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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 * Number of bits we set per entry in the bloomfilter.
40 #define BLOOMFILTER_K 16
44 * Create a new block group.
46 * @param ctx block context in which the block group is created
47 * @param type type of the block for which we are creating the group
48 * @param nonce random value used to seed the group creation
49 * @param raw_data optional serialized prior state of the group, NULL if unavailable/fresh
50 * @param raw_data_size number of bytes in @a raw_data, 0 if unavailable/fresh
51 * @param va variable arguments specific to @a type
52 * @return block group handle, NULL if block groups are not supported
53 * by this @a type of block (this is not an error)
55 static struct GNUNET_BLOCK_Group *
56 block_plugin_dht_create_group (void *cls,
57 enum GNUNET_BLOCK_Type type,
66 guard = va_arg (va, const char *);
67 if (0 == strcmp (guard,
69 bf_size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size (va_arg (va, unsigned int),
71 else if (0 == strcmp (guard,
73 bf_size = va_arg (va, unsigned int);
79 GNUNET_break (NULL == va_arg (va, const char *));
80 return GNUNET_BLOCK_GROUP_bf_create (cls,
91 * Function called to validate a reply or a request. For
92 * request evaluation, simply pass "NULL" for the @a reply_block.
96 * @param type block type
97 * @param group block group to check against
98 * @param eo control flags
99 * @param query original query (hash)
100 * @param xquery extended query data (can be NULL, depending on type)
101 * @param xquery_size number of bytes in @a xquery
102 * @param reply_block response to validate
103 * @param reply_block_size number of bytes in @a reply_block
104 * @return characterization of result
106 static enum GNUNET_BLOCK_EvaluationResult
107 block_plugin_dht_evaluate (void *cls,
108 struct GNUNET_BLOCK_Context *ctx,
109 enum GNUNET_BLOCK_Type type,
110 struct GNUNET_BLOCK_Group *group,
111 enum GNUNET_BLOCK_EvaluationOptions eo,
112 const struct GNUNET_HashCode *query,
115 const void *reply_block,
116 size_t reply_block_size)
118 const struct GNUNET_HELLO_Message *hello;
119 struct GNUNET_PeerIdentity pid;
120 const struct GNUNET_MessageHeader *msg;
121 struct GNUNET_HashCode phash;
123 if (type != GNUNET_BLOCK_TYPE_DHT_HELLO)
124 return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
125 if (0 != xquery_size)
128 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
130 if (NULL == reply_block)
131 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
132 if (reply_block_size < sizeof (struct GNUNET_MessageHeader))
135 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
138 if (reply_block_size != ntohs (msg->size))
141 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
144 if (GNUNET_OK != GNUNET_HELLO_get_id (hello, &pid))
147 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
149 GNUNET_CRYPTO_hash (&pid,
153 GNUNET_BLOCK_GROUP_bf_test_and_set (group,
155 return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
156 return GNUNET_BLOCK_EVALUATION_OK_MORE;
161 * Function called to obtain the key for a block.
164 * @param type block type
165 * @param block block to get the key for
166 * @param block_size number of bytes @a block
167 * @param[out] key set to the key (query) for the given block
168 * @return #GNUNET_OK on success, #GNUNET_SYSERR if type not supported
169 * (or if extracting a key from a block of this type does not work)
172 block_plugin_dht_get_key (void *cls,
173 enum GNUNET_BLOCK_Type type,
176 struct GNUNET_HashCode *key)
178 const struct GNUNET_MessageHeader *msg;
179 const struct GNUNET_HELLO_Message *hello;
180 struct GNUNET_PeerIdentity *pid;
182 if (type != GNUNET_BLOCK_TYPE_DHT_HELLO)
183 return GNUNET_SYSERR;
184 if (block_size < sizeof (struct GNUNET_MessageHeader))
186 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR, "block-dht",
187 _("Block not of type %u\n"), GNUNET_BLOCK_TYPE_DHT_HELLO);
191 if (block_size != ntohs (msg->size))
193 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR, "block-dht",
194 _("Size mismatch for block\n"),
195 GNUNET_BLOCK_TYPE_DHT_HELLO);
199 memset (key, 0, sizeof (*key));
200 pid = (struct GNUNET_PeerIdentity *) key;
201 if (GNUNET_OK != GNUNET_HELLO_get_id (hello, pid))
203 GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR, "block-dht",
204 _("Block of type %u is malformed\n"),
205 GNUNET_BLOCK_TYPE_DHT_HELLO);
213 * Entry point for the plugin.
216 libgnunet_plugin_block_dht_init (void *cls)
218 static enum GNUNET_BLOCK_Type types[] =
220 GNUNET_BLOCK_TYPE_DHT_HELLO,
221 GNUNET_BLOCK_TYPE_ANY /* end of list */
223 struct GNUNET_BLOCK_PluginFunctions *api;
225 api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions);
226 api->evaluate = &block_plugin_dht_evaluate;
227 api->get_key = &block_plugin_dht_get_key;
228 api->create_group = &block_plugin_dht_create_group;
235 * Exit point from the plugin.
238 libgnunet_plugin_block_dht_done (void *cls)
240 struct GNUNET_BLOCK_PluginFunctions *api = cls;
246 /* end of plugin_block_dht.c */