diff options
| -rw-r--r-- | src/auditor/taler-auditor.c | 201 |
1 files changed, 147 insertions, 54 deletions
diff --git a/src/auditor/taler-auditor.c b/src/auditor/taler-auditor.c index 1dd9a8748..c6b0fbf8d 100644 --- a/src/auditor/taler-auditor.c +++ b/src/auditor/taler-auditor.c @@ -23,9 +23,6 @@ * the wire transfers from the bank. This needs to be checked separately! * - Similarly, we do not check that the outgoing wire transfers match those * given in the 'wire_out' table. This needs to be checked separately! - * - * TODO: - * - FIXME: do proper transaction history check in #check_transaction_history() */ #include "platform.h" #include <gnunet/gnunet_util_lib.h> @@ -2002,16 +1999,17 @@ struct WireCheckContext /** * Check coin's transaction history for plausibility. Does NOT check - * the signatures (those are checked independently), but does check - * that the amounts add up to the picture claimed by the aggregation table. + * the signatures (those are checked independently), but does calculate + * the amounts for the aggregation table and checks that the total + * claimed coin value is within the value of the coin's denomination. * * @param coin_pub public key of the coin (for reporting) * @param h_proposal_data hash of the proposal for which we calculate the amount * @param merchant_pub public key of the merchant (who is allowed to issue refunds) * @param dki denomination information about the coin * @param tl_head head of transaction history to verify - * @param[out] final amount the coin contributes to the transaction - * @param[out] final fees the exchange charged for the transaction + * @param[out] merchant_gain amount the coin contributes to the wire transfer to the merchant + * @param[out] merchant_fees fees the exchange charged the merchant for the transaction(s) * @return #GNUNET_OK on success, #GNUNET_SYSERR on error */ static int @@ -2020,12 +2018,14 @@ check_transaction_history (const struct TALER_CoinSpendPublicKeyP *coin_pub, const struct TALER_MerchantPublicKeyP *merchant_pub, const struct TALER_EXCHANGEDB_DenominationKeyInformationP *dki, const struct TALER_EXCHANGEDB_TransactionList *tl_head, - struct TALER_Amount *final_expenditures, - struct TALER_Amount *final_fees) + struct TALER_Amount *merchant_gain, + struct TALER_Amount *merchant_fees) { struct TALER_Amount expenditures; struct TALER_Amount refunds; - struct TALER_Amount fees; + struct TALER_Amount spent; + struct TALER_Amount value; + struct TALER_Amount merchant_loss; GNUNET_assert (NULL != tl_head); TALER_amount_get_zero (currency, @@ -2033,16 +2033,22 @@ check_transaction_history (const struct TALER_CoinSpendPublicKeyP *coin_pub, TALER_amount_get_zero (currency, &refunds); TALER_amount_get_zero (currency, - &fees); + merchant_gain); + TALER_amount_get_zero (currency, + merchant_fees); + TALER_amount_get_zero (currency, + &merchant_loss); + /* Go over transaction history to compute totals; note that we do not + know the order, so instead of subtracting we compute positive + (deposit, melt) and negative (refund) values separately here, + and then subtract the negative from the positive after the loop. */ for (const struct TALER_EXCHANGEDB_TransactionList *tl = tl_head;NULL != tl;tl = tl->next) { const struct TALER_Amount *amount_with_fee; const struct TALER_Amount *fee; const struct TALER_AmountNBO *fee_dki; - struct TALER_Amount *add_to; struct TALER_Amount tmp; - add_to = NULL; // FIXME: // - for refunds/deposits that apply to this merchant and this contract // we need to update the total expenditures/refunds/fees @@ -2053,80 +2059,167 @@ check_transaction_history (const struct TALER_CoinSpendPublicKeyP *coin_pub, amount_with_fee = &tl->details.deposit->amount_with_fee; fee = &tl->details.deposit->deposit_fee; fee_dki = &dki->properties.fee_deposit; - add_to = &expenditures; + if (GNUNET_OK != + TALER_amount_add (&expenditures, + &expenditures, + amount_with_fee)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + /* Check if this deposit is within the remit of the aggregation + we are investigating, if so, include it in the totals. */ + if ( (0 == memcmp (merchant_pub, + &tl->details.deposit->merchant_pub, + sizeof (struct TALER_MerchantPublicKeyP))) && + (0 == memcmp (h_proposal_data, + &tl->details.deposit->h_proposal_data, + sizeof (struct GNUNET_HashCode))) ) + { + struct TALER_Amount amount_without_fee; + + if (GNUNET_OK != + TALER_amount_subtract (&amount_without_fee, + amount_with_fee, + fee)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + if (GNUNET_OK != + TALER_amount_add (merchant_gain, + merchant_gain, + &amount_without_fee)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + if (GNUNET_OK != + TALER_amount_add (merchant_fees, + merchant_fees, + fee)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + } break; case TALER_EXCHANGEDB_TT_REFRESH_MELT: amount_with_fee = &tl->details.melt->amount_with_fee; fee = &tl->details.melt->melt_fee; fee_dki = &dki->properties.fee_refresh; - add_to = &expenditures; + if (GNUNET_OK != + TALER_amount_add (&expenditures, + &expenditures, + amount_with_fee)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } break; case TALER_EXCHANGEDB_TT_REFUND: amount_with_fee = &tl->details.refund->refund_amount; fee = &tl->details.refund->refund_fee; fee_dki = &dki->properties.fee_refund; - add_to = &refunds; - // FIXME: where do we check that the refund(s) - // of the coin match the deposit(s) of the coin (by merchant, timestamp, etc.)? + if (GNUNET_OK != + TALER_amount_add (&refunds, + &refunds, + amount_with_fee)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + if (GNUNET_OK != + TALER_amount_add (&expenditures, + &expenditures, + fee)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + /* Check if this refund is within the remit of the aggregation + we are investigating, if so, include it in the totals. */ + if ( (0 == memcmp (merchant_pub, + &tl->details.refund->merchant_pub, + sizeof (struct TALER_MerchantPublicKeyP))) && + (0 == memcmp (h_proposal_data, + &tl->details.refund->h_proposal_data, + sizeof (struct GNUNET_HashCode))) ) + { + if (GNUNET_OK != + TALER_amount_add (&merchant_loss, + &merchant_loss, + amount_with_fee)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + if (GNUNET_OK != + TALER_amount_add (merchant_fees, + merchant_fees, + fee)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + } break; } - GNUNET_assert (NULL != add_to); /* check switch was exhaustive */ - if (GNUNET_OK != - TALER_amount_add (add_to, - add_to, - amount_with_fee)) - { - /* overflow in history already!? inconceivable! Bad DB! */ - GNUNET_break (0); - report_coin_inconsistency (coin_pub, - add_to, - amount_with_fee, - "could not add coin's contribution to total"); - return GNUNET_SYSERR; - } + + /* Check that the fees given in the transaction list and in dki match */ TALER_amount_ntoh (&tmp, fee_dki); if (0 != TALER_amount_cmp (&tmp, fee)) { - /* Disagreement in fee structure within DB! */ - GNUNET_break (0); - report_coin_inconsistency (coin_pub, - &tmp, - fee, - "coin's fee in transaction and in denomination data differ"); - return GNUNET_SYSERR; - } - if (GNUNET_OK != - TALER_amount_add (&fees, - &fees, - fee)) - { - /* overflow in fee total? inconceivable! Bad DB! */ + /* Disagreement in fee structure within DB, should be impossible! */ GNUNET_break (0); - report_coin_inconsistency (coin_pub, - fee, - &fees, - "could not add coin's fee to total fees"); return GNUNET_SYSERR; } } /* for 'tl' */ - /* Finally, calculate total balance change, i.e. expenditures minus refunds */ + /* Calculate total balance change, i.e. expenditures minus refunds */ if (GNUNET_SYSERR == - TALER_amount_subtract (final_expenditures, + TALER_amount_subtract (&spent, &expenditures, &refunds)) { - /* refunds above expenditures? inconceivable! Bad DB! */ - GNUNET_break (0); + /* refunds above expenditures? Bad! */ report_coin_inconsistency (coin_pub, &expenditures, &refunds, "could not subtract refunded amount from expenditures"); return GNUNET_SYSERR; } + + /* Now check that 'spent' is less or equal than total coin value */ + TALER_amount_ntoh (&value, + &dki->properties.value); + if (1 == TALER_amount_cmp (&spent, + &value)) + { + /* spent > value */ + report_coin_inconsistency (coin_pub, + &spent, + &value, + "accepted deposits (minus refunds) exceeds denomination value"); + return GNUNET_SYSERR; + } + + /* Finally, update @a merchant_gain by subtracting what he "lost" from refunds */ + if (GNUNET_SYSERR == + TALER_amount_subtract (merchant_gain, + merchant_gain, + &merchant_loss)) + { + /* refunds above deposits? Bad! */ + report_coin_inconsistency (coin_pub, + merchant_gain, + &merchant_loss, + "merchant was granted more refunds than he deposited"); + return GNUNET_SYSERR; + } return GNUNET_OK; } |