cdk-serverless-clamscan

cdk-serverless-clamscan

An aws-cdk construct that uses ClamAV® to scan newly uploaded objects to Amazon S3 for viruses. The construct provides a flexible interface for a system to act based on the results of a ClamAV virus scan. Check out this blogpost for a guided walkthrough.

Pre-Requisites

Docker: The ClamAV Lambda functions utilizes a container image that is built locally using docker bundling

Examples

This project uses projen and thus all the constructs follow language specific standards and naming patterns. For more information on how to translate the following examples into your desired language read the CDK guide on Translating TypeScript AWS CDK code to other languages

Example 1. (Default destinations with rule target)

typescript

import { RuleTargetInput } from 'aws-cdk-lib/aws-events';
import { SnsTopic } from 'aws-cdk-lib/aws-events-targets';
import { Bucket } from 'aws-cdk-lib/aws-s3';
import { Topic } from 'aws-cdk-lib/aws-sns';
import { Stack, StackProps } from 'aws-cdk-lib';
import { Construct } from 'constructs';
import { ServerlessClamscan } from 'cdk-serverless-clamscan';

export class CdkTestStack extends Stack {
  constructor(scope: Construct, id: string, props?: StackProps) {
    super(scope, id, props);

    const bucket_1 = new Bucket(this, 'rBucket1');
    const bucket_2 = new Bucket(this, 'rBucket2');
    const bucketList = [bucket_1, bucket_2];
    const sc = new ServerlessClamscan(this, 'rClamscan', {
      buckets: bucketList,
    });
    const bucket_3 = new Bucket(this, 'rBucket3');
    sc.addSourceBucket(bucket_3);
    const infectedTopic = new Topic(this, 'rInfectedTopic');
    sc.infectedRule?.addTarget(
      new SnsTopic(infectedTopic, {
        message: RuleTargetInput.fromEventPath(
          '$.detail.responsePayload.message',
        ),
      }),
    );
  }
}

python

from aws_cdk import (
  Stack,
  aws_events as events,
  aws_events_targets as events_targets,
  aws_s3 as s3,
  aws_sns as sns
)
from cdk_serverless_clamscan import ServerlessClamscan
from constructs import Construct

class CdkTestStack(Stack):

  def __init__(self, scope: Construct, construct_id: str, **kwargs) -> None:
    super().__init__(scope, construct_id, **kwargs)

    bucket_1 = s3.Bucket(self, "rBucket1")
    bucket_2 = s3.Bucket(self, "rBucket2")
    bucketList = [ bucket_1, bucket_2 ]
    sc = ServerlessClamscan(self, "rClamScan",
      buckets=bucketList,
    )
    bucket_3 = s3.Bucket(self, "rBucket3")
    sc.add_source_bucket(bucket_3)
    infected_topic = sns.Topic(self, "rInfectedTopic")
    if sc.infected_rule != None:
      sc.infected_rule.add_target(
        events_targets.SnsTopic(
          infected_topic,
          message=events.RuleTargetInput.from_event_path('$.detail.responsePayload.message'),
        )
      )

Example 2. (Bring your own destinations)

typescript

import {
  SqsDestination,
  EventBridgeDestination,
} from 'aws-cdk-lib/aws-lambda-destinations';
import { Bucket } from 'aws-cdk-lib/aws-s3';
import { Queue } from 'aws-cdk-lib/aws-sqs';
import { Stack, StackProps } from 'aws-cdk-lib';
import { Construct } from 'constructs';
import { ServerlessClamscan } from 'cdk-serverless-clamscan';

export class CdkTestStack extends Stack {
  constructor(scope: Construct, id: string, props?: StackProps) {
    super(scope, id, props);

    const bucket_1 = new Bucket(this, 'rBucket1');
    const bucket_2 = new Bucket(this, 'rBucket2');
    const bucketList = [bucket_1, bucket_2];
    const queue = new Queue(this, 'rQueue');
    const sc = new ServerlessClamscan(this, 'default', {
      buckets: bucketList,
      onResult: new EventBridgeDestination(),
      onError: new SqsDestination(queue),
    });
    const bucket_3 = new Bucket(this, 'rBucket3');
    sc.addSourceBucket(bucket_3);
  }
}

python

from aws_cdk import (
  Stack,
  aws_lambda_destinations as lambda_destinations,
  aws_s3 as s3,
  aws_sqs as sqs
)
from cdk_serverless_clamscan import ServerlessClamscan
from constructs import Construct

class CdkTestStack(Stack):

  def __init__(self, scope: Construct, construct_id: str, **kwargs) -> None:
    super().__init__(scope, construct_id, **kwargs)

    bucket_1 = s3.Bucket(self, "rBucket1")
    bucket_2 = s3.Bucket(self, "rBucket2")
    bucketList = [ bucket_1, bucket_2 ]
    queue = sqs.Queue(self, "rQueue")
    sc = ServerlessClamscan(self, "rClamScan",
      buckets=bucketList,
      on_result=lambda_destinations.EventBridgeDestination(),
      on_error=lambda_destinations.SqsDestination(queue),
    )
    bucket_3 = s3.Bucket(self, "rBucket3")
    sc.add_source_bucket(bucket_3)

Operation and Maintenance

When ClamAV publishes updates to the scanner you will see “Your ClamAV installation is OUTDATED” in your scan results. While the construct creates a system to keep the database definitions up to date, you must update the scanner to detect all the latest Viruses.

Update the docker images of the Lambda functions with the latest version of ClamAV by re-running cdk deploy.

Optionally Skip Files

In certain situations, you may have files which are already scanned and you wish to omit them from ClamAV scanning. In that case, simply tag the s3 object with "scan-status": "N/A" and the file will be automatically skipped.

Example 1. (Upload file to skip)

python/boto

boto3.client('s3').upload_file(
    Filename=file_path,
    Bucket=bucket_name,
    Key=object_key,
    ExtraArgs={'Tagging': 'scan-status=N/A'}
)

typscript/aws-sdk

const params = {
  Bucket: bucketName,
  Key: objectKey,
  Body: fileContent,
  Tagging: 'scan-status=N/A',
};
const command = new PutObjectCommand(params);
const response = await (new S3Client()).send(command);

API Reference

See API.md.

Contributing

See CONTRIBUTING for more information.

License

This project is licensed under the Apache-2.0 License.