3 files changed, 104 insertions, 0 deletions

diff --git a/include/net/bluetooth/hci_mon.h b/include/net/bluetooth/hci_mon.h
index c91bb23eb29e..587d0131b349 100644
--- a/include/net/bluetooth/hci_mon.h
+++ b/include/net/bluetooth/hci_mon.h
@@ -44,6 +44,7 @@ struct hci_mon_hdr {
 #define HCI_MON_INDEX_INFO	10
 #define HCI_MON_VENDOR_DIAG	11
 #define HCI_MON_SYSTEM_NOTE	12
+#define HCI_MON_USER_LOGGING	13
 
 struct hci_mon_new_index {
 	__u8		type;
diff --git a/include/net/bluetooth/hci_sock.h b/include/net/bluetooth/hci_sock.h
index 9a46d665c1b5..8e9138acdae1 100644
--- a/include/net/bluetooth/hci_sock.h
+++ b/include/net/bluetooth/hci_sock.h
@@ -45,6 +45,7 @@ struct sockaddr_hci {
 #define HCI_CHANNEL_USER	1
 #define HCI_CHANNEL_MONITOR	2
 #define HCI_CHANNEL_CONTROL	3
+#define HCI_CHANNEL_LOGGING	4
 
 struct hci_filter {
 	unsigned long type_mask;
diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c
index 710265c35d16..41f579ba447b 100644
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -906,6 +906,18 @@ static int hci_sock_bind(struct socket *sock, struct sockaddr *addr,
 		atomic_inc(&monitor_promisc);
 		break;
 
+	case HCI_CHANNEL_LOGGING:
+		if (haddr.hci_dev != HCI_DEV_NONE) {
+			err = -EINVAL;
+			goto done;
+		}
+
+		if (!capable(CAP_NET_ADMIN)) {
+			err = -EPERM;
+			goto done;
+		}
+		break;
+
 	default:
 		if (!hci_mgmt_chan_find(haddr.hci_channel)) {
 			err = -EINVAL;
@@ -1033,6 +1045,9 @@ static int hci_sock_recvmsg(struct socket *sock, struct msghdr *msg,
 	if (flags & MSG_OOB)
 		return -EOPNOTSUPP;
 
+	if (hci_pi(sk)->channel == HCI_CHANNEL_LOGGING)
+		return -EOPNOTSUPP;
+
 	if (sk->sk_state == BT_CLOSED)
 		return 0;
 
@@ -1179,6 +1194,90 @@ done:
 	return err;
 }
 
+static int hci_logging_frame(struct sock *sk, struct msghdr *msg, int len)
+{
+	struct hci_mon_hdr *hdr;
+	struct sk_buff *skb;
+	struct hci_dev *hdev;
+	u16 index;
+	int err;
+
+	/* The logging frame consists at minimum of the standard header,
+	 * the priority byte, the ident length byte and at least one string
+	 * terminator NUL byte. Anything shorter are invalid packets.
+	 */
+	if (len < sizeof(*hdr) + 3)
+		return -EINVAL;
+
+	skb = bt_skb_send_alloc(sk, len, msg->msg_flags & MSG_DONTWAIT, &err);
+	if (!skb)
+		return err;
+
+	if (memcpy_from_msg(skb_put(skb, len), msg, len)) {
+		err = -EFAULT;
+		goto drop;
+	}
+
+	hdr = (void *)skb->data;
+
+	if (__le16_to_cpu(hdr->len) != len - sizeof(*hdr)) {
+		err = -EINVAL;
+		goto drop;
+	}
+
+	if (__le16_to_cpu(hdr->opcode) == 0x0000) {
+		__u8 priority = skb->data[sizeof(*hdr)];
+		__u8 ident_len = skb->data[sizeof(*hdr) + 1];
+
+		/* Only the priorities 0-7 are valid and with that any other
+		 * value results in an invalid packet.
+		 *
+		 * The priority byte is followed by an ident length byte and
+		 * the NUL terminated ident string. Check that the ident
+		 * length is not overflowing the packet and also that the
+		 * ident string itself is NUL terminated. In case the ident
+		 * length is zero, the length value actually doubles as NUL
+		 * terminator identifier.
+		 *
+		 * The message follows the ident string (if present) and
+		 * must be NUL terminated. Otherwise it is not a valid packet.
+		 */
+		if (priority > 7 || skb->data[len - 1] != 0x00 ||
+		    ident_len > len - sizeof(*hdr) - 3 ||
+		    skb->data[sizeof(*hdr) + ident_len + 1] != 0x00) {
+			err = -EINVAL;
+			goto drop;
+		}
+	} else {
+		err = -EINVAL;
+		goto drop;
+	}
+
+	index = __le16_to_cpu(hdr->index);
+
+	if (index != MGMT_INDEX_NONE) {
+		hdev = hci_dev_get(index);
+		if (!hdev) {
+			err = -ENODEV;
+			goto drop;
+		}
+	} else {
+		hdev = NULL;
+	}
+
+	hdr->opcode = cpu_to_le16(HCI_MON_USER_LOGGING);
+
+	hci_send_to_channel(HCI_CHANNEL_MONITOR, skb, HCI_SOCK_TRUSTED, NULL);
+	err = len;
+
+	if (hdev)
+		hci_dev_put(hdev);
+
+drop:
+	kfree_skb(skb);
+	return err;
+}
+
 static int hci_sock_sendmsg(struct socket *sock, struct msghdr *msg,
 			    size_t len)
 {
@@ -1208,6 +1307,9 @@ static int hci_sock_sendmsg(struct socket *sock, struct msghdr *msg,
 	case HCI_CHANNEL_MONITOR:
 		err = -EOPNOTSUPP;
 		goto done;
+	case HCI_CHANNEL_LOGGING:
+		err = hci_logging_frame(sk, msg, len);
+		goto done;
 	default:
 		mutex_lock(&mgmt_chan_list_lock);
 		chan = __hci_mgmt_chan_find(hci_pi(sk)->channel);