How to save the packages received by a network interface or some port in a file and resend the packages received when needed?
hi, This is a question not specific to Python,but its related somehow,and I believe I can get some help from your fellow:) I am doing my work on a server service program on Linux that processes the packages sent to the socket it listens.Their is already a old such service listening on the port doing its job,and I can't stop the old server service, and I need to get the packages sent to the old server and send them to my new server service to make sure it works well .How can I get the package and resent them to my new service? Is there such a tool or is there some functionality that tools such as tcpdump already provides? Thanks:) -- http://mail.python.org/mailman/listinfo/python-list
Re: How to save the packages received by a network interface or some port in a file and resend the packages received when needed?
Its possible using TCPDUMP and wireshark. however its a bit of a manual process (open the pcap in wireshark, select the correct tcp stream, and extract the file). I did this to show a vulnerability in how medical images were transmitted in a university hospital once :) Here are some guides, maybe it can serve as a jumping off point? http://packetlife.net/blog/2009/jul/13/quick-packet-capture-data-extraction/ http://wiki.wireshark.org/TCP_Reassembly There are some C# libraries specifically for this: http://www.codeproject.com/KB/IP/TcpRecon.aspx Not sure if anything exists explicitly for python though. -Matty On Wed, Aug 31, 2011 at 9:35 AM, king6c...@gmail.com king6c...@gmail.com wrote: hi, This is a question not specific to Python,but its related somehow,and I believe I can get some help from your fellow:) I am doing my work on a server service program on Linux that processes the packages sent to the socket it listens.Their is already a old such service listening on the port doing its job,and I can't stop the old server service, and I need to get the packages sent to the old server and send them to my new server service to make sure it works well .How can I get the package and resent them to my new service? Is there such a tool or is there some functionality that tools such as tcpdump already provides? Thanks:) -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: How to save the packages received by a network interface or some port in a file and resend the packages received when needed?
On 2011-08-31, Matty Sarro msa...@gmail.com wrote: Its possible using TCPDUMP and wireshark. however its a bit of a manual process (open the pcap in wireshark, select the correct tcp stream, and extract the file). Presumably the OP knows the port IP address and port number on which the server is listening, so wouldn't it be simpler to just capture TCP traffic to/from that IP/port? Then you can play it back using tcprewrite, tcpreplay, et al. But, I don't see how that's going to work. The OP seems to want to capture a TCP session and then replay it so that the client from the session ends up talking to a different server during the replay. The chances of the new server starting up a connection with the same ACK sequence number is practially nil isn't it? ?? This is a question not specific to Python,but its related somehow,and I believe I can get some help from your fellow:) ?? I am doing my work on a server service program on Linux that processes the packages sent to the socket it listens.Their is already a old such service listening on the port doing its job,and I can't stop the old server service, and I need to get the packages sent to the old server and send them to my new server service to make sure it works well .How can I get the package and resent them to my new service? Is there such a tool or is there some functionality that tools such as tcpdump already provides? Thanks:) -- Grant Edwards grant.b.edwardsYow! ... this must be what at it's like to be a COLLEGE gmail.comGRADUATE!! -- http://mail.python.org/mailman/listinfo/python-list
Re: How to save the packages received by a network interface or some port in a file and resend the packages received when needed?
On 8/31/2011 6:35 AM king6c...@gmail.com said... hi, This is a question not specific to Python,but its related somehow,and I believe I can get some help from your fellow:) I am doing my work on a server service program on Linux that processes the packages sent to the socket it listens.Their is already a old such service listening on the port doing its job,and I can't stop the old server service, and I need to get the packages sent to the old server and send them to my new server service to make sure it works well .How can I get the package and resent them to my new service? Is there such a tool or is there some functionality that tools such as tcpdump already provides? I recently set up a standby spare fax server on a network that I also needed to test, and was able to tee the source transmissions to both systems. That may be an option, particularly as it sounds like you've written a consumer of info and are not replying and interacting with the source. Emile -- http://mail.python.org/mailman/listinfo/python-list
Re: How to save the packages received by a network interface or some port in a file and resend the packages received when needed?
In fact,UDP is enough for me,I heared that tcpdump and netcat can store and resend the udp packages to get the replay effect,but I don't know how, or is there some better way? I am working on a Linux server and only some basic terminal tools are available :) 2011/8/31 Emile van Sebille em...@fenx.com On 8/31/2011 6:35 AM king6c...@gmail.com said... hi, This is a question not specific to Python,but its related somehow,and I believe I can get some help from your fellow:) I am doing my work on a server service program on Linux that processes the packages sent to the socket it listens.Their is already a old such service listening on the port doing its job,and I can't stop the old server service, and I need to get the packages sent to the old server and send them to my new server service to make sure it works well .How can I get the package and resent them to my new service? Is there such a tool or is there some functionality that tools such as tcpdump already provides? I recently set up a standby spare fax server on a network that I also needed to test, and was able to tee the source transmissions to both systems. That may be an option, particularly as it sounds like you've written a consumer of info and are not replying and interacting with the source. Emile -- http://mail.python.org/**mailman/listinfo/python-listhttp://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: How to save the packages received by a network interface or some port in a file and resend the packages received when needed?
On 8/31/2011 8:37 AM king6c...@gmail.com said... In fact,UDP is enough for me,I heared that tcpdump and netcat can store and resend the udp packages to get the replay effect,but I don't know how, That may be, but I've never tried that. or is there some better way? I am working on a Linux server and only some basic terminal tools are available :) If appropriate, I'd try the iptables --tee option. Emile -- http://mail.python.org/mailman/listinfo/python-list
