[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 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->miu = llcp_tlv_miux(tlv) + 128;
			break;
		case LLCP_TLV_RW:
			sock->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->rw, sock->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;
	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->dsap, sock->ssap, 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, 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;

	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->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_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
	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;
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 SO	186	case LLCP_TLV_MIUX:
	187	sock->miu = llcp_tlv_miux(tlv) + 128;
	188	break;
d646960f	189	case LLCP_TLV_RW:
7a06e586	190	sock->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
93d7e490	203	pr_debug("sock %p rw %d miu %d\n", sock, sock->rw, sock->miu);
d646960f SO	204
	205	return 0;
	206	}
	207
	208	static struct sk_buff llcp_add_header(struct sk_buff pdu,
427a2eb1	209	u8 dsap, u8 ssap, u8 ptype)
d646960f SO	210	{
	211	u8 header[2];
	212
	213	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
	214
	215	header[0] = (u8)((dsap << 2) \| (ptype >> 2));
	216	header[1] = (u8)((ptype << 6) \| ssap);
	217
	218	pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
	219
	220	memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
	221
	222	return pdu;
	223	}
	224
427a2eb1 SO	225	static struct sk_buff llcp_add_tlv(struct sk_buff pdu, u8 *tlv,
427a2eb1 SO	226	u8 tlv_length)
d646960f SO	227	{
	228	/* XXX Add an skb length check */
	229
	230	if (tlv == NULL)
	231	return NULL;
	232
	233	memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
	234
	235	return pdu;
	236	}
	237
	238	static struct sk_buff llcp_allocate_pdu(struct nfc_llcp_sock sock,
427a2eb1	239	u8 cmd, u16 size)
d646960f SO	240	{
	241	struct sk_buff *skb;
	242	int err;
	243
	244	if (sock->ssap == 0)
	245	return NULL;
	246
	247	skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
427a2eb1	248	size + LLCP_HEADER_SIZE, &err);
d646960f SO	249	if (skb == NULL) {
	250	pr_err("Could not allocate PDU\n");
	251	return NULL;
	252	}
	253
	254	skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
	255
	256	return skb;
	257	}
	258
	259	int nfc_llcp_disconnect(struct nfc_llcp_sock *sock)
	260	{
	261	struct sk_buff *skb;
	262	struct nfc_dev *dev;
	263	struct nfc_llcp_local *local;
	264	u16 size = 0;
	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
	276	size += LLCP_HEADER_SIZE;
	277	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	278
	279	skb = alloc_skb(size, GFP_ATOMIC);
	280	if (skb == NULL)
	281	return -ENOMEM;
	282
	283	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	284
ffc29315	285	skb = llcp_add_header(skb, sock->dsap, sock->ssap, LLCP_PDU_DISC);
d646960f SO	286
	287	skb_queue_tail(&local->tx_queue, skb);
	288
	289	return 0;
	290	}
	291
	292	int nfc_llcp_send_symm(struct nfc_dev *dev)
	293	{
	294	struct sk_buff *skb;
	295	struct nfc_llcp_local *local;
	296	u16 size = 0;
	297
	298	pr_debug("Sending SYMM\n");
	299
	300	local = nfc_llcp_find_local(dev);
	301	if (local == NULL)
	302	return -ENODEV;
	303
	304	size += LLCP_HEADER_SIZE;
	305	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	306
	307	skb = alloc_skb(size, GFP_KERNEL);
	308	if (skb == NULL)
	309	return -ENOMEM;
	310
	311	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	312
	313	skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
	314
	315	return nfc_data_exchange(dev, local->target_idx, skb,
427a2eb1	316	nfc_llcp_recv, local);
d646960f SO	317	}
	318
	319	int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
	320	{
	321	struct nfc_llcp_local *local;
	322	struct sk_buff *skb;
	323	u8 *service_name_tlv = NULL, service_name_tlv_length;
eda21f16 SO	324	u8 *miux_tlv = NULL, miux_tlv_length;
	325	u8 *rw_tlv = NULL, rw_tlv_length, rw;
	326	__be16 miux;
d646960f SO	327	int err;
	328	u16 size = 0;
	329
	330	pr_debug("Sending CONNECT\n");
	331
	332	local = sock->local;
	333	if (local == NULL)
	334	return -ENODEV;
	335
	336	if (sock->service_name != NULL) {
	337	service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
427a2eb1 SO	338	sock->service_name,
	339	sock->service_name_len,
	340	&service_name_tlv_length);
d646960f SO	341	size += service_name_tlv_length;
	342	}
	343
eda21f16	344	miux = cpu_to_be16(LLCP_MAX_MIUX);
427a2eb1 SO	345	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1 SO	346	&miux_tlv_length);
eda21f16 SO	347	size += miux_tlv_length;
	348
	349	rw = LLCP_MAX_RW;
	350	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
	351	size += rw_tlv_length;
	352
d646960f SO	353	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
	354
	355	skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
	356	if (skb == NULL) {
	357	err = -ENOMEM;
	358	goto error_tlv;
	359	}
	360
	361	if (service_name_tlv != NULL)
	362	skb = llcp_add_tlv(skb, service_name_tlv,
427a2eb1	363	service_name_tlv_length);
d646960f	364
eda21f16 SO	365	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	366	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
	367
d646960f SO	368	skb_queue_tail(&local->tx_queue, skb);
	369
	370	return 0;
	371
	372	error_tlv:
	373	pr_err("error %d\n", err);
	374
	375	kfree(service_name_tlv);
eda21f16 SO	376	kfree(miux_tlv);
eda21f16 SO	377	kfree(rw_tlv);
d646960f SO	378
	379	return err;
	380	}
	381
	382	int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
	383	{
	384	struct nfc_llcp_local *local;
	385	struct sk_buff *skb;
eda21f16 SO	386	u8 *miux_tlv = NULL, miux_tlv_length;
	387	u8 *rw_tlv = NULL, rw_tlv_length, rw;
	388	__be16 miux;
	389	int err;
	390	u16 size = 0;
d646960f SO	391
	392	pr_debug("Sending CC\n");
	393
	394	local = sock->local;
	395	if (local == NULL)
	396	return -ENODEV;
	397
eda21f16	398	miux = cpu_to_be16(LLCP_MAX_MIUX);
427a2eb1 SO	399	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1 SO	400	&miux_tlv_length);
eda21f16 SO	401	size += miux_tlv_length;
	402
	403	rw = LLCP_MAX_RW;
	404	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
	405	size += rw_tlv_length;
	406
	407	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
	408	if (skb == NULL) {
	409	err = -ENOMEM;
	410	goto error_tlv;
	411	}
	412
	413	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	414	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
d646960f SO	415
	416	skb_queue_tail(&local->tx_queue, skb);
	417
	418	return 0;
eda21f16 SO	419
	420	error_tlv:
	421	pr_err("error %d\n", err);
	422
	423	kfree(miux_tlv);
	424	kfree(rw_tlv);
	425
	426	return err;
d646960f SO	427	}
	428
	429	int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
	430	{
	431	struct sk_buff *skb;
	432	struct nfc_dev *dev;
	433	u16 size = 1; /* Reason code */
	434
	435	pr_debug("Sending DM reason 0x%x\n", reason);
	436
	437	if (local == NULL)
	438	return -ENODEV;
	439
	440	dev = local->dev;
	441	if (dev == NULL)
	442	return -ENODEV;
	443
	444	size += LLCP_HEADER_SIZE;
	445	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	446
	447	skb = alloc_skb(size, GFP_KERNEL);
	448	if (skb == NULL)
	449	return -ENOMEM;
	450
	451	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	452
ffc29315	453	skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
d646960f SO	454
	455	memcpy(skb_put(skb, 1), &reason, 1);
	456
	457	skb_queue_head(&local->tx_queue, skb);
	458
	459	return 0;
	460	}
	461
	462	int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
	463	{
	464	struct sk_buff *skb;
	465	struct nfc_llcp_local *local;
	466
	467	pr_debug("Send DISC\n");
	468
	469	local = sock->local;
	470	if (local == NULL)
	471	return -ENODEV;
	472
	473	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
	474	if (skb == NULL)
	475	return -ENOMEM;
	476
	477	skb_queue_head(&local->tx_queue, skb);
	478
	479	return 0;
	480	}
53a0ac2e SO	481
53a0ac2e SO	482	int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
427a2eb1	483	struct msghdr *msg, size_t len)
53a0ac2e SO	484	{
53a0ac2e SO	485	struct sk_buff *pdu;
e65b0f46 SO	486	struct sock *sk = &sock->sk;
	487	struct nfc_llcp_local *local;
	488	size_t frag_len = 0, remaining_len;
	489	u8 msg_data, msg_ptr;
53a0ac2e	490
e65b0f46	491	pr_debug("Send I frame len %zd\n", len);
53a0ac2e	492
e65b0f46 SO	493	local = sock->local;
	494	if (local == NULL)
	495	return -ENODEV;
53a0ac2e	496
e65b0f46 SO	497	msg_data = kzalloc(len, GFP_KERNEL);
	498	if (msg_data == NULL)
	499	return -ENOMEM;
53a0ac2e	500
e65b0f46	501	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
427a2eb1 SO	502	kfree(msg_data);
427a2eb1 SO	503	return -EFAULT;
53a0ac2e SO	504	}
53a0ac2e SO	505
e65b0f46 SO	506	remaining_len = len;
	507	msg_ptr = msg_data;
	508
	509	while (remaining_len > 0) {
	510
93d7e490	511	frag_len = min_t(size_t, sock->miu, remaining_len);
53a0ac2e	512
e65b0f46 SO	513	pr_debug("Fragment %zd bytes remaining %zd",
e65b0f46 SO	514	frag_len, remaining_len);
53a0ac2e	515
e65b0f46 SO	516	pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
	517	frag_len + LLCP_SEQUENCE_SIZE);
	518	if (pdu == NULL)
	519	return -ENOMEM;
	520
	521	skb_put(pdu, LLCP_SEQUENCE_SIZE);
	522
	523	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	524
bdbc59b3	525	skb_queue_tail(&sock->tx_queue, pdu);
e65b0f46 SO	526
	527	lock_sock(sk);
	528
	529	nfc_llcp_queue_i_frames(sock);
	530
	531	release_sock(sk);
	532
	533	remaining_len -= frag_len;
b4838d12	534	msg_ptr += frag_len;
e65b0f46	535	}
53a0ac2e	536
e65b0f46	537	kfree(msg_data);
53a0ac2e	538
43472fff	539	return len;
53a0ac2e	540	}
d094afa1 SO	541
	542	int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
	543	{
	544	struct sk_buff *skb;
	545	struct nfc_llcp_local *local;
	546
	547	pr_debug("Send rr nr %d\n", sock->recv_n);
	548
	549	local = sock->local;
	550	if (local == NULL)
	551	return -ENODEV;
	552
	553	skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
	554	if (skb == NULL)
	555	return -ENOMEM;
	556
	557	skb_put(skb, LLCP_SEQUENCE_SIZE);
	558
279cf174	559	skb->data[2] = sock->recv_n;
d094afa1 SO	560
	561	skb_queue_head(&local->tx_queue, skb);
	562
	563	return 0;
	564	}