linux.git/net/bluetooth/Kconfig, branch master

Bluetooth: fix BT dependency for submodules

2026-08-07T19:38:30+00:00

The modules rfcomm (BT_RFCOMM), bnep (BT_BNEP), hidp (BT_HIDP), and
bluetooth_6lowpan (BT_6LOWPAN) are dependent on the bluetooth module
(BT, tristate) only transitively through the boolean BT_BREDR for the
first three and through the boolean BT_LE for the bluetooth_6lowpan.
Therefore, the modules can be selected as built-in even if the BT=m.
The combination of BT=m and =y for the said modules leads to the kernel
build system silently ignoring those modules, without ever compiling
them as built-in or as loadable modules.

Add BT as a direct dependency to the Kconfig of rfcomm, bnep, hidp, and
bluetooth_6lowpan. The modules set to =y when BT=m will default to =m,
rather then getting silently ignored by the build system.

Signed-off-by: Iva Kasprzaková 
Signed-off-by: Luiz Augusto von Dentz

Bluetooth: SMP: Use AES-CMAC library API

2026-06-11T18:24:38+00:00

Now that AES-CMAC has a library API, convert net/bluetooth/smp.c to use
it instead of the "cmac(aes)" crypto_shash.  Since the library API
doesn't require dynamic memory allocation, we no longer need to pass a
crypto_shash object down the call stack and can simply allocate the
aes_cmac_key on the stack in smp_aes_cmac() (renamed from aes_cmac()).

The result is simpler and faster code that no longer relies on the
error-prone loading of algorithms by name.

Note that the maximum stack usage actually decreases slightly, despite
the expanded AES key being moved to the stack.  This is because the old
code called crypto_shash_tfm_digest(), which allocates 384 bytes on the
stack for a maximally-sized hash descriptor for any algorithm.  The new
code instead declares a 288-byte aes_cmac_key, then calls aes_cmac()
which declares a 32-byte aes_cmac_ctx.  Since 288 + 32 < 384, the
maximum stack usage decreases.  I.e. the entire expanded AES key easily
fits in the space that the generic crypto API was wasting before.

I didn't add zeroization of the aes_cmac_key, since smp_aes_cmac()
already copies the raw key to the stack without zeroizing it.

Reviewed-by: Ard Biesheuvel 
Signed-off-by: Eric Biggers 
Signed-off-by: Luiz Augusto von Dentz

Bluetooth: Remove unneeded crypto kconfig selections

2026-06-11T18:24:38+00:00

Remove several kconfig selections that are no longer needed:

  - CRYPTO_SKCIPHER and CRYPTO_ECB have been unneeded since
    commit a4770e1117f1 ("Bluetooth: Switch SMP to
    crypto_cipher_encrypt_one()") in 2016.

  - CRYPTO_SHA256 has been unneeded since
    commit e7b02296fb40 ("Bluetooth: Remove BT_HS") in 2024.

Signed-off-by: Eric Biggers 
Signed-off-by: Luiz Augusto von Dentz

net: remove ISDN subsystem and Bluetooth CMTP

2026-04-23T17:24:02+00:00

Remove the ISDN (mISDN, CAPI) subsystem and Bluetooth CMTP protocol
from the kernel tree.

ISDN is a pretty old technology and it's unclear whether anyone still
uses it. I went over the last few years of git history and all the
commits are either tree-wide conversions or syzbot/static analyzer
fixes.

When we discussed removal in the past IIRC there were some concerns
about ISDN still being used in parts of Germany. Unfortunately, the
code base is quite old, none of the current maintainers are familiar
with it and AI tools will have a field day finding bugs here.

Delete this code and preserve it in an out-of-tree repository
for any remaining users:
https://github.com/linux-netdev/mod-orphan

UAPI constants AF_ISDN/PF_ISDN and the SELinux isdn_socket class
are preserved for ABI stability, but the rest of uAPI is removed.

Signed-off-by: Jakub Kicinski 
Acked-by: Greg Kroah-Hartman 
Acked-by: Stephen Hemminger 
Acked-by: Luiz Augusto von Dentz 
Reviewed-by: Simon Horman 
Link: https://patch.msgid.link/20260421022108.1299678-1-kuba@kernel.org
Signed-off-by: Paolo Abeni

Bluetooth: Remove BT_HS

2024-03-06T22:22:39+00:00

High Speed, Alternate MAC and PHY (AMP) extension, has been removed from
Bluetooth Core specification on 5.3:

https://www.bluetooth.com/blog/new-core-specification-v5-3-feature-enhancements/

Fixes: 244bc377591c ("Bluetooth: Add BT_HS config option")
Signed-off-by: Luiz Augusto von Dentz

Bluetooth: Add CONFIG_BT_LE_L2CAP_ECRED

2022-12-12T22:19:24+00:00

This adds CONFIG_BT_LE_L2CAP_ECRED which can be used to enable L2CAP
Enhanced Credit Flow Control Mode by default, previously it was only
possible to set it via module parameter (e.g. bluetooth.enable_ecred=1).

Since L2CAP ECRED mode is required by the likes of EATT which is
recommended for LE Audio this enables it by default.

Signed-off-by: Luiz Augusto von Dentz 
Tested-By: Tedd Ho-Jeong An

Bluetooth: Add initial implementation of CIS connections

2022-07-23T00:13:22+00:00

This adds the initial implementation of CIS connections and introduces
the ISO packets/links.

== Central: Set CIG Parameters, create a CIS and Setup Data Path ==

> tools/isotest -s 

< HCI Command: LE Extended Create... (0x08|0x0043) plen 26
...
> HCI Event: Command Status (0x0f) plen 4
      LE Extended Create Connection (0x08|0x0043) ncmd 1
        Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 31
      LE Enhanced Connection Complete (0x0a)
      ...
< HCI Command: LE Create Connected... (0x08|0x0064) plen 5
...
> HCI Event: Command Status (0x0f) plen 4
      LE Create Connected Isochronous Stream (0x08|0x0064) ncmd 1
        Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 29
      LE Connected Isochronous Stream Established (0x19)
      ...
< HCI Command: LE Setup Isochronou.. (0x08|0x006e) plen 13
...
> HCI Event: Command Complete (0x0e) plen 6
      LE Setup Isochronous Data Path (0x08|0x006e) ncmd 1
        Status: Success (0x00)
        Handle: 257
< HCI Command: LE Setup Isochronou.. (0x08|0x006e) plen 13
...
> HCI Event: Command Complete (0x0e) plen 6
      LE Setup Isochronous Data Path (0x08|0x006e) ncmd 1
        Status: Success (0x00)
        Handle: 257

== Peripheral: Accept CIS and Setup Data Path ==

> tools/isotest -d

 HCI Event: LE Meta Event (0x3e) plen 7
      LE Connected Isochronous Stream Request (0x1a)
...
< HCI Command: LE Accept Co.. (0x08|0x0066) plen 2
...
> HCI Event: LE Meta Event (0x3e) plen 29
      LE Connected Isochronous Stream Established (0x19)
...
< HCI Command: LE Setup Is.. (0x08|0x006e) plen 13
...
> HCI Event: Command Complete (0x0e) plen 6
      LE Setup Isochronous Data Path (0x08|0x006e) ncmd 1
        Status: Success (0x00)
        Handle: 257
< HCI Command: LE Setup Is.. (0x08|0x006e) plen 13
...
> HCI Event: Command Complete (0x0e) plen 6
      LE Setup Isochronous Data Path (0x08|0x006e) ncmd 1
        Status: Success (0x00)
        Handle: 257

Signed-off-by: Luiz Augusto von Dentz

Bluetooth: Add support for reading AOSP vendor capabilities

2021-04-06T21:11:23+00:00

When drivers indicate support for AOSP vendor extension, initialize them
and read its capabilities.

Signed-off-by: Marcel Holtmann 
Signed-off-by: Luiz Augusto von Dentz

net: remove redundant 'depends on NET'

2021-01-28T01:04:12+00:00

These Kconfig files are included from net/Kconfig, inside the
if NET ... endif.

Remove 'depends on NET', which we know it is already met.

Signed-off-by: Masahiro Yamada 
Link: https://lore.kernel.org/r/20210125232026.106855-1-masahiroy@kernel.org
Signed-off-by: Jakub Kicinski

Bluetooth: Disable High Speed by default

2020-09-25T18:21:55+00:00

Bluetooth High Speed requires hardware support which is very uncommon
nowadays since HS has not pickup interest by the industry.

Signed-off-by: Luiz Augusto von Dentz 
Signed-off-by: Marcel Holtmann