Files
BadBuilder/BadBuilder.Formatter/Utilities.cs
2025-03-17 14:26:41 -04:00

110 lines
4.3 KiB
C#

using Windows.Win32.Foundation;
using Windows.Win32.System.Memory;
using System.Runtime.InteropServices;
using static Windows.Win32.PInvoke;
using static BadBuilder.Formatter.Constants;
namespace BadBuilder.Formatter
{
static class Utilities
{
internal static byte[] StructToBytes<T>(T @struct) where T : struct
{
Span<T> structSpan = MemoryMarshal.CreateSpan(ref @struct, 1);
Span<byte> byteSpan = MemoryMarshal.AsBytes(structSpan);
return byteSpan.ToArray();
}
internal static byte[] UintArrayToBytes(uint[] array) => MemoryMarshal.AsBytes<uint>(array.AsSpan()).ToArray();
internal static string Error(string error) => $"{ORANGE}[-]{ANSI_RESET} {error}";
internal static void ExitWithError(string error)
{
Console.WriteLine($"{ORANGE}[-]{ANSI_RESET} {error}");
Environment.Exit(-1);
}
internal static uint GetVolumeID()
{
DateTime now = DateTime.Now;
ushort low = (ushort)(now.Day + (now.Month << 8));
low += (ushort)((now.Millisecond / 10) + (now.Second << 8));
ushort hi = (ushort)(now.Minute + (now.Hour << 8));
hi += (ushort)now.Year;
return (uint)(low | (hi << 16));
}
internal static uint CalculateFATSize(uint totalSectors, uint reservedSectors, uint sectorsPerCluster, uint numberOfFATs, uint bytesPerSector)
{
const ulong fatElementSize = 4;
ulong numerator = fatElementSize * (totalSectors - reservedSectors);
ulong denominator = (sectorsPerCluster * bytesPerSector) + (fatElementSize * numberOfFATs);
return (uint)((numerator / denominator) + 1);
}
internal static byte CalculateSectorsPerCluster(ulong diskSizeBytes, uint bytesPerSector) => (diskSizeBytes / (1024 * 1024)) switch
{
var size when size > 512 => (byte)((4 * 1024) / bytesPerSector),
var size when size > 8192 => (byte)((8 * 1024) / bytesPerSector),
var size when size > 16384 => (byte)((16 * 1024) / bytesPerSector),
var size when size > 32768 => (byte)((32 * 1024) / bytesPerSector),
_ => 1
};
internal static unsafe void SeekTo(SafeHandle hDevice, uint sector, uint bytesPerSector)
{
long offset = sector * bytesPerSector;
int lowOffset = (int)(offset & 0xFFFFFFFF);
int highOffset = (int)(offset >> 32);
SetFilePointer(hDevice, lowOffset, &highOffset, Windows.Win32.Storage.FileSystem.SET_FILE_POINTER_MOVE_METHOD.FILE_BEGIN);
}
internal static unsafe void WriteSector(SafeHandle hDevice, uint sector, uint numberOfSectors, uint bytesPerSector, byte[] data)
{
SeekTo(hDevice, sector, bytesPerSector);
fixed (byte* pData = &data[0])
{
if (!WriteFile(new HANDLE(hDevice.DangerousGetHandle()), pData, numberOfSectors * bytesPerSector, null, null))
ExitWithError($"Unable to write sectors to FAT32 device, exiting. GetLastError: {Marshal.GetLastWin32Error()}");
}
}
internal static unsafe void ZeroOutSectors(SafeHandle hDevice, uint sector, uint numberOfSectors, uint bytesPerSector)
{
const uint burstSize = 128;
uint writeSize;
byte* pZeroSector = (byte*)VirtualAlloc(null, bytesPerSector * burstSize, VIRTUAL_ALLOCATION_TYPE.MEM_COMMIT | VIRTUAL_ALLOCATION_TYPE.MEM_RESERVE, PAGE_PROTECTION_FLAGS.PAGE_READWRITE);
try
{
SeekTo(hDevice, sector, bytesPerSector);
while (numberOfSectors > 0)
{
writeSize = (numberOfSectors > burstSize) ? burstSize : numberOfSectors;
if (!WriteFile(new HANDLE(hDevice.DangerousGetHandle()), pZeroSector, writeSize * bytesPerSector, null, null))
ExitWithError($"Unable to write sectors to FAT32 device, exiting. GetLastError: {Marshal.GetLastWin32Error()}");
numberOfSectors -= writeSize;
}
}
finally
{
VirtualFree(pZeroSector, bytesPerSector * burstSize, VIRTUAL_FREE_TYPE.MEM_RELEASE);
}
}
}
}