I'm trying to understand how to implement client certificate authentication with Kestrel/ASP.Net Core 6.0 on Windows.
So far I was able to successfully authenticate Firefox and Edge with a client certificate to my server prototype.
Now I want to test failures of client certificate authentication due to invalid certificates and decided to begin with a certificate which has expired.
The first issue I faced was that the browsers I am using are not willing to offer the expired certificate for authentication after I imported them into the MS certificate store, so I was hoping that a more versatile client like curl would allow me to do that.
So I set up WSL and figured out how to successfully authenticate curl with a (valid) client certificate to the server.
Then I switched to an expired certificate and happily noticed that I could not connect.
But after looking more closely at the scenario I'm getting the impression that this is because already curl seems to check the certificate and does note seem to even try to use it -- the reason for me to believe this is that my breakpoint in the certificate validation handler of the server are not hit, while they are hit when I'm testing with a valid certificate. In addition, when I disabled the ValidateValidityPeriod in the server CertificateAuthenticationDefaults options this did not have any effect.
(On the other hand, the pertinent message in the curl output
* TLSv1.2 (IN), TLS alert, certificate expired (557):
* OpenSSL SSL_read: error:14094415:SSL routines:ssl3_read_bytes:sslv3 alert certificate expired, errno 0
starts with TLSv1.2 (IN) - this seems to indicate that the certificate validation failure is on server side, doesn't it? I have to admit that I'm confused.)
Has anyone experience with testing the server side of client certificate validation and could hint me
either to convince curl to use the expired (or otherwise invalid) client certificate or
explain to me why the validation handler in Kestrel are not hit in the debugger or
suggest a different tool for that purpose?
(I alread tried the --insecure switch of curl, but that did not seem to help. I was also considering to write my own client, but I don't like testing self-written software with self-written tools).
Related
Having problems installing PayPalCommerce in OpenCart,
After installing and trying to connect to PayPal I get this error!
"(60) SSL peer certificate or SSH remote key was not OK"
As anybody else come across problem as the server certs are just fine?
As Stated Server Certificats are fine, was thinking of changing the Curl SSL Veerify to False but that would defeat the whole purpose. And as the latest Security 1.2 (whatever abrevation).
Update your certificate authority bundle so that your HTTPS connection to the PayPal API endpoint can verify the connection is trusted.
One can be downloaded here, among other places.
If your attempted connection is using a specific certificate file rather than a CA bundle, delete the old certificate and either obtain the endpoint's current one to use instead or use CA verification of it
Problem Background:
As part of the Computer Networking course assignment, I have been given task of implementing a Proxy Server ( using python socket and ssl module ) that handles https communications between the browser and the origin server (The real server that my browser wants to talk to).
What I have done so far:
I have implemented the above requirement using ssl sockets and also generated self-signed 'cert.pem' 'key.pem' files.
What I need to do:
Now I just need to tell my browser (chrome 89 on kubuntu 20.04) to accept this self-signed certificate and then test the working of my proxy server.
Reading from this stackoverflow question, I can see that I have to:
(1) become my own CA (2) then sign my SSL certificate as a CA. (3) Then import the CA certificate (not the SSL certificate, which goes onto my server) into Chrome.
My confusion/question:
So if I do this, when eventually I am done with this assignment, how do I reverse all these steps to get my browser in the previous state before I had made all these changes. Also, how to reverse the "become your own CA" and also delete the SSL certificates signed by my CA.
Basically, I want my system to return to the previous state it was before I would have made all these changes.
UPDATE:
I have done the previously outlined steps but now I get an error.
Here is a snippet of my code:
serv_socket = socket(AF_INET, SOCK_STREAM)
serv_socket.bind(('', serv_port))
serv_socket.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
context = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
context = context.load_cert_chain('cert.pem', 'key.pem')
context.set_ciphers('EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH')
serv_socket.listen(10)
socket_to_browser, addr = serv_socket.accept()
conn_socket_to_browser = context.wrap_socket(socket_to_browser, server_side=True)
At the last line conn_socket_to_browser = context.wrap_socket(socket_to_browser, server_side=True) an exception is thrown: [SSL: HTTPS_PROXY_REQUEST] https proxy request (_ssl.c:1123)
What am I doing wrong ?
As glamorous as "becoming your own CA" sounds, with openssl it basically comes down to creating a self-signed certificate, and then creating a directory where some CA-specific configuration will be stored (I don't fully remember the specifics, but I think it was just some files related to CNs and serial numbers) so basically reversing the "become your own CA" step is something as mundane as deleting this directory along with the private key and self-signed certificate you were using for the CA. That's it, the CA is no more.
And for chrome returning to the previous state, you would just go the the CA list where you added the CA certificate, select it and delete it. Chrome will stop accepting certificates signed by your CA.
Regarding your new problem... In my opinion, you have developed some kind of reverse proxy (meaning that you expect normal HTTPS requests that you then redirect to the real server) but you have configured Chrome to use it as a forward proxy. In this case, Chrome does not send it a normal HTTPS request, it sends a special non-encrypted CONNECT command and only after receiving the non-encrypted response, it negotiates the TLS connection. That's why openssl says "https proxy request" because it has detected a "https proxy request" (a CONNECT command) instead of the normal TLS negotiation.
You can take a look at How can a Python proxy server (using SSL socket) pretend to be an HTTPS server and specify my own keys to get decrypted data?
It's python, but I think that you'll get the idea
I've always been an end consumer of HTTPS and have never really understood it that well but am looking to change that.
I am calling a RESTful web service over HTTPS. For example...
curl -X GET \
https://myCompanydns/rest/connect/v1.4/myEndpoint
With all my requests I send a basic authentication header i.e a username and password.
When I make these calls via my application I was expecting to have to add a certificate into like a jks (which I've had to do in the past) but on this occasion I've found that I can call the HTTPS web service without that.
For HTTPS to work I believe there is an SSL handshake? How is that happening successfully is this scenario without a jks?
Again, sorry for this beginner type question.
When doing a https://... request the client needs to verify that the servers certificate is the expected one - and not some man in the middle. This is done (among other things) by making sure that the servers certificate was issued by a trusted certificate authority (CA). Which CA is trusted is setup in the local trust store (i.e. local to the client). In the above call where no explicit trust store is given curl is using its default trust store. In the case where you've explicitly gave a jks you've provided the application with a specific trust store it should use.
For more on how the server certificates gets validated see SSL Certificate framework 101: How does the browser actually verify the validity of a given server certificate?.
I am putting a web test up for clients that visit "https://oursite.com/poodlesecurityfailed.js"
Question,
Do I need a valid certificate even though its on a test domain for certificate negotiation? If client can visit it, they failed the poodle test. (SSLv3 is enabled) on that host.
Ideas?
Do I need a valid certificate even though its on a test domain for certificate negotiation? If client can visit it, they failed the poodle test. (SSLv3 is enabled) on that host.
Depends on the client.
If the clients is has enough knowledge to understand, that "invalid certificate" when accessing the site means in reality that the client has still SSL 3.0 enabled, then a self-signed certificate would be enough.
If you instead want to provide an explanation of the problem at this site and don't expect the client to explicitly accept an invalid certificate just to see this explanation, then you should better use a properly trusted certificate.
I am testing a web service with an external partner using 2 way SSL under IIS 7.5. I am requiring SSL, requiring a client cert, and using one to one mapping to authenticate to a domain account. I have configured everything and it works fine on our network (I am able to provide a client cert, get authenticated and invoke the service from browser and test harness).
From outside of our network (in most cases, see below), I am getting a 403.7 error. I have gone through the machine level certificate store and made sure the certificates and CAs are trusted.
Here's the weird thing. I obtained a Type I cert to test from home (and got 403.7 like our intended partner is). So I setup Fiddler to debug SSL and send my certificate, and this works for some reason. I setup a test harness to pass the exact same certificate, and got 403.7. I test in my browser (IE 9), don't get a prompt for a client cert, and get 403.7.
Any help appreciated.
Bill
Last time I checked, IIS was using re-negotiation (by default) to get the client certificate: there is a first handshake where the server doesn't request a client certificate, followed by another handshake (encrypted this time) where the server requests the certificate (via a TLS CertificateRequest message). This will prevent you from seeing anything from Wireshark, unless you configure it to use the server's private key and decipher the traffic (note that this only works with some cipher suites).
One way to see the client-certificate negotiation is to configure IIS to use initial client certificate negotiation, using netsh and clientcertnegotiation=true (which is about initial negotiation). At least the CertificateRequest and the certificate will be sent in clear during the handshake, so you should be able to see this with Wireshark.
If the client isn't sending a certificate to the server as a response to the CertificateRequest, you'll still see an empty Certificate message from the client.
If you don't export the private key with the certificate to use with Fiddler or whichever other client, there is no chance that it will be able to use the certificate. It may at best try to send the certificate, but the handshake will fail (since the CertificateVerify message needs to be signed by the client's private key).
I guess you may encounter a problem whereby:
not presenting a certificate is accepted by the server (it's effectively optional),
presenting an invalid certificate makes it fail and causes this 403.7 status code (many servers and SSL/TLS stacks would implement this as a fatal error, but TLS specification doesn't say that unsupported_certificate, certificate_revoked, certificate_expired, certificate_unknown should be fatal, so this is at the server's discretion).
Are you using the same physical machine to test both the in-network and external-network connections? If not, are you sure that the external-network client has the private key accessible?
I have not configured Fiddler client authentication before. Does it read the client certificate and key from the standard certificate stores? Does it read directly from a PKCS12?
One other thing that may be helpful is inspecting the TLS handshake in WireShark. Specifically, check out the Server's "Certificate Request" message, as the data here clues the client (IE9) which client certificates it should display in the prompt. Compare this for the internal and external connections.