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/file_utils.h"
20 #include "base/unix_file/fd_file.h"
21 #include "base/utils.h"
22 #include "common_compiler_test.h"
23 #include "elf_file.h"
24 #include "elf_file_impl.h"
25 #include "elf_writer_quick.h"
26 #include "linker/elf_builder.h"
27 #include "oat.h"
28
29 namespace art {
30 namespace linker {
31
32 class ElfWriterTest : public CommonCompilerTest {
33 protected:
SetUp()34 virtual void SetUp() {
35 ReserveImageSpace();
36 CommonCompilerTest::SetUp();
37 }
38 };
39
40 #define EXPECT_ELF_FILE_ADDRESS(ef, expected_value, symbol_name, build_map) \
41 do { \
42 void* addr = reinterpret_cast<void*>((ef)->FindSymbolAddress(SHT_DYNSYM, \
43 symbol_name, \
44 build_map)); \
45 EXPECT_NE(nullptr, addr); \
46 if ((expected_value) == nullptr) { \
47 (expected_value) = addr; \
48 } \
49 EXPECT_EQ(expected_value, addr); \
50 EXPECT_EQ(expected_value, (ef)->FindDynamicSymbolAddress(symbol_name)); \
51 } while (false)
52
TEST_F(ElfWriterTest,dlsym)53 TEST_F(ElfWriterTest, dlsym) {
54 std::string elf_location = GetCoreOatLocation();
55 std::string elf_filename = GetSystemImageFilename(elf_location.c_str(), kRuntimeISA);
56 LOG(INFO) << "elf_filename=" << elf_filename;
57
58 UnreserveImageSpace();
59 void* dl_oatdata = nullptr;
60 void* dl_oatexec = nullptr;
61 void* dl_oatlastword = nullptr;
62
63 std::unique_ptr<File> file(OS::OpenFileForReading(elf_filename.c_str()));
64 ASSERT_TRUE(file.get() != nullptr) << elf_filename;
65 {
66 std::string error_msg;
67 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(),
68 false,
69 false,
70 /*low_4gb*/false,
71 &error_msg));
72 CHECK(ef.get() != nullptr) << error_msg;
73 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatdata, "oatdata", false);
74 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatexec, "oatexec", false);
75 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatlastword, "oatlastword", false);
76 }
77 {
78 std::string error_msg;
79 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(),
80 false,
81 false,
82 /*low_4gb*/false,
83 &error_msg));
84 CHECK(ef.get() != nullptr) << error_msg;
85 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatdata, "oatdata", true);
86 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatexec, "oatexec", true);
87 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatlastword, "oatlastword", true);
88 }
89 {
90 uint8_t* base = reinterpret_cast<uint8_t*>(ART_BASE_ADDRESS);
91 std::string error_msg;
92 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(),
93 false,
94 true,
95 /*low_4gb*/false,
96 &error_msg,
97 base));
98 CHECK(ef.get() != nullptr) << error_msg;
99 CHECK(ef->Load(file.get(), false, /*low_4gb*/false, &error_msg)) << error_msg;
100 EXPECT_EQ(reinterpret_cast<uintptr_t>(dl_oatdata) + reinterpret_cast<uintptr_t>(base),
101 reinterpret_cast<uintptr_t>(ef->FindDynamicSymbolAddress("oatdata")));
102 EXPECT_EQ(reinterpret_cast<uintptr_t>(dl_oatexec) + reinterpret_cast<uintptr_t>(base),
103 reinterpret_cast<uintptr_t>(ef->FindDynamicSymbolAddress("oatexec")));
104 EXPECT_EQ(reinterpret_cast<uintptr_t>(dl_oatlastword) + reinterpret_cast<uintptr_t>(base),
105 reinterpret_cast<uintptr_t>(ef->FindDynamicSymbolAddress("oatlastword")));
106 }
107 }
108
TEST_F(ElfWriterTest,CheckBuildIdPresent)109 TEST_F(ElfWriterTest, CheckBuildIdPresent) {
110 std::string elf_location = GetCoreOatLocation();
111 std::string elf_filename = GetSystemImageFilename(elf_location.c_str(), kRuntimeISA);
112 LOG(INFO) << "elf_filename=" << elf_filename;
113
114 std::unique_ptr<File> file(OS::OpenFileForReading(elf_filename.c_str()));
115 ASSERT_TRUE(file.get() != nullptr);
116 {
117 std::string error_msg;
118 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(),
119 false,
120 false,
121 /*low_4gb*/false,
122 &error_msg));
123 CHECK(ef.get() != nullptr) << error_msg;
124 EXPECT_TRUE(ef->HasSection(".note.gnu.build-id"));
125 }
126 }
127
TEST_F(ElfWriterTest,EncodeDecodeOatPatches)128 TEST_F(ElfWriterTest, EncodeDecodeOatPatches) {
129 const std::vector<std::vector<uintptr_t>> test_data {
130 { 0, 4, 8, 15, 128, 200 },
131 { 8, 8 + 127 },
132 { 8, 8 + 128 },
133 { },
134 };
135 for (const auto& patch_locations : test_data) {
136 constexpr int32_t delta = 0x11235813;
137
138 // Encode patch locations.
139 std::vector<uint8_t> oat_patches;
140 ElfBuilder<ElfTypes32>::EncodeOatPatches(ArrayRef<const uintptr_t>(patch_locations),
141 &oat_patches);
142
143 // Create buffer to be patched.
144 std::vector<uint8_t> initial_data(256);
145 for (size_t i = 0; i < initial_data.size(); i++) {
146 initial_data[i] = i;
147 }
148
149 // Patch manually.
150 std::vector<uint8_t> expected = initial_data;
151 for (uintptr_t location : patch_locations) {
152 typedef __attribute__((__aligned__(1))) uint32_t UnalignedAddress;
153 *reinterpret_cast<UnalignedAddress*>(expected.data() + location) += delta;
154 }
155
156 // Decode and apply patch locations.
157 std::vector<uint8_t> actual = initial_data;
158 ElfFileImpl32::ApplyOatPatches(
159 oat_patches.data(), oat_patches.data() + oat_patches.size(), delta,
160 actual.data(), actual.data() + actual.size());
161
162 EXPECT_EQ(expected, actual);
163 }
164 }
165
166 } // namespace linker
167 } // namespace art
168