Xuper

Smart Contract

1. Support transfer to contract and transfer from a contract.
2. Contract SDK add builtin Account type for user accounts.
3. Add contract template for digital assets.

Performance Improvements

1. Support block/transaction compression in P2P message.
2. Add contract data cache to speed up the contract execution.

Other Improvements

1. Support update gas price by proposal/vote system.
2. Add interface to query the available and frozen UTXO of user account.
3. Plugin system support autoload plugins from given folder.
4. Several bug fixes.

New Features

* **Performance Improvement**
* Verify transactions parallel in a block using DAG.

* **Consensus**
* Add new Chained-BFT module into consensus;
* Integrate DPoS with Chained-BFT, note that this feature is still in preview.

* **Smart Contract**
* Contract SDK supports print log into log file;
* Contract supports get block/transaction data;
* Define the standard error code of contracts' return message;
* Add new contract build and test tool.

* **Security Enhancements**
* Support multisig and ring signature in crypto module;
* Disable external invoke of initialize function of WASM contracts;
* Refine the verification process of transaction, avoid the risk of some auth_require addresses were used without verification in contract context.

* **Other Features**
* Limit initiator to address only to simplify permission check;
* Improve the UTXO walk process, support truncating ledger in some forked cases;
* Support update the config of reserve contracts, and some more improvements on reserve contracts.

New Features

* **Performance Improvement**
* Add new KV engine badger;
* Improve log context init performance;
* Add new crypto plugin using schnorr signature;

* **Smart Contract**
* Resource cost support Memory and Disk usage;
* Context support getting transaction's initiator and auth_require info;
* VM could stop immediately when running out of resource;

* **Security Enhancements**
* Add P2P address identity protocol to binding peer's netURL with node address;
* Routing Security: support core peers connecting to each other directly to keep core network safe.
* Security Patchs: Limit the connection number from the same IP; Validate autogen tx to avoid fake transaction attack; Fix UTXO with negative frozen heigh could pass transaction check; Check the number of coinbase transactions in a block to avoid byzantine miner;

* **Other Features**
* CLI support getting DPoS status, querying all contracts belongs to a contract account and all contract accounts contains specified address in account ACL.
* Compliance Features: Unified reserve contracts validation framework; Add several reserve contracts such as endorse-based transfer; Support forbidding contracts by contracts' name;
* Add new API **PreExecWithSelectUTXO** which pre-execute contract request and return enough UTXO records with the contract result.

This is the first public release of XuperUnion which introduces a highly flexible blockchain architecture with great transaction performance.