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-rw-r--r--src/lib/exchange_api_refresh.c1770
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diff --git a/src/lib/exchange_api_refresh.c b/src/lib/exchange_api_refresh.c
deleted file mode 100644
index eb26b7c15..000000000
--- a/src/lib/exchange_api_refresh.c
+++ /dev/null
@@ -1,1770 +0,0 @@
-/*
- This file is part of TALER
- Copyright (C) 2015-2020 Taler Systems SA
-
- TALER is free software; you can redistribute it and/or modify it under the
- terms of the GNU 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 General Public License for more details.
-
- You should have received a copy of the GNU General Public License along with
- TALER; see the file COPYING. If not, see
- <http://www.gnu.org/licenses/>
-*/
-/**
- * @file lib/exchange_api_refresh.c
- * @brief Implementation of the /refresh/melt+reveal requests of the exchange's HTTP API
- * @author Christian Grothoff
- */
-#include "platform.h"
-#include <jansson.h>
-#include <microhttpd.h> /* just for HTTP status codes */
-#include <gnunet/gnunet_util_lib.h>
-#include <gnunet/gnunet_json_lib.h>
-#include <gnunet/gnunet_curl_lib.h>
-#include "taler_json_lib.h"
-#include "taler_exchange_service.h"
-#include "exchange_api_handle.h"
-#include "taler_signatures.h"
-#include "exchange_api_curl_defaults.h"
-
-
-/* ********************* /refresh/ common ***************************** */
-
-/* structures for committing refresh data to disk before doing the
- network interaction(s) */
-
-GNUNET_NETWORK_STRUCT_BEGIN
-
-/**
- * Header of serialized information about a coin we are melting.
- */
-struct MeltedCoinP
-{
- /**
- * Private key of the coin.
- */
- struct TALER_CoinSpendPrivateKeyP coin_priv;
-
- /**
- * Amount this coin contributes to the melt, including fee.
- */
- struct TALER_AmountNBO melt_amount_with_fee;
-
- /**
- * The applicable fee for withdrawing a coin of this denomination
- */
- struct TALER_AmountNBO fee_melt;
-
- /**
- * The original value of the coin.
- */
- struct TALER_AmountNBO original_value;
-
- /**
- * Transfer private keys for each cut-and-choose dimension.
- */
- struct TALER_TransferPrivateKeyP transfer_priv[TALER_CNC_KAPPA];
-
- /**
- * Timestamp indicating when coins of this denomination become invalid.
- */
- struct GNUNET_TIME_AbsoluteNBO expire_deposit;
-
- /**
- * Size of the encoded public key that follows.
- */
- uint16_t pbuf_size;
-
- /**
- * Size of the encoded signature that follows.
- */
- uint16_t sbuf_size;
-
- /* Followed by serializations of:
- 1) struct TALER_DenominationPublicKey pub_key;
- 2) struct TALER_DenominationSignature sig;
- */
-};
-
-
-/**
- * Header of serialized data about a melt operation, suitable for
- * persisting it on disk.
- */
-struct MeltDataP
-{
-
- /**
- * Hash over the melting session.
- */
- struct TALER_RefreshCommitmentP rc;
-
- /**
- * Number of coins we are melting, in NBO
- */
- uint16_t num_melted_coins GNUNET_PACKED;
-
- /**
- * Number of coins we are creating, in NBO
- */
- uint16_t num_fresh_coins GNUNET_PACKED;
-
- /* Followed by serializations of:
- 1) struct MeltedCoinP melted_coins[num_melted_coins];
- 2) struct TALER_EXCHANGE_DenomPublicKey fresh_pks[num_fresh_coins];
- 3) TALER_CNC_KAPPA times:
- 3a) struct TALER_PlanchetSecretsP fresh_coins[num_fresh_coins];
- */
-};
-
-
-GNUNET_NETWORK_STRUCT_END
-
-
-/**
- * Information about a coin we are melting.
- */
-struct MeltedCoin
-{
- /**
- * Private key of the coin.
- */
- struct TALER_CoinSpendPrivateKeyP coin_priv;
-
- /**
- * Amount this coin contributes to the melt, including fee.
- */
- struct TALER_Amount melt_amount_with_fee;
-
- /**
- * The applicable fee for melting a coin of this denomination
- */
- struct TALER_Amount fee_melt;
-
- /**
- * The original value of the coin.
- */
- struct TALER_Amount original_value;
-
- /**
- * Transfer private keys for each cut-and-choose dimension.
- */
- struct TALER_TransferPrivateKeyP transfer_priv[TALER_CNC_KAPPA];
-
- /**
- * Timestamp indicating when coins of this denomination become invalid.
- */
- struct GNUNET_TIME_Absolute expire_deposit;
-
- /**
- * Denomination key of the original coin.
- */
- struct TALER_DenominationPublicKey pub_key;
-
- /**
- * Exchange's signature over the coin.
- */
- struct TALER_DenominationSignature sig;
-
-};
-
-
-/**
- * Melt data in non-serialized format for convenient processing.
- */
-struct MeltData
-{
-
- /**
- * Hash over the committed data during refresh operation.
- */
- struct TALER_RefreshCommitmentP rc;
-
- /**
- * Number of coins we are creating
- */
- uint16_t num_fresh_coins;
-
- /**
- * Information about the melted coin.
- */
- struct MeltedCoin melted_coin;
-
- /**
- * Array of @e num_fresh_coins denomination keys for the coins to be
- * freshly exchangeed.
- */
- struct TALER_DenominationPublicKey *fresh_pks;
-
- /**
- * Arrays of @e num_fresh_coins with information about the fresh
- * coins to be created, for each cut-and-choose dimension.
- */
- struct TALER_PlanchetSecretsP *fresh_coins[TALER_CNC_KAPPA];
-};
-
-
-/**
- * Free all information associated with a melted coin session.
- *
- * @param mc melted coin to release, the pointer itself is NOT
- * freed (as it is typically not allocated by itself)
- */
-static void
-free_melted_coin (struct MeltedCoin *mc)
-{
- if (NULL != mc->pub_key.rsa_public_key)
- GNUNET_CRYPTO_rsa_public_key_free (mc->pub_key.rsa_public_key);
- if (NULL != mc->sig.rsa_signature)
- GNUNET_CRYPTO_rsa_signature_free (mc->sig.rsa_signature);
-}
-
-
-/**
- * Free all information associated with a melting session. Note
- * that we allow the melting session to be only partially initialized,
- * as we use this function also when freeing melt data that was not
- * fully initialized (i.e. due to failures in #deserialize_melt_data()).
- *
- * @param md melting data to release, the pointer itself is NOT
- * freed (as it is typically not allocated by itself)
- */
-static void
-free_melt_data (struct MeltData *md)
-{
- free_melted_coin (&md->melted_coin);
- if (NULL != md->fresh_pks)
- {
- for (unsigned int i = 0; i<md->num_fresh_coins; i++)
- if (NULL != md->fresh_pks[i].rsa_public_key)
- GNUNET_CRYPTO_rsa_public_key_free (md->fresh_pks[i].rsa_public_key);
- GNUNET_free (md->fresh_pks);
- }
-
- for (unsigned int i = 0; i<TALER_CNC_KAPPA; i++)
- GNUNET_free_non_null (md->fresh_coins[i]);
- /* Finally, clean up a bit...
- (NOTE: compilers might optimize this away, so this is
- not providing any strong assurances that the key material
- is purged.) */
- memset (md,
- 0,
- sizeof (struct MeltData));
-}
-
-
-/**
- * Serialize information about a coin we are melting.
- *
- * @param mc information to serialize
- * @param buf buffer to write data in, NULL to just compute
- * required size
- * @param off offeset at @a buf to use
- * @return number of bytes written to @a buf at @a off, or if
- * @a buf is NULL, number of bytes required; 0 on error
- */
-static size_t
-serialize_melted_coin (const struct MeltedCoin *mc,
- char *buf,
- size_t off)
-{
- struct MeltedCoinP mcp;
- unsigned int i;
- char *pbuf;
- size_t pbuf_size;
- char *sbuf;
- size_t sbuf_size;
-
- sbuf_size = GNUNET_CRYPTO_rsa_signature_encode (mc->sig.rsa_signature,
- &sbuf);
- pbuf_size = GNUNET_CRYPTO_rsa_public_key_encode (mc->pub_key.rsa_public_key,
- &pbuf);
- if (NULL == buf)
- {
- GNUNET_free (sbuf);
- GNUNET_free (pbuf);
- return sizeof (struct MeltedCoinP) + sbuf_size + pbuf_size;
- }
- if ( (sbuf_size > UINT16_MAX) ||
- (pbuf_size > UINT16_MAX) )
- {
- GNUNET_break (0);
- return 0;
- }
- mcp.coin_priv = mc->coin_priv;
- TALER_amount_hton (&mcp.melt_amount_with_fee,
- &mc->melt_amount_with_fee);
- TALER_amount_hton (&mcp.fee_melt,
- &mc->fee_melt);
- TALER_amount_hton (&mcp.original_value,
- &mc->original_value);
- for (i = 0; i<TALER_CNC_KAPPA; i++)
- mcp.transfer_priv[i] = mc->transfer_priv[i];
- mcp.expire_deposit = GNUNET_TIME_absolute_hton (mc->expire_deposit);
- mcp.pbuf_size = htons ((uint16_t) pbuf_size);
- mcp.sbuf_size = htons ((uint16_t) sbuf_size);
- memcpy (&buf[off],
- &mcp,
- sizeof (struct MeltedCoinP));
- memcpy (&buf[off + sizeof (struct MeltedCoinP)],
- pbuf,
- pbuf_size);
- memcpy (&buf[off + sizeof (struct MeltedCoinP) + pbuf_size],
- sbuf,
- sbuf_size);
- GNUNET_free (sbuf);
- GNUNET_free (pbuf);
- return sizeof (struct MeltedCoinP) + sbuf_size + pbuf_size;
-}
-
-
-/**
- * Deserialize information about a coin we are melting.
- *
- * @param[out] mc information to deserialize
- * @param buf buffer to read data from
- * @param size number of bytes available at @a buf to use
- * @param[out] ok set to #GNUNET_NO to report errors
- * @return number of bytes read from @a buf, 0 on error
- */
-static size_t
-deserialize_melted_coin (struct MeltedCoin *mc,
- const char *buf,
- size_t size,
- int *ok)
-{
- struct MeltedCoinP mcp;
- unsigned int i;
- size_t pbuf_size;
- size_t sbuf_size;
- size_t off;
-
- if (size < sizeof (struct MeltedCoinP))
- {
- GNUNET_break (0);
- *ok = GNUNET_NO;
- return 0;
- }
- memcpy (&mcp,
- buf,
- sizeof (struct MeltedCoinP));
- pbuf_size = ntohs (mcp.pbuf_size);
- sbuf_size = ntohs (mcp.sbuf_size);
- if (size < sizeof (struct MeltedCoinP) + pbuf_size + sbuf_size)
- {
- GNUNET_break (0);
- *ok = GNUNET_NO;
- return 0;
- }
- off = sizeof (struct MeltedCoinP);
- mc->pub_key.rsa_public_key
- = GNUNET_CRYPTO_rsa_public_key_decode (&buf[off],
- pbuf_size);
- off += pbuf_size;
- mc->sig.rsa_signature
- = GNUNET_CRYPTO_rsa_signature_decode (&buf[off],
- sbuf_size);
- off += sbuf_size;
- if ( (NULL == mc->pub_key.rsa_public_key) ||
- (NULL == mc->sig.rsa_signature) )
- {
- GNUNET_break (0);
- *ok = GNUNET_NO;
- return 0;
- }
-
- mc->coin_priv = mcp.coin_priv;
- TALER_amount_ntoh (&mc->melt_amount_with_fee,
- &mcp.melt_amount_with_fee);
- TALER_amount_ntoh (&mc->fee_melt,
- &mcp.fee_melt);
- TALER_amount_ntoh (&mc->original_value,
- &mcp.original_value);
- for (i = 0; i<TALER_CNC_KAPPA; i++)
- mc->transfer_priv[i] = mcp.transfer_priv[i];
- mc->expire_deposit = GNUNET_TIME_absolute_ntoh (mcp.expire_deposit);
- return off;
-}
-
-
-/**
- * Serialize information about a denomination key.
- *
- * @param dk information to serialize
- * @param buf buffer to write data in, NULL to just compute
- * required size
- * @param off offeset at @a buf to use
- * @return number of bytes written to @a buf at @a off, or if
- * @a buf is NULL, number of bytes required
- */
-static size_t
-serialize_denomination_key (const struct TALER_DenominationPublicKey *dk,
- char *buf,
- size_t off)
-{
- char *pbuf;
- size_t pbuf_size;
- uint32_t be;
-
- pbuf_size = GNUNET_CRYPTO_rsa_public_key_encode (dk->rsa_public_key,
- &pbuf);
- if (NULL == buf)
- {
- GNUNET_free (pbuf);
- return pbuf_size + sizeof (uint32_t);
- }
- be = htonl ((uint32_t) pbuf_size);
- memcpy (&buf[off],
- &be,
- sizeof (uint32_t));
- memcpy (&buf[off + sizeof (uint32_t)],
- pbuf,
- pbuf_size);
- GNUNET_free (pbuf);
- return pbuf_size + sizeof (uint32_t);
-}
-
-
-/**
- * Deserialize information about a denomination key.
- *
- * @param[out] dk information to deserialize
- * @param buf buffer to read data from
- * @param size number of bytes available at @a buf to use
- * @param[out] ok set to #GNUNET_NO to report errors
- * @return number of bytes read from @a buf, 0 on error
- */
-static size_t
-deserialize_denomination_key (struct TALER_DenominationPublicKey *dk,
- const char *buf,
- size_t size,
- int *ok)
-{
- size_t pbuf_size;
- uint32_t be;
-
- if (size < sizeof (uint32_t))
- {
- GNUNET_break (0);
- *ok = GNUNET_NO;
- return 0;
- }
- memcpy (&be,
- buf,
- sizeof (uint32_t));
- pbuf_size = ntohl (be);
- if (size < sizeof (uint32_t) + pbuf_size)
- {
- GNUNET_break (0);
- *ok = GNUNET_NO;
- return 0;
- }
- dk->rsa_public_key
- = GNUNET_CRYPTO_rsa_public_key_decode (&buf[sizeof (uint32_t)],
- pbuf_size);
- if (NULL == dk->rsa_public_key)
- {
- GNUNET_break (0);
- *ok = GNUNET_NO;
- return 0;
- }
- return sizeof (uint32_t) + pbuf_size;
-}
-
-
-/**
- * Serialize information about a fresh coin we are generating.
- *
- * @param fc information to serialize
- * @param buf buffer to write data in, NULL to just compute
- * required size
- * @param off offeset at @a buf to use
- * @return number of bytes written to @a buf at @a off, or if
- * @a buf is NULL, number of bytes required
- */
-static size_t
-serialize_fresh_coin (const struct TALER_PlanchetSecretsP *fc,
- char *buf,
- size_t off)
-{
- if (NULL != buf)
- memcpy (&buf[off],
- fc,
- sizeof (struct TALER_PlanchetSecretsP));
- return sizeof (struct TALER_PlanchetSecretsP);
-}
-
-
-/**
- * Deserialize information about a fresh coin we are generating.
- *
- * @param[out] fc information to deserialize
- * @param buf buffer to read data from
- * @param size number of bytes available at @a buf to use
- * @param[out] ok set to #GNUNET_NO to report errors
- * @return number of bytes read from @a buf, 0 on error
- */
-static size_t
-deserialize_fresh_coin (struct TALER_PlanchetSecretsP *fc,
- const char *buf,
- size_t size,
- int *ok)
-{
- if (size < sizeof (struct TALER_PlanchetSecretsP))
- {
- GNUNET_break (0);
- *ok = GNUNET_NO;
- return 0;
- }
- memcpy (fc,
- buf,
- sizeof (struct TALER_PlanchetSecretsP));
- return sizeof (struct TALER_PlanchetSecretsP);
-}
-
-
-/**
- * Serialize melt data.
- *
- * @param md data to serialize
- * @param[out] res_size size of buffer returned
- * @return serialized melt data
- */
-static char *
-serialize_melt_data (const struct MeltData *md,
- size_t *res_size)
-{
- size_t size;
- size_t asize;
- char *buf;
-
- size = 0;
- asize = (size_t) -1; /* make the compiler happy */
- buf = NULL;
- /* we do 2 iterations, #1 to determine total size, #2 to
- actually construct the buffer */
- do {
- if (0 == size)
- {
- size = sizeof (struct MeltDataP);
- }
- else
- {
- struct MeltDataP *mdp;
-
- buf = GNUNET_malloc (size);
- asize = size; /* just for invariant check later */
- size = sizeof (struct MeltDataP);
- mdp = (struct MeltDataP *) buf;
- mdp->rc = md->rc;
- mdp->num_fresh_coins = htons (md->num_fresh_coins);
- }
- size += serialize_melted_coin (&md->melted_coin,
- buf,
- size);
- for (unsigned int i = 0; i<md->num_fresh_coins; i++)
- size += serialize_denomination_key (&md->fresh_pks[i],
- buf,
- size);
- for (unsigned int i = 0; i<TALER_CNC_KAPPA; i++)
- for (unsigned int j = 0; j<md->num_fresh_coins; j++)
- size += serialize_fresh_coin (&md->fresh_coins[i][j],
- buf,
- size);
- } while (NULL == buf);
- GNUNET_assert (size == asize);
- *res_size = size;
- return buf;
-}
-
-
-/**
- * Deserialize melt data.
- *
- * @param buf serialized data
- * @param buf_size size of @a buf
- * @return deserialized melt data, NULL on error
- */
-static struct MeltData *
-deserialize_melt_data (const char *buf,
- size_t buf_size)
-{
- struct MeltData *md;
- struct MeltDataP mdp;
- size_t off;
- int ok;
-
- if (buf_size < sizeof (struct MeltDataP))
- return NULL;
- memcpy (&mdp,
- buf,
- sizeof (struct MeltDataP));
- md = GNUNET_new (struct MeltData);
- md->rc = mdp.rc;
- md->num_fresh_coins = ntohs (mdp.num_fresh_coins);
- md->fresh_pks = GNUNET_new_array (md->num_fresh_coins,
- struct TALER_DenominationPublicKey);
- for (unsigned int i = 0; i<TALER_CNC_KAPPA; i++)
- md->fresh_coins[i] = GNUNET_new_array (md->num_fresh_coins,
- struct TALER_PlanchetSecretsP);
- off = sizeof (struct MeltDataP);
- ok = GNUNET_YES;
- off += deserialize_melted_coin (&md->melted_coin,
- &buf[off],
- buf_size - off,
- &ok);
- for (unsigned int i = 0; (i<md->num_fresh_coins) && (GNUNET_YES == ok); i++)
- off += deserialize_denomination_key (&md->fresh_pks[i],
- &buf[off],
- buf_size - off,
- &ok);
-
- for (unsigned int i = 0; i<TALER_CNC_KAPPA; i++)
- for (unsigned int j = 0; (j<md->num_fresh_coins) && (GNUNET_YES == ok); j++)
- off += deserialize_fresh_coin (&md->fresh_coins[i][j],
- &buf[off],
- buf_size - off,
- &ok);
- if (off != buf_size)
- {
- GNUNET_break (0);
- ok = GNUNET_NO;
- }
- if (GNUNET_YES != ok)
- {
- free_melt_data (md);
- GNUNET_free (md);
- return NULL;
- }
- return md;
-}
-
-
-/**
- * Melt (partially spent) coins to obtain fresh coins that are
- * unlinkable to the original coin(s). Note that melting more
- * than one coin in a single request will make those coins linkable,
- * so the safest operation only melts one coin at a time.
- *
- * This API is typically used by a wallet. Note that to ensure that
- * no money is lost in case of hardware failures, this operation does
- * not actually initiate the request. Instead, it generates a buffer
- * which the caller must store before proceeding with the actual call
- * to #TALER_EXCHANGE_refresh_melt() that will generate the request.
- *
- * This function does verify that the given request data is internally
- * consistent. However, the @a melts_sigs are NOT verified.
- *
- * Aside from some non-trivial cryptographic operations that might
- * take a bit of CPU time to complete, this function returns
- * its result immediately and does not start any asynchronous
- * processing. This function is also thread-safe.
- *
- * @param melt_priv private key of the coin to melt
- * @param melt_amount amount specifying how much
- * the coin will contribute to the melt (including fee)
- * @param melt_sig signature affirming the
- * validity of the public keys corresponding to the
- * @a melt_priv private key
- * @param melt_pk denomination key information
- * record corresponding to the @a melt_sig
- * validity of the keys
- * @param fresh_pks_len length of the @a pks array
- * @param fresh_pks array of @a pks_len denominations of fresh coins to create
- * @param[out] res_size set to the size of the return value, or 0 on error
- * @return NULL
- * if the inputs are invalid (i.e. denomination key not with this exchange).
- * Otherwise, pointer to a buffer of @a res_size to store persistently
- * before proceeding to #TALER_EXCHANGE_refresh_melt().
- * Non-null results should be freed using GNUNET_free().
- */
-char *
-TALER_EXCHANGE_refresh_prepare (const struct
- TALER_CoinSpendPrivateKeyP *melt_priv,
- const struct TALER_Amount *melt_amount,
- const struct
- TALER_DenominationSignature *melt_sig,
- const struct
- TALER_EXCHANGE_DenomPublicKey *melt_pk,
- unsigned int fresh_pks_len,
- const struct
- TALER_EXCHANGE_DenomPublicKey *fresh_pks,
- size_t *res_size)
-{
- struct MeltData md;
- char *buf;
- struct TALER_Amount total;
- struct TALER_CoinSpendPublicKeyP coin_pub;
- struct TALER_TransferSecretP trans_sec[TALER_CNC_KAPPA];
- struct TALER_RefreshCommitmentEntry rce[TALER_CNC_KAPPA];
-
- GNUNET_CRYPTO_eddsa_key_get_public (&melt_priv->eddsa_priv,
- &coin_pub.eddsa_pub);
- /* build up melt data structure */
- memset (&md, 0, sizeof (md));
- md.num_fresh_coins = fresh_pks_len;
- md.melted_coin.coin_priv = *melt_priv;
- md.melted_coin.melt_amount_with_fee = *melt_amount;
- md.melted_coin.fee_melt = melt_pk->fee_refresh;
- md.melted_coin.original_value = melt_pk->value;
- md.melted_coin.expire_deposit
- = melt_pk->expire_deposit;
- GNUNET_assert (GNUNET_OK ==
- TALER_amount_get_zero (melt_amount->currency,
- &total));
- md.melted_coin.pub_key.rsa_public_key
- = GNUNET_CRYPTO_rsa_public_key_dup (melt_pk->key.rsa_public_key);
- md.melted_coin.sig.rsa_signature
- = GNUNET_CRYPTO_rsa_signature_dup (melt_sig->rsa_signature);
- md.fresh_pks = GNUNET_new_array (fresh_pks_len,
- struct TALER_DenominationPublicKey);
- for (unsigned int i = 0; i<fresh_pks_len; i++)
- {
- md.fresh_pks[i].rsa_public_key
- = GNUNET_CRYPTO_rsa_public_key_dup (fresh_pks[i].key.rsa_public_key);
- if ( (GNUNET_OK !=
- TALER_amount_add (&total,
- &total,
- &fresh_pks[i].value)) ||
- (GNUNET_OK !=
- TALER_amount_add (&total,
- &total,
- &fresh_pks[i].fee_withdraw)) )
- {
- GNUNET_break (0);
- free_melt_data (&md);
- return NULL;
- }
- }
- /* verify that melt_amount is above total cost */
- if (1 ==
- TALER_amount_cmp (&total,
- melt_amount) )
- {
- /* Eh, this operation is more expensive than the
- @a melt_amount. This is not OK. */
- GNUNET_break (0);
- free_melt_data (&md);
- return NULL;
- }
-
- /* build up coins */
- for (unsigned int i = 0; i<TALER_CNC_KAPPA; i++)
- {
- struct GNUNET_CRYPTO_EcdhePrivateKey *tpk;
-
- tpk = GNUNET_CRYPTO_ecdhe_key_create ();
- md.melted_coin.transfer_priv[i].ecdhe_priv = *tpk;
- GNUNET_free (tpk);
-
- GNUNET_CRYPTO_ecdhe_key_get_public (
- &md.melted_coin.transfer_priv[i].ecdhe_priv,
- &rce[i].transfer_pub.ecdhe_pub);
- TALER_link_derive_transfer_secret (melt_priv,
- &md.melted_coin.transfer_priv[i],
- &trans_sec[i]);
- md.fresh_coins[i] = GNUNET_new_array (fresh_pks_len,
- struct TALER_PlanchetSecretsP);
- rce[i].new_coins = GNUNET_new_array (fresh_pks_len,
- struct TALER_RefreshCoinData);
- for (unsigned int j = 0; j<fresh_pks_len; j++)
- {
- struct TALER_PlanchetSecretsP *fc = &md.fresh_coins[i][j];
- struct TALER_RefreshCoinData *rcd = &rce[i].new_coins[j];
- struct TALER_PlanchetDetail pd;
-
- TALER_planchet_setup_refresh (&trans_sec[i],
- j,
- fc);
- if (GNUNET_OK !=
- TALER_planchet_prepare (&md.fresh_pks[j],
- fc,
- &pd))
- {
- GNUNET_break_op (0);
- free_melt_data (&md);
- return NULL;
- }
- rcd->dk = &md.fresh_pks[j];
- rcd->coin_ev = pd.coin_ev;
- rcd->coin_ev_size = pd.coin_ev_size;
- }
- }
-
- /* Compute refresh commitment */
- TALER_refresh_get_commitment (&md.rc,
- TALER_CNC_KAPPA,
- fresh_pks_len,
- rce,
- &coin_pub,
- melt_amount);
- /* finally, serialize everything */
- buf = serialize_melt_data (&md,
- res_size);
- for (unsigned int i = 0; i < TALER_CNC_KAPPA; i++)
- {
- for (unsigned int j = 0; j < fresh_pks_len; j++)
- GNUNET_free_non_null (rce[i].new_coins[j].coin_ev);
- GNUNET_free_non_null (rce[i].new_coins);
- }
- free_melt_data (&md);
- return buf;
-}
-
-
-/* ********************* /refresh/melt ***************************** */
-
-
-/**
- * @brief A /refresh/melt Handle
- */
-struct TALER_EXCHANGE_RefreshMeltHandle
-{
-
- /**
- * The connection to exchange this request handle will use
- */
- struct TALER_EXCHANGE_Handle *exchange;
-
- /**
- * The url for this request.
- */
- char *url;
-
- /**
- * Context for #TEH_curl_easy_post(). Keeps the data that must
- * persist for Curl to make the upload.
- */
- struct TALER_CURL_PostContext ctx;
-
- /**
- * Handle for the request.
- */
- struct GNUNET_CURL_Job *job;
-
- /**
- * Function to call with refresh melt failure results.
- */
- TALER_EXCHANGE_RefreshMeltCallback melt_cb;
-
- /**
- * Closure for @e result_cb and @e melt_failure_cb.
- */
- void *melt_cb_cls;
-
- /**
- * Actual information about the melt operation.
- */
- struct MeltData *md;
-
- /**
- * @brief Public information about the coin's denomination key
- */
- struct TALER_EXCHANGE_DenomPublicKey dki;
-};
-
-
-/**
- * Verify that the signature on the "200 OK" response
- * from the exchange is valid.
- *
- * @param rmh melt handle
- * @param json json reply with the signature
- * @param[out] exchange_pub public key of the exchange used for the signature
- * @param[out] noreveal_index set to the noreveal index selected by the exchange
- * @return #GNUNET_OK if the signature is valid, #GNUNET_SYSERR if not
- */
-static int
-verify_refresh_melt_signature_ok (struct TALER_EXCHANGE_RefreshMeltHandle *rmh,
- const json_t *json,
- struct TALER_ExchangePublicKeyP *exchange_pub,
- uint32_t *noreveal_index)
-{
- struct TALER_ExchangeSignatureP exchange_sig;
- const struct TALER_EXCHANGE_Keys *key_state;
- struct GNUNET_JSON_Specification spec[] = {
- GNUNET_JSON_spec_fixed_auto ("exchange_sig", &exchange_sig),
- GNUNET_JSON_spec_fixed_auto ("exchange_pub", exchange_pub),
- GNUNET_JSON_spec_uint32 ("noreveal_index", noreveal_index),
- GNUNET_JSON_spec_end ()
- };
- struct TALER_RefreshMeltConfirmationPS confirm;
-
- if (GNUNET_OK !=
- GNUNET_JSON_parse (json,
- spec,
- NULL, NULL))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
-
- /* check that exchange signing key is permitted */
- key_state = TALER_EXCHANGE_get_keys (rmh->exchange);
- if (GNUNET_OK !=
- TALER_EXCHANGE_test_signing_key (key_state,
- exchange_pub))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
-
- /* check that noreveal index is in permitted range */
- if (TALER_CNC_KAPPA <= *noreveal_index)
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
-
- /* verify signature by exchange */
- confirm.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_MELT);
- confirm.purpose.size = htonl (sizeof (struct
- TALER_RefreshMeltConfirmationPS));
- confirm.rc = rmh->md->rc;
- confirm.noreveal_index = htonl (*noreveal_index);
- if (GNUNET_OK !=
- GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_EXCHANGE_CONFIRM_MELT,
- &confirm.purpose,
- &exchange_sig.eddsa_signature,
- &exchange_pub->eddsa_pub))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- return GNUNET_OK;
-}
-
-
-/**
- * Verify that the signatures on the "409 CONFLICT" response from the
- * exchange demonstrating customer double-spending are valid.
- *
- * @param rmh melt handle
- * @param json json reply with the signature(s) and transaction history
- * @return #GNUNET_OK if the signature(s) is valid, #GNUNET_SYSERR if not
- */
-static int
-verify_refresh_melt_signature_conflict (struct
- TALER_EXCHANGE_RefreshMeltHandle *rmh,
- const json_t *json)
-{
- json_t *history;
- struct TALER_Amount original_value;
- struct TALER_Amount melt_value_with_fee;
- struct TALER_Amount total;
- struct TALER_CoinSpendPublicKeyP coin_pub;
- struct GNUNET_JSON_Specification spec[] = {
- GNUNET_JSON_spec_json ("history", &history),
- GNUNET_JSON_spec_fixed_auto ("coin_pub", &coin_pub),
- TALER_JSON_spec_amount ("original_value", &original_value),
- TALER_JSON_spec_amount ("requested_value", &melt_value_with_fee),
- GNUNET_JSON_spec_end ()
- };
- const struct MeltedCoin *mc;
-
- /* parse JSON reply */
- if (GNUNET_OK !=
- GNUNET_JSON_parse (json,
- spec,
- NULL, NULL))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
-
- /* Find out which coin was deemed problematic by the exchange */
- mc = &rmh->md->melted_coin;
-
- /* check basic coin properties */
- if (0 != TALER_amount_cmp (&original_value,
- &mc->original_value))
- {
- /* We disagree on the value of the coin */
- GNUNET_break_op (0);
- json_decref (history);
- return GNUNET_SYSERR;
- }
- if (0 != TALER_amount_cmp (&melt_value_with_fee,
- &mc->melt_amount_with_fee))
- {
- /* We disagree on the value of the coin */
- GNUNET_break_op (0);
- json_decref (history);
- return GNUNET_SYSERR;
- }
-
- /* verify coin history */
- history = json_object_get (json,
- "history");
- if (GNUNET_OK !=
- TALER_EXCHANGE_verify_coin_history (&rmh->dki,
- original_value.currency,
- &coin_pub,
- history,
- &total))
- {
- GNUNET_break_op (0);
- json_decref (history);
- return GNUNET_SYSERR;
- }
- json_decref (history);
-
- /* check if melt operation was really too expensive given history */
- if (GNUNET_OK !=
- TALER_amount_add (&total,
- &total,
- &melt_value_with_fee))
- {
- /* clearly not OK if our transaction would have caused
- the overflow... */
- return GNUNET_OK;
- }
-
- if (0 >= TALER_amount_cmp (&total,
- &original_value))
- {
- /* transaction should have still fit */
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
-
- /* everything OK, valid proof of double-spending was provided */
- return GNUNET_OK;
-}
-
-
-/**
- * Function called when we're done processing the
- * HTTP /refresh/melt request.
- *
- * @param cls the `struct TALER_EXCHANGE_RefreshMeltHandle`
- * @param response_code HTTP response code, 0 on error
- * @param response parsed JSON result, NULL on error
- */
-static void
-handle_refresh_melt_finished (void *cls,
- long response_code,
- const void *response)
-{
- struct TALER_EXCHANGE_RefreshMeltHandle *rmh = cls;
- uint32_t noreveal_index = TALER_CNC_KAPPA; /* invalid value */
- struct TALER_ExchangePublicKeyP exchange_pub;
- const json_t *j = response;
-
- rmh->job = NULL;
- switch (response_code)
- {
- case 0:
- break;
- case MHD_HTTP_OK:
- if (GNUNET_OK !=
- verify_refresh_melt_signature_ok (rmh,
- j,
- &exchange_pub,
- &noreveal_index))
- {
- GNUNET_break_op (0);
- response_code = 0;
- }
- if (NULL != rmh->melt_cb)
- {
- rmh->melt_cb (rmh->melt_cb_cls,
- response_code,
- TALER_JSON_get_error_code (j),
- noreveal_index,
- (0 == response_code) ? NULL : &exchange_pub,
- j);
- rmh->melt_cb = NULL;
- }
- break;
- case MHD_HTTP_BAD_REQUEST:
- /* This should never happen, either us or the exchange is buggy
- (or API version conflict); just pass JSON reply to the application */
- break;
- case MHD_HTTP_CONFLICT:
- /* Double spending; check signatures on transaction history */
- if (GNUNET_OK !=
- verify_refresh_melt_signature_conflict (rmh,
- j))
- {
- GNUNET_break_op (0);
- response_code = 0;
- }
- break;
- case MHD_HTTP_FORBIDDEN:
- /* Nothing really to verify, exchange says one of the signatures is
- invalid; assuming we checked them, this should never happen, we
- should pass the JSON reply to the application */
- break;
- case MHD_HTTP_NOT_FOUND:
- /* Nothing really to verify, this should never
- happen, we should pass the JSON reply to the application */
- break;
- case MHD_HTTP_INTERNAL_SERVER_ERROR:
- /* Server had an internal issue; we should retry, but this API
- leaves this to the application */
- break;
- default:
- /* unexpected response code */
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Unexpected response code %u\n",
- (unsigned int) response_code);
- GNUNET_break (0);
- response_code = 0;
- break;
- }
- if (NULL != rmh->melt_cb)
- rmh->melt_cb (rmh->melt_cb_cls,
- response_code,
- TALER_JSON_get_error_code (j),
- UINT32_MAX,
- NULL,
- j);
- TALER_EXCHANGE_refresh_melt_cancel (rmh);
-}
-
-
-/**
- * Submit a melt request to the exchange and get the exchange's
- * response.
- *
- * This API is typically used by a wallet. Note that to ensure that
- * no money is lost in case of hardware failures, the provided
- * argument should have been constructed using
- * #TALER_EXCHANGE_refresh_prepare and committed to persistent storage
- * prior to calling this function.
- *
- * @param exchange the exchange handle; the exchange must be ready to operate
- * @param refresh_data_length size of the @a refresh_data (returned
- * in the `res_size` argument from #TALER_EXCHANGE_refresh_prepare())
- * @param refresh_data the refresh data as returned from
- #TALER_EXCHANGE_refresh_prepare())
- * @param melt_cb the callback to call with the result
- * @param melt_cb_cls closure for @a melt_cb
- * @return a handle for this request; NULL if the argument was invalid.
- * In this case, neither callback will be called.
- */
-struct TALER_EXCHANGE_RefreshMeltHandle *
-TALER_EXCHANGE_refresh_melt (struct TALER_EXCHANGE_Handle *exchange,
- size_t refresh_data_length,
- const char *refresh_data,
- TALER_EXCHANGE_RefreshMeltCallback melt_cb,
- void *melt_cb_cls)
-{
- const struct TALER_EXCHANGE_Keys *key_state;
- const struct TALER_EXCHANGE_DenomPublicKey *dki;
- json_t *melt_obj;
- struct TALER_EXCHANGE_RefreshMeltHandle *rmh;
- CURL *eh;
- struct GNUNET_CURL_Context *ctx;
- struct MeltData *md;
- struct TALER_CoinSpendSignatureP confirm_sig;
- struct TALER_RefreshMeltCoinAffirmationPS melt;
- struct GNUNET_HashCode h_denom_pub;
- char arg_str[sizeof (struct TALER_CoinSpendPublicKeyP) * 2 + 32];
-
- GNUNET_assert (GNUNET_YES ==
- TEAH_handle_is_ready (exchange));
- md = deserialize_melt_data (refresh_data,
- refresh_data_length);
- if (NULL == md)
- {
- GNUNET_break (0);
- return NULL;
- }
- melt.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_MELT);
- melt.purpose.size = htonl (sizeof (struct
- TALER_RefreshMeltCoinAffirmationPS));
- melt.rc = md->rc;
- TALER_amount_hton (&melt.amount_with_fee,
- &md->melted_coin.melt_amount_with_fee);
- TALER_amount_hton (&melt.melt_fee,
- &md->melted_coin.fee_melt);
- GNUNET_CRYPTO_eddsa_key_get_public (&md->melted_coin.coin_priv.eddsa_priv,
- &melt.coin_pub.eddsa_pub);
- GNUNET_CRYPTO_eddsa_sign (&md->melted_coin.coin_priv.eddsa_priv,
- &melt.purpose,
- &confirm_sig.eddsa_signature);
- GNUNET_CRYPTO_rsa_public_key_hash (md->melted_coin.pub_key.rsa_public_key,
- &h_denom_pub);
- melt_obj = json_pack ("{s:o, s:o, s:o, s:o, s:o, s:o}",
- "coin_pub",
- GNUNET_JSON_from_data_auto (&melt.coin_pub),
- "denom_pub_hash",
- GNUNET_JSON_from_data_auto (&h_denom_pub),
- "denom_sig",
- GNUNET_JSON_from_rsa_signature (
- md->melted_coin.sig.rsa_signature),
- "confirm_sig",
- GNUNET_JSON_from_data_auto (&confirm_sig),
- "value_with_fee",
- TALER_JSON_from_amount (
- &md->melted_coin.melt_amount_with_fee),
- "rc",
- GNUNET_JSON_from_data_auto (&melt.rc));
- if (NULL == melt_obj)
- {
- GNUNET_break (0);
- free_melt_data (md);
- return NULL;
- }
- {
- char pub_str[sizeof (struct TALER_CoinSpendPublicKeyP) * 2];
- char *end;
-
- end = GNUNET_STRINGS_data_to_string (&melt.coin_pub,
- sizeof (struct
- TALER_CoinSpendPublicKeyP),
- pub_str,
- sizeof (pub_str));
- *end = '\0';
- GNUNET_snprintf (arg_str,
- sizeof (arg_str),
- "/coins/%s/melt",
- pub_str);
- }
-
- key_state = TALER_EXCHANGE_get_keys (exchange);
- dki = TALER_EXCHANGE_get_denomination_key (key_state,
- &md->melted_coin.pub_key);
-
- /* and now we can at last begin the actual request handling */
- rmh = GNUNET_new (struct TALER_EXCHANGE_RefreshMeltHandle);
- rmh->exchange = exchange;
- rmh->dki = *dki;
- rmh->dki.key.rsa_public_key = NULL; /* lifetime not warranted, so better
- not copy the pointer */
- rmh->melt_cb = melt_cb;
- rmh->melt_cb_cls = melt_cb_cls;
- rmh->md = md;
- rmh->url = TEAH_path_to_url (exchange,
- arg_str);
- eh = TEL_curl_easy_get (rmh->url);
- if (GNUNET_OK !=
- TALER_curl_easy_post (&rmh->ctx,
- eh,
- melt_obj))
- {
- GNUNET_break (0);
- curl_easy_cleanup (eh);
- json_decref (melt_obj);
- GNUNET_free (rmh->url);
- GNUNET_free (rmh);
- return NULL;
- }
- json_decref (melt_obj);
- ctx = TEAH_handle_to_context (exchange);
- rmh->job = GNUNET_CURL_job_add2 (ctx,
- eh,
- rmh->ctx.headers,
- &handle_refresh_melt_finished,
- rmh);
- return rmh;
-}
-
-
-/**
- * Cancel a refresh execute request. This function cannot be used
- * on a request handle if either callback was already invoked.
- *
- * @param rmh the refresh melt handle
- */
-void
-TALER_EXCHANGE_refresh_melt_cancel (struct
- TALER_EXCHANGE_RefreshMeltHandle *rmh)
-{
- if (NULL != rmh->job)
- {
- GNUNET_CURL_job_cancel (rmh->job);
- rmh->job = NULL;
- }
- free_melt_data (rmh->md); /* does not free 'md' itself */
- GNUNET_free (rmh->md);
- GNUNET_free (rmh->url);
- TALER_curl_easy_post_finished (&rmh->ctx);
- GNUNET_free (rmh);
-}
-
-
-/* ********************* /refreshes/$RCH/reveal ***************************** */
-
-
-/**
- * @brief A /refreshes/$RCH/reveal Handle
- */
-struct TALER_EXCHANGE_RefreshRevealHandle
-{
-
- /**
- * The connection to exchange this request handle will use
- */
- struct TALER_EXCHANGE_Handle *exchange;
-
- /**
- * The url for this request.
- */
- char *url;
-
- /**
- * Context for #TEH_curl_easy_post(). Keeps the data that must
- * persist for Curl to make the upload.
- */
- struct TALER_CURL_PostContext ctx;
-
- /**
- * Handle for the request.
- */
- struct GNUNET_CURL_Job *job;
-
- /**
- * Function to call with the result.
- */
- TALER_EXCHANGE_RefreshRevealCallback reveal_cb;
-
- /**
- * Closure for @e reveal_cb.
- */
- void *reveal_cb_cls;
-
- /**
- * Actual information about the melt operation.
- */
- struct MeltData *md;
-
- /**
- * The index selected by the exchange in cut-and-choose to not be revealed.
- */
- uint16_t noreveal_index;
-
-};
-
-
-/**
- * We got a 200 OK response for the /refreshes/$RCH/reveal operation.
- * Extract the coin signatures and return them to the caller.
- * The signatures we get from the exchange is for the blinded value.
- * Thus, we first must unblind them and then should verify their
- * validity.
- *
- * If everything checks out, we return the unblinded signatures
- * to the application via the callback.
- *
- * @param rrh operation handle
- * @param json reply from the exchange
- * @param[out] sigs array of length `num_fresh_coins`, initialized to cointain RSA signatures
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on errors
- */
-static int
-refresh_reveal_ok (struct TALER_EXCHANGE_RefreshRevealHandle *rrh,
- const json_t *json,
- struct TALER_DenominationSignature *sigs)
-{
- json_t *jsona;
- struct GNUNET_JSON_Specification outer_spec[] = {
- GNUNET_JSON_spec_json ("ev_sigs", &jsona),
- GNUNET_JSON_spec_end ()
- };
-
- if (GNUNET_OK !=
- GNUNET_JSON_parse (json,
- outer_spec,
- NULL, NULL))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- if (! json_is_array (jsona))
- {
- /* We expected an array of coins */
- GNUNET_break_op (0);
- GNUNET_JSON_parse_free (outer_spec);
- return GNUNET_SYSERR;
- }
- if (rrh->md->num_fresh_coins != json_array_size (jsona))
- {
- /* Number of coins generated does not match our expectation */
- GNUNET_break_op (0);
- GNUNET_JSON_parse_free (outer_spec);
- return GNUNET_SYSERR;
- }
- for (unsigned int i = 0; i<rrh->md->num_fresh_coins; i++)
- {
- const struct TALER_PlanchetSecretsP *fc;
- struct TALER_DenominationPublicKey *pk;
- json_t *jsonai;
- struct GNUNET_CRYPTO_RsaSignature *blind_sig;
- struct TALER_CoinSpendPublicKeyP coin_pub;
- struct GNUNET_HashCode coin_hash;
- struct GNUNET_JSON_Specification spec[] = {
- GNUNET_JSON_spec_rsa_signature ("ev_sig", &blind_sig),
- GNUNET_JSON_spec_end ()
- };
- struct TALER_FreshCoin coin;
-
- fc = &rrh->md->fresh_coins[rrh->noreveal_index][i];
- pk = &rrh->md->fresh_pks[i];
- jsonai = json_array_get (jsona, i);
- GNUNET_assert (NULL != jsonai);
-
- if (GNUNET_OK !=
- GNUNET_JSON_parse (jsonai,
- spec,
- NULL, NULL))
- {
- GNUNET_break_op (0);
- GNUNET_JSON_parse_free (outer_spec);
- return GNUNET_SYSERR;
- }
-
- /* needed to verify the signature, and we didn't store it earlier,
- hence recomputing it here... */
- GNUNET_CRYPTO_eddsa_key_get_public (&fc->coin_priv.eddsa_priv,
- &coin_pub.eddsa_pub);
- GNUNET_CRYPTO_hash (&coin_pub.eddsa_pub,
- sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey),
- &coin_hash);
- if (GNUNET_OK !=
- TALER_planchet_to_coin (pk,
- blind_sig,
- fc,
- &coin_hash,
- &coin))
- {
- GNUNET_break_op (0);
- GNUNET_CRYPTO_rsa_signature_free (blind_sig);
- GNUNET_JSON_parse_free (outer_spec);
- return GNUNET_SYSERR;
- }
- GNUNET_CRYPTO_rsa_signature_free (blind_sig);
- sigs[i] = coin.sig;
- }
- GNUNET_JSON_parse_free (outer_spec);
- return GNUNET_OK;
-}
-
-
-/**
- * Function called when we're done processing the
- * HTTP /refreshes/$RCH/reveal request.
- *
- * @param cls the `struct TALER_EXCHANGE_RefreshHandle`
- * @param response_code HTTP response code, 0 on error
- * @param response parsed JSON result, NULL on error
- */
-static void
-handle_refresh_reveal_finished (void *cls,
- long response_code,
- const void *response)
-{
- struct TALER_EXCHANGE_RefreshRevealHandle *rrh = cls;
- const json_t *j = response;
-
- rrh->job = NULL;
- switch (response_code)
- {
- case 0:
- break;
- case MHD_HTTP_OK:
- {
- struct TALER_DenominationSignature sigs[rrh->md->num_fresh_coins];
- int ret;
-
- memset (sigs, 0, sizeof (sigs));
- ret = refresh_reveal_ok (rrh,
- j,
- sigs);
- if (GNUNET_OK != ret)
- {
- response_code = 0;
- }
- else
- {
- rrh->reveal_cb (rrh->reveal_cb_cls,
- MHD_HTTP_OK,
- TALER_EC_NONE,
- rrh->md->num_fresh_coins,
- rrh->md->fresh_coins[rrh->noreveal_index],
- sigs,
- j);
- rrh->reveal_cb = NULL;
- }
- for (unsigned int i = 0; i<rrh->md->num_fresh_coins; i++)
- if (NULL != sigs[i].rsa_signature)
- GNUNET_CRYPTO_rsa_signature_free (sigs[i].rsa_signature);
- }
- break;
- case MHD_HTTP_BAD_REQUEST:
- /* This should never happen, either us or the exchange is buggy
- (or API version conflict); just pass JSON reply to the application */
- break;
- case MHD_HTTP_CONFLICT:
- /* Nothing really to verify, exchange says our reveal is inconsitent
- with our commitment, so either side is buggy; we
- should pass the JSON reply to the application */
- break;
- case MHD_HTTP_INTERNAL_SERVER_ERROR:
- /* Server had an internal issue; we should retry, but this API
- leaves this to the application */
- break;
- default:
- /* unexpected response code */
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Unexpected response code %u\n",
- (unsigned int) response_code);
- GNUNET_break (0);
- response_code = 0;
- break;
- }
- if (NULL != rrh->reveal_cb)
- rrh->reveal_cb (rrh->reveal_cb_cls,
- response_code,
- TALER_JSON_get_error_code (j),
- 0,
- NULL,
- NULL,
- j);
- TALER_EXCHANGE_refresh_reveal_cancel (rrh);
-}
-
-
-/**
- * Submit a /refresh/reval request to the exchange and get the exchange's
- * response.
- *
- * This API is typically used by a wallet. Note that to ensure that
- * no money is lost in case of hardware failures, the provided
- * arguments should have been committed to persistent storage
- * prior to calling this function.
- *
- * @param exchange the exchange handle; the exchange must be ready to operate
- * @param refresh_data_length size of the @a refresh_data (returned
- * in the `res_size` argument from #TALER_EXCHANGE_refresh_prepare())
- * @param refresh_data the refresh data as returned from
- #TALER_EXCHANGE_refresh_prepare())
- * @param noreveal_index response from the exchange to the
- * #TALER_EXCHANGE_refresh_melt() invocation
- * @param reveal_cb the callback to call with the final result of the
- * refresh operation
- * @param reveal_cb_cls closure for the above callback
- * @return a handle for this request; NULL if the argument was invalid.
- * In this case, neither callback will be called.
- */
-struct TALER_EXCHANGE_RefreshRevealHandle *
-TALER_EXCHANGE_refresh_reveal (struct TALER_EXCHANGE_Handle *exchange,
- size_t refresh_data_length,
- const char *refresh_data,
- uint32_t noreveal_index,
- TALER_EXCHANGE_RefreshRevealCallback reveal_cb,
- void *reveal_cb_cls)
-{
- struct TALER_EXCHANGE_RefreshRevealHandle *rrh;
- json_t *transfer_privs;
- json_t *new_denoms_h;
- json_t *coin_evs;
- json_t *reveal_obj;
- json_t *link_sigs;
- CURL *eh;
- struct GNUNET_CURL_Context *ctx;
- struct MeltData *md;
- struct TALER_TransferPublicKeyP transfer_pub;
- char arg_str[sizeof (struct TALER_RefreshCommitmentP) * 2 + 32];
-
- if (noreveal_index >= TALER_CNC_KAPPA)
- {
- /* We check this here, as it would be really bad to below just
- disclose all the transfer keys. Note that this error should
- have been caught way earlier when the exchange replied, but maybe
- we had some internal corruption that changed the value... */
- GNUNET_break (0);
- return NULL;
- }
- if (GNUNET_YES !=
- TEAH_handle_is_ready (exchange))
- {
- GNUNET_break (0);
- return NULL;
- }
- md = deserialize_melt_data (refresh_data,
- refresh_data_length);
- if (NULL == md)
- {
- GNUNET_break (0);
- return NULL;
- }
-
- /* now transfer_pub */
- GNUNET_CRYPTO_ecdhe_key_get_public (
- &md->melted_coin.transfer_priv[noreveal_index].ecdhe_priv,
- &transfer_pub.ecdhe_pub);
-
- /* now new_denoms */
- GNUNET_assert (NULL != (new_denoms_h = json_array ()));
- GNUNET_assert (NULL != (coin_evs = json_array ()));
- GNUNET_assert (NULL != (link_sigs = json_array ()));
- for (unsigned int i = 0; i<md->num_fresh_coins; i++)
- {
- struct GNUNET_HashCode denom_hash;
- struct TALER_PlanchetDetail pd;
-
- GNUNET_CRYPTO_rsa_public_key_hash (md->fresh_pks[i].rsa_public_key,
- &denom_hash);
- GNUNET_assert (0 ==
- json_array_append_new (new_denoms_h,
- GNUNET_JSON_from_data_auto (
- &denom_hash)));
-
- if (GNUNET_OK !=
- TALER_planchet_prepare (&md->fresh_pks[i],
- &md->fresh_coins[noreveal_index][i],
- &pd))
- {
- /* This should have been noticed during the preparation stage. */
- GNUNET_break (0);
- json_decref (new_denoms_h);
- json_decref (coin_evs);
- return NULL;
- }
- GNUNET_assert (0 ==
- json_array_append_new (coin_evs,
- GNUNET_JSON_from_data (pd.coin_ev,
- pd.coin_ev_size)));
-
- /* compute link signature */
- {
- struct TALER_CoinSpendSignatureP link_sig;
- struct TALER_LinkDataPS ldp;
-
- ldp.purpose.size = htonl (sizeof (ldp));
- ldp.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_LINK);
- ldp.h_denom_pub = denom_hash;
- GNUNET_CRYPTO_eddsa_key_get_public (&md->melted_coin.coin_priv.eddsa_priv,
- &ldp.old_coin_pub.eddsa_pub);
- ldp.transfer_pub = transfer_pub;
- GNUNET_CRYPTO_hash (pd.coin_ev,
- pd.coin_ev_size,
- &ldp.coin_envelope_hash);
- GNUNET_assert (GNUNET_OK ==
- GNUNET_CRYPTO_eddsa_sign (
- &md->melted_coin.coin_priv.eddsa_priv,
- &ldp.purpose,
- &link_sig.eddsa_signature));
- GNUNET_assert (0 ==
- json_array_append_new (link_sigs,
- GNUNET_JSON_from_data_auto (
- &link_sig)));
- }
-
- GNUNET_free (pd.coin_ev);
- }
-
- /* build array of transfer private keys */
- GNUNET_assert (NULL != (transfer_privs = json_array ()));
- for (unsigned int j = 0; j<TALER_CNC_KAPPA; j++)
- {
- if (j == noreveal_index)
- {
- /* This is crucial: exclude the transfer key for the
- noreval index! */
- continue;
- }
- GNUNET_assert (0 ==
- json_array_append_new (transfer_privs,
- GNUNET_JSON_from_data_auto (
- &md->melted_coin.transfer_priv[j])));
- }
-
- /* build main JSON request */
- reveal_obj = json_pack ("{s:o, s:o, s:o, s:o, s:o}",
- "transfer_pub",
- GNUNET_JSON_from_data_auto (&transfer_pub),
- "transfer_privs",
- transfer_privs,
- "link_sigs",
- link_sigs,
- "new_denoms_h",
- new_denoms_h,
- "coin_evs",
- coin_evs);
- if (NULL == reveal_obj)
- {
- GNUNET_break (0);
- return NULL;
- }
-
- {
- char pub_str[sizeof (struct TALER_RefreshCommitmentP) * 2];
- char *end;
-
- end = GNUNET_STRINGS_data_to_string (&md->rc,
- sizeof (struct
- TALER_RefreshCommitmentP),
- pub_str,
- sizeof (pub_str));
- *end = '\0';
- GNUNET_snprintf (arg_str,
- sizeof (arg_str),
- "/refreshes/%s/reveal",
- pub_str);
- }
- /* finally, we can actually issue the request */
- rrh = GNUNET_new (struct TALER_EXCHANGE_RefreshRevealHandle);
- rrh->exchange = exchange;
- rrh->noreveal_index = noreveal_index;
- rrh->reveal_cb = reveal_cb;
- rrh->reveal_cb_cls = reveal_cb_cls;
- rrh->md = md;
- rrh->url = TEAH_path_to_url (rrh->exchange,
- arg_str);
-
- eh = TEL_curl_easy_get (rrh->url);
- if (GNUNET_OK !=
- TALER_curl_easy_post (&rrh->ctx,
- eh,
- reveal_obj))
- {
- GNUNET_break (0);
- curl_easy_cleanup (eh);
- json_decref (reveal_obj);
- GNUNET_free (rrh->url);
- GNUNET_free (rrh);
- return NULL;
- }
- json_decref (reveal_obj);
- ctx = TEAH_handle_to_context (rrh->exchange);
- rrh->job = GNUNET_CURL_job_add2 (ctx,
- eh,
- rrh->ctx.headers,
- &handle_refresh_reveal_finished,
- rrh);
- return rrh;
-}
-
-
-/**
- * Cancel a refresh reveal request. This function cannot be used
- * on a request handle if the callback was already invoked.
- *
- * @param rrh the refresh reval handle
- */
-void
-TALER_EXCHANGE_refresh_reveal_cancel (struct
- TALER_EXCHANGE_RefreshRevealHandle *rrh)
-{
- if (NULL != rrh->job)
- {
- GNUNET_CURL_job_cancel (rrh->job);
- rrh->job = NULL;
- }
- GNUNET_free (rrh->url);
- TALER_curl_easy_post_finished (&rrh->ctx);
- free_melt_data (rrh->md); /* does not free 'md' itself */
- GNUNET_free (rrh->md);
- GNUNET_free (rrh);
-}
-
-
-/* end of exchange_api_refresh.c */