-moving namestore_common functions to gnsrecord library

1 files changed, 188 insertions, 0 deletions

diff --git a/src/gnsrecord/gnsrecord_serialization.c b/src/gnsrecord/gnsrecord_serialization.c
new file mode 100644
index 000000000..0fd10b3e0
--- /dev/null
+++ b/src/gnsrecord/gnsrecord_serialization.c
@@ -0,0 +1,188 @@
+/*
+     This file is part of GNUnet.
+     (C) 2009-2013 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 gnsrecord/gnsrecord_serialization.c
+ * @brief API to serialize and deserialize GNS records
+ * @author Martin Schanzenbach
+ * @author Matthias Wachs
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_constants.h"
+#include "gnunet_signatures.h"
+#include "gnunet_arm_service.h"
+#include "gnunet_gnsrecord_lib.h"
+#include "gnunet_dnsparser_lib.h"
+#include "gnunet_tun_lib.h"
+
+
+#define LOG(kind,...) GNUNET_log_from (kind, "gnsrecord",__VA_ARGS__)
+
+GNUNET_NETWORK_STRUCT_BEGIN
+
+
+/**
+ * Internal format of a record in the serialized form.
+ */
+struct NetworkRecord
+{
+
+  /**
+   * Expiration time for the DNS record; relative or absolute depends
+   * on 'flags', network byte order.
+   */
+  uint64_t expiration_time GNUNET_PACKED;
+
+  /**
+   * Number of bytes in 'data', network byte order.
+   */
+  uint32_t data_size GNUNET_PACKED;
+
+  /**
+   * Type of the GNS/DNS record, network byte order.
+   */
+  uint32_t record_type GNUNET_PACKED;
+
+  /**
+   * Flags for the record, network byte order.
+   */
+  uint32_t flags GNUNET_PACKED;
+
+};
+
+GNUNET_NETWORK_STRUCT_END
+
+
+/**
+ * Calculate how many bytes we will need to serialize the given
+ * records.
+ *
+ * @param rd_count number of records in the rd array
+ * @param rd array of #GNUNET_NAMESTORE_RecordData with @a rd_count elements
+ * @return the required size to serialize
+ */
+size_t
+GNUNET_NAMESTORE_records_get_size (unsigned int rd_count,
+                                   const struct GNUNET_NAMESTORE_RecordData *rd)
+{
+  unsigned int i;
+  size_t ret;
+
+  ret = sizeof (struct NetworkRecord) * rd_count;
+  for (i=0;i<rd_count;i++)
+  {
+    GNUNET_assert ((ret + rd[i].data_size) >= ret);
+    ret += rd[i].data_size;
+  }
+  return ret;
+}
+
+
+/**
+ * Serialize the given records to the given destination buffer.
+ *
+ * @param rd_count number of records in the rd array
+ * @param rd array of #GNUNET_NAMESTORE_RecordData with @a rd_count elements
+ * @param dest_size size of the destination array
+ * @param dest where to write the result
+ * @return the size of serialized records, -1 if records do not fit
+ */
+ssize_t
+GNUNET_NAMESTORE_records_serialize (unsigned int rd_count,
+                                    const struct GNUNET_NAMESTORE_RecordData *rd,
+                                    size_t dest_size,
+                                    char *dest)
+{
+  struct NetworkRecord rec;
+  unsigned int i;
+  size_t off;
+
+  off = 0;
+  for (i=0;i<rd_count;i++)
+  {
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "Serializing record %u with flags %d and expiration time %llu\n",
+         i,
+         rd[i].flags,
+         (unsigned long long) rd[i].expiration_time);
+    rec.expiration_time = GNUNET_htonll (rd[i].expiration_time);
+    rec.data_size = htonl ((uint32_t) rd[i].data_size);
+    rec.record_type = htonl (rd[i].record_type);
+    rec.flags = htonl (rd[i].flags);
+    if (off + sizeof (rec) > dest_size)
+      return -1;
+    memcpy (&dest[off], &rec, sizeof (rec));
+    off += sizeof (rec);
+    if (off + rd[i].data_size > dest_size)
+      return -1;
+    memcpy (&dest[off], rd[i].data, rd[i].data_size);
+    off += rd[i].data_size;
+  }
+  return off;
+}
+
+
+/**
+ * Deserialize the given records to the given destination.
+ *
+ * @param len size of the serialized record data
+ * @param src the serialized record data
+ * @param rd_count number of records in the rd array
+ * @param dest where to put the data
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+int
+GNUNET_NAMESTORE_records_deserialize (size_t len,
+                                      const char *src,
+                                      unsigned int rd_count,
+                                      struct GNUNET_NAMESTORE_RecordData *dest)
+{
+  struct NetworkRecord rec;
+  unsigned int i;
+  size_t off;
+
+  off = 0;
+  for (i=0;i<rd_count;i++)
+  {
+    if (off + sizeof (rec) > len)
+      return GNUNET_SYSERR;
+    memcpy (&rec, &src[off], sizeof (rec));
+    dest[i].expiration_time = GNUNET_ntohll (rec.expiration_time);
+    dest[i].data_size = ntohl ((uint32_t) rec.data_size);
+    dest[i].record_type = ntohl (rec.record_type);
+    dest[i].flags = ntohl (rec.flags);
+    off += sizeof (rec);
+    if (off + dest[i].data_size > len)
+      return GNUNET_SYSERR;
+    dest[i].data = &src[off];
+    off += dest[i].data_size;
+    LOG (GNUNET_ERROR_TYPE_DEBUG,
+         "Deserialized record %u with flags %d and expiration time %llu\n",
+         i,
+         dest[i].flags,
+         (unsigned long long) dest[i].expiration_time);
+  }
+  return GNUNET_OK;
+}
+
+
+/* end of gnsrecord_serialization.c */