[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;
}

struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, char *uri,
						  size_t uri_len)
{
	struct nfc_llcp_sdp_tlv *sdreq;

	pr_debug("uri: %s, len: %zu\n", uri, uri_len);

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

	sdreq->tlv_len = uri_len + 3;

	if (uri[uri_len - 1] == 0)
		sdreq->tlv_len--;

	sdreq->tlv = kzalloc(sdreq->tlv_len + 1, GFP_KERNEL);
	if (sdreq->tlv == NULL) {
		kfree(sdreq);
		return NULL;
	}

	sdreq->tlv[0] = LLCP_TLV_SDREQ;
	sdreq->tlv[1] = sdreq->tlv_len - 2;
	sdreq->tlv[2] = tid;

	sdreq->tid = tid;
	sdreq->uri = sdreq->tlv + 3;
	memcpy(sdreq->uri, uri, uri_len);

	sdreq->time = jiffies;

	INIT_HLIST_NODE(&sdreq->node);

	return sdreq;
}

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

void nfc_llcp_free_sdp_tlv_list(struct hlist_head *head)
{
	struct nfc_llcp_sdp_tlv *sdp;
	struct hlist_node *n;

	hlist_for_each_entry_safe(sdp, n, head, node) {
		hlist_del(&sdp->node);

		nfc_llcp_free_sdp_tlv(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 = be16_to_cpu(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 = be16_to_cpu(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_snl_sdreq(struct nfc_llcp_local *local,
			    struct hlist_head *tlv_list, size_t tlvs_len)
{
	struct nfc_llcp_sdp_tlv *sdreq;
	struct hlist_node *n;
	struct sk_buff *skb;

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

	mutex_lock(&local->sdreq_lock);

	if (hlist_empty(&local->pending_sdreqs))
		mod_timer(&local->sdreq_timer,
			  jiffies + msecs_to_jiffies(3 * local->remote_lto));

	hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
		pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);

		memcpy(skb_put(skb, sdreq->tlv_len), sdreq->tlv,
		       sdreq->tlv_len);

		hlist_del(&sdreq->node);

		hlist_add_head(&sdreq->node, &local->pending_sdreqs);
	}

	mutex_unlock(&local->sdreq_lock);

	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
d9b8d8e1 TE	147	struct nfc_llcp_sdp_tlv nfc_llcp_build_sdreq_tlv(u8 tid, char uri,
	148	size_t uri_len)
	149	{
	150	struct nfc_llcp_sdp_tlv *sdreq;
	151
	152	pr_debug("uri: %s, len: %zu\n", uri, uri_len);
	153
	154	sdreq = kzalloc(sizeof(struct nfc_llcp_sdp_tlv), GFP_KERNEL);
	155	if (sdreq == NULL)
	156	return NULL;
	157
	158	sdreq->tlv_len = uri_len + 3;
	159
	160	if (uri[uri_len - 1] == 0)
	161	sdreq->tlv_len--;
	162
	163	sdreq->tlv = kzalloc(sdreq->tlv_len + 1, GFP_KERNEL);
	164	if (sdreq->tlv == NULL) {
	165	kfree(sdreq);
	166	return NULL;
	167	}
	168
	169	sdreq->tlv[0] = LLCP_TLV_SDREQ;
	170	sdreq->tlv[1] = sdreq->tlv_len - 2;
	171	sdreq->tlv[2] = tid;
	172
	173	sdreq->tid = tid;
	174	sdreq->uri = sdreq->tlv + 3;
	175	memcpy(sdreq->uri, uri, uri_len);
	176
40213fa8 TE	177	sdreq->time = jiffies;
40213fa8 TE	178
d9b8d8e1 TE	179	INIT_HLIST_NODE(&sdreq->node);
	180
	181	return sdreq;
	182	}
	183
e0ae7bac TE	184	void nfc_llcp_free_sdp_tlv(struct nfc_llcp_sdp_tlv *sdp)
	185	{
	186	kfree(sdp->tlv);
	187	kfree(sdp);
	188	}
	189
d9b8d8e1 TE	190	void nfc_llcp_free_sdp_tlv_list(struct hlist_head *head)
	191	{
	192	struct nfc_llcp_sdp_tlv *sdp;
	193	struct hlist_node *n;
	194
	195	hlist_for_each_entry_safe(sdp, n, head, node) {
	196	hlist_del(&sdp->node);
	197
	198	nfc_llcp_free_sdp_tlv(sdp);
	199	}
	200	}
	201
7a06e586 SO	202	int nfc_llcp_parse_gb_tlv(struct nfc_llcp_local *local,
7a06e586 SO	203	u8 *tlv_array, u16 tlv_array_len)
d646960f SO	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 (local == NULL)
	210	return -ENODEV;
	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) {
	219	case LLCP_TLV_VERSION:
	220	local->remote_version = llcp_tlv_version(tlv);
	221	break;
	222	case LLCP_TLV_MIUX:
	223	local->remote_miu = llcp_tlv_miux(tlv) + 128;
	224	break;
	225	case LLCP_TLV_WKS:
	226	local->remote_wks = llcp_tlv_wks(tlv);
	227	break;
	228	case LLCP_TLV_LTO:
	229	local->remote_lto = llcp_tlv_lto(tlv) * 10;
	230	break;
	231	case LLCP_TLV_OPT:
	232	local->remote_opt = llcp_tlv_opt(tlv);
	233	break;
7a06e586 SO	234	default:
	235	pr_err("Invalid gt tlv value 0x%x\n", type);
	236	break;
	237	}
	238
	239	offset += length + 2;
	240	tlv += length + 2;
	241	}
	242
	243	pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x\n",
	244	local->remote_version, local->remote_miu,
	245	local->remote_lto, local->remote_opt,
	246	local->remote_wks);
	247
	248	return 0;
	249	}
	250
	251	int nfc_llcp_parse_connection_tlv(struct nfc_llcp_sock *sock,
	252	u8 *tlv_array, u16 tlv_array_len)
	253	{
	254	u8 *tlv = tlv_array, type, length, offset = 0;
	255
	256	pr_debug("TLV array length %d\n", tlv_array_len);
	257
	258	if (sock == NULL)
	259	return -ENOTCONN;
	260
	261	while (offset < tlv_array_len) {
	262	type = tlv[0];
	263	length = tlv[1];
	264
	265	pr_debug("type 0x%x length %d\n", type, length);
	266
	267	switch (type) {
93d7e490	268	case LLCP_TLV_MIUX:
e4306bec	269	sock->remote_miu = llcp_tlv_miux(tlv) + 128;
93d7e490	270	break;
d646960f	271	case LLCP_TLV_RW:
e4306bec	272	sock->remote_rw = llcp_tlv_rw(tlv);
d646960f	273	break;
9dda50f4 SO	274	case LLCP_TLV_SN:
9dda50f4 SO	275	break;
d646960f SO	276	default:
	277	pr_err("Invalid gt tlv value 0x%x\n", type);
	278	break;
	279	}
	280
	281	offset += length + 2;
	282	tlv += length + 2;
	283	}
	284
e4306bec SO	285	pr_debug("sock %p rw %d miu %d\n", sock,
e4306bec SO	286	sock->remote_rw, sock->remote_miu);
d646960f SO	287
	288	return 0;
	289	}
	290
	291	static struct sk_buff llcp_add_header(struct sk_buff pdu,
427a2eb1	292	u8 dsap, u8 ssap, u8 ptype)
d646960f SO	293	{
	294	u8 header[2];
	295
	296	pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
	297
	298	header[0] = (u8)((dsap << 2) \| (ptype >> 2));
	299	header[1] = (u8)((ptype << 6) \| ssap);
	300
	301	pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
	302
	303	memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
	304
	305	return pdu;
	306	}
	307
427a2eb1 SO	308	static struct sk_buff llcp_add_tlv(struct sk_buff pdu, u8 *tlv,
427a2eb1 SO	309	u8 tlv_length)
d646960f SO	310	{
	311	/* XXX Add an skb length check */
	312
	313	if (tlv == NULL)
	314	return NULL;
	315
	316	memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
	317
	318	return pdu;
	319	}
	320
	321	static struct sk_buff llcp_allocate_pdu(struct nfc_llcp_sock sock,
427a2eb1	322	u8 cmd, u16 size)
d646960f SO	323	{
	324	struct sk_buff *skb;
	325	int err;
	326
	327	if (sock->ssap == 0)
	328	return NULL;
	329
	330	skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
427a2eb1	331	size + LLCP_HEADER_SIZE, &err);
d646960f SO	332	if (skb == NULL) {
	333	pr_err("Could not allocate PDU\n");
	334	return NULL;
	335	}
	336
	337	skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
	338
	339	return skb;
	340	}
	341
	342	int nfc_llcp_disconnect(struct nfc_llcp_sock *sock)
	343	{
	344	struct sk_buff *skb;
	345	struct nfc_dev *dev;
	346	struct nfc_llcp_local *local;
d646960f SO	347
	348	pr_debug("Sending DISC\n");
	349
	350	local = sock->local;
	351	if (local == NULL)
	352	return -ENODEV;
	353
	354	dev = sock->dev;
	355	if (dev == NULL)
	356	return -ENODEV;
	357
92223906	358	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
d646960f SO	359	if (skb == NULL)
	360	return -ENOMEM;
	361
d646960f SO	362	skb_queue_tail(&local->tx_queue, skb);
	363
	364	return 0;
	365	}
	366
	367	int nfc_llcp_send_symm(struct nfc_dev *dev)
	368	{
	369	struct sk_buff *skb;
	370	struct nfc_llcp_local *local;
	371	u16 size = 0;
	372
	373	pr_debug("Sending SYMM\n");
	374
	375	local = nfc_llcp_find_local(dev);
	376	if (local == NULL)
	377	return -ENODEV;
	378
	379	size += LLCP_HEADER_SIZE;
	380	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	381
	382	skb = alloc_skb(size, GFP_KERNEL);
	383	if (skb == NULL)
	384	return -ENOMEM;
	385
	386	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	387
	388	skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
	389
2c2d45bd TE	390	__net_timestamp(skb);
2c2d45bd TE	391
4463523b TE	392	nfc_llcp_send_to_raw_sock(local, skb, NFC_LLCP_DIRECTION_TX);
4463523b TE	393
d646960f	394	return nfc_data_exchange(dev, local->target_idx, skb,
427a2eb1	395	nfc_llcp_recv, local);
d646960f SO	396	}
	397
	398	int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
	399	{
	400	struct nfc_llcp_local *local;
	401	struct sk_buff *skb;
	402	u8 *service_name_tlv = NULL, service_name_tlv_length;
eda21f16	403	u8 *miux_tlv = NULL, miux_tlv_length;
06d44f80	404	u8 *rw_tlv = NULL, rw_tlv_length, rw;
d646960f	405	int err;
06d44f80	406	u16 size = 0, miux;
d646960f SO	407
	408	pr_debug("Sending CONNECT\n");
	409
	410	local = sock->local;
	411	if (local == NULL)
	412	return -ENODEV;
	413
	414	if (sock->service_name != NULL) {
	415	service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
427a2eb1 SO	416	sock->service_name,
	417	sock->service_name_len,
	418	&service_name_tlv_length);
d646960f SO	419	size += service_name_tlv_length;
	420	}
	421
06d44f80	422	/* If the socket parameters are not set, use the local ones */
5eef6669 SO	423	miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
5eef6669 SO	424	local->miux : sock->miux;
06d44f80 SO	425	rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
	426
	427	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1	428	&miux_tlv_length);
eda21f16 SO	429	size += miux_tlv_length;
eda21f16 SO	430
06d44f80	431	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
eda21f16 SO	432	size += rw_tlv_length;
eda21f16 SO	433
d646960f SO	434	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
	435
	436	skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
	437	if (skb == NULL) {
	438	err = -ENOMEM;
	439	goto error_tlv;
	440	}
	441
	442	if (service_name_tlv != NULL)
	443	skb = llcp_add_tlv(skb, service_name_tlv,
427a2eb1	444	service_name_tlv_length);
d646960f	445
eda21f16 SO	446	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	447	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
	448
d646960f SO	449	skb_queue_tail(&local->tx_queue, skb);
	450
	451	return 0;
	452
	453	error_tlv:
	454	pr_err("error %d\n", err);
	455
	456	kfree(service_name_tlv);
eda21f16 SO	457	kfree(miux_tlv);
eda21f16 SO	458	kfree(rw_tlv);
d646960f SO	459
	460	return err;
	461	}
	462
	463	int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
	464	{
	465	struct nfc_llcp_local *local;
	466	struct sk_buff *skb;
eda21f16	467	u8 *miux_tlv = NULL, miux_tlv_length;
06d44f80	468	u8 *rw_tlv = NULL, rw_tlv_length, rw;
eda21f16	469	int err;
06d44f80	470	u16 size = 0, miux;
d646960f SO	471
	472	pr_debug("Sending CC\n");
	473
	474	local = sock->local;
	475	if (local == NULL)
	476	return -ENODEV;
	477
06d44f80	478	/* If the socket parameters are not set, use the local ones */
5eef6669 SO	479	miux = be16_to_cpu(sock->miux) > LLCP_MAX_MIUX ?
5eef6669 SO	480	local->miux : sock->miux;
06d44f80 SO	481	rw = sock->rw > LLCP_MAX_RW ? local->rw : sock->rw;
	482
	483	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
427a2eb1	484	&miux_tlv_length);
eda21f16 SO	485	size += miux_tlv_length;
eda21f16 SO	486
06d44f80	487	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
eda21f16 SO	488	size += rw_tlv_length;
	489
	490	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
	491	if (skb == NULL) {
	492	err = -ENOMEM;
	493	goto error_tlv;
	494	}
	495
	496	skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
	497	skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
d646960f SO	498
	499	skb_queue_tail(&local->tx_queue, skb);
	500
	501	return 0;
eda21f16 SO	502
	503	error_tlv:
	504	pr_err("error %d\n", err);
	505
	506	kfree(miux_tlv);
	507	kfree(rw_tlv);
	508
	509	return err;
d646960f SO	510	}
d646960f SO	511
e0ae7bac TE	512	static struct sk_buff nfc_llcp_allocate_snl(struct nfc_llcp_local local,
e0ae7bac TE	513	size_t tlv_length)
c43bb03d SO	514	{
	515	struct sk_buff *skb;
	516	struct nfc_dev *dev;
c43bb03d SO	517	u16 size = 0;
c43bb03d SO	518
c43bb03d	519	if (local == NULL)
e0ae7bac	520	return ERR_PTR(-ENODEV);
c43bb03d SO	521
	522	dev = local->dev;
	523	if (dev == NULL)
e0ae7bac	524	return ERR_PTR(-ENODEV);
c43bb03d SO	525
	526	size += LLCP_HEADER_SIZE;
	527	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
e0ae7bac	528	size += tlv_length;
c43bb03d SO	529
c43bb03d SO	530	skb = alloc_skb(size, GFP_KERNEL);
e0ae7bac TE	531	if (skb == NULL)
e0ae7bac TE	532	return ERR_PTR(-ENOMEM);
c43bb03d SO	533
	534	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	535
	536	skb = llcp_add_header(skb, LLCP_SAP_SDP, LLCP_SAP_SDP, LLCP_PDU_SNL);
	537
e0ae7bac TE	538	return skb;
e0ae7bac TE	539	}
c43bb03d	540
e0ae7bac TE	541	int nfc_llcp_send_snl_sdres(struct nfc_llcp_local *local,
	542	struct hlist_head *tlv_list, size_t tlvs_len)
	543	{
	544	struct nfc_llcp_sdp_tlv *sdp;
	545	struct hlist_node *n;
	546	struct sk_buff *skb;
	547
	548	skb = nfc_llcp_allocate_snl(local, tlvs_len);
	549	if (IS_ERR(skb))
	550	return PTR_ERR(skb);
	551
	552	hlist_for_each_entry_safe(sdp, n, tlv_list, node) {
	553	memcpy(skb_put(skb, sdp->tlv_len), sdp->tlv, sdp->tlv_len);
c43bb03d	554
e0ae7bac TE	555	hlist_del(&sdp->node);
	556
	557	nfc_llcp_free_sdp_tlv(sdp);
	558	}
	559
	560	skb_queue_tail(&local->tx_queue, skb);
c43bb03d SO	561
	562	return 0;
	563	}
	564
d9b8d8e1 TE	565	int nfc_llcp_send_snl_sdreq(struct nfc_llcp_local *local,
	566	struct hlist_head *tlv_list, size_t tlvs_len)
	567	{
	568	struct nfc_llcp_sdp_tlv *sdreq;
	569	struct hlist_node *n;
	570	struct sk_buff *skb;
	571
	572	skb = nfc_llcp_allocate_snl(local, tlvs_len);
	573	if (IS_ERR(skb))
	574	return PTR_ERR(skb);
	575
	576	mutex_lock(&local->sdreq_lock);
	577
40213fa8 TE	578	if (hlist_empty(&local->pending_sdreqs))
	579	mod_timer(&local->sdreq_timer,
	580	jiffies + msecs_to_jiffies(3 * local->remote_lto));
	581
d9b8d8e1 TE	582	hlist_for_each_entry_safe(sdreq, n, tlv_list, node) {
	583	pr_debug("tid %d for %s\n", sdreq->tid, sdreq->uri);
	584
	585	memcpy(skb_put(skb, sdreq->tlv_len), sdreq->tlv,
	586	sdreq->tlv_len);
	587
	588	hlist_del(&sdreq->node);
	589
	590	hlist_add_head(&sdreq->node, &local->pending_sdreqs);
	591	}
	592
	593	mutex_unlock(&local->sdreq_lock);
	594
	595	skb_queue_tail(&local->tx_queue, skb);
	596
	597	return 0;
	598	}
	599
d646960f SO	600	int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
	601	{
	602	struct sk_buff *skb;
	603	struct nfc_dev *dev;
	604	u16 size = 1; /* Reason code */
	605
	606	pr_debug("Sending DM reason 0x%x\n", reason);
	607
	608	if (local == NULL)
	609	return -ENODEV;
	610
	611	dev = local->dev;
	612	if (dev == NULL)
	613	return -ENODEV;
	614
	615	size += LLCP_HEADER_SIZE;
	616	size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
	617
	618	skb = alloc_skb(size, GFP_KERNEL);
	619	if (skb == NULL)
	620	return -ENOMEM;
	621
	622	skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
	623
ffc29315	624	skb = llcp_add_header(skb, dsap, ssap, LLCP_PDU_DM);
d646960f SO	625
	626	memcpy(skb_put(skb, 1), &reason, 1);
	627
	628	skb_queue_head(&local->tx_queue, skb);
	629
	630	return 0;
	631	}
	632
	633	int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
	634	{
	635	struct sk_buff *skb;
	636	struct nfc_llcp_local *local;
	637
	638	pr_debug("Send DISC\n");
	639
	640	local = sock->local;
	641	if (local == NULL)
	642	return -ENODEV;
	643
	644	skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
	645	if (skb == NULL)
	646	return -ENOMEM;
	647
	648	skb_queue_head(&local->tx_queue, skb);
	649
	650	return 0;
	651	}
53a0ac2e SO	652
53a0ac2e SO	653	int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
427a2eb1	654	struct msghdr *msg, size_t len)
53a0ac2e SO	655	{
53a0ac2e SO	656	struct sk_buff *pdu;
e65b0f46 SO	657	struct sock *sk = &sock->sk;
	658	struct nfc_llcp_local *local;
	659	size_t frag_len = 0, remaining_len;
	660	u8 msg_data, msg_ptr;
53a0ac2e	661
e65b0f46	662	pr_debug("Send I frame len %zd\n", len);
53a0ac2e	663
e65b0f46 SO	664	local = sock->local;
	665	if (local == NULL)
	666	return -ENODEV;
53a0ac2e	667
dd2bf43f SO	668	/* Remote is ready but has not acknowledged our frames */
dd2bf43f SO	669	if((sock->remote_ready &&
e4306bec SO	670	skb_queue_len(&sock->tx_pending_queue) >= sock->remote_rw &&
e4306bec SO	671	skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
dd2bf43f SO	672	pr_err("Pending queue is full %d frames\n",
	673	skb_queue_len(&sock->tx_pending_queue));
	674	return -ENOBUFS;
	675	}
	676
	677	/* Remote is not ready and we've been queueing enough frames */
	678	if ((!sock->remote_ready &&
e4306bec	679	skb_queue_len(&sock->tx_queue) >= 2 * sock->remote_rw)) {
dd2bf43f SO	680	pr_err("Tx queue is full %d frames\n",
	681	skb_queue_len(&sock->tx_queue));
	682	return -ENOBUFS;
	683	}
	684
e65b0f46 SO	685	msg_data = kzalloc(len, GFP_KERNEL);
	686	if (msg_data == NULL)
	687	return -ENOMEM;
53a0ac2e	688
e65b0f46	689	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
427a2eb1 SO	690	kfree(msg_data);
427a2eb1 SO	691	return -EFAULT;
53a0ac2e SO	692	}
53a0ac2e SO	693
e65b0f46 SO	694	remaining_len = len;
	695	msg_ptr = msg_data;
	696
	697	while (remaining_len > 0) {
	698
e4306bec	699	frag_len = min_t(size_t, sock->remote_miu, remaining_len);
53a0ac2e	700
e65b0f46 SO	701	pr_debug("Fragment %zd bytes remaining %zd",
e65b0f46 SO	702	frag_len, remaining_len);
53a0ac2e	703
e65b0f46 SO	704	pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
	705	frag_len + LLCP_SEQUENCE_SIZE);
	706	if (pdu == NULL)
	707	return -ENOMEM;
	708
	709	skb_put(pdu, LLCP_SEQUENCE_SIZE);
	710
	711	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	712
bdbc59b3	713	skb_queue_tail(&sock->tx_queue, pdu);
e65b0f46 SO	714
	715	lock_sock(sk);
	716
	717	nfc_llcp_queue_i_frames(sock);
	718
	719	release_sock(sk);
	720
	721	remaining_len -= frag_len;
b4838d12	722	msg_ptr += frag_len;
e65b0f46	723	}
53a0ac2e	724
e65b0f46	725	kfree(msg_data);
53a0ac2e	726
43472fff	727	return len;
53a0ac2e	728	}
d094afa1	729
94f418a2 SO	730	int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
	731	struct msghdr *msg, size_t len)
	732	{
	733	struct sk_buff *pdu;
	734	struct nfc_llcp_local *local;
	735	size_t frag_len = 0, remaining_len;
6e950fd2	736	u8 msg_ptr, msg_data;
94f418a2 SO	737	int err;
	738
	739	pr_debug("Send UI frame len %zd\n", len);
	740
	741	local = sock->local;
	742	if (local == NULL)
	743	return -ENODEV;
	744
6e950fd2 SO	745	msg_data = kzalloc(len, GFP_KERNEL);
	746	if (msg_data == NULL)
	747	return -ENOMEM;
	748
	749	if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
	750	kfree(msg_data);
	751	return -EFAULT;
	752	}
	753
94f418a2	754	remaining_len = len;
6e950fd2	755	msg_ptr = msg_data;
94f418a2 SO	756
	757	while (remaining_len > 0) {
	758
e4306bec	759	frag_len = min_t(size_t, sock->remote_miu, remaining_len);
94f418a2 SO	760
	761	pr_debug("Fragment %zd bytes remaining %zd",
	762	frag_len, remaining_len);
	763
	764	pdu = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
	765	frag_len + LLCP_HEADER_SIZE, &err);
	766	if (pdu == NULL) {
	767	pr_err("Could not allocate PDU\n");
	768	continue;
	769	}
	770
	771	pdu = llcp_add_header(pdu, dsap, ssap, LLCP_PDU_UI);
	772
	773	memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
	774
	775	/* No need to check for the peer RW for UI frames */
	776	skb_queue_tail(&local->tx_queue, pdu);
	777
	778	remaining_len -= frag_len;
	779	msg_ptr += frag_len;
	780	}
	781
6e950fd2 SO	782	kfree(msg_data);
6e950fd2 SO	783
94f418a2 SO	784	return len;
	785	}
	786
d094afa1 SO	787	int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
	788	{
	789	struct sk_buff *skb;
	790	struct nfc_llcp_local *local;
	791
	792	pr_debug("Send rr nr %d\n", sock->recv_n);
	793
	794	local = sock->local;
	795	if (local == NULL)
	796	return -ENODEV;
	797
	798	skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
	799	if (skb == NULL)
	800	return -ENOMEM;
	801
	802	skb_put(skb, LLCP_SEQUENCE_SIZE);
	803
279cf174	804	skb->data[2] = sock->recv_n;
d094afa1 SO	805
	806	skb_queue_head(&local->tx_queue, skb);
	807
	808	return 0;
	809	}