[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;
}

struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdres_tlv(u8 tid, u8 sap)
{
	struct nfc_llcp_sdp_tlv *sdres;
	u8 value[2];

	sdres = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
	if (sdres == NULL)
		return NULL;

	value[0] = tid;
	value[1] = sap;

	sdres->tlv = nfc_llcp_build_tlv(LLCP_TLV_SDRES, value, 2,
					&sdres->tlv_len);
	if (sdres->tlv == NULL) {
		kfree(sdres);
		return NULL;
	}

	sdres->tid = tid;
	sdres->sap = sap;

	INIT_HLIST_NODE(&sdres->node);

	return sdres;
}

void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
{
	kfree(sdp->tlv);
	kfree(sdp);
}

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;
}

static struct sk_buff *nfc_llcp_allocate_snl(struct nfc_llcp_local *local,
					     size_t tlv_length)
{
	struct sk_buff *skb;
	struct nfc_dev *dev;
	u16 size = 0;

	if (local == NULL)
		return ERR_PTR(-ENODEV);

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

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

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

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

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

	return skb;
}

int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
			    struct hlist_head *tlv_list, size_t tlvs_len)
{
	struct nfc_llcp_sdp_tlv *sdp;
	struct hlist_node *n;
	struct sk_buff *skb;

	skb = nfc_llcp_allocate_snl(local, tlvs_len);
	if (IS_ERR(skb))
		return PTR_ERR(skb);

	hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
		memcpy(skb_put(skb, sdp->tlv_len), sdp->tlv, sdp->tlv_len);

		hlist_del(&sdp->node);

		nfc_llcp_free_sdp_tlv(sdp);
	}

	skb_queue_tail(&local->tx_queue, skb);

	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
e0ae7bac TE	120	struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdres_tlv(u8 tid, u8 sap)
	121	{
	122	struct nfc_llcp_sdp_tlv *sdres;
	123	u8 value[2];
	124
	125	sdres = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
	126	if (sdres == NULL)
	127	return NULL;
	128
	129	value[0] = tid;
	130	value[1] = sap;
	131
	132	sdres->tlv = nfc_llcp_build_tlv(LLCP_TLV_SDRES, value, 2,
	133	&sdres->tlv_len);
	134	if (sdres->tlv == NULL) {
	135	kfree(sdres);
	136	return NULL;
	137	}
	138
	139	sdres->tid = tid;
	140	sdres->sap = sap;
	141
	142	INIT_HLIST_NODE(&sdres->node);
	143
	144	return sdres;
	145	}
	146
	147	void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
	148	{
	149	kfree(sdp->tlv);
	150	kfree(sdp);
	151	}
	152
7a06e586 SO	153	int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
7a06e586 SO	154	u8 *tlv_array, u16 tlv_array_len)
d646960f SO	155	{
	156	u8 *tlv = tlv_array, type, length, offset = 0;
	157
	158	pr_debug("TLV array length %d\n", tlv_array_len);
	159
	160	if (local == NULL)
	161	return -ENODEV;
	162
	163	while (offset < tlv_array_len) {
	164	type = tlv[0];
	165	length = tlv[1];
	166
	167	pr_debug("type 0x%x length %d\n", type, length);
	168
	169	switch (type) {
	170	case LLCP_TLV_VERSION:
	171	local->remote_version = llcp_tlv_version(tlv);
	172	break;
	173	case LLCP_TLV_MIUX:
	174	local->remote_miu = llcp_tlv_miux(tlv) + 128;
	175	break;
	176	case LLCP_TLV_WKS:
	177	local->remote_wks = llcp_tlv_wks(tlv);
	178	break;
	179	case LLCP_TLV_LTO:
	180	local->remote_lto = llcp_tlv_lto(tlv) * 10;
	181	break;
	182	case LLCP_TLV_OPT:
	183	local->remote_opt = llcp_tlv_opt(tlv);
	184	break;
7a06e586 SO	185	default:
	186	pr_err("Invalid gt tlv value 0x%x\n", type);
	187	break;
	188	}
	189
	190	offset += length + 2;
	191	tlv += length + 2;
	192	}
	193
	194	pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
	195	local->remote_version, local->remote_miu,
	196	local->remote_lto, local->remote_opt,
	197	local->remote_wks);
	198
	199	return 0;
	200	}
	201
	202	int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
	203	u8 *tlv_array, u16 tlv_array_len)
	204	{
	205	u8 *tlv = tlv_array, type, length, offset = 0;
	206
	207	pr_debug("TLV array length %d\n", tlv_array_len);
	208
	209	if (sock == NULL)
	210	return -ENOTCONN;
	211
	212	while (offset < tlv_array_len) {
	213	type = tlv[0];
	214	length = tlv[1];
	215
	216	pr_debug("type 0x%x length %d\n", type, length);
	217
	218	switch (type) {
93d7e490	219	case LLCP_TLV_MIUX:
e4306bec	220	sock->remote_miu = llcp_tlv_miux(tlv) + 128;
93d7e490	221	break;
d646960f	222	case LLCP_TLV_RW:
e4306bec	223	sock->remote_rw = llcp_tlv_rw(tlv);
d646960f	224	break;
9dda50f4 SO	225	case LLCP_TLV_SN:
9dda50f4 SO	226	break;
d646960f SO	227	default:
	228	pr_err("Invalid gt tlv value 0x%x\n", type);
	229	break;
	230	}
	231
	232	offset += length + 2;
	233	tlv += length + 2;
	234	}
	235
e4306bec SO	236	pr_debug("sock %p rw %d miu %d\n", sock,
e4306bec SO	237	sock->remote_rw, sock->remote_miu);
d646960f SO	238
	239	return 0;
	240	}
	241
	242	static struct sk_buff llcp_add_header(struct sk_buff pdu,
427a2eb1	243	u8 dsap, u8 ssap, u8 ptype)
d646960f SO	244	{
	245	u8 header[2];
	246
	247	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
	248
	249	header[0] = (u8)((dsap << 2) \| (ptype >> 2));
	250	header[1] = (u8)((ptype << 6) \| ssap);
	251
	252	pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
	253
	254	memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
	255
	256	return pdu;
	257	}
	258
427a2eb1 SO	259	static struct sk_buff llcp_add_tlv(struct sk_buff pdu, u8 *tlv,
427a2eb1 SO	260	u8 tlv_length)
d646960f SO	261	{
	262	/* XXX Add an skb length check */
	263
	264	if (tlv == NULL)
	265	return NULL;
	266
	267	memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
	268
	269	return pdu;
	270	}
	271
	272	static struct sk_buff llcp_allocate_pdu(struct nfc_llcp_sock sock,
427a2eb1	273	u8 cmd, u16 size)
d646960f SO	274	{
	275	struct sk_buff *skb;
	276	int err;
	277
	278	if (sock->ssap == 0)
	279	return NULL;
	280
	281	skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
427a2eb1	282	size + LLCP_HEADER_SIZE, &err);
d646960f SO	283	if (skb == NULL) {
	284	pr_err("Could not allocate PDU\n");
	285	return NULL;
	286	}
	287
	288	skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
	289
	290	return skb;
	291	}
	292
	293	int nfc_llcp_disconnect(struct nfc_llcp_sock *sock)
	294	{
	295	struct sk_buff *skb;
	296	struct nfc_dev *dev;
	297	struct nfc_llcp_local *local;
d646960f SO	298
	299	pr_debug("Sending DISC\n");
	300
	301	local = sock->local;
	302	if (local == NULL)
	303	return -ENODEV;
	304
	305	dev = sock->dev;
	306	if (dev == NULL)
	307	return -ENODEV;
	308
92223906	309	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
d646960f SO	310	if (skb == NULL)
	311	return -ENOMEM;
	312
d646960f SO	313	skb_queue_tail(&local->tx_queue, skb);
	314
	315	return 0;
	316	}
	317
	318	int nfc_llcp_send_symm(struct nfc_dev *dev)
	319	{
	320	struct sk_buff *skb;
	321	struct nfc_llcp_local *local;
	322	u16 size = 0;
	323
	324	pr_debug("Sending SYMM\n");
	325
	326	local = nfc_llcp_find_local(dev);
	327	if (local == NULL)
	328	return -ENODEV;
	329
	330	size += LLCP_HEADER_SIZE;
	331	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	332
	333	skb = alloc_skb(size, GFP_KERNEL);
	334	if (skb == NULL)
	335	return -ENOMEM;
	336
	337	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	338
	339	skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
	340
2c2d45bd TE	341	__net_timestamp(skb);
2c2d45bd TE	342
4463523b TE	343	nfc_llcp_send_to_raw_sock(local, skb, NFC_LLCP_DIRECTION_TX);
4463523b TE	344
d646960f	345	return nfc_data_exchange(dev, local->target_idx, skb,
427a2eb1	346	nfc_llcp_recv, local);
d646960f SO	347	}
	348
	349	int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
	350	{
	351	struct nfc_llcp_local *local;
	352	struct sk_buff *skb;
	353	u8 *service_name_tlv = NULL, service_name_tlv_length;
eda21f16	354	u8 *miux_tlv = NULL, miux_tlv_length;
06d44f80	355	u8 *rw_tlv = NULL, rw_tlv_length, rw;
d646960f	356	int err;
06d44f80	357	u16 size = 0, miux;
d646960f SO	358
	359	pr_debug("Sending CONNECT\n");
	360
	361	local = sock->local;
	362	if (local == NULL)
	363	return -ENODEV;
	364
	365	if (sock->service_name != NULL) {
	366	service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
427a2eb1 SO	367	sock->service_name,
	368	sock->service_name_len,
	369	&service_name_tlv_length);
d646960f SO	370	size += service_name_tlv_length;
	371	}
	372
06d44f80 SO	373	/* If the socket parameters are not set, use the local ones */
	374	miux = sock->miux > LLCP_MAX_MIUX ? local->miux : sock->miux;
	375	rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
	376
	377	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1	378	&miux_tlv_length);
eda21f16 SO	379	size += miux_tlv_length;
eda21f16 SO	380
06d44f80	381	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
eda21f16 SO	382	size += rw_tlv_length;
eda21f16 SO	383
d646960f SO	384	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
	385
	386	skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
	387	if (skb == NULL) {
	388	err = -ENOMEM;
	389	goto error_tlv;
	390	}
	391
	392	if (service_name_tlv != NULL)
	393	skb = llcp_add_tlv(skb, service_name_tlv,
427a2eb1	394	service_name_tlv_length);
d646960f	395
eda21f16 SO	396	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	397	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
	398
d646960f SO	399	skb_queue_tail(&local->tx_queue, skb);
	400
	401	return 0;
	402
	403	error_tlv:
	404	pr_err("error %d\n", err);
	405
	406	kfree(service_name_tlv);
eda21f16 SO	407	kfree(miux_tlv);
eda21f16 SO	408	kfree(rw_tlv);
d646960f SO	409
	410	return err;
	411	}
	412
	413	int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
	414	{
	415	struct nfc_llcp_local *local;
	416	struct sk_buff *skb;
eda21f16	417	u8 *miux_tlv = NULL, miux_tlv_length;
06d44f80	418	u8 *rw_tlv = NULL, rw_tlv_length, rw;
eda21f16	419	int err;
06d44f80	420	u16 size = 0, miux;
d646960f SO	421
	422	pr_debug("Sending CC\n");
	423
	424	local = sock->local;
	425	if (local == NULL)
	426	return -ENODEV;
	427
06d44f80 SO	428	/* If the socket parameters are not set, use the local ones */
	429	miux = sock->miux > LLCP_MAX_MIUX ? local->miux : sock->miux;
	430	rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
	431
	432	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1	433	&miux_tlv_length);
eda21f16 SO	434	size += miux_tlv_length;
eda21f16 SO	435
06d44f80	436	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
eda21f16 SO	437	size += rw_tlv_length;
	438
	439	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
	440	if (skb == NULL) {
	441	err = -ENOMEM;
	442	goto error_tlv;
	443	}
	444
	445	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	446	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
d646960f SO	447
	448	skb_queue_tail(&local->tx_queue, skb);
	449
	450	return 0;
eda21f16 SO	451
	452	error_tlv:
	453	pr_err("error %d\n", err);
	454
	455	kfree(miux_tlv);
	456	kfree(rw_tlv);
	457
	458	return err;
d646960f SO	459	}
d646960f SO	460
e0ae7bac TE	461	static struct sk_buff nfc_llcp_allocate_snl(struct nfc_llcp_local local,
e0ae7bac TE	462	size_t tlv_length)
c43bb03d SO	463	{
	464	struct sk_buff *skb;
	465	struct nfc_dev *dev;
c43bb03d SO	466	u16 size = 0;
c43bb03d SO	467
c43bb03d	468	if (local == NULL)
e0ae7bac	469	return ERR_PTR(-ENODEV);
c43bb03d SO	470
	471	dev = local->dev;
	472	if (dev == NULL)
e0ae7bac	473	return ERR_PTR(-ENODEV);
c43bb03d SO	474
	475	size += LLCP_HEADER_SIZE;
	476	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
e0ae7bac	477	size += tlv_length;
c43bb03d SO	478
c43bb03d SO	479	skb = alloc_skb(size, GFP_KERNEL);
e0ae7bac TE	480	if (skb == NULL)
e0ae7bac TE	481	return ERR_PTR(-ENOMEM);
c43bb03d SO	482
	483	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	484
	485	skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
	486
e0ae7bac TE	487	return skb;
e0ae7bac TE	488	}
c43bb03d	489
e0ae7bac TE	490	int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
	491	struct hlist_head *tlv_list, size_t tlvs_len)
	492	{
	493	struct nfc_llcp_sdp_tlv *sdp;
	494	struct hlist_node *n;
	495	struct sk_buff *skb;
	496
	497	skb = nfc_llcp_allocate_snl(local, tlvs_len);
	498	if (IS_ERR(skb))
	499	return PTR_ERR(skb);
	500
	501	hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
	502	memcpy(skb_put(skb, sdp->tlv_len), sdp->tlv, sdp->tlv_len);
c43bb03d	503
e0ae7bac TE	504	hlist_del(&sdp->node);
	505
	506	nfc_llcp_free_sdp_tlv(sdp);
	507	}
	508
	509	skb_queue_tail(&local->tx_queue, skb);
c43bb03d SO	510
	511	return 0;
	512	}
	513
d646960f SO	514	int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
	515	{
	516	struct sk_buff *skb;
	517	struct nfc_dev *dev;
	518	u16 size = 1; /* Reason code */
	519
	520	pr_debug("Sending DM reason 0x%x\n", reason);
	521
	522	if (local == NULL)
	523	return -ENODEV;
	524
	525	dev = local->dev;
	526	if (dev == NULL)
	527	return -ENODEV;
	528
	529	size += LLCP_HEADER_SIZE;
	530	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	531
	532	skb = alloc_skb(size, GFP_KERNEL);
	533	if (skb == NULL)
	534	return -ENOMEM;
	535
	536	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	537
ffc29315	538	skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
d646960f SO	539
	540	memcpy(skb_put(skb, 1), &reason, 1);
	541
	542	skb_queue_head(&local->tx_queue, skb);
	543
	544	return 0;
	545	}
	546
	547	int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
	548	{
	549	struct sk_buff *skb;
	550	struct nfc_llcp_local *local;
	551
	552	pr_debug("Send DISC\n");
	553
	554	local = sock->local;
	555	if (local == NULL)
	556	return -ENODEV;
	557
	558	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
	559	if (skb == NULL)
	560	return -ENOMEM;
	561
	562	skb_queue_head(&local->tx_queue, skb);
	563
	564	return 0;
	565	}
53a0ac2e SO	566
53a0ac2e SO	567	int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
427a2eb1	568	struct msghdr *msg, size_t len)
53a0ac2e SO	569	{
53a0ac2e SO	570	struct sk_buff *pdu;
e65b0f46 SO	571	struct sock *sk = &sock->sk;
	572	struct nfc_llcp_local *local;
	573	size_t frag_len = 0, remaining_len;
	574	u8 msg_data, msg_ptr;
53a0ac2e	575
e65b0f46	576	pr_debug("Send I frame len %zd\n", len);
53a0ac2e	577
e65b0f46 SO	578	local = sock->local;
	579	if (local == NULL)
	580	return -ENODEV;
53a0ac2e	581
dd2bf43f SO	582	/* Remote is ready but has not acknowledged our frames */
dd2bf43f SO	583	if((sock->remote_ready &&
e4306bec SO	584	skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
e4306bec SO	585	skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
dd2bf43f SO	586	pr_err("Pending queue is full %d frames\n",
	587	skb_queue_len(&sock->tx_pending_queue));
	588	return -ENOBUFS;
	589	}
	590
	591	/* Remote is not ready and we've been queueing enough frames */
	592	if ((!sock->remote_ready &&
e4306bec	593	skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
dd2bf43f SO	594	pr_err("Tx queue is full %d frames\n",
	595	skb_queue_len(&sock->tx_queue));
	596	return -ENOBUFS;
	597	}
	598
e65b0f46 SO	599	msg_data = kzalloc(len, GFP_KERNEL);
	600	if (msg_data == NULL)
	601	return -ENOMEM;
53a0ac2e	602
e65b0f46	603	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
427a2eb1 SO	604	kfree(msg_data);
427a2eb1 SO	605	return -EFAULT;
53a0ac2e SO	606	}
53a0ac2e SO	607
e65b0f46 SO	608	remaining_len = len;
	609	msg_ptr = msg_data;
	610
	611	while (remaining_len > 0) {
	612
e4306bec	613	frag_len = min_t(size_t, sock->remote_miu, remaining_len);
53a0ac2e	614
e65b0f46 SO	615	pr_debug("Fragment %zd bytes remaining %zd",
e65b0f46 SO	616	frag_len, remaining_len);
53a0ac2e	617
e65b0f46 SO	618	pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
	619	frag_len + LLCP_SEQUENCE_SIZE);
	620	if (pdu == NULL)
	621	return -ENOMEM;
	622
	623	skb_put(pdu, LLCP_SEQUENCE_SIZE);
	624
	625	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	626
bdbc59b3	627	skb_queue_tail(&sock->tx_queue, pdu);
e65b0f46 SO	628
	629	lock_sock(sk);
	630
	631	nfc_llcp_queue_i_frames(sock);
	632
	633	release_sock(sk);
	634
	635	remaining_len -= frag_len;
b4838d12	636	msg_ptr += frag_len;
e65b0f46	637	}
53a0ac2e	638
e65b0f46	639	kfree(msg_data);
53a0ac2e	640
43472fff	641	return len;
53a0ac2e	642	}
d094afa1	643
94f418a2 SO	644	int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
	645	struct msghdr *msg, size_t len)
	646	{
	647	struct sk_buff *pdu;
	648	struct nfc_llcp_local *local;
	649	size_t frag_len = 0, remaining_len;
6e950fd2	650	u8 msg_ptr, msg_data;
94f418a2 SO	651	int err;
	652
	653	pr_debug("Send UI frame len %zd\n", len);
	654
	655	local = sock->local;
	656	if (local == NULL)
	657	return -ENODEV;
	658
6e950fd2 SO	659	msg_data = kzalloc(len, GFP_KERNEL);
	660	if (msg_data == NULL)
	661	return -ENOMEM;
	662
	663	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
	664	kfree(msg_data);
	665	return -EFAULT;
	666	}
	667
94f418a2	668	remaining_len = len;
6e950fd2	669	msg_ptr = msg_data;
94f418a2 SO	670
	671	while (remaining_len > 0) {
	672
e4306bec	673	frag_len = min_t(size_t, sock->remote_miu, remaining_len);
94f418a2 SO	674
	675	pr_debug("Fragment %zd bytes remaining %zd",
	676	frag_len, remaining_len);
	677
	678	pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
	679	frag_len + LLCP_HEADER_SIZE, &err);
	680	if (pdu == NULL) {
	681	pr_err("Could not allocate PDU\n");
	682	continue;
	683	}
	684
	685	pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
	686
	687	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	688
	689	/* No need to check for the peer RW for UI frames */
	690	skb_queue_tail(&local->tx_queue, pdu);
	691
	692	remaining_len -= frag_len;
	693	msg_ptr += frag_len;
	694	}
	695
6e950fd2 SO	696	kfree(msg_data);
6e950fd2 SO	697
94f418a2 SO	698	return len;
	699	}
	700
d094afa1 SO	701	int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
	702	{
	703	struct sk_buff *skb;
	704	struct nfc_llcp_local *local;
	705
	706	pr_debug("Send rr nr %d\n", sock->recv_n);
	707
	708	local = sock->local;
	709	if (local == NULL)
	710	return -ENODEV;
	711
	712	skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
	713	if (skb == NULL)
	714	return -ENOMEM;
	715
	716	skb_put(skb, LLCP_SEQUENCE_SIZE);
	717
279cf174	718	skb->data[2] = sock->recv_n;
d094afa1 SO	719
	720	skb_queue_head(&local->tx_queue, skb);
	721
	722	return 0;
	723	}