NativeUtil: Perform range checks on ssid bytes size

NativeUtil.encodeSsid/decodeSsid should perform range checks because the
output/input is coming from binder/hwbinder interfaces which assume
the ssid is not malformed (i.e within spec mandated size range).

Most of the callers of these methods already handle
IllegalArgumentException (including the hidden network list built in
WifiCondControl). This should fix the reported issue of a hidden SSID
added with size > 32 causing crash in wificond.

Bug: 130843221
Test: Device boots up & connects to wifi networks.
Test: Regression tests.
Test: atest com.android.server.wifi
Change-Id: I12d8f3b548a65005932bd8bc1c74de37769b0ee8

1 files changed, 31 insertions, 0 deletions

diff --git a/tests/wifitests/src/com/android/server/wifi/util/NativeUtilTest.java b/tests/wifitests/src/com/android/server/wifi/util/NativeUtilTest.java
index 79dcccfcc..d4bcb479e 100644
--- a/tests/wifitests/src/com/android/server/wifi/util/NativeUtilTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/util/NativeUtilTest.java
@@ -128,6 +128,18 @@ public class NativeUtilTest {
     }
 
     /**
+     * Test that conversion of SSID string with len > 32 to bytes fail.
+     */
+    @Test
+    public void testLargeSsidDecodeFails() throws Exception {
+        try {
+            NativeUtil.decodeSsid("\"asdrewqdfgyuiopldsqwertyuiolhdergcv\"");
+            fail("Expected ssid decode to fail");
+        } catch (IllegalArgumentException e) {
+        }
+    }
+
+    /**
      * Test that conversion of ssid bytes to hex string ssid works.
      */
     @Test
@@ -178,6 +190,25 @@ public class NativeUtilTest {
     }
 
     /**
+     * Test that conversion of SSID bytes with len > 32 to string fail.
+     */
+    @Test
+    public void testLargeSsidEncodeFails() throws Exception {
+        try {
+            NativeUtil.encodeSsid(new ArrayList<>(
+                    Arrays.asList((byte) 0xf5, (byte) 0xe4, (byte) 0xab, (byte) 0x78, (byte) 0x78,
+                            (byte) 0xab, (byte) 0x34, (byte) 0x32, (byte) 0x43, (byte) 0x9a,
+                            (byte) 0xab, (byte) 0x34, (byte) 0x32, (byte) 0x43, (byte) 0x9a,
+                            (byte) 0xab, (byte) 0x34, (byte) 0x32, (byte) 0x43, (byte) 0x9a,
+                            (byte) 0xab, (byte) 0x34, (byte) 0x32, (byte) 0x43, (byte) 0x9a,
+                            (byte) 0xab, (byte) 0x34, (byte) 0x32, (byte) 0x43, (byte) 0x9a,
+                            (byte) 0xab, (byte) 0x34, (byte) 0x32, (byte) 0x43, (byte) 0x9a)));
+            fail("Expected ssid encode to fail");
+        } catch (IllegalArgumentException e) {
+        }
+    }
+
+    /**
      * Test that parsing of quoted SSID to byte array and vice versa works.
      */
     @Test