1 /*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "elf_file.h"
18
19 #include "base/unix_file/fd_file.h"
20 #include "common_compiler_test.h"
21 #include "elf_file.h"
22 #include "elf_file_impl.h"
23 #include "elf_builder.h"
24 #include "elf_writer_quick.h"
25 #include "oat.h"
26 #include "utils.h"
27
28 namespace art {
29
30 class ElfWriterTest : public CommonCompilerTest {
31 protected:
SetUp()32 virtual void SetUp() {
33 ReserveImageSpace();
34 CommonCompilerTest::SetUp();
35 }
36 };
37
38 #define EXPECT_ELF_FILE_ADDRESS(ef, expected_value, symbol_name, build_map) \
39 do { \
40 void* addr = reinterpret_cast<void*>((ef)->FindSymbolAddress(SHT_DYNSYM, \
41 symbol_name, \
42 build_map)); \
43 EXPECT_NE(nullptr, addr); \
44 if ((expected_value) == nullptr) { \
45 (expected_value) = addr; \
46 } \
47 EXPECT_EQ(expected_value, addr); \
48 EXPECT_EQ(expected_value, (ef)->FindDynamicSymbolAddress(symbol_name)); \
49 } while (false)
50
TEST_F(ElfWriterTest,dlsym)51 TEST_F(ElfWriterTest, dlsym) {
52 std::string elf_location = GetCoreOatLocation();
53 std::string elf_filename = GetSystemImageFilename(elf_location.c_str(), kRuntimeISA);
54 LOG(INFO) << "elf_filename=" << elf_filename;
55
56 UnreserveImageSpace();
57 void* dl_oatdata = nullptr;
58 void* dl_oatexec = nullptr;
59 void* dl_oatlastword = nullptr;
60
61 std::unique_ptr<File> file(OS::OpenFileForReading(elf_filename.c_str()));
62 ASSERT_TRUE(file.get() != nullptr) << elf_filename;
63 {
64 std::string error_msg;
65 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(),
66 false,
67 false,
68 /*low_4gb*/false,
69 &error_msg));
70 CHECK(ef.get() != nullptr) << error_msg;
71 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatdata, "oatdata", false);
72 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatexec, "oatexec", false);
73 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatlastword, "oatlastword", false);
74 }
75 {
76 std::string error_msg;
77 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(),
78 false,
79 false,
80 /*low_4gb*/false,
81 &error_msg));
82 CHECK(ef.get() != nullptr) << error_msg;
83 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatdata, "oatdata", true);
84 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatexec, "oatexec", true);
85 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatlastword, "oatlastword", true);
86 }
87 {
88 uint8_t* base = reinterpret_cast<uint8_t*>(ART_BASE_ADDRESS);
89 std::string error_msg;
90 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(),
91 false,
92 true,
93 /*low_4gb*/false,
94 &error_msg,
95 base));
96 CHECK(ef.get() != nullptr) << error_msg;
97 CHECK(ef->Load(file.get(), false, /*low_4gb*/false, &error_msg)) << error_msg;
98 EXPECT_EQ(reinterpret_cast<uintptr_t>(dl_oatdata) + reinterpret_cast<uintptr_t>(base),
99 reinterpret_cast<uintptr_t>(ef->FindDynamicSymbolAddress("oatdata")));
100 EXPECT_EQ(reinterpret_cast<uintptr_t>(dl_oatexec) + reinterpret_cast<uintptr_t>(base),
101 reinterpret_cast<uintptr_t>(ef->FindDynamicSymbolAddress("oatexec")));
102 EXPECT_EQ(reinterpret_cast<uintptr_t>(dl_oatlastword) + reinterpret_cast<uintptr_t>(base),
103 reinterpret_cast<uintptr_t>(ef->FindDynamicSymbolAddress("oatlastword")));
104 }
105 }
106
TEST_F(ElfWriterTest,CheckBuildIdPresent)107 TEST_F(ElfWriterTest, CheckBuildIdPresent) {
108 std::string elf_location = GetCoreOatLocation();
109 std::string elf_filename = GetSystemImageFilename(elf_location.c_str(), kRuntimeISA);
110 LOG(INFO) << "elf_filename=" << elf_filename;
111
112 std::unique_ptr<File> file(OS::OpenFileForReading(elf_filename.c_str()));
113 ASSERT_TRUE(file.get() != nullptr);
114 {
115 std::string error_msg;
116 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(),
117 false,
118 false,
119 /*low_4gb*/false,
120 &error_msg));
121 CHECK(ef.get() != nullptr) << error_msg;
122 EXPECT_TRUE(ef->HasSection(".note.gnu.build-id"));
123 }
124 }
125
TEST_F(ElfWriterTest,EncodeDecodeOatPatches)126 TEST_F(ElfWriterTest, EncodeDecodeOatPatches) {
127 const std::vector<std::vector<uintptr_t>> test_data {
128 { 0, 4, 8, 15, 128, 200 },
129 { 8, 8 + 127 },
130 { 8, 8 + 128 },
131 { },
132 };
133 for (const auto& patch_locations : test_data) {
134 constexpr int32_t delta = 0x11235813;
135
136 // Encode patch locations.
137 std::vector<uint8_t> oat_patches;
138 ElfBuilder<ElfTypes32>::EncodeOatPatches(ArrayRef<const uintptr_t>(patch_locations),
139 &oat_patches);
140
141 // Create buffer to be patched.
142 std::vector<uint8_t> initial_data(256);
143 for (size_t i = 0; i < initial_data.size(); i++) {
144 initial_data[i] = i;
145 }
146
147 // Patch manually.
148 std::vector<uint8_t> expected = initial_data;
149 for (uintptr_t location : patch_locations) {
150 typedef __attribute__((__aligned__(1))) uint32_t UnalignedAddress;
151 *reinterpret_cast<UnalignedAddress*>(expected.data() + location) += delta;
152 }
153
154 // Decode and apply patch locations.
155 std::vector<uint8_t> actual = initial_data;
156 ElfFileImpl32::ApplyOatPatches(
157 oat_patches.data(), oat_patches.data() + oat_patches.size(), delta,
158 actual.data(), actual.data() + actual.size());
159
160 EXPECT_EQ(expected, actual);
161 }
162 }
163
164 } // namespace art
165