/*
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
*/
/**
* @file taler-exchange-httpd_reserves_purse.c
* @brief Handle /reserves/$RID/purse 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
#include
#include
#include
#include
#include "taler_json_lib.h"
#include "taler_kyclogic_lib.h"
#include "taler_mhd_lib.h"
#include "taler-exchange-httpd_reserves_purse.h"
#include "taler-exchange-httpd_responses.h"
#include "taler_exchangedb_lib.h"
#include "taler-exchange-httpd_keys.h"
/**
* Closure for #purse_transaction.
*/
struct ReservePurseContext
{
/**
* Public key of the reserve we are creating a purse for.
*/
const struct TALER_ReservePublicKeyP *reserve_pub;
/**
* Fees for the operation.
*/
const struct TEH_GlobalFee *gf;
/**
* Signature of the reserve affirming the merge.
*/
struct TALER_ReserveSignatureP reserve_sig;
/**
* Purse fee the client is willing to pay.
*/
struct TALER_Amount purse_fee;
/**
* Total amount already put into the purse.
*/
struct TALER_Amount deposit_total;
/**
* Merge time.
*/
struct GNUNET_TIME_Timestamp merge_timestamp;
/**
* Our current time.
*/
struct GNUNET_TIME_Timestamp exchange_timestamp;
/**
* Details about an encrypted contract, if any.
*/
struct TALER_EncryptedContract econtract;
/**
* Merge key for the purse.
*/
struct TALER_PurseMergePublicKeyP merge_pub;
/**
* Merge affirmation by the @e merge_pub.
*/
struct TALER_PurseMergeSignatureP merge_sig;
/**
* Signature of the client affiming this request.
*/
struct TALER_PurseContractSignatureP purse_sig;
/**
* Fundamental details about the purse.
*/
struct TEH_PurseDetails pd;
/**
* Hash of the @e payto_uri.
*/
struct TALER_PaytoHashP h_payto;
/**
* KYC status of the operation.
*/
struct TALER_EXCHANGEDB_KycStatus kyc;
/**
* Minimum age for deposits into this purse.
*/
uint32_t min_age;
/**
* Flags for the operation.
*/
enum TALER_WalletAccountMergeFlags flags;
/**
* Do we lack an @e econtract?
*/
bool no_econtract;
};
/**
* Function called to iterate over KYC-relevant
* transaction amounts for a particular time range.
* Called within a database transaction, so must
* not start a new one.
*
* @param cls a `struct ReservePurseContext`
* @param limit maximum time-range for which events
* should be fetched (timestamp in the past)
* @param cb function to call on each event found,
* events must be returned in reverse chronological
* order
* @param cb_cls closure for @a cb
*/
static void
amount_iterator (void *cls,
struct GNUNET_TIME_Absolute limit,
TALER_EXCHANGEDB_KycAmountCallback cb,
void *cb_cls)
{
struct ReservePurseContext *rpc = cls;
enum GNUNET_DB_QueryStatus qs;
cb (cb_cls,
&rpc->deposit_total,
GNUNET_TIME_absolute_get ());
qs = TEH_plugin->select_merge_amounts_for_kyc_check (
TEH_plugin->cls,
&rpc->h_payto,
limit,
cb,
cb_cls);
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Got %d additional transactions for this merge and limit %llu\n",
qs,
(unsigned long long) limit.abs_value_us);
GNUNET_break (qs >= 0);
}
/**
* Execute database transaction for /reserves/$PID/purse. 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 ReservePurseContext`
* @param connection MHD request context
* @param[out] mhd_ret set to MHD status on error
* @return transaction status
*/
static enum GNUNET_DB_QueryStatus
purse_transaction (void *cls,
struct MHD_Connection *connection,
MHD_RESULT *mhd_ret)
{
struct ReservePurseContext *rpc = cls;
enum GNUNET_DB_QueryStatus qs;
const char *required;
qs = TALER_KYCLOGIC_kyc_test_required (
TALER_KYCLOGIC_KYC_TRIGGER_P2P_RECEIVE,
&rpc->h_payto,
TEH_plugin->select_satisfied_kyc_processes,
TEH_plugin->cls,
&amount_iterator,
rpc,
&required);
if (qs < 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
GNUNET_break (0);
*mhd_ret =
TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"kyc_test_required");
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (NULL != required)
{
rpc->kyc.ok = false;
return TEH_plugin->insert_kyc_requirement_for_account (
TEH_plugin->cls,
required,
&rpc->h_payto,
&rpc->kyc.requirement_row);
}
rpc->kyc.ok = true;
{
bool in_conflict = true;
/* 1) store purse */
qs = TEH_plugin->insert_purse_request (
TEH_plugin->cls,
&rpc->pd.purse_pub,
&rpc->merge_pub,
rpc->pd.purse_expiration,
&rpc->pd.h_contract_terms,
rpc->min_age,
rpc->flags,
&rpc->purse_fee,
&rpc->pd.target_amount,
&rpc->purse_sig,
&in_conflict);
if (qs < 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
GNUNET_break (0);
*mhd_ret =
TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_STORE_FAILED,
"insert purse request");
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
return qs;
if (in_conflict)
{
struct TALER_PurseMergePublicKeyP merge_pub;
struct GNUNET_TIME_Timestamp purse_expiration;
struct TALER_PrivateContractHashP h_contract_terms;
struct TALER_Amount target_amount;
struct TALER_Amount balance;
struct TALER_PurseContractSignatureP purse_sig;
uint32_t min_age;
TEH_plugin->rollback (TEH_plugin->cls);
qs = TEH_plugin->get_purse_request (
TEH_plugin->cls,
&rpc->pd.purse_pub,
&merge_pub,
&purse_expiration,
&h_contract_terms,
&min_age,
&target_amount,
&balance,
&purse_sig);
if (qs <= 0)
{
GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR != qs);
GNUNET_break (0 != qs);
TALER_LOG_WARNING ("Failed to fetch purse information from database\n");
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"select purse request");
return GNUNET_DB_STATUS_HARD_ERROR;
}
*mhd_ret
= TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_CONFLICT,
TALER_JSON_pack_ec (
TALER_EC_EXCHANGE_RESERVES_PURSE_CREATE_CONFLICTING_META_DATA),
TALER_JSON_pack_amount ("amount",
&target_amount),
GNUNET_JSON_pack_uint64 ("min_age",
min_age),
GNUNET_JSON_pack_timestamp ("purse_expiration",
purse_expiration),
GNUNET_JSON_pack_data_auto ("purse_sig",
&purse_sig),
GNUNET_JSON_pack_data_auto ("h_contract_terms",
&h_contract_terms),
GNUNET_JSON_pack_data_auto ("merge_pub",
&merge_pub));
return GNUNET_DB_STATUS_HARD_ERROR;
}
}
/* 2) create purse with reserve (and debit reserve for purse creation!) */
{
bool in_conflict = true;
bool insufficient_funds = true;
bool no_reserve = true;
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Creating purse with flags %d\n",
rpc->flags);
qs = TEH_plugin->do_reserve_purse (
TEH_plugin->cls,
&rpc->pd.purse_pub,
&rpc->merge_sig,
rpc->merge_timestamp,
&rpc->reserve_sig,
(TALER_WAMF_MODE_CREATE_FROM_PURSE_QUOTA
== rpc->flags)
? NULL
: &rpc->gf->fees.purse,
rpc->reserve_pub,
&in_conflict,
&no_reserve,
&insufficient_funds);
if (qs < 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
TALER_LOG_WARNING (
"Failed to store purse merge information in database\n");
*mhd_ret =
TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_STORE_FAILED,
"do reserve purse");
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (in_conflict)
{
/* same purse already merged into a different reserve!? */
struct TALER_PurseContractPublicKeyP purse_pub;
struct TALER_PurseMergeSignatureP merge_sig;
struct GNUNET_TIME_Timestamp merge_timestamp;
char *partner_url;
struct TALER_ReservePublicKeyP reserve_pub;
TEH_plugin->rollback (TEH_plugin->cls);
qs = TEH_plugin->select_purse_merge (
TEH_plugin->cls,
&purse_pub,
&merge_sig,
&merge_timestamp,
&partner_url,
&reserve_pub);
if (qs <= 0)
{
GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR != qs);
GNUNET_break (0 != qs);
TALER_LOG_WARNING (
"Failed to fetch purse merge information from database\n");
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"select purse merge");
return GNUNET_DB_STATUS_HARD_ERROR;
}
*mhd_ret
= TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_CONFLICT,
TALER_JSON_pack_ec (
TALER_EC_EXCHANGE_RESERVES_PURSE_MERGE_CONFLICTING_META_DATA),
GNUNET_JSON_pack_string ("partner_url",
NULL == partner_url
? TEH_base_url
: partner_url),
GNUNET_JSON_pack_timestamp ("merge_timestamp",
merge_timestamp),
GNUNET_JSON_pack_data_auto ("merge_sig",
&merge_sig),
GNUNET_JSON_pack_data_auto ("reserve_pub",
&reserve_pub));
GNUNET_free (partner_url);
return GNUNET_DB_STATUS_HARD_ERROR;
}
if ( (no_reserve) &&
( (TALER_WAMF_MODE_CREATE_FROM_PURSE_QUOTA
== rpc->flags) ||
(! TALER_amount_is_zero (&rpc->gf->fees.purse)) ) )
{
*mhd_ret
= TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_NOT_FOUND,
TALER_JSON_pack_ec (
TALER_EC_EXCHANGE_GENERIC_RESERVE_UNKNOWN));
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (insufficient_funds)
{
*mhd_ret
= TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_CONFLICT,
TALER_JSON_pack_ec (
TALER_EC_EXCHANGE_RESERVES_PURSE_CREATE_INSUFFICIENT_FUNDS));
return GNUNET_DB_STATUS_HARD_ERROR;
}
}
/* 3) if present, persist contract */
if (! rpc->no_econtract)
{
bool in_conflict = true;
qs = TEH_plugin->insert_contract (TEH_plugin->cls,
&rpc->pd.purse_pub,
&rpc->econtract,
&in_conflict);
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 purse contract");
return GNUNET_DB_STATUS_HARD_ERROR;
}
if (in_conflict)
{
struct TALER_EncryptedContract econtract;
struct GNUNET_HashCode h_econtract;
qs = TEH_plugin->select_contract_by_purse (
TEH_plugin->cls,
&rpc->pd.purse_pub,
&econtract);
if (qs <= 0)
{
if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
return qs;
GNUNET_break (0 != qs);
TALER_LOG_WARNING (
"Failed to store fetch contract information from database\n");
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"select contract");
return GNUNET_DB_STATUS_HARD_ERROR;
}
GNUNET_CRYPTO_hash (econtract.econtract,
econtract.econtract_size,
&h_econtract);
*mhd_ret
= TALER_MHD_REPLY_JSON_PACK (
connection,
MHD_HTTP_CONFLICT,
TALER_JSON_pack_ec (
TALER_EC_EXCHANGE_PURSE_ECONTRACT_CONFLICTING_META_DATA),
GNUNET_JSON_pack_data_auto ("h_econtract",
&h_econtract),
GNUNET_JSON_pack_data_auto ("econtract_sig",
&econtract.econtract_sig),
GNUNET_JSON_pack_data_auto ("contract_pub",
&econtract.contract_pub));
GNUNET_free (econtract.econtract);
return GNUNET_DB_STATUS_HARD_ERROR;
}
}
return qs;
}
MHD_RESULT
TEH_handler_reserves_purse (
struct TEH_RequestContext *rc,
const struct TALER_ReservePublicKeyP *reserve_pub,
const json_t *root)
{
struct MHD_Connection *connection = rc->connection;
struct ReservePurseContext rpc = {
.reserve_pub = reserve_pub,
.exchange_timestamp = GNUNET_TIME_timestamp_get ()
};
bool no_purse_fee = true;
struct GNUNET_JSON_Specification spec[] = {
TALER_JSON_spec_amount ("purse_value",
TEH_currency,
&rpc.pd.target_amount),
GNUNET_JSON_spec_uint32 ("min_age",
&rpc.min_age),
GNUNET_JSON_spec_mark_optional (
TALER_JSON_spec_amount ("purse_fee",
TEH_currency,
&rpc.purse_fee),
&no_purse_fee),
GNUNET_JSON_spec_mark_optional (
TALER_JSON_spec_econtract ("econtract",
&rpc.econtract),
&rpc.no_econtract),
GNUNET_JSON_spec_fixed_auto ("merge_pub",
&rpc.merge_pub),
GNUNET_JSON_spec_fixed_auto ("merge_sig",
&rpc.merge_sig),
GNUNET_JSON_spec_fixed_auto ("reserve_sig",
&rpc.reserve_sig),
GNUNET_JSON_spec_fixed_auto ("purse_pub",
&rpc.pd.purse_pub),
GNUNET_JSON_spec_fixed_auto ("purse_sig",
&rpc.purse_sig),
GNUNET_JSON_spec_fixed_auto ("h_contract_terms",
&rpc.pd.h_contract_terms),
GNUNET_JSON_spec_timestamp ("merge_timestamp",
&rpc.merge_timestamp),
GNUNET_JSON_spec_timestamp ("purse_expiration",
&rpc.pd.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 */
}
}
{
char *payto_uri;
payto_uri = TALER_reserve_make_payto (TEH_base_url,
reserve_pub);
TALER_payto_hash (payto_uri,
&rpc.h_payto);
TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_EDDSA]++;
if (GNUNET_OK !=
TALER_wallet_purse_merge_verify (payto_uri,
rpc.merge_timestamp,
&rpc.pd.purse_pub,
&rpc.merge_pub,
&rpc.merge_sig))
{
MHD_RESULT ret;
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
ret = TALER_MHD_reply_with_error (
connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_EXCHANGE_RESERVES_PURSE_MERGE_SIGNATURE_INVALID,
payto_uri);
GNUNET_free (payto_uri);
return ret;
}
GNUNET_free (payto_uri);
}
GNUNET_assert (GNUNET_OK ==
TALER_amount_set_zero (TEH_currency,
&rpc.deposit_total));
if (GNUNET_TIME_timestamp_cmp (rpc.pd.purse_expiration,
<,
rpc.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_RESERVES_PURSE_EXPIRATION_BEFORE_NOW,
NULL);
}
if (GNUNET_TIME_absolute_is_never (rpc.pd.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_RESERVES_PURSE_EXPIRATION_IS_NEVER,
NULL);
}
{
struct TEH_KeyStateHandle *keys;
keys = TEH_keys_get_state ();
if (NULL == keys)
{
GNUNET_break (0);
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_EXCHANGE_GENERIC_KEYS_MISSING,
NULL);
}
rpc.gf = TEH_keys_global_fee_by_time (keys,
rpc.exchange_timestamp);
}
if (NULL == rpc.gf)
{
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
"Cannot purse purse: global fees not configured!\n");
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_EXCHANGE_GENERIC_GLOBAL_FEES_MISSING,
NULL);
}
if (no_purse_fee)
{
rpc.flags = TALER_WAMF_MODE_CREATE_FROM_PURSE_QUOTA;
GNUNET_assert (GNUNET_OK ==
TALER_amount_set_zero (TEH_currency,
&rpc.purse_fee));
}
else
{
rpc.flags = TALER_WAMF_MODE_CREATE_WITH_PURSE_FEE;
if (-1 ==
TALER_amount_cmp (&rpc.purse_fee,
&rpc.gf->fees.purse))
{
/* rpc.purse_fee is below gf.fees.purse! */
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_EXCHANGE_RESERVES_PURSE_FEE_TOO_LOW,
TALER_amount2s (&rpc.gf->fees.purse));
}
}
TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_EDDSA]++;
if (GNUNET_OK !=
TALER_wallet_purse_create_verify (rpc.pd.purse_expiration,
&rpc.pd.h_contract_terms,
&rpc.merge_pub,
rpc.min_age,
&rpc.pd.target_amount,
&rpc.pd.purse_pub,
&rpc.purse_sig))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (
connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_EXCHANGE_PURSE_CREATE_SIGNATURE_INVALID,
NULL);
}
if (GNUNET_OK !=
TALER_wallet_account_merge_verify (rpc.merge_timestamp,
&rpc.pd.purse_pub,
rpc.pd.purse_expiration,
&rpc.pd.h_contract_terms,
&rpc.pd.target_amount,
&rpc.purse_fee,
rpc.min_age,
rpc.flags,
rpc.reserve_pub,
&rpc.reserve_sig))
{
GNUNET_break_op (0);
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (
connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_EXCHANGE_RESERVES_RESERVE_MERGE_SIGNATURE_INVALID,
NULL);
}
if ( (! rpc.no_econtract) &&
(GNUNET_OK !=
TALER_wallet_econtract_upload_verify (rpc.econtract.econtract,
rpc.econtract.econtract_size,
&rpc.econtract.contract_pub,
&rpc.pd.purse_pub,
&rpc.econtract.econtract_sig)) )
{
TALER_LOG_WARNING ("Invalid signature on /reserves/$PID/purse request\n");
GNUNET_JSON_parse_free (spec);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_FORBIDDEN,
TALER_EC_EXCHANGE_PURSE_ECONTRACT_SIGNATURE_INVALID,
NULL);
}
if (GNUNET_SYSERR ==
TEH_plugin->preflight (TEH_plugin->cls))
{
GNUNET_break (0);
GNUNET_JSON_parse_free (spec);
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 purse",
TEH_MT_REQUEST_RESERVE_PURSE,
&mhd_ret,
&purse_transaction,
&rpc))
{
GNUNET_JSON_parse_free (spec);
return mhd_ret;
}
}
if (! rpc.kyc.ok)
return TEH_RESPONSE_reply_kyc_required (connection,
&rpc.h_payto,
&rpc.kyc);
/* generate regular response */
{
MHD_RESULT res;
res = TEH_RESPONSE_reply_purse_created (connection,
rpc.exchange_timestamp,
&rpc.deposit_total,
&rpc.pd);
GNUNET_JSON_parse_free (spec);
return res;
}
}
/* end of taler-exchange-httpd_reserves_purse.c */