1.6. The Auditor RESTful JSON API

The API specified here follows the general conventions for all details not specified in the individual requests. The glossary defines all specific terms used in this section.

1.6.1. Obtaining Auditor Version

This API is used by merchants to obtain a list of all exchanges audited by this auditor. This may be required for the merchant to perform the required know-your-customer (KYC) registration before issuing contracts.

GET /config

Get the protocol version and some meta data about the auditor.

Response:

200 OK:

The auditor responds with an AuditorVersion object. This request should virtually always be successful.

Details:

interface AuditorVersion {
  // libtool-style representation of the Taler protocol version, see
  // https://www.gnu.org/software/libtool/manual/html_node/Versioning.html#Versioning
  // The format is "current:revision:age".  Note that the auditor
  // protocol is versioned independently of the exchange's protocol.
  version: string;

  // Return which currency this auditor is auditing for.
  currency: string;

  // EdDSA master public key of the auditor.
  auditor_public_key: EddsaPublicKey;
}

Note

This API is still experimental (and is not yet implemented at the time of this writing).

1.6.2. Obtaining Exchange List

This API is used by merchants to obtain a list of all exchanges audited by this auditor. This may be required for the merchant to perform the required know-your-customer (KYC) registration before issuing contracts.

GET /exchanges

Get a list of all exchanges audited by the auditor.

Response:

200 OK:

The auditor responds with a ExchangeList object. This request should virtually always be successful.

Details:

interface ExchangeList {
  // Exchanges audited by this auditor.
  exchanges: ExchangeEntry[];
}
interface ExchangeEntry {

  // Master public key of the exchange.
  master_pub: EddsaPublicKey;

  // Base URL of the exchange.
  exchange_url: string;
}

Note

This API is still experimental (and is not yet implemented at the time of this writing). A key open question is whether the auditor should sign the information. We might also want to support more delta downloads in the future.

1.6.3. Submitting deposit confirmations

Merchants should probabilistically submit some of the deposit confirmations they receive from the exchange to auditors to ensure that the exchange does not lie about recording deposit confirmations with the exchange. Participating in this scheme ensures that in case an exchange runs into financial trouble to pay its obligations, the merchants that did participate in detecting the bad behavior can be paid out first.

PUT /deposit-confirmation

Submits a DepositConfirmation to the exchange. Should succeed unless the signature provided is invalid or the exchange is not audited by this auditor.

Response:

200 Ok:

The auditor responds with a DepositAudited object. This request should virtually always be successful.

403 Forbidden:

The signature on the deposit confirmation is invalid.

410 Gone:

The public key used to sign the deposit confirmation was revoked.

Details:

interface DepositAudited {
  // TODO: maybe change to 204 No content instead?
}
interface DepositConfirmation {

  // Hash over the contract for which this deposit is made.
  h_contract_terms: HashCode;

  // Hash over the extensions.
  h_extensions: HashCode;

  // Hash over the wiring information of the merchant.
  h_wire: HashCode;

  // Time when the deposit confirmation confirmation was generated.
  timestamp: Timestamp;

  // How much time does the merchant have to issue a refund
  // request?  Zero if refunds are not allowed.
  refund_deadline: Timestamp;

  // By what time does the exchange have to wire the funds?
  wire_deadline: Timestamp;

  // Amount to be deposited, excluding fee.  Calculated from the
  // amount with fee and the fee from the deposit request.
  amount_without_fee: Amount;

  // Array of public keys of the deposited coins.
  coin_pubs: EddsaPublicKey[];

  // Array of deposit signatures of the deposited coins.
  // Must have the same length as coin_pubs.
  coin_sigs: EddsaSignature[];

  // The Merchant's public key.  Allows the merchant to later refund
  // the transaction or to inquire about the wire transfer identifier.
  merchant_pub: EddsaPublicKey;

  // Signature from the exchange of type
  // TALER_SIGNATURE_EXCHANGE_CONFIRM_DEPOSIT.
  exchange_sig: EddsaSignature;

  // Public signing key from the exchange matching exchange_sig.
  exchange_pub: EddsaPublicKey;

  // Master public key of the exchange corresponding to master_sig.
  // Identifies the exchange this is about.
  master_pub: EddsaPublicKey;

  // When does the validity of the exchange_pub end?
  ep_start: Timestamp;

  // When will the exchange stop using the signing key?
  ep_expire: Timestamp;

  // When does the validity of the exchange_pub end?
  ep_end: Timestamp;

  // Exchange master signature over exchange_sig.
  master_sig: EddsaSignature;
}

Note

This API is still experimental (and is not yet implemented at the time of this writing). A key open question is whether the auditor should sign the response information.

1.6.4. Complaints

This API is used by the wallet or merchants to submit proof of misbehavior of an exchange to the auditor.

Note

To be designed and implemented.

PUT /complain

Complain about misbehavior to the auditor.