Trait sp_core::crypto::Pair

pub trait Pair: CryptoType + Sized + Clone + Send + Sync + 'static {
    type Public: Public + Hash;
    type Seed: Default + AsRef<[u8]> + AsMut<[u8]> + Clone;
    type Signature: AsRef<[u8]>;
    type DeriveError;

    // Required methods
    fn generate_with_phrase(
        password: Option<&str>,
    ) -> (Self, String, Self::Seed);
    fn from_phrase(
        phrase: &str,
        password: Option<&str>,
    ) -> Result<(Self, Self::Seed), SecretStringError>;
    fn derive<Iter: Iterator<Item = DeriveJunction>>(
        &self,
        path: Iter,
        seed: Option<Self::Seed>,
    ) -> Result<(Self, Option<Self::Seed>), Self::DeriveError>;
    fn from_seed(seed: &Self::Seed) -> Self;
    fn from_seed_slice(seed: &[u8]) -> Result<Self, SecretStringError>;
    fn sign(&self, message: &[u8]) -> Self::Signature;
    fn verify<M: AsRef<[u8]>>(
        sig: &Self::Signature,
        message: M,
        pubkey: &Self::Public,
    ) -> bool;
    fn verify_weak<P: AsRef<[u8]>, M: AsRef<[u8]>>(
        sig: &[u8],
        message: M,
        pubkey: P,
    ) -> bool;
    fn public(&self) -> Self::Public;
    fn to_raw_vec(&self) -> Vec<u8> ;

    // Provided methods
    fn generate() -> (Self, Self::Seed) { ... }
    fn from_string_with_seed(
        s: &str,
        password_override: Option<&str>,
    ) -> Result<(Self, Option<Self::Seed>), SecretStringError> { ... }
    fn from_string(
        s: &str,
        password_override: Option<&str>,
    ) -> Result<Self, SecretStringError> { ... }
}

Trait suitable for typical cryptographic PKI key pair type.

For now it just specifies how to create a key from a phrase and derivation path.

Required Associated Types

type Public: Public + Hash

The type which is used to encode a public key.

type Seed: Default + AsRef<[u8]> + AsMut<[u8]> + Clone

The type used to (minimally) encode the data required to securely create a new key pair.

type Signature: AsRef<[u8]>

The type used to represent a signature. Can be created from a key pair and a message and verified with the message and a public key.

type DeriveError

Error returned from the derive function.

Required Methods

fn generate_with_phrase(password: Option<&str>) -> (Self, String, Self::Seed)

Generate new secure (random) key pair and provide the recovery phrase.

You can recover the same key later with from_phrase.

This is generally slower than generate(), so prefer that unless you need to persist the key from the current session.

fn from_phrase( phrase: &str, password: Option<&str>, ) -> Result<(Self, Self::Seed), SecretStringError>

Returns the KeyPair from the English BIP39 seed phrase, or None if it’s invalid.

fn derive<Iter: Iterator<Item = DeriveJunction>>( &self, path: Iter, seed: Option<Self::Seed>, ) -> Result<(Self, Option<Self::Seed>), Self::DeriveError>

Derive a child key from a series of given junctions.

fn from_seed(seed: &Self::Seed) -> Self

Generate new key pair from the provided seed.

@WARNING: THIS WILL ONLY BE SECURE IF THE seed IS SECURE. If it can be guessed by an attacker then they can also derive your key.

fn from_seed_slice(seed: &[u8]) -> Result<Self, SecretStringError>

Make a new key pair from secret seed material. The slice must be the correct size or it will return None.

@WARNING: THIS WILL ONLY BE SECURE IF THE seed IS SECURE. If it can be guessed by an attacker then they can also derive your key.

fn sign(&self, message: &[u8]) -> Self::Signature

Sign a message.

fn verify<M: AsRef<[u8]>>( sig: &Self::Signature, message: M, pubkey: &Self::Public, ) -> bool

Verify a signature on a message. Returns true if the signature is good.

fn verify_weak<P: AsRef<[u8]>, M: AsRef<[u8]>>( sig: &[u8], message: M, pubkey: P, ) -> bool

Verify a signature on a message. Returns true if the signature is good.

fn public(&self) -> Self::Public

Get the public key.

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

Return a vec filled with raw data.

Provided Methods

fn generate() -> (Self, Self::Seed)

Generate new secure (random) key pair.

This is only for ephemeral keys really, since you won’t have access to the secret key for storage. If you want a persistent key pair, use generate_with_phrase instead.

fn from_string_with_seed( s: &str, password_override: Option<&str>, ) -> Result<(Self, Option<Self::Seed>), SecretStringError>

Interprets the string s in order to generate a key Pair. Returns both the pair and an optional seed, in the case that the pair can be expressed as a direct derivation from a seed (some cases, such as Sr25519 derivations with path components, cannot).

This takes a helper function to do the key generation from a phrase, password and junction iterator.

• If s is a possibly 0x prefixed 64-digit hex string, then it will be interpreted directly as a MiniSecretKey (aka “seed” in subkey).
• If s is a valid BIP-39 key phrase of 12, 15, 18, 21 or 24 words, then the key will be derived from it. In this case:
  • the phrase may be followed by one or more items delimited by / characters.
  • the path may be followed by ///, in which case everything after the /// is treated as a password.
• If s begins with a / character it is prefixed with the Substrate public DEV_PHRASE and interpreted as above.

In this case they are interpreted as HDKD junctions; purely numeric items are interpreted as integers, non-numeric items as strings. Junctions prefixed with / are interpreted as soft junctions, and with // as hard junctions.

There is no correspondence mapping between SURI strings and the keys they represent. Two different non-identical strings can actually lead to the same secret being derived. Notably, integer junction indices may be legally prefixed with arbitrary number of zeros. Similarly an empty password (ending the SURI with ///) is perfectly valid and will generally be equivalent to no password at all.

None is returned if no matches are found.

fn from_string( s: &str, password_override: Option<&str>, ) -> Result<Self, SecretStringError>

Interprets the string s in order to generate a key pair.

See from_string_with_seed for more extensive documentation.

Object Safety

This trait is not object safe.

Implementors

impl Pair for sp_core::ecdsa::Pair

type Public = Public

type Seed = [u8; 32]

type Signature = Signature

type DeriveError = DeriveError

impl Pair for sp_core::ed25519::Pair

type Public = Public

type Seed = [u8; 32]

type Signature = Signature

type DeriveError = DeriveError

impl Pair for sp_core::sr25519::Pair

type Public = Public

type Seed = [u8; 32]

type Signature = Signature

type DeriveError = Infallible

impl Pair for Dummy

type Public = Dummy

type Seed = Dummy

type Signature = Dummy

type DeriveError = ()