linux_dsm_epyc7002/net/mptcp/protocol.c
Mat Martineau f870fa0b57 mptcp: Add MPTCP socket stubs
Implements the infrastructure for MPTCP sockets.

MPTCP sockets open one in-kernel TCP socket per subflow. These subflow
sockets are only managed by the MPTCP socket that owns them and are not
visible from userspace. This commit allows a userspace program to open
an MPTCP socket with:

  sock = socket(AF_INET, SOCK_STREAM, IPPROTO_MPTCP);

The resulting socket is simply a wrapper around a single regular TCP
socket, without any of the MPTCP protocol implemented over the wire.

Co-developed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Co-developed-by: Peter Krystad <peter.krystad@linux.intel.com>
Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24 13:44:07 +01:00

143 lines
3.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Multipath TCP
*
* Copyright (c) 2017 - 2019, Intel Corporation.
*/
#define pr_fmt(fmt) "MPTCP: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <net/sock.h>
#include <net/inet_common.h>
#include <net/inet_hashtables.h>
#include <net/protocol.h>
#include <net/tcp.h>
#include <net/mptcp.h>
#include "protocol.h"
static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
{
struct mptcp_sock *msk = mptcp_sk(sk);
struct socket *subflow = msk->subflow;
if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL))
return -EOPNOTSUPP;
return sock_sendmsg(subflow, msg);
}
static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
int nonblock, int flags, int *addr_len)
{
struct mptcp_sock *msk = mptcp_sk(sk);
struct socket *subflow = msk->subflow;
if (msg->msg_flags & ~(MSG_WAITALL | MSG_DONTWAIT))
return -EOPNOTSUPP;
return sock_recvmsg(subflow, msg, flags);
}
static int mptcp_init_sock(struct sock *sk)
{
return 0;
}
static void mptcp_close(struct sock *sk, long timeout)
{
struct mptcp_sock *msk = mptcp_sk(sk);
inet_sk_state_store(sk, TCP_CLOSE);
if (msk->subflow) {
pr_debug("subflow=%p", msk->subflow->sk);
sock_release(msk->subflow);
}
sock_orphan(sk);
sock_put(sk);
}
static int mptcp_connect(struct sock *sk, struct sockaddr *saddr, int len)
{
struct mptcp_sock *msk = mptcp_sk(sk);
int err;
saddr->sa_family = AF_INET;
pr_debug("msk=%p, subflow=%p", msk, msk->subflow->sk);
err = kernel_connect(msk->subflow, saddr, len, 0);
sk->sk_state = TCP_ESTABLISHED;
return err;
}
static struct proto mptcp_prot = {
.name = "MPTCP",
.owner = THIS_MODULE,
.init = mptcp_init_sock,
.close = mptcp_close,
.accept = inet_csk_accept,
.connect = mptcp_connect,
.shutdown = tcp_shutdown,
.sendmsg = mptcp_sendmsg,
.recvmsg = mptcp_recvmsg,
.hash = inet_hash,
.unhash = inet_unhash,
.get_port = inet_csk_get_port,
.obj_size = sizeof(struct mptcp_sock),
.no_autobind = true,
};
static struct inet_protosw mptcp_protosw = {
.type = SOCK_STREAM,
.protocol = IPPROTO_MPTCP,
.prot = &mptcp_prot,
.ops = &inet_stream_ops,
};
void __init mptcp_init(void)
{
if (proto_register(&mptcp_prot, 1) != 0)
panic("Failed to register MPTCP proto.\n");
inet_register_protosw(&mptcp_protosw);
}
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
static struct proto mptcp_v6_prot;
static struct inet_protosw mptcp_v6_protosw = {
.type = SOCK_STREAM,
.protocol = IPPROTO_MPTCP,
.prot = &mptcp_v6_prot,
.ops = &inet6_stream_ops,
.flags = INET_PROTOSW_ICSK,
};
int mptcpv6_init(void)
{
int err;
mptcp_v6_prot = mptcp_prot;
strcpy(mptcp_v6_prot.name, "MPTCPv6");
mptcp_v6_prot.slab = NULL;
mptcp_v6_prot.obj_size = sizeof(struct mptcp_sock) +
sizeof(struct ipv6_pinfo);
err = proto_register(&mptcp_v6_prot, 1);
if (err)
return err;
err = inet6_register_protosw(&mptcp_v6_protosw);
if (err)
proto_unregister(&mptcp_v6_prot);
return err;
}
#endif