Openssl Self Signed Wildcard Certificate

  1. Openssl Wildcard Certificate
  2. Openssl Self Signed Wildcard Certificate Download
  3. Openssl Generate Self Signed Certificate
  4. Create Self Signed Certificate Openssl
-->

Here’s the information you’ll need to fill out in your Certificate Signing Request for your Wildcard SSL CSR: Common Name (CN) – Your fully-qualified domain name goes here. Organization Name (O) – The legal name of your company or organization. Echo ' This will generate a non-secure self-signed wildcard certificate for given domain. ' echo ' This should only be used in a development environment. ' exit: fi # Add wildcard: WILDCARD= '. $DOMAIN ' # Set our CSR variables: SUBJ= ' C=US: ST=NY: O=Local Developement: localityName=Local Developement: commonName= $WILDCARD: organizationalUnitName=Local Developement: emailAddress= '.

When using self-signed certificates, there are different ways to create and use them for development and testing scenarios. In this guide, you'll cover using self-signed certificates with dotnet dev-certs, and other options like PowerShell and OpenSSL.

You can then validate that the certificate will load using an example such as an ASP.NET Core app hosted in a container.

Prerequisites

In the sample, you can utilize either .NET Core 3.1 or .NET 5.

For dotnet dev-certs, be sure to have the appropriate version of .NET installed:

This sample requires Docker 17.06 or later of the Docker client.

Prepare sample app

You'll need to prepare the sample app depending on which runtime you'd like to use for testing, either .NET Core 3.1 or .NET 5.

For this guide, you'll use a sample app and make changes where appropriate.

.NET Core 3.1 sample app

Openssl

Get the sample app.

Navigate to the repository locally and open up the workspace in an editor.

Note

If you're looking to use dotnet publish parameters to trim the deployment, you should make sure that the appropriate dependencies are included for supporting SSL certificates.Update the dotnet-dockersamplesaspnetappaspnetapp.csproj to ensure that the appropriate assemblies are included in the container. For reference, check how to update the .csproj file to support ssl certificates when using trimming for self-contained deployments.

Make sure the aspnetapp.csproj includes the appropriate target framework:

Modify the Dockerfile to make sure the runtime points to .NET Core 3.1:

Make sure you're pointing to the sample app.

Build the container for testing locally.

.NET 5 sample app

For this guide, the sample aspnetapp should be checked for .NET 5.

Check sample app Dockerfile is using .NET 5.

Depending on the host OS, the ASP.NET runtime may need to be updated. For example, changing from mcr.microsoft.com/dotnet/aspnet:5.0-nanoservercore-2009 AS runtime to mcr.microsoft.com/dotnet/aspnet:5.0-windowsservercore-ltsc2019 AS runtime in the Dockerfile will help with targeting the appropriate Windows runtime.

For example, this will help with testing the certificates on Windows:

If we're testing the certificates on Linux, you can use the existing Dockerfile.

Make sure the aspnetapp.csproj includes the appropriate target framework:

Note

If you want to use dotnet publish parameters to trim the deployment, make sure that the appropriate dependencies are included for supporting SSL certificates.Update the dotnet-dockersamplesaspnetappaspnetapp.csproj to ensure that the appropriate assemblies are included in the container. For reference, check how to update the .csproj file to support ssl certificates when using trimming for self-contained deployments.

Make sure you're pointing to the sample app.

Build the container for testing locally.

Create a self-signed certificate

You can create a self-signed certificate:

With dotnet dev-certs

You can use dotnet dev-certs to work with self-signed certificates. This example uses a PowerShell console.

Note

The certificate name, in this case aspnetapp.pfx must match the project assembly name. crypticpassword is used as a stand-in for a password of your own choosing. If console returns 'A valid HTTPS certificate is already present.', a trusted certificate already exists in your store. It can be exported using MMC Console.

Configure application secrets, for the certificate:

Note

Note: The password must match the password used for the certificate.

Run the container image with ASP.NET Core configured for HTTPS:

Once the application starts, navigate to https://localhost:8001 in your web browser.

Clean up

If the secrets and certificates are not in use, be sure to clean them up.

With PowerShell

You can use PowerShell to generate self-signed certificates. The PKI Client can be used to generate a self-signed certificate.

The certificate will be generated, but for the purposes of testing, should be placed in a cert store for testing in a browser.

At this point, the certificates should be viewable from an MMC snap-in.

You can run the sample container in Windows Subsystem for Linux (WSL):

Note

Note that with the volume mount the file path could be handled differently based on host. For example, in WSL we may replace /c/certs with /mnt/c/certs.

If you're using the container built earlier for Windows, the run command would look like the following:

Once the application is up, navigate to contoso.com:8001 in a browser.

Be sure that the host entries are updated for contoso.com to answer on the appropriate ip address (for example 127.0.0.1). If the certificate isn't recognized, make sure that the certificate that is loaded with the container is also trusted on the host, and that there's appropriate SAN / DNS entries for contoso.com.

Clean up

With OpenSSL

You can use OpenSSL to create self-signed certificates. This example will use WSL / Ubuntu and a bash shell with OpenSSL.

This will generate a .crt and a .key.

To get a .pfx, use the following command:

Note

The .aspnetcore 3.1 example will use .pfx and a password. Starting with the .net 5 runtime, Kestrel can also take .crt and PEM-encoded .key files.

Depending on the host os, the certificate will need to be trusted. On a Linux host, 'trusting' the certificate is different and distro dependent.

For the purposes of this guide, here's an example in Windows using PowerShell:

For .NET Core 3.1, run the following command in WSL:

Starting with .NET 5, Kestrel can take the .crt and PEM-encoded .key files. You can run the sample with the following command for .NET 5:

Note

Note that in WSL, the volume mount path may change depending on the configuration.

For .NET Core 3.1 in Windows, run the following command in Powershell:

For .NET 5 in Windows, run the following command in PowerShell:

Once the application is up, navigate to contoso.com:8001 in a browser.

Be sure that the host entries are updated for contoso.com to answer on the appropriate ip address (for example 127.0.0.1). If the certificate isn't recognized, make sure that the certificate that is loaded with the container is also trusted on the host, and that there's appropriate SAN / DNS entries for contoso.com.

Clean up

Be sure to clean up the self-signed certificates once done testing.

Openssl Wildcard Certificate

-->

The Application Gateway v2 SKU introduces the use of Trusted Root Certificates to allow backend servers. This removes authentication certificates that were required in the v1 SKU. The root certificate is a Base-64 encoded X.509(.CER) format root certificate from the backend certificate server. It identifies the root certificate authority (CA) that issued the server certificate and the server certificate is then used for the TLS/SSL communication.

Application Gateway trusts your website's certificate by default if it's signed by a well-known CA (for example, GoDaddy or DigiCert). You don't need to explicitly upload the root certificate in that case. For more information, see Overview of TLS termination and end to end TLS with Application Gateway. However, if you have a dev/test environment and don't want to purchase a verified CA signed certificate, you can create your own custom CA and create a self-signed certificate with it.

Note

Self-signed certificates are not trusted by default and they can be difficult to maintain. Also, they may use outdated hash and cipher suites that may not be strong. For better security, purchase a certificate signed by a well-known certificate authority.

In this article, you will learn how to:

  • Create your own custom Certificate Authority
  • Create a self-signed certificate signed by your custom CA
  • Upload a self-signed root certificate to an Application Gateway to authenticate the backend server

Prerequisites

  • OpenSSL on a computer running Windows or Linux

    While there could be other tools available for certificate management, this tutorial uses OpenSSL. You can find OpenSSL bundled with many Linux distributions, such as Ubuntu.

  • A web server

    For example, Apache, IIS, or NGINX to test the certificates.

  • An Application Gateway v2 SKU

    If you don't have an existing application gateway, see Quickstart: Direct web traffic with Azure Application Gateway - Azure portal.

Create a root CA certificate

Create your root CA certificate using OpenSSL.

Create the root key

  1. Sign in to your computer where OpenSSL is installed and run the following command. This creates a password protected key.

  2. At the prompt, type a strong password. For example, at least nine characters, using upper case, lower case, numbers, and symbols.

Create a Root Certificate and self-sign it

  1. Use the following commands to generate the csr and the certificate.

    The previous commands create the root certificate. You'll use this to sign your server certificate.

  2. When prompted, type the password for the root key, and the organizational information for the custom CA such as Country/Region, State, Org, OU, and the fully qualified domain name (this is the domain of the issuer).

Create a server certificate

Next, you'll create a server certificate using OpenSSL.

Create the certificate's key

Use the following command to generate the key for the server certificate.

Openssl Self Signed Wildcard Certificate Download

Create the CSR (Certificate Signing Request)

The CSR is a public key that is given to a CA when requesting a certificate. The CA issues the certificate for this specific request.

Note

The CN (Common Name) for the server certificate must be different from the issuer's domain. For example, in this case, the CN for the issuer is www.contoso.com and the server certificate's CN is www.fabrikam.com.

Openssl Self Signed Wildcard Certificate
  1. Use the following command to generate the CSR:

  2. When prompted, type the password for the root key, and the organizational information for the custom CA: Country/Region, State, Org, OU, and the fully qualified domain name. This is the domain of the website and it should be different from the issuer.

Generate the certificate with the CSR and the key and sign it with the CA's root key

  1. Use the following command to create the certificate:

Verify the newly created certificate

  1. Use the following command to print the output of the CRT file and verify its content:

  2. Verify the files in your directory, and ensure you have the following files:

    • contoso.crt
    • contoso.key
    • fabrikam.crt
    • fabrikam.key

Configure the certificate in your web server's TLS settings

In your web server, configure TLS using the fabrikam.crt and fabrikam.key files. If your web server can't take two files, you can combine them to a single .pem or .pfx file using OpenSSL commands.

IIS

For instructions on how to import certificate and upload them as server certificate on IIS, see HOW TO: Install Imported Certificates on a Web Server in Windows Server 2003.

For TLS binding instructions, see How to Set Up SSL on IIS 7.

Apache

The following configuration is an example virtual host configured for SSL in Apache:

NGINX

The following configuration is an example NGINX server block with TLS configuration:

Access the server to verify the configuration

  1. Add the root certificate to your machine's trusted root store. When you access the website, ensure the entire certificate chain is seen in the browser.

    Note

    It's assumed that DNS has been configured to point the web server name (in this example, www.fabrikam.com) to your web server's IP address. If not, you can edit the hosts file to resolve the name.

  2. Browse to your website, and click the lock icon on your browser's address box to verify the site and certificate information.

Verify the configuration with OpenSSL

Or, you can use OpenSSL to verify the certificate.

Upload the root certificate to Application Gateway's HTTP Settings

To upload the certificate in Application Gateway, you must export the .crt certificate into a .cer format Base-64 encoded. Since .crt already contains the public key in the base-64 encoded format, just rename the file extension from .crt to .cer.

Azure portal

To upload the trusted root certificate from the portal, select the HTTP Settings and choose the HTTPS protocol.

Azure PowerShell

Openssl Generate Self Signed Certificate

Or, you can use Azure CLI or Azure PowerShell to upload the root certificate. The following code is an Azure PowerShell sample.

Note

The following sample adds a trusted root certificate to the application gateway, creates a new HTTP setting and adds a new rule, assuming the backend pool and the listener exist already.

Verify the application gateway backend health

  1. Click the Backend Health view of your application gateway to check if the probe is healthy.
  2. You should see that the Status is Healthy for the HTTPS probe.

Create Self Signed Certificate Openssl

Next steps

To learn more about SSLTLS in Application Gateway, see Overview of TLS termination and end to end TLS with Application Gateway.