Firewall.sol

The Firewall contract is the main contract of the system. It stores and manages all the Policies to which Firewall Consumers subscribe to, and executes them as needed.

Properties

Name	Type	Description
approvedPolicies	mapping (address => bool)	the Policies that can be used by Firewall Consumers that use this Firewall
subscribedPolicies	mapping (address => mapping (bytes4 => address[]) )	a mapping between the Protected Methods of a Firewall Consumer and the Policies configured for these methods
subscribedGlobalPolicies	mapping (address => address[])	a mapping between a Firewall Consumer and the Policies that are configured on it

Modifiers

onlyConsumerAdmin()

Only allows the modified function to run if it was called by the Firewall Admin (see setFirewallAdmin()) .

Methods

preExecution()

function preExecution(address sender, bytes calldata data, uint value)

Runs the Pre Execution hook on all the Policies that msg.sender has subscribed to for the method described by the first 4 bytes of data.

Parameter Name	Type	Description
sender	address	the sender of the transaction
data	bytes calldata	the transaction data
value	uint	the value that was sent with the transaction

postExecution()

function postExecution(address sender, bytes calldata data, uint value)

Runs the Post Execution hook on all the Policies that msg.sender has subscribed to for the method described by the first 4 bytes of data.

Parameter Name	Type	Description
sender	address	the sender of the transaction
data	bytes calldata	the transaction data
value	uint	the value that was sent with the transaction

setPolicyStatus()

function setPolicyStatus(address policy, bool status)

Callable only by the Firewall Owner, used to approve or revoke approval of a Policy. Revoking approval doesn’t remove existing consumer subscriptions.

Parameter Name	Type	Description
policy	address	the address of the policy to set the status for
status	bool	the new status of the policy, true meaning approved and false meaning unapproved see Approved Policies for more details

addPolicy()

function addPolicy(address consumer, bytes4 methodSig, address policy)

Callable only by the Firewall Admin of the Firewall Consumer, this method adds the Policy to the list of subscribed policies for the given method signature.

Parameter Name	Type	Description
consumer	address	the Firewall Consumer for which to add the Policy for
methodSig	bytes4	the method-sig for which to apply this Policy for
policy	address	the Policy to add

removePolicy()

function removePolicy(address consumer, bytes4 methodSig, uint policyIndex)

Callable only by the Firewall Admin of the consumer, this method removes the Policy found at the policyIndex from the list of subscribed policies for the given method signature.

Parameter Name	Type	Description
consumer	address	the Firewall Consumer for which to remove the Policy from
methodSig	bytes4	the method-sig for which to apply this Policy for
policyIndex	uint	the index of the Policy to remove

addPolicies()

function addPolicies(address consumer, bytes4[] calldata methodSigs, address[] calldata policies)

Callable only by the Firewall Admin of the Firewall Consumer, this method adds multiple policies to the list of subscribed policies for the given method signatures. Each Policy will be subscribed to the corresponding Method-Sig from the methodSigs array.

Parameter Name	Type	Description
consumer	address	the Firewall Consumer for which to add the Policy
methodSigs	bytes4[] calldata	the method-sig for which to apply this Policy for
policies	address[] calldata	the Policy to add

removePolicies()

function removePolicies(address consumer, bytes4[] calldata methodSigs, address[] calldata policies)

Callable only by the Firewall Admin of the Firewall Consumer, this method removes multiple policies from the list of subscribed policies for the given method signatures. Each Policy will be removed from the corresponding Method-Sig from the methodSigs array.

Parameter Name	Type	Description
consumer	address	the Firewall Consumer for which to remove the Policy from
methodSig	bytes4 calldata	the method-sig for which to apply this Policy for
policyIndex	uint calldata	the index of the Policy to remove

addGlobalPolicy()

function addGlobalPolicy(address consumer, address policy)

Callable only by the Firewall Admin of the Firewall Consumer, this method adds a Global Policy to the list of subscribed policies for the Firewall Consumer.

Parameter Name	Type	Description
consumer	address	the Firewall Consumer for which to add the policy for
policy	address	the Policy to add

removeGlobalPolicy()

function removeGlobalPolicy(address consumer, uint policyIndex)

Callable only by the Firewall Admin of the Firewall Consumer, this method removes a Global Policy from the list of subscribed policies for the Firewall Consumer.

Parameter Name	Type	Description
consumer	address	the Firewall Consumer for which to remove the Policy from
policyIndex	uint	the index of the Policy to remove

addGlobalPoliciesForConsumers()

function addGlobalPoliciesForConsumers(address[] consumers, address policy)

Callable only by the Firewall Admin of all the Firewall Consumers, this method adds a Global Policy to the list of subscribed policies for the all the Firewall Consumers.

Parameter Name	Type	Description
consumers	address[]	an array of Firewall Consumers to add the Policy to
policy	address	the address of the Policy to add

removeGlobalPoliciesForConsumers()

function removeGlobalPoliciesForConsumers(address[] consumers, address policy)

Callable only by the Firewall Admin of all the Firewall Consumers, this method removes a Global Policy from a list of Firewall Consumers.

Parameter Name	Type	Description
consumers	address[]	an array of Firewall Consumers to remove the Policy from
policy	address	the address of the Policy to remove

View Functions

getActivePolicies()

function getActivePolicies(address consumer, bytes4 methodSig) public returns (address[] memory)

Returns an array of all the policies a Firewall Consumer has subscribed to a method.

Parameter Name	Type	Description
consumer	address	the Firewall Consumer for which to get the active policies
methodSig	bytes4	the method signature we’re getting the active policies for

getActiveGloablPolicies()

function getActiveGloablPolicies(address consumer) public returns (address[] memory)

Returns an array of all the Global Policies a Firewall Consumer is subscribed to.

Parameter Name	Type	Description
consumer	address	the Firewall Consumer for which to get the active policies

Source Code

On our GitHub repository: Firewall.sol