iter_donotq.c revision 269257 
1/*
2 * iterator/iter_donotq.c - iterative resolver donotqueryaddresses storage.
3 *
4 * Copyright (c) 2007, NLnet Labs. All rights reserved.
5 *
6 * This software is open source.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * Redistributions of source code must retain the above copyright notice,
13 * this list of conditions and the following disclaimer.
14 *
15 * Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
17 * and/or other materials provided with the distribution.
18 *
19 * Neither the name of the NLNET LABS nor the names of its contributors may
20 * be used to endorse or promote products derived from this software without
21 * specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36/**
37 * \file
38 *
39 * This file contains functions to assist the iterator module.
40 * The donotqueryaddresses are stored and looked up. These addresses
41 * (like 127.0.0.1) must not be used to send queries to, and can be
42 * discarded immediately from the server selection.
43 */
44#include "config.h"
45#include "iterator/iter_donotq.h"
46#include "util/regional.h"
47#include "util/log.h"
48#include "util/config_file.h"
49#include "util/net_help.h"
50
51struct iter_donotq*
52donotq_create(void)
53{
54	struct iter_donotq* dq = (struct iter_donotq*)calloc(1,
55		sizeof(struct iter_donotq));
56	if(!dq)
57		return NULL;
58	dq->region = regional_create();
59	if(!dq->region) {
60		donotq_delete(dq);
61		return NULL;
62	}
63	return dq;
64}
65
66void
67donotq_delete(struct iter_donotq* dq)
68{
69	if(!dq)
70		return;
71	regional_destroy(dq->region);
72	free(dq);
73}
74
75/** insert new address into donotq structure */
76static int
77donotq_insert(struct iter_donotq* dq, struct sockaddr_storage* addr,
78	socklen_t addrlen, int net)
79{
80	struct addr_tree_node* node = (struct addr_tree_node*)regional_alloc(
81		dq->region, sizeof(*node));
82	if(!node)
83		return 0;
84	if(!addr_tree_insert(&dq->tree, node, addr, addrlen, net)) {
85		verbose(VERB_QUERY, "duplicate donotquery address ignored.");
86	}
87	return 1;
88}
89
90/** apply donotq string */
91static int
92donotq_str_cfg(struct iter_donotq* dq, const char* str)
93{
94	struct sockaddr_storage addr;
95	int net;
96	socklen_t addrlen;
97	verbose(VERB_ALGO, "donotq: %s", str);
98	if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) {
99		log_err("cannot parse donotquery netblock: %s", str);
100		return 0;
101	}
102	if(!donotq_insert(dq, &addr, addrlen, net)) {
103		log_err("out of memory");
104		return 0;
105	}
106	return 1;
107}
108
109/** read donotq config */
110static int
111read_donotq(struct iter_donotq* dq, struct config_file* cfg)
112{
113	struct config_strlist* p;
114	for(p = cfg->donotqueryaddrs; p; p = p->next) {
115		log_assert(p->str);
116		if(!donotq_str_cfg(dq, p->str))
117			return 0;
118	}
119	return 1;
120}
121
122int
123donotq_apply_cfg(struct iter_donotq* dq, struct config_file* cfg)
124{
125	regional_free_all(dq->region);
126	addr_tree_init(&dq->tree);
127	if(!read_donotq(dq, cfg))
128		return 0;
129	if(cfg->donotquery_localhost) {
130		if(!donotq_str_cfg(dq, "127.0.0.0/8"))
131			return 0;
132		if(cfg->do_ip6) {
133			if(!donotq_str_cfg(dq, "::1"))
134				return 0;
135		}
136	}
137	addr_tree_init_parents(&dq->tree);
138	return 1;
139}
140
141int
142donotq_lookup(struct iter_donotq* donotq, struct sockaddr_storage* addr,
143        socklen_t addrlen)
144{
145	return addr_tree_lookup(&donotq->tree, addr, addrlen) != NULL;
146}
147
148size_t
149donotq_get_mem(struct iter_donotq* donotq)
150{
151	if(!donotq) return 0;
152	return sizeof(*donotq) + regional_get_mem(donotq->region);
153}
154