IAM: Identity Access & Management

• IAM: Identity Access \& Management
  • What Is IAM?
    • IAM: Users \& Groups
    • IAM: Permissions
    • IAM Policies Structure
    • IAM - Password Policy
    • IAM Roles for Services
    • IAM Security Tools
    • IAM Guidelines \& Best Practices
    • Shared Responsibility Model for IAM
  • Multi Factor Authentication - MFA
  • MFA devices options in AWS
  • How can users access AWS ?
  • What’s the AWS CLI?
  • What’s the AWS SDK?
  • IAM Section - Summary

What Is IAM?

AWS Identity and Access Management (IAM) is a web service that helps you securely control access to AWS resources. You use IAM to control who is authenticated (signed in) and authorized (has permissions) to use resources.

IAM: Users & Groups

• IAM = Identity and Access Management, Global service
• Root account created by default, shouldn’t be used or shared
• Users are people within your organization, and can be grouped
• Groups only contain users, not other groups
• Users don’t have to belong to a group, and user can belong to multiple groups

IAM: Permissions

• Users or Groups can be assigned JSON documents called policies
• These policies define the permissions of the users
• In AWS you apply the least privilege principle: don’t give more permissions than a user needs

IAM Policies Structure

• Consists of
  • Version: policy language version, always include “2012-10-17”
  • Id: an identifier for the policy (optional)
  • Statement: one or more individual statements (required)
• Statements consists of
  • Sid: an identifier for the statement (optional)
  • Effect: whether the statement allows or denies access (Allow, Deny)
  • Principal: account/user/role to which this policy applied to
  • Action: list of actions this policy allows or denies
  • Resource: list of resources to which the actions applied to
  • Condition: conditions for when this policy is in effect (optional)

Example:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": "ec2:Describe*",
      "Resource": "*"
    },
    {
      "Effect": "Allow",
      "Action": "elasticloadbalancing:Describe*",
      "Resource": "*"
    },
    {
      "Effect": "Allow",
      "Action": [
        "cloudwatch:ListMetrics",
        "cloudwatch:GetMetricStatistics",
        "cloudwatch:Describe*"
      ],
      "Resource": "*"
    }
  ]
}

IAM - Password Policy

• Strong passwords = higher security for your account
• In AWS, you can setup a password policy:
  • Set a minimum password length
  • Require specific character types:
    • including uppercase letters
    • lowercase letters
    • numbers
    • non-alphanumeric characters
• Allow all IAM users to change their own passwords
• Require users to change their password after some time (password expiration)
• Prevent password re-use

IAM Roles for Services

• Some AWS service will need to perform actions on your behalf
• To do so, we will assign permissions to AWS services with IAM Roles
• Common roles:
  • EC2 Instance Roles
  • Lambda Function Roles
  • Roles for CloudFormation

IAM Security Tools

• IAM Credentials Report (account-level)
  • a report that lists all your account’s users and the status of their various credentials
• IAM Access Advisor (user-level)
  • Access advisor shows the service permissions granted to a user and when those services were last accessed.
  • You can use this information to revise your policies.

IAM Guidelines & Best Practices

• Don’t use the root account except for AWS account setup
• One physical user = One AWS user
• Assign users to groups and assign permissions to groups
• Create a strong password policy
• Use and enforce the use of Multi Factor Authentication (MFA)
• Create and use Roles for giving permissions to AWS services
• Use Access Keys for Programmatic Access (CLI / SDK)
• Audit permissions of your account with the IAM Credentials Report
• Never share IAM users & Access Keys

Shared Responsibility Model for IAM

AWS	YOU
Infrastructure (global network security)	Users, Groups, Roles, Policies management and monitoring
Configuration and vulnerability analysis	Enable MFA on all accounts
Compliance validation	Rotate all your keys often, Use IAM tools to apply appropriate permissions, Analyze access patterns & review permissions

Multi Factor Authentication - MFA

• Users have access to your account and can possibly change configurations or delete resources in your AWS account
• You want to protect your Root Accounts and IAM users
• MFA = password you know + security device you own
• Main benefit of MFA: if a password is stolen or hacked, the account is not compromised

MFA devices options in AWS

• Virtual MFA device (Support for multiple tokens on a single device.)
  • Google Authenticator (phone only)
  • Authy (multi-device)
• Universal 2nd Factor (U2F) Security Key (Support for multiple root and IAM users using a single security key)
  • YubiKey by Yubico (3rd party)
• Hardware Key Fob MFA Device
• Hardware Key Fob MFA Device for AWS GovCloud (US)

How can users access AWS ?

• To access AWS, you have three options:
  • AWS Management Console (protected by password + MFA)
  • AWS Command Line Interface (CLI): protected by access keys
  • AWS Software Developer Kit (SDK) - for code: protected by access keys
• Access Keys are generated through the AWS Console
• Users manage their own access keys
• Access Keys are secret, just like a password. Don’t share them
• Access Key ID ~= username
• Secret Access Key ~= password

What’s the AWS CLI?

• A tool that enables you to interact with AWS services using commands in your command-line shell
• Direct access to the public APIs of AWS services
• You can develop scripts to manage your resources
• It’s open-source https://github.com/aws/aws-cli
• Alternative to using AWS Management Console

What’s the AWS SDK?

• AWS Software Development Kit (AWS SDK)
• Language-specific APIs (set of libraries)
• Enables you to access and manage AWS services programmatically
• Embedded within your application
• Supports
  • SDKs (JavaScript, Python, PHP, .NET, Ruby, Java, Go, Node.js, C++)
  • Mobile SDKs (Android, iOS, …)
  • IoT Device SDKs (Embedded C, Arduino, …)
• Example: AWS CLI is built on AWS SDK for Python

IAM Section - Summary

• Users: mapped to a physical user, has a password for AWS Console
• Groups: contains users only
• Policies: JSON document that outlines permissions for users or groups
• Roles: for EC2 instances or AWS services
• Security: MFA + Password Policy
• AWS CLI: manage your AWS services using the command-line
• AWS SDK: manage your AWS services using a programming language
• Access Keys: access AWS using the CLI or SDK
• Audit: IAM Credential Reports & IAM Access Advisor