2000-05-15 04:37:24 +00:00
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/*
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2001-05-04 03:57:05 +00:00
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* Copyright (c) 2000 Markus Friedl. All rights reserved.
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2000-09-10 08:31:17 +00:00
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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2000-05-15 04:37:24 +00:00
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*/
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#include "includes.h"
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2001-05-04 03:57:05 +00:00
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RCSID("$OpenBSD: auth.c,v 1.21 2001/03/19 17:07:23 markus Exp $");
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2000-05-15 04:37:24 +00:00
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#include "xmalloc.h"
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#include "match.h"
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2001-05-04 03:57:05 +00:00
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#include "groupaccess.h"
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#include "log.h"
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#include "servconf.h"
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2000-05-15 04:37:24 +00:00
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#include "auth.h"
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2001-05-04 03:57:05 +00:00
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#include "auth-options.h"
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#include "canohost.h"
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2000-05-15 04:37:24 +00:00
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/* import */
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extern ServerOptions options;
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/*
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2001-05-04 03:57:05 +00:00
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* Check if the user is allowed to log in via ssh. If user is listed
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* in DenyUsers or one of user's groups is listed in DenyGroups, false
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* will be returned. If AllowUsers isn't empty and user isn't listed
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* there, or if AllowGroups isn't empty and one of user's groups isn't
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* listed there, false will be returned.
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2000-05-15 04:37:24 +00:00
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* If the user's shell is not executable, false will be returned.
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* Otherwise true is returned.
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*/
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int
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allowed_user(struct passwd * pw)
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{
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struct stat st;
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2000-06-03 09:52:37 +00:00
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char *shell;
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2000-05-15 04:37:24 +00:00
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int i;
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/* Shouldn't be called if pw is NULL, but better safe than sorry... */
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2001-05-04 03:57:05 +00:00
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if (!pw || !pw->pw_name)
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2000-05-15 04:37:24 +00:00
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return 0;
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2000-06-03 09:52:37 +00:00
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/*
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* Get the shell from the password data. An empty shell field is
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* legal, and means /bin/sh.
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*/
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shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
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2000-05-15 04:37:24 +00:00
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/* deny if shell does not exists or is not executable */
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2000-06-03 09:52:37 +00:00
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if (stat(shell, &st) != 0)
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2000-05-15 04:37:24 +00:00
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return 0;
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if (!((st.st_mode & S_IFREG) && (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP))))
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return 0;
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/* Return false if user is listed in DenyUsers */
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if (options.num_deny_users > 0) {
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for (i = 0; i < options.num_deny_users; i++)
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if (match_pattern(pw->pw_name, options.deny_users[i]))
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return 0;
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}
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/* Return false if AllowUsers isn't empty and user isn't listed there */
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if (options.num_allow_users > 0) {
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for (i = 0; i < options.num_allow_users; i++)
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if (match_pattern(pw->pw_name, options.allow_users[i]))
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break;
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/* i < options.num_allow_users iff we break for loop */
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if (i >= options.num_allow_users)
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return 0;
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}
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if (options.num_deny_groups > 0 || options.num_allow_groups > 0) {
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2001-05-04 03:57:05 +00:00
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/* Get the user's group access list (primary and supplementary) */
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if (ga_init(pw->pw_name, pw->pw_gid) == 0)
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2000-05-15 04:37:24 +00:00
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return 0;
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2001-05-04 03:57:05 +00:00
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/* Return false if one of user's groups is listed in DenyGroups */
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if (options.num_deny_groups > 0)
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if (ga_match(options.deny_groups,
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options.num_deny_groups)) {
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ga_free();
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2000-05-15 04:37:24 +00:00
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return 0;
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2001-05-04 03:57:05 +00:00
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}
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2000-05-15 04:37:24 +00:00
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/*
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2001-05-04 03:57:05 +00:00
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* Return false if AllowGroups isn't empty and one of user's groups
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2000-05-15 04:37:24 +00:00
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* isn't listed there
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*/
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2001-05-04 03:57:05 +00:00
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if (options.num_allow_groups > 0)
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if (!ga_match(options.allow_groups,
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options.num_allow_groups)) {
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ga_free();
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2000-05-15 04:37:24 +00:00
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return 0;
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2001-05-04 03:57:05 +00:00
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}
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ga_free();
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2000-05-15 04:37:24 +00:00
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}
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/* We found no reason not to let this user try to log on... */
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return 1;
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}
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2001-05-04 03:57:05 +00:00
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Authctxt *
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authctxt_new(void)
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{
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Authctxt *authctxt = xmalloc(sizeof(*authctxt));
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memset(authctxt, 0, sizeof(*authctxt));
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return authctxt;
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}
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void
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auth_log(Authctxt *authctxt, int authenticated, char *method, char *info)
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{
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void (*authlog) (const char *fmt,...) = verbose;
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char *authmsg;
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/* Raise logging level */
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if (authenticated == 1 ||
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!authctxt->valid ||
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authctxt->failures >= AUTH_FAIL_LOG ||
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strcmp(method, "password") == 0)
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authlog = log;
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if (authctxt->postponed)
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authmsg = "Postponed";
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else
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authmsg = authenticated ? "Accepted" : "Failed";
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authlog("%s %s for %s%.100s from %.200s port %d%s",
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authmsg,
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method,
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authctxt->valid ? "" : "illegal user ",
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authctxt->valid && authctxt->pw->pw_uid == 0 ? "ROOT" : authctxt->user,
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get_remote_ipaddr(),
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get_remote_port(),
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info);
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}
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/*
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* Check whether root logins are disallowed.
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*/
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int
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auth_root_allowed(char *method)
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{
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switch (options.permit_root_login) {
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case PERMIT_YES:
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return 1;
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break;
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case PERMIT_NO_PASSWD:
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if (strcmp(method, "password") != 0)
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return 1;
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break;
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case PERMIT_FORCED_ONLY:
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if (forced_command) {
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log("Root login accepted for forced command.");
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return 1;
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}
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break;
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}
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log("ROOT LOGIN REFUSED FROM %.200s", get_remote_ipaddr());
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return 0;
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}
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