#!/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.

# Checks that the correct mode (json-asff) has been specified if wanting to send check output to AWS Security Hub
# and that Security Hub is enabled in the chosen region
checkSecurityHubCompatibility(){
  local regx
  if [[ "${MODE}" != "json-asff" ]]; then
    echo -e "\n$RED ERROR!$NORMAL Output can only be sent to Security Hub when the output mode is json-asff, i.e. -M json-asff -S\n"
    EXITCODE=1
    exit $EXITCODE
  fi
  for regx in $REGIONS; do
    SECURITY_HUB_ENABLED=$($AWSCLI securityhub --region "$regx" $PROFILE_OPT describe-hub)
    if [[ -z "${SECURITY_HUB_ENABLED}" ]]; then
      echo -e "\n$RED ERROR!$NORMAL Security Hub is not enabled in $regx. Enable it by calling '$AWSCLI securityhub --region $regx $PROFILE_OPT enable-security-hub'\n"
      EXITCODE=1
      exit $EXITCODE
    fi
  done
  # Get unresolved findings
  SECURITY_HUB_PREVIOUS_FINDINGS=$($AWSCLI securityhub --region "$regx" $PROFILE_OPT get-findings --filters '{"GeneratorId":[{"Value": "prowler-","Comparison":"PREFIX"}],"WorkflowStatus":[{"Value": "RESOLVED","Comparison":"NOT_EQUALS"}]}' | jq -r ".Findings[] | {Id, GeneratorId, Workflow, Compliance}"| jq -cs)
}

resolveSecurityHubPreviousFails(){
  # Move previous findings to Workflow to RESOLVED (as prowler didn't re-detect them)
  PREVIOUS_FAILED_IDS=$(echo $SECURITY_HUB_PREVIOUS_FINDINGS | jq -c --arg parn "$product_arn" '.[] | select(.Compliance.Status==FAILED) | map({"Id": .Id, ProductArn: $parn} )');
  BATCH_UPDATE_RESULT=$($AWSCLI securityhub --region "$region" $PROFILE_OPT batch-update-findings --finding-identifiers "${PREVIOUS_FAILED_IDS}" --workflow '{"Status": "RESOLVED"}')

  # Check for success if updated
  if [[ ! -z "${BATCH_UPDATE_RESULT}" ]] && ! jq -e '.ProcessedFindings >= 1' <<< "${BATCH_UPDATE_RESULT}" > /dev/null 2>&1; then
    echo -e "\n$RED ERROR!$NORMAL Failed to update AWS Security Hub finding\n"
  fi

}

sendToSecurityHub(){

  local findings="$1"
  local region="$2"
  local finding_id=$(echo $findings | jq -r ".Id")
  local status=$(echo $findings | jq -r ".Compliance.Status")
  local product_arn=$(echo $findings | jq -r ".ProductArn")
  local generator_id=$(echo $findings | jq -r ".GeneratorId")

  PREVIOUS_FINDING=$(echo $SECURITY_HUB_PREVIOUS_FINDINGS | jq --arg finding "$generator_id" '.[] | select((.GeneratorId==$finding))' | jq -cs)
  if [[ $PREVIOUS_FINDING != "[]" ]]; then
    # Remove from previous findings to update (using generator)
    SECURITY_HUB_PREVIOUS_FINDINGS=$(echo $SECURITY_HUB_PREVIOUS_FINDINGS | jq -s --arg finding "$generator_id" '[ .[] | select((.GeneratorId!=$finding)) ]')

    SAME_STATUS=$(echo $PREVIOUS_FINDING | jq --arg status "$status" '.[] | select(.Compliance.Status!=$status)')
    SUPPRESSED=$(echo $PREVIOUS_FINDING | jq '.[] | select(.Workflow.Status=="SUPPRESSED")')
    # If are old non-resolved findings with different status, re-import it to update with previous Id
    if [[ ! -z $SAME_STATUS && -z $SUPPRESSED ]]; then
      PREVIOUS_FINDING_ID=$(echo $PREVIOUS_FINDING | jq '.[0].Id' );
      findings =$(echo $findings | jq --arg previous_id "$PREVIOUS_FINDING_ID"  .[0].Id = previous_id)
      BATCH_IMPORT_RESULT=$($AWSCLI securityhub --region "$region" $PROFILE_OPT batch-import-findings --findings "${findings}")
    else
      PREVIOUS_FINDING_IDS=$(echo $PREVIOUS_FINDING | jq -c --arg parn "$product_arn" 'map({"Id": .Id, ProductArn: $parn} )');
      # Update to avoid being deleted after 90 dayss
      BATCH_UPDATE_RESULT=$($AWSCLI securityhub --region "$region" $PROFILE_OPT batch-update-findings --finding-identifiers "${PREVIOUS_FINDING_IDS}" --note '{"Text": "Finding re-detected by Prowler scan", "UpdatedBy": "prowler"}')
    fi
  else
    #If new, import it
    BATCH_IMPORT_RESULT=$($AWSCLI securityhub --region "$region" $PROFILE_OPT batch-import-findings --findings "${findings}")
  fi

  # Check for success if updated
  if [[ ! -z "${BATCH_UPDATE_RESULT}" ]] && ! jq -e '.ProcessedFindings >= 1' <<< "${BATCH_UPDATE_RESULT}" > /dev/null 2>&1; then
    echo -e "\n$RED ERROR!$NORMAL Failed to update AWS Security Hub finding\n"
  fi

  # Check for success if imported
  if [[ ! -z "${BATCH_IMPORT_RESULT}" ]] && ! jq -e '.SuccessCount == 1' <<< "${BATCH_IMPORT_RESULT}" > /dev/null 2>&1; then
    echo -e "\n$RED ERROR!$NORMAL Failed to send check output to AWS Security Hub\n"
  fi

}