1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef NET_DNS_MAPPED_HOST_RESOLVER_H_ 6 #define NET_DNS_MAPPED_HOST_RESOLVER_H_ 7 8 #include <string> 9 10 #include "base/memory/scoped_ptr.h" 11 #include "net/base/host_mapping_rules.h" 12 #include "net/base/net_export.h" 13 #include "net/dns/host_resolver.h" 14 15 namespace net { 16 17 // This class wraps an existing HostResolver instance, but modifies the 18 // request before passing it off to |impl|. This is different from 19 // MockHostResolver which does the remapping at the HostResolverProc 20 // layer, so it is able to preserve the effectiveness of the cache. 21 class NET_EXPORT MappedHostResolver : public HostResolver { 22 public: 23 // Creates a MappedHostResolver that forwards all of its requests through 24 // |impl|. 25 explicit MappedHostResolver(scoped_ptr<HostResolver> impl); 26 virtual ~MappedHostResolver(); 27 28 // Adds a rule to this mapper. The format of the rule can be one of: 29 // 30 // "MAP" <hostname_pattern> <replacement_host> [":" <replacement_port>] 31 // "EXCLUDE" <hostname_pattern> 32 // 33 // The <replacement_host> can be either a hostname, or an IP address literal, 34 // or "~NOTFOUND". If it is "~NOTFOUND" then all matched hostnames will fail 35 // to be resolved with ERR_NAME_NOT_RESOLVED. 36 // 37 // Returns true if the rule was successfully parsed and added. 38 bool AddRuleFromString(const std::string& rule_string) { 39 return rules_.AddRuleFromString(rule_string); 40 } 41 42 // Takes a comma separated list of rules, and assigns them to this resolver. 43 void SetRulesFromString(const std::string& rules_string) { 44 rules_.SetRulesFromString(rules_string); 45 } 46 47 // HostResolver methods: 48 virtual int Resolve(const RequestInfo& info, 49 RequestPriority priority, 50 AddressList* addresses, 51 const CompletionCallback& callback, 52 RequestHandle* out_req, 53 const BoundNetLog& net_log) OVERRIDE; 54 virtual int ResolveFromCache(const RequestInfo& info, 55 AddressList* addresses, 56 const BoundNetLog& net_log) OVERRIDE; 57 virtual void CancelRequest(RequestHandle req) OVERRIDE; 58 virtual void SetDnsClientEnabled(bool enabled) OVERRIDE; 59 virtual HostCache* GetHostCache() OVERRIDE; 60 virtual base::Value* GetDnsConfigAsValue() const OVERRIDE; 61 62 private: 63 // Modify the request |info| according to |rules_|. Returns either OK or 64 // the network error code that the hostname's resolution mapped to. 65 int ApplyRules(RequestInfo* info) const; 66 67 scoped_ptr<HostResolver> impl_; 68 69 HostMappingRules rules_; 70 }; 71 72 } // namespace net 73 74 #endif // NET_DNS_MAPPED_HOST_RESOLVER_H_ 75