Port Scanning Port Scanning searches for open ports on a remote system. The basic logic for a portscanner would be to connect to the port we want to check. If the socket gives a valid connection without any error then the port is open , closed otherwise (or inaccessible, or filtered). TCP Port Scanning Drawbacks… Read More »
DNS Query When we type a web url or domain in our browser a dns request is immediately send by our browser to a DNS server to get the IP address of that web address. In winsock applications we achieve this by gethostbyname() and things are pretty simple. In this article we shall do this… Read More »
Winsock packet sniffer A packet sniffer is a program that can sniff the packets moving on the network. All applications communicate over the network with data packets where each packet contains part of the whole data being exchanged. A sniffer is able to pickup these individual packets and read them. In this post we are… Read More »
Raw sockets using winsock Raw sockets or “Raw Packets”, enable a program to access the entire contents of a packet or datagram, both for reading and writing purpose. In other words, you can fabricate a whole packet according to your likes and dislikes. For example, a TCP packet would contain an IP header, a TCP… Read More »
Permutations Permutations is the set of all different unique arrangements of the letters of the string. So for the string “ABC” there are 6 permutations – ABC, ACB, BAC, BCA, CAB, CBA. The permutations can also be taken on a smaller length. For example if we want to get permutations of ABC over only 2… Read More »