1 files changed, 0 insertions, 130 deletions
diff --git a/doc/man/pam_fail_delay.3 b/doc/man/pam_fail_delay.3
deleted file mode 100644
index f6cd238a..00000000
--- a/doc/man/pam_fail_delay.3
+++ /dev/null
@@ -1,130 +0,0 @@
-.\" Hey Emacs! This file is -*- nroff -*- source.
-.\" $Id$
-.\" Copyright (c) Andrew G. Morgan 1997 <morgan@parc.power.net>
-.TH PAM_FAIL_DELAY 3 "1997 Jan 12" "Linux-PAM 0.56" "Programmers' Manual"
-.SH NAME
-
-pam_fail_delay \- request a delay on failure
-
-.SH SYNOPSIS
-.B #include <security/pam_appl.h>
-.br
-or,
-.br
-.B #include <security/pam_modules.h>
-.sp
-.BI "int pam_fail_delay(pam_handle_t " "*pamh" ", unsigned int " "usec" ");"
-.sp 2
-.SH DESCRIPTION
-.br
-It is often possible to attack an authentication scheme by exploiting
-the time it takes the scheme to deny access to an applicant user.  In
-cases of
-.I short
-timeouts, it may prove possible to attempt a
-.I brute force
-dictionary attack -- with an automated process, the attacker tries all
-possible passwords to gain access to the system.  In other cases,
-where individual failures can take measurable amounts of time
-(indicating the nature of the failure), an attacker can obtain useful
-information about the authentication process.  These latter attacks
-make use of procedural delays that constitute a
-.I covert channel
-of useful information.
-
-.br
-To minimize the effectiveness of such attacks, it is desirable to
-introduce a random delay in a failed authentication process.
-.B Linux-PAM
-provides such a facility.  The delay occurs upon failure of the
-.BR pam_authenticate "(3) "
-and
-.BR pam_chauthtok "(3) "
-functions.  It occurs
-.I after
-all authentication modules have been called, but
-.I before
-control is returned to the service application.
-
-.br
-The function,
-.BR pam_fail_delay "(3),"
-is used to specify a required minimum for the length of the
-failure-delay; the
-.I usec
-argument.  This function can be called by the service application
-and/or the authentication modules, both may have an interest in
-delaying a reapplication for service by the user.  The length of the
-delay is computed at the time it is required.  Its length is
-pseudo-gausianly distributed about the
-.I maximum
-requested value; the resultant delay will differ by as much as 25% of
-this maximum requested value (both up and down).
-
-.br
-On return from
-.BR pam_authenticate "(3) or " pam_chauthtok "(3),"
-independent of success or failure, the new requested delay is reset to
-its default value: zero.
-
-.SH EXAMPLE
-.br
-For example, a
-.B login
-application may require a failure delay of roughly 3 seconds. It will
-contain the following code:
-.sp
-.br
-.B "     pam_fail_delay(pamh, 3000000 /* micro-seconds */ );"
-.br
-.B "     pam_authenticate(pamh, 0);"
-.sp
-.br
-if the modules do not request a delay, the failure delay will be
-between 2.25 and 3.75 seconds.
-
-.br
-However, the modules, invoked in the authentication process, may
-also request delays:
-.sp
-.br
-.RB "  (module #1)   " "pam_fail_delay(pamh, 2000000);"
-.sp
-.br
-.RB "  (module #2)   " "pam_fail_delay(pamh, 4000000);"
-.sp
-.br
-in this case, it is the largest requested value that is used to
-compute the actual failed delay: here between 3 and 5 seconds.
-
-.SH "RETURN VALUE"
-Following a successful call to
-.BR pam_fail_delay "(3), " PAM_SUCCESS
-is returned.  All other returns should be considered serious failures.
-
-.SH ERRORS
-May be translated to text with
-.BR pam_strerror "(3). "
-
-.SH "CONFORMING TO"
-Under consideration by the X/Open group for future inclusion in the
-PAM RFC. 1996/1/10
-
-.SH BUGS
-.sp 2
-none known.
-
-.SH "SEE ALSO"
-
-.BR pam_start "(3), "
-.BR pam_get_item "(3) "
-and
-.BR pam_strerror "(3). "
-
-Also, see the three
-.BR Linux-PAM
-Guides, for
-.BR "System administrators" ", "
-.BR "module developers" ", "
-and
-.BR "application developers" ". "