/* SPDX-License-Identifier: GPL-2.0 */ /* Multipath TCP * * Copyright (c) 2017 - 2019, Intel Corporation. */ #ifndef __MPTCP_PROTOCOL_H #define __MPTCP_PROTOCOL_H #include #include #include #include #include #include #define MPTCP_SUPPORTED_VERSION 1 /* MPTCP option bits */ #define OPTION_MPTCP_MPC_SYN BIT(0) #define OPTION_MPTCP_MPC_SYNACK BIT(1) #define OPTION_MPTCP_MPC_ACK BIT(2) #define OPTION_MPTCP_MPJ_SYN BIT(3) #define OPTION_MPTCP_MPJ_SYNACK BIT(4) #define OPTION_MPTCP_MPJ_ACK BIT(5) #define OPTION_MPTCP_ADD_ADDR BIT(6) #define OPTION_MPTCP_RM_ADDR BIT(7) #define OPTION_MPTCP_FASTCLOSE BIT(8) #define OPTION_MPTCP_PRIO BIT(9) #define OPTION_MPTCP_RST BIT(10) #define OPTION_MPTCP_DSS BIT(11) #define OPTION_MPTCP_FAIL BIT(12) #define OPTION_MPTCP_CSUMREQD BIT(13) #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \ OPTION_MPTCP_MPC_ACK) #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \ OPTION_MPTCP_MPJ_ACK) /* MPTCP option subtypes */ #define MPTCPOPT_MP_CAPABLE 0 #define MPTCPOPT_MP_JOIN 1 #define MPTCPOPT_DSS 2 #define MPTCPOPT_ADD_ADDR 3 #define MPTCPOPT_RM_ADDR 4 #define MPTCPOPT_MP_PRIO 5 #define MPTCPOPT_MP_FAIL 6 #define MPTCPOPT_MP_FASTCLOSE 7 #define MPTCPOPT_RST 8 /* MPTCP suboption lengths */ #define TCPOLEN_MPTCP_MPC_SYN 4 #define TCPOLEN_MPTCP_MPC_SYNACK 12 #define TCPOLEN_MPTCP_MPC_ACK 20 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22 #define TCPOLEN_MPTCP_MPJ_SYN 12 #define TCPOLEN_MPTCP_MPJ_SYNACK 16 #define TCPOLEN_MPTCP_MPJ_ACK 24 #define TCPOLEN_MPTCP_DSS_BASE 4 #define TCPOLEN_MPTCP_DSS_ACK32 4 #define TCPOLEN_MPTCP_DSS_ACK64 8 #define TCPOLEN_MPTCP_DSS_MAP32 10 #define TCPOLEN_MPTCP_DSS_MAP64 14 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2 #define TCPOLEN_MPTCP_ADD_ADDR 16 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10 #define TCPOLEN_MPTCP_ADD_ADDR6 28 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22 #define TCPOLEN_MPTCP_PORT_LEN 2 #define TCPOLEN_MPTCP_PORT_ALIGN 2 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3 #define TCPOLEN_MPTCP_PRIO 3 #define TCPOLEN_MPTCP_PRIO_ALIGN 4 #define TCPOLEN_MPTCP_FASTCLOSE 12 #define TCPOLEN_MPTCP_RST 4 #define TCPOLEN_MPTCP_FAIL 12 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA) /* MPTCP MP_JOIN flags */ #define MPTCPOPT_BACKUP BIT(0) #define MPTCPOPT_THMAC_LEN 8 /* MPTCP MP_CAPABLE flags */ #define MPTCP_VERSION_MASK (0x0F) #define MPTCP_CAP_CHECKSUM_REQD BIT(7) #define MPTCP_CAP_EXTENSIBILITY BIT(6) #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5) #define MPTCP_CAP_HMAC_SHA256 BIT(0) #define MPTCP_CAP_FLAG_MASK (0x1F) /* MPTCP DSS flags */ #define MPTCP_DSS_DATA_FIN BIT(4) #define MPTCP_DSS_DSN64 BIT(3) #define MPTCP_DSS_HAS_MAP BIT(2) #define MPTCP_DSS_ACK64 BIT(1) #define MPTCP_DSS_HAS_ACK BIT(0) #define MPTCP_DSS_FLAG_MASK (0x1F) /* MPTCP ADD_ADDR flags */ #define MPTCP_ADDR_ECHO BIT(0) /* MPTCP MP_PRIO flags */ #define MPTCP_PRIO_BKUP BIT(0) /* MPTCP TCPRST flags */ #define MPTCP_RST_TRANSIENT BIT(0) /* MPTCP socket atomic flags */ #define MPTCP_WORK_RTX 1 #define MPTCP_FALLBACK_DONE 2 #define MPTCP_WORK_CLOSE_SUBFLOW 3 /* MPTCP socket release cb flags */ #define MPTCP_PUSH_PENDING 1 #define MPTCP_CLEAN_UNA 2 #define MPTCP_ERROR_REPORT 3 #define MPTCP_RETRANSMIT 4 #define MPTCP_FLUSH_JOIN_LIST 5 #define MPTCP_SYNC_STATE 6 #define MPTCP_SYNC_SNDBUF 7 struct mptcp_skb_cb { u64 map_seq; u64 end_seq; u32 offset; u8 has_rxtstamp:1; }; #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0])) static inline bool before64(__u64 seq1, __u64 seq2) { return (__s64)(seq1 - seq2) < 0; } #define after64(seq2, seq1) before64(seq1, seq2) struct mptcp_options_received { u64 sndr_key; u64 rcvr_key; u64 data_ack; u64 data_seq; u32 subflow_seq; u16 data_len; __sum16 csum; u16 suboptions; u32 token; u32 nonce; u16 use_map:1, dsn64:1, data_fin:1, use_ack:1, ack64:1, mpc_map:1, reset_reason:4, reset_transient:1, echo:1, backup:1, deny_join_id0:1, __unused:2; u8 join_id; u64 thmac; u8 hmac[MPTCPOPT_HMAC_LEN]; struct mptcp_addr_info addr; struct mptcp_rm_list rm_list; u64 ahmac; u64 fail_seq; }; static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) { return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | ((nib & 0xF) << 8) | field); } enum mptcp_pm_status { MPTCP_PM_ADD_ADDR_RECEIVED, MPTCP_PM_ADD_ADDR_SEND_ACK, MPTCP_PM_RM_ADDR_RECEIVED, MPTCP_PM_ESTABLISHED, MPTCP_PM_SUBFLOW_ESTABLISHED, MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is * accounted int id_avail_bitmap */ }; enum mptcp_pm_type { MPTCP_PM_TYPE_KERNEL = 0, MPTCP_PM_TYPE_USERSPACE, __MPTCP_PM_TYPE_NR, __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, }; /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) enum mptcp_addr_signal_status { MPTCP_ADD_ADDR_SIGNAL, MPTCP_ADD_ADDR_ECHO, MPTCP_RM_ADDR_SIGNAL, }; /* max value of mptcp_addr_info.id */ #define MPTCP_PM_MAX_ADDR_ID U8_MAX struct mptcp_pm_data { struct mptcp_addr_info local; struct mptcp_addr_info remote; struct list_head anno_list; struct list_head userspace_pm_local_addr_list; spinlock_t lock; /*protects the whole PM data */ u8 addr_signal; bool server_side; bool work_pending; bool accept_addr; bool accept_subflow; bool remote_deny_join_id0; u8 add_addr_signaled; u8 add_addr_accepted; u8 local_addr_used; u8 pm_type; u8 subflows; u8 status; DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); struct mptcp_rm_list rm_list_tx; struct mptcp_rm_list rm_list_rx; }; struct mptcp_pm_local { struct mptcp_addr_info addr; u8 flags; int ifindex; }; struct mptcp_pm_addr_entry { struct list_head list; struct mptcp_addr_info addr; u8 flags; int ifindex; struct socket *lsk; }; struct mptcp_data_frag { struct list_head list; u64 data_seq; u16 data_len; u16 offset; u16 overhead; u16 already_sent; struct page *page; }; /* MPTCP connection sock */ struct mptcp_sock { /* inet_connection_sock must be the first member */ struct inet_connection_sock sk; u64 local_key; /* protected by the first subflow socket lock * lockless access read */ u64 remote_key; /* same as above */ u64 write_seq; u64 bytes_sent; u64 snd_nxt; u64 bytes_received; u64 ack_seq; atomic64_t rcv_wnd_sent; u64 rcv_data_fin_seq; u64 bytes_retrans; u64 bytes_consumed; int rmem_fwd_alloc; int snd_burst; int old_wspace; u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; * recovery related fields are under data_lock * protection */ u64 bytes_acked; u64 snd_una; u64 wnd_end; u32 last_data_sent; u32 last_data_recv; u32 last_ack_recv; unsigned long timer_ival; u32 token; int rmem_released; unsigned long flags; unsigned long cb_flags; bool recovery; /* closing subflow write queue reinjected */ bool can_ack; bool fully_established; bool rcv_data_fin; bool snd_data_fin_enable; bool rcv_fastclose; bool use_64bit_ack; /* Set when we received a 64-bit DSN */ bool csum_enabled; bool allow_infinite_fallback; u8 pending_state; /* A subflow asked to set this sk_state, * protected by the msk data lock */ u8 mpc_endpoint_id; u8 recvmsg_inq:1, cork:1, nodelay:1, fastopening:1, in_accept_queue:1, free_first:1, rcvspace_init:1; u32 notsent_lowat; int keepalive_cnt; int keepalive_idle; int keepalive_intvl; struct work_struct work; struct sk_buff *ooo_last_skb; struct rb_root out_of_order_queue; struct sk_buff_head receive_queue; struct list_head conn_list; struct list_head rtx_queue; struct mptcp_data_frag *first_pending; struct list_head join_list; struct sock *first; /* The mptcp ops can safely dereference, using suitable * ONCE annotation, the subflow outside the socket * lock as such sock is freed after close(). */ struct mptcp_pm_data pm; struct mptcp_sched_ops *sched; struct { u32 space; /* bytes copied in last measurement window */ u32 copied; /* bytes copied in this measurement window */ u64 time; /* start time of measurement window */ u64 rtt_us; /* last maximum rtt of subflows */ } rcvq_space; u8 scaling_ratio; u32 subflow_id; u32 setsockopt_seq; char ca_name[TCP_CA_NAME_MAX]; }; #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) #define mptcp_for_each_subflow(__msk, __subflow) \ list_for_each_entry(__subflow, &((__msk)->conn_list), node) #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) extern struct genl_family mptcp_genl_family; static inline void msk_owned_by_me(const struct mptcp_sock *msk) { sock_owned_by_me((const struct sock *)msk); } #ifdef CONFIG_DEBUG_NET /* MPTCP-specific: we might (indirectly) call this helper with the wrong sk */ #undef tcp_sk #define tcp_sk(ptr) ({ \ typeof(ptr) _ptr = (ptr); \ WARN_ON(_ptr->sk_protocol != IPPROTO_TCP); \ container_of_const(_ptr, struct tcp_sock, inet_conn.icsk_inet.sk); \ }) #define mptcp_sk(ptr) ({ \ typeof(ptr) _ptr = (ptr); \ WARN_ON(_ptr->sk_protocol != IPPROTO_MPTCP); \ container_of_const(_ptr, struct mptcp_sock, sk.icsk_inet.sk); \ }) #else /* !CONFIG_DEBUG_NET */ #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) #endif /* the msk socket don't use the backlog, also account for the bulk * free memory */ static inline int __mptcp_rmem(const struct sock *sk) { return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); } static inline int mptcp_win_from_space(const struct sock *sk, int space) { return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); } static inline int mptcp_space_from_win(const struct sock *sk, int win) { return __tcp_space_from_win(mptcp_sk(sk)->scaling_ratio, win); } static inline int __mptcp_space(const struct sock *sk) { return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); } static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) { const struct mptcp_sock *msk = mptcp_sk(sk); return READ_ONCE(msk->first_pending); } static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) { struct mptcp_sock *msk = mptcp_sk(sk); struct mptcp_data_frag *cur; cur = msk->first_pending; return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : list_next_entry(cur, list); } static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) { const struct mptcp_sock *msk = mptcp_sk(sk); if (!msk->first_pending) return NULL; if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) return NULL; return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); } static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) { struct mptcp_sock *msk = mptcp_sk(sk); if (msk->snd_una == msk->snd_nxt) return NULL; return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); } struct csum_pseudo_header { __be64 data_seq; __be32 subflow_seq; __be16 data_len; __sum16 csum; }; struct mptcp_subflow_request_sock { struct tcp_request_sock sk; u16 mp_capable : 1, mp_join : 1, backup : 1, request_bkup : 1, csum_reqd : 1, allow_join_id0 : 1; u8 local_id; u8 remote_id; u64 local_key; u64 idsn; u32 token; u32 ssn_offset; u64 thmac; u32 local_nonce; u32 remote_nonce; struct mptcp_sock *msk; struct hlist_nulls_node token_node; }; static inline struct mptcp_subflow_request_sock * mptcp_subflow_rsk(const struct request_sock *rsk) { return (struct mptcp_subflow_request_sock *)rsk; } struct mptcp_delegated_action { struct napi_struct napi; struct list_head head; }; DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); #define MPTCP_DELEGATE_SCHEDULED 0 #define MPTCP_DELEGATE_SEND 1 #define MPTCP_DELEGATE_ACK 2 #define MPTCP_DELEGATE_SNDBUF 3 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED)) /* MPTCP subflow context */ struct mptcp_subflow_context { struct list_head node;/* conn_list of subflows */ struct_group(reset, unsigned long avg_pacing_rate; /* protected by msk socket lock */ u64 local_key; u64 remote_key; u64 idsn; u64 map_seq; u32 snd_isn; u32 token; u32 rel_write_seq; u32 map_subflow_seq; u32 ssn_offset; u32 map_data_len; __wsum map_data_csum; u32 map_csum_len; u32 request_mptcp : 1, /* send MP_CAPABLE */ request_join : 1, /* send MP_JOIN */ request_bkup : 1, mp_capable : 1, /* remote is MPTCP capable */ mp_join : 1, /* remote is JOINing */ pm_notified : 1, /* PM hook called for established status */ conn_finished : 1, map_valid : 1, map_csum_reqd : 1, map_data_fin : 1, mpc_map : 1, backup : 1, send_mp_prio : 1, send_mp_fail : 1, send_fastclose : 1, send_infinite_map : 1, remote_key_valid : 1, /* received the peer key from */ disposable : 1, /* ctx can be free at ulp release time */ stale : 1, /* unable to snd/rcv data, do not use for xmit */ valid_csum_seen : 1, /* at least one csum validated */ is_mptfo : 1, /* subflow is doing TFO */ close_event_done : 1, /* has done the post-closed part */ mpc_drop : 1, /* the MPC option has been dropped in a rtx */ __unused : 9; bool data_avail; bool scheduled; bool pm_listener; /* a listener managed by the kernel PM? */ bool fully_established; /* path validated */ u32 remote_nonce; u64 thmac; u32 local_nonce; u32 remote_token; union { u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ u64 iasn; /* initial ack sequence number, MPC subflows only */ }; s16 local_id; /* if negative not initialized yet */ u8 remote_id; u8 reset_seen:1; u8 reset_transient:1; u8 reset_reason:4; u8 stale_count; u32 subflow_id; long delegated_status; unsigned long fail_tout; ); struct list_head delegated_node; /* link into delegated_action, protected by local BH */ u32 setsockopt_seq; u32 stale_rcv_tstamp; int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf, * protected by the msk socket lock */ struct sock *tcp_sock; /* tcp sk backpointer */ struct sock *conn; /* parent mptcp_sock */ const struct inet_connection_sock_af_ops *icsk_af_ops; void (*tcp_state_change)(struct sock *sk); void (*tcp_error_report)(struct sock *sk); struct rcu_head rcu; }; static inline struct mptcp_subflow_context * mptcp_subflow_ctx(const struct sock *sk) { const struct inet_connection_sock *icsk = inet_csk(sk); /* Use RCU on icsk_ulp_data only for sock diag code */ return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; } static inline struct sock * mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) { return subflow->tcp_sock; } static inline void mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) { memset(&subflow->reset, 0, sizeof(subflow->reset)); subflow->request_mptcp = 1; WRITE_ONCE(subflow->local_id, -1); } /* Convert reset reasons in MPTCP to enum sk_rst_reason type */ static inline enum sk_rst_reason sk_rst_convert_mptcp_reason(u32 reason) { switch (reason) { case MPTCP_RST_EUNSPEC: return SK_RST_REASON_MPTCP_RST_EUNSPEC; case MPTCP_RST_EMPTCP: return SK_RST_REASON_MPTCP_RST_EMPTCP; case MPTCP_RST_ERESOURCE: return SK_RST_REASON_MPTCP_RST_ERESOURCE; case MPTCP_RST_EPROHIBIT: return SK_RST_REASON_MPTCP_RST_EPROHIBIT; case MPTCP_RST_EWQ2BIG: return SK_RST_REASON_MPTCP_RST_EWQ2BIG; case MPTCP_RST_EBADPERF: return SK_RST_REASON_MPTCP_RST_EBADPERF; case MPTCP_RST_EMIDDLEBOX: return SK_RST_REASON_MPTCP_RST_EMIDDLEBOX; default: /* It should not happen, or else errors may occur * in MPTCP layer */ return SK_RST_REASON_ERROR; } } static inline void mptcp_send_active_reset_reason(struct sock *sk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); enum sk_rst_reason reason; reason = sk_rst_convert_mptcp_reason(subflow->reset_reason); tcp_send_active_reset(sk, GFP_ATOMIC, reason); } static inline u64 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) { return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - subflow->ssn_offset - subflow->map_subflow_seq; } static inline u64 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) { return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); } void mptcp_subflow_process_delegated(struct sock *ssk, long actions); static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) { long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action); struct mptcp_delegated_action *delegated; bool schedule; /* the caller held the subflow bh socket lock */ lockdep_assert_in_softirq(); /* The implied barrier pairs with tcp_release_cb_override() * mptcp_napi_poll(), and ensures the below list check sees list * updates done prior to delegated status bits changes */ old = set_mask_bits(&subflow->delegated_status, 0, set_bits); if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) { if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node))) return; delegated = this_cpu_ptr(&mptcp_delegated_actions); schedule = list_empty(&delegated->head); list_add_tail(&subflow->delegated_node, &delegated->head); sock_hold(mptcp_subflow_tcp_sock(subflow)); if (schedule) napi_schedule(&delegated->napi); } } static inline struct mptcp_subflow_context * mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) { struct mptcp_subflow_context *ret; if (list_empty(&delegated->head)) return NULL; ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); list_del_init(&ret->delegated_node); return ret; } int mptcp_is_enabled(const struct net *net); unsigned int mptcp_get_add_addr_timeout(const struct net *net); int mptcp_is_checksum_enabled(const struct net *net); int mptcp_allow_join_id0(const struct net *net); unsigned int mptcp_stale_loss_cnt(const struct net *net); unsigned int mptcp_close_timeout(const struct sock *sk); int mptcp_get_pm_type(const struct net *net); const char *mptcp_get_scheduler(const struct net *net); void mptcp_active_disable(struct sock *sk); bool mptcp_active_should_disable(struct sock *ssk); void mptcp_active_enable(struct sock *sk); void mptcp_get_available_schedulers(char *buf, size_t maxlen); void __mptcp_subflow_fully_established(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, const struct mptcp_options_received *mp_opt); bool __mptcp_retransmit_pending_data(struct sock *sk); void mptcp_check_and_set_pending(struct sock *sk); void __mptcp_push_pending(struct sock *sk, unsigned int flags); bool mptcp_subflow_data_available(struct sock *sk); void __init mptcp_subflow_init(void); void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); void mptcp_close_ssk(struct sock *sk, struct sock *ssk, struct mptcp_subflow_context *subflow); void __mptcp_subflow_send_ack(struct sock *ssk); void mptcp_subflow_reset(struct sock *ssk); void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); void mptcp_sock_graft(struct sock *sk, struct socket *parent); struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk); bool __mptcp_close(struct sock *sk, long timeout); void mptcp_cancel_work(struct sock *sk); void __mptcp_unaccepted_force_close(struct sock *sk); void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk); void mptcp_set_state(struct sock *sk, int state); bool mptcp_addresses_equal(const struct mptcp_addr_info *a, const struct mptcp_addr_info *b, bool use_port); void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr); /* called with sk socket lock held */ int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_pm_local *local, const struct mptcp_addr_info *remote); int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, struct socket **new_sock); void mptcp_info2sockaddr(const struct mptcp_addr_info *info, struct sockaddr_storage *addr, unsigned short family); struct mptcp_sched_ops *mptcp_sched_find(const char *name); int mptcp_register_scheduler(struct mptcp_sched_ops *sched); void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched); void mptcp_sched_init(void); int mptcp_init_sched(struct mptcp_sock *msk, struct mptcp_sched_ops *sched); void mptcp_release_sched(struct mptcp_sock *msk); void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow, bool scheduled); struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk); struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk); int mptcp_sched_get_send(struct mptcp_sock *msk); int mptcp_sched_get_retrans(struct mptcp_sock *msk); static inline u64 mptcp_data_avail(const struct mptcp_sock *msk) { return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed); } static inline bool mptcp_epollin_ready(const struct sock *sk) { /* mptcp doesn't have to deal with small skbs in the receive queue, * at it can always coalesce them */ return (mptcp_data_avail(mptcp_sk(sk)) >= sk->sk_rcvlowat) || (mem_cgroup_sockets_enabled && sk->sk_memcg && mem_cgroup_under_socket_pressure(sk->sk_memcg)) || READ_ONCE(tcp_memory_pressure); } int mptcp_set_rcvlowat(struct sock *sk, int val); static inline bool __tcp_can_send(const struct sock *ssk) { /* only send if our side has not closed yet */ return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); } static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) { /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ if (subflow->request_join && !READ_ONCE(subflow->fully_established)) return false; return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); } void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); void mptcp_subflow_drop_ctx(struct sock *ssk); static inline void mptcp_subflow_tcp_fallback(struct sock *sk, struct mptcp_subflow_context *ctx) { sk->sk_data_ready = sock_def_readable; sk->sk_state_change = ctx->tcp_state_change; sk->sk_write_space = sk_stream_write_space; sk->sk_error_report = ctx->tcp_error_report; inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; } void __init mptcp_proto_init(void); #if IS_ENABLED(CONFIG_MPTCP_IPV6) int __init mptcp_proto_v6_init(void); #endif struct sock *mptcp_sk_clone_init(const struct sock *sk, const struct mptcp_options_received *mp_opt, struct sock *ssk, struct request_sock *req); void mptcp_get_options(const struct sk_buff *skb, struct mptcp_options_received *mp_opt); void mptcp_finish_connect(struct sock *sk); void __mptcp_sync_state(struct sock *sk, int state); void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout); static inline void mptcp_stop_tout_timer(struct sock *sk) { if (!inet_csk(sk)->icsk_mtup.probe_timestamp) return; sk_stop_timer(sk, &sk->sk_timer); inet_csk(sk)->icsk_mtup.probe_timestamp = 0; } static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout) { /* avoid 0 timestamp, as that means no close timeout */ inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1; } static inline void mptcp_start_tout_timer(struct sock *sk) { mptcp_set_close_tout(sk, tcp_jiffies32); mptcp_reset_tout_timer(mptcp_sk(sk), 0); } static inline bool mptcp_is_fully_established(struct sock *sk) { return inet_sk_state_load(sk) == TCP_ESTABLISHED && READ_ONCE(mptcp_sk(sk)->fully_established); } void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); void mptcp_data_ready(struct sock *sk, struct sock *ssk); bool mptcp_finish_join(struct sock *sk); bool mptcp_schedule_work(struct sock *sk); int mptcp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen); int mptcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *option); u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) { if (use_64bit) return cur_seq; return __mptcp_expand_seq(old_seq, cur_seq); } void __mptcp_check_push(struct sock *sk, struct sock *ssk); void __mptcp_data_acked(struct sock *sk); void __mptcp_error_report(struct sock *sk); bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) { return READ_ONCE(msk->snd_data_fin_enable) && READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); } static inline u32 mptcp_notsent_lowat(const struct sock *sk) { struct net *net = sock_net(sk); u32 val; val = READ_ONCE(mptcp_sk(sk)->notsent_lowat); return val ?: READ_ONCE(net->ipv4.sysctl_tcp_notsent_lowat); } static inline bool mptcp_stream_memory_free(const struct sock *sk, int wake) { const struct mptcp_sock *msk = mptcp_sk(sk); u32 notsent_bytes; notsent_bytes = READ_ONCE(msk->write_seq) - READ_ONCE(msk->snd_nxt); return (notsent_bytes << wake) < mptcp_notsent_lowat(sk); } static inline bool __mptcp_stream_is_writeable(const struct sock *sk, int wake) { return mptcp_stream_memory_free(sk, wake) && __sk_stream_is_writeable(sk, wake); } static inline void mptcp_write_space(struct sock *sk) { /* pairs with memory barrier in mptcp_poll */ smp_mb(); if (mptcp_stream_memory_free(sk, 1)) sk_stream_write_space(sk); } static inline void __mptcp_sync_sndbuf(struct sock *sk) { struct mptcp_subflow_context *subflow; int ssk_sndbuf, new_sndbuf; if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) return; new_sndbuf = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[0]); mptcp_for_each_subflow(mptcp_sk(sk), subflow) { ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf); subflow->cached_sndbuf = ssk_sndbuf; new_sndbuf += ssk_sndbuf; } /* the msk max wmem limit is * tcp wmem[2] */ WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); mptcp_write_space(sk); } /* The called held both the msk socket and the subflow socket locks, * possibly under BH */ static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf) __mptcp_sync_sndbuf(sk); } /* the caller held only the subflow socket lock, either in process or * BH context. Additionally this can be called under the msk data lock, * so we can't acquire such lock here: let the delegate action acquires * the needed locks in suitable order. */ static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf)) return; local_bh_disable(); mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF); local_bh_enable(); } void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); #define MPTCP_TOKEN_MAX_RETRIES 4 void __init mptcp_token_init(void); static inline void mptcp_token_init_request(struct request_sock *req) { mptcp_subflow_rsk(req)->token_node.pprev = NULL; } int mptcp_token_new_request(struct request_sock *req); void mptcp_token_destroy_request(struct request_sock *req); int mptcp_token_new_connect(struct sock *ssk); void mptcp_token_accept(struct mptcp_subflow_request_sock *r, struct mptcp_sock *msk); bool mptcp_token_exists(u32 token); struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, long *s_num); void mptcp_token_destroy(struct mptcp_sock *msk); void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); void __init mptcp_pm_init(void); void mptcp_pm_data_init(struct mptcp_sock *msk); void mptcp_pm_data_reset(struct mptcp_sock *msk); int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, struct mptcp_addr_info *addr); int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, bool require_family, struct mptcp_pm_addr_entry *entry); bool mptcp_pm_addr_families_match(const struct sock *sk, const struct mptcp_addr_info *loc, const struct mptcp_addr_info *rem); void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); void mptcp_pm_connection_closed(struct mptcp_sock *msk); void mptcp_pm_subflow_established(struct mptcp_sock *msk); bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct mptcp_subflow_context *subflow); void mptcp_pm_add_addr_received(const struct sock *ssk, const struct mptcp_addr_info *addr); void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, const struct mptcp_addr_info *addr); void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); bool mptcp_pm_nl_is_init_remote_addr(struct mptcp_sock *msk, const struct mptcp_addr_info *remote); void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, struct mptcp_addr_info *addr, struct mptcp_addr_info *rem, u8 bkup); bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, const struct mptcp_addr_info *addr); void mptcp_pm_free_anno_list(struct mptcp_sock *msk); bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *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 * mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, const struct mptcp_addr_info *addr); int mptcp_pm_set_flags(struct sk_buff *skb, struct genl_info *info); int mptcp_pm_nl_set_flags(struct sk_buff *skb, struct genl_info *info); int mptcp_userspace_pm_set_flags(struct sk_buff *skb, struct genl_info *info); int mptcp_pm_announce_addr(struct mptcp_sock *msk, const struct mptcp_addr_info *addr, bool echo); int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); void mptcp_free_local_addr_list(struct mptcp_sock *msk); void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, const struct sock *ssk, gfp_t gfp); void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); void mptcp_event_pm_listener(const struct sock *ssk, enum mptcp_event_type event); bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); void __mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, const struct mptcp_options_received *mp_opt); void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, struct request_sock *req); int mptcp_nl_fill_addr(struct sk_buff *skb, struct mptcp_pm_addr_entry *entry); static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) { return READ_ONCE(msk->pm.addr_signal) & (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); } static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) { return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); } static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) { return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); } static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) { return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); } static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) { return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; } static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) { return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; } static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) { u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; if (family == AF_INET6) len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; if (!echo) len += MPTCPOPT_THMAC_LEN; /* account for 2 trailing 'nop' options */ if (port) len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; return len; } static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) { if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) return -EINVAL; return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; } bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, unsigned int opt_size, unsigned int remaining, struct mptcp_addr_info *addr, bool *echo, bool *drop_other_suboptions); bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, struct mptcp_rm_list *rm_list); int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc); bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); int mptcp_pm_dump_addr(struct sk_buff *msg, struct netlink_callback *cb); int mptcp_pm_nl_dump_addr(struct sk_buff *msg, struct netlink_callback *cb); int mptcp_userspace_pm_dump_addr(struct sk_buff *msg, struct netlink_callback *cb); int mptcp_pm_get_addr(struct sk_buff *skb, struct genl_info *info); int mptcp_pm_nl_get_addr(struct sk_buff *skb, struct genl_info *info); int mptcp_userspace_pm_get_addr(struct sk_buff *skb, struct genl_info *info); static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow) { int local_id = READ_ONCE(subflow->local_id); if (local_id < 0) return 0; return local_id; } void __init mptcp_pm_nl_init(void); void mptcp_pm_nl_work(struct mptcp_sock *msk); unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); /* called under PM lock */ static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) { if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) WRITE_ONCE(msk->pm.accept_subflow, true); } static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) { spin_lock_bh(&msk->pm.lock); __mptcp_pm_close_subflow(msk); spin_unlock_bh(&msk->pm.lock); } void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) { return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); } void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) { return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); } static inline bool mptcp_check_fallback(const struct sock *sk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); struct mptcp_sock *msk = mptcp_sk(subflow->conn); return __mptcp_check_fallback(msk); } static inline void __mptcp_do_fallback(struct mptcp_sock *msk) { if (__mptcp_check_fallback(msk)) { pr_debug("TCP fallback already done (msk=%p)\n", msk); return; } set_bit(MPTCP_FALLBACK_DONE, &msk->flags); } static inline bool __mptcp_has_initial_subflow(const struct mptcp_sock *msk) { struct sock *ssk = READ_ONCE(msk->first); return ssk && ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_LISTEN)); } static inline void mptcp_do_fallback(struct sock *ssk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); struct sock *sk = subflow->conn; struct mptcp_sock *msk; msk = mptcp_sk(sk); __mptcp_do_fallback(msk); if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { gfp_t saved_allocation = ssk->sk_allocation; /* we are in a atomic (BH) scope, override ssk default for data * fin allocation */ ssk->sk_allocation = GFP_ATOMIC; ssk->sk_shutdown |= SEND_SHUTDOWN; tcp_shutdown(ssk, SEND_SHUTDOWN); ssk->sk_allocation = saved_allocation; } } #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)\n", __func__, a) static inline void mptcp_subflow_early_fallback(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow) { pr_fallback(msk); subflow->request_mptcp = 0; __mptcp_do_fallback(msk); } static inline bool mptcp_check_infinite_map(struct sk_buff *skb) { struct mptcp_ext *mpext; mpext = skb ? mptcp_get_ext(skb) : NULL; if (mpext && mpext->infinite_map) return true; return false; } static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) { return (subflow->request_mptcp || subflow->request_join); } static inline bool subflow_simultaneous_connect(struct sock *sk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); return (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING) && is_active_ssk(subflow) && !subflow->conn_finished; } #ifdef CONFIG_SYN_COOKIES void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, struct sk_buff *skb); bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, struct sk_buff *skb); void __init mptcp_join_cookie_init(void); #else static inline void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, struct sk_buff *skb) {} static inline bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, struct sk_buff *skb) { return false; } static inline void mptcp_join_cookie_init(void) {} #endif #endif /* __MPTCP_PROTOCOL_H */