1 /*
2  * Copyright 2019 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <cstdint>
20 #include <queue>
21 #include <vector>
22 
23 #include "l2cap/cid.h"
24 #include "l2cap/internal/data_pipeline_manager.h"
25 #include "l2cap/internal/dynamic_channel_allocator.h"
26 #include "l2cap/l2cap_packets.h"
27 #include "l2cap/le/internal/dynamic_channel_service_manager_impl.h"
28 #include "l2cap/le/internal/fixed_channel_impl.h"
29 #include "l2cap/le/internal/fixed_channel_service_manager_impl.h"
30 #include "l2cap/mtu.h"
31 #include "l2cap/psm.h"
32 #include "l2cap/signal_id.h"
33 #include "os/alarm.h"
34 #include "os/handler.h"
35 #include "os/queue.h"
36 #include "packet/raw_builder.h"
37 
38 namespace bluetooth {
39 namespace l2cap {
40 namespace le {
41 namespace internal {
42 
43 struct PendingCommand {
44   SignalId signal_id_ = kInvalidSignalId;
45   LeCommandCode command_code_;
46   Psm psm_;
47   Cid source_cid_;
48   Cid destination_cid_;
49   Mtu mtu_;
50   uint16_t mps_;
51   uint16_t credits_;
52   uint16_t interval_min_;
53   uint16_t interval_max_;
54   uint16_t slave_latency_;
55   uint16_t timeout_multiplier_;
56 
CreditBasedConnectionRequestPendingCommand57   static PendingCommand CreditBasedConnectionRequest(SignalId signal_id, Psm psm, Cid scid, Mtu mtu, uint16_t mps,
58                                                      uint16_t initial_credits) {
59     PendingCommand pending_command;
60     pending_command.signal_id_ = signal_id;
61     pending_command.command_code_ = LeCommandCode::LE_CREDIT_BASED_CONNECTION_REQUEST;
62     pending_command.psm_ = psm;
63     pending_command.source_cid_ = scid;
64     pending_command.mtu_ = mtu;
65     pending_command.mps_ = mps;
66     pending_command.credits_ = initial_credits;
67     return pending_command;
68   }
69 
DisconnectionRequestPendingCommand70   static PendingCommand DisconnectionRequest(SignalId signal_id, Cid scid, Cid dcid) {
71     PendingCommand pending_command;
72     pending_command.signal_id_ = signal_id;
73     pending_command.command_code_ = LeCommandCode::DISCONNECTION_REQUEST;
74     pending_command.source_cid_ = scid;
75     pending_command.destination_cid_ = dcid;
76     return pending_command;
77   }
78 
ConnectionParameterUpdatePendingCommand79   static PendingCommand ConnectionParameterUpdate(SignalId signal_id, uint16_t interval_min, uint16_t interval_max,
80                                                   uint16_t slave_latency, uint16_t timeout_multiplier) {
81     PendingCommand pending_command;
82     pending_command.signal_id_ = signal_id;
83     pending_command.command_code_ = LeCommandCode::CONNECTION_PARAMETER_UPDATE_REQUEST;
84     pending_command.interval_min_ = interval_min;
85     pending_command.interval_max_ = interval_max;
86     pending_command.slave_latency_ = slave_latency;
87     pending_command.timeout_multiplier_ = timeout_multiplier;
88     return pending_command;
89   }
90 };
91 
92 class Link;
93 
94 class LeSignallingManager {
95  public:
96   LeSignallingManager(os::Handler* handler, Link* link, l2cap::internal::DataPipelineManager* data_pipeline_manager,
97                       DynamicChannelServiceManagerImpl* dynamic_service_manager,
98                       l2cap::internal::DynamicChannelAllocator* channel_allocator);
99 
100   virtual ~LeSignallingManager();
101 
102   void SendConnectionRequest(Psm psm, Cid local_cid, Mtu mtu);
103 
104   void SendDisconnectRequest(Cid local_cid, Cid remote_cid);
105 
106   // Note: Since Core 4.1, LL slave can send this through HCI command.
107   void SendConnectionParameterUpdateRequest(uint16_t interval_min, uint16_t interval_max, uint16_t slave_latency,
108                                             uint16_t timeout_multiplier);
109 
110   void SendConnectionParameterUpdateResponse(SignalId signal_id, ConnectionParameterUpdateResponseResult result);
111 
112   void SendCredit(Cid local_cid, uint16_t credits);
113 
114   void CancelAlarm();
115 
116   void OnCommandReject(LeCommandRejectView command_reject_view);
117 
118   void OnConnectionParameterUpdateRequest(SignalId signal_id, uint16_t interval_min, uint16_t interval_max,
119                                           uint16_t slave_latency, uint16_t timeout_multiplier);
120   void OnConnectionParameterUpdateResponse(SignalId signal_id, ConnectionParameterUpdateResponseResult result);
121 
122   void OnConnectionRequest(SignalId signal_id, Psm psm, Cid remote_cid, Mtu mtu, uint16_t mps,
123                            uint16_t initial_credits);
124 
125   void OnConnectionResponse(SignalId signal_id, Cid remote_cid, Mtu mtu, uint16_t mps, uint16_t initial_credits,
126                             LeCreditBasedConnectionResponseResult result);
127 
128   void OnDisconnectionRequest(SignalId signal_id, Cid cid, Cid remote_cid);
129 
130   void OnDisconnectionResponse(SignalId signal_id, Cid cid, Cid remote_cid);
131 
132   void OnCredit(Cid remote_cid, uint16_t credits);
133 
134  private:
135   struct PendingConnection {
136     Cid remote_cid;
137     Mtu mtu;
138     uint16_t max_pdu_size;
139     uint16_t initial_credits;
140     SignalId incoming_signal_id;
141   };
142 
143   void on_incoming_packet();
144   void send_connection_response(SignalId signal_id, Cid local_cid, Mtu mtu, uint16_t mps, uint16_t initial_credit,
145                                 LeCreditBasedConnectionResponseResult result);
146   void on_command_timeout();
147   void handle_send_next_command();
148   void on_security_result_for_incoming(Psm psm, PendingConnection request, bool result);
149   void on_security_result_for_outgoing(Psm psm, Cid local_cid, Mtu mtu, bool result);
150 
151   os::Handler* handler_;
152   Link* link_;
153   l2cap::internal::DataPipelineManager* data_pipeline_manager_;
154   std::shared_ptr<le::internal::FixedChannelImpl> signalling_channel_;
155   DynamicChannelServiceManagerImpl* dynamic_service_manager_;
156   l2cap::internal::DynamicChannelAllocator* channel_allocator_;
157   std::unique_ptr<os::EnqueueBuffer<packet::BasePacketBuilder>> enqueue_buffer_;
158   std::queue<PendingCommand> pending_commands_;
159   PendingCommand command_just_sent_;
160   os::Alarm alarm_;
161   SignalId next_signal_id_ = kInitialSignalId;
162 };
163 
164 }  // namespace internal
165 }  // namespace le
166 }  // namespace l2cap
167 }  // namespace bluetooth
168