From ce7064982527865ee63c8fd136fe2cca52fbdb10 Mon Sep 17 00:00:00 2001
From: Jinsuk Kim <jinsukkim@chromium.org>
Date: Thu, 06 Feb 2025 13:38:45 -0800
Subject: [PATCH] [CCT] Suppress preview page for data: url on CCT

The volume of data: url scheme opening preview page on CCT
is pretty low. This CL suppresses the menu item as it could
present a potential security problem.

Histogram/enum added for the stats were also removed as they
were for one-off measurement.

Bug: 362545037
Change-Id: I72b6cf77507157b8f8dfdac43dee127530c9415a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6184388
Reviewed-by: Sinan Sahin <sinansahin@google.com>
Commit-Queue: Jinsuk Kim <jinsukkim@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1416995}
---

diff --git a/chrome/android/java/src/org/chromium/chrome/browser/contextmenu/ChromeContextMenuPopulator.java b/chrome/android/java/src/org/chromium/chrome/browser/contextmenu/ChromeContextMenuPopulator.java
index 5809857..86c45512 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/contextmenu/ChromeContextMenuPopulator.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/contextmenu/ChromeContextMenuPopulator.java
@@ -26,7 +26,6 @@
 
 import org.chromium.base.Callback;
 import org.chromium.base.ContextUtils;
-import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.shared_preferences.SharedPreferencesManager;
 import org.chromium.base.supplier.Supplier;
 import org.chromium.chrome.R;
@@ -211,67 +210,6 @@
         }
     }
 
-    // Used to record the UMA histogram Android.CustomTabs.ContextMenu.UrlScheme. These don't
-    // need to be a comprehensive list of schemes since what we are interested in is the relative
-    // volume of data scheme.
-    // Since these values are persisted to logs, they should never be renumbered or reused.
-    // LINT.IfChange(UrlScheme)
-    @VisibleForTesting
-    @IntDef({
-        UrlScheme.UNKNOWN_SCHEME,
-        UrlScheme.HTTP_SCHEME,
-        UrlScheme.HTTPS_SCHEME,
-        UrlScheme.FILE_SCHEME,
-        UrlScheme.FTP_SCHEME,
-        UrlScheme.DATA_SCHEME,
-        UrlScheme.JAVASCRIPT_SCHEME,
-        UrlScheme.CHROME_SCHEME,
-        UrlScheme.BLOB_SCHEME,
-        UrlScheme.CONTENT_SCHEME,
-        UrlScheme.INTENT_SCHEME,
-    })
-    public @interface UrlScheme {
-        int UNKNOWN_SCHEME = 0;
-        int HTTP_SCHEME = 1;
-        int HTTPS_SCHEME = 2;
-        int FILE_SCHEME = 3;
-        int FTP_SCHEME = 4;
-        int DATA_SCHEME = 5;
-        int JAVASCRIPT_SCHEME = 6;
-        int CHROME_SCHEME = 7;
-        int BLOB_SCHEME = 8;
-        int CONTENT_SCHEME = 9;
-        int INTENT_SCHEME = 10;
-        int COUNT = 11;
-    }
-
-    // LINT.ThenChange(/tools/metrics/histograms/metadata/custom_tabs/enums.xml:CustomTabsUrlScheme)
-
-    private static @UrlScheme int schemeForUrl(String scheme) {
-        if (scheme.equals(UrlConstants.HTTP_SCHEME)) {
-            return UrlScheme.HTTP_SCHEME;
-        } else if (scheme.equals(UrlConstants.HTTPS_SCHEME)) {
-            return UrlScheme.HTTPS_SCHEME;
-        } else if (scheme.equals(UrlConstants.FILE_SCHEME)) {
-            return UrlScheme.FILE_SCHEME;
-        } else if (scheme.equals(UrlConstants.FTP_SCHEME)) {
-            return UrlScheme.FTP_SCHEME;
-        } else if (scheme.equals(UrlConstants.DATA_SCHEME)) {
-            return UrlScheme.DATA_SCHEME;
-        } else if (scheme.equals(UrlConstants.JAVASCRIPT_SCHEME)) {
-            return UrlScheme.JAVASCRIPT_SCHEME;
-        } else if (scheme.equals(UrlConstants.CHROME_SCHEME)) {
-            return UrlScheme.CHROME_SCHEME;
-        } else if (scheme.equals(UrlConstants.BLOB_SCHEME)) {
-            return UrlScheme.BLOB_SCHEME;
-        } else if (scheme.equals(UrlConstants.CONTENT_SCHEME)) {
-            return UrlScheme.CONTENT_SCHEME;
-        } else if (scheme.equals(UrlConstants.INTENT_SCHEME)) {
-            return UrlScheme.INTENT_SCHEME;
-        }
-        return UrlScheme.UNKNOWN_SCHEME;
-    }
-
     /**
      * Builds a {@link ChromeContextMenuPopulator}.
      *
@@ -350,15 +288,15 @@
                 }
                 if ((mMode == ContextMenuMode.NORMAL || mMode == ContextMenuMode.CUSTOM_TAB)
                         && EphemeralTabCoordinator.isSupported()) {
-                    mShowEphemeralTabNewLabel = shouldTriggerEphemeralTabHelpUi();
-                    if (mMode == ContextMenuMode.CUSTOM_TAB) {
-                        @UrlScheme int enumScheme = schemeForUrl(mParams.getUrl().getScheme());
-                        RecordHistogram.recordEnumeratedHistogram(
-                                "CustomTabs.ContextMenu.UrlScheme", enumScheme, UrlScheme.COUNT);
+                    boolean showNewLabel = shouldTriggerEphemeralTabHelpUi();
+                    boolean isDataUrl =
+                            mParams.getUrl().getScheme().equals(UrlConstants.DATA_SCHEME);
+                    if (!(mMode == ContextMenuMode.CUSTOM_TAB && isDataUrl)) {
+                        // Do not show the item if CCT opens data: url as it could potentially
+                        // cause a security issue.
+                        linkGroup.add(createListItem(Item.OPEN_IN_EPHEMERAL_TAB, showNewLabel));
+                        mShowEphemeralTabNewLabel = showNewLabel;
                     }
-
-                    linkGroup.add(
-                            createListItem(Item.OPEN_IN_EPHEMERAL_TAB, mShowEphemeralTabNewLabel));
                 }
             }
             if (!MailTo.isMailTo(mParams.getLinkUrl().getSpec())
diff --git a/tools/metrics/histograms/metadata/custom_tabs/enums.xml b/tools/metrics/histograms/metadata/custom_tabs/enums.xml
index bcf6192..0676ac3 100644
--- a/tools/metrics/histograms/metadata/custom_tabs/enums.xml
+++ b/tools/metrics/histograms/metadata/custom_tabs/enums.xml
@@ -184,24 +184,6 @@
              memory"/>
 </enum>
 
-<!-- LINT.IfChange(CustomTabsUrlScheme) -->
-
-<enum name="CustomTabsUrlScheme">
-  <int value="0" label="Unknown scheme"/>
-  <int value="1" label="HTTP"/>
-  <int value="2" label="HTTPS"/>
-  <int value="3" label="File"/>
-  <int value="4" label="Ftp"/>
-  <int value="5" label="Data"/>
-  <int value="6" label="Javascript"/>
-  <int value="7" label="Chrome"/>
-  <int value="8" label="Blob"/>
-  <int value="9" label="Content"/>
-  <int value="10" label="Intent"/>
-</enum>
-
-<!-- LINT.ThenChange(//chrome/android/java/src/org/chromium/chrome/browser/contextmenu/ChromeContextMenuPopulator.java:UrlScheme) -->
-
 <enum name="GoogleBottomBarButtonEvent">
   <int value="0" label="Unknown button"/>
   <int value="1" label="Chrome Page Insights button"/>
diff --git a/tools/metrics/histograms/metadata/custom_tabs/histograms.xml b/tools/metrics/histograms/metadata/custom_tabs/histograms.xml
index 999cd33d..8d30595e7 100644
--- a/tools/metrics/histograms/metadata/custom_tabs/histograms.xml
+++ b/tools/metrics/histograms/metadata/custom_tabs/histograms.xml
@@ -227,18 +227,6 @@
   </summary>
 </histogram>
 
-<histogram name="CustomTabs.ContextMenu.UrlScheme" enum="CustomTabsUrlScheme"
-    expires_after="2025-07-27">
-  <owner>jinsukkim@chromium.org</owner>
-  <owner>chrome-connective-tissue@google.com</owner>
-  <summary>
-    Records the scheme of the URL for which the context menu is shown on Custom
-    Tabs. This histogram is to understand the relative volume of data: scheme
-    with a view to not displaying the menu 'Preview Page' for the scheme if the
-    volume is insignificant. Recorded when the context menu is opened.
-  </summary>
-</histogram>
-
 <histogram base="true" name="CustomTabs.DetachedResourceRequest.Duration"
     units="ms" expires_after="2024-03-17">
   <owner>lizeb@chromium.org</owner>