1 /*
2  * ipsecmod/ipsecmod-whitelist.h - White listed domains for the ipsecmod to
3  * operate on.
4  *
5  * Copyright (c) 2017, 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  *
39  * Keep track of the white listed domains for ipsecmod.
40  */
41 
42 #include "config.h"
43 
44 #ifdef USE_IPSECMOD
45 #include "ipsecmod/ipsecmod.h"
46 #include "ipsecmod/ipsecmod-whitelist.h"
47 #include "util/regional.h"
48 #include "util/log.h"
49 #include "util/config_file.h"
50 #include "util/rbtree.h"
51 #include "util/data/dname.h"
52 #include "util/storage/dnstree.h"
53 #include "sldns/str2wire.h"
54 
55 /** Apply ipsecmod-whitelist string. */
56 static int
whitelist_str_cfg(rbtree_type * whitelist,const char * name)57 whitelist_str_cfg(rbtree_type* whitelist, const char* name)
58 {
59     struct name_tree_node* n;
60     size_t len;
61     uint8_t* nm = sldns_str2wire_dname(name, &len);
62     if(!nm) {
63         log_err("ipsecmod: could not parse %s for whitelist.", name);
64         return 0;
65     }
66     n = (struct name_tree_node*)calloc(1, sizeof(*n));
67     if(!n) {
68         log_err("ipsecmod: out of memory while creating whitelist.");
69         free(nm);
70         return 0;
71     }
72     n->node.key = n;
73     n->name = nm;
74     n->len = len;
75     n->labs = dname_count_labels(nm);
76     n->dclass = LDNS_RR_CLASS_IN;
77     if(!name_tree_insert(whitelist, n, nm, len, n->labs, n->dclass)) {
78         /* duplicate element ignored, idempotent */
79         free(n->name);
80         free(n);
81     }
82     return 1;
83 }
84 
85 /** Read ipsecmod-whitelist config. */
86 static int
read_whitelist(rbtree_type * whitelist,struct config_file * cfg)87 read_whitelist(rbtree_type* whitelist, struct config_file* cfg)
88 {
89 	struct config_strlist* p;
90 	for(p = cfg->ipsecmod_whitelist; p; p = p->next) {
91 		log_assert(p->str);
92 		if(!whitelist_str_cfg(whitelist, p->str))
93 			return 0;
94 	}
95 	return 1;
96 }
97 
98 int
ipsecmod_whitelist_apply_cfg(struct ipsecmod_env * ie,struct config_file * cfg)99 ipsecmod_whitelist_apply_cfg(struct ipsecmod_env* ie,
100 	struct config_file* cfg)
101 {
102 	ie->whitelist = rbtree_create(name_tree_compare);
103 	if(!read_whitelist(ie->whitelist, cfg))
104 		return 0;
105 	name_tree_init_parents(ie->whitelist);
106 	return 1;
107 }
108 
109 /** Delete ipsecmod_env->whitelist element. */
110 static void
whitelist_free(struct rbnode_type * n,void * ATTR_UNUSED (d))111 whitelist_free(struct rbnode_type* n, void* ATTR_UNUSED(d))
112 {
113 	if(n) {
114 		free(((struct name_tree_node*)n)->name);
115 		free(n);
116 	}
117 }
118 
119 /** Get memory usage of ipsecmod_env->whitelist element. */
120 static void
whitelist_get_mem(struct rbnode_type * n,void * arg)121 whitelist_get_mem(struct rbnode_type* n, void* arg)
122 {
123 	struct name_tree_node* node = (struct name_tree_node*)n;
124 	size_t* size = (size_t*) arg;
125 	if(node) {
126 		*size += sizeof(node) + node->len;
127 	}
128 }
129 
130 void
ipsecmod_whitelist_delete(rbtree_type * whitelist)131 ipsecmod_whitelist_delete(rbtree_type* whitelist)
132 {
133 	if(whitelist) {
134 		traverse_postorder(whitelist, whitelist_free, NULL);
135 		free(whitelist);
136 	}
137 }
138 
139 int
ipsecmod_domain_is_whitelisted(struct ipsecmod_env * ie,uint8_t * dname,size_t dname_len,uint16_t qclass)140 ipsecmod_domain_is_whitelisted(struct ipsecmod_env* ie, uint8_t* dname,
141 	size_t dname_len, uint16_t qclass)
142 {
143 	if(!ie->whitelist) return 1; /* No whitelist, treat as whitelisted. */
144 	return name_tree_lookup(ie->whitelist, dname, dname_len,
145 		dname_count_labels(dname), qclass) != NULL;
146 }
147 
148 size_t
ipsecmod_whitelist_get_mem(rbtree_type * whitelist)149 ipsecmod_whitelist_get_mem(rbtree_type* whitelist)
150 {
151 	size_t size = 0;
152 	if(whitelist) {
153 		traverse_postorder(whitelist, whitelist_get_mem, &size);
154 	}
155 	return size;
156 }
157 
158 #endif /* USE_IPSECMOD */
159