Add ability to log last 2 digits of dialed numbers in userdebug builds.

Filers of bugs often refer to specific phone numbers.  Bug reports by
default obscure dialed phone numbers from the Telecom logs.  This makes it
difficult to relate events in the bug report to what the bug filer refers
to.

To ease this, in userdebug builds we will now leave the last 2 digits of
dialed phone numbers un-obfuscated.  User builds will remain obfuscated.

Test: Added unit tests to cover this case.
Bug: 78457192
Change-Id: I52704cf57ed11b1fa53a55bc883d7d090af661f4

1 files changed, 27 insertions, 1 deletions

diff --git a/telecomm/java/android/telecom/Log.java b/telecomm/java/android/telecom/Log.java
index 83ca4702287d..0eb991777d74 100644
--- a/telecomm/java/android/telecom/Log.java
+++ b/telecomm/java/android/telecom/Log.java
@@ -46,6 +46,11 @@ public class Log {
     private static final int EVENTS_TO_CACHE = 10;
     private static final int EVENTS_TO_CACHE_DEBUG = 20;
 
+    /**
+     * When generating a bug report, include the last X dialable digits when logging phone numbers.
+     */
+    private static final int NUM_DIALABLE_DIGITS_TO_LOG = Build.IS_USER ? 0 : 2;
+
     // Generic tag for all Telecom logging
     @VisibleForTesting
     public static String TAG = "TelecomFramework";
@@ -384,9 +389,15 @@ public class Log {
 
             String textToObfuscate = uri.getSchemeSpecificPart();
             if (PhoneAccount.SCHEME_TEL.equals(scheme)) {
+                int numDigitsToObfuscate = getDialableCount(textToObfuscate)
+                        - NUM_DIALABLE_DIGITS_TO_LOG;
                 for (int i = 0; i < textToObfuscate.length(); i++) {
                     char c = textToObfuscate.charAt(i);
-                    sb.append(PhoneNumberUtils.isDialable(c) ? "*" : c);
+                    boolean isDialable = PhoneNumberUtils.isDialable(c);
+                    if (isDialable) {
+                        numDigitsToObfuscate--;
+                    }
+                    sb.append(isDialable && numDigitsToObfuscate >= 0 ? "*" : c);
                 }
             } else if (PhoneAccount.SCHEME_SIP.equals(scheme)) {
                 for (int i = 0; i < textToObfuscate.length(); i++) {
@@ -405,6 +416,21 @@ public class Log {
     }
 
     /**
+     * Determines the number of dialable characters in a string.
+     * @param toCount The string to count dialable characters in.
+     * @return The count of dialable characters.
+     */
+    private static int getDialableCount(String toCount) {
+        int numDialable = 0;
+        for (char c : toCount.toCharArray()) {
+            if (PhoneNumberUtils.isDialable(c)) {
+                numDialable++;
+            }
+        }
+        return numDialable;
+    }
+
+    /**
      * Redact personally identifiable information for production users.
      * If we are running in verbose mode, return the original string,
      * and return "***" otherwise.