1 // Copyright (c) 2011 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_DNS_QUERY_H_ 6 #define NET_DNS_DNS_QUERY_H_ 7 8 #include "base/basictypes.h" 9 #include "base/memory/ref_counted.h" 10 #include "base/strings/string_piece.h" 11 #include "net/base/net_export.h" 12 13 namespace net { 14 15 class IOBufferWithSize; 16 17 // Represents on-the-wire DNS query message as an object. 18 // TODO(szym): add support for the OPT pseudo-RR (EDNS0/DNSSEC). 19 class NET_EXPORT_PRIVATE DnsQuery { 20 public: 21 // Constructs a query message from |qname| which *MUST* be in a valid 22 // DNS name format, and |qtype|. The qclass is set to IN. 23 DnsQuery(uint16 id, const base::StringPiece& qname, uint16 qtype); 24 ~DnsQuery(); 25 26 // Clones |this| verbatim, with ID field of the header set to |id|. 27 DnsQuery* CloneWithNewId(uint16 id) const; 28 29 // DnsQuery field accessors. 30 uint16 id() const; 31 base::StringPiece qname() const; 32 uint16 qtype() const; 33 34 // Returns the Question section of the query. Used when matching the 35 // response. 36 base::StringPiece question() const; 37 38 // IOBuffer accessor to be used for writing out the query. io_buffer()39 IOBufferWithSize* io_buffer() const { return io_buffer_.get(); } 40 41 void set_flags(uint16 flags); 42 43 private: 44 DnsQuery(const DnsQuery& orig, uint16 id); 45 46 // Size of the DNS name (*NOT* hostname) we are trying to resolve; used 47 // to calculate offsets. 48 size_t qname_size_; 49 50 // Contains query bytes to be consumed by higher level Write() call. 51 scoped_refptr<IOBufferWithSize> io_buffer_; 52 53 DISALLOW_COPY_AND_ASSIGN(DnsQuery); 54 }; 55 56 } // namespace net 57 58 #endif // NET_DNS_DNS_QUERY_H_ 59