1 /*
2  * Copyright 2018 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 <chrono>
20 #include <cstdint>
21 
22 #include "hci/address_with_type.h"
23 #include "packets/hci_packets.h"
24 #include "phy.h"
25 
26 namespace rootcanal {
27 
28 using ::bluetooth::hci::AddressWithType;
29 
30 enum AclConnectionState {
31   kActiveMode,
32   kHoldMode,
33   kSniffMode,
34 };
35 
36 // Model the connection of a device to the controller.
37 class AclConnection {
38  public:
39   AclConnection(AddressWithType address, AddressWithType own_address,
40                 AddressWithType resolved_address, Phy::Type phy_type,
41                 bluetooth::hci::Role role);
42 
43   virtual ~AclConnection() = default;
44 
GetPhyType()45   Phy::Type GetPhyType() const { return type_; }
46 
GetAddress()47   AddressWithType GetAddress() const { return address_; }
GetOwnAddress()48   AddressWithType GetOwnAddress() const { return own_address_; }
GetResolvedAddress()49   AddressWithType GetResolvedAddress() const { return resolved_address_; }
50 
51   void Encrypt();
52   bool IsEncrypted() const;
53 
54   void SetLinkPolicySettings(uint16_t settings);
GetLinkPolicySettings()55   uint16_t GetLinkPolicySettings() const { return link_policy_settings_; }
IsRoleSwitchEnabled()56   bool IsRoleSwitchEnabled() const {
57     return (link_policy_settings_ & 0x1) != 0;
58   }
IsHoldModeEnabled()59   bool IsHoldModeEnabled() const { return (link_policy_settings_ & 0x2) != 0; }
IsSniffModeEnabled()60   bool IsSniffModeEnabled() const { return (link_policy_settings_ & 0x4) != 0; }
61 
GetMode()62   AclConnectionState GetMode() const { return state_; }
63 
64   bluetooth::hci::Role GetRole() const;
65   void SetRole(bluetooth::hci::Role role);
66 
67   int8_t GetRssi() const;
68   void SetRssi(int8_t rssi);
69 
70   std::chrono::steady_clock::duration TimeUntilNearExpiring() const;
71   std::chrono::steady_clock::duration TimeUntilExpired() const;
72   void ResetLinkTimer();
73   bool IsNearExpiring() const;
74   bool HasExpired() const;
75 
76   // LE-ACL state.
InitiatePhyUpdate()77   void InitiatePhyUpdate() { initiated_phy_update_ = true; }
PhyUpdateComplete()78   void PhyUpdateComplete() { initiated_phy_update_ = false; }
InitiatedPhyUpdate()79   bool InitiatedPhyUpdate() const { return initiated_phy_update_; }
GetTxPhy()80   bluetooth::hci::PhyType GetTxPhy() const { return tx_phy_; }
GetRxPhy()81   bluetooth::hci::PhyType GetRxPhy() const { return rx_phy_; }
SetTxPhy(bluetooth::hci::PhyType phy)82   void SetTxPhy(bluetooth::hci::PhyType phy) { tx_phy_ = phy; }
SetRxPhy(bluetooth::hci::PhyType phy)83   void SetRxPhy(bluetooth::hci::PhyType phy) { rx_phy_ = phy; }
84 
85  private:
86   AddressWithType address_;
87   AddressWithType own_address_;
88   AddressWithType resolved_address_;
89   Phy::Type type_{Phy::Type::BR_EDR};
90 
91   // Reports the RSSI measured for the last packet received on
92   // this connection.
93   int8_t rssi_{0};
94 
95   // State variables
96   bool encrypted_{false};
97   uint16_t link_policy_settings_{0};
98   AclConnectionState state_{kActiveMode};
99   bluetooth::hci::Role role_{bluetooth::hci::Role::CENTRAL};
100   std::chrono::steady_clock::time_point last_packet_timestamp_;
101   std::chrono::steady_clock::duration timeout_;
102 
103   // LE-ACL state.
104   bluetooth::hci::PhyType tx_phy_{bluetooth::hci::PhyType::LE_1M};
105   bluetooth::hci::PhyType rx_phy_{bluetooth::hci::PhyType::LE_1M};
106   bool initiated_phy_update_{false};
107 };
108 
109 }  // namespace rootcanal
110