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visits member for 2 years, 4 months
seen Oct 24 '12 at 10:54

Jul
28
awarded  Commentator
Jul
28
comment Is my TCP connections sabotaged by my country's government?
Nah! We are on the wrong track. this is the pcap file I captured from connecting to kernel.org: uploadmb.com/dw.php?id=1343452091 . The tcp checksum is incorrect here, too but the connection doesn't fail. kernel.org is the only non-Iranian website that I can make a tcp connection on port 443 that I am aware of.
Jul
28
comment Is my TCP connections sabotaged by my country's government?
@pQd: You are right. Apparently my network adapter doesn't support rx offloading off. but I turned off every thing else with ethtool -K and here is the result: uploadmb.com/dw.php?id=1343450959 . Exactly the same. the strange thing is the sending packets from my side have wrong tcp checksum not the received ones. I tried it on other computers in our network but the results didn't change. could it be a miss configuration in our network?
Jul
26
awarded  Nice Question
Jul
25
comment Is my TCP connections sabotaged by my country's government?
This problem occurs at my workplace. I am going home now! So I might answer the comments with delay, if any... Tomorrow is a holiday but fortunately I have ssh access to my workplace from home (if the internet is not broken there!)
Jul
25
comment Is my TCP connections sabotaged by my country's government?
@pQd: I executed the iptables and all the chains are empty. But the ethtool says "Cannot set device rx csum settings: Operation not supported"
Jul
25
comment Is my TCP connections sabotaged by my country's government?
Thank you. I couldn't find any problem with the ACK packet myself too. But the thing is that this problem happens every day (from 4 days ago) at morning in my workplace! Every body (about 50 person) have exactly the same problem and I still wonder why? I don't have the same problem at home but I hear from my friends that Internet has serious problems these days.
Jul
25
comment Is my TCP connections sabotaged by my country's government?
My guess is that government is changing the second packet (SYN/ACK) so the packet is not valid and therefore it is never making it to the TCP stack.
Jul
25
comment Is my TCP connections sabotaged by my country's government?
No, my iptables doesn't have any rules at all and on another note I have to say I can establish TCP connection successfully to any host inside iran or even a couple of foreign web sites (only kernel.org actually!)
Jul
25
comment Is my TCP connections sabotaged by my country's government?
The problem is not SSL. It is TCP. The TCP connnection will not establish at the first place, so SSL will not even begin to send its header. it is not only 443 port number e.g I can't even start a normal http connection to a server on port 8000 and your openssl command will result in "connect: Connection timed out"
Jul
25
comment Is my TCP connections sabotaged by my country's government?
Yes. I execute tcpdump -w gmail.pcap and then telnet gmail.com 443.
Jul
25
comment Is my TCP connections sabotaged by my country's government?
I deliberately did not mention it. But now that you ask, I can't think of a reason why not to tell. This is one of my day-to-day problems in Iran.
Jul
25
awarded  Student
Jul
25
asked Is my TCP connections sabotaged by my country's government?