diff options
| author | Mat Martineau <mathew.j.martineau@linux.intel.com> | 2020-07-28 15:12:06 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-07-28 17:02:42 -0700 |
| commit | 43b54c6ee382f026fc93babf5301ec79e1c9614a (patch) | |
| tree | f7000ee2af1d5f86cbf2c30df0e814991d0cfc5c /net/mptcp/subflow.c | |
| parent | 16a9a9da17234797b01ca05024d33269872a0ae0 (diff) | |
| download | linux-43b54c6ee382f026fc93babf5301ec79e1c9614a.tar.bz2 | |
mptcp: Use full MPTCP-level disconnect state machine
RFC 8684 appendix D describes the connection state machine for
MPTCP. This patch implements the DATA_FIN / DATA_ACK exchanges and
MPTCP-level socket state changes described in that appendix, rather than
simply sending DATA_FIN along with TCP FIN when disconnecting subflows.
DATA_FIN is now sent and acknowledged before shutting down the
subflows. Received DATA_FIN information (if not part of a data packet)
is written to the MPTCP socket when the incoming DSS option is parsed by
the subflow, and the MPTCP worker is scheduled to process the
flag. DATA_FIN received as part of a full DSS mapping will be handled
when the mapping is processed.
The DATA_FIN is acknowledged by the worker if the reader is caught
up. If there is still data to be moved to the MPTCP-level queue, ack_seq
will be incremented to account for the DATA_FIN when it reaches the end
of the stream and a DATA_ACK will be sent to the peer.
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/mptcp/subflow.c')
| -rw-r--r-- | net/mptcp/subflow.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index e645483d1200..7ab2a52ad150 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -598,7 +598,8 @@ static bool validate_mapping(struct sock *ssk, struct sk_buff *skb) return true; } -static enum mapping_status get_mapping_status(struct sock *ssk) +static enum mapping_status get_mapping_status(struct sock *ssk, + struct mptcp_sock *msk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); struct mptcp_ext *mpext; @@ -648,7 +649,8 @@ static enum mapping_status get_mapping_status(struct sock *ssk) if (mpext->data_fin == 1) { if (data_len == 1) { - pr_debug("DATA_FIN with no payload"); + mptcp_update_rcv_data_fin(msk, mpext->data_seq); + pr_debug("DATA_FIN with no payload seq=%llu", mpext->data_seq); if (subflow->map_valid) { /* A DATA_FIN might arrive in a DSS * option before the previous mapping @@ -660,6 +662,9 @@ static enum mapping_status get_mapping_status(struct sock *ssk) } else { return MAPPING_DATA_FIN; } + } else { + mptcp_update_rcv_data_fin(msk, mpext->data_seq + data_len); + pr_debug("DATA_FIN with mapping seq=%llu", mpext->data_seq + data_len); } /* Adjust for DATA_FIN using 1 byte of sequence space */ @@ -748,7 +753,7 @@ static bool subflow_check_data_avail(struct sock *ssk) u64 ack_seq; u64 old_ack; - status = get_mapping_status(ssk); + status = get_mapping_status(ssk, msk); pr_debug("msk=%p ssk=%p status=%d", msk, ssk, status); if (status == MAPPING_INVALID) { ssk->sk_err = EBADMSG; |