I deployed an application out to our app service in Azure, and the app needs to have SSL to run, but since it is still in development I did not want to have to purchase a cert yet, so I created a self-signed cert through openssl. The private key is 2048 bits, which should be enough, but when I go to apply the cert to the hostname, it just sits there and never applies.
Is there a special step you have to complete to get self signed certs to work, or, are you not allowed to use self signed certs in Azure App Services?
Try to use ServerCertificateValidationCallback to monitor the verification of server certificate, comparing the certificates between local and server or just returning true.
Now when you invoke the https service in your web app, the verification callback will be invoked automatically. If failed, you will see the errors. If successful, the service response will be returned.
For more details refer this article: http://devchat.live/en/2017/09/29/how-to-invoke-https-service-protected-by-self-signed-certificate-from-azure-app-service/.
Related
I uploaded a self signed certificate chain in .pfx format to our App Service instance and configured SNI TLS/SSL Binding. For some reason only the server certificate with depth 0 is returned although I would expect the intermediate and root cert as well.
Has anyone else encountered this behaviour? Am I missing something?
After talking to the Tech-Support at Microsoft, i have been told it is not possible to return full self-signed certificate chains via App Service for security reasons. It is however possible to use Application Gateway for SSL offload with self signed certificates.
How can I create a certificate chain (Self Signed) for Azure Web App? I turned on the settings in the code and Incoming client certificates.
But in the logs I see an error:
OfflineRevocation The revocation function was unable to check revocation because the revocation server was offline
Certificate was not authenticated. Failure message: Client certificate failed validation.
You may use the New-SelfSignedCertificate command from Powershell to create a new self-signed certificate for testing purposes. For example:
PS C:\> New-SelfSignedCertificate -DnsName "www.fabrikam.com", "www.contoso.com" -CertStoreLocation "cert:\LocalMachine\My"
This creates a self-signed SSL server certificate in the computer MY store with the subject alternative name set to www.fabrikam.com, www.contoso.com and Subject and Issuer name set to www.fabrikam.com.
Once you have the cert, you may upload it to your App service. Check this post on MSDN for more details on the working solution. However, do note that you might still see some certificate validation errors if the cert is self-signed. Consider using a free App Service Managed Certificate or the App Service certificate as they already satisfy the prerequisites of App Service.
Hope this helps.
References:
Add an SSL certificate in Azure App Service
Secure a custom domain
For testing purposes I would like to enable the 'Incoming Client Certificates' option in my Azure App Service (running a WCF webservice), and see if my Client application can still connect to the webservice. Since I am still in a testing phase, my app service still has the .azurewebsites.net domain name.
However, I can't seem to figure out how to get a proper client certificate that the server will accept (without switching to a custom domain name, which I know will work).
Currently, I see 2 possible routes to a solution:
Somehow get my hands on .cer that is signed by a CA trusted by the App Service server.
Generate a self-signed .pfx and .cer with my own self-signed CA. Import the pfx on the App Service and install the .cer on the client.
Both directions have not yielded any success so far. Does anyone have any experience with this?
Per my understanding, the client certificate is used by client systems to make authenticated requests to a remote server. In this case, your webservice is the remote server in a C/S mode. As you point out, "validating this certificate is the responsibility of the web app. So this means that any certificate will be valid as long as you don't validate anything". It does not effect on whether you have a custom domain or not in your web app service.
If you want to use client cert authentication with Azure app, you can refer to How To Configure TLS Mutual Authentication for Web App.
If the server has requested client certificate in its server hello and the client cert has signing capability, then it is expected to send the CertificateVerify message to the server. It contains signed hash of all messages from Client Hello till that point which are buffered on the server side. The server TLS layer will decrypt this using the client public key (which is in the Client certificate received earlier) and compare with its calculated hash. It will call back to application layer if this fails.
The application needs to handle it at that point and return its own error or continue with the session. https://www.rfc-editor.org/rfc/rfc5246#section-7.4.8
One example of this with Wolfssl library is https://github.com/wolfSSL/wolfssl/blob/14ef517b6113033c5fc7506a9da100e5e341bfd4/wrapper/CSharp/wolfSSL-Example-IOCallbacks/wolfSSL-Example-IOCallbacks.cs#L145
I have a cloud service and an Azure APIM instance with a self signed client cert setup on them (the cert has intended purposes of server auth and client auth).
Each API within the APIM has the client cert setup on its security. However, when I perform the call the following comes back in the trace.
"messages":["Error occured while calling backend service.","The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel.","The remote certificate is invalid according to the validation procedure."
Is there anything I am missing here, searching online and cannot see anything obvious.
Yes you are correct, the option is not available in the portal to allow self-signed certificates. Here is a blogpost by Sasha Rosenbaum: http://divineops.net/enable-self-signed-certificates-in-azure-api-management-services/
Here basically you are skipping the certificate verification using "skipCertificateChainValidation" attribute.
You can create a backend entity through power shell scripts to skipcertifioc
I'm adding support for JWT tokens in my Web Application, and I have an X509 certificate which it needs for signing those tokens.
I have rejected the idea of using the same certificate we use for HTTPs (see Can I use the Private Key Certificate of Web App to sign JWT?).
I think a self signed certificate should do the trick, in fact I can't see any advantages of a web of trust in this scenario (that doesn't mean there aren't any, I just can't think of any).
The web application runs on a farm of web servers. My current plan is to generate a self signed cert and put the X509 certificate into the certificate store in Windows on each machine. Our IT department are checking, but they think they can roll that out to all the Web Servers in the farm using Group Policy. So this seems like a feasible plan.
The certificate store in windows looks pretty confusing to me. I think there are two options:
1) Put it in "My" store for the user under which the IIS App pool run. There are many app pools, so potentially the certificate will be in many stores.
2) Put it under the LocalMachine store, and then grant explicit access to the specific certificate for the IIS user(s).
3) Something else I can't think of.
Is there a "correct" place for these type of certs, and if so where is it?
The usual CertificateStore for signing certificates is the My store. I normally place them in LocalMachine location, but it is probably safer to put them in the certificate store for the Application Pool identity itself.
I would then give the Application Pool read-only access to this certificate only (right click certificate, then 'All Tasks' > 'Manage Private Keys', then add your Application Pool identity and give 'Read' permissions only.