mobile: Add EngineBuilder::setDnsNumRetries (envoyproxy#35906)

This PR adds a configuration to set the number of DNS retries. If not
specified, the DNS resolver will indefinitely retry until it succeeds or
the DNS query times out.

Risk Level: low (a new feature)
Testing: unit tests
Docs Changes: n/a
Release Notes: n/a
Platform Specific Features: mobile

---------

Signed-off-by: Fredy Wijaya <[email protected]>

mobile/library/cc/engine_builder.cc

@@ -113,6 +113,11 @@ EngineBuilder& EngineBuilder::addDnsQueryTimeoutSeconds(int dns_query_timeout_se
   return *this;
 }
 
+EngineBuilder& EngineBuilder::setDnsNumRetries(uint32_t dns_num_retries) {
+  dns_num_retries_ = dns_num_retries;
+  return *this;
+}
+
 EngineBuilder& EngineBuilder::addDnsPreresolveHostnames(const std::vector<std::string>& hostnames) {
   // Add a default port of 443 for all hosts. We'll eventually change this API so it takes a single
   // {host, pair} and it can be called multiple times.
@@ -488,6 +493,9 @@ std::unique_ptr<envoy::config::bootstrap::v3::Bootstrap> EngineBuilder::generate
   } else {
     envoy::extensions::network::dns_resolver::getaddrinfo::v3::GetAddrInfoDnsResolverConfig
         resolver_config;
+    if (dns_num_retries_.has_value()) {
+      resolver_config.mutable_num_retries()->set_value(*dns_num_retries_);
+    }
     dns_cache_config->mutable_typed_dns_resolver_config()->set_name(
         "envoy.network.dns_resolver.getaddrinfo");
     dns_cache_config->mutable_typed_dns_resolver_config()->mutable_typed_config()->PackFrom(

mobile/library/cc/engine_builder.h

@@ -41,6 +41,7 @@ class EngineBuilder {
   EngineBuilder& addDnsFailureRefreshSeconds(int base, int max);
   EngineBuilder& addDnsQueryTimeoutSeconds(int dns_query_timeout_seconds);
   EngineBuilder& addDnsMinRefreshSeconds(int dns_min_refresh_seconds);
+  EngineBuilder& setDnsNumRetries(uint32_t dns_num_retries);
   EngineBuilder& addMaxConnectionsPerHost(int max_connections_per_host);
   EngineBuilder& addH2ConnectionKeepaliveIdleIntervalMilliseconds(
       int h2_connection_keepalive_idle_interval_milliseconds);
@@ -138,6 +139,7 @@ class EngineBuilder {
   int dns_failure_refresh_seconds_base_ = 2;
   int dns_failure_refresh_seconds_max_ = 10;
   int dns_query_timeout_seconds_ = 5;
+  absl::optional<uint32_t> dns_num_retries_ = absl::nullopt;
   int h2_connection_keepalive_idle_interval_milliseconds_ = 100000000;
   int h2_connection_keepalive_timeout_seconds_ = 10;
   std::string app_version_ = "unspecified";

mobile/library/java/io/envoyproxy/envoymobile/engine/EnvoyConfiguration.java

@@ -34,6 +34,7 @@ public enum TrustChainVerification {
   public final List<String> dnsPreresolveHostnames;
   public final Boolean enableDNSCache;
   public final Integer dnsCacheSaveIntervalSeconds;
+  public final int dnsNumRetries;
   public final Boolean enableDrainPostDnsRefresh;
   public final Boolean enableHttp3;
   public final Boolean useCares;
@@ -85,6 +86,8 @@ public enum TrustChainVerification {
    * @param enableDNSCache                                whether to enable DNS cache.
    * @param dnsCacheSaveIntervalSeconds                   the interval at which to save results to
    *     the configured key value store.
+   * @param dnsNumRetries                                 the number of retries before the DNS
+   *     resolver gives up
    * @param enableDrainPostDnsRefresh                     whether to drain connections after soft
    *     DNS refresh.
    * @param enableHttp3                                   whether to enable experimental support for
@@ -130,8 +133,8 @@ public EnvoyConfiguration(
       int connectTimeoutSeconds, int dnsRefreshSeconds, int dnsFailureRefreshSecondsBase,
       int dnsFailureRefreshSecondsMax, int dnsQueryTimeoutSeconds, int dnsMinRefreshSeconds,
       List<String> dnsPreresolveHostnames, boolean enableDNSCache, int dnsCacheSaveIntervalSeconds,
-      boolean enableDrainPostDnsRefresh, boolean enableHttp3, boolean useCares, boolean useGro,
-      String http3ConnectionOptions, String http3ClientConnectionOptions,
+      int dnsNumRetries, boolean enableDrainPostDnsRefresh, boolean enableHttp3, boolean useCares,
+      boolean useGro, String http3ConnectionOptions, String http3ClientConnectionOptions,
       Map<String, Integer> quicHints, List<String> quicCanonicalSuffixes,
       boolean enableGzipDecompression, boolean enableBrotliDecompression,
       boolean enablePortMigration, boolean enableSocketTagging, boolean enableInterfaceBinding,
@@ -153,6 +156,7 @@ public EnvoyConfiguration(
     this.dnsPreresolveHostnames = dnsPreresolveHostnames;
     this.enableDNSCache = enableDNSCache;
     this.dnsCacheSaveIntervalSeconds = dnsCacheSaveIntervalSeconds;
+    this.dnsNumRetries = dnsNumRetries;
     this.enableDrainPostDnsRefresh = enableDrainPostDnsRefresh;
     this.enableHttp3 = enableHttp3;
     this.useCares = useCares;
@@ -215,13 +219,14 @@ public long createBootstrap() {
     return JniLibrary.createBootstrap(
         connectTimeoutSeconds, dnsRefreshSeconds, dnsFailureRefreshSecondsBase,
         dnsFailureRefreshSecondsMax, dnsQueryTimeoutSeconds, dnsMinRefreshSeconds, dnsPreresolve,
-        enableDNSCache, dnsCacheSaveIntervalSeconds, enableDrainPostDnsRefresh, enableHttp3,
-        useCares, useGro, http3ConnectionOptions, http3ClientConnectionOptions, quicHints,
-        quicSuffixes, enableGzipDecompression, enableBrotliDecompression, enablePortMigration,
-        enableSocketTagging, enableInterfaceBinding, h2ConnectionKeepaliveIdleIntervalMilliseconds,
-        h2ConnectionKeepaliveTimeoutSeconds, maxConnectionsPerHost, streamIdleTimeoutSeconds,
-        perTryIdleTimeoutSeconds, appVersion, appId, enforceTrustChainVerification, filterChain,
-        enablePlatformCertificatesValidation, upstreamTlsSni, runtimeGuards);
+        enableDNSCache, dnsCacheSaveIntervalSeconds, dnsNumRetries, enableDrainPostDnsRefresh,
+        enableHttp3, useCares, useGro, http3ConnectionOptions, http3ClientConnectionOptions,
+        quicHints, quicSuffixes, enableGzipDecompression, enableBrotliDecompression,
+        enablePortMigration, enableSocketTagging, enableInterfaceBinding,
+        h2ConnectionKeepaliveIdleIntervalMilliseconds, h2ConnectionKeepaliveTimeoutSeconds,
+        maxConnectionsPerHost, streamIdleTimeoutSeconds, perTryIdleTimeoutSeconds, appVersion,
+        appId, enforceTrustChainVerification, filterChain, enablePlatformCertificatesValidation,
+        upstreamTlsSni, runtimeGuards);
   }
 
   static class ConfigurationException extends RuntimeException {

mobile/library/java/io/envoyproxy/envoymobile/engine/JniLibrary.java

@@ -296,9 +296,9 @@ public static native long createBootstrap(
       long connectTimeoutSeconds, long dnsRefreshSeconds, long dnsFailureRefreshSecondsBase,
       long dnsFailureRefreshSecondsMax, long dnsQueryTimeoutSeconds, long dnsMinRefreshSeconds,
       byte[][] dnsPreresolveHostnames, boolean enableDNSCache, long dnsCacheSaveIntervalSeconds,
-      boolean enableDrainPostDnsRefresh, boolean enableHttp3, boolean useCares, boolean useGro,
-      String http3ConnectionOptions, String http3ClientConnectionOptions, byte[][] quicHints,
-      byte[][] quicCanonicalSuffixes, boolean enableGzipDecompression,
+      int dnsNumRetries, boolean enableDrainPostDnsRefresh, boolean enableHttp3, boolean useCares,
+      boolean useGro, String http3ConnectionOptions, String http3ClientConnectionOptions,
+      byte[][] quicHints, byte[][] quicCanonicalSuffixes, boolean enableGzipDecompression,
       boolean enableBrotliDecompression, boolean enablePortMigration, boolean enableSocketTagging,
       boolean enableInterfaceBinding, long h2ConnectionKeepaliveIdleIntervalMilliseconds,
       long h2ConnectionKeepaliveTimeoutSeconds, long maxConnectionsPerHost,

mobile/library/java/org/chromium/net/impl/NativeCronvoyEngineBuilderImpl.java

@@ -23,6 +23,8 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
+
 import org.chromium.net.ExperimentalCronetEngine;
 import org.chromium.net.ICronetEngineBuilder;
 import com.google.protobuf.Any;
@@ -44,6 +46,7 @@ public class NativeCronvoyEngineBuilderImpl extends CronvoyEngineBuilderImpl {
   private final List<String> mDnsPreresolveHostnames = Collections.emptyList();
   private final boolean mEnableDNSCache = false;
   private final int mDnsCacheSaveIntervalSeconds = 1;
+  private Optional<Integer> mDnsNumRetries = Optional.empty();
   private final List<String> mDnsFallbackNameservers = Collections.emptyList();
   private final boolean mEnableDnsFilterUnroutableFamilies = true;
   private boolean mUseCares = false;
@@ -143,6 +146,18 @@ public NativeCronvoyEngineBuilderImpl setMinDnsRefreshSeconds(int minRefreshSeco
     return this;
   }
 
+  /**
+   * Specifies the number of retries before the resolver gives up. If not specified, the resolver
+   * will retry indefinitely until it succeeds or the DNS query times out.
+   *
+   * @param dnsNumRetries the number of retries
+   * @return this builder
+   */
+  public NativeCronvoyEngineBuilderImpl setDnsNumRetries(int dnsNumRetries) {
+    mDnsNumRetries = Optional.of(dnsNumRetries);
+    return this;
+  }
+
   /**
    * Set the stream idle timeout, in seconds, which is defined as the period in which there are no
    * active requests. When the idle timeout is reached, the connection is closed.
@@ -250,10 +265,10 @@ private EnvoyConfiguration createEnvoyConfiguration() {
         mConnectTimeoutSeconds, mDnsRefreshSeconds, mDnsFailureRefreshSecondsBase,
         mDnsFailureRefreshSecondsMax, mDnsQueryTimeoutSeconds, mDnsMinRefreshSeconds,
         mDnsPreresolveHostnames, mEnableDNSCache, mDnsCacheSaveIntervalSeconds,
-        mEnableDrainPostDnsRefresh, quicEnabled(), mUseCares, mUseGro, quicConnectionOptions(),
-        quicClientConnectionOptions(), quicHints(), quicCanonicalSuffixes(),
-        mEnableGzipDecompression, brotliEnabled(), portMigrationEnabled(), mEnableSocketTag,
-        mEnableInterfaceBinding, mH2ConnectionKeepaliveIdleIntervalMilliseconds,
+        mDnsNumRetries.orElse(-1), mEnableDrainPostDnsRefresh, quicEnabled(), mUseCares, mUseGro,
+        quicConnectionOptions(), quicClientConnectionOptions(), quicHints(),
+        quicCanonicalSuffixes(), mEnableGzipDecompression, brotliEnabled(), portMigrationEnabled(),
+        mEnableSocketTag, mEnableInterfaceBinding, mH2ConnectionKeepaliveIdleIntervalMilliseconds,
         mH2ConnectionKeepaliveTimeoutSeconds, mMaxConnectionsPerHost, mStreamIdleTimeoutSeconds,
         mPerTryIdleTimeoutSeconds, mAppVersion, mAppId, mTrustChainVerification, nativeFilterChain,
         platformFilterChain, stringAccessors, keyValueStores, mRuntimeGuards,

mobile/library/jni/jni_impl.cc

@@ -1195,12 +1195,13 @@ void configureBuilder(Envoy::JNI::JniHelper& jni_helper, jlong connect_timeout_s
                       jlong dns_failure_refresh_seconds_max, jlong dns_query_timeout_seconds,
                       jlong dns_min_refresh_seconds, jobjectArray dns_preresolve_hostnames,
                       jboolean enable_dns_cache, jlong dns_cache_save_interval_seconds,
-                      jboolean enable_drain_post_dns_refresh, jboolean enable_http3,
-                      jboolean use_cares, jboolean use_gro, jstring http3_connection_options,
-                      jstring http3_client_connection_options, jobjectArray quic_hints,
-                      jobjectArray quic_canonical_suffixes, jboolean enable_gzip_decompression,
-                      jboolean enable_brotli_decompression, jboolean enable_port_migration,
-                      jboolean enable_socket_tagging, jboolean enable_interface_binding,
+                      jint dns_num_retries, jboolean enable_drain_post_dns_refresh,
+                      jboolean enable_http3, jboolean use_cares, jboolean use_gro,
+                      jstring http3_connection_options, jstring http3_client_connection_options,
+                      jobjectArray quic_hints, jobjectArray quic_canonical_suffixes,
+                      jboolean enable_gzip_decompression, jboolean enable_brotli_decompression,
+                      jboolean enable_port_migration, jboolean enable_socket_tagging,
+                      jboolean enable_interface_binding,
                       jlong h2_connection_keepalive_idle_interval_milliseconds,
                       jlong h2_connection_keepalive_timeout_seconds, jlong max_connections_per_host,
                       jlong stream_idle_timeout_seconds, jlong per_try_idle_timeout_seconds,
@@ -1215,6 +1216,9 @@ void configureBuilder(Envoy::JNI::JniHelper& jni_helper, jlong connect_timeout_s
   builder.addDnsQueryTimeoutSeconds((dns_query_timeout_seconds));
   builder.addDnsMinRefreshSeconds((dns_min_refresh_seconds));
   builder.enableDnsCache(enable_dns_cache == JNI_TRUE, dns_cache_save_interval_seconds);
+  if (dns_num_retries >= 0) {
+    builder.setDnsNumRetries(dns_num_retries);
+  }
   builder.addMaxConnectionsPerHost((max_connections_per_host));
   builder.addH2ConnectionKeepaliveIdleIntervalMilliseconds(
       (h2_connection_keepalive_idle_interval_milliseconds));
@@ -1288,13 +1292,13 @@ extern "C" JNIEXPORT jlong JNICALL Java_io_envoyproxy_envoymobile_engine_JniLibr
     jlong dns_failure_refresh_seconds_base, jlong dns_failure_refresh_seconds_max,
     jlong dns_query_timeout_seconds, jlong dns_min_refresh_seconds,
     jobjectArray dns_preresolve_hostnames, jboolean enable_dns_cache,
-    jlong dns_cache_save_interval_seconds, jboolean enable_drain_post_dns_refresh,
-    jboolean enable_http3, jboolean use_cares, jboolean use_gro, jstring http3_connection_options,
-    jstring http3_client_connection_options, jobjectArray quic_hints,
-    jobjectArray quic_canonical_suffixes, jboolean enable_gzip_decompression,
-    jboolean enable_brotli_decompression, jboolean enable_port_migration,
-    jboolean enable_socket_tagging, jboolean enable_interface_binding,
-    jlong h2_connection_keepalive_idle_interval_milliseconds,
+    jlong dns_cache_save_interval_seconds, jint dns_num_retries,
+    jboolean enable_drain_post_dns_refresh, jboolean enable_http3, jboolean use_cares,
+    jboolean use_gro, jstring http3_connection_options, jstring http3_client_connection_options,
+    jobjectArray quic_hints, jobjectArray quic_canonical_suffixes,
+    jboolean enable_gzip_decompression, jboolean enable_brotli_decompression,
+    jboolean enable_port_migration, jboolean enable_socket_tagging,
+    jboolean enable_interface_binding, jlong h2_connection_keepalive_idle_interval_milliseconds,
     jlong h2_connection_keepalive_timeout_seconds, jlong max_connections_per_host,
     jlong stream_idle_timeout_seconds, jlong per_try_idle_timeout_seconds, jstring app_version,
     jstring app_id, jboolean trust_chain_verification, jobjectArray filter_chain,
@@ -1306,7 +1310,7 @@ extern "C" JNIEXPORT jlong JNICALL Java_io_envoyproxy_envoymobile_engine_JniLibr
   configureBuilder(
       jni_helper, connect_timeout_seconds, dns_refresh_seconds, dns_failure_refresh_seconds_base,
       dns_failure_refresh_seconds_max, dns_query_timeout_seconds, dns_min_refresh_seconds,
-      dns_preresolve_hostnames, enable_dns_cache, dns_cache_save_interval_seconds,
+      dns_preresolve_hostnames, enable_dns_cache, dns_cache_save_interval_seconds, dns_num_retries,
       enable_drain_post_dns_refresh, enable_http3, use_cares, use_gro, http3_connection_options,
       http3_client_connection_options, quic_hints, quic_canonical_suffixes,
       enable_gzip_decompression, enable_brotli_decompression, enable_port_migration,

mobile/library/kotlin/io/envoyproxy/envoymobile/EngineBuilder.kt

@@ -34,6 +34,8 @@ open class EngineBuilder() {
   private var dnsPreresolveHostnames = listOf<String>()
   private var enableDNSCache = false
   private var dnsCacheSaveIntervalSeconds = 1
+  // null means the DNS resolver will try indefinitely until it succeeds.
+  private var dnsNumRetries: Int? = null
   private var enableDrainPostDnsRefresh = false
   internal var enableHttp3 = true
   internal var useCares = false
@@ -142,6 +144,18 @@ open class EngineBuilder() {
     return this
   }
 
+  /**
+   * Specifies the number of retries before the resolver gives up. If not specified, the resolver
+   * will retry indefinitely until it succeeds or the DNS query times out.
+   *
+   * @param dnsNumRetries the number of retries
+   * @return this builder
+   */
+  fun setDnsNumRetries(dnsNumRetries: Int): EngineBuilder {
+    this.dnsNumRetries = dnsNumRetries
+    return this
+  }
+
   /**
    * Specify whether to drain connections after the resolution of a soft DNS refresh. A refresh may
    * be triggered directly via the Engine API, or as a result of a network status update provided by
@@ -526,6 +540,7 @@ open class EngineBuilder() {
         dnsPreresolveHostnames,
         enableDNSCache,
         dnsCacheSaveIntervalSeconds,
+        dnsNumRetries ?: -1,
         enableDrainPostDnsRefresh,
         enableHttp3,
         useCares,

mobile/library/objective-c/EnvoyConfiguration.h

@@ -22,6 +22,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nonatomic, assign) UInt32 dnsRefreshSeconds;
 @property (nonatomic, assign) BOOL enableDNSCache;
 @property (nonatomic, assign) UInt32 dnsCacheSaveIntervalSeconds;
+@property (nonatomic, assign) NSInteger dnsNumRetries;
 @property (nonatomic, assign) BOOL enableHttp3;
 @property (nonatomic, strong) NSDictionary<NSString *, NSNumber *> *quicHints;
 @property (nonatomic, strong) NSArray<NSString *> *quicCanonicalSuffixes;
@@ -60,6 +61,7 @@ NS_ASSUME_NONNULL_BEGIN
                            dnsPreresolveHostnames:(NSArray<NSString *> *)dnsPreresolveHostnames
                                    enableDNSCache:(BOOL)enableDNSCache
                       dnsCacheSaveIntervalSeconds:(UInt32)dnsCacheSaveIntervalSeconds
+                                    dnsNumRetries:(NSInteger)dnsNumRetries
                                       enableHttp3:(BOOL)enableHttp3
                                         quicHints:(NSDictionary<NSString *, NSNumber *> *)quicHints
                             quicCanonicalSuffixes:(NSArray<NSString *> *)quicCanonicalSuffixes

mobile/library/objective-c/EnvoyConfiguration.mm

@@ -76,6 +76,7 @@ - (instancetype)initWithConnectTimeoutSeconds:(UInt32)connectTimeoutSeconds
                            dnsPreresolveHostnames:(NSArray<NSString *> *)dnsPreresolveHostnames
                                    enableDNSCache:(BOOL)enableDNSCache
                       dnsCacheSaveIntervalSeconds:(UInt32)dnsCacheSaveIntervalSeconds
+                                    dnsNumRetries:(NSInteger)dnsNumRetries
                                       enableHttp3:(BOOL)enableHttp3
                                         quicHints:(NSDictionary<NSString *, NSNumber *> *)quicHints
                             quicCanonicalSuffixes:(NSArray<NSString *> *)quicCanonicalSuffixes
@@ -122,6 +123,7 @@ - (instancetype)initWithConnectTimeoutSeconds:(UInt32)connectTimeoutSeconds
   self.dnsPreresolveHostnames = dnsPreresolveHostnames;
   self.enableDNSCache = enableDNSCache;
   self.dnsCacheSaveIntervalSeconds = dnsCacheSaveIntervalSeconds;
+  self.dnsNumRetries = dnsNumRetries;
   self.enableHttp3 = enableHttp3;
   self.quicHints = quicHints;
   self.quicCanonicalSuffixes = quicCanonicalSuffixes;
@@ -214,7 +216,9 @@ - (instancetype)initWithConnectTimeoutSeconds:(UInt32)connectTimeoutSeconds
   builder.enablePlatformCertificatesValidation(self.enablePlatformCertificateValidation);
   builder.respectSystemProxySettings(self.respectSystemProxySettings);
   builder.enableDnsCache(self.enableDNSCache, self.dnsCacheSaveIntervalSeconds);
-
+  if (self.dnsNumRetries >= 0) {
+    builder.setDnsNumRetries(self.dnsNumRetries);
+  }
   if (self.upstreamTlsSni != nil) {
     builder.setUpstreamTlsSni([self.upstreamTlsSni toCXXString]);
   }