How Install an SSL certificate on File Gateway hosted on EC2

Storage Gateway uses SSL/TLS (Secure Socket Layers/Transport Layer Security) to encrypt data that is transferred between your gateway appliance and AWS storage. By default, Storage Gateway uses Amazon S3-Managed encryption keys (SSE-S3) to server-side encrypt all data it stores in Amazon S3. You have an option to use the Storage Gateway API to configure your gateway to encrypt data stored in the cloud using server-side encryption with AWS Key Management Service (SSE-KMS) keys.

See https://docs.aws.amazon.com/filegateway/latest/files3/encryption.html

For importing key material into AWS KMS, see https://docs.aws.amazon.com/kms/latest/developerguide/importing-keys.html