Imported Upstream version 0.9.2upstream/0.9.2

1 files changed, 368 insertions, 0 deletions

diff --git a/src/include/gnunet_namestore_service.h b/src/include/gnunet_namestore_service.h
new file mode 100644
index 0000000..8ab2ce8
--- /dev/null
+++ b/src/include/gnunet_namestore_service.h
@@ -0,0 +1,368 @@
+/*
+     This file is part of GNUnet
+     (C) 2012 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 2, 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 include/gnunet_namestore_service.h
+ * @brief API that can be used to store naming information on a GNUnet node;
+ * @author Christian Grothoff
+ *
+ * Other functions we might want:
+ * - enumerate all known zones
+ * - convenience function to gather record and the full affilliated stree
+ *   in one shot
+ */
+
+#ifndef GNUNET_NAMESTORE_SERVICE_H
+#define GNUNET_NAMESTORE_SERVICE_H
+
+#include "gnunet_util_lib.h"
+#include "gnunet_block_lib.h"
+
+#ifdef __cplusplus
+extern "C"
+{
+#if 0                           /* keep Emacsens' auto-indent happy */
+}
+#endif
+#endif
+
+/**
+ * Entry in the queue.
+ */
+struct GNUNET_NAMESTORE_QueueEntry;
+
+/**
+ * Handle to the namestore service.
+ */
+struct GNUNET_NAMESTORE_Handle;
+
+/**
+ * Handle to the namestore zone iterator.
+ */
+struct GNUNET_NAMESTORE_ZoneIterator;
+
+/**
+ * Maximum size of a value that can be stored in the namestore.
+ */
+#define GNUNET_NAMESTORE_MAX_VALUE_SIZE (63 * 1024)
+
+/**
+ * Connect to the namestore service.
+ *
+ * @param cfg configuration to use
+ * @return handle to use to access the service
+ */
+struct GNUNET_NAMESTORE_Handle *
+GNUNET_NAMESTORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg);
+
+
+/**
+ * Disconnect from the namestore service (and free associated
+ * resources).
+ *
+ * @param h handle to the namestore
+ * @param drop set to GNUNET_YES to delete all data in namestore (!)
+ */
+void
+GNUNET_NAMESTORE_disconnect (struct GNUNET_NAMESTORE_Handle *h, int drop);
+
+
+/**
+ * Continuation called to notify client about result of the
+ * operation.
+ *
+ * @param cls closure
+ * @param success GNUNET_SYSERR on failure (including timeout/queue drop/failure to validate)
+ *                GNUNET_NO if content was already there
+ *                GNUNET_YES (or other positive value) on success
+ * @param emsg NULL on success, otherwise an error message
+ */
+typedef void (*GNUNET_NAMESTORE_ContinuationWithStatus) (void *cls,
+                                                         int32_t success,
+                                                         const char *emsg);
+
+
+/**
+ * Flags that can be set for a record.
+ */
+enum GNUNET_NAMESTORE_RecordFlags
+{
+  
+  /**
+   * No special options.
+   */
+  GNUNET_NAMESTORE_RF_NONE = 0,
+
+  /**
+   * This peer is the authority for this record; it must thus
+   * not be deleted (other records can be deleted if we run
+   * out of space).
+   */
+  GNUNET_NAMESTORE_RF_AUTHORITY = 1,
+
+  /**
+   * This is a private record of this peer and it should
+   * thus not be handed out to other peers.
+   */
+  GNUNET_NAMESTORE_RF_PRIVATE = 2
+
+};
+
+
+/**
+ * A GNS record.
+ */
+struct GNUNET_NAMESTORE_RecordData
+{
+
+  /**
+   * Binary value stored in the DNS record.
+   */
+  const void *data;
+
+  /**
+   * Expiration time for the DNS record.
+   */
+  struct GNUNET_TIME_Absolute expiration;
+
+  /**
+   * Number of bytes in 'data'.
+   */
+  size_t data_size;
+
+  /**
+   * Type of the GNS/DNS record.
+   */
+  uint32_t record_type;
+
+  /**
+   * Flags for the record.
+   */
+  enum GNUNET_NAMESTORE_RecordFlags flags;
+};
+
+
+/**
+ * Store an item in the namestore.  If the item is already present,
+ * the expiration time is updated to the max of the existing time and
+ * the new time.  This API is used when we cache signatures from other
+ * authorities.
+ *
+ * @param h handle to the namestore
+ * @param zone_key public key of the zone
+ * @param name name that is being mapped (at most 255 characters long)
+ * @param expire when does the corresponding block in the DHT expire (until
+ *               when should we never do a DHT lookup for the same name again)?
+ * @param rd_count number of entries in 'rd' array
+ * @param rd array of records with data to store
+ * @param signature signature for all the records in the zone under the given name
+ * @param cont continuation to call when done
+ * @param cont_cls closure for cont
+ * @return handle to abort the request
+ */
+struct GNUNET_NAMESTORE_QueueEntry *
+GNUNET_NAMESTORE_record_put (struct GNUNET_NAMESTORE_Handle *h,
+			     const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *zone_key,
+			     const char *name,
+			     struct GNUNET_TIME_Absolute expire,
+			     unsigned int rd_count,
+			     const struct GNUNET_NAMESTORE_RecordData *rd,
+			     const struct GNUNET_CRYPTO_RsaSignature *signature,
+			     GNUNET_NAMESTORE_ContinuationWithStatus cont,
+			     void *cont_cls);
+
+
+/**
+ * Check if a signature is valid.  This API is used by the GNS Block
+ * to validate signatures received from the network.
+ *
+ * @param public_key public key of the zone
+ * @param name name that is being mapped (at most 255 characters long)
+ * @param rd_count number of entries in 'rd' array
+ * @param rd array of records with data to store
+ * @param signature signature for all the records in the zone under the given name
+ * @return GNUNET_OK if the signature is valid
+ */
+int
+GNUNET_NAMESTORE_verify_signature (const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *public_key,
+				   const char *name,
+				   unsigned int rd_count,
+				   const struct GNUNET_NAMESTORE_RecordData *rd,
+				   const struct GNUNET_CRYPTO_RsaSignature *signature);
+
+
+/**
+ * Store an item in the namestore.  If the item is already present,
+ * the expiration time is updated to the max of the existing time and
+ * the new time.  This API is used by the authority of a zone.
+ *
+ * @param h handle to the namestore
+ * @param pkey private key of the zone
+ * @param name name that is being mapped (at most 255 characters long)
+ * @param rd record data to store
+ * @param cont continuation to call when done
+ * @param cont_cls closure for cont
+ * @return handle to abort the request
+ */
+struct GNUNET_NAMESTORE_QueueEntry *
+GNUNET_NAMESTORE_record_create (struct GNUNET_NAMESTORE_Handle *h,
+				const struct GNUNET_CRYPTO_RsaPrivateKey *pkey,
+				const char *name,
+				const struct GNUNET_NAMESTORE_RecordData *rd,
+				GNUNET_NAMESTORE_ContinuationWithStatus cont,
+				void *cont_cls);
+
+
+/**
+ * Explicitly remove some content from the database.  The
+ * "cont"inuation will be called with status "GNUNET_OK" if content
+ * was removed, "GNUNET_NO" if no matching entry was found and
+ * "GNUNET_SYSERR" on all other types of errors.
+ * This API is used by the authority of a zone.
+ *
+ * @param h handle to the namestore
+ * @param pkey private key of the zone
+ * @param name name that is being mapped (at most 255 characters long)
+ * @param rd record data
+ * @param cont continuation to call when done
+ * @param cont_cls closure for cont
+ * @return handle to abort the request
+ */
+struct GNUNET_NAMESTORE_QueueEntry *
+GNUNET_NAMESTORE_record_remove (struct GNUNET_NAMESTORE_Handle *h,
+				const struct GNUNET_CRYPTO_RsaPrivateKey *pkey,
+				const char *name,
+				const struct GNUNET_NAMESTORE_RecordData *rd,
+				GNUNET_NAMESTORE_ContinuationWithStatus cont,
+				void *cont_cls);
+
+
+/**
+ * Process a record that was stored in the namestore.
+ *
+ * @param cls closure
+ * @param zone_key public key of the zone
+ * @param expire when does the corresponding block in the DHT expire (until
+ *               when should we never do a DHT lookup for the same name again)?; 
+ *               GNUNET_TIME_UNIT_ZERO_ABS if there are no records of any type in the namestore,
+ *               or the expiration time of the block in the namestore (even if there are zero
+ *               records matching the desired record type)
+ * @param name name that is being mapped (at most 255 characters long)
+ * @param rd_count number of entries in 'rd' array
+ * @param rd array of records with data to store
+ * @param signature signature of the record block, NULL if signature is unavailable (i.e. 
+ *        because the user queried for a particular record type only)
+ */
+typedef void (*GNUNET_NAMESTORE_RecordProcessor) (void *cls,
+						  const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *zone_key,
+						  struct GNUNET_TIME_Absolute expire,			    
+						  const char *name,
+						  unsigned int rd_count,
+						  const struct GNUNET_NAMESTORE_RecordData *rd,
+						  const struct GNUNET_CRYPTO_RsaSignature *signature);
+
+
+/**
+ * Get a result for a particular key from the namestore.  The processor
+ * will only be called once.  
+ *
+ * @param h handle to the namestore
+ * @param zone zone to look up a record from
+ * @param name name to look up
+ * @param record_type desired record type, 0 for all
+ * @param proc function to call on the matching records, or with
+ *        NULL (rd_count == 0) if there are no matching records
+ * @param proc_cls closure for proc
+ * @return a handle that can be used to
+ *         cancel
+ */
+struct GNUNET_NAMESTORE_QueueEntry *
+GNUNET_NAMESTORE_lookup_record (struct GNUNET_NAMESTORE_Handle *h, 
+			      const GNUNET_HashCode *zone,
+			      const char *name,
+			      uint32_t record_type,
+			      GNUNET_NAMESTORE_RecordProcessor proc, void *proc_cls);
+
+
+/**
+ * Starts a new zone iteration (used to periodically PUT all of our
+ * records into our DHT). This MUST lock the GNUNET_NAMESTORE_Handle
+ * for any other calls than GNUNET_NAMESTORE_zone_iterator_next and
+ * GNUNET_NAMESTORE_zone_iteration_stop.  "proc" will be called once
+ * immediately, and then again after
+ * "GNUNET_NAMESTORE_zone_iterator_next" is invoked.
+ *
+ * @param h handle to the namestore
+ * @param zone zone to access, NULL for all zones
+ * @param must_have_flags flags that must be set for the record to be returned
+ * @param must_not_have_flags flags that must NOT be set for the record to be returned
+ * @param proc function to call on each name from the zone; it
+ *        will be called repeatedly with a value (if available)
+ *        and always once at the end with a name of NULL.
+ * @param proc_cls closure for proc
+ * @return an iterator handle to use for iteration
+ */
+struct GNUNET_NAMESTORE_ZoneIterator *
+GNUNET_NAMESTORE_zone_iteration_start (struct GNUNET_NAMESTORE_Handle *h,
+				       const GNUNET_HashCode *zone,
+				       enum GNUNET_NAMESTORE_RecordFlags must_have_flags,
+				       enum GNUNET_NAMESTORE_RecordFlags must_not_have_flags,
+				       GNUNET_NAMESTORE_RecordProcessor proc,
+				       void *proc_cls);
+
+
+/**
+ * Calls the record processor specified in GNUNET_NAMESTORE_zone_iteration_start
+ * for the next record.
+ *
+ * @param it the iterator
+ */
+void
+GNUNET_NAMESTORE_zone_iterator_next (struct GNUNET_NAMESTORE_ZoneIterator *it);
+
+
+/**
+ * Stops iteration and releases the namestore handle for further calls.
+ *
+ * @param it the iterator
+ */
+void
+GNUNET_NAMESTORE_zone_iteration_stop (struct GNUNET_NAMESTORE_ZoneIterator *it);
+
+
+/**
+ * Cancel a namestore operation.  The final callback from the
+ * operation must not have been done yet.
+ *
+ * @param qe operation to cancel
+ */
+void
+GNUNET_NAMESTORE_cancel (struct GNUNET_NAMESTORE_QueueEntry *qe);
+
+
+#if 0                           /* keep Emacsens' auto-indent happy */
+{
+#endif
+#ifdef __cplusplus
+}
+#endif
+
+/* end of gnunet_namestore_service.h */
+#endif