Amazon EC2 Instance Connect enables system administrators to publish one-time use SSH public keys to EC2, providing users a simple and secure way to connect to their instances.
curl \ -H "Authorization: $API_KEY" \ http://ec2-instance-connect.us-east-1.amazonaws.com/#X-Amz-Target=AWSEC2InstanceConnectService.SendSSHPublicKey
curl \ -H "Authorization: $API_KEY" \ http://ec2-instance-connect.us-east-1.amazonaws.com/#X-Amz-Target=AWSEC2InstanceConnectService.SendSerialConsoleSSHPublicKey