gnsrecord_misc.c

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/*
     This file is part of GNUnet.
     Copyright (C) 2009-2013 GNUnet e.V.

     GNUnet is free software: you can redistribute it and/or modify it
     under the terms of the GNU Affero General Public License as published
     by the Free Software Foundation, either version 3 of the License,
     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
     Affero General Public License for more details.
    
     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
*/

#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__)

char *
GNUNET_GNSRECORD_string_to_lowercase (const char *src)
{
  char *res;

  res = GNUNET_strdup (src);
  GNUNET_STRINGS_utf8_tolower (src, res);
  return res;
}


const char *
GNUNET_GNSRECORD_z2s (const struct GNUNET_CRYPTO_EcdsaPublicKey *z)
{
  static char buf[sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey) * 8];
  char *end;

  end = GNUNET_STRINGS_data_to_string ((const unsigned char *) z,
                                       sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey),
                                       buf, sizeof (buf));
  if (NULL == end)
  {
    GNUNET_break (0);
    return NULL;
  }
  *end = '\0';
  return buf;
}


int
GNUNET_GNSRECORD_records_cmp (const struct GNUNET_GNSRECORD_Data *a,
                              const struct GNUNET_GNSRECORD_Data *b)
{
  LOG (GNUNET_ERROR_TYPE_DEBUG,
       "Comparing records\n");
  if (a->record_type != b->record_type)
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG,
         "Record type %lu != %lu\n", a->record_type, b->record_type);
    return GNUNET_NO;
  }
  if ((a->expiration_time != b->expiration_time) &&
      ((a->expiration_time != 0) && (b->expiration_time != 0)))
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG,
         "Expiration time %llu != %llu\n",
         a->expiration_time,
         b->expiration_time);
    return GNUNET_NO;
  }
  if ((a->flags & GNUNET_GNSRECORD_RF_RCMP_FLAGS)
       != (b->flags & GNUNET_GNSRECORD_RF_RCMP_FLAGS))
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG,
         "Flags %lu (%lu) != %lu (%lu)\n", a->flags,
         a->flags & GNUNET_GNSRECORD_RF_RCMP_FLAGS, b->flags,
         b->flags & GNUNET_GNSRECORD_RF_RCMP_FLAGS);
    return GNUNET_NO;
  }
  if (a->data_size != b->data_size)
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG,
         "Data size %lu != %lu\n",
         a->data_size,
         b->data_size);
    return GNUNET_NO;
  }
  if (0 != memcmp (a->data, b->data, a->data_size))
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG,
         "Data contents do not match\n");
    return GNUNET_NO;
  }
  LOG (GNUNET_ERROR_TYPE_DEBUG,
       "Records are equal\n");
  return GNUNET_YES;
}


struct GNUNET_TIME_Absolute
GNUNET_GNSRECORD_record_get_expiration_time (unsigned int rd_count,
                                             const struct GNUNET_GNSRECORD_Data *rd)
{
  struct GNUNET_TIME_Absolute expire;
  struct GNUNET_TIME_Absolute at;
  struct GNUNET_TIME_Relative rt;
  struct GNUNET_TIME_Absolute at_shadow;
  struct GNUNET_TIME_Relative rt_shadow;

  if (NULL == rd)
    return GNUNET_TIME_UNIT_ZERO_ABS;
  expire = GNUNET_TIME_UNIT_FOREVER_ABS;
  for (unsigned int c = 0; c < rd_count; c++)
  {
    if (0 != (rd[c].flags & GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION))
    {
      rt.rel_value_us = rd[c].expiration_time;
      at = GNUNET_TIME_relative_to_absolute (rt);
    }
    else
    {
      at.abs_value_us = rd[c].expiration_time;
    }

    for (unsigned int c2 = 0; c2 < rd_count; c2++)
    {
      /* Check for shadow record */
      if ( (c == c2) ||
           (rd[c].record_type != rd[c2].record_type) ||
           (0 == (rd[c2].flags & GNUNET_GNSRECORD_RF_SHADOW_RECORD)) )
          continue;
      /* We have a shadow record */
      if (0 != (rd[c2].flags & GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION))
      {
        rt_shadow.rel_value_us = rd[c2].expiration_time;
        at_shadow = GNUNET_TIME_relative_to_absolute (rt_shadow);
      }
      else
      {
        at_shadow.abs_value_us = rd[c2].expiration_time;
      }
      at = GNUNET_TIME_absolute_max (at,
                                     at_shadow);
    }
    expire = GNUNET_TIME_absolute_min (at, 
                                       expire);
  }
  LOG (GNUNET_ERROR_TYPE_DEBUG,
       "Determined expiration time for block with %u records to be %s\n",
       rd_count,
       GNUNET_STRINGS_absolute_time_to_string (expire));
  return expire;
}


int
GNUNET_GNSRECORD_is_expired (const struct GNUNET_GNSRECORD_Data *rd)
{
  struct GNUNET_TIME_Absolute at;

  if (0 != (rd->flags & GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION))
    return GNUNET_NO;
  at.abs_value_us = rd->expiration_time;
  return (0 == GNUNET_TIME_absolute_get_remaining (at).rel_value_us) ? GNUNET_YES : GNUNET_NO;
}


const char *
GNUNET_GNSRECORD_pkey_to_zkey (const struct GNUNET_CRYPTO_EcdsaPublicKey *pkey)
{
  static char ret[128];
  char *pkeys;

  pkeys = GNUNET_CRYPTO_ecdsa_public_key_to_string (pkey);
  GNUNET_snprintf (ret,
                   sizeof (ret),
                   "%s",
                   pkeys);
  GNUNET_free (pkeys);
  return ret;
}


int
GNUNET_GNSRECORD_zkey_to_pkey (const char *zkey,
                               struct GNUNET_CRYPTO_EcdsaPublicKey *pkey)
{
  if (GNUNET_OK !=
      GNUNET_CRYPTO_ecdsa_public_key_from_string (zkey,
                                                  strlen (zkey),
                                                  pkey))
    return GNUNET_SYSERR;
  return GNUNET_OK;
}


/* end of gnsrecord_misc.c */