[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 u8 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) & 0x7f;
}

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
		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_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;
		case LLCP_TLV_RW:
			local->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("version 0x%x miu %d lto %d opt 0x%x wks 0x%x rw %d\n",
		 local->remote_version, local->remote_miu,
		 local->remote_lto, local->remote_opt,
		 local->remote_wks, local->remote_rw);

	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;
	u16 size = 0;

	pr_debug("Sending DISC\n");

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

	dev = sock->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_ATOMIC);
	if (skb == NULL)
		return -ENOMEM;

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

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

	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);

	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;
	__be16 miux;
	int err;
	u16 size = 0;

	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;
	}

	miux = cpu_to_be16(LLCP_MAX_MIUX);
	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
				      &miux_tlv_length);
	size += miux_tlv_length;

	rw = LLCP_MAX_RW;
	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;
	__be16 miux;
	int err;
	u16 size = 0;

	pr_debug("Sending CC\n");

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

	miux = cpu_to_be16(LLCP_MAX_MIUX);
	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
				      &miux_tlv_length);
	size += miux_tlv_length;

	rw = LLCP_MAX_RW;
	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_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, ssap, dsap, 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;

	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, local->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_head(&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 0;
}

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 % 16;

	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
	54	static u8 llcp_tlv16(u8 *tlv, u8 type)
	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	{
70	return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7f;
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;
105	else
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
120	int nfc_llcp_parse_tlv(struct nfc_llcp_local *local,
427a2eb1	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;
	152	case LLCP_TLV_RW:
	153	local->remote_rw = llcp_tlv_rw(tlv);
	154	break;
9dda50f4 SO	155	case LLCP_TLV_SN:
9dda50f4 SO	156	break;
d646960f SO	157	default:
	158	pr_err("Invalid gt tlv value 0x%x\n", type);
	159	break;
	160	}
	161
	162	offset += length + 2;
	163	tlv += length + 2;
	164	}
	165
	166	pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x rw %d\n",
427a2eb1 SO	167	local->remote_version, local->remote_miu,
	168	local->remote_lto, local->remote_opt,
	169	local->remote_wks, local->remote_rw);
d646960f SO	170
	171	return 0;
	172	}
	173
	174	static struct sk_buff llcp_add_header(struct sk_buff pdu,
427a2eb1	175	u8 dsap, u8 ssap, u8 ptype)
d646960f SO	176	{
	177	u8 header[2];
	178
	179	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
	180
	181	header[0] = (u8)((dsap << 2) \| (ptype >> 2));
	182	header[1] = (u8)((ptype << 6) \| ssap);
	183
	184	pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
	185
	186	memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
	187
	188	return pdu;
	189	}
	190
427a2eb1 SO	191	static struct sk_buff llcp_add_tlv(struct sk_buff pdu, u8 *tlv,
427a2eb1 SO	192	u8 tlv_length)
d646960f SO	193	{
	194	/* XXX Add an skb length check */
	195
	196	if (tlv == NULL)
	197	return NULL;
	198
	199	memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
	200
	201	return pdu;
	202	}
	203
	204	static struct sk_buff llcp_allocate_pdu(struct nfc_llcp_sock sock,
427a2eb1	205	u8 cmd, u16 size)
d646960f SO	206	{
	207	struct sk_buff *skb;
	208	int err;
	209
	210	if (sock->ssap == 0)
	211	return NULL;
	212
	213	skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
427a2eb1	214	size + LLCP_HEADER_SIZE, &err);
d646960f SO	215	if (skb == NULL) {
	216	pr_err("Could not allocate PDU\n");
	217	return NULL;
	218	}
	219
	220	skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
	221
	222	return skb;
	223	}
	224
	225	int nfc_llcp_disconnect(struct nfc_llcp_sock *sock)
	226	{
	227	struct sk_buff *skb;
	228	struct nfc_dev *dev;
	229	struct nfc_llcp_local *local;
	230	u16 size = 0;
	231
	232	pr_debug("Sending DISC\n");
	233
	234	local = sock->local;
	235	if (local == NULL)
	236	return -ENODEV;
	237
	238	dev = sock->dev;
	239	if (dev == NULL)
	240	return -ENODEV;
	241
	242	size += LLCP_HEADER_SIZE;
	243	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	244
	245	skb = alloc_skb(size, GFP_ATOMIC);
	246	if (skb == NULL)
	247	return -ENOMEM;
	248
	249	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	250
	251	skb = llcp_add_header(skb, sock->ssap, sock->dsap, LLCP_PDU_DISC);
	252
	253	skb_queue_tail(&local->tx_queue, skb);
	254
	255	return 0;
	256	}
	257
	258	int nfc_llcp_send_symm(struct nfc_dev *dev)
	259	{
	260	struct sk_buff *skb;
	261	struct nfc_llcp_local *local;
	262	u16 size = 0;
	263
	264	pr_debug("Sending SYMM\n");
	265
	266	local = nfc_llcp_find_local(dev);
	267	if (local == NULL)
	268	return -ENODEV;
	269
	270	size += LLCP_HEADER_SIZE;
	271	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	272
	273	skb = alloc_skb(size, GFP_KERNEL);
	274	if (skb == NULL)
	275	return -ENOMEM;
	276
	277	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	278
279	skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
280
281	return nfc_data_exchange(dev, local->target_idx, skb,
427a2eb1	282	nfc_llcp_recv, local);
d646960f SO	283	}
	284
	285	int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
	286	{
	287	struct nfc_llcp_local *local;
	288	struct sk_buff *skb;
	289	u8 *service_name_tlv = NULL, service_name_tlv_length;
eda21f16 SO	290	u8 *miux_tlv = NULL, miux_tlv_length;
	291	u8 *rw_tlv = NULL, rw_tlv_length, rw;
	292	__be16 miux;
d646960f SO	293	int err;
	294	u16 size = 0;
	295
	296	pr_debug("Sending CONNECT\n");
	297
	298	local = sock->local;
	299	if (local == NULL)
	300	return -ENODEV;
	301
	302	if (sock->service_name != NULL) {
	303	service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
427a2eb1 SO	304	sock->service_name,
	305	sock->service_name_len,
	306	&service_name_tlv_length);
d646960f SO	307	size += service_name_tlv_length;
	308	}
	309
eda21f16	310	miux = cpu_to_be16(LLCP_MAX_MIUX);
427a2eb1 SO	311	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1 SO	312	&miux_tlv_length);
eda21f16 SO	313	size += miux_tlv_length;
	314
	315	rw = LLCP_MAX_RW;
	316	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
	317	size += rw_tlv_length;
	318
d646960f SO	319	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
	320
	321	skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
	322	if (skb == NULL) {
	323	err = -ENOMEM;
	324	goto error_tlv;
	325	}
	326
	327	if (service_name_tlv != NULL)
	328	skb = llcp_add_tlv(skb, service_name_tlv,
427a2eb1	329	service_name_tlv_length);
d646960f	330
eda21f16 SO	331	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	332	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
	333
d646960f SO	334	skb_queue_tail(&local->tx_queue, skb);
	335
	336	return 0;
	337
	338	error_tlv:
	339	pr_err("error %d\n", err);
	340
	341	kfree(service_name_tlv);
eda21f16 SO	342	kfree(miux_tlv);
eda21f16 SO	343	kfree(rw_tlv);
d646960f SO	344
	345	return err;
	346	}
	347
	348	int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
	349	{
	350	struct nfc_llcp_local *local;
	351	struct sk_buff *skb;
eda21f16 SO	352	u8 *miux_tlv = NULL, miux_tlv_length;
	353	u8 *rw_tlv = NULL, rw_tlv_length, rw;
	354	__be16 miux;
	355	int err;
	356	u16 size = 0;
d646960f SO	357
	358	pr_debug("Sending CC\n");
	359
	360	local = sock->local;
	361	if (local == NULL)
	362	return -ENODEV;
	363
eda21f16	364	miux = cpu_to_be16(LLCP_MAX_MIUX);
427a2eb1 SO	365	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1 SO	366	&miux_tlv_length);
eda21f16 SO	367	size += miux_tlv_length;
	368
	369	rw = LLCP_MAX_RW;
	370	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
	371	size += rw_tlv_length;
	372
	373	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
	374	if (skb == NULL) {
	375	err = -ENOMEM;
	376	goto error_tlv;
	377	}
	378
	379	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	380	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
d646960f SO	381
	382	skb_queue_tail(&local->tx_queue, skb);
	383
	384	return 0;
eda21f16 SO	385
	386	error_tlv:
	387	pr_err("error %d\n", err);
	388
	389	kfree(miux_tlv);
	390	kfree(rw_tlv);
	391
	392	return err;
d646960f SO	393	}
	394
	395	int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
	396	{
	397	struct sk_buff *skb;
	398	struct nfc_dev *dev;
	399	u16 size = 1; /* Reason code */
	400
	401	pr_debug("Sending DM reason 0x%x\n", reason);
	402
	403	if (local == NULL)
	404	return -ENODEV;
	405
	406	dev = local->dev;
	407	if (dev == NULL)
	408	return -ENODEV;
	409
	410	size += LLCP_HEADER_SIZE;
	411	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	412
	413	skb = alloc_skb(size, GFP_KERNEL);
	414	if (skb == NULL)
	415	return -ENOMEM;
	416
	417	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	418
	419	skb = llcp_add_header(skb, ssap, dsap, LLCP_PDU_DM);
	420
	421	memcpy(skb_put(skb, 1), &reason, 1);
	422
	423	skb_queue_head(&local->tx_queue, skb);
	424
	425	return 0;
	426	}
	427
	428	int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
	429	{
	430	struct sk_buff *skb;
	431	struct nfc_llcp_local *local;
	432
	433	pr_debug("Send DISC\n");
	434
	435	local = sock->local;
	436	if (local == NULL)
	437	return -ENODEV;
	438
	439	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
	440	if (skb == NULL)
	441	return -ENOMEM;
	442
	443	skb_queue_head(&local->tx_queue, skb);
	444
	445	return 0;
	446	}
53a0ac2e SO	447
53a0ac2e SO	448	int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
427a2eb1	449	struct msghdr *msg, size_t len)
53a0ac2e SO	450	{
53a0ac2e SO	451	struct sk_buff *pdu;
e65b0f46 SO	452	struct sock *sk = &sock->sk;
	453	struct nfc_llcp_local *local;
	454	size_t frag_len = 0, remaining_len;
	455	u8 msg_data, msg_ptr;
53a0ac2e	456
e65b0f46	457	pr_debug("Send I frame len %zd\n", len);
53a0ac2e	458
e65b0f46 SO	459	local = sock->local;
	460	if (local == NULL)
	461	return -ENODEV;
53a0ac2e	462
e65b0f46 SO	463	msg_data = kzalloc(len, GFP_KERNEL);
	464	if (msg_data == NULL)
	465	return -ENOMEM;
53a0ac2e	466
e65b0f46	467	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
427a2eb1 SO	468	kfree(msg_data);
427a2eb1 SO	469	return -EFAULT;
53a0ac2e SO	470	}
53a0ac2e SO	471
e65b0f46 SO	472	remaining_len = len;
	473	msg_ptr = msg_data;
	474
	475	while (remaining_len > 0) {
	476
b4838d12	477	frag_len = min_t(size_t, local->remote_miu, remaining_len);
53a0ac2e	478
e65b0f46 SO	479	pr_debug("Fragment %zd bytes remaining %zd",
e65b0f46 SO	480	frag_len, remaining_len);
53a0ac2e	481
e65b0f46 SO	482	pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
	483	frag_len + LLCP_SEQUENCE_SIZE);
	484	if (pdu == NULL)
	485	return -ENOMEM;
	486
	487	skb_put(pdu, LLCP_SEQUENCE_SIZE);
	488
	489	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	490
	491	skb_queue_head(&sock->tx_queue, pdu);
	492
	493	lock_sock(sk);
	494
	495	nfc_llcp_queue_i_frames(sock);
	496
	497	release_sock(sk);
	498
	499	remaining_len -= frag_len;
b4838d12	500	msg_ptr += frag_len;
e65b0f46	501	}
53a0ac2e	502
e65b0f46	503	kfree(msg_data);
53a0ac2e SO	504
	505	return 0;
	506	}
d094afa1 SO	507
	508	int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
	509	{
	510	struct sk_buff *skb;
	511	struct nfc_llcp_local *local;
	512
	513	pr_debug("Send rr nr %d\n", sock->recv_n);
	514
	515	local = sock->local;
	516	if (local == NULL)
	517	return -ENODEV;
	518
	519	skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
	520	if (skb == NULL)
	521	return -ENOMEM;
	522
	523	skb_put(skb, LLCP_SEQUENCE_SIZE);
	524
	525	skb->data[2] = sock->recv_n % 16;
	526
	527	skb_queue_head(&local->tx_queue, skb);
	528
	529	return 0;
	530	}