[Winpcap-users] Access violation when using pcap_findalldevs_ex

[Виталик Rasta]

Hello, everyone!

I have an access violation error when using pcap_findalldevs_ex. I use
Microsoft
Visual studio 2005 and winpcap 4.0.2 on WinXP Professional SP2.

There are no errors when I use pcap_finalldevs_ex in other functions.
Error occurs just in send_packet function.

I don't understand where is the mistake. Please, help me!

I know exactly that error is when pcap_findalldevs_ex runs (I  used
F10, F11)

here is the code:
bool send_packet(u_char *data, int size)
{
        pcap_if_t *alldev=NULL;
        pcap_if_t *dev;

        pcap_t *handle;

        char errbuf[PCAP_ERRBUF_SIZE];

        if (pcap_findalldevs_ex(PCAP_SRC_IF_STRING, NULL, &alldev, errbuf)
== -1) {

                std::cout << "Cannot get interface list : " << errbuf <<
"\n";

                return false;
        }

        dev = alldev->next;

        if (dev == NULL) {

                std::cout << "Cannot find an interface \n";
                pcap_freealldevs(alldev);

                return false;
        }

        handle = pcap_open(dev->name, PCAP_PACKET_PORTION,
PCAP_OPENFLAG_PROMISCUOUS, PCAP_READ_TIMEOUT, NULL, errbuf);

        if (handle == NULL) {

                std::cout << "Cannot open an interface : " << errbuf << "\n";
                pcap_freealldevs(alldev);

                return false;
        }

        if (pcap_datalink(handle) != DLT_EN10MB) {

                std::cout << "This program works only on Ethernet
networks\n";

                pcap_freealldevs(alldev);

                return false;
        }

        if (pcap_sendpacket(handle, data, size) != 0) {

                std::cout << "Error sending packet : " <<
pcap_geterr(handle) << "\n";
                pcap_freealldevs(alldev);

                return false;

        }

        pcap_freealldevs(alldev);

        return true;
}


-- 
Best wishes!
Vitaly                       mailto:johanga at sibmail.com