Uri: check authority and scheme as part of determining URI path

The interpretation of the path depends on whether the scheme or
authority are specified and should be observed when unparcelling
URIs.

Bug: 171966843
Test: atest FrameworksCoreTests:android.net.UriTest
Test: atest com.android.devicehealthchecks.SystemAppCheck
Change-Id: I06981d1c6e387b16df792494523994518848db37
(cherry picked from commit f37a94ae920fa5879c557603fc285942ec4b84b1)

2 files changed, 69 insertions, 7 deletions

diff --git a/core/java/android/net/Uri.java b/core/java/android/net/Uri.java
index 1cb4fe8cf4e7..84fc4f78edc4 100644
--- a/core/java/android/net/Uri.java
+++ b/core/java/android/net/Uri.java
@@ -1194,13 +1194,16 @@ public abstract class Uri implements Parcelable, Comparable<Uri> {
         }
 
         static Uri readFrom(Parcel parcel) {
-            return new HierarchicalUri(
-                parcel.readString8(),
-                Part.readFrom(parcel),
-                PathPart.readFrom(parcel),
-                Part.readFrom(parcel),
-                Part.readFrom(parcel)
-            );
+            final String scheme = parcel.readString8();
+            final Part authority = Part.readFrom(parcel);
+            // In RFC3986 the path should be determined based on whether there is a scheme or
+            // authority present (https://www.rfc-editor.org/rfc/rfc3986.html#section-3.3).
+            final boolean hasSchemeOrAuthority =
+                    (scheme != null && scheme.length() > 0) || !authority.isEmpty();
+            final PathPart path = PathPart.readFrom(hasSchemeOrAuthority, parcel);
+            final Part query = Part.readFrom(parcel);
+            final Part fragment = Part.readFrom(parcel);
+            return new HierarchicalUri(scheme, authority, path, query, fragment);
         }
 
         public int describeContents() {
@@ -2259,6 +2262,11 @@ public abstract class Uri implements Parcelable, Comparable<Uri> {
             }
         }
 
+        static PathPart readFrom(boolean hasSchemeOrAuthority, Parcel parcel) {
+            final PathPart path = readFrom(parcel);
+            return hasSchemeOrAuthority ? makeAbsolute(path) : path;
+        }
+
         /**
          * Creates a path from the encoded string.
          *
diff --git a/core/tests/coretests/src/android/net/UriTest.java b/core/tests/coretests/src/android/net/UriTest.java
index f20220c4ab9b..670aefd21d36 100644
--- a/core/tests/coretests/src/android/net/UriTest.java
+++ b/core/tests/coretests/src/android/net/UriTest.java
@@ -48,6 +48,7 @@ public class UriTest extends TestCase {
     public void testParcelling() {
         parcelAndUnparcel(Uri.parse("foo:bob%20lee"));
         parcelAndUnparcel(Uri.fromParts("foo", "bob lee", "fragment"));
+        parcelAndUnparcel(Uri.fromParts("https", "www.google.com", null));
         parcelAndUnparcel(new Uri.Builder()
             .scheme("http")
             .authority("crazybob.org")
@@ -873,9 +874,62 @@ public class UriTest extends TestCase {
             Throwable targetException = expected.getTargetException();
             // Check that the exception was thrown for the correct reason.
             assertEquals("Unknown representation: 0", targetException.getMessage());
+        } finally {
+            parcel.recycle();
         }
     }
 
+    private Uri buildUriFromRawParcel(boolean argumentsEncoded,
+                                      String scheme,
+                                      String authority,
+                                      String path,
+                                      String query,
+                                      String fragment) {
+        // Representation value (from AbstractPart.REPRESENTATION_{ENCODED,DECODED}).
+        final int representation = argumentsEncoded ? 1 : 2;
+        Parcel parcel = Parcel.obtain();
+        try {
+            parcel.writeInt(3);  // hierarchical
+            parcel.writeString8(scheme);
+            parcel.writeInt(representation);
+            parcel.writeString8(authority);
+            parcel.writeInt(representation);
+            parcel.writeString8(path);
+            parcel.writeInt(representation);
+            parcel.writeString8(query);
+            parcel.writeInt(representation);
+            parcel.writeString8(fragment);
+            parcel.setDataPosition(0);
+            return Uri.CREATOR.createFromParcel(parcel);
+        } finally {
+            parcel.recycle();
+        }
+    }
+
+    public void testUnparcelMalformedPath() {
+        // Regression tests for b/171966843.
+
+        // Test cases with arguments encoded (covering testing `scheme` * `authority` options).
+        Uri uri0 = buildUriFromRawParcel(true, "https", "google.com", "@evil.com", null, null);
+        assertEquals("https://google.com/@evil.com", uri0.toString());
+        Uri uri1 = buildUriFromRawParcel(true, null, "google.com", "@evil.com", "name=spark", "x");
+        assertEquals("//google.com/@evil.com?name=spark#x", uri1.toString());
+        Uri uri2 = buildUriFromRawParcel(true, "http:", null, "@evil.com", null, null);
+        assertEquals("http::/@evil.com", uri2.toString());
+        Uri uri3 = buildUriFromRawParcel(true, null, null, "@evil.com", null, null);
+        assertEquals("@evil.com", uri3.toString());
+
+        // Test cases with arguments not encoded (covering testing `scheme` * `authority` options).
+        Uri uriA = buildUriFromRawParcel(false, "https", "google.com", "@evil.com", null, null);
+        assertEquals("https://google.com/%40evil.com", uriA.toString());
+        Uri uriB = buildUriFromRawParcel(false, null, "google.com", "@evil.com", null, null);
+        assertEquals("//google.com/%40evil.com", uriB.toString());
+        Uri uriC = buildUriFromRawParcel(false, "http:", null, "@evil.com", null, null);
+        assertEquals("http::/%40evil.com", uriC.toString());
+        Uri uriD = buildUriFromRawParcel(false, null, null, "@evil.com", "name=spark", "y");
+        assertEquals("%40evil.com?name%3Dspark#y", uriD.toString());
+    }
+
     public void testToSafeString() {
         checkToSafeString("tel:xxxxxx", "tel:Google");
         checkToSafeString("tel:xxxxxxxxxx", "tel:1234567890");