From dfc8d06030335a816d81aa92fe5d1f84d06998ad Mon Sep 17 00:00:00 2001 From: Dmytro Shytyi Date: Fri, 25 Nov 2022 23:29:50 +0100 Subject: mptcp: implement delayed seq generation for passive fastopen With fastopen in place, the first subflow socket is created before the MPC handshake completes, and we need to properly initialize the sequence numbers at MPC ACK reception. Co-developed-by: Paolo Abeni Signed-off-by: Paolo Abeni Co-developed-by: Matthieu Baerts Signed-off-by: Matthieu Baerts Signed-off-by: Dmytro Shytyi Signed-off-by: Matthieu Baerts Signed-off-by: Jakub Kicinski --- net/mptcp/Makefile | 2 +- net/mptcp/fastopen.c | 28 ++++++++++++++++++++++++++++ net/mptcp/options.c | 9 ++++++--- net/mptcp/protocol.c | 9 --------- net/mptcp/protocol.h | 16 +++++++++++++++- net/mptcp/subflow.c | 5 ++++- 6 files changed, 54 insertions(+), 15 deletions(-) create mode 100644 net/mptcp/fastopen.c (limited to 'net/mptcp') diff --git a/net/mptcp/Makefile b/net/mptcp/Makefile index 6e7df47c9584..a3829ce548f9 100644 --- a/net/mptcp/Makefile +++ b/net/mptcp/Makefile @@ -2,7 +2,7 @@ obj-$(CONFIG_MPTCP) += mptcp.o mptcp-y := protocol.o subflow.o options.o token.o crypto.o ctrl.o pm.o diag.o \ - mib.o pm_netlink.o sockopt.o pm_userspace.o + mib.o pm_netlink.o sockopt.o pm_userspace.o fastopen.o obj-$(CONFIG_SYN_COOKIES) += syncookies.o obj-$(CONFIG_INET_MPTCP_DIAG) += mptcp_diag.o diff --git a/net/mptcp/fastopen.c b/net/mptcp/fastopen.c new file mode 100644 index 000000000000..19c332af0834 --- /dev/null +++ b/net/mptcp/fastopen.c @@ -0,0 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0 +/* MPTCP Fast Open Mechanism + * + * Copyright (c) 2021-2022, Dmytro SHYTYI + */ + +#include "protocol.h" + +void mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, + const struct mptcp_options_received *mp_opt) +{ + struct sock *sk = (struct sock *)msk; + struct sk_buff *skb; + + mptcp_data_lock(sk); + skb = skb_peek_tail(&sk->sk_receive_queue); + if (skb) { + WARN_ON_ONCE(MPTCP_SKB_CB(skb)->end_seq); + pr_debug("msk %p moving seq %llx -> %llx end_seq %llx -> %llx", sk, + MPTCP_SKB_CB(skb)->map_seq, MPTCP_SKB_CB(skb)->map_seq + msk->ack_seq, + MPTCP_SKB_CB(skb)->end_seq, MPTCP_SKB_CB(skb)->end_seq + msk->ack_seq); + MPTCP_SKB_CB(skb)->map_seq += msk->ack_seq; + MPTCP_SKB_CB(skb)->end_seq += msk->ack_seq; + } + + pr_debug("msk=%p ack_seq=%llx", msk, msk->ack_seq); + mptcp_data_unlock(sk); +} diff --git a/net/mptcp/options.c b/net/mptcp/options.c index ae076468fcb9..5ded85e2c374 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -939,7 +939,7 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, subflow->mp_join && (mp_opt->suboptions & OPTIONS_MPTCP_MPJ) && !subflow->request_join) tcp_send_ack(ssk); - goto fully_established; + goto check_notify; } /* we must process OoO packets before the first subflow is fully @@ -950,6 +950,8 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, if (TCP_SKB_CB(skb)->seq != subflow->ssn_offset + 1) { if (subflow->mp_join) goto reset; + if (subflow->is_mptfo && mp_opt->suboptions & OPTION_MPTCP_MPC_ACK) + goto set_fully_established; return subflow->mp_capable; } @@ -961,7 +963,7 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, */ subflow->fully_established = 1; WRITE_ONCE(msk->fully_established, true); - goto fully_established; + goto check_notify; } /* If the first established packet does not contain MP_CAPABLE + data @@ -980,11 +982,12 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, if (mp_opt->deny_join_id0) WRITE_ONCE(msk->pm.remote_deny_join_id0, true); +set_fully_established: if (unlikely(!READ_ONCE(msk->pm.server_side))) pr_warn_once("bogus mpc option on established client sk"); mptcp_subflow_fully_established(subflow, mp_opt); -fully_established: +check_notify: /* if the subflow is not already linked into the conn_list, we can't * notify the PM: this subflow is still on the listener queue * and the PM possibly acquiring the subflow lock could race with diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 66a599d2ee19..3fa0aa44bf5b 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -36,15 +36,6 @@ struct mptcp6_sock { }; #endif -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])) - enum { MPTCP_CMSG_TS = BIT(0), MPTCP_CMSG_INQ = BIT(1), diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index b5abea3d1a9c..618ac85abaaf 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -126,6 +126,15 @@ #define MPTCP_CONNECTED 6 #define MPTCP_RESET_SCHEDULER 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; @@ -471,7 +480,9 @@ struct mptcp_subflow_context { 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 */ + valid_csum_seen : 1, /* at least one csum validated */ + is_mptfo : 1, /* subflow is doing TFO */ + __unused : 8; enum mptcp_data_avail data_avail; u32 remote_nonce; u64 thmac; @@ -829,6 +840,9 @@ void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_ void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 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); + static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) { return READ_ONCE(msk->pm.addr_signal) & diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index eca4de08ca9c..cbeb7718f092 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -664,6 +664,9 @@ void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, subflow_set_remote_key(msk, subflow, mp_opt); subflow->fully_established = 1; WRITE_ONCE(msk->fully_established, true); + + if (subflow->is_mptfo) + mptcp_fastopen_gen_msk_ackseq(msk, subflow, mp_opt); } static struct sock *subflow_syn_recv_sock(const struct sock *sk, @@ -779,7 +782,7 @@ create_child: /* with OoO packets we can reach here without ingress * mpc option */ - if (mp_opt.suboptions & OPTIONS_MPTCP_MPC) + if (mp_opt.suboptions & OPTION_MPTCP_MPC_ACK) mptcp_subflow_fully_established(ctx, &mp_opt); } else if (ctx->mp_join) { struct mptcp_sock *owner; -- cgit v1.2.3