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pm_netlink.c
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pm_netlink.c
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// 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;
u8 flags;
int ifindex;
struct socket *lsk;
};
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;
};
#define MAX_ADDR_ID 255
#define BITMAP_SZ DIV_ROUND_UP(MAX_ADDR_ID + 1, BITS_PER_LONG)
struct pm_nl_pernet {
/* protects pernet updates */
spinlock_t lock;
struct list_head local_addr_list;
unsigned int addrs;
unsigned int stale_loss_cnt;
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;
unsigned long id_bitmap[BITMAP_SZ];
};
#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) {
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);
} else if (a->family == AF_INET) {
if (ipv6_addr_v4mapped(&b->addr6))
addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3];
} else if (b->family == AF_INET) {
if (ipv6_addr_v4mapped(&a->addr6))
addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr;
#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, true);
}
static void local_address(const struct sock_common *skc,
struct mptcp_addr_info *addr)
{
addr->family = skc->skc_family;
addr->port = htons(skc->skc_num);
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 mptcp_subflow_context *subflow;
struct mptcp_addr_info cur;
struct sock_common *skc;
list_for_each_entry(subflow, list, node) {
skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow);
local_address(skc, &cur);
if (addresses_equal(&cur, saddr, saddr->port))
return true;
}
return false;
}
static bool lookup_subflow_by_daddr(const struct list_head *list,
struct mptcp_addr_info *daddr)
{
struct mptcp_subflow_context *subflow;
struct mptcp_addr_info cur;
struct sock_common *skc;
list_for_each_entry(subflow, list, node) {
skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow);
remote_address(skc, &cur);
if (addresses_equal(&cur, daddr, daddr->port))
return true;
}
return false;
}
static struct mptcp_pm_addr_entry *
select_local_address(const struct pm_nl_pernet *pernet,
struct mptcp_sock *msk)
{
struct mptcp_pm_addr_entry *entry, *ret = NULL;
struct sock *sk = (struct sock *)msk;
msk_owned_by_me(msk);
rcu_read_lock();
__mptcp_flush_join_list(msk);
list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW))
continue;
if (entry->addr.family != sk->sk_family) {
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
if ((entry->addr.family == AF_INET &&
!ipv6_addr_v4mapped(&sk->sk_v6_daddr)) ||
(sk->sk_family == AF_INET &&
!ipv6_addr_v4mapped(&entry->addr.addr6)))
#endif
continue;
}
/* avoid any address already in use by subflows and
* pending join
*/
if (!lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) {
ret = entry;
break;
}
}
rcu_read_unlock();
return ret;
}
static struct mptcp_pm_addr_entry *
select_signal_address(struct pm_nl_pernet *pernet, unsigned int pos)
{
struct mptcp_pm_addr_entry *entry, *ret = NULL;
int i = 0;
rcu_read_lock();
/* do not keep any additional per socket state, just signal
* the address list in order.
* Note: removal from the local address list during the msk life-cycle
* can lead to additional addresses not being announced.
*/
list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL))
continue;
if (i++ == pos) {
ret = entry;
break;
}
}
rcu_read_unlock();
return ret;
}
unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk)
{
struct pm_nl_pernet *pernet;
pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
return READ_ONCE(pernet->add_addr_signal_max);
}
EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max);
unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk)
{
struct pm_nl_pernet *pernet;
pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
return READ_ONCE(pernet->add_addr_accept_max);
}
EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max);
unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk)
{
struct pm_nl_pernet *pernet;
pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
return READ_ONCE(pernet->subflows_max);
}
EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max);
unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk)
{
struct pm_nl_pernet *pernet;
pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
return READ_ONCE(pernet->local_addr_max);
}
EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max);
static void check_work_pending(struct mptcp_sock *msk)
{
if (msk->pm.add_addr_signaled == mptcp_pm_get_add_addr_signal_max(msk) &&
(msk->pm.local_addr_used == mptcp_pm_get_local_addr_max(msk) ||
msk->pm.subflows == mptcp_pm_get_subflows_max(msk)))
WRITE_ONCE(msk->pm.work_pending, false);
}
struct mptcp_pm_add_entry *
mptcp_lookup_anno_list_by_saddr(struct mptcp_sock *msk,
struct mptcp_addr_info *addr)
{
struct mptcp_pm_add_entry *entry;
lockdep_assert_held(&msk->pm.lock);
list_for_each_entry(entry, &msk->pm.anno_list, list) {
if (addresses_equal(&entry->addr, addr, true))
return entry;
}
return NULL;
}
bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk)
{
struct mptcp_pm_add_entry *entry;
struct mptcp_addr_info saddr;
bool ret = false;
local_address((struct sock_common *)sk, &saddr);
spin_lock_bh(&msk->pm.lock);
list_for_each_entry(entry, &msk->pm.anno_list, list) {
if (addresses_equal(&entry->addr, &saddr, true)) {
ret = true;
goto out;
}
}
out:
spin_unlock_bh(&msk->pm.lock);
return ret;
}
static void mptcp_pm_add_timer(struct timer_list *timer)
{
struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer);
struct mptcp_sock *msk = entry->sock;
struct sock *sk = (struct sock *)msk;
pr_debug("msk=%p", msk);
if (!msk)
return;
if (inet_sk_state_load(sk) == TCP_CLOSE)
return;
if (!entry->addr.id)
return;
if (mptcp_pm_should_add_signal_addr(msk)) {
sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8);
goto out;
}
spin_lock_bh(&msk->pm.lock);
if (!mptcp_pm_should_add_signal_addr(msk)) {
pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id);
mptcp_pm_announce_addr(msk, &entry->addr, false);
mptcp_pm_add_addr_send_ack(msk);
entry->retrans_times++;
}
if (entry->retrans_times < ADD_ADDR_RETRANS_MAX)
sk_reset_timer(sk, timer,
jiffies + mptcp_get_add_addr_timeout(sock_net(sk)));
spin_unlock_bh(&msk->pm.lock);
if (entry->retrans_times == ADD_ADDR_RETRANS_MAX)
mptcp_pm_subflow_established(msk);
out:
__sock_put(sk);
}
struct mptcp_pm_add_entry *
mptcp_pm_del_add_timer(struct mptcp_sock *msk,
struct mptcp_addr_info *addr, bool check_id)
{
struct mptcp_pm_add_entry *entry;
struct sock *sk = (struct sock *)msk;
spin_lock_bh(&msk->pm.lock);
entry = mptcp_lookup_anno_list_by_saddr(msk, addr);
if (entry && (!check_id || entry->addr.id == addr->id))
entry->retrans_times = ADD_ADDR_RETRANS_MAX;
spin_unlock_bh(&msk->pm.lock);
if (entry && (!check_id || entry->addr.id == addr->id))
sk_stop_timer_sync(sk, &entry->add_timer);
return entry;
}
static bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
struct mptcp_pm_addr_entry *entry)
{
struct mptcp_pm_add_entry *add_entry = NULL;
struct sock *sk = (struct sock *)msk;
struct net *net = sock_net(sk);
lockdep_assert_held(&msk->pm.lock);
if (mptcp_lookup_anno_list_by_saddr(msk, &entry->addr))
return false;
add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC);
if (!add_entry)
return false;
list_add(&add_entry->list, &msk->pm.anno_list);
add_entry->addr = entry->addr;
add_entry->sock = msk;
add_entry->retrans_times = 0;
timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0);
sk_reset_timer(sk, &add_entry->add_timer,
jiffies + mptcp_get_add_addr_timeout(net));
return true;
}
void mptcp_pm_free_anno_list(struct mptcp_sock *msk)
{
struct mptcp_pm_add_entry *entry, *tmp;
struct sock *sk = (struct sock *)msk;
LIST_HEAD(free_list);
pr_debug("msk=%p", msk);
spin_lock_bh(&msk->pm.lock);
list_splice_init(&msk->pm.anno_list, &free_list);
spin_unlock_bh(&msk->pm.lock);
list_for_each_entry_safe(entry, tmp, &free_list, list) {
sk_stop_timer_sync(sk, &entry->add_timer);
kfree(entry);
}
}
static bool lookup_address_in_vec(struct mptcp_addr_info *addrs, unsigned int nr,
struct mptcp_addr_info *addr)
{
int i;
for (i = 0; i < nr; i++) {
if (addresses_equal(&addrs[i], addr, addr->port))
return true;
}
return false;
}
/* Fill all the remote addresses into the array addrs[],
* and return the array size.
*/
static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, bool fullmesh,
struct mptcp_addr_info *addrs)
{
struct sock *sk = (struct sock *)msk, *ssk;
struct mptcp_subflow_context *subflow;
struct mptcp_addr_info remote = { 0 };
unsigned int subflows_max;
int i = 0;
subflows_max = mptcp_pm_get_subflows_max(msk);
/* Non-fullmesh endpoint, fill in the single entry
* corresponding to the primary MPC subflow remote address
*/
if (!fullmesh) {
remote_address((struct sock_common *)sk, &remote);
msk->pm.subflows++;
addrs[i++] = remote;
} else {
mptcp_for_each_subflow(msk, subflow) {
ssk = mptcp_subflow_tcp_sock(subflow);
remote_address((struct sock_common *)ssk, &remote);
if (!lookup_address_in_vec(addrs, i, &remote) &&
msk->pm.subflows < subflows_max) {
msk->pm.subflows++;
addrs[i++] = remote;
}
}
}
return i;
}
static struct mptcp_pm_addr_entry *
__lookup_addr(struct pm_nl_pernet *pernet, struct mptcp_addr_info *info)
{
struct mptcp_pm_addr_entry *entry;
list_for_each_entry(entry, &pernet->local_addr_list, list) {
if (addresses_equal(&entry->addr, info, true))
return entry;
}
return NULL;
}
static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
{
struct sock *sk = (struct sock *)msk;
struct mptcp_pm_addr_entry *local;
unsigned int add_addr_signal_max;
unsigned int local_addr_max;
struct pm_nl_pernet *pernet;
unsigned int subflows_max;
pernet = net_generic(sock_net(sk), pm_nl_pernet_id);
add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk);
local_addr_max = mptcp_pm_get_local_addr_max(msk);
subflows_max = mptcp_pm_get_subflows_max(msk);
pr_debug("local %d:%d signal %d:%d subflows %d:%d\n",
msk->pm.local_addr_used, local_addr_max,
msk->pm.add_addr_signaled, add_addr_signal_max,
msk->pm.subflows, subflows_max);
/* check first for announce */
if (msk->pm.add_addr_signaled < add_addr_signal_max) {
local = select_signal_address(pernet,
msk->pm.add_addr_signaled);
if (local) {
if (mptcp_pm_alloc_anno_list(msk, local)) {
msk->pm.add_addr_signaled++;
mptcp_pm_announce_addr(msk, &local->addr, false);
mptcp_pm_nl_addr_send_ack(msk);
}
} else {
/* pick failed, avoid fourther attempts later */
msk->pm.local_addr_used = add_addr_signal_max;
}
check_work_pending(msk);
}
/* check if should create a new subflow */
if (msk->pm.local_addr_used < local_addr_max &&
msk->pm.subflows < subflows_max &&
!READ_ONCE(msk->pm.remote_deny_join_id0)) {
local = select_local_address(pernet, msk);
if (local) {
bool fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH);
struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX];
int i, nr;
msk->pm.local_addr_used++;
check_work_pending(msk);
nr = fill_remote_addresses_vec(msk, fullmesh, addrs);
spin_unlock_bh(&msk->pm.lock);
for (i = 0; i < nr; i++)
__mptcp_subflow_connect(sk, &local->addr, &addrs[i]);
spin_lock_bh(&msk->pm.lock);
return;
}
/* lookup failed, avoid fourther attempts later */
msk->pm.local_addr_used = local_addr_max;
check_work_pending(msk);
}
}
static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk)
{
mptcp_pm_create_subflow_or_signal_addr(msk);
}
static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk)
{
mptcp_pm_create_subflow_or_signal_addr(msk);
}
/* Fill all the local addresses into the array addrs[],
* and return the array size.
*/
static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
struct mptcp_addr_info *addrs)
{
struct sock *sk = (struct sock *)msk;
struct mptcp_pm_addr_entry *entry;
struct mptcp_addr_info local;
struct pm_nl_pernet *pernet;
unsigned int subflows_max;
int i = 0;
pernet = net_generic(sock_net(sk), pm_nl_pernet_id);
subflows_max = mptcp_pm_get_subflows_max(msk);
rcu_read_lock();
__mptcp_flush_join_list(msk);
list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH))
continue;
if (entry->addr.family != sk->sk_family) {
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
if ((entry->addr.family == AF_INET &&
!ipv6_addr_v4mapped(&sk->sk_v6_daddr)) ||
(sk->sk_family == AF_INET &&
!ipv6_addr_v4mapped(&entry->addr.addr6)))
#endif
continue;
}
if (msk->pm.subflows < subflows_max) {
msk->pm.subflows++;
addrs[i++] = entry->addr;
}
}
rcu_read_unlock();
/* If the array is empty, fill in the single
* 'IPADDRANY' local address
*/
if (!i) {
memset(&local, 0, sizeof(local));
local.family = msk->pm.remote.family;
msk->pm.subflows++;
addrs[i++] = local;
}
return i;
}
static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
{
struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX];
struct sock *sk = (struct sock *)msk;
unsigned int add_addr_accept_max;
struct mptcp_addr_info remote;
unsigned int subflows_max;
bool reset_port = false;
int i, nr;
add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk);
subflows_max = mptcp_pm_get_subflows_max(msk);
pr_debug("accepted %d:%d remote family %d",
msk->pm.add_addr_accepted, add_addr_accept_max,
msk->pm.remote.family);
remote = msk->pm.remote;
if (lookup_subflow_by_daddr(&msk->conn_list, &remote))
goto add_addr_echo;
/* pick id 0 port, if none is provided the remote address */
if (!remote.port) {
reset_port = true;
remote.port = sk->sk_dport;
}
/* connect to the specified remote address, using whatever
* local address the routing configuration will pick.
*/
nr = fill_local_addresses_vec(msk, addrs);
msk->pm.add_addr_accepted++;
if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
msk->pm.subflows >= subflows_max)
WRITE_ONCE(msk->pm.accept_addr, false);
spin_unlock_bh(&msk->pm.lock);
for (i = 0; i < nr; i++)
__mptcp_subflow_connect(sk, &addrs[i], &remote);
spin_lock_bh(&msk->pm.lock);
/* be sure to echo exactly the received address */
if (reset_port)
remote.port = 0;
add_addr_echo:
mptcp_pm_announce_addr(msk, &remote, true);
mptcp_pm_nl_addr_send_ack(msk);
}
void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk)
{
struct mptcp_subflow_context *subflow;
msk_owned_by_me(msk);
lockdep_assert_held(&msk->pm.lock);
if (!mptcp_pm_should_add_signal(msk) &&
!mptcp_pm_should_rm_signal(msk))
return;
__mptcp_flush_join_list(msk);
subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node);
if (subflow) {
struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
spin_unlock_bh(&msk->pm.lock);
pr_debug("send ack for %s",
mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr");
mptcp_subflow_send_ack(ssk);
spin_lock_bh(&msk->pm.lock);
}
}
int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
struct mptcp_addr_info *addr,
u8 bkup)
{
struct mptcp_subflow_context *subflow;
pr_debug("bkup=%d", bkup);
mptcp_for_each_subflow(msk, subflow) {
struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
struct sock *sk = (struct sock *)msk;
struct mptcp_addr_info local;
local_address((struct sock_common *)ssk, &local);
if (!addresses_equal(&local, addr, addr->port))
continue;
subflow->backup = bkup;
subflow->send_mp_prio = 1;
subflow->request_bkup = bkup;
__MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPPRIOTX);
spin_unlock_bh(&msk->pm.lock);
pr_debug("send ack for mp_prio");
mptcp_subflow_send_ack(ssk);
spin_lock_bh(&msk->pm.lock);
return 0;
}
return -EINVAL;
}
static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
const struct mptcp_rm_list *rm_list,
enum linux_mptcp_mib_field rm_type)
{
struct mptcp_subflow_context *subflow, *tmp;
struct sock *sk = (struct sock *)msk;
u8 i;
pr_debug("%s rm_list_nr %d",
rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr);
msk_owned_by_me(msk);
if (sk->sk_state == TCP_LISTEN)
return;
if (!rm_list->nr)
return;
if (list_empty(&msk->conn_list))
return;
for (i = 0; i < rm_list->nr; i++) {
bool removed = false;
list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) {
struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
int how = RCV_SHUTDOWN | SEND_SHUTDOWN;
u8 id = subflow->local_id;
if (rm_type == MPTCP_MIB_RMADDR)
id = subflow->remote_id;
if (rm_list->ids[i] != id)
continue;
pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u",
rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow",
i, rm_list->ids[i], subflow->local_id, subflow->remote_id);
spin_unlock_bh(&msk->pm.lock);
mptcp_subflow_shutdown(sk, ssk, how);
mptcp_close_ssk(sk, ssk, subflow);
spin_lock_bh(&msk->pm.lock);
removed = true;
msk->pm.subflows--;
__MPTCP_INC_STATS(sock_net(sk), rm_type);
}
if (!removed)
continue;
if (rm_type == MPTCP_MIB_RMADDR) {
msk->pm.add_addr_accepted--;
WRITE_ONCE(msk->pm.accept_addr, true);
} else if (rm_type == MPTCP_MIB_RMSUBFLOW) {
msk->pm.local_addr_used--;
}
}
}
static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk)
{
mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR);
}
void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
const struct mptcp_rm_list *rm_list)
{
mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW);
}
void mptcp_pm_nl_work(struct mptcp_sock *msk)
{
struct mptcp_pm_data *pm = &msk->pm;
msk_owned_by_me(msk);
spin_lock_bh(&msk->pm.lock);
pr_debug("msk=%p status=%x", msk, pm->status);
if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) {
pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED);
mptcp_pm_nl_add_addr_received(msk);
}
if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) {
pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK);
mptcp_pm_nl_addr_send_ack(msk);
}
if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) {
pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED);
mptcp_pm_nl_rm_addr_received(msk);
}
if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) {
pm->status &= ~BIT(MPTCP_PM_ESTABLISHED);
mptcp_pm_nl_fully_established(msk);
}
if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
mptcp_pm_nl_subflow_established(msk);
}
spin_unlock_bh(&msk->pm.lock);
}
static bool address_use_port(struct mptcp_pm_addr_entry *entry)
{
return (entry->flags &
(MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) ==
MPTCP_PM_ADDR_FLAG_SIGNAL;
}
static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
struct mptcp_pm_addr_entry *entry)
{
struct mptcp_pm_addr_entry *cur;
unsigned int addr_max;
int ret = -EINVAL;
spin_lock_bh(&pernet->lock);
/* to keep the code simple, don't do IDR-like allocation for address ID,
* just bail when we exceed limits
*/
if (pernet->next_id == MAX_ADDR_ID)
pernet->next_id = 1;
if (pernet->addrs >= MPTCP_PM_ADDR_MAX)
goto out;
if (test_bit(entry->addr.id, pernet->id_bitmap))
goto out;
/* do not insert duplicate address, differentiate on port only
* singled addresses
*/
list_for_each_entry(cur, &pernet->local_addr_list, list) {
if (addresses_equal(&cur->addr, &entry->addr,
address_use_port(entry) &&
address_use_port(cur)))
goto out;
}
if (!entry->addr.id) {
find_next:
entry->addr.id = find_next_zero_bit(pernet->id_bitmap,
MAX_ADDR_ID + 1,
pernet->next_id);
if ((!entry->addr.id || entry->addr.id > MAX_ADDR_ID) &&
pernet->next_id != 1) {
pernet->next_id = 1;
goto find_next;
}
}
if (!entry->addr.id || entry->addr.id > MAX_ADDR_ID)
goto out;
__set_bit(entry->addr.id, pernet->id_bitmap);
if (entry->addr.id > pernet->next_id)
pernet->next_id = entry->addr.id;
if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) {
addr_max = pernet->add_addr_signal_max;
WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1);
}
if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
addr_max = pernet->local_addr_max;
WRITE_ONCE(pernet->local_addr_max, addr_max + 1);
}
pernet->addrs++;
list_add_tail_rcu(&entry->list, &pernet->local_addr_list);
ret = entry->addr.id;
out:
spin_unlock_bh(&pernet->lock);
return ret;
}
static int mptcp_pm_nl_create_listen_socket(struct sock *sk,
struct mptcp_pm_addr_entry *entry)
{
int addrlen = sizeof(struct sockaddr_in);
struct sockaddr_storage addr;
struct mptcp_sock *msk;
struct socket *ssock;
int backlog = 1024;
int err;
err = sock_create_kern(sock_net(sk), entry->addr.family,
SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk);
if (err)
return err;
msk = mptcp_sk(entry->lsk->sk);
if (!msk) {
err = -EINVAL;
goto out;
}
ssock = __mptcp_nmpc_socket(msk);
if (!ssock) {
err = -EINVAL;
goto out;
}
mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family);
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
if (entry->addr.family == AF_INET6)
addrlen = sizeof(struct sockaddr_in6);
#endif
err = kernel_bind(ssock, (struct sockaddr *)&addr, addrlen);
if (err) {
pr_warn("kernel_bind error, err=%d", err);
goto out;
}
err = kernel_listen(ssock, backlog);
if (err) {
pr_warn("kernel_listen error, err=%d", err);
goto out;
}
return 0;
out:
sock_release(entry->lsk);
return err;
}
int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
{
struct mptcp_pm_addr_entry *entry;
struct mptcp_addr_info skc_local;
struct mptcp_addr_info msk_local;
struct pm_nl_pernet *pernet;
int ret = -1;
if (WARN_ON_ONCE(!msk))
return -1;
/* The 0 ID mapping is defined by the first subflow, copied into the msk
* addr
*/
local_address((struct sock_common *)msk, &msk_local);
local_address((struct sock_common *)skc, &skc_local);
if (addresses_equal(&msk_local, &skc_local, false))
return 0;
if (address_zero(&skc_local))
return 0;
pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
rcu_read_lock();
list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
if (addresses_equal(&entry->addr, &skc_local, entry->addr.port)) {
ret = entry->addr.id;
break;
}
}
rcu_read_unlock();
if (ret >= 0)
return ret;
/* address not found, add to local list */
entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
if (!entry)
return -ENOMEM;
entry->addr = skc_local;
entry->addr.id = 0;
entry->addr.port = 0;
entry->ifindex = 0;
entry->flags = 0;
entry->lsk = NULL;
ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
if (ret < 0)
kfree(entry);
return ret;
}
void mptcp_pm_nl_data_init(struct mptcp_sock *msk)
{
struct mptcp_pm_data *pm = &msk->pm;
bool subflows;
subflows = !!mptcp_pm_get_subflows_max(msk);
WRITE_ONCE(pm->work_pending, (!!mptcp_pm_get_local_addr_max(msk) && subflows) ||
!!mptcp_pm_get_add_addr_signal_max(msk));
WRITE_ONCE(pm->accept_addr, !!mptcp_pm_get_add_addr_accept_max(msk) && subflows);
WRITE_ONCE(pm->accept_subflow, subflows);