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/internal/dynamic_channel_allocator.h"
22 #include "l2cap/internal/dynamic_channel_impl.h"
23 #include "l2cap/security_policy.h"
24 #include "os/log.h"
25
26 namespace bluetooth {
27 namespace l2cap {
28 namespace internal {
29
AllocateChannel(Psm psm,Cid remote_cid,SecurityPolicy security_policy)30 std::shared_ptr<DynamicChannelImpl> DynamicChannelAllocator::AllocateChannel(Psm psm, Cid remote_cid,
31 SecurityPolicy security_policy) {
32 ASSERT_LOG(IsPsmValid(psm), "Psm 0x%x is invalid", psm);
33
34 if (used_remote_cid_.find(remote_cid) != used_remote_cid_.end()) {
35 LOG_INFO("Remote cid 0x%x is used", remote_cid);
36 return nullptr;
37 }
38 Cid cid = kFirstDynamicChannel;
39 for (; cid <= kLastDynamicChannel; cid++) {
40 if (used_cid_.find(cid) == used_cid_.end()) break;
41 }
42 if (cid > kLastDynamicChannel) {
43 LOG_WARN("All cid are used");
44 return nullptr;
45 }
46 auto elem =
47 channels_.try_emplace(cid, std::make_shared<DynamicChannelImpl>(psm, cid, remote_cid, link_, l2cap_handler_));
48 ASSERT_LOG(elem.second, "Failed to create channel for psm 0x%x device %s", psm,
49 link_->GetDevice().ToString().c_str());
50 ASSERT(elem.first->second != nullptr);
51 used_remote_cid_.insert(remote_cid);
52 used_cid_.insert(cid);
53 return elem.first->second;
54 }
55
AllocateReservedChannel(Cid reserved_cid,Psm psm,Cid remote_cid,SecurityPolicy security_policy)56 std::shared_ptr<DynamicChannelImpl> DynamicChannelAllocator::AllocateReservedChannel(Cid reserved_cid, Psm psm,
57 Cid remote_cid,
58 SecurityPolicy security_policy) {
59 ASSERT_LOG(IsPsmValid(psm), "Psm 0x%x is invalid", psm);
60
61 if (used_remote_cid_.find(remote_cid) != used_remote_cid_.end()) {
62 LOG_INFO("Remote cid 0x%x is used", remote_cid);
63 return nullptr;
64 }
65 auto elem = channels_.try_emplace(
66 reserved_cid, std::make_shared<DynamicChannelImpl>(psm, reserved_cid, remote_cid, link_, l2cap_handler_));
67 ASSERT_LOG(elem.second, "Failed to create channel for psm 0x%x device %s", psm,
68 link_->GetDevice().ToString().c_str());
69 ASSERT(elem.first->second != nullptr);
70 used_remote_cid_.insert(remote_cid);
71 return elem.first->second;
72 }
73
ReserveChannel()74 Cid DynamicChannelAllocator::ReserveChannel() {
75 Cid cid = kFirstDynamicChannel;
76 for (; cid <= kLastDynamicChannel; cid++) {
77 if (used_cid_.find(cid) == used_cid_.end()) break;
78 }
79 if (cid > kLastDynamicChannel) {
80 LOG_WARN("All cid are used");
81 return kInvalidCid;
82 }
83 used_cid_.insert(cid);
84 return cid;
85 }
86
FreeChannel(Cid cid)87 void DynamicChannelAllocator::FreeChannel(Cid cid) {
88 used_cid_.erase(cid);
89 auto channel = FindChannelByCid(cid);
90 if (channel == nullptr) {
91 LOG_INFO("Channel is not in use: psm %d, device %s", cid, link_->GetDevice().ToString().c_str());
92 return;
93 }
94 used_remote_cid_.erase(channel->GetRemoteCid());
95 channels_.erase(cid);
96 }
97
IsPsmUsed(Psm psm) const98 bool DynamicChannelAllocator::IsPsmUsed(Psm psm) const {
99 for (const auto& channel : channels_) {
100 if (channel.second->GetPsm() == psm) {
101 return true;
102 }
103 }
104 return false;
105 }
106
FindChannelByCid(Cid cid)107 std::shared_ptr<DynamicChannelImpl> DynamicChannelAllocator::FindChannelByCid(Cid cid) {
108 if (channels_.find(cid) == channels_.end()) {
109 LOG_WARN("Can't find cid %d", cid);
110 return nullptr;
111 }
112 return channels_.find(cid)->second;
113 }
114
FindChannelByRemoteCid(Cid remote_cid)115 std::shared_ptr<DynamicChannelImpl> DynamicChannelAllocator::FindChannelByRemoteCid(Cid remote_cid) {
116 for (auto& channel : channels_) {
117 if (channel.second->GetRemoteCid() == remote_cid) {
118 return channel.second;
119 }
120 }
121 return nullptr;
122 }
123
NumberOfChannels() const124 size_t DynamicChannelAllocator::NumberOfChannels() const {
125 return channels_.size();
126 }
127
OnAclDisconnected(hci::ErrorCode reason)128 void DynamicChannelAllocator::OnAclDisconnected(hci::ErrorCode reason) {
129 for (auto& elem : channels_) {
130 elem.second->OnClosed(reason);
131 }
132 }
133
134 } // namespace internal
135 } // namespace l2cap
136 } // namespace bluetooth
137