How to authenticate username and password using C#

Question

How do I use C # to authenticate my username and password?
I have a username and password and want to see if they are valid.

Is there a way to use Microsoft Graph if possible?

I ran the command below.
GET https://graph.microsoft.com/v1.0/users/{id | userPrincipalName}?$select=passwordProfile

But, passwordProfile is null..

Answer 1

Hi @Anonymous

For security, the Graph api will not return any user's password for you including your own.

If you want to authenticate the username and password, I suggest you can use the ROPC flow, which will return an access token if the username and password are correct.

    var scopes = new[] { "Mail.ReadWrite" };  

    // Multi-tenant apps can use "common",  
    // single-tenant apps must use the tenant ID from the Azure portal  
    var tenantId = "{tenant id}";  

    // Value from app registration  
    var clientId = "{client id}";  

    // using Azure.Identity;  
    var options = new TokenCredentialOptions  
    {  
        AuthorityHost = AzureAuthorityHosts.AzurePublicCloud  
    };  

    var userName = "username";  
    var password = "password";  

    // https://learn.microsoft.com/dotnet/api/azure.identity.usernamepasswordcredential  
    var userNamePasswordCredential = new UsernamePasswordCredential(  
        userName, password, tenantId, clientId, options);  


    var accessToken = await userNamePasswordCredential.GetTokenAsync(new TokenRequestContext(scopes) { });  

    Console.WriteLine("token:" + JsonConvert.SerializeObject(accessToken.Token));  

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Answer 2

Hi @Anonymous , Thanks for Reaching out.

To check or to validate password, please use the below query in C#:

GraphServiceClient graphClient = new GraphServiceClient( authProvider );  
  
var password = "1234567890";  
  
await graphClient.Users  
 .ValidatePassword(password)  
 .Request()  
 .PostAsync();  

Please refer this document.

As we can see from this document , we can see

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Answer 3

thank you for your answer.
When I ran the program I received, it failed to get an access token.

ErrorMessage:
Azure.Identity.AuthenticationFailedException: 'UsernamePasswordCredential authentication failed: AADSTS65001: The user or administrator has not consented to use the application with ID 'xxxx' named 'xxxx'.
Send an interactive authorization request for this user and resource.
Trace ID: xxxx
Correlation ID: xxxx
Timestamp: 2022-05-24 09:02:23Z
See the troubleshooting guide for more information. https://aka.ms/azsdk/net/identity/usernamepasswordcredential/troubleshoot'

InnerException
MsalUiRequiredException: AADSTS65001: The user or administrator has not consented to use the application with ID 'xxxx' named 'xxxx'.
Send an interactive authorization request for this user and resource.
Trace ID: xxxx
Correlation ID: xxxx
Timestamp: 2022-05-24 09:02:23Z

Please tell me how to resolve..