Keep case in MdnsServiceInfo attributes
Although case should not matter when comparing attributes,
converting all keys to lowercase breaks NsdServiceInfo APIs which
provide the original case to the caller.
Use a TreeMap with a case-insensitive comparator to ignore case when
querying keys, while keeping case information in the map.
Bug: 270885892
Test: atest MdnsServiceInfoTest
Change-Id: Id15947b1e8650eb6b59126c5d2dc8624ae4f8100
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceInfo.java b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceInfo.java
index 938fc3f..64df46e 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsServiceInfo.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsServiceInfo.java
@@ -31,10 +31,10 @@
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
-import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;
+import java.util.TreeMap;
/**
* A class representing a discovered mDNS service instance.
@@ -205,17 +205,14 @@
// compatibility. We should prefer only {@code textEntries} if it's not null.
List<TextEntry> entries =
(this.textEntries != null) ? this.textEntries : parseTextStrings(this.textStrings);
- Map<String, byte[]> attributes = new HashMap<>(entries.size());
+ // The map of attributes is case-insensitive.
+ final Map<String, byte[]> attributes = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
for (TextEntry entry : entries) {
- String key = entry.getKey().toLowerCase(Locale.ENGLISH);
-
// Per https://datatracker.ietf.org/doc/html/rfc6763#section-6.4, only the first entry
// of the same key should be accepted:
// If a client receives a TXT record containing the same key more than once, then the
// client MUST silently ignore all but the first occurrence of that attribute.
- if (!attributes.containsKey(key)) {
- attributes.put(key, entry.getValue());
- }
+ attributes.putIfAbsent(entry.getKey(), entry.getValue());
}
this.attributes = Collections.unmodifiableMap(attributes);
this.interfaceIndex = interfaceIndex;
@@ -311,12 +308,12 @@
*/
@Nullable
public byte[] getAttributeAsBytes(@NonNull String key) {
- return attributes.get(key.toLowerCase(Locale.ENGLISH));
+ return attributes.get(key);
}
/** Returns an immutable map of all attributes. */
public Map<String, String> getAttributes() {
- Map<String, String> map = new HashMap<>(attributes.size());
+ Map<String, String> map = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
for (Map.Entry<String, byte[]> kv : attributes.entrySet()) {
final byte[] value = kv.getValue();
map.put(kv.getKey(), value == null ? null : new String(value, UTF_8));
diff --git a/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceInfoTest.java b/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceInfoTest.java
index 76728cf..4db0f1a 100644
--- a/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceInfoTest.java
+++ b/tests/unit/java/com/android/server/connectivity/mdns/MdnsServiceInfoTest.java
@@ -119,6 +119,26 @@
}
@Test
+ public void constructor_createWithUppercaseKeys_correctAttributes() {
+ MdnsServiceInfo info =
+ new MdnsServiceInfo(
+ "my-mdns-service",
+ new String[] {"_testtype", "_tcp"},
+ List.of(),
+ new String[] {"my-host", "local"},
+ 12345,
+ "192.168.1.1",
+ "2001::1",
+ List.of("KEY=Value"),
+ /* textEntries= */ null);
+
+ assertEquals("Value", info.getAttributeByKey("key"));
+ assertEquals("Value", info.getAttributeByKey("KEY"));
+ assertEquals(1, info.getAttributes().size());
+ assertEquals("KEY", info.getAttributes().keySet().iterator().next());
+ }
+
+ @Test
public void getInterfaceIndex_constructorWithDefaultValues_returnsMinusOne() {
MdnsServiceInfo info =
new MdnsServiceInfo(