Book Image

Security with Go

By : John Daniel Leon
Book Image

Security with Go

By: John Daniel Leon

Overview of this book

Go is becoming more and more popular as a language for security experts. Its wide use in server and cloud environments, its speed and ease of use, and its evident capabilities for data analysis, have made it a prime choice for developers who need to think about security. Security with Go is the first Golang security book, and it is useful for both blue team and red team applications. With this book, you will learn how to write secure software, monitor your systems, secure your data, attack systems, and extract information. Defensive topics include cryptography, forensics, packet capturing, and building secure web applications. Offensive topics include brute force, port scanning, packet injection, web scraping, social engineering, and post exploitation techniques.
Table of Contents (15 chapters)

Decoding packet layers

Packets can be decoded layer by layer with the packet.Layer() function. This program will inspect the packets, look for TCP traffic, and then output the Ethernet layer, IP layer, TCP layer, and application layer information. This is useful when you need to inspect the traffic and make a decision based on the information. When it gets to the application layer, it looks for the HTTP keyword and prints a message if one is detected:

package main

import (
"fmt"
"github.com/google/gopacket"
"github.com/google/gopacket/layers"
"github.com/google/gopacket/pcap"
"log"
"strings"
"time"
)

var (
device = "eth0"
snapshotLen int32 = 1024
promiscuous = false
err error
timeout = 30 * time.Second
handle *pcap.Handle
)

func main() {
// Open...