Struct SigningKey

pub struct SigningKey<C>
where
    C: PrimeCurve + CurveArithmetic,
    Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>,
    SignatureSize<C>: ArrayLength<u8>,
{ /* private fields */ }

Available on crate feature signing only.

ECDSA secret key used for signing. Generic over prime order elliptic curves (e.g. NIST P-curves)

Requires an elliptic_curve::CurveArithmetic impl on the curve, and a SignPrimitive impl on its associated Scalar type.

Usage

The signature crate defines the following traits which are the primary API for signing:

• Signer: sign a message using this key
• DigestSigner: sign the output of a Digest using this key
• PrehashSigner: sign the low-level raw output bytes of a message digest

See the p256 crate for examples of using this type with a concrete elliptic curve.

Implementations

impl<C> SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

pub fn sign_prehash_recoverable( &self, prehash: &[u8], ) -> Result<(Signature<C>, RecoveryId)>

Sign the given message prehash, returning a signature and recovery ID.

pub fn sign_digest_recoverable<D>( &self, msg_digest: D, ) -> Result<(Signature<C>, RecoveryId)>

where D: Digest,

Sign the given message digest, returning a signature and recovery ID.

pub fn sign_recoverable(&self, msg: &[u8]) -> Result<(Signature<C>, RecoveryId)>

Sign the given message, hashing it with the curve’s default digest function, and returning a signature and recovery ID.

impl<C> SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

pub fn random(rng: &mut impl CryptoRngCore) -> Self

Generate a cryptographically random SigningKey.

pub fn from_bytes(bytes: &FieldBytes<C>) -> Result<Self>

Initialize signing key from a raw scalar serialized as a byte array.

pub fn from_slice(bytes: &[u8]) -> Result<Self>

Initialize signing key from a raw scalar serialized as a byte slice.

pub fn to_bytes(&self) -> FieldBytes<C>

Serialize this SigningKey as bytes

pub fn as_nonzero_scalar(&self) -> &NonZeroScalar<C>

Borrow the secret NonZeroScalar value for this key.

⚠️ Warning

This value is key material.

Please treat it with the care it deserves!

pub fn verifying_key(&self) -> &VerifyingKey<C>

Available on crate feature verifying only.

Get the VerifyingKey which corresponds to this SigningKey.

Trait Implementations

impl<C> AsRef<VerifyingKey<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Available on crate feature verifying only.

fn as_ref(&self) -> &VerifyingKey<C>

Converts this type into a shared reference of the (usually inferred) input type.

impl<C> AssociatedAlgorithmIdentifier for SigningKey<C>

where C: AssociatedOid + CurveArithmetic + PrimeCurve, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Available on crate feature pkcs8 only.

const ALGORITHM_IDENTIFIER: AlgorithmIdentifier<ObjectIdentifier> = SecretKey<C>::ALGORITHM_IDENTIFIER

AlgorithmIdentifier for this structure.

type Params = ObjectIdentifier

Algorithm parameters.

impl<C> Clone for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + Clone, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

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

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<C> ConstantTimeEq for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn ct_eq(&self, other: &Self) -> Choice

Determine if two items are equal.

fn ct_ne(&self, other: &Self) -> Choice

Determine if two items are NOT equal.

impl<C> Debug for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

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

Formats the value using the given formatter.

impl<C, D> DigestSigner<D, (Signature<C>, RecoveryId)> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, D: Digest, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn try_sign_digest(&self, msg_digest: D) -> Result<(Signature<C>, RecoveryId)>

Attempt to sign the given prehashed message Digest, returning a digital signature on success, or an error if something went wrong.

fn sign_digest(&self, digest: D) -> S

Sign the given prehashed message Digest, returning a signature.

impl<C, D> DigestSigner<D, Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, D: Digest + FixedOutput<OutputSize = FieldBytesSize<C>>, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Sign message digest using a deterministic ephemeral scalar (k) computed using the algorithm described in RFC6979 § 3.2.

fn try_sign_digest(&self, msg_digest: D) -> Result<Signature<C>>

Attempt to sign the given prehashed message Digest, returning a digital signature on success, or an error if something went wrong.

fn sign_digest(&self, digest: D) -> S

Sign the given prehashed message Digest, returning a signature.

impl<C, D> DigestSigner<D, SignatureWithOid<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, D: AssociatedOid + Digest + FixedOutput<OutputSize = FieldBytesSize<C>>, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn try_sign_digest(&self, msg_digest: D) -> Result<SignatureWithOid<C>>

Attempt to sign the given prehashed message Digest, returning a digital signature on success, or an error if something went wrong.

fn sign_digest(&self, digest: D) -> S

Sign the given prehashed message Digest, returning a signature.

impl<C> Drop for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn drop(&mut self)

Executes the destructor for this type.

impl<C> EncodePrivateKey for SigningKey<C>

where C: AssociatedOid + PrimeCurve + CurveArithmetic, AffinePoint<C>: FromEncodedPoint<C> + ToEncodedPoint<C>, FieldBytesSize<C>: ModulusSize, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Available on crate feature pem only.

fn to_pkcs8_der(&self) -> Result<SecretDocument>

Serialize a SecretDocument containing a PKCS#8-encoded private key.

fn to_pkcs8_pem( &self, line_ending: LineEnding, ) -> Result<Zeroizing<String>, Error>

Serialize this private key as PEM-encoded PKCS#8 with the given LineEnding.

fn write_pkcs8_der_file(&self, path: impl AsRef<Path>) -> Result<(), Error>

Write ASN.1 DER-encoded PKCS#8 private key to the given path

fn write_pkcs8_pem_file( &self, path: impl AsRef<Path>, line_ending: LineEnding, ) -> Result<(), Error>

Write ASN.1 DER-encoded PKCS#8 private key to the given path

impl<C> From<&SecretKey<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn from(secret_key: &SecretKey<C>) -> Self

Converts to this type from the input type.

impl<C> From<&SigningKey<C>> for SecretKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn from(secret_key: &SigningKey<C>) -> Self

Converts to this type from the input type.

impl<C> From<&SigningKey<C>> for VerifyingKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Available on crate feature verifying only.

fn from(signing_key: &SigningKey<C>) -> VerifyingKey<C>

Converts to this type from the input type.

impl<C> From<NonZeroScalar<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn from(secret_scalar: NonZeroScalar<C>) -> Self

Converts to this type from the input type.

impl<C> From<SecretKey<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn from(secret_key: SecretKey<C>) -> Self

Converts to this type from the input type.

impl<C> From<SigningKey<C>> for SecretKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn from(key: SigningKey<C>) -> Self

Converts to this type from the input type.

impl<C> From<SigningKey<C>> for VerifyingKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Available on crate feature verifying only.

fn from(signing_key: SigningKey<C>) -> VerifyingKey<C>

Converts to this type from the input type.

impl<C> FromStr for SigningKey<C>

where C: PrimeCurve + AssociatedOid + CurveArithmetic, AffinePoint<C>: FromEncodedPoint<C> + ToEncodedPoint<C>, FieldBytesSize<C>: ModulusSize, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Available on crate feature pem only.

type Err = Error

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self>

Parses a string s to return a value of this type.

impl<C> KeypairRef for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Available on crate feature verifying only.

type VerifyingKey = VerifyingKey<C>

Verifying key type for this keypair.

impl<C> PartialEq for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn eq(&self, other: &SigningKey<C>) -> 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<C> PrehashSigner<(Signature<C>, RecoveryId)> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn sign_prehash(&self, prehash: &[u8]) -> Result<(Signature<C>, RecoveryId)>

Attempt to sign the given message digest, returning a digital signature on success, or an error if something went wrong.

impl<C> PrehashSigner<Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Sign message prehash using a deterministic ephemeral scalar (k) computed using the algorithm described in RFC6979 § 3.2.

fn sign_prehash(&self, prehash: &[u8]) -> Result<Signature<C>>

Attempt to sign the given message digest, returning a digital signature on success, or an error if something went wrong.

impl<C> PrehashSigner<Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>, MaxSize<C>: ArrayLength<u8>, <FieldBytesSize<C> as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,

Available on crate feature der only.

fn sign_prehash(&self, prehash: &[u8]) -> Result<Signature<C>>

Attempt to sign the given message digest, returning a digital signature on success, or an error if something went wrong.

impl<C, D> RandomizedDigestSigner<D, Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, D: Digest + FixedOutput<OutputSize = FieldBytesSize<C>>, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn try_sign_digest_with_rng( &self, rng: &mut impl CryptoRngCore, msg_digest: D, ) -> Result<Signature<C>>

Attempt to sign the given prehashed message Digest, returning a digital signature on success, or an error if something went wrong.

fn sign_digest_with_rng(&self, rng: &mut impl CryptoRngCore, digest: D) -> S

Sign the given prehashed message Digest, returning a signature.

impl<C, D> RandomizedDigestSigner<D, Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, D: Digest + FixedOutput<OutputSize = FieldBytesSize<C>>, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>, MaxSize<C>: ArrayLength<u8>, <FieldBytesSize<C> as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,

Available on crate feature der only.

fn try_sign_digest_with_rng( &self, rng: &mut impl CryptoRngCore, msg_digest: D, ) -> Result<Signature<C>>

Attempt to sign the given prehashed message Digest, returning a digital signature on success, or an error if something went wrong.

fn sign_digest_with_rng(&self, rng: &mut impl CryptoRngCore, digest: D) -> S

Sign the given prehashed message Digest, returning a signature.

impl<C> RandomizedPrehashSigner<Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn sign_prehash_with_rng( &self, rng: &mut impl CryptoRngCore, prehash: &[u8], ) -> Result<Signature<C>>

Attempt to sign the given message digest, returning a digital signature on success, or an error if something went wrong.

impl<C> RandomizedPrehashSigner<Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>, MaxSize<C>: ArrayLength<u8>, <FieldBytesSize<C> as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,

Available on crate feature der only.

fn sign_prehash_with_rng( &self, rng: &mut impl CryptoRngCore, prehash: &[u8], ) -> Result<Signature<C>>

Attempt to sign the given message digest, returning a digital signature on success, or an error if something went wrong.

impl<C> RandomizedSigner<Signature<C>> for SigningKey<C>

where Self: RandomizedDigestSigner<C::Digest, Signature<C>>, C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn try_sign_with_rng( &self, rng: &mut impl CryptoRngCore, msg: &[u8], ) -> Result<Signature<C>>

Attempt to sign the given message, returning a digital signature on success, or an error if something went wrong.

fn sign_with_rng(&self, rng: &mut impl CryptoRngCore, msg: &[u8]) -> S

Sign the given message and return a digital signature

impl<C> RandomizedSigner<Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>, MaxSize<C>: ArrayLength<u8>, <FieldBytesSize<C> as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,

Available on crate feature der only.

fn try_sign_with_rng( &self, rng: &mut impl CryptoRngCore, msg: &[u8], ) -> Result<Signature<C>>

Attempt to sign the given message, returning a digital signature on success, or an error if something went wrong.

fn sign_with_rng(&self, rng: &mut impl CryptoRngCore, msg: &[u8]) -> S

Sign the given message and return a digital signature

impl<C> SignatureAlgorithmIdentifier for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>, Signature<C>: AssociatedAlgorithmIdentifier<Params = AnyRef<'static>>,

Available on crate feature pkcs8 only.

const SIGNATURE_ALGORITHM_IDENTIFIER: AlgorithmIdentifier<Self::Params> = Signature<C>::ALGORITHM_IDENTIFIER

AlgorithmIdentifier for the corresponding singature system.

type Params = AnyRef<'static>

Algorithm parameters.

impl<C> Signer<(Signature<C>, RecoveryId)> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn try_sign(&self, msg: &[u8]) -> Result<(Signature<C>, RecoveryId)>

Attempt to sign the given message, returning a digital signature on success, or an error if something went wrong.

fn sign(&self, msg: &[u8]) -> S

Sign the given message and return a digital signature

impl<C> Signer<Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Sign message using a deterministic ephemeral scalar (k) computed using the algorithm described in RFC6979 § 3.2.

fn try_sign(&self, msg: &[u8]) -> Result<Signature<C>>

Attempt to sign the given message, returning a digital signature on success, or an error if something went wrong.

fn sign(&self, msg: &[u8]) -> S

Sign the given message and return a digital signature

impl<C> Signer<Signature<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>, MaxSize<C>: ArrayLength<u8>, <FieldBytesSize<C> as Add>::Output: Add<MaxOverhead> + ArrayLength<u8>,

Available on crate feature der only.

fn try_sign(&self, msg: &[u8]) -> Result<Signature<C>>

Attempt to sign the given message, returning a digital signature on success, or an error if something went wrong.

fn sign(&self, msg: &[u8]) -> S

Sign the given message and return a digital signature

impl<C> Signer<SignatureWithOid<C>> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic + DigestPrimitive, C::Digest: AssociatedOid, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

fn try_sign(&self, msg: &[u8]) -> Result<SignatureWithOid<C>>

Attempt to sign the given message, returning a digital signature on success, or an error if something went wrong.

fn sign(&self, msg: &[u8]) -> S

Sign the given message and return a digital signature

impl<C> TryFrom<&[u8]> for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

type Error = Error

The type returned in the event of a conversion error.

fn try_from(bytes: &[u8]) -> Result<Self>

Performs the conversion.

impl<C> TryFrom<PrivateKeyInfo<'_>> for SigningKey<C>

where C: PrimeCurve + AssociatedOid + CurveArithmetic, AffinePoint<C>: FromEncodedPoint<C> + ToEncodedPoint<C>, FieldBytesSize<C>: ModulusSize, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Available on crate feature pkcs8 only.

type Error = Error

The type returned in the event of a conversion error.

fn try_from(private_key_info: PrivateKeyInfo<'_>) -> Result<Self>

Performs the conversion.

impl<C> Eq for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,

Constant-time comparison

impl<C> ZeroizeOnDrop for SigningKey<C>

where C: PrimeCurve + CurveArithmetic, Scalar<C>: Invert<Output = CtOption<Scalar<C>>> + SignPrimitive<C>, SignatureSize<C>: ArrayLength<u8>,