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major API refactoring, adding planchet generation and coin extraction APIs to the Taler crypto library, thereby simplifying code in withdraw, refresh, tipping, payback and testcases; slight API incompatibilities to previous versions are introduced

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Christian Grothoff 2017-10-31 14:02:54 +01:00
parent ec8146de92
commit 2f2930f1ba
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GPG Key ID: 939E6BE1E29FC3CC
11 changed files with 418 additions and 242 deletions
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6
ChangeLog
View File

@ -1,3 +1,9 @@
Tue Oct 31 13:43:55 CET 2017
Extended crypto API to provide planchet generation functions
explicitly (to be used on withdraw, refresh and tipping).
Renamed a few API calls to better reflect their functions.
Changed a few function signatures to use new structs. -CG
Wed Oct 18 15:20:29 CEST 2017 Wed Oct 18 15:20:29 CEST 2017
Releasing Taler v0.4.0. -CG Releasing Taler v0.4.0. -CG

6
src/benchmark/taler-exchange-benchmark.c
View File

@ -981,6 +981,7 @@ withdraw_coin (struct Coin *coin)
struct TALER_Amount left; struct TALER_Amount left;
const struct TALER_EXCHANGE_Keys *keys; const struct TALER_EXCHANGE_Keys *keys;
struct Reserve *r; struct Reserve *r;
struct TALER_PlanchetSecretsP ps;
keys = TALER_EXCHANGE_get_keys (exchange); keys = TALER_EXCHANGE_get_keys (exchange);
r = &reserves[coin->reserve_index]; r = &reserves[coin->reserve_index];
@ -996,12 +997,13 @@ withdraw_coin (struct Coin *coin)
GNUNET_assert (NULL != (coin->pk = find_pk (keys, &amount))); GNUNET_assert (NULL != (coin->pk = find_pk (keys, &amount)));
if (warm >= WARM_THRESHOLD) if (warm >= WARM_THRESHOLD)
num_withdraw++; num_withdraw++;
ps.coin_priv = coin->coin_priv;
ps.blinding_key = blinding_key;
coin->wsh = coin->wsh =
TALER_EXCHANGE_reserve_withdraw (exchange, TALER_EXCHANGE_reserve_withdraw (exchange,
coin->pk, coin->pk,
&r->reserve_priv, &r->reserve_priv,
&coin->coin_priv, &ps,
&blinding_key,
&reserve_withdraw_cb, &reserve_withdraw_cb,
coin); coin);
GNUNET_assert (GNUNET_SYSERR != GNUNET_assert (GNUNET_SYSERR !=

14
src/exchange-lib/exchange_api_payback.c
View File

@ -260,8 +260,7 @@ handle_payback_finished (void *cls,
* @param exchange the exchange handle; the exchange must be ready to operate * @param exchange the exchange handle; the exchange must be ready to operate
* @param pk kind of coin to pay back * @param pk kind of coin to pay back
* @param denom_sig signature over the coin by the exchange using @a pk * @param denom_sig signature over the coin by the exchange using @a pk
* @param coin_priv the coin's private key, * @param ps secret internals of the original planchet
* @param blinding_key where to fetch the coin's blinding key
* @param payback_cb the callback to call when the final result for this request is available * @param payback_cb the callback to call when the final result for this request is available
* @param payback_cb_cls closure for @a payback_cb * @param payback_cb_cls closure for @a payback_cb
* @return NULL * @return NULL
@ -272,8 +271,7 @@ struct TALER_EXCHANGE_PaybackHandle *
TALER_EXCHANGE_payback (struct TALER_EXCHANGE_Handle *exchange, TALER_EXCHANGE_payback (struct TALER_EXCHANGE_Handle *exchange,
const struct TALER_EXCHANGE_DenomPublicKey *pk, const struct TALER_EXCHANGE_DenomPublicKey *pk,
const struct TALER_DenominationSignature *denom_sig, const struct TALER_DenominationSignature *denom_sig,
const struct TALER_CoinSpendPrivateKeyP *coin_priv, const struct TALER_PlanchetSecretsP *ps,
const struct TALER_DenominationBlindingKeyP *blinding_key,
TALER_EXCHANGE_PaybackResultCallback payback_cb, TALER_EXCHANGE_PaybackResultCallback payback_cb,
void *payback_cb_cls) void *payback_cb_cls)
{ {
@ -288,12 +286,12 @@ TALER_EXCHANGE_payback (struct TALER_EXCHANGE_Handle *exchange,
MAH_handle_is_ready (exchange)); MAH_handle_is_ready (exchange));
pr.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_PAYBACK); pr.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_PAYBACK);
pr.purpose.size = htonl (sizeof (struct TALER_PaybackRequestPS)); pr.purpose.size = htonl (sizeof (struct TALER_PaybackRequestPS));
GNUNET_CRYPTO_eddsa_key_get_public (&coin_priv->eddsa_priv, GNUNET_CRYPTO_eddsa_key_get_public (&ps->coin_priv.eddsa_priv,
&pr.coin_pub.eddsa_pub); &pr.coin_pub.eddsa_pub);
pr.h_denom_pub = pk->h_key; pr.h_denom_pub = pk->h_key;
pr.coin_blind = *blinding_key; pr.coin_blind = ps->blinding_key;
GNUNET_assert (GNUNET_OK == GNUNET_assert (GNUNET_OK ==
GNUNET_CRYPTO_eddsa_sign (&coin_priv->eddsa_priv, GNUNET_CRYPTO_eddsa_sign (&ps->coin_priv.eddsa_priv,
&pr.purpose, &pr.purpose,
&coin_sig.eddsa_signature)); &coin_sig.eddsa_signature));
@ -304,7 +302,7 @@ TALER_EXCHANGE_payback (struct TALER_EXCHANGE_Handle *exchange,
"denom_sig", GNUNET_JSON_from_rsa_signature (denom_sig->rsa_signature), "denom_sig", GNUNET_JSON_from_rsa_signature (denom_sig->rsa_signature),
"coin_pub", GNUNET_JSON_from_data_auto (&pr.coin_pub), "coin_pub", GNUNET_JSON_from_data_auto (&pr.coin_pub),
"coin_sig", GNUNET_JSON_from_data_auto (&coin_sig), "coin_sig", GNUNET_JSON_from_data_auto (&coin_sig),
"coin_blind_key_secret", GNUNET_JSON_from_data_auto (blinding_key) "coin_blind_key_secret", GNUNET_JSON_from_data_auto (&ps->blinding_key)
); );
if (NULL == payback_obj) if (NULL == payback_obj)
{ {

113
src/exchange-lib/exchange_api_refresh.c
View File

@ -236,18 +236,16 @@ free_melted_coin (struct MeltedCoin *mc)
static void static void
free_melt_data (struct MeltData *md) free_melt_data (struct MeltData *md)
{ {
unsigned int i;
free_melted_coin (&md->melted_coin); free_melted_coin (&md->melted_coin);
if (NULL != md->fresh_pks) if (NULL != md->fresh_pks)
{ {
for (i=0;i<md->num_fresh_coins;i++) for (unsigned int i=0;i<md->num_fresh_coins;i++)
if (NULL != md->fresh_pks[i].rsa_public_key) if (NULL != md->fresh_pks[i].rsa_public_key)
GNUNET_CRYPTO_rsa_public_key_free (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); GNUNET_free (md->fresh_pks);
} }
for (i=0;i<TALER_CNC_KAPPA;i++) for (unsigned int i=0;i<TALER_CNC_KAPPA;i++)
GNUNET_free (md->fresh_coins[i]); GNUNET_free (md->fresh_coins[i]);
/* Finally, clean up a bit... /* Finally, clean up a bit...
(NOTE: compilers might optimize this away, so this is (NOTE: compilers might optimize this away, so this is
@ -600,8 +598,6 @@ deserialize_melt_data (const char *buf,
{ {
struct MeltData *md; struct MeltData *md;
struct MeltDataP mdp; struct MeltDataP mdp;
unsigned int i;
unsigned int j;
size_t off; size_t off;
int ok; int ok;
@ -615,7 +611,7 @@ deserialize_melt_data (const char *buf,
md->num_fresh_coins = ntohs (mdp.num_fresh_coins); md->num_fresh_coins = ntohs (mdp.num_fresh_coins);
md->fresh_pks = GNUNET_new_array (md->num_fresh_coins, md->fresh_pks = GNUNET_new_array (md->num_fresh_coins,
struct TALER_DenominationPublicKey); struct TALER_DenominationPublicKey);
for (i=0;i<TALER_CNC_KAPPA;i++) for (unsigned int i=0;i<TALER_CNC_KAPPA;i++)
md->fresh_coins[i] = GNUNET_new_array (md->num_fresh_coins, md->fresh_coins[i] = GNUNET_new_array (md->num_fresh_coins,
struct TALER_PlanchetSecretsP); struct TALER_PlanchetSecretsP);
off = sizeof (struct MeltDataP); off = sizeof (struct MeltDataP);
@ -624,14 +620,14 @@ deserialize_melt_data (const char *buf,
&buf[off], &buf[off],
buf_size - off, buf_size - off,
&ok); &ok);
for (i=0;(i<md->num_fresh_coins)&&(GNUNET_YES == ok);i++) for (unsigned int i=0;(i<md->num_fresh_coins)&&(GNUNET_YES == ok);i++)
off += deserialize_denomination_key (&md->fresh_pks[i], off += deserialize_denomination_key (&md->fresh_pks[i],
&buf[off], &buf[off],
buf_size - off, buf_size - off,
&ok); &ok);
for (i=0;i<TALER_CNC_KAPPA;i++) for (unsigned int i=0;i<TALER_CNC_KAPPA;i++)
for(j=0;(j<md->num_fresh_coins)&&(GNUNET_YES == ok);j++) for (unsigned int j=0;(j<md->num_fresh_coins)&&(GNUNET_YES == ok);j++)
off += deserialize_fresh_coin (&md->fresh_coins[i][j], off += deserialize_fresh_coin (&md->fresh_coins[i][j],
&buf[off], &buf[off],
buf_size - off, buf_size - off,
@ -704,8 +700,6 @@ TALER_EXCHANGE_refresh_prepare (const struct TALER_CoinSpendPrivateKeyP *melt_pr
{ {
struct MeltData md; struct MeltData md;
char *buf; char *buf;
unsigned int i;
unsigned int j;
struct GNUNET_HashContext *hash_context; struct GNUNET_HashContext *hash_context;
struct TALER_Amount total; struct TALER_Amount total;
struct TALER_CoinSpendPublicKeyP coin_pub; struct TALER_CoinSpendPublicKeyP coin_pub;
@ -715,7 +709,7 @@ TALER_EXCHANGE_refresh_prepare (const struct TALER_CoinSpendPrivateKeyP *melt_pr
&coin_pub.eddsa_pub); &coin_pub.eddsa_pub);
hash_context = GNUNET_CRYPTO_hash_context_start (); hash_context = GNUNET_CRYPTO_hash_context_start ();
/* build up melt data structure */ /* build up melt data structure */
for (i=0;i<TALER_CNC_KAPPA;i++) for (unsigned int i=0;i<TALER_CNC_KAPPA;i++)
{ {
struct GNUNET_CRYPTO_EcdhePrivateKey *tpk; struct GNUNET_CRYPTO_EcdhePrivateKey *tpk;
struct TALER_TransferPublicKeyP tp; struct TALER_TransferPublicKeyP tp;
@ -747,14 +741,14 @@ TALER_EXCHANGE_refresh_prepare (const struct TALER_CoinSpendPrivateKeyP *melt_pr
= GNUNET_CRYPTO_rsa_signature_dup (melt_sig->rsa_signature); = GNUNET_CRYPTO_rsa_signature_dup (melt_sig->rsa_signature);
md.fresh_pks = GNUNET_new_array (fresh_pks_len, md.fresh_pks = GNUNET_new_array (fresh_pks_len,
struct TALER_DenominationPublicKey); struct TALER_DenominationPublicKey);
for (i=0;i<fresh_pks_len;i++) for (unsigned int i=0;i<fresh_pks_len;i++)
md.fresh_pks[i].rsa_public_key md.fresh_pks[i].rsa_public_key
= GNUNET_CRYPTO_rsa_public_key_dup (fresh_pks[i].key.rsa_public_key); = GNUNET_CRYPTO_rsa_public_key_dup (fresh_pks[i].key.rsa_public_key);
for (i=0;i<TALER_CNC_KAPPA;i++) for (unsigned int i=0;i<TALER_CNC_KAPPA;i++)
{ {
md.fresh_coins[i] = GNUNET_new_array (fresh_pks_len, md.fresh_coins[i] = GNUNET_new_array (fresh_pks_len,
struct TALER_PlanchetSecretsP); struct TALER_PlanchetSecretsP);
for (j=0;j<fresh_pks_len;j++) for (unsigned int j=0;j<fresh_pks_len;j++)
{ {
TALER_planchet_setup_refresh (&trans_sec[i], TALER_planchet_setup_refresh (&trans_sec[i],
j, j,
@ -766,7 +760,7 @@ TALER_EXCHANGE_refresh_prepare (const struct TALER_CoinSpendPrivateKeyP *melt_pr
GNUNET_assert (GNUNET_OK == GNUNET_assert (GNUNET_OK ==
TALER_amount_get_zero (melt_amount->currency, TALER_amount_get_zero (melt_amount->currency,
&total)); &total));
for (j=0;j<fresh_pks_len;j++) for (unsigned int j=0;j<fresh_pks_len;j++)
{ {
if ( (GNUNET_OK != if ( (GNUNET_OK !=
TALER_amount_add (&total, TALER_amount_add (&total,
@ -795,7 +789,7 @@ TALER_EXCHANGE_refresh_prepare (const struct TALER_CoinSpendPrivateKeyP *melt_pr
/* next, add all of the hashes from the denomination keys to the /* next, add all of the hashes from the denomination keys to the
hash_context */ hash_context */
for (i=0;i<fresh_pks_len;i++) for (unsigned int i=0;i<fresh_pks_len;i++)
{ {
char *buf; char *buf;
size_t buf_size; size_t buf_size;
@ -820,28 +814,18 @@ TALER_EXCHANGE_refresh_prepare (const struct TALER_CoinSpendPrivateKeyP *melt_pr
sizeof (struct TALER_AmountNBO)); sizeof (struct TALER_AmountNBO));
} }
for (i = 0; i < TALER_CNC_KAPPA; i++) for (unsigned int i = 0; i < TALER_CNC_KAPPA; i++)
{ {
for (j = 0; j < fresh_pks_len; j++) for (unsigned int j = 0; j < fresh_pks_len; j++)
{ {
const struct TALER_PlanchetSecretsP *fc; /* coin this is about */ const struct TALER_PlanchetSecretsP *fc; /* coin this is about */
struct TALER_CoinSpendPublicKeyP coin_pub; struct TALER_PlanchetDetail pd;
struct GNUNET_HashCode coin_hash;
char *coin_ev; /* blinded message to be signed (in envelope) for each coin */
size_t coin_ev_size;
fc = &md.fresh_coins[i][j]; fc = &md.fresh_coins[i][j];
GNUNET_CRYPTO_eddsa_key_get_public (&fc->coin_priv.eddsa_priv, if (GNUNET_OK !=
&coin_pub.eddsa_pub); TALER_planchet_prepare (&md.fresh_pks[j],
GNUNET_CRYPTO_hash (&coin_pub.eddsa_pub, fc,
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey), &pd))
&coin_hash);
if (GNUNET_YES !=
GNUNET_CRYPTO_rsa_blind (&coin_hash,
&fc->blinding_key.bks,
md.fresh_pks[j].rsa_public_key,
&coin_ev,
&coin_ev_size))
{ {
GNUNET_break_op (0); GNUNET_break_op (0);
GNUNET_CRYPTO_hash_context_abort (hash_context); GNUNET_CRYPTO_hash_context_abort (hash_context);
@ -849,9 +833,9 @@ TALER_EXCHANGE_refresh_prepare (const struct TALER_CoinSpendPrivateKeyP *melt_pr
return NULL; return NULL;
} }
GNUNET_CRYPTO_hash_context_read (hash_context, GNUNET_CRYPTO_hash_context_read (hash_context,
coin_ev, pd.coin_ev,
coin_ev_size); pd.coin_ev_size);
GNUNET_free (coin_ev); GNUNET_free (pd.coin_ev);
} }
} }
GNUNET_CRYPTO_hash_context_finish (hash_context, GNUNET_CRYPTO_hash_context_finish (hash_context,
@ -1294,22 +1278,12 @@ TALER_EXCHANGE_refresh_melt (struct TALER_EXCHANGE_Handle *exchange,
for (i=0;i<md->num_fresh_coins;i++) for (i=0;i<md->num_fresh_coins;i++)
{ {
const struct TALER_PlanchetSecretsP *fc = &md->fresh_coins[j][i]; const struct TALER_PlanchetSecretsP *fc = &md->fresh_coins[j][i];
struct TALER_CoinSpendPublicKeyP coin_pub; struct TALER_PlanchetDetail pd;
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, if (GNUNET_OK !=
&coin_pub.eddsa_pub); TALER_planchet_prepare (&md->fresh_pks[i],
GNUNET_CRYPTO_hash (&coin_pub.eddsa_pub, fc,
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey), &pd))
&coin_hash);
if (GNUNET_YES !=
GNUNET_CRYPTO_rsa_blind (&coin_hash,
&fc->blinding_key.bks,
md->fresh_pks[i].rsa_public_key,
&coin_ev,
&coin_ev_size))
{ {
/* This should have been noticed during the preparation stage. */ /* This should have been noticed during the preparation stage. */
GNUNET_break (0); GNUNET_break (0);
@ -1322,9 +1296,9 @@ TALER_EXCHANGE_refresh_melt (struct TALER_EXCHANGE_Handle *exchange,
} }
GNUNET_assert (0 == GNUNET_assert (0 ==
json_array_append_new (tmp, json_array_append_new (tmp,
GNUNET_JSON_from_data (coin_ev, GNUNET_JSON_from_data (pd.coin_ev,
coin_ev_size))); pd.coin_ev_size)));
GNUNET_free (coin_ev); GNUNET_free (pd.coin_ev);
} }
GNUNET_assert (0 == GNUNET_assert (0 ==
json_array_append_new (coin_evs, json_array_append_new (coin_evs,
@ -1510,13 +1484,13 @@ refresh_reveal_ok (struct TALER_EXCHANGE_RefreshRevealHandle *rrh,
struct TALER_DenominationPublicKey *pk; struct TALER_DenominationPublicKey *pk;
json_t *jsonai; json_t *jsonai;
struct GNUNET_CRYPTO_RsaSignature *blind_sig; struct GNUNET_CRYPTO_RsaSignature *blind_sig;
struct GNUNET_CRYPTO_RsaSignature *sig;
struct TALER_CoinSpendPublicKeyP coin_pub; struct TALER_CoinSpendPublicKeyP coin_pub;
struct GNUNET_HashCode coin_hash; struct GNUNET_HashCode coin_hash;
struct GNUNET_JSON_Specification spec[] = { struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_rsa_signature ("ev_sig", &blind_sig), GNUNET_JSON_spec_rsa_signature ("ev_sig", &blind_sig),
GNUNET_JSON_spec_end() GNUNET_JSON_spec_end()
}; };
struct TALER_FreshCoin coin;
fc = &rrh->md->fresh_coins[rrh->noreveal_index][i]; fc = &rrh->md->fresh_coins[rrh->noreveal_index][i];
pk = &rrh->md->fresh_pks[i]; pk = &rrh->md->fresh_pks[i];
@ -1533,31 +1507,28 @@ refresh_reveal_ok (struct TALER_EXCHANGE_RefreshRevealHandle *rrh,
return GNUNET_SYSERR; return GNUNET_SYSERR;
} }
/* unblind the signature */ /* needed to verify the signature, and we didn't store it earlier,
sig = GNUNET_CRYPTO_rsa_unblind (blind_sig, hence recomputing it here... */
&fc->blinding_key.bks,
pk->rsa_public_key);
GNUNET_CRYPTO_rsa_signature_free (blind_sig);
/* verify the signature */
GNUNET_CRYPTO_eddsa_key_get_public (&fc->coin_priv.eddsa_priv, GNUNET_CRYPTO_eddsa_key_get_public (&fc->coin_priv.eddsa_priv,
&coin_pub.eddsa_pub); &coin_pub.eddsa_pub);
GNUNET_CRYPTO_hash (&coin_pub.eddsa_pub, GNUNET_CRYPTO_hash (&coin_pub.eddsa_pub,
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey), sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey),
&coin_hash); &coin_hash);
if (GNUNET_OK != if (GNUNET_OK !=
GNUNET_CRYPTO_rsa_verify (&coin_hash, TALER_planchet_to_coin (pk,
sig, blind_sig,
pk->rsa_public_key)) fc,
&coin_hash,
&coin))
{ {
GNUNET_break_op (0); GNUNET_break_op (0);
GNUNET_CRYPTO_rsa_signature_free (sig); GNUNET_CRYPTO_rsa_signature_free (blind_sig);
GNUNET_JSON_parse_free (outer_spec); GNUNET_JSON_parse_free (outer_spec);
return GNUNET_SYSERR; return GNUNET_SYSERR;
} }
coin_privs[i] = fc->coin_priv; GNUNET_CRYPTO_rsa_signature_free (blind_sig);
sigs[i].rsa_signature = sig; coin_privs[i] = coin.coin_priv;
sigs[i] = coin.sig;
} }
GNUNET_JSON_parse_free (outer_spec); GNUNET_JSON_parse_free (outer_spec);
return GNUNET_OK; return GNUNET_OK;

82
src/exchange-lib/exchange_api_reserve.c
View File

@ -693,9 +693,9 @@ struct TALER_EXCHANGE_ReserveWithdrawHandle
TALER_EXCHANGE_ReserveWithdrawResultCallback cb; TALER_EXCHANGE_ReserveWithdrawResultCallback cb;
/** /**
* Key used to blind the value. * Secrets of the planchet.
*/ */
struct TALER_DenominationBlindingKeyP blinding_key; struct TALER_PlanchetSecretsP ps;
/** /**
* Denomination key we are withdrawing. * Denomination key we are withdrawing.
@ -739,8 +739,7 @@ reserve_withdraw_ok (struct TALER_EXCHANGE_ReserveWithdrawHandle *wsh,
const json_t *json) const json_t *json)
{ {
struct GNUNET_CRYPTO_RsaSignature *blind_sig; struct GNUNET_CRYPTO_RsaSignature *blind_sig;
struct GNUNET_CRYPTO_RsaSignature *sig; struct TALER_FreshCoin fc;
struct TALER_DenominationSignature dsig;
struct GNUNET_JSON_Specification spec[] = { struct GNUNET_JSON_Specification spec[] = {
GNUNET_JSON_spec_rsa_signature ("ev_sig", &blind_sig), GNUNET_JSON_spec_rsa_signature ("ev_sig", &blind_sig),
GNUNET_JSON_spec_end() GNUNET_JSON_spec_end()
@ -754,29 +753,28 @@ reserve_withdraw_ok (struct TALER_EXCHANGE_ReserveWithdrawHandle *wsh,
GNUNET_break_op (0); GNUNET_break_op (0);
return GNUNET_SYSERR; return GNUNET_SYSERR;
} }
sig = GNUNET_CRYPTO_rsa_unblind (blind_sig,
&wsh->blinding_key.bks,
wsh->pk->key.rsa_public_key);
GNUNET_CRYPTO_rsa_signature_free (blind_sig);
if (GNUNET_OK != if (GNUNET_OK !=
GNUNET_CRYPTO_rsa_verify (&wsh->c_hash, TALER_planchet_to_coin (&wsh->pk->key,
sig, blind_sig,
wsh->pk->key.rsa_public_key)) &wsh->ps,
&wsh->c_hash,
&fc))
{ {
GNUNET_break_op (0); GNUNET_break_op (0);
GNUNET_CRYPTO_rsa_signature_free (sig); GNUNET_JSON_parse_free (spec);
return GNUNET_SYSERR; return GNUNET_SYSERR;
} }
GNUNET_JSON_parse_free (spec);
/* signature is valid, return it to the application */ /* signature is valid, return it to the application */
dsig.rsa_signature = sig;
wsh->cb (wsh->cb_cls, wsh->cb (wsh->cb_cls,
MHD_HTTP_OK, MHD_HTTP_OK,
TALER_EC_NONE, TALER_EC_NONE,
&dsig, &fc.sig,
json); json);
/* make sure callback isn't called again after return */ /* make sure callback isn't called again after return */
wsh->cb = NULL; wsh->cb = NULL;
GNUNET_CRYPTO_rsa_signature_free (sig); GNUNET_CRYPTO_rsa_signature_free (fc.sig.rsa_signature);
return GNUNET_OK; return GNUNET_OK;
} }
@ -978,9 +976,7 @@ handle_reserve_withdraw_finished (void *cls,
* @param exchange the exchange handle; the exchange must be ready to operate * @param exchange the exchange handle; the exchange must be ready to operate
* @param pk kind of coin to create * @param pk kind of coin to create
* @param reserve_priv private key of the reserve to withdraw from * @param reserve_priv private key of the reserve to withdraw from
* @param coin_priv where to fetch the coin's private key, * @param ps secrets of the planchet
* caller must have committed this value to disk before the call (with @a pk)
* @param blinding_key where to fetch the coin's blinding key
* caller must have committed this value to disk before the call (with @a pk) * caller must have committed this value to disk before the call (with @a pk)
* @param res_cb the callback to call when the final result for this request is available * @param res_cb the callback to call when the final result for this request is available
* @param res_cb_cls closure for the above callback * @param res_cb_cls closure for the above callback
@ -992,44 +988,33 @@ struct TALER_EXCHANGE_ReserveWithdrawHandle *
TALER_EXCHANGE_reserve_withdraw (struct TALER_EXCHANGE_Handle *exchange, TALER_EXCHANGE_reserve_withdraw (struct TALER_EXCHANGE_Handle *exchange,
const struct TALER_EXCHANGE_DenomPublicKey *pk, const struct TALER_EXCHANGE_DenomPublicKey *pk,
const struct TALER_ReservePrivateKeyP *reserve_priv, const struct TALER_ReservePrivateKeyP *reserve_priv,
const struct TALER_CoinSpendPrivateKeyP *coin_priv, const struct TALER_PlanchetSecretsP *ps,
const struct TALER_DenominationBlindingKeyP *blinding_key,
TALER_EXCHANGE_ReserveWithdrawResultCallback res_cb, TALER_EXCHANGE_ReserveWithdrawResultCallback res_cb,
void *res_cb_cls) void *res_cb_cls)
{ {
struct TALER_EXCHANGE_ReserveWithdrawHandle *wsh; struct TALER_EXCHANGE_ReserveWithdrawHandle *wsh;
struct TALER_WithdrawRequestPS req; struct TALER_WithdrawRequestPS req;
struct TALER_ReserveSignatureP reserve_sig; struct TALER_ReserveSignatureP reserve_sig;
struct TALER_CoinSpendPublicKeyP coin_pub;
struct GNUNET_CURL_Context *ctx; struct GNUNET_CURL_Context *ctx;
struct TALER_Amount amount_with_fee; struct TALER_Amount amount_with_fee;
char *coin_ev;
size_t coin_ev_size;
json_t *withdraw_obj; json_t *withdraw_obj;
CURL *eh; CURL *eh;
struct TALER_PlanchetDetail pd;
if (GNUNET_OK !=
TALER_planchet_prepare (&pk->key,
ps,
&pd))
{
GNUNET_break_op (0);
return NULL;
}
wsh = GNUNET_new (struct TALER_EXCHANGE_ReserveWithdrawHandle); wsh = GNUNET_new (struct TALER_EXCHANGE_ReserveWithdrawHandle);
wsh->exchange = exchange; wsh->exchange = exchange;
wsh->cb = res_cb; wsh->cb = res_cb;
wsh->cb_cls = res_cb_cls; wsh->cb_cls = res_cb_cls;
wsh->pk = pk; wsh->pk = pk;
wsh->c_hash = pd.c_hash;
GNUNET_CRYPTO_eddsa_key_get_public (&coin_priv->eddsa_priv,
&coin_pub.eddsa_pub);
GNUNET_CRYPTO_hash (&coin_pub.eddsa_pub,
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey),
&wsh->c_hash);
if (GNUNET_YES !=
GNUNET_CRYPTO_rsa_blind (&wsh->c_hash,
&blinding_key->bks,
pk->key.rsa_public_key,
&coin_ev,
&coin_ev_size))
{
GNUNET_break_op (0);
GNUNET_free (wsh);
return NULL;
}
GNUNET_CRYPTO_eddsa_key_get_public (&reserve_priv->eddsa_priv, GNUNET_CRYPTO_eddsa_key_get_public (&reserve_priv->eddsa_priv,
&wsh->reserve_pub.eddsa_pub); &wsh->reserve_pub.eddsa_pub);
req.purpose.size = htonl (sizeof (struct TALER_WithdrawRequestPS)); req.purpose.size = htonl (sizeof (struct TALER_WithdrawRequestPS));
@ -1042,7 +1027,7 @@ TALER_EXCHANGE_reserve_withdraw (struct TALER_EXCHANGE_Handle *exchange,
{ {
/* exchange gave us denomination keys that overflow like this!? */ /* exchange gave us denomination keys that overflow like this!? */
GNUNET_break_op (0); GNUNET_break_op (0);
GNUNET_free (coin_ev); GNUNET_free (pd.coin_ev);
GNUNET_free (wsh); GNUNET_free (wsh);
return NULL; return NULL;
} }
@ -1050,10 +1035,9 @@ TALER_EXCHANGE_reserve_withdraw (struct TALER_EXCHANGE_Handle *exchange,
&amount_with_fee); &amount_with_fee);
TALER_amount_hton (&req.withdraw_fee, TALER_amount_hton (&req.withdraw_fee,
&pk->fee_withdraw); &pk->fee_withdraw);
GNUNET_CRYPTO_rsa_public_key_hash (pk->key.rsa_public_key, req.h_denomination_pub = pd.denom_pub_hash;
&req.h_denomination_pub); GNUNET_CRYPTO_hash (pd.coin_ev,
GNUNET_CRYPTO_hash (coin_ev, pd.coin_ev_size,
coin_ev_size,
&req.h_coin_envelope); &req.h_coin_envelope);
GNUNET_assert (GNUNET_OK == GNUNET_assert (GNUNET_OK ==
GNUNET_CRYPTO_eddsa_sign (&reserve_priv->eddsa_priv, GNUNET_CRYPTO_eddsa_sign (&reserve_priv->eddsa_priv,
@ -1062,11 +1046,11 @@ TALER_EXCHANGE_reserve_withdraw (struct TALER_EXCHANGE_Handle *exchange,
withdraw_obj = json_pack ("{s:o, s:o," /* denom_pub and coin_ev */ withdraw_obj = json_pack ("{s:o, s:o," /* denom_pub and coin_ev */
" s:o, s:o}",/* reserve_pub and reserve_sig */ " s:o, s:o}",/* reserve_pub and reserve_sig */
"denom_pub", GNUNET_JSON_from_rsa_public_key (pk->key.rsa_public_key), "denom_pub", GNUNET_JSON_from_rsa_public_key (pk->key.rsa_public_key),
"coin_ev", GNUNET_JSON_from_data (coin_ev, "coin_ev", GNUNET_JSON_from_data (pd.coin_ev,
coin_ev_size), pd.coin_ev_size),
"reserve_pub", GNUNET_JSON_from_data_auto (&wsh->reserve_pub), "reserve_pub", GNUNET_JSON_from_data_auto (&wsh->reserve_pub),
"reserve_sig", GNUNET_JSON_from_data_auto (&reserve_sig)); "reserve_sig", GNUNET_JSON_from_data_auto (&reserve_sig));
GNUNET_free (coin_ev); GNUNET_free (pd.coin_ev);
if (NULL == withdraw_obj) if (NULL == withdraw_obj)
{ {
GNUNET_break (0); GNUNET_break (0);
@ -1074,7 +1058,7 @@ TALER_EXCHANGE_reserve_withdraw (struct TALER_EXCHANGE_Handle *exchange,
} }
wsh->blinding_key = *blinding_key; wsh->ps = *ps;
wsh->url = MAH_path_to_url (exchange, "/reserve/withdraw"); wsh->url = MAH_path_to_url (exchange, "/reserve/withdraw");
eh = curl_easy_init (); eh = curl_easy_init ();

38
src/exchange-lib/test_exchange_api.c
View File

@ -341,14 +341,9 @@ struct Command
struct TALER_DenominationSignature sig; struct TALER_DenominationSignature sig;
/** /**
* Set (by the interpreter) to the coin's private key. * Private key material of the coin, set by the interpreter.
*/ */
struct TALER_CoinSpendPrivateKeyP coin_priv; struct TALER_PlanchetSecretsP ps;
/**
* Blinding key used for the operation.
*/
struct TALER_DenominationBlindingKeyP blinding_key;
/** /**
* Withdraw handle (while operation is running). * Withdraw handle (while operation is running).
@ -1984,7 +1979,7 @@ get_public_key_from_coin_command (const struct Command *coin,
switch (coin->oc) switch (coin->oc)
{ {
case OC_WITHDRAW_SIGN: case OC_WITHDRAW_SIGN:
GNUNET_CRYPTO_eddsa_key_get_public (&coin->details.reserve_withdraw.coin_priv.eddsa_priv, GNUNET_CRYPTO_eddsa_key_get_public (&coin->details.reserve_withdraw.ps.coin_priv.eddsa_priv,
&coin_pub->eddsa_pub); &coin_pub->eddsa_pub);
break; break;
case OC_REFRESH_REVEAL: case OC_REFRESH_REVEAL:
@ -2016,7 +2011,6 @@ interpreter_run (void *cls)
struct Command *cmd = &is->commands[is->ip]; struct Command *cmd = &is->commands[is->ip];
const struct Command *ref; const struct Command *ref;
struct TALER_ReservePublicKeyP reserve_pub; struct TALER_ReservePublicKeyP reserve_pub;
struct TALER_CoinSpendPublicKeyP coin_pub;
struct TALER_Amount amount; struct TALER_Amount amount;
struct GNUNET_TIME_Absolute execution_date; struct GNUNET_TIME_Absolute execution_date;
json_t *sender_details; json_t *sender_details;
@ -2165,25 +2159,12 @@ interpreter_run (void *cls)
return; return;
} }
/* create coin's private key */ TALER_planchet_setup_random (&cmd->details.reserve_withdraw.ps);
{
struct GNUNET_CRYPTO_EddsaPrivateKey *priv;
priv = GNUNET_CRYPTO_eddsa_key_create ();
cmd->details.reserve_withdraw.coin_priv.eddsa_priv = *priv;
GNUNET_free (priv);
}
GNUNET_CRYPTO_eddsa_key_get_public (&cmd->details.reserve_withdraw.coin_priv.eddsa_priv,
&coin_pub.eddsa_pub);
GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_WEAK,
&cmd->details.reserve_withdraw.blinding_key,
sizeof (cmd->details.reserve_withdraw.blinding_key));
cmd->details.reserve_withdraw.wsh cmd->details.reserve_withdraw.wsh
= TALER_EXCHANGE_reserve_withdraw (exchange, = TALER_EXCHANGE_reserve_withdraw (exchange,
cmd->details.reserve_withdraw.pk, cmd->details.reserve_withdraw.pk,
&ref->details.admin_add_incoming.reserve_priv, &ref->details.admin_add_incoming.reserve_priv,
&cmd->details.reserve_withdraw.coin_priv, &cmd->details.reserve_withdraw.ps,
&cmd->details.reserve_withdraw.blinding_key,
&reserve_withdraw_cb, &reserve_withdraw_cb,
is); is);
if (NULL == cmd->details.reserve_withdraw.wsh) if (NULL == cmd->details.reserve_withdraw.wsh)
@ -2217,7 +2198,7 @@ interpreter_run (void *cls)
switch (ref->oc) switch (ref->oc)
{ {
case OC_WITHDRAW_SIGN: case OC_WITHDRAW_SIGN:
coin_priv = &ref->details.reserve_withdraw.coin_priv; coin_priv = &ref->details.reserve_withdraw.ps.coin_priv;
coin_pk = ref->details.reserve_withdraw.pk; coin_pk = ref->details.reserve_withdraw.pk;
coin_pk_sig = &ref->details.reserve_withdraw.sig; coin_pk_sig = &ref->details.reserve_withdraw.sig;
break; break;
@ -2376,7 +2357,7 @@ interpreter_run (void *cls)
GNUNET_assert (NULL != ref); GNUNET_assert (NULL != ref);
GNUNET_assert (OC_WITHDRAW_SIGN == ref->oc); GNUNET_assert (OC_WITHDRAW_SIGN == ref->oc);
melt_priv = ref->details.reserve_withdraw.coin_priv; melt_priv = ref->details.reserve_withdraw.ps.coin_priv;
if (GNUNET_OK != if (GNUNET_OK !=
TALER_string_to_amount (md->amount, TALER_string_to_amount (md->amount,
&melt_amount)) &melt_amount))
@ -2478,7 +2459,7 @@ interpreter_run (void *cls)
/* finally, use private key from withdraw sign command */ /* finally, use private key from withdraw sign command */
cmd->details.refresh_link.rlh cmd->details.refresh_link.rlh
= TALER_EXCHANGE_refresh_link (exchange, = TALER_EXCHANGE_refresh_link (exchange,
&ref->details.reserve_withdraw.coin_priv, &ref->details.reserve_withdraw.ps.coin_priv,
&link_cb, &link_cb,
is); is);
if (NULL == cmd->details.refresh_link.rlh) if (NULL == cmd->details.refresh_link.rlh)
@ -2745,8 +2726,7 @@ interpreter_run (void *cls)
= TALER_EXCHANGE_payback (exchange, = TALER_EXCHANGE_payback (exchange,
ref->details.reserve_withdraw.pk, ref->details.reserve_withdraw.pk,
&ref->details.reserve_withdraw.sig, &ref->details.reserve_withdraw.sig,
&ref->details.reserve_withdraw.coin_priv, &ref->details.reserve_withdraw.ps,
&ref->details.reserve_withdraw.blinding_key,
&payback_cb, &payback_cb,
is); is);
return; return;

180
src/include/taler_crypto_lib.h
View File

@ -396,7 +396,83 @@ int
TALER_test_coin_valid (const struct TALER_CoinPublicInfo *coin_public_info); TALER_test_coin_valid (const struct TALER_CoinPublicInfo *coin_public_info);
/* ****************** Refresh crypto primitives ************* */ GNUNET_NETWORK_STRUCT_BEGIN
/**
* Header for serializations of coin-specific information about the
* fresh coins we generate. These are the secrets that arise during
* planchet generation, which is the first stage of creating a new
* coin.
*/
struct TALER_PlanchetSecretsP
{
/**
* Private key of the coin.
*/
struct TALER_CoinSpendPrivateKeyP coin_priv;
/**
* The blinding key.
*/
struct TALER_DenominationBlindingKeyP blinding_key;
};
GNUNET_NETWORK_STRUCT_END
/**
* Details about a planchet that the customer wants to obtain
* a withdrawal authorization. This is the information that
* will need to be sent to the exchange to obtain the blind
* signature required to turn a planchet into a coin.
*/
struct TALER_PlanchetDetail
{
/**
* Hash of the denomination public key.
*/
struct GNUNET_HashCode denom_pub_hash;
/**
* Hash of the coin's public key. Kept around so we do not need to
* compute it again. Can be recomputed by hashing the public key
* of @a coin_priv if storage is at a premium.
*/
struct GNUNET_HashCode c_hash;
/**
* Blinded coin (see GNUNET_CRYPTO_rsa_blind()). Note: is malloc()'ed!
*/
char *coin_ev;
/**
* Number of bytes in @a coin_ev.
*/
size_t coin_ev_size;
};
/**
* Information about a (fresh) coin, returned from the API when we
* finished creating a coin. Note that @e sig needs to be freed
* using the appropriate code.
*/
struct TALER_FreshCoin
{
/**
* The exchange's signature over the coin's public key.
*/
struct TALER_DenominationSignature sig;
/**
* The coin's private key.
*/
struct TALER_CoinSpendPrivateKeyP coin_priv;
};
GNUNET_NETWORK_STRUCT_BEGIN GNUNET_NETWORK_STRUCT_BEGIN
@ -426,6 +502,7 @@ struct TALER_TransferSecretP
*/ */
#define TALER_WIRE_TRANSFER_IDENTIFIER_LEN_STR "32" #define TALER_WIRE_TRANSFER_IDENTIFIER_LEN_STR "32"
/** /**
* Raw value of a wire transfer subjects, without the checksum. * Raw value of a wire transfer subjects, without the checksum.
*/ */
@ -472,6 +549,68 @@ struct TALER_WireTransferIdentifierP
GNUNET_NETWORK_STRUCT_END GNUNET_NETWORK_STRUCT_END
/**
* Setup information for a fresh coin, deriving the coin private key
* and the blinding factor from the @a secret_seed with a KDF salted
* by the @a coin_num_salt.
*
* @param secret_seed seed to use for KDF to derive coin keys
* @param coin_num_salt number of the coin to include in KDF
* @param[out] fc value to initialize
*/
void
TALER_planchet_setup_refresh (const struct TALER_TransferSecretP *secret_seed,
unsigned int coin_num_salt,
struct TALER_PlanchetSecretsP *fc);
/**
* Setup information for a fresh coin.
*
* @param[out] ps value to initialize
*/
void
TALER_planchet_setup_random (struct TALER_PlanchetSecretsP *ps);
/**
* Prepare a planchet for tipping. Creates and blinds a coin.
*
* @param dk denomination key for the coin to be created
* @param ps secret planchet internals (for #TALER_planchet_to_coin)
* @param[out] pd set to the planchet detail for TALER_MERCHANT_tip_pickup() and
* other withdraw operations
* @return #GNUNET_OK on success
*/
int
TALER_planchet_prepare (const struct TALER_DenominationPublicKey *dk,
const struct TALER_PlanchetSecretsP *ps,
struct TALER_PlanchetDetail *pd);
/**
* Obtain a coin from the planchet's secrets and the blind signature
* of the exchange.
*
* @param dk denomination key, must match what was given to #TALER_planchet_prepare()
* @param blind_sig blind signature from the exchange
* @param ps secrets from #TALER_planchet_prepare()
* @param c_hash hash of the coin's public key for verification of the signature
* @param[out] coin set to the details of the fresh coin
* @return #GNUNET_OK on success
*/
int
TALER_planchet_to_coin (const struct TALER_DenominationPublicKey *dk,
const struct GNUNET_CRYPTO_RsaSignature *blind_sig,
const struct TALER_PlanchetSecretsP *ps,
const struct GNUNET_HashCode *c_hash,
struct TALER_FreshCoin *coin);
/* ****************** Refresh crypto primitives ************* */
/** /**
* Given the coin and the transfer private keys, compute the * Given the coin and the transfer private keys, compute the
* transfer secret. (Technically, we only need one of the two * transfer secret. (Technically, we only need one of the two
@ -516,44 +655,5 @@ TALER_link_recover_transfer_secret (const struct TALER_TransferPublicKeyP *trans
const struct TALER_CoinSpendPrivateKeyP *coin_priv, const struct TALER_CoinSpendPrivateKeyP *coin_priv,
struct TALER_TransferSecretP *transfer_secret); struct TALER_TransferSecretP *transfer_secret);
GNUNET_NETWORK_STRUCT_BEGIN
/**
* Header for serializations of coin-specific information about the
* fresh coins we generate during a melt.
*/
struct TALER_PlanchetSecretsP
{
/**
* Private key of the coin.
*/
struct TALER_CoinSpendPrivateKeyP coin_priv;
/**
* The blinding key.
*/
struct TALER_DenominationBlindingKeyP blinding_key;
};
GNUNET_NETWORK_STRUCT_END
/**
* Setup information for a fresh coin, deriving the coin private key
* and the blinding factor from the @a secret_seed with a KDF salted
* by the @a coin_num_salt.
*
* @param secret_seed seed to use for KDF to derive coin keys
* @param coin_num_salt number of the coin to include in KDF
* @param[out] fc value to initialize
*/
void
TALER_planchet_setup_refresh (const struct TALER_TransferSecretP *secret_seed,
unsigned int coin_num_salt,
struct TALER_PlanchetSecretsP *fc);
#endif #endif

13
src/include/taler_exchange_service.h
View File

@ -976,9 +976,7 @@ typedef void
* @param exchange the exchange handle; the exchange must be ready to operate * @param exchange the exchange handle; the exchange must be ready to operate
* @param pk kind of coin to create * @param pk kind of coin to create
* @param reserve_priv private key of the reserve to withdraw from * @param reserve_priv private key of the reserve to withdraw from
* @param coin_priv where to fetch the coin's private key, * @param ps secrets of the planchet
* caller must have committed this value to disk before the call (with @a pk)
* @param blinding_key where to fetch the coin's blinding key
* caller must have committed this value to disk before the call (with @a pk) * caller must have committed this value to disk before the call (with @a pk)
* @param res_cb the callback to call when the final result for this request is available * @param res_cb the callback to call when the final result for this request is available
* @param res_cb_cls closure for @a res_cb * @param res_cb_cls closure for @a res_cb
@ -990,8 +988,7 @@ struct TALER_EXCHANGE_ReserveWithdrawHandle *
TALER_EXCHANGE_reserve_withdraw (struct TALER_EXCHANGE_Handle *exchange, TALER_EXCHANGE_reserve_withdraw (struct TALER_EXCHANGE_Handle *exchange,
const struct TALER_EXCHANGE_DenomPublicKey *pk, const struct TALER_EXCHANGE_DenomPublicKey *pk,
const struct TALER_ReservePrivateKeyP *reserve_priv, const struct TALER_ReservePrivateKeyP *reserve_priv,
const struct TALER_CoinSpendPrivateKeyP *coin_priv, const struct TALER_PlanchetSecretsP *ps,
const struct TALER_DenominationBlindingKeyP *blinding_key,
TALER_EXCHANGE_ReserveWithdrawResultCallback res_cb, TALER_EXCHANGE_ReserveWithdrawResultCallback res_cb,
void *res_cb_cls); void *res_cb_cls);
@ -1540,8 +1537,7 @@ typedef void
* @param exchange the exchange handle; the exchange must be ready to operate * @param exchange the exchange handle; the exchange must be ready to operate
* @param pk kind of coin to pay back * @param pk kind of coin to pay back
* @param denom_sig signature over the coin by the exchange using @a pk * @param denom_sig signature over the coin by the exchange using @a pk
* @param coin_priv the coin's private key, * @param ps secret internals of the original planchet
* @param blinding_key where to fetch the coin's blinding key
* @param payback_cb the callback to call when the final result for this request is available * @param payback_cb the callback to call when the final result for this request is available
* @param payback_cb_cls closure for @a payback_cb * @param payback_cb_cls closure for @a payback_cb
* @return NULL * @return NULL
@ -1552,8 +1548,7 @@ struct TALER_EXCHANGE_PaybackHandle *
TALER_EXCHANGE_payback (struct TALER_EXCHANGE_Handle *exchange, TALER_EXCHANGE_payback (struct TALER_EXCHANGE_Handle *exchange,
const struct TALER_EXCHANGE_DenomPublicKey *pk, const struct TALER_EXCHANGE_DenomPublicKey *pk,
const struct TALER_DenominationSignature *denom_sig, const struct TALER_DenominationSignature *denom_sig,
const struct TALER_CoinSpendPrivateKeyP *coin_priv, const struct TALER_PlanchetSecretsP *ps,
const struct TALER_DenominationBlindingKeyP *blinding_key,
TALER_EXCHANGE_PaybackResultCallback payback_cb, TALER_EXCHANGE_PaybackResultCallback payback_cb,
void *payback_cb_cls); void *payback_cb_cls);

2
src/include/taler_util.h
View File

@ -134,6 +134,4 @@ const struct GNUNET_OS_ProjectData *
TALER_project_data_default (void); TALER_project_data_default (void);
#endif #endif

143
src/util/crypto.c
View File

@ -171,35 +171,19 @@ TALER_link_recover_transfer_secret (const struct TALER_TransferPublicKeyP *trans
/** /**
* Setup information for a fresh coin. * Set the bits in the private EdDSA key so that they match
* the specification.
* *
* @param secret_seed seed to use for KDF to derive coin keys * @param[in,out] pk private key to patch
* @param coin_num_salt number of the coin to include in KDF
* @param[out] fc value to initialize
*/ */
void static void
TALER_planchet_setup_refresh (const struct TALER_TransferSecretP *secret_seed, patch_private_key (struct GNUNET_CRYPTO_EddsaPrivateKey *pk)
unsigned int coin_num_salt,
struct TALER_PlanchetSecretsP *fc)
{ {
uint32_t be_salt = htonl (coin_num_salt); uint8_t *p = (uint8_t *) pk;
uint8_t *p;
GNUNET_assert (GNUNET_OK ==
GNUNET_CRYPTO_kdf (fc,
sizeof (*fc),
&be_salt,
sizeof (be_salt),
secret_seed,
sizeof (*secret_seed),
"taler-coin-derivation",
strlen ("taler-coin-derivation"),
NULL, 0));
/* Taken from like 170-172 of libgcrypt/cipher/ecc.c /* Taken from like 170-172 of libgcrypt/cipher/ecc.c
* We note that libgcrypt stores the private key in the reverse order * We note that libgcrypt stores the private key in the reverse order
* from many Ed25519 implementatons. */ * from many Ed25519 implementatons. */
p = (uint8_t *) &(fc->coin_priv);
p[0] &= 0x7f; /* Clear bit 255. */ p[0] &= 0x7f; /* Clear bit 255. */
p[0] |= 0x40; /* Set bit 254. */ p[0] |= 0x40; /* Set bit 254. */
p[31] &= 0xf8; /* Clear bits 2..0 so that d mod 8 == 0 */ p[31] &= 0xf8; /* Clear bits 2..0 so that d mod 8 == 0 */
@ -213,6 +197,121 @@ TALER_planchet_setup_refresh (const struct TALER_TransferSecretP *secret_seed,
} }
/**
* Setup information for a fresh coin.
*
* @param secret_seed seed to use for KDF to derive coin keys
* @param coin_num_salt number of the coin to include in KDF
* @param[out] ps value to initialize
*/
void
TALER_planchet_setup_refresh (const struct TALER_TransferSecretP *secret_seed,
unsigned int coin_num_salt,
struct TALER_PlanchetSecretsP *ps)
{
uint32_t be_salt = htonl (coin_num_salt);
GNUNET_assert (GNUNET_OK ==
GNUNET_CRYPTO_kdf (ps,
sizeof (*ps),
&be_salt,
sizeof (be_salt),
secret_seed,
sizeof (*secret_seed),
"taler-coin-derivation",
strlen ("taler-coin-derivation"),
NULL, 0));
patch_private_key (&ps->coin_priv.eddsa_priv);
}
/**
* Setup information for a fresh coin.
*
* @param[out] ps value to initialize
*/
void
TALER_planchet_setup_random (struct TALER_PlanchetSecretsP *ps)
{
GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_STRONG,
ps,
sizeof (*ps));
patch_private_key (&ps->coin_priv.eddsa_priv);
}
/**
* Prepare a planchet for tipping. Creates and blinds a coin.
*
* @param dk denomination key for the coin to be created
* @param ps secret planchet internals (for #TALER_planchet_to_coin)
* @param[out] pd set to the planchet detail for TALER_MERCHANT_tip_pickup() and
* other withdraw operations
* @return #GNUNET_OK on success
*/
int
TALER_planchet_prepare (const struct TALER_DenominationPublicKey *dk,
const struct TALER_PlanchetSecretsP *ps,
struct TALER_PlanchetDetail *pd)
{
struct TALER_CoinSpendPublicKeyP coin_pub;
GNUNET_CRYPTO_eddsa_key_get_public (&ps->coin_priv.eddsa_priv,
&coin_pub.eddsa_pub);
GNUNET_CRYPTO_hash (&coin_pub.eddsa_pub,
sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey),
&pd->c_hash);
if (GNUNET_YES !=
GNUNET_CRYPTO_rsa_blind (&pd->c_hash,
&ps->blinding_key.bks,
dk->rsa_public_key,
&pd->coin_ev,
&pd->coin_ev_size))
{
GNUNET_break_op (0);
return GNUNET_SYSERR;
}
GNUNET_CRYPTO_rsa_public_key_hash (dk->rsa_public_key,
&pd->denom_pub_hash);
return GNUNET_OK;
}
/**
* Obtain a coin from the planchet's secrets and the blind signature
* of the exchange.
*
* @param dk denomination key, must match what was given to #TALER_planchet_prepare()
* @param blind_sig blind signature from the exchange
* @param ps secrets from #TALER_planchet_prepare()
* @param c_hash hash of the coin's public key for verification of the signature
* @param[out] coin set to the details of the fresh coin
* @return #GNUNET_OK on success
*/
int
TALER_planchet_to_coin (const struct TALER_DenominationPublicKey *dk,
const struct GNUNET_CRYPTO_RsaSignature *blind_sig,
const struct TALER_PlanchetSecretsP *ps,
const struct GNUNET_HashCode *c_hash,
struct TALER_FreshCoin *coin)
{
struct GNUNET_CRYPTO_RsaSignature *sig;
sig = GNUNET_CRYPTO_rsa_unblind (blind_sig,
&ps->blinding_key.bks,
dk->rsa_public_key);
if (GNUNET_OK !=
GNUNET_CRYPTO_rsa_verify (c_hash,
sig,
dk->rsa_public_key))
{
GNUNET_break_op (0);
GNUNET_CRYPTO_rsa_signature_free (sig);
return GNUNET_SYSERR;
}
coin->sig.rsa_signature = sig;
coin->coin_priv = ps->coin_priv;
return GNUNET_OK;
}
/* end of crypto.c */ /* end of crypto.c */

43
src/util/test_crypto.c
View File

@ -84,12 +84,55 @@ test_high_level ()
} }
/**
* Test the basic planchet functionality of creating a fresh planchet
* and extracting the respective signature.
*
* @return 0 on success
*/
static int
test_planchets ()
{
struct TALER_PlanchetSecretsP ps;
struct TALER_DenominationPrivateKey dk_priv;
struct TALER_DenominationPublicKey dk_pub;
struct TALER_PlanchetDetail pd;
struct GNUNET_CRYPTO_RsaSignature *blind_sig;
struct TALER_FreshCoin coin;
dk_priv.rsa_private_key = GNUNET_CRYPTO_rsa_private_key_create (1024);
dk_pub.rsa_public_key = GNUNET_CRYPTO_rsa_private_key_get_public (dk_priv.rsa_private_key);
TALER_planchet_setup_random (&ps);
GNUNET_assert (GNUNET_OK ==
TALER_planchet_prepare (&dk_pub,
&ps,
&pd));
blind_sig = GNUNET_CRYPTO_rsa_sign_blinded (dk_priv.rsa_private_key,
pd.coin_ev,
pd.coin_ev_size);
GNUNET_assert (NULL != blind_sig);
GNUNET_assert (GNUNET_OK ==
TALER_planchet_to_coin (&dk_pub,
blind_sig,
&ps,
&pd.c_hash,
&coin));
GNUNET_CRYPTO_rsa_signature_free (blind_sig);
GNUNET_CRYPTO_rsa_signature_free (coin.sig.rsa_signature);
GNUNET_CRYPTO_rsa_private_key_free (dk_priv.rsa_private_key);
GNUNET_CRYPTO_rsa_public_key_free (dk_pub.rsa_public_key);
return 0;
}
int int
main(int argc, main(int argc,
const char *const argv[]) const char *const argv[])
{ {
if (0 != test_high_level ()) if (0 != test_high_level ())
return 1; return 1;
if (0 != test_planchets ())
return 1;
return 0; return 0;
} }