net/bluetooth/mgmt.c

/*
   BlueZ - Bluetooth protocol stack for Linux
   Copyright (C) 2010  Nokia 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.
*/

/* Bluetooth HCI Management interface */

#include <asm/uaccess.h>
#include <asm/unaligned.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/mgmt.h>

#define MGMT_VERSION	0
#define MGMT_REVISION	1

static int read_version(struct sock *sk)
{
	struct sk_buff *skb;
	struct mgmt_hdr *hdr;
	struct mgmt_ev_cmd_complete *ev;
	struct mgmt_rp_read_version *rp;

	BT_DBG("sock %p", sk);

	skb = alloc_skb(sizeof(*hdr) + sizeof(*ev) + sizeof(*rp), GFP_ATOMIC);
	if (!skb)
		return -ENOMEM;

	hdr = (void *) skb_put(skb, sizeof(*hdr));
	hdr->opcode = cpu_to_le16(MGMT_EV_CMD_COMPLETE);
	hdr->len = cpu_to_le16(sizeof(*ev) + sizeof(*rp));

	ev = (void *) skb_put(skb, sizeof(*ev));
	put_unaligned_le16(MGMT_OP_READ_VERSION, &ev->opcode);

	rp = (void *) skb_put(skb, sizeof(*rp));
	rp->version = MGMT_VERSION;
	put_unaligned_le16(MGMT_REVISION, &rp->revision);

	if (sock_queue_rcv_skb(sk, skb) < 0)
		kfree_skb(skb);

	return 0;
}

static int read_index_list(struct sock *sk)
{
	struct sk_buff *skb;
	struct mgmt_hdr *hdr;
	struct mgmt_ev_cmd_complete *ev;
	struct mgmt_rp_read_index_list *rp;
	struct list_head *p;
	size_t body_len;
	u16 count;
	int i;

	BT_DBG("sock %p", sk);

	read_lock(&hci_dev_list_lock);

	count = 0;
	list_for_each(p, &hci_dev_list) {
		count++;
	}

	body_len = sizeof(*ev) + sizeof(*rp) + (2 * count);
	skb = alloc_skb(sizeof(*hdr) + body_len, GFP_ATOMIC);
	if (!skb)
		return -ENOMEM;

	hdr = (void *) skb_put(skb, sizeof(*hdr));
	hdr->opcode = cpu_to_le16(MGMT_EV_CMD_COMPLETE);
	hdr->len = cpu_to_le16(body_len);

	ev = (void *) skb_put(skb, sizeof(*ev));
	put_unaligned_le16(MGMT_OP_READ_INDEX_LIST, &ev->opcode);

	rp = (void *) skb_put(skb, sizeof(*rp) + (2 * count));
	put_unaligned_le16(count, &rp->num_controllers);

	i = 0;
	list_for_each(p, &hci_dev_list) {
		struct hci_dev *d = list_entry(p, struct hci_dev, list);
		put_unaligned_le16(d->id, &rp->index[i++]);
		BT_DBG("Added hci%u", d->id);
	}

	read_unlock(&hci_dev_list_lock);

	if (sock_queue_rcv_skb(sk, skb) < 0)
		kfree_skb(skb);

	return 0;
}

static int cmd_status(struct sock *sk, u16 cmd, u8 status)
{
	struct sk_buff *skb;
	struct mgmt_hdr *hdr;
	struct mgmt_ev_cmd_status *ev;

	BT_DBG("sock %p", sk);

	skb = alloc_skb(sizeof(*hdr) + sizeof(*ev), GFP_ATOMIC);
	if (!skb)
		return -ENOMEM;

	hdr = (void *) skb_put(skb, sizeof(*hdr));

	hdr->opcode = cpu_to_le16(MGMT_EV_CMD_STATUS);
	hdr->len = cpu_to_le16(sizeof(*ev));

	ev = (void *) skb_put(skb, sizeof(*ev));
	ev->status = status;
	put_unaligned_le16(cmd, &ev->opcode);

	if (sock_queue_rcv_skb(sk, skb) < 0)
		kfree_skb(skb);

	return 0;
}

int mgmt_control(struct sock *sk, struct msghdr *msg, size_t msglen)
{
	unsigned char *buf;
	struct mgmt_hdr *hdr;
	u16 opcode, len;
	int err;

	BT_DBG("got %zu bytes", msglen);

	if (msglen < sizeof(*hdr))
		return -EINVAL;

	buf = kmalloc(msglen, GFP_ATOMIC);
	if (!buf)
		return -ENOMEM;

	if (memcpy_fromiovec(buf, msg->msg_iov, msglen)) {
		err = -EFAULT;
		goto done;
	}

	hdr = (struct mgmt_hdr *) buf;
	opcode = get_unaligned_le16(&hdr->opcode);
	len = get_unaligned_le16(&hdr->len);

	if (len != msglen - sizeof(*hdr)) {
		err = -EINVAL;
		goto done;
	}

	switch (opcode) {
	case MGMT_OP_READ_VERSION:
		err = read_version(sk);
		break;
	case MGMT_OP_READ_INDEX_LIST:
		err = read_index_list(sk);
		break;
	default:
		BT_DBG("Unknown op %u", opcode);
		err = cmd_status(sk, opcode, 0x01);
		break;
	}

	if (err < 0)
		goto done;

	err = msglen;

done:
	kfree(buf);
	return err;
}