sgns::neoswarm::security::MessageSigning

Signs and verifies inter-node message payloads.

#include <message_signing.hpp>

Public Functions

	Name
	MessageSigning(const NodeIdentity & identity) Construct with a reference to the local node identity.
outcome::result< std::vector< uint8_t > >	Sign(const std::string & payload) const Sign a serialised message payload.
std::string	AttachSignature(const std::string & payload) const Attach a signature field to a JSON payload string.
bool	Verify(const std::string & payload, const std::vector< uint8_t > & signature, const std::string & m_pubKeyhex) Verify a signature against a known public key.
std::string	GenerateNonce() Generate a cryptographically random nonce.
uint64_t	CurrentTimestampMs() Get current Unix timestamp in milliseconds.
bool	VerifyAndStrip(std::string & payload, const std::string & m_pubKeyhex) Verify and strip the signature field from a signed JSON payload.

Public Attributes

	Name
constexpr int64_t	kReplayWindowSec Replay protection window in seconds.

Public Functions Documentation

function MessageSigning

explicit MessageSigning(
    const NodeIdentity & identity
)

Construct with a reference to the local node identity.

Parameters:

• identity Node identity used for signing.

function Sign

outcome::result< std::vector< uint8_t > > Sign(
    const std::string & payload
) const

Sign a serialised message payload.

Parameters:

• payload UTF-8 payload string.

Return: DER-encoded signature bytes or IdentityError.

function AttachSignature

std::string AttachSignature(
    const std::string & payload
) const

Attach a signature field to a JSON payload string.

Parameters:

• payload JSON object string (must end with '}').

Return: Payload with appended "sig" field.

function Verify

static bool Verify(
    const std::string & payload,
    const std::vector< uint8_t > & signature,
    const std::string & m_pubKeyhex
)

Verify a signature against a known public key.

Parameters:

• payload Original payload string.
• signature DER-encoded signature bytes.
• m_pubKeyhex Hex-encoded compressed public key of the signer.

Return: True if the signature is valid.

function GenerateNonce

static std::string GenerateNonce()

Generate a cryptographically random nonce.

Return: Hex-encoded 32-byte nonce.

function CurrentTimestampMs

static uint64_t CurrentTimestampMs()

Get current Unix timestamp in milliseconds.

Return: Milliseconds since epoch.

function VerifyAndStrip

static bool VerifyAndStrip(
    std::string & payload,
    const std::string & m_pubKeyhex
)

Verify and strip the signature field from a signed JSON payload.

Parameters:

• payload On entry: signed JSON. On exit: payload without sig.
• m_pubKeyhex Hex-encoded public key of the expected signer.

Return: True if the signature is valid.

Public Attributes Documentation

variable kReplayWindowSec

static constexpr int64_t kReplayWindowSec = 30;

Replay protection window in seconds.

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Updated on 2026-07-25 at 22:56:56 +0000