[PATCH BlueZ v5 2/3] main.conf: Add Channel Sounding config parsing support

[Naga Bhavani Akella <naga.akella@oss.qualcomm.com>]

Add support for parsing Channel Sounding (CS) configuration options
from the configuration file.

Add CAP_NET_RAW to CapabilityBoundingSet in bluetooth.service.
bluetoothd requires CAP_NET_RAW to receive and process HCI LE events
when running under a constrained systemd capability bounding set
---
 src/bluetooth.service.in |   2 +-
 src/btd.h                |   7 +++
 src/main.c               | 129 +++++++++++++++++++++++++++++++++++++++
 src/main.conf            |  24 ++++++++
 4 files changed, 161 insertions(+), 1 deletion(-)

diff --git a/src/bluetooth.service.in b/src/bluetooth.service.in
index 8ebe89bec..8dcbde236 100644
--- a/src/bluetooth.service.in
+++ b/src/bluetooth.service.in
@@ -10,7 +10,7 @@ ExecStart=@PKGLIBEXECDIR@/bluetoothd
 NotifyAccess=main
 #WatchdogSec=10
 #Restart=on-failure
-CapabilityBoundingSet=CAP_NET_ADMIN CAP_NET_BIND_SERVICE
+CapabilityBoundingSet=CAP_NET_RAW CAP_NET_ADMIN CAP_NET_BIND_SERVICE
 LimitNPROC=1
 
 # Filesystem lockdown
diff --git a/src/btd.h b/src/btd.h
index c84a600d1..db2e81239 100644
--- a/src/btd.h
+++ b/src/btd.h
@@ -94,11 +94,18 @@ struct btd_le_defaults {
 	uint8_t		enable_advmon_interleave_scan;
 };
 
+struct btd_le_bcs {
+	uint8_t role;
+	uint8_t cs_sync_ant_sel;
+	int8_t max_tx_power;
+};
+
 struct btd_defaults {
 	uint16_t	num_entries;
 
 	struct btd_br_defaults br;
 	struct btd_le_defaults le;
+	struct btd_le_bcs bcs;
 };
 
 struct btd_csis {
diff --git a/src/main.c b/src/main.c
index 818f7c06e..d3a2528e3 100644
--- a/src/main.c
+++ b/src/main.c
@@ -156,6 +156,13 @@ static const char *gatt_options[] = {
 	NULL
 };
 
+static const char *bcs_options[] = {
+	"Role",
+	"CsSyncAntennaSel",
+	"MaxTxPower",
+	NULL
+};
+
 static const char *csip_options[] = {
 	"SIRK",
 	"Encryption",
@@ -193,6 +200,7 @@ static const struct group_table {
 	{ "CSIS",	csip_options },
 	{ "AVDTP",	avdtp_options },
 	{ "AVRCP",	avrcp_options },
+	{ "ChannelSounding",	bcs_options },
 	{ "AdvMon",	advmon_options },
 	{ }
 };
@@ -492,6 +500,46 @@ static bool parse_config_int(GKeyFile *config, const char *group,
 	return true;
 }
 
+static bool parse_config_signed_int(GKeyFile *config, const char *group,
+					const char *key, int8_t *val,
+					size_t min, size_t max)
+{
+	char *str = NULL;
+	char *endptr = NULL;
+	long tmp;
+	bool result = false;
+
+	str = g_key_file_get_string(config, group, key, NULL);
+	if (!str)
+		return false;
+
+	tmp = strtol(str, &endptr, 0);
+	if (!endptr || *endptr != '\0') {
+		warn("%s.%s = %s is not integer", group, key, str);
+		goto cleanup;
+	}
+
+	if (tmp < (long)min) {
+		warn("%s.%s = %ld is out of range (< %zu)", group, key, tmp,
+			min);
+		goto cleanup;
+	}
+
+	if (tmp > (long)max) {
+		warn("%s.%s = %ld is out of range (> %zu)", group, key, tmp,
+									max);
+		goto cleanup;
+	}
+
+	if (val)
+		*val = (int8_t)tmp;
+	result = true;
+
+cleanup:
+	g_free(str);
+	return result;
+}
+
 struct config_param {
 	const char * const val_name;
 	void * const val;
@@ -1184,6 +1232,82 @@ static void parse_csis(GKeyFile *config)
 					0, UINT8_MAX);
 }
 
+static bool parse_cs_role(GKeyFile *config, const char *group,
+					const char *key, uint8_t *val)
+{
+	GError *err = NULL;
+	char *str = NULL;
+	int numeric_val;
+
+	/* Try to read as string first */
+	str = g_key_file_get_string(config, group, key, &err);
+	if (err) {
+		if (err->code != G_KEY_FILE_ERROR_KEY_NOT_FOUND)
+			DBG("%s", err->message);
+		g_error_free(err);
+		return false;
+	}
+
+	DBG("%s.%s = %s", group, key, str);
+
+	/* Check if it's a string value */
+	if (!strcmp(str, "Initiator") || !strcmp(str, "initiator")) {
+		if (val)
+			*val = 1;
+		g_free(str);
+		return true;
+	} else if (!strcmp(str, "Reflector") || !strcmp(str, "reflector")) {
+		if (val)
+			*val = 2;
+		g_free(str);
+		return true;
+	} else if (!strcmp(str, "Both") || !strcmp(str, "both")) {
+		if (val)
+			*val = 3;
+		g_free(str);
+		return true;
+	}
+
+	/* Try to parse as numeric value */
+	char *endptr = NULL;
+
+	numeric_val = strtol(str, &endptr, 0);
+
+	if (!endptr || *endptr != '\0') {
+		error("%s.%s = %s is not a valid value. "
+			"Expected: 1/Initiator, 2/Reflector, or 3/Both",
+			group, key, str);
+		g_free(str);
+		return false;
+	}
+
+	if (numeric_val < 1 || numeric_val > 3) {
+		warn("%s.%s = %d is out of range. "
+			"Valid values: 1 (Initiator), 2 (Reflector), 3 (Both)",
+			group, key, numeric_val);
+		g_free(str);
+		return false;
+	}
+
+	if (val)
+		*val = numeric_val;
+
+	g_free(str);
+	return true;
+}
+
+static void parse_le_cs_config(GKeyFile *config)
+{
+	parse_cs_role(config, "ChannelSounding", "Role",
+			&btd_opts.defaults.bcs.role);
+	parse_config_u8(config, "ChannelSounding", "CsSyncAntennaSel",
+			&btd_opts.defaults.bcs.cs_sync_ant_sel,
+			0x01, 0xFF);
+	parse_config_signed_int(config, "ChannelSounding",
+			"MaxTxPower", &btd_opts.defaults.bcs.max_tx_power,
+			INT8_MIN, INT8_MAX);
+}
+
 static void parse_avdtp_session_mode(GKeyFile *config)
 {
 	char *str = NULL;
@@ -1262,6 +1386,7 @@ static void parse_config(GKeyFile *config)
 	parse_csis(config);
 	parse_avdtp(config);
 	parse_avrcp(config);
+	parse_le_cs_config(config);
 	parse_advmon(config);
 }
 
@@ -1313,6 +1438,10 @@ static void init_defaults(void)
 
 	btd_opts.advmon.rssi_sampling_period = 0xFF;
 	btd_opts.csis.encrypt = true;
+
+	btd_opts.defaults.bcs.role = 0x03;
+	btd_opts.defaults.bcs.cs_sync_ant_sel = 0xFF;
+	btd_opts.defaults.bcs.max_tx_power = 0x14;
 }
 
 static void log_handler(const gchar *log_domain, GLogLevelFlags log_level,
diff --git a/src/main.conf b/src/main.conf
index d31dd1b8f..fc0138bbf 100644
--- a/src/main.conf
+++ b/src/main.conf
@@ -299,6 +299,30 @@
 # Default = auto
 # Security = auto
 
+[ChannelSounding]
+# Current role of the device
+# Possible values:
+#   1 or "Initiator" - CS Initiator role,
+#   Generally, CS Initiator acts as Client (Gatt role) and Central (Gap role)
+#   2 or "Reflector" - CS Reflector role,
+#   Generally, CS Reflector acts as Server (Gatt role) and Peripheral (Gap role)
+#   3 or "Both"      - Both Initiator and Reflector roles
+# Default: 3 (Both)
+#Role = 3
+
+# Antenna Identifier to be used
+# Possible values:
+# 0x01-0x04 (antenna identifier to be used),
+# 0xFE - Antennas to be used in repetetive order,
+# 0xFF - Host doen't have recommendation
+# Default: 0xFF (Host doesn't have recommendation)
+#CsSyncAntennaSel = 0xFF
+
+# Maximum Transmit power
+# Possible values: 0x7F-0x14 (-127dBm to 20dBm)
+# Default: 0x14 (Max Power possible)
+#MaxTxPower = 0x14
+
 [CSIS]
 # SIRK - Set Identification Resolution Key which is common for all the
 # sets. They SIRK key is used to identify its sets. This can be any
--