Security

crypt()

crypt() is the C library function that turns a password and salt into the hash string stored for an account. Login programs compare its output to the stored field, so its error behavior affects security.

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What Is the Shadow Password Field? * and ! Explained

The shadow password field decides how a Linux account can authenticate. Learn what $6$, * and ! mean, and why the difference matters for SSH.

beginner 5 min read

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