Struct SmtProof 

pub struct SmtProof { /* private fields */ }

A proof which can be used to assert presence (or absence) of key-value pairs in a super::Smt (Sparse Merkle Tree).

The proof consists of a sparse Merkle path and a leaf, which describes the node located at the base of the path.

Implementations

impl SmtProof

pub fn new( path: SparseMerklePath, leaf: SmtLeaf, ) -> Result<SmtProof, SmtProofError>

Returns a new instance of SmtProof instantiated from the specified path and leaf.

Errors

Returns an error if the path length does not match the expected SMT_DEPTH, which would make the proof invalid.

pub fn verify_presence( &self, key: &Word, value: &Word, root: &Word, ) -> Result<(), SmtProofError>

Verifies that a super::Smt with the specified root contains the provided key-value pair.

Errors

• SmtProofError::InvalidKeyForProof if the key maps to a different leaf index than this proof’s leaf.
• SmtProofError::ConflictingRoots if the computed root doesn’t match the expected root.
• SmtProofError::ValueMismatch if the value doesn’t match the value in the leaf.

pub fn verify_unset(&self, key: &Word, root: &Word) -> Result<(), SmtProofError>

Verifies that a super::Smt with the specified root does not contain any value for the provided key (i.e., the key is unset).

This is equivalent to calling verify_presence(key, &EMPTY_WORD, root), but makes the intent clearer.

Errors

• SmtProofError::InvalidKeyForProof if the key maps to a different leaf index than this proof’s leaf.
• SmtProofError::ConflictingRoots if the computed root doesn’t match the expected root.
• SmtProofError::ValueMismatch if the key has a value in the tree (i.e., is not empty).

pub fn verify_absence( &self, key: &Word, value: &Word, root: &Word, ) -> Result<(), SmtProofError>

Verifies that a specific key-value pair is not in the tree.

This succeeds if the key exists with a different value, or if the key is unset.

Errors

• SmtProofError::InvalidKeyForProof if the key maps to a different leaf index than this proof’s leaf.
• SmtProofError::ConflictingRoots if the computed root doesn’t match the expected root.
• SmtProofError::ValuePresent if the key-value pair exists in the tree.

pub fn get(&self, key: &Word) -> Option<Word>

Returns the value associated with the specific key according to this proof, or None if this proof does not contain a value for the specified key.

A key-value pair generated by using this method should pass the verify_presence() check.

pub fn compute_root(&self) -> Word

Computes the root of a super::Smt to which this proof resolves.

pub fn path(&self) -> &SparseMerklePath

Returns the proof’s sparse Merkle path.

pub fn leaf(&self) -> &SmtLeaf

Returns the leaf associated with the proof.

pub fn authenticated_nodes(&self) -> impl Iterator<Item = InnerNodeInfo>

Returns an iterator over every inner node of this proof’s merkle path.

pub fn into_parts(self) -> (SparseMerklePath, SmtLeaf)

Consume the proof and returns its parts.

Trait Implementations

impl Clone for SmtProof

fn clone(&self) -> SmtProof

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SmtProof

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

Formats the value using the given formatter.

impl Deserializable for SmtProof

fn read_from<R>(source: &mut R) -> Result<SmtProof, DeserializationError>

where R: ByteReader,

Reads a sequence of bytes from the provided source, attempts to deserialize these bytes into Self, and returns the result.

fn min_serialized_size() -> usize

Returns the minimum serialized size for one instance of this type.

fn read_from_bytes(bytes: &[u8]) -> Result<Self, DeserializationError>

Attempts to deserialize the provided bytes into Self and returns the result.

fn read_from_bytes_with_budget( bytes: &[u8], budget: usize, ) -> Result<Self, DeserializationError>

Deserializes Self from bytes with a byte budget limit.

impl PartialEq for SmtProof

fn eq(&self, other: &SmtProof) -> 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 Serializable for SmtProof

fn write_into<W>(&self, target: &mut W)

where W: ByteWriter,

Serializes self into bytes and writes these bytes into the target.

fn to_bytes(&self) -> Vec<u8>

Serializes self into a vector of bytes.

fn get_size_hint(&self) -> usize

Returns an estimate of how many bytes are needed to represent self.

impl Eq for SmtProof

impl StructuralPartialEq for SmtProof