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latest commit before giving up on this branch

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Özgür Kesim 2023-03-04 12:18:01 +01:00
parent e36c6748bd
commit a39f83057f
Signed by: oec
GPG Key ID: 3D76A56D79EDD9D7
2 changed files with 153 additions and 69 deletions
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212
src/exchange/taler-exchange-httpd_age-withdraw_reveal.c
View File

@ -52,26 +52,32 @@ struct AgeRevealContext
uint32_t num_coins;
/**
* TODO:oec num_coins denoms
* #num_coins hashes of the denominations to withdraw from.
* Those must support age restriction.
*/
struct TALER_DenominationHashP *denoms_h;
/**
* TODO:oec num_coins blinded coins
* #num_coins hashes of blinded coins.
*/
struct TALER_BlindedCoinHashP *coin_evs;
/**
* TODO:oec num_coins*(kappa - 1) disclosed coins
* #num_coins*(kappa - 1) disclosed coins.
*/
struct GNUNET_CRYPTO_EddsaPrivateKey *disclosed_coins;
/**
* The data from the original age-withraw request. Will be retrieved from
* the DB via @a ach.
*/
struct TALER_EXCHANGEDB_AgeWithdrawCommitment age_withdraw_request;
};
/**
* Helper function to free resources in the context
*/
void
static void
age_reveal_context_free (struct AgeRevealContext *actx)
{
GNUNET_free (actx->denoms_h);
@ -81,24 +87,29 @@ age_reveal_context_free (struct AgeRevealContext *actx)
/**
* Handle a "/age-withdraw/$ACH/reveal request. Parses the given JSON
* ... TODO:oec:description
* Parse the json body of a "/age-withdraw/$ACH/reveal request. It extracts
* the denomination hashes, blinded coins and disclosed coins and allocates
* memory for those.
*
* @param connection The MHD connection to handle
* @param actx The context of the operation, only partially built at call time
* @param j_denoms_h Array of hashes of the denominations for the withdrawal, in JSON format
* @param j_coin_evs The blinded envelopes in JSON format for the coins that are not revealed and will be signed on success
* @param j_disclosed_coins The n*(kappa-1) disclosed coins' private keys in JSON format, from which all other attributes (age restriction, blinding, nonce) will be derived from
* @param[out] actx The context of the operation, only partially built at call time
* @param[out] mhd_mret The result if a reply is queued for MHD
* @return true on success, false on failure, with a reply already queued for MHD.
*/
MHD_RESULT
handle_age_withdraw_reveal_json (
static bool
parse_age_withdraw_reveal_json (
struct MHD_Connection *connection,
struct AgeRevealContext *actx,
const json_t *j_denoms_h,
const json_t *j_coin_evs,
const json_t *j_disclosed_coins)
const json_t *j_disclosed_coins,
struct AgeRevealContext *actx,
MHD_RESULT *mhd_ret)
{
MHD_RESULT mhd_ret = MHD_NO;
bool result = false;
/* Verify JSON-structure consistency */
{
@ -121,18 +132,18 @@ handle_age_withdraw_reveal_json (
error = "the size of array disclosed_coins must be "
TALER_CNC_KAPPA_MINUS_ONE_STR " times of the size of denoms_h";
else if (actx->num_coins > TALER_MAX_FRESH_COINS)
/**
* FIXME?: If the user had commited to more than the maximum coins allowed,
* the reserve has been charged, but now the user can not withdraw any money
* from it. How can the user get their money back?
**/
/* In violation of the protocol, the wallet committed to more than the
* maximum coins allowed */
error = "maximum number of coins that can be withdrawn has been exceeded";
if (NULL != error)
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
error);
{
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
error);
return result;
}
}
/* Parse denomination keys */
@ -157,13 +168,12 @@ handle_age_withdraw_reveal_json (
sizeof(msg),
"couldn't parse entry no. %d in array denoms_h",
idx + 1);
mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
msg);
goto EXIT;
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
msg);
goto CLEANUP;
}
};
}
@ -189,11 +199,11 @@ handle_age_withdraw_reveal_json (
sizeof(msg),
"couldn't parse entry no. %d in array coin_evs",
idx + 1);
mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
msg);
goto EXIT;
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
msg);
goto CLEANUP;
}
};
}
@ -221,30 +231,81 @@ handle_age_withdraw_reveal_json (
sizeof(msg),
"couldn't parse entry no. %d in array disclosed_coins",
idx + 1);
mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
msg);
goto EXIT;
*mhd_ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_GENERIC_PARAMETER_MALFORMED,
msg);
goto CLEANUP;
}
};
}
/* TODO:oec: find commitment */
/* TODO:oec: check validity of denoms */
/* TODO:oec: check amount total against denoms */
/* TODO:oec: compute the disclosed blinded coins */
/* TODO:oec: generate h_commitment_comp */
/* TODO:oec: compare h_commitment_comp against h_commitment */
/* TODO:oec: sign the coins */
/* TODO:oec: send response */
result = true;
*mhd_ret = MHD_YES;
/* TODO */
EXIT:
CLEANUP:
age_reveal_context_free (actx);
return mhd_ret;
return result;
}
/**
* Check if the request belongs to an existing age-withdraw request.
* If so, sets the age_withdraw object with the request data.
* Otherwise, it queues an appropriate MHD response.
*
* @param rc Request context
* @param ach Original commitment value sent with the age-withdraw request
* @param rpub Reserve public key used in the original age-withdraw request
* @param[out] age_withdraw Data from the original age-withdraw request
* @param[out] mhd The result if a reply is queued for MHD
* @return true if the withdraw request has been found,
* false if we did not find the request in the DB
*/
static bool
retrieve_original_commitment (
struct MHD_Connection *connection,
const struct TALER_AgeWithdrawCommitmentHashP *h_commitment,
const struct TALER_ReservePublicKeyP *reserve_pub,
struct TALER_EXCHANGEDB_AgeWithdrawCommitment *age_withdraw_request,
MHD_RESULT *mhd)
{
enum GNUNET_DB_QueryStatus qs;
qs = TEH_plugin->get_age_withdraw_info (TEH_plugin->cls,
reserve_pub,
h_commitment,
age_withdraw_request);
if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT != qs)
{
switch (qs)
{
case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS:
*mhd = TALER_MHD_reply_with_error (connection,
MHD_HTTP_NOT_FOUND,
TALER_EC_EXCHANGE_AGE_WITHDRAW_COMMITMENT_UNKNOWN,
NULL);
break;
case GNUNET_DB_STATUS_HARD_ERROR:
*mhd = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_DB_FETCH_FAILED,
"get_age_withdraw_info");
break;
case GNUNET_DB_STATUS_SOFT_ERROR:
default:
GNUNET_break (0); /* should be impossible */
*mhd = TALER_MHD_reply_with_error (connection,
MHD_HTTP_INTERNAL_SERVER_ERROR,
TALER_EC_GENERIC_INTERNAL_INVARIANT_FAILURE,
NULL);
}
return false;
}
return true;
}
@ -254,6 +315,7 @@ TEH_handler_age_withdraw_reveal (
const struct TALER_AgeWithdrawCommitmentHashP *ach,
const json_t *root)
{
MHD_RESULT res = MHD_NO;
struct AgeRevealContext actx = {0};
json_t *j_denoms_h;
json_t *j_coin_evs;
@ -270,33 +332,55 @@ TEH_handler_age_withdraw_reveal (
/* Parse JSON body*/
{
enum GNUNET_GenericReturnValue res;
enum GNUNET_GenericReturnValue ret;
res = TALER_MHD_parse_json_data (rc->connection,
ret = TALER_MHD_parse_json_data (rc->connection,
root,
spec);
if (GNUNET_OK != res)
if (GNUNET_OK != ret)
{
GNUNET_break_op (0);
return (GNUNET_SYSERR == res) ? MHD_NO : MHD_YES;
return (GNUNET_SYSERR == ret) ? MHD_NO : MHD_YES;
}
}
do {
/* Extract information from json for denominations, blinded and disclosed coins */
if (! parse_age_withdraw_reveal_json (rc->connection,
j_denoms_h,
j_coin_evs,
j_disclosed_coins,
&actx,
&res))
break;
/* handle reveal request */
{
MHD_RESULT res;
/* Find original commitment */
if (! retrieve_original_commitment (rc->connection,
&actx.ach,
&actx.reserve_pub,
&actx.age_withdraw_request,
&res))
break;
res = handle_age_withdraw_reveal_json (rc->connection,
&actx,
j_denoms_h,
j_coin_evs,
j_disclosed_coins);
/* Ensure validity of denoms */
if (! all_donimations_valid (rc->connection,
&actx.denoms_h,
/* Arg for denoms */
&res))
break;
GNUNET_JSON_parse_free (spec);
return res;
}
/* TODO:oec: check amount total against denoms */
/* TODO:oec: compute the disclosed blinded coins */
/* TODO:oec: generate h_commitment_comp */
/* TODO:oec: compare h_commitment_comp against h_commitment */
/* TODO:oec: sign the coins */
/* TODO:oec: send response */
} while(0);
age_reveal_context_free (&actx);
GNUNET_JSON_parse_free (spec);
return res;
}

10
src/exchange/taler-exchange-httpd_refreshes_reveal.c
View File

@ -511,11 +511,11 @@ resolve_refreshes_reveal_denominations (
}
}
old_dk = TEH_keys_denomination_by_hash2 (
ksh,
&rctx->melt.session.coin.denom_pub_hash,
connection,
&ret);
old_dk = TEH_keys_denomination_by_hash2 (ksh,
&rctx->melt.session.coin.
denom_pub_hash,
connection,
&ret);
if (NULL == old_dk)
return ret;