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pwauth(8) [centos man page]

PWAUTH(8)						      System Manager's Manual							 PWAUTH(8)

pwauth - authenticator for mod_authnz_external and the Apache HTTP Daemon SYNOPSIS
Pwauth is an authenticator designed to be used with mod_auth_external or mod_authnz_external and the Apache HTTP Daemon to support reason- ably secure web authentication out of the system password database on most versions of Unix. Particulary - secure authentication against PAM. The simplest test pwauth is to start a root shell and just run pwauth. It will attempt to read the login and password from standard input, so type a login name, hit return, then type a password, and hit return (the password will echo on your screen). The check the status code that was returned (in csh: "echo $status" in sh: "echo $?"). If the login/password were correct you should get a zero status code. If not, you will get some other value. See below the list of status codes to find the meaning of the various values returned. Any values 50 or greater indicate a configuration error. STATUS CODES
0 STATUS_OK Login OK. 1 STATUS_UNKNOWN Nonexistant login or (for some configurations) incorrect password. 2 STATUS_INVALID Incorrect password (for some configurations). 3 STATUS_BLOCKED Uid number is below MIN_UNIX_UID value configured in config.h. 4 STATUS_EXPIRED Login ID has expired. 5 STATUS_PW_EXPIRED Login's password has expired. 6 SSTATUS_NOLOGIN Logins to system have been turned off (usually by /etc/nologin file). 7 STATUS_MANYFAILES Limit on number of bad logins exceeded. 50 STATUS_INT_USER pwauth was invoked by a uid not on the SERVER_UIDS list. If you get this error code, you probably have SERVER_UIDS set incorrectly in pwauth's config.h file. 51 STATUS_INT_ARGS pwauth was not given a login & password to check. The means the passing of data from mod_auth_external to pwauth is messed up. Most likely one is trying to pass data via environment variables, while the other is trying to pass data via a pipe. 52 STATUS_INT_ERR one of several rare and unlikely internal errors occurred. You'll have to read the source code to figure these out. 53 STATUS_INT_NOROOT pwauth was not able to read the password database. Usually this means it is not running as root. (PAM and login.conf configurations will return 1 in this case.) AUTHOR
pwauth was written by Jan Wolter <>. This manual page was written by Hai Zaar <>, for the Debian project (but may be used by others). 2009-05-02 PWAUTH(8)

Check Out this Related Man Page

authenticate_user(3x)													     authenticate_user(3x)

       authenticate_user - authenticate user

       #include <pwd.h>
       #include <auth.h>   /* For error codes */

       int authenticate_user(user, password, line)
       struct passwd *user;
       char *password;
       char *line;

       user    The UID.

	       The password for the UID.

       line    The name of the login line as it is listed in

       The  routine  authenticates a username/UID against a supplied password and returns a nonnegative integer on success.  The value returned is
       the number of failed login authentication attempts since the last successful login authentication (or zero if this feature is not enabled).
       This routine is found in the library and loaded using the -lauth option.

       At all security levels higher than BSD, the login fail count in the auth database is incremented if authentication fails, and cleared if it
       succeeds.  In addition, the account must be marked enabled for logins as defined by the Account Mask value for A_LOGIN.	See  for  informa-
       tion about the Account Mask values.

       If  a  non-NULL	value is supplied for the argument and the argument is not the empty string, the function also verifies that the specified
       user is allowed access through that line. In particular, accounts with UID equal to zero will only return success if the specified line	is
       marked secure in the file.

       The process must have read access to the auth database to authenticate users in a secure environment.

       The process must have read/write access to the auth database to update the authentication fail count.

       If auth information is being served through BIND, the process is required to obtain a Kerberos ticket for that service before invoking this

       extern int errno;
       struct passwd *pwd;
       int status;

       pwd = getpwnam("root");
       status = authenticate_user(pwd, "rootpass", "/dev/console");
       if(status < 0)
	    if(errno == EPERM)
		 puts("Login failed");
	    if(status > 0)
		 printf("%d failed attempts
", status);

Return Values
       When successful, the routine returns the number of failed login authentication attempts since last successful login authentication.

       When an error occurs, is set and a negative error code is returned. The error code returned may be the same as or it  may  be  an  extended
       error code defined in

       On error return may be set to one of the following values:

       [EPERM]		 Either  the  password	is  incorrect,	the  password is expired, the specified line needs to be secure and is not, or the
			 account is disabled and a login authentication is required.

       [EINVAL] 	 No authentication information for user.

       [ENOSYS] 	 Security subsystem not configured correctly.

       [EACCES] 	 Process does not have read access to the necessary information.

       On error return the return value may be the same as or, if errno is [EPERM], it may be one of the following additional values defined in

       [A_EBADPASS]	 The supplied password was incorrect.

       [A_ESOFTEXP]	 The accounts password has expired recently.

       [A_EHARDEXP]	 The accounts password expired quite some time ago.

       [A_ENOLOGIN]	 The account is not enabled.

       [A_EOPENLINE]	 The account requires a secure line and the specified line was not marked that way in

       If the system is operating in the BSD security level, the password expiration, login fail count, and account  disabling	features  are  not
       available (and therefore are not used in authentication computations).

See Also
       getauthuid(3), getpwent(3), auth(5), passwd(5yp), ttys(5)

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