kicad/thirdparty/compoundfilereader/compoundfilereader.h

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/**
Microsoft Compound File (and Property Set) Reader
http://en.wikipedia.org/wiki/Compound_File_Binary_Format
Format specification:
MS-CFB: https://msdn.microsoft.com/en-us/library/dd942138.aspx
MS-OLEPS: https://msdn.microsoft.com/en-us/library/dd942421.aspx
Note:
1. For simplification, the code assumes that the target system is little-endian.
2. The reader operates the passed buffer in-place.
You must keep the input buffer valid when you are using the reader.
3. Single thread usage.
Example 1: print all streams in a compound file
\code
CFB::CompoundFileReader reader(buffer, len);
reader.EnumFiles(reader.GetRootEntry(), -1,
[&](const CFB::COMPOUND_FILE_ENTRY* entry, const CFB::utf16string& dir, int level)->void
{
bool isDirectory = !reader.IsStream(entry);
std::string name = UTF16ToUTF8(entry->name);
std::string indentstr(level * 4, ' ');
printf("%s%s%s%s\n", indentstr.c_str(), isDirectory ? "[" : "", name.c_str(), isDirectory ? "]" : "");
});
\endcode
*/
#include <algorithm>
#include <stdint.h>
#include <string.h>
#include <exception>
#include <stdexcept>
#include <functional>
namespace CFB
{
struct CFBException : public std::runtime_error
{
CFBException(const char* desc) : std::runtime_error(desc) {}
};
struct WrongFormat : public CFBException
{
WrongFormat() : CFBException("Wrong file format") {}
};
struct FileCorrupted : public CFBException
{
FileCorrupted() : CFBException("File corrupted") {}
};
#pragma pack(push)
#pragma pack(1)
struct COMPOUND_FILE_HDR
{
unsigned char signature[8];
unsigned char unused_clsid[16];
uint16_t minorVersion;
uint16_t majorVersion;
uint16_t byteOrder;
uint16_t sectorShift;
uint16_t miniSectorShift;
unsigned char reserved[6];
uint32_t numDirectorySector;
uint32_t numFATSector;
uint32_t firstDirectorySectorLocation;
uint32_t transactionSignatureNumber;
uint32_t miniStreamCutoffSize;
uint32_t firstMiniFATSectorLocation;
uint32_t numMiniFATSector;
uint32_t firstDIFATSectorLocation;
uint32_t numDIFATSector;
uint32_t headerDIFAT[109];
};
struct COMPOUND_FILE_ENTRY
{
uint16_t name[32];
uint16_t nameLen;
uint8_t type;
uint8_t colorFlag;
uint32_t leftSiblingID; // Note that it's actually the left/right child in the RB-tree.
uint32_t rightSiblingID; // So entry.leftSibling.rightSibling does NOT go back to entry.
uint32_t childID;
unsigned char clsid[16];
uint32_t stateBits;
uint64_t creationTime;
uint64_t modifiedTime;
uint32_t startSectorLocation;
uint64_t size;
};
struct PROPERTY_SET_STREAM_HDR
{
unsigned char byteOrder[2];
uint16_t version;
uint32_t systemIdentifier;
unsigned char clsid[16];
uint32_t numPropertySets;
struct
{
char fmtid[16];
uint32_t offset;
} propertySetInfo[1];
};
struct PROPERTY_SET_HDR
{
uint32_t size;
uint32_t NumProperties;
struct
{
uint32_t id;
uint32_t offset;
} propertyIdentifierAndOffset[1];
};
#pragma pack(pop)
const size_t MAXREGSECT = 0xFFFFFFFA;
struct helper
{
static uint32_t ParseUint32(const void* buffer)
{
return *static_cast<const uint32_t*>(buffer);
}
};
typedef std::basic_string<uint16_t> utf16string;
typedef std::function<int(const COMPOUND_FILE_ENTRY*, const utf16string& dir, int level)>
EnumFilesCallback;
class CompoundFileReader
{
public:
CompoundFileReader(const void* buffer, size_t len)
: m_buffer(static_cast<const unsigned char*>(buffer))
, m_bufferLen(len)
, m_hdr(static_cast<const COMPOUND_FILE_HDR*>(buffer))
, m_sectorSize(512)
, m_minisectorSize(64)
, m_miniStreamStartSector(0)
{
if (buffer == NULL || len == 0) throw std::invalid_argument("");
if (m_bufferLen < sizeof(*m_hdr) ||
memcmp(m_hdr->signature, "\xD0\xCF\x11\xE0\xA1\xB1\x1A\xE1", 8) != 0)
{
throw WrongFormat();
}
m_sectorSize = m_hdr->majorVersion == 3 ? 512 : 4096;
// The file must contains at least 3 sectors
if (m_bufferLen < m_sectorSize * 3) throw FileCorrupted();
const COMPOUND_FILE_ENTRY* root = GetEntry(0);
if (root == NULL) throw FileCorrupted();
m_miniStreamStartSector = root->startSectorLocation;
}
/// Get entry (directory or file) by its ID.
/// Pass "0" to get the root directory entry. -- This is the start point to navigate the compound file.
/// Use the returned object to access child entries.
const COMPOUND_FILE_ENTRY* GetEntry(size_t entryID) const
{
if (entryID == 0xFFFFFFFF)
{
return NULL;
}
if (m_bufferLen / sizeof(COMPOUND_FILE_ENTRY) <= entryID)
{
throw std::invalid_argument("");
}
size_t sector = 0;
size_t offset = 0;
LocateFinalSector(m_hdr->firstDirectorySectorLocation, entryID * sizeof(COMPOUND_FILE_ENTRY), &sector, &offset);
return reinterpret_cast<const COMPOUND_FILE_ENTRY*>(SectorOffsetToAddress(sector, offset));
}
const COMPOUND_FILE_ENTRY* GetRootEntry() const
{
return GetEntry(0);
}
const COMPOUND_FILE_HDR* GetFileInfo() const
{
return m_hdr;
}
/// Get file(stream) data start with "offset".
/// The buffer must have enough space to store "len" bytes. Typically "len" is derived by the steam length.
void ReadFile(const COMPOUND_FILE_ENTRY* entry, size_t offset, char* buffer, size_t len) const
{
if (entry->size < offset || entry->size - offset < len) throw std::invalid_argument("");
if (entry->size < m_hdr->miniStreamCutoffSize)
{
ReadMiniStream(entry->startSectorLocation, offset, buffer, len);
}
else
{
ReadStream(entry->startSectorLocation, offset, buffer, len);
}
}
bool IsPropertyStream(const COMPOUND_FILE_ENTRY* entry) const
{
// defined in [MS-OLEPS] 2.23 "Property Set Stream and Storage Names"
return entry->name[0] == 5;
}
bool IsStream(const COMPOUND_FILE_ENTRY* entry) const
{
return entry->type == 2;
}
void EnumFiles(const COMPOUND_FILE_ENTRY* entry, int maxLevel, EnumFilesCallback callback) const
{
utf16string dir;
EnumNodes(GetEntry(entry->childID), 0, maxLevel, dir, callback);
}
private:
// Enum entries with same level, including 'entry' itself
void EnumNodes(const COMPOUND_FILE_ENTRY* entry, int currentLevel, int maxLevel,
const utf16string& dir, EnumFilesCallback callback) const
{
if (maxLevel > 0 && currentLevel >= maxLevel)
return;
if (entry == nullptr)
return;
if( callback(entry, dir, currentLevel + 1) != 0 )
return;
const COMPOUND_FILE_ENTRY* child = GetEntry(entry->childID);
if (child != nullptr)
{
utf16string newDir = dir;
if (dir.length() != 0)
newDir.append(1, '\n');
newDir.append(entry->name, entry->nameLen / 2);
EnumNodes(GetEntry(entry->childID), currentLevel + 1, maxLevel, newDir, callback);
}
EnumNodes(GetEntry(entry->leftSiblingID), currentLevel, maxLevel, dir, callback);
EnumNodes(GetEntry(entry->rightSiblingID), currentLevel, maxLevel, dir, callback);
}
void ReadStream(size_t sector, size_t offset, char* buffer, size_t len) const
{
LocateFinalSector(sector, offset, &sector, &offset);
// copy as many as possible in each step
// copylen typically iterate as: m_sectorSize - offset --> m_sectorSize --> m_sectorSize --> ... --> remaining
while (len > 0)
{
const unsigned char* src = SectorOffsetToAddress(sector, offset);
size_t copylen = std::min(len, m_sectorSize - offset);
if (m_buffer + m_bufferLen < src + copylen) throw FileCorrupted();
memcpy(buffer, src, copylen);
buffer += copylen;
len -= copylen;
sector = GetNextSector(sector);
offset = 0;
}
}
// Same logic as "ReadStream" except that use MiniStream functions instead
void ReadMiniStream(size_t sector, size_t offset, char* buffer, size_t len) const
{
LocateFinalMiniSector(sector, offset, &sector, &offset);
// copy as many as possible in each step
// copylen typically iterate as: m_sectorSize - offset --> m_sectorSize --> m_sectorSize --> ... --> remaining
while (len > 0)
{
const unsigned char* src = MiniSectorOffsetToAddress(sector, offset);
size_t copylen = std::min(len, m_minisectorSize - offset);
if (m_buffer + m_bufferLen < src + copylen) throw FileCorrupted();
memcpy(buffer, src, copylen);
buffer += copylen;
len -= copylen;
sector = GetNextMiniSector(sector);
offset = 0;
}
}
size_t GetNextSector(size_t sector) const
{
// lookup FAT
size_t entriesPerSector = m_sectorSize / 4;
size_t fatSectorNumber = sector / entriesPerSector;
size_t fatSectorLocation = GetFATSectorLocation(fatSectorNumber);
return helper::ParseUint32(SectorOffsetToAddress(fatSectorLocation, sector % entriesPerSector * 4));
}
size_t GetNextMiniSector(size_t miniSector) const
{
size_t sector, offset;
LocateFinalSector(m_hdr->firstMiniFATSectorLocation, miniSector * 4, &sector, &offset);
return helper::ParseUint32(SectorOffsetToAddress(sector, offset));
}
// Get absolute address from sector and offset.
const unsigned char* SectorOffsetToAddress(size_t sector, size_t offset) const
{
if (sector >= MAXREGSECT ||
offset >= m_sectorSize ||
m_bufferLen <= static_cast<uint64_t>(m_sectorSize) * sector + m_sectorSize + offset)
{
throw FileCorrupted();
}
return m_buffer + m_sectorSize + m_sectorSize * sector + offset;
}
const unsigned char* MiniSectorOffsetToAddress(size_t sector, size_t offset) const
{
if (sector >= MAXREGSECT ||
offset >= m_minisectorSize ||
m_bufferLen <= static_cast<uint64_t>(m_minisectorSize) * sector + offset)
{
throw FileCorrupted();
}
LocateFinalSector(m_miniStreamStartSector, sector * m_minisectorSize + offset, &sector, &offset);
return SectorOffsetToAddress(sector, offset);
}
// Locate the final sector/offset when original offset expands multiple sectors
void LocateFinalSector(size_t sector, size_t offset, size_t* finalSector, size_t* finalOffset) const
{
while (offset >= m_sectorSize)
{
offset -= m_sectorSize;
sector = GetNextSector(sector);
}
*finalSector = sector;
*finalOffset = offset;
}
void LocateFinalMiniSector(size_t sector, size_t offset, size_t* finalSector, size_t* finalOffset) const
{
while (offset >= m_minisectorSize)
{
offset -= m_minisectorSize;
sector = GetNextMiniSector(sector);
}
*finalSector = sector;
*finalOffset = offset;
}
size_t GetFATSectorLocation(size_t fatSectorNumber) const
{
if (fatSectorNumber < 109)
{
return m_hdr->headerDIFAT[fatSectorNumber];
}
else
{
fatSectorNumber -= 109;
size_t entriesPerSector = m_sectorSize / 4 - 1;
size_t difatSectorLocation = m_hdr->firstDIFATSectorLocation;
while (fatSectorNumber >= entriesPerSector)
{
fatSectorNumber -= entriesPerSector;
const unsigned char* addr = SectorOffsetToAddress(difatSectorLocation, m_sectorSize - 4);
difatSectorLocation = helper::ParseUint32(addr);
}
return helper::ParseUint32(SectorOffsetToAddress(difatSectorLocation, fatSectorNumber * 4));
}
}
private:
const unsigned char * m_buffer;
size_t m_bufferLen;
const COMPOUND_FILE_HDR* m_hdr;
size_t m_sectorSize;
size_t m_minisectorSize;
size_t m_miniStreamStartSector;
};
class PropertySet
{
public:
PropertySet(const void* buffer, size_t len, const char* fmtid)
: m_buffer(static_cast<const unsigned char*>(buffer))
, m_bufferLen(len)
, m_hdr(reinterpret_cast<const PROPERTY_SET_HDR*>(buffer))
, m_fmtid(fmtid)
{
if (m_bufferLen < sizeof(*m_hdr) ||
m_bufferLen < sizeof(*m_hdr) + (m_hdr->NumProperties - 1) * sizeof(m_hdr->propertyIdentifierAndOffset[0]))
{
throw FileCorrupted();
}
}
/// return the string property in UTF-16 format
const uint16_t* GetStringProperty(uint32_t propertyID)
{
for (uint32_t i = 0; i < m_hdr->NumProperties; i++)
{
if (m_hdr->propertyIdentifierAndOffset[i].id == propertyID)
{
uint32_t offset = m_hdr->propertyIdentifierAndOffset[i].offset;
if (m_bufferLen < offset + 8) throw FileCorrupted();
uint32_t stringLengthInChar = helper::ParseUint32(m_buffer + offset + 4);
if (m_bufferLen < offset + 8 + stringLengthInChar*2) throw FileCorrupted();
return reinterpret_cast<const uint16_t*>(m_buffer + offset + 8);
}
}
return NULL;
}
/// Note: Getting property of types other than "string" is not implemented yet.
/// However most other types are simpler than string so can be easily added. see [MS-OLEPS]
const char* GetFmtID()
{
return m_fmtid;
}
private:
const unsigned char* m_buffer;
size_t m_bufferLen;
const PROPERTY_SET_HDR* m_hdr;
const char* m_fmtid; // 16 bytes
};
class PropertySetStream
{
public:
PropertySetStream(const void* buffer, size_t len)
: m_buffer(static_cast<const unsigned char*>(buffer))
, m_bufferLen(len)
, m_hdr(reinterpret_cast<const PROPERTY_SET_STREAM_HDR*>(buffer))
{
if (m_bufferLen < sizeof(*m_hdr) ||
m_bufferLen < sizeof(*m_hdr) + (m_hdr->numPropertySets - 1) * sizeof(m_hdr->propertySetInfo[0]))
{
throw FileCorrupted();
}
}
size_t GetPropertySetCount()
{
return m_hdr->numPropertySets;
}
PropertySet GetPropertySet(size_t index)
{
if (index >= GetPropertySetCount()) throw FileCorrupted();
uint32_t offset = m_hdr->propertySetInfo[index].offset;
if (m_bufferLen < offset + 4) throw FileCorrupted();
uint32_t size = helper::ParseUint32(m_buffer + offset);
if (m_bufferLen < offset + size) throw FileCorrupted();
return PropertySet(m_buffer + offset, size, m_hdr->propertySetInfo[index].fmtid);
}
private:
const unsigned char * m_buffer;
size_t m_bufferLen;
const PROPERTY_SET_STREAM_HDR* m_hdr;
};
}