1 // Copyright 2016 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef V8_VALUE_SERIALIZER_H_ 6 #define V8_VALUE_SERIALIZER_H_ 7 8 #include <cstdint> 9 #include <vector> 10 11 #include "include/v8.h" 12 #include "src/base/compiler-specific.h" 13 #include "src/base/macros.h" 14 #include "src/identity-map.h" 15 #include "src/maybe-handles.h" 16 #include "src/messages.h" 17 #include "src/vector.h" 18 #include "src/zone/zone.h" 19 20 namespace v8 { 21 namespace internal { 22 23 class BigInt; 24 class HeapNumber; 25 class Isolate; 26 class JSArrayBuffer; 27 class JSArrayBufferView; 28 class JSDate; 29 class JSMap; 30 class JSRegExp; 31 class JSSet; 32 class JSValue; 33 class MutableHeapNumber; 34 class Object; 35 class Oddball; 36 class Smi; 37 class WasmMemoryObject; 38 class WasmModuleObject; 39 40 enum class SerializationTag : uint8_t; 41 42 /** 43 * Writes V8 objects in a binary format that allows the objects to be cloned 44 * according to the HTML structured clone algorithm. 45 * 46 * Format is based on Blink's previous serialization logic. 47 */ 48 class ValueSerializer { 49 public: 50 ValueSerializer(Isolate* isolate, v8::ValueSerializer::Delegate* delegate); 51 ~ValueSerializer(); 52 53 /* 54 * Writes out a header, which includes the format version. 55 */ 56 void WriteHeader(); 57 58 /* 59 * Serializes a V8 object into the buffer. 60 */ 61 Maybe<bool> WriteObject(Handle<Object> object) V8_WARN_UNUSED_RESULT; 62 63 /* 64 * Returns the stored data. This serializer should not be used once the buffer 65 * is released. The contents are undefined if a previous write has failed. 66 */ 67 std::vector<uint8_t> ReleaseBuffer(); 68 69 /* 70 * Returns the buffer, allocated via the delegate, and its size. 71 * Caller assumes ownership of the buffer. 72 */ 73 std::pair<uint8_t*, size_t> Release(); 74 75 /* 76 * Marks an ArrayBuffer as havings its contents transferred out of band. 77 * Pass the corresponding JSArrayBuffer in the deserializing context to 78 * ValueDeserializer::TransferArrayBuffer. 79 */ 80 void TransferArrayBuffer(uint32_t transfer_id, 81 Handle<JSArrayBuffer> array_buffer); 82 83 /* 84 * Publicly exposed wire format writing methods. 85 * These are intended for use within the delegate's WriteHostObject method. 86 */ 87 void WriteUint32(uint32_t value); 88 void WriteUint64(uint64_t value); 89 void WriteRawBytes(const void* source, size_t length); 90 void WriteDouble(double value); 91 92 /* 93 * Indicate whether to treat ArrayBufferView objects as host objects, 94 * i.e. pass them to Delegate::WriteHostObject. This should not be 95 * called when no Delegate was passed. 96 * 97 * The default is not to treat ArrayBufferViews as host objects. 98 */ 99 void SetTreatArrayBufferViewsAsHostObjects(bool mode); 100 101 private: 102 // Managing allocations of the internal buffer. 103 Maybe<bool> ExpandBuffer(size_t required_capacity); 104 105 // Writing the wire format. 106 void WriteTag(SerializationTag tag); 107 template <typename T> 108 void WriteVarint(T value); 109 template <typename T> 110 void WriteZigZag(T value); 111 void WriteOneByteString(Vector<const uint8_t> chars); 112 void WriteTwoByteString(Vector<const uc16> chars); 113 void WriteBigIntContents(BigInt* bigint); 114 Maybe<uint8_t*> ReserveRawBytes(size_t bytes); 115 116 // Writing V8 objects of various kinds. 117 void WriteOddball(Oddball* oddball); 118 void WriteSmi(Smi* smi); 119 void WriteHeapNumber(HeapNumber* number); 120 void WriteMutableHeapNumber(MutableHeapNumber* number); 121 void WriteBigInt(BigInt* bigint); 122 void WriteString(Handle<String> string); 123 Maybe<bool> WriteJSReceiver(Handle<JSReceiver> receiver) 124 V8_WARN_UNUSED_RESULT; 125 Maybe<bool> WriteJSObject(Handle<JSObject> object) V8_WARN_UNUSED_RESULT; 126 Maybe<bool> WriteJSObjectSlow(Handle<JSObject> object) V8_WARN_UNUSED_RESULT; 127 Maybe<bool> WriteJSArray(Handle<JSArray> array) V8_WARN_UNUSED_RESULT; 128 void WriteJSDate(JSDate* date); 129 Maybe<bool> WriteJSValue(Handle<JSValue> value) V8_WARN_UNUSED_RESULT; 130 void WriteJSRegExp(JSRegExp* regexp); 131 Maybe<bool> WriteJSMap(Handle<JSMap> map) V8_WARN_UNUSED_RESULT; 132 Maybe<bool> WriteJSSet(Handle<JSSet> map) V8_WARN_UNUSED_RESULT; 133 Maybe<bool> WriteJSArrayBuffer(Handle<JSArrayBuffer> array_buffer) 134 V8_WARN_UNUSED_RESULT; 135 Maybe<bool> WriteJSArrayBufferView(JSArrayBufferView* array_buffer); 136 Maybe<bool> WriteWasmModule(Handle<WasmModuleObject> object) 137 V8_WARN_UNUSED_RESULT; 138 Maybe<bool> WriteWasmMemory(Handle<WasmMemoryObject> object) 139 V8_WARN_UNUSED_RESULT; 140 Maybe<bool> WriteHostObject(Handle<JSObject> object) V8_WARN_UNUSED_RESULT; 141 142 /* 143 * Reads the specified keys from the object and writes key-value pairs to the 144 * buffer. Returns the number of keys actually written, which may be smaller 145 * if some keys are not own properties when accessed. 146 */ 147 Maybe<uint32_t> WriteJSObjectPropertiesSlow( 148 Handle<JSObject> object, Handle<FixedArray> keys) V8_WARN_UNUSED_RESULT; 149 150 /* 151 * Asks the delegate to handle an error that occurred during data cloning, by 152 * throwing an exception appropriate for the host. 153 */ 154 void ThrowDataCloneError(MessageTemplate::Template template_index); 155 V8_NOINLINE void ThrowDataCloneError(MessageTemplate::Template template_index, 156 Handle<Object> arg0); 157 158 Maybe<bool> ThrowIfOutOfMemory(); 159 160 Isolate* const isolate_; 161 v8::ValueSerializer::Delegate* const delegate_; 162 bool treat_array_buffer_views_as_host_objects_ = false; 163 uint8_t* buffer_ = nullptr; 164 size_t buffer_size_ = 0; 165 size_t buffer_capacity_ = 0; 166 bool out_of_memory_ = false; 167 Zone zone_; 168 169 // To avoid extra lookups in the identity map, ID+1 is actually stored in the 170 // map (checking if the used identity is zero is the fast way of checking if 171 // the entry is new). 172 IdentityMap<uint32_t, ZoneAllocationPolicy> id_map_; 173 uint32_t next_id_ = 0; 174 175 // A similar map, for transferred array buffers. 176 IdentityMap<uint32_t, ZoneAllocationPolicy> array_buffer_transfer_map_; 177 178 DISALLOW_COPY_AND_ASSIGN(ValueSerializer); 179 }; 180 181 /* 182 * Deserializes values from data written with ValueSerializer, or a compatible 183 * implementation. 184 */ 185 class ValueDeserializer { 186 public: 187 ValueDeserializer(Isolate* isolate, Vector<const uint8_t> data, 188 v8::ValueDeserializer::Delegate* delegate); 189 ~ValueDeserializer(); 190 191 /* 192 * Runs version detection logic, which may fail if the format is invalid. 193 */ 194 Maybe<bool> ReadHeader() V8_WARN_UNUSED_RESULT; 195 196 /* 197 * Reads the underlying wire format version. Likely mostly to be useful to 198 * legacy code reading old wire format versions. Must be called after 199 * ReadHeader. 200 */ GetWireFormatVersion()201 uint32_t GetWireFormatVersion() const { return version_; } 202 203 /* 204 * Deserializes a V8 object from the buffer. 205 */ 206 MaybeHandle<Object> ReadObject() V8_WARN_UNUSED_RESULT; 207 208 /* 209 * Reads an object, consuming the entire buffer. 210 * 211 * This is required for the legacy "version 0" format, which did not allow 212 * reference deduplication, and instead relied on a "stack" model for 213 * deserializing, with the contents of objects and arrays provided first. 214 */ 215 MaybeHandle<Object> ReadObjectUsingEntireBufferForLegacyFormat() 216 V8_WARN_UNUSED_RESULT; 217 218 /* 219 * Accepts the array buffer corresponding to the one passed previously to 220 * ValueSerializer::TransferArrayBuffer. 221 */ 222 void TransferArrayBuffer(uint32_t transfer_id, 223 Handle<JSArrayBuffer> array_buffer); 224 225 /* 226 * Publicly exposed wire format writing methods. 227 * These are intended for use within the delegate's WriteHostObject method. 228 */ 229 bool ReadUint32(uint32_t* value) V8_WARN_UNUSED_RESULT; 230 bool ReadUint64(uint64_t* value) V8_WARN_UNUSED_RESULT; 231 bool ReadDouble(double* value) V8_WARN_UNUSED_RESULT; 232 bool ReadRawBytes(size_t length, const void** data) V8_WARN_UNUSED_RESULT; set_expect_inline_wasm(bool expect_inline_wasm)233 void set_expect_inline_wasm(bool expect_inline_wasm) { 234 expect_inline_wasm_ = expect_inline_wasm; 235 } 236 237 private: 238 // Reading the wire format. 239 Maybe<SerializationTag> PeekTag() const V8_WARN_UNUSED_RESULT; 240 void ConsumeTag(SerializationTag peeked_tag); 241 Maybe<SerializationTag> ReadTag() V8_WARN_UNUSED_RESULT; 242 template <typename T> 243 Maybe<T> ReadVarint() V8_WARN_UNUSED_RESULT; 244 template <typename T> 245 Maybe<T> ReadZigZag() V8_WARN_UNUSED_RESULT; 246 Maybe<double> ReadDouble() V8_WARN_UNUSED_RESULT; 247 Maybe<Vector<const uint8_t>> ReadRawBytes(int size) V8_WARN_UNUSED_RESULT; expect_inline_wasm()248 bool expect_inline_wasm() const { return expect_inline_wasm_; } 249 250 // Reads a string if it matches the one provided. 251 // Returns true if this was the case. Otherwise, nothing is consumed. 252 bool ReadExpectedString(Handle<String> expected) V8_WARN_UNUSED_RESULT; 253 254 // Like ReadObject, but skips logic for special cases in simulating the 255 // "stack machine". 256 MaybeHandle<Object> ReadObjectInternal() V8_WARN_UNUSED_RESULT; 257 258 // Reads a string intended to be part of a more complicated object. 259 // Before v12, these are UTF-8 strings. After, they can be any encoding 260 // permissible for a string (with the relevant tag). 261 MaybeHandle<String> ReadString() V8_WARN_UNUSED_RESULT; 262 263 // Reading V8 objects of specific kinds. 264 // The tag is assumed to have already been read. 265 MaybeHandle<BigInt> ReadBigInt() V8_WARN_UNUSED_RESULT; 266 MaybeHandle<String> ReadUtf8String() V8_WARN_UNUSED_RESULT; 267 MaybeHandle<String> ReadOneByteString() V8_WARN_UNUSED_RESULT; 268 MaybeHandle<String> ReadTwoByteString() V8_WARN_UNUSED_RESULT; 269 MaybeHandle<JSObject> ReadJSObject() V8_WARN_UNUSED_RESULT; 270 MaybeHandle<JSArray> ReadSparseJSArray() V8_WARN_UNUSED_RESULT; 271 MaybeHandle<JSArray> ReadDenseJSArray() V8_WARN_UNUSED_RESULT; 272 MaybeHandle<JSDate> ReadJSDate() V8_WARN_UNUSED_RESULT; 273 MaybeHandle<JSValue> ReadJSValue(SerializationTag tag) V8_WARN_UNUSED_RESULT; 274 MaybeHandle<JSRegExp> ReadJSRegExp() V8_WARN_UNUSED_RESULT; 275 MaybeHandle<JSMap> ReadJSMap() V8_WARN_UNUSED_RESULT; 276 MaybeHandle<JSSet> ReadJSSet() V8_WARN_UNUSED_RESULT; 277 MaybeHandle<JSArrayBuffer> ReadJSArrayBuffer(bool is_shared) 278 V8_WARN_UNUSED_RESULT; 279 MaybeHandle<JSArrayBuffer> ReadTransferredJSArrayBuffer() 280 V8_WARN_UNUSED_RESULT; 281 MaybeHandle<JSArrayBufferView> ReadJSArrayBufferView( 282 Handle<JSArrayBuffer> buffer) V8_WARN_UNUSED_RESULT; 283 MaybeHandle<JSObject> ReadWasmModule() V8_WARN_UNUSED_RESULT; 284 MaybeHandle<JSObject> ReadWasmModuleTransfer() V8_WARN_UNUSED_RESULT; 285 MaybeHandle<WasmMemoryObject> ReadWasmMemory() V8_WARN_UNUSED_RESULT; 286 MaybeHandle<JSObject> ReadHostObject() V8_WARN_UNUSED_RESULT; 287 288 /* 289 * Reads key-value pairs into the object until the specified end tag is 290 * encountered. If successful, returns the number of properties read. 291 */ 292 Maybe<uint32_t> ReadJSObjectProperties(Handle<JSObject> object, 293 SerializationTag end_tag, 294 bool can_use_transitions); 295 296 // Manipulating the map from IDs to reified objects. 297 bool HasObjectWithID(uint32_t id); 298 MaybeHandle<JSReceiver> GetObjectWithID(uint32_t id); 299 void AddObjectWithID(uint32_t id, Handle<JSReceiver> object); 300 301 Isolate* const isolate_; 302 v8::ValueDeserializer::Delegate* const delegate_; 303 const uint8_t* position_; 304 const uint8_t* const end_; 305 PretenureFlag pretenure_; 306 uint32_t version_ = 0; 307 uint32_t next_id_ = 0; 308 bool expect_inline_wasm_ = false; 309 310 // Always global handles. 311 Handle<FixedArray> id_map_; 312 MaybeHandle<SimpleNumberDictionary> array_buffer_transfer_map_; 313 314 DISALLOW_COPY_AND_ASSIGN(ValueDeserializer); 315 }; 316 317 } // namespace internal 318 } // namespace v8 319 320 #endif // V8_VALUE_SERIALIZER_H_ 321