freebsd-dev/contrib/blacklist/lib/blacklist.c
Kurt Lidl 5de2cc52e9 Extend libblacklist support with new action types
The original blacklist library supported two notification types:
 - failed auth attempt, which incremented the failed login count
   by one for the remote address
 - successful auth attempt, which reset the failed login count
   to zero for that remote address

When the failed login count reached the limit in the configuration
file, the remote address would be blocked by a packet filter.

This patch implements a new notification type, "abusive behavior",
and accepts, but does not act on an additional type, "bad username".
It is envisioned that a system administrator will configure a small
list of "known bad usernames" that should be blocked immediately.

Reviewed by:	emaste
MFC after:	3 days
Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D10604
2017-05-23 19:03:07 +00:00

109 lines
3.1 KiB
C

/* $NetBSD: blacklist.c,v 1.5 2015/01/22 16:19:53 christos Exp $ */
/*-
* Copyright (c) 2014 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/cdefs.h>
__RCSID("$NetBSD: blacklist.c,v 1.5 2015/01/22 16:19:53 christos Exp $");
#include <stdio.h>
#include <bl.h>
#include <stdarg.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <syslog.h>
int
blacklist_sa(int action, int rfd, const struct sockaddr *sa, socklen_t salen,
const char *msg)
{
struct blacklist *bl;
int rv;
if ((bl = blacklist_open()) == NULL)
return -1;
rv = blacklist_sa_r(bl, action, rfd, sa, salen, msg);
blacklist_close(bl);
return rv;
}
int
blacklist_sa_r(struct blacklist *bl, int action, int rfd,
const struct sockaddr *sa, socklen_t slen, const char *msg)
{
int internal_action;
/* internal values are not the same as user application values */
switch (action) {
case BLACKLIST_AUTH_FAIL:
internal_action = BL_ADD;
break;
case BLACKLIST_AUTH_OK:
internal_action = BL_DELETE;
break;
case BLACKLIST_ABUSIVE_BEHAVIOR:
internal_action = BL_ABUSE;
break;
case BLACKLIST_BAD_USER:
internal_action = BL_BADUSER;
break;
default:
internal_action = BL_INVALID;
break;
}
return bl_send(bl, internal_action, rfd, sa, slen, msg);
}
int
blacklist(int action, int rfd, const char *msg)
{
return blacklist_sa(action, rfd, NULL, 0, msg);
}
int
blacklist_r(struct blacklist *bl, int action, int rfd, const char *msg)
{
return blacklist_sa_r(bl, action, rfd, NULL, 0, msg);
}
struct blacklist *
blacklist_open(void) {
return bl_create(false, NULL, vsyslog);
}
void
blacklist_close(struct blacklist *bl)
{
bl_destroy(bl);
}