1 /* $NetBSD: throttle.c,v 1.7 2011/03/14 17:18:13 tteras Exp $ */
2
3 /* Id: throttle.c,v 1.5 2006/04/05 20:54:50 manubsd Exp */
4
5 /*
6 * Copyright (C) 2004 Emmanuel Dreyfus
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the project nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #include "config.h"
35
36 #include <stdlib.h>
37 #include <string.h>
38 #include <sys/param.h>
39 #include <sys/queue.h>
40 #include <netinet/in.h>
41 #include <resolv.h>
42
43 #include "vmbuf.h"
44 #include "misc.h"
45 #include "plog.h"
46 #include "throttle.h"
47 #include "sockmisc.h"
48 #include "isakmp_var.h"
49 #include "isakmp.h"
50 #include "isakmp_xauth.h"
51 #include "isakmp_cfg.h"
52 #include "gcmalloc.h"
53
54 static struct throttle_list throttle_list =
55 TAILQ_HEAD_INITIALIZER(throttle_list);
56
57 struct throttle_entry *
throttle_add(addr)58 throttle_add(addr)
59 struct sockaddr *addr;
60 {
61 struct throttle_entry *te;
62 struct timeval now, penalty;
63 size_t len;
64
65 len = sizeof(*te)
66 - sizeof(struct sockaddr_storage)
67 + sysdep_sa_len(addr);
68
69 if ((te = racoon_malloc(len)) == NULL)
70 return NULL;
71
72 sched_get_monotonic_time(&now);
73 penalty.tv_sec = isakmp_cfg_config.auth_throttle;
74 penalty.tv_usec = 0;
75 timeradd(&now, &penalty, &te->penalty_ends);
76
77 memcpy(&te->host, addr, sysdep_sa_len(addr));
78 TAILQ_INSERT_HEAD(&throttle_list, te, next);
79
80 return te;
81 }
82
83 int
throttle_host(addr,authfail)84 throttle_host(addr, authfail)
85 struct sockaddr *addr;
86 int authfail;
87 {
88 struct throttle_entry *te;
89 struct timeval now, res;
90 int found = 0;
91
92 if (isakmp_cfg_config.auth_throttle == 0)
93 return 0;
94
95 sched_get_monotonic_time(&now);
96 restart:
97 RACOON_TAILQ_FOREACH_REVERSE(te, &throttle_list, throttle_list, next) {
98 /*
99 * Remove outdated entries
100 */
101 if (timercmp(&te->penalty_ends, &now, <)) {
102 TAILQ_REMOVE(&throttle_list, te, next);
103 racoon_free(te);
104 goto restart;
105 }
106
107 if (cmpsaddr(addr, (struct sockaddr *) &te->host) <= CMPSADDR_WOP_MATCH) {
108 found = 1;
109 break;
110 }
111 }
112
113 /*
114 * No match, if auth failed, allocate a new throttle entry
115 * give no penalty even on error: this is the first time
116 * and we are indulgent.
117 */
118 if (!found) {
119 if (authfail) {
120 if ((te = throttle_add(addr)) == NULL) {
121 plog(LLV_ERROR, LOCATION, NULL,
122 "Throttle insertion failed\n");
123 return isakmp_cfg_config.auth_throttle;
124 }
125 }
126 return 0;
127 } else {
128 /*
129 * We had a match and auth failed, increase penalty.
130 */
131 if (authfail) {
132 struct timeval remaining, penalty;
133
134 timersub(&te->penalty_ends, &now, &remaining);
135 penalty.tv_sec = isakmp_cfg_config.auth_throttle;
136 penalty.tv_usec = 0;
137 timeradd(&penalty, &remaining, &res);
138 if (res.tv_sec >= THROTTLE_PENALTY_MAX) {
139 res.tv_sec = THROTTLE_PENALTY_MAX;
140 res.tv_usec = 0;
141 }
142 timeradd(&now, &res, &te->penalty_ends);
143 }
144 }
145
146 timersub(&te->penalty_ends, &now, &res);
147 return res.tv_sec;
148 }
149
150