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3 Copyright (C) 2013 GNUnet e.V.
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6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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17 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 Boston, MA 02110-1301, USA.
22 * @file dns/plugin_block_dns.c
23 * @brief block plugin for advertising a DNS exit service
24 * @author Christian Grothoff
26 * Note that this plugin might more belong with EXIT and PT
27 * as those two are using this type of block. Still, this
28 * might be a natural enough place for people to find the code...
31 #include "gnunet_block_plugin.h"
32 #include "block_dns.h"
33 #include "gnunet_signatures.h"
37 * Function called to validate a reply or a request. For
38 * request evaluation, simply pass "NULL" for the reply_block.
41 * @param type block type
42 * @param eo control flags
43 * @param query original query (hash)
44 * @param bf pointer to bloom filter associated with query; possibly updated (!)
45 * @param bf_mutator mutation value for bf
46 * @param xquery extended query data (can be NULL, depending on type)
47 * @param xquery_size number of bytes in @a xquery
48 * @param reply_block response to validate
49 * @param reply_block_size number of bytes in @a reply_block
50 * @return characterization of result
52 static enum GNUNET_BLOCK_EvaluationResult
53 block_plugin_dns_evaluate (void *cls,
54 enum GNUNET_BLOCK_Type type,
55 enum GNUNET_BLOCK_EvaluationOptions eo,
56 const struct GNUNET_HashCode * query,
57 struct GNUNET_CONTAINER_BloomFilter **bf,
61 const void *reply_block,
62 size_t reply_block_size)
64 const struct GNUNET_DNS_Advertisement *ad;
68 case GNUNET_BLOCK_TYPE_DNS:
70 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
72 if (0 == reply_block_size)
73 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
75 if (sizeof (struct GNUNET_DNS_Advertisement) != reply_block_size)
78 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
82 if (ntohl (ad->purpose.size) !=
83 sizeof (struct GNUNET_DNS_Advertisement) -
84 sizeof (struct GNUNET_CRYPTO_EddsaSignature))
87 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
90 GNUNET_TIME_absolute_get_remaining (GNUNET_TIME_absolute_ntoh
91 (ad->expiration_time)).rel_value_us)
93 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
94 "DNS advertisement has expired\n");
95 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
98 GNUNET_CRYPTO_eddsa_verify (GNUNET_SIGNATURE_PURPOSE_DNS_RECORD,
101 &ad->peer.public_key))
104 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
106 return GNUNET_BLOCK_EVALUATION_OK_MORE;
108 return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
114 * Function called to obtain the key for a block.
117 * @param type block type
118 * @param block block to get the key for
119 * @param block_size number of bytes in @a block
120 * @param key set to the key (query) for the given block
121 * @return #GNUNET_OK on success, #GNUNET_SYSERR if type not supported
122 * (or if extracting a key from a block of this type does not work)
125 block_plugin_dns_get_key (void *cls,
126 enum GNUNET_BLOCK_Type type,
129 struct GNUNET_HashCode *key)
131 /* we cannot extract a key from a block of this type */
132 return GNUNET_SYSERR;
137 * Entry point for the plugin.
140 libgnunet_plugin_block_dns_init (void *cls)
142 static enum GNUNET_BLOCK_Type types[] =
144 GNUNET_BLOCK_TYPE_DNS,
145 GNUNET_BLOCK_TYPE_ANY /* end of list */
147 struct GNUNET_BLOCK_PluginFunctions *api;
149 api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions);
150 api->evaluate = &block_plugin_dns_evaluate;
151 api->get_key = &block_plugin_dns_get_key;
158 * Exit point from the plugin.
161 libgnunet_plugin_block_dns_done (void *cls)
163 struct GNUNET_BLOCK_PluginFunctions *api = cls;
169 /* end of plugin_block_dns.c */