[Passpoint] Truncate IMSI from the SimCredential toString method

Truncate IMSI from the SimCredential toString method, avoid displaying
confidential IMSI information.

Bug: 149422812
Test: dumpsys wifi - confirm result
Change-Id: I9d542bc6ff60de1a78076abe1010c0c03a5f444b

1 files changed, 10 insertions, 1 deletions

diff --git a/wifi/java/android/net/wifi/hotspot2/pps/Credential.java b/wifi/java/android/net/wifi/hotspot2/pps/Credential.java
index 99901808ec3e..9c01d3643c19 100644
--- a/wifi/java/android/net/wifi/hotspot2/pps/Credential.java
+++ b/wifi/java/android/net/wifi/hotspot2/pps/Credential.java
@@ -738,7 +738,16 @@ public final class Credential implements Parcelable {
         @Override
         public String toString() {
             StringBuilder builder = new StringBuilder();
-            builder.append("IMSI: ").append(mImsi).append("\n");
+            String imsi;
+            if (mImsi != null) {
+                if (mImsi.length() > 6 && mImsi.charAt(6) != '*') {
+                    // Truncate the full IMSI from the log
+                    imsi = mImsi.substring(0, 6) + "****";
+                } else {
+                    imsi = mImsi;
+                }
+                builder.append("IMSI: ").append(imsi).append("\n");
+            }
             builder.append("EAPType: ").append(mEapType).append("\n");
             return builder.toString();
         }