1 /*
2 * Copyright (c) 2024-2024 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16 #include "elf_sign_block.h"
17
18 namespace OHOS {
19 namespace SignatureTools {
20
ElfSignBlock()21 ElfSignBlock::ElfSignBlock()
22 {
23 type = MERKLE_TREE_INLINED;
24 }
25
ElfSignBlock(int32_t paddingSize,const std::vector<int8_t> & merkleTreeData,const FsVerityDescriptorWithSign & descriptorWithSign)26 ElfSignBlock::ElfSignBlock(int32_t paddingSize, const std::vector<int8_t> &merkleTreeData,
27 const FsVerityDescriptorWithSign &descriptorWithSign)
28 {
29 std::vector<int8_t> inMerkleTreeData;
30 if (!merkleTreeData.empty()) {
31 inMerkleTreeData = merkleTreeData;
32 }
33 treeLength = paddingSize + inMerkleTreeData.size();
34 merkleTreeWithPadding.resize(treeLength);
35 std::copy(inMerkleTreeData.begin(), inMerkleTreeData.end(), merkleTreeWithPadding.begin() + paddingSize);
36 this->descriptorWithSign = descriptorWithSign;
37 }
38
Size()39 int32_t ElfSignBlock::Size()
40 {
41 int tmpVariable = 2;
42 return FsVerityDescriptorWithSign::INTEGER_BYTES * tmpVariable
43 + merkleTreeWithPadding.size() + descriptorWithSign.Size();
44 }
45
GetMerkleTreeWithPadding()46 std::vector<int8_t>& ElfSignBlock::GetMerkleTreeWithPadding()
47 {
48 return merkleTreeWithPadding;
49 }
50
GetDataSize()51 int64_t ElfSignBlock::GetDataSize()
52 {
53 return descriptorWithSign.GetFsVerityDescriptor().GetFileSize();
54 }
55
GetTreeOffset()56 int64_t ElfSignBlock::GetTreeOffset()
57 {
58 return descriptorWithSign.GetFsVerityDescriptor().GetMerkleTreeOffset();
59 }
60
GetSignature()61 std::vector<int8_t>& ElfSignBlock::GetSignature()
62 {
63 return descriptorWithSign.GetSignature();
64 }
65
ToByteArray(std::vector<int8_t> & ret)66 void ElfSignBlock::ToByteArray(std::vector<int8_t>& ret)
67 {
68 std::unique_ptr<ByteBuffer> bf = std::make_unique<ByteBuffer>(Size());
69 bf->PutInt32(type);
70 bf->PutInt32(merkleTreeWithPadding.size());
71 bf->PutData(merkleTreeWithPadding.data(), merkleTreeWithPadding.size());
72 std::vector<int8_t> descriptorWithSignArr;
73 descriptorWithSign.ToByteArray(descriptorWithSignArr);
74 bf->PutData(descriptorWithSignArr.data(), descriptorWithSignArr.size());
75 ret = std::vector<int8_t>(bf->GetBufferPtr(), bf->GetBufferPtr() + bf->GetLimit());
76 }
77
FromByteArray(std::vector<int8_t> & bytes,ElfSignBlock & elfSignBlock)78 bool ElfSignBlock::FromByteArray(std::vector<int8_t>& bytes, ElfSignBlock& elfSignBlock)
79 {
80 std::unique_ptr<ByteBuffer> bf = std::make_unique<ByteBuffer>(bytes.size());
81 bf->PutData(bytes.data(), bytes.size());
82 bf->Flip();
83 int32_t inTreeType = 0;
84 bf->GetInt32(inTreeType);
85 if (MERKLE_TREE_INLINED != inTreeType) {
86 PrintErrorNumberMsg("VERIFY_ERROR", VERIFY_ERROR,
87 "The merkle tree type of elf signature block is incorrect");
88 return false;
89 }
90 int32_t inTreeLength = 0;
91 bf->GetInt32(inTreeLength);
92 std::vector<int8_t> treeWithPadding(inTreeLength);
93 bf->GetByte(treeWithPadding.data(), treeWithPadding.size());
94 int32_t inFsdType = 0;
95 bf->GetInt32(inFsdType);
96 if (FsVerityDescriptor::FS_VERITY_DESCRIPTOR_TYPE != inFsdType) {
97 PrintErrorNumberMsg("VERIFY_ERROR", VERIFY_ERROR,
98 "The FS descriptor type of elf signature block is incorrect");
99 return false;
100 }
101 int32_t inFsdLength = 0;
102 int tmpVariable = 2;
103 bf->GetInt32(inFsdLength);
104 if (bytes.size() != FsVerityDescriptorWithSign::INTEGER_BYTES * tmpVariable + inTreeLength +
105 FsVerityDescriptorWithSign::INTEGER_BYTES * tmpVariable + inFsdLength) {
106 PrintErrorNumberMsg("VERIFY_ERROR", VERIFY_ERROR,
107 "The signature length of the elf signature block is incorrect");
108 return false;
109 }
110 std::vector<int8_t> fsdArray(FsVerityDescriptor::DESCRIPTOR_SIZE);
111 bf->GetByte(fsdArray.data(), fsdArray.size());
112 FsVerityDescriptor fsd = FsVerityDescriptor::FromByteArray(fsdArray);
113 if (inFsdLength != fsd.GetSignSize() + FsVerityDescriptor::DESCRIPTOR_SIZE) {
114 PrintErrorNumberMsg("VERIFY_ERROR", VERIFY_ERROR,
115 "The signed size of the elf signature block is incorrect");
116 return false;
117 }
118 std::vector<int8_t> inSignature(inFsdLength - FsVerityDescriptor::DESCRIPTOR_SIZE);
119 bf->GetByte(inSignature.data(), inSignature.size());
120 FsVerityDescriptorWithSign fsVerityDescriptorWithSign(inFsdType, inFsdLength, fsd, inSignature);
121 elfSignBlock.type = inTreeType;
122 elfSignBlock.treeLength = inTreeLength;
123 elfSignBlock.merkleTreeWithPadding = treeWithPadding;
124 elfSignBlock.descriptorWithSign = fsVerityDescriptorWithSign;
125 return true;
126 }
127
ComputeMerkleTreePaddingLength(int64_t signBlockOffset)128 int32_t ElfSignBlock::ComputeMerkleTreePaddingLength(int64_t signBlockOffset)
129 {
130 int tmpVariable = 2;
131 return (int32_t)(PAGE_SIZE_4K - (signBlockOffset + FsVerityDescriptorWithSign::INTEGER_BYTES * tmpVariable)
132 % PAGE_SIZE_4K) % PAGE_SIZE_4K;
133 }
134
135 }
136 }