Add UMAs for checking header values against RFC 7230 in //net

net/http/http_util.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.
 
 // The rules for parsing content-types were borrowed from Firefox:
 // http://lxr.mozilla.org/mozilla/source/netwerk/base/src/nsURLHelper.cpp#834
 
 #include "net/http/http_util.h"
 
 #include <algorithm>
@@ skipping 326 matching lines @@
 }
 
 // static
 bool HttpUtil::IsValidHeaderValue(const std::string& value) {
   // Just a sanity check: disallow NUL and CRLF.
   return value.find('\0') == std::string::npos &&
       value.find("\r\n") == std::string::npos;
 }
 
 // static
+bool HttpUtil::IsValidHeaderValueRFC7230(const base::StringPiece& value) {
+  // This empty string is a valid header-value.
+  if (value.empty())
+    return true;
+
+  // Check leading/trailing whitespaces.
+  if (IsLWS(value[0]) || IsLWS(value[value.size() - 1]))
+    return false;
+
+  // Check each octet is |field-vchar|, |SP| or |HTAB|.
+  for (unsigned char c : value) {
+    if (c == 0x7F || (c < 0x20 && c != '\t'))
+      return false;
+  }
+  return true;
+}
+
+// static
 std::string HttpUtil::StripHeaders(const std::string& headers,
                                    const char* const headers_to_remove[],
                                    size_t headers_to_remove_len) {
   std::string stripped_headers;
   HttpUtil::HeadersIterator it(headers.begin(), headers.end(), "\r\n");
 
   while (it.GetNext()) {
     bool should_remove = false;
     for (size_t i = 0; i < headers_to_remove_len; ++i) {
       if (base::LowerCaseEqualsASCII(
@@ skipping 582 matching lines @@
       value_is_quoted_ = true;
       // Do not store iterators into this. See declaration of unquoted_value_.
       unquoted_value_ = HttpUtil::Unquote(value_begin_, value_end_);
     }
   }
 
   return true;
 }
 
 }  // namespace net