[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->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;

	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;
	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_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
				      &miux_tlv_length);
	size += miux_tlv_length;

	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &local->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;
	int err;
	u16 size = 0;

	pr_debug("Sending CC\n");

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

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

	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &local->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->rw &&
	    skb_queue_len(&sock->tx_queue) >= 2 * sock->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->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->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->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 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;
d646960f SO	264
	265	pr_debug("Sending DISC\n");
	266
	267	local = sock->local;
	268	if (local == NULL)
	269	return -ENODEV;
	270
	271	dev = sock->dev;
	272	if (dev == NULL)
	273	return -ENODEV;
	274
92223906	275	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
d646960f SO	276	if (skb == NULL)
	277	return -ENOMEM;
	278
d646960f SO	279	skb_queue_tail(&local->tx_queue, skb);
	280
	281	return 0;
	282	}
	283
	284	int nfc_llcp_send_symm(struct nfc_dev *dev)
	285	{
	286	struct sk_buff *skb;
	287	struct nfc_llcp_local *local;
	288	u16 size = 0;
	289
	290	pr_debug("Sending SYMM\n");
	291
	292	local = nfc_llcp_find_local(dev);
	293	if (local == NULL)
	294	return -ENODEV;
	295
	296	size += LLCP_HEADER_SIZE;
	297	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	298
	299	skb = alloc_skb(size, GFP_KERNEL);
	300	if (skb == NULL)
	301	return -ENOMEM;
	302
	303	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	304
	305	skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
	306
2c2d45bd TE	307	__net_timestamp(skb);
2c2d45bd TE	308
4463523b TE	309	nfc_llcp_send_to_raw_sock(local, skb, NFC_LLCP_DIRECTION_TX);
4463523b TE	310
d646960f	311	return nfc_data_exchange(dev, local->target_idx, skb,
427a2eb1	312	nfc_llcp_recv, local);
d646960f SO	313	}
	314
	315	int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
	316	{
	317	struct nfc_llcp_local *local;
	318	struct sk_buff *skb;
	319	u8 *service_name_tlv = NULL, service_name_tlv_length;
eda21f16	320	u8 *miux_tlv = NULL, miux_tlv_length;
52feb444	321	u8 *rw_tlv = NULL, rw_tlv_length;
d646960f SO	322	int err;
	323	u16 size = 0;
	324
	325	pr_debug("Sending CONNECT\n");
	326
	327	local = sock->local;
	328	if (local == NULL)
	329	return -ENODEV;
	330
	331	if (sock->service_name != NULL) {
	332	service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
427a2eb1 SO	333	sock->service_name,
	334	sock->service_name_len,
	335	&service_name_tlv_length);
d646960f SO	336	size += service_name_tlv_length;
	337	}
	338
52feb444	339	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
427a2eb1	340	&miux_tlv_length);
eda21f16 SO	341	size += miux_tlv_length;
eda21f16 SO	342
52feb444	343	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &local->rw, 0, &rw_tlv_length);
eda21f16 SO	344	size += rw_tlv_length;
eda21f16 SO	345
d646960f SO	346	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
	347
	348	skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
	349	if (skb == NULL) {
	350	err = -ENOMEM;
	351	goto error_tlv;
	352	}
	353
	354	if (service_name_tlv != NULL)
	355	skb = llcp_add_tlv(skb, service_name_tlv,
427a2eb1	356	service_name_tlv_length);
d646960f	357
eda21f16 SO	358	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	359	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
	360
d646960f SO	361	skb_queue_tail(&local->tx_queue, skb);
	362
	363	return 0;
	364
	365	error_tlv:
	366	pr_err("error %d\n", err);
	367
	368	kfree(service_name_tlv);
eda21f16 SO	369	kfree(miux_tlv);
eda21f16 SO	370	kfree(rw_tlv);
d646960f SO	371
	372	return err;
	373	}
	374
	375	int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
	376	{
	377	struct nfc_llcp_local *local;
	378	struct sk_buff *skb;
eda21f16	379	u8 *miux_tlv = NULL, miux_tlv_length;
52feb444	380	u8 *rw_tlv = NULL, rw_tlv_length;
eda21f16 SO	381	int err;
eda21f16 SO	382	u16 size = 0;
d646960f SO	383
	384	pr_debug("Sending CC\n");
	385
	386	local = sock->local;
	387	if (local == NULL)
	388	return -ENODEV;
	389
52feb444	390	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
427a2eb1	391	&miux_tlv_length);
eda21f16 SO	392	size += miux_tlv_length;
eda21f16 SO	393
52feb444	394	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &local->rw, 0, &rw_tlv_length);
eda21f16 SO	395	size += rw_tlv_length;
	396
	397	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
	398	if (skb == NULL) {
	399	err = -ENOMEM;
	400	goto error_tlv;
	401	}
	402
	403	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	404	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
d646960f SO	405
	406	skb_queue_tail(&local->tx_queue, skb);
	407
	408	return 0;
eda21f16 SO	409
	410	error_tlv:
	411	pr_err("error %d\n", err);
	412
	413	kfree(miux_tlv);
	414	kfree(rw_tlv);
	415
	416	return err;
d646960f SO	417	}
d646960f SO	418
c43bb03d SO	419	int nfc_llcp_send_snl(struct nfc_llcp_local *local, u8 tid, u8 sap)
	420	{
	421	struct sk_buff *skb;
	422	struct nfc_dev *dev;
	423	u8 *sdres_tlv = NULL, sdres_tlv_length, sdres[2];
	424	u16 size = 0;
	425
	426	pr_debug("Sending SNL tid 0x%x sap 0x%x\n", tid, sap);
	427
	428	if (local == NULL)
	429	return -ENODEV;
	430
	431	dev = local->dev;
	432	if (dev == NULL)
	433	return -ENODEV;
	434
	435	sdres[0] = tid;
	436	sdres[1] = sap;
	437	sdres_tlv = nfc_llcp_build_tlv(LLCP_TLV_SDRES, sdres, 0,
	438	&sdres_tlv_length);
	439	if (sdres_tlv == NULL)
	440	return -ENOMEM;
	441
	442	size += LLCP_HEADER_SIZE;
	443	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	444	size += sdres_tlv_length;
	445
	446	skb = alloc_skb(size, GFP_KERNEL);
	447	if (skb == NULL) {
	448	kfree(sdres_tlv);
	449	return -ENOMEM;
	450	}
	451
	452	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	453
	454	skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
	455
	456	memcpy(skb_put(skb, sdres_tlv_length), sdres_tlv, sdres_tlv_length);
	457
	458	skb_queue_tail(&local->tx_queue, skb);
	459
	460	kfree(sdres_tlv);
	461
	462	return 0;
	463	}
	464
d646960f SO	465	int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
	466	{
	467	struct sk_buff *skb;
	468	struct nfc_dev *dev;
	469	u16 size = 1; /* Reason code */
	470
	471	pr_debug("Sending DM reason 0x%x\n", reason);
	472
	473	if (local == NULL)
	474	return -ENODEV;
	475
	476	dev = local->dev;
	477	if (dev == NULL)
	478	return -ENODEV;
	479
	480	size += LLCP_HEADER_SIZE;
	481	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	482
	483	skb = alloc_skb(size, GFP_KERNEL);
	484	if (skb == NULL)
	485	return -ENOMEM;
	486
	487	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	488
ffc29315	489	skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
d646960f SO	490
	491	memcpy(skb_put(skb, 1), &reason, 1);
	492
	493	skb_queue_head(&local->tx_queue, skb);
	494
	495	return 0;
	496	}
	497
	498	int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
	499	{
	500	struct sk_buff *skb;
	501	struct nfc_llcp_local *local;
	502
	503	pr_debug("Send DISC\n");
	504
	505	local = sock->local;
	506	if (local == NULL)
	507	return -ENODEV;
	508
	509	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
	510	if (skb == NULL)
	511	return -ENOMEM;
	512
	513	skb_queue_head(&local->tx_queue, skb);
	514
	515	return 0;
	516	}
53a0ac2e SO	517
53a0ac2e SO	518	int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
427a2eb1	519	struct msghdr *msg, size_t len)
53a0ac2e SO	520	{
53a0ac2e SO	521	struct sk_buff *pdu;
e65b0f46 SO	522	struct sock *sk = &sock->sk;
	523	struct nfc_llcp_local *local;
	524	size_t frag_len = 0, remaining_len;
	525	u8 msg_data, msg_ptr;
53a0ac2e	526
e65b0f46	527	pr_debug("Send I frame len %zd\n", len);
53a0ac2e	528
e65b0f46 SO	529	local = sock->local;
	530	if (local == NULL)
	531	return -ENODEV;
53a0ac2e	532
dd2bf43f SO	533	/* Remote is ready but has not acknowledged our frames */
	534	if((sock->remote_ready &&
	535	skb_queue_len(&sock->tx_pending_queue) >= sock->rw &&
	536	skb_queue_len(&sock->tx_queue) >= 2 * sock->rw)) {
	537	pr_err("Pending queue is full %d frames\n",
	538	skb_queue_len(&sock->tx_pending_queue));
	539	return -ENOBUFS;
	540	}
	541
	542	/* Remote is not ready and we've been queueing enough frames */
	543	if ((!sock->remote_ready &&
	544	skb_queue_len(&sock->tx_queue) >= 2 * sock->rw)) {
	545	pr_err("Tx queue is full %d frames\n",
	546	skb_queue_len(&sock->tx_queue));
	547	return -ENOBUFS;
	548	}
	549
e65b0f46 SO	550	msg_data = kzalloc(len, GFP_KERNEL);
	551	if (msg_data == NULL)
	552	return -ENOMEM;
53a0ac2e	553
e65b0f46	554	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
427a2eb1 SO	555	kfree(msg_data);
427a2eb1 SO	556	return -EFAULT;
53a0ac2e SO	557	}
53a0ac2e SO	558
e65b0f46 SO	559	remaining_len = len;
	560	msg_ptr = msg_data;
	561
	562	while (remaining_len > 0) {
	563
93d7e490	564	frag_len = min_t(size_t, sock->miu, remaining_len);
53a0ac2e	565
e65b0f46 SO	566	pr_debug("Fragment %zd bytes remaining %zd",
e65b0f46 SO	567	frag_len, remaining_len);
53a0ac2e	568
e65b0f46 SO	569	pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
	570	frag_len + LLCP_SEQUENCE_SIZE);
	571	if (pdu == NULL)
	572	return -ENOMEM;
	573
	574	skb_put(pdu, LLCP_SEQUENCE_SIZE);
	575
	576	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	577
bdbc59b3	578	skb_queue_tail(&sock->tx_queue, pdu);
e65b0f46 SO	579
	580	lock_sock(sk);
	581
	582	nfc_llcp_queue_i_frames(sock);
	583
	584	release_sock(sk);
	585
	586	remaining_len -= frag_len;
b4838d12	587	msg_ptr += frag_len;
e65b0f46	588	}
53a0ac2e	589
e65b0f46	590	kfree(msg_data);
53a0ac2e	591
43472fff	592	return len;
53a0ac2e	593	}
d094afa1	594
94f418a2 SO	595	int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
	596	struct msghdr *msg, size_t len)
	597	{
	598	struct sk_buff *pdu;
	599	struct nfc_llcp_local *local;
	600	size_t frag_len = 0, remaining_len;
6e950fd2	601	u8 msg_ptr, msg_data;
94f418a2 SO	602	int err;
	603
	604	pr_debug("Send UI frame len %zd\n", len);
	605
	606	local = sock->local;
	607	if (local == NULL)
	608	return -ENODEV;
	609
6e950fd2 SO	610	msg_data = kzalloc(len, GFP_KERNEL);
	611	if (msg_data == NULL)
	612	return -ENOMEM;
	613
	614	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
	615	kfree(msg_data);
	616	return -EFAULT;
	617	}
	618
94f418a2	619	remaining_len = len;
6e950fd2	620	msg_ptr = msg_data;
94f418a2 SO	621
	622	while (remaining_len > 0) {
	623
	624	frag_len = min_t(size_t, sock->miu, remaining_len);
	625
	626	pr_debug("Fragment %zd bytes remaining %zd",
	627	frag_len, remaining_len);
	628
	629	pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
	630	frag_len + LLCP_HEADER_SIZE, &err);
	631	if (pdu == NULL) {
	632	pr_err("Could not allocate PDU\n");
	633	continue;
	634	}
	635
	636	pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
	637
	638	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	639
	640	/* No need to check for the peer RW for UI frames */
	641	skb_queue_tail(&local->tx_queue, pdu);
	642
	643	remaining_len -= frag_len;
	644	msg_ptr += frag_len;
	645	}
	646
6e950fd2 SO	647	kfree(msg_data);
6e950fd2 SO	648
94f418a2 SO	649	return len;
	650	}
	651
d094afa1 SO	652	int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
	653	{
	654	struct sk_buff *skb;
	655	struct nfc_llcp_local *local;
	656
	657	pr_debug("Send rr nr %d\n", sock->recv_n);
	658
	659	local = sock->local;
	660	if (local == NULL)
	661	return -ENODEV;
	662
	663	skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
	664	if (skb == NULL)
	665	return -ENOMEM;
	666
	667	skb_put(skb, LLCP_SEQUENCE_SIZE);
	668
279cf174	669	skb->data[2] = sock->recv_n;
d094afa1 SO	670
	671	skb_queue_head(&local->tx_queue, skb);
	672
	673	return 0;
	674	}