VPN: stop daemons by closing the control sockets.
As init now uses SIGKILL to stop daemons, performing graceful shutdown
becomes impossible. Here we implement our own solution by asking daemons
to monitor the control socket and terminate when it is closed.
Change-Id: I07a28807173a81b7f95e70f4193e974317acf88a
diff --git a/services/java/com/android/server/connectivity/Vpn.java b/services/java/com/android/server/connectivity/Vpn.java
index 6b65e07..55e0678 100644
--- a/services/java/com/android/server/connectivity/Vpn.java
+++ b/services/java/com/android/server/connectivity/Vpn.java
@@ -388,6 +388,7 @@
private final VpnConfig mConfig;
private final String[] mDaemons;
private final String[][] mArguments;
+ private final LocalSocket[] mSockets;
private final String mOuterInterface;
private final LegacyVpnInfo mInfo;
@@ -398,6 +399,7 @@
mConfig = config;
mDaemons = new String[] {"racoon", "mtpd"};
mArguments = new String[][] {racoon, mtpd};
+ mSockets = new LocalSocket[mDaemons.length];
mInfo = new LegacyVpnInfo();
// This is the interface which VPN is running on.
@@ -416,10 +418,14 @@
}
public void exit() {
- // We assume that everything is reset after the daemons die.
+ // We assume that everything is reset after stopping the daemons.
interrupt();
- for (String daemon : mDaemons) {
- SystemProperties.set("ctl.stop", daemon);
+ for (LocalSocket socket : mSockets) {
+ try {
+ socket.close();
+ } catch (Exception e) {
+ // ignore
+ }
}
}
@@ -462,15 +468,10 @@
checkpoint(false);
mInfo.state = LegacyVpnInfo.STATE_INITIALIZING;
- // First stop the daemons.
- for (String daemon : mDaemons) {
- SystemProperties.set("ctl.stop", daemon);
- }
-
// Wait for the daemons to stop.
for (String daemon : mDaemons) {
String key = "init.svc." + daemon;
- while (!"stopped".equals(SystemProperties.get(key))) {
+ while (!"stopped".equals(SystemProperties.get(key, "stopped"))) {
checkpoint(true);
}
}
@@ -511,27 +512,27 @@
}
// Create the control socket.
- LocalSocket socket = new LocalSocket();
+ mSockets[i] = new LocalSocket();
LocalSocketAddress address = new LocalSocketAddress(
daemon, LocalSocketAddress.Namespace.RESERVED);
// Wait for the socket to connect.
while (true) {
try {
- socket.connect(address);
+ mSockets[i].connect(address);
break;
} catch (Exception e) {
// ignore
}
checkpoint(true);
}
- socket.setSoTimeout(500);
+ mSockets[i].setSoTimeout(500);
// Send over the arguments.
- OutputStream out = socket.getOutputStream();
+ OutputStream out = mSockets[i].getOutputStream();
for (String argument : arguments) {
byte[] bytes = argument.getBytes(Charsets.UTF_8);
- if (bytes.length > 0xFFFF) {
+ if (bytes.length >= 0xFFFF) {
throw new IllegalArgumentException("Argument is too large");
}
out.write(bytes.length >> 8);
@@ -539,11 +540,12 @@
out.write(bytes);
checkpoint(false);
}
+ out.write(0xFF);
+ out.write(0xFF);
out.flush();
- socket.shutdownOutput();
// Wait for End-of-File.
- InputStream in = socket.getInputStream();
+ InputStream in = mSockets[i].getInputStream();
while (true) {
try {
if (in.read() == -1) {
@@ -554,7 +556,6 @@
}
checkpoint(true);
}
- socket.close();
}
// Wait for the daemons to create the new state.
@@ -631,6 +632,13 @@
Log.i(TAG, "Aborting", e);
exit();
} finally {
+ // Kill the daemons if they fail to stop.
+ if (mInfo.state == LegacyVpnInfo.STATE_INITIALIZING) {
+ for (String daemon : mDaemons) {
+ SystemProperties.set("ctl.stop", daemon);
+ }
+ }
+
// Do not leave an unstable state.
if (mInfo.state == LegacyVpnInfo.STATE_INITIALIZING ||
mInfo.state == LegacyVpnInfo.STATE_CONNECTING) {