src/connectivity/bluetooth/core/bt-host/l2cap/le_signaling_channel_unittest.cc

// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "le_signaling_channel.h"

#include "fake_channel_test.h"
#include "src/connectivity/bluetooth/core/bt-host/common/test_helpers.h"
#include "src/lib/fxl/arraysize.h"

namespace bt {
namespace l2cap {
namespace internal {
namespace {

constexpr hci::ConnectionHandle kTestHandle = 0x0001;
constexpr uint8_t kTestCmdId = 1;

template <hci::Connection::Role Role = hci::Connection::Role::kMaster>
class LESignalingChannelTest : public testing::FakeChannelTest {
 public:
  LESignalingChannelTest() = default;
  ~LESignalingChannelTest() override = default;

 protected:
  void SetUp() override {
    ChannelOptions options(kLESignalingChannelId);
    options.conn_handle = kTestHandle;

    auto fake_chan = CreateFakeChannel(options);
    sig_ = std::make_unique<LESignalingChannel>(std::move(fake_chan), Role);
  }

  void TearDown() override { sig_ = nullptr; }

  LESignalingChannel* sig() const { return sig_.get(); }

 private:
  std::unique_ptr<LESignalingChannel> sig_;

  DISALLOW_COPY_AND_ASSIGN_ALLOW_MOVE(LESignalingChannelTest);
};

using L2CAP_LESignalingChannelTest = LESignalingChannelTest<>;

using L2CAP_LESignalingChannelSlaveTest =
    LESignalingChannelTest<hci::Connection::Role::kSlave>;

TEST_F(L2CAP_LESignalingChannelTest, IgnoreEmptyFrame) {
  bool send_cb_called = false;
  auto send_cb = [&send_cb_called](auto) { send_cb_called = true; };

  fake_chan()->SetSendCallback(std::move(send_cb), dispatcher());
  fake_chan()->Receive(BufferView());

  RunLoopUntilIdle();
  EXPECT_FALSE(send_cb_called);
}

TEST_F(L2CAP_LESignalingChannelTest, RejectMalformedTooLarge) {
  // Command Reject packet.
  // clang-format off
  auto expected = CreateStaticByteBuffer(
      // Command header
      0x01, kTestCmdId, 0x02, 0x00,

      // Reason (Command not understood)
      0x00, 0x00);

  // Header-encoded length is less than the otherwise-valid Connection Parameter
  // Update packet's payload size.
  auto cmd_with_oversize_payload = CreateStaticByteBuffer(
      0x12, kTestCmdId, 0x07, 0x00,

      // Valid connection parameters
      0x06, 0x00,
      0x80, 0x0C,
      0xF3, 0x01,
      0x80, 0x0C);
  // clang-format on

  EXPECT_TRUE(ReceiveAndExpect(cmd_with_oversize_payload, expected));
}

TEST_F(L2CAP_LESignalingChannelTest, RejectMalformedTooSmall) {
  // Command Reject packet.
  // clang-format off
  auto expected = CreateStaticByteBuffer(
      // Command header
      0x01, kTestCmdId, 0x02, 0x00,

      // Reason (Command not understood)
      0x00, 0x00);

  // Header-encoded length is more than the otherwise-valid Connection Parameter
  // Update packet's payload size.
  auto cmd_with_undersize_payload = CreateStaticByteBuffer(
      0x12, kTestCmdId, 0x09, 0x00,

      // Valid connection parameters
      0x06, 0x00,
      0x80, 0x0C,
      0xF3, 0x01,
      0x80, 0x0C);
  // clang-format on

  EXPECT_TRUE(ReceiveAndExpect(cmd_with_undersize_payload, expected));
}

TEST_F(L2CAP_LESignalingChannelTest, DefaultMTU) {
  constexpr size_t kCommandSize = kMinLEMTU + 1;

  // The channel should start out with the minimum MTU as the default (23
  // octets).
  StaticByteBuffer<kCommandSize> cmd;

  // Make sure that the packet is well formed (the command code does not
  // matter).
  MutableSignalingPacket packet(&cmd, kCommandSize - sizeof(CommandHeader));
  packet.mutable_header()->id = kTestCmdId;
  packet.mutable_header()->length = htole16(packet.payload_size());

  // Command Reject packet.
  // clang-format off
  auto expected = CreateStaticByteBuffer(
      // Command header
      0x01, kTestCmdId, 0x04, 0x00,

      // Reason (Signaling MTU exceeded)
      0x01, 0x00,

      // The supported MTU (23)
      0x17, 0x00);
  // clang-format on

  EXPECT_TRUE(ReceiveAndExpect(cmd, expected));
}

TEST_F(L2CAP_LESignalingChannelTest, UnknownCommand) {
  // All unsupported commands must be rejected.
  const std::set<CommandCode> supported{kConnectionParameterUpdateRequest};
  for (CommandCode code = 0; code < std::numeric_limits<CommandCode>::max();
       code++) {
    // Skip supported commands as they are tested separately.
    if (supported.count(code))
      continue;

    // Use command code as ID.
    auto cmd = CreateStaticByteBuffer(code, code, 0x00, 0x00);

    // Expected
    // clang-format off
    auto expected = CreateStaticByteBuffer(
        // Command header
        0x01, code, 0x02, 0x00,

        // Reason (Command not understood)
        0x00, 0x00);
    // clang-format on

    ASSERT_TRUE(ReceiveAndExpect(cmd, expected));
  }
}

TEST_F(L2CAP_LESignalingChannelTest, ConnParamUpdateMalformedPayloadTooLarge) {
  // Packet size larger than conn. param. update payload.
  // clang-format off
  auto cmd = CreateStaticByteBuffer(
      0x12, kTestCmdId, 0x09, 0x00,

      // Valid conn. param. values:
      0x06, 0x00,
      0x80, 0x0C,
      0xF3, 0x01,
      0x0A, 0x00,

      // Extra byte
      0x00);

  auto expected = CreateStaticByteBuffer(
      // Command header
      0x01, kTestCmdId, 0x02, 0x00,

      // Reason (Command not understood)
      0x00, 0x00);
  // clang-format on

  EXPECT_TRUE(ReceiveAndExpect(cmd, expected));
}

TEST_F(L2CAP_LESignalingChannelTest, ConnParamUpdateMalformedPayloadTooSmall) {
  // Packet size larger than conn. param. update payload.
  // clang-format off
  auto cmd = CreateStaticByteBuffer(
      0x12, kTestCmdId, 0x07, 0x00,

      // Valid conn. param. values:
      0x06, 0x00,
      0x80, 0x0C,
      0xF3, 0x01,
      0x0A/*0x00 // Missing a byte */);

  auto expected = CreateStaticByteBuffer(
      // Command header
      0x01, kTestCmdId, 0x02, 0x00,

      // Reason (Command not understood)
      0x00, 0x00);
  // clang-format on

  EXPECT_TRUE(ReceiveAndExpect(cmd, expected));
}

TEST_F(L2CAP_LESignalingChannelTest, ConnParamUpdateReject) {
  // clang-format off
  StaticByteBuffer<12> commands[] = {
      CreateStaticByteBuffer(
          0x12, kTestCmdId, 0x08, 0x00,

          0x07, 0x00,  // interval min larger than max (both within range)
          0x06, 0x00,
          0xF3, 0x01,
          0x0A, 0x00),
      CreateStaticByteBuffer(
          0x12, kTestCmdId, 0x08, 0x00,

          0x05, 0x00,  // interval min too small
          0x80, 0x0C,
          0xF3, 0x01,
          0x0A, 0x00),
      CreateStaticByteBuffer(
          0x12, kTestCmdId, 0x08, 0x00,

          0x06, 0x00,
          0x81, 0x0C,  // interval max too large
          0xF3, 0x01,
          0x0A, 0x00),
      CreateStaticByteBuffer(
          0x12, kTestCmdId, 0x08, 0x00,

          0x06, 0x00,
          0x80, 0x0C,
          0xF4, 0x01,  // Latency too large
          0x0A, 0x00),
      CreateStaticByteBuffer(
          0x12, kTestCmdId, 0x08, 0x00,

          0x06, 0x00,
          0x80, 0x0C,
          0xF3, 0x01,
          0x09, 0x00), // Supv. timeout too small
      CreateStaticByteBuffer(
          0x12, kTestCmdId, 0x08, 0x00,

          0x06, 0x00,
          0x80, 0x0C,
          0xF3, 0x01,
          0x81, 0x0C)  // Supv. timeout too large
  };
  // clang-format on

  for (size_t i = 0; i < arraysize(commands); ++i) {
    // Conn. param. update response
    // clang-format off
    auto expected = CreateStaticByteBuffer(
        // Command header
        0x13, kTestCmdId, 0x02, 0x00,

        // Rejected
        0x01, 0x00);
    // clang-format on

    ASSERT_TRUE(ReceiveAndExpect(commands[i], expected));
  }
}

TEST_F(L2CAP_LESignalingChannelTest, ConnParamUpdateAccept) {
  // clang-format off
  auto cmd = CreateStaticByteBuffer(
      0x12, kTestCmdId, 0x08, 0x00,

      // Valid connection parameters
      0x06, 0x00,
      0x80, 0x0C,
      0xF3, 0x01,
      0x80, 0x0C);

  // Conn. param. update response
  auto expected = CreateStaticByteBuffer(
      // Command header
      0x13, kTestCmdId, 0x02, 0x00,

      // Accepted
      0x00, 0x00);
  // clang-format on

  bool fake_chan_cb_called = false;
  auto fake_chan_cb = [&expected, &fake_chan_cb_called](auto packet) {
    EXPECT_TRUE(ContainersEqual(expected, *packet));
    fake_chan_cb_called = true;
  };

  bool conn_param_cb_called = false;
  auto conn_param_cb = [&conn_param_cb_called](const auto& params) {
    EXPECT_EQ(0x0006, params.min_interval());
    EXPECT_EQ(0x0C80, params.max_interval());
    EXPECT_EQ(0x01F3, params.max_latency());
    EXPECT_EQ(0x0C80, params.supervision_timeout());
    conn_param_cb_called = true;
  };

  fake_chan()->SetSendCallback(fake_chan_cb, dispatcher());
  sig()->set_conn_param_update_callback(conn_param_cb, dispatcher());

  fake_chan()->Receive(cmd);

  RunLoopUntilIdle();

  EXPECT_TRUE(fake_chan_cb_called);
  EXPECT_TRUE(conn_param_cb_called);
}

TEST_F(L2CAP_LESignalingChannelSlaveTest, ConnParamUpdateReject) {
  // clang-format off
  auto cmd = CreateStaticByteBuffer(
      0x12, kTestCmdId, 0x08, 0x00,

      // Valid connection parameters
      0x06, 0x00,
      0x80, 0x0C,
      0xF3, 0x01,
      0x80, 0x0C);

  // Command rejected
  auto expected = CreateStaticByteBuffer(
      // Command header
      0x01, kTestCmdId, 0x02, 0x00,

      // Reason (Command not understood)
      0x00, 0x00);
  // clang-format on

  bool cb_called = false;
  auto cb = [&expected, &cb_called](auto packet) {
    EXPECT_TRUE(ContainersEqual(expected, *packet));
    cb_called = true;
  };

  fake_chan()->SetSendCallback(cb, dispatcher());
  fake_chan()->Receive(cmd);

  RunLoopUntilIdle();
  EXPECT_TRUE(cb_called);
}

}  // namespace
}  // namespace internal
}  // namespace l2cap
}  // namespace bt