c-ares: upgrade library to 1.20.1 (#33711)

This change does following:

* Updates c-ares library to 1.20 to get access to the required change in c-ares library.
* Updates dirty_channel status check logic to conditionally check for status == ARES_EREFUSED without which DestroyChannelOnRefused and CustomResolverValidAfterChannelDestruction test fail after upgrading the c-ares library to 1.20.1.

Risk Level: low
Testing: unit testing

Signed-off-by: deveshkandpal1224 <deveshkandpal1224@gmail.com>

bazel/repository_locations.bzl

@@ -218,12 +218,12 @@ REPOSITORY_LOCATIONS_SPEC = dict(
         project_name = "c-ares",
         project_desc = "C library for asynchronous DNS requests",
         project_url = "https://c-ares.haxx.se/",
-        version = "1.19.1",
-        sha256 = "321700399b72ed0e037d0074c629e7741f6b2ec2dda92956abe3e9671d3e268e",
+        version = "1.20.1",
+        sha256 = "de24a314844cb157909730828560628704f4f896d167dd7da0fa2fb93ea18b10",
         strip_prefix = "c-ares-{version}",
         urls = ["https://github.com/c-ares/c-ares/releases/download/cares-{underscore_version}/c-ares-{version}.tar.gz"],
         use_category = ["dataplane_core", "controlplane"],
-        release_date = "2023-05-22",
+        release_date = "2023-10-08",
         cpe = "cpe:2.3:a:c-ares_project:c-ares:*",
         license = "c-ares",
         license_url = "https://github.com/c-ares/c-ares/blob/cares-{underscore_version}/LICENSE.md",

changelogs/current.yaml

@@ -25,7 +25,11 @@ bug_fixes:
   change: |
     Fix a RELEASE_ASSERT when using :ref:`auto_sni <envoy_v3_api_field_config.core.v3.UpstreamHttpProtocolOptions.auto_sni>`
     if the downstream request ``:authority`` was longer than 255 characters.
-
+- area: cares
+  change: |
+    Upgraded c-ares library to 1.20.1 and added fix to c-ares DNS implementation to additionally check for ``ARES_EREFUSED``,
+    ``ARES_ESERVFAIL``and ``ARES_ENOTIMP`` status. Without this fix, ``DestroyChannelOnRefused`` and
+    ``CustomResolverValidAfterChannelDestruction`` unit test will break.
 
 removed_config_or_runtime:
 # *Normally occurs at the end of the* :ref:`deprecation period <deprecated>`

source/extensions/network/dns_resolver/cares/dns_impl.cc

@@ -194,7 +194,8 @@ void DnsResolverImpl::AddrInfoPendingResolution::onAresGetAddrInfoCallback(
     //
     // The channel cannot be destroyed and reinitialized here because that leads to a c-ares
     // segfault.
-    if (status == ARES_ECONNREFUSED) {
+    if (status == ARES_ECONNREFUSED || status == ARES_EREFUSED || status == ARES_ESERVFAIL ||
+        status == ARES_ENOTIMP) {
       parent_.dirty_channel_ = true;
     }
   }