/**
 * Carrier-style TURN credential derivation.
 *
 * Ported verbatim from the C SDK:
 *   ~/blockchain/ela/Elastos.NET.Carrier.Native.SDK/src/carrier/carrier_turnserver.c
 *
 * Every Carrier bootnode runs a TURN server on UDP/3478 with this exact
 * authentication scheme. Credentials are derived per request from a
 * freshly generated nonce and the ECDH shared key between our identity
 * keypair and the bootnode's identity public key:
 *
 *   shared_key = nacl.box.before(bootnode_pk, our_sk)        // X25519
 *   nonce      = 24 random bytes
 *   digest     = HMAC-SHA256(shared_key, nonce)
 *   username   = "{ourUserid}@{base58(nonce)}.auth.tox"
 *   password   = base58(digest)
 *   realm      = "elastos.org"
 *
 * The bootnode's TURN process knows its own secret key, can therefore
 * compute the same shared_key, reads `nonce` out of the username, and
 * recomputes the HMAC to verify our password.
 */
export declare const CARRIER_TURN_PORT = 3478;
export declare const CARRIER_TURN_REALM = "elastos.org";
export declare const CARRIER_TURN_USER_SUFFIX = "auth.tox";
export interface CarrierTurnCreds {
    host: string;
    port: number;
    realm: string;
    username: string;
    password: string;
}
export declare function deriveCarrierTurnCreds(opts: {
    bootnodeHost: string;
    bootnodePublicKey: Uint8Array;
    ourUserid: string;
    ourSecretKey: Uint8Array;
}): CarrierTurnCreds;