/*
This file is part of TALER
Copyright (C) 2015 Christian Grothoff (and other contributing authors)
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, If not, see
*/
/**
* @file mint-lib/mint_api_refresh.c
* @brief Implementation of the /refresh/melt+reveal requests of the mint's HTTP API
* @author Christian Grothoff
*/
#include "platform.h"
#include
#include
#include /* just for HTTP status codes */
#include
#include "taler_mint_service.h"
#include "mint_api_json.h"
#include "mint_api_context.h"
#include "mint_api_handle.h"
#include "taler_signatures.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;
/**
* 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 deposit_valid_until;
/**
* 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 for serializations of coin-specific information about the
* fresh coins we generate during a melt.
*/
struct FreshCoinP
{
/**
* Private key of the coin.
*/
struct TALER_CoinSpendPrivateKeyP coin_priv;
/**
* Size of the encoded blinding key that follows.
*/
uint32_t bbuf_size;
/* Followed by serialization of:
- struct TALER_DenominationBlindingKey blinding_key;
*/
};
/**
* Header of serialized data about a melt operation, suitable for
* persisting it on disk.
*/
struct MeltDataP
{
/**
* Hash over the melting session.
*/
struct GNUNET_HashCode melt_session_hash;
/**
* Link secret used to encrypt the @a coin_priv and the blinding
* key in the linkage data for the respective cut-and-choose dimension.
*/
struct TALER_LinkSecretP link_secrets[TALER_CNC_KAPPA];
/**
* 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_MINT_DenomPublicKey fresh_pks[num_fresh_coins];
3) TALER_CNC_KAPPA times:
3a) struct FreshCoinP 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;
/**
* 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 deposit_valid_until;
/**
* Denomination key of the original coin.
*/
struct TALER_DenominationPublicKey pub_key;
/**
* Mint's signature over the coin.
*/
struct TALER_DenominationSignature sig;
};
/**
* Coin-specific information about the fresh coins we generate during
* a melt.
*/
struct FreshCoin
{
/**
* Private key of the coin.
*/
struct TALER_CoinSpendPrivateKeyP coin_priv;
/**
* Blinding key used for blinding during blind signing.
*/
struct TALER_DenominationBlindingKey blinding_key;
};
/**
* Melt data in non-serialized format for convenient processing.
*/
struct MeltData
{
/**
* Hash over the melting session.
*/
struct GNUNET_HashCode melt_session_hash;
/**
* Link secrets for each cut-and-choose dimension.
*/
struct TALER_LinkSecretP link_secrets[TALER_CNC_KAPPA];
/**
* Number of coins we are melting
*/
uint16_t num_melted_coins;
/**
* Number of coins we are creating
*/
uint16_t num_fresh_coins;
/**
* Information about the melted coins in an array of length @e
* num_melted_coins.
*/
struct MeltedCoin *melted_coins;
/**
* Array of @e num_fresh_coins denomination keys for the coins to be
* freshly minted.
*/
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 FreshCoin *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)
return;
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 fresh coin.
*
* @param fc fresh coin to release, the pointer itself is NOT
* freed (as it is typically not allocated by itself)
*/
static void
free_fresh_coin (struct FreshCoin *fc)
{
if (NULL == fc)
return;
if (NULL != fc->blinding_key.rsa_blinding_key)
GNUNET_CRYPTO_rsa_blinding_key_free (fc->blinding_key.rsa_blinding_key);
}
/**
* 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)
{
unsigned int i;
unsigned int j;
if (NULL != md->melted_coins)
{
for (i=0;inum_melted_coins;i++)
free_melted_coin (&md->melted_coins[i]);
GNUNET_free (md->melted_coins);
}
if (NULL != md->fresh_pks)
{
for (i=0;inum_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 (i=0;ifresh_coins)
{
for (j=0;jnum_fresh_coins;j++)
free_fresh_coin (&md->fresh_coins[i][j]);
GNUNET_free (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);
for (i=0;itransfer_priv[i];
mcp.deposit_valid_until = GNUNET_TIME_absolute_hton (mc->deposit_valid_until);
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);
for (i=0;itransfer_priv[i] = mcp.transfer_priv[i];
mc->deposit_valid_until = GNUNET_TIME_absolute_ntoh (mcp.deposit_valid_until);
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;
}
/**
* 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 FreshCoin *fc,
char *buf,
size_t off)
{
struct FreshCoinP fcp;
char *bbuf;
size_t bbuf_size;
bbuf_size = GNUNET_CRYPTO_rsa_blinding_key_encode (fc->blinding_key.rsa_blinding_key,
&bbuf);
if (NULL == buf)
{
GNUNET_free (bbuf);
return sizeof (struct FreshCoinP) + bbuf_size;
}
fcp.coin_priv = fc->coin_priv;
fcp.bbuf_size = htonl ((uint32_t) bbuf_size);
memcpy (&buf[off],
&fcp,
sizeof (struct FreshCoinP));
memcpy (&buf[off + sizeof (struct FreshCoinP)],
bbuf,
bbuf_size);
GNUNET_free (bbuf);
return sizeof (struct FreshCoinP) + bbuf_size;
}
/**
* 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 FreshCoin *fc,
const char *buf,
size_t size,
int *ok)
{
struct FreshCoinP fcp;
size_t bbuf_size;
if (size < sizeof (struct FreshCoinP))
{
GNUNET_break (0);
*ok = GNUNET_NO;
return 0;
}
memcpy (&fcp,
buf,
sizeof (struct FreshCoinP));
bbuf_size = ntohl (fcp.bbuf_size);
if (size < sizeof (struct FreshCoinP) + bbuf_size)
{
GNUNET_break (0);
*ok = GNUNET_NO;
return 0;
}
fc->blinding_key.rsa_blinding_key
= GNUNET_CRYPTO_rsa_blinding_key_decode (&buf[sizeof (struct FreshCoinP)],
bbuf_size);
if (NULL == fc->blinding_key.rsa_blinding_key)
{
GNUNET_break (0);
*ok = GNUNET_NO;
return 0;
}
fc->coin_priv = fcp.coin_priv;
return sizeof (struct FreshCoinP) + bbuf_size;
}
/**
* 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;
unsigned int i;
unsigned int j;
size = 0;
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->melt_session_hash = md->melt_session_hash;
for (i=0;ilink_secrets[i] = md->link_secrets[i];
mdp->num_melted_coins = htons (md->num_melted_coins);
mdp->num_fresh_coins = htons (md->num_fresh_coins);
}
for (i=0;inum_melted_coins;i++)
size += serialize_melted_coin (&md->melted_coins[i],
buf,
size);
for (i=0;inum_fresh_coins;i++)
size += serialize_denomination_key (&md->fresh_pks[i],
buf,
size);
for (i=0;inum_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;
unsigned int i;
unsigned int j;
size_t off;
int ok;
if (buf_size < sizeof (struct MeltDataP))
return NULL;
memcpy (&mdp,
buf,
buf_size);
md = GNUNET_new (struct MeltData);
md->melt_session_hash = mdp.melt_session_hash;
for (i=0;ilink_secrets[i] = mdp.link_secrets[i];
md->num_melted_coins = ntohs (mdp.num_melted_coins);
md->num_fresh_coins = ntohs (mdp.num_fresh_coins);
md->melted_coins = GNUNET_new_array (md->num_melted_coins,
struct MeltedCoin);
md->fresh_pks = GNUNET_new_array (md->num_fresh_coins,
struct TALER_DenominationPublicKey);
for (i=0;ifresh_coins[i] = GNUNET_new_array (md->num_fresh_coins,
struct FreshCoin);
off = sizeof (struct MeltDataP);
ok = GNUNET_YES;
for (i=0;(inum_melted_coins)&&(GNUNET_YES == ok);i++)
off += deserialize_melted_coin (&md->melted_coins[i],
&buf[off],
buf_size - off,
&ok);
for (i=0;(inum_fresh_coins)&&(GNUNET_YES == ok);i++)
off += deserialize_denomination_key (&md->fresh_pks[i],
&buf[off],
buf_size - off,
&ok);
for (i=0;inum_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;
}
/**
* Setup information for a fresh coin.
*
* @param[out] fc value to initialize
* @param pk denomination information for the fresh coin
*/
static void
setup_fresh_coin (struct FreshCoin *fc,
const struct TALER_MINT_DenomPublicKey *pk)
{
struct GNUNET_CRYPTO_EddsaPrivateKey *epk;
unsigned int len;
epk = GNUNET_CRYPTO_eddsa_key_create ();
fc->coin_priv.eddsa_priv = *epk;
GNUNET_free (epk);
len = GNUNET_CRYPTO_rsa_public_key_len (pk->key.rsa_public_key);
fc->blinding_key.rsa_blinding_key
= GNUNET_CRYPTO_rsa_blinding_key_create (len);
}
/**
* 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, is 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_MINT_refresh_execute() that will generate the request.
*
* This function does verify that the given request data is internally
* consistent. However, the @a melts_sigs are only verified if @a
* check_sigs is set to #GNUNET_YES, as this may be relatively
* expensive and should be redundant.
*
* 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 num_melts number of coins that are being melted (typically 1)
* @param melt_privs array of @a num_melts private keys of the coins to melt
* @param melt_amounts array of @a num_melts amounts specifying how much
* each coin will contribute to the melt (including fee)
* @param melt_sigs array of @a num_melts signatures affirming the
* validity of the public keys corresponding to the
* @a melt_privs private keys
* @param melt_pks array of @a num_melts denomination key information
* records corresponding to the @a melt_sigs
* validity of the keys
* @param check_sigs verify the validity of the signatures of @a melt_sigs
* @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 mint).
* Otherwise, pointer to a buffer of @a res_size to store persistently
* before proceeding to #TALER_MINT_refresh_execute().
* Non-null results should be freed using #GNUNET_free().
*/
char *
TALER_MINT_refresh_prepare (unsigned int num_melts,
const struct TALER_CoinSpendPrivateKeyP *melt_privs,
const struct TALER_Amount *melt_amounts,
const struct TALER_DenominationSignature *melt_sigs,
const struct TALER_MINT_DenomPublicKey *melt_pks,
int check_sigs,
unsigned int fresh_pks_len,
const struct TALER_MINT_DenomPublicKey *fresh_pks,
size_t *res_size)
{
struct MeltData md;
char *buf;
unsigned int i;
unsigned int j;
struct GNUNET_HashContext *hash_context;
for (i=0;icoin_priv.eddsa_priv,
&coin_pub.eddsa_pub);
GNUNET_CRYPTO_hash (&coin_pub.eddsa_pub,
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey),
&coin_hash);
coin_ev_size = GNUNET_CRYPTO_rsa_blind (&coin_hash,
fc->blinding_key.rsa_blinding_key,
md.fresh_pks[j].rsa_public_key,
&coin_ev);
GNUNET_CRYPTO_hash_context_read (hash_context,
coin_ev,
coin_ev_size);
GNUNET_free (coin_ev);
rld.coin_priv = fc->coin_priv;
rld.blinding_key = fc->blinding_key;
rle = TALER_refresh_encrypt (&rld,
&md.link_secrets[i]);
link_enc = TALER_refresh_link_encrypted_encode (rle,
&link_enc_size);
GNUNET_CRYPTO_hash_context_read (hash_context,
link_enc,
link_enc_size);
GNUNET_free (link_enc);
}
}
buf = serialize_melt_data (&md,
res_size);
free_melt_data (&md);
return buf;
}
/* ********************* /refresh/melt ***************************** */
/**
* @brief A /refresh/melt Handle
*/
struct TALER_MINT_RefreshMeltHandle
{
/**
* The connection to mint this request handle will use
*/
struct TALER_MINT_Handle *mint;
/**
* The url for this request.
*/
char *url;
/**
* JSON encoding of the request to POST.
*/
char *json_enc;
/**
* Handle for the request.
*/
struct MAC_Job *job;
/**
* Function to call with refresh melt failure results.
*/
TALER_MINT_RefreshMeltCallback melt_cb;
/**
* Closure for @e result_cb and @e melt_failure_cb.
*/
void *melt_cb_cls;
/**
* Download buffer
*/
struct MAC_DownloadBuffer db;
/**
* Actual information about the melt operation.
*/
struct MeltData *md;
};
/**
* Function called when we're done processing the
* HTTP /refresh/melt request.
*
* @param cls the `struct TALER_MINT_RefreshMeltHandle`
* @param eh the curl request handle
*/
static void
handle_refresh_melt_finished (void *cls,
CURL *eh)
{
struct TALER_MINT_RefreshMeltHandle *rmh = cls;
long response_code;
json_t *json;
rmh->job = NULL;
json = MAC_download_get_result (&rmh->db,
eh,
&response_code);
switch (response_code)
{
case 0:
break;
case MHD_HTTP_OK:
GNUNET_break (0); // FIXME: NOT implemented! (parse, check sig!)
break;
case MHD_HTTP_BAD_REQUEST:
/* This should never happen, either us or the mint is buggy
(or API version conflict); just pass JSON reply to the application */
break;
case MHD_HTTP_FORBIDDEN:
/* Double spending; check signatures on transaction history */
GNUNET_break (0); // FIXME: NOT implemented!
break;
case MHD_HTTP_UNAUTHORIZED:
/* Nothing really to verify, mint 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",
response_code);
GNUNET_break (0);
response_code = 0;
break;
}
if (NULL != rmh->melt_cb)
rmh->melt_cb (rmh->melt_cb_cls,
response_code,
UINT16_MAX,
json);
json_decref (json);
TALER_MINT_refresh_melt_cancel (rmh);
}
/**
* Convert a coin to be melted to the respective JSON encoding.
*
* @param melt_session_hash session hash to use
* @param mc coin to be melted
* @return JSON encoding of the melting request
*/
static json_t *
melted_coin_to_json (const struct GNUNET_HashCode *melt_session_hash,
const struct MeltedCoin *mc)
{
struct TALER_CoinSpendSignatureP confirm_sig;
struct TALER_RefreshMeltCoinAffirmationPS melt;
melt.purpose.purpose = htonl (TALER_SIGNATURE_MINT_CONFIRM_MELT);
melt.purpose.size = htonl (sizeof (melt));
melt.session_hash = *melt_session_hash;
TALER_amount_hton (&melt.amount_with_fee,
&mc->melt_amount_with_fee);
TALER_amount_hton (&melt.melt_fee,
&mc->fee_melt);
GNUNET_CRYPTO_eddsa_key_get_public (&mc->coin_priv.eddsa_priv,
&melt.coin_pub.eddsa_pub);
GNUNET_CRYPTO_eddsa_sign (&mc->coin_priv.eddsa_priv,
&melt.purpose,
&confirm_sig.eddsa_signature);
return json_pack ("{s:o, s:o, s:o, s:o, s:o}",
"coin_pub",
TALER_json_from_data (&melt.coin_pub,
sizeof (melt.coin_pub)),
"denom_pub",
TALER_json_from_rsa_public_key (mc->pub_key.rsa_public_key),
"denom_sig", 42,
TALER_json_from_rsa_signature (mc->sig.rsa_signature),
"confirm_sig",
TALER_json_from_data (&confirm_sig,
sizeof (confirm_sig)),
"value_with_fee",
TALER_json_from_amount (&mc->melt_amount_with_fee));
}
/**
* Submit a melt request to the mint and get the mint'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_MINT_refresh_prepare and committed to persistent storage
* prior to calling this function.
*
* @param mint the mint handle; the mint must be ready to operate
* @param refresh_data_length size of the @a refresh_data (returned
* in the `res_size` argument from #TALER_MINT_refresh_prepare())
* @param refresh_data the refresh data as returned from
#TALER_MINT_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_MINT_RefreshMeltHandle *
TALER_MINT_refresh_melt (struct TALER_MINT_Handle *mint,
size_t refresh_data_length,
const char *refresh_data,
TALER_MINT_RefreshMeltCallback melt_cb,
void *melt_cb_cls)
{
json_t *melt_obj;
json_t *new_denoms;
json_t *melt_coins;
json_t *coin_evs;
json_t *transfer_pubs;
json_t *secret_encs;
json_t *link_encs;
json_t *tmp;
struct TALER_MINT_RefreshMeltHandle *rmh;
CURL *eh;
struct TALER_MINT_Context *ctx;
struct MeltData *md;
unsigned int i;
unsigned int j;
if (GNUNET_YES !=
MAH_handle_is_ready (mint))
{
GNUNET_break (0);
return NULL;
}
md = deserialize_melt_data (refresh_data,
refresh_data_length);
if (NULL == md)
{
GNUNET_break (0);
return NULL;
}
/* build JSON request, each of the 6 arrays first */
new_denoms = json_array ();
melt_coins = json_array ();
coin_evs = json_array ();
transfer_pubs = json_array ();
secret_encs = json_array ();
link_encs = json_array ();
for (i=0;inum_melted_coins;i++)
{
const struct MeltedCoin *mc = &md->melted_coins[i];
/* now melt_coins */
json_array_append (melt_coins,
melted_coin_to_json (&md->melt_session_hash,
mc));
/* now transfer_pubs */
tmp = json_array ();
for (j=0;jtransfer_priv[j].ecdhe_priv,
&transfer_pub.ecdhe_pub);
json_array_append (tmp,
TALER_json_from_data (&transfer_pub,
sizeof (transfer_pub)));
}
json_array_append (transfer_pubs,
tmp);
/* now secret_encs */
tmp = json_array ();
for (j=0;jcoin_priv,
&mc->transfer_priv[j],
&trans_sec);
GNUNET_assert (GNUNET_OK ==
TALER_transfer_encrypt (&md->link_secrets[j],
&trans_sec,
&els));
json_array_append (tmp,
TALER_json_from_data (&els,
sizeof (els)));
}
json_array_append (secret_encs,
tmp);
}
for (i=0;inum_fresh_coins;i++)
{
/* now new_denoms */
json_array_append (new_denoms,
TALER_json_from_rsa_public_key
(md->fresh_pks[i].rsa_public_key));
/* now link_encs */
tmp = json_array ();
for (j=0;jfresh_coins[j][i];
struct TALER_RefreshLinkDecrypted rld;
struct TALER_RefreshLinkEncrypted *rle;
char *buf;
size_t buf_len;
rld.coin_priv = fc->coin_priv;
rld.blinding_key = fc->blinding_key;
rle = TALER_refresh_encrypt (&rld,
&md->link_secrets[j]);
GNUNET_assert (NULL != rle);
buf = TALER_refresh_link_encrypted_encode (rle,
&buf_len);
GNUNET_assert (NULL != buf);
json_array_append (tmp,
TALER_json_from_data (buf,
buf_len));
GNUNET_free (buf);
GNUNET_free (rle);
}
json_array_append (link_encs,
tmp);
/* now coin_evs */
tmp = json_array ();
for (j=0;jfresh_coins[j][i];
struct TALER_CoinSpendPublicKeyP coin_pub;
struct GNUNET_HashCode coin_hash;
char *coin_ev; /* blinded message to be signed (in envelope) for each coin */
size_t coin_ev_size;
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);
coin_ev_size = GNUNET_CRYPTO_rsa_blind (&coin_hash,
fc->blinding_key.rsa_blinding_key,
md->fresh_pks[j].rsa_public_key,
&coin_ev);
json_array_append (tmp,
TALER_json_from_data (coin_ev,
coin_ev_size));
GNUNET_free (coin_ev);
}
json_array_append (coin_evs,
tmp);
}
/* finally, assemble main JSON request from constitutent arrays */
melt_obj = json_pack ("{s:o, s:o, s:o, s:o, s:o, s:o}",
"new_denoms", new_denoms,
"melt_coins", melt_coins,
"coin_evs", coin_evs,
"transfer_pubs", transfer_pubs,
"secret_encs", secret_encs,
"link_encs", link_encs);
/* and now we can at last begin the actual request handling */
rmh = GNUNET_new (struct TALER_MINT_RefreshMeltHandle);
rmh->mint = mint;
rmh->melt_cb = melt_cb;
rmh->melt_cb_cls = melt_cb_cls;
rmh->md = md;
rmh->url = MAH_path_to_url (mint,
"/refresh/melt");
eh = curl_easy_init ();
GNUNET_assert (NULL != (rmh->json_enc =
json_dumps (melt_obj,
JSON_COMPACT)));
json_decref (melt_obj);
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_URL,
rmh->url));
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_POSTFIELDS,
rmh->json_enc));
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_POSTFIELDSIZE,
strlen (rmh->json_enc)));
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_WRITEFUNCTION,
&MAC_download_cb));
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_WRITEDATA,
&rmh->db));
ctx = MAH_handle_to_context (mint);
rmh->job = MAC_job_add (ctx,
eh,
GNUNET_YES,
&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_MINT_refresh_melt_cancel (struct TALER_MINT_RefreshMeltHandle *rmh)
{
if (NULL != rmh->job)
{
MAC_job_cancel (rmh->job);
rmh->job = NULL;
}
GNUNET_free_non_null (rmh->db.buf);
free_melt_data (rmh->md); /* does not free 'md' itself */
GNUNET_free (rmh->md);
GNUNET_free (rmh->url);
GNUNET_free (rmh->json_enc);
GNUNET_free (rmh);
}
/* ********************* /refresh/reveal ***************************** */
/**
* @brief A /refresh/reveal Handle
*/
struct TALER_MINT_RefreshRevealHandle
{
/**
* The connection to mint this request handle will use
*/
struct TALER_MINT_Handle *mint;
/**
* The url for this request.
*/
char *url;
/**
* JSON encoding of the request to POST.
*/
char *json_enc;
/**
* Handle for the request.
*/
struct MAC_Job *job;
/**
* Function to call with the result.
*/
TALER_MINT_RefreshRevealCallback reveal_cb;
/**
* Closure for @e reveal_cb.
*/
void *reveal_cb_cls;
/**
* Download buffer
*/
struct MAC_DownloadBuffer db;
/**
* Actual information about the melt operation.
*/
struct MeltData *md;
};
/**
* Function called when we're done processing the
* HTTP /refresh/reveal request.
*
* @param cls the `struct TALER_MINT_RefreshHandle`
* @param eh the curl request handle
*/
static void
handle_refresh_reveal_finished (void *cls,
CURL *eh)
{
struct TALER_MINT_RefreshRevealHandle *rrh = cls;
long response_code;
json_t *json;
rrh->job = NULL;
json = MAC_download_get_result (&rrh->db,
eh,
&response_code);
switch (response_code)
{
case 0:
break;
case MHD_HTTP_OK:
GNUNET_break (0); // FIXME: NOT implemented!
// rrh->reveal_cb = NULL; (call with real result, do not call again below)
break;
case MHD_HTTP_BAD_REQUEST:
/* This should never happen, either us or the mint is buggy
(or API version conflict); just pass JSON reply to the application */
break;
case MHD_HTTP_CONFLICT:
/* Nothing really to verify, mint 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",
response_code);
GNUNET_break (0);
response_code = 0;
break;
}
if (NULL != rrh->reveal_cb)
rrh->reveal_cb (rrh->reveal_cb_cls,
response_code,
0, NULL, NULL,
json);
json_decref (json);
TALER_MINT_refresh_reveal_cancel (rrh);
}
/**
* Submit a /refresh/reval request to the mint and get the mint'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 mint the mint handle; the mint must be ready to operate
* @param refresh_data_length size of the @a refresh_data (returned
* in the `res_size` argument from #TALER_MINT_refresh_prepare())
* @param refresh_data the refresh data as returned from
#TALER_MINT_refresh_prepare())
* @param noreveal_index response from the mint to the
* #TALER_MINT_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_MINT_RefreshRevealHandle *
TALER_MINT_refresh_reveal (struct TALER_MINT_Handle *mint,
size_t refresh_data_length,
const char *refresh_data,
uint16_t noreveal_index,
TALER_MINT_RefreshRevealCallback reveal_cb,
void *reveal_cb_cls)
{
struct TALER_MINT_RefreshRevealHandle *rrh;
json_t *reveal_obj;
CURL *eh;
struct TALER_MINT_Context *ctx;
struct MeltData *md;
if (GNUNET_YES !=
MAH_handle_is_ready (mint))
{
GNUNET_break (0);
return NULL;
}
md = deserialize_melt_data (refresh_data,
refresh_data_length);
if (NULL == md)
{
GNUNET_break (0);
return NULL;
}
/* FIXME: totally bogus request building here: */
reveal_obj = json_pack ("{s:o, s:O}", /* f/wire */
"4", 42,
"6", 62);
rrh = GNUNET_new (struct TALER_MINT_RefreshRevealHandle);
rrh->mint = mint;
rrh->reveal_cb = reveal_cb;
rrh->reveal_cb_cls = reveal_cb_cls;
rrh->md = md;
rrh->url = MAH_path_to_url (rrh->mint,
"/refresh/reveal");
eh = curl_easy_init ();
GNUNET_assert (NULL != (rrh->json_enc =
json_dumps (reveal_obj,
JSON_COMPACT)));
json_decref (reveal_obj);
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_URL,
rrh->url));
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_POSTFIELDS,
rrh->json_enc));
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_POSTFIELDSIZE,
strlen (rrh->json_enc)));
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_WRITEFUNCTION,
&MAC_download_cb));
GNUNET_assert (CURLE_OK ==
curl_easy_setopt (eh,
CURLOPT_WRITEDATA,
&rrh->db));
ctx = MAH_handle_to_context (rrh->mint);
rrh->job = MAC_job_add (ctx,
eh,
GNUNET_YES,
&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_MINT_refresh_reveal_cancel (struct TALER_MINT_RefreshRevealHandle *rrh)
{
if (NULL != rrh->job)
{
MAC_job_cancel (rrh->job);
rrh->job = NULL;
}
GNUNET_free_non_null (rrh->db.buf);
GNUNET_free (rrh->url);
GNUNET_free (rrh->json_enc);
free_melt_data (rrh->md); /* does not free 'md' itself */
GNUNET_free (rrh->md);
GNUNET_free (rrh);
}
/* end of mint_api_refresh.c */