1 files changed, 419 insertions, 0 deletions

diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c
new file mode 100644
index 000000000..5f1d438a0
--- /dev/null
+++ b/net/nfc/rawsock.c
@@ -0,0 +1,419 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2011 Instituto Nokia de Tecnologia
+ *
+ * Authors:
+ *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
+ *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
+ */
+
+#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 put_dev;
+	}
+
+	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)
+{
+	*(u8 *)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 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_from_msg(skb_put(skb, len), msg, 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 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_msg(skb, 0, msg, 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,
+	.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,
+	.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_TARGET_MODE_IDLE);
+		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, int kern)
+{
+	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) {
+		if (!ns_capable(net->user_ns, CAP_NET_RAW))
+			return -EPERM;
+		sock->ops = &rawsock_raw_ops;
+	} else {
+		sock->ops = &rawsock_ops;
+	}
+
+	sk = sk_alloc(net, PF_NFC, GFP_ATOMIC, nfc_proto->proto, kern);
+	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);
+}