Put(R"(.*)",
                [&](const httplib::Request& req, httplib::Response& res) {
                  res.set_content("response content", "text/plain");
                });
  g_server.Patch(R"(.*)",
                  [&](const httplib::Request& req, httplib::Response& res) {
                    res.set_content("response content", "text/plain");
                  });
  g_server.Delete(R"(.*)",
                   [&](const httplib::Request& req, httplib::Response& res) {
                     res.set_content("response content", "text/plain");
                   });
  g_server.Options(R"(.*)",
                    [&](const httplib::Request& req, httplib::Response& res) {
                      res.set_content("response content", "text/plain");
                    });
  return 0;
}

extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
  FuzzedStream stream{data, size};
  g_server.ProcessFuzzedRequest(stream);
  return 0;
}