/// <summary>
/// Opens a properly-formed TPM command stream into its constituent components.
/// Note: commandParams does NOT include handles.
/// </summary>
/// <param name="command"></param>
/// <param name="header"></param>
/// <param name="handles"></param>
/// <param name="sessions"></param>
/// <param name="commandParms"></param>
public static bool CrackCommand(
byte[] command,
out CommandHeader header,
out TpmHandle[] handles,
out SessionIn[] sessions,
out byte[] commandParms)
{
var m = new Marshaller(command);
header = m.Get<CommandHeader>();
CommandInfo commandInfo = Tpm2.CommandInfoFromCommandCode(header.CommandCode);
if (header.Tag == TpmSt.Null)
{
// A diagnostics command. Pass through unmodified
handles = null;
sessions = null;
commandParms = null;
return false;
}
handles = new TpmHandle[commandInfo.HandleCountIn];
for (int j = 0; j < handles.Length; j++)
{
handles[j] = m.Get<TpmHandle>();
}
// Note sessions are only present if the command tag indicates sessions
if (header.Tag == TpmSt.Sessions)
{
var sessionLength = m.Get<uint>();
uint sessionEnd = m.GetGetPos() + sessionLength;
var inSessions = new List<SessionIn>();
while (m.GetGetPos() < sessionEnd)
{
var s = m.Get<SessionIn>();
inSessions.Add(s);
}
sessions = inSessions.ToArray();
}
else
{
sessions = new SessionIn[0];
}
// And finally parameters
commandParms = m.GetArray<byte>((int)(m.GetValidLength() - m.GetGetPos()));
if (m.GetValidLength() != header.CommandSize)
{
throw new Exception("Command length in header does not match input byte-stream");
}
return true;
}
public static void SplitResponse(
byte[] response,
uint numHandles,
out TpmSt tag,
out uint paramSize,
out TpmRc responseCode,
out TpmHandle[] handles,
out SessionOut[] sessions,
out byte[] responseParmsNoHandles,
out byte[] responseParmsWithHandles)
{
var m = new Marshaller(response);
tag = m.Get<TpmSt>();
paramSize = m.Get<uint>();
responseCode = m.Get<TpmRc>();
// If error we only get the header
if (responseCode != TpmRc.Success)
{
handles = new TpmHandle[0];
sessions = new SessionOut[0];
responseParmsNoHandles = new byte[0];
responseParmsWithHandles = new byte[0];
return;
}
handles = new TpmHandle[numHandles];
for (int j = 0; j < numHandles; j++)
{
handles[j] = m.Get<TpmHandle>();
}
uint parmsEnd = m.GetValidLength();
if (tag == TpmSt.Sessions)
{
var sessionOffset = m.Get<uint>();
uint startOfParmsX = m.GetGetPos();
parmsEnd = startOfParmsX + sessionOffset;
m.SetGetPos(parmsEnd);
var sessX = new List<SessionOut>();
while (m.GetGetPos() < m.GetValidLength())
{
var s = m.Get<SessionOut>();
sessX.Add(s);
}
sessions = sessX.ToArray();
m.SetGetPos(startOfParmsX);
}
else
{
sessions = new SessionOut[0];
}
uint startOfParms = m.GetGetPos();
uint parmsLength = parmsEnd - m.GetGetPos();
// Get the response buf with no handles
responseParmsNoHandles = new byte[parmsLength];
Array.Copy(response, (int)startOfParms, responseParmsNoHandles, 0, (int)parmsLength);
// Get the response buf with handles
responseParmsWithHandles = new byte[parmsLength + numHandles * 4];
Array.Copy(response, 10, responseParmsWithHandles, 0, (int)numHandles * 4);
Array.Copy(response, (int)startOfParms, responseParmsWithHandles, (int)numHandles * 4, (int)parmsLength);
}
/// <summary>
/// DispatchMethod is called by auto-generated command action code. It assembles a byte[] containing
/// the formatted TPM command based on the params passed in explicitly, and the sessions currently attached
/// to the TPM object. It processes the TPM response and converts it into an instantiation of the
/// requested object.
/// </summary>
/// <param name="ordinal"></param>
/// <param name="inParms"></param>
/// <param name="expectedResponseType"></param>
/// <param name="outParms"></param>
/// <param name="numInHandlesNotUsed"></param>
/// <param name="numOutHandlesNotUsed"></param>
/// <returns></returns>
internal bool DispatchMethod(
TpmCc ordinal,
TpmStructureBase inParms,
Type expectedResponseType,
out TpmStructureBase outParms,
int numInHandlesNotUsed,
int numOutHandlesNotUsed)
{
outParms = null;
// todo - ClearCommandContext should be moved to the front of this
// routine (and we should make local copies of the context-values we depend upon)
// There are uncaught exceptions that can be generated that would skip
// ClearCOmmandCOntext and leave the Tpm2 with some leftover state.
byte[] response;
if (CurrentCommand != TpmCc.None)
{
OuterCommand = CurrentCommand;
}
CurrentCommand = ordinal;
// The AlternateActionCallback allows alternate processing (or filtering/data
// collection on the executing command stream.
if (TheAlternateActionCallback != null)
{
bool desiredSuccessCode;
bool alternate = TheAlternateActionCallback(ordinal,
inParms,
expectedResponseType,
out outParms,
out desiredSuccessCode);
if (alternate)
{
_ClearCommandContext();
return desiredSuccessCode;
}
}
CommandInfo commandInfo = CommandInfoFromCommandCode(ordinal);
byte[] parms;
TpmHandle[] inHandles;
try
{
// Get the handles and the parameters from the command input structure
CommandProcessor.Fragment(inParms, commandInfo.HandleCountIn, out inHandles, out parms);
// Start processing sessions
PrepareRequestSessions(commandInfo, inHandles);
}
catch (Exception e)
{
Debug.Assert(outParms == null);
if (e is TpmException)
{
if (IsErrorAllowed(((TpmException)e).RawResponse))
{
outParms = (TpmStructureBase)Activator.CreateInstance(expectedResponseType);
}
}
_ClearCommandPrelaunchContext();
_ClearCommandContext();
if (outParms != null)
{
return false;
}
throw;
}
// The caller can install observer/modifier callbacks, and request repeated
// execution of the same command.
bool repeat = false;
byte[] parmsCopy = null;
if (TheCmdParamsCallback != null)
{
parmsCopy = Globs.CopyData(parms);
}
// Response atoms
TpmSt responseTag;
TpmRc resultCode;
uint responseParamSize;
byte[] outParmsNoHandles, outParmsWithHandles;
TpmHandle[] outHandles;
SessionOut[] outSessions;
// In normal processing there is just one pass through this do-while loop
// If command observation/modification callbacks are installed, then the
// caller repeats the command as long as necessary.
bool invokeCallbacks = OuterCommand == TpmCc.None && !CpHashMode && !DoNotDispatchCommand;
do try
{
if (TheCmdParamsCallback != null && invokeCallbacks)
{
parms = Globs.CopyData(parmsCopy);
TheCmdParamsCallback(commandInfo, ref parms, inHandles);
}
// If there are any encrypting sessions then next we encrypt the data in place
parms = DoParmEncryption(parms, commandInfo, 0, Direction.Command);
// Now do the HMAC (note that the handles are needed for name-replacement)
SessionIn[] inSessions = CreateRequestSessions(parms, inHandles);
// CpHashMode is enabled for a single command through tpm.GetCpHash().TpmCommand(...)
if (OuterCommand == TpmCc.None && CpHashMode)
{
CommandParmHash.HashData = GetCommandHash(CommandParmHash.HashAlg, parms, inHandles);
outParms = (TpmStructureBase)Activator.CreateInstance(expectedResponseType);
CpHashMode = false;
_ClearCommandContext();
return true;
}
// Create the command buffer
byte[] command = CommandProcessor.CreateCommand(ordinal, inHandles, inSessions, parms);
// And dispatch the command
Log(ordinal, inParms, 0);
if (DoNotDispatchCommand)
{
CommandBytes = command;
outParms = (TpmStructureBase)Activator.CreateInstance(expectedResponseType);
DoNotDispatchCommand = false;
_ClearCommandContext();
return true;
}
if (TheCmdBufCallback != null && invokeCallbacks)
{
TheCmdBufCallback(ref command);
}
// And actually dispatch the command into the underlying device
DateTime commandSentTime, responseReceivedTime;
int nvRateRecoveryCount = 0;
// No more than 4 retries on NV_RATE error
for (;;)
{
responseReceivedTime = commandSentTime = DateTime.Now;
if (!TestCycleNv)
{
commandSentTime = DateTime.Now;
Device.DispatchCommand(ActiveModifiers, command, out response);
responseReceivedTime = DateTime.Now;
}
else
{
// In TestCycleNv we submit the command with NV not-available. If the TPM indicates that
// NV is not available we re-submit.
try
{
// Once with NV off
Device.SignalNvOff();
Device.DispatchCommand(ActiveModifiers, command, out response);
Device.SignalNvOn();
// And if it did not work, try again with NV on
TpmRc respCode = CommandProcessor.GetResponseCode(response);
if ((uint)respCode == 0x923U || respCode == TpmRc.Lockout)
{
Device.DispatchCommand(ActiveModifiers, command, out response);
}
}
catch (Exception)
{
Device.SignalNvOn();
throw;
}
}
// Convert the byte[] response into its constituent parts.
CommandProcessor.SplitResponse(response,
commandInfo.HandleCountOut,
out responseTag,
out responseParamSize,
out resultCode,
out outHandles,
out outSessions,
out outParmsNoHandles,
out outParmsWithHandles);
if (resultCode != TpmRc.NvRate || ++nvRateRecoveryCount > 4)
{
break;
}
//Console.WriteLine(">>>> NV_RATE: Retrying... Attempt {0}", nvRateRecoveryCount);
Thread.Sleep((int)Tpm2.GetProperty(this, Pt.NvWriteRecovery) + 100);
}
// Invoke the trace callback if installed
if (TheTraceCallback != null)
{
TheTraceCallback(command, response);
}
// Collect basic statistics on command execution
if (TheCmdStatsCallback != null && invokeCallbacks)
{
repeat = TheCmdStatsCallback(ordinal, GetBaseErrorCode(resultCode),
(responseReceivedTime - commandSentTime).TotalSeconds);
}
if (repeat && resultCode == TpmRc.Success)
{
// Update session state
ProcessResponseSessions(outSessions);
int offset = (int)commandInfo.HandleCountOut * 4;
outParmsWithHandles = DoParmEncryption(outParmsWithHandles, commandInfo, offset, Direction.Response);
var m = new Marshaller(outParmsWithHandles);
outParms = (TpmStructureBase)m.Get(expectedResponseType, "");
#if false
m = new Marshaller(command);
TpmSt tag = m.Get<TpmSt>();
uint cmdSize = m.Get<uint>();
TpmCc actualCmd = m.Get<TpmCc>();
var actualHandles = new TpmHandle[inHandles.Length];
for (int i = 0; i < inHandles.Length; ++i)
{
actualHandles[i] = m.Get<TpmHandle>();
}
for (int i = 0; i < inSessions.Length; ++i)
{
m.Get<SessionIn>();
}
var actualParms = m.GetArray<byte>(m.GetValidLength() - m.GetGetPos());
if (m.GetValidLength() != cmdSize)
{
throw new Exception("Command length in header does not match input byte-stream");
}
#endif
CommandHeader actualHeader;
TpmHandle[] actualHandles;
SessionIn[] actualSessions;
byte[] actualParmsBuf;
CommandProcessor.CrackCommand(command, out actualHeader, out actualHandles, out actualSessions, out actualParmsBuf);
m = new Marshaller();
foreach (TpmHandle h in actualHandles)
{
m.Put(h, "handle");
}
m.Put(actualParmsBuf, "parms");
var actualParms = (TpmStructureBase)Activator.CreateInstance(inParms.GetType());
actualParms.ToHost(m);
UpdateHandleData(actualHeader.CommandCode, actualParms, actualHandles, outParms);
//ValidateResponseSessions(outHandles, outSessions, ordinal, resultCode, outParmsNoHandles);
foreach (var h in outHandles)
{
CancelSafeFlushContext(h);
}
} // if (repeat && resultCode == TpmRc.Success)
}
catch (Exception)
{
_ClearCommandPrelaunchContext();
_ClearCommandContext();
throw;
}
while (repeat);
// Update the audit session if needed
if (AuditThisCommand)
{
AuditThisCommand = false;
if (CommandAuditHash == null)
throw new Exception("No audit hash set for this command stream");
byte[] parmHash = GetCommandHash(CommandAuditHash.HashAlg, parms, inHandles);
byte[] expectedResponseHash = GetExpectedResponseHash(CommandAuditHash.HashAlg,
outParmsNoHandles,
ordinal,
resultCode);
CommandAuditHash.Extend(Globs.Concatenate(parmHash, expectedResponseHash));
}
// FlushContest that may be executed as part of _ClearCommandPrelaunchContext()
// must be executed before any command-related info is updated.
_ClearCommandPrelaunchContext();
// Process errors if there are any
bool commandSucceeded = ProcessError(responseTag, responseParamSize, resultCode, inParms);
try
{
if (commandSucceeded)
{
ProcessResponseSessions(outSessions);
int offset = (int)commandInfo.HandleCountOut * 4;
outParmsWithHandles = DoParmEncryption(outParmsWithHandles, commandInfo, offset, Direction.Response);
var mt = new Marshaller(outParmsWithHandles);
outParms = (TpmStructureBase)mt.Get(expectedResponseType, "");
if (TheParamsTraceCallback != null)
{
TheParamsTraceCallback(ordinal, inParms, outParms);
}
UpdateHandleData(ordinal, inParms, inHandles, outParms);
ValidateResponseSessions(outHandles, outSessions, ordinal, resultCode, outParmsNoHandles);
foreach (var s in Sessions) if (s is AuthSession)
{
var sess = s as AuthSession;
if (sess.Attrs.HasFlag(SessionAttr.Audit) && !TpmHandle.IsNull(sess.BindObject))
{
sess.BindObject = TpmRh.Null;
break; // only one audit session is expected
}
}
}
else
{
outParms = (TpmStructureBase)Activator.CreateInstance(expectedResponseType);
}
}
finally
{
// Check in case an exception happened before outParms was initialized
// ReSharper disable once CSharpWarnings::CS0183
if (outParms is TpmStructureBase)
{
Log(ordinal, outParms, 1);
}
// Clear all per-invocation state (e.g. sessions, errors expected) ready for next command
_ClearCommandContext();
}
return commandSucceeded;
}
