AWS Private CA VPC endpoints (AWS PrivateLink)

You can create a private connection between your VPC and AWS Private CA by configuring an interface VPC endpoint. Interface endpoints are powered by AWS PrivateLink, a technology for privately accessing AWS Private CA API operations. AWS PrivateLink routes all network traffic between your VPC and AWS Private CA through the Amazon network, avoiding exposure on the open internet. Each VPC endpoint is represented by one or more elastic network interfaces with private IP addresses in your VPC subnets.

The interface VPC endpoint connects your VPC directly to AWS Private CA without an internet gateway, NAT device, VPN connection, or AWS Direct Connect connection. The instances in your VPC don't need public IP addresses to communicate with the AWS Private CA API.

To use AWS Private CA through your VPC, you must connect from an instance that is inside the VPC. Alternatively, you can connect your private network to your VPC by using an AWS Virtual Private Network (AWS VPN) or AWS Direct Connect. For information about AWS VPN, see VPN Connections in the Amazon VPC User Guide. For information about AWS Direct Connect, see Creating a Connection in the AWS Direct Connect User Guide.

AWS Private CA does not require the use of AWS PrivateLink, but we recommend it as an additional layer of security. For more information about AWS PrivateLink and VPC endpoints, see Accessing Services Through AWS PrivateLink.

Considerations for AWS Private CA VPC endpoints

Before you set up interface VPC endpoints for AWS Private CA, be aware of the following considerations:

AWS Private CA API currently supports VPC endpoints in the following AWS Regions:

Creating the VPC endpoints for AWS Private CA

You can create a VPC endpoint for the AWS Private CA service using either the VPC console at https://console.aws.amazon.com/vpc/ or the AWS Command Line Interface. For more information, see the Creating an Interface Endpoint procedure in the Amazon VPC User Guide. AWS Private CA supports making calls to all of its API operations inside your VPC.

If you have enabled private DNS host names for the endpoint, then the default AWS Private CA endpoint now resolves to your VPC endpoint. For a comprehensive list of default service endpoints, see Service Endpoints and Quotas.

If you have not enabled private DNS host names, Amazon VPC provides a DNS endpoint name that you can use in the following format:

vpc-endpoint-id.acm-pca.region.vpce.amazonaws.com

For more information, see AWS Private CA VPC endpoints (AWS PrivateLink) in the Amazon VPC User Guide.

Create a VPC endpoint policy for AWS Private CA

You can create a policy for Amazon VPC endpoints for AWS Private CA to specify the following:

For more information, see Controlling Access to Services with VPC Endpoints in the Amazon VPC User Guide.

Example – VPC endpoint policy for AWS Private CA actions

When attached to an endpoint, the following policy grants access for all principals to the AWS Private CA actions IssueCertificate, DescribeCertificateAuthority, GetCertificate, GetCertificateAuthorityCertificate, ListPermissions, and ListTags. The resource in each stanza is a private CA. The first stanza authorizes the creation of end-entity certificates using the specified private CA and certificate template. If you don't want to control the template being used, the Condition section is not needed. However, removing this allows all principals to create CA certificates as well as end-entity certificates.

{
      "Statement":[
         {
            "Principal":"*",
            "Effect":"Allow",
            "Action":[
               "acm-pca:IssueCertificate"
            ],
            "Resource":[
               "arn:aws:acm-pca:us-east-1:111122223333:certificate-authority/11223344-1234-1122-2233-112233445566"
            ],
            "Condition":{
               "StringEquals":{
                  "acm-pca:TemplateArn":"arn:aws:acm-pca:::template/EndEntityCertificate/V1"
               }
            }
         },
         {
            "Principal":"*",
            "Effect":"Allow",
            "Action":[
               "acm-pca:DescribeCertificateAuthority",
               "acm-pca:GetCertificate",
               "acm-pca:GetCertificateAuthorityCertificate",
               "acm-pca:ListPermissions",
               "acm-pca:ListTags"
            ],
            "Resource":[
               "arn:aws:acm-pca:us-east-1:111122223333:certificate-authority/11223344-1234-1122-2233-112233445566"
            ]
         }
      ]
   }