taler/exchange
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

starting work on purse-create endpoint

Browse Source
This commit is contained in:
Christian Grothoff 2022-03-28 17:50:23 +02:00
parent a227ee6d1b
commit b25c9398b7
No known key found for this signature in database
GPG Key ID: 939E6BE1E29FC3CC
4 changed files with 637 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

609
src/exchange/taler-exchange-httpd_purses_create.c Normal file
View File

@ -0,0 +1,609 @@
/*
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 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 <http://www.gnu.org/licenses/>
*/
/**
* @file taler-exchange-httpd_purses_create.c
* @brief Handle /purses/$PID/create requests; parses the POST and JSON and
* verifies the coin signature before handing things off
* to the database.
* @author Christian Grothoff
*/
#include "platform.h"
#include <gnunet/gnunet_util_lib.h>
#include <gnunet/gnunet_json_lib.h>
#include <jansson.h>
#include <microhttpd.h>
#include <pthread.h>
#include "taler_json_lib.h"
#include "taler_mhd_lib.h"
#include "taler-exchange-httpd_purses_create.h"
#include "taler-exchange-httpd_responses.h"
#include "taler_exchangedb_lib.h"
#include "taler-exchange-httpd_keys.h"
/**
* Information about an individual coin being deposited.
*/
struct Coin
{
/**
* Public information about the coin.
*/
struct TALER_CoinPublicInfo cpi;
/**
* Signature affirming spending the coin.
*/
struct TALER_CoinSpendSignatureP coin_sig;
/**
* Amount to be put into the purse from this coin.
*/
struct TALER_Amount amount;
/**
* Deposit fee applicable for this coin.
*/
struct TALER_Amount deposit_fee;
};
/**
* Closure for #create_transaction.
*/
struct PurseCreateContext
{
/**
* Public key of the purse we are creating.
*/
const struct TALER_PurseContractPublicKeyP *purse_pub;
/**
* Total amount to be put into the purse.
*/
struct TALER_Amount amount;
/**
* Total actually deposited by all the coins.
*/
struct TALER_Amount deposit_total;
/**
* When should the purse expire.
*/
struct GNUNET_TIME_Timestamp purse_expiration;
/**
* Our current time.
*/
struct GNUNET_TIME_Timestamp exchange_timestamp;
/**
* Merge key for the purse.
*/
struct TALER_PurseMergePublicKeyP merge_pub;
/**
* Contract decryption key for the purse.
*/
struct TALER_ContractDiffiePublicP contract_pub;
/**
* Signature of the client affiming this request.
*/
struct TALER_PurseContractSignatureP purse_sig;
/**
* Hash of the contract terms of the purse.
*/
struct TALER_PrivateContractHashP h_contract_terms;
/**
* Array of coins being deposited.
*/
struct Coin *coins;
/**
* Encrypted contract, can be NULL.
*/
void *econtract;
/**
* Number of bytes in @e econtract.
*/
size_t econtract_size;
/**
* Length of the @e coins array.
*/
unsigned int num_coins;
};
/**
* Send confirmation of purse creation success to client.
*
* @param connection connection to the client
* @param pcc details about the request that succeeded
* @return MHD result code
*/
static MHD_RESULT
reply_create_success (struct MHD_Connection *connection,
const struct PurseCreateContext *pcc)
{
struct TALER_ExchangePublicKeyP pub;
struct TALER_ExchangeSignatureP sig;
// FIXME: define what exactly we sign over!
struct TALER_DepositConfirmationPS dc = {
.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_PURSE_CREATION),
.purpose.size = htonl (sizeof (dc)),
.h_contract_terms = pcc->h_contract_terms,
.purse_pub = *pcc->purse_pub
};
enum TALER_ErrorCode ec;
TALER_amount_hton (&dc.amount_without_fee,
&pcc->amount);
if (TALER_EC_NONE !=
(ec = TEH_keys_exchange_sign (&dc,
&pub,
&sig)))
{
return TALER_MHD_reply_with_ec (connection,
ec,
NULL);
}
return TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_OK,
// GNUNET_JSON_pack_timestamp ("exchange_timestamp",
// pcc->exchange_timestamp),
GNUNET_JSON_pack_data_auto ("exchange_sig",
&sig),
GNUNET_JSON_pack_data_auto ("exchange_pub",
&pub));
}
/**
* Execute database transaction for /purses/$PID/create. Runs the transaction
* logic; 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 a `struct PurseCreateContext`
* @param connection MHD request context
* @param[out] mhd_ret set to MHD status on error
* @return transaction status
*/
static enum GNUNET_DB_QueryStatus
create_transaction (void *cls,
struct MHD_Connection *connection,
MHD_RESULT *mhd_ret)
{
struct PurseCreateContext *pcc = cls;
enum GNUNET_DB_QueryStatus qs;
bool balance_ok;
bool in_conflict;
// 1) create purse
// 2) deposit all coins
// 3) if present, persist contract
// Also: nicely report errors...
qs = TEH_plugin->XXX (TEH_plugin->cls, ...);
if (qs < 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
TALER_LOG_WARNING ("Failed to store purse information in database\n");
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_STORE_FAILED,
"purse create");
return qs;
}
if (in_conflict)
{
TEH_plugin->rollback (TEH_plugin->cls);
*mhd_ret
= TEH_RESPONSE_reply_coin_insufficient_funds (
connection,
TALER_EC_EXCHANGE_PURSE_CREATE_CONFLICTING_CONTRACT,
&coin->pci.coin_pub);
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (! balance_ok)
{
TEH_plugin->rollback (TEH_plugin->cls);
*mhd_ret
= TEH_RESPONSE_reply_coin_insufficient_funds (
connection,
TALER_EC_EXCHANGE_GENERIC_INSUFFICIENT_FUNDS,
&coin->pci.coin_pub);
return GNUNET_DB_STATUS_HARD_ERROR;
}
return qs;
}
/**
* Parse a coin and check signature of the coin and the denomination
* signature over the coin.
*
* @param[in,out] our HTTP connection
* @param[in,out] request context
* @param[out] coin coin to initialize
* @param jcoin coin to parse
* @return #GNUNET_OK on success, #GNUNET_NO if an error was returned,
* #GNUNET_SYSERR on failure and no error could be returned
*/
static enum GNUNET_GenericReturnValue
parse_coin (struct MHD_Connection *connection,
struct PurseCreateContext *pcc,
struct Coin *coin,
const json_t *jcoin)
{
struct GNUNET_JSON_Specification spec[] = {
TALER_JSON_spec_amount ("amount",
TEH_currency,
&coin->amount),
GNUNET_JSON_spec_fixed_auto ("denom_pub_hash",
&coin->cpi.denom_pub_hash),
TALER_JSON_spec_denom_sig ("ub_sig",
&coin->cpi.denom_sig),
GNUNET_JSON_spec_mark_optional (
GNUNET_JSON_spec_fixed_auto ("h_age_commitment",
&coin->cpi.h_age_commitment)),
&coin->cpi.no_age_commitment),
GNUNET_JSON_spec_fixed_auto ("coin_sig",
&coin->coin_sig),
GNUNET_JSON_spec_fixed_auto ("coin_pub",
&coin->cpi.coin_pub),
GNUNET_JSON_spec_end ()
};
{
enum GNUNET_GenericReturnValue res;
res = TALER_MHD_parse_json_data (connection,
jcoin,
spec);
if (GNUNET_OK != res)
return res;
}
if (GNUNET_OK !=
TALER_wallet_purse_deposit_verify ("http://FIXME-URL",
&pcc->purse_pub,
&pcc->amount,
&coin->coin_pub,
&coin->csig))
{
TALER_LOG_WARNING ("Invalid signature on /purses/$PID/create request\n");
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_UNAUTHORIZED,
TALER_EC_EXCHANGE_PURSE_CREATE_COIN_SIGNATURE_INVALID,
NULL))
? GNUNET_NO : GNUNET_SYSERR;
}
/* check denomination exists and is valid */
{
struct TEH_DenominationKey *dk;
MHD_RESULT mret;
dk = TEH_keys_denomination_by_hash (&coin->denom_pub_hash,
connection,
&mret);
if (NULL == dk)
{
GNUNET_JSON_parse_free (spec);
return (MHD_YES == mret) ? GNUNET_NO : GNUNET_SYSERR:
}
if (GNUNET_TIME_absolute_is_past (dk->meta.expire_deposit.abs_time))
{
/* This denomination is past the expiration time for deposits */
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TEH_RESPONSE_reply_expired_denom_pub_hash (
connection,
&coin->denom_pub_hash,
TALER_EC_EXCHANGE_GENERIC_DENOMINATION_EXPIRED,
"PURSE CREATE"))
? GNUNET_NO : GNUNET_SYSERR:
}
if (GNUNET_TIME_absolute_is_future (dk->meta.start.abs_time))
{
/* This denomination is not yet valid */
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TEH_RESPONSE_reply_expired_denom_pub_hash (
connection,
&coin->denom_pub_hash,
TALER_EC_EXCHANGE_GENERIC_DENOMINATION_VALIDITY_IN_FUTURE,
"PURSE CREATE"))
? GNUNET_NO : GNUNET_SYSERR;
}
if (dk->recoup_possible)
{
/* This denomination has been revoked */
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TEH_RESPONSE_reply_expired_denom_pub_hash (
connection,
&deposit.coin.denom_pub_hash,
TALER_EC_EXCHANGE_GENERIC_DENOMINATION_REVOKED,
"PURSE CREATE"))
? GNUNET_NO : GNUNET_SYSERR;
}
if (dk->denom_pub.cipher != deposit.coin.denom_sig.cipher)
{
/* denomination cipher and denomination signature cipher not the same */
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_GENERIC_CIPHER_MISMATCH,
NULL))
? GNUNET_NO : GNUNET_SYSERR;
}
coin->deposit_fee = dk->meta.fees.deposit;
/* check coin signature */
switch (dk->denom_pub.cipher)
{
case TALER_DENOMINATION_RSA:
TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_RSA]++;
break;
case TALER_DENOMINATION_CS:
TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_CS]++;
break;
default:
break;
}
if (GNUNET_YES !=
TALER_test_coin_valid (&deposit.coin,
&dk->denom_pub))
{
TALER_LOG_WARNING ("Invalid coin passed for /deposit\n");
GNUNET_JSON_parse_free (spec);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_UNAUTHORIZED,
TALER_EC_EXCHANGE_DENOMINATION_SIGNATURE_INVALID,
NULL))
? GNUNET_NO : GNUNET_SYSERR;
}
}
{
MHD_RESULT mhd_ret = MHD_NO;
enum GNUNET_DB_QueryStatus qs;
/* make sure coin is 'known' in database */
for (unsigned int tries = 0; tries<MAX_TRANSACTION_COMMIT_RETRIES; tries++)
{
qs = TEH_make_coin_known (&deposit.coin,
connection,
&pcc.known_coin_id,
&mhd_ret);
/* no transaction => no serialization failures should be possible */
if (GNUNET_DB_STATUS_SOFT_ERROR != qs)
break;
}
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
{
GNUNET_break (0);
return (MHD_YES ==
TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_COMMIT_FAILED,
"make_coin_known"))
? GNUNET_NO : GNUNET_SYSERR;
}
if (qs < 0)
return (MHD_YES == mhd_ret) ? GNUNET_NO : GNUNET_SYSERR;
}
return GNUNET_OK;
}
MHD_RESULT
TEH_handler_purses_create (struct MHD_Connection *connection,
const struct
TALER_PurseContractPublicKeyP *purse_pub,
const json_t *root)
{
struct PurseCreateContext pcc = {
.purse_pub = purse_pub,
.exchange_timestamp = GNUNET_TIME_timestamp_get ();
};
json_t *deposits;
json_t *deposit;
unsigned int idx;
struct GNUNET_JSON_Specification spec[] = {
TALER_JSON_spec_amount ("amount",
TEH_currency,
&pcc.amount),
GNUNET_JSON_spec_uint32 ("min_age",
&pcc.min_age),
GNUNET_JSON_spec_mark_optional (
GNUNET_JSON_spec_var_size ("econtract",
&pcc.econtract,
&pcc.ecotract_size)),
GNUNET_JSON_spec_fixed_auto ("contract_pub",
&pcc.contract_pub),
GNUNET_JSON_spec_fixed_auto ("merge_pub",
&pcc.merge_pub),
GNUNET_JSON_spec_fixed_auto ("purse_sig",
&pcc.purse_sig),
GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
&pcc.h_contract_terms),
GNUNET_JSON_spec_json ("deposits",
&deposits),
GNUNET_JSON_spec_timestamp ("purse_expiration",
&pcc.purse_expiration),
GNUNET_JSON_spec_end ()
};
{
enum GNUNET_GenericReturnValue res;
res = TALER_MHD_parse_json_data (connection,
root,
spec);
if (GNUNET_SYSERR == res)
{
GNUNET_break (0);
return MHD_NO; /* hard failure */
}
if (GNUNET_NO == res)
{
GNUNET_break_op (0);
return MHD_YES; /* failure */
}
}
if (GNUNET_TIME_timestamp_cmp (pcc.purse_expiration,
<,
pcc.exchange_timestamp))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_PURSE_CREATE_EXPIRATION_BEFORE_NOW,
NULL);
}
if (GNUNET_TIME_absolute_is_never (pcc.purse_expiration.abs_time))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_PURSE_CREATE_EXPIRATION_IS_NEVER,
NULL);
}
pcc.num_coins = json_array_size (deposits);
if ( (0 == pcc.num_coins) ||
(pcc.num_coins > TALER_MAX_FRESH_COINS) )
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_GENERIC_PARAMETER_MALFORMED,
"deposits");
}
/* parse deposits */
pcc.coins = GNUNET_new_array (struct Coin,
pcc.num_coins);
json_array_foreach (deposits, idx, deposit)
{
enum GNUNET_GenericReturnValue res;
struct Coin *coin = &pcc.coins[idx];
res = parse_coin (connection,
&pcc,
coin,
deposit);
if (GNUNET_OK != res)
{
GNUNET_JSON_parse_free (spec);
GNUNET_free (pcc.coins);
return (GNUNET_NO == res) ? MHD_YES : MHD_NO;
}
}
// FIXME: get purse_fee!
if (0 < TALER_amount_cmp (&purse_fee,
&pcc.deposit_total))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
GNUNET_free (pcc.coins);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_CREATE_PURSE_NEGATIVE_VALUE_AFTER_FEE,
NULL);
}
TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_EDDSA]++;
if (GNUNET_OK !=
TALER_wallet_purse_create_verify (&pcc.purse_expiration,
&pcc.h_contract_terms,
&pcc.merge_pub,
pcc.min_age,
&pcc.amount,
&pcc.purse_pub,
&pcc.purse_sig))
{
TALER_LOG_WARNING ("Invalid signature on /purses/$PID/create request\n");
GNUNET_JSON_parse_free (spec);
GNUNET_free (pcc.coins);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_UNAUTHORIZED,
TALER_EC_EXCHANGE_PURSE_CREATE_COIN_SIGNATURE_INVALID,
NULL);
}
if (GNUNET_SYSERR ==
TEH_plugin->preflight (TEH_plugin->cls))
{
GNUNET_break (0);
GNUNET_free (pcc.coins);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_START_FAILED,
"preflight failure");
}
/* execute transaction */
{
MHD_RESULT mhd_ret;
if (GNUNET_OK !=
TEH_DB_run_transaction (connection,
"execute purse create",
TEH_MT_REQUEST_PURSE_CREATE,
&mhd_ret,
&create_transaction,
&pcc))
{
GNUNET_JSON_parse_free (spec);
GNUNET_free (pcc.coins);
return mhd_ret;
}
}
/* generate regular response */
{
MHD_RESULT res;
res = reply_create_success (connection,
&pcc);
GNUNET_free (pcc.coins);
GNUNET_JSON_parse_free (spec);
return res;
}
}
/* end of taler-exchange-httpd_purses_create.c */

2
src/include/taler_crypto_lib.h
View File

@ -29,7 +29,7 @@
/**
* Maximum number of fresh coins we allow per refresh operation.
* Maximum number of coins we allow per operation.
*/
#define TALER_MAX_FRESH_COINS 256

23
src/include/taler_exchange_service.h
View File

@ -3985,10 +3985,16 @@ struct TALER_EXCHANGE_ContractGetResponse
/**
* Full HTTP response.
*/
struct TALER_EXCHANGE_HttpResponse *hr;
struct TALER_EXCHANGE_HttpResponse hr;
/**
* Details depending on the HTTP status code.
*/
union
{
/**
* Information returned on #MHD_HTTP_OK.
*/
struct
{
@ -4000,13 +4006,13 @@ struct TALER_EXCHANGE_ContractGetResponse
/**
* This is a request for payment.
*/
TALER_EXCHANGE_CONTRACT_PAYMENT_REQUEST,
TALER_EXCHANGE_CONTRACT_PAYMENT_REQUEST = 0,
/**
* This is a payment, the receiver needs to
* accepts the terms.
*/
TALER_EXCHANGE_CONTRACT_PAYMENT_OFFER
TALER_EXCHANGE_CONTRACT_PAYMENT_OFFER = 1
} type;
/**
@ -4026,7 +4032,7 @@ struct TALER_EXCHANGE_ContractGetResponse
} keys;
/**
* Total value of the purse.
* Total value of the contract/purse.
*/
struct TALER_Amount amount;
@ -4046,6 +4052,7 @@ struct TALER_EXCHANGE_ContractGetResponse
struct GNUNET_TIME_Timestamp purse_expiration;
} success;
} details;
};
@ -4105,7 +4112,7 @@ struct TALER_EXCHANGE_PurseGetResponse
/**
* Full HTTP response.
*/
struct TALER_EXCHANGE_HttpResponse *hr;
struct TALER_EXCHANGE_HttpResponse hr;
/**
* Details depending on the HTTP status.
@ -4327,7 +4334,7 @@ struct TALER_EXCHANGE_AccountMergeResponse
/**
* Full HTTP response.
*/
struct TALER_EXCHANGE_HttpResponse *hr;
struct TALER_EXCHANGE_HttpResponse hr;
/**
* Details depending on the HTTP status.
@ -4411,7 +4418,7 @@ struct TALER_EXCHANGE_PurseCreateMergeResponse
/**
* Full HTTP response.
*/
struct TALER_EXCHANGE_HttpResponse *hr;
struct TALER_EXCHANGE_HttpResponse hr;
/**
* Details depending on the HTTP status.
@ -4498,7 +4505,7 @@ struct TALER_EXCHANGE_PurseDepositResponse
/**
* Full HTTP response.
*/
struct TALER_EXCHANGE_HttpResponse *hr;
struct TALER_EXCHANGE_HttpResponse hr;
/**
* Details depending on the HTTP status.

12
src/lib/exchange_api_purse_create_with_deposit.c
View File

@ -212,6 +212,7 @@ TALER_EXCHANGE_purse_create_with_deposit (
json_t *deposit_arr;
CURL *eh;
struct TALER_PurseMergePublicKeyP merge_pub;
struct TALER_PurseContractSignatureP purse_sig;
struct TALER_PurseContractPublicKeyP purse_pub;
struct TALER_ContractDiffiePublicP contract_pub;
struct TALER_PrivateContractHashP h_contract_terms;
@ -335,6 +336,13 @@ TALER_EXCHANGE_purse_create_with_deposit (
jdeposit));
}
GNUNET_free (url);
TALER_wallet_purse_create_sign (purse_expiration,
&h_contract_terms,
&merge_pub,
min_age,
&purse_value_after_fees,
purse_priv,
&purse_sig);
{
void *econtract = NULL;
size_t econtract_size = 0;
@ -357,10 +365,14 @@ TALER_EXCHANGE_purse_create_with_deposit (
econtract_size)),
GNUNET_JSON_pack_data_auto ("contract_pub",
&contract_pub),
GNUNET_JSON_pack_data_auto ("purse_sig",
&purse_sig),
GNUNET_JSON_pack_data_auto ("merge_pub",
&merge_pub),
GNUNET_JSON_pack_data_auto ("h_contract_terms",
&h_contract_terms),
GNUNET_JSON_pack_timestamp ("purse_expiration",
purse_expiration),
GNUNET_JSON_pack_array_steal ("deposits",
deposit_arr));
GNUNET_free (econtract);