Exit early if ACLs are enabled and Service Name does not match

ServiceAccountName in podSpec

Signed-off-by: Ashwin Venkatesh <ashwin@hashicorp.com>

connect-inject/container_init.go

@@ -81,6 +81,12 @@ func (h *Handler) containerInit(pod *corev1.Pod, k8sNamespace string) (corev1.Co
 		panic("No service found. This should be impossible since we default it.")
 	}
 
+	// When ACLs are enabled, the ACL token returned from `consul login` is only
+	// valid for a service with the same name as the ServiceAccountName.
+	if data.AuthMethod != "" && data.ServiceName != pod.Spec.ServiceAccountName {
+		return corev1.Container{}, fmt.Errorf("serviceAccountName %q does not match service name %q", pod.Spec.ServiceAccountName, data.ServiceName)
+	}
+
 	// If a port is specified, then we determine the value of that port
 	// and register that port for the host service.
 	if raw, ok := pod.Annotations[annotationPort]; ok && raw != "" {

connect-inject/container_init_test.go

@@ -627,6 +627,7 @@ func TestHandlerContainerInit_namespacesEnabled(t *testing.T) {
 						},
 					},
 				},
+				ServiceAccountName: "web",
 			},
 		}
 	}
@@ -1323,6 +1324,7 @@ func TestHandlerContainerInit_authMethod(t *testing.T) {
 					},
 				},
 			},
+			ServiceAccountName: "foo",
 		},
 	}
 	container, err := h.containerInit(pod, k8sNamespace)
@@ -1373,6 +1375,7 @@ func TestHandlerContainerInit_authMethodAndCentralConfig(t *testing.T) {
 					},
 				},
 			},
+			ServiceAccountName: "foo",
 		},
 	}
 	container, err := h.containerInit(pod, k8sNamespace)
@@ -1514,3 +1517,51 @@ func TestHandlerContainerInit_Resources(t *testing.T) {
 		},
 	}, container.Resources)
 }
+
+func TestHandlerContainerInit_MismatchedServiceNameServiceAccountNameWithACLsEnabled(t *testing.T) {
+	require := require.New(t)
+	h := Handler{
+		AuthMethod: "auth-method",
+	}
+	pod := &corev1.Pod{
+		ObjectMeta: metav1.ObjectMeta{
+			Annotations: map[string]string{
+				annotationService: "foo",
+			},
+		},
+		Spec: corev1.PodSpec{
+			Containers: []corev1.Container{
+				{
+					Name: "serviceName",
+				},
+			},
+			ServiceAccountName: "notServiceName",
+		},
+	}
+
+	_, err := h.containerInit(pod, k8sNamespace)
+	require.EqualError(err, `serviceAccountName "notServiceName" does not match service name "foo"`)
+}
+
+func TestHandlerContainerInit_MismatchedServiceNameServiceAccountNameWithACLsDisabled(t *testing.T) {
+	require := require.New(t)
+	h := Handler{}
+	pod := &corev1.Pod{
+		ObjectMeta: metav1.ObjectMeta{
+			Annotations: map[string]string{
+				annotationService: "foo",
+			},
+		},
+		Spec: corev1.PodSpec{
+			Containers: []corev1.Container{
+				{
+					Name: "serviceName",
+				},
+			},
+			ServiceAccountName: "notServiceName",
+		},
+	}
+
+	_, err := h.containerInit(pod, k8sNamespace)
+	require.NoError(err)
+}