> For the complete documentation index, see [llms.txt](https://docs.ironblocks.com/firewall/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ironblocks.com/firewall/policies/eoa-only.md).

# EOA Only

## Overview

This policy will only allow an EOA to interact with your smart contracts, which is useful if you know that your protocol is expected to only server external users.

> If you're protocol has multiple smart contracts where each of them should only be allowed to access from an EOA - but can themselves interact with each other - this policy allows for this too.

## Protected Attack Vector

Most attacks on the smart contracts come from other, malicious smart contracts which are specially crafted to exploit some vulnerability in a protocol's business logic.

This policy protects against this attack vector by only allowing EOAs to interact with your smart contracts, so that a transaction coming from a malicious smart contract will be blocked.

## How It Works

1. When a transaction reaches this policy, it first checks if the sender is an EOA - or alternatively - if it's coming from a contract that was allowlisted *(i.e. a different smart contract in your protocol)*.<br>
2. If the above check passes, the transaction will be allowed to go through.<br>
3. Otherwise, the transaction will be reverted.

## Setup Instructions

1. Deploy your own version of this policy *(see* [*Source Code*](#source-code)*)*.<br>
2. Call the [setAllowedContracts()](#setallowedcontracts) method to configure any smart contracts within your protocol that should be allowed to interact with each other.<br>
3. Add the newly deployed policy to the [Firewall](/firewall/glossary.md#firewall) *(you can do this* [*Globally*](/firewall/configuration/firewall-configuration.md#global-policies) *or* [*Per-Method*](/firewall/configuration/firewall-configuration.md#per-method-policies)*, see* [*Policy Administration*](/firewall/configuration/policy-administration.md)*)*.<br>
4. That's it!

## Properties

<table><thead><tr><th width="220">Name</th><th width="256.3333333333333">Type</th><th>Description</th></tr></thead><tbody><tr><td><code>allowedContracts</code></td><td><p><code>mapping</code></p><p><code>(address => bool)</code></p></td><td>the allowlist of contracts that are allowed to interact with your smart contracts<br><br>these would normally be other smart contracts in your protocol which should be allowed to interact with each other</td></tr></tbody></table>

## Methods

### setAllowedContracts()

#### `function setAllowedContracts(address contractAddress, bool status)`

Callable only by the policy owner. Sets whether or `contractAddress` is allowlisted in this policy.<br>

| Parameter Name    | Type      | Description                                                |
| ----------------- | --------- | ---------------------------------------------------------- |
| `contractAddress` | `address` | the address of a smart contract to be allowed / disallowed |
| `status`          | `bool`    | the status of the approval                                 |

<br>

## **Security Lifecycle**

This policy runs during the [Firewall's Pre-Execution hook](/firewall/glossary.md#pre-execution).

## Source Code

On our GitHub repository: [OnlyEOAPolicy.sol](https://github.com/ironblocks/onchain-firewall/blob/main/packages/onchain-firewall/contracts/policies/OnlyEOAPolicy.sol)