Crate zebra_consensus

Implementation of Zcash consensus checks.

More specifically, this crate implements semantic validity checks, as defined below.

Verification levels.

Zebra’s implementation of the Zcash consensus rules is oriented around three telescoping notions of validity:

1. Structural Validity, or whether the format and structure of the object are valid. For instance, Sprout-on-BCTV14 proofs are not allowed in version 4 transactions, and a transaction with a spend or output description must include a binding signature.

2. Semantic Validity, or whether the object could potentially be valid, depending on the chain state. For instance, a transaction that spends a UTXO must supply a valid unlock script; a shielded transaction must have valid proofs, etc.

3. Contextual Validity, or whether a semantically valid transaction is actually valid in the context of a particular chain state. For instance, a transaction that spends a UTXO is only valid if the UTXO remains unspent; a shielded transaction spending some note must reveal a nullifier not already in the nullifier set, etc.

Structural validity is enforced by the definitions of data structures in zebra-chain. Semantic validity is enforced by the code in this crate. Contextual validity is enforced in zebra-state when objects are committed to the chain state.

Re-exports

• pub use config::Config;
• pub use error::BlockError;
• pub use router::RouterError;

Modules

• block 🔒
  Consensus-based block verification.
• checkpoint 🔒
  Checkpoint-based block verification.
• config
  Configuration for semantic verification which is run in parallel.
• ed25519
  Async Ed25519 batch verifier service
• error
  Errors that can occur when checking consensus rules.
• groth16
  Async Groth16 batch verifier service
• halo2
  Async Halo2 batch verifier service
• primitives 🔒
  Asynchronous verification of cryptographic primitives.
• redjubjub
  Async RedJubjub batch verifier service
• redpallas
  Async RedPallas batch verifier service
• router
  Top-level semantic block verification for Zebra.
• script 🔒
• transaction
  Asynchronous verification of transactions.

Structs

• CheckpointList
  A list of block height and hash checkpoints.

Enums

• Request
  A request to the chain or block verifier
• VerifyBlockError
  Block verification errors.
• VerifyCheckpointError

Constants

• MAX_BLOCK_SIGOPS
  The maximum allowed number of legacy signature check operations in a block.
• MAX_CHECKPOINT_BYTE_COUNT
  We limit the memory usage and download contention for each checkpoint, based on the cumulative size of the serialized blocks in the chain.
• MAX_CHECKPOINT_HEIGHT_GAP
  We limit the maximum number of blocks in each checkpoint. Each block uses a constant amount of memory for the supporting data structures and futures.

Traits

• ParameterCheckpoint
  Network methods related to checkpoints

Functions

• block_subsidy
  BlockSubsidy(height) as described in protocol specification §7.8
• difficulty_is_valid
  Returns Ok(()) if hash passes:
• funding_stream_address
  Return the address corresponding to given height, network and funding stream receiver.
• funding_stream_values
  Returns the fs.Value(height) for each stream receiver as described in protocol specification §7.8
• miner_subsidy
  MinerSubsidy(height) as described in protocol specification §7.8
• new_coinbase_script
  Returns a new funding stream coinbase output lock script, which pays to the P2SH address.

Type Aliases

• BoxError
  A boxed std::error::Error.