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pam_unix(8) [netbsd man page]

PAM_UNIX(8)						    BSD System Manager's Manual 					       PAM_UNIX(8)

NAME
pam_unix -- UNIX PAM module SYNOPSIS
[service-name] module-type control-flag pam_unix [options] DESCRIPTION
The UNIX authentication service module for PAM provides functionality for two PAM categories: authentication and account management. In terms of the module-type parameter, they are the ``auth'' and ``account'' features. It also provides a null function for session management. UNIX Authentication Module The UNIX authentication component provides functions to verify the identity of a user (pam_sm_authenticate()), which obtains the relevant passwd(5) entry. It prompts the user for a password and verifies that this is correct with crypt(3). The following options may be passed to the authentication module: debug syslog(3) debugging information at LOG_DEBUG level. use_first_pass If the authentication module is not the first in the stack, and a previous module obtained the user's password, that password is used to authenticate the user. If this fails, the authentication module returns failure without prompting the user for a password. This option has no effect if the authentication module is the first in the stack, or if no previous modules obtained the user's password. try_first_pass This option is similar to the use_first_pass option, except that if the previously obtained password fails, the user is prompted for another password. auth_as_self This option will require the user to authenticate himself as the user given by getlogin(2), not as the account they are attempting to access. This is primarily for services like su(1), where the user's ability to retype their own password might be deemed sufficient. nullok If the password database has no password for the entity being authenticated, then this option will forgo password prompting, and silently allow authentication to succeed. UNIX Account Management Module The UNIX account management component provides a function to perform account management, pam_sm_acct_mgmt(). The function verifies that the authenticated user is allowed to login to the local user account by checking the password expiry date. The following options may be passed to the management module: debug syslog(3) debugging information at LOG_DEBUG level. UNIX Password Management Module The UNIX password management component provides a function to perform account management, pam_sm_chauthtok(). The function changes the user's password. The following options may be passed to the password module: debug syslog(3) debugging information at LOG_DEBUG level. no_warn suppress warning messages to the user. These messages include reasons why the user's authentication attempt was declined. passwd_db=name Change the user's password only the specified password database. Valid password database names are: files local password file nis NIS password database FILES
/etc/master.passwd default UNIX password database. SEE ALSO
passwd(1), getlogin(2), crypt(3), getpwent(3), syslog(3), nsswitch.conf(5), passwd(5), nis(8), pam(8) BSD
February 26, 2005 BSD

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PAM_KRB5(8)						    BSD System Manager's Manual 					       PAM_KRB5(8)

NAME
pam_krb5 -- Kerberos 5 PAM module SYNOPSIS
[service-name] function-class control-flag pam_krb5 [options] DESCRIPTION
The Kerberos 5 PAM module supports the authentication, account management and password management function classes. In terms of the function-class parameter, these are ``auth'' , ``account'' and ``password'' respectively. Kerberos 5 Authentication Module The Kerberos 5 authentication component provides functions to verify the identity of a user (pam_sm_authenticate()) and to set user specific credentials (pam_sm_setcred()). pam_sm_authenticate() converts the supplied username into a Kerberos principal, by appending the default local realm name. It also supports usernames with explicit realm names. If a realm name is supplied, then upon a successful return, it changes the username by mapping the principal name into a local username (calling krb5_aname_to_localname()). This typically just means the realm name is stripped. It prompts the user for a password and obtains a new Kerberos TGT for the principal. The TGT is verified by obtaining a service ticket for the local host. When prompting for the current password, the authentication module will use the prompt ``Password for <principal>:''. The pam_sm_setcred() function stores the newly acquired credentials in a credentials cache, and sets the environment variable KRB5CCNAME appropriately. The credentials cache should be destroyed by the user at logout with kdestroy(1). The following options may be passed to this authentication module: debug openpam_log(3) debugging information at PAM_LOG_DEBUG level. use_first_pass If the authentication module is not the first in the stack, and a previous module obtained the user's password, that pass- word is used to authenticate the user. If this fails, the authentication module returns failure without prompting the user for a password. This option has no effect if the authentication module is the first in the stack, or if no previous modules obtained the user's password. try_first_pass This option is similar to the use_first_pass option, except that if the previously obtained password fails, the user is prompted for another password. forwardable Obtain forwardable Kerberos credentials for the user. no_ccache Do not save the obtained credentials in a credentials cache. This is a useful option if the authentication module is used for services such as ftp or pop, where the user would not be able to destroy them. [This is not a recommendation to use the module for those services.] ccache=name Use name as the credentials cache. name must be in the form type:residual. The special tokens '%u', to designate the decimal UID of the user; and '%p', to designate the current process ID; can be used in name. default_principal Construct the principal from the authenticating user's username, rather than obtaining it from the AuthenticationAuthority of the user's OpenDirectory record. use_kcminit Don't verify password, instead store the password in kcm and return success in the pam chain. So when used in this mode, the pam_krb5 module needs to be configured to be 'optional' and some other module 'required'. Kerberos 5 Account Management Module The Kerberos 5 account management component provides a function to perform account management, pam_sm_acct_mgmt(). The function verifies that the authenticated principal is allowed to login to the local user account by calling krb5_kuserok() (which checks the user's .k5login file). Kerberos 5 Password Management Module The Kerberos 5 password management component provides a function to change passwords (pam_sm_chauthtok()). The username supplied (the user running the passwd(1) command, or the username given as an argument) is mapped into a Kerberos principal name, using the same technique as in the authentication module. Note that if a realm name was explicitly supplied during authentication, but not during a password change, the mapping done by the password management module may not result in the same principal as was used for authentication. Unlike when changing a UNIX password, the password management module will allow any user to change any principal's password (if the user knows the principal's old password, of course). Also unlike UNIX, root is always prompted for the principal's old password. The password management module uses the same heuristics as kpasswd(1) to determine how to contact the Kerberos password server. The following options may be passed to this password management module: debug syslog(3) debugging information at LOG_DEBUG level. use_first_pass If the password management module is not the first in the stack, and a previous module obtained the user's old password, that password is used to authenticate the user. If this fails, the password management module returns failure without prompting the user for the old password. If successful, the new password entered to the previous module is also used as the new Ker- beros password. If the new password fails, the password management module returns failure without prompting the user for a new password. try_first_pass This option is similar to the use_first_pass option, except that if the previously obtained old or new passwords fail, the user is prompted for them. ENVIRONMENT
KRB5CCNAME Location of the credentials cache. FILES
/tmp/krb5cc_uid default credentials cache (uid is the decimal UID of the user). $HOME/.k5login file containing Kerberos principals that are allowed access. SEE ALSO
kdestroy(1), passwd(1), syslog(3), pam.conf(5), DirectoryService(8), pam(8) NOTES
Applications should not call pam_authenticate() more than once between calls to pam_start() and pam_end() when using the Kerberos 5 PAM mod- ule. BSD
January 15, 1999 BSD
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