add signing/verifying functions for global fees

src/include/taler_crypto_lib.h

@@ -3270,6 +3270,43 @@ TALER_exchange_offline_wire_fee_verify (
   const struct TALER_MasterSignatureP *master_sig);
 
 
+/**
+ * Create global fees signature.
+ *
+ * @param start_time when do the fees start to apply
+ * @param end_time when do the fees start to apply
+ * @param fees the global fees
+ * @param master_priv private key to sign with
+ * @param[out] master_sig where to write the signature
+ */
+void
+TALER_exchange_offline_global_fee_sign (
+  struct GNUNET_TIME_Timestamp start_time,
+  struct GNUNET_TIME_Timestamp end_time,
+  const struct TALER_GlobalFeeSet *fees,
+  const struct TALER_MasterPrivateKeyP *master_priv,
+  struct TALER_MasterSignatureP *master_sig);
+
+
+/**
+ * Verify global fees signature.
+ *
+ * @param start_time when do the fees start to apply
+ * @param end_time when do the fees start to apply
+ * @param fees the global fees
+ * @param master_pub public key to verify against
+ * @param master_sig the signature the signature
+ * @return #GNUNET_OK if the signature is valid
+ */
+enum GNUNET_GenericReturnValue
+TALER_exchange_offline_global_fee_verify (
+  struct GNUNET_TIME_Timestamp start_time,
+  struct GNUNET_TIME_Timestamp end_time,
+  const struct TALER_GlobalFeeSet *fees,
+  const struct TALER_MasterPublicKeyP *master_pub,
+  const struct TALER_MasterSignatureP *master_sig);
+
+
 /**
  * Create wire account addition signature.
  *

src/include/taler_signatures.h

@@ -56,6 +56,12 @@
  */
 #define TALER_SIGNATURE_MASTER_ADD_WIRE 1021
 
+/**
+ * Signature over global set of fees charged by the
+ * exchange.
+ */
+#define TALER_SIGNATURE_MASTER_GLOBAL_FEES 1022
+
 /**
  * Remove payto URI from the list of our wire methods.
  */
@@ -1250,6 +1256,36 @@ struct TALER_MasterWireFeePS
 };
 
 
+/**
+ * Global fees charged by the exchange independent of
+ * denomination or wire method.
+ */
+struct TALER_MasterGlobalFeePS
+{
+
+  /**
+   * Purpose is #TALER_SIGNATURE_MASTER_GLOBAL_FEES.
+   */
+  struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
+
+  /**
+   * Start date when the fee goes into effect.
+   */
+  struct GNUNET_TIME_TimestampNBO start_date;
+
+  /**
+   * End date when the fee stops being in effect (exclusive)
+   */
+  struct GNUNET_TIME_TimestampNBO end_date;
+
+  /**
+   * Fee charged to the merchant per wire transfer.
+   */
+  struct TALER_GlobalFeeSetNBOP fees;
+
+};
+
+
 /**
  * @brief Message confirming that a denomination key was revoked.
  */

src/util/offline_signatures.c

@@ -472,6 +472,54 @@ TALER_exchange_offline_wire_fee_verify (
 }
 
 
+void
+TALER_exchange_offline_global_fee_sign (
+  struct GNUNET_TIME_Timestamp start_time,
+  struct GNUNET_TIME_Timestamp end_time,
+  const struct TALER_GlobalFeeSet *fees,
+  const struct TALER_MasterPrivateKeyP *master_priv,
+  struct TALER_MasterSignatureP *master_sig)
+{
+  struct TALER_MasterGlobalFeePS kv = {
+    .purpose.purpose = htonl (TALER_SIGNATURE_MASTER_GLOBAL_FEES),
+    .purpose.size = htonl (sizeof (kv)),
+    .start_date = GNUNET_TIME_timestamp_hton (start_time),
+    .end_date = GNUNET_TIME_timestamp_hton (end_time),
+  };
+
+  TALER_global_fee_set_hton (&kv.fees,
+                             fees);
+  GNUNET_CRYPTO_eddsa_sign (&master_priv->eddsa_priv,
+                            &kv,
+                            &master_sig->eddsa_signature);
+}
+
+
+enum GNUNET_GenericReturnValue
+TALER_exchange_offline_global_fee_verify (
+  struct GNUNET_TIME_Timestamp start_time,
+  struct GNUNET_TIME_Timestamp end_time,
+  const struct TALER_GlobalFeeSet *fees,
+  const struct TALER_MasterPublicKeyP *master_pub,
+  const struct TALER_MasterSignatureP *master_sig)
+{
+  struct TALER_MasterGlobalFeePS wf = {
+    .purpose.purpose = htonl (TALER_SIGNATURE_MASTER_GLOBAL_FEES),
+    .purpose.size = htonl (sizeof (wf)),
+    .start_date = GNUNET_TIME_timestamp_hton (start_time),
+    .end_date = GNUNET_TIME_timestamp_hton (end_time)
+  };
+
+  TALER_global_fee_set_hton (&wf.fees,
+                             fees);
+  return
+    GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_MASTER_GLOBAL_FEES,
+                                &wf,
+                                &master_sig->eddsa_signature,
+                                &master_pub->eddsa_pub);
+}
+
+
 void
 TALER_exchange_offline_extension_config_hash_sign (
   const struct TALER_ExtensionConfigHashP *h_config,