prowler/checks/check_extra789

#!/usr/bin/env bash

# Prowler - the handy cloud security tool (copyright 2020) by Toni de la Fuente
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may not
# use this file except in compliance with the License. You may obtain a copy
# of the License at http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software distributed
# under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
# CONDITIONS OF ANY KIND, either express or implied. See the License for the
# specific language governing permissions and limitations under the License.

CHECK_ID_extra789="7.89"
CHECK_TITLE_extra789="[extra789] Find trust boundaries in VPC endpoint services connections"
CHECK_SCORED_extra789="NOT_SCORED"
CHECK_TYPE_extra789="EXTRA"
CHECK_ALTERNATE_extra789="extra789"

extra789(){
    TRUSTED_ACCOUNT_IDS=$( echo "${ACCOUNT_NUM} ${GROUP_TRUSTBOUNDARIES_TRUSTED_ACCOUNT_IDS}" | xargs )
    
    for regx in ${REGIONS}; do
        ENDPOINT_SERVICES_IDS=$(${AWSCLI} ec2 describe-vpc-endpoint-services \
                                ${PROFILE_OPT} \
                                --query "ServiceDetails[?Owner=='${ACCOUNT_NUM}'].ServiceId" \
                                --region ${regx} \
                                --output text | xargs
                                )

        for ENDPOINT_SERVICE_ID in ${ENDPOINT_SERVICES_IDS}; do
    
            ENDPOINT_CONNECTION_LIST=$(${AWSCLI} ec2 describe-vpc-endpoint-connections \
                                        ${PROFILE_OPT} \
                                        --query "VpcEndpointConnections[?VpcEndpointState=='available'].VpcEndpointOwner" \
                                        --region ${regx} \
                                        --output text | xargs
                                        )
            
            for ENDPOINT_CONNECTION in ${ENDPOINT_CONNECTION_LIST}; do
                for ACCOUNT_ID in ${TRUSTED_ACCOUNT_IDS}; do
                    if [[ "${ACCOUNT_ID}" == "${ENDPOINT_CONNECTION}" ]]; then
                        textPass "${regx}: Found trusted account in VPC endpoint service connection ${ENDPOINT_CONNECTION}" "${regx}"
                        # Algorithm: 
                        # Remove all trusted ACCOUNT_IDs from ENDPOINT_CONNECTION_LIST.
                        # As a result, the ENDPOINT_CONNECTION_LIST finally contains only unknown/untrusted account ids.
                        ENDPOINT_CONNECTION_LIST=("${ENDPOINT_CONNECTION_LIST[@]/$ENDPOINT_CONNECTION}") # remove hit from whitelist
                    fi
                done
            done

            for UNTRUSTED_CONNECTION in ${ENDPOINT_CONNECTION_LIST}; do
                textFail "${regx}: Found untrusted account in VPC endpoint service connection ${UNTRUSTED_CONNECTION}" "${regx}"
            done
        done  
    done
}