Fix NullPointerException on addErrorCode when input is Invalid error code am: ad90e1bfe1

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/NetworkStack/+/11987398

Change-Id: I78c4025468341c9a515bcedd83cf19ea6795e283

2 files changed, 24 insertions, 15 deletions

diff --git a/src/com/android/networkstack/metrics/IpProvisioningMetrics.java b/src/com/android/networkstack/metrics/IpProvisioningMetrics.java
index 1f969d4..64e173d 100644
--- a/src/com/android/networkstack/metrics/IpProvisioningMetrics.java
+++ b/src/com/android/networkstack/metrics/IpProvisioningMetrics.java
@@ -120,12 +120,21 @@ public class IpProvisioningMetrics {
                 transSuccess ? HostnameTransResult.HTR_SUCCESS : HostnameTransResult.HTR_FAILURE);
     }
 
+    private static DhcpErrorCode dhcpErrorFromNumberSafe(int number) {
+        // See DhcpErrorCode.errorCodeWithOption
+        // TODO: add a DhcpErrorCode method to extract the code;
+        //       or replace legacy error codes with the new metrics.
+        final DhcpErrorCode error = DhcpErrorCode.forNumber(number & 0xFFFF0000);
+        if (error == null) return DhcpErrorCode.ET_UNKNOWN;
+        return error;
+    }
+
     /**
      * write the DHCP error code into DhcpSession.
      */
     public void addDhcpErrorCode(final int errorCode) {
         if (mDhcpSessionBuilder.getErrorCodeCount() >= MAX_DHCP_ERROR_COUNT) return;
-        mDhcpSessionBuilder.addErrorCode(DhcpErrorCode.forNumber(errorCode));
+        mDhcpSessionBuilder.addErrorCode(dhcpErrorFromNumberSafe(errorCode));
     }
 
     /**
diff --git a/tests/unit/src/com/android/networkstack/metrics/NetworkIpProvisioningMetricsTest.java b/tests/unit/src/com/android/networkstack/metrics/NetworkIpProvisioningMetricsTest.java
index 08812b7..01d94e2 100644
--- a/tests/unit/src/com/android/networkstack/metrics/NetworkIpProvisioningMetricsTest.java
+++ b/tests/unit/src/com/android/networkstack/metrics/NetworkIpProvisioningMetricsTest.java
@@ -16,6 +16,7 @@
 
 package com.android.networkstack.metrics;
 
+import android.net.dhcp.DhcpPacket;
 import android.net.metrics.DhcpErrorEvent;
 import android.stats.connectivity.DhcpErrorCode;
 import android.stats.connectivity.DhcpFeature;
@@ -64,25 +65,24 @@ public class NetworkIpProvisioningMetricsTest {
         final NetworkIpProvisioningReported mStats;
         final IpProvisioningMetrics mMetrics = new IpProvisioningMetrics();
         mMetrics.reset();
-        mMetrics.addDhcpErrorCode(DhcpErrorEvent.DHCP_ERROR);
-        mMetrics.addDhcpErrorCode(DhcpErrorEvent.L2_WRONG_ETH_TYPE);
-        mMetrics.addDhcpErrorCode(DhcpErrorEvent.L3_INVALID_IP);
-        mMetrics.addDhcpErrorCode(DhcpErrorEvent.L4_WRONG_PORT);
         mMetrics.addDhcpErrorCode(DhcpErrorEvent.BOOTP_TOO_SHORT);
-        mMetrics.addDhcpErrorCode(DhcpErrorEvent.DHCP_NO_COOKIE);
+        mMetrics.addDhcpErrorCode(DhcpErrorEvent.errorCodeWithOption(
+                DhcpErrorEvent.BUFFER_UNDERFLOW, DhcpPacket.DHCP_HOST_NAME));
+        // Write the incorrect input number 50000 as DHCP error number
+        int incorrectErrorCodeNumber = 50000;
+        mMetrics.addDhcpErrorCode(incorrectErrorCodeNumber);
         for (int i = 0; i < mMetrics.MAX_DHCP_ERROR_COUNT; i++) {
             mMetrics.addDhcpErrorCode(DhcpErrorEvent.PARSING_ERROR);
         }
         mStats = mMetrics.statsWrite();
-        assertEquals(DhcpErrorCode.ET_DHCP_ERROR, mStats.getDhcpSession().getErrorCode(0));
-        assertEquals(DhcpErrorCode.ET_L2_WRONG_ETH_TYPE, mStats.getDhcpSession().getErrorCode(1));
-        assertEquals(DhcpErrorCode.ET_L3_INVALID_IP, mStats.getDhcpSession().getErrorCode(2));
-        assertEquals(DhcpErrorCode.ET_L4_WRONG_PORT, mStats.getDhcpSession().getErrorCode(3));
-        assertEquals(DhcpErrorCode.ET_BOOTP_TOO_SHORT, mStats.getDhcpSession().getErrorCode(4));
-        assertEquals(DhcpErrorCode.ET_DHCP_NO_COOKIE, mStats.getDhcpSession().getErrorCode(5));
-        // Check can record the same error code
-        assertEquals(DhcpErrorCode.ET_PARSING_ERROR, mStats.getDhcpSession().getErrorCode(6));
-        assertEquals(DhcpErrorCode.ET_PARSING_ERROR, mStats.getDhcpSession().getErrorCode(6));
+        assertEquals(DhcpErrorCode.ET_BOOTP_TOO_SHORT, mStats.getDhcpSession().getErrorCode(0));
+        assertEquals(DhcpErrorCode.ET_BUFFER_UNDERFLOW, mStats.getDhcpSession().getErrorCode(1));
+        // When the input is an invalid integer value (such as incorrectErrorCodeNumber),
+        // the DhcpErrorCode will be ET_UNKNOWN
+        assertEquals(DhcpErrorCode.ET_UNKNOWN, mStats.getDhcpSession().getErrorCode(2));
+        // If the same error code appears, it must be recorded
+        assertEquals(DhcpErrorCode.ET_PARSING_ERROR, mStats.getDhcpSession().getErrorCode(3));
+        assertEquals(DhcpErrorCode.ET_PARSING_ERROR, mStats.getDhcpSession().getErrorCode(4));
         // The maximum number of DHCP error code counts is MAX_DHCP_ERROR_COUNT
         assertEquals(mMetrics.MAX_DHCP_ERROR_COUNT, mStats.getDhcpSession().getErrorCodeCount());
     }