The documentation in doc/gatt-api.txt specifies a number of flags that control the security of the operations.[0] These flags contain no documentation besides a reference to the Core Bluetooth Specification. Unfortunately, the Core Specification has now changed and the references no longer apply to the most recent documents. Further, even if the references were correct, the documentation is also rather opaque and presumes a lot of knowledge about Bluetooth to understand the actual properties. An application developer cannot be presumed to have this knowledge. Additionally, some of the flags (I think secure-read and secure-write) don't appear to have any corollary in the specification. Nor is it clear what behavior they actually implement. The combination of unclear documentation and critical security properties is compounded by the unclear relationship between the flags. For example, how should the following three flags be used together: write, authenticated-signed-writes, encrypt-authenticated-write? Does this mean that the unsigned writes, signed writes and signed-and-encrypted writes are allowed and any one of them may be chosen (leading to potential disclosure of sensitive information)? Or does it mean that writes are allowed if they are signed and encrypted? Would it be possible to get some clear documentation on not only how to use these flags but what security properties emerge from their use in various combinations? I would hate for security issues to arise because developers are using this API incorrectly. Thanks! [0]: https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/doc/gatt-api.txt#n227 -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
