Line data    Source code

       1             : /*
       2             :  *
       3             :  *    Copyright (c) 2020 Project CHIP Authors
       4             :  *
       5             :  *    Licensed under the Apache License, Version 2.0 (the "License");
       6             :  *    you may not use this file except in compliance with the License.
       7             :  *    You may obtain a copy of the License at
       8             :  *
       9             :  *        http://www.apache.org/licenses/LICENSE-2.0
      10             :  *
      11             :  *    Unless required by applicable law or agreed to in writing, software
      12             :  *    distributed under the License is distributed on an "AS IS" BASIS,
      13             :  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      14             :  *    See the License for the specific language governing permissions and
      15             :  *    limitations under the License.
      16             :  */
      17             : 
      18             : #pragma once
      19             : 
      20             : #include <lib/dnssd/minimal_mdns/core/Constants.h>
      21             : #include <lib/dnssd/minimal_mdns/core/DnsHeader.h>
      22             : #include <lib/dnssd/minimal_mdns/core/QName.h>
      23             : #include <lib/dnssd/minimal_mdns/core/RecordWriter.h>
      24             : 
      25             : namespace mdns {
      26             : namespace Minimal {
      27             : 
      28             : class QueryData
      29             : {
      30             : public:
      31         120 :     QueryData() {}
      32             :     QueryData(const QueryData &)             = default;
      33             :     QueryData & operator=(const QueryData &) = default;
      34             : 
      35         114 :     QueryData(QType type, QClass klass, bool unicast) : mType(type), mClass(klass), mAnswerViaUnicast(unicast) {}
      36             : 
      37             :     QueryData(QType type, QClass klass, bool unicast, const uint8_t * nameStart, const BytesRange & validData) :
      38             :         mType(type), mClass(klass), mAnswerViaUnicast(unicast), mNameIterator(validData, nameStart)
      39             :     {}
      40             : 
      41        2737 :     QType GetType() const { return mType; }
      42        2988 :     QClass GetClass() const { return mClass; }
      43        1021 :     bool RequestedUnicastAnswer() const { return mAnswerViaUnicast; }
      44             : 
      45             :     /// Internal broadcasts will advertise all available data and will not apply
      46             :     /// any broadcast filtering. Intent is for paths such as:
      47             :     ///   - boot time advertisement: advertise all services available
      48             :     ///   - stop-time advertisement: advertise a TTL of 0 as services are removed
      49        1398 :     bool IsAnnounceBroadcast() const { return mIsAnnounceBroadcast; }
      50         114 :     void SetIsAnnounceBroadcast(bool isAnnounceBroadcast) { mIsAnnounceBroadcast = isAnnounceBroadcast; }
      51             : 
      52         430 :     SerializedQNameIterator GetName() const { return mNameIterator; }
      53             : 
      54             :     /// Parses a query structure
      55             :     ///
      56             :     /// Parses the query at [start] and updates start to the end of the structure.
      57             :     ///
      58             :     /// returns true on parse success, false on failure.
      59             :     bool Parse(const BytesRange & validData, const uint8_t ** start);
      60             : 
      61             :     /// Write out this query data back into an output buffer.
      62             :     bool Append(HeaderRef & hdr, RecordWriter & out) const;
      63             : 
      64             : private:
      65             :     QType mType            = QType::ANY;
      66             :     QClass mClass          = QClass::ANY;
      67             :     bool mAnswerViaUnicast = false;
      68             :     SerializedQNameIterator mNameIterator;
      69             : 
      70             :     /// Flag as an internal broadcast, controls reply construction (e.g. no
      71             :     /// filtering applied)
      72             :     bool mIsAnnounceBroadcast = false;
      73             : };
      74             : 
      75             : class ResourceData
      76             : {
      77             : public:
      78         120 :     ResourceData() {}
      79             : 
      80             :     ResourceData(const ResourceData &)             = default;
      81             :     ResourceData & operator=(const ResourceData &) = default;
      82             : 
      83        1161 :     QType GetType() const { return mType; }
      84             :     QClass GetClass() const { return mClass; }
      85             :     uint64_t GetTtlSeconds() const { return mTtl; }
      86         169 :     SerializedQNameIterator GetName() const { return mNameIterator; }
      87         160 :     const BytesRange & GetData() const { return mData; }
      88             : 
      89             :     /// Parses a resource data structure
      90             :     ///
      91             :     /// Parses the daata at [start] and updates start to the end of the structure.
      92             :     /// Updates [out] with the parsed data on success.
      93             :     ///
      94             :     /// returns true on parse success, false on failure.
      95             :     bool Parse(const BytesRange & validData, const uint8_t ** start);
      96             : 
      97             : private:
      98             :     SerializedQNameIterator mNameIterator;
      99             :     QType mType   = QType::ANY;
     100             :     QClass mClass = QClass::ANY;
     101             :     uint64_t mTtl = 0;
     102             :     BytesRange mData;
     103             : };
     104             : 
     105             : class ParserDelegate
     106             : {
     107             : public:
     108          30 :     virtual ~ParserDelegate() {}
     109             : 
     110             :     virtual void OnHeader(ConstHeaderRef & header) = 0;
     111             : 
     112             :     virtual void OnQuery(const QueryData & data) = 0;
     113             : 
     114             :     virtual void OnResource(ResourceType type, const ResourceData & data) = 0;
     115             : };
     116             : 
     117             : /// Parses a mMDNS packet.
     118             : ///
     119             : /// Calls appropriate delegate callbacks while parsing
     120             : ///
     121             : /// returns true if packet was successfully parsed, false otherwise
     122             : bool ParsePacket(const BytesRange & packetData, ParserDelegate * delegate);
     123             : 
     124             : } // namespace Minimal
     125             : } // namespace mdns