Linux, Windows, Security, Programming, Network Tutorials
Authentication is important part of the operations systems like Linux. As Linux operating systems are multi user systems and runs a lot of services and complex scenarios they generally need robust and easy to implement complex scenarios authentication system. Linux Pluggable Authentication a.k.a. Linux PAM is very robust and dynamic authentication system. In this tutorial we will try to explain
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SSH protocol provides different ways for authentication. Key based authentication is the most secure one. In order to use key based authentication we should store the key in a command place. SSH agents reads keys and uses for authentication with remote system. We can use ssh-add to store keys in a common path. Key Files Public and private keys are store
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ddrescue is a GNU provided data recovery tool.It can copy and recover file, directory or whole hard drive. The best part of the ddrescue is it can prevent or solve read errors. Install For Ubuntu, Debian, Kali and Mint We can install ddrescue tool for deb based distributions like below. ddrescue command is provided with package name gddrescue.
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$ sudo apt install gddrescue |
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User PC and Servers process a lot of data where some of them are secret. This data may be deleted with conventional ways but this may not enough. Because file systems generally removes file metadata but continue to hold real data. Microsoft sysinternals provides sdelete or secure delete tool which can delete file data really. More information about sysinternals can
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OpenSSL provides read different type of certificate and encoding formats. OpenSSL supports certificate formats like RSA, X509, PCKS12 etc. We will look how to read these certificate formats with OpenSSL. Read RSA Private Key RSA is popular format use to create asymmetric key pairs those named public and private key. We can use rsa verb to read RSA private key with
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OpenSSL provides cryptographic libraries and features. We can use OpenSSL from reading DER files to generate random numbers. But one of the most used feature is creating a Self Signed Certificate. , Self Signed Certificate X509 is the certificate standard used in internet and corporate today. X509 certificates are designed to create a tree like trust hierarchy between X509 certificates.
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DER and PEM are formats used in X509 and other certificates to store Public , Private Keys and other related information. OpenSSL provides a lot of features for manipulating PEM and DER certificates. We can use OpenSSL to convert DER to PEM format and vice versa. Convert DER Format To PEM Format For RSA Key We may have a RSA
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OpenSSL is very long running project which have passed a lot of versions. Newer versions provides more features, bug fixes and security patches. For example in year 2014 a serious security hole Heart Bleed discovered in OpenSSL versions and affected OpenSSL libraries are defined as versions.Following versions was vulnerable to Hear Bleed. OpenSSL 1.0.1 trough 1.0.1f inclusive OpenSSL 1.0.1g is
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OpenSSL provides different features about security and certificates. Public and Private Key cryptography also supported by OpenSSL. Websites, Firewalls and other applications uses Certificates in order to encrypt their network traffic or authenticate each other. In this tutorial we will look how to create Certificate Signing Request. Generate RSA Key Now we assume we do not have any Public and
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OpenSSL is great library and tool set used in security related work. While talking security we can not deny that passwords and random numbers are important subjects. In this tutorial we will learn how to generate random numbers and passwords with OpenSSL. Generate Base64 Random Numbers Base64 is an encoding format used in applications and different systems which can be
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