From 3ef9db42aba814e95313ad2a5d0c5e36f2801efe Mon Sep 17 00:00:00 2001
From: M66B <M66B@users.noreply.github.com>
Date: Fri, 28 Jun 2019 17:06:13 +0200
Subject: [PATCH] Better link sanitization

---
 FAQ.md                                        |   1 -
 .../eu/faircode/email/AdapterMessage.java     | 111 +++++++++++++-----
 app/src/main/res/layout/dialog_open_link.xml  |  18 ++-
 app/src/main/res/values/strings.xml           |   5 +-
 4 files changed, 98 insertions(+), 37 deletions(-)

diff --git a/FAQ.md b/FAQ.md
index aec09a36ec..20475dd45e 100644
--- a/FAQ.md
+++ b/FAQ.md
@@ -1543,7 +1543,6 @@ The advanced option *extra privacy features* enables:
 
 * Looking up the owner of the IP address of a link
 * Detection and removal of [tracking images](#user-content-faq82)
-* Removal of [Urchin Tracking Module (UTM) parameters](https://en.wikipedia.org/wiki/UTM_parameters) from links
 
 <br />
 
diff --git a/app/src/main/java/eu/faircode/email/AdapterMessage.java b/app/src/main/java/eu/faircode/email/AdapterMessage.java
index accb584c26..e8f80f3f28 100644
--- a/app/src/main/java/eu/faircode/email/AdapterMessage.java
+++ b/app/src/main/java/eu/faircode/email/AdapterMessage.java
@@ -44,12 +44,14 @@ import android.os.Bundle;
 import android.os.Handler;
 import android.provider.ContactsContract;
 import android.provider.Settings;
+import android.text.Editable;
 import android.text.Html;
 import android.text.Layout;
 import android.text.Spannable;
 import android.text.SpannableStringBuilder;
 import android.text.Spanned;
 import android.text.TextUtils;
+import android.text.TextWatcher;
 import android.text.method.ArrowKeyMovementMethod;
 import android.text.style.DynamicDrawableSpan;
 import android.text.style.ImageSpan;
@@ -2211,56 +2213,105 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                 final SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
                 boolean paranoid = prefs.getBoolean("paranoid", true);
 
-                final Uri _uri;
-                if (paranoid && !uri.isOpaque()) {
+                final Uri sanitized;
+                if (uri.isOpaque())
+                    sanitized = uri;
+                else {
                     // https://en.wikipedia.org/wiki/UTM_parameters
-                    Uri.Builder builder = new Uri.Builder();
-
-                    String scheme = uri.getScheme();
-                    if (!TextUtils.isEmpty(scheme))
-                        builder.scheme(scheme);
-
-                    String authority = uri.getEncodedAuthority();
-                    if (!TextUtils.isEmpty(authority))
-                        builder.encodedAuthority(authority);
-
-                    String path = uri.getEncodedPath();
-                    if (!TextUtils.isEmpty(path))
-                        builder.encodedPath(path);
+                    Uri.Builder builder = uri.buildUpon();
 
+                    builder.clearQuery();
                     for (String key : uri.getQueryParameterNames())
                         if (!PARANOID_QUERY.contains(key.toLowerCase()))
                             for (String value : uri.getQueryParameters(key))
-                                builder.appendQueryParameter(key, value);
-
-                    String fragment = uri.getEncodedFragment();
-                    if (!TextUtils.isEmpty(fragment))
-                        builder.encodedFragment(fragment);
-
-                    _uri = builder.build();
+                                if (!TextUtils.isEmpty(key)) {
+                                    Log.i("Query " + key + "=" + value);
+                                    builder.appendQueryParameter(key, value);
+                                }
 
-                    Log.i("Source uri=" + uri);
-                    Log.i("Target uri=" + _uri);
-                } else
-                    _uri = uri;
+                    sanitized = builder.build();
+                }
 
                 View view = LayoutInflater.from(context).inflate(R.layout.dialog_open_link, null);
                 TextView tvTitle = view.findViewById(R.id.tvTitle);
                 final EditText etLink = view.findViewById(R.id.etLink);
-                TextView tvInsecure = view.findViewById(R.id.tvInsecure);
+                final CheckBox cbSecure = view.findViewById(R.id.cbSecure);
+                CheckBox cbSanitize = view.findViewById(R.id.cbSanitize);
                 final TextView tvOwner = view.findViewById(R.id.tvOwner);
                 final Group grpOwner = view.findViewById(R.id.grpOwner);
 
                 tvTitle.setText(title);
                 tvTitle.setVisibility(TextUtils.isEmpty(title) ? View.GONE : View.VISIBLE);
 
-                etLink.setText(_uri.toString());
-                tvInsecure.setVisibility("http".equals(_uri.getScheme()) ? View.VISIBLE : View.GONE);
+                cbSecure.setVisibility(View.GONE);
+                etLink.addTextChangedListener(new TextWatcher() {
+                    @Override
+                    public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
+                    }
+
+                    @Override
+                    public void onTextChanged(CharSequence text, int i, int i1, int i2) {
+                    }
+
+                    @Override
+                    public void afterTextChanged(Editable text) {
+                        Uri uri = Uri.parse(text.toString());
+                        cbSecure.setVisibility(!uri.isOpaque() &&
+                                ("http".equals(uri.getScheme()) || "https".equals(uri.getScheme()))
+                                ? View.VISIBLE : View.GONE);
+                    }
+                });
+                etLink.setText(uri.toString());
+
+                boolean secure = "https".equals(uri.getScheme());
+                cbSecure.setChecked(secure);
+                cbSecure.setText(
+                        secure ? R.string.title_link_secured : R.string.title_secure_link);
+                cbSecure.setTextColor(Helper.resolveColor(context,
+                        secure ? android.R.attr.textColorSecondary : R.attr.colorWarning));
+                cbSecure.setTypeface(
+                        secure ? Typeface.DEFAULT : Typeface.DEFAULT_BOLD);
+                cbSecure.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
+                    @Override
+                    public void onCheckedChanged(CompoundButton compoundButton, boolean checked) {
+                        Uri uri = Uri.parse(etLink.getText().toString());
+                        Uri.Builder builder = uri.buildUpon();
+
+                        builder.scheme(checked ? "https" : "http");
+
+                        String authority = uri.getEncodedAuthority();
+                        if (authority != null) {
+                            authority = authority.replace(checked ? ":80" : ":443", checked ? ":443" : ":80");
+                            builder.encodedAuthority(authority);
+                        }
+
+                        etLink.setText(builder.build().toString());
+
+                        cbSecure.setText(
+                                checked ? R.string.title_link_secured : R.string.title_secure_link);
+                        cbSecure.setTextColor(Helper.resolveColor(context,
+                                checked ? android.R.attr.textColorSecondary : R.attr.colorWarning));
+                        cbSecure.setTypeface(
+                                checked ? Typeface.DEFAULT : Typeface.DEFAULT_BOLD);
+                    }
+                });
+
+                cbSanitize.setVisibility(uri.equals(sanitized) ? View.GONE : View.VISIBLE);
+                cbSanitize.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
+                    @Override
+                    public void onCheckedChanged(CompoundButton compoundButton, boolean checked) {
+                        if (checked)
+                            etLink.setText(sanitized.toString());
+                        else
+                            etLink.setText(uri.toString());
+                    }
+                });
+
                 grpOwner.setVisibility(View.GONE);
 
                 if (paranoid) {
                     Bundle args = new Bundle();
-                    args.putParcelable("uri", _uri);
+                    args.putParcelable("uri", uri);
 
                     new SimpleTask<String>() {
                         @Override
diff --git a/app/src/main/res/layout/dialog_open_link.xml b/app/src/main/res/layout/dialog_open_link.xml
index 16ee9bf38b..dd4e19945d 100644
--- a/app/src/main/res/layout/dialog_open_link.xml
+++ b/app/src/main/res/layout/dialog_open_link.xml
@@ -39,18 +39,26 @@
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toBottomOf="@id/tvTitle" />
 
-    <TextView
-        android:id="@+id/tvInsecure"
+    <CheckBox
+        android:id="@+id/cbSecure"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginTop="12dp"
-        android:text="@string/title_insecure_link"
-        android:textAppearance="@style/TextAppearance.AppCompat.Small"
+        android:text="@string/title_secure_link"
         android:textColor="?attr/colorWarning"
         android:textStyle="bold"
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toBottomOf="@id/etLink" />
 
+    <CheckBox
+        android:id="@+id/cbSanitize"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="12dp"
+        android:text="@string/title_sanitize_link"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@id/cbSecure" />
+
     <TextView
         android:id="@+id/tvOwnerTitle"
         android:layout_width="wrap_content"
@@ -60,7 +68,7 @@
         android:text="@string/title_ip_owner"
         android:textAppearance="@style/TextAppearance.AppCompat.Small"
         app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toBottomOf="@id/tvInsecure" />
+        app:layout_constraintTop_toBottomOf="@id/cbSanitize" />
 
     <TextView
         android:id="@+id/tvOwner"
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index cae00a1b1e..be44d4f0ab 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -692,8 +692,11 @@
     <string name="title_hint_ignore_contact">Long press a contact to never consider it as a favorite</string>
 
     <string name="title_open_link">Open link</string>
-    <string name="title_ip_owner">Owner IP address</string>
+    <string name="title_secure_link">Make link secure</string>
+    <string name="title_link_secured">Link is secure</string>
+    <string name="title_sanitize_link">Remove tracking parameters</string>
     <string name="title_insecure_link">This link is insecure</string>
+    <string name="title_ip_owner">Owner IP address</string>
     <string name="title_select_app">Select app</string>
     <string name="title_updated">There is an update to version %1$s available</string>
     <string name="title_issue">Do you have a question or problem?</string>