diff options
Diffstat (limited to 'src/lib/exchange_api_contracts_get.c')
| -rw-r--r-- | src/lib/exchange_api_contracts_get.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/src/lib/exchange_api_contracts_get.c b/src/lib/exchange_api_contracts_get.c new file mode 100644 index 000000000..aece7733a --- /dev/null +++ b/src/lib/exchange_api_contracts_get.c @@ -0,0 +1,262 @@ +/* + This file is part of TALER + Copyright (C) 2022 Taler Systems SA + + TALER is free software; you can redistribute it and/or modify it under the + terms of the GNU 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 lib/exchange_api_contracts_get.c + * @brief Implementation of the /contracts/ GET request + * @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 Contract Get Handle + */ +struct TALER_EXCHANGE_ContractsGetHandle +{ + + /** + * The url for this request. + */ + char *url; + + /** + * Handle for the request. + */ + struct GNUNET_CURL_Job *job; + + /** + * Function to call with the result. + */ + TALER_EXCHANGE_ContractGetCallback cb; + + /** + * Closure for @a cb. + */ + void *cb_cls; + + /** + * Private key needed to decrypt the contract. + */ + struct TALER_ContractDiffiePrivateP contract_priv; + + /** + * Public key matching @e contract_priv. + */ + struct TALER_ContractDiffiePublicP cpub; + +}; + + +/** + * Function called when we're done processing the + * HTTP /track/transaction request. + * + * @param cls the `struct TALER_EXCHANGE_ContractsGetHandle` + * @param response_code HTTP response code, 0 on error + * @param response parsed JSON result, NULL on error + */ +static void +handle_contract_get_finished (void *cls, + long response_code, + const void *response) +{ + struct TALER_EXCHANGE_ContractsGetHandle *cgh = cls; + const json_t *j = response; + struct TALER_EXCHANGE_ContractGetResponse dr = { + .hr.reply = j, + .hr.http_status = (unsigned int) response_code + }; + + cgh->job = NULL; + switch (response_code) + { + case 0: + dr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE; + break; + case MHD_HTTP_OK: + { + void *econtract; + size_t econtract_size; + struct TALER_PurseContractSignatureP econtract_sig; + struct GNUNET_JSON_Specification spec[] = { + GNUNET_JSON_spec_fixed_auto ("purse_pub", + &dr.details.ok.purse_pub), + GNUNET_JSON_spec_fixed_auto ("econtract_sig", + &econtract_sig), + GNUNET_JSON_spec_varsize ("econtract", + &econtract, + &econtract_size), + GNUNET_JSON_spec_end () + }; + + if (GNUNET_OK != + GNUNET_JSON_parse (j, + spec, + NULL, NULL)) + { + GNUNET_break_op (0); + dr.hr.http_status = 0; + dr.hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED; + break; + } + if (GNUNET_OK != + TALER_wallet_econtract_upload_verify ( + econtract, + econtract_size, + &cgh->cpub, + &dr.details.ok.purse_pub, + &econtract_sig)) + { + GNUNET_break (0); + dr.hr.http_status = 0; + dr.hr.ec = TALER_EC_EXCHANGE_CONTRACTS_SIGNATURE_INVALID; + GNUNET_JSON_parse_free (spec); + break; + } + dr.details.ok.econtract = econtract; + dr.details.ok.econtract_size = econtract_size; + cgh->cb (cgh->cb_cls, + &dr); + GNUNET_JSON_parse_free (spec); + TALER_EXCHANGE_contract_get_cancel (cgh); + return; + } + case MHD_HTTP_BAD_REQUEST: + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + /* 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_FORBIDDEN: + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + /* 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: + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + /* Exchange does not know about transaction; + we should pass the reply to the application */ + break; + case MHD_HTTP_INTERNAL_SERVER_ERROR: + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + /* Server had an internal issue; we should retry, but this API + leaves this to the application */ + break; + default: + /* unexpected response code */ + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Unexpected response code %u/%d for exchange GET contracts\n", + (unsigned int) response_code, + (int) dr.hr.ec); + GNUNET_break_op (0); + break; + } + cgh->cb (cgh->cb_cls, + &dr); + TALER_EXCHANGE_contract_get_cancel (cgh); +} + + +struct TALER_EXCHANGE_ContractsGetHandle * +TALER_EXCHANGE_contract_get ( + struct GNUNET_CURL_Context *ctx, + const char *url, + const struct TALER_ContractDiffiePrivateP *contract_priv, + TALER_EXCHANGE_ContractGetCallback cb, + void *cb_cls) +{ + struct TALER_EXCHANGE_ContractsGetHandle *cgh; + CURL *eh; + char arg_str[sizeof (cgh->cpub) * 2 + 48]; + + cgh = GNUNET_new (struct TALER_EXCHANGE_ContractsGetHandle); + cgh->cb = cb; + cgh->cb_cls = cb_cls; + GNUNET_CRYPTO_ecdhe_key_get_public (&contract_priv->ecdhe_priv, + &cgh->cpub.ecdhe_pub); + { + char cpub_str[sizeof (cgh->cpub) * 2]; + char *end; + + end = GNUNET_STRINGS_data_to_string (&cgh->cpub, + sizeof (cgh->cpub), + cpub_str, + sizeof (cpub_str)); + *end = '\0'; + GNUNET_snprintf (arg_str, + sizeof (arg_str), + "contracts/%s", + cpub_str); + } + + cgh->url = TALER_url_join (url, + arg_str, + NULL); + if (NULL == cgh->url) + { + GNUNET_free (cgh); + return NULL; + } + cgh->contract_priv = *contract_priv; + + eh = TALER_EXCHANGE_curl_easy_get_ (cgh->url); + if (NULL == eh) + { + GNUNET_break (0); + GNUNET_free (cgh->url); + GNUNET_free (cgh); + return NULL; + } + cgh->job = GNUNET_CURL_job_add (ctx, + eh, + &handle_contract_get_finished, + cgh); + return cgh; +} + + +void +TALER_EXCHANGE_contract_get_cancel ( + struct TALER_EXCHANGE_ContractsGetHandle *cgh) +{ + if (NULL != cgh->job) + { + GNUNET_CURL_job_cancel (cgh->job); + cgh->job = NULL; + } + GNUNET_free (cgh->url); + GNUNET_free (cgh); +} + + +/* end of exchange_api_contracts_get.c */ |