I have multiple sets of sensor networks that are sending data to a .net web api. Somehow, I need to secure some of the endpoints of the API (so that I can be certain that the information sent to the API really is from the sensors). Basic auth and SSL seems to be one way to go. The problem is that I'm having trouble understanding the SSL part.
As of now I have created a client certificate that is stored on the sensors, information of the certificate can be retrieved in the API by the Request.GetClientCertificate() method. Is this overkill when I just want to secure my Api with basic auth? That is, is the communication secure by just sending data over https without providing a certificate?
I do not need to use the certificate for authentication (since this is done by basic auth).
Basic authentication is about sending the user name and password in the HTTP authorization header as plain text (base64 encoded but not encrypted). For this reason, you need to use HTTPS with basic authn so that folks in the middle do not get to see the user name and password that a client sends.
When it comes to HTTPS, there is a server certificate and a client certificate. Server sends the server certificate to the client so that client can determine it is the right server it is connecting to. Similarly, a client can send a client certificate to the server so that a server can determine if an authentic client is talking to it.
The client certificate part is optional in HTTPS. So, you can use basic authentication without using the client certificate. If you use client certificate, it is already a credential and you need not use basic authentication, unless you want to use a two-factor authentication. TFA is an overkill or not - it is for you to decide.
Related
I'm working with an old legacy app at work that's written in ASP.NET 4. We recently started migrating to the cloud and we had to expose one of the endpoints so that our api gateway (Apigee) can call it. What is the correct way to restrict this endpoint so that it only allows calls from Apigee? I'm aware 2-way-ssl should solve this issue but that requires changes on the Apigee side and we don't have control over that. Is there something I can do on the API side to confirm that the certificate in the request is specifically from Apigee?
You're describing the need for what is sometimes called 'southbound' authentication. Specifically mutual-TLS sometimes called client authentication, as opposed to standard (or one-way) TLS where only the server is being authenticated by the calling client. You're right: mTLS (a.k.a., "two-way SSL") is one means to allow your back-end server to authenticate the calling Apigee-layer 'client'.
When you want client authentication via TLS (mTLS) you need to configure your back-end server endpoint to require mTLS at the time of the handshake, and to have stored in its Truststore the signing CA certificate of the client certificate you expect to see offered up by the calling client at time of connection. Done right, your server
requires mTLS and shuts down the handshake if the client won't
offer a client cert,
validates the client cert is authentic as being issued by a recognized signing CA (Truststore), and
is the actual client cert expected to be seen (e.g., by matching the expected distinguished name).
Here's an authoritative support-community article about doing all this, within Apigee: https://community.apigee.com/questions/63337/mutual-tls-between-client-to-edge-and-edge-to-back.html
Now most of the SSL authentication is implemented directly through third-party libraries, suddenly I want to know the two-way authentication, the client and server exactly how to use the information inside their respective certificates for authentication. For example, we have client certificates and server certificates, and we have extracted the contents of both certificates. How can we determine whether the authentication is successful or not?
I've been reading and trying to comprehend the differences in browser side security. From what I gather, SSL is used to keep people from sniffing the traffic you send to the server. This allows you to send a password to a server in clear text...right? As long as you are in an SSL encrypted session you don't have to worry about hashing the password first or anything weird, just send it straight to the server along with the username. After the user authenticates you send them back a JWT and then all future requests to the server should include this JWT assuming they are trying to access a secured area. This allows the server to not even have to check the password, all the server does is verify the signature and that's all the server cares about. As long as the signature is verified you give the client whatever info they are requesting. Have I missed something?
You are correct. "This allows the server not to even have to check the password." Why would you have to check a password on each request?
A JWT is a means of verifying authentication. It is generated upon a successful authentication request and hence forth passed with each request to let the server know this user is authenticated.
It can be used to store arbitrary values such as user_id or api_key but they are not very secure so don't store any valuable information here.
Be wary though, if a plain JWT is intercepted by a third party, it can assume this user's session and possible data.
SSL is a lower level form of security, encrypting every request from and to the server to prevent interception and retains integrity.
SSL is achieved by (purchasing) an SSL certificate and installing it on your server. Basically an SSL certificate is a small data file that binds a cryptographic key to an 'organisation'. Once installed succesfully, HTTPS requests (on port 443 by default) are possible.
Don't know much about encryption...
Say I'm preparing a SAML request to submit to an identity provider. Why would I need to apply an x.509 certificate to this request? Is transmission over SSL alone not secure enough?
In the case of SAML, message-level security (i.e. the XML itself is signed and sometimes encrypted) because the communication involves parties that don't communicate directly. SSL/TLS is for transport-level security, only used between the two parties that are communicating directly and for the duration of this communication only.
Depending on which SAML binding you use, the dialog can look like this (e.g. along the lines of Shibboleth):
User's browser connects to Service Provider (SP)
SP gives the user a SAML request, not necessarily visible, but hidden within a form or equivalent.
User's browser (in a direct connection to the IdP) sends the SAML request to the IdP.
The user authenticates with it and gets a SAML response back.
The user's browser sends that SAML response to the SP.
In this scenario, there is no direct SSL/TLS connection between the SP and the IdP, although all 3 parties are involved. (Some variants of this involve a back-end communication between SP and IdP for attributes, but that's a different problem.)
An SSL/TLS connection wouldn't be sufficient for the IdP to know that the SAML request came from an SP for which it's allowed to authenticate and release attribute, since the connection to the IdP comes from the user's browser, not the SP itself. For this reason, the SP must sign the SAML request message before handing it to the user's browser.
An SSL/TLS connection wouldn't be sufficient for the SP to know the SAML response came from an IdP it trusts. Again, that's why the SAML response itself is also signed.
What applies to signing also applies to encryption, if the middle party, i.e. the user, isn't meant to see what's in the SAML message and/or if the connection between the user and the SP or IdP isn't over SSL/TLS (usually, it should be over HTTPS).
Yes - SSL is enough - but SSL is only point-to-point. You cannot secure your connection using SSL if there are a few intermediaries in the way between your source and your target machine.
In that case, e.g. when transmitting over the internet, you must safeguard the actual message, instead of the transport-level. That's why you need to encrypt the XML (or at least parts of it).
Marc
All that HTTPS will do is encrypt the communication between two points and prevent eavesdroppers -- it won't confirm who it was that sent the message. Neither will it assure secure communication if your message is then forwarded.
If you sign your request with the X.509 certificate you can be assured the decryptor has the shared secret contained in certificate. In other words, you can be assured the message can only be decrypted by the organisation you want it to be decrypted by.
In your case, the X.509 encryption requirement means that you should be assured that the identity provider is the only organisation that will receive your request.
A useful Wikipedia primer is here.
Most likely because they want to authenticate you (the client). HTTPS can be used for client authentication, but it rarely is in practice.
In practice, you could use HTTPS (SSL/TLS) to protect your SAML message. But you would want to use two-way SSL certificate verification/validation, meaning your client would need to verify the server's X.509 certificate and the server would need to be configured to perform client authentication, which would require it to check an X.509 certificate that the client presents. So, the client would need its own certificate anyway.
SSL/TLS is not really designed for this...it was/is designed to protect web traffic from being seen while in transport and for the client to be able to tell what server they are talking to and sending sensitive information to (it was really designed for e-commerce where the client (user buying something) knows who they are sending their credit card information to). In the case of SAML, the whole point is for the parties to know that the information they are exchanging has not been altered in transport and that each is talking to who they think they are. Using certificates to sign/encrypt that message itself accomplishes that.
I'm looking for an existing HTTP protocol for securing authentication but not the payload that follows. I want the server to store the username, hashed password and different salt per user.
HTTP Digest Authentication fails these requirements because all accounts use the same salt. SSL fails because it encrypts the entire connection.
Edited to add:
This is for a desktop client talking to a web service (no browser involved)
The popular scheme is to have login form protected by SSL, while rest of the site doesn't use SSL. See for example popular social networking sites.
Why not just have your authentication mechanism protected by SSL and then forward to the rest of your application which runs under normal HTTP?
How about OpenID? Is there a reason that you have to store authentication information?
Edited to add
Sorry didn't catch that it was a desktop app. How about OAuth?
Is there a way that you could structure the original request URL to indicate the user? Then, the server could respond with a different different realm (acting as "salt") for every user in the HTTP digest authentication response. For example, request URLs of the form http://user.y.com/service or http://www.y.com/user/service would result in a challenge response like:
WWW-Authenticate: Digest realm="user#y.com", nonce="oqa9hvq49krprkphtqc"
Can you explain what's driving the "no encryption" mandate? If you are subject to man-in-the-middle attacks, you need to protect the integrity of the entire request. There, SSL would be very helpful. If you absolutely cannot have encryption, would SSL using an unencrypted cipher suite be acceptable?