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|
/*
This file is part of TALER
Copyright (C) 2014, 2015, 2016 GNUnet e.V.
TALER is free software; you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation; either version 3, or (at your option) any later version.
TALER is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
TALER; see the file COPYING. If not, If not, see <http://www.gnu.org/licenses/>
*/
/**
* @file taler_signatures.h
* @brief message formats and signature constants used to define
* the binary formats of signatures in Taler
* @author Florian Dold
* @author Benedikt Mueller
*
* This file should define the constants and C structs that one needs
* to know to implement Taler clients (wallets or merchants or
* auditor) that need to produce or verify Taler signatures.
*/
#ifndef TALER_SIGNATURES_H
#define TALER_SIGNATURES_H
#if HAVE_GNUNET_GNUNET_UTIL_LIB_H
#include <gnunet/gnunet_util_lib.h>
#elif HAVE_GNUNET_GNUNET_UTIL_TALER_WALLET_LIB_H
#include <gnunet/gnunet_util_taler_wallet_lib.h>
#endif
#include "taler_amount_lib.h"
#include "taler_crypto_lib.h"
/**
* Cut-and-choose size for refreshing. Client looses the gamble (of
* unaccountable transfers) with probability 1/TALER_CNC_KAPPA. Refresh cost
* increases linearly with TALER_CNC_KAPPA, and 3 is sufficient up to a
* income/sales tax of 66% of total transaction value. As there is
* no good reason to change this security parameter, we declare it
* fixed and part of the protocol.
*/
#define TALER_CNC_KAPPA 3
/**
* After what time do idle reserves "expire"? We might want to make
* this a configuration option (eventually).
*/
#define TALER_IDLE_RESERVE_EXPIRATION_TIME GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_YEARS, 5)
/*********************************************/
/* Exchange offline signatures (with master key) */
/*********************************************/
/**
* Purpose for signing public keys signed by the exchange master key.
*/
#define TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY 1024
/**
* Purpose for denomination keys signed by the exchange master key.
*/
#define TALER_SIGNATURE_MASTER_DENOMINATION_KEY_VALIDITY 1025
/**
* Signature where the Exchange confirms its SEPA details in
* the /wire response.
*/
#define TALER_SIGNATURE_MASTER_SEPA_DETAILS 1026
/**
* Signature where the Exchange confirms its TEST details in
* the /wire response.
*/
#define TALER_SIGNATURE_MASTER_TEST_DETAILS 1027
/*********************************************/
/* Exchange online signatures (with signing key) */
/*********************************************/
/**
* Purpose for the state of a reserve, signed by the exchange's signing
* key.
*/
#define TALER_SIGNATURE_EXCHANGE_RESERVE_STATUS 1032
/**
* Signature where the Exchange confirms a deposit request.
*/
#define TALER_SIGNATURE_EXCHANGE_CONFIRM_DEPOSIT 1033
/**
* Signature where the exchange (current signing key) confirms the
* no-reveal index for cut-and-choose and the validity of the melted
* coins.
*/
#define TALER_SIGNATURE_EXCHANGE_CONFIRM_MELT 1034
/**
* Signature where the Exchange confirms the full /keys response set.
*/
#define TALER_SIGNATURE_EXCHANGE_KEY_SET 1035
/**
* Signature where the Exchange confirms the /deposit/wtid response.
*/
#define TALER_SIGNATURE_EXCHANGE_CONFIRM_WIRE 1036
/**
* Signature where the Exchange confirms the /wire/deposit response.
*/
#define TALER_SIGNATURE_EXCHANGE_CONFIRM_WIRE_DEPOSIT 1037
/*********************/
/* Wallet signatures */
/*********************/
/**
* Signature where the auditor confirms that he is
* aware of certain denomination keys from the exchange.
*/
#define TALER_SIGNATURE_AUDITOR_EXCHANGE_KEYS 1064
/***********************/
/* Merchant signatures */
/***********************/
/**
* Signature where the merchant confirms a contract (to the customer).
*/
#define TALER_SIGNATURE_MERCHANT_CONTRACT 1101
/**
* Signature where the merchant confirms a refund (of a coin).
*/
#define TALER_SIGNATURE_MERCHANT_REFUND 1102
/**
* Signature where the merchant confirms that he needs the wire
* transfer identifier for a deposit operation.
*/
#define TALER_SIGNATURE_MERCHANT_DEPOSIT_WTID 1103
/*********************/
/* Wallet signatures */
/*********************/
/**
* Signature where the reserve key confirms a withdraw request.
*/
#define TALER_SIGNATURE_WALLET_RESERVE_WITHDRAW 1200
/**
* Signature made by the wallet of a user to confirm a deposit of a coin.
*/
#define TALER_SIGNATURE_WALLET_COIN_DEPOSIT 1201
/**
* Signature using a coin key confirming the melting of a coin.
*/
#define TALER_SIGNATURE_WALLET_COIN_MELT 1202
/*******************/
/* Test signatures */
/*******************/
/**
* EdDSA test signature.
*/
#define TALER_SIGNATURE_CLIENT_TEST_EDDSA 1302
/**
* EdDSA test signature.
*/
#define TALER_SIGNATURE_EXCHANGE_TEST_EDDSA 1303
GNUNET_NETWORK_STRUCT_BEGIN
/**
* @brief Format used for to generate the signature on a request to withdraw
* coins from a reserve.
*/
struct TALER_WithdrawRequestPS
{
/**
* Purpose must be #TALER_SIGNATURE_WALLET_RESERVE_WITHDRAW.
* Used with an EdDSA signature of a `struct TALER_ReservePublicKeyP`.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Reserve public key (which reserve to withdraw from). This is
* the public key which must match the signature.
*/
struct TALER_ReservePublicKeyP reserve_pub;
/**
* Value of the coin being exchangeed (matching the denomination key)
* plus the transaction fee. We include this in what is being
* signed so that we can verify a reserve's remaining total balance
* without needing to access the respective denomination key
* information each time.
*/
struct TALER_AmountNBO amount_with_fee;
/**
* Withdrawl fee charged by the exchange. This must match the Exchange's
* denomination key's withdrawl fee. If the client puts in an
* invalid withdrawl fee (too high or too low) that does not match
* the Exchange's denomination key, the withdraw operation is invalid
* and will be rejected by the exchange. The @e amount_with_fee minus
* the @e withdraw_fee is must match the value of the generated
* coin. We include this in what is being signed so that we can
* verify a exchange's accounting without needing to access the
* respective denomination key information each time.
*/
struct TALER_AmountNBO withdraw_fee;
/**
* Hash of the denomination public key for the coin that is withdrawn.
*/
struct GNUNET_HashCode h_denomination_pub GNUNET_PACKED;
/**
* Hash of the (blinded) message to be signed by the Exchange.
*/
struct GNUNET_HashCode h_coin_envelope GNUNET_PACKED;
};
/**
* @brief Format used to generate the signature on a request to deposit
* a coin into the account of a merchant.
*/
struct TALER_DepositRequestPS
{
/**
* Purpose must be #TALER_SIGNATURE_WALLET_COIN_DEPOSIT.
* Used for an EdDSA signature with the `struct TALER_CoinSpendPublicKeyP`.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Hash over the contract for which this deposit is made.
*/
struct GNUNET_HashCode h_contract GNUNET_PACKED;
/**
* Hash over the wiring information of the merchant.
*/
struct GNUNET_HashCode h_wire GNUNET_PACKED;
/**
* Time when this request was generated. Used, for example, to
* assess when (roughly) the income was achieved for tax purposes.
* Note that the Exchange will only check that the timestamp is not "too
* far" into the future (i.e. several days). The fact that the
* timestamp falls within the validity period of the coin's
* denomination key is irrelevant for the validity of the deposit
* request, as obviously the customer and merchant could conspire to
* set any timestamp. Also, the Exchange must accept very old deposit
* requests, as the merchant might have been unable to transmit the
* deposit request in a timely fashion (so back-dating is not
* prevented).
*/
struct GNUNET_TIME_AbsoluteNBO timestamp;
/**
* How much time does the merchant have to issue a refund request?
* Zero if refunds are not allowed. After this time, the coin
* cannot be refunded.
*/
struct GNUNET_TIME_AbsoluteNBO refund_deadline;
/**
* Merchant-generated transaction ID to detect duplicate
* transactions. The merchant must communicate a merchant-unique ID
* to the customer for each transaction. Note that different coins
* that are part of the same transaction can use the same
* transaction ID. The transaction ID is useful for later disputes,
* and the merchant's contract offer (@e h_contract) with the
* customer should include the offer's term and transaction ID
* signed with a key from the merchant.
*/
uint64_t transaction_id GNUNET_PACKED;
/**
* Amount to be deposited, including deposit fee charged by the
* exchange. This is the total amount that the coin's value at the exchange
* will be reduced by.
*/
struct TALER_AmountNBO amount_with_fee;
/**
* Depositing fee charged by the exchange. This must match the Exchange's
* denomination key's depositing fee. If the client puts in an
* invalid deposit fee (too high or too low) that does not match the
* Exchange's denomination key, the deposit operation is invalid and
* will be rejected by the exchange. The @e amount_with_fee minus the
* @e deposit_fee is the amount that will be transferred to the
* account identified by @e h_wire.
*/
struct TALER_AmountNBO deposit_fee;
/**
* The Merchant's public key. Allows the merchant to later refund
* the transaction or to inquire about the wire transfer identifier.
*/
struct TALER_MerchantPublicKeyP merchant;
/**
* The coin's public key. This is the value that must have been
* signed (blindly) by the Exchange. The deposit request is to be
* signed by the corresponding private key (using EdDSA).
*/
struct TALER_CoinSpendPublicKeyP coin_pub;
};
/**
* @brief Format used to generate the signature on a confirmation
* from the exchange that a deposit request succeeded.
*/
struct TALER_DepositConfirmationPS
{
/**
* Purpose must be #TALER_SIGNATURE_EXCHANGE_CONFIRM_DEPOSIT. Signed
* by a `struct TALER_ExchangePublicKeyP` using EdDSA.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Hash over the contract for which this deposit is made.
*/
struct GNUNET_HashCode h_contract GNUNET_PACKED;
/**
* Hash over the wiring information of the merchant.
*/
struct GNUNET_HashCode h_wire GNUNET_PACKED;
/**
* Merchant-generated transaction ID to detect duplicate
* transactions.
*/
uint64_t transaction_id GNUNET_PACKED;
/**
* Time when this confirmation was generated.
*/
struct GNUNET_TIME_AbsoluteNBO timestamp;
/**
* How much time does the @e merchant have to issue a refund
* request? Zero if refunds are not allowed. After this time, the
* coin cannot be refunded. Note that the wire transfer will not be
* performed by the exchange until the refund deadline. This value
* is taken from the original deposit request.
*/
struct GNUNET_TIME_AbsoluteNBO refund_deadline;
/**
* Amount to be deposited, excluding fee. Calculated from the
* amount with fee and the fee from the deposit request.
*/
struct TALER_AmountNBO amount_without_fee;
/**
* The coin's public key. This is the value that must have been
* signed (blindly) by the Exchange. The deposit request is to be
* signed by the corresponding private key (using EdDSA).
*/
struct TALER_CoinSpendPublicKeyP coin_pub;
/**
* The Merchant's public key. Allows the merchant to later refund
* the transaction or to inquire about the wire transfer identifier.
*/
struct TALER_MerchantPublicKeyP merchant;
};
/**
* @brief Format used to generate the signature on a request to refund
* a coin into the account of the customer.
*/
struct TALER_RefundRequestPS
{
/**
* Purpose must be #TALER_SIGNATURE_MERCHANT_REFUND.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Hash over the contract which is being refunded.
*/
struct GNUNET_HashCode h_contract GNUNET_PACKED;
/**
* Merchant-generated transaction ID of the orginal transaction.
*/
uint64_t transaction_id GNUNET_PACKED;
/**
* The coin's public key. This is the value that must have been
* signed (blindly) by the Exchange.
*/
struct TALER_CoinSpendPublicKeyP coin_pub;
/**
* The Merchant's public key. Allows the merchant to later refund
* the transaction or to inquire about the wire transfer identifier.
*/
struct TALER_MerchantPublicKeyP merchant;
/**
* Merchant-generated transaction ID for the refund.
*/
uint64_t rtransaction_id GNUNET_PACKED;
/**
* Amount to be refunded, including refund fee charged by the
* exchange to the customer.
*/
struct TALER_AmountNBO refund_amount;
/**
* Refund fee charged by the exchange. This must match the
* Exchange's denomination key's refund fee. If the client puts in
* an invalid refund fee (too high or too low) that does not match
* the Exchange's denomination key, the refund operation is invalid
* and will be rejected by the exchange. The @e amount_with_fee
* minus the @e refund_fee is the amount that will be credited to
* the original coin.
*/
struct TALER_AmountNBO refund_fee;
};
/**
* @brief Message signed by a coin to indicate that the coin should be
* melted.
*/
struct TALER_RefreshMeltCoinAffirmationPS
{
/**
* Purpose is #TALER_SIGNATURE_WALLET_COIN_MELT.
* Used for an EdDSA signature with the `struct TALER_CoinSpendPublicKeyP`.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Which melting session should the coin become a part of.
*/
struct GNUNET_HashCode session_hash GNUNET_PACKED;
/**
* How much of the value of the coin should be melted? This amount
* includes the fees, so the final amount contributed to the melt is
* this value minus the fee for melting the coin. We include the
* fee in what is being signed so that we can verify a reserve's
* remaining total balance without needing to access the respective
* denomination key information each time.
*/
struct TALER_AmountNBO amount_with_fee;
/**
* Melting fee charged by the exchange. This must match the Exchange's
* denomination key's melting fee. If the client puts in an invalid
* melting fee (too high or too low) that does not match the Exchange's
* denomination key, the melting operation is invalid and will be
* rejected by the exchange. The @e amount_with_fee minus the @e
* melt_fee is the amount that will be credited to the melting
* session.
*/
struct TALER_AmountNBO melt_fee;
/**
* The coin's public key. This is the value that must have been
* signed (blindly) by the Exchange. The deposit request is to be
* signed by the corresponding private key (using EdDSA).
*/
struct TALER_CoinSpendPublicKeyP coin_pub;
};
/**
* @brief Format of the block signed by the Exchange in response to a successful
* "/refresh/melt" request. Hereby the exchange affirms that all of the
* coins were successfully melted. This also commits the exchange to a
* particular index to not be revealed during the refresh.
*/
struct TALER_RefreshMeltConfirmationPS
{
/**
* Purpose is #TALER_SIGNATURE_EXCHANGE_CONFIRM_MELT. Signed
* by a `struct TALER_ExchangePublicKeyP` using EdDSA.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Hash of the refresh session.
*/
struct GNUNET_HashCode session_hash GNUNET_PACKED;
/**
* Index that the client will not have to reveal, in NBO.
* Must be smaller than #TALER_CNC_KAPPA.
*/
uint16_t noreveal_index GNUNET_PACKED;
/**
* Zero.
*/
uint16_t reserved GNUNET_PACKED;
};
/**
* @brief Information about a signing key of the exchange. Signing keys are used
* to sign exchange messages other than coins, i.e. to confirm that a
* deposit was successful or that a refresh was accepted.
*/
struct TALER_ExchangeSigningKeyValidityPS
{
/**
* Signature over the signing key (by the master key of the exchange).
*
* FIXME: should be moved outside of the "PS" struct, this is ugly.
* (and makes this struct different from all of the others)
*/
struct TALER_MasterSignatureP signature;
/**
* Purpose is #TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Master public key of the exchange corresponding to @e signature.
* This is the long-term offline master key of the exchange.
*/
struct TALER_MasterPublicKeyP master_public_key;
/**
* When does this signing key begin to be valid?
*/
struct GNUNET_TIME_AbsoluteNBO start;
/**
* When does this signing key expire? Note: This is currently when
* the Exchange will definitively stop using it. Signatures made with
* the key remain valid until @e end. When checking validity periods,
* clients should allow for some overlap between keys and tolerate
* the use of either key during the overlap time (due to the
* possibility of clock skew).
*/
struct GNUNET_TIME_AbsoluteNBO expire;
/**
* When do signatures with this signing key become invalid? After
* this point, these signatures cannot be used in (legal) disputes
* anymore, as the Exchange is then allowed to destroy its side of the
* evidence. @e end is expected to be significantly larger than @e
* expire (by a year or more).
*/
struct GNUNET_TIME_AbsoluteNBO end;
/**
* The public online signing key that the exchange will use
* between @e start and @e expire.
*/
struct TALER_ExchangePublicKeyP signkey_pub;
};
/**
* @brief Signature made by the exchange over the full set of keys, used
* to detect cheating exchanges that give out different sets to
* different users.
*/
struct TALER_ExchangeKeySetPS
{
/**
* Purpose is #TALER_SIGNATURE_EXCHANGE_KEY_SET. Signed
* by a `struct TALER_ExchangePublicKeyP` using EdDSA.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Time of the key set issue.
*/
struct GNUNET_TIME_AbsoluteNBO list_issue_date;
/**
* Hash over the various denomination signing keys returned.
*/
struct GNUNET_HashCode hc GNUNET_PACKED;
};
/**
* @brief Information about a denomination key. Denomination keys
* are used to sign coins of a certain value into existence.
*/
struct TALER_DenominationKeyValidityPS
{
/**
* Purpose is #TALER_SIGNATURE_MASTER_DENOMINATION_KEY_VALIDITY.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* The long-term offline master key of the exchange that was
* used to create @e signature.
*/
struct TALER_MasterPublicKeyP master;
/**
* Start time of the validity period for this key.
*/
struct GNUNET_TIME_AbsoluteNBO start;
/**
* The exchange will sign fresh coins between @e start and this time.
* @e expire_withdraw will be somewhat larger than @e start to
* ensure a sufficiently large anonymity set, while also allowing
* the Exchange to limit the financial damage in case of a key being
* compromised. Thus, exchanges with low volume are expected to have a
* longer withdraw period (@e expire_withdraw - @e start) than exchanges
* with high transaction volume. The period may also differ between
* types of coins. A exchange may also have a few denomination keys
* with the same value with overlapping validity periods, to address
* issues such as clock skew.
*/
struct GNUNET_TIME_AbsoluteNBO expire_withdraw;
/**
* Coins signed with the denomination key must be spent or refreshed
* between @e start and this expiration time. After this time, the
* exchange will refuse transactions involving this key as it will
* "drop" the table with double-spending information (shortly after)
* this time. Note that wallets should refresh coins significantly
* before this time to be on the safe side. @e expire_deposit must be
* significantly larger than @e expire_withdraw (by months or even
* years).
*/
struct GNUNET_TIME_AbsoluteNBO expire_deposit;
/**
* When do signatures with this denomination key become invalid?
* After this point, these signatures cannot be used in (legal)
* disputes anymore, as the Exchange is then allowed to destroy its side
* of the evidence. @e expire_legal is expected to be significantly
* larger than @e expire_deposit (by a year or more).
*/
struct GNUNET_TIME_AbsoluteNBO expire_legal;
/**
* The value of the coins signed with this denomination key.
*/
struct TALER_AmountNBO value;
/**
* The fee the exchange charges when a coin of this type is withdrawn.
* (can be zero).
*/
struct TALER_AmountNBO fee_withdraw;
/**
* The fee the exchange charges when a coin of this type is deposited.
* (can be zero).
*/
struct TALER_AmountNBO fee_deposit;
/**
* The fee the exchange charges when a coin of this type is refreshed.
* (can be zero).
*/
struct TALER_AmountNBO fee_refresh;
/**
* The fee the exchange charges when a coin of this type is refunded.
* (can be zero). Note that refund fees are charged to the customer;
* if a refund is given, the deposit fee is also refunded.
*/
struct TALER_AmountNBO fee_refund;
/**
* Hash code of the denomination public key. (Used to avoid having
* the variable-size RSA key in this struct.)
*/
struct GNUNET_HashCode denom_hash GNUNET_PACKED;
};
/**
* @brief Information signed by an auditor affirming
* the master public key and the denomination keys
* of a exchange.
*/
struct TALER_ExchangeKeyValidityPS
{
/**
* Purpose is #TALER_SIGNATURE_AUDITOR_EXCHANGE_KEYS.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Hash of the auditor's URL.
*/
struct GNUNET_HashCode auditor_url_hash;
/**
* The long-term offline master key of the exchange, affirmed by the
* auditor. Hashed string, including 0-terminator.
*/
struct TALER_MasterPublicKeyP master;
/**
* Start time of the validity period for this key.
*/
struct GNUNET_TIME_AbsoluteNBO start;
/**
* The exchange will sign fresh coins between @e start and this time.
* @e expire_withdraw will be somewhat larger than @e start to
* ensure a sufficiently large anonymity set, while also allowing
* the Exchange to limit the financial damage in case of a key being
* compromised. Thus, exchanges with low volume are expected to have a
* longer withdraw period (@e expire_withdraw - @e start) than exchanges
* with high transaction volume. The period may also differ between
* types of coins. A exchange may also have a few denomination keys
* with the same value with overlapping validity periods, to address
* issues such as clock skew.
*/
struct GNUNET_TIME_AbsoluteNBO expire_withdraw;
/**
* Coins signed with the denomination key must be spent or refreshed
* between @e start and this expiration time. After this time, the
* exchange will refuse transactions involving this key as it will
* "drop" the table with double-spending information (shortly after)
* this time. Note that wallets should refresh coins significantly
* before this time to be on the safe side. @e expire_deposit must be
* significantly larger than @e expire_withdraw (by months or even
* years).
*/
struct GNUNET_TIME_AbsoluteNBO expire_deposit;
/**
* When do signatures with this denomination key become invalid?
* After this point, these signatures cannot be used in (legal)
* disputes anymore, as the Exchange is then allowed to destroy its side
* of the evidence. @e expire_legal is expected to be significantly
* larger than @e expire_deposit (by a year or more).
*/
struct GNUNET_TIME_AbsoluteNBO expire_legal;
/**
* The value of the coins signed with this denomination key.
*/
struct TALER_AmountNBO value;
/**
* The fee the exchange charges when a coin of this type is withdrawn.
* (can be zero).
*/
struct TALER_AmountNBO fee_withdraw;
/**
* The fee the exchange charges when a coin of this type is deposited.
* (can be zero).
*/
struct TALER_AmountNBO fee_deposit;
/**
* The fee the exchange charges when a coin of this type is refreshed.
* (can be zero).
*/
struct TALER_AmountNBO fee_refresh;
/**
* The fee the exchange charges when a coin of this type is refreshed.
* (can be zero).
*/
struct TALER_AmountNBO fee_refund;
/**
* Hash code of the denomination public key. (Used to avoid having
* the variable-size RSA key in this struct.)
*/
struct GNUNET_HashCode denom_hash GNUNET_PACKED;
};
/**
* @brief For each (old) coin being melted, we have a `struct
* RefreshCommitLinkP` that allows the user to find the shared secret
* to decrypt the respective refresh links for the new coins in the
* `struct TALER_EXCHANGEDB_RefreshCommitCoin`.
*
* Part of the construction of the refresh session's hash and
* thus of what is signed there.
*/
struct TALER_RefreshCommitLinkP
{
/**
* Transfer public key, used to decrypt the @e shared_secret_enc
* in combintation with the corresponding private key of the
* coin.
*/
struct TALER_TransferPublicKeyP transfer_pub;
/**
* Encrypted shared secret to decrypt the link.
*/
struct TALER_EncryptedLinkSecretP shared_secret_enc;
};
/**
* @brief Information signed by the exchange's master
* key affirming the SEPA details for the exchange.
*/
struct TALER_MasterWireDetailsPS
{
/**
* Purpose is #TALER_SIGNATURE_MASTER_SEPA_DETAILS or
* #TALER_SIGNATURE_MASTER_TEST_DETAILS.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Hash over the account holder's name, IBAN and BIC
* code (all as 0-terminated strings).
*/
struct GNUNET_HashCode h_sepa_details GNUNET_PACKED;
};
/**
* @brief Format used to generate the signature on a request to obtain
* the wire transfer identifier associated with a deposit.
*/
struct TALER_DepositTrackPS
{
/**
* Purpose must be #TALER_SIGNATURE_MERCHANT_DEPOSIT_WTID.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Hash over the contract for which this deposit is made.
*/
struct GNUNET_HashCode h_contract GNUNET_PACKED;
/**
* Hash over the wiring information of the merchant.
*/
struct GNUNET_HashCode h_wire GNUNET_PACKED;
/**
* Merchant-generated transaction ID to detect duplicate
* transactions. The merchant must communicate a merchant-unique ID
* to the customer for each transaction. Note that different coins
* that are part of the same transaction can use the same
* transaction ID. The transaction ID is useful for later disputes,
* and the merchant's contract offer (@e h_contract) with the
* customer should include the offer's term and transaction ID
* signed with a key from the merchant.
*/
uint64_t transaction_id GNUNET_PACKED;
/**
* The Merchant's public key. The deposit inquiry request is to be
* signed by the corresponding private key (using EdDSA).
*/
struct TALER_MerchantPublicKeyP merchant;
/**
* The coin's public key. This is the value that must have been
* signed (blindly) by the Exchange.
*/
struct TALER_CoinSpendPublicKeyP coin_pub;
};
/**
* @brief Format internally used for packing the detailed information
* to generate the signature for /wire/deposits signatures.
*/
struct TALER_WireDepositDetailP
{
/**
* Hash of the contract
*/
struct GNUNET_HashCode h_contract;
/**
* Merchant's transaction ID in NBO.
*/
uint64_t transaction_id GNUNET_PACKED;
/**
* Coin's public key.
*/
struct TALER_CoinSpendPublicKeyP coin_pub;
/**
* Total value of the coin.
*/
struct TALER_AmountNBO deposit_value;
/**
* Fees charged by the exchange for the deposit.
*/
struct TALER_AmountNBO deposit_fee;
};
/**
* @brief Format used to generate the signature for /wire/deposit
* replies.
*/
struct TALER_WireDepositDataPS
{
/**
* Purpose header for the signature over the contract with
* purpose #TALER_SIGNATURE_EXCHANGE_CONFIRM_WIRE_DEPOSIT.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Total amount that was transferred.
*/
struct TALER_AmountNBO total;
/**
* Public key of the merchant (for all aggregated transactions).
*/
struct TALER_MerchantPublicKeyP merchant_pub;
/**
* Hash of wire details of the merchant.
*/
struct GNUNET_HashCode h_wire;
/**
* Hash of the individual deposits that were aggregated,
* each in the format of a `struct TALER_WireDepositDetailP`.
*/
struct GNUNET_HashCode h_details;
};
/**
* The contract sent by the merchant to the wallet.
*/
struct TALER_ContractPS
{
/**
* Purpose header for the signature over the contract with
* purpose #TALER_SIGNATURE_MERCHANT_CONTRACT.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Merchant-generated transaction ID to detect duplicate
* transactions, in big endian. The merchant must communicate a
* merchant-unique ID to the customer for each transaction. Note
* that different coins that are part of the same transaction can
* use the same transaction ID. The transaction ID is useful for
* later disputes, and the merchant's contract offer (@e h_contract)
* with the customer should include the offer's term and transaction
* ID signed with a key from the merchant. This field must match
* the corresponding field in the JSON contract.
*/
uint64_t transaction_id GNUNET_PACKED;
/**
* The total amount to be paid to the merchant. Note that if deposit
* fees are higher than @e max_fee, the actual total must be higher
* to cover the additional fees. This field must match the
* corresponding field in the JSON contract.
*/
struct TALER_AmountNBO total_amount;
/**
* The maximum fee the merchant is willing to cover. This field
* must match the corresponding field in the JSON contract.
*/
struct TALER_AmountNBO max_fee;
/**
* Hash of the JSON contract in UTF-8 including 0-termination,
* using JSON_COMPACT | JSON_SORT_KEYS
*/
struct GNUNET_HashCode h_contract;
};
/**
* Details affirmed by the exchange about a wire transfer the exchange
* claims to have done with respect to a deposit operation.
*/
struct TALER_ConfirmWirePS
{
/**
* Purpose header for the signature over the contract with
* purpose #TALER_SIGNATURE_EXCHANGE_CONFIRM_WIRE.
*/
struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
/**
* Hash over the wiring information of the merchant.
*/
struct GNUNET_HashCode h_wire GNUNET_PACKED;
/**
* Hash over the contract for which this deposit is made.
*/
struct GNUNET_HashCode h_contract GNUNET_PACKED;
/**
* Raw value (binary encoding) of the wire transfer subject.
*/
struct TALER_WireTransferIdentifierRawP wtid;
/**
* The coin's public key. This is the value that must have been
* signed (blindly) by the Exchange.
*/
struct TALER_CoinSpendPublicKeyP coin_pub;
/**
* Merchant-generated transaction ID to detect duplicate
* transactions, in big endian. The merchant must communicate a
* merchant-unique ID to the customer for each transaction. Note
* that different coins that are part of the same transaction can
* use the same transaction ID. The transaction ID is useful for
* later disputes, and the merchant's contract offer (@e h_contract)
* with the customer should include the offer's term and transaction
* ID signed with a key from the merchant.
*/
uint64_t transaction_id GNUNET_PACKED;
/**
* When did the exchange execute this transfer? Note that the
* timestamp may not be exactly the same on the wire, i.e.
* because the wire has a different timezone or resolution.
*/
struct GNUNET_TIME_AbsoluteNBO execution_time;
/**
* The contribution of @e coin_pub to the total transfer volume.
* This is the value of the deposit minus the fee.
*/
struct TALER_AmountNBO coin_contribution;
};
GNUNET_NETWORK_STRUCT_END
#endif
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