This change introduces a new CEL extension that provides types and functions for working with IP addresses and CIDR ranges. The extension defines net.IP and net.CIDR opaque types.

extensions/BUILD.bazel

@@ -37,6 +37,11 @@ java_library(
     exports = ["//extensions/src/main/java/dev/cel/extensions:math"],
 )
 
+java_library(
+    name = "network",
+    exports = ["//extensions/src/main/java/dev/cel/extensions:network"],
+)
+
 java_library(
     name = "optional_library",
     exports = ["//extensions/src/main/java/dev/cel/extensions:optional_library"],

extensions/src/main/java/dev/cel/extensions/BUILD.bazel

@@ -34,6 +34,7 @@ java_library(
         ":encoders",
         ":lists",
         ":math",
+        ":network",
         ":optional_library",
         ":protos",
         ":regex",
@@ -135,6 +136,25 @@ java_library(
     ],
 )
 
+java_library(
+    name = "network",
+    srcs = ["CelNetworkExtensions.java"],
+    deps = [
+        ":extension_library",
+        "//checker:checker_builder",
+        "//common:compiler_common",
+        "//common/types",
+        "//common/types:type_providers",
+        "//compiler:compiler_builder",
+        "//java/com/google/common/net",
+        "//java/com/google/net/base:base-core",
+        "//runtime",
+        "//runtime:function_binding",
+        "@maven//:com_google_errorprone_error_prone_annotations",
+        "@maven//:com_google_guava_guava",
+    ],
+)
+
 java_library(
     name = "bindings",
     srcs = ["CelBindingsExtensions.java"],

extensions/src/main/java/dev/cel/extensions/CelExtensions.java

@@ -36,6 +36,7 @@ public final class CelExtensions {
   private static final CelRegexExtensions REGEX_EXTENSIONS = new CelRegexExtensions();
   private static final CelComprehensionsExtensions COMPREHENSIONS_EXTENSIONS =
       new CelComprehensionsExtensions();
+  private static final CelNetworkExtensions NETWORK_EXTENSIONS = new CelNetworkExtensions();
 
   /**
    * Implementation of optional values.
@@ -319,6 +320,18 @@ public static CelComprehensionsExtensions comprehensions() {
     return COMPREHENSIONS_EXTENSIONS;
   }
 
+  /**
+   * Extended functions for Network manipulation.
+   *
+   * <p>Refer to README.md for available functions.
+   *
+   * <p>This will include all functions denoted in {@link CelNetworkExtensions.Function}, including
+   * any future additions.
+   */
+  public static CelNetworkExtensions network() {
+    return NETWORK_EXTENSIONS;
+  }
+
   /**
    * Retrieves all function names used by every extension libraries.
    *
@@ -339,38 +352,30 @@ public static ImmutableSet<String> getAllFunctionNames() {
                 .map(CelListsExtensions.Function::getFunction),
             stream(CelRegexExtensions.Function.values())
                 .map(CelRegexExtensions.Function::getFunction),
+            stream(CelNetworkExtensions.Function.values())
+                .map(CelNetworkExtensions.Function::getFunction),
             stream(CelComprehensionsExtensions.Function.values())
                 .map(CelComprehensionsExtensions.Function::getFunction))
         .collect(toImmutableSet());
   }
 
   public static CelExtensionLibrary<? extends CelExtensionLibrary.FeatureSet> getExtensionLibrary(
       String name, CelOptions options) {
-    switch (name) {
-      case "bindings":
-        return CelBindingsExtensions.library();
-      case "encoders":
-        return CelEncoderExtensions.library(options);
-      case "lists":
-        return CelListsExtensions.library();
-      case "math":
-        return CelMathExtensions.library(options);
-      case "optional":
-        return CelOptionalLibrary.library();
-      case "protos":
-        return CelProtoExtensions.library();
-      case "regex":
-        return CelRegexExtensions.library();
-      case "sets":
-        return CelSetsExtensions.library(options);
-      case "strings":
-        return CelStringExtensions.library();
-      case "comprehensions":
-        return CelComprehensionsExtensions.library();
+    return switch (name) {
+      case "bindings" -> CelBindingsExtensions.library();
+      case "encoders" -> CelEncoderExtensions.library(options);
+      case "lists" -> CelListsExtensions.library();
+      case "math" -> CelMathExtensions.library(options);
+      case "network" -> CelNetworkExtensions.library();
+      case "optional" -> CelOptionalLibrary.library();
+      case "protos" -> CelProtoExtensions.library();
+      case "regex" -> CelRegexExtensions.library();
+      case "sets" -> CelSetsExtensions.library(options);
+      case "strings" -> CelStringExtensions.library();
+      case "comprehensions" -> CelComprehensionsExtensions.library();
       // TODO: add support for remaining standard extensions
-      default:
-        throw new IllegalArgumentException("Unknown standard extension '" + name + "'");
-    }
+      default -> throw new IllegalArgumentException("Unknown standard extension '" + name + "'");
+    };
   }
 
   private CelExtensions() {}