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‫In Linux systems, the ETSI Shadow file stores actual passwords in encrypted format, more like the

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‫hash of the password for users account with additional properties related to the user password.

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‫Basically, it stores secure user account information.

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‫All fields are separated by colon symbol.

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‫And it contains one entry per line for each user listed in the Etsy password file.

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‫Generally, shadow file entry looks as seen in the slide.

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‫So let's see the fields of a typical Linux hash values most probably gathered from the shadow file.

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‫Just like in windows, local hashes, fields are separated by colons in the Linux hashes.

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‫The first field is username, your log, your name, the second field is your encrypted password.

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‫Usually, the password format is set to dollar ID $ $80 hash.

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‫The ID is the algorithm used on going to Linux as follows.

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‫Dollar one dollar is MD5.

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‫Dollar to a dollar is blowfish.

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‫Dollar to why dollar is blowfish.

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‫Dollar five S. Dollar is a 256 dollar, $6, is 512.

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‫Now, the third field is the date that the password was last modified.

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‫The fourth field is the minimum number of days required between password changes.

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‫That is, the number of days left before the user is allowed to change his or her password.

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‫The fifth field is the maximum number of days a password is valid.

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‫After that, the user is forced to change his or her password.

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‫The sixth field is the number of days before the password is to expire, that user is warned that his

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‫or her password must be changed.

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‫Now there are two more fields in the line which are blank in this example.

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‫The seventh field is called inactive, which is the number of days after password expires that the account

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‫is disabled.

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‫And the last field is called expire, which indicates the days since one January 1970 that the account

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‫is disabled.

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‫That is an absolute date, specifying when the log in may no longer be used.