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#include "platform.h"
#include <jansson.h>
#include <taler/taler_signatures.h>
#include <gnunet/gnunet_util_lib.h>
#include "merchant.h"
#include "merchant_db.h"
#include "taler_merchant_contract_lib.h"
/* TODO: make this file a library, and programmatically call the following
* functions */
/**
* Macro to round microseconds to seconds in GNUNET_TIME_* structs.
*/
#define ROUND_TO_SECS(name,us_field) name.us_field -= name.us_field % (1000 * 1000)
/**
* Shorthand for exit jumps.
*/
#define EXITIF(cond) \
do { \
if (cond) { GNUNET_break (0); goto EXITIF_exit; } \
} while (0)
/**
* Generate the hash containing the information (= a nounce + merchant's IBAN) to
* redeem money from mint in a subsequent /deposit operation
* @param nounce the nounce
* @param wire the merchant's wire details
* @return the hash to be included in the contract's blob
*
*/
static struct GNUNET_HashCode
hash_wireformat (uint64_t nounce, const struct MERCHANT_WIREFORMAT_Sepa *wire)
{
struct GNUNET_HashContext *hc;
struct GNUNET_HashCode hash;
hc = GNUNET_CRYPTO_hash_context_start ();
GNUNET_CRYPTO_hash_context_read (hc, wire->iban, strlen (wire->iban));
GNUNET_CRYPTO_hash_context_read (hc, wire->name, strlen (wire->name));
GNUNET_CRYPTO_hash_context_read (hc, wire->bic, strlen (wire->bic));
nounce = GNUNET_htonll (nounce);
GNUNET_CRYPTO_hash_context_read (hc, &nounce, sizeof (nounce));
GNUNET_CRYPTO_hash_context_finish (hc, &hash);
return hash;
}
/**
* Take the global wire details and return a JSON containing them,
* compliantly with the Taler's API.
* @param wire the merchant's wire details
* @param nounce the nounce for hashing the wire details with
* @param edate when the beneficiary wants this transfer to take place
* @return JSON representation of the wire details, NULL upon errors
*/
json_t *
MERCHANT_get_wire_json (const struct MERCHANT_WIREFORMAT_Sepa *wire,
uint64_t nounce,
const struct GNUNET_TIME_Absolute edate)
{
json_t *root;
json_t *j_edate;
json_t *j_nounce;
nounce = GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_NONCE, UINT64_MAX);
j_nounce = json_integer (nounce);
j_edate = TALER_json_from_abs (edate);
if (NULL == (root = json_pack ("{s:s, s:s, s:s, s:s, s:o}",
"type", "SEPA",
"IBAN", wire->iban,
"name", wire->name,
"BIC", wire->bic,
"edate", j_edate,
"r", json_integer_value (j_nounce))))
return NULL;
return root;
}
/**
* Take from the frontend the (partly) generated contract and fill
* the missing values in it; for example, the SEPA details.
* Moreover, it stores the contract in the DB.
* @param j_contract parsed contract, originated by the frontend. It will be
* hold the new values.
* @param db_conn the handle to the local DB
* @param contract where to store the (subset of the) contract to be (still) signed
* @param timestamp contract's timestamp (shall be generated by the merchant)
* @param expiry the time when the contract will expire
* @param edate when the merchant wants to receive the wire transfer corresponding
* to this deal (this value is also a field inside the 'wire' JSON format)
* @param nounce the nounce used to hash the wire details
* @param contract_str where to store the (stringified) contract
* @return GNUNET_OK on success; GNUNET_SYSERR upon errors
*/
/**
* TODO: inspect reference counting and, accordingly, free those json_t*(s)
* still allocated */
uint32_t
MERCHANT_handle_contract (const json_t *j_contract,
PGconn *db_conn,
struct Contract *contract,
struct GNUNET_TIME_Absolute timestamp,
struct GNUNET_TIME_Absolute expiry,
struct GNUNET_TIME_Absolute edate,
uint64_t nounce,
const char *contract_str)
{
json_t *j_amount;
json_int_t j_product_id;
json_int_t j_trans_id;
struct TALER_Amount amount;
/* Extracting values useful for DB work. Only gettable from the JSON
since they are generated by the frontend */
if (-1 == json_unpack (j_contract, "{s:o, s:I, s:{s:{s:I}}}",
"amount", &j_amount,
"trans_id", &j_trans_id,
"details", "items",
"product_id", &j_product_id))
{
printf ("no unpacking\n");
return GNUNET_SYSERR;
}
/* needed for DB work */
TALER_json_to_amount (j_amount, &amount); // produces a WARNING..
contract_str = json_dumps (j_contract, JSON_COMPACT | JSON_PRESERVE_ORDER);
GNUNET_CRYPTO_hash (contract_str, strlen (contract_str) + 1,
&contract->h_contract_details);
contract->purpose.purpose = htonl (TALER_SIGNATURE_MERCHANT_CONTRACT);
contract->purpose.size = htonl (sizeof (struct Contract));
// DB mgmt
if (GNUNET_SYSERR == MERCHANT_DB_contract_create (db_conn,
timestamp,
expiry,
edate,
&amount,
&contract->h_contract_details,
(uint64_t) j_trans_id, // safe?
contract_str,
nounce,
(uint64_t) j_product_id))
return GNUNET_SYSERR;
return GNUNET_OK;
}
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