diff options
Diffstat (limited to 'src/backend/taler-merchant-httpd_post-tips-tip-pickup.c')
| -rw-r--r-- | src/backend/taler-merchant-httpd_post-tips-tip-pickup.c | 771 |
1 files changed, 0 insertions, 771 deletions
diff --git a/src/backend/taler-merchant-httpd_post-tips-tip-pickup.c b/src/backend/taler-merchant-httpd_post-tips-tip-pickup.c deleted file mode 100644 index 51dd8121..00000000 --- a/src/backend/taler-merchant-httpd_post-tips-tip-pickup.c +++ /dev/null @@ -1,771 +0,0 @@ -/* - This file is part of TALER - (C) 2017-2020 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 backend/taler-merchant-httpd_tip-pickup.c - * @brief implementation of /tip-pickup handler - * @author Christian Grothoff - */ -#include "platform.h" -#include <microhttpd.h> -#include <jansson.h> -#include <taler/taler_json_lib.h> -#include <taler/taler_signatures.h> -#include "taler-merchant-httpd.h" -#include "taler-merchant-httpd_mhd.h" -#include "taler-merchant-httpd_exchanges.h" -#include "taler-merchant-httpd_tip-pickup.h" - - -/** - * Information we keep per tip pickup request. - */ -struct PickupContext; - - -/** - * Details about a planchet that the customer wants to obtain - * a withdrawal authorization. This is the information that - * will need to be sent to the exchange to obtain the blind - * signature required to turn a planchet into a coin. - */ -struct PlanchetDetail -{ - - /** - * Hash of the denomination public key requested for this planchet. - */ - struct GNUNET_HashCode h_denom_pub; - - /** - * Pickup context this planchet belongs to. - */ - struct PickupContext *pc; - - /** - * Handle to withdraw operation with the exchange. - */ - struct TALER_EXCHANGE_Withdraw2Handle *wh; - - /** - * Blind signature to return, or NULL if not available. - */ - json_t *blind_sig; - - /** - * Blinded coin (see GNUNET_CRYPTO_rsa_blind()). Note: is malloc()'ed! - */ - char *coin_ev; - - /** - * Number of bytes in @a coin_ev. - */ - size_t coin_ev_size; - -}; - - -/** - * Information we keep per tip pickup request. - */ -struct PickupContext -{ - - /** - * This field MUST be first for handle_mhd_completion_callback() to work - * when it treats this struct as a `struct TM_HandlerContext`. - */ - struct TM_HandlerContext hc; - - /** - * Placeholder for #TALER_MHD_parse_post_json() to keep its internal state. - */ - void *json_parse_context; - - /** - * Kept in a DLL while suspended. - */ - struct PickupContext *next; - - /** - * Kept in a DLL while suspended. - */ - struct PickupContext *prev; - - /** - * URL of the exchange this tip uses. - */ - char *exchange_url; - - /** - * Operation we run to find the exchange (and get its /keys). - */ - struct TMH_EXCHANGES_FindOperation *fo; - - /** - * Handle to the exchange (set after exchange_found_cb()). - */ - struct TALER_EXCHANGE_Handle *eh; - - /** - * Array of planchets of length @e planchets_len. - */ - struct PlanchetDetail *planchets; - - /** - * The connection we are processing. - */ - struct MHD_Connection *connection; - - /** - * Tip ID that was supplied by the client. - */ - struct GNUNET_HashCode tip_id; - - /** - * Unique identifier for the pickup operation, used to detect - * duplicate requests (retries). - */ - struct GNUNET_HashCode pickup_id; - - /** - * Total value of the coins we are withdrawing. - */ - struct TALER_Amount total; - - /** - * Length of @e planchets. - */ - unsigned int planchets_len; - - /** - * Message to return. - */ - struct MHD_Response *response; - - /** - * HTTP status code to return in combination with @e response. - */ - unsigned int response_code; - - /** - * Set to #GNUNET_YES if @e connection was suspended. - */ - int suspended; - -}; - - -/** - * Kept in a DLL while suspended. - */ -static struct PickupContext *pc_head; - -/** - * Kept in a DLL while suspended. - */ -static struct PickupContext *pc_tail; - - -/** - * We are shutting down, force resuming all suspended pickup operations. - */ -void -MH_force_tip_pickup_resume () -{ - struct PickupContext *pc; - - while (NULL != (pc = pc_head)) - { - GNUNET_assert (GNUNET_YES == pc->suspended); - GNUNET_CONTAINER_DLL_remove (pc_head, - pc_tail, - pc); - MHD_resume_connection (pc->connection); - } -} - - -/** - * Custom cleanup routine for a `struct PickupContext`. - * - * @param hc the `struct PickupContext` to clean up. - */ -static void -pickup_cleanup (struct TM_HandlerContext *hc) -{ - struct PickupContext *pc = (struct PickupContext *) hc; - - if (NULL != pc->planchets) - { - for (unsigned int i = 0; i<pc->planchets_len; i++) - { - struct PlanchetDetail *pd = &pc->planchets[i]; - GNUNET_free_non_null (pd->coin_ev); - if (NULL != pd->wh) - { - TALER_EXCHANGE_withdraw2_cancel (pd->wh); - pd->wh = NULL; - } - if (NULL != pd->blind_sig) - { - json_decref (pd->blind_sig); - pd->blind_sig = NULL; - } - } - GNUNET_free (pc->planchets); - pc->planchets = NULL; - } - if (NULL != pc->fo) - { - TMH_EXCHANGES_find_exchange_cancel (pc->fo); - pc->fo = NULL; - } - TALER_MHD_parse_post_cleanup_callback (pc->json_parse_context); - GNUNET_free_non_null (pc->exchange_url); - if (NULL != pc->response) - { - MHD_destroy_response (pc->response); - pc->response = NULL; - } - GNUNET_free (pc); -} - - -/** - * Resume processing of a suspended @a pc. - * - * @param pc a suspended pickup operation - */ -static void -resume_pc (struct PickupContext *pc) -{ - for (unsigned int i = 0; i<pc->planchets_len; i++) - { - struct PlanchetDetail *pd = &pc->planchets[i]; - - if (NULL != pd->wh) - { - TALER_EXCHANGE_withdraw2_cancel (pc->planchets[i].wh); - pc->planchets[i].wh = NULL; - } - } - GNUNET_assert (GNUNET_YES == pc->suspended); - GNUNET_CONTAINER_DLL_remove (pc_head, - pc_tail, - pc); - MHD_resume_connection (pc->connection); - TMH_trigger_daemon (); -} - - -/** - * Function called with the result of our attempt to withdraw - * the coin for a tip. - * - * @param cls closure - * @param hr HTTP response data - * @param blind_sig blind signature over the coin, NULL on error - */ -static void -withdraw_cb (void *cls, - const struct TALER_EXCHANGE_HttpResponse *hr, - const struct GNUNET_CRYPTO_RsaSignature *blind_sig) -{ - struct PlanchetDetail *pd = cls; - struct PickupContext *pc = pd->pc; - json_t *ja; - - pd->wh = NULL; - if (NULL == blind_sig) - { - pc->response_code = MHD_HTTP_FAILED_DEPENDENCY; - pc->response = TALER_MHD_make_json_pack ( - (NULL != hr->reply) - ? "{s:s, s:I, s:I, s:I, s:O}" - : "{s:s, s:I, s:I, s:I}", - "hint", "failed to withdraw coin from exchange", - "code", (json_int_t) TALER_EC_TIP_PICKUP_WITHDRAW_FAILED_AT_EXCHANGE, - "exchange_http_status", (json_int_t) hr->http_status, - "exchange_code", (json_int_t) hr->ec, - "exchange_reply", hr->reply); - resume_pc (pc); - return; - } - /* FIXME: persisit blind_sig in our database!? - (or at least _all_ of them once we have them all?) */ - pd->blind_sig = GNUNET_JSON_from_rsa_signature (blind_sig); - GNUNET_assert (NULL != pd->blind_sig); - for (unsigned int i = 0; i<pc->planchets_len; i++) - if (NULL != pc->planchets[i].wh) - return; - /* All done, build final response */ - ja = json_array (); - GNUNET_assert (NULL != ja); - for (unsigned int i = 0; i<pc->planchets_len; i++) - { - struct PlanchetDetail *pd = &pc->planchets[i]; - - GNUNET_assert (0 == - json_array_append_new (ja, - json_pack ("{s:o}", - "blind_sig", - pd->blind_sig))); - pd->blind_sig = NULL; - } - pc->response_code = MHD_HTTP_OK; - pc->response = TALER_MHD_make_json_pack ("{s:o}", - "blind_sigs", - ja); - resume_pc (pc); -} - - -/** - * Prepare (and eventually execute) a pickup. Computes - * the "pickup ID" (by hashing the planchets and denomination keys), - * resolves the denomination keys and calculates the total - * amount to be picked up. Then runs the pick up execution logic. - * - * @param pc pickup context - */ -static void -run_pickup (struct PickupContext *pc) -{ - struct TALER_ReservePrivateKeyP reserve_priv; - enum TALER_ErrorCode ec; - - db->preflight (db->cls); - ec = db->pickup_tip_TR (db->cls, - &pc->total, - &pc->tip_id, - &pc->pickup_id, - &reserve_priv); - if (TALER_EC_NONE != ec) - { - const char *human; - - switch (ec) - { - case TALER_EC_TIP_PICKUP_TIP_ID_UNKNOWN: - pc->response_code = MHD_HTTP_NOT_FOUND; - human = "tip identifier not known to this service"; - break; - case TALER_EC_TIP_PICKUP_NO_FUNDS: - pc->response_code = MHD_HTTP_CONFLICT; - human = "withdrawn funds exceed amounts approved for tip"; - break; - default: - pc->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR; - human = "database failure"; - break; - } - pc->response = TALER_MHD_make_error (ec, - human); - resume_pc (pc); - return; - } - for (unsigned int i = 0; i<pc->planchets_len; i++) - { - struct PlanchetDetail *pd = &pc->planchets[i]; - struct TALER_PlanchetDetail pdx = { - .denom_pub_hash = pd->h_denom_pub, - .coin_ev = pd->coin_ev, - .coin_ev_size = pd->coin_ev_size, - }; - - pd->wh = TALER_EXCHANGE_withdraw2 (pc->eh, - &pdx, - &reserve_priv, - &withdraw_cb, - pd); - if (NULL == pd->wh) - { - GNUNET_break (0); - pc->response_code = MHD_HTTP_INTERNAL_SERVER_ERROR; - pc->response = TALER_MHD_make_error (TALER_EC_TIP_PICKUP_WITHDRAW_FAILED, - "could not inititate withdrawal"); - resume_pc (pc); - return; - } - } -} - - -/** - * Function called with the result of a #TMH_EXCHANGES_find_exchange() - * operation. - * - * @param cls closure with the `struct PickupContext` - * @param hr HTTP response details - * @param eh handle to the exchange context - * @param wire_fee current applicable wire fee for dealing with @a eh, NULL if not available - * @param exchange_trusted #GNUNET_YES if this exchange is trusted by config - */ -static void -exchange_found_cb (void *cls, - const struct TALER_EXCHANGE_HttpResponse *hr, - struct TALER_EXCHANGE_Handle *eh, - const struct TALER_Amount *wire_fee, - int exchange_trusted) -{ - struct PickupContext *pc = cls; - const struct TALER_EXCHANGE_Keys *keys; - struct TALER_Amount total; - int ae; - - pc->fo = NULL; - if (NULL == eh) - { - pc->response_code = MHD_HTTP_FAILED_DEPENDENCY; - pc->response = TALER_MHD_make_json_pack ( - (NULL != hr->reply) - ? "{s:s, s:I, s:I, s:I, s:O}" - : "{s:s, s:I, s:I, s:I}", - "hint", "failed to contact exchange, check URL", - "code", (json_int_t) TALER_EC_TIP_PICKUP_EXCHANGE_DOWN, - "exchange_http_status", (json_int_t) hr->http_status, - "exchange_code", (json_int_t) hr->ec, - "exchange_reply", hr->reply); - resume_pc (pc); - return; - } - keys = TALER_EXCHANGE_get_keys (eh); - if (NULL == keys) - { - pc->response_code = MHD_HTTP_FAILED_DEPENDENCY; - pc->response = TALER_MHD_make_json_pack ( - (NULL != hr->reply) - ? "{s:s, s:I, s:I, s:I, s:O}" - : "{s:s, s:I, s:I, s:I}", - "hint", "could not obtain denomination keys from exchange, check URL", - "code", (json_int_t) TALER_EC_TIP_PICKUP_EXCHANGE_LACKED_KEYS, - "exchange_http_status", (json_int_t) hr->http_status, - "exchange_code", (json_int_t) hr->ec, - "exchange_reply", hr->reply); - resume_pc (pc); - return; - } - GNUNET_assert (0 != pc->planchets_len); - ae = GNUNET_NO; - memset (&total, - 0, - sizeof (total)); - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Calculating tip amount over %u planchets!\n", - pc->planchets_len); - { - struct GNUNET_HashContext *hc; - - hc = GNUNET_CRYPTO_hash_context_start (); - for (unsigned int i = 0; i<pc->planchets_len; i++) - { - struct PlanchetDetail *pd = &pc->planchets[i]; - struct TALER_Amount amount_with_fee; - const struct TALER_EXCHANGE_DenomPublicKey *dk; - - dk = TALER_EXCHANGE_get_denomination_key_by_hash (keys, - &pd->h_denom_pub); - if (NULL == dk) - { - pc->response_code = MHD_HTTP_NOT_FOUND; - pc->response - = TALER_MHD_make_json_pack ( - "{s:s, s:I}" - "hint", - "could not find matching denomination key", - "code", - (json_int_t) TALER_EC_TIP_PICKUP_EXCHANGE_LACKED_KEY); - resume_pc (pc); - GNUNET_CRYPTO_hash_context_abort (hc); - return; - } - GNUNET_CRYPTO_hash_context_read (hc, - &pd->h_denom_pub, - sizeof (struct GNUNET_HashCode)); - GNUNET_CRYPTO_hash_context_read (hc, - pd->coin_ev, - pd->coin_ev_size); - if (0 > - TALER_amount_add (&amount_with_fee, - &dk->value, - &dk->fee_withdraw)) - { - ae = GNUNET_YES; - } - if (0 == i) - { - total = amount_with_fee; - } - else - { - if (0 > - TALER_amount_add (&total, - &total, - &amount_with_fee)) - { - ae = GNUNET_YES; - } - } - } - GNUNET_CRYPTO_hash_context_finish (hc, - &pc->pickup_id); - } - if (GNUNET_YES == ae) - { - pc->response_code = MHD_HTTP_BAD_REQUEST; - pc->response - = TALER_MHD_make_json_pack ( - "{s:s, s:I}" - "hint", - "error computing total value of the tip", - "code", - (json_int_t) TALER_EC_TIP_PICKUP_EXCHANGE_AMOUNT_OVERFLOW); - resume_pc (pc); - return; - } - pc->eh = eh; - pc->total = total; - run_pickup (pc); -} - - -/** - * Prepare (and eventually execute) a pickup. Finds the exchange - * handle we need for #run_pickup(). - * - * @param pc pickup context - * @return #MHD_YES upon success, #MHD_NO if - * the connection ought to be dropped - */ -static MHD_RESULT -prepare_pickup (struct PickupContext *pc) -{ - enum GNUNET_DB_QueryStatus qs; - - db->preflight (db->cls); - /* FIXME: do not pass NULL's, *do* get the - data from the DB, we may be able to avoid - most of the processing if we already have - a valid result! */ - qs = db->lookup_tip_by_id (db->cls, - &pc->tip_id, - &pc->exchange_url, - NULL, NULL, NULL, NULL); - if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT != qs) - { - unsigned int response_code; - enum TALER_ErrorCode ec; - - switch (qs) - { - case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS: - ec = TALER_EC_TIP_PICKUP_TIP_ID_UNKNOWN; - response_code = MHD_HTTP_NOT_FOUND; - break; - case GNUNET_DB_STATUS_SOFT_ERROR: - ec = TALER_EC_TIP_PICKUP_DB_ERROR_SOFT; - response_code = MHD_HTTP_INTERNAL_SERVER_ERROR; - break; - case GNUNET_DB_STATUS_HARD_ERROR: - ec = TALER_EC_TIP_PICKUP_DB_ERROR_HARD; - response_code = MHD_HTTP_INTERNAL_SERVER_ERROR; - break; - default: - GNUNET_break (0); - ec = TALER_EC_INTERNAL_LOGIC_ERROR; - response_code = MHD_HTTP_INTERNAL_SERVER_ERROR; - break; - } - return TALER_MHD_reply_with_error (pc->connection, - response_code, - ec, - "Could not determine exchange URL for the given tip id"); - - } - pc->fo = TMH_EXCHANGES_find_exchange (pc->exchange_url, - NULL, - GNUNET_NO, - &exchange_found_cb, - pc); - if (NULL == pc->fo) - { - return TALER_MHD_reply_with_error (pc->connection, - MHD_HTTP_INTERNAL_SERVER_ERROR, - TALER_EC_INTERNAL_INVARIANT_FAILURE, - "consult server logs"); - } - /* continued asynchronously in exchange_found_cb() */ - GNUNET_assert (GNUNET_NO == pc->suspended); - pc->suspended = GNUNET_YES; - GNUNET_CONTAINER_DLL_insert (pc_head, - pc_tail, - pc); - MHD_suspend_connection (pc->connection); - return MHD_YES; -} - - -/** - * Parse the given @a planchet into the @a pd. - * - * @param connection connection to use for error reporting - * @param planchet planchet data in JSON format - * @param[out] pd where to store the binary data - * @return #GNUNET_OK upon success, #GNUNET_NO if a response - * was generated, #GNUNET_SYSERR to drop the connection - */ -static enum GNUNET_GenericReturnValue -parse_planchet (struct MHD_Connection *connection, - const json_t *planchet, - struct PlanchetDetail *pd) -{ - struct GNUNET_JSON_Specification spec[] = { - GNUNET_JSON_spec_fixed_auto ("denom_pub_hash", - &pd->h_denom_pub), - GNUNET_JSON_spec_varsize ("coin_ev", - (void **) &pd->coin_ev, - &pd->coin_ev_size), - GNUNET_JSON_spec_end () - }; - - return TALER_MHD_parse_json_data (connection, - planchet, - spec); -} - - -/** - * Manages a POST /tip-pickup call, checking that the tip is authorized, - * and if so, returning the withdrawal permissions. - * - * @param rh context of the handler - * @param connection the MHD connection to handle - * @param[in,out] connection_cls the connection's closure (can be updated) - * @param upload_data upload data - * @param[in,out] upload_data_size number of bytes (left) in @a upload_data - * @param mi merchant backend instance, never NULL - * @return MHD result code - */ -MHD_RESULT -MH_handler_tip_pickup (struct TMH_RequestHandler *rh, - struct MHD_Connection *connection, - void **connection_cls, - const char *upload_data, - size_t *upload_data_size, - struct MerchantInstance *mi) -{ - enum GNUNET_GenericReturnValue res; - struct GNUNET_HashCode tip_id; - json_t *planchets; - struct GNUNET_JSON_Specification spec[] = { - GNUNET_JSON_spec_fixed_auto ("tip_id", - &tip_id), - GNUNET_JSON_spec_json ("planchets", - &planchets), - GNUNET_JSON_spec_end () - }; - struct PickupContext *pc; - json_t *root; - - if (NULL == *connection_cls) - { - pc = GNUNET_new (struct PickupContext); - pc->hc.cc = &pickup_cleanup; - pc->connection = connection; - *connection_cls = pc; - } - else - { - pc = *connection_cls; - } - if (NULL != pc->response) - { - MHD_RESULT ret; - - ret = MHD_queue_response (connection, - pc->response_code, - pc->response); - MHD_destroy_response (pc->response); - pc->response = NULL; - return ret; - } - res = TALER_MHD_parse_post_json (connection, - &pc->json_parse_context, - upload_data, - upload_data_size, - &root); - if (GNUNET_SYSERR == res) - return MHD_NO; - /* the POST's body has to be further fetched */ - if ( (GNUNET_NO == res) || - (NULL == root) ) - return MHD_YES; - - res = TALER_MHD_parse_json_data (connection, - root, - spec); - if (GNUNET_YES != res) - { - GNUNET_break_op (0); - json_decref (root); - return (GNUNET_NO == res) ? MHD_YES : MHD_NO; - } - pc->planchets_len = json_array_size (planchets); - if (pc->planchets_len > 1024) - { - GNUNET_JSON_parse_free (spec); - json_decref (root); - return TALER_MHD_reply_with_error (connection, - MHD_HTTP_BAD_REQUEST, - TALER_EC_TIP_PICKUP_EXCHANGE_TOO_MANY_PLANCHETS, - "per request limit of 1024 planchets exceeded"); - } - if (0 == pc->planchets_len) - { - GNUNET_JSON_parse_free (spec); - json_decref (root); - return TALER_MHD_reply_with_error (connection, - MHD_HTTP_BAD_REQUEST, - TALER_EC_PARAMETER_MALFORMED, - "no planchets specified"); - } - db->preflight (db->cls); - pc->planchets = GNUNET_new_array (pc->planchets_len, - struct PlanchetDetail); - for (unsigned int i = 0; i<pc->planchets_len; i++) - { - pc->planchets[i].pc = pc; - if (GNUNET_OK != - (res = parse_planchet (connection, - json_array_get (planchets, - i), - &pc->planchets[i]))) - { - GNUNET_JSON_parse_free (spec); - json_decref (root); - return (GNUNET_NO == res) ? MHD_YES : MHD_NO; - } - } - pc->tip_id = tip_id; - { - MHD_RESULT ret; - - ret = prepare_pickup (pc); - GNUNET_JSON_parse_free (spec); - json_decref (root); - return ret; - } -} |