#!/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_extra73="7.3,7.03"
CHECK_TITLE_extra73="[extra73] Ensure there are no S3 buckets open to the Everyone or Any AWS user (Not Scored) (Not part of CIS benchmark)"
CHECK_SCORED_extra73="NOT_SCORED"
CHECK_TYPE_extra73="EXTRA"
CHECK_ALTERNATE_extra703="extra73"
CHECK_ALTERNATE_check73="extra73"
CHECK_ALTERNATE_check703="extra73"

extra73(){
  textInfo "Looking for open S3 Buckets (ACLs and Policies) in all regions...  "
  ALL_BUCKETS_LIST=$($AWSCLI s3api list-buckets --query 'Buckets[*].{Name:Name}' $PROFILE_OPT --region $REGION --output text)
  for bucket in $ALL_BUCKETS_LIST; do
    BUCKET_LOCATION=$($AWSCLI s3api get-bucket-location --bucket $bucket $PROFILE_OPT --region $REGION --output text)
    if [[ "None" == $BUCKET_LOCATION ]]; then
      BUCKET_LOCATION="us-east-1"
    fi
    if [[ "EU" == $BUCKET_LOCATION ]]; then
      BUCKET_LOCATION="eu-west-1"
    fi
    # check if AllUsers is in the ACL as Grantee
    CHECK_BUCKET_ALLUSERS_ACL=$($AWSCLI s3api get-bucket-acl $PROFILE_OPT --region $BUCKET_LOCATION --bucket $bucket --query "Grants[?Grantee.URI == 'http://acs.amazonaws.com/groups/global/AllUsers']" --output text |grep -v GRANTEE)
    CHECK_BUCKET_ALLUSERS_ACL_SINGLE_LINE=$(echo -ne $CHECK_BUCKET_ALLUSERS_ACL)
    # check if AuthenticatedUsers is in the ACL as Grantee, they will have access with sigened URL only
    CHECK_BUCKET_AUTHUSERS_ACL=$($AWSCLI s3api get-bucket-acl $PROFILE_OPT --region $BUCKET_LOCATION --bucket $bucket --query "Grants[?Grantee.URI == 'http://acs.amazonaws.com/groups/global/AuthenticatedUsers']" --output text |grep -v GRANTEE)
    CHECK_BUCKET_AUTHUSERS_ACL_SINGLE_LINE=$(echo -ne $CHECK_BUCKET_AUTHUSERS_ACL)
    # to prevent error NoSuchBucketPolicy first clean the output controlling stderr
    TEMP_POLICY_FILE=$(mktemp -t prowler-${ACCOUNT_NUM}-${bucket}.policy.XXXXXXXXXX)
    $AWSCLI s3api get-bucket-policy $PROFILE_OPT --region $BUCKET_LOCATION --bucket $bucket --output text --query Policy > $TEMP_POLICY_FILE 2> /dev/null
    # check if the S3 policy has Principal as *
    CHECK_BUCKET_ALLUSERS_POLICY=$(cat $TEMP_POLICY_FILE | sed -e 's/[{}]/''/g' | awk -v k="text" '{n=split($0,a,","); for (i=1; i<=n; i++) print a[i]}'|awk '/Principal/ && !skip { print } { skip = /Deny/} '|grep ^\"Principal|grep \*)
    if [[ $CHECK_BUCKET_ALLUSERS_ACL || $CHECK_BUCKET_AUTHUSERS_ACL || $CHECK_BUCKET_ALLUSERS_POLICY ]];then
      if [[ $CHECK_BUCKET_ALLUSERS_ACL ]];then
        textFail "$BUCKET_LOCATION: $bucket bucket is open to the Internet (Everyone) with permissions: $CHECK_BUCKET_ALLUSERS_ACL_SINGLE_LINE" "$regx"
      fi
      if [[ $CHECK_BUCKET_AUTHUSERS_ACL ]];then
        textFail "$BUCKET_LOCATION: $bucket bucket is open to Authenticated users (Any AWS user) with permissions: $CHECK_BUCKET_AUTHUSERS_ACL_SINGLE_LINE" "$regx"
      fi
      if [[ $CHECK_BUCKET_ALLUSERS_POLICY ]];then
        textFail "$BUCKET_LOCATION: $bucket bucket policy \"may\" allow Anonymous users to perform actions (Principal: \"*\")" "$regx"
      fi
    else
      textPass "$BUCKET_LOCATION: $bucket bucket is not open" "$regx"
    fi
    rm -fr $TEMP_POLICY_FILE
  done
}

# Then implementation below makes pararel checks but can reach AWS API limits
# and eventually doesn't work as expected

# extra73(){
#   textTitle "$ID73" "$TITLE73" "NOT_SCORED" "EXTRA"
#   textNotice "Looking for open S3 Buckets (ACLs and Policies) in all regions...  "
#   ALL_BUCKETS_LIST=$($AWSCLI s3api list-buckets --query 'Buckets[*].{Name:Name}' --profile $PROFILE --region $REGION --output text)
#   for bucket in $ALL_BUCKETS_LIST; do
#     extra73Thread $bucket &
#   done
#   wait
# }
# extra73Thread(){
#   bucket=$1
#   BUCKET_LOCATION=$($AWSCLI s3api get-bucket-location --bucket $bucket --profile $PROFILE --region $REGION --output text)
#   if [[ "None" == $BUCKET_LOCATION ]]; then
#     BUCKET_LOCATION="us-east-1"
#   fi
#   if [[ "EU" == $BUCKET_LOCATION ]]; then
#     BUCKET_LOCATION="eu-west-1"
#   fi
#   # check if AllUsers is in the ACL as Grantee
#   CHECK_BUCKET_ALLUSERS_ACL=$($AWSCLI s3api get-bucket-acl --profile $PROFILE --region $BUCKET_LOCATION --bucket $bucket --query "Grants[?Grantee.URI == 'http://acs.amazonaws.com/groups/global/AllUsers']" --output text |grep -v GRANTEE)
#   CHECK_BUCKET_ALLUSERS_ACL_SINGLE_LINE=$(echo -ne $CHECK_BUCKET_ALLUSERS_ACL)
#   # check if AuthenticatedUsers is in the ACL as Grantee, they will have access with sigened URL only
#   CHECK_BUCKET_AUTHUSERS_ACL=$($AWSCLI s3api get-bucket-acl --profile $PROFILE --region $BUCKET_LOCATION --bucket $bucket --query "Grants[?Grantee.URI == 'http://acs.amazonaws.com/groups/global/AuthenticatedUsers']" --output text |grep -v GRANTEE)
#   CHECK_BUCKET_AUTHUSERS_ACL_SINGLE_LINE=$(echo -ne $CHECK_BUCKET_AUTHUSERS_ACL)
#   # to prevent error NoSuchBucketPolicy first clean the output controlling stderr
#   TEMP_POLICY_FILE=$(mktemp -t prowler-${ACCOUNT_NUM}-${bucket}.policy.XXXXXXXXXX)
#   $AWSCLI s3api get-bucket-policy --profile $PROFILE --region $BUCKET_LOCATION --bucket $bucket --output text --query Policy > $TEMP_POLICY_FILE 2> /dev/null
#   # check if the S3 policy has Principal as *
#   CHECK_BUCKET_ALLUSERS_POLICY=$(cat $TEMP_POLICY_FILE | sed -e 's/[{}]/''/g' | awk -v k="text" '{n=split($0,a,","); for (i=1; i<=n; i++) print a[i]}'|awk '/Principal/ && !skip { print } { skip = /Deny/} '|grep ^\"Principal|grep \*)
#   if [[ $CHECK_BUCKET_ALLUSERS_ACL || $CHECK_BUCKET_AUTHUSERS_ACL || $CHECK_BUCKET_ALLUSERS_POLICY ]];then
#     if [[ $CHECK_BUCKET_ALLUSERS_ACL ]];then
#       textWarn "$BUCKET_LOCATION: $bucket bucket is open to the Internet (Everyone) with permissions: $CHECK_BUCKET_ALLUSERS_ACL_SINGLE_LINE" "$regx"
#     fi
#     if [[ $CHECK_BUCKET_AUTHUSERS_ACL ]];then
#       textWarn "$BUCKET_LOCATION: $bucket bucket is open to Authenticated users (Any AWS user) with permissions: $CHECK_BUCKET_AUTHUSERS_ACL_SINGLE_LINE" "$regx"
#     fi
#     if [[ $CHECK_BUCKET_ALLUSERS_POLICY ]];then
#       textWarn "$BUCKET_LOCATION: $bucket bucket policy \"may\" allow Anonymous users to perform actions (Principal: \"*\")" "$regx"
#     fi
#   else
#     textOK "$BUCKET_LOCATION: $bucket bucket is not open" "$regx"
#   fi
#   rm -fr $TEMP_POLICY_FILE
# }