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/stringprintf.h"
20 #include "base/unix_file/fd_file.h"
21 #include "common_compiler_test.h"
22 #include "elf_file.h"
23 #include "elf_file_impl.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 EXPECT_LT(static_cast<uintptr_t>(ART_BASE_ADDRESS), reinterpret_cast<uintptr_t>(addr)); \
45 if (expected_value == nullptr) { \
46 expected_value = addr; \
47 } \
48 EXPECT_EQ(expected_value, addr); \
49 EXPECT_EQ(expected_value, ef->FindDynamicSymbolAddress(symbol_name)); \
50 } while (false)
51
TEST_F(ElfWriterTest,dlsym)52 TEST_F(ElfWriterTest, dlsym) {
53 std::string elf_location = GetCoreOatLocation();
54 std::string elf_filename = GetSystemImageFilename(elf_location.c_str(), kRuntimeISA);
55 LOG(INFO) << "elf_filename=" << elf_filename;
56
57 UnreserveImageSpace();
58 void* dl_oatdata = nullptr;
59 void* dl_oatexec = nullptr;
60 void* dl_oatlastword = nullptr;
61
62 std::unique_ptr<File> file(OS::OpenFileForReading(elf_filename.c_str()));
63 ASSERT_TRUE(file.get() != nullptr);
64 {
65 std::string error_msg;
66 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(), false, false, &error_msg));
67 CHECK(ef.get() != nullptr) << error_msg;
68 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatdata, "oatdata", false);
69 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatexec, "oatexec", false);
70 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatlastword, "oatlastword", false);
71 }
72 {
73 std::string error_msg;
74 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(), false, false, &error_msg));
75 CHECK(ef.get() != nullptr) << error_msg;
76 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatdata, "oatdata", true);
77 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatexec, "oatexec", true);
78 EXPECT_ELF_FILE_ADDRESS(ef, dl_oatlastword, "oatlastword", true);
79 }
80 {
81 std::string error_msg;
82 std::unique_ptr<ElfFile> ef(ElfFile::Open(file.get(), false, true, &error_msg));
83 CHECK(ef.get() != nullptr) << error_msg;
84 CHECK(ef->Load(false, &error_msg)) << error_msg;
85 EXPECT_EQ(dl_oatdata, ef->FindDynamicSymbolAddress("oatdata"));
86 EXPECT_EQ(dl_oatexec, ef->FindDynamicSymbolAddress("oatexec"));
87 EXPECT_EQ(dl_oatlastword, ef->FindDynamicSymbolAddress("oatlastword"));
88 }
89 }
90
TEST_F(ElfWriterTest,EncodeDecodeOatPatches)91 TEST_F(ElfWriterTest, EncodeDecodeOatPatches) {
92 const std::vector<std::vector<uintptr_t>> test_data {
93 { 0, 4, 8, 15, 128, 200 },
94 { 8, 8 + 127 },
95 { 8, 8 + 128 },
96 { },
97 };
98 for (const auto& patch_locations : test_data) {
99 constexpr int32_t delta = 0x11235813;
100
101 // Encode patch locations.
102 std::vector<uint8_t> oat_patches;
103 ElfWriterQuick32::EncodeOatPatches(patch_locations, &oat_patches);
104
105 // Create buffer to be patched.
106 std::vector<uint8_t> initial_data(256);
107 for (size_t i = 0; i < initial_data.size(); i++) {
108 initial_data[i] = i;
109 }
110
111 // Patch manually.
112 std::vector<uint8_t> expected = initial_data;
113 for (uintptr_t location : patch_locations) {
114 typedef __attribute__((__aligned__(1))) uint32_t UnalignedAddress;
115 *reinterpret_cast<UnalignedAddress*>(expected.data() + location) += delta;
116 }
117
118 // Decode and apply patch locations.
119 std::vector<uint8_t> actual = initial_data;
120 ElfFileImpl32::ApplyOatPatches(
121 oat_patches.data(), oat_patches.data() + oat_patches.size(), delta,
122 actual.data(), actual.data() + actual.size());
123
124 EXPECT_EQ(expected, actual);
125 }
126 }
127
128 } // namespace art
129