private void InvalidateSidebandFile(string sidebandFile, SidebandIntegrityCheckFailReason kind)
{
XAssert.FileExists(sidebandFile, "Sideband file for pipA not found.");
switch (kind)
{
case SidebandIntegrityCheckFailReason.FileNotFound:
AssertDeleteFile(sidebandFile, "Could not delete sideband file for pipA.");
break;
case SidebandIntegrityCheckFailReason.ChecksumMismatch:
File.WriteAllText(path: sidebandFile, contents: "bogus sideband file");
break;
case SidebandIntegrityCheckFailReason.MetadataMismatch:
SidebandMetadata alteredMetadata;
// read the header and the metadata from the original
using (var reader = new SidebandReader(sidebandFile))
{
XAssert.IsTrue(reader.ReadHeader(ignoreChecksum: false));
var originalMetadata = reader.ReadMetadata();
alteredMetadata = new SidebandMetadata(originalMetadata.PipSemiStableHash + 1, originalMetadata.StaticPipFingerprint);
}
// overwrite the original with a different metadata file where PiPSemiStableHash is different than in the original
using (var writer = new SidebandWriter(alteredMetadata, sidebandFile, null))
{
writer.EnsureHeaderWritten();
}
break;
default:
XAssert.Fail($"Unknown kind: {kind}");
break;
}
}
/// <summary>
/// Checks that
/// - a sideband file for a given process exists
/// - the sideband file is not corrupt (its checksum checks out)
/// - the process metadata recorded in the sideband file matches the metadata expected for this process
/// </summary>
private bool ValidateSidebandFileForProcess(Process process)
{
var sidebandFile = GetSidebandFile(process);
if (!FileUtilities.FileExistsNoFollow(sidebandFile))
{
return(failed(SidebandIntegrityCheckFailReason.FileNotFound));
}
using (var reader = new SidebandReader(sidebandFile))
{
if (!reader.ReadHeader(ignoreChecksum: false))
{
return(failed(SidebandIntegrityCheckFailReason.ChecksumMismatch));
}
var metadata = reader.ReadMetadata();
var expected = PipExecutor.CreateSidebandMetadata(Scheduler, process);
if (!metadata.Equals(expected))
{
return(failed(SidebandIntegrityCheckFailReason.MetadataMismatch, $"Expected: {expected}. Actual: {metadata}"));
}
return(true);
}
bool failed(SidebandIntegrityCheckFailReason reason, string details = "")
{
Logger.Log.SidebandIntegrityCheckForProcessFailed(LoggingContext, process.FormattedSemiStableHash, sidebandFile, reason.ToString(), details);
return(false);
}
}
/// <summary>
/// Checks that
/// - a sideband file for a given process exists
/// - the sideband file is not corrupt (its checksum checks out)
/// - the process metadata recorded in the sideband file matches the metadata expected for this process
/// Returns true on success and the sideband state in the out parameter
/// </summary>
private bool TryGetAndValidateSidebandStateForProcess(Process process, out IReadOnlyCollection <AbsolutePath> paths)
{
var sidebandFile = GetSidebandFile(process);
paths = null;
if (!FileUtilities.FileExistsNoFollow(sidebandFile))
{
return(failed(SidebandIntegrityCheckFailReason.FileNotFound));
}
using (var reader = new SidebandReader(sidebandFile))
{
if (!reader.ReadHeader(ignoreChecksum: false))
{
return(failed(SidebandIntegrityCheckFailReason.ChecksumMismatch));
}
var metadata = reader.ReadMetadata();
var expected = PipExecutor.CreateSidebandMetadata(Scheduler, process);
if (!metadata.Equals(expected))
{
return(failed(SidebandIntegrityCheckFailReason.MetadataMismatch, $"Expected: {expected}. Actual: {metadata}"));
}
paths = reader.ReadRecordedPaths().Select(p => AbsolutePath.Create(Context.PathTable, p)).ToHashSet();
return(true);
}
bool failed(SidebandIntegrityCheckFailReason reason, string details = "")
{
Logger.Log.SidebandIntegrityCheckForProcessFailed(LoggingContext, process.FormattedSemiStableHash, sidebandFile, reason.ToString(), details);
return(false);
}
}