NFC: add the NFC socket raw protocol

This socket protocol is used to perform data exchange with NFC
targets.

Signed-off-by: Lauro Ramos Venancio <lauro.venancio@openbossa.org>
Signed-off-by: Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Lauro Ramos Venancio 2011-07-01 19:31:36 -03:00 committed by John W. Linville
parent c7fe3b52c1
commit 23b7869c0f
5 changed files with 388 additions and 2 deletions

View File

@ -24,6 +24,9 @@
#ifndef __LINUX_NFC_H
#define __LINUX_NFC_H
#include <linux/types.h>
#include <linux/socket.h>
#define NFC_GENL_NAME "nfc"
#define NFC_GENL_VERSION 1
@ -109,7 +112,15 @@ enum nfc_attrs {
#define NFC_PROTO_ISO14443_MASK (1 << NFC_PROTO_ISO14443)
#define NFC_PROTO_NFC_DEP_MASK (1 << NFC_PROTO_NFC_DEP)
struct sockaddr_nfc {
sa_family_t sa_family;
__u32 dev_idx;
__u32 target_idx;
__u32 nfc_protocol;
};
/* NFC socket protocols */
#define NFC_SOCKPROTO_MAX 0
#define NFC_SOCKPROTO_RAW 0
#define NFC_SOCKPROTO_MAX 1
#endif /*__LINUX_NFC_H */

View File

@ -4,4 +4,4 @@
obj-$(CONFIG_NFC) += nfc.o
nfc-objs := core.o netlink.o af_nfc.o
nfc-objs := core.o netlink.o af_nfc.o rawsock.o

View File

@ -432,6 +432,10 @@ static int __init nfc_init(void)
/* the first generation must not be 0 */
nfc_devlist_generation = 1;
rc = rawsock_init();
if (rc)
goto err_rawsock;
rc = af_nfc_init();
if (rc)
goto err_af_nfc;
@ -439,6 +443,8 @@ static int __init nfc_init(void)
return 0;
err_af_nfc:
rawsock_exit();
err_rawsock:
nfc_genl_exit();
err_genl:
class_unregister(&nfc_class);
@ -448,6 +454,7 @@ static int __init nfc_init(void)
static void __exit nfc_exit(void)
{
af_nfc_exit();
rawsock_exit();
nfc_genl_exit();
class_unregister(&nfc_class);
}

View File

@ -42,6 +42,20 @@ struct nfc_protocol {
const struct nfc_protocol *nfc_proto);
};
struct nfc_rawsock {
struct sock sk;
struct nfc_dev *dev;
u32 target_idx;
struct work_struct tx_work;
bool tx_work_scheduled;
};
#define nfc_rawsock(sk) ((struct nfc_rawsock *) sk)
#define to_rawsock_sk(_tx_work) \
((struct sock *) container_of(_tx_work, struct nfc_rawsock, tx_work))
int __init rawsock_init(void);
void rawsock_exit(void);
int __init af_nfc_init(void);
void af_nfc_exit(void);
int nfc_proto_register(const struct nfc_protocol *nfc_proto);

354
net/nfc/rawsock.c Normal file
View File

@ -0,0 +1,354 @@
/*
* Copyright (C) 2011 Instituto Nokia de Tecnologia
*
* Authors:
* Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
* Lauro Ramos Venancio <lauro.venancio@openbossa.org>
*
* 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.
*/
#include <net/tcp_states.h>
#include <linux/nfc.h>
#include "nfc.h"
static void rawsock_write_queue_purge(struct sock *sk)
{
nfc_dbg("sk=%p", sk);
spin_lock_bh(&sk->sk_write_queue.lock);
__skb_queue_purge(&sk->sk_write_queue);
nfc_rawsock(sk)->tx_work_scheduled = false;
spin_unlock_bh(&sk->sk_write_queue.lock);
}
static void rawsock_report_error(struct sock *sk, int err)
{
nfc_dbg("sk=%p err=%d", sk, err);
sk->sk_shutdown = SHUTDOWN_MASK;
sk->sk_err = -err;
sk->sk_error_report(sk);
rawsock_write_queue_purge(sk);
}
static int rawsock_release(struct socket *sock)
{
struct sock *sk = sock->sk;
nfc_dbg("sock=%p", sock);
sock_orphan(sk);
sock_put(sk);
return 0;
}
static int rawsock_connect(struct socket *sock, struct sockaddr *_addr,
int len, int flags)
{
struct sock *sk = sock->sk;
struct sockaddr_nfc *addr = (struct sockaddr_nfc *)_addr;
struct nfc_dev *dev;
int rc = 0;
nfc_dbg("sock=%p sk=%p flags=%d", sock, sk, flags);
if (!addr || len < sizeof(struct sockaddr_nfc) ||
addr->sa_family != AF_NFC)
return -EINVAL;
nfc_dbg("addr dev_idx=%u target_idx=%u protocol=%u", addr->dev_idx,
addr->target_idx, addr->nfc_protocol);
lock_sock(sk);
if (sock->state == SS_CONNECTED) {
rc = -EISCONN;
goto error;
}
dev = nfc_get_device(addr->dev_idx);
if (!dev) {
rc = -ENODEV;
goto error;
}
if (addr->target_idx > dev->target_idx - 1 ||
addr->target_idx < dev->target_idx - dev->n_targets) {
rc = -EINVAL;
goto error;
}
if (addr->target_idx > dev->target_idx - 1 ||
addr->target_idx < dev->target_idx - dev->n_targets) {
rc = -EINVAL;
goto error;
}
rc = nfc_activate_target(dev, addr->target_idx, addr->nfc_protocol);
if (rc)
goto put_dev;
nfc_rawsock(sk)->dev = dev;
nfc_rawsock(sk)->target_idx = addr->target_idx;
sock->state = SS_CONNECTED;
sk->sk_state = TCP_ESTABLISHED;
sk->sk_state_change(sk);
release_sock(sk);
return 0;
put_dev:
nfc_put_device(dev);
error:
release_sock(sk);
return rc;
}
static int rawsock_add_header(struct sk_buff *skb)
{
if (skb_cow_head(skb, 1))
return -ENOMEM;
*skb_push(skb, 1) = 0;
return 0;
}
static void rawsock_data_exchange_complete(void *context, struct sk_buff *skb,
int err)
{
struct sock *sk = (struct sock *) context;
BUG_ON(in_irq());
nfc_dbg("sk=%p err=%d", sk, err);
if (err)
goto error;
err = rawsock_add_header(skb);
if (err)
goto error;
err = sock_queue_rcv_skb(sk, skb);
if (err)
goto error;
spin_lock_bh(&sk->sk_write_queue.lock);
if (!skb_queue_empty(&sk->sk_write_queue))
schedule_work(&nfc_rawsock(sk)->tx_work);
else
nfc_rawsock(sk)->tx_work_scheduled = false;
spin_unlock_bh(&sk->sk_write_queue.lock);
sock_put(sk);
return;
error:
rawsock_report_error(sk, err);
sock_put(sk);
}
static void rawsock_tx_work(struct work_struct *work)
{
struct sock *sk = to_rawsock_sk(work);
struct nfc_dev *dev = nfc_rawsock(sk)->dev;
u32 target_idx = nfc_rawsock(sk)->target_idx;
struct sk_buff *skb;
int rc;
nfc_dbg("sk=%p target_idx=%u", sk, target_idx);
if (sk->sk_shutdown & SEND_SHUTDOWN) {
rawsock_write_queue_purge(sk);
return;
}
skb = skb_dequeue(&sk->sk_write_queue);
sock_hold(sk);
rc = nfc_data_exchange(dev, target_idx, skb,
rawsock_data_exchange_complete, sk);
if (rc) {
rawsock_report_error(sk, rc);
sock_put(sk);
}
}
static int rawsock_sendmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t len)
{
struct sock *sk = sock->sk;
struct sk_buff *skb;
int rc;
nfc_dbg("sock=%p sk=%p len=%zu", sock, sk, len);
if (msg->msg_namelen)
return -EOPNOTSUPP;
if (sock->state != SS_CONNECTED)
return -ENOTCONN;
skb = sock_alloc_send_skb(sk, len, msg->msg_flags & MSG_DONTWAIT,
&rc);
if (!skb)
return rc;
rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
if (rc < 0) {
kfree_skb(skb);
return rc;
}
spin_lock_bh(&sk->sk_write_queue.lock);
__skb_queue_tail(&sk->sk_write_queue, skb);
if (!nfc_rawsock(sk)->tx_work_scheduled) {
schedule_work(&nfc_rawsock(sk)->tx_work);
nfc_rawsock(sk)->tx_work_scheduled = true;
}
spin_unlock_bh(&sk->sk_write_queue.lock);
return len;
}
static int rawsock_recvmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t len, int flags)
{
int noblock = flags & MSG_DONTWAIT;
struct sock *sk = sock->sk;
struct sk_buff *skb;
int copied;
int rc;
nfc_dbg("sock=%p sk=%p len=%zu flags=%d", sock, sk, len, flags);
skb = skb_recv_datagram(sk, flags, noblock, &rc);
if (!skb)
return rc;
msg->msg_namelen = 0;
copied = skb->len;
if (len < copied) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
rc = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
skb_free_datagram(sk, skb);
return rc ? : copied;
}
static const struct proto_ops rawsock_ops = {
.family = PF_NFC,
.owner = THIS_MODULE,
.release = rawsock_release,
.bind = sock_no_bind,
.connect = rawsock_connect,
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.getname = sock_no_getname,
.poll = datagram_poll,
.ioctl = sock_no_ioctl,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
.setsockopt = sock_no_setsockopt,
.getsockopt = sock_no_getsockopt,
.sendmsg = rawsock_sendmsg,
.recvmsg = rawsock_recvmsg,
.mmap = sock_no_mmap,
};
static void rawsock_destruct(struct sock *sk)
{
nfc_dbg("sk=%p", sk);
if (sk->sk_state == TCP_ESTABLISHED) {
nfc_deactivate_target(nfc_rawsock(sk)->dev,
nfc_rawsock(sk)->target_idx);
nfc_put_device(nfc_rawsock(sk)->dev);
}
skb_queue_purge(&sk->sk_receive_queue);
if (!sock_flag(sk, SOCK_DEAD)) {
nfc_err("Freeing alive NFC raw socket %p", sk);
return;
}
}
static int rawsock_create(struct net *net, struct socket *sock,
const struct nfc_protocol *nfc_proto)
{
struct sock *sk;
nfc_dbg("sock=%p", sock);
if (sock->type != SOCK_SEQPACKET)
return -ESOCKTNOSUPPORT;
sock->ops = &rawsock_ops;
sk = sk_alloc(net, PF_NFC, GFP_KERNEL, nfc_proto->proto);
if (!sk)
return -ENOMEM;
sock_init_data(sock, sk);
sk->sk_protocol = nfc_proto->id;
sk->sk_destruct = rawsock_destruct;
sock->state = SS_UNCONNECTED;
INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work);
nfc_rawsock(sk)->tx_work_scheduled = false;
return 0;
}
static struct proto rawsock_proto = {
.name = "NFC_RAW",
.owner = THIS_MODULE,
.obj_size = sizeof(struct nfc_rawsock),
};
static const struct nfc_protocol rawsock_nfc_proto = {
.id = NFC_SOCKPROTO_RAW,
.proto = &rawsock_proto,
.owner = THIS_MODULE,
.create = rawsock_create
};
int __init rawsock_init(void)
{
int rc;
rc = nfc_proto_register(&rawsock_nfc_proto);
return rc;
}
void rawsock_exit(void)
{
nfc_proto_unregister(&rawsock_nfc_proto);
}