On 06/26/2015 03:21 PM, Flavien Lebarbe wrote:
Thomas Portmann ecrivait :
I am in the process of troubleshooting another problem and noticed a
rather strange behavior with the openssh client. A client (OpenSSH
5.3) and a server (6.7p1) do the TCP handshake, the client announces
a MSS of 1460 (its MTU is 1500), while the server announces a MSS of
1260 (its MTU is set to 1300). What troubles me is, that the client
is sending the server a frame of 2034 bytes (TCP segment length of
1968, during the "Client: Key Exchange Init"). Why is it that the
client seems to ignore the servers MSS?
From what you say, the client not only disregards the server MSS, but
also the client MSS itself : 2034 is larger than 1500. That's weird...
Do you have a pcap capture of it ? Where do you see the 2034 ? In a
strace by chance ?
I have a tcpdump I made on the client. Since it is rather small (~7KB),
I will just attach it to the mail. The 2034 is taken from the capture.
tom
_______________________________________________
openssh-unix-dev mailing list
openssh-unix-dev@xxxxxxxxxxx
https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev
