sandboxed-api/oss-internship-2020/jsonnet/examples/jsonnet_base_transaction.h

// Copyright 2020 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include <syscall.h>
#include <libgen.h>

#include "sandboxed_api/transaction.h"
#include "sandboxed_api/vars.h"
#include "sandboxed_api/util/flag.h"

#include "jsonnet_sapi.sapi.h"

class JsonnetSapiTransactionSandbox : public JsonnetSandbox {
 public:
  explicit JsonnetSapiTransactionSandbox(std::string in_file, std::string out_file)
      : in_file_(in_file), out_file_(out_file) {}

  std::unique_ptr<sandbox2::Policy> ModifyPolicy(
      sandbox2::PolicyBuilder *) override {
    return sandbox2::PolicyBuilder()
        .AllowStaticStartup()
        .AllowOpen()
        .AllowRead()
        .AllowWrite()
        .AllowStat()
        .AllowSystemMalloc()
        .AllowExit()
        .AllowSyscalls({
            __NR_futex,
            __NR_close,
        })
        .AddDirectoryAt(dirname(&out_file_[0]), "/output", /*is_ro=*/false)
        .AddDirectoryAt(dirname(&in_file_[0]), "/input", true)
        .BuildOrDie();
  }

 private:
  std::string in_file_;
  std::string out_file_;
};

class JsonnetTransaction : public sapi::Transaction {
 public:
  JsonnetTransaction(std::string in_file, std::string out_file)
    : sapi::Transaction(std::make_unique<JsonnetSapiTransactionSandbox>(in_file, out_file)),
    in_file_(in_file), out_file_(out_file)
  {
    sapi::Transaction::set_retry_count(0); // Try once, no retries
    sapi::Transaction::SetTimeLimit(0);  // Infinite time limit
  }

 private:
  absl::Status Main() override;
  std::string in_file_;
  std::string out_file_;

};