Add startDaemon and stopDaemon back in MDnsService am: b1e5977ca6 am: 1703a8ab74 am: 74474b0ee5

Original change: https://android-review.googlesource.com/c/platform/system/netd/+/2867838

Change-Id: I1ea5fcaa3b3972e80b7c85fa67955f191db07e5a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

1 files changed, 39 insertions, 10 deletions

diff --git a/server/MDnsService.cpp b/server/MDnsService.cpp
index 0c55e7ae..68359ede 100644
--- a/server/MDnsService.cpp
+++ b/server/MDnsService.cpp
@@ -18,6 +18,7 @@
 
 #include "MDnsService.h"
 
+#include <android-base/properties.h>
 #include <binder/Status.h>
 #include <binder_utils/BinderUtil.h>
 
@@ -27,8 +28,26 @@ using android::net::mdns::aidl::IMDnsEventListener;
 using android::net::mdns::aidl::RegistrationInfo;
 using android::net::mdns::aidl::ResolutionInfo;
 
+using std::literals::chrono_literals::operator""s;
+
 namespace android::net {
 
+#define MDNS_SERVICE_NAME "mdnsd"
+#define MDNS_SERVICE_STATUS "init.svc.mdnsd"
+
+// TODO: DnsResolver has same macro definition but returns ScopedAStatus. Move these macros to
+// BinderUtil.h to do the same permission check.
+#define ENFORCE_ANY_PERMISSION(...)                                \
+    do {                                                           \
+        binder::Status status = checkAnyPermission({__VA_ARGS__}); \
+        if (!status.isOk()) {                                      \
+            return status;                                         \
+        }                                                          \
+    } while (0)
+
+#define ENFORCE_NETWORK_STACK_PERMISSIONS() \
+    ENFORCE_ANY_PERMISSION(PERM_NETWORK_STACK, PERM_MAINLINE_NETWORK_STACK)
+
 status_t MDnsService::start() {
     IPCThreadState::self()->disableBackgroundScheduling(true);
     const status_t ret = BinderService<MDnsService>::publish();
@@ -39,22 +58,32 @@ status_t MDnsService::start() {
 }
 
 binder::Status MDnsService::startDaemon() {
-    // TODO(b/298594687): switch from EX_SERVICE_SPECIFIC to DEPRECATED when tethering module
-    // for 2024-02 release is fully rolled out and prebuilt updated in AP1A.xxxxxx.yy build.
-    // Return EX_SERVICE_SPECIFIC for short-term only because callers in tethering module do not
-    // catch the EX_UNSUPPORTED_OPERATION. It will throw an exception and cause a fatal exception.
-    // The EX_UNSUPPORTED_OPERATION has been catched in tethering module since 2024-02 release.
-    return binder::Status::fromExceptionCode(binder::Status::EX_SERVICE_SPECIFIC);
-    // DEPRECATED;
+    ENFORCE_NETWORK_STACK_PERMISSIONS();
+    if (android::base::GetProperty(MDNS_SERVICE_STATUS, "") == "running") {
+        return binder::Status::fromExceptionCode(-EBUSY);
+    }
+
+    ALOGD("Starting MDNSD");
+    android::base::SetProperty("ctl.start", MDNS_SERVICE_NAME);
+    // To maintain the same behavior as before, the returned value is not checked.
+    android::base::WaitForProperty(MDNS_SERVICE_STATUS, "running", 5s);
+    return binder::Status::ok();
 }
 
 binder::Status MDnsService::stopDaemon() {
-    // TODO(b/298594687): switch to DEPRECATED.
-    return binder::Status::fromExceptionCode(binder::Status::EX_SERVICE_SPECIFIC);
-    // DEPRECATED;
+    ENFORCE_NETWORK_STACK_PERMISSIONS();
+    ALOGD("Stopping MDNSD");
+    android::base::SetProperty("ctl.stop", MDNS_SERVICE_NAME);
+    android::base::WaitForProperty(MDNS_SERVICE_STATUS, "stopped", 5s);
+    return binder::Status::ok();
 }
 
 binder::Status MDnsService::registerService(const RegistrationInfo&) {
+    // TODO(b/298594687): switch from EX_SERVICE_SPECIFIC to DEPRECATED when tethering module
+    // for 2024-02 release is fully rolled out and prebuilt updated in AP1A.xxxxxx.yy build.
+    // Return EX_SERVICE_SPECIFIC for short-term only because callers in tethering module do not
+    // catch the EX_UNSUPPORTED_OPERATION. It will throw an exception and cause a fatal exception.
+    // The EX_UNSUPPORTED_OPERATION has been catched in tethering module since 2024-02 release.
     // TODO(b/298594687): switch to DEPRECATED.
     return binder::Status::fromExceptionCode(binder::Status::EX_SERVICE_SPECIFIC);
     // DEPRECATED;