purify::puresign_plusplus::PreparedNonce Class Reference

Move-only prepared nonce bound to either a message or a topic. More...

#include <bppp.hpp>

Public Types
enum class	Scope : std::uint8_t { Message , Topic }

Public Member Functions
	PreparedNonce (const PreparedNonce &)=delete
PreparedNonce &	operator= (const PreparedNonce &)=delete
	PreparedNonce (PreparedNonce &&other) noexcept
PreparedNonce &	operator= (PreparedNonce &&other) noexcept
	~PreparedNonce ()
const Nonce &	public_nonce () const noexcept
	Returns the public nonce corresponding to this prepared secret nonce scalar.
Scalar32	scalar () const
	Explicitly exports the secret nonce scalar.
Result< Signature >	sign_message (const Bip340Key &signer, std::span< const unsigned char > message, purify_secp_context *secp_context) &&
	Consumes this message-bound nonce and signs the matching message.
Result< Signature >	sign_topic_message (const Bip340Key &signer, std::span< const unsigned char > message, purify_secp_context *secp_context) &&
	Consumes this topic-bound nonce and signs a message under that topic binding.

Static Public Member Functions
static PreparedNonce	from_parts (Scope scope, const Scalar32 &scalar, const Nonce &nonce, const XOnly32 &signer_pubkey, const XOnly32 &binding_digest)
	Builds a prepared nonce from already-derived nonce components.

Detailed Description

The public nonce is safe to send over the wire. The secret scalar is intentionally not serializable and is wiped on destruction and after moves.

Definition at line 284 of file bppp.hpp.

Member Enumeration Documentation

Scope

enum class purify::puresign_plusplus::PreparedNonce::Scope : std::uint8_t

strong

Enumerator
Message
Topic

Definition at line 286 of file bppp.hpp.

Constructor & Destructor Documentation

PreparedNonce() [1/2]

purify::puresign_plusplus::PreparedNonce::PreparedNonce ( const PreparedNonce &  )

delete

PreparedNonce() [2/2]

purify::puresign_plusplus::PreparedNonce::PreparedNonce ( PreparedNonce &&  other )

noexcept

Definition at line 311 of file bppp.cpp.

~PreparedNonce()

purify::puresign_plusplus::PreparedNonce::~PreparedNonce

(

)

Definition at line 330 of file bppp.cpp.

Member Function Documentation

from_parts()

PreparedNonce purify::puresign_plusplus::PreparedNonce::from_parts ( Scope  scope, const Scalar32 &  scalar, const Nonce &  nonce, const XOnly32 &  signer_pubkey, const XOnly32 &  binding_digest  )

static

Parameters

scope	Whether the nonce is message-bound or topic-bound.
scalar	The secret nonce scalar to store.
nonce	The public x-only nonce corresponding to scalar.
signer_pubkey	The signer's BIP340 x-only public key.
binding_digest	The binding digest that this nonce must later match.

Returns

The constructed move-only prepared nonce.

Definition at line 306 of file bppp.cpp.

References binding_digest, nonce, scalar(), scope, and signer_pubkey.

Referenced by purify::puresign_plusplus::api_impl::prepare_message_nonce(), purify::puresign_plusplus::api_impl::prepare_message_nonce_with_proof(), purify::puresign_plusplus::api_impl::prepare_message_nonce_with_proof(), purify::puresign_plusplus::api_impl::prepare_topic_nonce(), purify::puresign_plusplus::api_impl::prepare_topic_nonce_with_proof(), and purify::puresign_plusplus::api_impl::prepare_topic_nonce_with_proof().

operator=() [1/2]

PreparedNonce & purify::puresign_plusplus::PreparedNonce::operator= ( const PreparedNonce &  )

delete

operator=() [2/2]

PreparedNonce & purify::puresign_plusplus::PreparedNonce::operator= ( PreparedNonce &&  other )

noexcept

Definition at line 317 of file bppp.cpp.

public_nonce()

const Nonce & purify::puresign_plusplus::PreparedNonce::public_nonce ( ) const

inlinenoexcept

Returns

The x-only public nonce that is safe to share with a verifier.

Definition at line 302 of file bppp.hpp.

Referenced by purify::puresign_plusplus::api_impl::prepare_message_nonce_with_proof(), purify::puresign_plusplus::api_impl::prepare_message_nonce_with_proof(), purify::puresign_plusplus::api_impl::prepare_topic_nonce_with_proof(), purify::puresign_plusplus::api_impl::prepare_topic_nonce_with_proof(), and purify::puresign_plusplus::PreparedNonceWithProof::public_nonce().

scalar()

Scalar32 purify::puresign_plusplus::PreparedNonce::scalar ( ) const

inline

This is intentionally a copy-returning accessor so callers have to opt in to handling the secret value.

Definition at line 312 of file bppp.hpp.

Referenced by from_parts(), and purify::puresign_plusplus::PreparedNonceWithProof::scalar().

sign_message()

Result< Signature > purify::puresign_plusplus::PreparedNonce::sign_message	(	const Bip340Key &	signer,
		std::span< const unsigned char >	message,
		purify_secp_context *	secp_context
	)		&&

Parameters

signer	The BIP340 signer derived from the same secret as this prepared nonce.
message	The message that must match the nonce binding.

Returns

The resulting BIP340 signature.

Definition at line 338 of file bppp.cpp.

References purify::BackendRejectedInput, binding_digest, purify::BindingMismatch, purify::InternalMismatch, purify_bip340_sign_with_fixed_nonce(), purify_bip340_verify(), PURIFY_RETURN_IF_ERROR, purify::require_secp_context(), and purify::unexpected_error().

sign_topic_message()

Result< Signature > purify::puresign_plusplus::PreparedNonce::sign_topic_message	(	const Bip340Key &	signer,
		std::span< const unsigned char >	message,
		purify_secp_context *	secp_context
	)		&&

Parameters

signer	The BIP340 signer derived from the same secret as this prepared nonce.
message	The message to sign.

Returns

The resulting BIP340 signature.

Definition at line 368 of file bppp.cpp.

References purify::BackendRejectedInput, purify::BindingMismatch, purify::InternalMismatch, purify_bip340_sign_with_fixed_nonce(), purify_bip340_verify(), PURIFY_RETURN_IF_ERROR, purify::require_secp_context(), and purify::unexpected_error().

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The documentation for this class was generated from the following files:

• include/purify/puresign/bppp.hpp
• src/puresign/bppp.cpp