An introduction to Linux socket and network Application Programming Interface (API) functions. Unsigned long int INADDR_LOOPBACK You can use this macro constant to stand for the ''address of this machine'' instead of finding its actual address.It is the Internet address '127.0.0.1', which is usually called 'localhost'. This special constant saves you the trouble of looking up the address of your own machine.Also, the system usually implements INADDR_LOOPBACK specially, avoiding any network traffic for the case of one machine talking to itself. unsigned long int INADDR_ANY You can use this macro constant to stand for ''any incoming address'' when binding to an address. This is the usual address to give in the sin_addr member of struct sockaddr_in when you want your server to accept Internet connections. unsigned long int INADDR_BROADCAST This macro constant is the address you use to send a broadcast message. unsigned long int INADDR_NONE This macro constant is returned by some functions to indicate an error.
Host Address Functions - Functions to operate on them Data Type struct hostent. Hacking Techniques in Wireless Networks. Prabhaker Mateti Department of Computer Science and EngineeringWright State UniversityDayton, Ohio 45435-0001 This article is scheduled to appear in “The Handbook of Information Security”, Hossein Bidgoli (Editor-in-Chief), John Wiley & Sons, Inc., 2005. 1. Introduction. 2 2. 2.1 Stations and Access Points. 3 2.2 Channels. 4 2.4 Infrastructure and Ad Hoc Modes. 4 2.5 Frames. 4 2.6 Authentication. 5 2.7 Association. 6 3. 3.1 Passive Scanning. 7 3.2 Detection of SSID.. 8 3.3 Collecting the MAC Addresses. 8 3.4 Collecting the Frames for Cracking WEP. 8 3.5 Detection of the Sniffers. 9 4. 4.1 MAC Address Spoofing. 10 4.2 IP spoofing. 10 4.3 Frame Spoofing. 11 5. 5.1 Detection of SSID.. 12 5.2 Detection of APs and stations. 12 5.3 Detection of Probing. 12 6. 6.1 Configuration. 12 6.2 Defeating MAC Filtering. 13 6.3 Rogue AP. 13 6.4 Trojan AP. 13 6.5 Equipment Flaws. 13 7. 7.1 Jamming the Air Waves. 14 7.2 Flooding with Associations. 14 7.3 Forged Dissociation. 14 7.4 Forged Deauthentication. 15 7.5 Power Saving. 15 8.
Libpcap packet capture tutorial. Packet Sniffer Code in C using Linux Sockets (BSD) #include<netinet/in.h> #include<errno.h> #include<netdb.h> #include<stdio.h> //For standard things #include<stdlib.h> //malloc #include<string.h> //strlen #include<netinet/ip_icmp.h> //Provides declarations for icmp header #include<netinet/udp.h> //Provides declarations for udp header #include<netinet/tcp.h> //Provides declarations for tcp header #include<netinet/ip.h> //Provides declarations for ip header #include<netinet/if_ether.h> //For ETH_P_ALL #include<net/ethernet.h> //For ether_header #include<sys/socket.h> #include<arpa/inet.h> #include<sys/ioctl.h> #include<sys/time.h> #include<sys/types.h> #include<unistd.h> void ProcessPacket(unsigned char* , int); void print_ip_header(unsigned char* , int); void print_tcp_packet(unsigned char * , int ); void print_udp_packet(unsigned char * , int ); void print_icmp_packet(unsigned char* , int ); void PrintData (unsigned char* , int); FILE *logfile; struct sockaddr_in source,dest; int tcp=0,udp=0,icmp=0,others=0,igmp=0,total=0,i,j; int main() struct sockaddr saddr;
Packet Capture and Analayzer. Download source files - 364 Kb Introduction The first idea of writing a packet sniffer program came from a reply to my comments on one of the projects named "NetSend ( Sending popup messenger messages between computers )" by Marc Clifton. Marc asked me "What about receiving message". To say the truth, I didn't know how I could do that. After previewing the WinPCap source code , my first trial was to write a wrapper class for it. First I traced the packets captured by Etheral and built some protocols and was able to display them in my test program. Project contents Pacanal name comes from PACket ANALyzer.
ColumnSorter This class enables to sort list view items. Requirements To run the code you need to have those below: Windows NT / 2K / XP A PC with an Ethernet card (LOL) NDIS packet capture driver (npf.sys) installed npf.sys can be downloaded from the site which is the one I used. Warning After downloading the project files. Conclusion. Ch14 : Linux Firewalls Using iptables. Network security is a primary consideration in any decision to host a website as the threats are becoming more widespread and persistent every day.
One means of providing additional protection is to invest in a firewall. Though prices are always falling, in some cases you may be able to create a comparable unit using the Linux iptables package on an existing server for little or no additional expenditure. This chapter shows how to convert a Linux server into: A firewall while simultaneously being your home website's mail, web and DNS server. A router that will use NAT and port forwarding to both protect your home network and have another web server on your home network while sharing the public IP address of your firewall. Creating an iptables firewall script requires many steps, but with the aid of the sample tutorials, you should be able to complete a configuration relatively quickly. Before you begin, you need to make sure that the iptables software RPM is installed.
In this example: The Linux socket TCP/IP protocols network programming tutorials using open source GNU compiler with C language through working program examples and code samples on Linux client-server configuration. 20 Linux System Monitoring Tools Every SysAdmin Should Know. Need to monitor Linux server performance? Try these built-in commands and a few add-on tools.
Most Linux distributions are equipped with tons of monitoring. These tools provide metrics which can be used to get information about system activities. You can use these tools to find the possible causes of a performance problem. The commands discussed below are some of the most basic commands when it comes to system analysis and debugging server issues such as: Finding out bottlenecks.Disk (storage) bottlenecks.CPU and memory bottlenecks.Network bottlenecks. #1: top - Process Activity Command The top program provides a dynamic real-time view of a running system i.e. actual process activity. Fig.01: Linux top command Commonly Used Hot Keys The top command provides several useful hot keys: => Related: How do I Find Out Linux CPU Utilization?
#2: vmstat - System Activity, Hardware and System Information Display Memory Utilization Slabinfo # vmstat -m Get Information About Active / Inactive Memory Pages. Understanding Windows Logging. This article will focus on the importance of monitoring your windows event logs and will highlight the information that is able to be extracted from typical windows logs that help to secure your critical servers.
The importance of monitoring the logs will be stressed and creative ways to do this centrally will also be covered. Logging is a very important factor when attempting to decipher what has taken place on a server. Defending critical servers by using log information. Logging is an underused tool on most windows networks. It is mostly used in a crisis to rectify events that have already taken place and that were not preempted. This is true for several reasons firstly there is vast amounts of data to get through, and because logistically it may not be viable to inspect every log on a vast network manually, this aspect is neglected.
The Event Log service is automatically started automatically when windows machine starts. Windows has several different logs that should be monitored. Scanrand Dissected: A New Breed of Network Scanner - Research - SecureWorks. Featured Advanced Threat Protection with Dell SecureWorks This white paper defines advanced threats, reviews the types of techniques advanced threat actors use as they relate to the kill chain, recommends specific steps for an effective defense strategy and defines how Dell SecureWorks services can help organizations detect, defend and eradicate advanced threats. Dell SecureWorks is a Leader in the new Gartner Magic Quadrant for Global MSSPs Dell SecureWorks has been positioned in the Leaders quadrant of Gartner's newly released Magic Quadrant for Global MSSPs (26 February 2014).
Enterprise Best Practices for Cryptocurrency Adoption Keeping funds and transaction information secure from prying eyes is of the utmost importance when handling finances. No Financial Institution is Too Small a Target for DDoS Attacks Distributed denial-of-service (DDoS) attacks are prevalent and growing, especially in the financial services industry.
CISO's Guide to Advanced Attackers eBook.