Added characters that look like padlocks to URL unescaping blacklist.

net/base/escape.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/base/escape.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 146 matching lines @@
   if (!UnescapeUnsignedCharAtIndex(escaped_text, index + 6, &third_byte))
     return false;
   if (second_byte == 0x80) {
     return third_byte == 0x8E ||
            third_byte == 0x8F ||
            (third_byte >= 0xAA && third_byte <= 0xAE);
   }
   return third_byte >= 0xA6 && third_byte <= 0xA9;
 }
 
+// Returns true if there is a four-byte banned char at |index|. |first_byte| is
+// the byte at |index|.
+template <typename STR>
+bool HasFourByteBannedCharAtIndex(const STR& escaped_text,
+                                  unsigned char first_byte,
+                                  size_t index) {
+  // The following characters are blacklisted for spoofability concerns.
+  // U+1F50F LOCK WITH INK PEN         (%F0%9F%94%8F)
+  // U+1F510 CLOSED LOCK WITH KEY      (%F0%9F%94%90)
+  // U+1F512 LOCK                      (%F0%9F%94%92)
+  // U+1F513 OPEN LOCK                 (%F0%9F%94%93)
+  if (first_byte != 0xF0)
+    return false;
+
+  unsigned char second_byte;
+  if (!UnescapeUnsignedCharAtIndex(escaped_text, index + 3, &second_byte) ||
+      second_byte != 0x9F) {
+    return false;
+  }
+
+  unsigned char third_byte;
+  if (!UnescapeUnsignedCharAtIndex(escaped_text, index + 6, &third_byte) ||
+      third_byte != 0x94) {
+    return false;
+  }
+
+  unsigned char fourth_byte;
+  return UnescapeUnsignedCharAtIndex(escaped_text, index + 9, &fourth_byte) &&
+         (fourth_byte == 0x8F || fourth_byte == 0x90 || fourth_byte == 0x92 ||
+          fourth_byte == 0x93);
+}
+
 // Unescapes |escaped_text| according to |rules|, returning the resulting
 // string.  Fills in an |adjustments| parameter, if non-NULL, so it reflects
 // the alterations done to the string that are not one-character-to-one-
 // character.  The resulting |adjustments| will always be sorted by increasing
 // offset.
 template<typename STR>
 STR UnescapeURLWithAdjustmentsImpl(
     const STR& escaped_text,
     UnescapeRule::Type rules,
     base::OffsetAdjuster::Adjustments* adjustments) {
@@ skipping 33 matching lines @@
       // Additionally, the Unicode Technical Report (TR9) as referenced by RFC
       // 3987 above has since added some new BiDi control characters.
       // http://www.unicode.org/reports/tr9
       //
       // U+061C ARABIC LETTER MARK         (%D8%9C)
       // U+2066 LEFT-TO-RIGHT ISOLATE      (%E2%81%A6)
       // U+2067 RIGHT-TO-LEFT ISOLATE      (%E2%81%A7)
       // U+2068 FIRST STRONG ISOLATE       (%E2%81%A8)
       // U+2069 POP DIRECTIONAL ISOLATE    (%E2%81%A9)
       //
+      // The following spoofable characters are also banned, because they could
+      // be used to imitate parts of a web browser's UI.
+      //
+      // U+1F50F LOCK WITH INK PEN         (%F0%9F%94%8F)
+      // U+1F510 CLOSED LOCK WITH KEY      (%F0%9F%94%90)
+      // U+1F512 LOCK                      (%F0%9F%94%92)
+      // U+1F513 OPEN LOCK                 (%F0%9F%94%93)
+      //
       // However, some schemes such as data: and file: need to parse the exact
-      // binary data when loading the URL. For that reason, CONTROL_CHARS allows
-      // unescaping BiDi control characters.
-      // DO NOT use CONTROL_CHARS if the parsed URL is going to be displayed
-      // in the UI.
-      if (!(rules & UnescapeRule::CONTROL_CHARS)) {
+      // binary data when loading the URL. For that reason,
+      // SPOOFING_AND_CONTROL_CHARS allows unescaping BiDi control characters.
+      // DO NOT use SPOOFING_AND_CONTROL_CHARS if the parsed URL is going to be
+      // displayed in the UI.
+      if (!(rules & UnescapeRule::SPOOFING_AND_CONTROL_CHARS)) {
         if (HasArabicLanguageMarkAtIndex(escaped_text, first_byte, i)) {
           // Keep Arabic Language Mark escaped.
           result.append(escaped_text, i, 6);
           i += 5;
           continue;
         }
         if (HasThreeByteBidiControlCharAtIndex(escaped_text, first_byte, i)) {
           // Keep BiDi control char escaped.
           result.append(escaped_text, i, 9);
           i += 8;
           continue;
         }
+        if (HasFourByteBannedCharAtIndex(escaped_text, first_byte, i)) {
+          // Keep banned char escaped.
+          result.append(escaped_text, i, 12);
+          i += 11;
+          continue;
+        }
       }
 
       if (first_byte >= 0x80 ||  // Unescape all high-bit characters.
           // For 7-bit characters, the lookup table tells us all valid chars.
           (kUrlUnescape[first_byte] ||
            // ...and we allow some additional unescaping when flags are set.
            (first_byte == ' ' && (rules & UnescapeRule::SPACES)) ||
            // Allow any of the prohibited but non-control characters when
            // we're doing "special" chars.
            (first_byte > ' ' && (rules & UnescapeRule::URL_SPECIAL_CHARS)) ||
-           // Additionally allow control characters if requested.
-           (first_byte < ' ' && (rules & UnescapeRule::CONTROL_CHARS)))) {
+           // Additionally allow non-display characters if requested.
+           (first_byte < ' ' &&
+            (rules & UnescapeRule::SPOOFING_AND_CONTROL_CHARS)))) {
         // Use the unescaped version of the character.
         if (adjustments)
           adjustments->push_back(base::OffsetAdjuster::Adjustment(i, 3, 1));
         result.push_back(first_byte);
         i += 2;
       } else {
         // Keep escaped. Append a percent and we'll get the following two
         // digits on the next loops through.
         result.push_back('%');
       }
@@ skipping 194 matching lines @@
                        1, kEscapeToChars[i].replacement);
           break;
         }
       }
     }
   }
   return text;
 }
 
 }  // namespace net