| /* bsd.cc -- Functions for loading and manipulating legacy BSD disklabel |
| data. */ |
| |
| /* By Rod Smith, initial coding August, 2009 */ |
| |
| /* This program is copyright (c) 2009 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 <unistd.h> |
| #include <stdlib.h> |
| #include <stdint.h> |
| #include <fcntl.h> |
| #include <sys/stat.h> |
| #include <errno.h> |
| #include <iostream> |
| #include <string> |
| #include "support.h" |
| #include "bsd.h" |
| |
| using namespace std; |
| |
| |
| BSDData::BSDData(void) { |
| state = unknown; |
| signature = UINT32_C(0); |
| signature2 = UINT32_C(0); |
| sectorSize = 512; |
| numParts = 0; |
| labelFirstLBA = 0; |
| labelLastLBA = 0; |
| labelStart = LABEL_OFFSET1; // assume raw disk format |
| partitions = NULL; |
| } // default constructor |
| |
| BSDData::~BSDData(void) { |
| delete[] partitions; |
| } // destructor |
| |
| // Read BSD disklabel data from the specified device filename. This function |
| // just opens the device file and then calls an overloaded function to do |
| // the bulk of the work. Returns 1 on success, 0 on failure. |
| int BSDData::ReadBSDData(const string & device, uint64_t startSector, uint64_t endSector) { |
| int allOK = 1; |
| DiskIO myDisk; |
| |
| if (device != "") { |
| if (myDisk.OpenForRead(device)) { |
| allOK = ReadBSDData(&myDisk, startSector, endSector); |
| } else { |
| allOK = 0; |
| } // if/else |
| |
| myDisk.Close(); |
| } else { |
| allOK = 0; |
| } // if/else |
| return allOK; |
| } // BSDData::ReadBSDData() (device filename version) |
| |
| // Load the BSD disklabel data from an already-opened disk |
| // file, starting with the specified sector number. |
| int BSDData::ReadBSDData(DiskIO *theDisk, uint64_t startSector, uint64_t endSector) { |
| int allOK = 1; |
| int i, foundSig = 0, bigEnd = 0; |
| int relative = 0; // assume absolute partition sector numbering |
| uint8_t buffer[4096]; // I/O buffer |
| uint32_t realSig; |
| uint32_t* temp32; |
| uint16_t* temp16; |
| BSDRecord* tempRecords; |
| int offset[NUM_OFFSETS] = { LABEL_OFFSET1, LABEL_OFFSET2 }; |
| |
| labelFirstLBA = startSector; |
| labelLastLBA = endSector; |
| offset[1] = theDisk->GetBlockSize(); |
| |
| // Read 4096 bytes (eight 512-byte sectors or equivalent) |
| // into memory; we'll extract data from this buffer. |
| // (Done to work around FreeBSD limitation on size of reads |
| // from block devices.) |
| allOK = theDisk->Seek(startSector); |
| if (allOK) allOK = theDisk->Read(buffer, 4096); |
| |
| // Do some strangeness to support big-endian architectures... |
| bigEnd = (IsLittleEndian() == 0); |
| realSig = BSD_SIGNATURE; |
| if (bigEnd && allOK) |
| ReverseBytes(&realSig, 4); |
| |
| // Look for the signature at any of two locations. |
| // Note that the signature is repeated at both the original |
| // offset and 132 bytes later, so we need two checks.... |
| if (allOK) { |
| i = 0; |
| do { |
| temp32 = (uint32_t*) &buffer[offset[i]]; |
| signature = *temp32; |
| if (signature == realSig) { // found first, look for second |
| temp32 = (uint32_t*) &buffer[offset[i] + 132]; |
| signature2 = *temp32; |
| if (signature2 == realSig) { |
| foundSig = 1; |
| labelStart = offset[i]; |
| } // if found signature |
| } // if/else |
| i++; |
| } while ((!foundSig) && (i < NUM_OFFSETS)); |
| allOK = foundSig; |
| } // if |
| |
| // Load partition metadata from the buffer.... |
| if (allOK) { |
| temp32 = (uint32_t*) &buffer[labelStart + 40]; |
| sectorSize = *temp32; |
| temp16 = (uint16_t*) &buffer[labelStart + 138]; |
| numParts = *temp16; |
| } // if |
| |
| // Make it big-endian-aware.... |
| if ((IsLittleEndian() == 0) && allOK) |
| ReverseMetaBytes(); |
| |
| // Check validity of the data and flag it appropriately.... |
| if (foundSig && (numParts <= MAX_BSD_PARTS) && allOK) { |
| state = bsd; |
| } else { |
| state = bsd_invalid; |
| } // if/else |
| |
| // If the state is good, go ahead and load the main partition data.... |
| if (state == bsd) { |
| partitions = new struct BSDRecord[numParts * sizeof(struct BSDRecord)]; |
| if (partitions == NULL) { |
| cerr << "Unable to allocate memory in BSDData::ReadBSDData()! Terminating!\n"; |
| exit(1); |
| } // if |
| for (i = 0; i < numParts; i++) { |
| // Once again, we use the buffer, but index it using a BSDRecord |
| // pointer (dangerous, but effective).... |
| tempRecords = (BSDRecord*) &buffer[labelStart + 148]; |
| partitions[i].lengthLBA = tempRecords[i].lengthLBA; |
| partitions[i].firstLBA = tempRecords[i].firstLBA; |
| partitions[i].fsType = tempRecords[i].fsType; |
| if (bigEnd) { // reverse data (fsType is a single byte) |
| ReverseBytes(&partitions[i].lengthLBA, 4); |
| ReverseBytes(&partitions[i].firstLBA, 4); |
| } // if big-endian |
| // Check for signs of relative sector numbering: A "0" first sector |
| // number on a partition with a non-zero length -- but ONLY if the |
| // length is less than the disk size, since NetBSD has a habit of |
| // creating a disk-sized partition within a carrier MBR partition |
| // that's too small to house it, and this throws off everything.... |
| if ((partitions[i].firstLBA == 0) && (partitions[i].lengthLBA > 0) |
| && (partitions[i].lengthLBA < labelLastLBA)) |
| relative = 1; |
| } // for |
| // Some disklabels use sector numbers relative to the enclosing partition's |
| // start, others use absolute sector numbers. If relative numbering was |
| // detected above, apply a correction to all partition start sectors.... |
| if (relative) { |
| for (i = 0; i < numParts; i++) { |
| partitions[i].firstLBA += (uint32_t) startSector; |
| } // for |
| } // if |
| } // if signatures OK |
| // DisplayBSDData(); |
| return allOK; |
| } // BSDData::ReadBSDData(DiskIO* theDisk, uint64_t startSector) |
| |
| // Reverse metadata's byte order; called only on big-endian systems |
| void BSDData::ReverseMetaBytes(void) { |
| ReverseBytes(&signature, 4); |
| ReverseBytes(§orSize, 4); |
| ReverseBytes(&signature2, 4); |
| ReverseBytes(&numParts, 2); |
| } // BSDData::ReverseMetaByteOrder() |
| |
| // Display basic BSD partition data. Used for debugging. |
| void BSDData::DisplayBSDData(void) { |
| int i; |
| |
| if (state == bsd) { |
| cout << "BSD partitions:\n"; |
| for (i = 0; i < numParts; i++) { |
| cout.width(4); |
| cout << i + 1 << "\t"; |
| cout.width(13); |
| cout << partitions[i].firstLBA << "\t"; |
| cout.width(15); |
| cout << partitions[i].lengthLBA << " \t0x"; |
| cout.width(2); |
| cout.fill('0'); |
| cout.setf(ios::uppercase); |
| cout << hex << (int) partitions[i].fsType << "\n" << dec; |
| cout.fill(' '); |
| } // for |
| } // if |
| } // BSDData::DisplayBSDData() |
| |
| // Displays the BSD disklabel state. Called during program launch to inform |
| // the user about the partition table(s) status |
| int BSDData::ShowState(void) { |
| int retval = 0; |
| |
| switch (state) { |
| case bsd_invalid: |
| cout << " BSD: not present\n"; |
| break; |
| case bsd: |
| cout << " BSD: present\n"; |
| retval = 1; |
| break; |
| default: |
| cout << "\a BSD: unknown -- bug!\n"; |
| break; |
| } // switch |
| return retval; |
| } // BSDData::ShowState() |
| |
| // Weirdly, this function has stopped working when defined inline, |
| // but it's OK here.... |
| int BSDData::IsDisklabel(void) { |
| return (state == bsd); |
| } // BSDData::IsDiskLabel() |
| |
| // Returns the BSD table's partition type code |
| uint8_t BSDData::GetType(int i) { |
| uint8_t retval = 0; // 0 = "unused" |
| |
| if ((i < numParts) && (i >= 0) && (state == bsd) && (partitions != 0)) |
| retval = partitions[i].fsType; |
| |
| return(retval); |
| } // BSDData::GetType() |
| |
| // Returns the number of the first sector of the specified partition |
| uint64_t BSDData::GetFirstSector(int i) { |
| uint64_t retval = UINT64_C(0); |
| |
| if ((i < numParts) && (i >= 0) && (state == bsd) && (partitions != 0)) |
| retval = (uint64_t) partitions[i].firstLBA; |
| |
| return retval; |
| } // BSDData::GetFirstSector |
| |
| // Returns the length (in sectors) of the specified partition |
| uint64_t BSDData::GetLength(int i) { |
| uint64_t retval = UINT64_C(0); |
| |
| if ((i < numParts) && (i >= 0) && (state == bsd) && (partitions != 0)) |
| retval = (uint64_t) partitions[i].lengthLBA; |
| |
| return retval; |
| } // BSDData::GetLength() |
| |
| // Returns the number of partitions defined in the current table |
| int BSDData::GetNumParts(void) { |
| return numParts; |
| } // BSDData::GetNumParts() |
| |
| // Returns the specified partition as a GPT partition. Used in BSD-to-GPT |
| // conversion process |
| GPTPart BSDData::AsGPT(int i) { |
| GPTPart guid; // dump data in here, then return it |
| uint64_t sectorOne, sectorEnd; // first & last sectors of partition |
| int passItOn = 1; // Set to 0 if partition is empty or invalid |
| |
| guid.BlankPartition(); |
| sectorOne = (uint64_t) partitions[i].firstLBA; |
| sectorEnd = sectorOne + (uint64_t) partitions[i].lengthLBA; |
| if (sectorEnd > 0) sectorEnd--; |
| // Note on above: BSD partitions sometimes have a length of 0 and a start |
| // sector of 0. With unsigned ints, the usual way (start + length - 1) to |
| // find the end will result in a huge number, which will be confusing. |
| // Thus, apply the "-1" part only if it's reasonable to do so. |
| |
| // Do a few sanity checks on the partition before we pass it on.... |
| // First, check that it falls within the bounds of its container |
| // and that it starts before it ends.... |
| if ((sectorOne < labelFirstLBA) || (sectorEnd > labelLastLBA) || (sectorOne > sectorEnd)) |
| passItOn = 0; |
| // Some disklabels include a pseudo-partition that's the size of the entire |
| // disk or containing partition. Don't return it. |
| if ((sectorOne <= labelFirstLBA) && (sectorEnd >= labelLastLBA) && |
| (GetType(i) == 0)) |
| passItOn = 0; |
| // If the end point is 0, it's not a valid partition. |
| if ((sectorEnd == 0) || (sectorEnd == labelFirstLBA)) |
| passItOn = 0; |
| |
| if (passItOn) { |
| guid.SetFirstLBA(sectorOne); |
| guid.SetLastLBA(sectorEnd); |
| // Now set a random unique GUID for the partition.... |
| guid.RandomizeUniqueGUID(); |
| // ... zero out the attributes and name fields.... |
| guid.SetAttributes(UINT64_C(0)); |
| // Most BSD disklabel type codes seem to be archaic or rare. |
| // They're also ambiguous; a FreeBSD filesystem is impossible |
| // to distinguish from a NetBSD one. Thus, these code assignment |
| // are going to be rough to begin with. For a list of meanings, |
| // see http://fxr.watson.org/fxr/source/sys/dtype.h?v=DFBSD, |
| // or Google it. |
| switch (GetType(i)) { |
| case 1: // BSD swap |
| guid.SetType(0xa502); break; |
| case 7: // BSD FFS |
| guid.SetType(0xa503); break; |
| case 8: case 11: // MS-DOS or HPFS |
| guid.SetType(0x0700); break; |
| case 9: // log-structured fs |
| guid.SetType(0xa903); break; |
| case 13: // bootstrap |
| guid.SetType(0xa501); break; |
| case 14: // vinum |
| guid.SetType(0xa505); break; |
| case 15: // RAID |
| guid.SetType(0xa903); break; |
| case 27: // FreeBSD ZFS |
| guid.SetType(0xa504); break; |
| default: |
| guid.SetType(0xa503); break; |
| } // switch |
| // Set the partition name to the name of the type code.... |
| guid.SetName(guid.GetTypeName()); |
| } // if |
| return guid; |
| } // BSDData::AsGPT() |
