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Diffstat (limited to 'src/lib/exchange_api_track_transaction.c')
| -rw-r--r-- | src/lib/exchange_api_track_transaction.c | 367 |
1 files changed, 367 insertions, 0 deletions
diff --git a/src/lib/exchange_api_track_transaction.c b/src/lib/exchange_api_track_transaction.c new file mode 100644 index 000000000..0942ce84a --- /dev/null +++ b/src/lib/exchange_api_track_transaction.c @@ -0,0 +1,367 @@ +/* + This file is part of TALER + Copyright (C) 2014, 2015, 2016 GNUnet e.V. + + 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 exchange-lib/exchange_api_track_transaction.c + * @brief Implementation of the /track/transaction request of the exchange's HTTP API + * @author Christian Grothoff + */ +#include "platform.h" +#include <jansson.h> +#include <microhttpd.h> /* just for HTTP status codes */ +#include <gnunet/gnunet_util_lib.h> +#include <gnunet/gnunet_json_lib.h> +#include <gnunet/gnunet_curl_lib.h> +#include "taler_json_lib.h" +#include "taler_exchange_service.h" +#include "exchange_api_handle.h" +#include "taler_signatures.h" +#include "exchange_api_curl_defaults.h" + + +/** + * @brief A Deposit Wtid Handle + */ +struct TALER_EXCHANGE_TrackTransactionHandle +{ + + /** + * The connection to exchange this request handle will use + */ + struct TALER_EXCHANGE_Handle *exchange; + + /** + * The url for this request. + */ + char *url; + + /** + * JSON encoding of the request to POST. + */ + char *json_enc; + + /** + * Handle for the request. + */ + struct GNUNET_CURL_Job *job; + + /** + * Function to call with the result. + */ + TALER_EXCHANGE_TrackTransactionCallback cb; + + /** + * Closure for @a cb. + */ + void *cb_cls; + + /** + * Information the exchange should sign in response. + * (with pre-filled fields from the request). + */ + struct TALER_ConfirmWirePS depconf; + +}; + + +/** + * Verify that the signature on the "200 OK" response + * from the exchange is valid. + * + * @param dwh deposit wtid handle + * @param json json reply with the signature + * @param[out] exchange_pub set to the exchange's public key + * @return #GNUNET_OK if the signature is valid, #GNUNET_SYSERR if not + */ +static int +verify_deposit_wtid_signature_ok (const struct TALER_EXCHANGE_TrackTransactionHandle *dwh, + const json_t *json, + struct TALER_ExchangePublicKeyP *exchange_pub) +{ + struct TALER_ExchangeSignatureP exchange_sig; + const struct TALER_EXCHANGE_Keys *key_state; + struct GNUNET_JSON_Specification spec[] = { + GNUNET_JSON_spec_fixed_auto ("exchange_sig", &exchange_sig), + GNUNET_JSON_spec_fixed_auto ("exchange_pub", exchange_pub), + GNUNET_JSON_spec_end() + }; + + if (GNUNET_OK != + GNUNET_JSON_parse (json, + spec, + NULL, NULL)) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + key_state = TALER_EXCHANGE_get_keys (dwh->exchange); + if (GNUNET_OK != + TALER_EXCHANGE_test_signing_key (key_state, + exchange_pub)) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_OK != + GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_EXCHANGE_CONFIRM_WIRE, + &dwh->depconf.purpose, + &exchange_sig.eddsa_signature, + &exchange_pub->eddsa_pub)) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + return GNUNET_OK; +} + + +/** + * Function called when we're done processing the + * HTTP /track/transaction request. + * + * @param cls the `struct TALER_EXCHANGE_TrackTransactionHandle` + * @param response_code HTTP response code, 0 on error + * @param response parsed JSON result, NULL on error + */ +static void +handle_deposit_wtid_finished (void *cls, + long response_code, + const void *response) +{ + struct TALER_EXCHANGE_TrackTransactionHandle *dwh = cls; + const struct TALER_WireTransferIdentifierRawP *wtid = NULL; + struct GNUNET_TIME_Absolute execution_time = GNUNET_TIME_UNIT_FOREVER_ABS; + const struct TALER_Amount *coin_contribution = NULL; + struct TALER_Amount coin_contribution_s; + struct TALER_ExchangePublicKeyP exchange_pub; + struct TALER_ExchangePublicKeyP *ep = NULL; + const json_t *j = response; + + dwh->job = NULL; + switch (response_code) + { + case 0: + break; + case MHD_HTTP_OK: + { + struct GNUNET_JSON_Specification spec[] = { + GNUNET_JSON_spec_fixed_auto ("wtid", &dwh->depconf.wtid), + GNUNET_JSON_spec_absolute_time ("execution_time", &execution_time), + TALER_JSON_spec_amount ("coin_contribution", &coin_contribution_s), + GNUNET_JSON_spec_end() + }; + + if (GNUNET_OK != + GNUNET_JSON_parse (j, + spec, + NULL, NULL)) + { + GNUNET_break_op (0); + response_code = 0; + break; + } + wtid = &dwh->depconf.wtid; + dwh->depconf.execution_time = GNUNET_TIME_absolute_hton (execution_time); + TALER_amount_hton (&dwh->depconf.coin_contribution, + &coin_contribution_s); + coin_contribution = &coin_contribution_s; + if (GNUNET_OK != + verify_deposit_wtid_signature_ok (dwh, + j, + &exchange_pub)) + { + GNUNET_break_op (0); + response_code = 0; + } + else + { + ep = &exchange_pub; + } + } + break; + case MHD_HTTP_ACCEPTED: + { + /* Transaction known, but not executed yet */ + struct GNUNET_JSON_Specification spec[] = { + GNUNET_JSON_spec_absolute_time ("execution_time", &execution_time), + GNUNET_JSON_spec_end() + }; + + if (GNUNET_OK != + GNUNET_JSON_parse (j, + spec, + NULL, NULL)) + { + GNUNET_break_op (0); + response_code = 0; + break; + } + } + break; + case MHD_HTTP_BAD_REQUEST: + /* This should never happen, either us or the exchange is buggy + (or API version conflict); just pass JSON reply to the application */ + break; + case MHD_HTTP_UNAUTHORIZED: + /* Nothing really to verify, exchange says one of the signatures is + invalid; as we checked them, this should never happen, we + should pass the JSON reply to the application */ + break; + case MHD_HTTP_NOT_FOUND: + /* Exchange does not know about transaction; + we should pass the reply to the application */ + break; + case MHD_HTTP_INTERNAL_SERVER_ERROR: + /* Server had an internal issue; we should retry, but this API + leaves this to the application */ + break; + default: + /* unexpected response code */ + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Unexpected response code %u\n", + (unsigned int) response_code); + GNUNET_break (0); + response_code = 0; + break; + } + dwh->cb (dwh->cb_cls, + response_code, + TALER_JSON_get_error_code (j), + ep, + j, + wtid, + execution_time, + coin_contribution); + TALER_EXCHANGE_track_transaction_cancel (dwh); +} + + +/** + * Obtain wire transfer details about an existing deposit operation. + * + * @param exchange the exchange to query + * @param merchant_priv the merchant's private key + * @param h_wire hash of merchant's wire transfer details + * @param h_contract_terms hash of the proposal data from the contract + * between merchant and customer + * @param coin_pub public key of the coin + * @param cb function to call with the result + * @param cb_cls closure for @a cb + * @return handle to abort request + */ +struct TALER_EXCHANGE_TrackTransactionHandle * +TALER_EXCHANGE_track_transaction (struct TALER_EXCHANGE_Handle *exchange, + const struct TALER_MerchantPrivateKeyP *merchant_priv, + const struct GNUNET_HashCode *h_wire, + const struct GNUNET_HashCode *h_contract_terms, + const struct TALER_CoinSpendPublicKeyP *coin_pub, + TALER_EXCHANGE_TrackTransactionCallback cb, + void *cb_cls) +{ + struct TALER_DepositTrackPS dtp; + struct TALER_MerchantSignatureP merchant_sig; + struct TALER_EXCHANGE_TrackTransactionHandle *dwh; + struct GNUNET_CURL_Context *ctx; + json_t *deposit_wtid_obj; + CURL *eh; + + if (GNUNET_YES != + TEAH_handle_is_ready (exchange)) + { + GNUNET_break (0); + return NULL; + } + dtp.purpose.purpose = htonl (TALER_SIGNATURE_MERCHANT_TRACK_TRANSACTION); + dtp.purpose.size = htonl (sizeof (dtp)); + dtp.h_contract_terms = *h_contract_terms; + dtp.h_wire = *h_wire; + GNUNET_CRYPTO_eddsa_key_get_public (&merchant_priv->eddsa_priv, + &dtp.merchant.eddsa_pub); + + dtp.coin_pub = *coin_pub; + GNUNET_assert (GNUNET_OK == + GNUNET_CRYPTO_eddsa_sign (&merchant_priv->eddsa_priv, + &dtp.purpose, + &merchant_sig.eddsa_sig)); + deposit_wtid_obj = json_pack ("{s:o, s:o," /* H_wire, h_contract_terms */ + " s:o," /* coin_pub */ + " s:o, s:o}", /* merchant_pub, merchant_sig */ + "H_wire", GNUNET_JSON_from_data_auto (h_wire), + "h_contract_terms", GNUNET_JSON_from_data_auto (h_contract_terms), + "coin_pub", GNUNET_JSON_from_data_auto (coin_pub), + "merchant_pub", GNUNET_JSON_from_data_auto (&dtp.merchant), + "merchant_sig", GNUNET_JSON_from_data_auto (&merchant_sig)); + if (NULL == deposit_wtid_obj) + { + GNUNET_break (0); + return NULL; + } + + dwh = GNUNET_new (struct TALER_EXCHANGE_TrackTransactionHandle); + dwh->exchange = exchange; + dwh->cb = cb; + dwh->cb_cls = cb_cls; + dwh->url = TEAH_path_to_url (exchange, "/track/transaction"); + dwh->depconf.purpose.size = htonl (sizeof (struct TALER_ConfirmWirePS)); + dwh->depconf.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_WIRE); + dwh->depconf.h_wire = *h_wire; + dwh->depconf.h_contract_terms = *h_contract_terms; + dwh->depconf.coin_pub = *coin_pub; + + eh = TEL_curl_easy_get (dwh->url); + GNUNET_assert (NULL != (dwh->json_enc = + json_dumps (deposit_wtid_obj, + JSON_COMPACT))); + json_decref (deposit_wtid_obj); + GNUNET_assert (CURLE_OK == + curl_easy_setopt (eh, + CURLOPT_POSTFIELDS, + dwh->json_enc)); + GNUNET_assert (CURLE_OK == + curl_easy_setopt (eh, + CURLOPT_POSTFIELDSIZE, + strlen (dwh->json_enc))); + ctx = TEAH_handle_to_context (exchange); + dwh->job = GNUNET_CURL_job_add (ctx, + eh, + GNUNET_YES, + &handle_deposit_wtid_finished, + dwh); + return dwh; +} + + +/** + * Cancel deposit wtid request. This function cannot be used on a request + * handle if a response is already served for it. + * + * @param dwh the wire deposits request handle + */ +void +TALER_EXCHANGE_track_transaction_cancel (struct TALER_EXCHANGE_TrackTransactionHandle *dwh) +{ + if (NULL != dwh->job) + { + GNUNET_CURL_job_cancel (dwh->job); + dwh->job = NULL; + } + GNUNET_free (dwh->url); + GNUNET_free (dwh->json_enc); + GNUNET_free (dwh); +} + + +/* end of exchange_api_deposit_wtid.c */ |