diff options
Diffstat (limited to 'src/wire-plugins/plugin_wire_taler-bank.c')
| -rw-r--r-- | src/wire-plugins/plugin_wire_taler-bank.c | 1284 |
1 files changed, 1284 insertions, 0 deletions
diff --git a/src/wire-plugins/plugin_wire_taler-bank.c b/src/wire-plugins/plugin_wire_taler-bank.c new file mode 100644 index 000000000..2d2235343 --- /dev/null +++ b/src/wire-plugins/plugin_wire_taler-bank.c @@ -0,0 +1,1284 @@ +/* + This file is part of TALER + Copyright (C) 2017, 2018 Taler Systems SA + + 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, see <http://www.gnu.org/licenses/> +*/ + +/** + * @file plugin_wire_taler_bank.c + * @brief plugin for the "x-taler-bank" wire method + * @author Christian Grothoff + */ +#include "platform.h" +#include "taler_wire_plugin.h" +#include "taler_json_lib.h" +#include "taler_bank_service.h" +#include "taler_signatures.h" +#include <gnunet/gnunet_curl_lib.h> + +/* only for HTTP status codes */ +#include <microhttpd.h> + +/** + * Maximum legal 'value' for an account number, based on IEEE double (for JavaScript compatibility). + */ +#define MAX_ACCOUNT_NO (1LLU << 52) + +/** + * Type of the "cls" argument given to each of the functions in + * our API. + */ +struct TalerBankClosure +{ + + /** + * Which currency do we support? + */ + char *currency; + + /** + * Handle to the context for sending funds to the bank. + */ + struct GNUNET_CURL_Context *ctx; + + /** + * Scheduler context for running the @e ctx. + */ + struct GNUNET_CURL_RescheduleContext *rc; + + /** + * Configuration we use to lookup account information. + */ + struct GNUNET_CONFIGURATION_Handle *cfg; + +}; + + +/** + * Handle returned by #taler_bank_prepare_wire_transfer. + */ +struct TALER_WIRE_PrepareHandle +{ + + /** + * Task we use for async execution. + */ + struct GNUNET_SCHEDULER_Task *task; + + /** + * TalerBank closure we run in. + */ + struct TalerBankClosure *tc; + + /** + * Authentication information. + */ + struct TALER_BANK_AuthenticationData auth; + + /** + * Which account should be debited? Given as the respective + * section in the configuration file. + */ + char *origin_account_url; + + /** + * Which account should be credited? + */ + char *destination_account_url; + + /** + * Base URL to use for the exchange. + */ + char *exchange_base_url; + + /** + * Function to call with the serialized data. + */ + TALER_WIRE_PrepareTransactionCallback ptc; + + /** + * Closure for @e ptc. + */ + void *ptc_cls; + + /** + * Amount to transfer. + */ + struct TALER_Amount amount; + + /** + * Subject of the wire transfer. + */ + struct TALER_WireTransferIdentifierRawP wtid; + + +}; + + +/** + * Handle returned by #taler_bank_execute_wire_transfer. + */ +struct TALER_WIRE_ExecuteHandle +{ + + /** + * Handle to the HTTP request to the bank. + */ + struct TALER_BANK_AdminAddIncomingHandle *aaih; + + /** + * Function to call with the result. + */ + TALER_WIRE_ConfirmationCallback cc; + + /** + * Closure for @e cc. + */ + void *cc_cls; +}; + + +/** + * Round amount DOWN to the amount that can be transferred via the wire + * method. For example, Taler may support 0.000001 EUR as a unit of + * payment, but SEPA only supports 0.01 EUR. This function would + * round 0.125 EUR to 0.12 EUR in this case. + * + * @param cls the @e cls of this struct with the plugin-specific state + * @param[in,out] amount amount to round down + * @return #GNUNET_OK on success, #GNUNET_NO if rounding was unnecessary, + * #GNUNET_SYSERR if the amount or currency was invalid + */ +static int +taler_bank_amount_round (void *cls, + struct TALER_Amount *amount) +{ + struct TalerBankClosure *tc = cls; + uint32_t delta; + + if (NULL == tc->currency) + { + GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, + "taler", + "CURRENCY"); + return GNUNET_SYSERR; /* not configured with currency */ + } + if (0 != strcasecmp (amount->currency, + tc->currency)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + /* 'taler_bank' method supports 1/100 of the unit currency, i.e. 0.01 CUR */ + delta = amount->fraction % (TALER_AMOUNT_FRAC_BASE / 100); + if (0 == delta) + return GNUNET_NO; + amount->fraction -= delta; + return GNUNET_OK; +} + + +/** + * Information about an account extracted from a payto://-URL. + */ +struct Account +{ + /** + * Hostname of the bank (possibly including port). + */ + char *hostname; + + /** + * Bank account number. + */ + unsigned long long no; +}; + + +/** + * Parse payto:// account URL (only account information, + * wire subject and amount are ignored). + * + * @param account_url URL to parse + * @param account[out] set to information, can be NULL + * @return #TALER_EC_NONE if @a account_url is well-formed + */ +static enum TALER_ErrorCode +parse_payto (const char *account_url, + struct Account *r_account) +{ + const char *hostname; + const char *account; + const char *q; + unsigned long long no; + +#define PREFIX "payto://x-taler-bank/" + if (0 != strncasecmp (account_url, + PREFIX, + strlen (PREFIX))) + return TALER_EC_PAYTO_WRONG_METHOD; + hostname = &account_url[strlen (PREFIX)]; + if (NULL == (account = strchr (hostname, + (unsigned char) '/'))) + return TALER_EC_PAYTO_MALFORMED; + account++; + if (NULL != (q = strchr (account, + (unsigned char) '?'))) + { + char *s; + + s = GNUNET_strndup (account, + q - account); + if (1 != sscanf (s, + "%llu", + &no)) + { + GNUNET_free (s); + return TALER_EC_PAYTO_MALFORMED; + } + GNUNET_free (s); + } + else + { + if (1 != sscanf (account, + "%llu", + &no)) + return TALER_EC_PAYTO_MALFORMED; + } + if (no > MAX_ACCOUNT_NO) + return TALER_EC_PAYTO_MALFORMED; + if (NULL != r_account) + { + r_account->hostname = GNUNET_strndup (hostname, + account - hostname); + r_account->no = no; + } + return TALER_EC_NONE; +} + + +/** + * Check if the given payto:// URL is correctly formatted. + * + * @param cls the @e cls of this struct with the plugin-specific state + * @param account_url an account URL + * @return #TALER_EC_NONE if correctly formatted + */ +static enum TALER_ErrorCode +taler_bank_wire_validate (void *cls, + const char *account_url) +{ + (void) cls; + + return parse_payto (account_url, + NULL); +} + + +GNUNET_NETWORK_STRUCT_BEGIN +/** + * Format we used for serialized transaction data. + */ +struct BufFormatP +{ + + /** + * The wire transfer identifier. + */ + struct TALER_WireTransferIdentifierRawP wtid; + + /** + * The amount. + */ + struct TALER_AmountNBO amount; + + /* followed by 0-terminated origin account URL */ + + /* followed by 0-terminated destination account URL */ + + /* followed by 0-terminated exchange base URL */ + + /* optionally followed by 0-terminated origin username URL */ + + /* optionally followed by 0-terminated origin password URL */ + +}; +GNUNET_NETWORK_STRUCT_END + + +/** + * Abort preparation of a wire transfer. For example, + * because we are shutting down. + * + * @param cls the @e cls of this struct with the plugin-specific state + * @param pth preparation to cancel + */ +static void +taler_bank_prepare_wire_transfer_cancel (void *cls, + struct TALER_WIRE_PrepareHandle *pth) +{ + if (NULL != pth->task) + GNUNET_SCHEDULER_cancel (pth->task); + TALER_BANK_auth_free (&pth->auth); + GNUNET_free (pth->origin_account_url); + GNUNET_free (pth->destination_account_url); + GNUNET_free (pth->exchange_base_url); + GNUNET_free (pth); +} + + +/** + * Prepare for exeuction of a wire transfer. Calls the + * callback with the serialized state. + * + * @param cls the `struct TALER_WIRE_PrepareHandle` + */ +static void +do_prepare (void *cls) +{ + struct TALER_WIRE_PrepareHandle *pth = cls; + size_t len_i; + size_t len_o; + size_t len_au; + size_t len_ap; + size_t len_b; + struct BufFormatP bf; + + pth->task = NULL; + /* serialize the state into a 'buf' */ + len_o = strlen (pth->origin_account_url) + 1; + len_i = strlen (pth->destination_account_url) + 1; + len_b = strlen (pth->exchange_base_url) + 1; + switch (pth->auth.method) + { + case TALER_BANK_AUTH_NONE: + len_au = 0; + len_ap = 0; + break; + case TALER_BANK_AUTH_BASIC: + len_au = strlen (pth->auth.details.basic.username) + 1; + len_ap = strlen (pth->auth.details.basic.password) + 1; + break; + } + bf.wtid = pth->wtid; + TALER_amount_hton (&bf.amount, + &pth->amount); + { + char buf[sizeof (struct BufFormatP) + len_o + len_i + len_b + len_au + len_ap]; + + memcpy (buf, + &bf, + sizeof (struct BufFormatP)); + memcpy (&buf[sizeof (struct BufFormatP)], + pth->origin_account_url, + len_o); + memcpy (&buf[sizeof (struct BufFormatP) + len_o], + pth->destination_account_url, + len_i); + memcpy (&buf[sizeof (struct BufFormatP) + len_o + len_i], + pth->exchange_base_url, + len_b); + switch (pth->auth.method) + { + case TALER_BANK_AUTH_NONE: + break; + case TALER_BANK_AUTH_BASIC: + memcpy (&buf[sizeof (struct BufFormatP) + len_o + len_i + len_b], + pth->auth.details.basic.username, + len_au); + memcpy (&buf[sizeof (struct BufFormatP) + len_o + len_i + len_b + len_au], + pth->auth.details.basic.password, + len_ap); + break; + } + /* finally give the state back */ + pth->ptc (pth->ptc_cls, + buf, + sizeof (buf)); + } + taler_bank_prepare_wire_transfer_cancel (NULL, + pth); +} + + +/** + * Parse account configuration from @a cfg in @a section into @a account. + * Obtains the URL option and initializes @a account from it. + * + * @param cfg configuration to parse + * @param section section with the account configuration + * @param account[out] account information to initialize + * @return #GNUNET_OK on success + */ +static int +parse_account_cfg (const struct GNUNET_CONFIGURATION_Handle *cfg, + const char *section, + struct Account *account) +{ + char *account_url; + + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_string (cfg, + section, + "URL", + &account_url)) + { + GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, + section, + "URL"); + return GNUNET_SYSERR; + } + + if (TALER_EC_NONE != + parse_payto (account_url, + account)) + { + GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, + section, + "URL", + "Malformed payto:// URL for x-taler-bank method"); + GNUNET_free (account_url); + return GNUNET_SYSERR; + } + GNUNET_free (account_url); + return GNUNET_OK; +} + + +/** + * Prepare for exeuction of a wire transfer. Note that we should call + * @a ptc asynchronously (as that is what the API requires, because + * some transfer methods need it). So while we could immediately call + * @a ptc, we first bundle up all the data and schedule a task to do + * the work. + * + * @param cls the @e cls of this struct with the plugin-specific state + * @param origin_account_section configuration section specifying the origin + * account of the exchange to use + * @param destination_account_url payto:// URL identifying where to send the money + * @param amount amount to transfer, already rounded + * @param exchange_base_url base URL of this exchange + * @param wtid wire transfer identifier to use + * @param ptc function to call with the prepared data to persist + * @param ptc_cls closure for @a ptc + * @return NULL on failure + */ +static struct TALER_WIRE_PrepareHandle * +taler_bank_prepare_wire_transfer (void *cls, + const char *origin_account_section, + const char *destination_account_url, + const struct TALER_Amount *amount, + const char *exchange_base_url, + const struct TALER_WireTransferIdentifierRawP *wtid, + TALER_WIRE_PrepareTransactionCallback ptc, + void *ptc_cls) +{ + struct TalerBankClosure *tc = cls; + struct TALER_WIRE_PrepareHandle *pth; + char *origin_account_url; + struct Account a_in; + struct Account a_out; + + /* Check that payto:// URLs are valid */ + if (TALER_EC_NONE != + parse_payto (destination_account_url, + &a_out)) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "payto://-URL `%s' is invalid!\n", + destination_account_url); + return NULL; + } + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_string (tc->cfg, + origin_account_section, + "URL", + &origin_account_url)) + { + GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, + origin_account_section, + "URL"); + GNUNET_free (a_out.hostname); + return NULL; + } + if (TALER_EC_NONE != + parse_payto (origin_account_url, + &a_in)) + { + GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, + origin_account_section, + "URL", + "Malformed payto:// URL for x-taler-bank method"); + GNUNET_free (origin_account_url); + GNUNET_free (a_out.hostname); + return NULL; + } + + /* Make sure the bank is the same! */ + if (0 != strcasecmp (a_in.hostname, + a_out.hostname)) + { + GNUNET_log (GNUNET_ERROR_TYPE_WARNING, + "x-taler-bank hostname missmatch: `%s' != `%s'\n", + a_in.hostname, + a_out.hostname); + GNUNET_free (a_in.hostname); + GNUNET_free (a_out.hostname); + return NULL; + } + GNUNET_free (a_in.hostname); + GNUNET_free (a_out.hostname); + + pth = GNUNET_new (struct TALER_WIRE_PrepareHandle); + if (GNUNET_OK != + TALER_BANK_auth_parse_cfg (tc->cfg, + origin_account_section, + &pth->auth)) + { + GNUNET_free (pth); + return NULL; + } + + pth->tc = tc; + pth->origin_account_url = origin_account_url; + pth->destination_account_url = GNUNET_strdup (destination_account_url); + pth->exchange_base_url = GNUNET_strdup (exchange_base_url); + pth->wtid = *wtid; + pth->ptc = ptc; + pth->ptc_cls = ptc_cls; + pth->amount = *amount; + pth->task = GNUNET_SCHEDULER_add_now (&do_prepare, + pth); + return pth; +} + + +/** + * Called with the result of submitting information about an incoming + * transaction to a bank. + * + * @param cls closure with the `struct TALER_WIRE_ExecuteHandle` + * @param http_status HTTP response code, #MHD_HTTP_OK (200) for successful status request + * 0 if the bank's reply is bogus (fails to follow the protocol) + * @param ec error code from the bank + * @param serial_id unique ID of the wire transfer in the bank's records; UINT64_MAX on error + * @param json detailed response from the HTTPD, or NULL if reply was not JSON + */ +static void +execute_cb (void *cls, + unsigned int http_status, + enum TALER_ErrorCode ec, + uint64_t serial_id, + const json_t *json) +{ + struct TALER_WIRE_ExecuteHandle *eh = cls; + json_t *reason; + const char *emsg; + char *s; + + eh->aaih = NULL; + emsg = NULL; + if (NULL != json) + { + reason = json_object_get (json, + "reason"); + if (NULL != reason) + emsg = json_string_value (reason); + } + if (NULL != emsg) + GNUNET_asprintf (&s, + "%u/%u (%s)", + http_status, + (unsigned int) ec, + emsg); + else + GNUNET_asprintf (&s, + "%u/%u", + http_status, + (unsigned int) ec); + eh->cc (eh->cc_cls, + (MHD_HTTP_OK == http_status) ? GNUNET_OK : GNUNET_SYSERR, + serial_id, + (MHD_HTTP_OK == http_status) ? NULL : s); + GNUNET_free (s); + GNUNET_free (eh); +} + + +/** + * Execute a wire transfer. + * + * @param cls the @e cls of this struct with the plugin-specific state + * @param buf buffer with the prepared execution details + * @param buf_size number of bytes in @a buf + * @param cc function to call upon success + * @param cc_cls closure for @a cc + * @return NULL on error + */ +static struct TALER_WIRE_ExecuteHandle * +taler_bank_execute_wire_transfer (void *cls, + const char *buf, + size_t buf_size, + TALER_WIRE_ConfirmationCallback cc, + void *cc_cls) +{ + struct TalerBankClosure *tc = cls; + struct TALER_WIRE_ExecuteHandle *eh; + struct TALER_Amount amount; + struct Account origin_account; + struct Account destination_account; + struct BufFormatP bf; + const char *exchange_base_url; + const char *origin_account_url; + const char *destination_account_url; + struct TALER_BANK_AuthenticationData auth; + size_t left; + size_t slen; + char *wire_s; + + if (NULL == tc->ctx) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Bank not initialized, cannot do transfers!\n"); + return NULL; /* not initialized with configuration, cannot do transfers */ + } + if ( (buf_size <= sizeof (struct BufFormatP)) || + ('\0' != buf[buf_size - 1]) ) + { + GNUNET_break (0); + return NULL; + } + memcpy (&bf, + buf, + sizeof (bf)); + TALER_amount_ntoh (&amount, + &bf.amount); + origin_account_url = &buf[sizeof (struct BufFormatP)]; + left = buf_size - sizeof (struct BufFormatP); + slen = strlen (origin_account_url) + 1; + GNUNET_assert (left >= slen); + left -= slen; + if (0 == left) + { + GNUNET_break (0); + return NULL; + } + destination_account_url = &origin_account_url[slen]; + slen = strlen (destination_account_url) + 1; + GNUNET_assert (left >= slen); + left -= slen; + if (0 == left) + { + GNUNET_break (0); + return NULL; + } + exchange_base_url = &destination_account_url[slen]; + slen = strlen (exchange_base_url) + 1; + GNUNET_assert (left >= slen); + left -= slen; + if (0 == left) + { + auth.method = TALER_BANK_AUTH_NONE; + } + else + { + auth.details.basic.username = (char *) &exchange_base_url[slen]; + slen = strlen (auth.details.basic.username) + 1; + GNUNET_assert (left >= slen); + left -= slen; + if (0 == left) + { + GNUNET_break (0); + return NULL; + } + auth.details.basic.password = &auth.details.basic.username[slen]; + slen = strlen (auth.details.basic.username) + 1; + GNUNET_assert (left >= slen); + left -= slen; + if (0 != left) + { + GNUNET_break (0); + return NULL; + } + } + + if (TALER_EC_NONE != + parse_payto (origin_account_url, + &origin_account)) + { + GNUNET_break (0); + return NULL; + } + if (TALER_EC_NONE != + parse_payto (destination_account_url, + &destination_account)) + { + GNUNET_break (0); + return NULL; + } + if (0 != strcasecmp (origin_account.hostname, + destination_account.hostname)) + { + GNUNET_break (0); + return NULL; + } + + eh = GNUNET_new (struct TALER_WIRE_ExecuteHandle); + eh->cc = cc; + eh->cc_cls = cc_cls; + wire_s = GNUNET_STRINGS_data_to_string_alloc (&bf.wtid, + sizeof (bf.wtid)); + eh->aaih = TALER_BANK_admin_add_incoming (tc->ctx, + origin_account.hostname, + &auth, + exchange_base_url, + wire_s, + &amount, + (uint64_t) origin_account.no, + (uint64_t) destination_account.no, + &execute_cb, + eh); + GNUNET_free (wire_s); + if (NULL == eh->aaih) + { + GNUNET_break (0); + GNUNET_free (eh); + return NULL; + } + return eh; +} + + +/** + * Abort execution of a wire transfer. For example, because we are + * shutting down. Note that if an execution is aborted, it may or + * may not still succeed. The caller MUST run @e + * execute_wire_transfer again for the same request as soon as + * possilbe, to ensure that the request either ultimately succeeds + * or ultimately fails. Until this has been done, the transaction is + * in limbo (i.e. may or may not have been committed). + * + * @param cls the @e cls of this struct with the plugin-specific state + * @param eh execution to cancel + */ +static void +taler_bank_execute_wire_transfer_cancel (void *cls, + struct TALER_WIRE_ExecuteHandle *eh) +{ + TALER_BANK_admin_add_incoming_cancel (eh->aaih); + GNUNET_free (eh); +} + + +/** + * Handle for a #taler_bank_get_history() request. + */ +struct TALER_WIRE_HistoryHandle +{ + + /** + * Function to call with results. + */ + TALER_WIRE_HistoryResultCallback hres_cb; + + /** + * Closure for @e hres_cb. + */ + void *hres_cb_cls; + + /** + * Request to the bank. + */ + struct TALER_BANK_HistoryHandle *hh; + + /** + * Authentication to use for access. + */ + struct TALER_BANK_AuthenticationData auth; + +}; + + +/** + * Cancel going over the account's history. + * + * @param cls the @e cls of this struct with the plugin-specific state + * @param whh operation to cancel + */ +static void +taler_bank_get_history_cancel (void *cls, + struct TALER_WIRE_HistoryHandle *whh) +{ + if (NULL != whh->hh) + { + TALER_BANK_history_cancel (whh->hh); + whh->hh = NULL; + } + TALER_BANK_auth_free (&whh->auth); + GNUNET_free (whh); +} + + +/** + * Function called with results from the bank about the transaction history. + * + * @param cls the `struct TALER_WIRE_HistoryHandle` + * @param http_status HTTP response code, #MHD_HTTP_OK (200) for successful status request + * 0 if the bank's reply is bogus (fails to follow the protocol), + * #MHD_HTTP_NO_CONTENT if there are no more results; on success the + * last callback is always of this status (even if `abs(num_results)` were + * already returned). + * @param ec taler error code + * @param dir direction of the transfer + * @param serial_id monotonically increasing counter corresponding to the transaction + * @param details details about the wire transfer + * @param json detailed response from the HTTPD, or NULL if reply was not in JSON + */ +static void +bhist_cb (void *cls, + unsigned int http_status, + enum TALER_ErrorCode ec, + enum TALER_BANK_Direction dir, + uint64_t serial_id, + const struct TALER_BANK_TransferDetails *details, + const json_t *json) +{ + struct TALER_WIRE_HistoryHandle *whh = cls; + uint64_t bserial_id = GNUNET_htonll (serial_id); + struct TALER_WIRE_TransferDetails wd; + + switch (http_status) { + case MHD_HTTP_OK: + { + char *subject; + char *space; + + wd.amount = details->amount; + wd.execution_date = details->execution_date; + subject = GNUNET_strdup (details->wire_transfer_subject); + space = strchr (subject, + (unsigned char) ' '); + if (NULL != space) + { + /* Space separates the actual wire transfer subject from the + exchange base URL (if present, expected only for outgoing + transactions). So we cut the string off at the space. */ + *space = '\0'; + } + /* NOTE: For a real bank, the subject should include a checksum! */ + if (GNUNET_OK != + GNUNET_STRINGS_string_to_data (subject, + strlen (subject), + &wd.wtid, + sizeof (wd.wtid))) + { + /* Ill-formed wire subject, set binary version to all zeros + and pass as a string, this time including the part after + the space. */ + memset (&wd.wtid, + 0, + sizeof (wd.wtid)); + wd.wtid_s = details->wire_transfer_subject; + } + else + { + wd.wtid_s = NULL; + } + GNUNET_free (subject); + wd.account_url = details->account_url; + if ( (NULL != whh->hres_cb) && + (GNUNET_OK != + whh->hres_cb (whh->hres_cb_cls, + TALER_EC_NONE, + dir, + &bserial_id, + sizeof (bserial_id), + &wd)) ) + whh->hres_cb = NULL; + return; /* do NOT yet clean up! */ + } + case MHD_HTTP_NO_CONTENT: + if (NULL != whh->hres_cb) + (void) whh->hres_cb (whh->hres_cb_cls, + ec, + TALER_BANK_DIRECTION_NONE, + NULL, + 0, + NULL); + break; + default: + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Bank failed with HTTP status %u (EC: %u)\n", + http_status, + ec); + if (NULL != whh->hres_cb) + (void) whh->hres_cb (whh->hres_cb_cls, + ec, + TALER_BANK_DIRECTION_NONE, + NULL, + 0, + NULL); + break; + } + whh->hh = NULL; + taler_bank_get_history_cancel (NULL, + whh); +} + + +/** + * Query transfer history of an account. We use the variable-size + * @a start_off to indicate which transfers we are interested in as + * different banking systems may have different ways to identify + * transfers. The @a start_off value must thus match the value of + * a `row_off` argument previously given to the @a hres_cb. Use + * NULL to query transfers from the beginning of time (with + * positive @a num_results) or from the lataler_bank committed transfers + * (with negative @a num_results). + * + * @param cls the @e cls of this struct with the plugin-specific state + * @param account_section specifies the configuration section which + * identifies the account for which we should get the history + * @param direction what kinds of wire transfers should be returned + * @param start_off from which row on do we want to get results, use NULL for the lataler_bank; exclusive + * @param start_off_len number of bytes in @a start_off; must be `sizeof(uint64_t)`. + * @param num_results how many results do we want; negative numbers to go into the past, + * positive numbers to go into the future starting at @a start_row; + * must not be zero. + * @param hres_cb the callback to call with the transaction history + * @param hres_cb_cls closure for the above callback + */ +static struct TALER_WIRE_HistoryHandle * +taler_bank_get_history (void *cls, + const char *account_section, + enum TALER_BANK_Direction direction, + const void *start_off, + size_t start_off_len, + int64_t num_results, + TALER_WIRE_HistoryResultCallback hres_cb, + void *hres_cb_cls) +{ + struct TalerBankClosure *tc = cls; + struct TALER_WIRE_HistoryHandle *whh; + const uint64_t *start_off_b64; + uint64_t start_row; + struct Account account; + + if (0 == num_results) + { + GNUNET_break (0); + return NULL; + } + if (TALER_BANK_DIRECTION_NONE == direction) + { + GNUNET_break (0); + return NULL; + } + if ( (NULL != start_off) && + (sizeof (uint64_t) != start_off_len) ) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Wire plugin 'taler_bank' got start offset of wrong size (%llu instead of %llu)\n", + (unsigned long long) start_off_len, + (unsigned long long) sizeof (uint64_t)); + GNUNET_break (0); + /* Probably something is wrong with the DB, some other component + * wrote a wrong value to it. Instead of completely stopping to work, + * we just scan from the beginning. */ + start_off = NULL; + } + if (NULL == start_off) + { + start_row = UINT64_MAX; /* no start row */ + } + else + { + start_off_b64 = start_off; + start_row = GNUNET_ntohll (*start_off_b64); + } + if (GNUNET_OK != + parse_account_cfg (tc->cfg, + account_section, + &account)) + return NULL; + + whh = GNUNET_new (struct TALER_WIRE_HistoryHandle); + if (GNUNET_OK != + TALER_BANK_auth_parse_cfg (tc->cfg, + account_section, + &whh->auth)) + { + GNUNET_free (whh); + return NULL; + } + + whh->hres_cb = hres_cb; + whh->hres_cb_cls = hres_cb_cls; + whh->hh = TALER_BANK_history (tc->ctx, + account.hostname, + &whh->auth, + (uint64_t) account.no, + direction, + start_row, + num_results, + &bhist_cb, + whh); + if (NULL == whh->hh) + { + GNUNET_break (0); + taler_bank_get_history_cancel (NULL, + whh); + GNUNET_free (account.hostname); + return NULL; + } + GNUNET_free (account.hostname); + return whh; +} + + +/** + * Context for a rejection operation. + */ +struct TALER_WIRE_RejectHandle +{ + /** + * Function to call with the result. + */ + TALER_WIRE_RejectTransferCallback rej_cb; + + /** + * Closure for @e rej_cb. + */ + void *rej_cb_cls; + + /** + * Handle for the reject operation. + */ + struct TALER_BANK_RejectHandle *brh; + + /** + * Authentication information to use. + */ + struct TALER_BANK_AuthenticationData auth; +}; + + +/** + * Callbacks of this type are used to serve the result of asking + * the bank to reject an incoming wire transfer. + * + * @param cls closure + * @param http_status HTTP response code, #MHD_HTTP_NO_CONTENT (204) for successful status request; + * #MHD_HTTP_NOT_FOUND if the rowid is unknown; + * 0 if the bank's reply is bogus (fails to follow the protocol), + * @param ec detailed error code + */ +static void +reject_cb (void *cls, + unsigned int http_status, + enum TALER_ErrorCode ec) +{ + struct TALER_WIRE_RejectHandle *rh = cls; + + rh->brh = NULL; + rh->rej_cb (rh->rej_cb_cls, + ec); + GNUNET_free (rh); +} + + +/** + * Cancel ongoing reject operation. Note that the rejection may still + * proceed. Basically, if this function is called, the rejection may + * have happened or not. This function is usually used during shutdown + * or system upgrades. At a later point, the application must call + * @e reject_transfer again for this wire transfer, unless the + * @e get_history shows that the wire transfer no longer exists. + * + * @param cls plugins' closure + * @param rh operation to cancel + * @return closure of the callback of the operation + */ +static void * +taler_bank_reject_transfer_cancel (void *cls, + struct TALER_WIRE_RejectHandle *rh) +{ + void *ret = rh->rej_cb_cls; + + if (NULL != rh->brh) + TALER_BANK_reject_cancel (rh->brh); + TALER_BANK_auth_free (&rh->auth); + GNUNET_free (rh); + return ret; +} + + +/** + * Reject an incoming wire transfer that was obtained from the + * history. This function can be used to transfer funds back to + * the sender if the WTID was malformed (i.e. due to a typo). + * + * Calling `reject_transfer` twice on the same wire transfer should + * be idempotent, i.e. not cause the funds to be wired back twice. + * Furthermore, the transfer should henceforth be removed from the + * results returned by @e get_history. + * + * @param cls plugin's closure + * @param account_section specifies the configuration section which + * identifies the account to use to reject the transfer + * @param start_off offset of the wire transfer in plugin-specific format + * @param start_off_len number of bytes in @a start_off + * @param rej_cb function to call with the result of the operation + * @param rej_cb_cls closure for @a rej_cb + * @return handle to cancel the operation + */ +static struct TALER_WIRE_RejectHandle * +taler_bank_reject_transfer (void *cls, + const char *account_section, + const void *start_off, + size_t start_off_len, + TALER_WIRE_RejectTransferCallback rej_cb, + void *rej_cb_cls) +{ + struct TalerBankClosure *tc = cls; + const uint64_t *rowid_b64 = start_off; + struct TALER_WIRE_RejectHandle *rh; + struct Account account; + + if (sizeof (uint64_t) != start_off_len) + { + GNUNET_break (0); + return NULL; + } + rh = GNUNET_new (struct TALER_WIRE_RejectHandle); + if (GNUNET_OK != + TALER_BANK_auth_parse_cfg (tc->cfg, + account_section, + &rh->auth)) + { + GNUNET_free (rh); + return NULL; + } + if (GNUNET_OK != + parse_account_cfg (tc->cfg, + account_section, + &account)) + { + (void) taler_bank_reject_transfer_cancel (tc, + rh); + return NULL; + } + rh->rej_cb = rej_cb; + rh->rej_cb_cls = rej_cb_cls; + rh->brh = TALER_BANK_reject (tc->ctx, + account.hostname, + &rh->auth, + (uint64_t) account.no, + GNUNET_ntohll (*rowid_b64), + &reject_cb, + rh); + if (NULL == rh->brh) + { + (void) taler_bank_reject_transfer_cancel (tc, + rh); + GNUNET_free (account.hostname); + return NULL; + } + GNUNET_free (account.hostname); + return rh; +} + + +/** + * Initialize taler_bank-wire subsystem. + * + * @param cls a configuration instance + * @return NULL on error, otherwise a `struct TALER_WIRE_Plugin` + */ +void * +libtaler_plugin_wire_taler_bank_init (void *cls) +{ + struct GNUNET_CONFIGURATION_Handle *cfg = cls; + struct TalerBankClosure *tc; + struct TALER_WIRE_Plugin *plugin; + + tc = GNUNET_new (struct TalerBankClosure); + tc->cfg = cfg; + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_string (cfg, + "taler", + "CURRENCY", + &tc->currency)) + { + GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, + "taler", + "CURRENCY"); + GNUNET_free (tc); + return NULL; + } + tc->ctx = GNUNET_CURL_init (&GNUNET_CURL_gnunet_scheduler_reschedule, + &tc->rc); + tc->rc = GNUNET_CURL_gnunet_rc_create (tc->ctx); + if (NULL == tc->ctx) + { + GNUNET_break (0); + GNUNET_free (tc->currency); + GNUNET_free (tc); + return NULL; + } + plugin = GNUNET_new (struct TALER_WIRE_Plugin); + plugin->cls = tc; + plugin->method = "x-taler-bank"; + plugin->amount_round = &taler_bank_amount_round; + plugin->wire_validate = &taler_bank_wire_validate; + plugin->prepare_wire_transfer = &taler_bank_prepare_wire_transfer; + plugin->prepare_wire_transfer_cancel = &taler_bank_prepare_wire_transfer_cancel; + plugin->execute_wire_transfer = &taler_bank_execute_wire_transfer; + plugin->execute_wire_transfer_cancel = &taler_bank_execute_wire_transfer_cancel; + plugin->get_history = &taler_bank_get_history; + plugin->get_history_cancel = &taler_bank_get_history_cancel; + plugin->reject_transfer = &taler_bank_reject_transfer; + plugin->reject_transfer_cancel = &taler_bank_reject_transfer_cancel; + return plugin; +} + + +/** + * Shutdown taler-bank wire subsystem. + * + * @param cls a `struct TALER_WIRE_Plugin` + * @return NULL (always) + */ +void * +libtaler_plugin_wire_taler_bank_done (void *cls) +{ + struct TALER_WIRE_Plugin *plugin = cls; + struct TalerBankClosure *tc = plugin->cls; + + if (NULL != tc->ctx) + { + GNUNET_CURL_fini (tc->ctx); + tc->ctx = NULL; + } + if (NULL != tc->rc) + { + GNUNET_CURL_gnunet_rc_destroy (tc->rc); + tc->rc = NULL; + } + GNUNET_free_non_null (tc->currency); + GNUNET_free (tc); + GNUNET_free (plugin); + return NULL; +} + +/* end of plugin_wire_taler-bank.c */ |