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WSL2-Linux-Kernel
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WSL2-Linux-Kernel/net/mptcp/pm_netlink.c

1961 строка
48 KiB
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 rcu_head rcu;
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 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(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(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 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) {
local = select_local_address(pernet, msk);
if (local) {
struct mptcp_addr_info remote = { 0 };
msk->pm.local_addr_used++;
msk->pm.subflows++;
check_work_pending(msk);
remote_address((struct sock_common *)sk, &remote);
spin_unlock_bh(&msk->pm.lock);
__mptcp_subflow_connect(sk, &local->addr, &remote,
local->flags, local->ifindex);
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);
}
static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
{
struct sock *sk = (struct sock *)msk;
unsigned int add_addr_accept_max;
struct mptcp_addr_info remote;
struct mptcp_addr_info local;
unsigned int subflows_max;
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);
if (lookup_subflow_by_daddr(&msk->conn_list, &msk->pm.remote))
goto add_addr_echo;
msk->pm.add_addr_accepted++;
msk->pm.subflows++;
if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
msk->pm.subflows >= subflows_max)
WRITE_ONCE(msk->pm.accept_addr, false);
/* connect to the specified remote address, using whatever
* local address the routing configuration will pick.
*/
remote = msk->pm.remote;
if (!remote.port)
remote.port = sk->sk_dport;
memset(&local, 0, sizeof(local));
local.family = remote.family;
spin_unlock_bh(&msk->pm.lock);
__mptcp_subflow_connect(sk, &local, &remote, 0, 0);
spin_lock_bh(&msk->pm.lock);
add_addr_echo:
mptcp_pm_announce_addr(msk, &msk->pm.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%s%s",
mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr",
mptcp_pm_should_add_signal_ipv6(msk) ? " [ipv6]" : "",
mptcp_pm_should_add_signal_port(msk) ? " [port]" : "");
lock_sock(ssk);
tcp_send_ack(ssk);
release_sock(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");
lock_sock(ssk);
tcp_send_ack(ssk);
release_sock(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 (!rm_list->nr)
return;
if (list_empty(&msk->conn_list))
return;
for (i = 0; i < rm_list->nr; i++) {
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);
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--;
}
msk->pm.subflows--;
__MPTCP_INC_STATS(sock_net(sk), rm_type);
}
}
}
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)
{
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);
err = kernel_bind(ssock, (struct sockaddr *)&addr,
sizeof(struct sockaddr_in));
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);
}
#define MPTCP_PM_CMD_GRP_OFFSET 0
#define MPTCP_PM_EV_GRP_OFFSET 1
static const struct genl_multicast_group mptcp_pm_mcgrps[] = {
[MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, },
[MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME,
.flags = GENL_UNS_ADMIN_PERM,
},
};
static const struct nla_policy
mptcp_pm_addr_policy[MPTCP_PM_ADDR_ATTR_MAX + 1] = {
[MPTCP_PM_ADDR_ATTR_FAMILY] = { .type = NLA_U16, },
[MPTCP_PM_ADDR_ATTR_ID] = { .type = NLA_U8, },
[MPTCP_PM_ADDR_ATTR_ADDR4] = { .type = NLA_U32, },
[MPTCP_PM_ADDR_ATTR_ADDR6] =
NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
[MPTCP_PM_ADDR_ATTR_PORT] = { .type = NLA_U16 },
[MPTCP_PM_ADDR_ATTR_FLAGS] = { .type = NLA_U32 },
[MPTCP_PM_ADDR_ATTR_IF_IDX] = { .type = NLA_S32 },
};
static const struct nla_policy mptcp_pm_policy[MPTCP_PM_ATTR_MAX + 1] = {
[MPTCP_PM_ATTR_ADDR] =
NLA_POLICY_NESTED(mptcp_pm_addr_policy),
[MPTCP_PM_ATTR_RCV_ADD_ADDRS] = { .type = NLA_U32, },
[MPTCP_PM_ATTR_SUBFLOWS] = { .type = NLA_U32, },
};
static int mptcp_pm_family_to_addr(int family)
{
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
if (family == AF_INET6)
return MPTCP_PM_ADDR_ATTR_ADDR6;
#endif
return MPTCP_PM_ADDR_ATTR_ADDR4;
}
static int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
bool require_family,
struct mptcp_pm_addr_entry *entry)
{
struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1];
int err, addr_addr;
if (!attr) {
GENL_SET_ERR_MSG(info, "missing address info");
return -EINVAL;
}
/* no validation needed - was already done via nested policy */
err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr,
mptcp_pm_addr_policy, info->extack);
if (err)
return err;
memset(entry, 0, sizeof(*entry));
if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) {
if (!require_family)
goto skip_family;
NL_SET_ERR_MSG_ATTR(info->extack, attr,
"missing family");
return -EINVAL;
}
entry->addr.family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]);
if (entry->addr.family != AF_INET
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
&& entry->addr.family != AF_INET6
#endif
) {
NL_SET_ERR_MSG_ATTR(info->extack, attr,
"unknown address family");
return -EINVAL;
}
addr_addr = mptcp_pm_family_to_addr(entry->addr.family);
if (!tb[addr_addr]) {
NL_SET_ERR_MSG_ATTR(info->extack, attr,
"missing address data");
return -EINVAL;
}
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
if (entry->addr.family == AF_INET6)
entry->addr.addr6 = nla_get_in6_addr(tb[addr_addr]);
else
#endif
entry->addr.addr.s_addr = nla_get_in_addr(tb[addr_addr]);
skip_family:
if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) {
u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]);
entry->ifindex = val;
}
if (tb[MPTCP_PM_ADDR_ATTR_ID])
entry->addr.id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]);
if (tb[MPTCP_PM_ADDR_ATTR_FLAGS])
entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]);
if (tb[MPTCP_PM_ADDR_ATTR_PORT]) {
if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) {
NL_SET_ERR_MSG_ATTR(info->extack, attr,
"flags must have signal when using port");
return -EINVAL;
}
entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT]));
}
return 0;
}
static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info)
{
return net_generic(genl_info_net(info), pm_nl_pernet_id);
}
static int mptcp_nl_add_subflow_or_signal_addr(struct net *net)
{
struct mptcp_sock *msk;
long s_slot = 0, s_num = 0;
while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
struct sock *sk = (struct sock *)msk;
if (!READ_ONCE(msk->fully_established))
goto next;
lock_sock(sk);
spin_lock_bh(&msk->pm.lock);
mptcp_pm_create_subflow_or_signal_addr(msk);
spin_unlock_bh(&msk->pm.lock);
release_sock(sk);
next:
sock_put(sk);
cond_resched();
}
return 0;
}
static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
struct mptcp_pm_addr_entry addr, *entry;
int ret;
ret = mptcp_pm_parse_addr(attr, info, true, &addr);
if (ret < 0)
return ret;
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
if (!entry) {
GENL_SET_ERR_MSG(info, "can't allocate addr");
return -ENOMEM;
}
*entry = addr;
if (entry->addr.port) {
ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry);
if (ret) {
GENL_SET_ERR_MSG(info, "create listen socket error");
kfree(entry);
return ret;
}
}
ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
if (ret < 0) {
GENL_SET_ERR_MSG(info, "too many addresses or duplicate one");
if (entry->lsk)
sock_release(entry->lsk);
kfree(entry);
return ret;
}
mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk));
return 0;
}
static struct mptcp_pm_addr_entry *
__lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id)
{
struct mptcp_pm_addr_entry *entry;
list_for_each_entry(entry, &pernet->local_addr_list, list) {
if (entry->addr.id == id)
return entry;
}
return NULL;
}
static bool remove_anno_list_by_saddr(struct mptcp_sock *msk,
struct mptcp_addr_info *addr)
{
struct mptcp_pm_add_entry *entry;
entry = mptcp_pm_del_add_timer(msk, addr, false);
if (entry) {
list_del(&entry->list);
kfree(entry);
return true;
}
return false;
}
static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk,
struct mptcp_addr_info *addr,
bool force)
{
struct mptcp_rm_list list = { .nr = 0 };
bool ret;
list.ids[list.nr++] = addr->id;
ret = remove_anno_list_by_saddr(msk, addr);
if (ret || force) {
spin_lock_bh(&msk->pm.lock);
mptcp_pm_remove_addr(msk, &list);
spin_unlock_bh(&msk->pm.lock);
}
return ret;
}
static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
struct mptcp_addr_info *addr)
{
struct mptcp_sock *msk;
long s_slot = 0, s_num = 0;
struct mptcp_rm_list list = { .nr = 0 };
pr_debug("remove_id=%d", addr->id);
list.ids[list.nr++] = addr->id;
while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
struct sock *sk = (struct sock *)msk;
bool remove_subflow;
if (list_empty(&msk->conn_list)) {
mptcp_pm_remove_anno_addr(msk, addr, false);
goto next;
}
lock_sock(sk);
remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr);
mptcp_pm_remove_anno_addr(msk, addr, remove_subflow);
if (remove_subflow)
mptcp_pm_remove_subflow(msk, &list);
release_sock(sk);
next:
sock_put(sk);
cond_resched();
}
return 0;
}
struct addr_entry_release_work {
struct rcu_work rwork;
struct mptcp_pm_addr_entry *entry;
};
static void mptcp_pm_release_addr_entry(struct work_struct *work)
{
struct addr_entry_release_work *w;
struct mptcp_pm_addr_entry *entry;
w = container_of(to_rcu_work(work), struct addr_entry_release_work, rwork);
entry = w->entry;
if (entry) {
if (entry->lsk)
sock_release(entry->lsk);
kfree(entry);
}
kfree(w);
}
static void mptcp_pm_free_addr_entry(struct mptcp_pm_addr_entry *entry)
{
struct addr_entry_release_work *w;
w = kmalloc(sizeof(*w), GFP_ATOMIC);
if (w) {
INIT_RCU_WORK(&w->rwork, mptcp_pm_release_addr_entry);
w->entry = entry;
queue_rcu_work(system_wq, &w->rwork);
}
}
static int mptcp_nl_remove_id_zero_address(struct net *net,
struct mptcp_addr_info *addr)
{
struct mptcp_rm_list list = { .nr = 0 };
long s_slot = 0, s_num = 0;
struct mptcp_sock *msk;
list.ids[list.nr++] = 0;
while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
struct sock *sk = (struct sock *)msk;
struct mptcp_addr_info msk_local;
if (list_empty(&msk->conn_list))
goto next;
local_address((struct sock_common *)msk, &msk_local);
if (!addresses_equal(&msk_local, addr, addr->port))
goto next;
lock_sock(sk);
spin_lock_bh(&msk->pm.lock);
mptcp_pm_remove_addr(msk, &list);
mptcp_pm_nl_rm_subflow_received(msk, &list);
spin_unlock_bh(&msk->pm.lock);
release_sock(sk);
next:
sock_put(sk);
cond_resched();
}
return 0;
}
static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
struct mptcp_pm_addr_entry addr, *entry;
unsigned int addr_max;
int ret;
ret = mptcp_pm_parse_addr(attr, info, false, &addr);
if (ret < 0)
return ret;
/* the zero id address is special: the first address used by the msk
* always gets such an id, so different subflows can have different zero
* id addresses. Additionally zero id is not accounted for in id_bitmap.
* Let's use an 'mptcp_rm_list' instead of the common remove code.
*/
if (addr.addr.id == 0)
return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr);
spin_lock_bh(&pernet->lock);
entry = __lookup_addr_by_id(pernet, addr.addr.id);
if (!entry) {
GENL_SET_ERR_MSG(info, "address not found");
spin_unlock_bh(&pernet->lock);
return -EINVAL;
}
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_del_rcu(&entry->list);
__clear_bit(entry->addr.id, pernet->id_bitmap);
spin_unlock_bh(&pernet->lock);
mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), &entry->addr);
mptcp_pm_free_addr_entry(entry);
return ret;
}
static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
struct list_head *rm_list)
{
struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 };
struct mptcp_pm_addr_entry *entry;
list_for_each_entry(entry, rm_list, list) {
if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) &&
alist.nr < MPTCP_RM_IDS_MAX &&
slist.nr < MPTCP_RM_IDS_MAX) {
alist.ids[alist.nr++] = entry->addr.id;
slist.ids[slist.nr++] = entry->addr.id;
} else if (remove_anno_list_by_saddr(msk, &entry->addr) &&
alist.nr < MPTCP_RM_IDS_MAX) {
alist.ids[alist.nr++] = entry->addr.id;
}
}
if (alist.nr) {
spin_lock_bh(&msk->pm.lock);
mptcp_pm_remove_addr(msk, &alist);
spin_unlock_bh(&msk->pm.lock);
}
if (slist.nr)
mptcp_pm_remove_subflow(msk, &slist);
}
static void mptcp_nl_remove_addrs_list(struct net *net,
struct list_head *rm_list)
{
long s_slot = 0, s_num = 0;
struct mptcp_sock *msk;
if (list_empty(rm_list))
return;
while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
struct sock *sk = (struct sock *)msk;
lock_sock(sk);
mptcp_pm_remove_addrs_and_subflows(msk, rm_list);
release_sock(sk);
sock_put(sk);
cond_resched();
}
}
static void __flush_addrs(struct list_head *list)
{
while (!list_empty(list)) {
struct mptcp_pm_addr_entry *cur;
cur = list_entry(list->next,
struct mptcp_pm_addr_entry, list);
list_del_rcu(&cur->list);
mptcp_pm_free_addr_entry(cur);
}
}
static void __reset_counters(struct pm_nl_pernet *pernet)
{
WRITE_ONCE(pernet->add_addr_signal_max, 0);
WRITE_ONCE(pernet->add_addr_accept_max, 0);
WRITE_ONCE(pernet->local_addr_max, 0);
pernet->addrs = 0;
}
static int mptcp_nl_cmd_flush_addrs(struct sk_buff *skb, struct genl_info *info)
{
struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
LIST_HEAD(free_list);
spin_lock_bh(&pernet->lock);
list_splice_init(&pernet->local_addr_list, &free_list);
__reset_counters(pernet);
pernet->next_id = 1;
bitmap_zero(pernet->id_bitmap, MAX_ADDR_ID + 1);
spin_unlock_bh(&pernet->lock);
mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list);
__flush_addrs(&free_list);
return 0;
}
static int mptcp_nl_fill_addr(struct sk_buff *skb,
struct mptcp_pm_addr_entry *entry)
{
struct mptcp_addr_info *addr = &entry->addr;
struct nlattr *attr;
attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR);
if (!attr)
return -EMSGSIZE;
if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family))
goto nla_put_failure;
if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port)))
goto nla_put_failure;
if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id))
goto nla_put_failure;
if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags))
goto nla_put_failure;
if (entry->ifindex &&
nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex))
goto nla_put_failure;
if (addr->family == AF_INET &&
nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4,
addr->addr.s_addr))
goto nla_put_failure;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
else if (addr->family == AF_INET6 &&
nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6))
goto nla_put_failure;
#endif
nla_nest_end(skb, attr);
return 0;
nla_put_failure:
nla_nest_cancel(skb, attr);
return -EMSGSIZE;
}
static int mptcp_nl_cmd_get_addr(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
struct mptcp_pm_addr_entry addr, *entry;
struct sk_buff *msg;
void *reply;
int ret;
ret = mptcp_pm_parse_addr(attr, info, false, &addr);
if (ret < 0)
return ret;
msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (!msg)
return -ENOMEM;
reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0,
info->genlhdr->cmd);
if (!reply) {
GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
ret = -EMSGSIZE;
goto fail;
}
spin_lock_bh(&pernet->lock);
entry = __lookup_addr_by_id(pernet, addr.addr.id);
if (!entry) {
GENL_SET_ERR_MSG(info, "address not found");
ret = -EINVAL;
goto unlock_fail;
}
ret = mptcp_nl_fill_addr(msg, entry);
if (ret)
goto unlock_fail;
genlmsg_end(msg, reply);
ret = genlmsg_reply(msg, info);
spin_unlock_bh(&pernet->lock);
return ret;
unlock_fail:
spin_unlock_bh(&pernet->lock);
fail:
nlmsg_free(msg);
return ret;
}
static int mptcp_nl_cmd_dump_addrs(struct sk_buff *msg,
struct netlink_callback *cb)
{
struct net *net = sock_net(msg->sk);
struct mptcp_pm_addr_entry *entry;
struct pm_nl_pernet *pernet;
int id = cb->args[0];
void *hdr;
int i;
pernet = net_generic(net, pm_nl_pernet_id);
spin_lock_bh(&pernet->lock);
for (i = id; i < MAX_ADDR_ID + 1; i++) {
if (test_bit(i, pernet->id_bitmap)) {
entry = __lookup_addr_by_id(pernet, i);
if (!entry)
break;
if (entry->addr.id <= id)
continue;
hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, &mptcp_genl_family,
NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR);
if (!hdr)
break;
if (mptcp_nl_fill_addr(msg, entry) < 0) {
genlmsg_cancel(msg, hdr);
break;
}
id = entry->addr.id;
genlmsg_end(msg, hdr);
}
}
spin_unlock_bh(&pernet->lock);
cb->args[0] = id;
return msg->len;
}
static int parse_limit(struct genl_info *info, int id, unsigned int *limit)
{
struct nlattr *attr = info->attrs[id];
if (!attr)
return 0;
*limit = nla_get_u32(attr);
if (*limit > MPTCP_PM_ADDR_MAX) {
GENL_SET_ERR_MSG(info, "limit greater than maximum");
return -EINVAL;
}
return 0;
}
static int
mptcp_nl_cmd_set_limits(struct sk_buff *skb, struct genl_info *info)
{
struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
unsigned int rcv_addrs, subflows;
int ret;
spin_lock_bh(&pernet->lock);
rcv_addrs = pernet->add_addr_accept_max;
ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs);
if (ret)
goto unlock;
subflows = pernet->subflows_max;
ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows);
if (ret)
goto unlock;
WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs);
WRITE_ONCE(pernet->subflows_max, subflows);
unlock:
spin_unlock_bh(&pernet->lock);
return ret;
}
static int
mptcp_nl_cmd_get_limits(struct sk_buff *skb, struct genl_info *info)
{
struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
struct sk_buff *msg;
void *reply;
msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (!msg)
return -ENOMEM;
reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0,
MPTCP_PM_CMD_GET_LIMITS);
if (!reply)
goto fail;
if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS,
READ_ONCE(pernet->add_addr_accept_max)))
goto fail;
if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS,
READ_ONCE(pernet->subflows_max)))
goto fail;
genlmsg_end(msg, reply);
return genlmsg_reply(msg, info);
fail:
GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
nlmsg_free(msg);
return -EMSGSIZE;
}
static int mptcp_nl_addr_backup(struct net *net,
struct mptcp_addr_info *addr,
u8 bkup)
{
long s_slot = 0, s_num = 0;
struct mptcp_sock *msk;
int ret = -EINVAL;
while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
struct sock *sk = (struct sock *)msk;
if (list_empty(&msk->conn_list))
goto next;
lock_sock(sk);
spin_lock_bh(&msk->pm.lock);
ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, bkup);
spin_unlock_bh(&msk->pm.lock);
release_sock(sk);
next:
sock_put(sk);
cond_resched();
}
return ret;
}
static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
struct mptcp_pm_addr_entry addr, *entry;
struct net *net = sock_net(skb->sk);
u8 bkup = 0;
int ret;
ret = mptcp_pm_parse_addr(attr, info, true, &addr);
if (ret < 0)
return ret;
if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP)
bkup = 1;
list_for_each_entry(entry, &pernet->local_addr_list, list) {
if (addresses_equal(&entry->addr, &addr.addr, true)) {
ret = mptcp_nl_addr_backup(net, &entry->addr, bkup);
if (ret)
return ret;
if (bkup)
entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
else
entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP;
}
}
return 0;
}
static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp)
{
genlmsg_multicast_netns(&mptcp_genl_family, net,
nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp);
}
static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk)
{
const struct inet_sock *issk = inet_sk(ssk);
const struct mptcp_subflow_context *sf;
if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family))
return -EMSGSIZE;
switch (ssk->sk_family) {
case AF_INET:
if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr))
return -EMSGSIZE;
if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr))
return -EMSGSIZE;
break;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
case AF_INET6: {
const struct ipv6_pinfo *np = inet6_sk(ssk);
if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr))
return -EMSGSIZE;
if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr))
return -EMSGSIZE;
break;
}
#endif
default:
WARN_ON_ONCE(1);
return -EMSGSIZE;
}
if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport))
return -EMSGSIZE;
if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport))
return -EMSGSIZE;
sf = mptcp_subflow_ctx(ssk);
if (WARN_ON_ONCE(!sf))
return -EINVAL;
if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id))
return -EMSGSIZE;
if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id))
return -EMSGSIZE;
return 0;
}
static int mptcp_event_put_token_and_ssk(struct sk_buff *skb,
const struct mptcp_sock *msk,
const struct sock *ssk)
{
const struct sock *sk = (const struct sock *)msk;
const struct mptcp_subflow_context *sf;
u8 sk_err;
if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
return -EMSGSIZE;
if (mptcp_event_add_subflow(skb, ssk))
return -EMSGSIZE;
sf = mptcp_subflow_ctx(ssk);
if (WARN_ON_ONCE(!sf))
return -EINVAL;
if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup))
return -EMSGSIZE;
if (ssk->sk_bound_dev_if &&
nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if))
return -EMSGSIZE;
sk_err = ssk->sk_err;
if (sk_err && sk->sk_state == TCP_ESTABLISHED &&
nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err))
return -EMSGSIZE;
return 0;
}
static int mptcp_event_sub_established(struct sk_buff *skb,
const struct mptcp_sock *msk,
const struct sock *ssk)
{
return mptcp_event_put_token_and_ssk(skb, msk, ssk);
}
static int mptcp_event_sub_closed(struct sk_buff *skb,
const struct mptcp_sock *msk,
const struct sock *ssk)
{
const struct mptcp_subflow_context *sf;
if (mptcp_event_put_token_and_ssk(skb, msk, ssk))
return -EMSGSIZE;
sf = mptcp_subflow_ctx(ssk);
if (!sf->reset_seen)
return 0;
if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason))
return -EMSGSIZE;
if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient))
return -EMSGSIZE;
return 0;
}
static int mptcp_event_created(struct sk_buff *skb,
const struct mptcp_sock *msk,
const struct sock *ssk)
{
int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token);
if (err)
return err;
return mptcp_event_add_subflow(skb, ssk);
}
void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id)
{
struct net *net = sock_net((const struct sock *)msk);
struct nlmsghdr *nlh;
struct sk_buff *skb;
if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
return;
skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
if (!skb)
return;
nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED);
if (!nlh)
goto nla_put_failure;
if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
goto nla_put_failure;
if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id))
goto nla_put_failure;
genlmsg_end(skb, nlh);
mptcp_nl_mcast_send(net, skb, GFP_ATOMIC);
return;
nla_put_failure:
kfree_skb(skb);
}
void mptcp_event_addr_announced(const struct mptcp_sock *msk,
const struct mptcp_addr_info *info)
{
struct net *net = sock_net((const struct sock *)msk);
struct nlmsghdr *nlh;
struct sk_buff *skb;
if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
return;
skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
if (!skb)
return;
nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0,
MPTCP_EVENT_ANNOUNCED);
if (!nlh)
goto nla_put_failure;
if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
goto nla_put_failure;
if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id))
goto nla_put_failure;
if (nla_put_be16(skb, MPTCP_ATTR_DPORT, info->port))
goto nla_put_failure;
switch (info->family) {
case AF_INET:
if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr))
goto nla_put_failure;
break;
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
case AF_INET6:
if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6))
goto nla_put_failure;
break;
#endif
default:
WARN_ON_ONCE(1);
goto nla_put_failure;
}
genlmsg_end(skb, nlh);
mptcp_nl_mcast_send(net, skb, GFP_ATOMIC);
return;
nla_put_failure:
kfree_skb(skb);
}
void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
const struct sock *ssk, gfp_t gfp)
{
struct net *net = sock_net((const struct sock *)msk);
struct nlmsghdr *nlh;
struct sk_buff *skb;
if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
return;
skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp);
if (!skb)
return;
nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type);
if (!nlh)
goto nla_put_failure;
switch (type) {
case MPTCP_EVENT_UNSPEC:
WARN_ON_ONCE(1);
break;
case MPTCP_EVENT_CREATED:
case MPTCP_EVENT_ESTABLISHED:
if (mptcp_event_created(skb, msk, ssk) < 0)
goto nla_put_failure;
break;
case MPTCP_EVENT_CLOSED:
if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0)
goto nla_put_failure;
break;
case MPTCP_EVENT_ANNOUNCED:
case MPTCP_EVENT_REMOVED:
/* call mptcp_event_addr_announced()/removed instead */
WARN_ON_ONCE(1);
break;
case MPTCP_EVENT_SUB_ESTABLISHED:
case MPTCP_EVENT_SUB_PRIORITY:
if (mptcp_event_sub_established(skb, msk, ssk) < 0)
goto nla_put_failure;
break;
case MPTCP_EVENT_SUB_CLOSED:
if (mptcp_event_sub_closed(skb, msk, ssk) < 0)
goto nla_put_failure;
break;
}
genlmsg_end(skb, nlh);
mptcp_nl_mcast_send(net, skb, gfp);
return;
nla_put_failure:
kfree_skb(skb);
}
static const struct genl_small_ops mptcp_pm_ops[] = {
{
.cmd = MPTCP_PM_CMD_ADD_ADDR,
.doit = mptcp_nl_cmd_add_addr,
.flags = GENL_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_DEL_ADDR,
.doit = mptcp_nl_cmd_del_addr,
.flags = GENL_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_FLUSH_ADDRS,
.doit = mptcp_nl_cmd_flush_addrs,
.flags = GENL_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_GET_ADDR,
.doit = mptcp_nl_cmd_get_addr,
.dumpit = mptcp_nl_cmd_dump_addrs,
},
{
.cmd = MPTCP_PM_CMD_SET_LIMITS,
.doit = mptcp_nl_cmd_set_limits,
.flags = GENL_ADMIN_PERM,
},
{
.cmd = MPTCP_PM_CMD_GET_LIMITS,
.doit = mptcp_nl_cmd_get_limits,
},
{
.cmd = MPTCP_PM_CMD_SET_FLAGS,
.doit = mptcp_nl_cmd_set_flags,
.flags = GENL_ADMIN_PERM,
},
};
static struct genl_family mptcp_genl_family __ro_after_init = {
.name = MPTCP_PM_NAME,
.version = MPTCP_PM_VER,
.maxattr = MPTCP_PM_ATTR_MAX,
.policy = mptcp_pm_policy,
.netnsok = true,
.module = THIS_MODULE,
.small_ops = mptcp_pm_ops,
.n_small_ops = ARRAY_SIZE(mptcp_pm_ops),
.mcgrps = mptcp_pm_mcgrps,
.n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps),
};
static int __net_init pm_nl_init_net(struct net *net)
{
struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id);
INIT_LIST_HEAD_RCU(&pernet->local_addr_list);
pernet->next_id = 1;
spin_lock_init(&pernet->lock);
/* No need to initialize other pernet fields, the struct is zeroed at
* allocation time.
*/
return 0;
}
static void __net_exit pm_nl_exit_net(struct list_head *net_list)
{
struct net *net;
list_for_each_entry(net, net_list, exit_list) {
struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id);
/* net is removed from namespace list, can't race with
* other modifiers
*/
__flush_addrs(&pernet->local_addr_list);
}
}
static struct pernet_operations mptcp_pm_pernet_ops = {
.init = pm_nl_init_net,
.exit_batch = pm_nl_exit_net,
.id = &pm_nl_pernet_id,
.size = sizeof(struct pm_nl_pernet),
};
void __init mptcp_pm_nl_init(void)
{
if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0)
panic("Failed to register MPTCP PM pernet subsystem.\n");
if (genl_register_family(&mptcp_genl_family))
panic("Failed to register MPTCP PM netlink family\n");
}
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