mptcp: token: move retry to caller

Once syncookie support is added, no state will be stored anymore when the
syn/ack is generated in syncookie mode.

When the ACK comes back, the generated key will be taken from the TCP ACK,
the token is re-generated and inserted into the token tree.

This means we can't retry with a new key when the token is already taken
in the syncookie case.

Therefore, move the retry logic to the caller to prepare for syncookie
support in mptcp.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Florian Westphal
2020-07-30 21:25:51 +02:00
committed by David S. Miller
parent f8ace8d915
commit 535fb8152f
2 changed files with 12 additions and 9 deletions

View File

@@ -126,11 +126,18 @@ static void subflow_init_req(struct request_sock *req,
}
if (mp_opt.mp_capable && listener->request_mptcp) {
int err;
int err, retries = 4;
again:
do {
get_random_bytes(&subflow_req->local_key, sizeof(subflow_req->local_key));
} while (subflow_req->local_key == 0);
err = mptcp_token_new_request(req);
if (err == 0)
subflow_req->mp_capable = 1;
else if (retries-- > 0)
goto again;
subflow_req->ssn_offset = TCP_SKB_CB(skb)->seq;
} else if (mp_opt.mp_join && listener->request_mptcp) {