/*
This file is part of TALER
Copyright (C) 2014-2017 Inria & GNUnet e.V.
TALER is free software; you can redistribute it and/or modify it under the
terms of the GNU Affero 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 Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License along with
TALER; see the file COPYING. If not, see
*/
/**
* @file taler-exchange-httpd_refresh_melt.c
* @brief Handle /refresh/melt requests
* @author Florian Dold
* @author Benedikt Mueller
* @author Christian Grothoff
*/
#include "platform.h"
#include
#include
#include
#include "taler-exchange-httpd_parsing.h"
#include "taler-exchange-httpd_mhd.h"
#include "taler-exchange-httpd_refresh_melt.h"
#include "taler-exchange-httpd_responses.h"
#include "taler-exchange-httpd_keystate.h"
/**
* @brief Details about a melt operation of an individual coin.
*/
struct TEH_DB_MeltDetails
{
/**
* Information about the coin being melted.
*/
struct TALER_CoinPublicInfo coin_info;
/**
* Signature allowing the melt (using
* a `struct TALER_EXCHANGEDB_RefreshMeltConfirmSignRequestBody`) to sign over.
*/
struct TALER_CoinSpendSignatureP melt_sig;
/**
* How much of the coin's value did the client allow to be melted?
* This amount includes the fees, so the final amount contributed
* to the melt is this value minus the fee for melting the coin.
*/
struct TALER_Amount melt_amount_with_fee;
/**
* What fee is earned by the exchange? Set delayed during
* #verify_coin_public_info().
*/
struct TALER_Amount melt_fee;
};
/**
* Send a response for a failed "/refresh/melt" request. The
* transaction history of the given coin demonstrates that the
* @a residual value of the coin is below the @a requested
* contribution of the coin for the melt. Thus, the exchange
* refuses the melt operation.
*
* @param connection the connection to send the response to
* @param coin_pub public key of the coin
* @param coin_value original value of the coin
* @param tl transaction history for the coin
* @param requested how much this coin was supposed to contribute, including fee
* @param residual remaining value of the coin (after subtracting @a tl)
* @return a MHD result code
*/
static int
reply_refresh_melt_insufficient_funds (struct MHD_Connection *connection,
const struct TALER_CoinSpendPublicKeyP *coin_pub,
struct TALER_Amount coin_value,
struct TALER_EXCHANGEDB_TransactionList *tl,
const struct TALER_Amount *requested,
const struct TALER_Amount *residual)
{
json_t *history;
history = TEH_RESPONSE_compile_transaction_history (tl);
if (NULL == history)
return TEH_RESPONSE_reply_internal_db_error (connection,
TALER_EC_REFRESH_MELT_HISTORY_DB_ERROR_INSUFFICIENT_FUNDS);
return TEH_RESPONSE_reply_json_pack (connection,
MHD_HTTP_FORBIDDEN,
"{s:s, s:I, s:o, s:o, s:o, s:o, s:o}",
"error",
"insufficient funds",
"code",
(json_int_t) TALER_EC_REFRESH_MELT_INSUFFICIENT_FUNDS,
"coin_pub",
GNUNET_JSON_from_data_auto (coin_pub),
"original_value",
TALER_JSON_from_amount (&coin_value),
"residual_value",
TALER_JSON_from_amount (residual),
"requested_value",
TALER_JSON_from_amount (requested),
"history",
history);
}
/**
* Send a response to a "/refresh/melt" request.
*
* @param connection the connection to send the response to
* @param session_hash hash of the refresh session
* @param noreveal_index which index will the client not have to reveal
* @return a MHD status code
*/
static int
reply_refresh_melt_success (struct MHD_Connection *connection,
const struct GNUNET_HashCode *session_hash,
uint16_t noreveal_index)
{
struct TALER_RefreshMeltConfirmationPS body;
struct TALER_ExchangePublicKeyP pub;
struct TALER_ExchangeSignatureP sig;
json_t *sig_json;
body.purpose.size = htonl (sizeof (struct TALER_RefreshMeltConfirmationPS));
body.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_MELT);
body.session_hash = *session_hash;
body.noreveal_index = htons (noreveal_index);
body.reserved = htons (0);
if (GNUNET_OK !=
TEH_KS_sign (&body.purpose,
&pub,
&sig))
{
return TEH_RESPONSE_reply_internal_error (connection,
TALER_EC_EXCHANGE_BAD_CONFIGURATION,
"no keys");
}
sig_json = GNUNET_JSON_from_data_auto (&sig);
GNUNET_assert (NULL != sig_json);
return TEH_RESPONSE_reply_json_pack (connection,
MHD_HTTP_OK,
"{s:i, s:o, s:o}",
"noreveal_index", (int) noreveal_index,
"exchange_sig", sig_json,
"exchange_pub", GNUNET_JSON_from_data_auto (&pub));
}
/**
* Context for the /refresh/melt operation.
*/
struct RefreshMeltContext
{
/**
* Key state that can be used to lookup keys.
*/
struct TEH_KS_StateHandle *key_state;
/**
* Information about the denomination key of the coin being
* melted.
*/
struct TALER_EXCHANGEDB_DenominationKeyIssueInformation *dki;
/**
* Array of denominations of the fresh coins.
*/
struct TALER_DenominationPublicKey *denom_pubs;
/**
* Number of new coins to be generated in the melt.
* Size of the @e denom_pubs array.
*/
unsigned int num_newcoins;
/**
* Details about the coin to be melted.
*/
struct TEH_DB_MeltDetails coin_melt_details;
/**
* Set to the session hash once the @e hash_context has finished.
*/
struct GNUNET_HashCode session_hash;
/**
* Hash operation used to calculate the session hash.
*/
struct GNUNET_HashContext *hash_context;
/**
* Committments to the blinded envelopes for the fresh coins.
*/
struct TALER_EXCHANGEDB_RefreshCommitCoin *commit_coin[TALER_CNC_KAPPA];
/**
* Commmittments to the transfer public keys.
*/
struct TALER_TransferPublicKeyP transfer_pub[TALER_CNC_KAPPA];
/**
* Initialized during #refresh_melt_transaction().
*/
struct TALER_EXCHANGEDB_RefreshSession refresh_session;
};
/**
* Parse coin melt requests from a JSON object and write them to
* the database.
*
* @param connection the connection to send errors to
* @param session the database connection
* @param[in,out] rmc melt context
* @param[out] mhd_ret status code to return to MHD on hard error
* @return transaction status code
*/
static enum GNUNET_DB_QueryStatus
refresh_check_melt (struct MHD_Connection *connection,
struct TALER_EXCHANGEDB_Session *session,
struct RefreshMeltContext *rmc,
int *mhd_ret)
{
struct TALER_EXCHANGEDB_TransactionList *tl;
struct TALER_EXCHANGEDB_RefreshMelt *meltp = &rmc->refresh_session.melt;
struct TALER_Amount coin_value;
struct TALER_Amount coin_residual;
struct TALER_Amount spent;
enum GNUNET_DB_QueryStatus qs;
TALER_amount_ntoh (&coin_value,
&rmc->dki->issue.properties.value);
/* fee for THIS transaction; the melt amount includes the fee! */
spent = rmc->coin_melt_details.melt_amount_with_fee;
/* add historic transaction costs of this coin */
qs = TEH_plugin->get_coin_transactions (TEH_plugin->cls,
session,
&rmc->coin_melt_details.coin_info.coin_pub,
&tl);
if (0 > qs)
{
if (GNUNET_DB_STATUS_HARD_ERROR == qs)
*mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection,
TALER_EC_REFRESH_MELT_DB_FETCH_ERROR);
return qs;
}
if (GNUNET_OK !=
TEH_DB_calculate_transaction_list_totals (tl,
&spent,
&spent))
{
GNUNET_break (0);
TEH_plugin->free_coin_transaction_list (TEH_plugin->cls,
tl);
*mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection,
TALER_EC_REFRESH_MELT_COIN_HISTORY_COMPUTATION_FAILED);
return GNUNET_DB_STATUS_HARD_ERROR;
}
/* Refuse to refresh when the coin's value is insufficient
for the cost of all transactions. */
if (TALER_amount_cmp (&coin_value,
&spent) < 0)
{
GNUNET_assert (GNUNET_SYSERR !=
TALER_amount_subtract (&coin_residual,
&spent,
&rmc->coin_melt_details.melt_amount_with_fee));
*mhd_ret = reply_refresh_melt_insufficient_funds (connection,
&rmc->coin_melt_details.coin_info.coin_pub,
coin_value,
tl,
&rmc->coin_melt_details.melt_amount_with_fee,
&coin_residual);
TEH_plugin->free_coin_transaction_list (TEH_plugin->cls,
tl);
return GNUNET_DB_STATUS_HARD_ERROR;
}
TEH_plugin->free_coin_transaction_list (TEH_plugin->cls,
tl);
meltp->coin = rmc->coin_melt_details.coin_info;
meltp->coin_sig = rmc->coin_melt_details.melt_sig;
meltp->session_hash = rmc->session_hash;
meltp->amount_with_fee = rmc->coin_melt_details.melt_amount_with_fee;
meltp->melt_fee = rmc->coin_melt_details.melt_fee;
return GNUNET_DB_STATUS_SUCCESS_ONE_RESULT;
}
/**
* Execute a "/refresh/melt". We have been given a list of valid
* coins and a request to melt them into the given @a
* refresh_session_pub. Check that the coins all have the required
* value left and if so, store that they have been melted and confirm
* the melting operation to the client.
*
* If it returns a non-error code, the transaction logic MUST NOT
* queue a MHD response. IF it returns an hard error, the transaction
* logic MUST queue a MHD response and set @a mhd_ret. If it returns
* the soft error code, the function MAY be called again to retry and
* MUST not queue a MHD response.
*
* @param cls our `struct RefreshMeltContext`
* @param connection MHD request which triggered the transaction
* @param session database session to use
* @param[out] mhd_ret set to MHD response status for @a connection,
* if transaction failed (!)
* @return transaction status
*/
static enum GNUNET_DB_QueryStatus
refresh_melt_transaction (void *cls,
struct MHD_Connection *connection,
struct TALER_EXCHANGEDB_Session *session,
int *mhd_ret)
{
struct RefreshMeltContext *rmc = cls;
enum GNUNET_DB_QueryStatus qs;
qs = TEH_plugin->get_refresh_session (TEH_plugin->cls,
session,
&rmc->session_hash,
&rmc->refresh_session);
if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT == qs)
{
*mhd_ret = reply_refresh_melt_success (connection,
&rmc->session_hash,
rmc->refresh_session.noreveal_index);
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (0 > qs)
{
if (GNUNET_DB_STATUS_HARD_ERROR == qs)
*mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection,
TALER_EC_REFRESH_MELT_DB_FETCH_ERROR);
return qs;
}
/* store 'global' session data */
rmc->refresh_session.num_newcoins = rmc->num_newcoins;
rmc->refresh_session.noreveal_index
= GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG,
TALER_CNC_KAPPA);
qs = refresh_check_melt (connection,
session,
rmc,
mhd_ret);
if (0 > qs)
return qs;
if ( (0 >=
(qs = TEH_plugin->create_refresh_session (TEH_plugin->cls,
session,
&rmc->session_hash,
&rmc->refresh_session))) ||
(0 >=
(qs = TEH_plugin->insert_refresh_order (TEH_plugin->cls,
session,
&rmc->session_hash,
rmc->num_newcoins,
rmc->denom_pubs))) ||
(0 >=
(qs = TEH_plugin->insert_refresh_commit_coins (TEH_plugin->cls,
session,
&rmc->session_hash,
rmc->num_newcoins,
rmc->commit_coin[rmc->refresh_session.noreveal_index]))) ||
(0 >=
(qs = TEH_plugin->insert_refresh_transfer_public_key (TEH_plugin->cls,
session,
&rmc->session_hash,
&rmc->transfer_pub[rmc->refresh_session.noreveal_index]))) )
{
if (GNUNET_DB_STATUS_SOFT_ERROR != qs)
{
*mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection,
TALER_EC_REFRESH_MELT_DB_STORE_SESSION_ERROR);
return GNUNET_DB_STATUS_HARD_ERROR;
}
return qs;
}
return GNUNET_DB_STATUS_SUCCESS_ONE_RESULT;
}
/**
* Handle a "/refresh/melt" request after the main JSON parsing has
* happened. We now need to validate the coins being melted and the
* session signature and then hand things of to execute the melt
* operation.
*
* @param connection the MHD connection to handle
* @param[out] mhd_ret set on failure to return value for MHD
* @param rmc information about the melt to process
* @return MHD result code
*/
static int
refresh_melt_prepare (struct MHD_Connection *connection,
int *mhd_ret,
struct RefreshMeltContext *rmc)
{
struct TALER_EXCHANGEDB_DenominationKeyIssueInformation *dk;
struct TALER_EXCHANGEDB_DenominationKeyInformationP *dki;
struct TALER_Amount cost;
struct TALER_Amount total_cost;
struct TALER_Amount value;
struct TALER_Amount fee_withdraw;
struct TALER_Amount fee_melt;
struct TALER_Amount total_melt;
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"/refresh/melt request for session %s\n",
GNUNET_h2s (&rmc->session_hash));
GNUNET_assert (GNUNET_OK ==
TALER_amount_get_zero (TEH_exchange_currency_string,
&total_cost));
for (unsigned int i=0;inum_newcoins;i++)
{
dk = TEH_KS_denomination_key_lookup (rmc->key_state,
&rmc->denom_pubs[i],
TEH_KS_DKU_WITHDRAW);
if (NULL == dk)
{
GNUNET_break_op (0);
*mhd_ret = TEH_RESPONSE_reply_arg_invalid (connection,
TALER_EC_REFRESH_MELT_FRESH_DENOMINATION_KEY_NOT_FOUND,
"new_denoms");
return GNUNET_SYSERR;
}
dki = &dk->issue;
TALER_amount_ntoh (&value,
&dki->properties.value);
TALER_amount_ntoh (&fee_withdraw,
&dki->properties.fee_withdraw);
if ( (GNUNET_OK !=
TALER_amount_add (&cost,
&value,
&fee_withdraw)) ||
(GNUNET_OK !=
TALER_amount_add (&total_cost,
&cost,
&total_cost)) )
{
GNUNET_break_op (0);
*mhd_ret = TEH_RESPONSE_reply_internal_error (connection,
TALER_EC_REFRESH_MELT_COST_CALCULATION_OVERFLOW,
"cost calculation failure");
return GNUNET_SYSERR;
}
}
dki = &rmc->dki->issue;
TALER_amount_ntoh (&fee_melt,
&dki->properties.fee_refresh);
if (GNUNET_OK !=
TALER_amount_subtract (&total_melt,
&rmc->coin_melt_details.melt_amount_with_fee,
&fee_melt))
{
GNUNET_break_op (0);
*mhd_ret = TEH_RESPONSE_reply_external_error (connection,
TALER_EC_REFRESH_MELT_FEES_EXCEED_CONTRIBUTION,
"Melt contribution below melting fee");
return GNUNET_SYSERR;
}
if (0 !=
TALER_amount_cmp (&total_cost,
&total_melt))
{
GNUNET_break_op (0);
/* We require total value of coins being melted and
total value of coins being generated to match! */
*mhd_ret = TEH_RESPONSE_reply_json_pack (connection,
MHD_HTTP_BAD_REQUEST,
"{s:s, s:I}",
"error", "value mismatch",
"code", (json_int_t) TALER_EC_REFRESH_MELT_FEES_MISSMATCH);
return GNUNET_SYSERR;
}
return TEH_DB_run_transaction (connection,
mhd_ret,
&refresh_melt_transaction,
rmc);
}
/**
* Extract public coin information from a JSON object.
*
* @param connection the connection to send error responses to
* @param coin_info the JSON object to extract the coin info from
* @param[out] r_melt_detail set to details about the coin's melting permission (if valid)
* @return #GNUNET_YES if coin public info in JSON was valid
* #GNUNET_NO JSON was invalid, response was generated
* #GNUNET_SYSERR on internal error
*/
static int
get_coin_public_info (struct MHD_Connection *connection,
const json_t *coin_info,
struct TEH_DB_MeltDetails *r_melt_detail)
{
int ret;
struct TALER_CoinSpendSignatureP melt_sig;
struct TALER_DenominationSignature sig;
struct TALER_DenominationPublicKey pk;
struct TALER_Amount amount;
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_fixed_auto ("coin_pub", &r_melt_detail->coin_info.coin_pub),
TALER_JSON_spec_denomination_signature ("denom_sig", &sig),
TALER_JSON_spec_denomination_public_key ("denom_pub", &pk),
GNUNET_JSON_spec_fixed_auto ("confirm_sig", &melt_sig),
TALER_JSON_spec_amount ("value_with_fee", &amount),
GNUNET_JSON_spec_end ()
};
ret = TEH_PARSE_json_data (connection,
coin_info,
spec);
if (GNUNET_OK != ret)
{
GNUNET_break_op (0);
return ret;
}
/* check exchange signature on the coin */
r_melt_detail->coin_info.denom_sig = sig;
r_melt_detail->coin_info.denom_pub = pk;
if (GNUNET_OK !=
TALER_test_coin_valid (&r_melt_detail->coin_info))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
r_melt_detail->coin_info.denom_sig.rsa_signature = NULL;
r_melt_detail->coin_info.denom_pub.rsa_public_key = NULL;
return (MHD_YES ==
TEH_RESPONSE_reply_signature_invalid (connection,
TALER_EC_REFRESH_MELT_DENOMINATION_SIGNATURE_INVALID,
"denom_sig"))
? GNUNET_NO : GNUNET_SYSERR;
}
r_melt_detail->melt_sig = melt_sig;
r_melt_detail->melt_amount_with_fee = amount;
return GNUNET_OK;
}
/**
* Release memory from the @a commit_coin array.
*
* @param commit_coin array to release
* @param kappa size of 1st dimension
* @param num_new_coins size of 2nd dimension
*/
static void
free_commit_coins (struct TALER_EXCHANGEDB_RefreshCommitCoin **commit_coin,
unsigned int kappa,
unsigned int num_new_coins)
{
for (unsigned int i=0;icommit_coin,
TALER_CNC_KAPPA,
rmc->num_newcoins);
if (NULL != rmc->coin_melt_details.coin_info.denom_pub.rsa_public_key)
{
GNUNET_CRYPTO_rsa_public_key_free (rmc->coin_melt_details.coin_info.denom_pub.rsa_public_key);
rmc->coin_melt_details.coin_info.denom_pub.rsa_public_key = NULL;
}
if (NULL != rmc->coin_melt_details.coin_info.denom_sig.rsa_signature)
{
GNUNET_CRYPTO_rsa_signature_free (rmc->coin_melt_details.coin_info.denom_sig.rsa_signature);
rmc->coin_melt_details.coin_info.denom_sig.rsa_signature = NULL;
}
if (NULL != rmc->denom_pubs)
{
for (unsigned int j=0;jnum_newcoins;j++)
if (NULL != rmc->denom_pubs[j].rsa_public_key)
GNUNET_CRYPTO_rsa_public_key_free (rmc->denom_pubs[j].rsa_public_key);
GNUNET_free (rmc->denom_pubs);
rmc->denom_pubs = NULL;
}
if (NULL != rmc->hash_context)
{
GNUNET_CRYPTO_hash_context_abort (rmc->hash_context);
rmc->hash_context = NULL;
}
if (NULL != rmc->key_state)
{
TEH_KS_release (rmc->key_state);
rmc->key_state = NULL;
}
}
/**
* Handle a "/refresh/melt" request after the first parsing has
* happened. We now need to validate the coins being melted and the
* session signature and then hand things of to execute the melt
* operation. This function parses the JSON arrays and then passes
* processing on to #handle_refresh_melt_binary().
*
* @param connection the MHD connection to handle
* @param new_denoms array of denomination keys
* @param melt_coin coin to melt
* @param transfer_pubs #TALER_CNC_KAPPA-dimensional array of transfer keys
* @param coin_evs #TALER_CNC_KAPPA-dimensional array of envelopes to sign
* @return MHD result code
*/
static int
handle_refresh_melt_json (struct MHD_Connection *connection,
const json_t *new_denoms,
const json_t *melt_coin,
const json_t *transfer_pubs,
const json_t *coin_evs)
{
int res;
int mhd_ret;
struct RefreshMeltContext rmc;
memset (&rmc,
0,
sizeof (rmc));
/* For the signature check, we hash most of the inputs together
(except for the signatures on the coins). */
rmc.hash_context = GNUNET_CRYPTO_hash_context_start ();
for (unsigned int i = 0; i < TALER_CNC_KAPPA; i++)
{
struct GNUNET_JSON_Specification trans_spec[] = {
GNUNET_JSON_spec_fixed_auto (NULL, &rmc.transfer_pub[i]),
GNUNET_JSON_spec_end ()
};
res = TEH_PARSE_json_array (connection,
transfer_pubs,
trans_spec,
i, -1);
if (GNUNET_OK != res)
{
GNUNET_break_op (0);
mhd_ret = (GNUNET_SYSERR == res) ? MHD_NO : MHD_YES;
cleanup_rmc (&rmc);
return mhd_ret;
}
GNUNET_CRYPTO_hash_context_read (rmc.hash_context,
&rmc.transfer_pub[i],
sizeof (struct TALER_TransferPublicKeyP));
}
rmc.num_newcoins = json_array_size (new_denoms);
rmc.denom_pubs = GNUNET_new_array (rmc.num_newcoins,
struct TALER_DenominationPublicKey);
for (unsigned int i=0;icoin_ev,
&rcc->coin_ev_size),
GNUNET_JSON_spec_end ()
};
res = TEH_PARSE_json_array (connection,
coin_evs,
coin_spec,
i,
j,
-1);
if (GNUNET_OK != res)
{
GNUNET_break_op (0);
mhd_ret = (GNUNET_SYSERR == res) ? MHD_NO : MHD_YES;
cleanup_rmc (&rmc);
return mhd_ret;
}
GNUNET_CRYPTO_hash_context_read (rmc.hash_context,
rcc->coin_ev,
rcc->coin_ev_size);
}
}
GNUNET_CRYPTO_hash_context_finish (rmc.hash_context,
&rmc.session_hash);
rmc.hash_context = NULL;
rmc.key_state = TEH_KS_acquire ();
if (NULL == rmc.key_state)
{
TALER_LOG_ERROR ("Lacking keys to operate\n");
return TEH_RESPONSE_reply_internal_error (connection,
TALER_EC_EXCHANGE_BAD_CONFIGURATION,
"no keys");
}
rmc.dki = TEH_KS_denomination_key_lookup (rmc.key_state,
&rmc.coin_melt_details.coin_info.denom_pub,
TEH_KS_DKU_DEPOSIT);
if (NULL == rmc.dki)
{
TEH_KS_release (rmc.key_state);
TALER_LOG_WARNING ("Unknown denomination key in /refresh/melt request\n");
return TEH_RESPONSE_reply_arg_unknown (connection,
TALER_EC_REFRESH_MELT_DENOMINATION_KEY_NOT_FOUND,
"denom_pub");
}
/* verify signature of coin for melt operation */
{
struct TALER_RefreshMeltCoinAffirmationPS body;
struct TALER_Amount fee_refresh;
TALER_amount_ntoh (&fee_refresh,
&rmc.dki->issue.properties.fee_refresh);
rmc.coin_melt_details.melt_fee = fee_refresh;
body.purpose.size = htonl (sizeof (struct TALER_RefreshMeltCoinAffirmationPS));
body.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_MELT);
body.session_hash = rmc.session_hash;
TALER_amount_hton (&body.amount_with_fee,
&rmc.coin_melt_details.melt_amount_with_fee);
TALER_amount_hton (&body.melt_fee,
&fee_refresh);
body.coin_pub = rmc.coin_melt_details.coin_info.coin_pub;
if (TALER_amount_cmp (&fee_refresh,
&rmc.coin_melt_details.melt_amount_with_fee) > 0)
{
GNUNET_break_op (0);
cleanup_rmc (&rmc);
return TEH_RESPONSE_reply_external_error (connection,
TALER_EC_REFRESH_MELT_AMOUNT_INSUFFICIENT,
"melt amount smaller than melting fee");
}
if (GNUNET_OK !=
GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_WALLET_COIN_MELT,
&body.purpose,
&rmc.coin_melt_details.melt_sig.eddsa_signature,
&rmc.coin_melt_details.coin_info.coin_pub.eddsa_pub))
{
GNUNET_break_op (0);
cleanup_rmc (&rmc);
return TEH_RESPONSE_reply_signature_invalid (connection,
TALER_EC_REFRESH_MELT_COIN_SIGNATURE_INVALID,
"confirm_sig");
}
}
/* prepare commit */
if (GNUNET_OK !=
refresh_melt_prepare (connection,
&mhd_ret,
&rmc))
{
cleanup_rmc (&rmc);
return mhd_ret;
}
mhd_ret = reply_refresh_melt_success (connection,
&rmc.session_hash,
rmc.refresh_session.noreveal_index);
cleanup_rmc (&rmc);
return mhd_ret;
}
/**
* Handle a "/refresh/melt" request. Parses the request into the JSON
* components and then hands things of to #handle_refresh_melt_json()
* to validate the melted coins, the signature and execute the melt
* using TEH_DB_execute_refresh_melt().
*
* @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
* @return MHD result code
*/
int
TEH_REFRESH_handler_refresh_melt (struct TEH_RequestHandler *rh,
struct MHD_Connection *connection,
void **connection_cls,
const char *upload_data,
size_t *upload_data_size)
{
json_t *root;
json_t *new_denoms;
json_t *melt_coin;
json_t *coin_evs;
json_t *transfer_pubs;
int res;
struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_json ("new_denoms", &new_denoms),
GNUNET_JSON_spec_json ("melt_coin", &melt_coin),
GNUNET_JSON_spec_json ("coin_evs", &coin_evs),
GNUNET_JSON_spec_json ("transfer_pubs", &transfer_pubs),
GNUNET_JSON_spec_end ()
};
res = TEH_PARSE_post_json (connection,
connection_cls,
upload_data,
upload_data_size,
&root);
if (GNUNET_SYSERR == res)
return MHD_NO;
if ( (GNUNET_NO == res) ||
(NULL == root) )
return MHD_YES;
res = TEH_PARSE_json_data (connection,
root,
spec);
json_decref (root);
if (GNUNET_OK != res)
return (GNUNET_SYSERR == res) ? MHD_NO : MHD_YES;
/* Determine dimensionality of the request (kappa, #old and #new coins) */
if (TALER_CNC_KAPPA != json_array_size (coin_evs))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TEH_RESPONSE_reply_arg_invalid (connection,
TALER_EC_REFRESH_MELT_CNC_COIN_ARRAY_SIZE_INVALID,
"coin_evs");
}
if (TALER_CNC_KAPPA != json_array_size (transfer_pubs))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TEH_RESPONSE_reply_arg_invalid (connection,
TALER_EC_REFRESH_MELT_CNC_TRANSFER_ARRAY_SIZE_INVALID,
"transfer_pubs");
}
res = handle_refresh_melt_json (connection,
new_denoms,
melt_coin,
transfer_pubs,
coin_evs);
GNUNET_JSON_parse_free (spec);
return res;
}
/* end of taler-exchange-httpd_refresh_melt.c */