#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
#include <net/tcp_states.h>
#include <linux/nfc.h>
#include <linux/export.h>
#include <linux/kcov.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_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);
if (sk->sk_state == TCP_ESTABLISHED) {
sk->sk_shutdown |= SEND_SHUTDOWN;
cancel_work_sync(&nfc_rawsock(sk)->tx_work);
rawsock_write_queue_purge(sk);
}
sock_orphan(sk);
sock_put(sk);
return 0;
}
static int rawsock_connect(struct socket *sock, struct sockaddr_unsized *_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_hardirq());
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);
kcov_remote_start_common(skb_get_kcov_handle(skb));
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);
}
kcov_remote_stop();
}
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)
{
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, &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);
}
