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nest-open-source / nest-cam / 4320010 / gptfdisk / refs/heads/master / . / gptfdisk / gpt.cc
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/* gpt.cc -- Functions for loading, saving, and manipulating legacy MBR and GPT partition
data. */
/* By Rod Smith, initial coding January to February, 2009 */
/* This program is copyright (c) 2009-2013 by Roderick W. Smith. It is distributed
under the terms of the GNU GPL version 2, as detailed in the COPYING file. */
#define __STDC_LIMIT_MACROS
#ifndef __STDC_CONSTANT_MACROS
#define __STDC_CONSTANT_MACROS
#endif
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <fcntl.h>
#include <string.h>
#include <math.h>
#include <time.h>
#include <sys/stat.h>
#include <errno.h>
#include <iostream>
#include <algorithm>
#include "crc32.h"
#include "gpt.h"
#include "bsd.h"
#include "support.h"
#include "parttypes.h"
#include "attributes.h"
#include "diskio.h"
using namespace std;
#ifdef __FreeBSD__
#define log2(x) (log(x) / M_LN2)
#endif // __FreeBSD__
#ifdef _MSC_VER
#define log2(x) (log((double) x) / log(2.0))
#endif // Microsoft Visual C++
#ifdef EFI
// in UEFI mode MMX registers are not yet available so using the
// x86_64 ABI to move "double" values around is not an option.
#ifdef log2
#undef log2
#endif
#define log2(x) log2_32( x )
static inline uint32_t log2_32(uint32_t v) {
int r = -1;
while (v >= 1) {
r++;
v >>= 1;
}
return r;
}
#endif
/****************************************
* *
* GPTData class and related structures *
* *
****************************************/
// Default constructor
GPTData::GPTData(void) {
blockSize = SECTOR_SIZE; // set a default
diskSize = 0;
partitions = NULL;
state = gpt_valid;
device = "";
justLooking = 0;
mainCrcOk = 0;
secondCrcOk = 0;
mainPartsCrcOk = 0;
secondPartsCrcOk = 0;
apmFound = 0;
bsdFound = 0;
sectorAlignment = MIN_AF_ALIGNMENT; // Align partitions on 4096-byte boundaries by default
beQuiet = 0;
whichWasUsed = use_new;
mainHeader.numParts = 0;
numParts = 0;
SetGPTSize(NUM_GPT_ENTRIES);
// Initialize CRC functions...
chksum_crc32gentab();
} // GPTData default constructor
// The following constructor loads GPT data from a device file
GPTData::GPTData(string filename) {
blockSize = SECTOR_SIZE; // set a default
diskSize = 0;
partitions = NULL;
state = gpt_invalid;
device = "";
justLooking = 0;
mainCrcOk = 0;
secondCrcOk = 0;
mainPartsCrcOk = 0;
secondPartsCrcOk = 0;
apmFound = 0;
bsdFound = 0;
sectorAlignment = MIN_AF_ALIGNMENT; // Align partitions on 4096-byte boundaries by default
beQuiet = 0;
whichWasUsed = use_new;
mainHeader.numParts = 0;
numParts = 0;
// Initialize CRC functions...
chksum_crc32gentab();
if (!LoadPartitions(filename))
exit(2);
} // GPTData(string filename) constructor
// Destructor
GPTData::~GPTData(void) {
delete[] partitions;
} // GPTData destructor
// Assignment operator
GPTData & GPTData::operator=(const GPTData & orig) {
uint32_t i;
mainHeader = orig.mainHeader;
numParts = orig.numParts;
secondHeader = orig.secondHeader;
protectiveMBR = orig.protectiveMBR;
device = orig.device;
blockSize = orig.blockSize;
diskSize = orig.diskSize;
state = orig.state;
justLooking = orig.justLooking;
mainCrcOk = orig.mainCrcOk;
secondCrcOk = orig.secondCrcOk;
mainPartsCrcOk = orig.mainPartsCrcOk;
secondPartsCrcOk = orig.secondPartsCrcOk;
apmFound = orig.apmFound;
bsdFound = orig.bsdFound;
sectorAlignment = orig.sectorAlignment;
beQuiet = orig.beQuiet;
whichWasUsed = orig.whichWasUsed;
myDisk.OpenForRead(orig.myDisk.GetName());
delete[] partitions;
partitions = new GPTPart [numParts];
if (partitions == NULL) {
cerr << "Error! Could not allocate memory for partitions in GPTData::operator=()!\n"
<< "Terminating!\n";
exit(1);
} // if
for (i = 0; i < numParts; i++) {
partitions[i] = orig.partitions[i];
} // for
return *this;
} // GPTData::operator=()
/*********************************************************************
* *
* Begin functions that verify data, or that adjust the verification *
* information (compute CRCs, rebuild headers) *
* *
*********************************************************************/
// Perform detailed verification, reporting on any problems found, but
// do *NOT* recover from these problems. Returns the total number of
// problems identified.
int GPTData::Verify(void) {
int problems = 0, alignProbs = 0;
uint32_t i, numSegments;
uint64_t totalFree, largestSegment;
// First, check for CRC errors in the GPT data....
if (!mainCrcOk) {
problems++;
cout << "\nProblem: The CRC for the main GPT header is invalid. The main GPT header may\n"
<< "be corrupt. Consider loading the backup GPT header to rebuild the main GPT\n"
<< "header ('b' on the recovery & transformation menu). This report may be a false\n"
<< "alarm if you've already corrected other problems.\n";
} // if
if (!mainPartsCrcOk) {
problems++;
cout << "\nProblem: The CRC for the main partition table is invalid. This table may be\n"
<< "corrupt. Consider loading the backup partition table ('c' on the recovery &\n"
<< "transformation menu). This report may be a false alarm if you've already\n"
<< "corrected other problems.\n";
} // if
if (!secondCrcOk) {
problems++;
cout << "\nProblem: The CRC for the backup GPT header is invalid. The backup GPT header\n"
<< "may be corrupt. Consider using the main GPT header to rebuild the backup GPT\n"
<< "header ('d' on the recovery & transformation menu). This report may be a false\n"
<< "alarm if you've already corrected other problems.\n";
} // if
if (!secondPartsCrcOk) {
problems++;
cout << "\nCaution: The CRC for the backup partition table is invalid. This table may\n"
<< "be corrupt. This program will automatically create a new backup partition\n"
<< "table when you save your partitions.\n";
} // if
// Now check that the main and backup headers both point to themselves....
if (mainHeader.currentLBA != 1) {
problems++;
cout << "\nProblem: The main header's self-pointer doesn't point to itself. This problem\n"
<< "is being automatically corrected, but it may be a symptom of more serious\n"
<< "problems. Think carefully before saving changes with 'w' or using this disk.\n";
mainHeader.currentLBA = 1;
} // if
if (secondHeader.currentLBA != (diskSize - UINT64_C(1))) {
problems++;
cout << "\nProblem: The secondary header's self-pointer indicates that it doesn't reside\n"
<< "at the end of the disk. If you've added a disk to a RAID array, use the 'e'\n"
<< "option on the experts' menu to adjust the secondary header's and partition\n"
<< "table's locations.\n";
} // if
// Now check that critical main and backup GPT entries match each other
if (mainHeader.currentLBA != secondHeader.backupLBA) {
problems++;
cout << "\nProblem: main GPT header's current LBA pointer (" << mainHeader.currentLBA
<< ") doesn't\nmatch the backup GPT header's alternate LBA pointer("
<< secondHeader.backupLBA << ").\n";
} // if
if (mainHeader.backupLBA != secondHeader.currentLBA) {
problems++;
cout << "\nProblem: main GPT header's backup LBA pointer (" << mainHeader.backupLBA
<< ") doesn't\nmatch the backup GPT header's current LBA pointer ("
<< secondHeader.currentLBA << ").\n"
<< "The 'e' option on the experts' menu may fix this problem.\n";
} // if
if (mainHeader.firstUsableLBA != secondHeader.firstUsableLBA) {
problems++;
cout << "\nProblem: main GPT header's first usable LBA pointer (" << mainHeader.firstUsableLBA
<< ") doesn't\nmatch the backup GPT header's first usable LBA pointer ("
<< secondHeader.firstUsableLBA << ")\n";
} // if
if (mainHeader.lastUsableLBA != secondHeader.lastUsableLBA) {
problems++;
cout << "\nProblem: main GPT header's last usable LBA pointer (" << mainHeader.lastUsableLBA
<< ") doesn't\nmatch the backup GPT header's last usable LBA pointer ("
<< secondHeader.lastUsableLBA << ")\n"
<< "The 'e' option on the experts' menu can probably fix this problem.\n";
} // if
if ((mainHeader.diskGUID != secondHeader.diskGUID)) {
problems++;
cout << "\nProblem: main header's disk GUID (" << mainHeader.diskGUID
<< ") doesn't\nmatch the backup GPT header's disk GUID ("
<< secondHeader.diskGUID << ")\n"
<< "You should use the 'b' or 'd' option on the recovery & transformation menu to\n"
<< "select one or the other header.\n";
} // if
if (mainHeader.numParts != secondHeader.numParts) {
problems++;
cout << "\nProblem: main GPT header's number of partitions (" << mainHeader.numParts
<< ") doesn't\nmatch the backup GPT header's number of partitions ("
<< secondHeader.numParts << ")\n"
<< "Resizing the partition table ('s' on the experts' menu) may help.\n";
} // if
if (mainHeader.sizeOfPartitionEntries != secondHeader.sizeOfPartitionEntries) {
problems++;
cout << "\nProblem: main GPT header's size of partition entries ("
<< mainHeader.sizeOfPartitionEntries << ") doesn't\n"
<< "match the backup GPT header's size of partition entries ("
<< secondHeader.sizeOfPartitionEntries << ")\n"
<< "You should use the 'b' or 'd' option on the recovery & transformation menu to\n"
<< "select one or the other header.\n";
} // if
// Now check for a few other miscellaneous problems...
// Check that the disk size will hold the data...
if (mainHeader.backupLBA >= diskSize) {
problems++;
cout << "\nProblem: Disk is too small to hold all the data!\n"
<< "(Disk size is " << diskSize << " sectors, needs to be "
<< mainHeader.backupLBA + UINT64_C(1) << " sectors.)\n"
<< "The 'e' option on the experts' menu may fix this problem.\n";
} // if
if ((mainHeader.lastUsableLBA >= diskSize) || (mainHeader.lastUsableLBA > mainHeader.backupLBA)) {
problems++;
cout << "\nProblem: GPT claims the disk is larger than it is! (Claimed last usable\n"
<< "sector is " << mainHeader.lastUsableLBA << ", but backup header is at\n"
<< mainHeader.backupLBA << " and disk size is " << diskSize << " sectors.\n"
<< "The 'e' option on the experts' menu will probably fix this problem\n";
}
// Check for overlapping partitions....
problems += FindOverlaps();
// Check for insane partitions (start after end, hugely big, etc.)
problems += FindInsanePartitions();
// Check for mismatched MBR and GPT partitions...
problems += FindHybridMismatches();
// Check for MBR-specific problems....
problems += VerifyMBR();
// Check for a 0xEE protective partition that's marked as active....
if (protectiveMBR.IsEEActive()) {
cout << "\nWarning: The 0xEE protective partition in the MBR is marked as active. This is\n"
<< "technically a violation of the GPT specification, and can cause some EFIs to\n"
<< "ignore the disk, but it is required to boot from a GPT disk on some BIOS-based\n"
<< "computers. You can clear this flag by creating a fresh protective MBR using\n"
<< "the 'n' option on the experts' menu.\n";
}
// Verify that partitions don't run into GPT data areas....
problems += CheckGPTSize();
if (!protectiveMBR.DoTheyFit()) {
cout << "\nPartition(s) in the protective MBR are too big for the disk! Creating a\n"
<< "fresh protective or hybrid MBR is recommended.\n";
problems++;
}
// Check that partitions are aligned on proper boundaries (for WD Advanced
// Format and similar disks)....
for (i = 0; i < numParts; i++) {
if ((partitions[i].IsUsed()) && (partitions[i].GetFirstLBA() % sectorAlignment) != 0) {
cout << "\nCaution: Partition " << i + 1 << " doesn't begin on a "
<< sectorAlignment << "-sector boundary. This may\nresult "
<< "in degraded performance on some modern (2009 and later) hard disks.\n";
alignProbs++;
} // if
} // for
if (alignProbs > 0)
cout << "\nConsult http://www.ibm.com/developerworks/linux/library/l-4kb-sector-disks/\n"
<< "for information on disk alignment.\n";
// Now compute available space, but only if no problems found, since
// problems could affect the results
if (problems == 0) {
totalFree = FindFreeBlocks(&numSegments, &largestSegment);
cout << "\nNo problems found. " << totalFree << " free sectors ("
<< BytesToIeee(totalFree, blockSize) << ") available in "
<< numSegments << "\nsegments, the largest of which is "
<< largestSegment << " (" << BytesToIeee(largestSegment, blockSize)
<< ") in size.\n";
} else {
cout << "\nIdentified " << problems << " problems!\n";
} // if/else
return (problems);
} // GPTData::Verify()
// Checks to see if the GPT tables overrun existing partitions; if they
// do, issues a warning but takes no action. Returns number of problems
// detected (0 if OK, 1 to 2 if problems).
int GPTData::CheckGPTSize(void) {
uint64_t overlap, firstUsedBlock, lastUsedBlock;
uint32_t i;
int numProbs = 0;
// first, locate the first & last used blocks
firstUsedBlock = UINT64_MAX;
lastUsedBlock = 0;
for (i = 0; i < numParts; i++) {
if (partitions[i].IsUsed()) {
if (partitions[i].GetFirstLBA() < firstUsedBlock)
firstUsedBlock = partitions[i].GetFirstLBA();
if (partitions[i].GetLastLBA() > lastUsedBlock) {
lastUsedBlock = partitions[i].GetLastLBA();
} // if
} // if
} // for
// If the disk size is 0 (the default), then it means that various
// variables aren't yet set, so the below tests will be useless;
// therefore we should skip everything
if (diskSize != 0) {
if (mainHeader.firstUsableLBA > firstUsedBlock) {
overlap = mainHeader.firstUsableLBA - firstUsedBlock;
cout << "Warning! Main partition table overlaps the first partition by "
<< overlap << " blocks!\n";
if (firstUsedBlock > 2) {
cout << "Try reducing the partition table size by " << overlap * 4
<< " entries.\n(Use the 's' item on the experts' menu.)\n";
} else {
cout << "You will need to delete this partition or resize it in another utility.\n";
} // if/else
numProbs++;
} // Problem at start of disk
if (mainHeader.lastUsableLBA < lastUsedBlock) {
overlap = lastUsedBlock - mainHeader.lastUsableLBA;
cout << "\nWarning! Secondary partition table overlaps the last partition by\n"
<< overlap << " blocks!\n";
if (lastUsedBlock > (diskSize - 2)) {
cout << "You will need to delete this partition or resize it in another utility.\n";
} else {
cout << "Try reducing the partition table size by " << overlap * 4
<< " entries.\n(Use the 's' item on the experts' menu.)\n";
} // if/else
numProbs++;
} // Problem at end of disk
} // if (diskSize != 0)
return numProbs;
} // GPTData::CheckGPTSize()
// Check the validity of the GPT header. Returns 1 if the main header
// is valid, 2 if the backup header is valid, 3 if both are valid, and
// 0 if neither is valid. Note that this function checks the GPT signature,
// revision value, and CRCs in both headers.
int GPTData::CheckHeaderValidity(void) {
int valid = 3;
cout.setf(ios::uppercase);
cout.fill('0');
// Note: failed GPT signature checks produce no error message because
// a message is displayed in the ReversePartitionBytes() function
if ((mainHeader.signature != GPT_SIGNATURE) || (!CheckHeaderCRC(&mainHeader, 1))) {
valid -= 1;
} else if ((mainHeader.revision != 0x00010000) && valid) {
valid -= 1;
cout << "Unsupported GPT version in main header; read 0x";
cout.width(8);
cout << hex << mainHeader.revision << ", should be\n0x";
cout.width(8);
cout << UINT32_C(0x00010000) << dec << "\n";
} // if/else/if
if ((secondHeader.signature != GPT_SIGNATURE) || (!CheckHeaderCRC(&secondHeader))) {
valid -= 2;
} else if ((secondHeader.revision != 0x00010000) && valid) {
valid -= 2;
cout << "Unsupported GPT version in backup header; read 0x";
cout.width(8);
cout << hex << secondHeader.revision << ", should be\n0x";
cout.width(8);
cout << UINT32_C(0x00010000) << dec << "\n";
} // if/else/if
// Check for an Apple disk signature
if (((mainHeader.signature << 32) == APM_SIGNATURE1) ||
(mainHeader.signature << 32) == APM_SIGNATURE2) {
apmFound = 1; // Will display warning message later
} // if
cout.fill(' ');
return valid;
} // GPTData::CheckHeaderValidity()
// Check the header CRC to see if it's OK...
// Note: Must be called with header in platform-ordered byte order.
// Returns 1 if header's computed CRC matches the stored value, 0 if the
// computed and stored values don't match
int GPTData::CheckHeaderCRC(struct GPTHeader* header, int warn) {
uint32_t oldCRC, newCRC, hSize;
uint8_t *temp;
// Back up old header CRC and then blank it, since it must be 0 for
// computation to be valid
oldCRC = header->headerCRC;
header->headerCRC = UINT32_C(0);
hSize = header->headerSize;
if (IsLittleEndian() == 0)
ReverseHeaderBytes(header);
if ((hSize > blockSize) || (hSize < HEADER_SIZE)) {
if (warn) {
cerr << "\aWarning! Header size is specified as " << hSize << ", which is invalid.\n";
cerr << "Setting the header size for CRC computation to " << HEADER_SIZE << "\n";
} // if
hSize = HEADER_SIZE;
} else if ((hSize > sizeof(GPTHeader)) && warn) {
cout << "\aCaution! Header size for CRC check is " << hSize << ", which is greater than " << sizeof(GPTHeader) << ".\n";
cout << "If stray data exists after the header on the header sector, it will be ignored,\n"
<< "which may result in a CRC false alarm.\n";
} // if/elseif
temp = new uint8_t[hSize];
if (temp != NULL) {
memset(temp, 0, hSize);
if (hSize < sizeof(GPTHeader))
memcpy(temp, header, hSize);
else
memcpy(temp, header, sizeof(GPTHeader));
newCRC = chksum_crc32((unsigned char*) temp, hSize);
delete[] temp;
} else {
cerr << "Could not allocate memory in GPTData::CheckHeaderCRC()! Aborting!\n";
exit(1);
}
if (IsLittleEndian() == 0)
ReverseHeaderBytes(header);
header->headerCRC = oldCRC;
return (oldCRC == newCRC);
} // GPTData::CheckHeaderCRC()
// Recompute all the CRCs. Must be called before saving if any changes have
// been made. Must be called on platform-ordered data (this function reverses
// byte order and then undoes that reversal.)
void GPTData::RecomputeCRCs(void) {
uint32_t crc, hSize;
int littleEndian = 1;
// If the header size is bigger than the GPT header data structure, reset it;
// otherwise, set both header sizes to whatever the main one is....
if (mainHeader.headerSize > sizeof(GPTHeader))
hSize = secondHeader.headerSize = mainHeader.headerSize = HEADER_SIZE;
else
hSize = secondHeader.headerSize = mainHeader.headerSize;
if ((littleEndian = IsLittleEndian()) == 0) {
ReversePartitionBytes();
ReverseHeaderBytes(&mainHeader);
ReverseHeaderBytes(&secondHeader);
} // if
// Compute CRC of partition tables & store in main and secondary headers
crc = chksum_crc32((unsigned char*) partitions, numParts * GPT_SIZE);
mainHeader.partitionEntriesCRC = crc;
secondHeader.partitionEntriesCRC = crc;
if (littleEndian == 0) {
ReverseBytes(&mainHeader.partitionEntriesCRC, 4);
ReverseBytes(&secondHeader.partitionEntriesCRC, 4);
} // if
// Zero out GPT headers' own CRCs (required for correct computation)
mainHeader.headerCRC = 0;
secondHeader.headerCRC = 0;
crc = chksum_crc32((unsigned char*) &mainHeader, hSize);
if (littleEndian == 0)
ReverseBytes(&crc, 4);
mainHeader.headerCRC = crc;
crc = chksum_crc32((unsigned char*) &secondHeader, hSize);
if (littleEndian == 0)
ReverseBytes(&crc, 4);
secondHeader.headerCRC = crc;
if (littleEndian == 0) {
ReverseHeaderBytes(&mainHeader);
ReverseHeaderBytes(&secondHeader);
ReversePartitionBytes();
} // if
} // GPTData::RecomputeCRCs()
// Rebuild the main GPT header, using the secondary header as a model.
// Typically called when the main header has been found to be corrupt.
void GPTData::RebuildMainHeader(void) {
mainHeader.signature = GPT_SIGNATURE;
mainHeader.revision = secondHeader.revision;
mainHeader.headerSize = secondHeader.headerSize;
mainHeader.headerCRC = UINT32_C(0);
mainHeader.reserved = secondHeader.reserved;
mainHeader.currentLBA = secondHeader.backupLBA;
mainHeader.backupLBA = secondHeader.currentLBA;
mainHeader.firstUsableLBA = secondHeader.firstUsableLBA;
mainHeader.lastUsableLBA = secondHeader.lastUsableLBA;
mainHeader.diskGUID = secondHeader.diskGUID;
mainHeader.partitionEntriesLBA = UINT64_C(2);
mainHeader.numParts = secondHeader.numParts;
mainHeader.sizeOfPartitionEntries = secondHeader.sizeOfPartitionEntries;
mainHeader.partitionEntriesCRC = secondHeader.partitionEntriesCRC;
memcpy(mainHeader.reserved2, secondHeader.reserved2, sizeof(mainHeader.reserved2));
mainCrcOk = secondCrcOk;
SetGPTSize(mainHeader.numParts, 0);
} // GPTData::RebuildMainHeader()
// Rebuild the secondary GPT header, using the main header as a model.
void GPTData::RebuildSecondHeader(void) {
secondHeader.signature = GPT_SIGNATURE;
secondHeader.revision = mainHeader.revision;
secondHeader.headerSize = mainHeader.headerSize;
secondHeader.headerCRC = UINT32_C(0);
secondHeader.reserved = mainHeader.reserved;
secondHeader.currentLBA = mainHeader.backupLBA;
secondHeader.backupLBA = mainHeader.currentLBA;
secondHeader.firstUsableLBA = mainHeader.firstUsableLBA;
secondHeader.lastUsableLBA = mainHeader.lastUsableLBA;
secondHeader.diskGUID = mainHeader.diskGUID;
secondHeader.partitionEntriesLBA = secondHeader.lastUsableLBA + UINT64_C(1);
secondHeader.numParts = mainHeader.numParts;
secondHeader.sizeOfPartitionEntries = mainHeader.sizeOfPartitionEntries;
secondHeader.partitionEntriesCRC = mainHeader.partitionEntriesCRC;
memcpy(secondHeader.reserved2, mainHeader.reserved2, sizeof(secondHeader.reserved2));
secondCrcOk = mainCrcOk;
SetGPTSize(secondHeader.numParts, 0);
} // GPTData::RebuildSecondHeader()
// Search for hybrid MBR entries that have no corresponding GPT partition.
// Returns number of such mismatches found
int GPTData::FindHybridMismatches(void) {
int i, found, numFound = 0;
uint32_t j;
uint64_t mbrFirst, mbrLast;
for (i = 0; i < 4; i++) {
if ((protectiveMBR.GetType(i) != 0xEE) && (protectiveMBR.GetType(i) != 0x00)) {
j = 0;
found = 0;
mbrFirst = (uint64_t) protectiveMBR.GetFirstSector(i);
mbrLast = mbrFirst + (uint64_t) protectiveMBR.GetLength(i) - UINT64_C(1);
do {
if ((j < numParts) && (partitions[j].GetFirstLBA() == mbrFirst) &&
(partitions[j].GetLastLBA() == mbrLast) && (partitions[j].IsUsed()))
found = 1;
j++;
} while ((!found) && (j < numParts));
if (!found) {
numFound++;
cout << "\nWarning! Mismatched GPT and MBR partition! MBR partition "
<< i + 1 << ", of type 0x";
cout.fill('0');
cout.setf(ios::uppercase);
cout.width(2);
cout << hex << (int) protectiveMBR.GetType(i) << ",\n"
<< "has no corresponding GPT partition! You may continue, but this condition\n"
<< "might cause data loss in the future!\a\n" << dec;
cout.fill(' ');
} // if
} // if
} // for
return numFound;
} // GPTData::FindHybridMismatches
// Find overlapping partitions and warn user about them. Returns number of
// overlapping partitions.
// Returns number of overlapping segments found.
int GPTData::FindOverlaps(void) {
int problems = 0;
uint32_t i, j;
for (i = 1; i < numParts; i++) {
for (j = 0; j < i; j++) {
if ((partitions[i].IsUsed()) && (partitions[j].IsUsed()) &&
(partitions[i].DoTheyOverlap(partitions[j]))) {
problems++;
cout << "\nProblem: partitions " << i + 1 << " and " << j + 1 << " overlap:\n";
cout << " Partition " << i + 1 << ": " << partitions[i].GetFirstLBA()
<< " to " << partitions[i].GetLastLBA() << "\n";
cout << " Partition " << j + 1 << ": " << partitions[j].GetFirstLBA()
<< " to " << partitions[j].GetLastLBA() << "\n";
} // if
} // for j...
} // for i...
return problems;
} // GPTData::FindOverlaps()
// Find partitions that are insane -- they start after they end or are too
// big for the disk. (The latter should duplicate detection of overlaps
// with GPT backup data structures, but better to err on the side of
// redundant tests than to miss something....)
// Returns number of problems found.
int GPTData::FindInsanePartitions(void) {
uint32_t i;
int problems = 0;
for (i = 0; i < numParts; i++) {
if (partitions[i].IsUsed()) {
if (partitions[i].GetFirstLBA() > partitions[i].GetLastLBA()) {
problems++;
cout << "\nProblem: partition " << i + 1 << " ends before it begins.\n";
} // if
if (partitions[i].GetLastLBA() >= diskSize) {
problems++;
cout << "\nProblem: partition " << i + 1 << " is too big for the disk.\n";
} // if
} // if
} // for
return problems;
} // GPTData::FindInsanePartitions(void)
/******************************************************************
* *
* Begin functions that load data from disk or save data to disk. *
* *
******************************************************************/
// Change the filename associated with the GPT. Used for duplicating
// the partition table to a new disk and saving backups.
// Returns 1 on success, 0 on failure.
int GPTData::SetDisk(const string & deviceFilename) {
int err, allOK = 1;
device = deviceFilename;
if (allOK && myDisk.OpenForRead(deviceFilename)) {
// store disk information....
diskSize = myDisk.DiskSize(&err);
blockSize = (uint32_t) myDisk.GetBlockSize();
} // if
protectiveMBR.SetDisk(&myDisk);
protectiveMBR.SetDiskSize(diskSize);
protectiveMBR.SetBlockSize(blockSize);
return allOK;
} // GPTData::SetDisk()
// Scan for partition data. This function loads the MBR data (regular MBR or
// protective MBR) and loads BSD disklabel data (which is probably invalid).
// It also looks for APM data, forces a load of GPT data, and summarizes
// the results.
void GPTData::PartitionScan(void) {
BSDData bsdDisklabel;
// Read the MBR & check for BSD disklabel
protectiveMBR.ReadMBRData(&myDisk);
bsdDisklabel.ReadBSDData(&myDisk, 0, diskSize - 1);
// Load the GPT data, whether or not it's valid
ForceLoadGPTData();
// Some tools create a 0xEE partition that's too big. If this is detected,
// normalize it....
if ((state == gpt_valid) && !protectiveMBR.DoTheyFit() && (protectiveMBR.GetValidity() == gpt)) {
if (!beQuiet) {
cerr << "\aThe protective MBR's 0xEE partition is oversized! Auto-repairing.\n\n";
} // if
protectiveMBR.MakeProtectiveMBR();
} // if
if (!beQuiet) {
cout << "Partition table scan:\n";
protectiveMBR.ShowState();
bsdDisklabel.ShowState();
ShowAPMState(); // Show whether there's an Apple Partition Map present
ShowGPTState(); // Show GPT status
cout << "\n";
} // if
if (apmFound) {
cout << "\n*******************************************************************\n"
<< "This disk appears to contain an Apple-format (APM) partition table!\n";
if (!justLooking) {
cout << "It will be destroyed if you continue!\n";
} // if
cout << "*******************************************************************\n\n\a";
} // if
} // GPTData::PartitionScan()
// Read GPT data from a disk.
int GPTData::LoadPartitions(const string & deviceFilename) {
BSDData bsdDisklabel;
int err, allOK = 1;
MBRValidity mbrState;
if (myDisk.OpenForRead(deviceFilename)) {
err = myDisk.OpenForWrite(deviceFilename);
if ((err == 0) && (!justLooking)) {
cout << "\aNOTE: Write test failed with error number " << errno
<< ". It will be impossible to save\nchanges to this disk's partition table!\n";
#if defined (__FreeBSD__) || defined (__FreeBSD_kernel__)
cout << "You may be able to enable writes by exiting this program, typing\n"
<< "'sysctl kern.geom.debugflags=16' at a shell prompt, and re-running this\n"
<< "program.\n";
#endif
#if defined (__APPLE__)
cout << "You may need to deactivate System Integrity Protection to use this program. See\n"
<< "https://www.quora.com/How-do-I-turn-off-the-rootless-in-OS-X-El-Capitan-10-11\n"
<< "for more information.\n";
#endif
cout << "\n";
} // if
myDisk.Close(); // Close and re-open read-only in case of bugs
} else allOK = 0; // if
if (allOK && myDisk.OpenForRead(deviceFilename)) {
// store disk information....
diskSize = myDisk.DiskSize(&err);
blockSize = (uint32_t) myDisk.GetBlockSize();
device = deviceFilename;
PartitionScan(); // Check for partition types, load GPT, & print summary
whichWasUsed = UseWhichPartitions();
switch (whichWasUsed) {
case use_mbr:
XFormPartitions();
break;
case use_bsd:
bsdDisklabel.ReadBSDData(&myDisk, 0, diskSize - 1);
// bsdDisklabel.DisplayBSDData();
ClearGPTData();
protectiveMBR.MakeProtectiveMBR(1); // clear boot area (option 1)
XFormDisklabel(&bsdDisklabel);
break;
case use_gpt:
mbrState = protectiveMBR.GetValidity();
if ((mbrState == invalid) || (mbrState == mbr))
protectiveMBR.MakeProtectiveMBR();
break;
case use_new:
ClearGPTData();
protectiveMBR.MakeProtectiveMBR();
break;
case use_abort:
allOK = 0;
cerr << "Invalid partition data!\n";
break;
} // switch
if (allOK)
CheckGPTSize();
myDisk.Close();
ComputeAlignment();
} else {
allOK = 0;
} // if/else
return (allOK);
} // GPTData::LoadPartitions()
// Loads the GPT, as much as possible. Returns 1 if this seems to have
// succeeded, 0 if there are obvious problems....
int GPTData::ForceLoadGPTData(void) {
int allOK, validHeaders, loadedTable = 1;
allOK = LoadHeader(&mainHeader, myDisk, 1, &mainCrcOk);
if (mainCrcOk && (mainHeader.backupLBA < diskSize)) {
allOK = LoadHeader(&secondHeader, myDisk, mainHeader.backupLBA, &secondCrcOk) && allOK;
} else {
allOK = LoadHeader(&secondHeader, myDisk, diskSize - UINT64_C(1), &secondCrcOk) && allOK;
if (mainCrcOk && (mainHeader.backupLBA >= diskSize))
cout << "Warning! Disk size is smaller than the main header indicates! Loading\n"
<< "secondary header from the last sector of the disk! You should use 'v' to\n"
<< "verify disk integrity, and perhaps options on the experts' menu to repair\n"
<< "the disk.\n";
} // if/else
if (!allOK)
state = gpt_invalid;
// Return valid headers code: 0 = both headers bad; 1 = main header
// good, backup bad; 2 = backup header good, main header bad;
// 3 = both headers good. Note these codes refer to valid GPT
// signatures, version numbers, and CRCs.
validHeaders = CheckHeaderValidity();
// Read partitions (from primary array)
if (validHeaders > 0) { // if at least one header is OK....
// GPT appears to be valid....
state = gpt_valid;
// We're calling the GPT valid, but there's a possibility that one
// of the two headers is corrupt. If so, use the one that seems to
// be in better shape to regenerate the bad one
if (validHeaders == 1) { // valid main header, invalid backup header
cerr << "\aCaution: invalid backup GPT header, but valid main header; regenerating\n"
<< "backup header from main header.\n\n";
RebuildSecondHeader();
state = gpt_corrupt;
secondCrcOk = mainCrcOk; // Since regenerated, use CRC validity of main
} else if (validHeaders == 2) { // valid backup header, invalid main header
cerr << "\aCaution: invalid main GPT header, but valid backup; regenerating main header\n"
<< "from backup!\n\n";
RebuildMainHeader();
state = gpt_corrupt;
mainCrcOk = secondCrcOk; // Since copied, use CRC validity of backup
} // if/else/if
// Figure out which partition table to load....
// Load the main partition table, since either its header's CRC is OK or the
// backup header's CRC is not OK....
if (mainCrcOk || !secondCrcOk) {
if (LoadMainTable() == 0)
allOK = 0;
} else { // bad main header CRC and backup header CRC is OK
state = gpt_corrupt;
if (LoadSecondTableAsMain()) {
loadedTable = 2;
cerr << "\aWarning: Invalid CRC on main header data; loaded backup partition table.\n";
} else { // backup table bad, bad main header CRC, but try main table in desperation....
if (LoadMainTable() == 0) {
allOK = 0;
loadedTable = 0;
cerr << "\a\aWarning! Unable to load either main or backup partition table!\n";
} // if
} // if/else (LoadSecondTableAsMain())
} // if/else (load partition table)
if (loadedTable == 1)
secondPartsCrcOk = CheckTable(&secondHeader);
else if (loadedTable == 2)
mainPartsCrcOk = CheckTable(&mainHeader);
else
mainPartsCrcOk = secondPartsCrcOk = 0;
// Problem with main partition table; if backup is OK, use it instead....
if (secondPartsCrcOk && secondCrcOk && !mainPartsCrcOk) {
state = gpt_corrupt;
allOK = allOK && LoadSecondTableAsMain();
mainPartsCrcOk = 0; // LoadSecondTableAsMain() resets this, so re-flag as bad
cerr << "\aWarning! Main partition table CRC mismatch! Loaded backup "
<< "partition table\ninstead of main partition table!\n\n";
} // if */
// Check for valid CRCs and warn if there are problems
if ((mainCrcOk == 0) || (secondCrcOk == 0) || (mainPartsCrcOk == 0) ||
(secondPartsCrcOk == 0)) {
cerr << "Warning! One or more CRCs don't match. You should repair the disk!\n\n";
state = gpt_corrupt;
} // if
} else {
state = gpt_invalid;
} // if/else
return allOK;
} // GPTData::ForceLoadGPTData()
// Loads the partition table pointed to by the main GPT header. The
// main GPT header in memory MUST be valid for this call to do anything
// sensible!
// Returns 1 on success, 0 on failure. CRC errors do NOT count as failure.
int GPTData::LoadMainTable(void) {
return LoadPartitionTable(mainHeader, myDisk);
} // GPTData::LoadMainTable()
// Load the second (backup) partition table as the primary partition
// table. Used in repair functions, and when starting up if the main
// partition table is damaged.
// Returns 1 on success, 0 on failure. CRC errors do NOT count as failure.
int GPTData::LoadSecondTableAsMain(void) {
return LoadPartitionTable(secondHeader, myDisk);
} // GPTData::LoadSecondTableAsMain()
// Load a single GPT header (main or backup) from the specified disk device and
// sector. Applies byte-order corrections on big-endian platforms. Sets crcOk
// value appropriately.
// Returns 1 on success, 0 on failure. Note that CRC errors do NOT qualify as
// failure.
int GPTData::LoadHeader(struct GPTHeader *header, DiskIO & disk, uint64_t sector, int *crcOk) {
int allOK = 1;
GPTHeader tempHeader;
disk.Seek(sector);
if (disk.Read(&tempHeader, 512) != 512) {
cerr << "Warning! Read error " << errno << "; strange behavior now likely!\n";
allOK = 0;
} // if
// Reverse byte order, if necessary
if (IsLittleEndian() == 0) {
ReverseHeaderBytes(&tempHeader);
} // if
*crcOk = CheckHeaderCRC(&tempHeader);
if (allOK && (numParts != tempHeader.numParts) && *crcOk) {
allOK = SetGPTSize(tempHeader.numParts, 0);
}
*header = tempHeader;
return allOK;
} // GPTData::LoadHeader
// Load a partition table (either main or secondary) from the specified disk,
// using header as a reference for what to load. If sector != 0 (the default
// is 0), loads from the specified sector; otherwise loads from the sector
// indicated in header.
// Returns 1 on success, 0 on failure. CRC errors do NOT count as failure.
int GPTData::LoadPartitionTable(const struct GPTHeader & header, DiskIO & disk, uint64_t sector) {
uint32_t sizeOfParts, newCRC;
int retval;
if (disk.OpenForRead()) {
if (sector == 0) {
retval = disk.Seek(header.partitionEntriesLBA);
} else {
retval = disk.Seek(sector);
} // if/else
if (retval == 1)
retval = SetGPTSize(header.numParts, 0);
if (retval == 1) {
sizeOfParts = header.numParts * header.sizeOfPartitionEntries;
if (disk.Read(partitions, sizeOfParts) != (int) sizeOfParts) {
cerr << "Warning! Read error " << errno << "! Misbehavior now likely!\n";
retval = 0;
} // if
newCRC = chksum_crc32((unsigned char*) partitions, sizeOfParts);
mainPartsCrcOk = secondPartsCrcOk = (newCRC == header.partitionEntriesCRC);
if (IsLittleEndian() == 0)
ReversePartitionBytes();
if (!mainPartsCrcOk) {
cout << "Caution! After loading partitions, the CRC doesn't check out!\n";
} // if
} else {
cerr << "Error! Couldn't seek to partition table!\n";
} // if/else
} else {
cerr << "Error! Couldn't open device " << device
<< " when reading partition table!\n";
retval = 0;
} // if/else
return retval;
} // GPTData::LoadPartitionsTable()
// Check the partition table pointed to by header, but don't keep it
// around.
// Returns 1 if the CRC is OK & this table matches the one already in memory,
// 0 if not or if there was a read error.
int GPTData::CheckTable(struct GPTHeader *header) {
uint32_t sizeOfParts, newCRC;
GPTPart *partsToCheck;
GPTHeader *otherHeader;
int allOK = 0;
// Load partition table into temporary storage to check
// its CRC and store the results, then discard this temporary
// storage, since we don't use it in any but recovery operations
if (myDisk.Seek(header->partitionEntriesLBA)) {
partsToCheck = new GPTPart[header->numParts];
sizeOfParts = header->numParts * header->sizeOfPartitionEntries;
if (partsToCheck == NULL) {
cerr << "Could not allocate memory in GPTData::CheckTable()! Terminating!\n";
exit(1);
} // if
if (myDisk.Read(partsToCheck, sizeOfParts) != (int) sizeOfParts) {
cerr << "Warning! Error " << errno << " reading partition table for CRC check!\n";
} else {
newCRC = chksum_crc32((unsigned char*) partsToCheck, sizeOfParts);
allOK = (newCRC == header->partitionEntriesCRC);
if (header == &mainHeader)
otherHeader = &secondHeader;
else
otherHeader = &mainHeader;
if (newCRC != otherHeader->partitionEntriesCRC) {
cerr << "Warning! Main and backup partition tables differ! Use the 'c' and 'e' options\n"
<< "on the recovery & transformation menu to examine the two tables.\n\n";
allOK = 0;
} // if
} // if/else
delete[] partsToCheck;
} // if
return allOK;
} // GPTData::CheckTable()
// Writes GPT (and protective MBR) to disk. If quiet==1, moves the second
// header later on the disk without asking for permission, if necessary, and
// doesn't confirm the operation before writing. If quiet==0, asks permission
// before moving the second header and asks for final confirmation of any
// write.
// Returns 1 on successful write, 0 if there was a problem.
int GPTData::SaveGPTData(int quiet) {
int allOK = 1, syncIt = 1;
char answer;
// First do some final sanity checks....
// This test should only fail on read-only disks....
if (justLooking) {
cout << "The justLooking flag is set. This probably means you can't write to the disk.\n";
allOK = 0;
} // if
// Check that disk is really big enough to handle the second header...
if (mainHeader.backupLBA >= diskSize) {
cerr << "Caution! Secondary header was placed beyond the disk's limits! Moving the\n"
<< "header, but other problems may occur!\n";
MoveSecondHeaderToEnd();
} // if
// Is there enough space to hold the GPT headers and partition tables,
// given the partition sizes?
if (CheckGPTSize() > 0) {
allOK = 0;
} // if
// Check that second header is properly placed. Warn and ask if this should
// be corrected if the test fails....
if (mainHeader.backupLBA < (diskSize - UINT64_C(1))) {
if (quiet == 0) {
cout << "Warning! Secondary header is placed too early on the disk! Do you want to\n"
<< "correct this problem? ";
if (GetYN() == 'Y') {
MoveSecondHeaderToEnd();
cout << "Have moved second header and partition table to correct location.\n";
} else {
cout << "Have not corrected the problem. Strange problems may occur in the future!\n";
} // if correction requested
} else { // Go ahead and do correction automatically
MoveSecondHeaderToEnd();
} // if/else quiet
} // if
if ((mainHeader.lastUsableLBA >= diskSize) || (mainHeader.lastUsableLBA > mainHeader.backupLBA)) {
if (quiet == 0) {
cout << "Warning! The claimed last usable sector is incorrect! Do you want to correct\n"
<< "this problem? ";
if (GetYN() == 'Y') {
MoveSecondHeaderToEnd();
cout << "Have adjusted the second header and last usable sector value.\n";
} else {
cout << "Have not corrected the problem. Strange problems may occur in the future!\n";
} // if correction requested
} else { // go ahead and do correction automatically
MoveSecondHeaderToEnd();
} // if/else quiet
} // if
// Check for overlapping or insane partitions....
if ((FindOverlaps() > 0) || (FindInsanePartitions() > 0)) {
allOK = 0;
cerr << "Aborting write operation!\n";
} // if
// Check that protective MBR fits, and warn if it doesn't....
if (!protectiveMBR.DoTheyFit()) {
cerr << "\nPartition(s) in the protective MBR are too big for the disk! Creating a\n"
<< "fresh protective or hybrid MBR is recommended.\n";
}
// Check for mismatched MBR and GPT data, but let it pass if found
// (function displays warning message)
FindHybridMismatches();
RecomputeCRCs();
if ((allOK) && (!quiet)) {
cout << "\nFinal checks complete. About to write GPT data. THIS WILL OVERWRITE EXISTING\n"
<< "PARTITIONS!!\n\nDo you want to proceed? ";
answer = GetYN();
if (answer == 'Y') {
cout << "OK; writing new GUID partition table (GPT) to " << myDisk.GetName() << ".\n";
} else {
allOK = 0;
} // if/else
} // if
// Do it!
if (allOK) {
if (myDisk.OpenForWrite()) {
// As per UEFI specs, write the secondary table and GPT first....
allOK = SavePartitionTable(myDisk, secondHeader.partitionEntriesLBA);
if (!allOK) {
cerr << "Unable to save backup partition table! Perhaps the 'e' option on the experts'\n"
<< "menu will resolve this problem.\n";
syncIt = 0;
} // if
// Now write the secondary GPT header...
allOK = allOK && SaveHeader(&secondHeader, myDisk, mainHeader.backupLBA);
// Now write the main partition tables...
allOK = allOK && SavePartitionTable(myDisk, mainHeader.partitionEntriesLBA);
// Now write the main GPT header...
allOK = allOK && SaveHeader(&mainHeader, myDisk, 1);
// To top it off, write the protective MBR...
allOK = allOK && protectiveMBR.WriteMBRData(&myDisk);
// re-read the partition table
// Note: Done even if some write operations failed, but not if all of them failed.
// Done this way because I've received one problem report from a user one whose
// system the MBR write failed but everything else was OK (on a GPT disk under
// Windows), and the failure to sync therefore caused Windows to restore the
// original partition table from its cache. OTOH, such restoration might be
// desirable if the error occurs later; but that seems unlikely unless the initial
// write fails....
if (syncIt)
myDisk.DiskSync();
if (allOK) { // writes completed OK
cout << "The operation has completed successfully.\n";
} else {
cerr << "Warning! An error was reported when writing the partition table! This error\n"
<< "MIGHT be harmless, or the disk might be damaged! Checking it is advisable.\n";
} // if/else
myDisk.Close();
} else {
cerr << "Unable to open device '" << myDisk.GetName() << "' for writing! Errno is "
<< errno << "! Aborting write!\n";
allOK = 0;
} // if/else
} else {
cout << "Aborting write of new partition table.\n";
} // if
return (allOK);
} // GPTData::SaveGPTData()
// Save GPT data to a backup file. This function does much less error
// checking than SaveGPTData(). It can therefore preserve many types of
// corruption for later analysis; however, it preserves only the MBR,
// the main GPT header, the backup GPT header, and the main partition
// table; it discards the backup partition table, since it should be
// identical to the main partition table on healthy disks.
int GPTData::SaveGPTBackup(const string & filename) {
int allOK = 1;
DiskIO backupFile;
if (backupFile.OpenForWrite(filename)) {
// Recomputing the CRCs is likely to alter them, which could be bad
// if the intent is to save a potentially bad GPT for later analysis;
// but if we don't do this, we get bogus errors when we load the
// backup. I'm favoring misses over false alarms....
RecomputeCRCs();
protectiveMBR.WriteMBRData(&backupFile);
protectiveMBR.SetDisk(&myDisk);
if (allOK) {
// MBR write closed disk, so re-open and seek to end....
backupFile.OpenForWrite();
allOK = SaveHeader(&mainHeader, backupFile, 1);
} // if (allOK)
if (allOK)
allOK = SaveHeader(&secondHeader, backupFile, 2);
if (allOK)
allOK = SavePartitionTable(backupFile, 3);
if (allOK) { // writes completed OK
cout << "The operation has completed successfully.\n";
} else {
cerr << "Warning! An error was reported when writing the backup file.\n"
<< "It may not be usable!\n";
} // if/else
backupFile.Close();
} else {
cerr << "Unable to open file '" << filename << "' for writing! Aborting!\n";
allOK = 0;
} // if/else
return allOK;
} // GPTData::SaveGPTBackup()
// Write a GPT header (main or backup) to the specified sector. Used by both
// the SaveGPTData() and SaveGPTBackup() functions.
// Should be passed an architecture-appropriate header (DO NOT call
// ReverseHeaderBytes() on the header before calling this function)
// Returns 1 on success, 0 on failure
int GPTData::SaveHeader(struct GPTHeader *header, DiskIO & disk, uint64_t sector) {
int littleEndian, allOK = 1;
littleEndian = IsLittleEndian();
if (!littleEndian)
ReverseHeaderBytes(header);
if (disk.Seek(sector)) {
if (disk.Write(header, 512) == -1)
allOK = 0;
} else allOK = 0; // if (disk.Seek()...)
if (!littleEndian)
ReverseHeaderBytes(header);
return allOK;
} // GPTData::SaveHeader()
// Save the partitions to the specified sector. Used by both the SaveGPTData()
// and SaveGPTBackup() functions.
// Should be passed an architecture-appropriate header (DO NOT call
// ReverseHeaderBytes() on the header before calling this function)
// Returns 1 on success, 0 on failure
int GPTData::SavePartitionTable(DiskIO & disk, uint64_t sector) {
int littleEndian, allOK = 1;
littleEndian = IsLittleEndian();
if (disk.Seek(sector)) {
if (!littleEndian)
ReversePartitionBytes();
if (disk.Write(partitions, mainHeader.sizeOfPartitionEntries * numParts) == -1)
allOK = 0;
if (!littleEndian)
ReversePartitionBytes();
} else allOK = 0; // if (myDisk.Seek()...)
return allOK;
} // GPTData::SavePartitionTable()
// Load GPT data from a backup file created by SaveGPTBackup(). This function
// does minimal error checking. It returns 1 if it completed successfully,
// 0 if there was a problem. In the latter case, it creates a new empty
// set of partitions.
int GPTData::LoadGPTBackup(const string & filename) {
int allOK = 1, val, err;
int shortBackup = 0;
DiskIO backupFile;
if (backupFile.OpenForRead(filename)) {
// Let the MBRData class load the saved MBR...
protectiveMBR.ReadMBRData(&backupFile, 0); // 0 = don't check block size
protectiveMBR.SetDisk(&myDisk);
LoadHeader(&mainHeader, backupFile, 1, &mainCrcOk);
// Check backup file size and rebuild second header if file is right
// size to be direct dd copy of MBR, main header, and main partition
// table; if other size, treat it like a GPT fdisk-generated backup
// file
shortBackup = ((backupFile.DiskSize(&err) * backupFile.GetBlockSize()) ==
(mainHeader.numParts * mainHeader.sizeOfPartitionEntries) + 1024);
if (shortBackup) {
RebuildSecondHeader();
secondCrcOk = mainCrcOk;
} else {
LoadHeader(&secondHeader, backupFile, 2, &secondCrcOk);
} // if/else
// Return valid headers code: 0 = both headers bad; 1 = main header
// good, backup bad; 2 = backup header good, main header bad;
// 3 = both headers good. Note these codes refer to valid GPT
// signatures and version numbers; more subtle problems will elude
// this check!
if ((val = CheckHeaderValidity()) > 0) {
if (val == 2) { // only backup header seems to be good
SetGPTSize(secondHeader.numParts, 0);
} else { // main header is OK
SetGPTSize(mainHeader.numParts, 0);
} // if/else
if (secondHeader.currentLBA != diskSize - UINT64_C(1)) {
cout << "Warning! Current disk size doesn't match that of the backup!\n"
<< "Adjusting sizes to match, but subsequent problems are possible!\n";
MoveSecondHeaderToEnd();
} // if
if (!LoadPartitionTable(mainHeader, backupFile, (uint64_t) (3 - shortBackup)))
cerr << "Warning! Read error " << errno
<< " loading partition table; strange behavior now likely!\n";
} else {
allOK = 0;
} // if/else
// Something went badly wrong, so blank out partitions
if (allOK == 0) {
cerr << "Improper backup file! Clearing all partition data!\n";
ClearGPTData();
protectiveMBR.MakeProtectiveMBR();
} // if
} else {
allOK = 0;
cerr << "Unable to open file '" << filename << "' for reading! Aborting!\n";
} // if/else
return allOK;
} // GPTData::LoadGPTBackup()
int GPTData::SaveMBR(void) {
return protectiveMBR.WriteMBRData(&myDisk);
} // GPTData::SaveMBR()
// This function destroys the on-disk GPT structures, but NOT the on-disk
// MBR.
// Returns 1 if the operation succeeds, 0 if not.
int GPTData::DestroyGPT(void) {
int sum, tableSize, allOK = 1;
uint8_t blankSector[512];
uint8_t* emptyTable;
memset(blankSector, 0, sizeof(blankSector));
ClearGPTData();
if (myDisk.OpenForWrite()) {
if (!myDisk.Seek(mainHeader.currentLBA))
allOK = 0;
if (myDisk.Write(blankSector, 512) != 512) { // blank it out
cerr << "Warning! GPT main header not overwritten! Error is " << errno << "\n";
allOK = 0;
} // if
if (!myDisk.Seek(mainHeader.partitionEntriesLBA))
allOK = 0;
tableSize = numParts * mainHeader.sizeOfPartitionEntries;
emptyTable = new uint8_t[tableSize];
if (emptyTable == NULL) {
cerr << "Could not allocate memory in GPTData::DestroyGPT()! Terminating!\n";
exit(1);
} // if
memset(emptyTable, 0, tableSize);
if (allOK) {
sum = myDisk.Write(emptyTable, tableSize);
if (sum != tableSize) {
cerr << "Warning! GPT main partition table not overwritten! Error is " << errno << "\n";
allOK = 0;
} // if write failed
} // if
if (!myDisk.Seek(secondHeader.partitionEntriesLBA))
allOK = 0;
if (allOK) {
sum = myDisk.Write(emptyTable, tableSize);
if (sum != tableSize) {
cerr << "Warning! GPT backup partition table not overwritten! Error is "
<< errno << "\n";
allOK = 0;
} // if wrong size written
} // if
if (!myDisk.Seek(secondHeader.currentLBA))
allOK = 0;
if (allOK) {
if (myDisk.Write(blankSector, 512) != 512) { // blank it out
cerr << "Warning! GPT backup header not overwritten! Error is " << errno << "\n";
allOK = 0;
} // if
} // if
myDisk.DiskSync();
myDisk.Close();
cout << "GPT data structures destroyed! You may now partition the disk using fdisk or\n"
<< "other utilities.\n";
delete[] emptyTable;
} else {
cerr << "Problem opening '" << device << "' for writing! Program will now terminate.\n";
} // if/else (fd != -1)
return (allOK);
} // GPTDataTextUI::DestroyGPT()
// Wipe MBR data from the disk (zero it out completely)
// Returns 1 on success, 0 on failure.
int GPTData::DestroyMBR(void) {
int allOK;
uint8_t blankSector[512];
memset(blankSector, 0, sizeof(blankSector));
allOK = myDisk.OpenForWrite() && myDisk.Seek(0) && (myDisk.Write(blankSector, 512) == 512);
if (!allOK)
cerr << "Warning! MBR not overwritten! Error is " << errno << "!\n";
return allOK;
} // GPTData::DestroyMBR(void)
// Tell user whether Apple Partition Map (APM) was discovered....
void GPTData::ShowAPMState(void) {
if (apmFound)
cout << " APM: present\n";
else
cout << " APM: not present\n";
} // GPTData::ShowAPMState()
// Tell user about the state of the GPT data....
void GPTData::ShowGPTState(void) {
switch (state) {
case gpt_invalid:
cout << " GPT: not present\n";
break;
case gpt_valid:
cout << " GPT: present\n";
break;
case gpt_corrupt:
cout << " GPT: damaged\n";
break;
default:
cout << "\a GPT: unknown -- bug!\n";
break;
} // switch
} // GPTData::ShowGPTState()
// Display the basic GPT data
void GPTData::DisplayGPTData(void) {
uint32_t i;
uint64_t temp, totalFree;
cout << "Disk " << device << ": " << diskSize << " sectors, "
<< BytesToIeee(diskSize, blockSize) << "\n";
cout << "Logical sector size: " << blockSize << " bytes\n";
cout << "Disk identifier (GUID): " << mainHeader.diskGUID << "\n";
cout << "Partition table holds up to " << numParts << " entries\n";
cout << "First usable sector is " << mainHeader.firstUsableLBA
<< ", last usable sector is " << mainHeader.lastUsableLBA << "\n";
totalFree = FindFreeBlocks(&i, &temp);
cout << "Partitions will be aligned on " << sectorAlignment << "-sector boundaries\n";
cout << "Total free space is " << totalFree << " sectors ("
<< BytesToIeee(totalFree, blockSize) << ")\n";
cout << "\nNumber Start (sector) End (sector) Size Code Name\n";
for (i = 0; i < numParts; i++) {
partitions[i].ShowSummary(i, blockSize);
} // for
} // GPTData::DisplayGPTData()
// Show detailed information on the specified partition
void GPTData::ShowPartDetails(uint32_t partNum) {
if ((partNum < numParts) && !IsFreePartNum(partNum)) {
partitions[partNum].ShowDetails(blockSize);
} else {
cout << "Partition #" << partNum + 1 << " does not exist.\n";
} // if
} // GPTData::ShowPartDetails()
/**************************************************************************
* *
* Partition table transformation functions (MBR or BSD disklabel to GPT) *
* (some of these functions may require user interaction) *
* *
**************************************************************************/
// Examines the MBR & GPT data to determine which set of data to use: the
// MBR (use_mbr), the GPT (use_gpt), the BSD disklabel (use_bsd), or create
// a new set of partitions (use_new). A return value of use_abort indicates
// that this function couldn't determine what to do. Overriding functions
// in derived classes may ask users questions in such cases.
WhichToUse GPTData::UseWhichPartitions(void) {
WhichToUse which = use_new;
MBRValidity mbrState;
mbrState = protectiveMBR.GetValidity();
if ((state == gpt_invalid) && ((mbrState == mbr) || (mbrState == hybrid))) {
cout << "\n***************************************************************\n"
<< "Found invalid GPT and valid MBR; converting MBR to GPT format\n"
<< "in memory. ";
if (!justLooking) {
cout << "\aTHIS OPERATION IS POTENTIALLY DESTRUCTIVE! Exit by\n"
<< "typing 'q' if you don't want to convert your MBR partitions\n"
<< "to GPT format!";
} // if
cout << "\n***************************************************************\n\n";
which = use_mbr;
} // if
if ((state == gpt_invalid) && bsdFound) {
cout << "\n**********************************************************************\n"
<< "Found invalid GPT and valid BSD disklabel; converting BSD disklabel\n"
<< "to GPT format.";
if ((!justLooking) && (!beQuiet)) {
cout << "\a THIS OPERATION IS POTENTIALLY DESTRUCTIVE! Your first\n"
<< "BSD partition will likely be unusable. Exit by typing 'q' if you don't\n"
<< "want to convert your BSD partitions to GPT format!";
} // if
cout << "\n**********************************************************************\n\n";
which = use_bsd;
} // if
if ((state == gpt_valid) && (mbrState == gpt)) {
which = use_gpt;
if (!beQuiet)
cout << "Found valid GPT with protective MBR; using GPT.\n";
} // if
if ((state == gpt_valid) && (mbrState == hybrid)) {
which = use_gpt;
if (!beQuiet)
cout << "Found valid GPT with hybrid MBR; using GPT.\n";
} // if
if ((state == gpt_valid) && (mbrState == invalid)) {
cout << "\aFound valid GPT with corrupt MBR; using GPT and will write new\n"
<< "protective MBR on save.\n";
which = use_gpt;
} // if
if ((state == gpt_valid) && (mbrState == mbr)) {
which = use_abort;
} // if
if (state == gpt_corrupt) {
if (mbrState == gpt) {
cout << "\a\a****************************************************************************\n"
<< "Caution: Found protective or hybrid MBR and corrupt GPT. Using GPT, but disk\n"
<< "verification and recovery are STRONGLY recommended.\n"
<< "****************************************************************************\n";
which = use_gpt;
} else {
which = use_abort;
} // if/else MBR says disk is GPT
} // if GPT corrupt
if (which == use_new)
cout << "Creating new GPT entries.\n";
return which;
} // UseWhichPartitions()
// Convert MBR partition table into GPT form.
void GPTData::XFormPartitions(void) {
int i, numToConvert;
uint8_t origType;
// Clear out old data & prepare basics....
ClearGPTData();
// Convert the smaller of the # of GPT or MBR partitions
if (numParts > MAX_MBR_PARTS)
numToConvert = MAX_MBR_PARTS;
else
numToConvert = numParts;
for (i = 0; i < numToConvert; i++) {
origType = protectiveMBR.GetType(i);
// don't waste CPU time trying to convert extended, hybrid protective, or
// null (non-existent) partitions
if ((origType != 0x05) && (origType != 0x0f) && (origType != 0x85) &&
(origType != 0x00) && (origType != 0xEE))
partitions[i] = protectiveMBR.AsGPT(i);
} // for
// Convert MBR into protective MBR
protectiveMBR.MakeProtectiveMBR();
// Record that all original CRCs were OK so as not to raise flags
// when doing a disk verification
mainCrcOk = secondCrcOk = mainPartsCrcOk = secondPartsCrcOk = 1;
} // GPTData::XFormPartitions()
// Transforms BSD disklabel on the specified partition (numbered from 0).
// If an invalid partition number is given, the program does nothing.
// Returns the number of new partitions created.
int GPTData::XFormDisklabel(uint32_t partNum) {
uint32_t low, high;
int goOn = 1, numDone = 0;
BSDData disklabel;
if (GetPartRange(&low, &high) == 0) {
goOn = 0;
cout << "No partitions!\n";
} // if
if (partNum > high) {
goOn = 0;
cout << "Specified partition is invalid!\n";
} // if
// If all is OK, read the disklabel and convert it.
if (goOn) {
goOn = disklabel.ReadBSDData(&myDisk, partitions[partNum].GetFirstLBA(),
partitions[partNum].GetLastLBA());
if ((goOn) && (disklabel.IsDisklabel())) {
numDone = XFormDisklabel(&disklabel);
if (numDone == 1)
cout << "Converted 1 BSD partition.\n";
else
cout << "Converted " << numDone << " BSD partitions.\n";
} else {
cout << "Unable to convert partitions! Unrecognized BSD disklabel.\n";
} // if/else
} // if
if (numDone > 0) { // converted partitions; delete carrier
partitions[partNum].BlankPartition();
} // if
return numDone;
} // GPTData::XFormDisklabel(uint32_t i)
// Transform the partitions on an already-loaded BSD disklabel...
int GPTData::XFormDisklabel(BSDData* disklabel) {
int i, partNum = 0, numDone = 0;
if (disklabel->IsDisklabel()) {
for (i = 0; i < disklabel->GetNumParts(); i++) {
partNum = FindFirstFreePart();
if (partNum >= 0) {
partitions[partNum] = disklabel->AsGPT(i);
if (partitions[partNum].IsUsed())
numDone++;
} // if
} // for
if (partNum == -1)
cerr << "Warning! Too many partitions to convert!\n";
} // if
// Record that all original CRCs were OK so as not to raise flags
// when doing a disk verification
mainCrcOk = secondCrcOk = mainPartsCrcOk = secondPartsCrcOk = 1;
return numDone;
} // GPTData::XFormDisklabel(BSDData* disklabel)
// Add one GPT partition to MBR. Used by PartsToMBR() functions. Created
// partition has the active/bootable flag UNset and uses the GPT fdisk
// type code divided by 0x0100 as the MBR type code.
// Returns 1 if operation was 100% successful, 0 if there were ANY
// problems.
int GPTData::OnePartToMBR(uint32_t gptPart, int mbrPart) {
int allOK = 1;
if ((mbrPart < 0) || (mbrPart > 3)) {
cout << "MBR partition " << mbrPart + 1 << " is out of range; omitting it.\n";
allOK = 0;
} // if
if (gptPart >= numParts) {
cout << "GPT partition " << gptPart + 1 << " is out of range; omitting it.\n";
allOK = 0;
} // if
if (allOK && (partitions[gptPart].GetLastLBA() == UINT64_C(0))) {
cout << "GPT partition " << gptPart + 1 << " is undefined; omitting it.\n";
allOK = 0;
} // if
if (allOK && (partitions[gptPart].GetFirstLBA() <= UINT32_MAX) &&
(partitions[gptPart].GetLengthLBA() <= UINT32_MAX)) {
if (partitions[gptPart].GetLastLBA() > UINT32_MAX) {
cout << "Caution: Partition end point past 32-bit pointer boundary;"
<< " some OSes may\nreact strangely.\n";
} // if
protectiveMBR.MakePart(mbrPart, (uint32_t) partitions[gptPart].GetFirstLBA(),
(uint32_t) partitions[gptPart].GetLengthLBA(),
partitions[gptPart].GetHexType() / 256, 0);
} else { // partition out of range
if (allOK) // Display only if "else" triggered by out-of-bounds condition
cout << "Partition " << gptPart + 1 << " begins beyond the 32-bit pointer limit of MBR "
<< "partitions, or is\n too big; omitting it.\n";
allOK = 0;
} // if/else
return allOK;
} // GPTData::OnePartToMBR()
/**********************************************************************
* *
* Functions that adjust GPT data structures WITHOUT user interaction *
* (they may display information for the user's benefit, though) *
* *
**********************************************************************/
// Resizes GPT to specified number of entries. Creates a new table if
// necessary, copies data if it already exists. If fillGPTSectors is 1
// (the default), rounds numEntries to fill all the sectors necessary to
// hold the GPT.
// Returns 1 if all goes well, 0 if an error is encountered.
int GPTData::SetGPTSize(uint32_t numEntries, int fillGPTSectors) {
GPTPart* newParts;
uint32_t i, high, copyNum, entriesPerSector;
int allOK = 1;
// First, adjust numEntries upward, if necessary, to get a number
// that fills the allocated sectors
entriesPerSector = blockSize / GPT_SIZE;
if (fillGPTSectors && ((numEntries % entriesPerSector) != 0)) {
cout << "Adjusting GPT size from " << numEntries << " to ";
numEntries = ((numEntries / entriesPerSector) + 1) * entriesPerSector;
cout << numEntries << " to fill the sector\n";
} // if
// Do the work only if the # of partitions is changing. Along with being
// efficient, this prevents mucking with the location of the secondary
// partition table, which causes problems when loading data from a RAID
// array that's been expanded because this function is called when loading
// data.
if (((numEntries != numParts) || (partitions == NULL)) && (numEntries > 0)) {
newParts = new GPTPart [numEntries];
if (newParts != NULL) {
if (partitions != NULL) { // existing partitions; copy them over
GetPartRange(&i, &high);
if (numEntries < (high + 1)) { // Highest entry too high for new #
cout << "The highest-numbered partition is " << high + 1
<< ", which is greater than the requested\n"
<< "partition table size of " << numEntries
<< "; cannot resize. Perhaps sorting will help.\n";
allOK = 0;
delete[] newParts;
} else { // go ahead with copy
if (numEntries < numParts)
copyNum = numEntries;
else
copyNum = numParts;
for (i = 0; i < copyNum; i++) {
newParts[i] = partitions[i];
} // for
delete[] partitions;
partitions = newParts;
} // if
} else { // No existing partition table; just create it
partitions = newParts;
} // if/else existing partitions
numParts = numEntries;
mainHeader.firstUsableLBA = ((numEntries * GPT_SIZE) / blockSize) + (((numEntries * GPT_SIZE) % blockSize) != 0) + 2 ;
secondHeader.firstUsableLBA = mainHeader.firstUsableLBA;
MoveSecondHeaderToEnd();
if (diskSize > 0)
CheckGPTSize();
} else { // Bad memory allocation
cerr << "Error allocating memory for partition table! Size is unchanged!\n";
allOK = 0;
} // if/else
} // if/else
mainHeader.numParts = numParts;
secondHeader.numParts = numParts;
return (allOK);
} // GPTData::SetGPTSize()
// Blank the partition array
void GPTData::BlankPartitions(void) {
uint32_t i;
for (i = 0; i < numParts; i++) {
partitions[i].BlankPartition();
} // for
} // GPTData::BlankPartitions()
// Delete a partition by number. Returns 1 if successful,
// 0 if there was a problem. Returns 1 if partition was in
// range, 0 if it was out of range.
int GPTData::DeletePartition(uint32_t partNum) {
uint64_t startSector, length;
uint32_t low, high, numUsedParts, retval = 1;;
numUsedParts = GetPartRange(&low, &high);
if ((numUsedParts > 0) && (partNum >= low) && (partNum <= high)) {
// In case there's a protective MBR, look for & delete matching
// MBR partition....
startSector = partitions[partNum].GetFirstLBA();
length = partitions[partNum].GetLengthLBA();
protectiveMBR.DeleteByLocation(startSector, length);
// Now delete the GPT partition
partitions[partNum].BlankPartition();
} else {
cerr << "Partition number " << partNum + 1 << " out of range!\n";
retval = 0;
} // if/else
return retval;
} // GPTData::DeletePartition(uint32_t partNum)
// Non-interactively create a partition.
// Returns 1 if the operation was successful, 0 if a problem was discovered.
uint32_t GPTData::CreatePartition(uint32_t partNum, uint64_t startSector, uint64_t endSector) {
int retval = 1; // assume there'll be no problems
uint64_t origSector = startSector;
if (IsFreePartNum(partNum)) {
if (Align(&startSector)) {
cout << "Information: Moved requested sector from " << origSector << " to "
<< startSector << " in\norder to align on " << sectorAlignment
<< "-sector boundaries.\n";
} // if
if (IsFree(startSector) && (startSector <= endSector)) {
if (FindLastInFree(startSector) >= endSector) {
partitions[partNum].SetFirstLBA(startSector);
partitions[partNum].SetLastLBA(endSector);
partitions[partNum].SetType(DEFAULT_GPT_TYPE);
partitions[partNum].RandomizeUniqueGUID();
} else retval = 0; // if free space until endSector
} else retval = 0; // if startSector is free
} else retval = 0; // if legal partition number
return retval;
} // GPTData::CreatePartition(partNum, startSector, endSector)
// Sort the GPT entries, eliminating gaps and making for a logical
// ordering.
void GPTData::SortGPT(void) {
if (numParts > 0)
sort(partitions, partitions + numParts);
} // GPTData::SortGPT()
// Swap the contents of two partitions.
// Returns 1 if successful, 0 if either partition is out of range
// (that is, not a legal number; either or both can be empty).
// Note that if partNum1 = partNum2 and this number is in range,
// it will be considered successful.
int GPTData::SwapPartitions(uint32_t partNum1, uint32_t partNum2) {
GPTPart temp;
int allOK = 1;
if ((partNum1 < numParts) && (partNum2 < numParts)) {
if (partNum1 != partNum2) {
temp = partitions[partNum1];
partitions[partNum1] = partitions[partNum2];
partitions[partNum2] = temp;
} // if
} else allOK = 0; // partition numbers are valid
return allOK;
} // GPTData::SwapPartitions()
// Set up data structures for entirely new set of partitions on the
// specified device. Returns 1 if OK, 0 if there were problems.
// Note that this function does NOT clear the protectiveMBR data
// structure, since it may hold the original MBR partitions if the
// program was launched on an MBR disk, and those may need to be
// converted to GPT format.
int GPTData::ClearGPTData(void) {
int goOn = 1, i;
// Set up the partition table....
delete[] partitions;
partitions = NULL;
SetGPTSize(NUM_GPT_ENTRIES);
// Now initialize a bunch of stuff that's static....
mainHeader.signature = GPT_SIGNATURE;
mainHeader.revision = 0x00010000;
mainHeader.headerSize = HEADER_SIZE;
mainHeader.reserved = 0;
mainHeader.currentLBA = UINT64_C(1);
mainHeader.partitionEntriesLBA = (uint64_t) 2;
mainHeader.sizeOfPartitionEntries = GPT_SIZE;
for (i = 0; i < GPT_RESERVED; i++) {
mainHeader.reserved2[i] = '\0';
} // for
if (blockSize > 0)
sectorAlignment = DEFAULT_ALIGNMENT * SECTOR_SIZE / blockSize;
else
sectorAlignment = DEFAULT_ALIGNMENT;
// Now some semi-static items (computed based on end of disk)
mainHeader.backupLBA = diskSize - UINT64_C(1);
mainHeader.lastUsableLBA = diskSize - mainHeader.firstUsableLBA;
// Set a unique GUID for the disk, based on random numbers
mainHeader.diskGUID.Randomize();
// Copy main header to backup header
RebuildSecondHeader();
// Blank out the partitions array....
BlankPartitions();
// Flag all CRCs as being OK....
mainCrcOk = 1;
secondCrcOk = 1;
mainPartsCrcOk = 1;
secondPartsCrcOk = 1;
return (goOn);
} // GPTData::ClearGPTData()
// Set the location of the second GPT header data to the end of the disk.
// If the disk size has actually changed, this also adjusts the protective
// entry in the MBR, since it's probably no longer correct.
// Used internally and called by the 'e' option on the recovery &
// transformation menu, to help users of RAID arrays who add disk space
// to their arrays or to adjust data structures in restore operations
// involving unequal-sized disks.
void GPTData::MoveSecondHeaderToEnd() {
mainHeader.backupLBA = secondHeader.currentLBA = diskSize - UINT64_C(1);
if (mainHeader.lastUsableLBA != diskSize - mainHeader.firstUsableLBA) {
if (protectiveMBR.GetValidity() == hybrid) {
protectiveMBR.OptimizeEESize();
RecomputeCHS();
} // if
if (protectiveMBR.GetValidity() == gpt)
MakeProtectiveMBR();
} // if
mainHeader.lastUsableLBA = secondHeader.lastUsableLBA = diskSize - mainHeader.firstUsableLBA;
secondHeader.partitionEntriesLBA = secondHeader.lastUsableLBA + UINT64_C(1);
} // GPTData::FixSecondHeaderLocation()
// Sets the partition's name to the specified UnicodeString without
// user interaction.
// Returns 1 on success, 0 on failure (invalid partition number).
int GPTData::SetName(uint32_t partNum, const UnicodeString & theName) {
int retval = 1;
if (IsUsedPartNum(partNum))
partitions[partNum].SetName(theName);
else
retval = 0;
return retval;
} // GPTData::SetName
// Set the disk GUID to the specified value. Note that the header CRCs must
// be recomputed after calling this function.
void GPTData::SetDiskGUID(GUIDData newGUID) {
mainHeader.diskGUID = newGUID;
secondHeader.diskGUID = newGUID;
} // SetDiskGUID()
// Set the unique GUID of the specified partition. Returns 1 on
// successful completion, 0 if there were problems (invalid
// partition number).
int GPTData::SetPartitionGUID(uint32_t pn, GUIDData theGUID) {
int retval = 0;
if (pn < numParts) {
if (partitions[pn].IsUsed()) {
partitions[pn].SetUniqueGUID(theGUID);
retval = 1;
} // if
} // if
return retval;
} // GPTData::SetPartitionGUID()
// Set new random GUIDs for the disk and all partitions. Intended to be used
// after disk cloning or similar operations that don't randomize the GUIDs.
void GPTData::RandomizeGUIDs(void) {
uint32_t i;
mainHeader.diskGUID.Randomize();
secondHeader.diskGUID = mainHeader.diskGUID;
for (i = 0; i < numParts; i++)
if (partitions[i].IsUsed())
partitions[i].RandomizeUniqueGUID();
} // GPTData::RandomizeGUIDs()
// Change partition type code non-interactively. Returns 1 if
// successful, 0 if not....
int GPTData::ChangePartType(uint32_t partNum, PartType theGUID) {
int retval = 1;
if (!IsFreePartNum(partNum)) {
partitions[partNum].SetType(theGUID);
} else retval = 0;
return retval;
} // GPTData::ChangePartType()
// Recompute the CHS values of all the MBR partitions. Used to reset
// CHS values that some BIOSes require, despite the fact that the
// resulting CHS values violate the GPT standard.
void GPTData::RecomputeCHS(void) {
int i;
for (i = 0; i < 4; i++)
protectiveMBR.RecomputeCHS(i);
} // GPTData::RecomputeCHS()
// Adjust sector number so that it falls on a sector boundary that's a
// multiple of sectorAlignment. This is done to improve the performance
// of Western Digital Advanced Format disks and disks with similar
// technology from other companies, which use 4096-byte sectors
// internally although they translate to 512-byte sectors for the
// benefit of the OS. If partitions aren't properly aligned on these
// disks, some filesystem data structures can span multiple physical
// sectors, degrading performance. This function should be called
// only on the FIRST sector of the partition, not the last!
// This function returns 1 if the alignment was altered, 0 if it
// was unchanged.
int GPTData::Align(uint64_t* sector) {
int retval = 0, sectorOK = 0;
uint64_t earlier, later, testSector;
if ((*sector % sectorAlignment) != 0) {
earlier = (*sector / sectorAlignment) * sectorAlignment;
later = earlier + (uint64_t) sectorAlignment;
// Check to see that every sector between the earlier one and the
// requested one is clear, and that it's not too early....
if (earlier >= mainHeader.firstUsableLBA) {
sectorOK = 1;
testSector = earlier;
do {
sectorOK = IsFree(testSector++);
} while ((sectorOK == 1) && (testSector < *sector));
if (sectorOK == 1) {
*sector = earlier;
retval = 1;
} // if
} // if firstUsableLBA check
// If couldn't move the sector earlier, try to move it later instead....
if ((sectorOK != 1) && (later <= mainHeader.lastUsableLBA)) {
sectorOK = 1;
testSector = later;
do {
sectorOK = IsFree(testSector--);
} while ((sectorOK == 1) && (testSector > *sector));
if (sectorOK == 1) {
*sector = later;
retval = 1;
} // if
} // if
} // if
return retval;
} // GPTData::Align()
/********************************************************
* *
* Functions that return data about GPT data structures *
* (most of these are inline in gpt.h) *
* *
********************************************************/
// Find the low and high used partition numbers (numbered from 0).
// Return value is the number of partitions found. Note that the
// *low and *high values are both set to 0 when no partitions
// are found, as well as when a single partition in the first
// position exists. Thus, the return value is the only way to
// tell when no partitions exist.
int GPTData::GetPartRange(uint32_t *low, uint32_t *high) {
uint32_t i;
int numFound = 0;
*low = numParts + 1; // code for "not found"
*high = 0;
for (i = 0; i < numParts; i++) {
if (partitions[i].IsUsed()) { // it exists
*high = i; // since we're counting up, set the high value
// Set the low value only if it's not yet found...
if (*low == (numParts + 1)) *low = i;
numFound++;
} // if
} // for
// Above will leave *low pointing to its "not found" value if no partitions
// are defined, so reset to 0 if this is the case....
if (*low == (numParts + 1))
*low = 0;
return numFound;
} // GPTData::GetPartRange()
// Returns the value of the first free partition, or -1 if none is
// unused.
int GPTData::FindFirstFreePart(void) {
int i = 0;
if (partitions != NULL) {
while ((i < (int) numParts) && (partitions[i].IsUsed()))
i++;
if (i >= (int) numParts)
i = -1;
} else i = -1;
return i;
} // GPTData::FindFirstFreePart()
// Returns the number of defined partitions.
uint32_t GPTData::CountParts(void) {
uint32_t i, counted = 0;
for (i = 0; i < numParts; i++) {
if (partitions[i].IsUsed())
counted++;
} // for
return counted;
} // GPTData::CountParts()
/****************************************************
* *
* Functions that return data about disk free space *
* *
****************************************************/
// Find the first available block after the starting point; returns 0 if
// there are no available blocks left
uint64_t GPTData::FindFirstAvailable(uint64_t start) {
uint64_t first;
uint32_t i;
int firstMoved = 0;
// Begin from the specified starting point or from the first usable
// LBA, whichever is greater...
if (start < mainHeader.firstUsableLBA)
first = mainHeader.firstUsableLBA;
else
first = start;
// ...now search through all partitions; if first is within an
// existing partition, move it to the next sector after that
// partition and repeat. If first was moved, set firstMoved
// flag; repeat until firstMoved is not set, so as to catch
// cases where partitions are out of sequential order....
do {
firstMoved = 0;
for (i = 0; i < numParts; i++) {
if ((partitions[i].IsUsed()) && (first >= partitions[i].GetFirstLBA()) &&
(first <= partitions[i].GetLastLBA())) { // in existing part.
first = partitions[i].GetLastLBA() + 1;
firstMoved = 1;
} // if
} // for
} while (firstMoved == 1);
if (first > mainHeader.lastUsableLBA)
first = 0;
return (first);
} // GPTData::FindFirstAvailable()
// Finds the first available sector in the largest block of unallocated
// space on the disk. Returns 0 if there are no available blocks left
uint64_t GPTData::FindFirstInLargest(void) {
uint64_t start, firstBlock, lastBlock, segmentSize, selectedSize = 0, selectedSegment = 0;
start = 0;
do {
firstBlock = FindFirstAvailable(start);
if (firstBlock != UINT32_C(0)) { // something's free...
lastBlock = FindLastInFree(firstBlock);
segmentSize = lastBlock - firstBlock + UINT32_C(1);
if (segmentSize > selectedSize) {
selectedSize = segmentSize;
selectedSegment = firstBlock;
} // if
start = lastBlock + 1;
} // if
} while (firstBlock != 0);
return selectedSegment;
} // GPTData::FindFirstInLargest()
// Find the last available block on the disk.
// Returns 0 if there are no available sectors
uint64_t GPTData::FindLastAvailable(void) {
uint64_t last;
uint32_t i;
int lastMoved = 0;
// Start by assuming the last usable LBA is available....
last = mainHeader.lastUsableLBA;
// ...now, similar to algorithm in FindFirstAvailable(), search
// through all partitions, moving last when it's in an existing
// partition. Set the lastMoved flag so we repeat to catch cases
// where partitions are out of logical order.
do {
lastMoved = 0;
for (i = 0; i < numParts; i++) {
if ((last >= partitions[i].GetFirstLBA()) &&
(last <= partitions[i].GetLastLBA())) { // in existing part.
last = partitions[i].GetFirstLBA() - 1;
lastMoved = 1;
} // if
} // for
} while (lastMoved == 1);
if (last < mainHeader.firstUsableLBA)
last = 0;
return (last);
} // GPTData::FindLastAvailable()
// Find the last available block in the free space pointed to by start.
uint64_t GPTData::FindLastInFree(uint64_t start) {
uint64_t nearestStart;
uint32_t i;
nearestStart = mainHeader.lastUsableLBA;
for (i = 0; i < numParts; i++) {
if ((nearestStart > partitions[i].GetFirstLBA()) &&
(partitions[i].GetFirstLBA() > start)) {
nearestStart = partitions[i].GetFirstLBA() - 1;
} // if
} // for
return (nearestStart);
} // GPTData::FindLastInFree()
// Finds the total number of free blocks, the number of segments in which
// they reside, and the size of the largest of those segments
uint64_t GPTData::FindFreeBlocks(uint32_t *numSegments, uint64_t *largestSegment) {
uint64_t start = UINT64_C(0); // starting point for each search
uint64_t totalFound = UINT64_C(0); // running total
uint64_t firstBlock; // first block in a segment
uint64_t lastBlock; // last block in a segment
uint64_t segmentSize; // size of segment in blocks
uint32_t num = 0;
*largestSegment = UINT64_C(0);
if (diskSize > 0) {
do {
firstBlock = FindFirstAvailable(start);
if (firstBlock != UINT64_C(0)) { // something's free...
lastBlock = FindLastInFree(firstBlock);
segmentSize = lastBlock - firstBlock + UINT64_C(1);
if (segmentSize > *largestSegment) {
*largestSegment = segmentSize;
} // if
totalFound += segmentSize;
num++;
start = lastBlock + 1;
} // if
} while (firstBlock != 0);
} // if
*numSegments = num;
return totalFound;
} // GPTData::FindFreeBlocks()
// Returns 1 if sector is unallocated, 0 if it's allocated to a partition.
// If it's allocated, return the partition number to which it's allocated
// in partNum, if that variable is non-NULL. (A value of UINT32_MAX is
// returned in partNum if the sector is in use by basic GPT data structures.)
int GPTData::IsFree(uint64_t sector, uint32_t *partNum) {
int isFree = 1;
uint32_t i;
for (i = 0; i < numParts; i++) {
if ((sector >= partitions[i].GetFirstLBA()) &&
(sector <= partitions[i].GetLastLBA())) {
isFree = 0;
if (partNum != NULL)
*partNum = i;
} // if
} // for
if ((sector < mainHeader.firstUsableLBA) ||
(sector > mainHeader.lastUsableLBA)) {
isFree = 0;
if (partNum != NULL)
*partNum = UINT32_MAX;
} // if
return (isFree);
} // GPTData::IsFree()
// Returns 1 if partNum is unused AND if it's a legal value.
int GPTData::IsFreePartNum(uint32_t partNum) {
return ((partNum < numParts) && (partitions != NULL) &&
(!partitions[partNum].IsUsed()));
} // GPTData::IsFreePartNum()
// Returns 1 if partNum is in use.
int GPTData::IsUsedPartNum(uint32_t partNum) {
return ((partNum < numParts) && (partitions != NULL) &&
(partitions[partNum].IsUsed()));
} // GPTData::IsUsedPartNum()
/***********************************************************
* *
* Change how functions work or return information on them *
* *
***********************************************************/
// Set partition alignment value; partitions will begin on multiples of
// the specified value
void GPTData::SetAlignment(uint32_t n) {
if (n > 0)
sectorAlignment = n;
else
cerr << "Attempt to set partition alignment to 0!\n";
} // GPTData::SetAlignment()
// Compute sector alignment based on the current partitions (if any). Each
// partition's starting LBA is examined, and if it's divisible by a power-of-2
// value less than or equal to the DEFAULT_ALIGNMENT value (adjusted for the
// sector size), but not by the previously-located alignment value, then the
// alignment value is adjusted down. If the computed alignment is less than 8
// and the disk is bigger than SMALLEST_ADVANCED_FORMAT, resets it to 8. This
// is a safety measure for Advanced Format drives. If no partitions are
// defined, the alignment value is set to DEFAULT_ALIGNMENT (2048) (or an
// adjustment of that based on the current sector size). The result is that new
// drives are aligned to 2048-sector multiples but the program won't complain
// about other alignments on existing disks unless a smaller-than-8 alignment
// is used on big disks (as safety for Advanced Format drives).
// Returns the computed alignment value.
uint32_t GPTData::ComputeAlignment(void) {
uint32_t i = 0, found, exponent = 31;
uint32_t align = DEFAULT_ALIGNMENT;
if (blockSize > 0)
align = DEFAULT_ALIGNMENT * SECTOR_SIZE / blockSize;
exponent = (uint32_t) log2(align);
for (i = 0; i < numParts; i++) {
if (partitions[i].IsUsed()) {
found = 0;
while (!found) {
align = UINT64_C(1) << exponent;
if ((partitions[i].GetFirstLBA() % align) == 0) {
found = 1;
} else {
exponent--;
} // if/else
} // while
} // if
} // for
if ((align < MIN_AF_ALIGNMENT) && (diskSize >= SMALLEST_ADVANCED_FORMAT))
align = MIN_AF_ALIGNMENT;
sectorAlignment = align;
return align;
} // GPTData::ComputeAlignment()
/********************************
* *
* Endianness support functions *
* *
********************************/
void GPTData::ReverseHeaderBytes(struct GPTHeader* header) {
ReverseBytes(&header->signature, 8);
ReverseBytes(&header->revision, 4);
ReverseBytes(&header->headerSize, 4);
ReverseBytes(&header->headerCRC, 4);
ReverseBytes(&header->reserved, 4);
ReverseBytes(&header->currentLBA, 8);
ReverseBytes(&header->backupLBA, 8);
ReverseBytes(&header->firstUsableLBA, 8);
ReverseBytes(&header->lastUsableLBA, 8);
ReverseBytes(&header->partitionEntriesLBA, 8);
ReverseBytes(&header->numParts, 4);
ReverseBytes(&header->sizeOfPartitionEntries, 4);
ReverseBytes(&header->partitionEntriesCRC, 4);
ReverseBytes(header->reserved2, GPT_RESERVED);
} // GPTData::ReverseHeaderBytes()
// Reverse byte order for all partitions.
void GPTData::ReversePartitionBytes() {
uint32_t i;
for (i = 0; i < numParts; i++) {
partitions[i].ReversePartBytes();
} // for
} // GPTData::ReversePartitionBytes()
// Validate partition number
bool GPTData::ValidPartNum (const uint32_t partNum) {
if (partNum >= numParts) {
cerr << "Partition number out of range: " << partNum << "\n";
return false;
} // if
return true;
} // GPTData::ValidPartNum
// Return a single partition for inspection (not modification!) by other
// functions.
const GPTPart & GPTData::operator[](uint32_t partNum) const {
if (partNum >= numParts) {
cerr << "Partition number out of range (" << partNum << " requested, but only "
<< numParts << " available)\n";
exit(1);
} // if
if (partitions == NULL) {
cerr << "No partitions defined in GPTData::operator[]; fatal error!\n";
exit(1);
} // if
return partitions[partNum];
} // operator[]
// Return (not for modification!) the disk's GUID value
const GUIDData & GPTData::GetDiskGUID(void) const {
return mainHeader.diskGUID;
} // GPTData::GetDiskGUID()
// Manage attributes for a partition, based on commands passed to this function.
// (Function is non-interactive.)
// Returns 1 if a modification command succeeded, 0 if the command should not have
// modified data, and -1 if a modification command failed.
int GPTData::ManageAttributes(int partNum, const string & command, const string & bits) {
int retval = 0;
Attributes theAttr;
if (partNum >= (int) numParts) {
cerr << "Invalid partition number (" << partNum + 1 << ")\n";
retval = -1;
} else {
if (command == "show") {
ShowAttributes(partNum);
} else if (command == "get") {
GetAttribute(partNum, bits);
} else {
theAttr = partitions[partNum].GetAttributes();
if (theAttr.OperateOnAttributes(partNum, command, bits)) {
partitions[partNum].SetAttributes(theAttr.GetAttributes());
retval = 1;
} else {
retval = -1;
} // if/else
} // if/elseif/else
} // if/else invalid partition #
return retval;
} // GPTData::ManageAttributes()
// Show all attributes for a specified partition....
void GPTData::ShowAttributes(const uint32_t partNum) {
if ((partNum < numParts) && partitions[partNum].IsUsed())
partitions[partNum].ShowAttributes(partNum);
} // GPTData::ShowAttributes
// Show whether a single attribute bit is set (terse output)...
void GPTData::GetAttribute(const uint32_t partNum, const string& attributeBits) {
if (partNum < numParts)
partitions[partNum].GetAttributes().OperateOnAttributes(partNum, "get", attributeBits);
} // GPTData::GetAttribute
/******************************************
* *
* Additional non-class support functions *
* *
******************************************/
// Check to be sure that data type sizes are correct. The basic types (uint*_t) should
// never fail these tests, but the struct types may fail depending on compile options.
// Specifically, the -fpack-struct option to gcc may be required to ensure proper structure
// sizes.
int SizesOK(void) {
int allOK = 1;
if (sizeof(uint8_t) != 1) {
cerr << "uint8_t is " << sizeof(uint8_t) << " bytes, should be 1 byte; aborting!\n";
allOK = 0;
} // if
if (sizeof(uint16_t) != 2) {
cerr << "uint16_t is " << sizeof(uint16_t) << " bytes, should be 2 bytes; aborting!\n";
allOK = 0;
} // if
if (sizeof(uint32_t) != 4) {
cerr << "uint32_t is " << sizeof(uint32_t) << " bytes, should be 4 bytes; aborting!\n";
allOK = 0;
} // if
if (sizeof(uint64_t) != 8) {
cerr << "uint64_t is " << sizeof(uint64_t) << " bytes, should be 8 bytes; aborting!\n";
allOK = 0;
} // if
if (sizeof(struct MBRRecord) != 16) {
cerr << "MBRRecord is " << sizeof(MBRRecord) << " bytes, should be 16 bytes; aborting!\n";
allOK = 0;
} // if
if (sizeof(struct TempMBR) != 512) {
cerr << "TempMBR is " << sizeof(TempMBR) << " bytes, should be 512 bytes; aborting!\n";
allOK = 0;
} // if
if (sizeof(struct GPTHeader) != 512) {
cerr << "GPTHeader is " << sizeof(GPTHeader) << " bytes, should be 512 bytes; aborting!\n";
allOK = 0;
} // if
if (sizeof(GPTPart) != 128) {
cerr << "GPTPart is " << sizeof(GPTPart) << " bytes, should be 128 bytes; aborting!\n";
allOK = 0;
} // if
if (sizeof(GUIDData) != 16) {
cerr << "GUIDData is " << sizeof(GUIDData) << " bytes, should be 16 bytes; aborting!\n";
allOK = 0;
} // if
if (sizeof(PartType) != 16) {
cerr << "PartType is " << sizeof(PartType) << " bytes, should be 16 bytes; aborting!\n";
allOK = 0;
} // if
return (allOK);
} // SizesOK()