Initial support for application Zygote.
When an application has requested isolated services to be spawned
from an app zygote, we need to spawn the app zygote itself, and then
ask it to fork an isolated service.
The application zygote currently only creates the class loader, and
doesn't do much else. We keep track of the isolated services that
use the app zygote, and when the last isolated service goes away,
we stop the app zygote itself (after a timeout).
The app zygote itself runs with the app's UID and under the app
seccomp filter. That last one is too restricted, so this currently
only works with SELinux disabled.
Future CLs will add an application callback for preloading.
Test: start multiple isolated services with useAppZygote="true",
verify app_zygote starts, services start as a child of
app_zygote. Stopping all services stops app_zygote as well.
Bug: 111434506
Change-Id: I10ee1d4bd148c9298974d434fbc5e5eccbec16cb
diff --git a/core/java/android/os/ZygoteProcess.java b/core/java/android/os/ZygoteProcess.java
index f136cd6..251c5ee 100644
--- a/core/java/android/os/ZygoteProcess.java
+++ b/core/java/android/os/ZygoteProcess.java
@@ -18,6 +18,7 @@
import android.annotation.NonNull;
import android.annotation.Nullable;
+import android.content.pm.ApplicationInfo;
import android.net.LocalSocket;
import android.net.LocalSocketAddress;
import android.util.Log;
@@ -34,6 +35,7 @@
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Arrays;
+import java.util.Base64;
import java.util.Collections;
import java.util.List;
import java.util.UUID;
@@ -673,6 +675,36 @@
}
/**
+ * Instructs the zygote to pre-load the application code for the given Application.
+ * Only the app zygote supports this function.
+ * TODO preloadPackageForAbi() can probably be removed and the callers an use this instead.
+ */
+ public boolean preloadApp(ApplicationInfo appInfo, String abi) throws ZygoteStartFailedEx,
+ IOException {
+ synchronized (mLock) {
+ ZygoteState state = openZygoteSocketIfNeeded(abi);
+ state.writer.write("2");
+ state.writer.newLine();
+
+ state.writer.write("--preload-app");
+ state.writer.newLine();
+
+ // Zygote args needs to be strings, so in order to pass ApplicationInfo,
+ // write it to a Parcel, and base64 the raw Parcel bytes to the other side.
+ Parcel parcel = Parcel.obtain();
+ appInfo.writeToParcel(parcel, 0 /* flags */);
+ String encodedParcelData = Base64.getEncoder().encodeToString(parcel.marshall());
+ parcel.recycle();
+ state.writer.write(encodedParcelData);
+ state.writer.newLine();
+
+ state.writer.flush();
+
+ return (state.inputStream.readInt() == 0);
+ }
+ }
+
+ /**
* Instructs the zygote to pre-load the classes and native libraries at the given paths
* for the specified abi. Not all zygotes support this function.
*/
@@ -763,6 +795,20 @@
* secondary zygotes that inherit data from the zygote that this object
* communicates with. This returns a new ZygoteProcess representing a connection
* to the newly created zygote. Throws an exception if the zygote cannot be started.
+ *
+ * @param processClass The class to use as the child zygote's main entry
+ * point.
+ * @param niceName A more readable name to use for the process.
+ * @param uid The user-id under which the child zygote will run.
+ * @param gid The group-id under which the child zygote will run.
+ * @param gids Additional group-ids associated with the child zygote process.
+ * @param runtimeFlags Additional flags.
+ * @param seInfo null-ok SELinux information for the child zygote process.
+ * @param abi non-null the ABI of the child zygote
+ * @param acceptedAbiList ABIs this child zygote will accept connections for; this
+ * may be different from <code>abi</code> in case the children
+ * spawned from this Zygote only communicate using ABI-safe methods.
+ * @param instructionSet null-ok the instruction set to use.
*/
public ChildZygoteProcess startChildZygote(final String processClass,
final String niceName,
@@ -770,12 +816,14 @@
int runtimeFlags,
String seInfo,
String abi,
+ String acceptedAbiList,
String instructionSet) {
// Create an unguessable address in the global abstract namespace.
final LocalSocketAddress serverAddress = new LocalSocketAddress(
processClass + "/" + UUID.randomUUID().toString());
- final String[] extraArgs = {Zygote.CHILD_ZYGOTE_SOCKET_NAME_ARG + serverAddress.getName()};
+ final String[] extraArgs = {Zygote.CHILD_ZYGOTE_SOCKET_NAME_ARG + serverAddress.getName(),
+ Zygote.CHILD_ZYGOTE_ABI_LIST_ARG + acceptedAbiList};
Process.ProcessStartResult result;
try {