I'm working with BlueZ 3.x. I have a linux embedded device and I need to send and receive files using the bluetooth technology, with Obex. (Note: BlueZ 4.x doesn't even compile on our specific platform.)
I don't need PIN authentication, I even don't want it. It must remain as simple as possible for the end user.
I tried to set security none in hcid.conf but it doesn't seem to work.
So my question is:
Is it possible to send &/ receive files using Obex on bluetooth?
How to do it?
Does bluetooth devices (e.g. mobile phone) requires authentication?
You can use the OBEX protocoll for that, but you will also need the FTP or OPP profile (And GOEP, SPP & GAP since they depend on them)
The documentation can be found on BT SIG bluetooth.org, but you will have to be a member. I think some of the documentation is available to non members as well, go there and have a look.
Yes (if we are only talking about mobile phones)
Related
I am doing some research on the WebUSB API for our company because we are going to start to manufacture devices in house.
Our current device manufacture comes with an application so the team can plug the device into a computer and diagnose it. Their application allows us to read outputs from the device, as well as pushing commands/configuration to the device over a wired connection.
Since this device is 100% ours, we are also responsible for building out the diagnostic tooling. We need some sort of interface that allows a user to read outputs and send commands/configuration to the device over a wired USB connection.
Is the webUSB the correct API? If not, what are some suggestions for accomplishing the requirement? Are we limited to building some sort of desktop or mobile application?
I would recommend resources below to read to help you understand if the WebUSB API fits your needs or not:
https://web.dev/devices-introduction/ helps you pick the appropriate API to communicate with a hardware device of your choice.
https://web.dev/build-for-webusb/ explains how to build a device to take full advantage of the WebUSB API.
From what you describe, WebUSB isn't strictly required but won't hurt either.
First and foremost, you will need to implement the USB interfaces reading data and sending configurations. It will be a custom protocol, and not one of the standard USB device classes such as HID, video or mass storage. The details of the protocol and if you use control, interrupt or bulk transfers is your choice.
I'm assuming you will connect the devices to Windows PCs, and you likely don't want to put money into writing device drivers. If so, the easiest approach is to add the required descriptors and control requests required for Microsoft OS 2.0 Descriptors. That way, the WinUSB driver will be installed automatically when the device is plugged in.
Using the WinUSB API, a Windows application will then be able to communicate with the USB device. No additional drivers are needed. (On macOS and Linux it's even easier as you don't need the Microsoft OS 2.0 Descriptors in the first place.)
On top of that you can implement the additional descriptors and control requests for WebUSB. It will provide the additional benefit that you can write a web application (instead of a native application) for communicating with the USB device. (Currently, you are restricted to the Chrome browser.) WebUSB devices should implement the WinUSB descriptors as the alternative (.INF files, manual installation process) is a pain.
The already mentioned web page https://web.dev/build-for-webusb/ is a complete example of how to implement it.
I am trying to make it so that my ESP32 board can detect my phone when I approach it based on RSSI. However, the ESP32 cannot see the phone unless the phone is in discovery mode, which is not super useful. To solve this, I was hoping to pair my phone with the ESP32 so that the phone would always be looking for the ESP32, and connect when it is found without any human intervention.
I decided to try the Arduino integration, but as I was working through all of the examples I couldn't find any with this functionality, so I'm kind of lost. If this is not possible or easy with Arduino, I am willing to switch, but I was unable to find anything about pairing in the normal phone interface for ESP-IDF either.
So, basically, using an ESP32, how do I pair to a phone?
The easiest way is to make the esp a gatt server and advertise a specific service. The phone will look for that specific service and connects if found.
You could make an app for your phone, like for ios its pretty easy. But keep in mind for mobile devices a continuous search for devices could be power unfriendly if misused.
If you use esp-idf instead of arduino, some examples are included. (You could use the vscode integrated esp-idd) Check learnesp32.com for an easy step into the basics, coming from Arduino.
I implemented the org.bluez.Agent1 interface using QDbus and I would like to set a fixed pin (that I will provide to the users) in order to authenticate all the pairing request and reject them if the pin is wrong. The agent capabilities should be "NoInputNoOutput" because the project will be deployed on the RaspberryPi 3 without keyboard or display. Is there a way to deal with this? Thank you
You should not initialize the capability as "NoInputOutput" for fixed key pairing. NoInputOutput means there is not display and there is no keyboard/UI possible for this device. Mentioning this capability for your Agent when registering with BlueZ means, instructing BlueZ (bluetoothd) not to call any Agent API for authentication.
This is typically useful to autopair without any manual intervention. You can see this sample code, which uses NoInputOutput capability to connect the device without any intervention.
What you need is "DisplayOnly" capability to instruct BlueZ to call "DisplayPinCode" or "DisplayPasskey" based on SSP support of your device.
You can implement DisplayPinCode/DisplayPasskey in your Agent to reply constant PIN always. So the Bluetooth device which tries to connect can use the same constant PIN for pairing.
Here Display Pin /Passkey is just the naming convention or hint to Agent developers to write wizard/UI or any form of display operations. But you can completely ignore the displaying operation and reply with static/constant 6 digit key for pairing.
Typically this Agent API is called by Bluez (in rasperry pi) when the device (iPhone/Android mobile/any bluetooth capable device) trying pair calls "RequestPasskey" or "RequestPinCode" from the device end.
We had the same issue in a project, and i moved on LE device do to the fact that apple device are only capable to connect to LE device for "safety" reasons.
I don't have that much ref to that but if this could help you in your researches.
I need to connect to a Bluetooth device through virtual COM port created in Windows. It's easy when the port has been already created during manual pairing procedure. But I would like my application to relieve an user from the manual pairing of a device. I would like to present all devices in the range, allow user to chose one, and then create virtual COM port connected with the selected device. I'm not trying to avoid the pairing procedure itself, but rather I would like to invoke it by my application.
I started getting familiar with Microsoft Bluetooth API. And then some doubts arose. I've been wondering what happen if some user would use different (than Microsoft's) Bluetooth stack? Is the Microsoft's API the real Bluetooth API, which have to be implemented by any other Bluetooth stack provider? Or rather each provider has its own API, and the Microsoft's is only one of many other?
Thanks everyone for valuable input. I'd like to summarize what I've found so far. The Microsoft Bluetooth API is not operating system API. Application written against it will not cooperate correctly with any other Bluetooth stack. It seems that applications which are intended to cooperate with multiple stacks need to provide some stack abstraction layer, and stack specific code for all of them.The other solution is to allow user for manual pairing of the Bluetooth device, which eventually create some virtual device in the operating system (e.g., COM port). Then the application can use standard interface of such a device.
I can't speak for the Microsoft Bluetooth API, but there are multiple Bluetooth stacks available for the PC platform (even more for mobile devices).
The underlying API is defined by the Bluetooth Core Spec and so all stacks should be able to interact, in fact it is mandatory that they interop or they cannot use the Bluetooth name and logo.
As to pairing, your going to have a hard time getting devices to pair if they have default security, which requires a pin code.
Things might be simpler in the (near) future, as the Bluetooth standard has introduced a new security model, secure simple pairing, which has a 'just works' mode that requires no Pin code. This is still stronger then the current security, except against Man in the middle attacks. However, it could be a while before you see the chips with this feature in PCs.
If you can change to using .NET :-/ I can recommend our library 32feet.NET.
For explicit pairing there's BluetoothSecurity.PairDevice. We can also create the virtual port for you, for example:
BluetoothClient cli = new BluetoothClient();
BluetoothDeviceInfo[] list = cli.DiscoverDevices();
BluetoothDeviceInfo selected = GetUserToSelectOne(list);
BluetoothSecurity.PairDevice(selected, pin);
// Ask Win32 to create a virtual serial port
selected.SetServiceState(BluetoothService.SerialPort);
However I really don't like virtual serial ports so I always suggest that people use a normal sockets connection using our BluetoothClient class, it will automatically handle a pairing request if required.
On Win32 we support the stacks from Microsoft, Widcomm/Broadcom, and BlueSoleil. On Widcomm there's no support for SetServiceState there yet, and their API has no support for responding to pairing requests. BlueSoleil should support both.
A brief user's guide is at 32feet.NET — User’s Guide, and all the class documentation is available at the main site http://32feet.net, the Widcomm documentation is only in our code repository at the moment.
I want to send almost 4k size data to any cellphone by using bluetooth.
Firstly to do this, I need to find what stacks are in my phone and what stacks are acting when I send a data.
I really struggle to find the way; however, it is really hard.
If you know how to find it, please give me some information!!
See http://32feet.NET if you are talking about Windows Mobile. It is a managed library for Bluetooth, OBEX, and IrDA. We support both the Microsoft stack, but also have support for Widcomm. And now also Bluesoleil and Stonestreet One Bluetopia.
You can either send and receive the data as an OBEX message, or over a simple bluetooth connection. See a copy of the user's guide at http://www.alanjmcf.me.uk/comms/bluetooth/32feet.NET%20—%20User’s%20Guide.html
Goto "https://www.bluetooth.org/tpg/listings.cfm" type the name of your mobile. This will give you information on the Bluetooth stack inside and the profiles supported.