// SPDX-License-Identifier: GPL-2.0
/* Multipath TCP
*
* Copyright (c) 2020, Red Hat, Inc.
*/
#define pr_fmt(fmt) "MPTCP: " fmt
#include <linux/inet.h>
#include <linux/kernel.h>
#include <net/tcp.h>
#include <net/netns/generic.h>
#include <net/mptcp.h>
#include <net/genetlink.h>
#include <uapi/linux/mptcp.h>
#include "protocol.h"
#include "mib.h"
/* forward declaration */
static struct genl_family mptcp_genl_family;
static int pm_nl_pernet_id;
struct mptcp_pm_addr_entry {
struct list_head list;
struct mptcp_addr_info addr;
struct rcu_head rcu;
};
struct mptcp_pm_add_entry {
struct list_head list;
struct mptcp_addr_info addr;
struct timer_list add_timer;
struct mptcp_sock *sock;
u8 retrans_times;
};
struct pm_nl_pernet {
/* protects pernet updates */
spinlock_t lock;
struct list_head local_addr_list;
unsigned int addrs;
unsigned int add_addr_signal_max;
unsigned int add_addr_accept_max;
unsigned int local_addr_max;
unsigned int subflows_max;
unsigned int next_id;
};
#define MPTCP_PM_ADDR_MAX 8
#define ADD_ADDR_RETRANS_MAX 3
static bool addresses_equal(const struct mptcp_addr_info *a,
struct mptcp_addr_info *b, bool use_port)
{
bool addr_equals = false;
if (a->family != b->family)
return false;
if (a->family == AF_INET)
addr_equals = a->addr.s_addr == b->addr.s_addr;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
else
addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6);
#endif
if (!addr_equals)
return false;
if (!use_port)
return true;
return a->port == b->port;
}
static bool address_zero(const struct mptcp_addr_info *addr)
{
struct mptcp_addr_info zero;
memset(&zero, 0, sizeof(zero));
zero.family = addr->family;
return addresses_equal(addr, &zero, false);
}
static void local_address(const struct sock_common *skc,
struct mptcp_addr_info *addr)
{
addr->port = 0;
addr->family = skc->skc_family;
if (addr->family == AF_INET)
addr->addr.s_addr = skc->skc_rcv_saddr;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
else if (addr->family == AF_INET6)
addr->addr6 = skc->skc_v6_rcv_saddr;
#endif
}
static void remote_address(const struct sock_common *skc,
struct mptcp_addr_info *addr)
{
addr->family = skc->skc_family;
addr->port = skc->skc_dport;
if (addr->family == AF_INET)
addr->addr.s_addr = skc->skc_daddr;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
else if (addr->family == AF_INET6)
addr->addr6 = skc->skc_v6_daddr;
#endif
}
static bool lookup_subflow_by_saddr(const struct list_head *list,
struct mptcp_addr_info *saddr)
{
struct