[PATCH BlueZ v1 0/2] Introduce option to limit A2DP channels

[PATCH BlueZ v1 0/2] Introduce option to limit A2DP channels

[Victor Pushkarev]

This patch adds feature to limit the number of active A2DP connections.

This may be necessary to prevent audio mixing problem when playing from
multiple sources using A2DP profile.

Victor Pushkarev (2):
  main.conf: Introduce option to limit A2DP channels
  a2dp: Reject connection when the channel limit is exceeded

 profiles/audio/a2dp.c |  8 ++++++++
 src/btd.h             |  6 ++++++
 src/main.c            | 16 ++++++++++++++++
 src/main.conf         |  5 +++++
 4 files changed, 35 insertions(+)

-- 
2.39.3 (Apple Git-145)

[PATCH BlueZ v1 1/2] main.conf: Introduce option to limit A2DP channels

[Victor Pushkarev]

This introduces Channels which can be used to
limit the number of A2DP channels.

For new option this also adds a new group A2DP to config.

Signed-off-by: Victor Pushkarev <VAnPushkarev@salutedevices.com>
---
 src/btd.h     |  6 ++++++
 src/main.c    | 16 ++++++++++++++++
 src/main.conf |  5 +++++
 3 files changed, 27 insertions(+)

diff --git a/src/btd.h b/src/btd.h
index b7e7ebd61..3372bd7f5 100644
--- a/src/btd.h
+++ b/src/btd.h
@@ -104,6 +104,10 @@ struct btd_avdtp_opts {
 	uint8_t  stream_mode;
 };
 
+struct btd_a2dp_opts {
+	uint8_t		channels;
+};
+
 struct btd_advmon_opts {
 	uint8_t		rssi_sampling_period;
 };
@@ -148,6 +152,8 @@ struct btd_opts {
 
 	enum jw_repairing_t jw_repairing;
 
+	struct btd_a2dp_opts	a2dp;
+
 	struct btd_advmon_opts	advmon;
 
 	struct btd_csis csis;
diff --git a/src/main.c b/src/main.c
index b1339c230..7e74b9728 100644
--- a/src/main.c
+++ b/src/main.c
@@ -162,6 +162,11 @@ static const char *avdtp_options[] = {
 	NULL
 };
 
+static const char *a2dp_options[] = {
+	"Channels",
+	NULL
+};
+
 static const char *advmon_options[] = {
 	"RSSISamplingPeriod",
 	NULL
@@ -178,6 +183,7 @@ static const struct group_table {
 	{ "GATT",	gatt_options },
 	{ "CSIS",	csip_options },
 	{ "AVDTP",	avdtp_options },
+	{ "A2DP",	a2dp_options },
 	{ "AdvMon",	advmon_options },
 	{ }
 };
@@ -1130,6 +1136,13 @@ static void parse_avdtp(GKeyFile *config)
 	parse_avdtp_stream_mode(config);
 }
 
+static void parse_a2dp(GKeyFile *config)
+{
+	parse_config_u8(config, "A2DP", "Channels",
+				&btd_opts.a2dp.channels,
+				0, UINT8_MAX);
+}
+
 static void parse_advmon(GKeyFile *config)
 {
 	parse_config_u8(config, "AdvMon", "RSSISamplingPeriod",
@@ -1153,6 +1166,7 @@ static void parse_config(GKeyFile *config)
 	parse_gatt(config);
 	parse_csis(config);
 	parse_avdtp(config);
+	parse_a2dp(config);
 	parse_advmon(config);
 }
 
@@ -1194,6 +1208,8 @@ static void init_defaults(void)
 	btd_opts.avdtp.session_mode = BT_IO_MODE_BASIC;
 	btd_opts.avdtp.stream_mode = BT_IO_MODE_BASIC;
 
+	btd_opts.a2dp.channels = 0;
+
 	btd_opts.advmon.rssi_sampling_period = 0xFF;
 	btd_opts.csis.encrypt = true;
 }
diff --git a/src/main.conf b/src/main.conf
index 085c81a46..caeb82504 100644
--- a/src/main.conf
+++ b/src/main.conf
@@ -296,6 +296,11 @@
 # streaming: Use L2CAP Streaming Mode
 #StreamMode = basic
 
+[A2DP]
+# Maximum number of A2DP channels
+# Defaults to 0 (unlimited)
+#Channels = 0
+
 [Policy]
 #
 # The ReconnectUUIDs defines the set of remote services that should try
-- 
2.39.3 (Apple Git-145)

[PATCH BlueZ v1 2/2] a2dp: Reject connection when the channel limit is exceeded

[Victor Pushkarev]

Reject incoming connection when the configured limit
for A2DP channels is exceeded.

Signed-off-by: Victor Pushkarev <VAnPushkarev@salutedevices.com>
---
 profiles/audio/a2dp.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/profiles/audio/a2dp.c b/profiles/audio/a2dp.c
index b43161a13..117b27db3 100644
--- a/profiles/audio/a2dp.c
+++ b/profiles/audio/a2dp.c
@@ -2549,6 +2549,14 @@ static void confirm_cb(GIOChannel *io, gpointer data)
 	if (!chan)
 		goto drop;
 
+	if (btd_opts.a2dp.channels &&
+				queue_length(server->channels) > btd_opts.a2dp.channels) {
+		device_request_disconnect(device, NULL);
+		DBG("Reject current connection, A2DP channel limit exceeded: %d",
+						btd_opts.a2dp.channels);
+		goto drop;
+	}
+
 	chan->auth_id = btd_request_authorization(&src, &dst,
 							ADVANCED_AUDIO_UUID,
 							auth_cb, chan);
-- 
2.39.3 (Apple Git-145)

Re: [PATCH BlueZ v1 2/2] a2dp: Reject connection when the channel limit is exceeded

[Luiz Augusto von Dentz]

Hi,

On Mon, Jan 29, 2024 at 3:42 PM Victor Pushkarev
<VAnPushkarev@salutedevices.com> wrote:
>
> Reject incoming connection when the configured limit
> for A2DP channels is exceeded.
>
> Signed-off-by: Victor Pushkarev <VAnPushkarev@salutedevices.com>
> ---
>  profiles/audio/a2dp.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/profiles/audio/a2dp.c b/profiles/audio/a2dp.c
> index b43161a13..117b27db3 100644
> --- a/profiles/audio/a2dp.c
> +++ b/profiles/audio/a2dp.c
> @@ -2549,6 +2549,14 @@ static void confirm_cb(GIOChannel *io, gpointer data)
>         if (!chan)
>                 goto drop;
>
> +       if (btd_opts.a2dp.channels &&
> +                               queue_length(server->channels) > btd_opts.a2dp.channels) {
> +               device_request_disconnect(device, NULL);
> +               DBG("Reject current connection, A2DP channel limit exceeded: %d",
> +                                               btd_opts.a2dp.channels);
> +               goto drop;
> +       }

NAK, this is the wrong layer to do this, it is up to the MediaEndpoint
implementation to tell how many streams it can handle.

>         chan->auth_id = btd_request_authorization(&src, &dst,
>                                                         ADVANCED_AUDIO_UUID,
>                                                         auth_cb, chan);
> --
> 2.39.3 (Apple Git-145)
>
>


-- 
Luiz Augusto von Dentz

RE: Introduce option to limit A2DP channels

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 2901 bytes --]

This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=821056

---Test result---

Test Summary:
CheckPatch                    FAIL      1.20 seconds
GitLint                       PASS      0.64 seconds
BuildEll                      PASS      24.30 seconds
BluezMake                     PASS      744.06 seconds
MakeCheck                     PASS      11.58 seconds
MakeDistcheck                 PASS      164.00 seconds
CheckValgrind                 PASS      227.32 seconds
CheckSmatch                   PASS      333.77 seconds
bluezmakeextell               PASS      109.57 seconds
IncrementalBuild              PASS      1374.21 seconds
ScanBuild                     PASS      955.44 seconds

Details
##############################
Test: CheckPatch - FAIL
Desc: Run checkpatch.pl script
Output:
[BlueZ,v1,1/2] main.conf: Introduce option to limit A2DP channels
WARNING:STATIC_CONST_CHAR_ARRAY: static const char * array should probably be static const char * const
#145: FILE: src/main.c:165:
+static const char *a2dp_options[] = {

/github/workspace/src/src/13536361.patch total: 0 errors, 1 warnings, 75 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

/github/workspace/src/src/13536361.patch has style problems, please review.

NOTE: Ignored message types: COMMIT_MESSAGE COMPLEX_MACRO CONST_STRUCT FILE_PATH_CHANGES MISSING_SIGN_OFF PREFER_PACKED SPDX_LICENSE_TAG SPLIT_STRING SSCANF_TO_KSTRTO

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.


[BlueZ,v1,2/2] a2dp: Reject connection when the channel limit is exceeded
WARNING:LONG_LINE: line length of 90 exceeds 80 columns
#118: FILE: profiles/audio/a2dp.c:2553:
+				queue_length(server->channels) > btd_opts.a2dp.channels) {

WARNING:LONG_LINE_STRING: line length of 81 exceeds 80 columns
#120: FILE: profiles/audio/a2dp.c:2555:
+		DBG("Reject current connection, A2DP channel limit exceeded: %d",

/github/workspace/src/src/13536360.patch total: 0 errors, 2 warnings, 14 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

/github/workspace/src/src/13536360.patch has style problems, please review.

NOTE: Ignored message types: COMMIT_MESSAGE COMPLEX_MACRO CONST_STRUCT FILE_PATH_CHANGES MISSING_SIGN_OFF PREFER_PACKED SPDX_LICENSE_TAG SPLIT_STRING SSCANF_TO_KSTRTO

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.




---
Regards,
Linux Bluetooth

RE: Introduce option to limit A2DP channels

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 3349 bytes --]

This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=907547

---Test result---

Test Summary:
CheckPatch                    FAIL      1.02 seconds
GitLint                       PASS      0.63 seconds
BuildEll                      PASS      25.51 seconds
BluezMake                     PASS      1739.17 seconds
MakeCheck                     PASS      12.98 seconds
MakeDistcheck                 PASS      178.52 seconds
CheckValgrind                 PASS      252.44 seconds
CheckSmatch                   PASS      356.62 seconds
bluezmakeextell               PASS      122.75 seconds
IncrementalBuild              PASS      3101.50 seconds
ScanBuild                     WARNING   1008.31 seconds

Details
##############################
Test: CheckPatch - FAIL
Desc: Run checkpatch.pl script
Output:
[BlueZ,1/2] main.conf: Introduce option to limit A2DP channels
WARNING:STATIC_CONST_CHAR_ARRAY: static const char * array should probably be static const char * const
#140: FILE: src/main.c:173:
+static const char *a2dp_options[] = {

/github/workspace/src/src/13867230.patch total: 0 errors, 1 warnings, 74 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

/github/workspace/src/src/13867230.patch has style problems, please review.

NOTE: Ignored message types: COMMIT_MESSAGE COMPLEX_MACRO CONST_STRUCT FILE_PATH_CHANGES MISSING_SIGN_OFF PREFER_PACKED SPDX_LICENSE_TAG SPLIT_STRING SSCANF_TO_KSTRTO

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.


[BlueZ,2/2] a2dp: Reject incoming connection when channel limit is exceeded
WARNING:BLOCK_COMMENT_STYLE: Block comments should align the * on each line
#116: FILE: profiles/audio/a2dp.c:721:
+			/* Reject connection from SEP
+			* and clear configuration.

WARNING:LONG_LINE: line length of 95 exceeds 80 columns
#118: FILE: profiles/audio/a2dp.c:723:
+			DBG("Reject connection from %s", device_get_path(setup->chan->device));

WARNING:LONG_LINE: line length of 95 exceeds 80 columns
#119: FILE: profiles/audio/a2dp.c:724:
+			a2dp_sep->endpoint->clear_configuration(a2dp_sep, a2dp_sep->user_data);

/github/workspace/src/src/13867231.patch total: 0 errors, 3 warnings, 50 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

/github/workspace/src/src/13867231.patch has style problems, please review.

NOTE: Ignored message types: COMMIT_MESSAGE COMPLEX_MACRO CONST_STRUCT FILE_PATH_CHANGES MISSING_SIGN_OFF PREFER_PACKED SPDX_LICENSE_TAG SPLIT_STRING SSCANF_TO_KSTRTO

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.


##############################
Test: ScanBuild - WARNING
Desc: Run Scan Build
Output:
profiles/audio/media.c:1059:7: warning: Use of memory after it is freed
                if (req->cb != pac_select_cb) {
                    ^~~~~~~
1 warning generated.



---
Regards,
Linux Bluetooth