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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 include/taler_exchangedb_plugin.h
+ * @brief Low-level (statement-level) database access for the exchange
+ * @author Florian Dold
+ * @author Christian Grothoff
+ */
+#ifndef TALER_EXCHANGEDB_PLUGIN_H
+#define TALER_EXCHANGEDB_PLUGIN_H
+
+#include <gnunet/gnunet_util_lib.h>
+#include "taler_exchangedb_lib.h"
+
+
+/**
+ * @brief Information we keep on bank transfer(s) that established a reserve.
+ */
+struct TALER_EXCHANGEDB_BankTransfer
+{
+
+ /**
+ * Public key of the reserve that was filled.
+ */
+ struct TALER_ReservePublicKeyP reserve_pub;
+
+ /**
+ * Amount that was transferred to the exchange.
+ */
+ struct TALER_Amount amount;
+
+ /**
+ * When did the exchange receive the incoming transaction?
+ * (This is the execution date of the exchange's database,
+ * the execution date of the bank should be in @e wire).
+ */
+ struct GNUNET_TIME_Absolute execution_date;
+
+ /**
+ * Detailed wire information about the transaction.
+ */
+ json_t *wire;
+
+};
+
+
+/**
+ * @brief A summary of a Reserve
+ */
+struct TALER_EXCHANGEDB_Reserve
+{
+ /**
+ * The reserve's public key. This uniquely identifies the reserve
+ */
+ struct TALER_ReservePublicKeyP pub;
+
+ /**
+ * The balance amount existing in the reserve
+ */
+ struct TALER_Amount balance;
+
+ /**
+ * The expiration date of this reserve
+ */
+ struct GNUNET_TIME_Absolute expiry;
+};
+
+
+/**
+ * @brief Information we keep for a withdrawn coin to reproduce
+ * the /withdraw operation if needed, and to have proof
+ * that a reserve was drained by this amount.
+ */
+struct TALER_EXCHANGEDB_CollectableBlindcoin
+{
+
+ /**
+ * Our signature over the (blinded) coin.
+ */
+ struct TALER_DenominationSignature sig;
+
+ /**
+ * Denomination key (which coin was generated).
+ */
+ struct TALER_DenominationPublicKey denom_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_Amount 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_Amount withdraw_fee;
+
+ /**
+ * Public key of the reserve that was drained.
+ */
+ struct TALER_ReservePublicKeyP reserve_pub;
+
+ /**
+ * Hash over the blinded message, needed to verify
+ * the @e reserve_sig.
+ */
+ struct GNUNET_HashCode h_coin_envelope;
+
+ /**
+ * Signature confirming the withdrawl, matching @e reserve_pub,
+ * @e denom_pub and @e h_coin_envelope.
+ */
+ struct TALER_ReserveSignatureP reserve_sig;
+};
+
+
+
+/**
+ * @brief Types of operations on a reserved.
+ */
+enum TALER_EXCHANGEDB_ReserveOperation
+{
+ /**
+ * Money was deposited into the reserve via a bank transfer.
+ */
+ TALER_EXCHANGEDB_RO_BANK_TO_EXCHANGE = 0,
+
+ /**
+ * A Coin was withdrawn from the reserve using /withdraw.
+ */
+ TALER_EXCHANGEDB_RO_WITHDRAW_COIN = 1
+};
+
+
+/**
+ * @brief Reserve history as a linked list. Lists all of the transactions
+ * associated with this reserve (such as the bank transfers that
+ * established the reserve and all /withdraw operations we have done
+ * since).
+ */
+struct TALER_EXCHANGEDB_ReserveHistory
+{
+
+ /**
+ * Next entry in the reserve history.
+ */
+ struct TALER_EXCHANGEDB_ReserveHistory *next;
+
+ /**
+ * Type of the event, determins @e details.
+ */
+ enum TALER_EXCHANGEDB_ReserveOperation type;
+
+ /**
+ * Details of the operation, depending on @e type.
+ */
+ union
+ {
+
+ /**
+ * Details about a bank transfer to the exchange.
+ */
+ struct TALER_EXCHANGEDB_BankTransfer *bank;
+
+ /**
+ * Details about a /withdraw operation.
+ */
+ struct TALER_EXCHANGEDB_CollectableBlindcoin *withdraw;
+
+ } details;
+
+};
+
+
+/**
+ * @brief Specification for a /deposit operation. The combination of
+ * the coin's public key, the merchant's public key and the
+ * transaction ID must be unique. While a coin can (theoretically) be
+ * deposited at the same merchant twice (with partial spending), the
+ * merchant must either use a different public key or a different
+ * transaction ID for the two transactions. The same coin must not
+ * be used twice at the same merchant for the same transaction
+ * (as determined by transaction ID). (Note: we might want to
+ * fix #3819 and include at least h_contract as well.)
+ */
+struct TALER_EXCHANGEDB_Deposit
+{
+ /**
+ * Information about the coin that is being deposited.
+ */
+ struct TALER_CoinPublicInfo coin;
+
+ /**
+ * ECDSA signature affirming that the customer intends
+ * this coin to be deposited at the merchant identified
+ * by @e h_wire in relation to the contract identified
+ * by @e h_contract.
+ */
+ struct TALER_CoinSpendSignatureP csig;
+
+ /**
+ * Public key of the merchant. Enables later identification
+ * of the merchant in case of a need to rollback transactions.
+ */
+ struct TALER_MerchantPublicKeyP merchant_pub;
+
+ /**
+ * Hash over the contract between merchant and customer
+ * (remains unknown to the Exchange).
+ */
+ struct GNUNET_HashCode h_contract;
+
+ /**
+ * Hash of the (canonical) representation of @e wire, used
+ * to check the signature on the request. Generated by
+ * the exchange from the detailed wire data provided by the
+ * merchant.
+ */
+ struct GNUNET_HashCode h_wire;
+
+ /**
+ * Detailed wire information for executing the transaction.
+ */
+ json_t *wire;
+
+ /**
+ * Merchant-generated transaction ID to detect duplicate
+ * transactions.
+ */
+ uint64_t transaction_id;
+
+ /**
+ * 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_Absolute 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_Absolute refund_deadline;
+
+ /**
+ * How much time does the merchant have to execute the wire transfer?
+ * This time is advisory for aggregating transactions, not a hard
+ * constraint (as the merchant can theoretically pick any time,
+ * including one in the past).
+ */
+ struct GNUNET_TIME_Absolute wire_deadline;
+
+ /**
+ * Fraction of the coin's remaining value to be deposited, including
+ * depositing fee (if any). The coin is identified by @e coin_pub.
+ */
+ struct TALER_Amount amount_with_fee;
+
+ /**
+ * Depositing fee.
+ */
+ struct TALER_Amount deposit_fee;
+
+};
+
+
+/**
+ * @brief Global information for a refreshing session. Includes
+ * dimensions of the operation, security parameters and
+ * client signatures from "/refresh/melt" and "/refresh/commit".
+ */
+struct TALER_EXCHANGEDB_RefreshSession
+{
+
+ /**
+ * Number of coins we are melting.
+ */
+ uint16_t num_oldcoins;
+
+ /**
+ * Number of new coins we are creating.
+ */
+ uint16_t num_newcoins;
+
+ /**
+ * Index (smaller #TALER_CNC_KAPPA) which the exchange has chosen to not
+ * have revealed during cut and choose.
+ */
+ uint16_t noreveal_index;
+
+};
+
+
+/**
+ * @brief Specification for coin in a /refresh/melt operation.
+ */
+struct TALER_EXCHANGEDB_RefreshMelt
+{
+ /**
+ * Information about the coin that is being melted.
+ */
+ struct TALER_CoinPublicInfo coin;
+
+ /**
+ * Signature over the melting operation.
+ */
+ struct TALER_CoinSpendSignatureP coin_sig;
+
+ /**
+ * Hash of the refresh session this coin is melted into.
+ */
+ struct GNUNET_HashCode session_hash;
+
+ /**
+ * How much value is being 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_Amount 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_Amount melt_fee;
+
+};
+
+
+/**
+ * @brief We have as many `struct TALER_EXCHANGEDB_RefreshCommitCoin` as there are new
+ * coins being created by the refresh (for each of the #TALER_CNC_KAPPA
+ * sets). These are the coins we ask the exchange to sign if the
+ * respective set is selected.
+ */
+struct TALER_EXCHANGEDB_RefreshCommitCoin
+{
+
+ /**
+ * Encrypted data allowing those able to decrypt it to derive
+ * the private keys of the new coins created by the refresh.
+ */
+ struct TALER_RefreshLinkEncrypted *refresh_link;
+
+ /**
+ * Blinded message to be signed (in envelope), with @e coin_env_size bytes.
+ */
+ char *coin_ev;
+
+ /**
+ * Number of bytes in @e coin_ev.
+ */
+ size_t coin_ev_size;
+
+};
+
+
+/**
+ * @brief Linked list of refresh information linked to a coin.
+ */
+struct TALER_EXCHANGEDB_LinkDataList
+{
+ /**
+ * Information is stored in a NULL-terminated linked list.
+ */
+ struct TALER_EXCHANGEDB_LinkDataList *next;
+
+ /**
+ * Link data, used to recover the private key of the coin
+ * by the owner of the old coin.
+ */
+ struct TALER_RefreshLinkEncrypted *link_data_enc;
+
+ /**
+ * Denomination public key, determines the value of the coin.
+ */
+ struct TALER_DenominationPublicKey denom_pub;
+
+ /**
+ * Signature over the blinded envelope.
+ */
+ struct TALER_DenominationSignature ev_sig;
+};
+
+
+/**
+ * @brief Enumeration to classify the different types of transactions
+ * that can be done with a coin.
+ */
+enum TALER_EXCHANGEDB_TransactionType
+{
+ /**
+ * /deposit operation.
+ */
+ TALER_EXCHANGEDB_TT_DEPOSIT = 0,
+
+ /**
+ * /refresh/melt operation.
+ */
+ TALER_EXCHANGEDB_TT_REFRESH_MELT = 1
+
+};
+
+
+/**
+ * @brief List of transactions we performed for a particular coin.
+ */
+struct TALER_EXCHANGEDB_TransactionList
+{
+
+ /**
+ * Next pointer in the NULL-terminated linked list.
+ */
+ struct TALER_EXCHANGEDB_TransactionList *next;
+
+ /**
+ * Type of the transaction, determines what is stored in @e details.
+ */
+ enum TALER_EXCHANGEDB_TransactionType type;
+
+ /**
+ * Details about the transaction, depending on @e type.
+ */
+ union
+ {
+
+ /**
+ * Details if transaction was a /deposit operation.
+ */
+ struct TALER_EXCHANGEDB_Deposit *deposit;
+
+ /**
+ * Details if transaction was a /refresh/melt operation.
+ */
+ struct TALER_EXCHANGEDB_RefreshMelt *melt;
+
+ } details;
+
+};
+
+
+/**
+ * @brief All of the information from a /refresh/melt commitment.
+ */
+struct TALER_EXCHANGEDB_MeltCommitment
+{
+
+ /**
+ * Number of coins we are melting.
+ */
+ uint16_t num_oldcoins;
+
+ /**
+ * Number of new coins we are creating.
+ */
+ uint16_t num_newcoins;
+
+ /**
+ * Array of @e num_oldcoins melt operation details.
+ */
+ struct TALER_EXCHANGEDB_RefreshMelt *melts;
+
+ /**
+ * Array of @e num_newcoins denomination keys
+ */
+ struct TALER_DenominationPublicKey *denom_pubs;
+
+ /**
+ * 2D-Array of #TALER_CNC_KAPPA and @e num_newcoins commitments.
+ */
+ struct TALER_EXCHANGEDB_RefreshCommitCoin *commit_coins[TALER_CNC_KAPPA];
+
+ /**
+ * 2D-Array of #TALER_CNC_KAPPA and @e new_oldcoins links.
+ */
+ struct TALER_RefreshCommitLinkP *commit_links[TALER_CNC_KAPPA];
+};
+
+
+/**
+ * @brief Handle for a database session (per-thread, for transactions).
+ */
+struct TALER_EXCHANGEDB_Session;
+
+
+/**
+ * Function called with details about deposits that
+ * have been made, with the goal of executing the
+ * corresponding wire transaction.
+ *
+ * @param cls closure
+ * @param rowid unique ID for the deposit in our DB, used for marking
+ * it as 'tiny' or 'done'
+ * @param merchant_pub public key of the merchant
+ * @param coin_pub public key of the coin
+ * @param amount_with_fee amount that was deposited including fee
+ * @param deposit_fee amount the exchange gets to keep as transaction fees
+ * @param transaction_id unique transaction ID chosen by the merchant
+ * @param h_contract hash of the contract between merchant and customer
+ * @param wire_deadline by which the merchant adviced that he would like the
+ * wire transfer to be executed
+ * @param wire wire details for the merchant, NULL from iterate_matching_deposits()
+ * @return #GNUNET_OK to continue to iterate, #GNUNET_SYSERR to stop
+ */
+typedef int
+(*TALER_EXCHANGEDB_DepositIterator)(void *cls,
+ unsigned long long rowid,
+ const struct TALER_MerchantPublicKeyP *merchant_pub,
+ const struct TALER_CoinSpendPublicKeyP *coin_pub,
+ const struct TALER_Amount *amount_with_fee,
+ const struct TALER_Amount *deposit_fee,
+ uint64_t transaction_id,
+ const struct GNUNET_HashCode *h_contract,
+ struct GNUNET_TIME_Absolute wire_deadline,
+ const json_t *wire);
+
+
+/**
+ * Function called with the session hashes and transfer secret
+ * information for a given coin.
+ *
+ * @param cls closure
+ * @param session_hash a session the coin was melted in
+ * @param transfer_pub public transfer key for the session
+ * @param shared_secret_enc set to shared secret for the session
+ */
+typedef void
+(*TALER_EXCHANGEDB_TransferDataCallback)(void *cls,
+ const struct GNUNET_HashCode *session_hash,
+ const struct TALER_TransferPublicKeyP *transfer_pub,
+ const struct TALER_EncryptedLinkSecretP *shared_secret_enc);
+
+
+/**
+ * Function called with the results of the lookup of the
+ * wire transfer identifier information. Only called if
+ * we are at least aware of the transaction existing.
+ *
+ * @param cls closure
+ * @param wtid wire transfer identifier, NULL
+ * if the transaction was not yet done
+ * @param coin_contribution how much did the coin we asked about
+ * contribute to the total transfer value? (deposit value including fee)
+ * @param coin_fee how much did the exchange charge for the deposit fee
+ * @param execution_time when was the transaction done, or
+ * when we expect it to be done (if @a wtid was NULL)
+ */
+typedef void
+(*TALER_EXCHANGEDB_DepositWtidCallback)(void *cls,
+ const struct TALER_WireTransferIdentifierRawP *wtid,
+ const struct TALER_Amount *coin_contribution,
+ const struct TALER_Amount *coin_fee,
+ struct GNUNET_TIME_Absolute execution_time);
+
+
+/**
+ * Function called with the results of the lookup of the
+ * transaction data associated with a wire transfer identifier.
+ *
+ * @param cls closure
+ * @param merchant_pub public key of the merchant (should be same for all callbacks with the same @e cls)
+ * @param h_wire hash of wire transfer details of the merchant (should be same for all callbacks with the same @e cls)
+ * @param h_contract which contract was this payment about
+ * @param transaction_id merchant's transaction ID for the payment
+ * @param coin_pub which public key was this payment about
+ * @param coin_value amount contributed by this coin in total (with fee)
+ * @param coin_fee applicable fee for this coin
+ */
+typedef void
+(*TALER_EXCHANGEDB_WireTransferDataCallback)(void *cls,
+ const struct TALER_MerchantPublicKeyP *merchant_pub,
+ const struct GNUNET_HashCode *h_wire,
+ const struct GNUNET_HashCode *h_contract,
+ uint64_t transaction_id,
+ const struct TALER_CoinSpendPublicKeyP *coin_pub,
+ const struct TALER_Amount *coin_value,
+ const struct TALER_Amount *coin_fee);
+
+
+/**
+ * Callback with data about a prepared transaction.
+ *
+ * @param cls closure
+ * @param rowid row identifier used to mark prepared transaction as done
+ * @param buf transaction data that was persisted, NULL on error
+ * @param buf_size number of bytes in @a buf, 0 on error
+ */
+typedef void
+(*TALER_EXCHANGEDB_WirePreparationCallback) (void *cls,
+ unsigned long long rowid,
+ const char *buf,
+ size_t buf_size);
+
+
+/**
+ * @brief The plugin API, returned from the plugin's "init" function.
+ * The argument given to "init" is simply a configuration handle.
+ */
+struct TALER_EXCHANGEDB_Plugin
+{
+
+ /**
+ * Closure for all callbacks.
+ */
+ void *cls;
+
+ /**
+ * Name of the library which generated this plugin. Set by the
+ * plugin loader.
+ */
+ char *library_name;
+
+ /**
+ * Get the thread-local database-handle.
+ * Connect to the db if the connection does not exist yet.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param temporary #GNUNET_YES to use a temporary schema; #GNUNET_NO to use the
+ * database default one
+ * @param the database connection, or NULL on error
+ */
+ struct TALER_EXCHANGEDB_Session *
+ (*get_session) (void *cls,
+ int temporary);
+
+
+ /**
+ * Drop the temporary taler schema. This is only useful for testcases.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
+ */
+ int
+ (*drop_temporary) (void *cls,
+ struct TALER_EXCHANGEDB_Session *db);
+
+
+ /**
+ * Create the necessary tables if they are not present
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param temporary should we use a temporary schema
+ * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
+ */
+ int
+ (*create_tables) (void *cls,
+ int temporary);
+
+
+ /**
+ * Start a transaction.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to use
+ * @return #GNUNET_OK on success
+ */
+ int
+ (*start) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session);
+
+
+ /**
+ * Commit a transaction.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to use
+ * @return #GNUNET_OK on success, #GNUNET_NO if the transaction
+ * can be retried, #GNUNET_SYSERR on hard failures
+ */
+ int
+ (*commit) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session);
+
+
+ /**
+ * Abort/rollback a transaction.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to use
+ */
+ void
+ (*rollback) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session);
+
+
+ /**
+ * Insert information about a denomination key and in particular
+ * the properties (value, fees, expiration times) the coins signed
+ * with this key have.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to use
+ * @param denom_pub the public key used for signing coins of this denomination
+ * @param issue issuing information with value, fees and other info about the coin
+ * @return #GNUNET_OK on success; #GNUNET_SYSERR on failure
+ */
+ int
+ (*insert_denomination_info) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_DenominationPublicKey *denom_pub,
+ const struct TALER_EXCHANGEDB_DenominationKeyInformationP *issue);
+
+
+ /**
+ * Fetch information about a denomination key.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to use
+ * @param denom_pub the public key used for signing coins of this denomination
+ * @param[out] issue set to issue information with value, fees and other info about the coin, can be NULL
+ * @return #GNUNET_OK on success; #GNUNET_NO if no record was found, #GNUNET_SYSERR on failure
+ */
+ int
+ (*get_denomination_info) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_DenominationPublicKey *denom_pub,
+ struct TALER_EXCHANGEDB_DenominationKeyInformationP *issue);
+
+
+ /**
+ * Get the summary of a reserve.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param db the database connection handle
+ * @param[in,out] reserve the reserve data. The public key of the reserve should be set
+ * in this structure; it is used to query the database. The balance
+ * and expiration are then filled accordingly.
+ * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
+ */
+ int
+ (*reserve_get) (void *cls,
+ struct TALER_EXCHANGEDB_Session *db,
+ struct TALER_EXCHANGEDB_Reserve *reserve);
+
+
+ /**
+ * Insert a incoming transaction into reserves. New reserves are
+ * also created through this function. Note that this API call
+ * starts (and stops) its own transaction scope (so the application
+ * must not do so).
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param db the database connection handle
+ * @param reserve_pub public key of the reserve
+ * @param balance the amount that has to be added to the reserve
+ * @param execution_time when was the amount added
+ * @param details bank transaction details justifying the increment,
+ * must be unique for each incoming transaction
+ * @return #GNUNET_OK upon success; #GNUNET_NO if the given
+ * @a details are already known for this @a reserve_pub,
+ * #GNUNET_SYSERR upon failures (DB error, incompatible currency)
+ */
+ int
+ (*reserves_in_insert) (void *cls,
+ struct TALER_EXCHANGEDB_Session *db,
+ const struct TALER_ReservePublicKeyP *reserve_pub,
+ const struct TALER_Amount *balance,
+ struct GNUNET_TIME_Absolute execution_time,
+ const json_t *details);
+
+
+ /**
+ * Locate the response for a /withdraw request under the
+ * key of the hash of the blinded message.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection to use
+ * @param h_blind hash of the blinded coin to be signed (will match
+ * `h_coin_envelope` in the @a collectable to be returned)
+ * @param collectable corresponding collectable coin (blind signature)
+ * if a coin is found
+ * @return #GNUNET_SYSERR on internal error
+ * #GNUNET_NO if the collectable was not found
+ * #GNUNET_YES on success
+ */
+ int
+ (*get_withdraw_info) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *h_blind,
+ struct TALER_EXCHANGEDB_CollectableBlindcoin *collectable);
+
+
+ /**
+ * Store collectable bit coin under the corresponding
+ * hash of the blinded message.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection to use
+ * @param collectable corresponding collectable coin (blind signature)
+ * if a coin is found
+ * @return #GNUNET_SYSERR on internal error
+ * #GNUNET_NO if the collectable was not found
+ * #GNUNET_YES on success
+ */
+ int
+ (*insert_withdraw_info) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_EXCHANGEDB_CollectableBlindcoin *collectable);
+
+
+ /**
+ * Get all of the transaction history associated with the specified
+ * reserve.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to use
+ * @param reserve_pub public key of the reserve
+ * @return known transaction history (NULL if reserve is unknown)
+ */
+ struct TALER_EXCHANGEDB_ReserveHistory *
+ (*get_reserve_history) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_ReservePublicKeyP *reserve_pub);
+
+
+ /**
+ * Free memory associated with the given reserve history.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param rh history to free.
+ */
+ void
+ (*free_reserve_history) (void *cls,
+ struct TALER_EXCHANGEDB_ReserveHistory *rh);
+
+
+ /**
+ * Check if we have the specified deposit already in the database.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param deposit deposit to search for
+ * @return #GNUNET_YES if we know this operation,
+ * #GNUNET_NO if this exact deposit is unknown to us,
+ * #GNUNET_SYSERR on DB error
+ */
+ int
+ (*have_deposit) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_EXCHANGEDB_Deposit *deposit);
+
+
+ /**
+ * Insert information about deposited coin into the database.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to the database
+ * @param deposit deposit information to store
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+ int
+ (*insert_deposit) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_EXCHANGEDB_Deposit *deposit);
+
+
+ /**
+ * Mark a deposit as tiny, thereby declaring that it cannot be
+ * executed by itself and should no longer be returned by
+ * @e iterate_ready_deposits()
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to the database
+ * @param deposit_rowid identifies the deposit row to modify
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+ int
+ (*mark_deposit_tiny) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ unsigned long long rowid);
+
+
+ /**
+ * Mark a deposit as done, thereby declaring that it cannot be
+ * executed at all anymore, and should no longer be returned by
+ * @e iterate_ready_deposits() or @e iterate_matching_deposits().
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to the database
+ * @param deposit_rowid identifies the deposit row to modify
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+ int
+ (*mark_deposit_done) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ unsigned long long rowid);
+
+
+ /**
+ * Obtain information about deposits that are ready to be executed.
+ * Such deposits must not be marked as "tiny" or "done", and the
+ * execution time must be in the past.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to the database
+ * @param deposit_cb function to call for ONE such deposit
+ * @param deposit_cb_cls closure for @a deposit_cb
+ * @return number of rows processed, 0 if none exist,
+ * #GNUNET_SYSERR on error
+ */
+ int
+ (*get_ready_deposit) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ TALER_EXCHANGEDB_DepositIterator deposit_cb,
+ void *deposit_cb_cls);
+
+
+ /**
+ * Obtain information about other pending deposits for the same
+ * destination. Those deposits must not already be "done".
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session connection to the database
+ * @param h_wire destination of the wire transfer
+ * @param merchant_pub public key of the merchant
+ * @param deposit_cb function to call for each deposit
+ * @param deposit_cb_cls closure for @a deposit_cb
+ * @param limit maximum number of matching deposits to return
+ * @return number of rows processed, 0 if none exist,
+ * #GNUNET_SYSERR on error
+ */
+ int
+ (*iterate_matching_deposits) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *h_wire,
+ const struct TALER_MerchantPublicKeyP *merchant_pub,
+ TALER_EXCHANGEDB_DepositIterator deposit_cb,
+ void *deposit_cb_cls,
+ uint32_t limit);
+
+
+ /**
+ * Lookup refresh session data under the given @a session_hash.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database handle to use
+ * @param session_hash hash over the melt to use for the lookup
+ * @param[out] refresh_session where to store the result
+ * @return #GNUNET_YES on success,
+ * #GNUNET_NO if not found,
+ * #GNUNET_SYSERR on DB failure
+ */
+ int
+ (*get_refresh_session) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ struct TALER_EXCHANGEDB_RefreshSession *refresh_session);
+
+
+ /**
+ * Store new refresh session data under the given @a session_hash.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database handle to use
+ * @param session_hash hash over the melt to use to locate the session
+ * @param refresh_session session data to store
+ * @return #GNUNET_YES on success,
+ * #GNUNET_SYSERR on DB failure
+ */
+ int
+ (*create_refresh_session) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ const struct TALER_EXCHANGEDB_RefreshSession *refresh_session);
+
+
+ /**
+ * Store the given /refresh/melt request in the database.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param oldcoin_index index of the coin to store
+ * @param melt coin melt operation details to store; includes
+ * the session hash of the melt
+ * @return #GNUNET_OK on success
+ * #GNUNET_SYSERR on internal error
+ */
+ int
+ (*insert_refresh_melt) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ uint16_t oldcoin_index,
+ const struct TALER_EXCHANGEDB_RefreshMelt *melt);
+
+
+ /**
+ * Get information about melted coin details from the database.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param session_hash hash to identify refresh session
+ * @param oldcoin_index index of the coin to retrieve
+ * @param melt melt data to fill in, can be NULL
+ * @return #GNUNET_OK on success
+ * #GNUNET_SYSERR on internal error
+ */
+ int
+ (*get_refresh_melt) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ uint16_t oldcoin_index,
+ struct TALER_EXCHANGEDB_RefreshMelt *melt);
+
+
+ /**
+ * Store in the database which coin(s) we want to create
+ * in a given refresh operation.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param session_hash hash to identify refresh session
+ * @param num_newcoins number of coins to generate, size of the @a denom_pubs array
+ * @param denom_pubs array denominations of the coins to create
+ * @return #GNUNET_OK on success
+ * #GNUNET_SYSERR on internal error
+ */
+ int
+ (*insert_refresh_order) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ uint16_t num_newcoins,
+ const struct TALER_DenominationPublicKey *denom_pubs);
+
+
+ /**
+ * Lookup in the database for the @a num_newcoins coins that we want to
+ * create in the given refresh operation.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param session_hash hash to identify refresh session
+ * @param num_newcoins size of the @a denom_pubs array
+ * @param[out] denom_pubs where to write @a num_newcoins denomination keys
+ * @return #GNUNET_OK on success
+ * #GNUNET_SYSERR on internal error
+ */
+ int
+ (*get_refresh_order) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ uint16_t num_newcoins,
+ struct TALER_DenominationPublicKey *denom_pubs);
+
+
+ /**
+ * Store information about the commitments of the given index @a i
+ * for the given refresh session in the database.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection to use
+ * @param session_hash hash to identify refresh session
+ * @param cnc_index cut and choose index (1st dimension), relating to #TALER_CNC_KAPPA
+ * @param num_newcoins coin index size of the @a commit_coins array
+ * @param commit_coin array of coin commitments to store
+ * @return #GNUNET_OK on success
+ * #GNUNET_SYSERR on error
+ */
+ int
+ (*insert_refresh_commit_coins) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ uint16_t cnc_index,
+ uint16_t num_newcoins,
+ const struct TALER_EXCHANGEDB_RefreshCommitCoin *commit_coins);
+
+
+ /**
+ * Obtain information about the commitment of the
+ * given coin of the given refresh session from the database.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection to use
+ * @param session_hash hash to identify refresh session
+ * @param cnc_index cut and choose set index (1st dimension)
+ * @param num_coins size of the @a commit_coins array
+ * @param[out] commit_coins array of coin commitments to return
+ * @return #GNUNET_OK on success
+ * #GNUNET_NO if not found
+ * #GNUNET_SYSERR on error
+ */
+ int
+ (*get_refresh_commit_coins) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ uint16_t cnc_index,
+ uint16_t num_coins,
+ struct TALER_EXCHANGEDB_RefreshCommitCoin *commit_coins);
+
+
+ /**
+ * Store the commitment to the given (encrypted) refresh link data
+ * for the given refresh session.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection to use
+ * @param session_hash hash to identify refresh session
+ * @param cnc_index cut and choose index (1st dimension), relating to #TALER_CNC_KAPPA
+ * @param num_links size of the @a commit_link array
+ * @param commit_links array of link information to store
+ * @return #GNUNET_SYSERR on internal error, #GNUNET_OK on success
+ */
+ int
+ (*insert_refresh_commit_links) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ uint16_t cnc_index,
+ uint16_t num_links,
+ const struct TALER_RefreshCommitLinkP *commit_links);
+
+ /**
+ * Obtain the commited (encrypted) refresh link data
+ * for the given refresh session.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection to use
+ * @param session_hash hash to identify refresh session
+ * @param cnc_index cut and choose index (1st dimension)
+ * @param num_links size of the @a links array to return
+ * @param[out] links array link information to return
+ * @return #GNUNET_SYSERR on internal error,
+ * #GNUNET_NO if commitment was not found
+ * #GNUNET_OK on success
+ */
+ int
+ (*get_refresh_commit_links) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ uint16_t cnc_index,
+ uint16_t num_links,
+ struct TALER_RefreshCommitLinkP *links);
+
+
+ /**
+ * Get all of the information from the given melt commit operation.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection to use
+ * @param session_hash hash to identify refresh session
+ * @return NULL if the @a session_hash does not correspond to any known melt
+ * operation
+ */
+ struct TALER_EXCHANGEDB_MeltCommitment *
+ (*get_melt_commitment) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash);
+
+
+ /**
+ * Free information about a melt commitment.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param mc melt commitment data to free
+ */
+ void
+ (*free_melt_commitment) (void *cls,
+ struct TALER_EXCHANGEDB_MeltCommitment *mc);
+
+
+ /**
+ * Insert signature of a new coin generated during refresh into
+ * the database indexed by the refresh session and the index
+ * of the coin. This data is later used should an old coin
+ * be used to try to obtain the private keys during "/refresh/link".
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param session_hash hash to identify refresh session
+ * @param newcoin_index coin index
+ * @param ev_sig coin signature
+ * @return #GNUNET_OK on success
+ */
+ int
+ (*insert_refresh_out) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash,
+ uint16_t newcoin_index,
+ const struct TALER_DenominationSignature *ev_sig);
+
+
+ /**
+ * Obtain the link data of a coin, that is the encrypted link
+ * information, the denomination keys and the signatures.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param session_hash session to get linkage data for
+ * @return all known link data for the session
+ */
+ struct TALER_EXCHANGEDB_LinkDataList *
+ (*get_link_data_list) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *session_hash);
+
+
+ /**
+ * Free memory of the link data list.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param ldl link data list to release
+ */
+ void
+ (*free_link_data_list) (void *cls,
+ struct TALER_EXCHANGEDB_LinkDataList *ldl);
+
+
+ /**
+ * Obtain shared secret and transfer public key from the public key of
+ * the coin. This information and the link information returned by
+ * @e get_link_data_list() enable the owner of an old coin to determine
+ * the private keys of the new coins after the melt.
+ *
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param coin_pub public key of the coin
+ * @param tdc function to call for each session the coin was melted into
+ * @param tdc_cls closure for @a tdc
+ * @return #GNUNET_OK on success,
+ * #GNUNET_NO on failure (not found)
+ * #GNUNET_SYSERR on internal failure (database issue)
+ */
+ int
+ (*get_transfer) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_CoinSpendPublicKeyP *coin_pub,
+ TALER_EXCHANGEDB_TransferDataCallback tdc,
+ void *tdc_cls);
+
+
+ /**
+ * Compile a list of all (historic) transactions performed
+ * with the given coin (/refresh/melt and /deposit operations).
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param coin_pub coin to investigate
+ * @return list of transactions, NULL if coin is fresh
+ */
+ struct TALER_EXCHANGEDB_TransactionList *
+ (*get_coin_transactions) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_CoinSpendPublicKeyP *coin_pub);
+
+
+ /**
+ * Free linked list of transactions.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param list list to free
+ */
+ void
+ (*free_coin_transaction_list) (void *cls,
+ struct TALER_EXCHANGEDB_TransactionList *list);
+
+
+ /**
+ * Lookup the list of Taler transactions that was aggregated
+ * into a wire transfer by the respective @a raw_wtid.
+ *
+ * @param cls the @e cls of this struct with the plugin-specific state
+ * @param session database connection
+ * @param wtid the raw wire transfer identifier we used
+ * @param cb function to call on each transaction found
+ * @param cb_cls closure for @a cb
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on database errors,
+ * #GNUNET_NO if we found no results
+ */
+ int
+ (*lookup_wire_transfer) (void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_WireTransferIdentifierRawP *wtid,
+ TALER_EXCHANGEDB_WireTransferDataCallback cb,
+ void *cb_cls);
+
+
+ /**
+ * Try to find the wire transfer details for a deposit operation.
+ * If we did not execute the deposit yet, return when it is supposed
+ * to be executed.
+ *
+ * @param cls closure
+ * @param session database connection
+ * @param h_contract hash of the contract
+ * @param h_wire hash of merchant wire details
+ * @param coin_pub public key of deposited coin
+ * @param merchant_pub merchant public key
+ * @param transaction_id transaction identifier
+ * @param cb function to call with the result
+ * @param cb_cls closure to pass to @a cb
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on DB errors,
+ * #GNUNET_NO if nothing was found
+ */
+ int
+ (*wire_lookup_deposit_wtid)(void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct GNUNET_HashCode *h_contract,
+ const struct GNUNET_HashCode *h_wire,
+ const struct TALER_CoinSpendPublicKeyP *coin_pub,
+ const struct TALER_MerchantPublicKeyP *merchant_pub,
+ uint64_t transaction_id,
+ TALER_EXCHANGEDB_DepositWtidCallback cb,
+ void *cb_cls);
+
+
+ /**
+ * Function called to insert aggregation information into the DB.
+ *
+ * @param cls closure
+ * @param session database connection
+ * @param wtid the raw wire transfer identifier we used
+ * @param merchant_pub public key of the merchant (should be same for all callbacks with the same @e cls)
+ * @param h_wire hash of wire transfer details of the merchant (should be same for all callbacks with the same @e cls)
+ * @param h_contract which contract was this payment about
+ * @param transaction_id merchant's transaction ID for the payment
+ * @param execution_time when did we execute the transaction
+ * @param coin_pub which public key was this payment about
+ * @param coin_value amount contributed by this coin in total
+ * @param coin_fee deposit fee charged by exchange for this coin
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on DB errors
+ */
+ int
+ (*insert_aggregation_tracking)(void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const struct TALER_WireTransferIdentifierRawP *wtid,
+ const struct TALER_MerchantPublicKeyP *merchant_pub,
+ const struct GNUNET_HashCode *h_wire,
+ const struct GNUNET_HashCode *h_contract,
+ uint64_t transaction_id,
+ struct GNUNET_TIME_Absolute execution_time,
+ const struct TALER_CoinSpendPublicKeyP *coin_pub,
+ const struct TALER_Amount *coin_value,
+ const struct TALER_Amount *coin_fee);
+
+
+ /**
+ * Function called to insert wire transfer commit data into the DB.
+ *
+ * @param cls closure
+ * @param session database connection
+ * @param type type of the wire transfer (i.e. "sepa")
+ * @param buf buffer with wire transfer preparation data
+ * @param buf_size number of bytes in @a buf
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on DB errors
+ */
+ int
+ (*wire_prepare_data_insert)(void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const char *type,
+ const char *buf,
+ size_t buf_size);
+
+
+ /**
+ * Function called to mark wire transfer commit data as finished.
+ *
+ * @param cls closure
+ * @param session database connection
+ * @param rowid which entry to mark as finished
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on DB errors
+ */
+ int
+ (*wire_prepare_data_mark_finished)(void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ unsigned long long rowid);
+
+
+ /**
+ * Function called to get an unfinished wire transfer
+ * preparation data. Fetches at most one item.
+ *
+ * @param cls closure
+ * @param session database connection
+ * @param type type fo the wire transfer (i.e. "sepa")
+ * @param cb function to call for ONE unfinished item
+ * @param cb_cls closure for @a cb
+ * @return #GNUNET_OK on success,
+ * #GNUNET_NO if there are no entries,
+ * #GNUNET_SYSERR on DB errors
+ */
+ int
+ (*wire_prepare_data_get)(void *cls,
+ struct TALER_EXCHANGEDB_Session *session,
+ const char *type,
+ TALER_EXCHANGEDB_WirePreparationCallback cb,
+ void *cb_cls);
+
+
+};
+
+
+#endif /* _TALER_EXCHANGE_DB_H */