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Diffstat (limited to 'src/exchange/taler-exchange-router.c')
| -rw-r--r-- | src/exchange/taler-exchange-router.c | 450 |
1 files changed, 450 insertions, 0 deletions
diff --git a/src/exchange/taler-exchange-router.c b/src/exchange/taler-exchange-router.c new file mode 100644 index 000000000..a1a247194 --- /dev/null +++ b/src/exchange/taler-exchange-router.c @@ -0,0 +1,450 @@ +/* + This file is part of TALER + Copyright (C) 2022 Taler Systems SA + + TALER is free software; you can redistribute it and/or modify it under the + terms of the GNU Affero 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 Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License along with + TALER; see the file COPYING. If not, see <http://www.gnu.org/licenses/> +*/ + +/** + * @file taler-exchange-router.c + * @brief Process that routes P2P payments. Responsible for + * aggregating remote payments into the respective wad transfers. + * Execution of actual wad transfers is still to be done by taler-exchange-transfer, + * and watching for incoming wad transfers is done by taler-exchange-wirewatch. + * @author Christian Grothoff + */ +#include "platform.h" +#include <gnunet/gnunet_util_lib.h> +#include <jansson.h> +#include <pthread.h> +#include "taler_exchangedb_lib.h" +#include "taler_exchangedb_plugin.h" +#include "taler_json_lib.h" +#include "taler_bank_service.h" + + +// FIXME #7271: revisit how (and if) we do sharding! +// Maybe use different helpers for wads than +// for local purses?! +/** + * Work shard we are processing. + */ +struct Shard +{ + + /** + * When did we start processing the shard? + */ + struct GNUNET_TIME_Timestamp start_time; + + /** + * Starting row of the shard. + */ + uint32_t shard_start; + + /** + * Inclusive end row of the shard. + */ + uint32_t shard_end; + + /** + * Number of starting points found in the shard. + */ + uint64_t work_counter; + +}; + + +/** + * What is the smallest unit we support for wire transfers? + * We will need to round down to a multiple of this amount. + */ +static struct TALER_Amount currency_round_unit; + +/** + * What is the base URL of this exchange? Used in the + * wire transfer subjects so that merchants and governments + * can ask for the list of aggregated deposits. + */ +static char *exchange_base_url; + +/** + * Set to #GNUNET_YES if this exchange does not support KYC checks + * and thus P2P transfers are to be made regardless of the + * KYC status of the target reserve. + */ +static int kyc_off; + +/** + * The exchange's configuration. + */ +static const struct GNUNET_CONFIGURATION_Handle *cfg; + +/** + * Our database plugin. + */ +static struct TALER_EXCHANGEDB_Plugin *db_plugin; + +/** + * Next task to run, if any. + */ +static struct GNUNET_SCHEDULER_Task *task; + +/** + * How long should we sleep when idle before trying to find more work? + */ +static struct GNUNET_TIME_Relative router_idle_sleep_interval; + +/** + * How big are the shards we are processing? Is an inclusive offset, so every + * shard ranges from [X,X+shard_size) exclusive. So a shard covers + * shard_size slots. The maximum value for shard_size is INT32_MAX+1. + */ +static uint32_t shard_size; + +/** + * Value to return from main(). 0 on success, non-zero on errors. + */ +static int global_ret; + +/** + * #GNUNET_YES if we are in test mode and should exit when idle. + */ +static int test_mode; + + +/** + * Select a shard to work on. + * + * @param cls NULL + */ +static void +run_shard (void *cls); + + +/** + * We're being aborted with CTRL-C (or SIGTERM). Shut down. + * + * @param cls closure + */ +static void +shutdown_task (void *cls) +{ + (void) cls; + GNUNET_log (GNUNET_ERROR_TYPE_INFO, + "Running shutdown\n"); + if (NULL != task) + { + GNUNET_SCHEDULER_cancel (task); + task = NULL; + } + TALER_EXCHANGEDB_plugin_unload (db_plugin); + db_plugin = NULL; + TALER_EXCHANGEDB_unload_accounts (); + cfg = NULL; +} + + +/** + * Parse the configuration for wirewatch. + * + * @return #GNUNET_OK on success + */ +static enum GNUNET_GenericReturnValue +parse_wirewatch_config (void) +{ + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_string (cfg, + "exchange", + "BASE_URL", + &exchange_base_url)) + { + GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, + "exchange", + "BASE_URL"); + return GNUNET_SYSERR; + } + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_time (cfg, + "exchange", + "ROUTER_IDLE_SLEEP_INTERVAL", + &router_idle_sleep_interval)) + { + GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, + "exchange", + "ROUTER_IDLE_SLEEP_INTERVAL"); + return GNUNET_SYSERR; + } + if ( (GNUNET_OK != + TALER_config_get_amount (cfg, + "taler", + "CURRENCY_ROUND_UNIT", + ¤cy_round_unit)) || + ( (0 != currency_round_unit.fraction) && + (0 != currency_round_unit.value) ) ) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Need non-zero value in section `TALER' under `CURRENCY_ROUND_UNIT'\n"); + return GNUNET_SYSERR; + } + + if (NULL == + (db_plugin = TALER_EXCHANGEDB_plugin_load (cfg))) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Failed to initialize DB subsystem\n"); + return GNUNET_SYSERR; + } + if (GNUNET_OK != + TALER_EXCHANGEDB_load_accounts (cfg, + TALER_EXCHANGEDB_ALO_DEBIT)) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "No wire accounts configured for debit!\n"); + TALER_EXCHANGEDB_plugin_unload (db_plugin); + db_plugin = NULL; + return GNUNET_SYSERR; + } + return GNUNET_OK; +} + + +/** + * Perform a database commit. If it fails, print a warning. + * + * @return status of commit + */ +static enum GNUNET_DB_QueryStatus +commit_or_warn (void) +{ + enum GNUNET_DB_QueryStatus qs; + + qs = db_plugin->commit (db_plugin->cls); + if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs) + return qs; + GNUNET_log ((GNUNET_DB_STATUS_SOFT_ERROR == qs) + ? GNUNET_ERROR_TYPE_INFO + : GNUNET_ERROR_TYPE_ERROR, + "Failed to commit database transaction!\n"); + return qs; +} + + +/** + * Release lock on shard @a s in the database. + * On error, terminates this process. + * + * @param[in] s shard to free (and memory to release) + */ +static void +release_shard (struct Shard *s) +{ + enum GNUNET_DB_QueryStatus qs; + + qs = db_plugin->release_revolving_shard ( + db_plugin->cls, + "router", + s->shard_start, + s->shard_end); + GNUNET_free (s); + switch (qs) + { + case GNUNET_DB_STATUS_HARD_ERROR: + case GNUNET_DB_STATUS_SOFT_ERROR: + GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR != qs); + GNUNET_break (0); + GNUNET_SCHEDULER_shutdown (); + return; + case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS: + /* Strange, but let's just continue */ + break; + case GNUNET_DB_STATUS_SUCCESS_ONE_RESULT: + /* normal case */ + break; + } +} + + +static void +run_routing (void *cls) +{ + struct Shard *s = cls; + + task = NULL; + GNUNET_log (GNUNET_ERROR_TYPE_INFO, + "Checking for ready P2P transfers to route\n"); + // FIXME #7271: do actual work here! + commit_or_warn (); + release_shard (s); + task = GNUNET_SCHEDULER_add_now (&run_shard, + NULL); +} + + +/** + * Select a shard to work on. + * + * @param cls NULL + */ +static void +run_shard (void *cls) +{ + struct Shard *s; + enum GNUNET_DB_QueryStatus qs; + + (void) cls; + task = NULL; + if (GNUNET_SYSERR == + db_plugin->preflight (db_plugin->cls)) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Failed to obtain database connection!\n"); + global_ret = EXIT_FAILURE; + GNUNET_SCHEDULER_shutdown (); + return; + } + s = GNUNET_new (struct Shard); + s->start_time = GNUNET_TIME_timestamp_get (); + qs = db_plugin->begin_revolving_shard (db_plugin->cls, + "router", + shard_size, + 1U + INT32_MAX, + &s->shard_start, + &s->shard_end); + if (0 >= qs) + { + if (GNUNET_DB_STATUS_SOFT_ERROR == qs) + { + static struct GNUNET_TIME_Relative delay; + + GNUNET_free (s); + delay = GNUNET_TIME_randomized_backoff (delay, + GNUNET_TIME_UNIT_SECONDS); + task = GNUNET_SCHEDULER_add_delayed (delay, + &run_shard, + NULL); + return; + } + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Failed to begin shard (%d)!\n", + qs); + GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR != qs); + global_ret = EXIT_FAILURE; + GNUNET_SCHEDULER_shutdown (); + return; + } + GNUNET_log (GNUNET_ERROR_TYPE_INFO, + "Starting shard [%u:%u]!\n", + (unsigned int) s->shard_start, + (unsigned int) s->shard_end); + task = GNUNET_SCHEDULER_add_now (&run_routing, + s); +} + + +/** + * First task. + * + * @param cls closure, NULL + * @param args remaining command-line arguments + * @param cfgfile name of the configuration file used (for saving, can be NULL!) + * @param c configuration + */ +static void +run (void *cls, + char *const *args, + const char *cfgfile, + const struct GNUNET_CONFIGURATION_Handle *c) +{ + unsigned long long ass; + (void) cls; + (void) args; + (void) cfgfile; + + cfg = c; + if (GNUNET_OK != parse_wirewatch_config ()) + { + cfg = NULL; + global_ret = EXIT_NOTCONFIGURED; + return; + } + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_number (cfg, + "exchange", + "ROUTER_SHARD_SIZE", + &ass)) + { + cfg = NULL; + global_ret = EXIT_NOTCONFIGURED; + return; + } + if ( (0 == ass) || + (ass > INT32_MAX) ) + shard_size = 1U + INT32_MAX; + else + shard_size = (uint32_t) ass; + GNUNET_assert (NULL == task); + task = GNUNET_SCHEDULER_add_now (&run_shard, + NULL); + GNUNET_SCHEDULER_add_shutdown (&shutdown_task, + cls); +} + + +/** + * The main function of the taler-exchange-router. + * + * @param argc number of arguments from the command line + * @param argv command line arguments + * @return 0 ok, non-zero on error, see #global_ret + */ +int +main (int argc, + char *const *argv) +{ + struct GNUNET_GETOPT_CommandLineOption options[] = { + GNUNET_GETOPT_option_timetravel ('T', + "timetravel"), + GNUNET_GETOPT_option_flag ('t', + "test", + "run in test mode and exit when idle", + &test_mode), + GNUNET_GETOPT_option_flag ('y', + "kyc-off", + "perform wire transfers without KYC checks", + &kyc_off), + GNUNET_GETOPT_OPTION_END + }; + enum GNUNET_GenericReturnValue ret; + + if (GNUNET_OK != + GNUNET_STRINGS_get_utf8_args (argc, argv, + &argc, &argv)) + return EXIT_INVALIDARGUMENT; + TALER_OS_init (); + ret = GNUNET_PROGRAM_run ( + argc, argv, + "taler-exchange-router", + gettext_noop ( + "background process that routes P2P transfers"), + options, + &run, NULL); + GNUNET_free_nz ((void *) argv); + if (GNUNET_SYSERR == ret) + return EXIT_INVALIDARGUMENT; + if (GNUNET_NO == ret) + return EXIT_SUCCESS; + return global_ret; +} + + +/* end of taler-exchange-router.c */ |