/*
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
*/
/**
* @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
/* only for HTTP status codes */
#include
/**
* 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.method = TALER_BANK_AUTH_BASIC;
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.password) + 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;
GNUNET_break (NULL != whh->hh);
/* Once we get the sentinel element, the handle becomes invalid. */
if (TALER_BANK_DIRECTION_NONE == dir)
whh->hh = NULL;
return;
}
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;
char *bank_base_url;
char *p;
long long unsigned port;
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;
port = 433; /* if non given, equals 433. */
if (NULL != (p = strchr (account.hostname,
(unsigned char) ':')))
{
p++;
if (1 != sscanf (p,
"%llu",
&port))
{
GNUNET_break (0);
TALER_LOG_ERROR ("Malformed host from payto:// URI\n");
return NULL;
}
}
if (443 != port)
{
GNUNET_assert
(GNUNET_SYSERR != GNUNET_asprintf
(&bank_base_url,
"http://%s",
account.hostname));
}
else
{
GNUNET_assert
(GNUNET_SYSERR != GNUNET_asprintf
(&bank_base_url,
"https://%s",
account.hostname));
}
whh->hh = TALER_BANK_history (tc->ctx,
bank_base_url,
&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 */