remove c_hash from planchet detail where it does not logically belong

src/exchange/taler-exchange-httpd_refreshes_reveal.c

@@ -365,6 +365,7 @@ refreshes_reveal_transaction (void *cls,
           struct TALER_RefreshCoinData *rcd = &rce->new_coins[j];
           struct TALER_PlanchetSecretsP ps;
           struct TALER_PlanchetDetail pd;
+          struct GNUNET_HashCode c_hash;
 
           rcd->dk = &rctx->dkis[j]->denom_pub;
           TALER_planchet_setup_refresh (&ts,
@@ -373,6 +374,7 @@ refreshes_reveal_transaction (void *cls,
           GNUNET_assert (GNUNET_OK ==
                          TALER_planchet_prepare (rcd->dk,
                                                  &ps,
+                                                 &c_hash,
                                                  &pd));
           rcd->coin_ev = pd.coin_ev;
           rcd->coin_ev_size = pd.coin_ev_size;

src/include/taler_crypto_lib.h

@@ -445,13 +445,6 @@ struct TALER_PlanchetDetail
    */
   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!
    */
@@ -589,6 +582,7 @@ TALER_planchet_setup_random (struct TALER_PlanchetSecretsP *ps);
  *
  * @param dk denomination key for the coin to be created
  * @param ps secret planchet internals (for #TALER_planchet_to_coin)
+ * @param[out] c_hash set to the hash of the public key of the coin (needed later)
  * @param[out] pd set to the planchet detail for TALER_MERCHANT_tip_pickup() and
  *               other withdraw operations
  * @return #GNUNET_OK on success
@@ -596,6 +590,7 @@ TALER_planchet_setup_random (struct TALER_PlanchetSecretsP *ps);
 int
 TALER_planchet_prepare (const struct TALER_DenominationPublicKey *dk,
                         const struct TALER_PlanchetSecretsP *ps,
+                        struct GNUNET_HashCode *c_hash,
                         struct TALER_PlanchetDetail *pd);
 
 

src/lib/exchange_api_link.c

@@ -128,18 +128,21 @@ parse_link_coin (const struct TALER_EXCHANGE_LinkHandle *lh,
                                  rpub);
   /* verify link_sig */
   {
-    struct TALER_LinkDataPS ldp;
     struct TALER_PlanchetDetail pd;
+    struct GNUNET_HashCode c_hash;
+    struct TALER_LinkDataPS ldp = {
+      .purpose.size = htonl (sizeof (ldp)),
+      .purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_LINK),
+      .transfer_pub = *trans_pub
+    };
 
-    ldp.purpose.size = htonl (sizeof (ldp));
-    ldp.purpose.purpose = htonl (TALER_SIGNATURE_WALLET_COIN_LINK);
     GNUNET_CRYPTO_eddsa_key_get_public (&lh->coin_priv.eddsa_priv,
                                         &ldp.old_coin_pub.eddsa_pub);
-    ldp.transfer_pub = *trans_pub;
     pub->rsa_public_key = rpub;
     if (GNUNET_OK !=
         TALER_planchet_prepare (pub,
                                 &fc,
+                                &c_hash,
                                 &pd))
     {
       GNUNET_break (0);

src/lib/exchange_api_refresh_common.c

@@ -582,6 +582,7 @@ TALER_EXCHANGE_refresh_prepare (
       struct TALER_PlanchetSecretsP *fc = &md.fresh_coins[i][j];
       struct TALER_RefreshCoinData *rcd = &rce[i].new_coins[j];
       struct TALER_PlanchetDetail pd;
+      struct GNUNET_HashCode c_hash;
 
       TALER_planchet_setup_refresh (&trans_sec[i],
                                     j,
@@ -589,6 +590,7 @@ TALER_EXCHANGE_refresh_prepare (
       if (GNUNET_OK !=
           TALER_planchet_prepare (&md.fresh_pks[j],
                                   fc,
+                                  &c_hash,
                                   &pd))
       {
         GNUNET_break_op (0);

src/lib/exchange_api_refreshes_reveal.c

@@ -361,6 +361,7 @@ TALER_EXCHANGE_refreshes_reveal (
   {
     struct GNUNET_HashCode denom_hash;
     struct TALER_PlanchetDetail pd;
+    struct GNUNET_HashCode c_hash;
 
     GNUNET_CRYPTO_rsa_public_key_hash (md->fresh_pks[i].rsa_public_key,
                                        &denom_hash);
@@ -372,6 +373,7 @@ TALER_EXCHANGE_refreshes_reveal (
     if (GNUNET_OK !=
         TALER_planchet_prepare (&md->fresh_pks[i],
                                 &md->fresh_coins[noreveal_index][i],
+                                &c_hash,
                                 &pd))
     {
       /* This should have been noticed during the preparation stage. */

src/lib/exchange_api_withdraw.c

@@ -381,6 +381,7 @@ handle_reserve_withdraw_finished (void *cls,
  * @param ps secrets of the planchet
  *        caller must have committed this value to disk before the call (with @a pk)
  * @param pd planchet details matching @a ps
+ * @param c_hash hash over the coin's public key
  * @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
  * @return NULL
@@ -394,6 +395,7 @@ reserve_withdraw_internal (struct TALER_EXCHANGE_Handle *exchange,
                            const struct TALER_ReservePublicKeyP *reserve_pub,
                            const struct TALER_PlanchetSecretsP *ps,
                            const struct TALER_PlanchetDetail *pd,
+                           const struct GNUNET_HashCode *c_hash,
                            TALER_EXCHANGE_WithdrawCallback res_cb,
                            void *res_cb_cls)
 {
@@ -427,7 +429,7 @@ reserve_withdraw_internal (struct TALER_EXCHANGE_Handle *exchange,
   wh->pk.key.rsa_public_key
     = GNUNET_CRYPTO_rsa_public_key_dup (pk->key.rsa_public_key);
   wh->reserve_pub = *reserve_pub;
-  wh->c_hash = pd->c_hash;
+  wh->c_hash = *c_hash;
   GNUNET_CRYPTO_rsa_public_key_hash (pk->key.rsa_public_key,
                                      &h_denom_pub);
   withdraw_obj = json_pack ("{s:o, s:o," /* denom_pub_hash and coin_ev */
@@ -510,6 +512,7 @@ TALER_EXCHANGE_withdraw (
   struct TALER_WithdrawRequestPS req;
   struct TALER_PlanchetDetail pd;
   struct TALER_EXCHANGE_WithdrawHandle *wh;
+  struct GNUNET_HashCode c_hash;
 
   GNUNET_CRYPTO_eddsa_key_get_public (&reserve_priv->eddsa_priv,
                                       &req.reserve_pub.eddsa_pub);
@@ -531,6 +534,7 @@ TALER_EXCHANGE_withdraw (
   if (GNUNET_OK !=
       TALER_planchet_prepare (&pk->key,
                               ps,
+                              &c_hash,
                               &pd))
   {
     GNUNET_break_op (0);
@@ -549,6 +553,7 @@ TALER_EXCHANGE_withdraw (
                                   &req.reserve_pub,
                                   ps,
                                   &pd,
+                                  &c_hash,
                                   res_cb,
                                   res_cb_cls);
   GNUNET_free (pd.coin_ev);
@@ -589,11 +594,13 @@ TALER_EXCHANGE_withdraw2 (
   void *res_cb_cls)
 {
   struct TALER_EXCHANGE_WithdrawHandle *wh;
+  struct GNUNET_HashCode c_hash;
   struct TALER_PlanchetDetail pd;
 
   if (GNUNET_OK !=
       TALER_planchet_prepare (&pk->key,
                               ps,
+                              &c_hash,
                               &pd))
   {
     GNUNET_break_op (0);
@@ -605,6 +612,7 @@ TALER_EXCHANGE_withdraw2 (
                                   reserve_pub,
                                   ps,
                                   &pd,
+                                  &c_hash,
                                   res_cb,
                                   res_cb_cls);
   GNUNET_free (pd.coin_ev);

src/util/crypto.c

@@ -226,6 +226,7 @@ TALER_planchet_setup_random (struct TALER_PlanchetSecretsP *ps)
  *
  * @param dk denomination key for the coin to be created
  * @param ps secret planchet internals (for #TALER_planchet_to_coin)
+ * @param[out] c_hash set to the hash of the public key of the coin (needed later)
  * @param[out] pd set to the planchet detail for TALER_MERCHANT_tip_pickup() and
  *               other withdraw operations
  * @return #GNUNET_OK on success
@@ -233,6 +234,7 @@ TALER_planchet_setup_random (struct TALER_PlanchetSecretsP *ps)
 int
 TALER_planchet_prepare (const struct TALER_DenominationPublicKey *dk,
                         const struct TALER_PlanchetSecretsP *ps,
+                        struct GNUNET_HashCode *c_hash,
                         struct TALER_PlanchetDetail *pd)
 {
   struct TALER_CoinSpendPublicKeyP coin_pub;
@@ -241,9 +243,9 @@ TALER_planchet_prepare (const struct TALER_DenominationPublicKey *dk,
                                       &coin_pub.eddsa_pub);
   GNUNET_CRYPTO_hash (&coin_pub.eddsa_pub,
                       sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey),
-                      &pd->c_hash);
+                      c_hash);
   if (GNUNET_YES !=
-      GNUNET_CRYPTO_rsa_blind (&pd->c_hash,
+      GNUNET_CRYPTO_rsa_blind (c_hash,
                                &ps->blinding_key.bks,
                                dk->rsa_public_key,
                                &pd->coin_ev,