diff options
| author |   Florian Westphal <fw@strlen.de> | 2020-11-30 16:36:30 +0100 |
|---|---|---|
| committer |   Jakub Kicinski <kuba@kernel.org> | 2020-12-03 12:56:03 -0800 |
| commit | 7ea851d19b23593d7601ecb8091d529f4f475bf5 (patch) | |
| tree | ee60d28532343974c65fcc8876e2341c0931e18d /include/net/tcp.h | |
| parent | security: add const qualifier to struct sock in various places (diff) | |
| download | linux-dev-7ea851d19b23593d7601ecb8091d529f4f475bf5.tar.xz linux-dev-7ea851d19b23593d7601ecb8091d529f4f475bf5.zip | |
tcp: merge 'init_req' and 'route_req' functions
The Multipath-TCP standard (RFC 8684) says that an MPTCP host should send
a TCP reset if the token in a MP_JOIN request is unknown.
At this time we don't do this, the 3whs completes and the 'new subflow'
is reset afterwards. There are two ways to allow MPTCP to send the
reset.
1. override 'send_synack' callback and emit the rst from there.
The drawback is that the request socket gets inserted into the
listeners queue just to get removed again right away.
2. Send the reset from the 'route_req' function instead.
This avoids the 'add&remove request socket', but route_req lacks the
skb that is required to send the TCP reset.
Instead of just adding the skb to that function for MPTCP sake alone,
Paolo suggested to merge init_req and route_req functions.
This saves one indirection from syn processing path and provides the skb
to the merged function at the same time.
'send reset on unknown mptcp join token' is added in next patch.
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to '')
| -rw-r--r-- | include/net/tcp.h | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h index d5d22c411918..4525d6256321 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2007,15 +2007,14 @@ struct tcp_request_sock_ops { const struct sock *sk, const struct sk_buff *skb); #endif - void (*init_req)(struct request_sock *req, - const struct sock *sk_listener, - struct sk_buff *skb); #ifdef CONFIG_SYN_COOKIES __u32 (*cookie_init_seq)(const struct sk_buff *skb, __u16 *mss); #endif - struct dst_entry *(*route_req)(const struct sock *sk, struct flowi *fl, - const struct request_sock *req); + struct dst_entry *(*route_req)(const struct sock *sk, + struct sk_buff *skb, + struct flowi *fl, + struct request_sock *req); u32 (*init_seq)(const struct sk_buff *skb); u32 (*init_ts_off)(const struct net *net, const struct sk_buff *skb); int (*send_synack)(const struct sock *sk, struct dst_entry *dst, |