/*
This file is part of TALER
Copyright (C) 2014, 2015 Christian Grothoff (and other contributing authors)
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
*/
/**
* @file mint/taler_mintdb_plugin.h
* @brief Low-level (statement-level) database access for the mint
* @author Florian Dold
* @author Christian Grothoff
*/
#ifndef TALER_MINTDB_PLUGIN_H
#define TALER_MINTDB_PLUGIN_H
#include
#include "taler_util.h"
/**
* Information we keep on bank transfer(s) that established a reserve.
*/
struct BankTransfer
{
/**
* Public key of the reserve that was filled.
*/
struct TALER_ReservePublicKey reserve_pub;
/**
* Amount that was transferred to the mint.
*/
struct TALER_Amount amount;
/**
* Detailed wire information about the transaction.
*/
json_t *wire;
};
/**
* A summary of a Reserve
*/
struct Reserve
{
/**
* The reserve's public key. This uniquely identifies the reserve
*/
struct TALER_ReservePublicKey pub;
/**
* The balance amount existing in the reserve
*/
struct TALER_Amount balance;
/**
* The expiration date of this reserve
*/
struct GNUNET_TIME_Absolute expiry;
};
/**
* Information we keep for a withdrawn coin to reproduce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 CollectableBlindcoin
{
/**
* Our signature over the (blinded) coin.
*/
struct TALER_DenominationSignature sig;
/**
* Denomination key (which coin was generated).
* FIXME: we should probably instead have the
* AMOUNT *including* fee in what is being signed
* as well!
*/
struct TALER_DenominationPublicKey denom_pub;
/**
* Public key of the reserve that was drained.
*/
struct TALER_ReservePublicKey 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_ReserveSignature reserve_sig;
};
/**
* Types of operations on a reserved.
*/
enum TALER_MINT_DB_ReserveOperation
{
/**
* Money was deposited into the reserve via a bank transfer.
*/
TALER_MINT_DB_RO_BANK_TO_MINT = 0,
/**
* A Coin was withdrawn from the reserve using /withdraw.
*/
TALER_MINT_DB_RO_WITHDRAW_COIN = 1
};
/**
* 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 ReserveHistory
{
/**
* Next entry in the reserve history.
*/
struct ReserveHistory *next;
/**
* Type of the event, determins @e details.
*/
enum TALER_MINT_DB_ReserveOperation type;
/**
* Details of the operation, depending on @e type.
*/
union
{
/**
* Details about a bank transfer to the mint.
*/
struct BankTransfer *bank;
/**
* Details about a /withdraw operation.
*/
struct CollectableBlindcoin *withdraw;
} details;
};
/**
* Specification for a /deposit operation.
*/
struct 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_CoinSpendSignature csig;
/**
* Public key of the merchant. Enables later identification
* of the merchant in case of a need to rollback transactions.
*/
struct TALER_MerchantPublicKey merchant_pub;
/**
* Hash over the contract between merchant and customer
* (remains unknown to the Mint).
*/
struct GNUNET_HashCode h_contract;
/**
* Hash of the (canonical) representation of @e wire, used
* to check the signature on the request. Generated by
* the mint 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;
/**
* 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;
};
/**
* Global information for a refreshing session. Includes
* dimensions of the operation, security parameters and
* client signatures from "/refresh/melt" and "/refresh/commit".
*/
struct RefreshSession
{
/**
* Number of coins we are melting.
*/
uint16_t num_oldcoins;
/**
* Number of new coins we are creating.
*/
uint16_t num_newcoins;
/**
* Number of parallel operations we perform for the cut and choose.
* (must be greater or equal to three for security). 0 if not yet
* known.
*/
uint16_t kappa;
/**
* Index (smaller @e kappa) which the mint has chosen to not
* have revealed during cut and choose.
*/
uint16_t noreveal_index;
};
/**
* Specification for coin in a /refresh/melt operation.
*/
struct RefreshMelt
{
/**
* Information about the coin that is being melted.
*/
struct TALER_CoinPublicInfo coin;
/**
* Signature over the melting operation.
*/
struct TALER_CoinSpendSignature 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;
};
/**
* We have as many `struct RefreshCommitCoin` as there are new
* coins being created by the refresh (for each of the kappa
* sets). These are the coins we ask the mint to sign if the
* respective set is selected.
*/
struct 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;
};
GNUNET_NETWORK_STRUCT_BEGIN
/**
* For each (old) coin being melted, we have a `struct
* RefreshCommitLink` that allows the user to find the shared secret
* to decrypt the respective refresh links for the new coins in the
* `struct RefreshCommitCoin`.
*/
struct RefreshCommitLink
{
/**
* Transfer public key, used to decrypt the @e shared_secret_enc
* in combintation with the corresponding private key of the
* coin.
*/
struct TALER_TransferPublicKey transfer_pub;
/**
* Encrypted shared secret to decrypt the link.
*/
struct TALER_EncryptedLinkSecret shared_secret_enc;
};
GNUNET_NETWORK_STRUCT_END
/**
* Linked list of refresh information linked to a coin.
*/
struct LinkDataList
{
/**
* Information is stored in a NULL-terminated linked list.
*/
struct 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;
};
/**
* Specification for a /lock operation.
*/
struct Lock
{
/**
* Information about the coin that is being locked.
*/
struct TALER_CoinPublicInfo coin;
/**
* Signature over the locking operation.
*/
struct TALER_CoinSpendSignature coin_sig;
/**
* How much value is being locked?
*/
struct TALER_Amount amount;
// FIXME: more needed...
};
/**
* Enumeration to classify the different types of transactions
* that can be done with a coin.
*/
enum TALER_MINT_DB_TransactionType
{
/**
* /deposit operation.
*/
TALER_MINT_DB_TT_DEPOSIT = 0,
/**
* /refresh/melt operation.
*/
TALER_MINT_DB_TT_REFRESH_MELT = 1,
/**
* /lock operation.
*/
TALER_MINT_DB_TT_LOCK = 2
};
/**
* List of transactions we performed for a particular coin.
*/
struct TALER_MINT_DB_TransactionList
{
/**
* Next pointer in the NULL-terminated linked list.
*/
struct TALER_MINT_DB_TransactionList *next;
/**
* Type of the transaction, determines what is stored in @e details.
*/
enum TALER_MINT_DB_TransactionType type;
/**
* Details about the transaction, depending on @e type.
*/
union
{
/**
* Details if transaction was a /deposit operation.
*/
struct Deposit *deposit;
/**
* Details if transaction was a /refresh/melt operation.
*/
struct RefreshMelt *melt;
/**
* Details if transaction was a /lock operation.
*/
struct Lock *lock;
} details;
};
/**
* Handle for a database session (per-thread, for transactions).
*/
struct TALER_MINTDB_Session;
/**
* The plugin API, returned from the plugin's "init" function.
* The argument given to "init" is simply a configuration handle.
*/
struct TALER_MINTDB_Plugin
{
/**
* Closure for all callbacks.
*/
void *cls;
/**
* 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_MINTDB_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_MINTDB_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 sesssion connection to use
* @return #GNUNET_OK on success
*/
int
(*start) (void *cls,
struct TALER_MINTDB_Session *sesssion);
/**
* Commit a transaction.
*
* @param cls the @e cls of this struct with the plugin-specific state
* @param sesssion connection to use
* @return #GNUNET_OK on success
*/
int
(*commit) (void *cls,
struct TALER_MINTDB_Session *sesssion);
/**
* Abort/rollback a transaction.
*
* @param cls the @e cls of this struct with the plugin-specific state
* @param sesssion connection to use
*/
void
(*rollback) (void *cls,
struct TALER_MINTDB_Session *sesssion);
/**
* 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 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_MINTDB_Session *db,
struct Reserve *reserve);
/* FIXME: add functions to add bank transfers to our DB
(and to test if we already did add one) (#3633/#3717) */
/**
* Insert a incoming transaction into reserves. New reserves are also created
* through this function.
*
* @param cls the @e cls of this struct with the plugin-specific state
* @param db the database connection handle
* @param reserve the reserve structure. The public key of the reserve should
* be set here. Upon successful execution of this function, the
* balance and expiration of the reserve will be updated.
* @param balance the amount that has to be added to the reserve
* @param expiry the new expiration time for the reserve
* @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failures
*/
int
(*reserves_in_insert) (void *cls,
struct TALER_MINTDB_Session *db,
struct Reserve *reserve,
const struct TALER_Amount *balance,
const struct GNUNET_TIME_Absolute expiry);
/**
* 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 sesssion database connection to use
* @param h_blind hash of the blinded message
* @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_collectable_blindcoin) (void *cls,
struct TALER_MINTDB_Session *sesssion,
const struct GNUNET_HashCode *h_blind,
struct 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 sesssion database connection to use
* @param h_blind hash of the blinded message
* @param withdraw amount by which the reserve will be withdrawn with this
* transaction
* @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_collectable_blindcoin) (void *cls,
struct TALER_MINTDB_Session *sesssion,
const struct GNUNET_HashCode *h_blind,
struct TALER_Amount withdraw,
const struct 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 sesssion connection to use
* @param reserve_pub public key of the reserve
* @return known transaction history (NULL if reserve is unknown)
*/
struct ReserveHistory *
(*get_reserve_history) (void *cls,
struct TALER_MINTDB_Session *sesssion,
const struct TALER_ReservePublicKey *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 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 sesssion database connection
* @param deposit deposit to search for
* @return #GNUNET_YES if we know this operation,
* #GNUNET_NO if this deposit is unknown to us,
* #GNUNET_SYSERR on internal error
*/
int
(*have_deposit) (void *cls,
struct TALER_MINTDB_Session *sesssion,
const struct Deposit *deposit);
/**
* Insert information about deposited coin into the
* database.
*
* @param cls the @e cls of this struct with the plugin-specific state
* @param sesssion 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_MINTDB_Session *sesssion,
const struct Deposit *deposit);
/**
* Lookup refresh session data under the given @a session_hash.
*
* @param cls the @e cls of this struct with the plugin-specific state
* @param sesssion database handle to use
* @param session_hash hash over the melt to use for the lookup
* @param refresh_session[OUT] 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_MINTDB_Session *sesssion,
const struct GNUNET_HashCode *session_hash,
struct 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 sesssion 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_MINTDB_Session *sesssion,
const struct GNUNET_HashCode *session_hash,
const struct 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 sesssion 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_MINTDB_Session *sesssion,
uint16_t oldcoin_index,
const struct 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 sesssion 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
* @return #GNUNET_OK on success
* #GNUNET_SYSERR on internal error
*/
int
(*get_refresh_melt) (void *cls,
struct TALER_MINTDB_Session *sesssion,
const struct GNUNET_HashCode *session_hash,
uint16_t oldcoin_index,
struct 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 sesssion 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_MINTDB_Session *sesssion,
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 sesssion database connection
* @param session_hash hash to identify refresh session
* @param num_newcoins size of the @a denom_pubs array
* @param denom_pubs[OUT] 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_MINTDB_Session *sesssion,
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 sesssion database connection to use
* @param session_hash hash to identify refresh session
* @param i set index (1st dimension), relating to 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_MINTDB_Session *sesssion,
const struct GNUNET_HashCode *session_hash,
unsigned int i,
unsigned int num_newcoins,
const struct 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 sesssion database connection to use
* @param session_hash hash to identify refresh session
* @param i set index (1st dimension)
* @param num_coins size of the @a commit_coins array
* @param commit_coin[OUT] 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_MINTDB_Session *sesssion,
const struct GNUNET_HashCode *session_hash,
unsigned int i,
unsigned int num_coins,
struct 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 sesssion database connection to use
* @param session_hash hash to identify refresh session
* @param i set index (1st dimension), relating to 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_MINTDB_Session *sesssion,
const struct GNUNET_HashCode *session_hash,
unsigned int i,
unsigned int num_links,
const struct RefreshCommitLink *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 sesssion database connection to use
* @param session_hash hash to identify refresh session
* @param i set index (1st dimension)
* @param num_links size of the @links array to return
* @param links[OUT] 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_MINTDB_Session *sesssion,
const struct GNUNET_HashCode *session_hash,
unsigned int i,
unsigned int num_links,
struct RefreshCommitLink *links);
/**
* 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 sesssion 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_collectable) (void *cls,
struct TALER_MINTDB_Session *sesssion,
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 sesssion database connection
* @param coin_pub public key to use to retrieve linkage data
* @return all known link data for the coin
*/
struct LinkDataList *
(*get_link_data_list) (void *cls,
struct TALER_MINTDB_Session *sesssion,
const struct TALER_CoinSpendPublicKey *coin_pub);
/**
* 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 LinkDataList *ldl);
/**
* Obtain shared secret and transfer public key from the public key of
* the coin. This information and the link information returned by
* #TALER_db_get_link() 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 sesssion database connection
* @param coin_pub public key of the coin
* @param transfer_pub[OUT] public transfer key
* @param shared_secret_enc[OUT] set to shared secret
* @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_MINTDB_Session *sesssion,
const struct TALER_CoinSpendPublicKey *coin_pub,
struct TALER_TransferPublicKey *transfer_pub,
struct TALER_EncryptedLinkSecret *shared_secret_enc);
/**
* Test if the given /lock request is known to us.
*
* @param cls the @e cls of this struct with the plugin-specific state
* @param sesssion database connection
* @param lock lock operation
* @return #GNUNET_YES if known,
* #GNUENT_NO if not,
* #GNUNET_SYSERR on internal error
*/
int
(*have_lock) (void *cls,
struct TALER_MINTDB_Session *sesssion,
const struct Lock *lock);
/**
* Store the given /lock request in the database.
*
* @param cls the @e cls of this struct with the plugin-specific state
* @param sesssion database connection
* @param lock lock operation
* @return #GNUNET_OK on success
* #GNUNET_SYSERR on internal error
*/
int
(*insert_lock) (void *cls,
struct TALER_MINTDB_Session *sesssion,
const struct Lock *lock);
/**
* 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 sesssion database connection
* @param coin_pub coin to investigate
* @return list of transactions, NULL if coin is fresh
*/
struct TALER_MINT_DB_TransactionList *
(*get_coin_transactions) (void *cls,
struct TALER_MINTDB_Session *sesssion,
const struct TALER_CoinSpendPublicKey *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_MINT_DB_TransactionList *list);
};
#endif /* _NEURO_MINT_DB_H */