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13 General Public License for more details.
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22 * @file dht/plugin_block_dht.c
23 * @brief block plugin for DHT internals (right now, find-peer requests only);
24 * other plugins should be used to store "useful" data in the
25 * DHT (see fs block plugin)
26 * @author Christian Grothoff
29 #include "gnunet_constants.h"
30 #include "gnunet_hello_lib.h"
31 #include "gnunet_block_plugin.h"
32 #include "gnunet_block_group_lib.h"
34 #define DEBUG_DHT GNUNET_EXTRA_LOGGING
37 * How big is the BF we use for DHT blocks?
43 * Create a new block group.
45 * @param ctx block context in which the block group is created
46 * @param type type of the block for which we are creating the group
47 * @param nonce random value used to seed the group creation
48 * @param raw_data optional serialized prior state of the group, NULL if unavailable/fresh
49 * @param raw_data_size number of bytes in @a raw_data, 0 if unavailable/fresh
50 * @param va variable arguments specific to @a type
51 * @return block group handle, NULL if block groups are not supported
52 * by this @a type of block (this is not an error)
54 static struct GNUNET_BLOCK_Group *
55 block_plugin_dht_create_group (void *cls,
56 enum GNUNET_BLOCK_Type type,
62 return GNUNET_BLOCK_GROUP_bf_create (cls,
64 GNUNET_CONSTANTS_BLOOMFILTER_K,
73 * Function called to validate a reply or a request. For
74 * request evaluation, simply pass "NULL" for the @a reply_block.
77 * @param type block type
78 * @param group block group to check against
79 * @param eo control flags
80 * @param query original query (hash)
81 * @param xquery extended query data (can be NULL, depending on type)
82 * @param xquery_size number of bytes in @a xquery
83 * @param reply_block response to validate
84 * @param reply_block_size number of bytes in @a reply_block
85 * @return characterization of result
87 static enum GNUNET_BLOCK_EvaluationResult
88 block_plugin_dht_evaluate (void *cls,
89 enum GNUNET_BLOCK_Type type,
90 struct GNUNET_BLOCK_Group *group,
91 enum GNUNET_BLOCK_EvaluationOptions eo,
92 const struct GNUNET_HashCode *query,
95 const void *reply_block,
96 size_t reply_block_size)
98 const struct GNUNET_HELLO_Message *hello;
99 struct GNUNET_PeerIdentity pid;
100 const struct GNUNET_MessageHeader *msg;
101 struct GNUNET_HashCode phash;
103 if (type != GNUNET_BLOCK_TYPE_DHT_HELLO)
104 return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
105 if (0 != xquery_size)
108 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
110 if (NULL == reply_block)
111 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
112 if (reply_block_size < sizeof (struct GNUNET_MessageHeader))
115 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
118 if (reply_block_size != ntohs (msg->size))
121 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
124 if (GNUNET_OK != GNUNET_HELLO_get_id (hello, &pid))
127 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
129 GNUNET_CRYPTO_hash (&pid,
133 GNUNET_BLOCK_GROUP_bf_test_and_set (group,
135 return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
136 return GNUNET_BLOCK_EVALUATION_OK_MORE;
141 * Function called to obtain the key for a block.
144 * @param type block type
145 * @param block block to get the key for
146 * @param block_size number of bytes @a block
147 * @param[out] key set to the key (query) for the given block
148 * @return #GNUNET_OK on success, #GNUNET_SYSERR if type not supported
149 * (or if extracting a key from a block of this type does not work)
152 block_plugin_dht_get_key (void *cls,
153 enum GNUNET_BLOCK_Type type,
156 struct GNUNET_HashCode *key)
158 const struct GNUNET_MessageHeader *msg;
159 const struct GNUNET_HELLO_Message *hello;
160 struct GNUNET_PeerIdentity *pid;
162 if (type != GNUNET_BLOCK_TYPE_DHT_HELLO)
163 return GNUNET_SYSERR;
164 if (block_size < sizeof (struct GNUNET_MessageHeader))
166 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR, "block-dht",
167 _("Block not of type %u\n"), GNUNET_BLOCK_TYPE_DHT_HELLO);
171 if (block_size != ntohs (msg->size))
173 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR, "block-dht",
174 _("Size mismatch for block\n"),
175 GNUNET_BLOCK_TYPE_DHT_HELLO);
179 memset (key, 0, sizeof (*key));
180 pid = (struct GNUNET_PeerIdentity *) key;
181 if (GNUNET_OK != GNUNET_HELLO_get_id (hello, pid))
183 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR, "block-dht",
184 _("Block of type %u is malformed\n"),
185 GNUNET_BLOCK_TYPE_DHT_HELLO);
193 * Entry point for the plugin.
196 libgnunet_plugin_block_dht_init (void *cls)
198 static enum GNUNET_BLOCK_Type types[] =
200 GNUNET_BLOCK_TYPE_DHT_HELLO,
201 GNUNET_BLOCK_TYPE_ANY /* end of list */
203 struct GNUNET_BLOCK_PluginFunctions *api;
205 api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions);
206 api->evaluate = &block_plugin_dht_evaluate;
207 api->get_key = &block_plugin_dht_get_key;
208 api->create_group = &block_plugin_dht_create_group;
215 * Exit point from the plugin.
218 libgnunet_plugin_block_dht_done (void *cls)
220 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
226 /* end of plugin_block_dht.c */