# \[RFC v2 10/14\] tcp\_md5: Check for TCP\_MD5 after TCP Timestamps in tcp\_established\_options

- From: Christoph Paasch \<hidden\>
- Date: 2018-02-01 00:07:34 
- List: netdev
- Page: https://ratatoskr.run/netdev/2018/02/11082694
- Thread: https://ratatoskr.run/netdev/2018/02/11082699/t.md

```text
It really does not matter, because we never use TCP timestamps when
TCP_MD5 is enabled (see tcp_syn_options).

Moving TCP_MD5 a bit lower allows for easier adoption of the
tcp_extra_option framework.

Cc: Ivan Delalande <redacted>
Signed-off-by: Christoph Paasch <redacted>
Reviewed-by: Mat Martineau <redacted>
---
 net/ipv4/tcp_output.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index facbdf4fe9be..97e6aecc03eb 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -662,6 +662,13 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb
 
 	opts->options = 0;
 
+	if (likely(tp->rx_opt.tstamp_ok)) {
+		opts->options |= OPTION_TS;
+		opts->tsval = skb ? tcp_skb_timestamp(skb) + tp->tsoffset : 0;
+		opts->tsecr = tp->rx_opt.ts_recent;
+		size += TCPOLEN_TSTAMP_ALIGNED;
+	}
+
 #ifdef CONFIG_TCP_MD5SIG
 	opts->md5 = tp->af_specific->md5_lookup(sk, sk);
 	if (unlikely(opts->md5)) {
@@ -672,13 +679,6 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb
 	opts->md5 = NULL;
 #endif
 
-	if (likely(tp->rx_opt.tstamp_ok)) {
-		opts->options |= OPTION_TS;
-		opts->tsval = skb ? tcp_skb_timestamp(skb) + tp->tsoffset : 0;
-		opts->tsecr = tp->rx_opt.ts_recent;
-		size += TCPOLEN_TSTAMP_ALIGNED;
-	}
-
 	if (unlikely(!hlist_empty(&tp->tcp_option_list)))
 		size += tcp_extopt_prepare(skb, 0, MAX_TCP_OPTION_SPACE - size,
 					   opts, tcp_to_sk(tp));
-- 
2.16.1
```