(.NET Core C#) NTLM Client and Server Code

Demonstrates the NTLM authentication algorithm for both client and server.

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// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Ntlm ntlmClient = new Chilkat.Ntlm();
Chilkat.Ntlm ntlmServer = new Chilkat.Ntlm();

// The NTLM protocol begins by the client sending the server
// a Type1 message. 
string type1Msg;
ntlmClient.Workstation = "MyWorkstation";
type1Msg = ntlmClient.GenType1();

Debug.WriteLine("Type1 message from client to server:");
Debug.WriteLine(type1Msg);

// If the server wishes to examine the information embedded within the
// Type1 message, it may call ParseType1. 
// This step is not necessary, it is only for informational purposes..
string type1Info = ntlmServer.ParseType1(type1Msg);

Debug.WriteLine("---");
Debug.WriteLine(type1Info);

// The server now generates a Type2 message to be sent to the client.
// The Type2 message requires a TargetName.  A TargetName is
// the authentication realm in which the authenticating account
// has membership (a domain name for domain accounts, or server name
// for local machine accounts).
ntlmServer.TargetName = "myAuthRealm";

string type2Msg = ntlmServer.GenType2(type1Msg);
if (ntlmServer.LastMethodSuccess != true) {
    Debug.WriteLine(ntlmServer.LastErrorText);
    return;
}

Debug.WriteLine("Type2 message from server to client:");
Debug.WriteLine(type2Msg);

// The client may examine the information embedded in the Type2 message 
// by calling ParseType2, which returns XML.  This is only for informational purposes
// and is not required.
string type2Info = ntlmClient.ParseType2(type2Msg);

Debug.WriteLine("---");
Debug.WriteLine(type2Info);

// The client will now generate the final Type3 message to be sent to the server.
// This requires the Username and Password:
ntlmClient.UserName = "test123";
ntlmClient.Password = "myPassword";

string type3Msg;
type3Msg = ntlmClient.GenType3(type2Msg);
if (ntlmClient.LastMethodSuccess != true) {
    Debug.WriteLine(ntlmClient.LastErrorText);
    return;
}

Debug.WriteLine("Type3 message from client to server:");
Debug.WriteLine(type3Msg);

// The server may verify the response by first "loading" the Type3 message.
// This sets the various properties such as Username, Domain, Workstation,
// and ClientChallenge to the values embedded within theType3 message.
// The server may then use the Username to lookup the password.  
// Looking up the password is dependent on your infrastructure.  Perhaps your
// usernames/passwords are stored in a secure database.  If that's the case, you would
// write code to issue a query to get the password string for the given username.
// Once the password is obtained, set the Password property and then 
// generate the Type3 response again.  If the server's Type3 response matches
// the client's Type3 response, then the client's password is correct.

bool success = ntlmServer.LoadType3(type3Msg);
if (success != true) {
    Debug.WriteLine(ntlmServer.LastErrorText);
    return;
}

// The Username property now contains the username that was embedded within
// the Type3 message.  It can be used to lookup the password.
string clientUsername = ntlmServer.UserName;

// For this example, we'll simply set the password to a literal string:
ntlmServer.Password = "myPassword";

// The server may generate the Type3 message again, using the client's correct
// password:
string expectedType3Msg = ntlmServer.GenType3(type2Msg);

Debug.WriteLine("Expected Type3 Message:");
Debug.WriteLine(expectedType3Msg);

// If the Type3 message received from the client is exactly the same as the
// expected Type3 message, then the client must've used the same password,
// and authentication is successful