Commit d646960f authored by Samuel Ortiz's avatar Samuel Ortiz Committed by John W. Linville
Browse files

NFC: Initial LLCP support



This patch is an initial implementation for the NFC Logical Link Control
protocol. It's also known as NFC peer to peer mode.
This is a basic implementation as it lacks SDP (services Discovery
Protocol), frames aggregation support, and frame rejecion parsing.
Follow up patches will implement those missing features.
This code has been tested against a Nexus S phone implementing LLCP 1.0.
Signed-off-by: default avatarSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 361f3cb7
......@@ -139,9 +139,22 @@ struct sockaddr_nfc {
__u32 nfc_protocol;
};
#define NFC_LLCP_MAX_SERVICE_NAME 63
struct sockaddr_nfc_llcp {
sa_family_t sa_family;
__u32 dev_idx;
__u32 target_idx;
__u32 nfc_protocol;
__u8 dsap; /* Destination SAP, if known */
__u8 ssap; /* Source SAP to be bound to */
char service_name[NFC_LLCP_MAX_SERVICE_NAME]; /* Service name URI */;
size_t service_name_len;
};
/* NFC socket protocols */
#define NFC_SOCKPROTO_RAW 0
#define NFC_SOCKPROTO_MAX 1
#define NFC_SOCKPROTO_LLCP 1
#define NFC_SOCKPROTO_MAX 2
#define NFC_HEADER_SIZE 1
......
......@@ -14,5 +14,6 @@ menuconfig NFC
be called nfc.
source "net/nfc/nci/Kconfig"
source "net/nfc/llcp/Kconfig"
source "drivers/nfc/Kconfig"
......@@ -6,3 +6,4 @@ obj-$(CONFIG_NFC) += nfc.o
obj-$(CONFIG_NFC_NCI) += nci/
nfc-objs := core.o netlink.o af_nfc.o rawsock.o
nfc-$(CONFIG_NFC_LLCP) += llcp/llcp.o llcp/commands.o llcp/sock.o
......@@ -240,6 +240,7 @@ int nfc_dep_link_down(struct nfc_dev *dev)
rc = dev->ops->dep_link_down(dev);
if (!rc) {
dev->dep_link_up = false;
nfc_llcp_mac_is_down(dev);
nfc_genl_dep_link_down_event(dev);
}
......@@ -254,6 +255,8 @@ int nfc_dep_link_is_up(struct nfc_dev *dev, u32 target_idx,
dev->dep_link_up = true;
dev->dep_rf_mode = rf_mode;
nfc_llcp_mac_is_up(dev, target_idx, comm_mode, rf_mode);
return nfc_genl_dep_link_up_event(dev, target_idx, comm_mode, rf_mode);
}
EXPORT_SYMBOL(nfc_dep_link_is_up);
......@@ -360,13 +363,13 @@ int nfc_set_remote_general_bytes(struct nfc_dev *dev, u8 *gb, u8 gb_len)
if (gb_len > NFC_MAX_GT_LEN)
return -EINVAL;
return 0;
return nfc_llcp_set_remote_gb(dev, gb, gb_len);
}
EXPORT_SYMBOL(nfc_set_remote_general_bytes);
u8 *nfc_get_local_general_bytes(struct nfc_dev *dev, u8 *gt_len)
{
return NULL;
return nfc_llcp_general_bytes(dev, gt_len);
}
EXPORT_SYMBOL(nfc_get_local_general_bytes);
......@@ -560,6 +563,10 @@ int nfc_register_device(struct nfc_dev *dev)
if (rc < 0)
return rc;
rc = nfc_llcp_register_device(dev);
if (rc)
pr_err("Could not register llcp device\n");
rc = nfc_genl_device_added(dev);
if (rc)
pr_debug("The userspace won't be notified that the device %s was added\n",
......@@ -591,6 +598,8 @@ void nfc_unregister_device(struct nfc_dev *dev)
mutex_unlock(&nfc_devlist_mutex);
nfc_llcp_unregister_device(dev);
rc = nfc_genl_device_removed(dev);
if (rc)
pr_debug("The userspace won't be notified that the device %s was removed\n",
......@@ -620,6 +629,10 @@ static int __init nfc_init(void)
if (rc)
goto err_rawsock;
rc = nfc_llcp_init();
if (rc)
goto err_llcp_sock;
rc = af_nfc_init();
if (rc)
goto err_af_nfc;
......@@ -627,6 +640,8 @@ static int __init nfc_init(void)
return 0;
err_af_nfc:
nfc_llcp_exit();
err_llcp_sock:
rawsock_exit();
err_rawsock:
nfc_genl_exit();
......@@ -638,6 +653,7 @@ err_genl:
static void __exit nfc_exit(void)
{
af_nfc_exit();
nfc_llcp_exit();
rawsock_exit();
nfc_genl_exit();
class_unregister(&nfc_class);
......
config NFC_LLCP
depends on NFC && EXPERIMENTAL
bool "NFC LLCP support (EXPERIMENTAL)"
default n
help
Say Y here if you want to build support for a kernel NFC LLCP
implementation.
\ No newline at end of file
/*
* Copyright (C) 2011 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/nfc.h>
#include <net/nfc/nfc.h>
#include "../nfc.h"
#include "llcp.h"
static u8 llcp_tlv_length[LLCP_TLV_MAX] = {
0,
1, /* VERSION */
2, /* MIUX */
2, /* WKS */
1, /* LTO */
1, /* RW */
0, /* SN */
1, /* OPT */
0, /* SDREQ */
2, /* SDRES */
};
static u8 llcp_tlv8(u8 *tlv, u8 type)
{
if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
return 0;
return tlv[2];
}
static u8 llcp_tlv16(u8 *tlv, u8 type)
{
if (tlv[0] != type || tlv[1] != llcp_tlv_length[tlv[0]])
return 0;
return be16_to_cpu(*((__be16 *)(tlv + 2)));
}
static u8 llcp_tlv_version(u8 *tlv)
{
return llcp_tlv8(tlv, LLCP_TLV_VERSION);
}
static u16 llcp_tlv_miux(u8 *tlv)
{
return llcp_tlv16(tlv, LLCP_TLV_MIUX) & 0x7f;
}
static u16 llcp_tlv_wks(u8 *tlv)
{
return llcp_tlv16(tlv, LLCP_TLV_WKS);
}
static u16 llcp_tlv_lto(u8 *tlv)
{
return llcp_tlv8(tlv, LLCP_TLV_LTO);
}
static u8 llcp_tlv_opt(u8 *tlv)
{
return llcp_tlv8(tlv, LLCP_TLV_OPT);
}
static u8 llcp_tlv_rw(u8 *tlv)
{
return llcp_tlv8(tlv, LLCP_TLV_RW) & 0xf;
}
u8 *nfc_llcp_build_tlv(u8 type, u8 *value, u8 value_length, u8 *tlv_length)
{
u8 *tlv, length;
pr_debug("type %d\n", type);
if (type >= LLCP_TLV_MAX)
return NULL;
length = llcp_tlv_length[type];
if (length == 0 && value_length == 0)
return NULL;
else
length = value_length;
*tlv_length = 2 + length;
tlv = kzalloc(2 + length, GFP_KERNEL);
if (tlv == NULL)
return tlv;
tlv[0] = type;
tlv[1] = length;
memcpy(tlv + 2, value, length);
return tlv;
}
int nfc_llcp_parse_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;
case LLCP_TLV_RW:
local->remote_rw = llcp_tlv_rw(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 rw %d\n",
local->remote_version, local->remote_miu,
local->remote_lto, local->remote_opt,
local->remote_wks, local->remote_rw);
return 0;
}
static struct sk_buff *llcp_add_header(struct sk_buff *pdu,
u8 dsap, u8 ssap, u8 ptype)
{
u8 header[2];
pr_debug("ptype 0x%x dsap 0x%x ssap 0x%x\n", ptype, dsap, ssap);
header[0] = (u8)((dsap << 2) | (ptype >> 2));
header[1] = (u8)((ptype << 6) | ssap);
pr_debug("header 0x%x 0x%x\n", header[0], header[1]);
memcpy(skb_put(pdu, LLCP_HEADER_SIZE), header, LLCP_HEADER_SIZE);
return pdu;
}
static struct sk_buff *llcp_add_tlv(struct sk_buff *pdu, u8 *tlv, u8 tlv_length)
{
/* XXX Add an skb length check */
if (tlv == NULL)
return NULL;
memcpy(skb_put(pdu, tlv_length), tlv, tlv_length);
return pdu;
}
static struct sk_buff *llcp_allocate_pdu(struct nfc_llcp_sock *sock,
u8 cmd, u16 size)
{
struct sk_buff *skb;
int err;
if (sock->ssap == 0)
return NULL;
skb = nfc_alloc_send_skb(sock->dev, &sock->sk, MSG_DONTWAIT,
size + LLCP_HEADER_SIZE, &err);
if (skb == NULL) {
pr_err("Could not allocate PDU\n");
return NULL;
}
skb = llcp_add_header(skb, sock->dsap, sock->ssap, cmd);
return skb;
}
int nfc_llcp_disconnect(struct nfc_llcp_sock *sock)
{
struct sk_buff *skb;
struct nfc_dev *dev;
struct nfc_llcp_local *local;
u16 size = 0;
pr_debug("Sending DISC\n");
local = sock->local;
if (local == NULL)
return -ENODEV;
dev = sock->dev;
if (dev == NULL)
return -ENODEV;
size += LLCP_HEADER_SIZE;
size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
skb = alloc_skb(size, GFP_ATOMIC);
if (skb == NULL)
return -ENOMEM;
skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
skb = llcp_add_header(skb, sock->ssap, sock->dsap, LLCP_PDU_DISC);
skb_queue_tail(&local->tx_queue, skb);
return 0;
}
int nfc_llcp_send_symm(struct nfc_dev *dev)
{
struct sk_buff *skb;
struct nfc_llcp_local *local;
u16 size = 0;
pr_debug("Sending SYMM\n");
local = nfc_llcp_find_local(dev);
if (local == NULL)
return -ENODEV;
size += LLCP_HEADER_SIZE;
size += dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
skb = alloc_skb(size, GFP_KERNEL);
if (skb == NULL)
return -ENOMEM;
skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
skb = llcp_add_header(skb, 0, 0, LLCP_PDU_SYMM);
return nfc_data_exchange(dev, local->target_idx, skb,
nfc_llcp_recv, local);
}
int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
{
struct nfc_llcp_local *local;
struct sk_buff *skb;
u8 *service_name_tlv = NULL, service_name_tlv_length;
int err;
u16 size = 0;
pr_debug("Sending CONNECT\n");
local = sock->local;
if (local == NULL)
return -ENODEV;
if (sock->service_name != NULL) {
service_name_tlv = nfc_llcp_build_tlv(LLCP_TLV_SN,
sock->service_name,
sock->service_name_len,
&service_name_tlv_length);
size += service_name_tlv_length;
}
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_queue_tail(&local->tx_queue, skb);
return 0;
error_tlv:
pr_err("error %d\n", err);
kfree(service_name_tlv);
return err;
}
int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
{
struct nfc_llcp_local *local;
struct sk_buff *skb;
pr_debug("Sending CC\n");
local = sock->local;
if (local == NULL)
return -ENODEV;
skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, 0);
if (skb == NULL)
return -ENOMEM;
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, 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;
}
This diff is collapsed.
/*
* 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.
*/
enum llcp_state {
LLCP_CONNECTED = 1, /* wait_for_packet() wants that */
LLCP_CLOSED,
LLCP_BOUND,
LLCP_LISTEN,
};
#define LLCP_DEFAULT_LTO 100
#define LLCP_DEFAULT_RW 1
#define LLCP_DEFAULT_MIU 128
#define LLCP_WKS_NUM_SAP 16
#define LLCP_SDP_NUM_SAP 16
#define LLCP_LOCAL_NUM_SAP 32
#define LLCP_LOCAL_SAP_OFFSET (LLCP_WKS_NUM_SAP + LLCP_SDP_NUM_SAP)
#define LLCP_MAX_SAP (LLCP_WKS_NUM_SAP + LLCP_SDP_NUM_SAP + LLCP_LOCAL_NUM_SAP)
struct nfc_llcp_sock;
struct nfc_llcp_local {
struct list_head list;
struct nfc_dev *dev;
struct mutex sdp_lock;
struct mutex socket_lock;
struct timer_list link_timer;
struct sk_buff_head tx_queue;
struct workqueue_struct *tx_wq;
struct work_struct tx_work;
struct workqueue_struct *rx_wq;
struct work_struct rx_work;
struct sk_buff *rx_pending;
struct workqueue_struct *timeout_wq;
struct work_struct timeout_work;
u32 target_idx;
u8 rf_mode;
u8 comm_mode;
unsigned long local_wks; /* Well known services */
unsigned long local_sdp; /* Local services */
unsigned long local_sap; /* Local SAPs, not available for discovery */
/* local */
u8 gb[NFC_MAX_GT_LEN];
u8 gb_len;
/* remote */
u8 remote_gb[NFC_MAX_GT_LEN];
u8 remote_gb_len;
u8 remote_version;
u16 remote_miu;
u16 remote_lto;
u8 remote_opt;
u16 remote_wks;
u8 remote_rw;
/* sockets array */
struct nfc_llcp_sock *sockets[LLCP_MAX_SAP];
};
struct nfc_llcp_sock {
struct sock sk;
struct list_head list;
struct nfc_dev *dev;
struct nfc_llcp_local *local;
u32 target_idx;
u32 nfc_protocol;
u8 ssap;
u8 dsap;
char *service_name;
size_t service_name_len;
/* Link variables */
u8 send_n;
u8 send_ack_n;
u8 recv_n;
u8 recv_ack_n;
/* Is the remote peer ready to receive */
u8 remote_ready;
struct sk_buff_head tx_queue;