{
    "Version": "2012-10-17",
    "Id": "PolicyForCredentials",
    "Statement": [
        {
            "Sid": "Allow-production-VPC-to-getObject",
            "Effect": "Allow",
            "Principal": "*",
            "Action": "s3:getObject",
            "Resource": "arn:aws:s3:::<bucket name>/*",
            "Condition": {
                "StringEquals": {
                    "aws:sourceVpce": "上で作ったVPCエンドポイントID"
                }
            }
        }
    ]
}