1 /* Copyright (C) 2016 The Android Open Source Project 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 3 * 4 * This file implements interfaces from the file jvmti.h. This implementation 5 * is licensed under the same terms as the file jvmti.h. The 6 * copyright and license information for the file jvmti.h follows. 7 * 8 * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved. 9 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 10 * 11 * This code is free software; you can redistribute it and/or modify it 12 * under the terms of the GNU General Public License version 2 only, as 13 * published by the Free Software Foundation. Oracle designates this 14 * particular file as subject to the "Classpath" exception as provided 15 * by Oracle in the LICENSE file that accompanied this code. 16 * 17 * This code is distributed in the hope that it will be useful, but WITHOUT 18 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 19 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 20 * version 2 for more details (a copy is included in the LICENSE file that 21 * accompanied this code). 22 * 23 * You should have received a copy of the GNU General Public License version 24 * 2 along with this work; if not, write to the Free Software Foundation, 25 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 26 * 27 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 28 * or visit www.oracle.com if you need additional information or have any 29 * questions. 30 */ 31 32 #ifndef ART_OPENJDKJVMTI_TI_REDEFINE_H_ 33 #define ART_OPENJDKJVMTI_TI_REDEFINE_H_ 34 35 #include <string> 36 37 #include <jni.h> 38 39 #include "art_jvmti.h" 40 #include "base/array_ref.h" 41 #include "base/globals.h" 42 #include "jni/jni_env_ext-inl.h" 43 #include "jvmti.h" 44 #include "mirror/array.h" 45 #include "mirror/class.h" 46 #include "obj_ptr.h" 47 48 namespace art { 49 namespace dex { 50 struct ClassDef; 51 } // namespace dex 52 class DexFile; 53 } // namespace art 54 55 namespace openjdkjvmti { 56 57 class ArtClassDefinition; 58 class RedefinitionDataHolder; 59 class RedefinitionDataIter; 60 61 // Class that can redefine a single class's methods. 62 class Redefiner { 63 public: 64 // Redefine the given classes with the given dex data. Note this function does not take ownership 65 // of the dex_data pointers. It is not used after this call however and may be freed if desired. 66 // The caller is responsible for freeing it. The runtime makes its own copy of the data. This 67 // function does not call the transformation events. 68 static jvmtiError RedefineClassesDirect(ArtJvmTiEnv* env, 69 art::Runtime* runtime, 70 art::Thread* self, 71 const std::vector<ArtClassDefinition>& definitions, 72 /*out*/std::string* error_msg); 73 74 // Redefine the given classes with the given dex data. Note this function does not take ownership 75 // of the dex_data pointers. It is not used after this call however and may be freed if desired. 76 // The caller is responsible for freeing it. The runtime makes its own copy of the data. 77 static jvmtiError RedefineClasses(ArtJvmTiEnv* env, 78 EventHandler* event_handler, 79 art::Runtime* runtime, 80 art::Thread* self, 81 jint class_count, 82 const jvmtiClassDefinition* definitions, 83 /*out*/std::string* error_msg); 84 85 static jvmtiError IsModifiableClass(jvmtiEnv* env, jclass klass, jboolean* is_redefinable); 86 87 static art::MemMap MoveDataToMemMap(const std::string& original_location, 88 art::ArrayRef<const unsigned char> data, 89 std::string* error_msg); 90 91 // Helper for checking if redefinition/retransformation is allowed. 92 static jvmtiError GetClassRedefinitionError(jclass klass, /*out*/std::string* error_msg) 93 REQUIRES(!art::Locks::mutator_lock_); 94 95 private: 96 class ClassRedefinition { 97 public: 98 ClassRedefinition(Redefiner* driver, 99 jclass klass, 100 const art::DexFile* redefined_dex_file, 101 const char* class_sig, 102 art::ArrayRef<const unsigned char> orig_dex_file) 103 REQUIRES_SHARED(art::Locks::mutator_lock_); 104 105 // NO_THREAD_SAFETY_ANALYSIS so we can unlock the class in the destructor. 106 ~ClassRedefinition() NO_THREAD_SAFETY_ANALYSIS; 107 108 // Move constructor so we can put these into a vector. 109 ClassRedefinition(ClassRedefinition&& other) 110 : driver_(other.driver_), 111 klass_(other.klass_), 112 dex_file_(std::move(other.dex_file_)), 113 class_sig_(std::move(other.class_sig_)), 114 original_dex_file_(other.original_dex_file_) { 115 other.driver_ = nullptr; 116 } 117 118 art::ObjPtr<art::mirror::Class> GetMirrorClass() REQUIRES_SHARED(art::Locks::mutator_lock_); 119 art::ObjPtr<art::mirror::ClassLoader> GetClassLoader() 120 REQUIRES_SHARED(art::Locks::mutator_lock_); 121 122 const art::DexFile& GetDexFile() { 123 return *dex_file_; 124 } 125 126 art::mirror::DexCache* CreateNewDexCache(art::Handle<art::mirror::ClassLoader> loader) 127 REQUIRES_SHARED(art::Locks::mutator_lock_); 128 129 // This may return nullptr with a OOME pending if allocation fails. 130 art::mirror::Object* AllocateOrGetOriginalDexFile() 131 REQUIRES_SHARED(art::Locks::mutator_lock_); 132 133 void RecordFailure(jvmtiError e, const std::string& err) { 134 driver_->RecordFailure(e, class_sig_, err); 135 } 136 137 bool FinishRemainingAllocations(/*out*/RedefinitionDataIter* cur_data) 138 REQUIRES_SHARED(art::Locks::mutator_lock_); 139 140 bool AllocateAndRememberNewDexFileCookie( 141 art::Handle<art::mirror::ClassLoader> source_class_loader, 142 art::Handle<art::mirror::Object> dex_file_obj, 143 /*out*/RedefinitionDataIter* cur_data) 144 REQUIRES_SHARED(art::Locks::mutator_lock_); 145 146 void FindAndAllocateObsoleteMethods(art::ObjPtr<art::mirror::Class> art_klass) 147 REQUIRES(art::Locks::mutator_lock_); 148 149 // Checks that the dex file contains only the single expected class and that the top-level class 150 // data has not been modified in an incompatible manner. 151 bool CheckClass() REQUIRES_SHARED(art::Locks::mutator_lock_); 152 153 // Checks that the contained class can be successfully verified. 154 bool CheckVerification(const RedefinitionDataIter& holder) 155 REQUIRES_SHARED(art::Locks::mutator_lock_); 156 157 // Preallocates all needed allocations in klass so that we can pause execution safely. 158 bool EnsureClassAllocationsFinished(/*out*/RedefinitionDataIter* data) 159 REQUIRES_SHARED(art::Locks::mutator_lock_); 160 161 // This will check that no constraints are violated (more than 1 class in dex file, any changes 162 // in number/declaration of methods & fields, changes in access flags, etc.) 163 bool CheckRedefinitionIsValid() REQUIRES_SHARED(art::Locks::mutator_lock_); 164 165 // Checks that the class can even be redefined. 166 bool CheckRedefinable() REQUIRES_SHARED(art::Locks::mutator_lock_); 167 168 // Checks that the dex file does not add/remove methods, or change their modifiers or types. 169 bool CheckSameMethods() REQUIRES_SHARED(art::Locks::mutator_lock_); 170 171 // Checks that the dex file does not modify fields types or modifiers. 172 bool CheckSameFields() REQUIRES_SHARED(art::Locks::mutator_lock_); 173 174 void UpdateJavaDexFile(art::ObjPtr<art::mirror::Object> java_dex_file, 175 art::ObjPtr<art::mirror::LongArray> new_cookie) 176 REQUIRES(art::Locks::mutator_lock_); 177 178 void UpdateFields(art::ObjPtr<art::mirror::Class> mclass) 179 REQUIRES(art::Locks::mutator_lock_); 180 181 void UpdateMethods(art::ObjPtr<art::mirror::Class> mclass, 182 const art::dex::ClassDef& class_def) 183 REQUIRES(art::Locks::mutator_lock_); 184 185 void UpdateClass(art::ObjPtr<art::mirror::Class> mclass, 186 art::ObjPtr<art::mirror::DexCache> new_dex_cache, 187 art::ObjPtr<art::mirror::Object> original_dex_file) 188 REQUIRES(art::Locks::mutator_lock_); 189 190 void RestoreObsoleteMethodMapsIfUnneeded(const RedefinitionDataIter* cur_data) 191 REQUIRES(art::Locks::mutator_lock_); 192 193 void ReleaseDexFile() REQUIRES_SHARED(art::Locks::mutator_lock_); 194 195 void UnregisterBreakpoints() REQUIRES_SHARED(art::Locks::mutator_lock_); 196 // This should be done with all threads suspended. 197 void UnregisterJvmtiBreakpoints() REQUIRES_SHARED(art::Locks::mutator_lock_); 198 199 private: 200 Redefiner* driver_; 201 jclass klass_; 202 std::unique_ptr<const art::DexFile> dex_file_; 203 std::string class_sig_; 204 art::ArrayRef<const unsigned char> original_dex_file_; 205 }; 206 207 ArtJvmTiEnv* env_; 208 jvmtiError result_; 209 art::Runtime* runtime_; 210 art::Thread* self_; 211 std::vector<ClassRedefinition> redefinitions_; 212 // Kept as a jclass since we have weird run-state changes that make keeping it around as a 213 // mirror::Class difficult and confusing. 214 std::string* error_msg_; 215 216 Redefiner(ArtJvmTiEnv* env, 217 art::Runtime* runtime, 218 art::Thread* self, 219 std::string* error_msg) 220 : env_(env), 221 result_(ERR(INTERNAL)), 222 runtime_(runtime), 223 self_(self), 224 redefinitions_(), 225 error_msg_(error_msg) { } 226 227 jvmtiError AddRedefinition(ArtJvmTiEnv* env, const ArtClassDefinition& def) 228 REQUIRES_SHARED(art::Locks::mutator_lock_); 229 230 static jvmtiError GetClassRedefinitionError(art::Handle<art::mirror::Class> klass, 231 /*out*/std::string* error_msg) 232 REQUIRES_SHARED(art::Locks::mutator_lock_); 233 234 jvmtiError Run() REQUIRES_SHARED(art::Locks::mutator_lock_); 235 236 bool CheckAllRedefinitionAreValid() REQUIRES_SHARED(art::Locks::mutator_lock_); 237 bool CheckAllClassesAreVerified(RedefinitionDataHolder& holder) 238 REQUIRES_SHARED(art::Locks::mutator_lock_); 239 bool EnsureAllClassAllocationsFinished(RedefinitionDataHolder& holder) 240 REQUIRES_SHARED(art::Locks::mutator_lock_); 241 bool FinishAllRemainingAllocations(RedefinitionDataHolder& holder) 242 REQUIRES_SHARED(art::Locks::mutator_lock_); 243 void ReleaseAllDexFiles() REQUIRES_SHARED(art::Locks::mutator_lock_); 244 void UnregisterAllBreakpoints() REQUIRES_SHARED(art::Locks::mutator_lock_); 245 // Restores the old obsolete methods maps if it turns out they weren't needed (ie there were no 246 // new obsolete methods). 247 void RestoreObsoleteMethodMapsIfUnneeded(RedefinitionDataHolder& holder) 248 REQUIRES(art::Locks::mutator_lock_); 249 250 void RecordFailure(jvmtiError result, const std::string& class_sig, const std::string& error_msg); 251 void RecordFailure(jvmtiError result, const std::string& error_msg) { 252 RecordFailure(result, "NO CLASS", error_msg); 253 } 254 255 friend struct CallbackCtx; 256 friend class RedefinitionDataHolder; 257 friend class RedefinitionDataIter; 258 }; 259 260 } // namespace openjdkjvmti 261 262 #endif // ART_OPENJDKJVMTI_TI_REDEFINE_H_ 263
