1 // Copyright 2013 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.
5 #ifndef NET_DNS_MDNS_CLIENT_H_
6 #define NET_DNS_MDNS_CLIENT_H_
11 #include "base/callback.h"
12 #include "net/base/ip_endpoint.h"
13 #include "net/dns/dns_query.h"
14 #include "net/dns/dns_response.h"
15 #include "net/dns/record_parsed.h"
19 class DatagramServerSocket;
22 // Represents a one-time record lookup. A transaction takes one
23 // associated callback (see |MDnsClient::CreateTransaction|) and calls it
24 // whenever a matching record has been found, either from the cache or
25 // by querying the network (it may choose to query either or both based on its
26 // creation flags, see MDnsTransactionFlags). Network-based transactions will
27 // time out after a reasonable number of seconds.
28 class NET_EXPORT MDnsTransaction {
30 // Used to signify what type of result the transaction has recieved.
32 // Passed whenever a record is found.
34 // The transaction is done. Applies to non-single-valued transactions. Is
35 // called when the transaction has finished (this is the last call to the
38 // No results have been found. Applies to single-valued transactions. Is
39 // called when the transaction has finished without finding any results.
40 // For transactions that use the network, this happens when a timeout
41 // occurs, for transactions that are cache-only, this happens when no
42 // results are in the cache.
44 // Called when an NSec record is read for this transaction's
45 // query. This means there cannot possibly be a record of the type
46 // and name for this transaction.
50 // Used when creating an MDnsTransaction.
52 // Transaction should return only one result, and stop listening after it.
53 // Note that single result transactions will signal when their timeout is
54 // reached, whereas multi-result transactions will not.
55 SINGLE_RESULT = 1 << 0,
56 // Query the cache or the network. May both be used. One must be present.
58 QUERY_NETWORK = 1 << 2,
59 // TODO(noamsml): Add flag for flushing cache when feature is implemented
60 // Mask of all possible flags on MDnsTransaction.
61 FLAG_MASK = (1 << 3) - 1,
64 typedef base::Callback<void(Result, const RecordParsed*)>
67 // Destroying the transaction cancels it.
68 virtual ~MDnsTransaction() {}
70 // Start the transaction. Return true on success. Cache-based transactions
71 // will execute the callback synchronously.
72 virtual bool Start() = 0;
74 // Get the host or service name for the transaction.
75 virtual const std::string& GetName() const = 0;
77 // Get the type for this transaction (SRV, TXT, A, AAA, etc)
78 virtual uint16 GetType() const = 0;
81 // A listener listens for updates regarding a specific record or set of records.
82 // Created by the MDnsClient (see |MDnsClient::CreateListener|) and used to keep
83 // track of listeners.
84 class NET_EXPORT MDnsListener {
86 // Used in the MDnsListener delegate to signify what type of change has been
96 virtual ~Delegate() {}
98 // Called when a record is added, removed or updated.
99 virtual void OnRecordUpdate(UpdateType update,
100 const RecordParsed* record) = 0;
102 // Called when a record is marked nonexistent by an NSEC record.
103 virtual void OnNsecRecord(const std::string& name, unsigned type) = 0;
105 // Called when the cache is purged (due, for example, ot the network
107 virtual void OnCachePurged() = 0;
110 // Destroying the listener stops listening.
111 virtual ~MDnsListener() {}
113 // Start the listener. Return true on success.
114 virtual bool Start() = 0;
116 // Get the host or service name for this query.
117 // Return an empty string for no name.
118 virtual const std::string& GetName() const = 0;
120 // Get the type for this query (SRV, TXT, A, AAA, etc)
121 virtual uint16 GetType() const = 0;
124 // Creates bound datagram sockets ready to use by MDnsClient.
125 class NET_EXPORT MDnsSocketFactory {
127 virtual ~MDnsSocketFactory() {}
128 virtual void CreateSockets(ScopedVector<DatagramServerSocket>* sockets) = 0;
130 static scoped_ptr<MDnsSocketFactory> CreateDefault();
133 // Listens for Multicast DNS on the local network. You can access information
134 // regarding multicast DNS either by creating an |MDnsListener| to be notified
135 // of new records, or by creating an |MDnsTransaction| to look up the value of a
136 // specific records. When all listeners and active transactions are destroyed,
137 // the client stops listening on the network and destroys the cache.
138 class NET_EXPORT MDnsClient {
140 virtual ~MDnsClient() {}
142 // Create listener object for RRType |rrtype| and name |name|.
143 virtual scoped_ptr<MDnsListener> CreateListener(
145 const std::string& name,
146 MDnsListener::Delegate* delegate) = 0;
148 // Create a transaction that can be used to query either the MDns cache, the
149 // network, or both for records of type |rrtype| and name |name|. |flags| is
150 // defined by MDnsTransactionFlags.
151 virtual scoped_ptr<MDnsTransaction> CreateTransaction(
153 const std::string& name,
155 const MDnsTransaction::ResultCallback& callback) = 0;
157 virtual bool StartListening(MDnsSocketFactory* factory) = 0;
159 // Do not call this inside callbacks from related MDnsListener and
160 // MDnsTransaction objects.
161 virtual void StopListening() = 0;
162 virtual bool IsListening() const = 0;
164 // Create the default MDnsClient
165 static scoped_ptr<MDnsClient> CreateDefault();
168 NET_EXPORT IPEndPoint GetMDnsIPEndPoint(AddressFamily address_family);
170 typedef std::vector<std::pair<uint32, AddressFamily> > InterfaceIndexFamilyList;
171 // Returns pairs of interface and address family to bind. Current
172 // implementation returns unique list of all available interfaces.
173 NET_EXPORT InterfaceIndexFamilyList GetMDnsInterfacesToBind();
175 // Create sockets, binds socket to MDns endpoint, and sets multicast interface
176 // and joins multicast group on for |interface_index|.
177 // Returns NULL if failed.
178 NET_EXPORT scoped_ptr<DatagramServerSocket> CreateAndBindMDnsSocket(
179 AddressFamily address_family,
180 uint32 interface_index);
184 #endif // NET_DNS_MDNS_CLIENT_H_