1/* 2 Copyright (C) 2000-2001 Dawit Alemayehu <adawit@kde.org> 3 Copyright (C) 2006 Alexey Proskuryakov <ap@webkit.org> 4 Copyright (C) 2007, 2008, 2013 Apple Inc. All rights reserved. 5 Copyright (C) 2010 Patrick Gansterer <paroga@paroga.com> 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU Lesser General Public License (LGPL) 9 version 2 as published by the Free Software Foundation. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU Library General Public 17 License along with this program; if not, write to the Free Software 18 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 19 20 This code is based on the java implementation in HTTPClient 21 package by Ronald Tschalär Copyright (C) 1996-1999. 22*/ 23 24#include "config.h" 25#include "Base64.h" 26 27#include <limits.h> 28#include <wtf/StringExtras.h> 29#include <wtf/text/WTFString.h> 30 31namespace WTF { 32 33const char nonAlphabet = -1; 34 35static const char base64EncMap[64] = { 36 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 37 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50, 38 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 39 0x59, 0x5A, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 40 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 41 0x6F, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 42 0x77, 0x78, 0x79, 0x7A, 0x30, 0x31, 0x32, 0x33, 43 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x2B, 0x2F 44}; 45 46static const char base64DecMap[128] = { 47 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 48 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 49 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 50 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 51 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 52 nonAlphabet, nonAlphabet, nonAlphabet, 0x3E, nonAlphabet, nonAlphabet, nonAlphabet, 0x3F, 53 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 54 0x3C, 0x3D, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 55 nonAlphabet, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 56 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 57 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 58 0x17, 0x18, 0x19, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 59 nonAlphabet, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 60 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 61 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30, 62 0x31, 0x32, 0x33, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet 63}; 64 65static const char base64URLEncMap[64] = { 66 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 67 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50, 68 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 69 0x59, 0x5A, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 70 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 71 0x6F, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 72 0x77, 0x78, 0x79, 0x7A, 0x30, 0x31, 0x32, 0x33, 73 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x2D, 0x5F 74}; 75 76static const char base64URLDecMap[128] = { 77 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 78 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 79 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 80 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 81 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 82 nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 0x3E, nonAlphabet, nonAlphabet, 83 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 84 0x3C, 0x3D, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 85 nonAlphabet, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 86 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 87 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 88 0x17, 0x18, 0x19, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, 0x3F, 89 nonAlphabet, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 90 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 91 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30, 92 0x31, 0x32, 0x33, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet, nonAlphabet 93}; 94 95static inline void base64EncodeInternal(const char* data, unsigned len, Vector<char>& out, Base64EncodePolicy policy, const char (&encodeMap)[64]) 96{ 97 out.clear(); 98 if (!len) 99 return; 100 101 // If the input string is pathologically large, just return nothing. 102 // Note: Keep this in sync with the "outLength" computation below. 103 // Rather than being perfectly precise, this is a bit conservative. 104 const unsigned maxInputBufferSize = UINT_MAX / 77 * 76 / 4 * 3 - 2; 105 if (len > maxInputBufferSize) 106 return; 107 108 unsigned sidx = 0; 109 unsigned didx = 0; 110 111 unsigned outLength = ((len + 2) / 3) * 4; 112 113 // Deal with the 76 character per line limit specified in RFC 2045. 114 bool insertLFs = (policy == Base64InsertLFs && outLength > 76); 115 if (insertLFs) 116 outLength += ((outLength - 1) / 76); 117 118 int count = 0; 119 out.grow(outLength); 120 121 // 3-byte to 4-byte conversion + 0-63 to ascii printable conversion 122 if (len > 1) { 123 while (sidx < len - 2) { 124 if (insertLFs) { 125 if (count && !(count % 76)) 126 out[didx++] = '\n'; 127 count += 4; 128 } 129 out[didx++] = encodeMap[(data[sidx] >> 2) & 077]; 130 out[didx++] = encodeMap[((data[sidx + 1] >> 4) & 017) | ((data[sidx] << 4) & 077)]; 131 out[didx++] = encodeMap[((data[sidx + 2] >> 6) & 003) | ((data[sidx + 1] << 2) & 077)]; 132 out[didx++] = encodeMap[data[sidx + 2] & 077]; 133 sidx += 3; 134 } 135 } 136 137 if (sidx < len) { 138 if (insertLFs && (count > 0) && !(count % 76)) 139 out[didx++] = '\n'; 140 141 out[didx++] = encodeMap[(data[sidx] >> 2) & 077]; 142 if (sidx < len - 1) { 143 out[didx++] = encodeMap[((data[sidx + 1] >> 4) & 017) | ((data[sidx] << 4) & 077)]; 144 out[didx++] = encodeMap[(data[sidx + 1] << 2) & 077]; 145 } else 146 out[didx++] = encodeMap[(data[sidx] << 4) & 077]; 147 } 148 149 // Add padding 150 if (policy == Base64URLPolicy) 151 out.resize(didx); 152 else { 153 while (didx < out.size()) { 154 out[didx] = '='; 155 ++didx; 156 } 157 } 158} 159 160String base64Encode(const void* data, unsigned length, Base64EncodePolicy policy) 161{ 162 Vector<char> result; 163 base64EncodeInternal(static_cast<const char*>(data), length, result, policy, base64EncMap); 164 return String(result.data(), result.size()); 165} 166 167void base64Encode(const void* data, unsigned len, Vector<char>& out, Base64EncodePolicy policy) 168{ 169 base64EncodeInternal(static_cast<const char*>(data), len, out, policy, base64EncMap); 170} 171 172String base64URLEncode(const void* data, unsigned length) 173{ 174 Vector<char> result; 175 base64EncodeInternal(static_cast<const char*>(data), length, result, Base64URLPolicy, base64URLEncMap); 176 return String(result.data(), result.size()); 177} 178 179void base64URLEncode(const void* data, unsigned len, Vector<char>& out) 180{ 181 base64EncodeInternal(static_cast<const char*>(data), len, out, Base64URLPolicy, base64URLEncMap); 182} 183 184template<typename T> 185static inline bool base64DecodeInternal(const T* data, unsigned length, Vector<char>& out, Base64DecodePolicy policy, const char (&decodeMap)[128]) 186{ 187 out.clear(); 188 if (!length) 189 return true; 190 191 out.grow(length); 192 193 unsigned equalsSignCount = 0; 194 unsigned outLength = 0; 195 for (unsigned idx = 0; idx < length; ++idx) { 196 unsigned ch = data[idx]; 197 if (ch == '=') { 198 ++equalsSignCount; 199 // There should be no padding if length is a multiple of 4, and there 200 // should never be more than 2 padding characters. 201 if (policy == Base64FailOnInvalidCharacterOrExcessPadding && (length % 4 || equalsSignCount > 2)) 202 return false; 203 } else { 204 char decodedCharacter = ch < WTF_ARRAY_LENGTH(decodeMap) ? decodeMap[ch] : nonAlphabet; 205 if (decodedCharacter != nonAlphabet) { 206 if (equalsSignCount) 207 return false; 208 out[outLength] = decodedCharacter; 209 ++outLength; 210 } else if (policy == Base64FailOnInvalidCharacterOrExcessPadding || policy == Base64FailOnInvalidCharacter || (policy == Base64IgnoreWhitespace && !isSpaceOrNewline(ch))) 211 return false; 212 } 213 } 214 215 if (!outLength) 216 return !equalsSignCount; 217 218 // Valid data is (n * 4 + [0,2,3]) characters long. 219 if ((outLength % 4) == 1) 220 return false; 221 222 // 4-byte to 3-byte conversion 223 outLength -= (outLength + 3) / 4; 224 if (!outLength) 225 return false; 226 227 unsigned sidx = 0; 228 unsigned didx = 0; 229 if (outLength > 1) { 230 while (didx < outLength - 2) { 231 out[didx] = (((out[sidx] << 2) & 255) | ((out[sidx + 1] >> 4) & 003)); 232 out[didx + 1] = (((out[sidx + 1] << 4) & 255) | ((out[sidx + 2] >> 2) & 017)); 233 out[didx + 2] = (((out[sidx + 2] << 6) & 255) | (out[sidx + 3] & 077)); 234 sidx += 4; 235 didx += 3; 236 } 237 } 238 239 if (didx < outLength) 240 out[didx] = (((out[sidx] << 2) & 255) | ((out[sidx + 1] >> 4) & 003)); 241 242 if (++didx < outLength) 243 out[didx] = (((out[sidx + 1] << 4) & 255) | ((out[sidx + 2] >> 2) & 017)); 244 245 if (outLength < out.size()) 246 out.shrink(outLength); 247 248 return true; 249} 250 251bool base64Decode(const String& in, SignedOrUnsignedCharVectorAdapter out, Base64DecodePolicy policy) 252{ 253 unsigned length = in.length(); 254 if (!length || in.is8Bit()) 255 return base64DecodeInternal(in.characters8(), length, out, policy, base64DecMap); 256 return base64DecodeInternal(in.characters16(), length, out, policy, base64DecMap); 257} 258 259bool base64Decode(const Vector<char>& in, SignedOrUnsignedCharVectorAdapter out, Base64DecodePolicy policy) 260{ 261 out.clear(); 262 263 // If the input string is pathologically large, just return nothing. 264 if (in.size() > UINT_MAX) 265 return false; 266 267 return base64DecodeInternal(reinterpret_cast<const LChar*>(in.data()), in.size(), out, policy, base64DecMap); 268} 269 270bool base64Decode(const char* data, unsigned len, SignedOrUnsignedCharVectorAdapter out, Base64DecodePolicy policy) 271{ 272 return base64DecodeInternal(reinterpret_cast<const LChar*>(data), len, out, policy, base64DecMap); 273} 274 275bool base64URLDecode(const String& in, SignedOrUnsignedCharVectorAdapter out) 276{ 277 unsigned length = in.length(); 278 if (!length || in.is8Bit()) 279 return base64DecodeInternal(in.characters8(), length, out, Base64FailOnInvalidCharacter, base64URLDecMap); 280 return base64DecodeInternal(in.characters16(), length, out, Base64FailOnInvalidCharacter, base64URLDecMap); 281} 282 283bool base64URLDecode(const Vector<char>& in, SignedOrUnsignedCharVectorAdapter out) 284{ 285 out.clear(); 286 287 // If the input string is pathologically large, just return nothing. 288 if (in.size() > UINT_MAX) 289 return false; 290 291 return base64DecodeInternal(reinterpret_cast<const LChar*>(in.data()), in.size(), out, Base64FailOnInvalidCharacter, base64URLDecMap); 292} 293 294bool base64URLDecode(const char* data, unsigned len, SignedOrUnsignedCharVectorAdapter out) 295{ 296 return base64DecodeInternal(reinterpret_cast<const LChar*>(data), len, out, Base64FailOnInvalidCharacter, base64URLDecMap); 297} 298 299} // namespace WTF 300