531 lines
11 KiB
C
531 lines
11 KiB
C
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/*
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* Copyright (C) 2011 Intel Corporation. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the
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* Free Software Foundation, Inc.,
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* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/nfc.h>
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#include <net/nfc/nfc.h>
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#include "../nfc.h"
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#include "llcp.h"
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static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
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0,
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1, /* VERSION */
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2, /* MIUX */
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2, /* WKS */
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1, /* LTO */
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1, /* RW */
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0, /* SN */
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1, /* OPT */
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0, /* SDREQ */
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2, /* SDRES */
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};
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static u8 llcp_tlv8(u8 *tlv, u8 type)
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{
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if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
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return 0;
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return tlv[2];
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}
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static u8 llcp_tlv16(u8 *tlv, u8 type)
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{
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if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
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return 0;
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return be16_to_cpu(*((__be16 *)(tlv + 2)));
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}
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static u8 llcp_tlv_version(u8 *tlv)
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{
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return llcp_tlv8(tlv, LLCP_TLV_VERSION);
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}
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static u16 llcp_tlv_miux(u8 *tlv)
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{
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return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7f;
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}
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static u16 llcp_tlv_wks(u8 *tlv)
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{
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return llcp_tlv16(tlv, LLCP_TLV_WKS);
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}
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static u16 llcp_tlv_lto(u8 *tlv)
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{
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return llcp_tlv8(tlv, LLCP_TLV_LTO);
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}
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static u8 llcp_tlv_opt(u8 *tlv)
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{
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return llcp_tlv8(tlv, LLCP_TLV_OPT);
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}
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static u8 llcp_tlv_rw(u8 *tlv)
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{
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return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
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}
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u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length)
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{
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u8 *tlv, length;
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pr_debug("type %d\n", type);
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if (type >= LLCP_TLV_MAX)
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return NULL;
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length = llcp_tlv_length[type];
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if (length == 0 && value_length == 0)
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return NULL;
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else
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length = value_length;
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*tlv_length = 2 + length;
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tlv = kzalloc(2 + length, GFP_KERNEL);
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if (tlv == NULL)
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return tlv;
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tlv[0] = type;
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tlv[1] = length;
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memcpy(tlv + 2, value, length);
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return tlv;
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}
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int nfc_llcp_parse_tlv(struct nfc_llcp_local *local,
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u8 *tlv_array, u16 tlv_array_len)
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{
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u8 *tlv = tlv_array, type, length, offset = 0;
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pr_debug("TLV array length %d\n", tlv_array_len);
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if (local == NULL)
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return -ENODEV;
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while (offset < tlv_array_len) {
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type = tlv[0];
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length = tlv[1];
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pr_debug("type 0x%x length %d\n", type, length);
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switch (type) {
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case LLCP_TLV_VERSION:
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local->remote_version = llcp_tlv_version(tlv);
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break;
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case LLCP_TLV_MIUX:
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local->remote_miu = llcp_tlv_miux(tlv) + 128;
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break;
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case LLCP_TLV_WKS:
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local->remote_wks = llcp_tlv_wks(tlv);
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break;
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case LLCP_TLV_LTO:
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local->remote_lto = llcp_tlv_lto(tlv) * 10;
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break;
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case LLCP_TLV_OPT:
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local->remote_opt = llcp_tlv_opt(tlv);
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break;
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case LLCP_TLV_RW:
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local->remote_rw = llcp_tlv_rw(tlv);
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break;
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case LLCP_TLV_SN:
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break;
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default:
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pr_err("Invalid gt tlv value 0x%x\n", type);
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break;
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}
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offset += length + 2;
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tlv += length + 2;
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}
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pr_debug("version 0x%x miu %d lto %d opt 0x%x wks 0x%x rw %d\n",
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local->remote_version, local->remote_miu,
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local->remote_lto, local->remote_opt,
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local->remote_wks, local->remote_rw);
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return 0;
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}
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static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
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u8 dsap, u8 ssap, u8 ptype)
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{
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u8 header[2];
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pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
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header[0] = (u8)((dsap << 2) | (ptype >> 2));
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header[1] = (u8)((ptype << 6) | ssap);
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pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
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memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
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return pdu;
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}
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static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv,
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u8 tlv_length)
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{
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/* XXX Add an skb length check */
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if (tlv == NULL)
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return NULL;
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memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
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return pdu;
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}
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static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
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u8 cmd, u16 size)
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{
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struct sk_buff *skb;
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int err;
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if (sock->ssap == 0)
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return NULL;
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skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
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size + LLCP_HEADER_SIZE, &err);
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if (skb == NULL) {
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pr_err("Could not allocate PDU\n");
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return NULL;
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}
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skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
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return skb;
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}
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int nfc_llcp_disconnect(struct nfc_llcp_sock *sock)
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{
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struct sk_buff *skb;
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struct nfc_dev *dev;
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struct nfc_llcp_local *local;
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u16 size = 0;
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pr_debug("Sending DISC\n");
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local = sock->local;
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if (local == NULL)
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return -ENODEV;
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dev = sock->dev;
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if (dev == NULL)
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return -ENODEV;
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size += LLCP_HEADER_SIZE;
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size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
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skb = alloc_skb(size, GFP_ATOMIC);
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if (skb == NULL)
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return -ENOMEM;
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skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
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skb = llcp_add_header(skb, sock->ssap, sock->dsap, LLCP_PDU_DISC);
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skb_queue_tail(&local->tx_queue, skb);
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return 0;
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}
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int nfc_llcp_send_symm(struct nfc_dev *dev)
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{
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struct sk_buff *skb;
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struct nfc_llcp_local *local;
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u16 size = 0;
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pr_debug("Sending SYMM\n");
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local = nfc_llcp_find_local(dev);
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if (local == NULL)
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return -ENODEV;
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size += LLCP_HEADER_SIZE;
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size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
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skb = alloc_skb(size, GFP_KERNEL);
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if (skb == NULL)
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return -ENOMEM;
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skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
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skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
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return nfc_data_exchange(dev, local->target_idx, skb,
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nfc_llcp_recv, local);
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}
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int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
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{
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struct nfc_llcp_local *local;
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struct sk_buff *skb;
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u8 *service_name_tlv = NULL, service_name_tlv_length;
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u8 *miux_tlv = NULL, miux_tlv_length;
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u8 *rw_tlv = NULL, rw_tlv_length, rw;
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__be16 miux;
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int err;
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u16 size = 0;
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pr_debug("Sending CONNECT\n");
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local = sock->local;
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if (local == NULL)
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return -ENODEV;
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|
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if (sock->service_name != NULL) {
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service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
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sock->service_name,
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sock->service_name_len,
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|
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&service_name_tlv_length);
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|
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size += service_name_tlv_length;
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|
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}
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|
|
|
||
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miux = cpu_to_be16(LLCP_MAX_MIUX);
|
||
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miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
|
||
|
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&miux_tlv_length);
|
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size += miux_tlv_length;
|
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|
|
|
||
|
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rw = LLCP_MAX_RW;
|
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|
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rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
|
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|
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size += rw_tlv_length;
|
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|
|
|
||
|
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pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
|
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|
|
|
||
|
|
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);
|
||
|
|
|
||
|
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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);
|
||
|
|
|
||
|
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kfree(service_name_tlv);
|
||
|
|
kfree(miux_tlv);
|
||
|
|
kfree(rw_tlv);
|
||
|
|
|
||
|
|
return err;
|
||
|
|
}
|
||
|
|
|
||
|
|
int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
|
||
|
|
{
|
||
|
|
struct nfc_llcp_local *local;
|
||
|
|
struct sk_buff *skb;
|
||
|
|
u8 *miux_tlv = NULL, miux_tlv_length;
|
||
|
|
u8 *rw_tlv = NULL, rw_tlv_length, rw;
|
||
|
|
__be16 miux;
|
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|
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int err;
|
||
|
|
u16 size = 0;
|
||
|
|
|
||
|
|
pr_debug("Sending CC\n");
|
||
|
|
|
||
|
|
local = sock->local;
|
||
|
|
if (local == NULL)
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
miux = cpu_to_be16(LLCP_MAX_MIUX);
|
||
|
|
miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
|
||
|
|
&miux_tlv_length);
|
||
|
|
size += miux_tlv_length;
|
||
|
|
|
||
|
|
rw = LLCP_MAX_RW;
|
||
|
|
rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
|
||
|
|
size += rw_tlv_length;
|
||
|
|
|
||
|
|
skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
|
||
|
|
if (skb == NULL) {
|
||
|
|
err = -ENOMEM;
|
||
|
|
goto error_tlv;
|
||
|
|
}
|
||
|
|
|
||
|
|
skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
|
||
|
|
skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
|
||
|
|
|
||
|
|
skb_queue_tail(&local->tx_queue, skb);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
error_tlv:
|
||
|
|
pr_err("error %d\n", err);
|
||
|
|
|
||
|
|
kfree(miux_tlv);
|
||
|
|
kfree(rw_tlv);
|
||
|
|
|
||
|
|
return err;
|
||
|
|
}
|
||
|
|
|
||
|
|
int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
|
||
|
|
{
|
||
|
|
struct sk_buff *skb;
|
||
|
|
struct nfc_dev *dev;
|
||
|
|
u16 size = 1; /* Reason code */
|
||
|
|
|
||
|
|
pr_debug("Sending DM reason 0x%x\n", reason);
|
||
|
|
|
||
|
|
if (local == NULL)
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
dev = local->dev;
|
||
|
|
if (dev == NULL)
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
size += LLCP_HEADER_SIZE;
|
||
|
|
size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
|
||
|
|
|
||
|
|
skb = alloc_skb(size, GFP_KERNEL);
|
||
|
|
if (skb == NULL)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
|
||
|
|
|
||
|
|
skb = llcp_add_header(skb, ssap, dsap, LLCP_PDU_DM);
|
||
|
|
|
||
|
|
memcpy(skb_put(skb, 1), &reason, 1);
|
||
|
|
|
||
|
|
skb_queue_head(&local->tx_queue, skb);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
int nfc_llcp_send_disconnect(struct nfc_llcp_sock *sock)
|
||
|
|
{
|
||
|
|
struct sk_buff *skb;
|
||
|
|
struct nfc_llcp_local *local;
|
||
|
|
|
||
|
|
pr_debug("Send DISC\n");
|
||
|
|
|
||
|
|
local = sock->local;
|
||
|
|
if (local == NULL)
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
skb = llcp_allocate_pdu(sock, LLCP_PDU_DISC, 0);
|
||
|
|
if (skb == NULL)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
skb_queue_head(&local->tx_queue, skb);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
|
||
|
|
struct msghdr *msg, size_t len)
|
||
|
|
{
|
||
|
|
struct sk_buff *pdu;
|
||
|
|
struct sock *sk = &sock->sk;
|
||
|
|
struct nfc_llcp_local *local;
|
||
|
|
size_t frag_len = 0, remaining_len;
|
||
|
|
u8 *msg_data, *msg_ptr;
|
||
|
|
|
||
|
|
pr_debug("Send I frame len %zd\n", len);
|
||
|
|
|
||
|
|
local = sock->local;
|
||
|
|
if (local == NULL)
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
msg_data = kzalloc(len, GFP_KERNEL);
|
||
|
|
if (msg_data == NULL)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
if (memcpy_fromiovec(msg_data, msg->msg_iov, len)) {
|
||
|
|
kfree(msg_data);
|
||
|
|
return -EFAULT;
|
||
|
|
}
|
||
|
|
|
||
|
|
remaining_len = len;
|
||
|
|
msg_ptr = msg_data;
|
||
|
|
|
||
|
|
while (remaining_len > 0) {
|
||
|
|
|
||
|
|
frag_len = min_t(size_t, local->remote_miu, remaining_len);
|
||
|
|
|
||
|
|
pr_debug("Fragment %zd bytes remaining %zd",
|
||
|
|
frag_len, remaining_len);
|
||
|
|
|
||
|
|
pdu = llcp_allocate_pdu(sock, LLCP_PDU_I,
|
||
|
|
frag_len + LLCP_SEQUENCE_SIZE);
|
||
|
|
if (pdu == NULL)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
skb_put(pdu, LLCP_SEQUENCE_SIZE);
|
||
|
|
|
||
|
|
memcpy(skb_put(pdu, frag_len), msg_ptr, frag_len);
|
||
|
|
|
||
|
|
skb_queue_head(&sock->tx_queue, pdu);
|
||
|
|
|
||
|
|
lock_sock(sk);
|
||
|
|
|
||
|
|
nfc_llcp_queue_i_frames(sock);
|
||
|
|
|
||
|
|
release_sock(sk);
|
||
|
|
|
||
|
|
remaining_len -= frag_len;
|
||
|
|
msg_ptr += frag_len;
|
||
|
|
}
|
||
|
|
|
||
|
|
kfree(msg_data);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
int nfc_llcp_send_rr(struct nfc_llcp_sock *sock)
|
||
|
|
{
|
||
|
|
struct sk_buff *skb;
|
||
|
|
struct nfc_llcp_local *local;
|
||
|
|
|
||
|
|
pr_debug("Send rr nr %d\n", sock->recv_n);
|
||
|
|
|
||
|
|
local = sock->local;
|
||
|
|
if (local == NULL)
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
skb = llcp_allocate_pdu(sock, LLCP_PDU_RR, LLCP_SEQUENCE_SIZE);
|
||
|
|
if (skb == NULL)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
skb_put(skb, LLCP_SEQUENCE_SIZE);
|
||
|
|
|
||
|
|
skb->data[2] = sock->recv_n % 16;
|
||
|
|
|
||
|
|
skb_queue_head(&local->tx_queue, skb);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|