Support replacement of IP address resolutions via command line flag

net/base/ip_pattern.h

+// Copyright (c) 2014 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.
+
+#ifndef NET_BASE_IP_PATTERN_H_
+#define NET_BASE_IP_PATTERN_H_
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/strings/string_piece.h"
+#include "net/base/net_export.h"
+#include "net/base/net_util.h"
+
+namespace net {
+
+// IPPatterns are used to match IP address resolutions for possible augmentation
+// by a MappedIPResolver, which uses IPMappingRules.
+class NET_EXPORT IPPattern {
+ public:
+  IPPattern();
+  ~IPPattern();
+
+  // Parse a textual pattern  (IP_PATTERN as defined in ip_mapping_rules.h) into
+  // |this| and return true if the parsing was successful.
+  bool ParsePattern(const std::string& ip_pattern);
+  // Test to see if the current pattern in |this| matches the given |address|
+  // and return true if it matches.
+  bool Match(const IPAddressNumber& address) const;
+
+  bool is_ipv4() const { return is_ipv4_; }
+
+ private:
+  class ComponentPattern;
+  typedef std::vector<std::string> Strings;
+  typedef std::vector<ComponentPattern*> ComponentPatternList;
+
+  // IPv6 addresses have 8 components, while IPv4 addresses have 4 components.
+  // ComponentPattern is used to define patterns to match individual components.
+  bool ParseComponentPattern(const base::StringPiece& text,
+                             ComponentPattern* pattern) const;
+  // Convert IP component to an int.  Assume hex vs decimal for IPV6 vs V4.
+  bool ValueTextToInt(const base::StringPiece& input, uint32* output) const;
+
+  bool is_ipv4_;
+  // The |ip_mask_| indicates, for each component, if this pattern requires an
+  // exact match (OCTET in IPv4, or 4 hex digits in IPv6).
+  // For each true element there is an entry in |component_values_|, and false
+  // means that an entry from our list of ComponentPattern instances must be
+  // applied.
+  std::vector<bool> ip_mask_;
+  // The vector of fixed values that are requried.
+  // Other values may be restricted by the component_patterns_;
+  // The class invariant is:
+  // ip_mask_.size() == component_patterns_.size()
+  //                    + size(our ComponentPattern list)
+  std::vector<uint32> component_values_;
+  // If only one component position was specified using a range, then this
+  // list will only have 1 element (i.e., we only have patterns for each element
+  // of ip_mask_ that is false.)
+  // We own these elements, and need to destroy them all when we are destroyed.
+  ComponentPatternList component_patterns_;
+
+  DISALLOW_COPY_AND_ASSIGN(IPPattern);
+};
+
+}  // namespace net
+
+#endif  // NET_BASE_IP_PATTERN_H_