Datasheet
“main” (Installation and Administration) — 2004/6/25 — 13:29 — page 350 — #376
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16.4.3 Configuration
The configuration files described in this section can only be modified by
the user root. Currently, there is no graphical user interface for setting the
parameters. Therefore, the files must be modified with a text editor.
A PIN number provides basic protection against unwanted connections.
Mobile phones usually query the PIN when establishing the first contact
(or when setting up a device contact on the phone). For two devices to be
able to communicate, both must identify themselves with the same PIN.
On the computer, the PIN is located in the file /etc/bluetooth/pin.
Currently, only one PIN is supported in Linux, regardless of the number of
installed Bluetooth devices. Because multiple devices cannot be addressed
with different PINs, set the same PIN on all devices or deactivate the PIN
authentication entirely.
Note
Security of Bluetooth Connections
Despite the PINs, the transmission between two devices may not
be entirely secure.
Note
/etc/bluetooth/hcid.conf is main configuration file for Linux Blue-
tooth. Various settings, such as the device names and the security modes,
can be modified in this file. Usually, the settings should be adequate. The
file contains comments describing the options for the various settings.
security auto; is one of the most important settings. If necessary, a PIN
is activated for the identification. If problems are encountered, the option
auto disables the PIN. Depending on your preferences and your security
needs, set this option to none never to use PIN numbers or to user to use
PIN numbers.
Another important section is the one beginning with device {. In this
section, define the name under which the host should be displayed on the
other side. The device class (Laptop, Server, etc.), authentication, and
encryption are defined in this section.
16.4.4 System Components and Useful Tools
The operability of Bluetooth depends on the interaction of various services.
At least two background daemons are needed: hcid (host controller inter-
face), which serves as an interface for the Bluetooth device and controls it,
350 16.4. Bluetooth — Wireless Connections