handle (most) TEH_KS_acquire errors

src/exchange/taler-exchange-httpd_deposit.c

@@ -104,7 +104,7 @@ struct DepositContext
    * Value of the coin.
    */
   struct TALER_Amount value;
-  
+
 };
 
 
@@ -133,7 +133,7 @@ deposit_transaction (void *cls,
   struct TALER_EXCHANGEDB_TransactionList *tl;
   struct TALER_Amount spent;
   enum GNUNET_DB_QueryStatus qs;
-  
+
   qs = TEH_plugin->have_deposit (TEH_plugin->cls,
 				 session,
 				 deposit);
@@ -255,6 +255,13 @@ verify_and_execute_deposit (struct MHD_Connection *connection,
 
   /* check denomination */
   mks = TEH_KS_acquire ();
+  if (NULL == mks)
+  {
+    TALER_LOG_ERROR ("Lacking keys to operate\n");
+    return TEH_RESPONSE_reply_internal_error (connection,
+                                              TALER_EC_EXCHANGE_BAD_CONFIGURATION,
+                                              "no keys");
+  }
   dki = TEH_KS_denomination_key_lookup (mks,
                                         &deposit->coin.denom_pub,
 					TEH_KS_DKU_DEPOSIT);
@@ -450,6 +457,14 @@ TEH_DEPOSIT_handler_deposit (struct TEH_RequestHandler *rh,
 
   /* check denomination exists and is valid */
   key_state = TEH_KS_acquire ();
+  if (NULL == key_state)
+  {
+    TALER_LOG_ERROR ("Lacking keys to operate\n");
+    GNUNET_JSON_parse_free (spec);
+    return TEH_RESPONSE_reply_internal_error (connection,
+                                              TALER_EC_EXCHANGE_BAD_CONFIGURATION,
+                                              "no keys");
+  }
   dki = TEH_KS_denomination_key_lookup (key_state,
                                         &deposit.coin.denom_pub,
 					TEH_KS_DKU_DEPOSIT);

src/exchange/taler-exchange-httpd_keystate.c

@@ -1571,7 +1571,7 @@ TEH_KS_release_ (const char *location,
  * to #TEH_KS_release() must be made.
  *
  * @param location name of the function in which the lock is acquired
- * @return the key state
+ * @return the key state, NULL on error (usually pretty fatal)
  */
 struct TEH_KS_StateHandle *
 TEH_KS_acquire_ (const char *location)
@@ -1837,6 +1837,11 @@ read_again:
 /**
  * Sign the message in @a purpose with the exchange's signing key.
  *
+ * FIXME:
+ * - Change API to return status code and do not assert on TEH_KS_acquire()
+ *   failures, instead allow caller to handle it (i.e. by returning
+ *   #TALER_EC_EXCHANGE_BAD_CONFIGURATION to application).
+ *
  * @param purpose the message to sign
  * @param[out] pub set to the current public signing key of the exchange
  * @param[out] sig signature over purpose using current signing key
@@ -1850,6 +1855,9 @@ TEH_KS_sign (const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose,
   struct TEH_KS_StateHandle *key_state;
 
   key_state = TEH_KS_acquire ();
+  GNUNET_assert (NULL != key_state); /* This *can* happen if the exchange's keys are
+                                        not properly maintained, but in this case we
+                                        simply have no good way forward. */
   *pub = key_state->current_sign_key_issue.issue.signkey_pub;
   GNUNET_assert (GNUNET_OK ==
                  GNUNET_CRYPTO_eddsa_sign (&key_state->current_sign_key_issue.signkey_priv.eddsa_priv,
@@ -1930,6 +1938,13 @@ TEH_KS_handler_keys (struct TEH_RequestHandler *rh,
     last_issue_date.abs_value_us = 0LLU;
   }
   key_state = TEH_KS_acquire ();
+  if (NULL == key_state)
+  {
+    TALER_LOG_ERROR ("Lacking keys to operate\n");
+    return TEH_RESPONSE_reply_internal_error (connection,
+                                              TALER_EC_EXCHANGE_BAD_CONFIGURATION,
+                                              "no keys");
+  }
   krd = bsearch (&last_issue_date,
                  key_state->krd_array,
                  key_state->krd_array_length,

src/exchange/taler-exchange-httpd_keystate.h

@@ -42,7 +42,7 @@ struct TEH_KS_StateHandle;
  * to #TEH_KS_release() must be made.
  *
  * @param location name of the function in which the lock is acquired
- * @return the key state
+ * @return the key state, NULL on error (usually pretty fatal)
  */
 struct TEH_KS_StateHandle *
 TEH_KS_acquire_ (const char *location);

src/exchange/taler-exchange-httpd_payback.c

@@ -312,6 +312,13 @@ verify_and_execute_payback (struct MHD_Connection *connection,
 
   /* check denomination exists and is in payback mode */
   key_state = TEH_KS_acquire ();
+  if (NULL == key_state)
+  {
+    TALER_LOG_ERROR ("Lacking keys to operate\n");
+    return TEH_RESPONSE_reply_internal_error (connection,
+                                              TALER_EC_EXCHANGE_BAD_CONFIGURATION,
+                                              "no keys");
+  }
   dki = TEH_KS_denomination_key_lookup (key_state,
                                         &coin->denom_pub,
 					TEH_KS_DKU_PAYBACK);

src/exchange/taler-exchange-httpd_refresh_melt.c

@@ -163,7 +163,7 @@ struct RefreshMeltContext
   /**
    * Information about the denomination key of the coin being
    * melted.
-   */ 
+   */
   struct TALER_EXCHANGEDB_DenominationKeyIssueInformation *dki;
 
   /**
@@ -184,7 +184,7 @@ struct RefreshMeltContext
 
   /**
    * Set to the session hash once the @e hash_context has finished.
-   */ 
+   */
   struct GNUNET_HashCode session_hash;
 
   /**
@@ -220,7 +220,7 @@ struct RefreshMeltContext
  * @param[out] mhd_ret status code to return to MHD on hard error
  * @return transaction status code
  */
-static enum GNUNET_DB_QueryStatus 
+static enum GNUNET_DB_QueryStatus
 refresh_check_melt (struct MHD_Connection *connection,
                     struct TALER_EXCHANGEDB_Session *session,
 		    struct RefreshMeltContext *rmc,
@@ -416,7 +416,7 @@ refresh_melt_prepare (struct MHD_Connection *connection,
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "/refresh/melt request for session %s\n",
               GNUNET_h2s (&rmc->session_hash));
-  
+
   GNUNET_assert (GNUNET_OK ==
                  TALER_amount_get_zero (TEH_exchange_currency_string,
                                         &total_cost));
@@ -700,7 +700,7 @@ handle_refresh_melt_json (struct MHD_Connection *connection,
                                      buf_size);
     GNUNET_free (buf);
   }
-  
+
   /* decode JSON data on coin to melt and check that this is a
      valid coin */
   {
@@ -767,6 +767,13 @@ handle_refresh_melt_json (struct MHD_Connection *connection,
   rmc.hash_context = NULL;
 
   rmc.key_state = TEH_KS_acquire ();
+  if (NULL == rmc.key_state)
+  {
+    TALER_LOG_ERROR ("Lacking keys to operate\n");
+    return TEH_RESPONSE_reply_internal_error (connection,
+                                              TALER_EC_EXCHANGE_BAD_CONFIGURATION,
+                                              "no keys");
+  }
   rmc.dki = TEH_KS_denomination_key_lookup (rmc.key_state,
 					    &rmc.coin_melt_details.coin_info.denom_pub,
 					    TEH_KS_DKU_DEPOSIT);
@@ -804,7 +811,7 @@ handle_refresh_melt_json (struct MHD_Connection *connection,
 						TALER_EC_REFRESH_MELT_AMOUNT_INSUFFICIENT,
 						"melt amount smaller than melting fee");
     }
-    
+
     if (GNUNET_OK !=
 	GNUNET_CRYPTO_eddsa_verify (TALER_SIGNATURE_WALLET_COIN_MELT,
 				    &body.purpose,
@@ -818,7 +825,7 @@ handle_refresh_melt_json (struct MHD_Connection *connection,
 						   "confirm_sig");
     }
   }
-    
+
   /* prepare commit */
   if (GNUNET_OK !=
       refresh_melt_prepare (connection,

src/exchange/taler-exchange-httpd_refresh_reveal.c

@@ -531,7 +531,7 @@ refresh_reveal_transaction (void *cls,
   for (unsigned int i=0;i<TALER_CNC_KAPPA;i++)
   {
     int res;
-    
+
     if (i == rc->refresh_session.noreveal_index)
     {
       off = 1;
@@ -542,7 +542,7 @@ refresh_reveal_transaction (void *cls,
 						 rc->refresh_session.num_newcoins,
 						 rc->commit_coins);
       if (0 >= qs)
-      {	
+      {
 	cleanup_rc (rc);
         GNUNET_CRYPTO_hash_context_abort (hash_context);
 	if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
@@ -596,7 +596,7 @@ refresh_reveal_transaction (void *cls,
     cleanup_rc (rc);
     return GNUNET_DB_STATUS_HARD_ERROR;
   }
-  
+
   /* Client request OK, sign coins */
   rc->ev_sigs = GNUNET_new_array (rc->refresh_session.num_newcoins,
 				  struct TALER_DenominationSignature);
@@ -604,6 +604,12 @@ refresh_reveal_transaction (void *cls,
     struct TEH_KS_StateHandle *key_state;
 
     key_state = TEH_KS_acquire ();
+    if (NULL == key_state)
+    {
+      TALER_LOG_ERROR ("Lacking keys to operate\n");
+      cleanup_rc (rc);
+      return GNUNET_DB_STATUS_HARD_ERROR;
+    }
     for (unsigned int j=0;j<rc->refresh_session.num_newcoins;j++)
     {
       qs = refresh_exchange_coin (connection,

src/exchange/taler-exchange-httpd_refund.c

@@ -241,7 +241,7 @@ refund_transaction (void *cls,
                                             tl);
     *mhd_ret = TEH_RESPONSE_reply_transaction_unknown (connection,
 						       TALER_EC_REFUND_DEPOSIT_NOT_FOUND);
-    return GNUNET_DB_STATUS_HARD_ERROR;    
+    return GNUNET_DB_STATUS_HARD_ERROR;
   }
   /* handle if conflicting refund found */
   if (GNUNET_SYSERR == refund_found)
@@ -250,7 +250,7 @@ refund_transaction (void *cls,
 				      tl);
     TEH_plugin->free_coin_transaction_list (TEH_plugin->cls,
                                             tl);
-    return GNUNET_DB_STATUS_HARD_ERROR; 
+    return GNUNET_DB_STATUS_HARD_ERROR;
   }
   /* handle if identical refund found */
   if (GNUNET_YES == refund_found)
@@ -297,7 +297,7 @@ refund_transaction (void *cls,
   }
   if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
     return qs; /* go and retry */
-  
+
   if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT == qs)
   {
     /* money was already transferred to merchant, can no longer refund */
@@ -325,6 +325,16 @@ refund_transaction (void *cls,
   // FIXME: do this outside of transaction function?
   /* Check refund fee matches fee of denomination key! */
   mks = TEH_KS_acquire ();
+  if (NULL == mks)
+  {
+    TALER_LOG_ERROR ("Lacking keys to operate\n");
+    TEH_plugin->free_coin_transaction_list (TEH_plugin->cls,
+                                            tl);
+    *mhd_ret = TEH_RESPONSE_reply_internal_error (connection,
+                                                  TALER_EC_EXCHANGE_BAD_CONFIGURATION,
+                                                  "no keys");
+    return GNUNET_DB_STATUS_HARD_ERROR;
+  }
   dki = TEH_KS_denomination_key_lookup (mks,
                                         &dep->coin.denom_pub,
 					TEH_KS_DKU_DEPOSIT);

src/exchange/taler-exchange-httpd_reserve_withdraw.c

@@ -432,6 +432,14 @@ TEH_RESERVE_handler_reserve_withdraw (struct TEH_RequestHandler *rh,
   if (GNUNET_OK != res)
     return (GNUNET_SYSERR == res) ? MHD_NO : MHD_YES;
   wc.key_state = TEH_KS_acquire ();
+  if (NULL == wc.key_state)
+  {
+    TALER_LOG_ERROR ("Lacking keys to operate\n");
+    GNUNET_JSON_parse_free (spec);
+    return TEH_RESPONSE_reply_internal_error (connection,
+                                              TALER_EC_EXCHANGE_BAD_CONFIGURATION,
+                                              "no keys");
+  }
   wc.dki = TEH_KS_denomination_key_lookup (wc.key_state,
 					   &wc.denomination_pub,
 					   TEH_KS_DKU_WITHDRAW);

src/include/taler_error_codes.h

@@ -53,6 +53,11 @@ enum TALER_ErrorCode
    */
   TALER_EC_NOT_IMPLEMENTED = 3,
 
+  /**
+   * Exchange is badly configured and thus cannot operate.
+   */
+  TALER_EC_EXCHANGE_BAD_CONFIGURATION = 4,
+
   /* ********** generic error codes ************* */
 
   /**
@@ -906,7 +911,7 @@ enum TALER_ErrorCode
    * MHD_HTTP_BAD_REQUEST.
    */
   TALER_EC_KEYS_HAVE_NOT_NUMERIC = 1900,
-  
+
 
   /* *********** Merchant backend error codes ********* */
 
@@ -1264,7 +1269,7 @@ enum TALER_ErrorCode
   /**
    * The exchange charged a different wire fee than what it
    * originally advertised, and it is higher.  The response
-   * is provied with an HTTP status of 
+   * is provied with an HTTP status of
    * MHD_HTTP_INTERNAL_SERVER_ERROR (FIXME: bad choice!).
    */
   TALER_EC_TRACK_TRANSFER_JSON_BAD_WIRE_FEE = 2410,