Federating AWS Access with Active Directory (AD FS) for Hybrid Cloud Access

SecureCart operates both on-premises infrastructure and AWS cloud. Employees, especially Software Architects, need to securely access both environments using their existing on-premises Active Directory (AD) credentials without managing separate AWS IAM users.

✅ Goals: ✔ Provide seamless authentication using Active Directory Federation Services (AD FS). ✔ Allow temporary access to AWS resources via IAM roles instead of IAM users. ✔ Enable secure and scalable hybrid cloud access for SecureCart employees.

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📌 Solution Architecture

SecureCart implements SAML 2.0 Federation with AD FS, allowing employees to log in with their existing AD credentials and assume IAM roles in AWS.

🔹 Components Involved: ✔ Active Directory (AD) → Manages SecureCart user identities. ✔ Active Directory Federation Services (AD FS) → Acts as the identity provider (IdP), issuing SAML assertions. ✔ AWS IAM Roles → Define permissions for accessing AWS resources. ✔ AWS Security Token Service (STS) → Issues temporary credentials based on SAML authentication.

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📌 Step-by-Step Setup Guide

1️⃣ Set Up Active Directory Federation Services (AD FS)

🔹 SecureCart’s IT team sets up AD FS on-premises to manage authentication. 🔹 AD FS validates users via Active Directory and issues SAML assertions.

✔ Action Items: 1️⃣ Install and configure AD FS on a Windows Server. 2️⃣ Set up relying party trust for AWS in AD FS. 3️⃣ Configure SAML claim rules to send user attributes (e.g., username, department, role).

🔹 Why This Matters? ✅ Employees log in using their corporate credentials—no separate AWS credentials required. ✅ AD FS verifies identity and passes authentication info to AWS via SAML assertion.

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2️⃣ Configure AWS as a SAML Service Provider

🔹 SecureCart registers AD FS as an Identity Provider (IdP) in AWS IAM.

✔ Action Items: 1️⃣ In AWS IAM, create a new identity provider. 2️⃣ Upload the SAML metadata file from AD FS. 3️⃣ Configure IAM roles for federated users (Software Architects, Developers, etc.).

🔹 Why This Matters? ✅ Allows AWS to trust authentication requests from SecureCart’s AD FS. ✅ IAM roles map federated user attributes to specific AWS permissions.

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3️⃣ Create IAM Roles for SecureCart Employees

📌 IAM roles define which AWS resources employees can access based on their AD group membership.

✔ Action Items: 1️⃣ Create an IAM Role for Software Architects (SecureCart-Architects). 2️⃣ Define trust relationships to allow assumption via SAML federation. 3️⃣ Attach permissions to the role (e.g., access to EC2, RDS, S3, VPC).

🔹 Example IAM Role Trust Policy

jsonCopyEdit{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Federated": "arn:aws:iam::123456789012:saml-provider/SecureCart-ADFS"
      },
      "Action": "sts:AssumeRoleWithSAML",
      "Condition": {
        "StringEquals": {
          "SAML:aud": "https://signin.aws.amazon.com/saml"
        }
      }
    }
  ]
}

🔹 Why This Matters? ✅ IAM roles dynamically map permissions based on user attributes. ✅ Employees assume roles via STS instead of needing IAM users.

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4️⃣ SecureCart Employees Log In & Assume IAM Roles

📌 After setup, SecureCart employees use their Active Directory credentials to access AWS.

✔ Action Items: 1️⃣ Employees log in to the SecureCart AD FS portal. 2️⃣ AD FS authenticates users and redirects them to AWS via SAML assertion. 3️⃣ AWS grants temporary IAM session tokens based on assigned IAM roles.

🔹 Why This Matters? ✅ No persistent AWS credentials needed—all authentication is federated. ✅ Users only receive permissions assigned to their role.

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📌 SecureCart User Experience Flow

1️⃣ Authentication via SecureCart AD FS

👤 User Action: ✔ Employee logs into SecureCart's AD FS portal with their Active Directory credentials.

🔹 Behind the Scenes: ✅ AD FS authenticates user credentials against Active Directory. ✅ Generates a SAML assertion with user attributes.

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2️⃣ Role Assumption in AWS

👤 User Action: ✔ Employee is redirected to AWS, assuming an IAM role.

🔹 Behind the Scenes: ✅ AWS IAM validates the SAML assertion. ✅ IAM maps the employee to an IAM role based on their AD group. ✅ AWS STS issues temporary credentials valid for up to 12 hours.

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3️⃣ SecureCart Employees Access AWS Resources

👤 User Action: ✔ Employee accesses AWS Console, EC2, S3, RDS, or VPC resources as per their IAM role.

🔹 Behind the Scenes: ✅ IAM restricts access to only authorized AWS services. ✅ AWS CloudTrail logs all actions for compliance tracking.

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📌 SecureCart User Experience Flow Diagram

pgsqlCopyEdit+-----------------------------+
| SecureCart Employee         |
+-----------------------------+
           |
           | (1) Logs in to SecureCart AD FS  
           V
+-----------------------------+
| Active Directory (AD FS)    |
+-----------------------------+
           |
           | (2) AD FS authenticates & issues SAML assertion  
           V
+-----------------------------+
| AWS IAM Role Assumption     |
+-----------------------------+
           |
           | (3) AWS STS issues temporary IAM credentials  
           V
+-----------------------------+
| SecureCart AWS Resources    |
+-----------------------------+
           |
           | (4) Employee accesses AWS services  
           V
+-----------------------------+
| EC2 | RDS | S3 | VPC | etc. |
+-----------------------------+

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📌 Summary

🚀 SecureCart enables federated access using AD FS and SAML 2.0, allowing employees to log into AWS with their corporate credentials. ✅ IAM roles dynamically grant permissions based on AD groups. ✅ AWS STS ensures temporary credentialing—eliminating the need for IAM users. ✅ SecureCart employees can access AWS resources securely without additional login steps.