private bool VerifyFileSHA256()
{
SHA256 FileSHA = SHA256.Create();
using (BinaryReader BR = new BinaryReader(new FileStream(Path, FileMode.Open)))
{
byte[] HashValue = FileSHA.ComputeHash(BR.BaseStream);
bool Result = (HashValue.SequenceEqual(FSHA256));
Logging.Log($"SHA256 hash-based file verification in progress for file {Path}");
// Add an additional space to make comparison easier
Logging.Log($"Expected hash: {FSHA256.ByteArrayToHexString()}");
Logging.Log($"Actual hash: {HashValue.ByteArrayToHexString()}");
Logging.Log($"Result: {Result}");
return(Result);
}
}
public VerificationResult Verify()
{
// mild handling
VerificationResult VR = new VerificationResult();
VR.File = this;
// might need to change this a bit
if (Path != null)
{
VR.WasFileValid = true;
if (Strictness == VerificationStrictness.Moderate)
{
if (FSize < 0)
{
VR.WasFileValid = false;
return(VR);
}
}
else if (Strictness == VerificationStrictness.Strict)
{
if (FSize > 0 && FSHA256 != null)
{
if (FSHA256.Length != 32)
{
VR.FailureReason = $"Invalid SHA256 hash - must be 32 bytes long, was {FSHA256.Length}!";
return(VR);
}
}
else
{
VR.FailureReason = "CriticalFile entry invalid - invalid file size or null SHA256 hash!";
VR.WasFileValid = false;
return(VR);
}
}
}
else
{
// false by default
return(VR);
}
switch (Strictness)
{
case VerificationStrictness.Low:
// false by default
VR.Successful = VerifyFileExistence();
return(VR);
case VerificationStrictness.Moderate:
VR.Successful = VerifyFileExistence();
if (!VR.Successful)
{
VR.FailureReason = "File does not exist!";
return(VR);
}
VR.Successful = VerifyFileSize();
if (!VR.Successful)
{
VR.FailureReason = $"File size is invalid - should be {FSize.ToString()} bytes!";
}
return(VR);
case VerificationStrictness.Strict:
VR.Successful = VerifyFileExistence();
if (!VR.Successful)
{
VR.FailureReason = "File does not exist!";
return(VR);
}
VR.Successful = VerifyFileSize();
if (!VR.Successful)
{
VR.FailureReason = $"File size is invalid - should be {FSize.ToString()} bytes!";
return(VR);
}
VR.Successful = VerifyFileSHA256();
if (!VR.Successful)
{
VR.FailureReason = $"File is corrupted or modified - please turn on DeveloperMode if you are working with source code!\n The SHA256 hash should be {FSHA256.ByteArrayToHexString()}.";
}
return(VR);
}
// someting went wrong
return(VR);
}
