1 // Copyright 2019 Google LLC 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 // Provides a class to marshall protobufs in and out of the sandbox 16 17 #ifndef SANDBOXED_API_VAR_PROTO_H_ 18 #define SANDBOXED_API_VAR_PROTO_H_ 19 20 #include <cinttypes> 21 #include <cstdint> 22 #include <ctime> 23 #include <memory> 24 #include <string> 25 #include <type_traits> 26 #include <utility> 27 #include <vector> 28 29 #include "absl/base/attributes.h" 30 #include "absl/base/macros.h" 31 #include "absl/log/log.h" 32 #include "absl/status/status.h" 33 #include "absl/status/statusor.h" 34 #include "absl/utility/utility.h" 35 #include "sandboxed_api/proto_helper.h" 36 #include "sandboxed_api/util/status_macros.h" 37 #include "sandboxed_api/var_lenval.h" 38 #include "sandboxed_api/var_ptr.h" 39 40 namespace sapi::v { 41 42 template <typename T> 43 class Proto : public Var { 44 public: 45 static_assert(std::is_base_of<google::protobuf::MessageLite, T>::value, 46 "Template argument must be a proto message"); 47 48 ABSL_DEPRECATED("Use Proto<>::FromMessage() instead") Proto(const T & proto)49 explicit Proto(const T& proto) 50 : wrapped_var_(SerializeProto(proto).value()) {} 51 FromMessage(const T & proto)52 static absl::StatusOr<Proto<T>> FromMessage(const T& proto) { 53 SAPI_ASSIGN_OR_RETURN(std::vector<uint8_t> len_val, SerializeProto(proto)); 54 return absl::StatusOr<Proto<T>>(absl::in_place, proto); 55 } 56 GetSize()57 size_t GetSize() const final { return wrapped_var_.GetSize(); } GetType()58 Type GetType() const final { return Type::kProto; } GetTypeString()59 std::string GetTypeString() const final { return "Protobuf"; } ToString()60 std::string ToString() const final { return "Protobuf"; } 61 GetRemote()62 void* GetRemote() const override { return wrapped_var_.GetRemote(); } GetLocal()63 void* GetLocal() const override { return wrapped_var_.GetLocal(); } 64 65 // Returns a copy of the stored protobuf object. GetMessage()66 absl::StatusOr<T> GetMessage() const { 67 return DeserializeProto<T>( 68 reinterpret_cast<const char*>(wrapped_var_.GetData()), 69 wrapped_var_.GetDataSize()); 70 } 71 72 ABSL_DEPRECATED("Use GetMessage() instead") GetProtoCopy()73 std::unique_ptr<T> GetProtoCopy() const { 74 if (auto proto = GetMessage(); proto.ok()) { 75 return std::make_unique<T>(*std::move(proto)); 76 } 77 return nullptr; 78 } 79 SetRemote(void *)80 void SetRemote(void* /* remote */) override { 81 // We do not support that much indirection (pointer to a pointer to a 82 // protobuf) as it is unlikely that this is wanted behavior. If you expect 83 // this to work, please get in touch with us. 84 LOG(FATAL) << "SetRemote not supported on protobufs."; 85 } 86 87 protected: 88 // Forward a couple of function calls to the actual var. Allocate(RPCChannel * rpc_channel,bool automatic_free)89 absl::Status Allocate(RPCChannel* rpc_channel, bool automatic_free) override { 90 return wrapped_var_.Allocate(rpc_channel, automatic_free); 91 } 92 Free(RPCChannel * rpc_channel)93 absl::Status Free(RPCChannel* rpc_channel) override { 94 return absl::OkStatus(); 95 } 96 TransferToSandboxee(RPCChannel * rpc_channel,pid_t pid)97 absl::Status TransferToSandboxee(RPCChannel* rpc_channel, 98 pid_t pid) override { 99 return wrapped_var_.TransferToSandboxee(rpc_channel, pid); 100 } 101 TransferFromSandboxee(RPCChannel * rpc_channel,pid_t pid)102 absl::Status TransferFromSandboxee(RPCChannel* rpc_channel, 103 pid_t pid) override { 104 return wrapped_var_.TransferFromSandboxee(rpc_channel, pid); 105 } 106 107 private: 108 friend class absl::StatusOr<Proto<T>>; 109 Proto(std::vector<uint8_t> data)110 explicit Proto(std::vector<uint8_t> data) : wrapped_var_(std::move(data)) {} 111 112 // The management of reading/writing the data to the sandboxee is handled by 113 // the LenVal class. 114 LenVal wrapped_var_; 115 }; 116 117 } // namespace sapi::v 118 119 #endif // SANDBOXED_API_VAR_PROTO_H_ 120