1 /* Distributed under the OSI-approved BSD 3-Clause License. See accompanying
2 file Copyright.txt or https://cmake.org/licensing for details. */
3 #include "cmUuid.h"
4
5 #include <array>
6 #include <cstring>
7
8 #include "cmCryptoHash.h"
9
10 static const std::array<int, 5> kUuidGroups = { { 4, 2, 2, 2, 6 } };
11
FromMd5(std::vector<unsigned char> const & uuidNamespace,std::string const & name) const12 std::string cmUuid::FromMd5(std::vector<unsigned char> const& uuidNamespace,
13 std::string const& name) const
14 {
15 std::vector<unsigned char> hashInput;
16 this->CreateHashInput(uuidNamespace, name, hashInput);
17
18 cmCryptoHash md5(cmCryptoHash::AlgoMD5);
19 md5.Initialize();
20 md5.Append(&hashInput[0], hashInput.size());
21 std::vector<unsigned char> digest = md5.Finalize();
22
23 return this->FromDigest(&digest[0], 3);
24 }
25
FromSha1(std::vector<unsigned char> const & uuidNamespace,std::string const & name) const26 std::string cmUuid::FromSha1(std::vector<unsigned char> const& uuidNamespace,
27 std::string const& name) const
28 {
29 std::vector<unsigned char> hashInput;
30 this->CreateHashInput(uuidNamespace, name, hashInput);
31
32 cmCryptoHash sha1(cmCryptoHash::AlgoSHA1);
33 sha1.Initialize();
34 sha1.Append(&hashInput[0], hashInput.size());
35 std::vector<unsigned char> digest = sha1.Finalize();
36
37 return this->FromDigest(&digest[0], 5);
38 }
39
CreateHashInput(std::vector<unsigned char> const & uuidNamespace,std::string const & name,std::vector<unsigned char> & output) const40 void cmUuid::CreateHashInput(std::vector<unsigned char> const& uuidNamespace,
41 std::string const& name,
42 std::vector<unsigned char>& output) const
43 {
44 output = uuidNamespace;
45
46 if (!name.empty()) {
47 output.resize(output.size() + name.size());
48
49 memcpy(&output[0] + uuidNamespace.size(), name.c_str(), name.size());
50 }
51 }
52
FromDigest(const unsigned char * digest,unsigned char version) const53 std::string cmUuid::FromDigest(const unsigned char* digest,
54 unsigned char version) const
55 {
56 using byte_t = unsigned char;
57
58 byte_t uuid[16] = { 0 };
59 memcpy(uuid, digest, 16);
60
61 uuid[6] &= 0xF;
62 uuid[6] |= byte_t(version << 4);
63
64 uuid[8] &= 0x3F;
65 uuid[8] |= 0x80;
66
67 return this->BinaryToString(uuid);
68 }
69
StringToBinary(std::string const & input,std::vector<unsigned char> & output) const70 bool cmUuid::StringToBinary(std::string const& input,
71 std::vector<unsigned char>& output) const
72 {
73 output.clear();
74 output.reserve(16);
75
76 if (input.length() != 36) {
77 return false;
78 }
79 size_t index = 0;
80 for (size_t i = 0; i < kUuidGroups.size(); ++i) {
81 if (i != 0 && input[index++] != '-') {
82 return false;
83 }
84 size_t digits = kUuidGroups[i] * 2;
85 if (!this->StringToBinaryImpl(input.substr(index, digits), output)) {
86 return false;
87 }
88
89 index += digits;
90 }
91
92 return true;
93 }
94
BinaryToString(const unsigned char * input) const95 std::string cmUuid::BinaryToString(const unsigned char* input) const
96 {
97 std::string output;
98
99 size_t inputIndex = 0;
100 for (size_t i = 0; i < kUuidGroups.size(); ++i) {
101 if (i != 0) {
102 output += '-';
103 }
104
105 size_t bytes = kUuidGroups[i];
106 for (size_t j = 0; j < bytes; ++j) {
107 unsigned char byte = input[inputIndex++];
108 output += this->ByteToHex(byte);
109 }
110 }
111
112 return output;
113 }
114
ByteToHex(unsigned char byte) const115 std::string cmUuid::ByteToHex(unsigned char byte) const
116 {
117 std::string result(" ");
118 for (int i = 0; i < 2; ++i) {
119 unsigned char rest = byte % 16;
120 byte /= 16;
121 char c = (rest < 0xA) ? char('0' + rest) : char('a' + (rest - 0xA));
122 result.at(1 - i) = c;
123 }
124
125 return result;
126 }
127
StringToBinaryImpl(std::string const & input,std::vector<unsigned char> & output) const128 bool cmUuid::StringToBinaryImpl(std::string const& input,
129 std::vector<unsigned char>& output) const
130 {
131 if (input.size() % 2) {
132 return false;
133 }
134
135 for (size_t i = 0; i < input.size(); i += 2) {
136 char c1 = 0;
137 if (!this->IntFromHexDigit(input[i], c1)) {
138 return false;
139 }
140
141 char c2 = 0;
142 if (!this->IntFromHexDigit(input[i + 1], c2)) {
143 return false;
144 }
145
146 output.push_back(char(c1 << 4 | c2));
147 }
148
149 return true;
150 }
151
IntFromHexDigit(char input,char & output) const152 bool cmUuid::IntFromHexDigit(char input, char& output) const
153 {
154 if (input >= '0' && input <= '9') {
155 output = char(input - '0');
156 return true;
157 }
158 if (input >= 'a' && input <= 'f') {
159 output = char(input - 'a' + 0xA);
160 return true;
161 }
162 if (input >= 'A' && input <= 'F') {
163 output = char(input - 'A' + 0xA);
164 return true;
165 }
166 return false;
167 }
168