import type { LedgerRecord } from './record.js';
/**
 * Optional ECDSA signing of ledger records. The hash chain alone is
 * tamper-EVIDENT: an attacker who edits a record must re-hash and re-link
 * everything after it, which is detectable but not preventable. A signature
 * over each record hash makes the ledger tamper-RESISTANT: re-hashed records
 * cannot be re-signed without the private key, so a full-rewrite attack fails
 * signature verification even when the rebuilt chain self-validates.
 *
 * Signatures cover the record HASH, not the record content: the hash already
 * binds every content field (see computeRecordHash), so signing it transitively
 * signs the content — and keeps `sig` itself outside the hashed material.
 */
export interface KeyPairPem {
    readonly privateKeyPem: string;
    readonly publicKeyPem: string;
}
export declare function generateKeyPair(): KeyPairPem;
/** Sign a record hash; returns the DER-encoded ECDSA signature as base64. */
export declare function signRecordHash(hashHex: string, privateKeyPem: string): string;
/** Verification is a predicate: any malformed input is simply not a valid signature. */
export declare function verifyRecordSignature(hashHex: string, signatureB64: string, publicKeyPem: string): boolean;
export interface SignatureCheck {
    /** False only on invalid signatures — unsigned records are a warning, not a failure. */
    readonly ok: boolean;
    readonly total: number;
    readonly signed: number;
    readonly verified: number;
    /** Records without `sig` (they predate the key or were written by an unkeyed store). */
    readonly unsigned: number;
    readonly invalidSeqs: readonly number[];
}
/**
 * Verify every signed record against the store's public key. Only meaningful
 * alongside verifyChain: this checks that each stored `hash` was signed by the
 * key holder, while the chain check proves `hash` still matches the content.
 */
export declare function verifyLedgerSignatures(records: readonly LedgerRecord[], publicKeyPem: string): SignatureCheck;