check range of fetch-quota-param parameters

the 'low', 'high' and 'discount' parameters to 'fetch-quota-param'
are meant to be ratios with values between zero and one, but higher
values can be assigned. this could potentially lead to an assertion
in maybe_adjust_quota().

diff --git a/bin/tests/system/checkconf/bad-fetchparam.conf b/bin/tests/system/checkconf/bad-fetchparam.conf
new file mode 100644 (file)
index 0000000..b416741
--- /dev/null
+++ b/bin/tests/system/checkconf/bad-fetchparam.conf
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0.  If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/* Bad fetch-quota-params */
+options {
+       fetch-quota-params 1 2 3 2;
+};

diff --git a/lib/isccfg/check.c b/lib/isccfg/check.c
index c4ddf1940dc1942b10b282ce4d6fe18152f188b8..464ece61cdd3a7c0c7e908c931f2b74635684df1 100644 (file)
--- a/lib/isccfg/check.c
+++ b/lib/isccfg/check.c
@@ -875,6 +875,61 @@ check_ratelimit(cfg_aclconfctx_t *actx, const cfg_obj_t *voptions,
        return (result);
 }
 
+static isc_result_t
+check_fetchlimit(const cfg_obj_t *voptions, const cfg_obj_t *config,
+                isc_log_t *logctx) {
+       const cfg_obj_t *map = NULL;
+       const cfg_obj_t *options = NULL;
+       const cfg_obj_t *obj = NULL;
+       double low, high, discount;
+
+       if (voptions != NULL) {
+               cfg_map_get(voptions, "fetch-quota-params", &map);
+       }
+       if (config != NULL && map == NULL) {
+               options = NULL;
+               cfg_map_get(config, "options", &options);
+               if (options != NULL) {
+                       cfg_map_get(options, "fetch-quota-params", &map);
+               }
+       }
+       if (map == NULL) {
+               return (ISC_R_SUCCESS);
+       }
+
+       obj = cfg_tuple_get(map, "low");
+       low = (double)cfg_obj_asfixedpoint(obj) / 100.0;
+       if (low < 0.0 || low > 1.0) {
+               cfg_obj_log(obj, logctx, ISC_LOG_ERROR,
+                           "fetch-quota-param low value (%0.1f) "
+                           "out of range",
+                           low);
+               return (ISC_R_RANGE);
+       }
+
+       obj = cfg_tuple_get(map, "high");
+       high = (double)cfg_obj_asfixedpoint(obj) / 100.0;
+       if (high < 0.0 || high > 1.0) {
+               cfg_obj_log(obj, logctx, ISC_LOG_ERROR,
+                           "fetch-quota-param high value (%0.1f) "
+                           "out of range",
+                           high);
+               return (ISC_R_RANGE);
+       }
+
+       obj = cfg_tuple_get(map, "discount");
+       discount = (double)cfg_obj_asfixedpoint(obj) / 100.0;
+       if (discount < 0.0 || discount > 1.0) {
+               cfg_obj_log(obj, logctx, ISC_LOG_ERROR,
+                           "fetch-quota-param discount value (%0.1f) "
+                           "out of range",
+                           discount);
+               return (ISC_R_RANGE);
+       }
+
+       return (ISC_R_SUCCESS);
+}
+
 /*
  * Check allow-recursion and allow-recursion-on acls, and also log a
  * warning if they're inconsistent with the "recursion" option.
@@ -5739,6 +5794,11 @@ check_viewconf(const cfg_obj_t *config, const cfg_obj_t *voptions,
                result = tresult;
        }
 
+       tresult = check_fetchlimit(voptions, config, logctx);
+       if (tresult != ISC_R_SUCCESS) {
+               result = tresult;
+       }
+
        /*
         * Load plugins.
         */