Webservice security - What is the best option? - web-services

I would like to secure our webserives. However I am not entirely sure how this is done. Needless to say that I am pretty new to this. Here is what I would like to have. I would like to authenticate the user against lets say database/activedirecrtory or even a third party authentication. Now if the user is authenticated, I would like to use a token or principal (machine specific) and send that to the webservice. Is this possible? If yes, would the principle be sent out in clear text? Basically I am asking for guidance on how to implement security in webservices.

If you're using WCF, then the default is to use the wsHttpBinding, which uses WS-Security. You then get to choose how to authenticate the user. I believe the default would be Windows authentication.

Read up on HTTP Digest Authentication. If you set the highest QOP and use client nonce values, it's quite nice.
Your question is missing some really important architectural details. If you're using REST, then you must use something like HTTP Digest. You might also want to use SSL.

Related

C++ grpc service: how to store custom session data

I want to implement a custom authentication logic and when a user authorized using special method I want to set a server side session variable which represents user id to use in other requests. How it's possible to implement the behavior in C++ GRPC server?
Could you clarify what do you need? Do you need customized authentication or authorization? Once TLS handshake completes in gRPC, you can get auth information from AuthContext and then make authorization decision.
In addition to Jiangtao's answer which is related to grpc_server_credentials, you probably also want to take a look at grpc_auth_metadata_processor, which is used on servers to process the auth metadata on the request and determine whether the request will be allowed.
From your description, it looks like you are trying to do some additional authorization decisions, besides gRPC authentication. If that's the case, it's not a bad idea to separate your authorization logic apart from gRPC. You could probably do the normal gRPC authentication, get the information from the AuthContext as Jiangtao mentioned, and then proceed with your custom logic. "Inject" the authorization logic into gRPC stack might not be a good choice here. Please let us know if you have any further questions and we are happy to help! :-)

Security about a simple REST web service

Here is my little API with two URL :
/api/location/list -> GET
/api/location/detail -> GET
I'm looking for a process to secure this service with authentication. For now, it can be accessed by only one user (me).
I think oAuth is too complex in my case and I found this resource for designing a simple API.
I understand the principle of private/public key and HMAC but I have a big concern about this :
Say my webservice is consumed by an ajax request with GET verb. I have something like /api/location/list?apikkey=userid&hash=abcde.
A end user can easily sniffed the network during the request (via a simple chrome console), capture full url and access directly to the service multiple times (I think it's a case of replay attacks).
Differents resources talk about timestamp or nonce to make a request unique but I'm a bit lost with implementation.
Any ideas ?
You can try JWToken auth specs, simpler than Oauth, but avoid authorization data as url parameter if possible and use Header's request instead.
If needed consider also ssl encryption at tcp level.
Perhaps you could try to use a token-based approach for security, as described in this blog post:
Implementing authentication with tokens for RESTful applications - https://templth.wordpress.com/2015/01/05/implementing-authentication-with-tokens-for-restful-applications/
The idea is to authenticate to an authentication resource (that can be part of your application) to get temporary token that can be refreshed with a refresh token when expired.
With the use of HTTPS, it seems to be appropriate.
I think that it depends on the security level you expect. Signature-based authentication (the AWS approach) is great but is a bit complex to implement by hand.
Hope it helps you,
Thierry

Building an Oauth2 API service, what is the use of client_secret

Good morning, we are a little company in Europe, and we need to set up some webservice for internal and external use. We decided to implement an autentication to those webservices, and i though to implement an Oath2 authentication. The problem is the following (besides the fact that i've only used the Oauth2 standard one time) that i do not really understand the use of the "client_secret", from the point of view of the service provider. Isn't the client_id enough to identify a client? Why is the client_secret needed exactly and how is it to be implemented in the general logic of the application?
Thank you for any response.
You want to make sure that the client requesting credentials is who you think they are, and the client ID is used in requests that users can see (in the URL). Without a client secret anybody could pretend to be any client application to trick users into granting access.

How can I implement security in web service?

I have a REST service that is called by a mobile app; I need the user to login, then the service generates a unique token associated to user id and this pair of userId/token is passed to every subsequent call to the WS.
I don't like too much this solution because, even if very difficult, if I change the uid and get the right token I can "login" as another user, so I'm trying to understand which is the best practice to handle web service authentication for a mobile (and non) application.
Your issue is not with the methodology, but the fact your service is not checking the combination of UID and token, but rather the token. That is a programming issue, not a methodology issue.
How secure do you need the service to be? Are you talking top secret level of security? Banking? My soccer club site? For high levels of security, you can use digital certificates, but it makes for a much more complex provisioning methodology. But ... Even if you are going to change from UID/Token (or AppId, User, etc), you still need to fix the fact that correct token + wrong UID works. That is a mistake if two-form authentication is a must. Changing methods will solve nothing if you don't have the proper programming on the server side to avoid circumventing the system.
You may also want to look at how you provision the Token. Should this be offline, or is one REST sign up method acceptable. This leads back to the level of security your require.
You might want to forget the token/id solution and consider going the SSL/basic authentication route. SSL will provide the encryption and secure communication, but will not secure the access to your specific web-services on the server side.
For that you can try standard basic http user/password authentication on every call. This way you do not need to worry maintaining state through each REST call. Each call will have an explicit reference to the user. Yes, you will need to re-authenticate the user with each call which is a bit of a pain, but you can cache your results.
However, I am far from an expert on the subject.

How can an authentication key be passed to a restful web service?

Some existing web services I consume have methods that look something like this:
List<Employee> employees =
employeeService.GetEmployees(accessKey, allDepartments);
The accessKey serves two purposes; it acts as both authentication and identification. Only valid access codes are responded to (authentication) and it services as a link to a particular client's data.
If the services were to be done a restful manner I'm not sure how this would be achieved. I definitely would not want to do something like this:
http://www.business.com/<GuidHere>/Employees/
Since this would show the accessKey, which is somewhat secret, (ie, its usually in an encrypted file on the client which uses this) we can't show the GUID in a URI. How is something like this achieved using a restful architecture?
You could send the authentication token using HTTP headers.
If this is a RESTful web service I'm assuming it's being consumed by a machine so why not pass the access key in the url?
At then end of the day you need to put it somewhere and hiding them in hidden form fields in the browser (if the service is to be browsable) isn't much in the way of security.
If the key is so sensitive, why not symmetrically encrypt on the server per session and pass that value around instead?
Just some thoughts.
Kev
If time isn't an issue implementing OAuth security may be useful. OAuth uses a public key, and also a secret. The mess is hashed (in most cases) and the server will use the public key + it's copy of the secret to do the same hashing and make sure its result matches the requests.
The benefit is you wouldn't need to use HTTPS or POST. Get* REST api methods should be using the HTTP GET method (I'm not sure if being RESTful is your goal, just thought I would point that out). I agree with Mr. Pang, use http://www.business.com/employees. The query string could contain the list of department ids.
For your case the service call wouldn't have the 'accessKey' argument, rather it would become the public key (I imagine) and be used in either the headers, query string, or as a POST param.
Some good info on OAuth: http://www.hueniverse.com/hueniverse/
As Troy Alford pointed out, my original suggestion was incorrect. You shouldn't be using POST in a situation like this. You should use a GET request with the authentication information in the HTTP headers. Take a look at basic access authentication for one way to do that.