marking remaining FIXMEs for #3516

src/mint-lib/mint_api_deposit.c

@@ -92,6 +92,16 @@ struct TALER_MINT_DepositHandle
    */
   struct TALER_DepositConfirmationPS depconf;
 
+  /**
+   * Value of the /deposit transaction, including fee.
+   */
+  struct TALER_Amount amount_with_fee;
+
+  /**
+   * Total value of the coin being transacted with.
+   */
+  struct TALER_Amount coin_value;
+
   /**
    * The size of the download buffer
    */
@@ -160,19 +170,95 @@ static int
 verify_deposit_signature_forbidden (const struct TALER_MINT_DepositHandle *dh,
                                     json_t *json)
 {
-  struct MAJ_Specification spec[] = {
+  json_t *history;
-    MAJ_spec_end
+  size_t len;
-  };
+  size_t off;
+  struct TALER_Amount total;
 
-  if (GNUNET_OK !=
+  history = json_object_get (json,
-      MAJ_parse_json (json,
+                             "history");
-                      spec))
+  if (NULL == history)
   {
     GNUNET_break_op (0);
     return GNUNET_SYSERR;
   }
+  len = json_array_size (history);
+  if (0 == len)
+  {
+    GNUNET_break_op (0);
+    return GNUNET_SYSERR;
+  }
+  TALER_amount_get_zero (dh->coin_value.currency,
+                         &total);
+  for (off=0;off<len;off++)
+  {
+    json_t *transaction;
+    struct TALER_Amount amount;
+    struct GNUNET_CRYPTO_EccSignaturePurpose *purpose;
+    struct MAJ_Specification spec[] = {
+      MAJ_spec_amount ("amount",
+                       &amount),
+      MAJ_spec_eddsa_signed_purpose ("signature",
+                                     &purpose,
+                                     &dh->depconf.coin_pub.eddsa_pub),
+      MAJ_spec_end
+    };
 
-  GNUNET_break (0); // not implemented
+    transaction = json_array_get (history,
+                                  off);
+    if (GNUNET_OK !=
+        MAJ_parse_json (transaction,
+                        spec))
+    {
+      GNUNET_break_op (0);
+      return GNUNET_SYSERR;
+    }
+    switch (purpose->purpose)
+    {
+    case TALER_SIGNATURE_WALLET_COIN_DEPOSIT:
+      GNUNET_break (0);
+      /* FIXME: check amount! #3516 */
+      break;
+    case TALER_SIGNATURE_WALLET_COIN_MELT:
+      GNUNET_break (0);
+      /* FIXME: check amount! #3516 */
+      break;
+    default:
+      /* signature not supported, new version on server? */
+      GNUNET_break (0);
+      MAJ_parse_free (spec);
+      return GNUNET_SYSERR;
+    }
+    if (GNUNET_OK !=
+        TALER_amount_add (&total,
+                          &total,
+                          &amount))
+    {
+      /* overflow in history already!? inconceivable! */
+      GNUNET_break_op (0);
+      MAJ_parse_free (spec);
+      return GNUNET_SYSERR;
+    }
+    MAJ_parse_free (spec);
+  }
+  if (GNUNET_OK !=
+      TALER_amount_add (&total,
+                        &total,
+                        &dh->amount_with_fee))
+  {
+    /* clearly not OK if our transaction would have caused
+       the overflow... */
+    return GNUNET_OK;
+  }
+
+  if (0 >= TALER_amount_cmp (&total,
+                             &dh->coin_value))
+  {
+    /* transaction should have still fit */
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  /* everything OK, proof of double-spending was provided */
   return GNUNET_OK;
 }
 
@@ -530,7 +616,8 @@ TALER_MINT_deposit (struct TALER_MINT_Handle *mint,
                      &amount_without_fee);
   dh->depconf.coin_pub = *coin_pub;
   dh->depconf.merchant = *merchant_pub;
-
+  dh->amount_with_fee = *amount;
+  dh->coin_value = dki->value;
 
   eh = curl_easy_init ();
   GNUNET_assert (NULL != (dh->json_enc =

src/mint-lib/mint_api_json.c

@@ -200,6 +200,17 @@ parse_json (json_t *root,
       }
       break;
 
+    case MAJ_CMD_EDDSA_SIGNATURE:
+      {
+        /* FIXME: parse the JSON signature
+           and the purpose, then check that the
+           signature is valid and the size field
+           is also correct; if all checks out,
+           return the purpose */
+        GNUNET_break (0); // FIXME: implement! #3516
+      }
+      break;
+
     default:
       GNUNET_break (0);
       return i;
@@ -248,6 +259,9 @@ parse_free (struct MAJ_Specification *spec,
       GNUNET_CRYPTO_rsa_signature_free (*spec[i].details.rsa_signature);
       *spec[i].details.rsa_signature = NULL;
       break;
+    case MAJ_CMD_EDDSA_SIGNATURE:
+      GNUNET_free (*spec[i].details.eddsa_signature.purpose_p);
+      *spec[i].details.eddsa_signature.purpose_p = NULL;
     default:
       GNUNET_break (0);
       break;
@@ -378,4 +392,28 @@ MAJ_spec_rsa_signature (const char *name,
 }
 
 
+/**
+ * Specification for parsing an EdDSA object signature with purpose.
+ * Also validates the signature (!).
+ *
+ * @param name name of the JSON field
+ * @param purpose_p where to store the purpose
+ * @param pub_key public key to use for validation
+ */
+struct MAJ_Specification
+MAJ_spec_eddsa_signed_purpose (const char *name,
+                               struct GNUNET_CRYPTO_EccSignaturePurpose **purpose_p,
+                               const struct GNUNET_CRYPTO_EddsaPublicKey *pub_key)
+{
+  struct MAJ_Specification ret =
+    {
+      .cmd = MAJ_CMD_EDDSA_SIGNATURE,
+      .field = name,
+      .details.eddsa_signature.purpose_p = purpose_p,
+      .details.eddsa_signature.pub_key = pub_key
+    };
+  return ret;
+}
+
+
 /* end of mint_api_json.c */

src/mint-lib/mint_api_json.h

@@ -69,9 +69,9 @@ enum MAJ_Command
   MAJ_CMD_RSA_SIGNATURE,
 
   /**
-   * Parse  at current position.
+   * Parse object with EdDSA signature and purpose at current position.
    */
-  MAJ_CMD_A,
+  MAJ_CMD_EDDSA_SIGNATURE,
 
   /**
    * Parse  at current position.
@@ -159,6 +159,23 @@ struct MAJ_Specification
      */
     struct GNUNET_CRYPTO_rsa_Signature **rsa_signature;
 
+    /**
+     * Details for #MAJ_CMD_EDDSA_SIGNATURE
+     */
+    struct {
+
+      /**
+       * Where to store the purpose.
+       */
+      struct GNUNET_CRYPTO_EccSignaturePurpose **purpose_p;
+
+      /**
+       * Key to verify the signature against.
+       */
+      const struct GNUNET_CRYPTO_EddsaPublicKey *pub_key;
+
+    } eddsa_signature;
+
   } details;
 
 };
@@ -223,6 +240,20 @@ MAJ_spec_amount (const char *name,
                  struct TALER_Amount *amount);
 
 
+/**
+ * Specification for parsing an EdDSA object signature with purpose.
+ * Also validates the signature (!).
+ *
+ * @param name name of the JSON field
+ * @param purpose_p where to store the purpose
+ * @param pub_key public key to use for validation
+ */
+struct MAJ_Specification
+MAJ_spec_eddsa_signed_purpose (const char *name,
+                               struct GNUNET_CRYPTO_EccSignaturePurpose **purpose_p,
+                               const struct GNUNET_CRYPTO_EddsaPublicKey *pub_key);
+
+
 /**
  * Specification for parsing an RSA public key.
  *