This article describes /Etc/Passwd File Format In Linux

Just like Windows, iOS, and Mac OS, Linux is an operating system. In fact, one of the most popular platforms on the planet, Android, is powered by the Linux operating system. An operating system is software that manages all of the hardware resources associated with your desktop or laptop. To put it simply, the operating system manages the communication between your software and your hardware. Without the operating system (OS), the software wouldn?t function.

Linux is the best-known and most-used open source operating system. As an operating system, Linux is software that sits underneath all of the other software on a computer, receiving requests from those programs and relaying these requests to the computer’s hardware.

For the purposes of this page, we use the term “Linux” to refer to the Linux kernel, but also the set of programs, tools, and services that are typically bundled together with the Linux kernel to provide all of the necessary components of a fully functional operating system. Some people, particularly members of the Free Software Foundation, refer to this collection as GNU/Linux, because many of the tools included are GNU components. However, not all Linux installations use GNU components as a part of their operating system. Android, for example, uses a Linux kernel but relies very little on GNU tools.

Every version of the Linux operating system manages hardware resources, launches and handles applications, and provides some form of user interface. The enormous development community and wide range of distributions means that a Linux version is available for almost any task, and Linux has penetrated many areas of computing.

/etc/passwd is a text file that contains the attributes of (i.e., basic information about) each user or account on a computer running Linux or another Unix-like operating system.

The permissions for /etc/passwd are by default set so that it is world readable, that is, so that it can be read by any user on the system1. The file can be easily read using a text editor (such as gedit or vi) or with a command such as cat, which is commonly used to read files, i.e.,

/etc/passwd file stores essential information, which is required during login i.e. user account information. /etc/passwd is a text file, which contains a list of the system’s accounts, giving for each account some useful information like user ID, group ID, home directory, shell, etc. It should have general read permission as many utilities like ls use it to map user IDs to user names, but write access only for the superuser/root account.

passwd is a tool on most Unix and Unix-like operating systems used to change a user's password. The password entered by the user is run through a key derivation function to create a hashed version of the new password, which is saved. Only the hashed version is stored; the entered password is not saved for security reasons.

When the user logs on, the password entered by the user during the log on process is run through the same key derivation function and the resulting hashed version is compared with the saved version. If the hashes are identical, the entered password is considered to be correct, and the user is authenticated. In theory, it is possible for two different passwords to produce the same hash. However, cryptographic hash functions are designed in such a way that finding any password that produces the same hash is very difficult and practically infeasible, so if the produced hash matches the stored one, the user can be authenticated.

Now you can find some examples in this video.

Please subscribe to support our channel.
To be aware of our new videos please subscribe our channel.

Visit our website https://sdk-it.com
Visit our youtube channel
Watch IT & Learn IT & Apply IT.

Enjoy!