1 files changed, 226 insertions, 0 deletions
diff --git a/src/gns/plugin_block_gns.c b/src/gns/plugin_block_gns.c
new file mode 100644
index 0000000..a4d6ad9
--- /dev/null
+++ b/src/gns/plugin_block_gns.c
@@ -0,0 +1,226 @@
+/*
+     This file is part of GNUnet
+     (C) 2010 Christian Grothoff (and other contributing authors)
+
+     GNUnet is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     GNUnet is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file gns/plugin_block_gns.c
+ * @brief blocks used for GNS records
+ * @author Martin Schanzenbach
+ */
+
+#include "platform.h"
+#include "gnunet_block_plugin.h"
+#include "gnunet_namestore_service.h"
+#include "block_gns.h"
+#include "gnunet_signatures.h"
+
+/**
+ * Number of bits we set per entry in the bloomfilter.
+ * Do not change! -from fs
+ */
+#define BLOOMFILTER_K 16
+
+/**
+ * Function called to validate a reply or a request.  For
+ * request evaluation, simply pass "NULL" for the reply_block.
+ * Note that it is assumed that the reply has already been
+ * matched to the key (and signatures checked) as it would
+ * be done with the "get_key" function.
+ *
+ * @param cls closure
+ * @param type block type
+ * @param query original query (hash)
+ * @param bf pointer to bloom filter associated with query; possibly updated (!)
+ * @param bf_mutator mutation value for bf
+ * @param xquery extrended query data (can be NULL, depending on type)
+ * @param xquery_size number of bytes in xquery
+ * @param reply_block response to validate
+ * @param reply_block_size number of bytes in reply block
+ * @return characterization of result
+ */
+static enum GNUNET_BLOCK_EvaluationResult
+block_plugin_gns_evaluate (void *cls, enum GNUNET_BLOCK_Type type,
+                          const GNUNET_HashCode * query,
+                          struct GNUNET_CONTAINER_BloomFilter **bf,
+                          int32_t bf_mutator, const void *xquery,
+                          size_t xquery_size, const void *reply_block,
+                          size_t reply_block_size)
+{
+  if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD)
+    return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
+  if (reply_block_size == 0)
+    return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
+  
+  char* name;
+  GNUNET_HashCode pkey_hash;
+  GNUNET_HashCode query_key;
+  GNUNET_HashCode name_hash;
+  GNUNET_HashCode mhash;
+  GNUNET_HashCode chash;
+  struct GNSNameRecordBlock *nrb;
+  struct GNSRecordBlock *rb;
+  uint32_t rd_count;
+  
+  nrb = (struct GNSNameRecordBlock *)reply_block;
+  name = (char*)&nrb[1];
+  GNUNET_CRYPTO_hash(&nrb->public_key,
+                     sizeof(nrb->public_key),
+                     &pkey_hash);
+
+  GNUNET_CRYPTO_hash(name, strlen(name), &name_hash);
+
+  GNUNET_CRYPTO_hash_xor(&pkey_hash, &name_hash, &query_key);
+  
+  /* Check query key against public key */
+  if (0 != GNUNET_CRYPTO_hash_cmp(query, &query_key))
+    return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
+  
+  rd_count = ntohl(nrb->rd_count);
+
+  struct GNUNET_NAMESTORE_RecordData rd[rd_count];
+  int i = 0;
+  int record_match = 0;
+  uint32_t record_xquery = ntohl(*((uint32_t*)xquery));
+  rb = (struct GNSRecordBlock*)(&name[strlen(name) + 1]);
+
+  for (i=0; i<rd_count; i++)
+  {
+    rd[i].record_type = ntohl(rb->type);
+    rd[i].expiration =
+      GNUNET_TIME_absolute_ntoh(rb->expiration);
+    rd[i].data_size = ntohl(rb->data_length);
+    rd[i].flags = ntohl(rb->flags);
+    rd[i].data = (char*)&rb[1];
+    rb = (struct GNSRecordBlock *)((char*)&rb[1] + rd[i].data_size);
+    
+    if (xquery_size == 0)
+     continue;
+    
+    if (rd[i].record_type == record_xquery)
+    {
+      record_match++;
+    }
+  }
+  
+
+  /*if (GNUNET_OK != GNUNET_NAMESTORE_verify_signature (&nrb->public_key,
+                                                      name,
+                                                      rd_count,
+                                                      rd,
+                                                      NULL))
+  {
+    GNUNET_log(GNUNET_ERROR_TYPE_INFO, "Signature invalid\n");
+    return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
+  }*/
+  
+  //No record matches query
+  if ((xquery_size > 0) && (record_match == 0))
+    return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
+
+  GNUNET_log(GNUNET_ERROR_TYPE_INFO, "Records match\n");
+  //FIXME do bf check before or after crypto??
+  if (NULL != bf)
+  {
+    GNUNET_CRYPTO_hash(reply_block, reply_block_size, &chash);
+    GNUNET_BLOCK_mingle_hash(&chash, bf_mutator, &mhash);
+    if (NULL != *bf)
+    {
+      GNUNET_log(GNUNET_ERROR_TYPE_INFO, "Check BF\n");
+      if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test(*bf, &mhash))
+        return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
+    }
+    else
+    {
+      *bf = GNUNET_CONTAINER_bloomfilter_init(NULL, 8, BLOOMFILTER_K);
+    }
+    GNUNET_CONTAINER_bloomfilter_add(*bf, &mhash);
+  }
+  GNUNET_log(GNUNET_ERROR_TYPE_INFO, "No dup\n");
+  return GNUNET_BLOCK_EVALUATION_OK_MORE;
+}
+
+
+/**
+ * Function called to obtain the key for a block.
+ *
+ * @param cls closure
+ * @param type block type
+ * @param block block to get the key for
+ * @param block_size number of bytes in block
+ * @param key set to the key (query) for the given block
+ * @return GNUNET_OK on success, GNUNET_SYSERR if type not supported
+ *         (or if extracting a key from a block of this type does not work)
+ */
+static int
+block_plugin_gns_get_key (void *cls, enum GNUNET_BLOCK_Type type,
+                         const void *block, size_t block_size,
+                         GNUNET_HashCode * key)
+{
+  if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD)
+    return GNUNET_SYSERR;
+  GNUNET_HashCode name_hash;
+  GNUNET_HashCode pkey_hash;
+  struct GNSNameRecordBlock *nrb = (struct GNSNameRecordBlock *)block;
+
+  GNUNET_CRYPTO_hash(&nrb[1], strlen((char*)&nrb[1]), &name_hash);
+  GNUNET_CRYPTO_hash(&nrb->public_key,
+                     sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
+                     &pkey_hash);
+
+  GNUNET_CRYPTO_hash_xor(&name_hash, &pkey_hash, key);
+  
+  //FIXME calculate key from name and hash(pkey) here
+  return GNUNET_OK;
+}
+
+
+/**
+ * Entry point for the plugin.
+ */
+void *
+libgnunet_plugin_block_gns_init (void *cls)
+{
+  static enum GNUNET_BLOCK_Type types[] =
+  {
+    GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
+    GNUNET_BLOCK_TYPE_ANY       /* end of list */
+  };
+  struct GNUNET_BLOCK_PluginFunctions *api;
+
+  api = GNUNET_malloc (sizeof (struct GNUNET_BLOCK_PluginFunctions));
+  api->evaluate = &block_plugin_gns_evaluate;
+  api->get_key = &block_plugin_gns_get_key;
+  api->types = types;
+  return api;
+}
+
+
+/**
+ * Exit point from the plugin.
+ */
+void *
+libgnunet_plugin_block_gns_done (void *cls)
+{
+  struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
+
+  GNUNET_free (api);
+  return NULL;
+}
+
+/* end of plugin_block_gns.c */