linux/net/phonet/datagram.c

201 lines
4.5 KiB
C

/*
* File: datagram.c
*
* Datagram (ISI) Phonet sockets
*
* Copyright (C) 2008 Nokia Corporation.
*
* Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
* Original author: Sakari Ailus <sakari.ailus@nokia.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/kernel.h>
#include <linux/socket.h>
#include <asm/ioctls.h>
#include <net/sock.h>
#include <linux/phonet.h>
#include <net/phonet/phonet.h>
static int pn_backlog_rcv(struct sock *sk, struct sk_buff *skb);
/* associated socket ceases to exist */
static void pn_sock_close(struct sock *sk, long timeout)
{
sk_common_release(sk);
}
static int pn_ioctl(struct sock *sk, int cmd, unsigned long arg)
{
struct sk_buff *skb;
int answ;
switch (cmd) {
case SIOCINQ:
lock_sock(sk);
skb = skb_peek(&sk->sk_receive_queue);
answ = skb ? skb->len : 0;
release_sock(sk);
return put_user(answ, (int __user *)arg);
}
return -ENOIOCTLCMD;
}
/* Destroy socket. All references are gone. */
static void pn_destruct(struct sock *sk)
{
skb_queue_purge(&sk->sk_receive_queue);
}
static int pn_init(struct sock *sk)
{
sk->sk_destruct = pn_destruct;
return 0;
}
static int pn_sendmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg, size_t len)
{
struct sockaddr_pn *target;
struct sk_buff *skb;
int err;
if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|
MSG_CMSG_COMPAT))
return -EOPNOTSUPP;
if (msg->msg_name == NULL)
return -EDESTADDRREQ;
if (msg->msg_namelen < sizeof(struct sockaddr_pn))
return -EINVAL;
target = (struct sockaddr_pn *)msg->msg_name;
if (target->spn_family != AF_PHONET)
return -EAFNOSUPPORT;
skb = sock_alloc_send_skb(sk, MAX_PHONET_HEADER + len,
msg->msg_flags & MSG_DONTWAIT, &err);
if (skb == NULL)
return err;
skb_reserve(skb, MAX_PHONET_HEADER);
err = memcpy_fromiovec((void *)skb_put(skb, len), msg->msg_iov, len);
if (err < 0) {
kfree_skb(skb);
return err;
}
/*
* Fill in the Phonet header and
* finally pass the packet forwards.
*/
err = pn_skb_send(sk, skb, target);
/* If ok, return len. */
return (err >= 0) ? len : err;
}
static int pn_recvmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg, size_t len, int noblock,
int flags, int *addr_len)
{
struct sk_buff *skb = NULL;
struct sockaddr_pn sa;
int rval = -EOPNOTSUPP;
int copylen;
if (flags & ~(MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_NOSIGNAL|
MSG_CMSG_COMPAT))
goto out_nofree;
if (addr_len)
*addr_len = sizeof(sa);
skb = skb_recv_datagram(sk, flags, noblock, &rval);
if (skb == NULL)
goto out_nofree;
pn_skb_get_src_sockaddr(skb, &sa);
copylen = skb->len;
if (len < copylen) {
msg->msg_flags |= MSG_TRUNC;
copylen = len;
}
rval = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copylen);
if (rval) {
rval = -EFAULT;
goto out;
}
rval = (flags & MSG_TRUNC) ? skb->len : copylen;
if (msg->msg_name != NULL)
memcpy(msg->msg_name, &sa, sizeof(struct sockaddr_pn));
out:
skb_free_datagram(sk, skb);
out_nofree:
return rval;
}
/* Queue an skb for a sock. */
static int pn_backlog_rcv(struct sock *sk, struct sk_buff *skb)
{
int err = sock_queue_rcv_skb(sk, skb);
if (err < 0)
kfree_skb(skb);
return err ? NET_RX_DROP : NET_RX_SUCCESS;
}
/* Module registration */
static struct proto pn_proto = {
.close = pn_sock_close,
.ioctl = pn_ioctl,
.init = pn_init,
.sendmsg = pn_sendmsg,
.recvmsg = pn_recvmsg,
.backlog_rcv = pn_backlog_rcv,
.hash = pn_sock_hash,
.unhash = pn_sock_unhash,
.get_port = pn_sock_get_port,
.obj_size = sizeof(struct pn_sock),
.owner = THIS_MODULE,
.name = "PHONET",
};
static struct phonet_protocol pn_dgram_proto = {
.ops = &phonet_dgram_ops,
.prot = &pn_proto,
.sock_type = SOCK_DGRAM,
};
int __init isi_register(void)
{
return phonet_proto_register(PN_PROTO_PHONET, &pn_dgram_proto);
}
void __exit isi_unregister(void)
{
phonet_proto_unregister(PN_PROTO_PHONET, &pn_dgram_proto);
}