commit 5026b3ea9339a29aa831b7976daec993f5a01d5c
author Lorenzo Colitti <lorenzo@google.com> Mon May 10 00:49:14 2021 +0900
committer Lorenzo Colitti <lorenzo@google.com> Tue May 11 22:47:03 2021 +0900
tree 9834e9230dc25ee49f415fbb10e61ebbd81299cf
parent 1df16c6f8f69cb2c396657cebefa8b8b514213ae

Do not automatically redact TransportInfo objects.

Currently, NetworkCapabilities always redacts the TransportInfo
objects it contains whenever a defensive copy is made. This makes
it impossible to make a defensive copy on a TransportInfo
parcelled from another process without redacting it.

Stop redacting by default; instead rely on ConnectivityService
explicitly calling NetworkCapabilities' redacting constructor
when it returns a NetworkCapabilities object to an app via a
callback or synchronous call. This is currently done by
- createWithLocationInfoSanitizedIfNecessaryWhenParceled, which
  is called from callCallbackForRequest, getNetworkCapabilities,
  and getDefaultNetworkCapabilitiesForUser.
- getNetworkCapabilitiesWithoutUids, which is used when sending
  ConnectivityDiagnosticsManager callbacks. In this method,
  unconditionally redact all information, which is what the code
  did previously due to the default redaction setting for empty
  NetworkCapabilities objects being REDACT_ALL.

Bug: 183938194
Test: atest NetworkCapabilitiesTest
Test: atest FrameworksNetTests CtsNetTestCases HostsideVpnTests
Change-Id: I3108ee94cb0930958e071ba678c3554525b0db82

framework/src/android/net/NetworkCapabilities.java

diff --git a/framework/src/android/net/NetworkCapabilities.java b/framework/src/android/net/NetworkCapabilities.java
index 0bafd5b..d0b1075 100644
--- a/framework/src/android/net/NetworkCapabilities.java
+++ b/framework/src/android/net/NetworkCapabilities.java
@@ -139,19 +139,13 @@
      */
     private String mRequestorPackageName;
 
-    /**
-     * Indicates what fields should be redacted from this instance.
-     */
-    private final @RedactionType long mRedactions;
-
     public NetworkCapabilities() {
-        mRedactions = REDACT_ALL;
         clearAll();
         mNetworkCapabilities = DEFAULT_CAPABILITIES;
     }
 
     public NetworkCapabilities(NetworkCapabilities nc) {
-        this(nc, REDACT_ALL);
+        this(nc, REDACT_NONE);
     }
 
     /**
@@ -163,10 +157,12 @@
      * @hide
      */
     public NetworkCapabilities(@Nullable NetworkCapabilities nc, @RedactionType long redactions) {
-        mRedactions = redactions;
         if (nc != null) {
             set(nc);
         }
+        if (mTransportInfo != null) {
+            mTransportInfo = nc.mTransportInfo.makeCopy(redactions);
+        }
     }
 
     /**
@@ -175,14 +171,6 @@
      * @hide
      */
     public void clearAll() {
-        // Ensures that the internal copies maintained by the connectivity stack does not set it to
-        // anything other than |REDACT_ALL|.
-        if (mRedactions != REDACT_ALL) {
-            // This is needed because the current redaction mechanism relies on redaction while
-            // parceling.
-            throw new UnsupportedOperationException(
-                    "Cannot clear NetworkCapabilities when mRedactions is set");
-        }
         mNetworkCapabilities = mTransportTypes = mForbiddenNetworkCapabilities = 0;
         mLinkUpBandwidthKbps = mLinkDownBandwidthKbps = LINK_BANDWIDTH_UNSPECIFIED;
         mNetworkSpecifier = null;
@@ -211,7 +199,7 @@
         mLinkDownBandwidthKbps = nc.mLinkDownBandwidthKbps;
         mNetworkSpecifier = nc.mNetworkSpecifier;
         if (nc.getTransportInfo() != null) {
-            setTransportInfo(nc.getTransportInfo().makeCopy(mRedactions));
+            setTransportInfo(nc.getTransportInfo());
         } else {
             setTransportInfo(null);
         }