xref: /freebsd/contrib/unbound/edns-subnet/subnetmod.h (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*
2  * edns-subnet/subnetmod.h - edns subnet module. Must be called before validator
3  * and iterator.
4  *
5  * Copyright (c) 2013, NLnet Labs. All rights reserved.
6  *
7  * This software is open source.
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  *
13  * Redistributions of source code must retain the above copyright notice,
14  * this list of conditions and the following disclaimer.
15  *
16  * Redistributions in binary form must reproduce the above copyright notice,
17  * this list of conditions and the following disclaimer in the documentation
18  * and/or other materials provided with the distribution.
19  *
20  * Neither the name of the NLNET LABS nor the names of its contributors may
21  * be used to endorse or promote products derived from this software without
22  * specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
25  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
26  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
27  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
28  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
29  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
30  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
31  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35  */
36 /**
37  * \file
38  * subnet module for unbound.
39  */
40 
41 #ifndef SUBNETMOD_H
42 #define SUBNETMOD_H
43 #include "util/module.h"
44 #include "services/outbound_list.h"
45 #include "util/alloc.h"
46 #include "util/net_help.h"
47 #include "util/storage/slabhash.h"
48 #include "util/data/dname.h"
49 #include "edns-subnet/addrtree.h"
50 #include "edns-subnet/edns-subnet.h"
51 
52 /**
53  * Global state for the subnet module.
54  */
55 struct subnet_env {
56 	/** shared message cache
57 	 * key: struct query_info*
58 	 * data: struct subnet_msg_cache_data* */
59 	struct slabhash* subnet_msg_cache;
60 	/** access control, which upstream servers we send client address */
61 	struct ecs_whitelist* whitelist;
62 	/** allocation service */
63 	struct alloc_cache alloc;
64 	lock_rw_type biglock;
65 	/** number of messages from cache */
66 	size_t num_msg_cache;
67 	/** number of messages not from cache */
68 	size_t num_msg_nocache;
69 };
70 
71 struct subnet_msg_cache_data {
72 	struct addrtree* tree4;
73 	struct addrtree* tree6;
74 };
75 
76 struct subnet_qstate {
77 	/** We need the hash for both cache lookup and insert */
78 	hashvalue_type qinfo_hash;
79 	/** ecs_data for client communication */
80 	struct ecs_data	ecs_client_in;
81 	struct ecs_data	ecs_client_out;
82 	/** ecss data for server communication */
83 	struct ecs_data	ecs_server_in;
84 	struct ecs_data	ecs_server_out;
85 	int subnet_downstream;
86 	int subnet_sent;
87 	/** keep track of longest received scope, set after receiving CNAME for
88 	 * incoming QNAME. */
89 	int track_max_scope;
90 	/** longest received scope mask since track_max_scope is set. This value
91 	 * is used for caching and answereing to client. */
92 	uint8_t max_scope;
93 	/** has the subnet module been started with no_cache_store? */
94 	int started_no_cache_store;
95 };
96 
97 void subnet_data_delete(void* d, void* ATTR_UNUSED(arg));
98 size_t msg_cache_sizefunc(void* k, void* d);
99 
100 /**
101  * Get the module function block.
102  * @return: function block with function pointers to module methods.
103  */
104 struct module_func_block* subnetmod_get_funcblock(void);
105 
106 /** subnet module init */
107 int subnetmod_init(struct module_env* env, int id);
108 
109 /** subnet module deinit */
110 void subnetmod_deinit(struct module_env* env, int id);
111 
112 /** subnet module operate on a query */
113 void subnetmod_operate(struct module_qstate* qstate, enum module_ev event,
114 	int id, struct outbound_entry* outbound);
115 
116 /** subnet module  */
117 void subnetmod_inform_super(struct module_qstate* qstate, int id,
118 	struct module_qstate* super);
119 
120 /** subnet module cleanup query state */
121 void subnetmod_clear(struct module_qstate* qstate, int id);
122 
123 /** subnet module alloc size routine */
124 size_t subnetmod_get_mem(struct module_env* env, int id);
125 
126 /** Wrappers for static functions to unit test */
127 size_t unittest_wrapper_subnetmod_sizefunc(void *elemptr);
128 
129 /** Whitelist check, called just before query is sent upstream. */
130 int ecs_whitelist_check(struct query_info* qinfo, uint16_t flags,
131 	struct module_qstate* qstate, struct sockaddr_storage* addr,
132 	socklen_t addrlen, uint8_t* zone, size_t zonelen,
133 	struct regional* region, int id, void* cbargs);
134 
135 /** Check whether response from server contains ECS record, if so, skip cache
136  * store. Called just after parsing EDNS data from server. */
137 int ecs_edns_back_parsed(struct module_qstate* qstate, int id, void* cbargs);
138 
139 /** Remove ECS record from back_out when query resulted in REFUSED response. */
140 int ecs_query_response(struct module_qstate* qstate, struct dns_msg* response,
141 	int id, void* cbargs);
142 
143 /** mark subnet msg to be deleted */
144 void subnet_markdel(void* key);
145 
146 #endif /* SUBNETMOD_H */
147