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7 min readPerfect Forward Secrecy (PFS) is a cryptographic property that ensures confidentiality of data exchanged over a network, even if the long-term encryption keys used to encrypt the data are compromised in the future. It provides an additional layer of security by preventing an attacker from retroactively decrypting past communications if they gain access to the private keys.
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5 min readTo check the size of a file in Bash, you can use the stat command in combination with the file path.Here is an example of how you can do it:Open your terminal or command prompt.Type the following command: stat --printf="%s" /path/to/file Replace /path/to/file with the actual path of the file you want to check. Press Enter.The stat command retrieves information about files in Linux and provides various data formats.
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8 min readIn Kotlin, converting a string to an entity is typically achieved using some form of parsing or deserialization. Here's a way to convert a string to an entity in Kotlin:Define the entity class: Create a data class or a regular class that represents the structure of your entity. This class should have properties that match the data fields you expect to extract from the string.
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8 min readTo check SSL/TLS vulnerabilities in a web application, follow these steps:Start by ensuring you have a reliable SSL/TLS certificate installed on the server hosting the web application. A valid certificate is essential for establishing secure communications. Check for the supported SSL/TLS versions. Disable older SSL versions such as SSLv2 and SSLv3, as they are considered weak and vulnerable to attacks. Ensure that the web server is configured to use more secure protocols like TLS 1.2 or higher.
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5 min readThe sed command, short for stream editor, is a powerful tool for performing string manipulation and text transformations in the Bash shell. It operates on a line-by-line basis and allows you to find and replace text, delete lines, insert or append text, and perform other modifications to input streams.To use sed for string manipulation in Bash, you typically provide it with a pattern and an action to be performed on that pattern.
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8 min readConfiguring a wildcard SSL certificate involves the following steps:Purchase the certificate: Begin by acquiring a wildcard SSL certificate from a reliable Certificate Authority (CA). There are numerous CAs available, so choose based on your requirements and budget. Generate a Certificate Signing Request (CSR): The next step is to generate a CSR using your server software.
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5 min readThe "awk" command is a powerful tool used for text processing in the Bash shell. It is designed for scanning and processing text files, extracting data, and performing actions based on patterns. Here is an overview of how to use the "awk" command:Basic Syntax: The basic syntax of the "awk" command is as follows: awk '/pattern/ { action }' file.
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4 min readTo generate a 10-ms timer in Kotlin, you can use the Timer class provided by the Java standard library. Here's an example of how you can achieve this:Import the necessary libraries: import java.util.Timer import java.util.TimerTask Create a Timer object and a TimerTask object: val timer = Timer() val task = object : TimerTask() { override fun run() { // Code to be executed every 10 ms goes here } } Schedule the task to run repeatedly with a delay of 10 ms: timer.
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10 min readMutual TLS (mTLS) authentication is a method used to establish secure communication between a client and a server. Unlike traditional TLS authentication, where only the server is verified by the client, mTLS authentication requires both parties to authenticate each other using digital certificates.
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4 min readTo schedule tasks with cron in Bash, you can use the following steps:Open the crontab file using the command crontab -e. This will open the file in the default editor.Each line in the crontab file represents a task you want to schedule. Each task follows a specific syntax: Minute (0-59) Hour (0-23) Day of the month (1-31) Month (1-12) Day of the week (0-7, where both 0 and 7 represent Sunday) Command to be executed Choose the values for each field based on your desired schedule.
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9 min readRecursive type checking in Kotlin refers to the process of verifying and enforcing type safety in a situation where a class or interface is defined in terms of itself. This allows the creation of complex data structures or relationships that rely on recursive definitions.When checking the types of recursive declarations in Kotlin, the compiler employs a two-step process. First, it checks the base case(s) or terminal condition(s) that break the recursion.