Enum Tier 

#[non_exhaustive]
pub enum Tier {
    InProcess,
    Subprocess,
    Wasm,
    MicroVm,
}

How strongly a tool is isolated from the machine it runs on.

Ordered by strength, weakest first, and that ordering is load-bearing: Tier::weakest is how a flow’s overall isolation is summarised, and summarising it any other way would let one unconfined tool hide behind several confined ones.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

InProcess

In this process, sharing its address space. Trusted built-in tools only.

Subprocess

A jailed subprocess. The safe default for anything not written here.

Wasm

Wasmtime with WASI preopens. The Profile C tier.

MicroVm

A microVM. Scheduled after Wasm; named so the vocabulary is complete.

Implementations

impl Tier

pub const ALL: [Self; 4]

Every tier, weakest first.

pub const fn name(self) -> &'static str

The name used in a manifest, a plan, and a ledger entry.

pub const fn is_virtualising(self) -> bool

Whether this tier virtualises the tool’s view of the machine.

What Profile C asks for. In-process and subprocess do not: the first shares the address space, and the second shares the kernel’s namespaces unless something outside the tier has separated them.

pub const fn requires_trust(self) -> bool

Whether a tool has to be trusted for this tier to be safe.

True only in-process, and it is the whole reason that tier refuses anything not built in: a tool sharing this address space is not confined by anything at all, so the only control left is who wrote it.

pub const fn weaker(self, other: Self) -> Self

The weaker of two tiers.

pub fn weakest(tiers: impl IntoIterator<Item = Self>) -> Option<Self>

The weakest tier in a collection, if there is one.

How a flow’s isolation is reported. A flow is only as isolated as its least isolated tool, and saying anything else would let one in-process tool hide behind a dozen sandboxed ones.

Trait Implementations

impl Clone for Tier

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Tier

impl Debug for Tier

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

Formats the value using the given formatter.

impl Default for Tier

The safe default: anything that did not say gets a subprocess.

D1 calls process isolation “the safe default for untrusted code”, and a manifest that forgot to declare is exactly the case that needs one. Defaulting to in-process would mean a forgotten field silently bought full trust.

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Tier

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Tier

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

Formats the value using the given formatter.

impl Eq for Tier

impl Hash for Tier

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Tier

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

fn clamp_to<R>(self, range: R) -> Self

where Self: Sized, R: ClampBounds<Self>,

🔬This is a nightly-only experimental API. (clamp_to)

Restrict a value to a certain range.

impl PartialEq for Tier

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

Equality operator ==.

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

Inequality operator !=.

impl PartialOrd for Tier

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for Tier

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Tier