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 #include <unordered_map>
18
19 #include "l2cap/cid.h"
20 #include "l2cap/classic/internal/link.h"
21 #include "l2cap/classic/security_policy.h"
22 #include "l2cap/internal/dynamic_channel_allocator.h"
23 #include "l2cap/internal/dynamic_channel_impl.h"
24 #include "os/log.h"
25
26 namespace bluetooth {
27 namespace l2cap {
28 namespace internal {
29
AllocateChannel(Psm psm,Cid remote_cid)30 std::shared_ptr<DynamicChannelImpl> DynamicChannelAllocator::AllocateChannel(Psm psm, Cid remote_cid) {
31 ASSERT_LOG(IsPsmValid(psm), "Psm 0x%x is invalid", psm);
32
33 if (used_remote_cid_.find(remote_cid) != used_remote_cid_.end()) {
34 LOG_INFO("Remote cid 0x%x is used", remote_cid);
35 return nullptr;
36 }
37 Cid cid = kFirstDynamicChannel;
38 for (; cid <= kLastDynamicChannel; cid++) {
39 if (used_cid_.find(cid) == used_cid_.end()) break;
40 }
41 if (cid > kLastDynamicChannel) {
42 LOG_WARN("All cid are used");
43 return nullptr;
44 }
45 auto elem =
46 channels_.try_emplace(cid, std::make_shared<DynamicChannelImpl>(psm, cid, remote_cid, link_, l2cap_handler_));
47 ASSERT_LOG(elem.second, "Failed to create channel for psm 0x%x device %s", psm,
48 link_->GetDevice().ToString().c_str());
49 ASSERT(elem.first->second != nullptr);
50 used_remote_cid_.insert(remote_cid);
51 used_cid_.insert(cid);
52 return elem.first->second;
53 }
54
AllocateReservedChannel(Cid reserved_cid,Psm psm,Cid remote_cid)55 std::shared_ptr<DynamicChannelImpl> DynamicChannelAllocator::AllocateReservedChannel(Cid reserved_cid, Psm psm,
56 Cid remote_cid) {
57 ASSERT_LOG(IsPsmValid(psm), "Psm 0x%x is invalid", psm);
58
59 if (used_remote_cid_.find(remote_cid) != used_remote_cid_.end()) {
60 LOG_INFO("Remote cid 0x%x is used", remote_cid);
61 return nullptr;
62 }
63 auto elem = channels_.try_emplace(
64 reserved_cid, std::make_shared<DynamicChannelImpl>(psm, reserved_cid, remote_cid, link_, l2cap_handler_));
65 ASSERT_LOG(elem.second, "Failed to create channel for psm 0x%x device %s", psm,
66 link_->GetDevice().ToString().c_str());
67 ASSERT(elem.first->second != nullptr);
68 used_remote_cid_.insert(remote_cid);
69 return elem.first->second;
70 }
71
ReserveChannel()72 Cid DynamicChannelAllocator::ReserveChannel() {
73 Cid cid = kFirstDynamicChannel;
74 for (; cid <= kLastDynamicChannel; cid++) {
75 if (used_cid_.find(cid) == used_cid_.end()) break;
76 }
77 if (cid > kLastDynamicChannel) {
78 LOG_WARN("All cid are used");
79 return kInvalidCid;
80 }
81 used_cid_.insert(cid);
82 return cid;
83 }
84
FreeChannel(Cid cid)85 void DynamicChannelAllocator::FreeChannel(Cid cid) {
86 used_cid_.erase(cid);
87 auto channel = FindChannelByCid(cid);
88 if (channel == nullptr) {
89 LOG_INFO("Channel is not in use: psm %d, device %s", cid, link_->GetDevice().ToString().c_str());
90 return;
91 }
92 used_remote_cid_.erase(channel->GetRemoteCid());
93 channels_.erase(cid);
94 }
95
IsPsmUsed(Psm psm) const96 bool DynamicChannelAllocator::IsPsmUsed(Psm psm) const {
97 for (const auto& channel : channels_) {
98 if (channel.second->GetPsm() == psm) {
99 return true;
100 }
101 }
102 return false;
103 }
104
FindChannelByCid(Cid cid)105 std::shared_ptr<DynamicChannelImpl> DynamicChannelAllocator::FindChannelByCid(Cid cid) {
106 if (channels_.find(cid) == channels_.end()) {
107 LOG_WARN("Can't find cid %d", cid);
108 return nullptr;
109 }
110 return channels_.find(cid)->second;
111 }
112
FindChannelByRemoteCid(Cid remote_cid)113 std::shared_ptr<DynamicChannelImpl> DynamicChannelAllocator::FindChannelByRemoteCid(Cid remote_cid) {
114 for (auto& channel : channels_) {
115 if (channel.second->GetRemoteCid() == remote_cid) {
116 return channel.second;
117 }
118 }
119 return nullptr;
120 }
121
NumberOfChannels() const122 size_t DynamicChannelAllocator::NumberOfChannels() const {
123 return channels_.size();
124 }
125
OnAclDisconnected(hci::ErrorCode reason)126 void DynamicChannelAllocator::OnAclDisconnected(hci::ErrorCode reason) {
127 for (auto& elem : channels_) {
128 elem.second->OnClosed(reason);
129 }
130 }
131
132 } // namespace internal
133 } // namespace l2cap
134 } // namespace bluetooth
135