Forgot your password?
New user?
The Ticket-Granting Ticket
Document Actions
How User Information is Stored on Your System
How User Information is Stored on Your System
Next: PAM Pluggable Authentication Modules Up: Linux Authentication Systems Previous: Contents
How User Information is Stored on Your System
- /etc/passwd
On almost all linux distributions (and commercial *nixes as well), user information is stored in /etc/passwd, a text file which contains the user's login, their encrypted password, a unique numerical user id (called the uid), a numerical group id (called the gid), an optional comment field (usually containing such items as their real name, phone number, etc.), their home directory, and their preferred shell. A typical entry in /etc/passwd looks something like this:
bozo:$1$SJurthXL$mqa.kXhYQSLFm/CUX0BaE:1000:1000:Bozo the Clown:/home/bozo:/bin/bashWhat follows is a discussion of various authentication and authorization methods. This isn't as simple as simply choosing one. Several can interact with each other, for example:
- SASL can use pam to determine what authorizations are allowed for a given user
- LDAP can use SASL as the authentication mechanism
- SASL can use kerberos tokens for authentication and authorization
- passwords for SASL can be looked up from an LDAP server
- PAM can use ldap for storing usernames and passord authentication information
Next: PAM Pluggable Authentication Modules Up: Linux Authentication Systems Previous: Contents
2005-05-04