Amazon API Gateway identity-based policy examples

By default, IAM users and roles don't have permission to create or modify API Gateway resources. They also can't perform tasks using the AWS Management Console, AWS CLI, or AWS SDKs. An IAM administrator must create IAM policies that grant users and roles permission to perform specific API operations on the specified resources they need. The administrator must then attach those policies to the IAM users or groups that require those permissions.

For information about how to create IAM policies, see Creating Policies on the JSON Tab in the IAM User Guide. For information about the actions, resources, and conditions specific to API Gateway, see Actions, resources, and condition keys for Amazon API Gateway Management and Actions, resources, and condition keys for Amazon API Gateway Management V2.

Policy best practices

Identity-based policies determine whether someone can create, access, or delete API Gateway resources in your account. These actions can incur costs for your AWS account. When you create or edit identity-based policies, follow these guidelines and recommendations:

• Get started with AWS managed policies and move toward least-privilege permissions – To get started granting permissions to your users and workloads, use the AWS managed policies that grant permissions for many common use cases. They are available in your AWS account. We recommend that you reduce permissions further by defining AWS customer managed policies that are specific to your use cases. For more information, see AWS managed policies or AWS managed policies for job functions in the IAM User Guide.

• Apply least-privilege permissions – When you set permissions with IAM policies, grant only the permissions required to perform a task. You do this by defining the actions that can be taken on specific resources under specific conditions, also known as least-privilege permissions. For more information about using IAM to apply permissions, see Policies and permissions in IAM in the IAM User Guide.

• Use conditions in IAM policies to further restrict access – You can add a condition to your policies to limit access to actions and resources. For example, you can write a policy condition to specify that all requests must be sent using SSL. You can also use conditions to grant access to service actions if they are used through a specific AWS service, such as AWS CloudFormation. For more information, see IAM JSON policy elements: Condition in the IAM User Guide.

• Use IAM Access Analyzer to validate your IAM policies to ensure secure and functional permissions – IAM Access Analyzer validates new and existing policies so that the policies adhere to the IAM policy language (JSON) and IAM best practices. IAM Access Analyzer provides more than 100 policy checks and actionable recommendations to help you author secure and functional policies. For more information, see IAM Access Analyzer policy validation in the IAM User Guide.

• Require multi-factor authentication (MFA) – If you have a scenario that requires IAM users or a root user in your AWS account, turn on MFA for additional security. To require MFA when API operations are called, add MFA conditions to your policies. For more information, see Configuring MFA-protected API access in the IAM User Guide.

For more information about best practices in IAM, see Security best practices in IAM in the IAM User Guide.

Allow users to view their own permissions

This example shows how you might create a policy that allows IAM users to view the inline and managed policies that are attached to their user identity. This policy includes permissions to complete this action on the console or programmatically using the AWS CLI or AWS API.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "ViewOwnUserInfo",
            "Effect": "Allow",
            "Action": [
                "iam:GetUserPolicy",
                "iam:ListGroupsForUser",
                "iam:ListAttachedUserPolicies",
                "iam:ListUserPolicies",
                "iam:GetUser"
            ],
            "Resource": ["arn:aws:iam::*:user/${aws:username}"]
        },
        {
            "Sid": "NavigateInConsole",
            "Effect": "Allow",
            "Action": [
                "iam:GetGroupPolicy",
                "iam:GetPolicyVersion",
                "iam:GetPolicy",
                "iam:ListAttachedGroupPolicies",
                "iam:ListGroupPolicies",
                "iam:ListPolicyVersions",
                "iam:ListPolicies",
                "iam:ListUsers"
            ],
            "Resource": "*"
        }
    ]
}

Simple read permissions

This example policy gives a user permission to get information about all of the resources of an HTTP or WebSocket API with the identifier of a123456789 in the AWS Region of us-east-1. The resource arn:aws:apigateway:us-east-1::/apis/a123456789/* includes all sub-resources of the API such as authorizers and deployments.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "apigateway:GET"
      ],
      "Resource": [
        "arn:aws:apigateway:us-east-1::/apis/a123456789/*"
      ]
    }
  ]
}

Create only REQUEST or JWT authorizers

This example policy allows a user to create APIs with only REQUEST or JWT authorizers, including through import. In the Resource section of the policy, arn:aws:apigateway:us-east-1::/apis/?????????? requires that resources have a maximum of 10 characters, which excludes sub-resources of an API. This example uses ForAllValues in the Condition section because users can create multiple authorizers at once by importing an API.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "OnlyAllowSomeAuthorizerTypes",
      "Effect": "Allow",
      "Action": [
        "apigateway:PUT",
        "apigateway:POST",
        "apigateway:PATCH"
      ],
      "Resource": [
        "arn:aws:apigateway:us-east-1::/apis",
        "arn:aws:apigateway:us-east-1::/apis/??????????",
        "arn:aws:apigateway:us-east-1::/apis/*/authorizers",
        "arn:aws:apigateway:us-east-1::/apis/*/authorizers/*"
      ],
      "Condition": {
        "ForAllValues:StringEqualsIfExists": {
          "apigateway:Request/AuthorizerType": [
            "REQUEST",
            "JWT"
          ]
        }
      }
    }
  ]
}

Require that the default execute-api endpoint is disabled

This example policy allows users to create, update or import an API, with the requirement that DisableExecuteApiEndpoint is true. When DisableExecuteApiEndpoint is true, clients can't use the default execute-api endpoint to invoke an API.

We use the BoolIfExists condition to handle a call to update an API that doesn't have the DisableExecuteApiEndpoint condition key populated. When a user attempts to create or import an API, the DisableExecuteApiEndpoint condition key is always populated.

Because the apis/* resource also captures sub resources such as authorizers or methods, we explicitly scope it to just APIs with a Deny statement.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "DisableExecuteApiEndpoint",
      "Effect": "Allow",
      "Action": [
        "apigateway:PATCH",
        "apigateway:POST",
        "apigateway:PUT"
      ],
      "Resource": [
        "arn:aws:apigateway:us-east-1::/apis",
        "arn:aws:apigateway:us-east-1::/apis/*"
      ],
      "Condition": {
        "BoolIfExists": {
          "apigateway:Request/DisableExecuteApiEndpoint": true
        }
      }
    },
    {
      "Sid": "ScopeDownToJustApis",
      "Effect": "Deny",
      "Action": [
        "apigateway:PATCH",
        "apigateway:POST",
        "apigateway:PUT"
      ],
      "Resource": [
        "arn:aws:apigateway:us-east-1::/apis/*/*"
      ]
    }
  ]
}

Allow users to create or update only private REST APIs

This example policy uses condition keys to require that a user creates only PRIVATE APIs, and to prevent updates that might change an API from PRIVATE to another type, such as REGIONAL.

We use ForAllValues to require that every EndpointType added to an API is PRIVATE. We use a resource condition key to allow any update to an API as long as it's PRIVATE. ForAllValues applies only if a condition key is present.

We use the non-greedy matcher (?) to explicitly match against API IDs to prevent allowing non-API resources such as authorizers.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "ScopePutToPrivateApis",
            "Effect": "Allow",
            "Action": [
                "apigateway:PUT"
            ],
            "Resource": [
                "arn:aws:apigateway:us-east-1::/restapis",
                "arn:aws:apigateway:us-east-1::/restapis/??????????"
            ],
            "Condition": {
                "ForAllValues:StringEquals": {
                    "apigateway:Resource/EndpointType": "PRIVATE"
                }
            }
        },
        {
            "Sid": "ScopeToPrivateApis",
            "Effect": "Allow",
            "Action": [
                "apigateway:DELETE",
                "apigateway:PATCH",
                "apigateway:POST"
            ],
            "Resource": [
                "arn:aws:apigateway:us-east-1::/restapis",
                "arn:aws:apigateway:us-east-1::/restapis/??????????"
            ],
            "Condition": {
                "ForAllValues:StringEquals": {
                    "apigateway:Request/EndpointType": "PRIVATE",
                    "apigateway:Resource/EndpointType": "PRIVATE"
                }
            }
        },
        {
            "Sid": "AllowResourcePolicyUpdates",
            "Effect": "Allow",
            "Action": [
                "apigateway:UpdateRestApiPolicy"
            ],
            "Resource": [
                "arn:aws:apigateway:us-east-1::/restapis/*"
            ]
        }
    ]
}

Require that API routes have authorization

This policy causes attempts to create or update a route (including through import) to fail if the route has no authorization. ForAnyValue evaluates to false if the key is not present, such as when a route is not being created or updated. We use ForAnyValue because multiple routes can be created through import.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "AllowUpdatesOnApisAndRoutes",
      "Effect": "Allow",
      "Action": [
        "apigateway:POST",
        "apigateway:PATCH",
        "apigateway:PUT"
      ],
      "Resource": [
        "arn:aws:apigateway:us-east-1::/apis",
        "arn:aws:apigateway:us-east-1::/apis/??????????",
        "arn:aws:apigateway:us-east-1::/apis/*/routes",
        "arn:aws:apigateway:us-east-1::/apis/*/routes/*"
      ]
    },
    {
      "Sid": "DenyUnauthorizedRoutes",
      "Effect": "Deny",
      "Action": [
        "apigateway:POST",
        "apigateway:PATCH",
        "apigateway:PUT"
      ],
      "Resource": [
        "arn:aws:apigateway:us-east-1::/apis",
        "arn:aws:apigateway:us-east-1::/apis/*"
      ],
      "Condition": {
        "ForAnyValue:StringEqualsIgnoreCase": {
          "apigateway:Request/RouteAuthorizationType": "NONE"
        }
      }
    }
  ]
}

Prevent a user from creating or updating a VPC link

This policy prevents a user from creating or updating a VPC link. A VPC link enables you to expose resources within an Amazon VPC to clients outside of the VPC.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "DenyVPCLink",
      "Effect": "Deny",
      "Action": [
        "apigateway:POST",
        "apigateway:PUT",
        "apigateway:PATCH"
      ],
      "Resource": [
        "arn:aws:apigateway:us-east-1::/vpclinks",
        "arn:aws:apigateway:us-east-1::/vpclinks/*"
      ]
    }
  ]
}