Struct PrivateKey 

pub struct PrivateKey { /* private fields */ }

A secp256k1 private key for signing and key derivation.

Wraps a k256 SigningKey and provides Bitcoin-specific functionality including WIF serialization, BRC-42 child derivation, and ECDH shared secrets.

Implementations

impl PrivateKey

pub fn new() -> Self

Generate a new random private key using the OS random number generator.

Returns

A new randomly generated PrivateKey.

pub fn from_bytes(bytes: &[u8]) -> Result<Self, PrimitivesError>

Create a private key from raw 32-byte scalar.

Arguments

• bytes - A 32-byte slice representing the private key scalar.

Returns

Ok(PrivateKey) if the bytes represent a valid scalar on secp256k1, or an error if the scalar is zero or out of range.

pub fn from_hex(hex_str: &str) -> Result<Self, PrimitivesError>

Create a private key from a hexadecimal string.

Arguments

• hex_str - A 64-character hex string representing the 32-byte scalar.

Returns

Ok(PrivateKey) on success, or an error if the hex is invalid or the scalar is invalid.

pub fn from_wif(wif: &str) -> Result<Self, PrimitivesError>

Create a private key from a WIF (Wallet Import Format) string.

Decodes the Base58Check-encoded string, validates the checksum, and extracts the 32-byte private key scalar.

Arguments

• wif - A Base58Check-encoded WIF string (compressed or uncompressed).

Returns

Ok(PrivateKey) on success, or an error if the WIF is malformed or the checksum fails.

pub fn to_wif(&self) -> String

Encode the private key as a WIF string with the mainnet prefix (0x80).

Always encodes for compressed public key format.

Returns

A Base58Check-encoded WIF string.

pub fn to_wif_prefix(&self, prefix: u8) -> String

Encode the private key as a WIF string with a custom network prefix.

Always encodes for compressed public key format.

Arguments

• prefix - The network prefix byte (0x80 for mainnet, 0xef for testnet).

Returns

A Base58Check-encoded WIF string.

pub fn to_bytes(&self) -> [u8; 32]

Serialize the private key as a 32-byte big-endian array.

Returns

A 32-byte array containing the private key scalar.

pub fn to_hex(&self) -> String

Serialize the private key as a lowercase hexadecimal string.

Returns

A 64-character hex string representing the 32-byte scalar.

pub fn pub_key(&self) -> PublicKey

Derive the corresponding public key for this private key.

Returns

The PublicKey corresponding to this private key.

pub fn sign(&self, hash: &[u8]) -> Result<Signature, PrimitivesError>

Sign a message hash using deterministic RFC6979 nonces.

The input should be a pre-computed hash (typically 32 bytes). Produces a low-S normalized signature per BIP-0062.

Arguments

• hash - The message hash to sign (should be 32 bytes).

Returns

Ok(Signature) on success, or an error if signing fails.

pub fn derive_shared_secret( &self, pub_key: &PublicKey, ) -> Result<PublicKey, PrimitivesError>

Compute an ECDH shared secret with another public key.

Multiplies the other party’s public key by this private key’s scalar, producing a shared EC point.

Arguments

• pub_key - The other party’s public key.

Returns

Ok(PublicKey) representing the shared secret point, or an error if the public key is not on the curve.

pub fn derive_child( &self, pub_key: &PublicKey, invoice_number: &str, ) -> Result<PrivateKey, PrimitivesError>

Derive a child private key using BRC-42 key derivation.

Computes an ECDH shared secret with the provided public key, then uses HMAC-SHA256 with the invoice number to derive a new private key scalar.

See BRC-42 spec: https://github.com/bitcoin-sv/BRCs/blob/master/key-derivation/0042.md

Arguments

• pub_key - The counterparty’s public key.
• invoice_number - The invoice number string used as HMAC data.

Returns

Ok(PrivateKey) with the derived child key, or an error if derivation fails.

Trait Implementations

impl Clone for PrivateKey

fn clone(&self) -> PrivateKey

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PrivateKey

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

Formats the value using the given formatter.

impl Default for PrivateKey

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for PrivateKey

fn eq(&self, other: &Self) -> 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 Eq for PrivateKey