2 * util/edns.c - handle base EDNS options.
4 * Copyright (c) 2018, NLnet Labs. All rights reserved.
6 * This software is open source.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * Redistributions of source code must retain the above copyright notice,
13 * this list of conditions and the following disclaimer.
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.
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.
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.
39 * This file contains functions for base EDNS options.
43 #include "util/edns.h"
44 #include "util/config_file.h"
45 #include "util/netevent.h"
46 #include "util/net_help.h"
47 #include "util/regional.h"
48 #include "util/data/msgparse.h"
49 #include "util/data/msgreply.h"
56 struct edns_strings* edns_strings_create(void)
58 struct edns_strings* edns_strings = calloc(1,
59 sizeof(struct edns_strings));
62 if(!(edns_strings->region = regional_create())) {
63 edns_strings_delete(edns_strings);
69 void edns_strings_delete(struct edns_strings* edns_strings)
73 regional_destroy(edns_strings->region);
78 edns_strings_client_insert(struct edns_strings* edns_strings,
79 struct sockaddr_storage* addr, socklen_t addrlen, int net,
82 struct edns_string_addr* esa = regional_alloc_zero(edns_strings->region,
83 sizeof(struct edns_string_addr));
86 esa->string_len = strlen(string);
87 esa->string = regional_alloc_init(edns_strings->region, string,
91 if(!addr_tree_insert(&edns_strings->client_strings, &esa->node, addr,
93 verbose(VERB_QUERY, "duplicate EDNS client string ignored.");
98 int edns_strings_apply_cfg(struct edns_strings* edns_strings,
99 struct config_file* config)
101 struct config_str2list* c;
102 regional_free_all(edns_strings->region);
103 addr_tree_init(&edns_strings->client_strings);
105 for(c=config->edns_client_strings; c; c=c->next) {
106 struct sockaddr_storage addr;
109 log_assert(c->str && c->str2);
111 if(!netblockstrtoaddr(c->str, UNBOUND_DNS_PORT, &addr, &addrlen,
113 log_err("cannot parse EDNS client string IP netblock: "
117 if(!edns_strings_client_insert(edns_strings, &addr, addrlen,
119 log_err("out of memory while adding EDNS strings");
123 edns_strings->client_string_opcode = config->edns_client_string_opcode;
125 addr_tree_init_parents(&edns_strings->client_strings);
129 struct edns_string_addr*
130 edns_string_addr_lookup(rbtree_type* tree, struct sockaddr_storage* addr,
133 return (struct edns_string_addr*)addr_tree_lookup(tree, addr, addrlen);
136 static int edns_keepalive(struct edns_data* edns_out, struct edns_data* edns_in,
137 struct comm_point* c, struct regional* region)
139 if(c->type == comm_udp)
142 /* To respond with a Keepalive option, the client connection
143 * must have received one message with a TCP Keepalive EDNS option,
144 * and that option must have 0 length data. Subsequent messages
145 * sent on that connection will have a TCP Keepalive option.
147 if(c->tcp_keepalive ||
148 edns_opt_list_find(edns_in->opt_list, LDNS_EDNS_KEEPALIVE)) {
149 int keepalive = c->tcp_timeout_msec / 100;
151 data[0] = (uint8_t)((keepalive >> 8) & 0xff);
152 data[1] = (uint8_t)(keepalive & 0xff);
153 if(!edns_opt_list_append(&edns_out->opt_list, LDNS_EDNS_KEEPALIVE,
154 sizeof(data), data, region))
156 c->tcp_keepalive = 1;
161 int apply_edns_options(struct edns_data* edns_out, struct edns_data* edns_in,
162 struct config_file* cfg, struct comm_point* c, struct regional* region)
164 if(cfg->do_tcp_keepalive &&
165 !edns_keepalive(edns_out, edns_in, c, region))