Bluetooth: Add BTPROTO_ISO socket type

This introduces a new socket type BTPROTO_ISO which can be enabled with
use of ISO Socket experiemental UUID, it can used to initiate/accept
connections and transfer packets between userspace and kernel similarly
to how BTPROTO_SCO works:

Central -> uses connect with address set to destination bdaddr:
> tools/isotest -s 00:AA:01:00:00:00

Peripheral -> uses listen:
> tools/isotest -d

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

include/net/bluetooth/bluetooth.h

@@ -589,6 +589,27 @@ static inline void sco_exit(void)
 }
 #endif
 
+#if IS_ENABLED(CONFIG_BT_LE)
+int iso_init(void);
+int iso_exit(void);
+bool iso_enabled(void);
+#else
+static inline int iso_init(void)
+{
+	return 0;
+}
+
+static inline int iso_exit(void)
+{
+	return 0;
+}
+
+static inline bool iso_enabled(void)
+{
+	return false;
+}
+#endif
+
 int mgmt_init(void);
 void mgmt_exit(void);
 

include/net/bluetooth/hci_core.h

@@ -834,6 +834,21 @@ static inline void sco_recv_scodata(struct hci_conn *hcon, struct sk_buff *skb)
 }
 #endif
 
+#if IS_ENABLED(CONFIG_BT_LE)
+int iso_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr, __u8 *flags);
+void iso_recv(struct hci_conn *hcon, struct sk_buff *skb, u16 flags);
+#else
+static inline int iso_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr,
+				  __u8 *flags)
+{
+	return 0;
+}
+static inline void iso_recv(struct hci_conn *hcon, struct sk_buff *skb,
+			    u16 flags)
+{
+}
+#endif
+
 /* ----- Inquiry cache ----- */
 #define INQUIRY_CACHE_AGE_MAX   (HZ*30)   /* 30 seconds */
 #define INQUIRY_ENTRY_AGE_MAX   (HZ*60)   /* 60 seconds */
@@ -1632,8 +1647,7 @@ static inline int hci_proto_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr,
 		return sco_connect_ind(hdev, bdaddr, flags);
 
 	case ISO_LINK:
-		/* TODO: Handle connection indication */
-		return -EINVAL;
+		return iso_connect_ind(hdev, bdaddr, flags);
 
 	default:
 		BT_ERR("unknown link type %d", type);

include/net/bluetooth/iso.h

@@ -0,0 +1,36 @@
+/*
+   BlueZ - Bluetooth protocol stack for Linux
+   Copyright (C) 2020 Intel Corporation
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License version 2 as
+   published by the Free Software Foundation;
+
+   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
+   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
+   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
+   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
+   SOFTWARE IS DISCLAIMED.
+*/
+
+#ifndef __ISO_H
+#define __ISO_H
+
+/* ISO defaults */
+#define ISO_DEFAULT_MTU		251
+
+/* ISO socket address */
+struct sockaddr_iso {
+	sa_family_t	iso_family;
+	bdaddr_t	iso_bdaddr;
+	__u8		iso_bdaddr_type;
+};
+
+#endif /* __ISO_H */

net/bluetooth/Makefile

@@ -18,6 +18,7 @@ bluetooth-y := af_bluetooth.o hci_core.o hci_conn.o hci_event.o mgmt.o \
 	eir.o hci_sync.o
 
 bluetooth-$(CONFIG_BT_BREDR) += sco.o
+bluetooth-$(CONFIG_BT_LE) += iso.o
 bluetooth-$(CONFIG_BT_HS) += a2mp.o amp.o
 bluetooth-$(CONFIG_BT_LEDS) += leds.o
 bluetooth-$(CONFIG_BT_MSFTEXT) += msft.o

net/bluetooth/af_bluetooth.c

@@ -780,6 +780,8 @@ static void __exit bt_exit(void)
 {
 	mgmt_exit();
 
+	iso_exit();
+
 	sco_exit();
 
 	l2cap_exit();

net/bluetooth/hci_core.c

@@ -3822,8 +3822,11 @@ static void hci_isodata_packet(struct hci_dev *hdev, struct sk_buff *skb)
 	conn = hci_conn_hash_lookup_handle(hdev, handle);
 	hci_dev_unlock(hdev);
 
-	/* TODO: Send to upper protocol */
-	if (!conn) {
+	if (conn) {
+		/* Send to upper protocol */
+		iso_recv(conn, skb, flags);
+		return;
+	} else {
 		bt_dev_err(hdev, "ISO packet for unknown connection handle %d",
 			   handle);
 	}

net/bluetooth/hci_event.c

@@ -3827,8 +3827,8 @@ static u8 hci_cc_le_set_cig_params(struct hci_dev *hdev, void *data,
 
 		conn->handle = __le16_to_cpu(rp->handle[i++]);
 
-		BT_DBG("%p handle 0x%4.4x link %p state %u", conn, conn->handle,
-		       conn->link, conn->link->state);
+		bt_dev_dbg(hdev, "%p handle 0x%4.4x link %p state %u", conn,
+			   conn->handle, conn->link, conn->link->state);
 
 		/* Create CIS if LE is already connected */
 		if (conn->link->state == BT_CONNECTED)