Struct DerivData 

pub struct DerivData<C: DklsCurve> {
    pub depth: u8,
    pub child_number: u32,
    pub parent_fingerprint: Fingerprint,
    pub poly_point: C::Scalar,
    pub pk: C::AffinePoint,
    pub chain_code: ChainCode,
}

Contains all the data needed for derivation.

The values that are really needed are only poly_point, pk and chain_code, but we also include the other ones if someone wants to retrieve the full extended public key as in BIP-32. The only field missing is the one for the network, but it can be easily inferred from context.

Fields

depth: u8

Counts after how many derivations this key is obtained from the master node.

child_number: u32

Index used to obtain this key from its parent.

parent_fingerprint: Fingerprint

Identifier of the parent key.

poly_point: C::Scalar

Behaves as the secret key share.

pk: C::AffinePoint

Public key.

chain_code: ChainCode

Extra entropy given by BIP-32.

Implementations

impl<C: DklsCurve> DerivData<C>

pub fn child_tweak( &self, child_number: u32, ) -> Result<(C::Scalar, ChainCode, Fingerprint), ErrorDeriv>

Computes the “tweak” needed to derive a secret key. In the process, it also produces the chain code and the parent fingerprint.

This is an adaptation of ckd_pub_tweak from the repository: https://github.com/rust-bitcoin/rust-bitcoin/blob/master/bitcoin/src/bip32.rs.

Errors

Will return Err if the HMAC result is too big (very unlikely).

pub fn derive_child( &self, child_number: u32, ) -> Result<DerivData<C>, ErrorDeriv>

Derives an instance of DerivData given a child number.

Errors

Will return Err if the depth is already at the maximum value, if the child number is invalid or if child_tweak fails. It will also fail if the new public key is invalid (very unlikely).

pub fn derive_from_path(&self, path: &str) -> Result<DerivData<C>, ErrorDeriv>

Derives an instance of DerivData following a path on the “key tree”.

See https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki for the description of a possible path (and don’t forget that hardened derivations are not implemented).

Errors

Will return Err if the path is invalid or if derive_child fails.

Trait Implementations

impl<C: Clone + DklsCurve> Clone for DerivData<C>

where C::Scalar: Clone, C::AffinePoint: Clone,

fn clone(&self) -> DerivData<C>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<C: Debug + DklsCurve> Debug for DerivData<C>

where C::Scalar: Debug, C::AffinePoint: Debug,

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

Formats the value using the given formatter.

impl<'de, C: DklsCurve> Deserialize<'de> for DerivData<C>

where C::AffinePoint: Deserialize<'de>, C::Scalar: Deserialize<'de>,

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<C: DklsCurve> Drop for DerivData<C>

fn drop(&mut self)

Executes the destructor for this type.

impl<C: DklsCurve> Serialize for DerivData<C>

where C::AffinePoint: Serialize, C::Scalar: Serialize,

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl<C: DklsCurve> Zeroize for DerivData<C>

fn zeroize(&mut self)

Zero out this object from memory using Rust intrinsics which ensure the zeroization operation is not “optimized away” by the compiler.