// SPDX-License-Identifier: GPL-2.0-only/* * Copyright (C) 2020 Google Corporation */ #include <net/bluetooth/bluetooth.h>#include <net/bluetooth/hci_core.h> #include "msft.h" #define MSFT_OP_READ_SUPPORTED_FEATURES		0x00struct msft_cp_read_supported_features {	__u8   sub_opcode;} __packed;struct msft_rp_read_supported_features {	__u8   status;	__u8   sub_opcode;	__le64 features;	__u8   evt_prefix_len;	__u8   evt_prefix[0];} __packed; struct msft_data {	__u64 features;	__u8  evt_prefix_len;	__u8  *evt_prefix;}; static bool read_supported_features(struct hci_dev *hdev,				    struct msft_data *msft){	struct msft_cp_read_supported_features cp;	struct msft_rp_read_supported_features *rp;	struct sk_buff *skb; 	cp.sub_opcode = MSFT_OP_READ_SUPPORTED_FEATURES; 	skb = __hci_cmd_sync(hdev, hdev->msft_opcode, sizeof(cp), &cp,			     HCI_CMD_TIMEOUT);	if (IS_ERR(skb)) {		bt_dev_err(hdev, "Failed to read MSFT supported features (%ld)",			   PTR_ERR(skb));		return false;	} 	if (skb->len < sizeof(*rp)) {		bt_dev_err(hdev, "MSFT supported features length mismatch");		goto failed;	} 	rp = (struct msft_rp_read_supported_features *)skb->data; 	if (rp->sub_opcode != MSFT_OP_READ_SUPPORTED_FEATURES)		goto failed; 	if (rp->evt_prefix_len > 0) {		msft->evt_prefix = kmemdup(rp->evt_prefix, rp->evt_prefix_len,					   GFP_KERNEL);		if (!msft->evt_prefix)			goto failed;	} 	msft->evt_prefix_len = rp->evt_prefix_len;	msft->features = __le64_to_cpu(rp->features); 	kfree_skb(skb);	return true; failed:	kfree_skb(skb);	return false;} void msft_do_open(struct hci_dev *hdev){	struct msft_data *msft; 	if (hdev->msft_opcode == HCI_OP_NOP)		return; 	bt_dev_dbg(hdev, "Initialize MSFT extension"); 	msft = kzalloc(sizeof(*msft), GFP_KERNEL);	if (!msft)		return; 	if (!read_supported_features(hdev, msft)) {		kfree(msft);		return;	} 	hdev->msft_data = msft;} void msft_do_close(struct hci_dev *hdev){	struct msft_data *msft = hdev->msft_data; 	if (!msft)		return; 	bt_dev_dbg(hdev, "Cleanup of MSFT extension"); 	hdev->msft_data = NULL; 	kfree(msft->evt_prefix);	kfree(msft);} void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb){	struct msft_data *msft = hdev->msft_data;	u8 event; 	if (!msft)		return; 	/* When the extension has defined an event prefix, check that it	 * matches, and otherwise just return.	 */	if (msft->evt_prefix_len > 0) {		if (skb->len < msft->evt_prefix_len)			return; 		if (memcmp(skb->data, msft->evt_prefix, msft->evt_prefix_len))			return; 		skb_pull(skb, msft->evt_prefix_len);	} 	/* Every event starts at least with an event code and the rest of	 * the data is variable and depends on the event code.	 */	if (skb->len < 1)		return; 	event = *skb->data;	skb_pull(skb, 1); 	bt_dev_dbg(hdev, "MSFT vendor event %u", event);} __u64 msft_get_features(struct hci_dev *hdev){	struct msft_data *msft = hdev->msft_data; 	return  msft ? msft->features : 0;}