diff options
Diffstat (limited to 'net/mptcp/protocol.h')
-rw-r--r-- | net/mptcp/protocol.h | 1132 |
1 files changed, 1132 insertions, 0 deletions
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h new file mode 100644 index 0000000000..07c5ac37d0 --- /dev/null +++ b/net/mptcp/protocol.h @@ -0,0 +1,1132 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Multipath TCP + * + * Copyright (c) 2017 - 2019, Intel Corporation. + */ + +#ifndef __MPTCP_PROTOCOL_H +#define __MPTCP_PROTOCOL_H + +#include <linux/random.h> +#include <net/tcp.h> +#include <net/inet_connection_sock.h> +#include <uapi/linux/mptcp.h> +#include <net/genetlink.h> + +#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_NOSPACE 1 +#define MPTCP_WORK_RTX 2 +#define MPTCP_FALLBACK_DONE 4 +#define MPTCP_WORK_CLOSE_SUBFLOW 5 + +/* 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_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; + u64 remote_key; + 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; + 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; + unsigned long timer_ival; + u32 token; + int rmem_released; + unsigned long flags; + unsigned long cb_flags; + unsigned long push_pending; + 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; + 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) + +static inline void msk_owned_by_me(const struct mptcp_sock *msk) +{ + sock_owned_by_me((const struct sock *)msk); +} + +#define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) + +/* 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(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 == READ_ONCE(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, + 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; +} + +enum mptcp_data_avail { + MPTCP_SUBFLOW_NODATA, + MPTCP_SUBFLOW_DATA_AVAIL, +}; + +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 */ + fully_established : 1, /* path validated */ + 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 */ + local_id_valid : 1, /* local_id is correctly initialized */ + valid_csum_seen : 1, /* at least one csum validated */ + is_mptfo : 1, /* subflow is doing TFO */ + __unused : 9; + enum mptcp_data_avail data_avail; + bool scheduled; + 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 */ + }; + u8 local_id; + 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) +{ + 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; +} + +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); +int mptcp_get_pm_type(const struct net *net); +const char *mptcp_get_scheduler(const struct net *net); +void mptcp_subflow_fully_established(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); + +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_addr_info *loc, + 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 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 && !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 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 = 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 <nr_subflows> * tcp wmem[2] */ + WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); +} + +/* 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(); +} + +static inline void mptcp_write_space(struct sock *sk) +{ + if (sk_stream_is_writeable(sk)) { + /* pairs with memory barrier in mptcp_poll */ + smp_mb(); + if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) + sk_stream_write_space(sk); + } +} + +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 sock *ssk, + 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); +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_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, + unsigned int id, + u8 *flags, int *ifindex); +int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, + u8 *flags, int *ifindex); +int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, + unsigned int id, + u8 *flags, int *ifindex); +int mptcp_pm_set_flags(struct net *net, struct nlattr *token, + struct mptcp_pm_addr_entry *loc, + struct mptcp_pm_addr_entry *rem, u8 bkup); +int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup); +int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, + struct mptcp_pm_addr_entry *loc, + struct mptcp_pm_addr_entry *rem, u8 bkup); +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); +int mptcp_pm_remove_subflow(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_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, + struct list_head *rm_list); + +void mptcp_free_local_addr_list(struct mptcp_sock *msk); +int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info); +int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info); +int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info); +int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info); + +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); + +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); + +void __init mptcp_pm_nl_init(void); +void mptcp_pm_nl_work(struct mptcp_sock *msk); +void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, + const struct mptcp_rm_list *rm_list); +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(struct mptcp_sock *msk, struct sock *ssk); +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 (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { + pr_debug("TCP fallback already done (msk=%p)", msk); + return; + } + set_bit(MPTCP_FALLBACK_DONE, &msk->flags); +} + +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)", __func__, a) + +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) && + 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 */ |