Module check 

Transaction checks.

Code in this file can freely assume that no pre-V4 transactions are present.

Constants

MAX_P2SH_SIGOPS

The maximum number of signature operations in the redeem script of a standard P2SH input.

MAX_STANDARD_SCRIPTSIG_SIZE

The maximum size in bytes of the scriptSig of a standard transaction input.

Functions

are_inputs_standard

Returns true if all of a transaction’s transparent inputs are standard.

check_for_duplicates 🔒

Check for duplicate items in a collection.

coinbase_expiry_height

Returns Ok(()) if the expiry height for the coinbase transaction is valid according to specifications 7.1 and ZIP-203.

coinbase_orchard_component_empty

Checks that a coinbase transaction has an empty Orchard component from NU6.3 onward.

coinbase_outputs_are_decryptable

Checks compatibility with ZIP-212 shielded Sapling and Orchard coinbase output decryption

coinbase_tx_no_prevout_joinsplit_spend

Check that a coinbase transaction has no PrevOut inputs, JoinSplits, or spends.

consensus_branch_id

Checks the nConsensusBranchId field.

count_script_push_ops 🔒

Count the number of push operations in a script.

disabled_add_to_sprout_pool

Check if a transaction is adding to the sprout pool after Canopy network upgrade given a block height and a network.

extract_p2sh_redeemed_script 🔒

Extract the redeemed script bytes from a P2SH scriptSig.

has_enough_ironwood_flags

Checks that a transaction with Ironwood actions has at least one Ironwood flag set.

has_enough_orchard_flags

Checks that the transaction has enough orchard flags.

has_inputs_and_outputs

Checks that the transaction has inputs and outputs.

joinsplit_has_vpub_zero

Check if JoinSplits in the transaction have one of its v_{pub} values equal to zero.

lock_time_has_passed

Checks if the transaction’s lock time allows this transaction to be included in a block.

mempool_standard_input_scripts

Standardness (policy) checks on a mempool transaction’s transparent input scripts, applied before the transaction is dispatched to script verification. The goal is to avoid the expensive verification for non-standard transactions which would be rejected anyway by Storage::reject_if_non_standard_tx(); this is a subset of the checks in that function.

non_coinbase_expiry_height

Returns Ok(()) if the expiry height for a non coinbase transaction is valid according to specifications 7.1 and ZIP-203.

orchard_cross_address_disabled

Checks that the Orchard pool does not enable cross-address transfers (NU6.3 onward).

orchard_value_balance_non_negative

Checks that no net new value is shielded into the Orchard pool from NU6.3 onward.

script_sig_args_expected 🔒

Returns the expected number of scriptSig arguments for a given script kind.

spend_conflicts

Check if a transaction has any internal spend conflicts.

standard_script_kind

Classify a script using the zcash_script solver.

tx_transparent_coinbase_spends_maturity

Accepts a transaction, block height, block UTXOs, and the transaction’s spent UTXOs from the chain.

validate_expiry_height_max 🔒

Checks that the expiry height of a transaction does not exceed the maximal value.

validate_expiry_height_mined 🔒

Checks that a transaction does not exceed its expiry height.