import type TypedEventEmitter from 'typed-emitter'; import type { VideoCodec } from '../../room/track/options'; import { type CryptorCallbacks } from '../events'; import type { KeyProviderOptions } from '../types'; import type { ParticipantKeyHandler } from './ParticipantKeyHandler'; export declare const encryptionEnabledMap: Map; export interface FrameCryptorConstructor { new (opts?: unknown): BaseFrameCryptor; } export interface TransformerInfo { readable: ReadableStream; writable: WritableStream; transformer: TransformStream; trackId: string; symbol: symbol; } declare const BaseFrameCryptor_base: new () => TypedEventEmitter; export declare class BaseFrameCryptor extends BaseFrameCryptor_base { protected encodeFunction(encodedFrame: RTCEncodedVideoFrame | RTCEncodedAudioFrame, controller: TransformStreamDefaultController): Promise; protected decodeFunction(encodedFrame: RTCEncodedVideoFrame | RTCEncodedAudioFrame, controller: TransformStreamDefaultController): Promise; } /** * Cryptor is responsible for en-/decrypting media frames. * Each Cryptor instance is responsible for en-/decrypting a single mediaStreamTrack. */ export declare class FrameCryptor extends BaseFrameCryptor { private sendCounts; private participantIdentity; private trackId; private keys; private videoCodec?; private rtpMap; private keyProviderOptions; /** * used for detecting server injected unencrypted frames */ private sifTrailer; private detectedCodec?; private currentTransform?; /** * Throttling mechanism for decryption errors to prevent memory leaks */ private lastErrorTimestamp; private errorCounts; private readonly ERROR_THROTTLE_MS; private readonly MAX_ERRORS_PER_MINUTE; private readonly ERROR_WINDOW_MS; constructor(opts: { keys: ParticipantKeyHandler; participantIdentity: string; keyProviderOptions: KeyProviderOptions; sifTrailer?: Uint8Array; }); private get logContext(); /** * Assign a different participant to the cryptor. * useful for transceiver re-use * @param id * @param keys */ setParticipant(id: string, keys: ParticipantKeyHandler): void; unsetParticipant(): void; isEnabled(): boolean | undefined; getParticipantIdentity(): string | undefined; getTrackId(): string | undefined; /** * Update the video codec used by the mediaStreamTrack * @param codec */ setVideoCodec(codec: VideoCodec): void; /** * rtp payload type map used for figuring out codec of payload type when encoding * @param map */ setRtpMap(map: Map): void; setupTransform(operation: 'encode' | 'decode', readable: ReadableStream, writable: WritableStream, trackId: string, isReuse: boolean, codec?: VideoCodec): void; setSifTrailer(trailer: Uint8Array): void; /** * Checks if we should emit an error based on throttling rules to prevent memory leaks * @param errorKey - unique key identifying the error context * @returns true if the error should be emitted, false otherwise */ private shouldEmitError; /** * Emits a throttled error to prevent memory leaks from repeated decryption failures * @param error - the CryptorError to emit */ private emitThrottledError; /** * Function that will be injected in a stream and will encrypt the given encoded frames. * * @param {RTCEncodedVideoFrame|RTCEncodedAudioFrame} encodedFrame - Encoded video frame. * @param {TransformStreamDefaultController} controller - TransportStreamController. * * The VP8 payload descriptor described in * https://tools.ietf.org/html/rfc7741#section-4.2 * is part of the RTP packet and not part of the frame and is not controllable by us. * This is fine as the SFU keeps having access to it for routing. * * The encrypted frame is formed as follows: * 1) Find unencrypted byte length, depending on the codec, frame type and kind. * 2) Form the GCM IV for the frame as described above. * 3) Encrypt the rest of the frame using AES-GCM. * 4) Allocate space for the encrypted frame. * 5) Copy the unencrypted bytes to the start of the encrypted frame. * 6) Append the ciphertext to the encrypted frame. * 7) Append the IV. * 8) Append a single byte for the key identifier. * 9) Enqueue the encrypted frame for sending. */ protected encodeFunction(encodedFrame: RTCEncodedVideoFrame | RTCEncodedAudioFrame, controller: TransformStreamDefaultController): Promise; /** * Function that will be injected in a stream and will decrypt the given encoded frames. * * @param {RTCEncodedVideoFrame|RTCEncodedAudioFrame} encodedFrame - Encoded video frame. * @param {TransformStreamDefaultController} controller - TransportStreamController. */ protected decodeFunction(encodedFrame: RTCEncodedVideoFrame | RTCEncodedAudioFrame, controller: TransformStreamDefaultController): Promise; /** * Function that will decrypt the given encoded frame. If the decryption fails, it will * ratchet the key for up to RATCHET_WINDOW_SIZE times. */ private decryptFrame; /** * Construct the IV used for AES-GCM and sent (in plain) with the packet similar to * https://tools.ietf.org/html/rfc7714#section-8.1 * It concatenates * - the 32 bit synchronization source (SSRC) given on the encoded frame, * - the 32 bit rtp timestamp given on the encoded frame, * - a send counter that is specific to the SSRC. Starts at a random number. * The send counter is essentially the pictureId but we currently have to implement this ourselves. * There is no XOR with a salt. Note that this IV leaks the SSRC to the receiver but since this is * randomly generated and SFUs may not rewrite this is considered acceptable. * The SSRC is used to allow demultiplexing multiple streams with the same key, as described in * https://tools.ietf.org/html/rfc3711#section-4.1.1 * The RTP timestamp is 32 bits and advances by the codec clock rate (90khz for video, 48khz for * opus audio) every second. For video it rolls over roughly every 13 hours. * The send counter will advance at the frame rate (30fps for video, 50fps for 20ms opus audio) * every second. It will take a long time to roll over. * * See also https://developer.mozilla.org/en-US/docs/Web/API/AesGcmParams */ private makeIV; private getUnencryptedBytes; /** * inspects frame payloadtype if available and maps it to the codec specified in rtpMap */ private getVideoCodec; } /** * we use a magic frame trailer to detect whether a frame is injected * by the livekit server and thus to be treated as unencrypted * @internal */ export declare function isFrameServerInjected(frameData: ArrayBuffer, trailerBytes: Uint8Array): boolean; export {}; //# sourceMappingURL=FrameCryptor.d.ts.map