1/* 2 * Copyright (C) 2010, 2011 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' 14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS 17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 23 * THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#include "config.h" 27#include "ArgumentDecoder.h" 28 29#include "DataReference.h" 30#include <stdio.h> 31 32namespace IPC { 33 34ArgumentDecoder::ArgumentDecoder(const uint8_t* buffer, size_t bufferSize) 35{ 36 initialize(buffer, bufferSize); 37} 38 39ArgumentDecoder::ArgumentDecoder(const uint8_t* buffer, size_t bufferSize, Vector<Attachment> attachments) 40{ 41 initialize(buffer, bufferSize); 42 43 m_attachments = WTF::move(attachments); 44} 45 46ArgumentDecoder::~ArgumentDecoder() 47{ 48 ASSERT(m_buffer); 49 free(m_buffer); 50#if !USE(UNIX_DOMAIN_SOCKETS) 51 // FIXME: We need to dispose of the mach ports in cases of failure. 52#else 53 Vector<Attachment>::iterator end = m_attachments.end(); 54 for (Vector<Attachment>::iterator it = m_attachments.begin(); it != end; ++it) 55 it->dispose(); 56#endif 57} 58 59static inline uint8_t* roundUpToAlignment(uint8_t* ptr, unsigned alignment) 60{ 61 // Assert that the alignment is a power of 2. 62 ASSERT(alignment && !(alignment & (alignment - 1))); 63 64 uintptr_t alignmentMask = alignment - 1; 65 return reinterpret_cast<uint8_t*>((reinterpret_cast<uintptr_t>(ptr) + alignmentMask) & ~alignmentMask); 66} 67 68void ArgumentDecoder::initialize(const uint8_t* buffer, size_t bufferSize) 69{ 70 m_buffer = static_cast<uint8_t*>(malloc(bufferSize)); 71 72 ASSERT(!(reinterpret_cast<uintptr_t>(m_buffer) % alignof(uint64_t))); 73 74 m_bufferPos = m_buffer; 75 m_bufferEnd = m_buffer + bufferSize; 76 memcpy(m_buffer, buffer, bufferSize); 77} 78 79static inline bool alignedBufferIsLargeEnoughToContain(const uint8_t* alignedPosition, const uint8_t* bufferEnd, size_t size) 80{ 81 return bufferEnd >= alignedPosition && static_cast<size_t>(bufferEnd - alignedPosition) >= size; 82} 83 84bool ArgumentDecoder::alignBufferPosition(unsigned alignment, size_t size) 85{ 86 uint8_t* alignedPosition = roundUpToAlignment(m_bufferPos, alignment); 87 if (!alignedBufferIsLargeEnoughToContain(alignedPosition, m_bufferEnd, size)) { 88 // We've walked off the end of this buffer. 89 markInvalid(); 90 return false; 91 } 92 93 m_bufferPos = alignedPosition; 94 return true; 95} 96 97bool ArgumentDecoder::bufferIsLargeEnoughToContain(unsigned alignment, size_t size) const 98{ 99 return alignedBufferIsLargeEnoughToContain(roundUpToAlignment(m_bufferPos, alignment), m_bufferEnd, size); 100} 101 102bool ArgumentDecoder::decodeFixedLengthData(uint8_t* data, size_t size, unsigned alignment) 103{ 104 if (!alignBufferPosition(alignment, size)) 105 return false; 106 107 memcpy(data, m_bufferPos, size); 108 m_bufferPos += size; 109 110 return true; 111} 112 113bool ArgumentDecoder::decodeVariableLengthByteArray(DataReference& dataReference) 114{ 115 uint64_t size; 116 if (!decode(size)) 117 return false; 118 119 if (!alignBufferPosition(1, size)) 120 return false; 121 122 uint8_t* data = m_bufferPos; 123 m_bufferPos += size; 124 125 dataReference = DataReference(data, size); 126 return true; 127} 128 129template<typename Type> 130static void decodeValueFromBuffer(Type& value, uint8_t*& bufferPosition) 131{ 132 memcpy(&value, bufferPosition, sizeof(value)); 133 bufferPosition += sizeof(Type); 134} 135 136bool ArgumentDecoder::decode(bool& result) 137{ 138 if (!alignBufferPosition(sizeof(result), sizeof(result))) 139 return false; 140 141 decodeValueFromBuffer(result, m_bufferPos); 142 return true; 143} 144 145bool ArgumentDecoder::decode(uint8_t& result) 146{ 147 if (!alignBufferPosition(sizeof(result), sizeof(result))) 148 return false; 149 150 decodeValueFromBuffer(result, m_bufferPos); 151 return true; 152} 153 154bool ArgumentDecoder::decode(uint16_t& result) 155{ 156 if (!alignBufferPosition(sizeof(result), sizeof(result))) 157 return false; 158 159 decodeValueFromBuffer(result, m_bufferPos); 160 return true; 161} 162 163bool ArgumentDecoder::decode(uint32_t& result) 164{ 165 if (!alignBufferPosition(sizeof(result), sizeof(result))) 166 return false; 167 168 decodeValueFromBuffer(result, m_bufferPos); 169 return true; 170} 171 172bool ArgumentDecoder::decode(uint64_t& result) 173{ 174 if (!alignBufferPosition(sizeof(result), sizeof(result))) 175 return false; 176 177 decodeValueFromBuffer(result, m_bufferPos); 178 return true; 179} 180 181bool ArgumentDecoder::decode(int32_t& result) 182{ 183 if (!alignBufferPosition(sizeof(result), sizeof(result))) 184 return false; 185 186 decodeValueFromBuffer(result, m_bufferPos); 187 return true; 188} 189 190bool ArgumentDecoder::decode(int64_t& result) 191{ 192 if (!alignBufferPosition(sizeof(result), sizeof(result))) 193 return false; 194 195 decodeValueFromBuffer(result, m_bufferPos); 196 return true; 197} 198 199bool ArgumentDecoder::decode(float& result) 200{ 201 if (!alignBufferPosition(sizeof(result), sizeof(result))) 202 return false; 203 204 decodeValueFromBuffer(result, m_bufferPos); 205 return true; 206} 207 208bool ArgumentDecoder::decode(double& result) 209{ 210 if (!alignBufferPosition(sizeof(result), sizeof(result))) 211 return false; 212 213 decodeValueFromBuffer(result, m_bufferPos); 214 return true; 215} 216 217bool ArgumentDecoder::removeAttachment(Attachment& attachment) 218{ 219 if (m_attachments.isEmpty()) 220 return false; 221 222 attachment = m_attachments.last(); 223 m_attachments.removeLast(); 224 return true; 225} 226 227} // namespace IPC 228