Struct WasmLimits

#[non_exhaustive]
pub struct WasmLimits {
    pub initial_memory_limit_pages: Option<u32>,
    pub table_size_limit_elements: Option<u32>,
    pub max_imports: Option<usize>,
    pub max_functions: Option<usize>,
    pub max_function_params: Option<usize>,
    pub max_total_function_params: Option<usize>,
    pub max_function_results: Option<usize>,
}

Limits for static validation of Wasm files. These are checked before storing the Wasm file. All limits are optional because they are coming from the Go-side and have default values.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

initial_memory_limit_pages: Option<u32>

Maximum number of memory pages that a module can request.

Every Wasm memory has an initial size and an optional maximum size, both measured in Wasm pages. This limit applies to the initial size.

table_size_limit_elements: Option<u32>

The upper limit for the max value of each table. CosmWasm contracts have initial=max for 1 table. See

$ wasm-objdump --section=table -x packages/vm/testdata/hackatom.wasm
Section Details:

Table[1]:
- table[0] type=funcref initial=161 max=161

max_imports: Option<usize>

If the contract has more than this amount of imports, it will be rejected during static validation before even looking into the imports.

max_functions: Option<usize>

The maximum number of functions a contract can have. Any contract with more functions than this will be rejected during static validation.

max_function_params: Option<usize>

The maximum number of parameters a Wasm function can have.

max_total_function_params: Option<usize>

The maximum total number of parameters of all functions in the Wasm. For each function in the Wasm, take the number of parameters and sum all of these up. If that sum exceeds this limit, the Wasm will be rejected during static validation.

Be careful when adjusting this limit, as it prevents an attack where a small Wasm file explodes in size when compiled.

max_function_results: Option<usize>

The maximum number of results a Wasm function type can have.

Implementations

impl WasmLimits

pub fn initial_memory_limit_pages(&self) -> u32

pub fn table_size_limit_elements(&self) -> u32

pub fn max_imports(&self) -> usize

pub fn max_functions(&self) -> usize

pub fn max_function_params(&self) -> usize

pub fn max_total_function_params(&self) -> usize

pub fn max_function_results(&self) -> usize

Trait Implementations

impl Clone for WasmLimits

fn clone(&self) -> WasmLimits

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for WasmLimits

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

Formats the value using the given formatter.

impl Default for WasmLimits

fn default() -> WasmLimits

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for WasmLimits

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for WasmLimits

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.