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>
diff --git a/include/linux/nfc.h b/include/linux/nfc.h
index 15f8cb3..330a4c5 100644
--- a/include/linux/nfc.h
+++ b/include/linux/nfc.h
@@ -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 @@
#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 */
diff --git a/net/nfc/Makefile b/net/nfc/Makefile
index e081fdb..16250c3 100644
--- a/net/nfc/Makefile
+++ b/net/nfc/Makefile
@@ -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
diff --git a/net/nfc/core.c b/net/nfc/core.c
index e804dc5..b6fd4e1 100644
--- a/net/nfc/core.c
+++ b/net/nfc/core.c
@@ -432,6 +432,10 @@
/* 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 @@
return 0;
err_af_nfc:
+ rawsock_exit();
+err_rawsock:
nfc_genl_exit();
err_genl:
class_unregister(&nfc_class);
@@ -448,6 +454,7 @@
static void __exit nfc_exit(void)
{
af_nfc_exit();
+ rawsock_exit();
nfc_genl_exit();
class_unregister(&nfc_class);
}
diff --git a/net/nfc/nfc.h b/net/nfc/nfc.h
index 8335f4d..aaf9832 100644
--- a/net/nfc/nfc.h
+++ b/net/nfc/nfc.h
@@ -42,6 +42,20 @@
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);
diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c
new file mode 100644
index 0000000..52de84a
--- /dev/null
+++ b/net/nfc/rawsock.c
@@ -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);
+}