/**
 * PGP Key Signing Operations
 *
 * Provides RSA-PSS digital signature and verification functions.
 * Issue #1374
 */
/**
 * Sign raw bytes with an RSA-PSS private key
 *
 * @param data - Data to sign as Uint8Array
 * @param privateKey - CryptoKey configured for RSA-PSS signing
 * @returns Signature bytes (512 bytes for RSA-4096)
 */
export declare function signData(data: Uint8Array, privateKey: CryptoKey): Promise<Uint8Array>;
/**
 * Verify an RSA-PSS signature
 *
 * @param data - Original data that was signed
 * @param signature - Signature bytes to verify
 * @param publicKey - CryptoKey configured for RSA-PSS verification
 * @returns True if signature is valid, false otherwise
 */
export declare function verifySignature(data: Uint8Array, signature: Uint8Array, publicKey: CryptoKey): Promise<boolean>;
/**
 * Sign text and return base64-encoded signature
 *
 * Convenience wrapper that encodes text to UTF-8 bytes before signing.
 *
 * @param text - Text to sign
 * @param privateKey - CryptoKey configured for RSA-PSS signing
 * @returns Base64-encoded signature string
 */
export declare function signText(text: string, privateKey: CryptoKey): Promise<string>;
/**
 * Verify a base64-encoded signature for text
 *
 * Convenience wrapper that decodes base64 signature and encodes text to UTF-8.
 *
 * @param text - Original text that was signed
 * @param signatureBase64 - Base64-encoded signature to verify
 * @param publicKey - CryptoKey configured for RSA-PSS verification
 * @returns True if signature is valid, false otherwise
 */
export declare function verifyTextSignature(text: string, signatureBase64: string, publicKey: CryptoKey): Promise<boolean>;