protected SslHandshakeStatus ProcessCertificateRequest(HandshakeMessage message)
{
if (m_State == HandshakeType.ServerKeyExchange) {
CipherDefinition cd = CipherSuites.GetCipherDefinition(m_EncryptionScheme);
if (this.m_RemoteCertificate.GetPublicKeyLength() <= 512 || !cd.Exportable)
throw new SslException(AlertDescription.HandshakeFailure, "Invalid message.");
} else if (m_State != HandshakeType.Certificate) {
throw new SslException(AlertDescription.UnexpectedMessage, "CertificateRequest message must be preceded by a Certificate or ServerKeyExchange message.");
}
UpdateHashes(message, HashUpdate.All); // input message
// get supported certificate types
bool supportsRsaCerts = false;
byte[] certTypes = new byte[message.fragment[0]]; // currently we're not doing anything with the supported certificate types
Buffer.BlockCopy(message.fragment, 1, certTypes, 0, certTypes.Length);
for(int i = 0; i < certTypes.Length; i++) {
if (certTypes[i] == 1) { // rsa_sign
supportsRsaCerts = true;
break;
}
}
// get list of distinguished names
if (m_Options.RequestHandler != null && supportsRsaCerts) { // make sure the client passed a delegate
Queue q = new Queue();
DistinguishedNameList r = new DistinguishedNameList();
int size, offset = message.fragment[0] + 3;
byte[] buffer;
while(offset < message.fragment.Length) {
size = message.fragment[offset] * 256 + message.fragment[offset + 1];
buffer = new byte[size];
Buffer.BlockCopy(message.fragment, offset + 2, buffer, 0, size);
q.Enqueue(buffer);
offset += size + 2;
}
// decode RDN structures
while(q.Count > 0) {
r.Add(ProcessName((byte[])q.Dequeue()));
}
RequestEventArgs e = new RequestEventArgs();
try {
m_Options.RequestHandler(Parent, r, e);
if (e.Certificate != null)
m_Options.Certificate = e.Certificate;
} catch (Exception de) {
throw new SslException(de, AlertDescription.InternalError, "The code in the CertRequestEventHandler delegate threw an error.");
}
}
if (!supportsRsaCerts)
m_Options.Certificate = null; // do not send client certificate
m_MutualAuthentication = true;
return new SslHandshakeStatus(SslStatus.MessageIncomplete, null);
}
private void GetClientCertAtClient(SecureSocket socket, DistinguishedNameList acceptable, RequestEventArgs e) {
Debug.WriteLine("server requested client certificate");
e.Certificate = m_clientAuth.GetClientCertificate(acceptable);
}
private bool IsDistinguishedNameInList(DistinguishedName searchFor, DistinguishedNameList acceptable) {
foreach (DistinguishedName acceptableName in acceptable) {
if (IsNamePartOfOtherName(searchFor, acceptableName)) {
return true;
}
}
return false;
}
/// <summary>
/// see <see cref="Ch.Elca.Iiop.Security.Ssl.IClientSideAuthentication.GetClientCertificate"/>
/// </summary>
public override Certificate GetClientCertificate(DistinguishedNameList acceptable) {
CertificateStore store = new CertificateStore(m_storeLocation, MY_STORE_NAME);
Certificate toCheck = store.FindCertificate();
while(toCheck != null) {
if ((toCheck.IsCurrent) && IsClientCertificate(toCheck)) {
// check, if the root certificate in the chain is known by the server, if yes
// -> server will be able to verify the certificate chain
Certificate[] chain = toCheck.GetCertificateChain().GetCertificates();
if (chain.Length >= 1) {
// last certificate in the chain is the root certificate
if (IsDistinguishedNameInList(chain[chain.Length - 1].GetDistinguishedName(),
acceptable)) {
return toCheck;
}
}
}
toCheck = store.FindCertificate(toCheck);
}
return null;
}
/// <summary>
/// see <see cref="Ch.Elca.Iiop.Security.Ssl.IClientSideAuthentication.GetClientCertificate"/>
/// </summary>
public override Certificate GetClientCertificate(DistinguishedNameList acceptable) {
return m_clientCertificate;
}
/// <summary>
/// see <see cref="Ch.Elca.Iiop.Security.Ssl.IClientSideAuthentication.GetClientCertificate"/>
/// </summary>
public virtual Certificate GetClientCertificate(DistinguishedNameList acceptable) {
return null;
}
