Struct DecodeLimits 

pub struct DecodeLimits {
    pub max_input_bytes: usize,
    pub max_list_items: usize,
    pub max_nesting_depth: usize,
    pub max_total_allocation: usize,
    pub max_proof_nodes: usize,
    pub max_total_items: usize,
}

Resource limits required by every untrusted decoder.

Fields

max_input_bytes: usize

Maximum accepted input length in bytes.

max_list_items: usize

Maximum items accepted in any single decoded list.

max_nesting_depth: usize

Maximum nested list depth.

RLP list decoding is also capped by crate::MAX_RLP_LIST_TRAVERSAL_DEPTH, even when this configured limit is higher.

max_total_allocation: usize

Maximum total allocation a decoder may request.

max_proof_nodes: usize

Maximum proof nodes accepted by a proof decoder.

max_total_items: usize

Maximum total decoded items visited by one decoder invocation.

Implementations

impl DecodeLimits

pub const DEPLOYMENT_STARTING_POINT: Self

Starting point for externally reachable wire decoders.

Using this constant unchanged in production is a security misconfiguration. Changing only one field is likely also a misconfiguration. Copy it, review every limit against the deployment’s concurrency, memory, and protocol policy, and tighten values before release.

pub const fn reviewed_policy( max_input_bytes: usize, max_list_items: usize, max_nesting_depth: usize, max_total_allocation: usize, max_proof_nodes: usize, max_total_items: usize, ) -> Self

Creates a reviewed deployment policy from explicit values.

This helper intentionally has no defaults. Production deployments should pass every value from their own concurrency, memory, and protocol review instead of copying Self::DEPLOYMENT_STARTING_POINT and changing one field.

pub fn check_input_len(self, len: usize) -> Result<(), DecodeError>

Validates the input length before parsing starts.

pub fn check_list_count(self, count: usize) -> Result<(), DecodeError>

Validates a decoded list item count.

pub fn check_nesting_depth(self, depth: usize) -> Result<(), DecodeError>

Validates the current nesting depth.

RLP list decoding also enforces crate::MAX_RLP_LIST_TRAVERSAL_DEPTH as a hard traversal-stack cap.

pub fn check_single_allocation_limit( self, size: usize, ) -> Result<(), DecodeError>

Validates one requested allocation against the allocation budget.

This helper is for single-allocation checks only. Decoders that can make more than one allocation must use DecodeAccumulator to enforce the cumulative budget.

pub fn check_proof_node_count(self, count: usize) -> Result<(), DecodeError>

Validates one proof-node count against the proof-node budget.

Decoders that traverse more than one proof segment must use DecodeAccumulator::account_proof_nodes for cumulative accounting.

pub fn check_item_count(self, count: usize) -> Result<(), DecodeError>

Validates one decoded item count against the cumulative item budget.

This helper is for single-count checks only. Decoders that visit items incrementally must use DecodeAccumulator::account_items.

pub const fn accumulator(self) -> DecodeAccumulator

Starts stateful budget accounting for a decoder invocation.

pub fn validate_deployment_policy(self) -> Result<(), DecodeError>

Rejects use of the unchanged deployment starting point as a production policy.

This is an identity check against the starter template. Changing only one field is likely also a misconfiguration. Review every limit against the deployment’s concurrency, memory, and protocol constraints before treating a policy as production-ready.

Trait Implementations

impl Clone for DecodeLimits

fn clone(&self) -> DecodeLimits

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for DecodeLimits

impl Debug for DecodeLimits

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for DecodeLimits

impl PartialEq for DecodeLimits

fn eq(&self, other: &DecodeLimits) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for DecodeLimits