I have Azure API Management, configured internally and exposed to the public through Azure application Gateway. My API is secured for client certificates, it working perfectly when I test it internally. When I test it externally, I am getting an invalid certificate error. Does Azure Application Gateway block client certificates? How to allow them?
An answer from Microsoft:
We do have option for mutual authentication on Application Gateway
which can allow the mutual authentication between client and
Application Gateway:
https://learn.microsoft.com/en-us/azure/application-gateway/mutual-authentication-overview
However this is still in preview version, which is not included in
SLA. As the mutual authentication between AppGW and the APIM we
double confirmed with the backend engineers, unfortunately the answer
is no we do not support such a function.
I suspect this is not yet possible with Application Gateway: https://feedback.azure.com/forums/217313-networking/suggestions/9379902-allow-mutual-ssl-auth-on-application-gateway
Related
I want to implement client certificate validation in Azure API Management policy to check if the client has a valid certificate as per the below documentation.
https://learn.microsoft.com/en-us/azure/api-management/api-management-howto-mutual-certificates-for-clients
I have Application gateway in front of API Management service deployed in internal mode connected to vnet.
I have the same issue as mentioned in the below artile. The certificate is not being passed down to the APIM.
Client Certificate is not being passed on by Azure Application Gateway
I see that there is support for Mutual Authentication with application gateway in preview mode. Is this the only possible option to fix this issue. Any timelines on the release for this feature on v1 application gateways.
https://learn.microsoft.com/en-us/azure/application-gateway/mutual-authentication-overview
Will the certificate be passed to APIM gateway to validate the client certificate with this feature enabled.
My APIM policy works fine when the traffic is coming to the internal endpoint when I try to access the API from within the network. This route doesnt pass through Application gateway in our setup and works fine. But having trouble getting the external access enabled with client certificates
"Will the certificate be passed to APIM gateway to validate the client certificate with this feature enabled" - no, it won't.
An answer from Microsoft:
We do have option for mutual authentication on Application Gateway
which can allow the mutual authentication between client and
Application Gateway:
https://learn.microsoft.com/en-us/azure/application-gateway/mutual-authentication-overview
However this is still in preview version, which is not included in
SLA. As the mutual authentication between AppGW and the APIM we
double confirmed with the backend engineers, unfortunately the answer
is no we do not support such a function.
I have been looking at various tutorials demoing how identity management works as well as API management in azure but I am not seeing an answer to my questions. I understand that managed identities can be used to authorize azure resource to resource communication but I am not seeing how this is done for a web application. Say for example I have an angular website being hosted on an nginx server in an AKS cluster. I understand that I could use Identity management to create Identity resources that make it so that the AKS and APIM are authorized to connect with one another but how would I do this for the angular running application? This application is running in the client's browser, so it seems like this identity management mechanism would not work. How does one secure an APIM so only a given web application can interact with it?
You could secure your API in APIM with the client certificate, then when the app access the API, validate the incoming certificate and check certificate properties against desired values using policy expressions.
For more details, see How to secure APIs using client certificate authentication in API Management.
I am playing around with Azure API Management as a SOAP passthrough. I was hoping to get some analytics in place to preview the service.
My trouble is that my client endpoint has SSL validation in place. I can't figure out how to load the .cer file in Azure to satisfy this requirement. At the very least I was hoping to find an option to turn off SSL validation (like I can with curl or even postman).
any one found a way to accomplish this?
API Management provides the capability to secure access to the back-end service of an API using client certificates. Below guide shows how to manage certificates in the API publisher portal, and how to configure an API to use a certificate to access its back-end service.
How to secure back-end services using client certificate authentication in Azure API Management
If you are calling the API Management service with https then the certificate that is presented will match the host name that you are calling with. I'm assuming you were able to change the client to point to your service at https://{servicename}.azure-api.net ?
Or did you change your local hostname file to make that happen? If that's the case, then that is why you are getting an SSL error. Without being able to re-compile your client you cannot disable the SSL validation.
You could configure the custom domain in API Management and if you have access to the certificate, you could attach it to the custom domain. However, you would actually have to change the public DNS for the domain to make that work. I don't think you can enable a custom domain in API Management, provide the certificate and only use your local hostname file to do the mapping. But I will check.
The steps under 'Scenario 7: The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel' in Troubleshooting 4xx and 5xx Errors with Azure APIM services is what worked for me. I'm using this approach to bypass validating the SSL cert until I switch from using a self-signed cert to a CA signed one.
I'm settings up a Service Fabric cluster in Azure and want to run a web API (using .NET Core) over https. I want to use my CA-signed wildcard (*.mydomain.com) certificate to access this API. But I'm a bit confused as to where I use it when I create the cluster, is it the cluster or client certificate? I'm thinking the client certificate, but the documentation states that this is for admin tools (i.e. the Explorer), so I'm unsure on how to proceed.
And yes I've read a ton of posts and resources, but I still find this confusing.
There are three certificate types. Here is a summary overview of them.
The Cluster certificate is used for the Explorer endpoint and is deployed to the primary nodes. So if you add your *.mydomain.com wildcard cert there, and CNAME something (e.g. manage.mydomain.com) to [yourcluster].[region].cloudapp.azure.com, then when you hit your management endpoint that cert will be what will be presented to the web browser.
The Reverse Proxy SSL certificate is deployed to each of the nodes and is used when using the built-in reverse proxy feature of Service Fabric. In this case this is what is being used when you hit https://api.mydomain.com/YourAppName/YourService/Resource (where api.mydomain.com is another CNAME to yourcluster.region.cloudapp.azure.com). This is used as an alternative to running your own reverse proxy or other offloading layer (Application Gateway, IIS, nginx, API Management, etc).
The Client certificates are used in place of Azure Active Directory authentication to the management endpoint. So instead of managing users in AAD (with the _Cluster AAD application and the Admin / Read-Only roles), you manage access by handing out management certificates (Admin or Read-Only) to your trusted users.
You can also have secondaries these certificates to use in certificate rollover situations.
The way we are using it is to have Application gateway configured in front of service fabric cluster, and web certificate is uploaded to Application Gateway (and dns is pointing to application gateway) In that scenario SSL is terminated at application gateway.
Another possibility is to terminate SSL at each node in service fabric cluster, in this scenario you would need to ensure that certificate gets deployed to each of the nodes.
As for cluster vs client certificate dilemma, I am also confused, but I think the answer is neither. Client certificate is not for sure since this certificate is used to identify you as admin when running service fabric admin ps scripts.
I do not think it is cluster certificate either, here is what MS docs say what it is used for:
Cluster and server certificate is required to secure a cluster and prevent unauthorized access to it. It provides cluster security in two ways:
Cluster authentication: Authenticates node-to-node communication for cluster federation. Only nodes that can prove their identity with this certificate can join the cluster.
Server authentication: Authenticates the cluster management endpoints to a management client, so that the management client knows it is talking to the real cluster. This certificate also provides an SSL for the HTTPS management API and for Service Fabric Explorer over HTTPS.
as far as I am reading into it, this certificate is used for internal cluster authentication, and it is also used so your management tools can be asured that they are working with right cluster.
I have multiple Web APIs deployed in Azure without applying authentication, so anyone has access to internet has the access to the Web APIs.
Now I would like to apply authentications to the Web APIs, instead of implementing the same authentication logic in different Web APIs, I found Azure API gateway (API management) is a potential solution.
With Azure API management documentation, I learned I can apply policies like validate-jwt to authenticate requests to back end Web APIs. However, endpoints of the back end Web APIs are still available to users.
So, how should I hide them? Must I define a sub network or does Azure API management have a feature for this?
Recently I also had this same problem. Finally I found the solution by using 'IP Restrictions' function. See the following steps:
1) Go to your API management Overview page in Azure portal, copy the VIP.
2) In your Web APP > Networking
3) Paste in your VIP
Microsoft's Solution: How to secure back-end services using client certificate authentication in Azure API Management
Using this approach, any attempt to access a back-end service without the required certificate will result in a 403 - Forbidden response.
You can use a self-signed certificate as opposed to using a trusted CA signed certificate ($$). I chose to implement an Azure Key Vault where I generated a new certificate, downloaded it as a *.PFX file, and uploaded it into my API Management instance as described in the article.
Here is an answer from #PramodValavala-MSFT
https://github.com/MicrosoftDocs/azure-docs/issues/26312#issuecomment-470105156
Here are options:
IP restrictions (as described by #redman)
Function keys
Authentication/Authorization for Functions
Managed Identity for APIM
p.s. in my case I want with IP restrictions since it allows to keep all of the auth on the API Management Gateway.
Or you could use:
Basic auth
Mutual certificate auth
VPN
to secure Azure API Management service communication with your backend service.
Look into setting up TLS on Azure API Management so that all connections to your backend API must come through the API proxy.
Azure API management cannot modify your backend service. It's role is limited to being a proxy.
You will have to apply authentications to each Web API or configure your firewall to accept requests only from Azure APIM.
Is your backend app an Azure Function app or an App Service app?
If so, Managed Identity may be the simplest way to restrict access. No need to store client secrets/certificates in the API Management + not as flaky as IP whitelisting method.
Create an Azure Active Directory Application for the Function App.
Enable Authentication/Authorization module on the Function App and reference the AAD app from step 1.
Enable a Managed Identity on the APIM instance.
Add a <authentication-managed-identity> policy to the APIM and reference the AAD app from step 1.
I've blogged about this approach in more detail in Restrict Azure Functions to API Management with Terraform
Reference:
Use managed identities in Azure API Management
Configure your App Service or Azure Functions app to use Azure AD login