----- Original Message ----- From: "soulstone" <[email protected]> To: <[email protected]> Sent: Friday, December 04, 2009 7:02 AM Subject: Re: [Winpcap-users] Monitoring multiple network interfaces
> Gianluca Varenni wrote: >> ----- Original Message ----- >> From: "soulstone" <[email protected]> >> To: <[email protected]> >> Sent: Thursday, December 03, 2009 8:49 AM >> Subject: [Winpcap-users] Monitoring multiple network interfaces >> >> >>> Hi, >>> >>> I've tried to monitor multiple networ interfaces installed on >>> a system. >>> The reason is that I need to monitor network traffic to determine >>> whether a user navigates to a given url. >>> >>> I'd rather capture only packages from the interface which is connected >>> to the internet but I don't know how to find out which one I need. >>> >>> So I tried to monitor all interfaces. >>> I did this by creating one thread per interface which calls pcap_loop. >>> But this doesn't work. >> >> What do you mean by "it doesn't work"? > > 1. I use pcap_findalldevs to get all devices. > 2. I open every interface by pcap_open_live. > 3. I use a loop to itter through all interfaces and spawn > a seperated thread for each call of pcap_loop(Desc, 0, @PacketHandler, > Err). > > Usually after that the method PacketHandler would be called > if I only invoke pcap_look for the correct interface with internet access. > But if I try to monitor multiple interfaces the function PacketHandler > isn't called anymore. > > I also tried to reverse the loop (the first interface is coincidental > the one with internet access) it works. What's the name of the interface with real traffic? What OS are you running on? GV > > Example code: > // doesn't work > for i := 0 to Length(Interfaces) - 1 do > begin > // creates a thread which calls pcap_loop > SpawnMonitor(Interfaces[i]; > end; > > // works, because our (now last) item is the correct NIC > for i := Length(ValidP) - 1 downto 0 do > begin > SpawnMonitor(Interfaces[i]; > end; > > So the problem is that PacketHandler isn't called for all devices. > > Kind regards, > dy > >> >> GV >> >>> Specifying only one interface everything works fine. >>> Can I only monitor one interface at once or do I miss something? >>> >>> Maybe someone can give me an advice. >>> >>> >>> Kind regards, >>> dy >>> _______________________________________________ >>> Winpcap-users mailing list >>> [email protected] >>> https://www.winpcap.org/mailman/listinfo/winpcap-users >> _______________________________________________ >> Winpcap-users mailing list >> [email protected] >> https://www.winpcap.org/mailman/listinfo/winpcap-users >> > _______________________________________________ > Winpcap-users mailing list > [email protected] > https://www.winpcap.org/mailman/listinfo/winpcap-users _______________________________________________ Winpcap-users mailing list [email protected] https://www.winpcap.org/mailman/listinfo/winpcap-users
