#!/usr/bin/env bash

# Prowler - the handy cloud security tool (copyright 2018) 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_extra725="7.25"
CHECK_TITLE_extra725="[extra725] Check if S3 buckets have Object-level logging enabled in CloudTrail"
CHECK_SCORED_extra725="NOT_SCORED"
CHECK_CIS_LEVEL_extra725="EXTRA"
CHECK_SEVERITY_extra725="Medium"
CHECK_ASFF_RESOURCE_TYPE_extra725="AwsS3Bucket"
CHECK_ALTERNATE_check725="extra725"
CHECK_SERVICENAME_extra725="s3"
CHECK_RISK_extra725='If logs are not enabled; monitoring of service use and threat analysis is not possible.'
CHECK_REMEDIATION_extra725='Enable logs. Create an S3 lifecycle policy. Define use cases; metrics and automated responses where applicable.'
CHECK_DOC_extra725='https://docs.aws.amazon.com/AmazonS3/latest/userguide/enable-cloudtrail-logging-for-s3.html'
CHECK_CAF_EPIC_extra725='Logging and Monitoring'

# per Object-level logging is not configured at Bucket level but at CloudTrail trail level
extra725(){
  # "Check if S3 buckets have Object-level logging enabled in CloudTrail "
  LIST_OF_BUCKETS=$($AWSCLI s3api list-buckets $PROFILE_OPT --region $REGION --query 'Buckets[*].{Name:Name}' --output text 2>&1)
  if [[ $(echo "$LIST_OF_BUCKETS" | grep AccessDenied) ]]; then
    textInfo "$REGION: Access Denied trying to list buckets"
    return
  fi
  LIST_OF_TRAILS=$($AWSCLI cloudtrail describe-trails $PROFILE_OPT --region $REGION --query 'trailList[].TrailARN' --output text 2>&1)
  if [[ $(echo "$LIST_OF_TRAILS" | grep AccessDenied) ]]; then
    textInfo "$REGION: Access Denied trying to describe trails"
    return
  fi
  if [[ $LIST_OF_BUCKETS ]]; then
    for bucketName in $LIST_OF_BUCKETS; do
      if [[ $LIST_OF_TRAILS ]]; then
        BUCKET_ENABLED_TRAILS=()

        for trail in $LIST_OF_TRAILS; do
          BUCKET_ENABLED_IN_TRAIL=$($AWSCLI cloudtrail get-event-selectors --region $REGION $PROFILE_OPT --trail-name $trail --query "EventSelectors[*].DataResources[?Type == \`AWS::S3::Object\`].Values" --output text |xargs -n1| grep -E "^arn:${AWS_PARTITION}:s3:::$bucketName/\S*$|^arn:${AWS_PARTITION}:s3$|^arn:${AWS_PARTITION}:s3:::$")
          if [[ $BUCKET_ENABLED_IN_TRAIL ]]; then
            BUCKET_ENABLED_TRAILS+=($trail)
          fi
        done

        if [[ ${#BUCKET_ENABLED_TRAILS[@]} -gt 0 ]]; then
          for trail in "${BUCKET_ENABLED_TRAILS[@]}"; do
            textPass "$REGION: S3 bucket $bucketName has Object-level logging enabled in trail $trail" "$REGION" "$bucketName"
          done
        else
          textFail "$REGION: S3 bucket $bucketName has Object-level logging disabled" "$REGION" "$bucketName"
        fi

      else
        textFail "$REGION: S3 bucket $bucketName is not being recorded no CloudTrail found!" "$REGION" "$bucketName"
      fi
    done
  else
    textInfo "$REGION: No S3 buckets found" "$REGION"
  fi
}