Onchain permissioning uses smart contracts to store and administer the node, account, and admin allowlists. Using onchain permissioning enables all nodes to read the allowlists from a single source, the blockchain.
When using Onchain Account Permissioning, a node checks permissions when importing blocks. Meaning, a node only imports blocks in which all transactions are from authorized senders. If you disable Onchain Account Permissioning and your node accepts blocks without enforcing this rule, your node cannot resync with other nodes that are enforcing Onchain Account Permissioning rules (your node goes into forked state).
The permissioning smart contracts and permissioning management dapp are a separate product to Hyperledger Besu, located in the ConsenSys/permissioning-smart-contracts repository.
Custom smart contracts and dapps can be implemented to work with onchain permissioning.
The permissioning smart contracts provided in the ConsenSys/permissioning-smart-contracts repository are:
- Ingress contracts for nodes and accounts - proxy contracts defined in the genesis file to defer the permissioning logic to the Node Rules and Account Rules contracts. The Ingress contracts deploy to static addresses.
- Node Rules - stores the node allowlist and node allowlist operations (for example, add and remove).
- Account Rules - stores the accounts allowlist and account allowlist operations (for example, add and remove).
- Admin - stores the list of admin accounts and admin list operations (for example, add and remove). Admin accounts are stored in a single list for both nodes and accounts.
The permissioning contract has multiple interfaces, and each interface maps to a specific version of the Enterprise Ethereum Alliance Client Specification. Ensure that you specify the permissioning contract interface being used when starting Besu.
Permissioning management dapp
The permissioning management dapp provides view and maintain access to the allowlists.
Before v1.2, the management interface used Truffle, now deprecated. For an improved user experience, use the dapp.
Permissioning implements three allowlists:
- Accounts, which can submit transactions to the network.
- Nodes, which can join the network.
- Admins, which are accounts able to update the accounts and nodes allowlists.
Using account permissioning and privacy
If using account permissioning and privacy, a signing key must be specified using the
command line option and the corresponding public key
included in the accounts allowlist.
If nodes are not connecting as expected, set the log level to
and search for messages containing
Node permissioning to identify the issue.
--p2p-host command line option has been
correctly configured for all nodes with the
externally accessible address.
When a node joins the network, the node connects to the bootnodes until it synchronizes to the chain head, regardless of node permissions. After synchronization, the Account Rules and Node Rules smart contracts apply the permissioning rules.
If a synchronized node loses all peer connections (that is, it has zero peers), it reconnects to the bootnodes to rediscover peers.
All bootnodes must be on the nodes allowlist.