path: root/net/nfc/netlink.c

/*
 * Copyright (C) 2011 Instituto Nokia de Tecnologia
 *
 * Authors:
 *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
 *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the
 * Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__

#include <net/genetlink.h>
#include <linux/nfc.h>
#include <linux/slab.h>

#include "nfc.h"

static struct genl_multicast_group nfc_genl_event_mcgrp = {
	.name = NFC_GENL_MCAST_EVENT_NAME,
};

static struct genl_family nfc_genl_family = {
	.id = GENL_ID_GENERATE,
	.hdrsize = 0,
	.name = NFC_GENL_NAME,
	.version = NFC_GENL_VERSION,
	.maxattr = NFC_ATTR_MAX,
};

static const struct nla_policy nfc_genl_policy[NFC_ATTR_MAX + 1] = {
	[NFC_ATTR_DEVICE_INDEX] = { .type = NLA_U32 },
	[NFC_ATTR_DEVICE_NAME] = { .type = NLA_STRING,
				.len = NFC_DEVICE_NAME_MAXSIZE },
	[NFC_ATTR_PROTOCOLS] = { .type = NLA_U32 },
	[NFC_ATTR_COMM_MODE] = { .type = NLA_U8 },
	[NFC_ATTR_RF_MODE] = { .type = NLA_U8 },
	[NFC_ATTR_DEVICE_POWERED] = { .type = NLA_U8 },
	[NFC_ATTR_IM_PROTOCOLS] = { .type = NLA_U32 },
	[NFC_ATTR_TM_PROTOCOLS] = { .type = NLA_U32 },
};

static int nfc_genl_send_target(struct sk_buff *msg, struct nfc_target *target,
				struct netlink_callback *cb, int flags)
{
	void *hdr;

	hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
			  &nfc_genl_family, flags, NFC_CMD_GET_TARGET);
	if (!hdr)
		return -EMSGSIZE;

	genl_dump_check_consistent(cb, hdr, &nfc_genl_family);

	if (nla_put_u32(msg, NFC_ATTR_TARGET_INDEX, target->idx) ||
	    nla_put_u32(msg, NFC_ATTR_PROTOCOLS, target->supported_protocols) ||
	    nla_put_u16(msg, NFC_ATTR_TARGET_SENS_RES, target->sens_res) ||
	    nla_put_u8(msg, NFC_ATTR_TARGET_SEL_RES, target->sel_res))
		goto nla_put_failure;
	if (target->nfcid1_len > 0 &&
	    nla_put(msg, NFC_ATTR_TARGET_NFCID1, target->nfcid1_len,
		    target->nfcid1))
		goto nla_put_failure;
	if (target->sensb_res_len > 0 &&
	    nla_put(msg, NFC_ATTR_TARGET_SENSB_RES, target->sensb_res_len,
		    target->sensb_res))
		goto nla_put_failure;
	if (target->sensf_res_len > 0 &&
	    nla_put(msg, NFC_ATTR_TARGET_SENSF_RES, target->sensf_res_len,
		    target->sensf_res))
		goto nla_put_failure;

	return genlmsg_end(msg, hdr);

nla_put_failure:
	genlmsg_cancel(msg, hdr);
	return -EMSGSIZE;
}

static struct nfc_dev *__get_device_from_cb(struct netlink_callback *cb)
{
	struct nfc_dev *dev;
	int rc;
	u32 idx;

	rc = nlmsg_parse(cb->nlh, GENL_HDRLEN + nfc_genl_family.hdrsize,
			 nfc_genl_family.attrbuf,
			 nfc_genl_family.maxattr,
			 nfc_genl_policy);
	if (rc < 0)
		return ERR_PTR(rc);

	if (!nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX])
		return ERR_PTR(-EINVAL);

	idx = nla_get_u32(nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX]);

	dev = nfc_get_device(idx);
	if (!dev)
		return ERR_PTR(-ENODEV);

	return dev;
}

static int nfc_genl_dump_targets(struct sk_buff *skb,
				 struct netlink_callback *cb)
{
	int i = cb->args[0];
	struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
	int rc;

	if (!dev) {
		dev = __get_device_from_cb(cb);
		if (IS_ERR(dev))
			return PTR_ERR(dev);

		cb->args[1] = (long) dev;
	}

	device_lock(&dev->dev);

	cb->seq = dev->targets_generation;

	while (i < dev->n_targets) {
		rc = nfc_genl_send_target(skb, &dev->targets[i], cb,
					  NLM_F_MULTI);
		if (rc < 0)
			break;

		i++;
	}

	device_unlock(&dev->dev);

	cb->args[0] = i;

	return skb->len;
}

static int nfc_genl_dump_targets_done(struct netlink_callback *cb)
{
	struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];

	if (dev)
		nfc_put_device(dev);

	return 0;
}

int nfc_genl_targets_found(struct nfc_dev *dev