feat: support mqtt wildcard resource matching

aws-greengrass · Sep 11, 2024 · c644dbe · c644dbe
1 parent 1d2958e
commit c644dbe
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Showing 5 changed files with 101 additions and 18 deletions.
diff --git a/src/integrationtests/java/com/aws/greengrass/integrationtests/policy/PolicyTest.java b/src/integrationtests/java/com/aws/greengrass/integrationtests/policy/PolicyTest.java
@@ -274,7 +274,7 @@ public static Stream<Arguments> authzRequests() {
                                 .resource("mqtt:topic:myThing/world")
                                 .expectedResult(false)
                                 .build(),
-                        // mqtt wildcards eval not supported
+                        // mqtt wildcards eval not supported by default
                         AuthZRequest.builder()
                                 .thingName("myThing")
                                 .operation("mqtt:subscribe")
@@ -289,6 +289,27 @@ public static Stream<Arguments> authzRequests() {
                                 .build()
                 )),
 
+                Arguments.of("mqtt-wildcards-in-resource.yaml", Arrays.asList(
+                        AuthZRequest.builder()
+                                .thingName("myThing")
+                                .operation("mqtt:publish")
+                                .resource("mqtt:topic:*/myThing/*")
+                                .expectedResult(true)
+                                .build(),
+                        AuthZRequest.builder()
+                                .thingName("myThing")
+                                .operation("mqtt:publish")
+                                .resource("mqtt:topic:hello/myThing/world")
+                                .expectedResult(true)
+                                .build(),
+                        AuthZRequest.builder()
+                                .thingName("myThing")
+                                .operation("mqtt:subscribe")
+                                .resource("mqtt:topic:myThing/test/test/test/test")
+                                .expectedResult(true)
+                                .build()
+                )),
+
                 Arguments.of("variables-and-wildcards.yaml", Arrays.asList(
                         AuthZRequest.builder()
                                 .thingName("myThing")

diff --git a/...ests/resources/com/aws/greengrass/integrationtests/policy/mqtt-wildcards-in-resource.yaml b/...ests/resources/com/aws/greengrass/integrationtests/policy/mqtt-wildcards-in-resource.yaml
@@ -0,0 +1,35 @@
+---
+services:
+  aws.greengrass.Nucleus:
+    configuration:
+      runWithDefault:
+        posixUser: nobody
+        windowsUser: integ-tester
+      logging:
+        level: "DEBUG"
+  aws.greengrass.clientdevices.Auth:
+    configuration:
+      enableMqttWildcardEvaluation: true
+      deviceGroups:
+        formatVersion: "2021-03-05"
+        definitions:
+          myThing:
+            selectionRule: "thingName: myThing"
+            policyName: "thingAccessPolicy"
+        policies:
+          thingAccessPolicy:
+            publish:
+              statementDescription: "mqtt publish"
+              operations:
+                - "mqtt:publish"
+              resources:
+                - "mqtt:topic:*/myThing/*"
+            subscribe:
+              statementDescription: "mqtt subscribe"
+              operations:
+                - "mqtt:subscribe"
+              resources:
+                - "mqtt:topic:${iot:Connection.Thing.ThingName}/+/test/#"
+  main:
+    dependencies:
+      - aws.greengrass.clientdevices.Auth
diff --git a/src/main/java/com/aws/greengrass/clientdevices/auth/ClientDevicesAuthService.java b/src/main/java/com/aws/greengrass/clientdevices/auth/ClientDevicesAuthService.java
@@ -170,6 +170,8 @@ private void subscribeToConfigChanges() {
     private void onConfigurationChanged() {
         try {
             cdaConfiguration = CDAConfiguration.from(cdaConfiguration, getConfig());
+            // TODO decouple
+            context.get(PermissionEvaluationUtils.class).setCdaConfiguration(cdaConfiguration);
         } catch (URISyntaxException e) {
             serviceErrored(e);
         }

diff --git a/src/main/java/com/aws/greengrass/clientdevices/auth/PermissionEvaluationUtils.java b/src/main/java/com/aws/greengrass/clientdevices/auth/PermissionEvaluationUtils.java
@@ -6,6 +6,7 @@
 package com.aws.greengrass.clientdevices.auth;
 
 import com.aws.greengrass.authorization.WildcardTrie;
+import com.aws.greengrass.clientdevices.auth.configuration.CDAConfiguration;
 import com.aws.greengrass.clientdevices.auth.configuration.GroupManager;
 import com.aws.greengrass.clientdevices.auth.configuration.Permission;
 import com.aws.greengrass.clientdevices.auth.exception.PolicyException;
@@ -14,6 +15,7 @@
 import com.aws.greengrass.logging.impl.LogManager;
 import com.aws.greengrass.util.Utils;
 import lombok.Builder;
+import lombok.Setter;
 import lombok.Value;
 import org.apache.commons.lang3.StringUtils;
 
@@ -36,6 +38,8 @@ public final class PermissionEvaluationUtils {
             "Resource is malformed, must be of the form: "
             + "([a-zA-Z]+):([a-zA-Z]+):" + RESOURCE_NAME_PATTERN.pattern();
     private final GroupManager groupManager;
+    @Setter
+    private volatile CDAConfiguration cdaConfiguration;
 
     /**
      * Constructor for PermissionEvaluationUtils.
@@ -134,9 +138,27 @@ private boolean compareResource(Resource requestResource, String policyResource)
             return true;
         }
 
-        WildcardTrie wildcardTrie = new WildcardTrie();
-        wildcardTrie.add(policyResource);
-        return wildcardTrie.matchesStandard(requestResource.getResourceStr());
+        if (matchMqttWildcards()) {
+            String name = extractResourceName(policyResource);
+            WildcardTrie trie = new WildcardTrie();
+            trie.add(name);
+            return trie.matchesMQTT(requestResource.getResourceName());
+        } else {
+            WildcardTrie trie = new WildcardTrie();
+            trie.add(policyResource);
+            return trie.matchesStandard(requestResource.getResourceStr());
+        }
+    }
+
+    private String extractResourceName(String resource) {
+        // resource is considered valid at this point, so don't need to duplicate validation from parseResource
+        String typeAndName = resource.substring(resource.indexOf(':') + 1);
+        return typeAndName.substring(typeAndName.indexOf(':') + 1);
+    }
+
+    private boolean matchMqttWildcards() {
+        CDAConfiguration config = cdaConfiguration;
+        return config != null && config.isEnableMqttWildcardEvaluation();
     }
 
     private Operation parseOperation(String operationStr) throws PolicyException {

diff --git a/src/main/java/com/aws/greengrass/clientdevices/auth/configuration/CDAConfiguration.java b/src/main/java/com/aws/greengrass/clientdevices/auth/configuration/CDAConfiguration.java
@@ -10,6 +10,8 @@
 import com.aws.greengrass.clientdevices.auth.configuration.events.MetricsConfigurationChanged;
 import com.aws.greengrass.clientdevices.auth.configuration.events.SecurityConfigurationChanged;
 import com.aws.greengrass.config.Topics;
+import com.aws.greengrass.util.Coerce;
+import lombok.Builder;
 import lombok.Getter;
 
 import java.net.URISyntaxException;
@@ -48,23 +50,19 @@
  * |
  * </p>
  */
+@Builder
 public final class CDAConfiguration {
 
+    public static final String ENABLE_MQTT_WILDCARD_EVALUATION = "enableMqttWildcardEvaluation";
+
+    private final DomainEvents domainEvents;
     private final RuntimeConfiguration runtime;
-    private final SecurityConfiguration security;
     @Getter
     private final CAConfiguration certificateAuthorityConfiguration;
+    private final SecurityConfiguration security;
     private final MetricsConfiguration metricsConfiguration;
-    private final DomainEvents domainEvents;
-
-    private CDAConfiguration(DomainEvents domainEvents, RuntimeConfiguration runtime, CAConfiguration ca,
-                             SecurityConfiguration security, MetricsConfiguration metricsConfiguration) {
-        this.domainEvents = domainEvents;
-        this.runtime = runtime;
-        this.security = security;
-        this.certificateAuthorityConfiguration = ca;
-        this.metricsConfiguration = metricsConfiguration;
-    }
+    @Getter
+    private final boolean enableMqttWildcardEvaluation;
 
     /**
      * Creates the CDA (Client Device Auth) Service configuration. And allows it to be available in the context with the
@@ -80,9 +78,14 @@ public static CDAConfiguration from(CDAConfiguration existingConfig, Topics topi
 
         DomainEvents domainEvents = topics.getContext().get(DomainEvents.class);
 
-        CDAConfiguration newConfig = new CDAConfiguration(domainEvents, RuntimeConfiguration.from(runtimeTopics),
-                CAConfiguration.from(serviceConfiguration), SecurityConfiguration.from(serviceConfiguration),
-                MetricsConfiguration.from(serviceConfiguration));
+        CDAConfiguration newConfig = CDAConfiguration.builder()
+                .domainEvents(domainEvents)
+                .runtime(RuntimeConfiguration.from(runtimeTopics))
+                .certificateAuthorityConfiguration(CAConfiguration.from(serviceConfiguration))
+                .security(SecurityConfiguration.from(serviceConfiguration))
+                .metricsConfiguration(MetricsConfiguration.from(serviceConfiguration))
+                .enableMqttWildcardEvaluation(Coerce.toBoolean(serviceConfiguration.find(ENABLE_MQTT_WILDCARD_EVALUATION)))
+                .build();
 
         newConfig.triggerChanges(newConfig, existingConfig);