| protected static GetPrfAlgorithm ( TlsContext context, int ciphersuite ) : int | ||
| context | TlsContext | |
| ciphersuite | int | |
| return | int | |
protected virtual byte[] GenerateServerHello(DtlsServerProtocol.ServerHandshakeState state)
{
SecurityParameters securityParameters = state.serverContext.SecurityParameters;
MemoryStream memoryStream = new MemoryStream();
ProtocolVersion serverVersion = state.server.GetServerVersion();
if (!serverVersion.IsEqualOrEarlierVersionOf(state.serverContext.ClientVersion))
{
throw new TlsFatalAlert(80);
}
state.serverContext.SetServerVersion(serverVersion);
TlsUtilities.WriteVersion(state.serverContext.ServerVersion, memoryStream);
memoryStream.Write(securityParameters.ServerRandom, 0, securityParameters.ServerRandom.Length);
TlsUtilities.WriteOpaque8(TlsUtilities.EmptyBytes, memoryStream);
int selectedCipherSuite = state.server.GetSelectedCipherSuite();
if (!Arrays.Contains(state.offeredCipherSuites, selectedCipherSuite) || selectedCipherSuite == 0 || CipherSuite.IsScsv(selectedCipherSuite) || !TlsUtilities.IsValidCipherSuiteForVersion(selectedCipherSuite, state.serverContext.ServerVersion))
{
throw new TlsFatalAlert(80);
}
DtlsProtocol.ValidateSelectedCipherSuite(selectedCipherSuite, 80);
securityParameters.cipherSuite = selectedCipherSuite;
byte selectedCompressionMethod = state.server.GetSelectedCompressionMethod();
if (!Arrays.Contains(state.offeredCompressionMethods, selectedCompressionMethod))
{
throw new TlsFatalAlert(80);
}
securityParameters.compressionAlgorithm = selectedCompressionMethod;
TlsUtilities.WriteUint16(selectedCipherSuite, memoryStream);
TlsUtilities.WriteUint8(selectedCompressionMethod, memoryStream);
state.serverExtensions = state.server.GetServerExtensions();
if (state.secure_renegotiation)
{
byte[] extensionData = TlsUtilities.GetExtensionData(state.serverExtensions, 65281);
bool flag = null == extensionData;
if (flag)
{
state.serverExtensions = TlsExtensionsUtilities.EnsureExtensionsInitialised(state.serverExtensions);
state.serverExtensions[65281] = TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes);
}
}
if (securityParameters.extendedMasterSecret)
{
state.serverExtensions = TlsExtensionsUtilities.EnsureExtensionsInitialised(state.serverExtensions);
TlsExtensionsUtilities.AddExtendedMasterSecretExtension(state.serverExtensions);
}
if (state.serverExtensions != null)
{
securityParameters.encryptThenMac = TlsExtensionsUtilities.HasEncryptThenMacExtension(state.serverExtensions);
securityParameters.maxFragmentLength = DtlsProtocol.EvaluateMaxFragmentLengthExtension(state.resumedSession, state.clientExtensions, state.serverExtensions, 80);
securityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(state.serverExtensions);
state.allowCertificateStatus = (!state.resumedSession && TlsUtilities.HasExpectedEmptyExtensionData(state.serverExtensions, 5, 80));
state.expectSessionTicket = (!state.resumedSession && TlsUtilities.HasExpectedEmptyExtensionData(state.serverExtensions, 35, 80));
TlsProtocol.WriteExtensions(memoryStream, state.serverExtensions);
}
securityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(state.serverContext, securityParameters.CipherSuite);
securityParameters.verifyDataLength = 12;
return(memoryStream.ToArray());
}
internal virtual DtlsTransport ClientHandshake(ClientHandshakeState state, DtlsRecordLayer recordLayer)
{
SecurityParameters securityParameters = state.clientContext.SecurityParameters;
DtlsReliableHandshake handshake = new DtlsReliableHandshake(state.clientContext, recordLayer);
byte[] clientHelloBody = GenerateClientHello(state, state.client);
handshake.SendMessage(HandshakeType.client_hello, clientHelloBody);
DtlsReliableHandshake.Message serverMessage = handshake.ReceiveMessage();
while (serverMessage.Type == HandshakeType.hello_verify_request)
{
ProtocolVersion recordLayerVersion = recordLayer.ResetDiscoveredPeerVersion();
ProtocolVersion client_version = state.clientContext.ClientVersion;
/*
* RFC 6347 4.2.1 DTLS 1.2 server implementations SHOULD use DTLS version 1.0 regardless of
* the version of TLS that is expected to be negotiated. DTLS 1.2 and 1.0 clients MUST use
* the version solely to indicate packet formatting (which is the same in both DTLS 1.2 and
* 1.0) and not as part of version negotiation.
*/
if (!recordLayerVersion.IsEqualOrEarlierVersionOf(client_version))
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
byte[] cookie = ProcessHelloVerifyRequest(state, serverMessage.Body);
byte[] patched = PatchClientHelloWithCookie(clientHelloBody, cookie);
handshake.ResetHandshakeMessagesDigest();
handshake.SendMessage(HandshakeType.client_hello, patched);
serverMessage = handshake.ReceiveMessage();
}
if (serverMessage.Type == HandshakeType.server_hello)
{
ReportServerVersion(state, recordLayer.DiscoveredPeerVersion);
ProcessServerHello(state, serverMessage.Body);
}
else
{
throw new TlsFatalAlert(AlertDescription.unexpected_message);
}
if (state.maxFragmentLength >= 0)
{
int plainTextLimit = 1 << (8 + state.maxFragmentLength);
recordLayer.SetPlaintextLimit(plainTextLimit);
}
securityParameters.cipherSuite = state.selectedCipherSuite;
securityParameters.compressionAlgorithm = (byte)state.selectedCompressionMethod;
securityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(state.clientContext, state.selectedCipherSuite);
/*
* RFC 5264 7.4.9. Any cipher suite which does not explicitly specify verify_data_length has
* a verify_data_length equal to 12. This includes all existing cipher suites.
*/
securityParameters.verifyDataLength = 12;
handshake.NotifyHelloComplete();
bool resumedSession = state.selectedSessionID.Length > 0 && state.tlsSession != null &&
Arrays.AreEqual(state.selectedSessionID, state.tlsSession.SessionID);
if (resumedSession)
{
if (securityParameters.CipherSuite != state.sessionParameters.CipherSuite ||
securityParameters.CompressionAlgorithm != state.sessionParameters.CompressionAlgorithm)
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
IDictionary sessionServerExtensions = state.sessionParameters.ReadServerExtensions();
securityParameters.extendedMasterSecret = TlsExtensionsUtilities.HasExtendedMasterSecretExtension(sessionServerExtensions);
securityParameters.masterSecret = Arrays.Clone(state.sessionParameters.MasterSecret);
recordLayer.InitPendingEpoch(state.client.GetCipher());
// NOTE: Calculated exclusive of the actual Finished message from the server
byte[] resExpectedServerVerifyData = TlsUtilities.CalculateVerifyData(state.clientContext, ExporterLabel.server_finished,
TlsProtocol.GetCurrentPrfHash(state.clientContext, handshake.HandshakeHash, null));
ProcessFinished(handshake.ReceiveMessageBody(HandshakeType.finished), resExpectedServerVerifyData);
// NOTE: Calculated exclusive of the Finished message itself
byte[] resClientVerifyData = TlsUtilities.CalculateVerifyData(state.clientContext, ExporterLabel.client_finished,
TlsProtocol.GetCurrentPrfHash(state.clientContext, handshake.HandshakeHash, null));
handshake.SendMessage(HandshakeType.finished, resClientVerifyData);
handshake.Finish();
state.clientContext.SetResumableSession(state.tlsSession);
state.client.NotifyHandshakeComplete();
return(new DtlsTransport(recordLayer));
}
InvalidateSession(state);
if (state.selectedSessionID.Length > 0)
{
state.tlsSession = new TlsSessionImpl(state.selectedSessionID, null);
}
serverMessage = handshake.ReceiveMessage();
if (serverMessage.Type == HandshakeType.supplemental_data)
{
ProcessServerSupplementalData(state, serverMessage.Body);
serverMessage = handshake.ReceiveMessage();
}
else
{
state.client.ProcessServerSupplementalData(null);
}
state.keyExchange = state.client.GetKeyExchange();
state.keyExchange.Init(state.clientContext);
Certificate serverCertificate = null;
if (serverMessage.Type == HandshakeType.certificate)
{
serverCertificate = ProcessServerCertificate(state, serverMessage.Body);
serverMessage = handshake.ReceiveMessage();
}
else
{
// Okay, Certificate is optional
state.keyExchange.SkipServerCredentials();
}
// TODO[RFC 3546] Check whether empty certificates is possible, allowed, or excludes CertificateStatus
if (serverCertificate == null || serverCertificate.IsEmpty)
{
state.allowCertificateStatus = false;
}
if (serverMessage.Type == HandshakeType.certificate_status)
{
ProcessCertificateStatus(state, serverMessage.Body);
serverMessage = handshake.ReceiveMessage();
}
else
{
// Okay, CertificateStatus is optional
}
if (serverMessage.Type == HandshakeType.server_key_exchange)
{
ProcessServerKeyExchange(state, serverMessage.Body);
serverMessage = handshake.ReceiveMessage();
}
else
{
// Okay, ServerKeyExchange is optional
state.keyExchange.SkipServerKeyExchange();
}
if (serverMessage.Type == HandshakeType.certificate_request)
{
ProcessCertificateRequest(state, serverMessage.Body);
/*
* TODO Give the client a chance to immediately select the CertificateVerify hash
* algorithm here to avoid tracking the other hash algorithms unnecessarily?
*/
TlsUtilities.TrackHashAlgorithms(handshake.HandshakeHash,
state.certificateRequest.SupportedSignatureAlgorithms);
serverMessage = handshake.ReceiveMessage();
}
else
{
// Okay, CertificateRequest is optional
}
if (serverMessage.Type == HandshakeType.server_hello_done)
{
if (serverMessage.Body.Length != 0)
{
throw new TlsFatalAlert(AlertDescription.decode_error);
}
}
else
{
throw new TlsFatalAlert(AlertDescription.unexpected_message);
}
handshake.HandshakeHash.SealHashAlgorithms();
IList clientSupplementalData = state.client.GetClientSupplementalData();
if (clientSupplementalData != null)
{
byte[] supplementalDataBody = GenerateSupplementalData(clientSupplementalData);
handshake.SendMessage(HandshakeType.supplemental_data, supplementalDataBody);
}
if (state.certificateRequest != null)
{
state.clientCredentials = state.authentication.GetClientCredentials(state.certificateRequest);
/*
* RFC 5246 If no suitable certificate is available, the client MUST send a certificate
* message containing no certificates.
*
* NOTE: In previous RFCs, this was SHOULD instead of MUST.
*/
Certificate clientCertificate = null;
if (state.clientCredentials != null)
{
clientCertificate = state.clientCredentials.Certificate;
}
if (clientCertificate == null)
{
clientCertificate = Certificate.EmptyChain;
}
byte[] certificateBody = GenerateCertificate(clientCertificate);
handshake.SendMessage(HandshakeType.certificate, certificateBody);
}
if (state.clientCredentials != null)
{
state.keyExchange.ProcessClientCredentials(state.clientCredentials);
}
else
{
state.keyExchange.SkipClientCredentials();
}
byte[] clientKeyExchangeBody = GenerateClientKeyExchange(state);
handshake.SendMessage(HandshakeType.client_key_exchange, clientKeyExchangeBody);
TlsHandshakeHash prepareFinishHash = handshake.PrepareToFinish();
securityParameters.sessionHash = TlsProtocol.GetCurrentPrfHash(state.clientContext, prepareFinishHash, null);
TlsProtocol.EstablishMasterSecret(state.clientContext, state.keyExchange);
recordLayer.InitPendingEpoch(state.client.GetCipher());
if (state.clientCredentials != null && state.clientCredentials is TlsSignerCredentials)
{
TlsSignerCredentials signerCredentials = (TlsSignerCredentials)state.clientCredentials;
/*
* RFC 5246 4.7. digitally-signed element needs SignatureAndHashAlgorithm from TLS 1.2
*/
SignatureAndHashAlgorithm signatureAndHashAlgorithm;
byte[] hash;
if (TlsUtilities.IsTlsV12(state.clientContext))
{
signatureAndHashAlgorithm = signerCredentials.SignatureAndHashAlgorithm;
if (signatureAndHashAlgorithm == null)
{
throw new TlsFatalAlert(AlertDescription.internal_error);
}
hash = prepareFinishHash.GetFinalHash(signatureAndHashAlgorithm.Hash);
}
else
{
signatureAndHashAlgorithm = null;
hash = securityParameters.SessionHash;
}
byte[] signature = signerCredentials.GenerateCertificateSignature(hash);
DigitallySigned certificateVerify = new DigitallySigned(signatureAndHashAlgorithm, signature);
byte[] certificateVerifyBody = GenerateCertificateVerify(state, certificateVerify);
handshake.SendMessage(HandshakeType.certificate_verify, certificateVerifyBody);
}
// NOTE: Calculated exclusive of the Finished message itself
byte[] clientVerifyData = TlsUtilities.CalculateVerifyData(state.clientContext, ExporterLabel.client_finished,
TlsProtocol.GetCurrentPrfHash(state.clientContext, handshake.HandshakeHash, null));
handshake.SendMessage(HandshakeType.finished, clientVerifyData);
if (state.expectSessionTicket)
{
serverMessage = handshake.ReceiveMessage();
if (serverMessage.Type == HandshakeType.session_ticket)
{
ProcessNewSessionTicket(state, serverMessage.Body);
}
else
{
throw new TlsFatalAlert(AlertDescription.unexpected_message);
}
}
// NOTE: Calculated exclusive of the actual Finished message from the server
byte[] expectedServerVerifyData = TlsUtilities.CalculateVerifyData(state.clientContext, ExporterLabel.server_finished,
TlsProtocol.GetCurrentPrfHash(state.clientContext, handshake.HandshakeHash, null));
ProcessFinished(handshake.ReceiveMessageBody(HandshakeType.finished), expectedServerVerifyData);
handshake.Finish();
if (state.tlsSession != null)
{
state.sessionParameters = new SessionParameters.Builder()
.SetCipherSuite(securityParameters.cipherSuite)
.SetCompressionAlgorithm(securityParameters.compressionAlgorithm)
.SetMasterSecret(securityParameters.masterSecret)
.SetPeerCertificate(serverCertificate)
.SetPskIdentity(securityParameters.pskIdentity)
.Build();
state.tlsSession = TlsUtilities.ImportSession(state.tlsSession.SessionID, state.sessionParameters);
state.clientContext.SetResumableSession(state.tlsSession);
}
state.client.NotifyHandshakeComplete();
return(new DtlsTransport(recordLayer));
}
protected virtual byte[] GenerateServerHello(ServerHandshakeState state)
{
SecurityParameters securityParameters = state.serverContext.SecurityParameters;
MemoryStream buf = new MemoryStream();
{
ProtocolVersion server_version = state.server.GetServerVersion();
if (!server_version.IsEqualOrEarlierVersionOf(state.serverContext.ClientVersion))
{
throw new TlsFatalAlert(AlertDescription.internal_error);
}
// TODO Read RFCs for guidance on the expected record layer version number
// recordStream.setReadVersion(server_version);
// recordStream.setWriteVersion(server_version);
// recordStream.setRestrictReadVersion(true);
state.serverContext.SetServerVersion(server_version);
TlsUtilities.WriteVersion(state.serverContext.ServerVersion, buf);
}
buf.Write(securityParameters.ServerRandom, 0, securityParameters.ServerRandom.Length);
/*
* The server may return an empty session_id to indicate that the session will not be cached
* and therefore cannot be resumed.
*/
TlsUtilities.WriteOpaque8(TlsUtilities.EmptyBytes, buf);
int selectedCipherSuite = state.server.GetSelectedCipherSuite();
if (!Arrays.Contains(state.offeredCipherSuites, selectedCipherSuite) ||
selectedCipherSuite == CipherSuite.TLS_NULL_WITH_NULL_NULL ||
CipherSuite.IsScsv(selectedCipherSuite) ||
!TlsUtilities.IsValidCipherSuiteForVersion(selectedCipherSuite, state.serverContext.ServerVersion))
{
throw new TlsFatalAlert(AlertDescription.internal_error);
}
ValidateSelectedCipherSuite(selectedCipherSuite, AlertDescription.internal_error);
securityParameters.cipherSuite = selectedCipherSuite;
byte selectedCompressionMethod = state.server.GetSelectedCompressionMethod();
if (!Arrays.Contains(state.offeredCompressionMethods, selectedCompressionMethod))
{
throw new TlsFatalAlert(AlertDescription.internal_error);
}
securityParameters.compressionAlgorithm = selectedCompressionMethod;
TlsUtilities.WriteUint16(selectedCipherSuite, buf);
TlsUtilities.WriteUint8(selectedCompressionMethod, buf);
state.serverExtensions = state.server.GetServerExtensions();
/*
* RFC 5746 3.6. Server Behavior: Initial Handshake
*/
if (state.secure_renegotiation)
{
byte[] renegExtData = TlsUtilities.GetExtensionData(state.serverExtensions, ExtensionType.renegotiation_info);
bool noRenegExt = (null == renegExtData);
if (noRenegExt)
{
/*
* Note that sending a "renegotiation_info" extension in response to a ClientHello
* containing only the SCSV is an explicit exception to the prohibition in RFC 5246,
* Section 7.4.1.4, on the server sending unsolicited extensions and is only allowed
* because the client is signaling its willingness to receive the extension via the
* TLS_EMPTY_RENEGOTIATION_INFO_SCSV SCSV.
*/
/*
* If the secure_renegotiation flag is set to TRUE, the server MUST include an empty
* "renegotiation_info" extension in the ServerHello message.
*/
state.serverExtensions = TlsExtensionsUtilities.EnsureExtensionsInitialised(state.serverExtensions);
state.serverExtensions[ExtensionType.renegotiation_info] = TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes);
}
}
if (securityParameters.extendedMasterSecret)
{
state.serverExtensions = TlsExtensionsUtilities.EnsureExtensionsInitialised(state.serverExtensions);
TlsExtensionsUtilities.AddExtendedMasterSecretExtension(state.serverExtensions);
}
/*
* TODO RFC 3546 2.3 If [...] the older session is resumed, then the server MUST ignore
* extensions appearing in the client hello, and send a server hello containing no
* extensions.
*/
if (state.serverExtensions != null)
{
securityParameters.encryptThenMac = TlsExtensionsUtilities.HasEncryptThenMacExtension(state.serverExtensions);
securityParameters.maxFragmentLength = EvaluateMaxFragmentLengthExtension(state.resumedSession,
state.clientExtensions, state.serverExtensions, AlertDescription.internal_error);
securityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(state.serverExtensions);
/*
* TODO It's surprising that there's no provision to allow a 'fresh' CertificateStatus to be sent in
* a session resumption handshake.
*/
state.allowCertificateStatus = !state.resumedSession &&
TlsUtilities.HasExpectedEmptyExtensionData(state.serverExtensions, ExtensionType.status_request,
AlertDescription.internal_error);
state.expectSessionTicket = !state.resumedSession &&
TlsUtilities.HasExpectedEmptyExtensionData(state.serverExtensions, ExtensionType.session_ticket,
AlertDescription.internal_error);
TlsProtocol.WriteExtensions(buf, state.serverExtensions);
}
securityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(state.serverContext,
securityParameters.CipherSuite);
/*
* RFC 5246 7.4.9. Any cipher suite which does not explicitly specify verify_data_length
* has a verify_data_length equal to 12. This includes all existing cipher suites.
*/
securityParameters.verifyDataLength = 12;
return(buf.ToArray());
}
protected virtual void SendServerHelloMessage()
{
TlsProtocol.HandshakeMessage handshakeMessage = new TlsProtocol.HandshakeMessage(2);
ProtocolVersion serverVersion = this.mTlsServer.GetServerVersion();
if (!serverVersion.IsEqualOrEarlierVersionOf(this.Context.ClientVersion))
{
throw new TlsFatalAlert(80);
}
this.mRecordStream.ReadVersion = serverVersion;
this.mRecordStream.SetWriteVersion(serverVersion);
this.mRecordStream.SetRestrictReadVersion(true);
this.ContextAdmin.SetServerVersion(serverVersion);
TlsUtilities.WriteVersion(serverVersion, handshakeMessage);
handshakeMessage.Write(this.mSecurityParameters.serverRandom);
TlsUtilities.WriteOpaque8(TlsUtilities.EmptyBytes, handshakeMessage);
int selectedCipherSuite = this.mTlsServer.GetSelectedCipherSuite();
if (!Arrays.Contains(this.mOfferedCipherSuites, selectedCipherSuite) || selectedCipherSuite == 0 || CipherSuite.IsScsv(selectedCipherSuite) || !TlsUtilities.IsValidCipherSuiteForVersion(selectedCipherSuite, this.Context.ServerVersion))
{
throw new TlsFatalAlert(80);
}
this.mSecurityParameters.cipherSuite = selectedCipherSuite;
byte selectedCompressionMethod = this.mTlsServer.GetSelectedCompressionMethod();
if (!Arrays.Contains(this.mOfferedCompressionMethods, selectedCompressionMethod))
{
throw new TlsFatalAlert(80);
}
this.mSecurityParameters.compressionAlgorithm = selectedCompressionMethod;
TlsUtilities.WriteUint16(selectedCipherSuite, handshakeMessage);
TlsUtilities.WriteUint8(selectedCompressionMethod, handshakeMessage);
this.mServerExtensions = this.mTlsServer.GetServerExtensions();
if (this.mSecureRenegotiation)
{
byte[] extensionData = TlsUtilities.GetExtensionData(this.mServerExtensions, 65281);
bool flag = null == extensionData;
if (flag)
{
this.mServerExtensions = TlsExtensionsUtilities.EnsureExtensionsInitialised(this.mServerExtensions);
this.mServerExtensions[65281] = TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes);
}
}
if (this.mSecurityParameters.extendedMasterSecret)
{
this.mServerExtensions = TlsExtensionsUtilities.EnsureExtensionsInitialised(this.mServerExtensions);
TlsExtensionsUtilities.AddExtendedMasterSecretExtension(this.mServerExtensions);
}
if (this.mServerExtensions != null)
{
this.mSecurityParameters.encryptThenMac = TlsExtensionsUtilities.HasEncryptThenMacExtension(this.mServerExtensions);
this.mSecurityParameters.maxFragmentLength = this.ProcessMaxFragmentLengthExtension(this.mClientExtensions, this.mServerExtensions, 80);
this.mSecurityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(this.mServerExtensions);
this.mAllowCertificateStatus = (!this.mResumedSession && TlsUtilities.HasExpectedEmptyExtensionData(this.mServerExtensions, 5, 80));
this.mExpectSessionTicket = (!this.mResumedSession && TlsUtilities.HasExpectedEmptyExtensionData(this.mServerExtensions, 35, 80));
TlsProtocol.WriteExtensions(handshakeMessage, this.mServerExtensions);
}
this.mSecurityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(this.Context, this.mSecurityParameters.CipherSuite);
this.mSecurityParameters.verifyDataLength = 12;
this.ApplyMaxFragmentLengthExtension();
handshakeMessage.WriteToRecordStream(this);
}
protected virtual void ProcessServerHello(ClientHandshakeState state, byte[] body)
{
SecurityParameters securityParameters = state.clientContext.SecurityParameters;
MemoryStream buf = new MemoryStream(body, false);
{
ProtocolVersion server_version = TlsUtilities.ReadVersion(buf);
ReportServerVersion(state, server_version);
}
securityParameters.serverRandom = TlsUtilities.ReadFully(32, buf);
state.selectedSessionID = TlsUtilities.ReadOpaque8(buf);
if (state.selectedSessionID.Length > 32)
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
state.client.NotifySessionID(state.selectedSessionID);
state.resumedSession = state.selectedSessionID.Length > 0 && state.tlsSession != null &&
Arrays.AreEqual(state.selectedSessionID, state.tlsSession.SessionID);
int selectedCipherSuite = TlsUtilities.ReadUint16(buf);
if (!Arrays.Contains(state.offeredCipherSuites, selectedCipherSuite) ||
selectedCipherSuite == CipherSuite.TLS_NULL_WITH_NULL_NULL ||
CipherSuite.IsScsv(selectedCipherSuite) ||
!TlsUtilities.IsValidCipherSuiteForVersion(selectedCipherSuite, state.clientContext.ServerVersion))
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
ValidateSelectedCipherSuite(selectedCipherSuite, AlertDescription.illegal_parameter);
state.client.NotifySelectedCipherSuite(selectedCipherSuite);
byte selectedCompressionMethod = TlsUtilities.ReadUint8(buf);
if (!Arrays.Contains(state.offeredCompressionMethods, selectedCompressionMethod))
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
state.client.NotifySelectedCompressionMethod(selectedCompressionMethod);
/*
* RFC3546 2.2 The extended server hello message format MAY be sent in place of the server
* hello message when the client has requested extended functionality via the extended
* client hello message specified in Section 2.1. ... Note that the extended server hello
* message is only sent in response to an extended client hello message. This prevents the
* possibility that the extended server hello message could "break" existing TLS 1.0
* clients.
*/
/*
* TODO RFC 3546 2.3 If [...] the older session is resumed, then the server MUST ignore
* extensions appearing in the client hello, and send a server hello containing no
* extensions.
*/
// Integer -> byte[]
state.serverExtensions = TlsProtocol.ReadExtensions(buf);
/*
* RFC 3546 2.2 Note that the extended server hello message is only sent in response to an
* extended client hello message. However, see RFC 5746 exception below. We always include
* the SCSV, so an Extended Server Hello is always allowed.
*/
if (state.serverExtensions != null)
{
foreach (int extType in state.serverExtensions.Keys)
{
/*
* RFC 5746 3.6. Note that sending a "renegotiation_info" extension in response to a
* ClientHello containing only the SCSV is an explicit exception to the prohibition
* in RFC 5246, Section 7.4.1.4, on the server sending unsolicited extensions and is
* only allowed because the client is signaling its willingness to receive the
* extension via the TLS_EMPTY_RENEGOTIATION_INFO_SCSV SCSV.
*/
if (extType == ExtensionType.renegotiation_info)
{
continue;
}
/*
* RFC 5246 7.4.1.4 An extension type MUST NOT appear in the ServerHello unless the
* same extension type appeared in the corresponding ClientHello. If a client
* receives an extension type in ServerHello that it did not request in the
* associated ClientHello, it MUST abort the handshake with an unsupported_extension
* fatal alert.
*/
if (null == TlsUtilities.GetExtensionData(state.clientExtensions, extType))
{
throw new TlsFatalAlert(AlertDescription.unsupported_extension);
}
/*
* RFC 3546 2.3. If [...] the older session is resumed, then the server MUST ignore
* extensions appearing in the client hello, and send a server hello containing no
* extensions[.]
*/
if (state.resumedSession)
{
// TODO[compat-gnutls] GnuTLS test server sends server extensions e.g. ec_point_formats
// TODO[compat-openssl] OpenSSL test server sends server extensions e.g. ec_point_formats
// TODO[compat-polarssl] PolarSSL test server sends server extensions e.g. ec_point_formats
//throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
}
}
/*
* RFC 5746 3.4. Client Behavior: Initial Handshake
*/
{
/*
* When a ServerHello is received, the client MUST check if it includes the
* "renegotiation_info" extension:
*/
byte[] renegExtData = TlsUtilities.GetExtensionData(state.serverExtensions, ExtensionType.renegotiation_info);
if (renegExtData != null)
{
/*
* If the extension is present, set the secure_renegotiation flag to TRUE. The
* client MUST then verify that the length of the "renegotiated_connection"
* field is zero, and if it is not, MUST abort the handshake (by sending a fatal
* handshake_failure alert).
*/
state.secure_renegotiation = true;
if (!Arrays.ConstantTimeAreEqual(renegExtData, TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes)))
{
throw new TlsFatalAlert(AlertDescription.handshake_failure);
}
}
}
// TODO[compat-gnutls] GnuTLS test server fails to send renegotiation_info extension when resuming
state.client.NotifySecureRenegotiation(state.secure_renegotiation);
IDictionary sessionClientExtensions = state.clientExtensions, sessionServerExtensions = state.serverExtensions;
if (state.resumedSession)
{
if (selectedCipherSuite != state.sessionParameters.CipherSuite ||
selectedCompressionMethod != state.sessionParameters.CompressionAlgorithm)
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
sessionClientExtensions = null;
sessionServerExtensions = state.sessionParameters.ReadServerExtensions();
}
securityParameters.cipherSuite = selectedCipherSuite;
securityParameters.compressionAlgorithm = selectedCompressionMethod;
if (sessionServerExtensions != null)
{
{
/*
* RFC 7366 3. If a server receives an encrypt-then-MAC request extension from a client
* and then selects a stream or Authenticated Encryption with Associated Data (AEAD)
* ciphersuite, it MUST NOT send an encrypt-then-MAC response extension back to the
* client.
*/
bool serverSentEncryptThenMAC = TlsExtensionsUtilities.HasEncryptThenMacExtension(sessionServerExtensions);
if (serverSentEncryptThenMAC && !TlsUtilities.IsBlockCipherSuite(securityParameters.CipherSuite))
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
securityParameters.encryptThenMac = serverSentEncryptThenMAC;
}
securityParameters.extendedMasterSecret = TlsExtensionsUtilities.HasExtendedMasterSecretExtension(sessionServerExtensions);
securityParameters.maxFragmentLength = EvaluateMaxFragmentLengthExtension(state.resumedSession,
sessionClientExtensions, sessionServerExtensions, AlertDescription.illegal_parameter);
securityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(sessionServerExtensions);
/*
* TODO It's surprising that there's no provision to allow a 'fresh' CertificateStatus to be
* sent in a session resumption handshake.
*/
state.allowCertificateStatus = !state.resumedSession &&
TlsUtilities.HasExpectedEmptyExtensionData(sessionServerExtensions, ExtensionType.status_request,
AlertDescription.illegal_parameter);
state.expectSessionTicket = !state.resumedSession &&
TlsUtilities.HasExpectedEmptyExtensionData(sessionServerExtensions, ExtensionType.session_ticket,
AlertDescription.illegal_parameter);
}
/*
* TODO[session-hash]
*
* draft-ietf-tls-session-hash-04 4. Clients and servers SHOULD NOT accept handshakes
* that do not use the extended master secret [..]. (and see 5.2, 5.3)
*/
if (sessionClientExtensions != null)
{
state.client.ProcessServerExtensions(sessionServerExtensions);
}
securityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(state.clientContext,
securityParameters.CipherSuite);
/*
* RFC 5264 7.4.9. Any cipher suite which does not explicitly specify verify_data_length has
* a verify_data_length equal to 12. This includes all existing cipher suites.
*/
securityParameters.verifyDataLength = 12;
}
protected virtual byte[] GenerateServerHello(ServerHandshakeState state)
{
//IL_000c: Unknown result type (might be due to invalid IL or missing references)
//IL_0012: Expected O, but got Unknown
SecurityParameters securityParameters = state.serverContext.SecurityParameters;
MemoryStream val = new MemoryStream();
ProtocolVersion serverVersion = state.server.GetServerVersion();
if (!serverVersion.IsEqualOrEarlierVersionOf(state.serverContext.ClientVersion))
{
throw new TlsFatalAlert(80);
}
state.serverContext.SetServerVersion(serverVersion);
TlsUtilities.WriteVersion(state.serverContext.ServerVersion, (Stream)(object)val);
((Stream)val).Write(securityParameters.ServerRandom, 0, securityParameters.ServerRandom.Length);
TlsUtilities.WriteOpaque8(TlsUtilities.EmptyBytes, (Stream)(object)val);
int selectedCipherSuite = state.server.GetSelectedCipherSuite();
if (!Arrays.Contains(state.offeredCipherSuites, selectedCipherSuite) || selectedCipherSuite == 0 || CipherSuite.IsScsv(selectedCipherSuite) || !TlsUtilities.IsValidCipherSuiteForVersion(selectedCipherSuite, state.serverContext.ServerVersion))
{
throw new TlsFatalAlert(80);
}
DtlsProtocol.ValidateSelectedCipherSuite(selectedCipherSuite, 80);
securityParameters.cipherSuite = selectedCipherSuite;
byte selectedCompressionMethod = state.server.GetSelectedCompressionMethod();
if (!Arrays.Contains(state.offeredCompressionMethods, selectedCompressionMethod))
{
throw new TlsFatalAlert(80);
}
securityParameters.compressionAlgorithm = selectedCompressionMethod;
TlsUtilities.WriteUint16(selectedCipherSuite, (Stream)(object)val);
TlsUtilities.WriteUint8(selectedCompressionMethod, (Stream)(object)val);
state.serverExtensions = state.server.GetServerExtensions();
if (state.secure_renegotiation)
{
byte[] extensionData = TlsUtilities.GetExtensionData(state.serverExtensions, 65281);
if (null == extensionData)
{
state.serverExtensions = TlsExtensionsUtilities.EnsureExtensionsInitialised(state.serverExtensions);
state.serverExtensions.set_Item((object)65281, (object)TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes));
}
}
if (securityParameters.extendedMasterSecret)
{
state.serverExtensions = TlsExtensionsUtilities.EnsureExtensionsInitialised(state.serverExtensions);
TlsExtensionsUtilities.AddExtendedMasterSecretExtension(state.serverExtensions);
}
if (state.serverExtensions != null)
{
securityParameters.encryptThenMac = TlsExtensionsUtilities.HasEncryptThenMacExtension(state.serverExtensions);
securityParameters.maxFragmentLength = DtlsProtocol.EvaluateMaxFragmentLengthExtension(state.resumedSession, state.clientExtensions, state.serverExtensions, 80);
securityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(state.serverExtensions);
state.allowCertificateStatus = !state.resumedSession && TlsUtilities.HasExpectedEmptyExtensionData(state.serverExtensions, 5, 80);
state.expectSessionTicket = !state.resumedSession && TlsUtilities.HasExpectedEmptyExtensionData(state.serverExtensions, 35, 80);
TlsProtocol.WriteExtensions((Stream)(object)val, state.serverExtensions);
}
securityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(state.serverContext, securityParameters.CipherSuite);
securityParameters.verifyDataLength = 12;
return(val.ToArray());
}
protected virtual void ProcessServerHello(DtlsClientProtocol.ClientHandshakeState state, byte[] body)
{
SecurityParameters securityParameters = state.clientContext.SecurityParameters;
MemoryStream input = new MemoryStream(body, false);
ProtocolVersion server_version = TlsUtilities.ReadVersion(input);
this.ReportServerVersion(state, server_version);
securityParameters.serverRandom = TlsUtilities.ReadFully(32, input);
state.selectedSessionID = TlsUtilities.ReadOpaque8(input);
if (state.selectedSessionID.Length > 32)
{
throw new TlsFatalAlert(47);
}
state.client.NotifySessionID(state.selectedSessionID);
state.resumedSession = (state.selectedSessionID.Length > 0 && state.tlsSession != null && Arrays.AreEqual(state.selectedSessionID, state.tlsSession.SessionID));
int num = TlsUtilities.ReadUint16(input);
if (!Arrays.Contains(state.offeredCipherSuites, num) || num == 0 || CipherSuite.IsScsv(num) || !TlsUtilities.IsValidCipherSuiteForVersion(num, state.clientContext.ServerVersion))
{
throw new TlsFatalAlert(47);
}
DtlsProtocol.ValidateSelectedCipherSuite(num, 47);
state.client.NotifySelectedCipherSuite(num);
byte b = TlsUtilities.ReadUint8(input);
if (!Arrays.Contains(state.offeredCompressionMethods, b))
{
throw new TlsFatalAlert(47);
}
state.client.NotifySelectedCompressionMethod(b);
state.serverExtensions = TlsProtocol.ReadExtensions(input);
if (state.serverExtensions != null)
{
foreach (int num2 in state.serverExtensions.Keys)
{
if (num2 != 65281)
{
if (TlsUtilities.GetExtensionData(state.clientExtensions, num2) == null)
{
throw new TlsFatalAlert(110);
}
bool arg_16B_0 = state.resumedSession;
}
}
}
byte[] extensionData = TlsUtilities.GetExtensionData(state.serverExtensions, 65281);
if (extensionData != null)
{
state.secure_renegotiation = true;
if (!Arrays.ConstantTimeAreEqual(extensionData, TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes)))
{
throw new TlsFatalAlert(40);
}
}
state.client.NotifySecureRenegotiation(state.secure_renegotiation);
IDictionary dictionary = state.clientExtensions;
IDictionary dictionary2 = state.serverExtensions;
if (state.resumedSession)
{
if (num != state.sessionParameters.CipherSuite || b != state.sessionParameters.CompressionAlgorithm)
{
throw new TlsFatalAlert(47);
}
dictionary = null;
dictionary2 = state.sessionParameters.ReadServerExtensions();
}
securityParameters.cipherSuite = num;
securityParameters.compressionAlgorithm = b;
if (dictionary2 != null)
{
bool flag = TlsExtensionsUtilities.HasEncryptThenMacExtension(dictionary2);
if (flag && !TlsUtilities.IsBlockCipherSuite(securityParameters.CipherSuite))
{
throw new TlsFatalAlert(47);
}
securityParameters.encryptThenMac = flag;
securityParameters.extendedMasterSecret = TlsExtensionsUtilities.HasExtendedMasterSecretExtension(dictionary2);
securityParameters.maxFragmentLength = DtlsProtocol.EvaluateMaxFragmentLengthExtension(state.resumedSession, dictionary, dictionary2, 47);
securityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(dictionary2);
state.allowCertificateStatus = (!state.resumedSession && TlsUtilities.HasExpectedEmptyExtensionData(dictionary2, 5, 47));
state.expectSessionTicket = (!state.resumedSession && TlsUtilities.HasExpectedEmptyExtensionData(dictionary2, 35, 47));
}
if (dictionary != null)
{
state.client.ProcessServerExtensions(dictionary2);
}
securityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(state.clientContext, securityParameters.CipherSuite);
securityParameters.verifyDataLength = 12;
}
protected virtual void ProcessServerHello(ClientHandshakeState state, byte[] body)
{
//IL_000e: Unknown result type (might be due to invalid IL or missing references)
//IL_0014: Expected O, but got Unknown
SecurityParameters securityParameters = state.clientContext.SecurityParameters;
MemoryStream input = new MemoryStream(body, false);
ProtocolVersion server_version = TlsUtilities.ReadVersion((Stream)(object)input);
ReportServerVersion(state, server_version);
securityParameters.serverRandom = TlsUtilities.ReadFully(32, (Stream)(object)input);
state.selectedSessionID = TlsUtilities.ReadOpaque8((Stream)(object)input);
if (state.selectedSessionID.Length > 32)
{
throw new TlsFatalAlert(47);
}
state.client.NotifySessionID(state.selectedSessionID);
state.resumedSession = state.selectedSessionID.Length > 0 && state.tlsSession != null && Arrays.AreEqual(state.selectedSessionID, state.tlsSession.SessionID);
int num = TlsUtilities.ReadUint16((Stream)(object)input);
if (!Arrays.Contains(state.offeredCipherSuites, num) || num == 0 || CipherSuite.IsScsv(num) || !TlsUtilities.IsValidCipherSuiteForVersion(num, state.clientContext.ServerVersion))
{
throw new TlsFatalAlert(47);
}
DtlsProtocol.ValidateSelectedCipherSuite(num, 47);
state.client.NotifySelectedCipherSuite(num);
byte b = TlsUtilities.ReadUint8((Stream)(object)input);
if (!Arrays.Contains(state.offeredCompressionMethods, b))
{
throw new TlsFatalAlert(47);
}
state.client.NotifySelectedCompressionMethod(b);
state.serverExtensions = TlsProtocol.ReadExtensions(input);
if (state.serverExtensions != null)
{
{
global::System.Collections.IEnumerator enumerator = ((global::System.Collections.IEnumerable)state.serverExtensions.get_Keys()).GetEnumerator();
try
{
while (enumerator.MoveNext())
{
int num2 = (int)enumerator.get_Current();
if (num2 != 65281)
{
if (TlsUtilities.GetExtensionData(state.clientExtensions, num2) == null)
{
throw new TlsFatalAlert(110);
}
_ = state.resumedSession;
}
}
}
finally
{
global::System.IDisposable disposable = enumerator as global::System.IDisposable;
if (disposable != null)
{
disposable.Dispose();
}
}
}
}
byte[] extensionData = TlsUtilities.GetExtensionData(state.serverExtensions, 65281);
if (extensionData != null)
{
state.secure_renegotiation = true;
if (!Arrays.ConstantTimeAreEqual(extensionData, TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes)))
{
throw new TlsFatalAlert(40);
}
}
state.client.NotifySecureRenegotiation(state.secure_renegotiation);
IDictionary val = state.clientExtensions;
IDictionary val2 = state.serverExtensions;
if (state.resumedSession)
{
if (num != state.sessionParameters.CipherSuite || b != state.sessionParameters.CompressionAlgorithm)
{
throw new TlsFatalAlert(47);
}
val = null;
val2 = state.sessionParameters.ReadServerExtensions();
}
securityParameters.cipherSuite = num;
securityParameters.compressionAlgorithm = b;
if (val2 != null)
{
bool flag = TlsExtensionsUtilities.HasEncryptThenMacExtension(val2);
if (flag && !TlsUtilities.IsBlockCipherSuite(securityParameters.CipherSuite))
{
throw new TlsFatalAlert(47);
}
securityParameters.encryptThenMac = flag;
securityParameters.extendedMasterSecret = TlsExtensionsUtilities.HasExtendedMasterSecretExtension(val2);
securityParameters.maxFragmentLength = DtlsProtocol.EvaluateMaxFragmentLengthExtension(state.resumedSession, val, val2, 47);
securityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(val2);
state.allowCertificateStatus = !state.resumedSession && TlsUtilities.HasExpectedEmptyExtensionData(val2, 5, 47);
state.expectSessionTicket = !state.resumedSession && TlsUtilities.HasExpectedEmptyExtensionData(val2, 35, 47);
}
if (val != null)
{
state.client.ProcessServerExtensions(val2);
}
securityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(state.clientContext, securityParameters.CipherSuite);
securityParameters.verifyDataLength = 12;
}
protected virtual void ReceiveServerHelloMessage(MemoryStream buf)
{
ProtocolVersion protocolVersion = TlsUtilities.ReadVersion((Stream)(object)buf);
if (protocolVersion.IsDtls)
{
throw new TlsFatalAlert(47);
}
if (!protocolVersion.Equals(mRecordStream.ReadVersion))
{
throw new TlsFatalAlert(47);
}
ProtocolVersion clientVersion = Context.ClientVersion;
if (!protocolVersion.IsEqualOrEarlierVersionOf(clientVersion))
{
throw new TlsFatalAlert(47);
}
mRecordStream.SetWriteVersion(protocolVersion);
ContextAdmin.SetServerVersion(protocolVersion);
mTlsClient.NotifyServerVersion(protocolVersion);
mSecurityParameters.serverRandom = TlsUtilities.ReadFully(32, (Stream)(object)buf);
mSelectedSessionID = TlsUtilities.ReadOpaque8((Stream)(object)buf);
if (mSelectedSessionID.Length > 32)
{
throw new TlsFatalAlert(47);
}
mTlsClient.NotifySessionID(mSelectedSessionID);
mResumedSession = mSelectedSessionID.Length > 0 && mTlsSession != null && Arrays.AreEqual(mSelectedSessionID, mTlsSession.SessionID);
int num = TlsUtilities.ReadUint16((Stream)(object)buf);
if (!Arrays.Contains(mOfferedCipherSuites, num) || num == 0 || CipherSuite.IsScsv(num) || !TlsUtilities.IsValidCipherSuiteForVersion(num, Context.ServerVersion))
{
throw new TlsFatalAlert(47);
}
mTlsClient.NotifySelectedCipherSuite(num);
byte b = TlsUtilities.ReadUint8((Stream)(object)buf);
if (!Arrays.Contains(mOfferedCompressionMethods, b))
{
throw new TlsFatalAlert(47);
}
mTlsClient.NotifySelectedCompressionMethod(b);
mServerExtensions = TlsProtocol.ReadExtensions(buf);
if (mServerExtensions != null)
{
{
global::System.Collections.IEnumerator enumerator = ((global::System.Collections.IEnumerable)mServerExtensions.get_Keys()).GetEnumerator();
try
{
while (enumerator.MoveNext())
{
int num2 = (int)enumerator.get_Current();
if (num2 != 65281)
{
if (TlsUtilities.GetExtensionData(mClientExtensions, num2) == null)
{
throw new TlsFatalAlert(110);
}
_ = mResumedSession;
}
}
}
finally
{
global::System.IDisposable disposable = enumerator as global::System.IDisposable;
if (disposable != null)
{
disposable.Dispose();
}
}
}
}
byte[] extensionData = TlsUtilities.GetExtensionData(mServerExtensions, 65281);
if (extensionData != null)
{
mSecureRenegotiation = true;
if (!Arrays.ConstantTimeAreEqual(extensionData, TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes)))
{
throw new TlsFatalAlert(40);
}
}
mTlsClient.NotifySecureRenegotiation(mSecureRenegotiation);
IDictionary val = mClientExtensions;
IDictionary val2 = mServerExtensions;
if (mResumedSession)
{
if (num != mSessionParameters.CipherSuite || b != mSessionParameters.CompressionAlgorithm)
{
throw new TlsFatalAlert(47);
}
val = null;
val2 = mSessionParameters.ReadServerExtensions();
}
mSecurityParameters.cipherSuite = num;
mSecurityParameters.compressionAlgorithm = b;
if (val2 != null)
{
bool flag = TlsExtensionsUtilities.HasEncryptThenMacExtension(val2);
if (flag && !TlsUtilities.IsBlockCipherSuite(num))
{
throw new TlsFatalAlert(47);
}
mSecurityParameters.encryptThenMac = flag;
mSecurityParameters.extendedMasterSecret = TlsExtensionsUtilities.HasExtendedMasterSecretExtension(val2);
mSecurityParameters.maxFragmentLength = ProcessMaxFragmentLengthExtension(val, val2, 47);
mSecurityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(val2);
mAllowCertificateStatus = !mResumedSession && TlsUtilities.HasExpectedEmptyExtensionData(val2, 5, 47);
mExpectSessionTicket = !mResumedSession && TlsUtilities.HasExpectedEmptyExtensionData(val2, 35, 47);
}
if (val != null)
{
mTlsClient.ProcessServerExtensions(val2);
}
mSecurityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(Context, mSecurityParameters.CipherSuite);
mSecurityParameters.verifyDataLength = 12;
}
internal virtual DtlsTransport ServerHandshake(ServerHandshakeState state, DtlsRecordLayer recordLayer)
{
SecurityParameters securityParameters = state.serverContext.SecurityParameters;
DtlsReliableHandshake handshake = new DtlsReliableHandshake(state.serverContext, recordLayer);
DtlsReliableHandshake.Message clientMessage = handshake.ReceiveMessage();
{
// NOTE: After receiving a record from the client, we discover the record layer version
ProtocolVersion client_version = recordLayer.DiscoveredPeerVersion;
// TODO Read RFCs for guidance on the expected record layer version number
state.serverContext.SetClientVersion(client_version);
}
if (clientMessage.Type == HandshakeType.client_hello)
{
ProcessClientHello(state, clientMessage.Body);
}
else
{
throw new TlsFatalAlert(AlertDescription.unexpected_message);
}
{
byte[] serverHelloBody = GenerateServerHello(state);
if (state.maxFragmentLength >= 0)
{
int plainTextLimit = 1 << (8 + state.maxFragmentLength);
recordLayer.SetPlaintextLimit(plainTextLimit);
}
securityParameters.cipherSuite = state.selectedCipherSuite;
securityParameters.compressionAlgorithm = (byte)state.selectedCompressionMethod;
securityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(state.serverContext,
state.selectedCipherSuite);
/*
* RFC 5264 7.4.9. Any cipher suite which does not explicitly specify verify_data_length
* has a verify_data_length equal to 12. This includes all existing cipher suites.
*/
securityParameters.verifyDataLength = 12;
handshake.SendMessage(HandshakeType.server_hello, serverHelloBody);
}
handshake.NotifyHelloComplete();
IList serverSupplementalData = state.server.GetServerSupplementalData();
if (serverSupplementalData != null)
{
byte[] supplementalDataBody = GenerateSupplementalData(serverSupplementalData);
handshake.SendMessage(HandshakeType.supplemental_data, supplementalDataBody);
}
state.keyExchange = state.server.GetKeyExchange();
state.keyExchange.Init(state.serverContext);
state.serverCredentials = state.server.GetCredentials();
Certificate serverCertificate = null;
if (state.serverCredentials == null)
{
state.keyExchange.SkipServerCredentials();
}
else
{
state.keyExchange.ProcessServerCredentials(state.serverCredentials);
serverCertificate = state.serverCredentials.Certificate;
byte[] certificateBody = GenerateCertificate(serverCertificate);
handshake.SendMessage(HandshakeType.certificate, certificateBody);
}
// TODO[RFC 3546] Check whether empty certificates is possible, allowed, or excludes CertificateStatus
if (serverCertificate == null || serverCertificate.IsEmpty)
{
state.allowCertificateStatus = false;
}
if (state.allowCertificateStatus)
{
CertificateStatus certificateStatus = state.server.GetCertificateStatus();
if (certificateStatus != null)
{
byte[] certificateStatusBody = GenerateCertificateStatus(state, certificateStatus);
handshake.SendMessage(HandshakeType.certificate_status, certificateStatusBody);
}
}
byte[] serverKeyExchange = state.keyExchange.GenerateServerKeyExchange();
if (serverKeyExchange != null)
{
handshake.SendMessage(HandshakeType.server_key_exchange, serverKeyExchange);
}
if (state.serverCredentials != null)
{
state.certificateRequest = state.server.GetCertificateRequest();
if (state.certificateRequest != null)
{
state.keyExchange.ValidateCertificateRequest(state.certificateRequest);
byte[] certificateRequestBody = GenerateCertificateRequest(state, state.certificateRequest);
handshake.SendMessage(HandshakeType.certificate_request, certificateRequestBody);
TlsUtilities.TrackHashAlgorithms(handshake.HandshakeHash,
state.certificateRequest.SupportedSignatureAlgorithms);
}
}
handshake.SendMessage(HandshakeType.server_hello_done, TlsUtilities.EmptyBytes);
handshake.HandshakeHash.SealHashAlgorithms();
clientMessage = handshake.ReceiveMessage();
if (clientMessage.Type == HandshakeType.supplemental_data)
{
ProcessClientSupplementalData(state, clientMessage.Body);
clientMessage = handshake.ReceiveMessage();
}
else
{
state.server.ProcessClientSupplementalData(null);
}
if (state.certificateRequest == null)
{
state.keyExchange.SkipClientCredentials();
}
else
{
if (clientMessage.Type == HandshakeType.certificate)
{
ProcessClientCertificate(state, clientMessage.Body);
clientMessage = handshake.ReceiveMessage();
}
else
{
if (TlsUtilities.IsTlsV12(state.serverContext))
{
/*
* RFC 5246 If no suitable certificate is available, the client MUST send a
* certificate message containing no certificates.
*
* NOTE: In previous RFCs, this was SHOULD instead of MUST.
*/
throw new TlsFatalAlert(AlertDescription.unexpected_message);
}
NotifyClientCertificate(state, Certificate.EmptyChain);
}
}
if (clientMessage.Type == HandshakeType.client_key_exchange)
{
ProcessClientKeyExchange(state, clientMessage.Body);
}
else
{
throw new TlsFatalAlert(AlertDescription.unexpected_message);
}
TlsHandshakeHash prepareFinishHash = handshake.PrepareToFinish();
securityParameters.sessionHash = TlsProtocol.GetCurrentPrfHash(state.serverContext, prepareFinishHash, null);
TlsProtocol.EstablishMasterSecret(state.serverContext, state.keyExchange);
recordLayer.InitPendingEpoch(state.server.GetCipher());
/*
* RFC 5246 7.4.8 This message is only sent following a client certificate that has signing
* capability (i.e., all certificates except those containing fixed Diffie-Hellman
* parameters).
*/
if (ExpectCertificateVerifyMessage(state))
{
byte[] certificateVerifyBody = handshake.ReceiveMessageBody(HandshakeType.certificate_verify);
ProcessCertificateVerify(state, certificateVerifyBody, prepareFinishHash);
}
// NOTE: Calculated exclusive of the actual Finished message from the client
byte[] expectedClientVerifyData = TlsUtilities.CalculateVerifyData(state.serverContext, ExporterLabel.client_finished,
TlsProtocol.GetCurrentPrfHash(state.serverContext, handshake.HandshakeHash, null));
ProcessFinished(handshake.ReceiveMessageBody(HandshakeType.finished), expectedClientVerifyData);
if (state.expectSessionTicket)
{
NewSessionTicket newSessionTicket = state.server.GetNewSessionTicket();
byte[] newSessionTicketBody = GenerateNewSessionTicket(state, newSessionTicket);
handshake.SendMessage(HandshakeType.session_ticket, newSessionTicketBody);
}
// NOTE: Calculated exclusive of the Finished message itself
byte[] serverVerifyData = TlsUtilities.CalculateVerifyData(state.serverContext, ExporterLabel.server_finished,
TlsProtocol.GetCurrentPrfHash(state.serverContext, handshake.HandshakeHash, null));
handshake.SendMessage(HandshakeType.finished, serverVerifyData);
handshake.Finish();
state.server.NotifyHandshakeComplete();
return(new DtlsTransport(recordLayer));
}
protected virtual void ReceiveServerHelloMessage(MemoryStream buf)
{
ProtocolVersion protocolVersion = TlsUtilities.ReadVersion(buf);
if (protocolVersion.IsDtls)
{
throw new TlsFatalAlert(47);
}
if (!protocolVersion.Equals(mRecordStream.ReadVersion))
{
throw new TlsFatalAlert(47);
}
ProtocolVersion clientVersion = Context.ClientVersion;
if (!protocolVersion.IsEqualOrEarlierVersionOf(clientVersion))
{
throw new TlsFatalAlert(47);
}
mRecordStream.SetWriteVersion(protocolVersion);
ContextAdmin.SetServerVersion(protocolVersion);
mTlsClient.NotifyServerVersion(protocolVersion);
mSecurityParameters.serverRandom = TlsUtilities.ReadFully(32, buf);
mSelectedSessionID = TlsUtilities.ReadOpaque8(buf);
if (mSelectedSessionID.Length > 32)
{
throw new TlsFatalAlert(47);
}
mTlsClient.NotifySessionID(mSelectedSessionID);
mResumedSession = (mSelectedSessionID.Length > 0 && mTlsSession != null && Arrays.AreEqual(mSelectedSessionID, mTlsSession.SessionID));
int num = TlsUtilities.ReadUint16(buf);
if (!Arrays.Contains(mOfferedCipherSuites, num) || num == 0 || CipherSuite.IsScsv(num) || !TlsUtilities.IsValidCipherSuiteForVersion(num, Context.ServerVersion))
{
throw new TlsFatalAlert(47);
}
mTlsClient.NotifySelectedCipherSuite(num);
byte b = TlsUtilities.ReadUint8(buf);
if (!Arrays.Contains(mOfferedCompressionMethods, b))
{
throw new TlsFatalAlert(47);
}
mTlsClient.NotifySelectedCompressionMethod(b);
mServerExtensions = TlsProtocol.ReadExtensions(buf);
if (mServerExtensions != null)
{
foreach (int key in mServerExtensions.Keys)
{
if (key != 65281)
{
if (TlsUtilities.GetExtensionData(mClientExtensions, key) == null)
{
throw new TlsFatalAlert(110);
}
if (!mResumedSession)
{
}
}
}
}
byte[] extensionData = TlsUtilities.GetExtensionData(mServerExtensions, 65281);
if (extensionData != null)
{
mSecureRenegotiation = true;
if (!Arrays.ConstantTimeAreEqual(extensionData, TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes)))
{
throw new TlsFatalAlert(40);
}
}
mTlsClient.NotifySecureRenegotiation(mSecureRenegotiation);
IDictionary dictionary = mClientExtensions;
IDictionary dictionary2 = mServerExtensions;
if (mResumedSession)
{
if (num != mSessionParameters.CipherSuite || b != mSessionParameters.CompressionAlgorithm)
{
throw new TlsFatalAlert(47);
}
dictionary = null;
dictionary2 = mSessionParameters.ReadServerExtensions();
}
mSecurityParameters.cipherSuite = num;
mSecurityParameters.compressionAlgorithm = b;
if (dictionary2 != null)
{
bool flag = TlsExtensionsUtilities.HasEncryptThenMacExtension(dictionary2);
if (flag && !TlsUtilities.IsBlockCipherSuite(num))
{
throw new TlsFatalAlert(47);
}
mSecurityParameters.encryptThenMac = flag;
mSecurityParameters.extendedMasterSecret = TlsExtensionsUtilities.HasExtendedMasterSecretExtension(dictionary2);
mSecurityParameters.maxFragmentLength = ProcessMaxFragmentLengthExtension(dictionary, dictionary2, 47);
mSecurityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(dictionary2);
mAllowCertificateStatus = (!mResumedSession && TlsUtilities.HasExpectedEmptyExtensionData(dictionary2, 5, 47));
mExpectSessionTicket = (!mResumedSession && TlsUtilities.HasExpectedEmptyExtensionData(dictionary2, 35, 47));
}
if (dictionary != null)
{
mTlsClient.ProcessServerExtensions(dictionary2);
}
mSecurityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(Context, mSecurityParameters.CipherSuite);
mSecurityParameters.verifyDataLength = 12;
}
protected virtual void ReceiveServerHelloMessage(MemoryStream buf)
{
ProtocolVersion writeVersion = TlsUtilities.ReadVersion(buf);
if (writeVersion.IsDtls)
{
throw new TlsFatalAlert(0x2f);
}
if (!writeVersion.Equals(base.mRecordStream.ReadVersion))
{
throw new TlsFatalAlert(0x2f);
}
ProtocolVersion clientVersion = this.Context.ClientVersion;
if (!writeVersion.IsEqualOrEarlierVersionOf(clientVersion))
{
throw new TlsFatalAlert(0x2f);
}
base.mRecordStream.SetWriteVersion(writeVersion);
this.ContextAdmin.SetServerVersion(writeVersion);
this.mTlsClient.NotifyServerVersion(writeVersion);
base.mSecurityParameters.serverRandom = TlsUtilities.ReadFully(0x20, buf);
this.mSelectedSessionID = TlsUtilities.ReadOpaque8(buf);
if (this.mSelectedSessionID.Length > 0x20)
{
throw new TlsFatalAlert(0x2f);
}
this.mTlsClient.NotifySessionID(this.mSelectedSessionID);
base.mResumedSession = ((this.mSelectedSessionID.Length > 0) && (base.mTlsSession != null)) && Arrays.AreEqual(this.mSelectedSessionID, base.mTlsSession.SessionID);
int n = TlsUtilities.ReadUint16(buf);
if ((!Arrays.Contains(base.mOfferedCipherSuites, n) || (n == 0)) || (CipherSuite.IsScsv(n) || !TlsUtilities.IsValidCipherSuiteForVersion(n, this.Context.ServerVersion)))
{
throw new TlsFatalAlert(0x2f);
}
this.mTlsClient.NotifySelectedCipherSuite(n);
byte num2 = TlsUtilities.ReadUint8(buf);
if (!Arrays.Contains(base.mOfferedCompressionMethods, num2))
{
throw new TlsFatalAlert(0x2f);
}
this.mTlsClient.NotifySelectedCompressionMethod(num2);
base.mServerExtensions = TlsProtocol.ReadExtensions(buf);
if (base.mServerExtensions != null)
{
IEnumerator enumerator = base.mServerExtensions.Keys.GetEnumerator();
try
{
while (enumerator.MoveNext())
{
int current = (int)enumerator.Current;
if (current != 0xff01)
{
if (TlsUtilities.GetExtensionData(base.mClientExtensions, current) == null)
{
throw new TlsFatalAlert(110);
}
if (base.mResumedSession)
{
}
}
}
}
finally
{
if (enumerator is IDisposable disposable)
{
IDisposable disposable;
disposable.Dispose();
}
}
}
byte[] extensionData = TlsUtilities.GetExtensionData(base.mServerExtensions, 0xff01);
if (extensionData != null)
{
base.mSecureRenegotiation = true;
if (!Arrays.ConstantTimeAreEqual(extensionData, TlsProtocol.CreateRenegotiationInfo(TlsUtilities.EmptyBytes)))
{
throw new TlsFatalAlert(40);
}
}
this.mTlsClient.NotifySecureRenegotiation(base.mSecureRenegotiation);
IDictionary mClientExtensions = base.mClientExtensions;
IDictionary mServerExtensions = base.mServerExtensions;
if (base.mResumedSession)
{
if ((n != base.mSessionParameters.CipherSuite) || (num2 != base.mSessionParameters.CompressionAlgorithm))
{
throw new TlsFatalAlert(0x2f);
}
mClientExtensions = null;
mServerExtensions = base.mSessionParameters.ReadServerExtensions();
}
base.mSecurityParameters.cipherSuite = n;
base.mSecurityParameters.compressionAlgorithm = num2;
if (mServerExtensions != null)
{
bool flag = TlsExtensionsUtilities.HasEncryptThenMacExtension(mServerExtensions);
if (flag && !TlsUtilities.IsBlockCipherSuite(n))
{
throw new TlsFatalAlert(0x2f);
}
base.mSecurityParameters.encryptThenMac = flag;
base.mSecurityParameters.extendedMasterSecret = TlsExtensionsUtilities.HasExtendedMasterSecretExtension(mServerExtensions);
base.mSecurityParameters.maxFragmentLength = this.ProcessMaxFragmentLengthExtension(mClientExtensions, mServerExtensions, 0x2f);
base.mSecurityParameters.truncatedHMac = TlsExtensionsUtilities.HasTruncatedHMacExtension(mServerExtensions);
base.mAllowCertificateStatus = !base.mResumedSession && TlsUtilities.HasExpectedEmptyExtensionData(mServerExtensions, 5, 0x2f);
base.mExpectSessionTicket = !base.mResumedSession && TlsUtilities.HasExpectedEmptyExtensionData(mServerExtensions, 0x23, 0x2f);
}
if (mClientExtensions != null)
{
this.mTlsClient.ProcessServerExtensions(mServerExtensions);
}
base.mSecurityParameters.prfAlgorithm = TlsProtocol.GetPrfAlgorithm(this.Context, base.mSecurityParameters.CipherSuite);
base.mSecurityParameters.verifyDataLength = 12;
}