AWS - Lambda with AWS CloudTrail

We can enable CloudTrail in our AWS account to get logs of API calls and related events history in our account. CloudTrail records all of the API access events as objects in our Amazon S3 bucket that we specify at the time we enable CloudTrail.

Because CloudTrail provides a record of our AWS API calls we can use this data to gain visibility into user activity, troubleshoot operational and security incidents.

We can take advantage of Amazon S3's bucket notification feature and direct Amazon S3 to publish object-created events to AWS Lambda.

Whenever CloudTrail writes logs to our S3 bucket, Amazon S3 can then invoke our Lambda function by passing the Amazon S3 object-created event as a parameter. The S3 event provides information, including the bucket name and key name of the log object that CloudTrail created.

Our Lambda function code can read the log object and process the access records logged by CloudTrail.

For example, we might write Lambda function code to notify us if specific API call was made in our account. In our sample, we enable CloudTrail so it can write access logs to our S3 bucket we configured. As for Lambda, S3 is the event source, and it publishes events (such as object-created event) to AWS Lambda and invokes our Lambda function.

When S3 invokes our Lambda function, it passes an S3 event identifying, among other things, the bucket name and key name of the object that CloudTrail created. The Lambda function can read the log object, and it knows the API calls that were reported in the log.

Each object CloudTrail creates in our S3 bucket is a JSON object, with one or more event records. Each record, among other things, provides eventSource and eventName.

We need turne on AWS CloudTrail for our AWS account to maintain records (logs) of AWS API calls made on our account.

Note that only a reagion where it's created is turned on!

Pic credit : Using AWS Lambda with AWS CloudTrail

The step in the diagram can be summarized as follows:

1. AWS CloudTrail saves logs to an S3 bucket (object-created event).
2. Amazon S3 detects the object-created event.
3. Amazon S3 publishes the s3:ObjectCreated:* event to AWS Lambda by invoking the Lambda function, as specified in the bucket notification configuration. Because the Lambda function's access permissions policy includes permissions for Amazon S3 to invoke the function, Amazon S3 can invoke the function.
4. AWS Lambda executes the Lambda function by assuming the execution role that we specified at the time you created the Lambda function.
5. The Lambda function reads the Amazon S3 event it receives as a parameter, determines where the CloudTrail object is, reads the CloudTrail object, and then it processes the log records in the CloudTrail object.
6. If the log includes a record with specific eventType and eventSource values, it publishes the event to our Amazon SNS topic. In Tutorial: Using AWS Lambda with AWS CloudTrail, we subscribe to the SNS topic using the email protocol, so we get email notifications.



Policy attached to the role:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "AWSCloudTrailCreateLogStream20141101",
      "Effect": "Allow",
      "Action": [
        "logs:CreateLogStream"
      ],
      "Resource": [
        "arn:aws:logs:us-east-1:526262051452:log-group:CloudTrail/DefaultLogGroup:log-stream:526262051452_CloudTrail_us-east-1*"
      ]
    },
    {
      "Sid": "AWSCloudTrailPutLogEvents20141101",
      "Effect": "Allow",
      "Action": [
        "logs:PutLogEvents"
      ],
      "Resource": [
        "arn:aws:logs:us-east-1:526262051452:log-group:CloudTrail/DefaultLogGroup:log-stream:526262051452_CloudTrail_us-east-1*"
      ]
    }
  ]
}



7. Each object CloudTrail creates in our S3 bucket is a JSON object, with one or more event records. Each record, among other things, provides eventSource and eventName.

{
  "Records":[
    ...
    {
      "eventVersion":"1.04",
      "userIdentity":{
        "type":"Root",
        "principalId":"526262051452",
        "arn":"arn:aws:iam::526262051452:root",
        "accountId":"526262051452",
        "accessKeyId":"....",
        "sessionContext":{
          "attributes":{
            "mfaAuthenticated":"false",
            "creationDate":"2017-06-05T04:06:42Z"
          }
	}
      },
      "eventTime":"2017-06-05T05:18:56Z",
      "eventSource":"sns.amazonaws.com",
      "eventName":"CreateTopic",
      "awsRegion":"us-east-1",
      "sourceIPAddress":"107.203.254.106",
      "userAgent":"AWSCloudTrail, aws-internal/3",
      "requestParameters":null,
      "responseElements":null,
      "requestID":"a1e71724-016c-58bf-8cb0-468aed6ce321",
      "eventID":"5a1e05f5-c5ca-424a-b837-959e25d6aea7",
      "eventType":"AwsApiCall","recipientAccountId":"526262051452"
      }
    },
    ...
}




The Lambda function notifies us by email if an API call to create an Amazon SNS topic is reported in the log. That is, when our Lambda function parses the log, it looks for records with the following:

"eventSource":"sns.amazonaws.com",
"eventName":"ListTopics",
eventName = "CreateTopic"

If found, it publishes the event to our Amazon SNS topic.

AWS (Amazon Web Services)

1. AWS : EKS (Elastic Container Service for Kubernetes)
2. AWS : Creating a snapshot (cloning an image)
3. AWS : Attaching Amazon EBS volume to an instance
4. AWS : Adding swap space to an attached volume via mkswap and swapon
5. AWS : Creating an EC2 instance and attaching Amazon EBS volume to the instance using Python boto module with User data
6. AWS : Creating an instance to a new region by copying an AMI
7. AWS : S3 (Simple Storage Service) 1
8. AWS : S3 (Simple Storage Service) 2 - Creating and Deleting a Bucket
9. AWS : S3 (Simple Storage Service) 3 - Bucket Versioning
10. AWS : S3 (Simple Storage Service) 4 - Uploading a large file
11. AWS : S3 (Simple Storage Service) 5 - Uploading folders/files recursively
12. AWS : S3 (Simple Storage Service) 6 - Bucket Policy for File/Folder View/Download
13. AWS : S3 (Simple Storage Service) 7 - How to Copy or Move Objects from one region to another
14. AWS : S3 (Simple Storage Service) 8 - Archiving S3 Data to Glacier
15. AWS : Creating a CloudFront distribution with an Amazon S3 origin
16. AWS : Creating VPC with CloudFormation
17. AWS : WAF (Web Application Firewall) with preconfigured CloudFormation template and Web ACL for CloudFront distribution
18. AWS : CloudWatch & Logs with Lambda Function / S3
19. AWS : Lambda Serverless Computing with EC2, CloudWatch Alarm, SNS
20. AWS : Lambda and SNS - cross account
21. AWS : CLI (Command Line Interface)
22. AWS : CLI (ECS with ALB & autoscaling)
23. AWS : ECS with cloudformation and json task definition
24. AWS Application Load Balancer (ALB) and ECS with Flask app
25. AWS : Load Balancing with HAProxy (High Availability Proxy)
26. AWS : VirtualBox on EC2
27. AWS : NTP setup on EC2
28. AWS: jq with AWS
29. AWS & OpenSSL : Creating / Installing a Server SSL Certificate
30. AWS : OpenVPN Access Server 2 Install
31. AWS : VPC (Virtual Private Cloud) 1 - netmask, subnets, default gateway, and CIDR
32. AWS : VPC (Virtual Private Cloud) 2 - VPC Wizard
33. AWS : VPC (Virtual Private Cloud) 3 - VPC Wizard with NAT
34. DevOps / Sys Admin Q & A (VI) - AWS VPC setup (public/private subnets with NAT)
35. AWS - OpenVPN Protocols : PPTP, L2TP/IPsec, and OpenVPN
36. AWS : Autoscaling group (ASG)
37. AWS : Setting up Autoscaling Alarms and Notifications via CLI and Cloudformation
38. AWS : Adding a SSH User Account on Linux Instance
39. AWS : Windows Servers - Remote Desktop Connections using RDP
40. AWS : Scheduled stopping and starting an instance - python & cron
41. AWS : Detecting stopped instance and sending an alert email using Mandrill smtp
42. AWS : Elastic Beanstalk with NodeJS
43. AWS : Elastic Beanstalk Inplace/Rolling Blue/Green Deploy
44. AWS : Identity and Access Management (IAM) Roles for Amazon EC2
45. AWS : Identity and Access Management (IAM) Policies, sts AssumeRole, and delegate access across AWS accounts
46. AWS : Identity and Access Management (IAM) sts assume role via aws cli2
47. AWS : Creating IAM Roles and associating them with EC2 Instances in CloudFormation
48. AWS Identity and Access Management (IAM) Roles, SSO(Single Sign On), SAML(Security Assertion Markup Language), IdP(identity provider), STS(Security Token Service), and ADFS(Active Directory Federation Services)
49. AWS : Amazon Route 53
50. AWS : Amazon Route 53 - DNS (Domain Name Server) setup
51. AWS : Amazon Route 53 - subdomain setup and virtual host on Nginx
52. AWS Amazon Route 53 : Private Hosted Zone
53. AWS : SNS (Simple Notification Service) example with ELB and CloudWatch
54. AWS : Lambda with AWS CloudTrail
55. AWS : SQS (Simple Queue Service) with NodeJS and AWS SDK
56. AWS : Redshift data warehouse
57. AWS : CloudFormation
58. AWS : CloudFormation Bootstrap UserData/Metadata
59. AWS : CloudFormation - Creating an ASG with rolling update
60. AWS : Cloudformation Cross-stack reference
61. AWS : OpsWorks
62. AWS : Network Load Balancer (NLB) with Autoscaling group (ASG)
63. AWS CodeDeploy : Deploy an Application from GitHub
64. AWS EC2 Container Service (ECS)
65. AWS EC2 Container Service (ECS) II
66. AWS Hello World Lambda Function
67. AWS Lambda Function Q & A
68. AWS Node.js Lambda Function & API Gateway
69. AWS API Gateway endpoint invoking Lambda function
70. AWS API Gateway invoking Lambda function with Terraform
71. AWS API Gateway invoking Lambda function with Terraform - Lambda Container
72. Amazon Kinesis Streams
73. AWS: Kinesis Data Firehose with Lambda and ElasticSearch
74. Amazon DynamoDB
75. Amazon DynamoDB with Lambda and CloudWatch
76. Loading DynamoDB stream to AWS Elasticsearch service with Lambda
77. Amazon ML (Machine Learning)
78. Simple Systems Manager (SSM)
79. AWS : RDS Connecting to a DB Instance Running the SQL Server Database Engine
80. AWS : RDS Importing and Exporting SQL Server Data
81. AWS : RDS PostgreSQL & pgAdmin III
82. AWS : RDS PostgreSQL 2 - Creating/Deleting a Table
83. AWS : MySQL Replication : Master-slave
84. AWS : MySQL backup & restore
85. AWS RDS : Cross-Region Read Replicas for MySQL and Snapshots for PostgreSQL
86. AWS : Restoring Postgres on EC2 instance from S3 backup
87. AWS : Q & A
88. AWS : Security
89. AWS : Security groups vs. network ACLs
90. AWS : Scaling-Up
91. AWS : Networking
92. AWS : Single Sign-on (SSO) with Okta
93. AWS : JIT (Just-in-Time) with Okta