1 /*
2 This file is part of the Okteta Kasten module, made within the KDE community.
3
4 SPDX-FileCopyrightText: 2010 Friedrich W. H. Kossebau <kossebau@kde.org>
5
6 SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
7 */
8
9 #include "bytearraybase32streamencoder.hpp"
10
11 // Okteta core
12 #include <Okteta/AbstractByteArrayModel>
13 // KF
14 #include <KLocalizedString>
15 // Qt
16 #include <QTextStream>
17
18 namespace Kasten {
19
20 static constexpr char base32ClassicEncodeMap[32] =
21 {
22 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
23 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
24 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
25 'Y', 'Z', '2', '3', '4', '5', '6', '7'
26 };
27 static constexpr char base32HexEncodeMap[32] =
28 {
29 '0', '1', '2', '3', '4', '5', '6', '7',
30 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F',
31 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N',
32 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V'
33 };
34 static constexpr char base32ZHexEncodeMap[32] =
35 {
36 'y', 'b', 'n', 'd', 'r', 'f', 'g', '8',
37 'e', 'j', 'k', 'm', 'c', 'p', 'q', 'x',
38 'o', 't', '1', 'u', 'w', 'i', 's', 'z',
39 'a', '3', '4', '5', 'h', '7', '6', '9'
40 };
41
42 static constexpr const char* base32PaddingData[4] =
43 {
44 "======",
45 "====",
46 "===",
47 "="
48 };
49
base32Padding(ByteArrayBase32StreamEncoder::InputByteIndex index)50 static inline constexpr const char* base32Padding(ByteArrayBase32StreamEncoder::InputByteIndex index)
51 {
52 return base32PaddingData[static_cast<int>(index) - 1];
53 }
noPadding(ByteArrayBase32StreamEncoder::InputByteIndex)54 static inline constexpr const char* noPadding(ByteArrayBase32StreamEncoder::InputByteIndex /*index*/)
55 {
56 return "";
57 }
58
59 struct Base32EncodingData
60 {
61 const char* const encodeMap;
62 const char* (* padding)(ByteArrayBase32StreamEncoder::InputByteIndex);
63 };
64
65 static constexpr Base32EncodingData
66 base32EncodingData[3] =
67 {
68 {base32ClassicEncodeMap, &base32Padding},
69 {base32HexEncodeMap, &base32Padding},
70 {base32ZHexEncodeMap, &noPadding}
71 };
72
73 Base32StreamEncoderSettings::Base32StreamEncoderSettings() = default;
74
ByteArrayBase32StreamEncoder()75 ByteArrayBase32StreamEncoder::ByteArrayBase32StreamEncoder()
76 : AbstractByteArrayStreamEncoder(i18nc("name of the encoding target", "Base32"), QStringLiteral("text/x-base32"))
77 {}
78
79 ByteArrayBase32StreamEncoder::~ByteArrayBase32StreamEncoder() = default;
80
encodeDataToStream(QIODevice * device,const ByteArrayView * byteArrayView,const Okteta::AbstractByteArrayModel * byteArrayModel,const Okteta::AddressRange & range)81 bool ByteArrayBase32StreamEncoder::encodeDataToStream(QIODevice* device,
82 const ByteArrayView* byteArrayView,
83 const Okteta::AbstractByteArrayModel* byteArrayModel,
84 const Okteta::AddressRange& range)
85 {
86 Q_UNUSED(byteArrayView);
87
88 bool success = true;
89
90 // encode
91 QTextStream textStream(device);
92
93 // prepare
94 const auto& algorithmEncodingData = base32EncodingData[static_cast<int>(mSettings.algorithmId)];
95 const char* const base32EncodeMap = algorithmEncodingData.encodeMap;
96 const char* (* base32Padding)(InputByteIndex) = algorithmEncodingData.padding;
97
98 InputByteIndex inputByteIndex = InputByteIndex::First;
99 int outputGroupsPerLine = 0;
100 unsigned char bitsFromLastByte;
101
102 for (Okteta::Address i = range.start(); i <= range.end(); ++i) {
103 const Okteta::Byte byte = byteArrayModel->byte(i);
104
105 switch (inputByteIndex)
106 {
107 case InputByteIndex::First:
108 // bits 7..3
109 textStream << base32EncodeMap[(byte >> 3)];
110 // bits 2..0 -> 4..2 for next
111 bitsFromLastByte = (byte & 0x7) << 2;
112 inputByteIndex = InputByteIndex::Second;
113 break;
114 case InputByteIndex::Second:
115 // from last and bits 7..6 as 1..0 from this
116 textStream << base32EncodeMap[(bitsFromLastByte | byte >> 6)];
117 // bits 5..1 as 4..0
118 textStream << base32EncodeMap[(byte & 0x3E) >> 1];
119 // bits 0 -> 4 for next
120 bitsFromLastByte = (byte & 0x1) << 4;
121 inputByteIndex = InputByteIndex::Third;
122 break;
123 case InputByteIndex::Third:
124 // from last and bits 7..4 as 3..0 from this
125 textStream << base32EncodeMap[(bitsFromLastByte | byte >> 4)];
126 // bits 3..0 -> 4..1 for next
127 bitsFromLastByte = (byte & 0xF) << 1;
128 inputByteIndex = InputByteIndex::Fourth;
129 break;
130 case InputByteIndex::Fourth:
131 // from last and bit 7 as 0 from this
132 textStream << base32EncodeMap[(bitsFromLastByte | byte >> 7)];
133 // bits 6..2 as 4..0
134 textStream << base32EncodeMap[(byte & 0x7C) >> 2];
135 // bits 1..0 -> 4..3 for next
136 bitsFromLastByte = (byte & 0x3) << 3;
137 inputByteIndex = InputByteIndex::Fifth;
138 break;
139 case InputByteIndex::Fifth:
140 // from last and bits 7..5 as 2..0 from this
141 textStream << base32EncodeMap[(bitsFromLastByte | byte >> 5)];
142 // bits 4..0
143 textStream << base32EncodeMap[(byte & 0x1F)];
144 inputByteIndex = InputByteIndex::First;
145 ++outputGroupsPerLine;
146 if (outputGroupsPerLine >= maxOutputGroupsPerLine && i < range.end()) {
147 textStream << "\r\n";
148 outputGroupsPerLine = 0;
149 }
150 break;
151 }
152 }
153
154 const bool hasBitsLeft = (inputByteIndex != InputByteIndex::First);
155 if (hasBitsLeft) {
156 textStream << base32EncodeMap[bitsFromLastByte]
157 << base32Padding(inputByteIndex);
158 }
159
160 return success;
161 }
162
163 }
164