Class X3DH

constructor

• new X3DH(
      identityKeyManager?: IdentityKeyManagerInterface,
      sessionKeyManager?: SessionKeyManagerInterface,
      encryptor?: SymmetricEncryptionInterface,
      kdf?: KeyDerivationFunction,
  ): X3DH

  Parameters

  • OptionalidentityKeyManager: IdentityKeyManagerInterface
  • OptionalsessionKeyManager: SessionKeyManagerInterface
  • Optionalencryptor: SymmetricEncryptionInterface
  • Optionalkdf: KeyDerivationFunction

  Returns X3DH

encryptor

identityKeyManager

kdf

sessionKeyManager

decryptNext

• decryptNext(
      sender: string,
      encrypted: string,
  ): Promise<string | Uint8Array<ArrayBufferLike>>

  Decrypt the next message received by the sender.

  Parameters

  • sender: string
  • encrypted: string

  Returns Promise<string | Uint8Array<ArrayBufferLike>>

encryptNext

• encryptNext(
      recipient: string,
      message: string | Uint8Array<ArrayBufferLike>,
  ): Promise<string>

  Encrypt the next message to send to the recipient.

  Parameters

  • recipient: string
  • message: string | Uint8Array<ArrayBufferLike>

  Returns Promise<string>

generateOneTimeKeys

• generateOneTimeKeys(
      signingKey: CryptoKey,
      numKeys?: number,
  ): Promise<SignedBundle>

  Generates and signs a bundle of one-time keys.

  Useful for pushing more OTKs to the server.

  Parameters

  • signingKey: CryptoKey
  • numKeys: number = 100

  Returns Promise<SignedBundle>

initRecv

• initRecv(req: InitSenderInfo): Promise<(string | Uint8Array<ArrayBufferLike>)[]>

  Initialize keys for receiving an initial message. Returns the initial plaintext message on success. Throws on failure.

  Parameters

  • req: InitSenderInfo

  Returns Promise<(string | Uint8Array<ArrayBufferLike>)[]>

initRecvGetSk

• initRecvGetSk(
      req: InitSenderInfo,
      _recipientIdentity: string,
      preKeySecret: CryptoKey,
  ): Promise<{ IK: CryptoKey; Sender: string; SK: any }>

  Get the shared key when receiving an initial message.

  Parameters

  • req: InitSenderInfo
  • _recipientIdentity: string
  • preKeySecret: CryptoKey

  Returns Promise<{ IK: CryptoKey; Sender: string; SK: any }>

initSend

• initSend(
      recipientIdentity: string,
      getServerResponse: InitClientFunction,
      message: string | Uint8Array<ArrayBufferLike>,
  ): Promise<InitSenderInfo>

  Initialize for sending.

  Parameters

  • recipientIdentity: string
  • getServerResponse: InitClientFunction
  • message: string | Uint8Array<ArrayBufferLike>

  Returns Promise<InitSenderInfo>

initSenderGetSK

• initSenderGetSK(
      res: InitServerInfo,
      _senderIdentity: string,
  ): Promise<RecipientInitWithSK>

  Get the shared key when sending an initial message.

  Parameters

  • res: InitServerInfo
  • _senderIdentity: string

    not needed for key operations, ust for context

  Returns Promise<RecipientInitWithSK>

setIdentityString

• setIdentityString(id: string): Promise<void>

  Sets the identity string for the current user.

  Parameters

  • id: string

  Returns Promise<void>

signPreKey

• signPreKey(signingKey: CryptoKey, preKey: CryptoKey): Promise<string>

  Sign a pre-key with the identity key. This is what should be used for signed pre-keys in X3DH.

  Parameters

  • signingKey: CryptoKey
  • preKey: CryptoKey

  Returns Promise<string>