[deliverable/linux.git] / net / nfc / llcp / commands.c

/*
 * Copyright (C) 2011  Intel Corporation. All rights reserved.
 *
 * 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) "llcp: %s: " fmt, __func__

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/nfc.h>

#include <net/nfc/nfc.h>

#include "../nfc.h"
#include "llcp.h"

static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
	0,
	1, /* VERSION */
	2, /* MIUX */
	2, /* WKS */
	1, /* LTO */
	1, /* RW */
	0, /* SN */
	1, /* OPT */
	0, /* SDREQ */
	2, /* SDRES */

};

static u8 llcp_tlv8(u8 *tlv, u8 type)
{
	if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
		return 0;

	return tlv[2];
}

static u16 llcp_tlv16(u8 *tlv, u8 type)
{
	if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
		return 0;

	return be16_to_cpu(*((__be16 *)(tlv + 2)));
}


static u8 llcp_tlv_version(u8 *tlv)
{
	return llcp_tlv8(tlv, LLCP_TLV_VERSION);
}

static u16 llcp_tlv_miux(u8 *tlv)
{
	return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
}

static u16 llcp_tlv_wks(u8 *tlv)
{
	return llcp_tlv16(tlv, LLCP_TLV_WKS);
}

static u16 llcp_tlv_lto(u8 *tlv)
{
	return llcp_tlv8(tlv, LLCP_TLV_LTO);
}

static u8 llcp_tlv_opt(u8 *tlv)
{
	return llcp_tlv8(tlv, LLCP_TLV_OPT);
}

static u8 llcp_tlv_rw(u8 *tlv)
{
	return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
}

u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length)
{
	u8 *tlv, length;

	pr_debug("type %d\n", type);

	if (type >= LLCP_TLV_MAX)
		return NULL;

	length = llcp_tlv_length[type];
	if (length == 0 && value_length == 0)
		return NULL;
	else if (length == 0)
		length = value_length;

	*tlv_length = 2 + length;
	tlv = kzalloc(2 + length, GFP_KERNEL);
	if (tlv == NULL)
		return tlv;

	tlv[0] = type;
	tlv[1] = length;
	memcpy(tlv + 2, value, length);

	return tlv;
}

int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
			  u8 *tlv_array, u16 tlv_array_len)
{
	u8 *tlv = tlv_array, type, length, offset = 0;

	pr_debug("TLV array length %d\n", tlv_array_len);

	if (local == NULL)
		return -ENODEV;

	while (offset < tlv_array_len) {
		type = tlv[0];
		length = tlv[1];

		pr_debug("type 0x%x length %d\n", type, length);

		switch (type) {
		case LLCP_TLV_VERSION:
			local->remote_version = llcp_tlv_version(tlv);
			break;
		case LLCP_TLV_MIUX:
			local->remote_miu = llcp_tlv_miux(tlv) + 128;
			break;
		case LLCP_TLV_WKS:
			local->remote_wks = llcp_tlv_wks(tlv);
			break;
		case LLCP_TLV_LTO:
			local->remote_lto = llcp_tlv_lto(tlv) * 10;
			break;
		case LLCP_TLV_OPT:
			local->remote_opt = llcp_tlv_opt(tlv);
			break;
		default:
			pr_err("Invalid gt tlv value 0x%x\n", type);
			break;
		}

		offset += length + 2;
		tlv += length + 2;
	}

	pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
		 local->remote_version, local->remote_miu,
		 local->remote_lto, local->remote_opt,
		 local->remote_wks);

	return 0;
}

int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
				  u8 *tlv_array, u16 tlv_array_len)
{
	u8 *tlv = tlv_array, type, length, offset = 0;

	pr_debug("TLV array length %d\n", tlv_array_len);

	if (sock == NULL)
		return -ENOTCONN;

	while (offset < tlv_array_len) {
		type = tlv[0];
		length = tlv[1];

		pr_debug("type 0x%x length %d\n", type, length);

		switch (type) {
		case LLCP_TLV_MIUX:
			sock->remote_miu = llcp_tlv_miux(tlv) + 128;
			break;
		case LLCP_TLV_RW:
			sock->remote_rw = llcp_tlv_rw(tlv);
			break;
		case LLCP_TLV_SN:
			break;
		default:
			pr_err("Invalid gt tlv value 0x%x\n", type);
			break;
		}

		offset += length + 2;
		tlv += length + 2;
	}

	pr_debug("sock %p rw %d miu %d\n", sock,
		 sock->remote_rw, sock->remote_miu);

	return 0;
}

static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
				       u8 dsap, u8 ssap, u8 ptype)
{
	u8 header[2];

	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);

	header[0] = (u8)((dsap << 2) | (ptype >> 2));
	header[1] = (u8)((ptype << 6) | ssap);

	pr_debug("header 0x%x 0x%x\n", header[0], header[1]);

	memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);

	return pdu;
}

static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
				    u8 tlv_length)
{
	/* XXX Add an skb length check */

	if (tlv == NULL)
		return NULL;

	memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);

	return pdu;
}

static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
					 u8 cmd, u16 size)
{
	struct sk_buff *skb;
	int err;

	if (sock->ssap == 0)
		return NULL;

	skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
				 size + LLCP_HEADER_SIZE, &err);
	if (skb == NULL) {
		pr_err("Could not allocate PDU\n");
		return NULL;
	}

	skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);

	return skb;
}

int nfc_llcp_disconnect(struct nfc_llcp_sock *sock)
{
	struct sk_buff *skb;
	struct nfc_dev *dev;
	struct nfc_llcp_local *local;

	pr_debug("Sending DISC\n");

	local = sock->local;
	if (local == NULL)
		return -ENODEV;

	dev = sock->dev;
	if (dev == NULL)
		return -ENODEV;

	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
	if (skb == NULL)
		return -ENOMEM;

	skb_queue_tail(&local->tx_queue, skb);

	return 0;
}

int nfc_llcp_send_symm(struct nfc_dev *dev)
{
	struct sk_buff *skb;
	struct nfc_llcp_local *local;
	u16 size = 0;

	pr_debug("Sending SYMM\n");

	local = nfc_llcp_find_local(dev);
	if (local == NULL)
		return -ENODEV;

	size += LLCP_HEADER_SIZE;
	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;

	skb = alloc_skb(size, GFP_KERNEL);
	if (skb == NULL)
		return -ENOMEM;

	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);

	skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);

	__net_timestamp(skb);

	nfc_llcp_send_to_raw_sock(local, skb, NFC_LLCP_DIRECTION_TX);

	return nfc_data_exchange(dev, local->target_idx, skb,
				 nfc_llcp_recv, local);
}

int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
{
	struct nfc_llcp_local *local;
	struct sk_buff *skb;
	u8 *service_name_tlv = NULL, service_name_tlv_length;
	u8 *miux_tlv = NULL, miux_tlv_length;
	u8 *rw_tlv = NULL, rw_tlv_length, rw;
	int err;
	u16 size = 0, miux;

	pr_debug("Sending CONNECT\n");

	local = sock->local;
	if (local == NULL)
		return -ENODEV;

	if (sock->service_name != NULL) {
		service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
						      sock->service_name,
						      sock->service_name_len,
						      &service_name_tlv_length);
		size += service_name_tlv_length;
	}

	/* If the socket parameters are not set, use the local ones */
	miux = sock->miux > LLCP_MAX_MIUX ? local->miux : sock->miux;
	rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;

	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
				      &miux_tlv_length);
	size += miux_tlv_length;

	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
	size += rw_tlv_length;

	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);

	skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
	if (skb == NULL) {
		err = -ENOMEM;
		goto error_tlv;
	}

	if (service_name_tlv != NULL)
		skb = llcp_add_tlv(skb, service_name_tlv,
				   service_name_tlv_length);

	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);

	skb_queue_tail(&local->tx_queue, skb);

	return 0;

error_tlv:
	pr_err("error %d\n", err);

	kfree(service_name_tlv);
	kfree(miux_tlv);
	kfree(rw_tlv);

	return err;
}

int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
{
	struct nfc_llcp_local *local;
	struct sk_buff *skb;
	u8 *miux_tlv = NULL, miux_tlv_length;
	u8 *rw_tlv = NULL, rw_tlv_length, rw;
	int err;
	u16 size = 0, miux;

	pr_debug("Sending CC\n");

	local = sock->local;
	if (local == NULL)
		return -ENODEV;

	/* If the socket parameters are not set, use the local ones */
	miux = sock->miux > LLCP_MAX_MIUX ? local->miux : sock->miux;
	rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;

	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
				      &miux_tlv_length);
	size += miux_tlv_length;

	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
	size += rw_tlv_length;

	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
	if (skb == NULL) {
		err = -ENOMEM;
		goto error_tlv;
	}

	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);

	skb_queue_tail(&local->tx_queue, skb);

	return 0;

error_tlv:
	pr_err("error %d\n", err);

	kfree(miux_tlv);
	kfree(rw_tlv);

	return err;
}

int nfc_llcp_send_snl(struct nfc_llcp_local *local, u8 tid, u8 sap)
{
	struct sk_buff *skb;
	struct nfc_dev *dev;
	u8 *sdres_tlv = NULL, sdres_tlv_length, sdres[2];
	u16 size = 0;

	pr_debug("Sending SNL tid 0x%x sap 0x%x\n", tid, sap);

	if (local == NULL)
		return -ENODEV;

	dev = local->dev;
	if (dev == NULL)
		return -ENODEV;

	sdres[0] = tid;
	sdres[1] = sap;
	sdres_tlv = nfc_llcp_build_tlv(LLCP_TLV_SDRES, sdres, 0,
				       &sdres_tlv_length);
	if (sdres_tlv == NULL)
		return -ENOMEM;

	size += LLCP_HEADER_SIZE;
	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	size += sdres_tlv_length;

	skb = alloc_skb(size, GFP_KERNEL);
	if (skb == NULL) {
		kfree(sdres_tlv);
		return -ENOMEM;
	}

	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);

	skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);

	memcpy(skb_put(skb, sdres_tlv_length), sdres_tlv, sdres_tlv_length);

	skb_queue_tail(&local->tx_queue, skb);

	kfree(sdres_tlv);

	return 0;
}

int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
{
	struct sk_buff *skb;
	struct nfc_dev *dev;
	u16 size = 1; /* Reason code */

	pr_debug("Sending DM reason 0x%x\n", reason);

	if (local == NULL)
		return -ENODEV;

	dev = local->dev;
	if (dev == NULL)
		return -ENODEV;

	size += LLCP_HEADER_SIZE;
	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;

	skb = alloc_skb(size, GFP_KERNEL);
	if (skb == NULL)
		return -ENOMEM;

	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);

	skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);

	memcpy(skb_put(skb, 1), &reason, 1);

	skb_queue_head(&local->tx_queue, skb);

	return 0;
}

int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
{
	struct sk_buff *skb;
	struct nfc_llcp_local *local;

	pr_debug("Send DISC\n");

	local = sock->local;
	if (local == NULL)
		return -ENODEV;

	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
	if (skb == NULL)
		return -ENOMEM;

	skb_queue_head(&local->tx_queue, skb);

	return 0;
}

int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
			  struct msghdr *msg, size_t len)
{
	struct sk_buff *pdu;
	struct sock *sk = &sock->sk;
	struct nfc_llcp_local *local;
	size_t frag_len = 0, remaining_len;
	u8 *msg_data, *msg_ptr;

	pr_debug("Send I frame len %zd\n", len);

	local = sock->local;
	if (local == NULL)
		return -ENODEV;

	/* Remote is ready but has not acknowledged our frames */
	if((sock->remote_ready &&
	    skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
	    skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
		pr_err("Pending queue is full %d frames\n",
		       skb_queue_len(&sock->tx_pending_queue));
		return -ENOBUFS;
	}

	/* Remote is not ready and we've been queueing enough frames */
	if ((!sock->remote_ready &&
	     skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
		pr_err("Tx queue is full %d frames\n",
		       skb_queue_len(&sock->tx_queue));
		return -ENOBUFS;
	}

	msg_data = kzalloc(len, GFP_KERNEL);
	if (msg_data == NULL)
		return -ENOMEM;

	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
		kfree(msg_data);
		return -EFAULT;
	}

	remaining_len = len;
	msg_ptr = msg_data;

	while (remaining_len > 0) {

		frag_len = min_t(size_t, sock->remote_miu, remaining_len);

		pr_debug("Fragment %zd bytes remaining %zd",
			 frag_len, remaining_len);

		pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
					frag_len + LLCP_SEQUENCE_SIZE);
		if (pdu == NULL)
			return -ENOMEM;

		skb_put(pdu, LLCP_SEQUENCE_SIZE);

		memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);

		skb_queue_tail(&sock->tx_queue, pdu);

		lock_sock(sk);

		nfc_llcp_queue_i_frames(sock);

		release_sock(sk);

		remaining_len -= frag_len;
		msg_ptr += frag_len;
	}

	kfree(msg_data);

	return len;
}

int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
			   struct msghdr *msg, size_t len)
{
	struct sk_buff *pdu;
	struct nfc_llcp_local *local;
	size_t frag_len = 0, remaining_len;
	u8 *msg_ptr, *msg_data;
	int err;

	pr_debug("Send UI frame len %zd\n", len);

	local = sock->local;
	if (local == NULL)
		return -ENODEV;

	msg_data = kzalloc(len, GFP_KERNEL);
	if (msg_data == NULL)
		return -ENOMEM;

	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
		kfree(msg_data);
		return -EFAULT;
	}

	remaining_len = len;
	msg_ptr = msg_data;

	while (remaining_len > 0) {

		frag_len = min_t(size_t, sock->remote_miu, remaining_len);

		pr_debug("Fragment %zd bytes remaining %zd",
			 frag_len, remaining_len);

		pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
					 frag_len + LLCP_HEADER_SIZE, &err);
		if (pdu == NULL) {
			pr_err("Could not allocate PDU\n");
			continue;
		}

		pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);

		memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);

		/* No need to check for the peer RW for UI frames */
		skb_queue_tail(&local->tx_queue, pdu);

		remaining_len -= frag_len;
		msg_ptr += frag_len;
	}

	kfree(msg_data);

	return len;
}

int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
{
	struct sk_buff *skb;
	struct nfc_llcp_local *local;

	pr_debug("Send rr nr %d\n", sock->recv_n);

	local = sock->local;
	if (local == NULL)
		return -ENODEV;

	skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
	if (skb == NULL)
		return -ENOMEM;

	skb_put(skb, LLCP_SEQUENCE_SIZE);

	skb->data[2] = sock->recv_n;

	skb_queue_head(&local->tx_queue, skb);

	return 0;
}
Commit	Line	Data
d646960f SO	1	/*
	2	* Copyright (C) 2011 Intel Corporation. All rights reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation; either version 2 of the License, or
	7	* (at your option) any later version.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write to the
	16	* Free Software Foundation, Inc.,
	17	* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	18	*/
	19
	20	#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
	21
	22	#include <linux/init.h>
	23	#include <linux/kernel.h>
	24	#include <linux/module.h>
	25	#include <linux/nfc.h>
	26
	27	#include <net/nfc/nfc.h>
	28
	29	#include "../nfc.h"
	30	#include "llcp.h"
	31
	32	static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
	33	0,
	34	1, /* VERSION */
	35	2, /* MIUX */
	36	2, /* WKS */
	37	1, /* LTO */
	38	1, /* RW */
	39	0, /* SN */
	40	1, /* OPT */
	41	0, /* SDREQ */
	42	2, /* SDRES */
	43
	44	};
	45
	46	static u8 llcp_tlv8(u8 *tlv, u8 type)
	47	{
	48	if (tlv[0] != type \|\| tlv[1] != llcp_tlv_length[tlv[0]])
	49	return 0;
	50
	51	return tlv[2];
	52	}
	53
76762b73	54	static u16 llcp_tlv16(u8 *tlv, u8 type)
d646960f SO	55	{
	56	if (tlv[0] != type \|\| tlv[1] != llcp_tlv_length[tlv[0]])
	57	return 0;
	58
	59	return be16_to_cpu(((__be16 )(tlv + 2)));
	60	}
	61
	62
	63	static u8 llcp_tlv_version(u8 *tlv)
	64	{
	65	return llcp_tlv8(tlv, LLCP_TLV_VERSION);
	66	}
	67
	68	static u16 llcp_tlv_miux(u8 *tlv)
	69	{
76762b73	70	return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7ff;
d646960f SO	71	}
	72
	73	static u16 llcp_tlv_wks(u8 *tlv)
	74	{
	75	return llcp_tlv16(tlv, LLCP_TLV_WKS);
	76	}
	77
	78	static u16 llcp_tlv_lto(u8 *tlv)
	79	{
	80	return llcp_tlv8(tlv, LLCP_TLV_LTO);
	81	}
	82
	83	static u8 llcp_tlv_opt(u8 *tlv)
	84	{
	85	return llcp_tlv8(tlv, LLCP_TLV_OPT);
	86	}
	87
	88	static u8 llcp_tlv_rw(u8 *tlv)
	89	{
	90	return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
	91	}
	92
	93	u8 nfc_llcp_build_tlv(u8 type, u8 value, u8 value_length, u8 *tlv_length)
	94	{
	95	u8 *tlv, length;
	96
	97	pr_debug("type %d\n", type);
	98
	99	if (type >= LLCP_TLV_MAX)
	100	return NULL;
	101
	102	length = llcp_tlv_length[type];
	103	if (length == 0 && value_length == 0)
	104	return NULL;
324b0af6	105	else if (length == 0)
d646960f SO	106	length = value_length;
	107
	108	*tlv_length = 2 + length;
	109	tlv = kzalloc(2 + length, GFP_KERNEL);
	110	if (tlv == NULL)
	111	return tlv;
	112
	113	tlv[0] = type;
	114	tlv[1] = length;
	115	memcpy(tlv + 2, value, length);
	116
	117	return tlv;
	118	}
	119
7a06e586 SO	120	int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
7a06e586 SO	121	u8 *tlv_array, u16 tlv_array_len)
d646960f SO	122	{
	123	u8 *tlv = tlv_array, type, length, offset = 0;
	124
	125	pr_debug("TLV array length %d\n", tlv_array_len);
	126
	127	if (local == NULL)
	128	return -ENODEV;
	129
	130	while (offset < tlv_array_len) {
	131	type = tlv[0];
	132	length = tlv[1];
	133
	134	pr_debug("type 0x%x length %d\n", type, length);
	135
	136	switch (type) {
	137	case LLCP_TLV_VERSION:
	138	local->remote_version = llcp_tlv_version(tlv);
	139	break;
	140	case LLCP_TLV_MIUX:
	141	local->remote_miu = llcp_tlv_miux(tlv) + 128;
	142	break;
	143	case LLCP_TLV_WKS:
	144	local->remote_wks = llcp_tlv_wks(tlv);
	145	break;
	146	case LLCP_TLV_LTO:
	147	local->remote_lto = llcp_tlv_lto(tlv) * 10;
	148	break;
	149	case LLCP_TLV_OPT:
	150	local->remote_opt = llcp_tlv_opt(tlv);
	151	break;
7a06e586 SO	152	default:
	153	pr_err("Invalid gt tlv value 0x%x\n", type);
	154	break;
	155	}
	156
	157	offset += length + 2;
	158	tlv += length + 2;
	159	}
	160
	161	pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
	162	local->remote_version, local->remote_miu,
	163	local->remote_lto, local->remote_opt,
	164	local->remote_wks);
	165
	166	return 0;
	167	}
	168
	169	int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
	170	u8 *tlv_array, u16 tlv_array_len)
	171	{
	172	u8 *tlv = tlv_array, type, length, offset = 0;
	173
	174	pr_debug("TLV array length %d\n", tlv_array_len);
	175
	176	if (sock == NULL)
	177	return -ENOTCONN;
	178
	179	while (offset < tlv_array_len) {
	180	type = tlv[0];
	181	length = tlv[1];
	182
	183	pr_debug("type 0x%x length %d\n", type, length);
	184
	185	switch (type) {
93d7e490	186	case LLCP_TLV_MIUX:
e4306bec	187	sock->remote_miu = llcp_tlv_miux(tlv) + 128;
93d7e490	188	break;
d646960f	189	case LLCP_TLV_RW:
e4306bec	190	sock->remote_rw = llcp_tlv_rw(tlv);
d646960f	191	break;
9dda50f4 SO	192	case LLCP_TLV_SN:
9dda50f4 SO	193	break;
d646960f SO	194	default:
	195	pr_err("Invalid gt tlv value 0x%x\n", type);
	196	break;
	197	}
	198
	199	offset += length + 2;
	200	tlv += length + 2;
	201	}
	202
e4306bec SO	203	pr_debug("sock %p rw %d miu %d\n", sock,
e4306bec SO	204	sock->remote_rw, sock->remote_miu);
d646960f SO	205
	206	return 0;
	207	}
	208
	209	static struct sk_buff llcp_add_header(struct sk_buff pdu,
427a2eb1	210	u8 dsap, u8 ssap, u8 ptype)
d646960f SO	211	{
	212	u8 header[2];
	213
	214	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
	215
	216	header[0] = (u8)((dsap << 2) \| (ptype >> 2));
	217	header[1] = (u8)((ptype << 6) \| ssap);
	218
	219	pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
	220
	221	memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
	222
	223	return pdu;
	224	}
	225
427a2eb1 SO	226	static struct sk_buff llcp_add_tlv(struct sk_buff pdu, u8 *tlv,
427a2eb1 SO	227	u8 tlv_length)
d646960f SO	228	{
	229	/* XXX Add an skb length check */
	230
	231	if (tlv == NULL)
	232	return NULL;
	233
	234	memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
	235
	236	return pdu;
	237	}
	238
	239	static struct sk_buff llcp_allocate_pdu(struct nfc_llcp_sock sock,
427a2eb1	240	u8 cmd, u16 size)
d646960f SO	241	{
	242	struct sk_buff *skb;
	243	int err;
	244
	245	if (sock->ssap == 0)
	246	return NULL;
	247
	248	skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
427a2eb1	249	size + LLCP_HEADER_SIZE, &err);
d646960f SO	250	if (skb == NULL) {
	251	pr_err("Could not allocate PDU\n");
	252	return NULL;
	253	}
	254
	255	skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
	256
	257	return skb;
	258	}
	259
	260	int nfc_llcp_disconnect(struct nfc_llcp_sock *sock)
	261	{
	262	struct sk_buff *skb;
	263	struct nfc_dev *dev;
	264	struct nfc_llcp_local *local;
d646960f SO	265
	266	pr_debug("Sending DISC\n");
	267
	268	local = sock->local;
	269	if (local == NULL)
	270	return -ENODEV;
	271
	272	dev = sock->dev;
	273	if (dev == NULL)
	274	return -ENODEV;
	275
92223906	276	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
d646960f SO	277	if (skb == NULL)
	278	return -ENOMEM;
	279
d646960f SO	280	skb_queue_tail(&local->tx_queue, skb);
	281
	282	return 0;
	283	}
	284
	285	int nfc_llcp_send_symm(struct nfc_dev *dev)
	286	{
	287	struct sk_buff *skb;
	288	struct nfc_llcp_local *local;
	289	u16 size = 0;
	290
	291	pr_debug("Sending SYMM\n");
	292
	293	local = nfc_llcp_find_local(dev);
	294	if (local == NULL)
	295	return -ENODEV;
	296
	297	size += LLCP_HEADER_SIZE;
	298	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	299
	300	skb = alloc_skb(size, GFP_KERNEL);
	301	if (skb == NULL)
	302	return -ENOMEM;
	303
	304	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	305
	306	skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
	307
2c2d45bd TE	308	__net_timestamp(skb);
2c2d45bd TE	309
4463523b TE	310	nfc_llcp_send_to_raw_sock(local, skb, NFC_LLCP_DIRECTION_TX);
4463523b TE	311
d646960f	312	return nfc_data_exchange(dev, local->target_idx, skb,
427a2eb1	313	nfc_llcp_recv, local);
d646960f SO	314	}
	315
	316	int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
	317	{
	318	struct nfc_llcp_local *local;
	319	struct sk_buff *skb;
	320	u8 *service_name_tlv = NULL, service_name_tlv_length;
eda21f16	321	u8 *miux_tlv = NULL, miux_tlv_length;
06d44f80	322	u8 *rw_tlv = NULL, rw_tlv_length, rw;
d646960f	323	int err;
06d44f80	324	u16 size = 0, miux;
d646960f SO	325
	326	pr_debug("Sending CONNECT\n");
	327
	328	local = sock->local;
	329	if (local == NULL)
	330	return -ENODEV;
	331
	332	if (sock->service_name != NULL) {
	333	service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
427a2eb1 SO	334	sock->service_name,
	335	sock->service_name_len,
	336	&service_name_tlv_length);
d646960f SO	337	size += service_name_tlv_length;
	338	}
	339
06d44f80 SO	340	/* If the socket parameters are not set, use the local ones */
	341	miux = sock->miux > LLCP_MAX_MIUX ? local->miux : sock->miux;
	342	rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
	343
	344	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1	345	&miux_tlv_length);
eda21f16 SO	346	size += miux_tlv_length;
eda21f16 SO	347
06d44f80	348	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
eda21f16 SO	349	size += rw_tlv_length;
eda21f16 SO	350
d646960f SO	351	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
	352
	353	skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
	354	if (skb == NULL) {
	355	err = -ENOMEM;
	356	goto error_tlv;
	357	}
	358
	359	if (service_name_tlv != NULL)
	360	skb = llcp_add_tlv(skb, service_name_tlv,
427a2eb1	361	service_name_tlv_length);
d646960f	362
eda21f16 SO	363	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	364	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
	365
d646960f SO	366	skb_queue_tail(&local->tx_queue, skb);
	367
	368	return 0;
	369
	370	error_tlv:
	371	pr_err("error %d\n", err);
	372
	373	kfree(service_name_tlv);
eda21f16 SO	374	kfree(miux_tlv);
eda21f16 SO	375	kfree(rw_tlv);
d646960f SO	376
	377	return err;
	378	}
	379
	380	int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
	381	{
	382	struct nfc_llcp_local *local;
	383	struct sk_buff *skb;
eda21f16	384	u8 *miux_tlv = NULL, miux_tlv_length;
06d44f80	385	u8 *rw_tlv = NULL, rw_tlv_length, rw;
eda21f16	386	int err;
06d44f80	387	u16 size = 0, miux;
d646960f SO	388
	389	pr_debug("Sending CC\n");
	390
	391	local = sock->local;
	392	if (local == NULL)
	393	return -ENODEV;
	394
06d44f80 SO	395	/* If the socket parameters are not set, use the local ones */
	396	miux = sock->miux > LLCP_MAX_MIUX ? local->miux : sock->miux;
	397	rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
	398
	399	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1	400	&miux_tlv_length);
eda21f16 SO	401	size += miux_tlv_length;
eda21f16 SO	402
06d44f80	403	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
eda21f16 SO	404	size += rw_tlv_length;
	405
	406	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
	407	if (skb == NULL) {
	408	err = -ENOMEM;
	409	goto error_tlv;
	410	}
	411
	412	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	413	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
d646960f SO	414
	415	skb_queue_tail(&local->tx_queue, skb);
	416
	417	return 0;
eda21f16 SO	418
	419	error_tlv:
	420	pr_err("error %d\n", err);
	421
	422	kfree(miux_tlv);
	423	kfree(rw_tlv);
	424
	425	return err;
d646960f SO	426	}
d646960f SO	427
c43bb03d SO	428	int nfc_llcp_send_snl(struct nfc_llcp_local *local, u8 tid, u8 sap)
	429	{
	430	struct sk_buff *skb;
	431	struct nfc_dev *dev;
	432	u8 *sdres_tlv = NULL, sdres_tlv_length, sdres[2];
	433	u16 size = 0;
	434
	435	pr_debug("Sending SNL tid 0x%x sap 0x%x\n", tid, sap);
	436
	437	if (local == NULL)
	438	return -ENODEV;
	439
	440	dev = local->dev;
	441	if (dev == NULL)
	442	return -ENODEV;
	443
	444	sdres[0] = tid;
	445	sdres[1] = sap;
	446	sdres_tlv = nfc_llcp_build_tlv(LLCP_TLV_SDRES, sdres, 0,
	447	&sdres_tlv_length);
	448	if (sdres_tlv == NULL)
	449	return -ENOMEM;
	450
	451	size += LLCP_HEADER_SIZE;
	452	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	453	size += sdres_tlv_length;
	454
	455	skb = alloc_skb(size, GFP_KERNEL);
	456	if (skb == NULL) {
	457	kfree(sdres_tlv);
	458	return -ENOMEM;
	459	}
	460
	461	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	462
	463	skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
	464
	465	memcpy(skb_put(skb, sdres_tlv_length), sdres_tlv, sdres_tlv_length);
	466
	467	skb_queue_tail(&local->tx_queue, skb);
	468
	469	kfree(sdres_tlv);
	470
	471	return 0;
	472	}
	473
d646960f SO	474	int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
	475	{
	476	struct sk_buff *skb;
	477	struct nfc_dev *dev;
	478	u16 size = 1; /* Reason code */
	479
	480	pr_debug("Sending DM reason 0x%x\n", reason);
	481
	482	if (local == NULL)
	483	return -ENODEV;
	484
	485	dev = local->dev;
	486	if (dev == NULL)
	487	return -ENODEV;
	488
	489	size += LLCP_HEADER_SIZE;
	490	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	491
	492	skb = alloc_skb(size, GFP_KERNEL);
	493	if (skb == NULL)
	494	return -ENOMEM;
	495
	496	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	497
ffc29315	498	skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
d646960f SO	499
	500	memcpy(skb_put(skb, 1), &reason, 1);
	501
	502	skb_queue_head(&local->tx_queue, skb);
	503
	504	return 0;
	505	}
	506
	507	int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
	508	{
	509	struct sk_buff *skb;
	510	struct nfc_llcp_local *local;
	511
	512	pr_debug("Send DISC\n");
	513
	514	local = sock->local;
	515	if (local == NULL)
	516	return -ENODEV;
	517
	518	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
	519	if (skb == NULL)
	520	return -ENOMEM;
	521
	522	skb_queue_head(&local->tx_queue, skb);
	523
	524	return 0;
	525	}
53a0ac2e SO	526
53a0ac2e SO	527	int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
427a2eb1	528	struct msghdr *msg, size_t len)
53a0ac2e SO	529	{
53a0ac2e SO	530	struct sk_buff *pdu;
e65b0f46 SO	531	struct sock *sk = &sock->sk;
	532	struct nfc_llcp_local *local;
	533	size_t frag_len = 0, remaining_len;
	534	u8 msg_data, msg_ptr;
53a0ac2e	535
e65b0f46	536	pr_debug("Send I frame len %zd\n", len);
53a0ac2e	537
e65b0f46 SO	538	local = sock->local;
	539	if (local == NULL)
	540	return -ENODEV;
53a0ac2e	541
dd2bf43f SO	542	/* Remote is ready but has not acknowledged our frames */
dd2bf43f SO	543	if((sock->remote_ready &&
e4306bec SO	544	skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
e4306bec SO	545	skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
dd2bf43f SO	546	pr_err("Pending queue is full %d frames\n",
	547	skb_queue_len(&sock->tx_pending_queue));
	548	return -ENOBUFS;
	549	}
	550
	551	/* Remote is not ready and we've been queueing enough frames */
	552	if ((!sock->remote_ready &&
e4306bec	553	skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
dd2bf43f SO	554	pr_err("Tx queue is full %d frames\n",
	555	skb_queue_len(&sock->tx_queue));
	556	return -ENOBUFS;
	557	}
	558
e65b0f46 SO	559	msg_data = kzalloc(len, GFP_KERNEL);
	560	if (msg_data == NULL)
	561	return -ENOMEM;
53a0ac2e	562
e65b0f46	563	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
427a2eb1 SO	564	kfree(msg_data);
427a2eb1 SO	565	return -EFAULT;
53a0ac2e SO	566	}
53a0ac2e SO	567
e65b0f46 SO	568	remaining_len = len;
	569	msg_ptr = msg_data;
	570
	571	while (remaining_len > 0) {
	572
e4306bec	573	frag_len = min_t(size_t, sock->remote_miu, remaining_len);
53a0ac2e	574
e65b0f46 SO	575	pr_debug("Fragment %zd bytes remaining %zd",
e65b0f46 SO	576	frag_len, remaining_len);
53a0ac2e	577
e65b0f46 SO	578	pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
	579	frag_len + LLCP_SEQUENCE_SIZE);
	580	if (pdu == NULL)
	581	return -ENOMEM;
	582
	583	skb_put(pdu, LLCP_SEQUENCE_SIZE);
	584
	585	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	586
bdbc59b3	587	skb_queue_tail(&sock->tx_queue, pdu);
e65b0f46 SO	588
	589	lock_sock(sk);
	590
	591	nfc_llcp_queue_i_frames(sock);
	592
	593	release_sock(sk);
	594
	595	remaining_len -= frag_len;
b4838d12	596	msg_ptr += frag_len;
e65b0f46	597	}
53a0ac2e	598
e65b0f46	599	kfree(msg_data);
53a0ac2e	600
43472fff	601	return len;
53a0ac2e	602	}
d094afa1	603
94f418a2 SO	604	int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
	605	struct msghdr *msg, size_t len)
	606	{
	607	struct sk_buff *pdu;
	608	struct nfc_llcp_local *local;
	609	size_t frag_len = 0, remaining_len;
6e950fd2	610	u8 msg_ptr, msg_data;
94f418a2 SO	611	int err;
	612
	613	pr_debug("Send UI frame len %zd\n", len);
	614
	615	local = sock->local;
	616	if (local == NULL)
	617	return -ENODEV;
	618
6e950fd2 SO	619	msg_data = kzalloc(len, GFP_KERNEL);
	620	if (msg_data == NULL)
	621	return -ENOMEM;
	622
	623	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
	624	kfree(msg_data);
	625	return -EFAULT;
	626	}
	627
94f418a2	628	remaining_len = len;
6e950fd2	629	msg_ptr = msg_data;
94f418a2 SO	630
	631	while (remaining_len > 0) {
	632
e4306bec	633	frag_len = min_t(size_t, sock->remote_miu, remaining_len);
94f418a2 SO	634
	635	pr_debug("Fragment %zd bytes remaining %zd",
	636	frag_len, remaining_len);
	637
	638	pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
	639	frag_len + LLCP_HEADER_SIZE, &err);
	640	if (pdu == NULL) {
	641	pr_err("Could not allocate PDU\n");
	642	continue;
	643	}
	644
	645	pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
	646
	647	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	648
	649	/* No need to check for the peer RW for UI frames */
	650	skb_queue_tail(&local->tx_queue, pdu);
	651
	652	remaining_len -= frag_len;
	653	msg_ptr += frag_len;
	654	}
	655
6e950fd2 SO	656	kfree(msg_data);
6e950fd2 SO	657
94f418a2 SO	658	return len;
	659	}
	660
d094afa1 SO	661	int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
	662	{
	663	struct sk_buff *skb;
	664	struct nfc_llcp_local *local;
	665
	666	pr_debug("Send rr nr %d\n", sock->recv_n);
	667
	668	local = sock->local;
	669	if (local == NULL)
	670	return -ENODEV;
	671
	672	skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
	673	if (skb == NULL)
	674	return -ENOMEM;
	675
	676	skb_put(skb, LLCP_SEQUENCE_SIZE);
	677
279cf174	678	skb->data[2] = sock->recv_n;
d094afa1 SO	679
	680	skb_queue_head(&local->tx_queue, skb);
	681
	682	return 0;
	683	}