diff options
Diffstat (limited to 'net/nfc/rawsock.c')
| -rw-r--r-- | net/nfc/rawsock.c | 432 | 
1 files changed, 432 insertions, 0 deletions
diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c new file mode 100644 index 00000000000..11c3544ea54 --- /dev/null +++ b/net/nfc/rawsock.c @@ -0,0 +1,432 @@ +/* + * 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, see <http://www.gnu.org/licenses/>. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__ + +#include <net/tcp_states.h> +#include <linux/nfc.h> +#include <linux/export.h> + +#include "nfc.h" + +static struct nfc_sock_list raw_sk_list = { +	.lock = __RW_LOCK_UNLOCKED(raw_sk_list.lock) +}; + +static void nfc_sock_link(struct nfc_sock_list *l, struct sock *sk) +{ +	write_lock(&l->lock); +	sk_add_node(sk, &l->head); +	write_unlock(&l->lock); +} + +static void nfc_sock_unlink(struct nfc_sock_list *l, struct sock *sk) +{ +	write_lock(&l->lock); +	sk_del_node_init(sk); +	write_unlock(&l->lock); +} + +static void rawsock_write_queue_purge(struct sock *sk) +{ +	pr_debug("sk=%p\n", 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) +{ +	pr_debug("sk=%p err=%d\n", 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; + +	pr_debug("sock=%p sk=%p\n", sock, sk); + +	if (!sk) +		return 0; + +	if (sock->type == SOCK_RAW) +		nfc_sock_unlink(&raw_sk_list, sk); + +	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; + +	pr_debug("sock=%p sk=%p flags=%d\n", sock, sk, flags); + +	if (!addr || len < sizeof(struct sockaddr_nfc) || +	    addr->sa_family != AF_NFC) +		return -EINVAL; + +	pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n", +		 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_next_idx - 1 || +	    addr->target_idx < dev->target_next_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) +{ +	*skb_push(skb, NFC_HEADER_SIZE) = 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()); + +	pr_debug("sk=%p err=%d\n", sk, err); + +	if (err) +		goto error; + +	err = rawsock_add_header(skb); +	if (err) +		goto error_skb; + +	err = sock_queue_rcv_skb(sk, skb); +	if (err) +		goto error_skb; + +	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_skb: +	kfree_skb(skb); + +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; + +	pr_debug("sk=%p target_idx=%u\n", 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 nfc_dev *dev = nfc_rawsock(sk)->dev; +	struct sk_buff *skb; +	int rc; + +	pr_debug("sock=%p sk=%p len=%zu\n", sock, sk, len); + +	if (msg->msg_namelen) +		return -EOPNOTSUPP; + +	if (sock->state != SS_CONNECTED) +		return -ENOTCONN; + +	skb = nfc_alloc_send_skb(dev, sk, msg->msg_flags, len, &rc); +	if (skb == NULL) +		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; + +	pr_debug("sock=%p sk=%p len=%zu flags=%d\n", sock, sk, len, flags); + +	skb = skb_recv_datagram(sk, flags, noblock, &rc); +	if (!skb) +		return rc; + +	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 const struct proto_ops rawsock_raw_ops = { +	.family         = PF_NFC, +	.owner          = THIS_MODULE, +	.release        = rawsock_release, +	.bind           = sock_no_bind, +	.connect        = sock_no_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        = sock_no_sendmsg, +	.recvmsg        = rawsock_recvmsg, +	.mmap           = sock_no_mmap, +}; + +static void rawsock_destruct(struct sock *sk) +{ +	pr_debug("sk=%p\n", 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)) { +		pr_err("Freeing alive NFC raw socket %p\n", sk); +		return; +	} +} + +static int rawsock_create(struct net *net, struct socket *sock, +			  const struct nfc_protocol *nfc_proto) +{ +	struct sock *sk; + +	pr_debug("sock=%p\n", sock); + +	if ((sock->type != SOCK_SEQPACKET) && (sock->type != SOCK_RAW)) +		return -ESOCKTNOSUPPORT; + +	if (sock->type == SOCK_RAW) +		sock->ops = &rawsock_raw_ops; +	else +		sock->ops = &rawsock_ops; + +	sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, 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; +	if (sock->type == SOCK_RAW) +		nfc_sock_link(&raw_sk_list, sk); +	else { +		INIT_WORK(&nfc_rawsock(sk)->tx_work, rawsock_tx_work); +		nfc_rawsock(sk)->tx_work_scheduled = false; +	} + +	return 0; +} + +void nfc_send_to_raw_sock(struct nfc_dev *dev, struct sk_buff *skb, +			  u8 payload_type, u8 direction) +{ +	struct sk_buff *skb_copy = NULL, *nskb; +	struct sock *sk; +	u8 *data; + +	read_lock(&raw_sk_list.lock); + +	sk_for_each(sk, &raw_sk_list.head) { +		if (!skb_copy) { +			skb_copy = __pskb_copy_fclone(skb, NFC_RAW_HEADER_SIZE, +						      GFP_ATOMIC, true); +			if (!skb_copy) +				continue; + +			data = skb_push(skb_copy, NFC_RAW_HEADER_SIZE); + +			data[0] = dev ? dev->idx : 0xFF; +			data[1] = direction & 0x01; +			data[1] |= (payload_type << 1); +		} + +		nskb = skb_clone(skb_copy, GFP_ATOMIC); +		if (!nskb) +			continue; + +		if (sock_queue_rcv_skb(sk, nskb)) +			kfree_skb(nskb); +	} + +	read_unlock(&raw_sk_list.lock); + +	kfree_skb(skb_copy); +} +EXPORT_SYMBOL(nfc_send_to_raw_sock); + +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); +}  | 
