From 53e98c10cf5dcb06ad57cf30857f82c5e9434aa0 Mon Sep 17 00:00:00 2001 From: Christian Grothoff Date: Thu, 9 Aug 2018 22:30:35 +0200 Subject: add option for optimistic signing on withdraw (pre DB transaction) --- .../taler-exchange-httpd_reserve_withdraw.c | 68 ++++++++++++++++++++++ 1 file changed, 68 insertions(+) (limited to 'src/exchange/taler-exchange-httpd_reserve_withdraw.c') diff --git a/src/exchange/taler-exchange-httpd_reserve_withdraw.c b/src/exchange/taler-exchange-httpd_reserve_withdraw.c index 837d60375..2b127ce50 100644 --- a/src/exchange/taler-exchange-httpd_reserve_withdraw.c +++ b/src/exchange/taler-exchange-httpd_reserve_withdraw.c @@ -29,6 +29,14 @@ #include "taler-exchange-httpd_keystate.h" +/** + * Perform RSA signature before checking with the database? + * Reduces time spent in transaction, but may cause us to + * waste CPU time if DB check fails. + */ +#define OPTIMISTIC_SIGN 1 + + /** * Send reserve status information to client with the * message that we have insufficient funds for the @@ -172,6 +180,12 @@ withdraw_transaction (void *cls, enum GNUNET_DB_QueryStatus qs; struct TALER_DenominationSignature denom_sig; +#if OPTIMISTIC_SIGN + /* store away optimistic signature to protect + it from being overwritten by get_withdraw_info */ + denom_sig = wc->collectable.sig; + wc->collectable.sig.rsa_signature = NULL; +#endif qs = TEH_plugin->get_withdraw_info (TEH_plugin->cls, session, &wc->wsrd.h_coin_envelope, @@ -182,12 +196,20 @@ withdraw_transaction (void *cls, if (GNUNET_DB_STATUS_HARD_ERROR == qs) *mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection, TALER_EC_WITHDRAW_DB_FETCH_ERROR); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return qs; } /* Don't sign again if we have already signed the coin */ if (1 == qs) + { +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return GNUNET_DB_STATUS_SUCCESS_ONE_RESULT; + } GNUNET_assert (0 == qs); /* Check if balance is sufficient */ @@ -200,6 +222,9 @@ withdraw_transaction (void *cls, if (GNUNET_DB_STATUS_HARD_ERROR == qs) *mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection, TALER_EC_WITHDRAW_DB_FETCH_ERROR); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return qs; } if (NULL == rh) @@ -207,6 +232,9 @@ withdraw_transaction (void *cls, *mhd_ret = TEH_RESPONSE_reply_arg_unknown (connection, TALER_EC_WITHDRAW_RESERVE_UNKNOWN, "reserve_pub"); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return GNUNET_DB_STATUS_HARD_ERROR; } @@ -229,6 +257,9 @@ withdraw_transaction (void *cls, { *mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection, TALER_EC_WITHDRAW_AMOUNT_DEPOSITS_OVERFLOW); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return GNUNET_DB_STATUS_HARD_ERROR; } res |= 1; @@ -245,6 +276,9 @@ withdraw_transaction (void *cls, { *mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection, TALER_EC_WITHDRAW_AMOUNT_WITHDRAWALS_OVERFLOW); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return GNUNET_DB_STATUS_HARD_ERROR; } res |= 2; @@ -261,6 +295,9 @@ withdraw_transaction (void *cls, { *mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection, TALER_EC_WITHDRAW_AMOUNT_DEPOSITS_OVERFLOW); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return GNUNET_DB_STATUS_HARD_ERROR; } res |= 1; @@ -277,6 +314,9 @@ withdraw_transaction (void *cls, { *mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection, TALER_EC_WITHDRAW_AMOUNT_WITHDRAWALS_OVERFLOW); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return GNUNET_DB_STATUS_HARD_ERROR; } @@ -290,6 +330,9 @@ withdraw_transaction (void *cls, GNUNET_break (0); *mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection, TALER_EC_WITHDRAW_RESERVE_WITHOUT_WIRE_TRANSFER); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return GNUNET_DB_STATUS_HARD_ERROR; } if (0 == (res & 2)) @@ -308,6 +351,9 @@ withdraw_transaction (void *cls, GNUNET_break (0); /* database inconsistent */ *mhd_ret = TEH_RESPONSE_reply_internal_db_error (connection, TALER_EC_WITHDRAW_RESERVE_HISTORY_IMPOSSIBLE); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return GNUNET_DB_STATUS_HARD_ERROR; } @@ -319,12 +365,16 @@ withdraw_transaction (void *cls, rh); TEH_plugin->free_reserve_history (TEH_plugin->cls, rh); +#if OPTIMISTIC_SIGN + GNUNET_CRYPTO_rsa_signature_free (denom_sig.rsa_signature); +#endif return GNUNET_DB_STATUS_HARD_ERROR; } TEH_plugin->free_reserve_history (TEH_plugin->cls, rh); /* Balance is good, sign the coin! */ +#if !OPTIMISTIC_SIGN denom_sig.rsa_signature = GNUNET_CRYPTO_rsa_sign_blinded (wc->dki->denom_priv.rsa_private_key, wc->blinded_msg, @@ -337,6 +387,7 @@ withdraw_transaction (void *cls, "Internal error"); return GNUNET_DB_STATUS_HARD_ERROR; } +#endif TALER_amount_ntoh (&fee_withdraw, &wc->dki->issue.properties.fee_withdraw); wc->collectable.sig = denom_sig; @@ -482,6 +533,23 @@ TEH_RESERVE_handler_reserve_withdraw (struct TEH_RequestHandler *rh, "reserve_sig"); } +#if OPTIMISTIC_SIGN + /* Sign before transaction! */ + wc.collectable.sig.rsa_signature + = GNUNET_CRYPTO_rsa_sign_blinded (wc.dki->denom_priv.rsa_private_key, + wc.blinded_msg, + wc.blinded_msg_len); + if (NULL == wc.collectable.sig.rsa_signature) + { + GNUNET_break (0); + GNUNET_JSON_parse_free (spec); + TEH_KS_release (wc.key_state); + return TEH_RESPONSE_reply_internal_error (connection, + TALER_EC_WITHDRAW_SIGNATURE_FAILED, + "Internal error"); + } +#endif + if (GNUNET_OK != TEH_DB_run_transaction (connection, "run reserve withdraw", -- cgit v1.2.3