diff options
Diffstat (limited to 'src/lib/exchange_api_refresh_link.c')
| -rw-r--r-- | src/lib/exchange_api_refresh_link.c | 490 |
1 files changed, 0 insertions, 490 deletions
diff --git a/src/lib/exchange_api_refresh_link.c b/src/lib/exchange_api_refresh_link.c deleted file mode 100644 index 4b4b38ba..00000000 --- a/src/lib/exchange_api_refresh_link.c +++ /dev/null @@ -1,490 +0,0 @@ -/* - This file is part of TALER - Copyright (C) 2015-2020 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 lib/exchange_api_refresh_link.c - * @brief Implementation of the /refresh/link request of the exchange's HTTP API - * @author Christian Grothoff - */ -#include "platform.h" -#include <microhttpd.h> /* just for HTTP status codes */ -#include <gnunet/gnunet_util_lib.h> -#include <gnunet/gnunet_curl_lib.h> -#include "taler_exchange_service.h" -#include "taler_json_lib.h" -#include "exchange_api_handle.h" -#include "taler_signatures.h" -#include "exchange_api_curl_defaults.h" - - -/** - * @brief A /refresh/link Handle - */ -struct TALER_EXCHANGE_RefreshLinkHandle -{ - - /** - * The connection to exchange this request handle will use - */ - struct TALER_EXCHANGE_Handle *exchange; - - /** - * The url for this request. - */ - char *url; - - /** - * Handle for the request. - */ - struct GNUNET_CURL_Job *job; - - /** - * Function to call with the result. - */ - TALER_EXCHANGE_RefreshLinkCallback link_cb; - - /** - * Closure for @e cb. - */ - void *link_cb_cls; - - /** - * Private key of the coin, required to decode link information. - */ - struct TALER_CoinSpendPrivateKeyP coin_priv; - -}; - - -/** - * Parse the provided linkage data from the "200 OK" response - * for one of the coins. - * - * @param rlh refresh link handle - * @param json json reply with the data for one coin - * @param coin_num number of the coin to decode - * @param trans_pub our transfer public key - * @param[out] coin_priv where to return private coin key - * @param[out] sig where to return private coin signature - * @param[out] pub where to return the public key for the coin - * @return #GNUNET_OK on success, #GNUNET_SYSERR on error - */ -static int -parse_refresh_link_coin (const struct TALER_EXCHANGE_RefreshLinkHandle *rlh, - const json_t *json, - unsigned int coin_num, - const struct TALER_TransferPublicKeyP *trans_pub, - struct TALER_CoinSpendPrivateKeyP *coin_priv, - struct TALER_DenominationSignature *sig, - struct TALER_DenominationPublicKey *pub) -{ - struct GNUNET_CRYPTO_RsaSignature *bsig; - struct GNUNET_CRYPTO_RsaPublicKey *rpub; - struct TALER_CoinSpendSignatureP link_sig; - struct GNUNET_JSON_Specification spec[] = { - GNUNET_JSON_spec_rsa_public_key ("denom_pub", &rpub), - GNUNET_JSON_spec_rsa_signature ("ev_sig", &bsig), - GNUNET_JSON_spec_fixed_auto ("link_sig", &link_sig), - GNUNET_JSON_spec_end () - }; - struct TALER_TransferSecretP secret; - struct TALER_PlanchetSecretsP fc; - - /* parse reply */ - if (GNUNET_OK != - GNUNET_JSON_parse (json, - spec, - NULL, NULL)) - { - GNUNET_break_op (0); - return GNUNET_SYSERR; - } - - TALER_link_recover_transfer_secret (trans_pub, - &rlh->coin_priv, - &secret); - TALER_planchet_setup_refresh (&secret, - coin_num, - &fc); - - /* extract coin and signature */ - *coin_priv = fc.coin_priv; - sig->rsa_signature - = GNUNET_CRYPTO_rsa_unblind (bsig, - &fc.blinding_key.bks, - rpub); - /* verify link_sig */ - { - struct TALER_LinkDataPS ldp; - struct TALER_PlanchetDetail pd; - - ldp.purpose.size = htonl (sizeof (ldp)); - ldp.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_LINK); - GNUNET_CRYPTO_eddsa_key_get_public (&rlh->coin_priv.eddsa_priv, - &ldp.old_coin_pub.eddsa_pub); - ldp.transfer_pub = *trans_pub; - pub->rsa_public_key = rpub; - if (GNUNET_OK != - TALER_planchet_prepare (pub, - &fc, - &pd)) - { - GNUNET_break (0); - GNUNET_JSON_parse_free (spec); - return GNUNET_SYSERR; - } - ldp.h_denom_pub = pd.denom_pub_hash; - GNUNET_CRYPTO_hash (pd.coin_ev, - pd.coin_ev_size, - &ldp.coin_envelope_hash); - GNUNET_free (pd.coin_ev); - - if (GNUNET_OK != - GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_WALLET_COIN_LINK, - &ldp.purpose, - &link_sig.eddsa_signature, - &ldp.old_coin_pub.eddsa_pub)) - { - GNUNET_break_op (0); - GNUNET_JSON_parse_free (spec); - return GNUNET_SYSERR; - } - } - - /* clean up */ - pub->rsa_public_key = GNUNET_CRYPTO_rsa_public_key_dup (rpub); - GNUNET_JSON_parse_free (spec); - return GNUNET_OK; -} - - -/** - * Parse the provided linkage data from the "200 OK" response - * for one of the coins. - * - * @param[in,out] rlh refresh link handle (callback may be zero'ed out) - * @param json json reply with the data for one coin - * @return #GNUNET_OK on success, #GNUNET_SYSERR on error - */ -static int -parse_refresh_link_ok (struct TALER_EXCHANGE_RefreshLinkHandle *rlh, - const json_t *json) -{ - unsigned int session; - unsigned int num_coins; - int ret; - - if (! json_is_array (json)) - { - GNUNET_break_op (0); - return GNUNET_SYSERR; - } - num_coins = 0; - /* Theoretically, a coin may have been melted repeatedly - into different sessions; so the response is an array - which contains information by melting session. That - array contains another array. However, our API returns - a single 1d array, so we flatten the 2d array that is - returned into a single array. Note that usually a coin - is melted at most once, and so we'll only run this - loop once for 'session=0' in most cases. - - num_coins tracks the size of the 1d array we return, - whilst 'i' and 'session' track the 2d array. */// - for (session = 0; session<json_array_size (json); session++) - { - json_t *jsona; - struct GNUNET_JSON_Specification spec[] = { - GNUNET_JSON_spec_json ("new_coins", &jsona), - GNUNET_JSON_spec_end () - }; - - if (GNUNET_OK != - GNUNET_JSON_parse (json_array_get (json, - session), - spec, - NULL, NULL)) - { - GNUNET_break_op (0); - return GNUNET_SYSERR; - } - if (! json_is_array (jsona)) - { - GNUNET_break_op (0); - GNUNET_JSON_parse_free (spec); - return GNUNET_SYSERR; - } - - /* count all coins over all sessions */ - num_coins += json_array_size (jsona); - GNUNET_JSON_parse_free (spec); - } - /* Now that we know how big the 1d array is, allocate - and fill it. */ - { - unsigned int off_coin; /* index into 1d array */ - unsigned int i; - struct TALER_CoinSpendPrivateKeyP coin_privs[GNUNET_NZL (num_coins)]; - struct TALER_DenominationSignature sigs[GNUNET_NZL (num_coins)]; - struct TALER_DenominationPublicKey pubs[GNUNET_NZL (num_coins)]; - - memset (sigs, 0, sizeof (sigs)); - memset (pubs, 0, sizeof (pubs)); - off_coin = 0; - for (session = 0; session<json_array_size (json); session++) - { - json_t *jsona; - struct TALER_TransferPublicKeyP trans_pub; - struct GNUNET_JSON_Specification spec[] = { - GNUNET_JSON_spec_json ("new_coins", - &jsona), - GNUNET_JSON_spec_fixed_auto ("transfer_pub", - &trans_pub), - GNUNET_JSON_spec_end () - }; - - if (GNUNET_OK != - GNUNET_JSON_parse (json_array_get (json, - session), - spec, - NULL, NULL)) - { - GNUNET_break_op (0); - return GNUNET_SYSERR; - } - if (! json_is_array (jsona)) - { - GNUNET_break_op (0); - GNUNET_JSON_parse_free (spec); - return GNUNET_SYSERR; - } - - /* decode all coins */ - for (i = 0; i<json_array_size (jsona); i++) - { - GNUNET_assert (i + off_coin < num_coins); - if (GNUNET_OK != - parse_refresh_link_coin (rlh, - json_array_get (jsona, - i), - i, - &trans_pub, - &coin_privs[i + off_coin], - &sigs[i + off_coin], - &pubs[i + off_coin])) - { - GNUNET_break_op (0); - break; - } - } - /* check if we really got all, then invoke callback */ - off_coin += i; - if (i != json_array_size (jsona)) - { - GNUNET_break_op (0); - ret = GNUNET_SYSERR; - GNUNET_JSON_parse_free (spec); - break; - } - GNUNET_JSON_parse_free (spec); - } /* end of for (session) */ - - if (off_coin == num_coins) - { - rlh->link_cb (rlh->link_cb_cls, - MHD_HTTP_OK, - TALER_EC_NONE, - num_coins, - coin_privs, - sigs, - pubs, - json); - rlh->link_cb = NULL; - ret = GNUNET_OK; - } - else - { - GNUNET_break_op (0); - ret = GNUNET_SYSERR; - } - - /* clean up */ - GNUNET_assert (off_coin <= num_coins); - for (i = 0; i<off_coin; i++) - { - if (NULL != sigs[i].rsa_signature) - GNUNET_CRYPTO_rsa_signature_free (sigs[i].rsa_signature); - if (NULL != pubs[i].rsa_public_key) - GNUNET_CRYPTO_rsa_public_key_free (pubs[i].rsa_public_key); - } - } - return ret; -} - - -/** - * Function called when we're done processing the - * HTTP /refresh/link request. - * - * @param cls the `struct TALER_EXCHANGE_RefreshLinkHandle` - * @param response_code HTTP response code, 0 on error - * @param response parsed JSON result, NULL on error - */ -static void -handle_refresh_link_finished (void *cls, - long response_code, - const void *response) -{ - struct TALER_EXCHANGE_RefreshLinkHandle *rlh = cls; - const json_t *j = response; - - rlh->job = NULL; - switch (response_code) - { - case 0: - break; - case MHD_HTTP_OK: - if (GNUNET_OK != - parse_refresh_link_ok (rlh, - j)) - { - GNUNET_break_op (0); - response_code = 0; - } - 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_NOT_FOUND: - /* Nothing really to verify, exchange says this coin was not melted; we - should pass the JSON 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; - } - if (NULL != rlh->link_cb) - rlh->link_cb (rlh->link_cb_cls, - response_code, - TALER_JSON_get_error_code (j), - 0, - NULL, - NULL, - NULL, - j); - TALER_EXCHANGE_refresh_link_cancel (rlh); -} - - -/** - * Submit a link request to the exchange and get the exchange's response. - * - * This API is typically not used by anyone, it is more a threat - * against those trying to receive a funds transfer by abusing the - * /refresh protocol. - * - * @param exchange the exchange handle; the exchange must be ready to operate - * @param coin_priv private key to request link data for - * @param link_cb the callback to call with the useful result of the - * refresh operation the @a coin_priv was involved in (if any) - * @param link_cb_cls closure for @a link_cb - * @return a handle for this request - */ -struct TALER_EXCHANGE_RefreshLinkHandle * -TALER_EXCHANGE_refresh_link (struct TALER_EXCHANGE_Handle *exchange, - const struct TALER_CoinSpendPrivateKeyP *coin_priv, - TALER_EXCHANGE_RefreshLinkCallback link_cb, - void *link_cb_cls) -{ - struct TALER_EXCHANGE_RefreshLinkHandle *rlh; - CURL *eh; - struct GNUNET_CURL_Context *ctx; - struct TALER_CoinSpendPublicKeyP coin_pub; - char arg_str[sizeof (struct TALER_CoinSpendPublicKeyP) * 2 + 32]; - - if (GNUNET_YES != - TEAH_handle_is_ready (exchange)) - { - GNUNET_break (0); - return NULL; - } - - GNUNET_CRYPTO_eddsa_key_get_public (&coin_priv->eddsa_priv, - &coin_pub.eddsa_pub); - { - char pub_str[sizeof (struct TALER_CoinSpendPublicKeyP) * 2]; - char *end; - - end = GNUNET_STRINGS_data_to_string (&coin_pub, - sizeof (struct - TALER_CoinSpendPublicKeyP), - pub_str, - sizeof (pub_str)); - *end = '\0'; - GNUNET_snprintf (arg_str, - sizeof (arg_str), - "/coins/%s/link", - pub_str); - } - rlh = GNUNET_new (struct TALER_EXCHANGE_RefreshLinkHandle); - rlh->exchange = exchange; - rlh->link_cb = link_cb; - rlh->link_cb_cls = link_cb_cls; - rlh->coin_priv = *coin_priv; - rlh->url = TEAH_path_to_url (exchange, - arg_str); - eh = TEL_curl_easy_get (rlh->url); - ctx = TEAH_handle_to_context (exchange); - rlh->job = GNUNET_CURL_job_add (ctx, - eh, - GNUNET_YES, - &handle_refresh_link_finished, - rlh); - return rlh; -} - - -/** - * Cancel a refresh link request. This function cannot be used - * on a request handle if the callback was already invoked. - * - * @param rlh the refresh link handle - */ -void -TALER_EXCHANGE_refresh_link_cancel (struct - TALER_EXCHANGE_RefreshLinkHandle *rlh) -{ - if (NULL != rlh->job) - { - GNUNET_CURL_job_cancel (rlh->job); - rlh->job = NULL; - } - GNUNET_free (rlh->url); - GNUNET_free (rlh); -} - - -/* end of exchange_api_refresh_link.c */ |