From c25aeb4e095355eec3beb6a2b2b30322bd6d0dd4 Mon Sep 17 00:00:00 2001 From: Geliang Tang Date: Tue, 24 Aug 2021 16:26:15 -0700 Subject: mptcp: MP_FAIL suboption sending This patch added the MP_FAIL suboption sending support. Add a new flag named send_mp_fail in struct mptcp_subflow_context. If this flag is set, send out MP_FAIL suboption. Add a new member fail_seq in struct mptcp_out_options to save the data sequence number to put into the MP_FAIL suboption. An MP_FAIL option could be included in a RST or on the subflow-level ACK. Suggested-by: Paolo Abeni Signed-off-by: Geliang Tang Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- net/mptcp/options.c | 59 ++++++++++++++++++++++++++++++++++++++++++++++++---- net/mptcp/protocol.h | 3 +++ 2 files changed, 58 insertions(+), 4 deletions(-) (limited to 'net/mptcp') diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 1a59b3045a33..f2ebdd55d3cc 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -767,7 +767,7 @@ static bool mptcp_established_options_mp_prio(struct sock *sk, return true; } -static noinline void mptcp_established_options_rst(struct sock *sk, struct sk_buff *skb, +static noinline bool mptcp_established_options_rst(struct sock *sk, struct sk_buff *skb, unsigned int *size, unsigned int remaining, struct mptcp_out_options *opts) @@ -775,12 +775,36 @@ static noinline void mptcp_established_options_rst(struct sock *sk, struct sk_bu const struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); if (remaining < TCPOLEN_MPTCP_RST) - return; + return false; *size = TCPOLEN_MPTCP_RST; opts->suboptions |= OPTION_MPTCP_RST; opts->reset_transient = subflow->reset_transient; opts->reset_reason = subflow->reset_reason; + + return true; +} + +static bool mptcp_established_options_mp_fail(struct sock *sk, + unsigned int *size, + unsigned int remaining, + struct mptcp_out_options *opts) +{ + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); + + if (likely(!subflow->send_mp_fail)) + return false; + + if (remaining < TCPOLEN_MPTCP_FAIL) + return false; + + *size = TCPOLEN_MPTCP_FAIL; + opts->suboptions |= OPTION_MPTCP_FAIL; + opts->fail_seq = subflow->map_seq; + + pr_debug("MP_FAIL fail_seq=%llu", opts->fail_seq); + + return true; } bool mptcp_established_options(struct sock *sk, struct sk_buff *skb, @@ -799,15 +823,28 @@ bool mptcp_established_options(struct sock *sk, struct sk_buff *skb, return false; if (unlikely(skb && TCP_SKB_CB(skb)->tcp_flags & TCPHDR_RST)) { - mptcp_established_options_rst(sk, skb, size, remaining, opts); + if (mptcp_established_options_mp_fail(sk, &opt_size, remaining, opts)) { + *size += opt_size; + remaining -= opt_size; + } + if (mptcp_established_options_rst(sk, skb, &opt_size, remaining, opts)) { + *size += opt_size; + remaining -= opt_size; + } return true; } snd_data_fin = mptcp_data_fin_enabled(msk); if (mptcp_established_options_mp(sk, skb, snd_data_fin, &opt_size, remaining, opts)) ret = true; - else if (mptcp_established_options_dss(sk, skb, snd_data_fin, &opt_size, remaining, opts)) + else if (mptcp_established_options_dss(sk, skb, snd_data_fin, &opt_size, remaining, opts)) { ret = true; + if (mptcp_established_options_mp_fail(sk, &opt_size, remaining, opts)) { + *size += opt_size; + remaining -= opt_size; + return true; + } + } /* we reserved enough space for the above options, and exceeding the * TCP option space would be fatal @@ -1210,6 +1247,20 @@ static u16 mptcp_make_csum(const struct mptcp_ext *mpext) void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp, struct mptcp_out_options *opts) { + if (unlikely(OPTION_MPTCP_FAIL & opts->suboptions)) { + const struct sock *ssk = (const struct sock *)tp; + struct mptcp_subflow_context *subflow; + + subflow = mptcp_subflow_ctx(ssk); + subflow->send_mp_fail = 0; + + *ptr++ = mptcp_option(MPTCPOPT_MP_FAIL, + TCPOLEN_MPTCP_FAIL, + 0, 0); + put_unaligned_be64(opts->fail_seq, ptr); + ptr += 2; + } + /* RST is mutually exclusive with everything else */ if (unlikely(OPTION_MPTCP_RST & opts->suboptions)) { *ptr++ = mptcp_option(MPTCPOPT_RST, diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index d276ce16f126..3e4a79cf520a 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -27,6 +27,7 @@ #define OPTION_MPTCP_PRIO BIT(9) #define OPTION_MPTCP_RST BIT(10) #define OPTION_MPTCP_DSS BIT(11) +#define OPTION_MPTCP_FAIL BIT(12) /* MPTCP option subtypes */ #define MPTCPOPT_MP_CAPABLE 0 @@ -68,6 +69,7 @@ #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) @@ -429,6 +431,7 @@ struct mptcp_subflow_context { mpc_map : 1, backup : 1, send_mp_prio : 1, + send_mp_fail : 1, rx_eof : 1, can_ack : 1, /* only after processing the remote a key */ disposable : 1, /* ctx can be free at ulp release time */ -- cgit v1.2.3-59-g8ed1b