diff options
Diffstat (limited to 'net/mptcp/pm_netlink.c')
| -rw-r--r-- | net/mptcp/pm_netlink.c | 2365 |
1 files changed, 2365 insertions, 0 deletions
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c new file mode 100644 index 000000000..980050f6b --- /dev/null +++ b/net/mptcp/pm_netlink.c @@ -0,0 +1,2365 @@ +// 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_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 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; + DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); +}; + +#define MPTCP_PM_ADDR_MAX 8 +#define ADD_ADDR_RETRANS_MAX 3 + +static struct pm_nl_pernet *pm_nl_get_pernet(const struct net *net) +{ + return net_generic(net, pm_nl_pernet_id); +} + +static struct pm_nl_pernet * +pm_nl_get_pernet_from_msk(const struct mptcp_sock *msk) +{ + return pm_nl_get_pernet(sock_net((struct sock *)msk)); +} + +bool mptcp_addresses_equal(const struct mptcp_addr_info *a, + const 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 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, + const 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 (mptcp_addresses_equal(&cur, saddr, saddr->port)) + return true; + } + + return false; +} + +static bool lookup_subflow_by_daddr(const struct list_head *list, + const 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 (mptcp_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, + const struct mptcp_sock *msk) +{ + const struct sock *sk = (const struct sock *)msk; + struct mptcp_pm_addr_entry *entry, *ret = NULL; + + msk_owned_by_me(msk); + + rcu_read_lock(); + list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { + if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) + continue; + + if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) + 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; + } + + ret = entry; + break; + } + rcu_read_unlock(); + return ret; +} + +static struct mptcp_pm_addr_entry * +select_signal_address(struct pm_nl_pernet *pernet, const struct mptcp_sock *msk) +{ + struct mptcp_pm_addr_entry *entry, *ret = NULL; + + 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 (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) + continue; + + if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) + continue; + + ret = entry; + break; + } + rcu_read_unlock(); + return ret; +} + +unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk) +{ + const struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); + + 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(const struct mptcp_sock *msk) +{ + struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); + + 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(const struct mptcp_sock *msk) +{ + struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); + + return READ_ONCE(pernet->subflows_max); +} +EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max); + +unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk) +{ + struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); + + return READ_ONCE(pernet->local_addr_max); +} +EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max); + +bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk) +{ + struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); + + if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) || + (find_next_and_bit(pernet->id_bitmap, msk->pm.id_avail_bitmap, + MPTCP_PM_MAX_ADDR_ID + 1, 0) == MPTCP_PM_MAX_ADDR_ID + 1)) { + WRITE_ONCE(msk->pm.work_pending, false); + return false; + } + return true; +} + +struct mptcp_pm_add_entry * +mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, + const 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 (mptcp_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 (mptcp_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, + const 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; +} + +bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, + const 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); + + add_entry = mptcp_lookup_anno_list_by_saddr(msk, &entry->addr); + + if (add_entry) { + if (mptcp_pm_is_kernel(msk)) + return false; + + sk_reset_timer(sk, &add_entry->add_timer, + jiffies + mptcp_get_add_addr_timeout(net)); + return true; + } + + 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(const struct mptcp_addr_info *addrs, unsigned int nr, + const struct mptcp_addr_info *addr) +{ + int i; + + for (i = 0; i < nr; i++) { + if (addrs[i].id == addr->id) + 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) +{ + bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0); + 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); + remote_address((struct sock_common *)sk, &remote); + + /* Non-fullmesh endpoint, fill in the single entry + * corresponding to the primary MPC subflow remote address + */ + if (!fullmesh) { + if (deny_id0) + return 0; + + 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, &addrs[i]); + addrs[i].id = subflow->remote_id; + if (deny_id0 && !addrs[i].id) + continue; + + if (!lookup_address_in_vec(addrs, i, &addrs[i]) && + msk->pm.subflows < subflows_max) { + msk->pm.subflows++; + i++; + } + } + } + + return i; +} + +static void __mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, + bool prio, bool backup) +{ + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + bool slow; + + pr_debug("send ack for %s", + prio ? "mp_prio" : (mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr")); + + slow = lock_sock_fast(ssk); + if (prio) { + if (subflow->backup != backup) + msk->last_snd = NULL; + + subflow->send_mp_prio = 1; + subflow->backup = backup; + subflow->request_bkup = backup; + } + + __mptcp_subflow_send_ack(ssk); + unlock_sock_fast(ssk, slow); +} + +static void mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, + bool prio, bool backup) +{ + spin_unlock_bh(&msk->pm.lock); + __mptcp_pm_send_ack(msk, subflow, prio, backup); + spin_lock_bh(&msk->pm.lock); +} + +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 struct mptcp_pm_addr_entry * +__lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info, + bool lookup_by_id) +{ + struct mptcp_pm_addr_entry *entry; + + list_for_each_entry(entry, &pernet->local_addr_list, list) { + if ((!lookup_by_id && + mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) || + (lookup_by_id && entry->addr.id == info->id)) + 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 = pm_nl_get_pernet(sock_net(sk)); + + 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); + + /* do lazy endpoint usage accounting for the MPC subflows */ + if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) { + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(msk->first); + struct mptcp_pm_addr_entry *entry; + struct mptcp_addr_info mpc_addr; + bool backup = false; + + local_address((struct sock_common *)msk->first, &mpc_addr); + rcu_read_lock(); + entry = __lookup_addr(pernet, &mpc_addr, false); + if (entry) { + __clear_bit(entry->addr.id, msk->pm.id_avail_bitmap); + msk->mpc_endpoint_id = entry->addr.id; + backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); + } + rcu_read_unlock(); + + if (backup) + mptcp_pm_send_ack(msk, subflow, true, backup); + + msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED); + } + + 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); + + /* due to racing events on both ends we can reach here while + * previous add address is still running: if we invoke now + * mptcp_pm_announce_addr(), that will fail and the + * corresponding id will be marked as used. + * Instead let the PM machinery reschedule us when the + * current address announce will be completed. + */ + if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL)) + return; + + if (local) { + if (mptcp_pm_alloc_anno_list(msk, local)) { + __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); + msk->pm.add_addr_signaled++; + mptcp_pm_announce_addr(msk, &local->addr, false); + mptcp_pm_nl_addr_send_ack(msk); + } + } + } + + /* check if should create a new subflow */ + while (msk->pm.local_addr_used < local_addr_max && + msk->pm.subflows < subflows_max) { + struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; + bool fullmesh; + int i, nr; + + local = select_local_address(pernet, msk); + if (!local) + break; + + fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH); + + msk->pm.local_addr_used++; + nr = fill_remote_addresses_vec(msk, fullmesh, addrs); + if (nr) + __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); + 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); + } + mptcp_pm_nl_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 = pm_nl_get_pernet_from_msk(msk); + subflows_max = mptcp_pm_get_subflows_max(msk); + + rcu_read_lock(); + 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; + 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; + mptcp_pm_announce_addr(msk, &remote, true); + mptcp_pm_nl_addr_send_ack(msk); + + if (lookup_subflow_by_daddr(&msk->conn_list, &remote)) + return; + + /* pick id 0 port, if none is provided the remote address */ + if (!remote.port) + 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); +} + +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; + + subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); + if (subflow) + mptcp_pm_send_ack(msk, subflow, false, false); +} + +int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, + struct mptcp_addr_info *addr, + struct mptcp_addr_info *rem, + 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 mptcp_addr_info local, remote; + + local_address((struct sock_common *)ssk, &local); + if (!mptcp_addresses_equal(&local, addr, addr->port)) + continue; + + if (rem && rem->family != AF_UNSPEC) { + remote_address((struct sock_common *)ssk, &remote); + if (!mptcp_addresses_equal(&remote, rem, rem->port)) + continue; + } + + __mptcp_pm_send_ack(msk, subflow, true, bkup); + return 0; + } + + return -EINVAL; +} + +static bool mptcp_local_id_match(const struct mptcp_sock *msk, u8 local_id, u8 id) +{ + return local_id == id || (!local_id && msk->mpc_endpoint_id == id); +} + +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++) { + u8 rm_id = rm_list->ids[i]; + bool removed = false; + + mptcp_for_each_subflow_safe(msk, subflow, tmp) { + 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 && subflow->remote_id != rm_id) + continue; + if (rm_type == MPTCP_MIB_RMSUBFLOW && !mptcp_local_id_match(msk, id, rm_id)) + continue; + + pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u", + rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", + i, rm_id, subflow->local_id, subflow->remote_id, + msk->mpc_endpoint_id); + spin_unlock_bh(&msk->pm.lock); + mptcp_subflow_shutdown(sk, ssk, how); + + /* the following takes care of updating the subflows counter */ + mptcp_close_ssk(sk, ssk, subflow); + spin_lock_bh(&msk->pm.lock); + + removed = true; + __MPTCP_INC_STATS(sock_net(sk), rm_type); + } + if (rm_type == MPTCP_MIB_RMSUBFLOW) + __set_bit(rm_id ? rm_id : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap); + if (!removed) + continue; + + if (!mptcp_pm_is_kernel(msk)) + 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); + + if (!(pm->status & MPTCP_PM_WORK_MASK)) + return; + + 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; +} + +/* caller must ensure the RCU grace period is already elapsed */ +static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) +{ + if (entry->lsk) + sock_release(entry->lsk); + kfree(entry); +} + +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, *del_entry = NULL; + 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 == MPTCP_PM_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 + */ + if (!address_use_port(entry)) + entry->addr.port = 0; + list_for_each_entry(cur, &pernet->local_addr_list, list) { + if (mptcp_addresses_equal(&cur->addr, &entry->addr, + cur->addr.port || entry->addr.port)) { + /* allow replacing the exiting endpoint only if such + * endpoint is an implicit one and the user-space + * did not provide an endpoint id + */ + if (!(cur->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)) + goto out; + if (entry->addr.id) + goto out; + + pernet->addrs--; + entry->addr.id = cur->addr.id; + list_del_rcu(&cur->list); + del_entry = cur; + break; + } + } + + if (!entry->addr.id) { +find_next: + entry->addr.id = find_next_zero_bit(pernet->id_bitmap, + MPTCP_PM_MAX_ADDR_ID + 1, + pernet->next_id); + if (!entry->addr.id && pernet->next_id != 1) { + pernet->next_id = 1; + goto find_next; + } + } + + if (!entry->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++; + if (!entry->addr.port) + list_add_tail_rcu(&entry->list, &pernet->local_addr_list); + else + list_add_rcu(&entry->list, &pernet->local_addr_list); + ret = entry->addr.id; + +out: + spin_unlock_bh(&pernet->lock); + + /* just replaced an existing entry, free it */ + if (del_entry) { + synchronize_rcu(); + __mptcp_pm_release_addr_entry(del_entry); + } + return ret; +} + +static struct lock_class_key mptcp_slock_keys[2]; +static struct lock_class_key mptcp_keys[2]; + +static int mptcp_pm_nl_create_listen_socket(struct sock *sk, + struct mptcp_pm_addr_entry *entry) +{ + bool is_ipv6 = sk->sk_family == AF_INET6; + int addrlen = sizeof(struct sockaddr_in); + struct sockaddr_storage addr; + struct socket *ssock; + struct sock *newsk; + 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; + + newsk = entry->lsk->sk; + if (!newsk) + return -EINVAL; + + /* The subflow socket lock is acquired in a nested to the msk one + * in several places, even by the TCP stack, and this msk is a kernel + * socket: lockdep complains. Instead of propagating the _nested + * modifiers in several places, re-init the lock class for the msk + * socket to an mptcp specific one. + */ + sock_lock_init_class_and_name(newsk, + is_ipv6 ? "mlock-AF_INET6" : "mlock-AF_INET", + &mptcp_slock_keys[is_ipv6], + is_ipv6 ? "msk_lock-AF_INET6" : "msk_lock-AF_INET", + &mptcp_keys[is_ipv6]); + + lock_sock(newsk); + ssock = __mptcp_nmpc_socket(mptcp_sk(newsk)); + release_sock(newsk); + if (!ssock) + return -EINVAL; + + 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); + return err; + } + + inet_sk_state_store(newsk, TCP_LISTEN); + err = kernel_listen(ssock, backlog); + if (err) { + pr_warn("kernel_listen error, err=%d", err); + return err; + } + + return 0; +} + +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 (mptcp_addresses_equal(&msk_local, &skc_local, false)) + return 0; + + if (mptcp_pm_is_userspace(msk)) + return mptcp_userspace_pm_get_local_id(msk, &skc_local); + + pernet = pm_nl_get_pernet_from_msk(msk); + + rcu_read_lock(); + list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { + if (mptcp_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 = MPTCP_PM_ADDR_FLAG_IMPLICIT; + entry->lsk = NULL; + ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); + if (ret < 0) + kfree(entry); + + return ret; +} + +#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, }, + [MPTCP_PM_ATTR_TOKEN] = { .type = NLA_U32, }, + [MPTCP_PM_ATTR_LOC_ID] = { .type = NLA_U8, }, + [MPTCP_PM_ATTR_ADDR_REMOTE] = + NLA_POLICY_NESTED(mptcp_pm_addr_policy), +}; + +void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) +{ + struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); + struct sock *sk = (struct sock *)msk; + unsigned int active_max_loss_cnt; + struct net *net = sock_net(sk); + unsigned int stale_loss_cnt; + bool slow; + + stale_loss_cnt = mptcp_stale_loss_cnt(net); + if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) + return; + + /* look for another available subflow not in loss state */ + active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); + mptcp_for_each_subflow(msk, iter) { + if (iter != subflow && mptcp_subflow_active(iter) && + iter->stale_count < active_max_loss_cnt) { + /* we have some alternatives, try to mark this subflow as idle ...*/ + slow = lock_sock_fast(ssk); + if (!tcp_rtx_and_write_queues_empty(ssk)) { + subflow->stale = 1; + __mptcp_retransmit_pending_data(sk); + MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_SUBFLOWSTALE); + } + unlock_sock_fast(ssk, slow); + + /* always try to push the pending data regardless of re-injections: + * we can possibly use backup subflows now, and subflow selection + * is cheap under the msk socket lock + */ + __mptcp_push_pending(sk, 0); + return; + } + } +} + +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_pm_addr_attr(struct nlattr *tb[], + const struct nlattr *attr, + struct genl_info *info, + struct mptcp_addr_info *addr, + bool require_family) +{ + 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; + + if (tb[MPTCP_PM_ADDR_ATTR_ID]) + addr->id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); + + if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { + if (!require_family) + return err; + + NL_SET_ERR_MSG_ATTR(info->extack, attr, + "missing family"); + return -EINVAL; + } + + addr->family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); + if (addr->family != AF_INET +#if IS_ENABLED(CONFIG_MPTCP_IPV6) + && 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(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 (addr->family == AF_INET6) + addr->addr6 = nla_get_in6_addr(tb[addr_addr]); + else +#endif + addr->addr.s_addr = nla_get_in_addr(tb[addr_addr]); + + if (tb[MPTCP_PM_ADDR_ATTR_PORT]) + addr->port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); + + return err; +} + +int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, + struct mptcp_addr_info *addr) +{ + struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; + + memset(addr, 0, sizeof(*addr)); + + return mptcp_pm_parse_pm_addr_attr(tb, attr, info, addr, true); +} + +int mptcp_pm_parse_entry(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; + + memset(entry, 0, sizeof(*entry)); + + err = mptcp_pm_parse_pm_addr_attr(tb, attr, info, &entry->addr, require_family); + if (err) + return err; + + 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_FLAGS]) + entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); + + if (tb[MPTCP_PM_ADDR_ATTR_PORT]) + 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 pm_nl_get_pernet(genl_info_net(info)); +} + +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) || + mptcp_pm_is_userspace(msk)) + 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_entry(attr, info, true, &addr); + if (ret < 0) + return ret; + + if (addr.addr.port && !(addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { + GENL_SET_ERR_MSG(info, "flags must have signal when using port"); + return -EINVAL; + } + + if (addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL && + addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) { + GENL_SET_ERR_MSG(info, "flags mustn't have both signal and fullmesh"); + return -EINVAL; + } + + if (addr.flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) { + GENL_SET_ERR_MSG(info, "can't create IMPLICIT endpoint"); + return -EINVAL; + } + + entry = kzalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT); + 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"); + goto out_free; + } + } + ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); + if (ret < 0) { + GENL_SET_ERR_MSG(info, "too many addresses or duplicate one"); + goto out_free; + } + + mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); + return 0; + +out_free: + __mptcp_pm_release_addr_entry(entry); + return ret; +} + +int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, + u8 *flags, int *ifindex) +{ + struct mptcp_pm_addr_entry *entry; + struct sock *sk = (struct sock *)msk; + struct net *net = sock_net(sk); + + *flags = 0; + *ifindex = 0; + + if (id) { + if (mptcp_pm_is_userspace(msk)) + return mptcp_userspace_pm_get_flags_and_ifindex_by_id(msk, + id, + flags, + ifindex); + + rcu_read_lock(); + entry = __lookup_addr_by_id(pm_nl_get_pernet(net), id); + if (entry) { + *flags = entry->flags; + *ifindex = entry->ifindex; + } + rcu_read_unlock(); + } + + return 0; +} + +static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, + const 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, + const 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, + const struct mptcp_pm_addr_entry *entry) +{ + const struct mptcp_addr_info *addr = &entry->addr; + struct mptcp_rm_list list = { .nr = 0 }; + long s_slot = 0, s_num = 0; + struct mptcp_sock *msk; + + 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 (mptcp_pm_is_userspace(msk)) + goto next; + + 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 && + !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)); + if (remove_subflow) + mptcp_pm_remove_subflow(msk, &list); + release_sock(sk); + +next: + sock_put(sk); + cond_resched(); + } + + return 0; +} + +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) || mptcp_pm_is_userspace(msk)) + goto next; + + local_address((struct sock_common *)msk, &msk_local); + if (!mptcp_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_entry(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); + synchronize_rcu(); + __mptcp_pm_release_addr_entry(entry); + + return ret; +} + +void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list) +{ + struct mptcp_rm_list alist = { .nr = 0 }; + struct mptcp_pm_addr_entry *entry; + + list_for_each_entry(entry, rm_list, list) { + if ((remove_anno_list_by_saddr(msk, &entry->addr) || + lookup_subflow_by_saddr(&msk->conn_list, &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); + } +} + +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) && + slist.nr < MPTCP_RM_IDS_MAX) + slist.ids[slist.nr++] = entry->addr.id; + + 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; + + if (!mptcp_pm_is_userspace(msk)) { + lock_sock(sk); + mptcp_pm_remove_addrs_and_subflows(msk, rm_list); + release_sock(sk); + } + + sock_put(sk); + cond_resched(); + } +} + +/* caller must ensure the RCU grace period is already elapsed */ +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_release_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, MPTCP_PM_MAX_ADDR_ID + 1); + spin_unlock_bh(&pernet->lock); + mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); + synchronize_rcu(); + __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_entry(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 = pm_nl_get_pernet(net); + + spin_lock_bh(&pernet->lock); + for (i = id; i < MPTCP_PM_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 void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk, + struct mptcp_addr_info *addr) +{ + struct mptcp_rm_list list = { .nr = 0 }; + + list.ids[list.nr++] = addr->id; + + spin_lock_bh(&msk->pm.lock); + mptcp_pm_nl_rm_subflow_received(msk, &list); + mptcp_pm_create_subflow_or_signal_addr(msk); + spin_unlock_bh(&msk->pm.lock); +} + +static int mptcp_nl_set_flags(struct net *net, + struct mptcp_addr_info *addr, + u8 bkup, u8 changed) +{ + 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) || mptcp_pm_is_userspace(msk)) + goto next; + + lock_sock(sk); + if (changed & MPTCP_PM_ADDR_FLAG_BACKUP) + ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup); + if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH) + mptcp_pm_nl_fullmesh(msk, addr); + 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 mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }, *entry; + struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, }; + struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; + struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; + struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; + struct pm_nl_pernet *pernet = genl_info_pm_nl(info); + u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP | + MPTCP_PM_ADDR_FLAG_FULLMESH; + struct net *net = sock_net(skb->sk); + u8 bkup = 0, lookup_by_id = 0; + int ret; + + ret = mptcp_pm_parse_entry(attr, info, false, &addr); + if (ret < 0) + return ret; + + if (attr_rem) { + ret = mptcp_pm_parse_entry(attr_rem, info, false, &remote); + if (ret < 0) + return ret; + } + + if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) + bkup = 1; + if (addr.addr.family == AF_UNSPEC) { + lookup_by_id = 1; + if (!addr.addr.id) + return -EOPNOTSUPP; + } + + if (token) + return mptcp_userspace_pm_set_flags(sock_net(skb->sk), + token, &addr, &remote, bkup); + + spin_lock_bh(&pernet->lock); + entry = __lookup_addr(pernet, &addr.addr, lookup_by_id); + if (!entry) { + spin_unlock_bh(&pernet->lock); + return -EINVAL; + } + if ((addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) && + (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { + spin_unlock_bh(&pernet->lock); + return -EINVAL; + } + + changed = (addr.flags ^ entry->flags) & mask; + entry->flags = (entry->flags & ~mask) | (addr.flags & mask); + addr = *entry; + spin_unlock_bh(&pernet->lock); + + mptcp_nl_set_flags(net, &addr.addr, bkup, changed); + 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); +} + +bool mptcp_userspace_pm_active(const struct mptcp_sock *msk) +{ + return genl_has_listeners(&mptcp_genl_family, + sock_net((const struct sock *)msk), + MPTCP_PM_EV_GRP_OFFSET); +} + +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 = READ_ONCE(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; + + if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side))) + return -EMSGSIZE; + + 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 sock *ssk, + const struct mptcp_addr_info *info) +{ + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); + struct mptcp_sock *msk = mptcp_sk(subflow->conn); + struct net *net = sock_net(ssk); + 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 == 0 ? + inet_sk(ssk)->inet_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_UNS_ADMIN_PERM, + }, + { + .cmd = MPTCP_PM_CMD_DEL_ADDR, + .doit = mptcp_nl_cmd_del_addr, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = MPTCP_PM_CMD_FLUSH_ADDRS, + .doit = mptcp_nl_cmd_flush_addrs, + .flags = GENL_UNS_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_UNS_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_UNS_ADMIN_PERM, + }, + { + .cmd = MPTCP_PM_CMD_ANNOUNCE, + .doit = mptcp_nl_cmd_announce, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = MPTCP_PM_CMD_REMOVE, + .doit = mptcp_nl_cmd_remove, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = MPTCP_PM_CMD_SUBFLOW_CREATE, + .doit = mptcp_nl_cmd_sf_create, + .flags = GENL_UNS_ADMIN_PERM, + }, + { + .cmd = MPTCP_PM_CMD_SUBFLOW_DESTROY, + .doit = mptcp_nl_cmd_sf_destroy, + .flags = GENL_UNS_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), + .resv_start_op = MPTCP_PM_CMD_SUBFLOW_DESTROY + 1, + .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 = pm_nl_get_pernet(net); + + INIT_LIST_HEAD_RCU(&pernet->local_addr_list); + + /* Cit. 2 subflows ought to be enough for anybody. */ + pernet->subflows_max = 2; + pernet->next_id = 1; + pernet->stale_loss_cnt = 4; + 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 = pm_nl_get_pernet(net); + + /* net is removed from namespace list, can't race with + * other modifiers, also netns core already waited for a + * RCU grace period. + */ + __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"); +} |