1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 /*
3 * This file is part of the LibreOffice project.
4 *
5 * This Source Code Form is subject to the terms of the Mozilla Public
6 * License, v. 2.0. If a copy of the MPL was not distributed with this
7 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
8 *
9 * This file incorporates work covered by the following license notice:
10 *
11 * Licensed to the Apache Software Foundation (ASF) under one or more
12 * contributor license agreements. See the NOTICE file distributed
13 * with this work for additional information regarding copyright
14 * ownership. The ASF licenses this file to you under the Apache
15 * License, Version 2.0 (the "License"); you may not use this file
16 * except in compliance with the License. You may obtain a copy of
17 * the License at http://www.apache.org/licenses/LICENSE-2.0 .
18 */
19
20 #include <comphelper/base64.hxx>
21
22 #include <com/sun/star/uno/Sequence.hxx>
23
24 #include <osl/diagnose.h>
25
26 using namespace com::sun::star;
27
28 namespace comphelper {
29
30 const
31 char aBase64EncodeTable[] =
32 { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
33 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
34 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
35 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
36 '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/' };
37
38 const
39 sal_uInt8 aBase64DecodeTable[] =
40 { 62,255,255,255, 63, // 43-47
41 // + /
42
43 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,255,255,255, 0,255,255, // 48-63
44 // 0 1 2 3 4 5 6 7 8 9 =
45
46 255, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, // 64-79
47 // A B C D E F G H I J K L M N O
48
49 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,255,255,255,255,255, // 80-95
50 // P Q R S T U V W X Y Z
51
52 0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, // 96-111
53 // a b c d e f g h i j k l m n o
54
55 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 }; // 112-123
56 // p q r s t u v w x y z
57
58
ThreeByteToFourByte(const sal_Int8 * pBuffer,const sal_Int32 nStart,const sal_Int32 nFullLen,char * aCharBuffer)59 static void ThreeByteToFourByte(const sal_Int8* pBuffer, const sal_Int32 nStart, const sal_Int32 nFullLen, char* aCharBuffer)
60 {
61 sal_Int32 nLen(nFullLen - nStart);
62 if (nLen > 3)
63 nLen = 3;
64 if (nLen == 0)
65 {
66 return;
67 }
68
69 sal_Int32 nBinaer;
70 switch (nLen)
71 {
72 case 1:
73 {
74 nBinaer = static_cast<sal_uInt8>(pBuffer[nStart + 0]) << 16;
75 }
76 break;
77 case 2:
78 {
79 nBinaer = (static_cast<sal_uInt8>(pBuffer[nStart + 0]) << 16) +
80 (static_cast<sal_uInt8>(pBuffer[nStart + 1]) << 8);
81 }
82 break;
83 default:
84 {
85 nBinaer = (static_cast<sal_uInt8>(pBuffer[nStart + 0]) << 16) +
86 (static_cast<sal_uInt8>(pBuffer[nStart + 1]) << 8) +
87 static_cast<sal_uInt8>(pBuffer[nStart + 2]);
88 }
89 break;
90 }
91
92 aCharBuffer[0] = aCharBuffer[1] = aCharBuffer[2] = aCharBuffer[3] = '=';
93
94 sal_uInt8 nIndex (static_cast<sal_uInt8>((nBinaer & 0xFC0000) >> 18));
95 aCharBuffer[0] = aBase64EncodeTable [nIndex];
96
97 nIndex = static_cast<sal_uInt8>((nBinaer & 0x3F000) >> 12);
98 aCharBuffer[1] = aBase64EncodeTable [nIndex];
99 if (nLen > 1)
100 {
101 nIndex = static_cast<sal_uInt8>((nBinaer & 0xFC0) >> 6);
102 aCharBuffer[2] = aBase64EncodeTable [nIndex];
103 if (nLen > 2)
104 {
105 nIndex = static_cast<sal_uInt8>((nBinaer & 0x3F));
106 aCharBuffer[3] = aBase64EncodeTable [nIndex];
107 }
108 }
109 }
110
encode(OStringBuffer & aStrBuffer,const uno::Sequence<sal_Int8> & aPass)111 void Base64::encode(OStringBuffer& aStrBuffer, const uno::Sequence<sal_Int8>& aPass)
112 {
113 sal_Int32 i(0);
114 sal_Int32 nBufferLength(aPass.getLength());
115 const sal_Int8* pBuffer = aPass.getConstArray();
116 while (i < nBufferLength)
117 {
118 char aCharBuffer[4];
119 ThreeByteToFourByte(pBuffer, i, nBufferLength, aCharBuffer);
120 aStrBuffer.append(aCharBuffer, SAL_N_ELEMENTS(aCharBuffer));
121 i += 3;
122 }
123 }
124
encode(OUStringBuffer & aStrBuffer,const uno::Sequence<sal_Int8> & aPass)125 void Base64::encode(OUStringBuffer& aStrBuffer, const uno::Sequence<sal_Int8>& aPass)
126 {
127 sal_Int32 i(0);
128 sal_Int32 nBufferLength(aPass.getLength());
129 const sal_Int8* pBuffer = aPass.getConstArray();
130 while (i < nBufferLength)
131 {
132 char aCharBuffer[4];
133 ThreeByteToFourByte(pBuffer, i, nBufferLength, aCharBuffer);
134 aStrBuffer.appendAscii(aCharBuffer, SAL_N_ELEMENTS(aCharBuffer));
135 i += 3;
136 }
137 }
138
decode(uno::Sequence<sal_Int8> & aBuffer,const OUString & sBuffer)139 void Base64::decode(uno::Sequence<sal_Int8>& aBuffer, const OUString& sBuffer)
140 {
141 sal_Int32 nCharsDecoded = decodeSomeChars( aBuffer, sBuffer );
142 OSL_ENSURE( nCharsDecoded == sBuffer.getLength(), "some bytes left in base64 decoding!" );
143 }
144
decodeSomeChars(uno::Sequence<sal_Int8> & rOutBuffer,const OUString & rInBuffer)145 sal_Int32 Base64::decodeSomeChars(uno::Sequence<sal_Int8>& rOutBuffer, const OUString& rInBuffer)
146 {
147 sal_Int32 nInBufferLen = rInBuffer.getLength();
148 sal_Int32 nMinOutBufferLen = (nInBufferLen / 4) * 3;
149 if( rOutBuffer.getLength() < nMinOutBufferLen )
150 rOutBuffer.realloc( nMinOutBufferLen );
151
152 const sal_Unicode *pInBuffer = rInBuffer.getStr();
153 sal_Int8 *pOutBuffer = rOutBuffer.getArray();
154 sal_Int8 *pOutBufferStart = pOutBuffer;
155 sal_Int32 nCharsDecoded = 0;
156
157 sal_uInt8 aDecodeBuffer[4];
158 sal_Int32 nBytesToDecode = 0;
159 sal_Int32 nBytesGotFromDecoding = 3;
160 sal_Int32 nInBufferPos= 0;
161 while( nInBufferPos < nInBufferLen )
162 {
163 sal_Unicode cChar = *pInBuffer;
164 if( cChar >= '+' && cChar <= 'z' )
165 {
166 sal_uInt8 nByte = aBase64DecodeTable[cChar-'+'];
167 if( nByte != 255 )
168 {
169 // We have found a valid character!
170 aDecodeBuffer[nBytesToDecode++] = nByte;
171
172 // One '=' character at the end means 2 out bytes
173 // Two '=' characters at the end mean 1 out bytes
174 if( '=' == cChar && nBytesToDecode > 2 )
175 nBytesGotFromDecoding--;
176 if( 4 == nBytesToDecode )
177 {
178 // Four characters found, so we may convert now!
179 sal_uInt32 nOut = (aDecodeBuffer[0] << 18) +
180 (aDecodeBuffer[1] << 12) +
181 (aDecodeBuffer[2] << 6) +
182 aDecodeBuffer[3];
183
184 *pOutBuffer++ = static_cast<sal_Int8>((nOut & 0xff0000) >> 16);
185 if( nBytesGotFromDecoding > 1 )
186 *pOutBuffer++ = static_cast<sal_Int8>((nOut & 0xff00) >> 8);
187 if( nBytesGotFromDecoding > 2 )
188 *pOutBuffer++ = static_cast<sal_Int8>(nOut & 0xff);
189 nCharsDecoded = nInBufferPos + 1;
190 nBytesToDecode = 0;
191 nBytesGotFromDecoding = 3;
192 }
193 }
194 else
195 {
196 nCharsDecoded++;
197 }
198 }
199 else
200 {
201 nCharsDecoded++;
202 }
203
204 nInBufferPos++;
205 pInBuffer++;
206 }
207 if( (pOutBuffer - pOutBufferStart) != rOutBuffer.getLength() )
208 rOutBuffer.realloc( pOutBuffer - pOutBufferStart );
209
210 return nCharsDecoded;
211 }
212
213 }
214
215 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
216