Fine-Grained Access Control for AI APIs with AWS Cognito

Question

Pulumi · Accepted Answer

To implement fine-grained access control for AI APIs with AWS Cognito, we will create a user pool to manage users, an identity pool to federate user identities and provide them with AWS credentials, and set up roles and permissions accordingly. For fine-grained access control, we assign IAM roles with specific policies to users or groups of users.

Here's how the setup works:
1. **User Pool**: This is a user directory in Amazon Cognito. With a user pool, you can allow users to sign in to your app through Cognito, or federate through a third-party identity provider (IdP).
   
2. **Identity Pool**: Amazon Cognito Identity Pools (Federated Identities) enable you to create unique identities for users and federate them with identity providers. With an identity pool, you can obtain temporary, limited-privilege AWS credentials to access other AWS services.

3. **IAM Roles**: AWS Identity and Access Management (IAM) roles let you define a set of permissions for making AWS service requests. IAM roles are not associated with a specific user or group but are intended to be assumable by anyone who needs them.

4. **Role Attachments**: Identity Pool Role Attachments are used to define rules for mapping users to roles. You can assign different roles to authenticated and unauthenticated users or based on a match with a user's attributes.

Below is a Pulumi program in Python that sets up fine-grained access control using AWS Cognito for AI APIs. The program will:

- Create a Cognito User Pool where your users can sign up and sign in.
- Create a Cognito Identity Pool, which allows users to authenticate with the user pool and receive AWS credentials.
- Assign IAM roles to authenticated and unauthenticated users with specific policies for AI APIs.

```python
import pulumi
import pulumi_aws as aws

# Create a Cognito User Pool
user_pool = aws.cognito.UserPool("aiApiUserPool",
    name="aiApiUserPool",
    # Configuring attributes and other settings as necessary
)

# Create an identity pool with both authenticated and unauthenticated roles
identity_pool = aws.cognito.IdentityPool("aiApiIdentityPool",
    allow_unauthenticated_identities=True,  # true if you want to allow unauthenticated access
    cognito_identity_providers=[{
        "clientId": user_pool.client_id,
        "providerName": user_pool.endpoint,
    }],
    identity_pool_name="aiApiIdentityPool",
)

# Create IAM roles and policies for authenticated and unauthenticated users
# Replace 'your_policy_document' with the actual policy document JSON string.
auth_role_policy = aws.iam.Policy("authRolePolicy",
    policy="""{
        "Version": "2012-10-17",
        "Statement": [
            {
                "Effect": "Allow",
                "Action": [
                    "ai-service:SomeUserSpecificAction",  # Specify the AI service permissions
                ],
                "Resource": "*"
            }
        ]
    }"""
)

unauth_role_policy = aws.iam.Policy("unauthRolePolicy",
    policy="""{
        "Version": "2012-10-17",
        "Statement": [
            {
                "Effect": "Allow",
                "Action": [
                    "ai-service:SomeGuestSpecificAction",  # Specify the AI service permissions
                ],
                "Resource": "*"
            }
        ]
    }"""
)

# Create IAM roles for authenticated and unauthenticated users
auth_role = aws.iam.Role("authRole",
    assume_role_policy=identity_pool.assume_role_policy_auth_json,
)

unauth_role = aws.iam.Role("unauthRole",
    assume_role_policy=identity_pool.assume_role_policy_unauth_json,
)

# Attach the policies to the roles
aws.iam.RolePolicyAttachment("authRolePolicyAttachment",
    role=auth_role.name,
    policy_arn=auth_role_policy.arn,
)

aws.iam.RolePolicyAttachment("unauthRolePolicyAttachment",
    role=unauth_role.name,
    policy_arn=unauth_role_policy.arn,
)

# Attach the roles to the identity pool
role_attachment = aws.cognito.IdentityPoolRoleAttachment("aiApiIdentityPoolRoleAttachment",
    identity_pool_id=identity_pool.id,
    roles={
        "authenticated": auth_role.arn,
        "unauthenticated": unauth_role.arn,
    },
)

# Export some values of the resources created
pulumi.export("user_pool_id", user_pool.id)
pulumi.export("identity_pool_id", identity_pool.id)
pulumi.export("auth_role_arn", auth_role.arn)
pulumi.export("unauth_role_arn", unauth_role.arn)
```

In this program, the `ai-service:SomeUserSpecificAction` and `ai-service:SomeGuestSpecificAction` are placeholders where you would specify the actual AI API actions you want to permit for authenticated and unauthenticated users respectively. Make sure to replace these with the specific AWS service actions you will be controlling access to.

The `assume_role_policy` should be a JSON policy document string that allows users from your Cognito Identity Pool to assume the authenticated and unauthenticated roles.

Make sure to replace the policy documents in `auth_role_policy` and `unauth_role_policy` IAM policy resources with your own policies to grant the necessary permissions for your AI APIs. These policies will manage what resources and actions your users are permitted to access or execute on AWS.

By exporting the User Pool ID, Identity Pool ID, and the role ARNs, you can easily reference these resources elsewhere in your infrastructure as code, or pass them to your application's backend to assume the appropriate roles when interacting with your AI APIs.