1 /* Copyright (C) 2017 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 #include "ti_class_loader-inl.h"
33
34 #include <limits>
35
36 #include <android-base/logging.h>
37 #include <android-base/stringprintf.h>
38
39 #include "art_field-inl.h"
40 #include "art_jvmti.h"
41 #include "dex/dex_file.h"
42 #include "dex/dex_file_types.h"
43 #include "events-inl.h"
44 #include "gc/allocation_listener.h"
45 #include "gc/heap.h"
46 #include "instrumentation.h"
47 #include "jit/jit.h"
48 #include "jit/jit_code_cache.h"
49 #include "jni/jni_env_ext-inl.h"
50 #include "jvmti_allocator.h"
51 #include "mirror/array-alloc-inl.h"
52 #include "mirror/array-inl.h"
53 #include "mirror/class.h"
54 #include "mirror/class_ext.h"
55 #include "mirror/object.h"
56 #include "nativehelper/scoped_local_ref.h"
57 #include "object_lock.h"
58 #include "runtime.h"
59 #include "transform.h"
60 #include "well_known_classes-inl.h"
61
62 namespace openjdkjvmti {
63
AddToClassLoader(art::Thread * self,art::Handle<art::mirror::ClassLoader> loader,const art::DexFile * dex_file)64 bool ClassLoaderHelper::AddToClassLoader(art::Thread* self,
65 art::Handle<art::mirror::ClassLoader> loader,
66 const art::DexFile* dex_file) {
67 art::StackHandleScope<3> hs(self);
68 if (art::ClassLinker::IsBootClassLoader(loader.Get())) {
69 art::Runtime::Current()->AppendToBootClassPath(
70 dex_file->GetLocation(), dex_file->GetLocation(), {dex_file});
71 return true;
72 }
73 art::Handle<art::mirror::Object> java_dex_file_obj(
74 hs.NewHandle(FindSourceDexFileObject(self, loader)));
75 if (java_dex_file_obj.IsNull()) {
76 return false;
77 }
78 art::Handle<art::mirror::LongArray> old_cookie(hs.NewHandle(GetDexFileCookie(java_dex_file_obj)));
79 art::Handle<art::mirror::LongArray> cookie(hs.NewHandle(
80 AllocateNewDexFileCookie(self, old_cookie, dex_file)));
81 if (cookie.IsNull()) {
82 return false;
83 }
84 art::ScopedAssertNoThreadSuspension nts("Replacing cookie fields in j.l.DexFile object");
85 UpdateJavaDexFile(java_dex_file_obj.Get(), cookie.Get());
86 return true;
87 }
88
UpdateJavaDexFile(art::ObjPtr<art::mirror::Object> java_dex_file,art::ObjPtr<art::mirror::LongArray> new_cookie)89 void ClassLoaderHelper::UpdateJavaDexFile(art::ObjPtr<art::mirror::Object> java_dex_file,
90 art::ObjPtr<art::mirror::LongArray> new_cookie) {
91 art::ArtField* internal_cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField(
92 "mInternalCookie", "Ljava/lang/Object;");
93 art::ArtField* cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField(
94 "mCookie", "Ljava/lang/Object;");
95 CHECK(internal_cookie_field != nullptr);
96 art::ObjPtr<art::mirror::LongArray> orig_cookie(
97 cookie_field->GetObject(java_dex_file)->AsLongArray());
98 internal_cookie_field->SetObject<false>(java_dex_file, new_cookie);
99 if (!orig_cookie.IsNull()) {
100 cookie_field->SetObject<false>(java_dex_file, new_cookie);
101 }
102 }
103
GetDexFileCookie(art::Handle<art::mirror::Object> java_dex_file_obj)104 art::ObjPtr<art::mirror::LongArray> ClassLoaderHelper::GetDexFileCookie(
105 art::Handle<art::mirror::Object> java_dex_file_obj) {
106 // mCookie is nulled out if the DexFile has been closed but mInternalCookie sticks around until
107 // the object is finalized. Since they always point to the same array if mCookie is not null we
108 // just use the mInternalCookie field. We will update one or both of these fields later.
109 art::ArtField* internal_cookie_field = java_dex_file_obj->GetClass()->FindDeclaredInstanceField(
110 "mInternalCookie", "Ljava/lang/Object;");
111 // TODO Add check that mCookie is either null or same as mInternalCookie
112 CHECK(internal_cookie_field != nullptr);
113 return internal_cookie_field->GetObject(java_dex_file_obj.Get())->AsLongArray();
114 }
115
AllocateNewDexFileCookie(art::Thread * self,art::Handle<art::mirror::LongArray> cookie,const art::DexFile * dex_file)116 art::ObjPtr<art::mirror::LongArray> ClassLoaderHelper::AllocateNewDexFileCookie(
117 art::Thread* self,
118 art::Handle<art::mirror::LongArray> cookie,
119 const art::DexFile* dex_file) {
120 art::StackHandleScope<1> hs(self);
121 CHECK(cookie != nullptr);
122 CHECK_GE(cookie->GetLength(), 1);
123 art::Handle<art::mirror::LongArray> new_cookie(
124 hs.NewHandle(art::mirror::LongArray::Alloc(self, cookie->GetLength() + 1)));
125 if (new_cookie == nullptr) {
126 self->AssertPendingOOMException();
127 return nullptr;
128 }
129 // Copy the oat-dex field at the start.
130 new_cookie->SetWithoutChecks<false>(0, cookie->GetWithoutChecks(0));
131 // This must match the casts in runtime/native/dalvik_system_DexFile.cc:ConvertDexFilesToJavaArray
132 new_cookie->SetWithoutChecks<false>(
133 1, static_cast<int64_t>(reinterpret_cast<uintptr_t>(dex_file)));
134 new_cookie->Memcpy(2, cookie.Get(), 1, cookie->GetLength() - 1);
135 return new_cookie.Get();
136 }
137
GetDexElementList(art::Thread * self,art::Handle<art::mirror::ClassLoader> loader)138 art::ObjPtr<art::mirror::ObjectArray<art::mirror::Object>> ClassLoaderHelper::GetDexElementList(
139 art::Thread* self,
140 art::Handle<art::mirror::ClassLoader> loader) {
141 art::StackHandleScope<4> hs(self);
142
143 art::Handle<art::mirror::Class> base_dex_loader_class =
144 hs.NewHandle(art::WellKnownClasses::dalvik_system_BaseDexClassLoader.Get());
145
146 // Get all the ArtFields so we can look in the BaseDexClassLoader
147 art::ArtField* path_list_field =
148 art::WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList;
149 art::ArtField* dex_path_list_element_field =
150 art::WellKnownClasses::dalvik_system_DexPathList_dexElements;
151
152 // Check if loader is a BaseDexClassLoader
153 art::Handle<art::mirror::Class> loader_class(hs.NewHandle(loader->GetClass()));
154 // Currently only base_dex_loader is allowed to actually define classes but if this changes in the
155 // future we should make sure to support all class loader types.
156 if (!loader_class->IsSubClass(base_dex_loader_class.Get())) {
157 LOG(ERROR) << "The classloader " << loader_class->PrettyClass() << " is not a "
158 << base_dex_loader_class->PrettyClass() << " which is currently the only "
159 << "supported class loader type!";
160 return nullptr;
161 }
162 // Start navigating the fields of the loader (now known to be a BaseDexClassLoader derivative)
163 art::Handle<art::mirror::Object> path_list(
164 hs.NewHandle(path_list_field->GetObject(loader.Get())));
165 CHECK(path_list != nullptr);
166 art::ObjPtr<art::mirror::ObjectArray<art::mirror::Object>> dex_elements_list =
167 dex_path_list_element_field->GetObject(path_list.Get())->AsObjectArray<art::mirror::Object>();
168 return dex_elements_list;
169 }
170
171 // TODO This should return the actual source java.lang.DexFile object for the klass being loaded.
FindSourceDexFileObject(art::Thread * self,art::Handle<art::mirror::ClassLoader> loader)172 art::ObjPtr<art::mirror::Object> ClassLoaderHelper::FindSourceDexFileObject(
173 art::Thread* self, art::Handle<art::mirror::ClassLoader> loader) {
174 art::ObjPtr<art::mirror::Object> res = nullptr;
175 VisitDexFileObjects(self,
176 loader,
177 [&] (art::ObjPtr<art::mirror::Object> dex_file) {
178 res = dex_file;
179 // Just stop at the first one.
180 // TODO It would be cleaner to put the art::DexFile into the
181 // dalvik.system.DexFile the class comes from but it is more annoying
182 // because we would need to find this class. It is not necessary for proper
183 // function since we just need to be in front of the classes old dex file in
184 // the path.
185 return false;
186 });
187 return res;
188 }
189
190 } // namespace openjdkjvmti
191