AWS S3 Bucket Name DNS Compliance

AnalysisType: policy
Filename: aws_s3_bucket_name_dns_compliance.py
PolicyID: "AWS.S3.Bucket.NameDNSCompliance"
DisplayName: "AWS S3 Bucket Name DNS Compliance"
Enabled: true
ResourceTypes:
  - AWS.S3.Bucket
Tags:
  - AWS
Severity: Info
Description: >
  This policy validates that the AWS S3 bucket name is DNS compliant.
Runbook: >
  https://docs.runpanther.io/alert-runbooks/built-in-policies/aws-s3-bucket-name-has-no-periods
Reference: https://docs.aws.amazon.com/AmazonS3/latest/dev/BucketRestrictions.html
Tests:
  - Name: Bucket Name Has No Periods
    ExpectedResult: true
    Resource:
      {
        "CreationDate": "2019-01-01T00:00:00Z",
        "EncryptionRules":
          [
            {
              "ApplyServerSideEncryptionByDefault":
                { "KMSMasterKeyID": null, "SSEAlgorithm": "AES256" },
            },
          ],
        "Grants":
          [
            {
              "Grantee":
                {
                  "DisplayName": "user.name",
                  "EmailAddress": null,
                  "ID": "11112223334445556667778899aaabbbcccdddeeee",
                  "Type": "CanonicalUser",
                  "URI": null,
                },
              "Permission": "FULL_CONTROL",
            },
            {
              "Grantee":
                {
                  "DisplayName": null,
                  "EmailAddress": null,
                  "ID": null,
                  "Type": "Group",
                  "URI": "http://acs.amazonaws.com/groups/s3/LogDelivery",
                },
              "Permission": "WRITE",
            },
          ],
        "LifecycleRules": null,
        "Location": "us-east-2",
        "LoggingPolicy": null,
        "MFADelete": null,
        "Name": "bucket-name",
        "Owner":
          {
            "DisplayName": "user.name",
            "ID": "11112223334445556667778899aaabbbcccdddeeee",
          },
        "Policy": null,
        "PublicAccessBlockConfiguration":
          {
            "BlockPublicAcls": false,
            "BlockPublicPolicy": false,
            "IgnorePublicAcls": false,
            "RestrictPublicBuckets": false,
          },
        "Versioning": null,
      }
  - Name: Bucket Name Has Periods
    ExpectedResult: false
    Resource:
      {
        "CreationDate": "2019-01-01T00:00:00Z",
        "EncryptionRules":
          [
            {
              "ApplyServerSideEncryptionByDefault":
                { "KMSMasterKeyID": null, "SSEAlgorithm": "AES256" },
            },
          ],
        "Grants":
          [
            {
              "Grantee":
                {
                  "DisplayName": "user.name",
                  "EmailAddress": null,
                  "ID": "11112223334445556667778899aaabbbcccdddeeee",
                  "Type": "CanonicalUser",
                  "URI": null,
                },
              "Permission": "FULL_CONTROL",
            },
            {
              "Grantee":
                {
                  "DisplayName": null,
                  "EmailAddress": null,
                  "ID": null,
                  "Type": "Group",
                  "URI": "http://acs.amazonaws.com/groups/s3/LogDelivery",
                },
              "Permission": "WRITE",
            },
          ],
        "LifecycleRules": null,
        "Location": "us-east-2",
        "LoggingPolicy": null,
        "MFADelete": null,
        "Name": "bucket.name",
        "Owner":
          {
            "DisplayName": "user.name",
            "ID": "11112223334445556667778899aaabbbcccdddeeee",
          },
        "Policy": null,
        "PublicAccessBlockConfiguration":
          {
            "BlockPublicAcls": false,
            "BlockPublicPolicy": false,
            "IgnorePublicAcls": false,
            "RestrictPublicBuckets": false,
          },
        "Versioning": null,
      }


# ------ paired body: aws_s3_bucket_name_dns_compliance.py ------

def policy(resource):
    return "." not in resource["Name"]