Merge #4900

4900: Add block info support to EE and Casper VM (#4853) r=EdHastingsCasperAssociation a=EdHastingsCasperAssociation

This PR adds block info support to the ExecutionEngine and Casper VM. Wasm based logic can request the following fields via a new ffi method directly:

    /// This function gets the requested field at `field_idx`. It is up to
    /// the caller to ensure that the correct number of bytes for the field data
    /// are allocated at `dest_ptr`, otherwise data corruption in the wasm memory may occur.
    ///
    /// # Arguments
    ///
    /// * `field_idx` - what info field is requested?
    ///     0 => block time (functionally equivalent to earlier get_blocktime ffi)
    ///     1 => block height
    ///     2 => parent block hash
    ///     3 => state hash
    /// * `dest_ptr` => pointer in wasm memory where to write the result
    pub fn casper_get_block_info(field_idx: u8, dest_ptr: *const u8);

Alternately, the following convenience methods in the contract api offer easy access to each of the four fields, handling the ffi interactions for the user:
* get_blocktime() -> BlockTime (pre-existing)
* get_block_height() -> u64
* get_parent_block_hash() -> Digest
* get_state_hash() -> Digest

This new mechanism is extensible, and we may add more fields in future releases.

Co-authored-by: Ed Hastings <[email protected]>

execution_engine/src/engine_state/mod.rs

@@ -23,7 +23,7 @@ pub use engine_config::{
 };
 pub use error::Error;
 use execution_kind::ExecutionKind;
-pub use wasm_v1::{ExecutableItem, InvalidRequest, WasmV1Request, WasmV1Result};
+pub use wasm_v1::{BlockInfo, ExecutableItem, InvalidRequest, WasmV1Request, WasmV1Result};
 
 /// The maximum amount of motes that payment code execution can cost.
 pub const MAX_PAYMENT_AMOUNT: u64 = 2_500_000_000;
@@ -60,8 +60,7 @@ impl ExecutionEngineV1 {
  &self,
  state_provider: &impl StateProvider,
  WasmV1Request {
- state_hash,
- block_time,
+ block_info,
  transaction_hash,
  gas_limit,
  initiator_addr,
@@ -80,6 +79,7 @@ impl ExecutionEngineV1 {
 
  let account_hash = initiator_addr.account_hash();
  let protocol_version = self.config.protocol_version();
+ let state_hash = block_info.state_hash;
  let tc = match state_provider.tracking_copy(state_hash) {
  Ok(Some(tracking_copy)) => Rc::new(RefCell::new(tracking_copy)),
  Ok(None) => return WasmV1Result::root_not_found(gas_limit, state_hash),
@@ -133,7 +133,7 @@ impl ExecutionEngineV1 {
  access_rights,
  authorization_keys,
  account_hash,
- block_time,
+ block_info,
  transaction_hash,
  gas_limit,
  protocol_version,

execution_engine/src/engine_state/wasm_v1.rs

@@ -9,9 +9,9 @@ use thiserror::Error;
 use casper_storage::data_access_layer::TransferResult;
 use casper_types::{
  account::AccountHash, bytesrepr::Bytes, contract_messages::Messages, execution::Effects,
- BlockTime, DeployHash, Digest, ExecutableDeployItem, Gas, InitiatorAddr, Phase, PricingMode,
- RuntimeArgs, Transaction, TransactionCategory, TransactionEntryPoint, TransactionHash,
- TransactionInvocationTarget, TransactionTarget, TransactionV1, Transfer,
+ BlockHash, BlockTime, DeployHash, Digest, ExecutableDeployItem, Gas, InitiatorAddr, Phase,
+ PricingMode, RuntimeArgs, Transaction, TransactionCategory, TransactionEntryPoint,
+ TransactionHash, TransactionInvocationTarget, TransactionTarget, TransactionV1, Transfer,
 };
 
 use crate::engine_state::{DeployItem, Error as EngineError};
@@ -65,13 +65,66 @@ pub enum ExecutableItem {
  Invocation(TransactionInvocationTarget),
 }
 
-/// A request to execute the given Wasm on the V1 runtime.
-#[derive(Debug)]
-pub struct WasmV1Request {
+/// Block info.
+#[derive(Copy, Clone, Debug)]
+pub struct BlockInfo {
  /// State root hash of the global state in which the transaction will be executed.
  pub state_hash: Digest,
  /// Block time represented as a unix timestamp.
  pub block_time: BlockTime,
+ /// Parent block hash
+ pub parent_block_hash: BlockHash,
+ /// Block height
+ pub block_height: u64,
+}
+
+impl BlockInfo {
+ /// A new instance of `[BlockInfo]`.
+ pub fn new(
+ state_hash: Digest,
+ block_time: BlockTime,
+ parent_block_hash: BlockHash,
+ block_height: u64,
+ ) -> Self {
+ BlockInfo {
+ state_hash,
+ block_time,
+ parent_block_hash,
+ block_height,
+ }
+ }
+
+ /// Apply different state hash.
+ pub fn with_state_hash(&mut self, state_hash: Digest) {
+ self.state_hash = state_hash;
+ }
+
+ /// State hash.
+ pub fn state_hash(&self) -> Digest {
+ self.state_hash
+ }
+
+ /// Block time.
+ pub fn block_time(&self) -> BlockTime {
+ self.block_time
+ }
+
+ /// Parent block hash.
+ pub fn parent_block_hash(&self) -> BlockHash {
+ self.parent_block_hash
+ }
+
+ /// Block height.
+ pub fn block_height(&self) -> u64 {
+ self.block_height
+ }
+}
+
+/// A request to execute the given Wasm on the V1 runtime.
+#[derive(Debug)]
+pub struct WasmV1Request {
+ /// Block info.
+ pub block_info: BlockInfo,
  /// The hash identifying the transaction.
  pub transaction_hash: TransactionHash,
  /// The number of Motes per unit of Gas to be paid for execution.
@@ -92,8 +145,7 @@ pub struct WasmV1Request {
 
 impl WasmV1Request {
  pub(crate) fn new_from_executable_info(
- state_hash: Digest,
- block_time: BlockTime,
+ block_info: BlockInfo,
  gas_limit: Gas,
  transaction_hash: TransactionHash,
  initiator_addr: InitiatorAddr,
@@ -102,8 +154,7 @@ impl WasmV1Request {
  ) -> Self {
  let executable_item = executable_info.item();
  Self {
- state_hash,
- block_time,
+ block_info,
  transaction_hash,
  gas_limit,
  initiator_addr,
@@ -117,12 +168,11 @@ impl WasmV1Request {
 
  /// Creates a new request from a transaction for use as the session code.
  pub fn new_session(
- state_hash: Digest,
- block_time: BlockTime,
+ block_info: BlockInfo,
  gas_limit: Gas,
  transaction: &Transaction,
  ) -> Result<Self, InvalidRequest> {
- let info = match transaction {
+ let session_info = match transaction {
  Transaction::Deploy(deploy) => {
  SessionInfo::try_from((deploy.session(), deploy.hash()))?
  }
@@ -133,24 +183,22 @@ impl WasmV1Request {
  let initiator_addr = transaction.initiator_addr();
  let authorization_keys = transaction.signers();
  Ok(WasmV1Request::new_from_executable_info(
- state_hash,
- block_time,
+ block_info,
  gas_limit,
  transaction_hash,
  initiator_addr,
  authorization_keys,
- info,
+ session_info,
  ))
  }
 
  /// Creates a new request from a transaction for use as custom payment.
  pub fn new_custom_payment(
- state_hash: Digest,
- block_time: BlockTime,
+ block_info: BlockInfo,
  gas_limit: Gas,
  transaction: &Transaction,
  ) -> Result<Self, InvalidRequest> {
- let info = match transaction {
+ let payment_info = match transaction {
  Transaction::Deploy(deploy) => {
  PaymentInfo::try_from((deploy.payment(), deploy.hash()))?
  }
@@ -161,20 +209,18 @@ impl WasmV1Request {
  let initiator_addr = transaction.initiator_addr();
  let authorization_keys = transaction.signers();
  Ok(WasmV1Request::new_from_executable_info(
- state_hash,
- block_time,
+ block_info,
  gas_limit,
  transaction_hash,
  initiator_addr,
  authorization_keys,
- info,
+ payment_info,
  ))
  }
 
  /// Creates a new request from a deploy item for use as the session code.
  pub fn new_session_from_deploy_item(
- state_hash: Digest,
- block_time: BlockTime,
+ block_info: BlockInfo,
  gas_limit: Gas,
  DeployItem {
  ref address,
@@ -184,25 +230,23 @@ impl WasmV1Request {
  ..
  }: &DeployItem,
  ) -> Result<Self, InvalidRequest> {
- let info = SessionInfo::try_from((session, deploy_hash))?;
+ let session_info = SessionInfo::try_from((session, deploy_hash))?;
  let transaction_hash = TransactionHash::Deploy(*deploy_hash);
  let initiator_addr = InitiatorAddr::AccountHash(*address);
  let authorization_keys = authorization_keys.clone();
  Ok(WasmV1Request::new_from_executable_info(
- state_hash,
- block_time,
+ block_info,
  gas_limit,
  transaction_hash,
  initiator_addr,
  authorization_keys,
- info,
+ session_info,
  ))
  }
 
  /// Creates a new request from a deploy item for use as custom payment.
  pub fn new_custom_payment_from_deploy_item(
- state_hash: Digest,
- block_time: BlockTime,
+ block_info: BlockInfo,
  gas_limit: Gas,
  DeployItem {
  ref address,
@@ -212,18 +256,17 @@ impl WasmV1Request {
  ..
  }: &DeployItem,
  ) -> Result<Self, InvalidRequest> {
- let info = PaymentInfo::try_from((payment, deploy_hash))?;
+ let payment_info = PaymentInfo::try_from((payment, deploy_hash))?;
  let transaction_hash = TransactionHash::Deploy(*deploy_hash);
  let initiator_addr = InitiatorAddr::AccountHash(*address);
  let authorization_keys = authorization_keys.clone();
  Ok(WasmV1Request::new_from_executable_info(
- state_hash,
- block_time,
+ block_info,
  gas_limit,
  transaction_hash,
  initiator_addr,
  authorization_keys,
- info,
+ payment_info,
  ))
  }
 }

execution_engine/src/execution/error.rs

@@ -183,9 +183,9 @@ pub enum Error {
  /// The EntryPoints contains an invalid entry.
  #[error("The EntryPoints contains an invalid entry")]
  InvalidEntryPointType,
- /// Invalid message topic operation.
- #[error("The requested operation is invalid for a message topic")]
- InvalidMessageTopicOperation,
+ /// Invalid operation.
+ #[error("The imputed operation is invalid")]
+ InvalidImputedOperation,
  /// Invalid string encoding.
  #[error("Invalid UTF-8 string encoding: {0}")]
  InvalidUtf8Encoding(Utf8Error),

execution_engine/src/execution/executor.rs

@@ -7,13 +7,13 @@ use casper_storage::{
 };
 use casper_types::{
  account::AccountHash, addressable_entity::NamedKeys, contract_messages::Messages,
- execution::Effects, AddressableEntity, AddressableEntityHash, BlockTime, ContextAccessRights,
+ execution::Effects, AddressableEntity, AddressableEntityHash, ContextAccessRights,
  EntryPointType, Gas, Key, Phase, ProtocolVersion, RuntimeArgs, StoredValue, Tagged,
  TransactionHash, U512,
 };
 
 use crate::{
- engine_state::{execution_kind::ExecutionKind, EngineConfig, WasmV1Result},
+ engine_state::{execution_kind::ExecutionKind, BlockInfo, EngineConfig, WasmV1Result},
  execution::ExecError,
  runtime::{Runtime, RuntimeStack},
  runtime_context::{CallingAddContractVersion, RuntimeContext},
@@ -53,7 +53,7 @@ impl Executor {
  access_rights: ContextAccessRights,
  authorization_keys: BTreeSet<AccountHash>,
  account_hash: AccountHash,
- blocktime: BlockTime,
+ block_info: BlockInfo,
  txn_hash: TransactionHash,
  gas_limit: Gas,
  protocol_version: ProtocolVersion,
@@ -101,7 +101,7 @@ impl Executor {
  account_hash,
  address_generator,
  tracking_copy,
- blocktime,
+ block_info,
  protocol_version,
  txn_hash,
  phase,
@@ -163,7 +163,7 @@ impl Executor {
  account_hash: AccountHash,
  address_generator: Rc<RefCell<AddressGenerator>>,
  tracking_copy: Rc<RefCell<TrackingCopy<R>>>,
- blocktime: BlockTime,
+ block_info: BlockInfo,
  protocol_version: ProtocolVersion,
  txn_hash: TransactionHash,
  phase: Phase,
@@ -189,7 +189,7 @@ impl Executor {
  address_generator,
  tracking_copy,
  self.config.clone(),
- blocktime,
+ block_info,
  protocol_version,
  txn_hash,
  phase,

execution_engine/src/resolvers/v1_function_index.rs

@@ -60,6 +60,7 @@ pub(crate) enum FunctionIndex {
  ManageMessageTopic,
  EmitMessage,
  LoadCallerInformation,
+ GetBlockInfoIndex,
 }
 
 impl From<FunctionIndex> for usize {

execution_engine/src/resolvers/v1_resolver.rs

@@ -253,6 +253,10 @@ impl ModuleImportResolver for RuntimeModuleImportResolver {
  Signature::new(&[ValueType::I32; 4][..], Some(ValueType::I32)),
  FunctionIndex::EmitMessage.into(),
  ),
+ "casper_get_block_info" => FuncInstance::alloc_host(
+ Signature::new(&[ValueType::I32; 2][..], None),
+ FunctionIndex::GetBlockInfoIndex.into(),
+ ),
  _ => {
  return Err(InterpreterError::Function(format!(
  "host module doesn't export function with name {}",