1 files changed, 429 insertions, 0 deletions

diff --git a/src/plugin/namecache/plugin_namecache_flat.c b/src/plugin/namecache/plugin_namecache_flat.c
new file mode 100644
index 000000000..ba118bf02
--- /dev/null
+++ b/src/plugin/namecache/plugin_namecache_flat.c
@@ -0,0 +1,429 @@
+/*
+ * This file is part of GNUnet
+ * Copyright (C) 2009-2015 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
+ */
+
+/**
+ * @file namecache/plugin_namecache_flat.c
+ * @brief flat file-based namecache backend
+ * @author Martin Schanzenbach
+ */
+
+#include "platform.h"
+#include "gnunet_namecache_plugin.h"
+#include "gnunet_namecache_service.h"
+#include "gnunet_gnsrecord_lib.h"
+
+/**
+ * Context for all functions in this plugin.
+ */
+struct Plugin
+{
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+  /**
+   * Database filename.
+   */
+  char *fn;
+
+  /**
+   * HashMap
+   */
+  struct GNUNET_CONTAINER_MultiHashMap *hm;
+};
+
+struct FlatFileEntry
+{
+  /**
+   * Block
+   */
+  struct GNUNET_GNSRECORD_Block *block;
+
+  /**
+   * query
+   */
+  struct GNUNET_HashCode query;
+};
+
+/**
+ * Initialize the database connections and associated
+ * data structures (create tables and indices
+ * as needed as well).
+ *
+ * @param plugin the plugin context (state for this module)
+ * @return #GNUNET_OK on success
+ */
+static int
+database_setup (struct Plugin *plugin)
+{
+  char *afsdir;
+  char*block_buffer;
+  char*buffer;
+  char*line;
+  char*query;
+  char*block;
+  uint64_t size;
+  struct FlatFileEntry *entry;
+  struct GNUNET_DISK_FileHandle *fh;
+
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_filename (plugin->cfg,
+                                               "namecache-flat",
+                                               "FILENAME",
+                                               &afsdir))
+  {
+    GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+                               "namecache-flat", "FILENAME");
+    return GNUNET_SYSERR;
+  }
+  if (GNUNET_OK != GNUNET_DISK_file_test (afsdir))
+  {
+    if (GNUNET_OK != GNUNET_DISK_directory_create_for_file (afsdir))
+    {
+      GNUNET_break (0);
+      GNUNET_free (afsdir);
+      return GNUNET_SYSERR;
+    }
+  }
+  /* afsdir should be UTF-8-encoded. If it isn't, it's a bug */
+  plugin->fn = afsdir;
+
+  /* Load data from file into hashmap */
+  plugin->hm = GNUNET_CONTAINER_multihashmap_create (10,
+                                                     GNUNET_NO);
+  fh = GNUNET_DISK_file_open (afsdir,
+                              GNUNET_DISK_OPEN_CREATE
+                              | GNUNET_DISK_OPEN_READWRITE,
+                              GNUNET_DISK_PERM_USER_WRITE
+                              | GNUNET_DISK_PERM_USER_READ);
+  if (NULL == fh)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("Unable to initialize file: %s.\n"),
+                afsdir);
+    return GNUNET_SYSERR;
+  }
+
+  if (GNUNET_SYSERR == GNUNET_DISK_file_size (afsdir,
+                                              &size,
+                                              GNUNET_YES,
+                                              GNUNET_YES))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("Unable to get filesize: %s.\n"),
+                afsdir);
+    GNUNET_DISK_file_close (fh);
+    return GNUNET_SYSERR;
+  }
+
+  if (0 == size)
+  {
+    GNUNET_DISK_file_close (fh);
+    return GNUNET_OK;
+  }
+
+  buffer = GNUNET_malloc (size + 1);
+
+  if (GNUNET_SYSERR == GNUNET_DISK_file_read (fh,
+                                              buffer,
+                                              size))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("Unable to read file: %s.\n"),
+                afsdir);
+    GNUNET_free (buffer);
+    GNUNET_DISK_file_close (fh);
+    return GNUNET_SYSERR;
+  }
+  buffer[size] = '\0';
+
+  GNUNET_DISK_file_close (fh);
+  if (0 < size)
+  {
+    line = strtok (buffer, "\n");
+    while (line != NULL)
+    {
+      query = strtok (line, ",");
+      if (NULL == query)
+        break;
+      block = strtok (NULL, ",");
+      if (NULL == block)
+        break;
+      line = strtok (NULL, "\n");
+      entry = GNUNET_malloc (sizeof(struct FlatFileEntry));
+      GNUNET_assert (GNUNET_OK == GNUNET_CRYPTO_hash_from_string (query,
+                                                                  &entry->query));
+      GNUNET_STRINGS_base64_decode (block,
+                                    strlen (block),
+                                    (void **) &block_buffer);
+      entry->block = (struct GNUNET_GNSRECORD_Block *) block_buffer;
+      if (GNUNET_OK !=
+          GNUNET_CONTAINER_multihashmap_put (plugin->hm,
+                                             &entry->query,
+                                             entry,
+                                             GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
+      {
+        GNUNET_free (entry);
+        GNUNET_break (0);
+      }
+    }
+  }
+  GNUNET_free (buffer);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Store values in hashmap in file and free data
+ *
+ * @param plugin the plugin context
+ */
+static int
+store_and_free_entries (void *cls,
+                        const struct GNUNET_HashCode *key,
+                        void *value)
+{
+  struct GNUNET_DISK_FileHandle *fh = cls;
+  struct FlatFileEntry *entry = value;
+
+  char *line;
+  char *block_b64;
+  struct GNUNET_CRYPTO_HashAsciiEncoded query;
+  size_t block_size;
+
+  block_size = GNUNET_GNSRECORD_block_get_size (entry->block);
+  GNUNET_STRINGS_base64_encode ((char *) entry->block,
+                                block_size,
+                                &block_b64);
+  GNUNET_CRYPTO_hash_to_enc (&entry->query,
+                             &query);
+  GNUNET_asprintf (&line,
+                   "%s,%s\n",
+                   (char *) &query,
+                   block_b64);
+
+  GNUNET_free (block_b64);
+
+  GNUNET_DISK_file_write (fh,
+                          line,
+                          strlen (line));
+
+  GNUNET_free (entry->block);
+  GNUNET_free (entry);
+  GNUNET_free (line);
+  return GNUNET_YES;
+}
+
+
+/**
+ * Shutdown database connection and associate data
+ * structures.
+ * @param plugin the plugin context (state for this module)
+ */
+static void
+database_shutdown (struct Plugin *plugin)
+{
+  struct GNUNET_DISK_FileHandle *fh;
+
+  fh = GNUNET_DISK_file_open (plugin->fn,
+                              GNUNET_DISK_OPEN_CREATE
+                              | GNUNET_DISK_OPEN_TRUNCATE
+                              | GNUNET_DISK_OPEN_READWRITE,
+                              GNUNET_DISK_PERM_USER_WRITE
+                              | GNUNET_DISK_PERM_USER_READ);
+  if (NULL == fh)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("Unable to initialize file: %s.\n"),
+                plugin->fn);
+    return;
+  }
+
+  GNUNET_CONTAINER_multihashmap_iterate (plugin->hm,
+                                         &store_and_free_entries,
+                                         fh);
+  GNUNET_CONTAINER_multihashmap_destroy (plugin->hm);
+  GNUNET_DISK_file_close (fh);
+}
+
+
+static int
+expire_blocks (void *cls,
+               const struct GNUNET_HashCode *key,
+               void *value)
+{
+  struct Plugin *plugin = cls;
+  struct FlatFileEntry *entry = value;
+  struct GNUNET_TIME_Absolute now;
+  struct GNUNET_TIME_Absolute expiration;
+
+  now = GNUNET_TIME_absolute_get ();
+  expiration = GNUNET_GNSRECORD_block_get_expiration (entry->block);
+
+  if (0 == GNUNET_TIME_absolute_get_difference (now,
+                                                expiration).rel_value_us)
+  {
+    GNUNET_CONTAINER_multihashmap_remove_all (plugin->hm, key);
+  }
+  return GNUNET_YES;
+}
+
+
+/**
+ * Removes any expired block.
+ *
+ * @param plugin the plugin
+ */
+static void
+namecache_expire_blocks (struct Plugin *plugin)
+{
+  GNUNET_CONTAINER_multihashmap_iterate (plugin->hm,
+                                         &expire_blocks,
+                                         plugin);
+}
+
+
+/**
+ * Cache a block in the datastore.
+ *
+ * @param cls closure (internal context for the plugin)
+ * @param block block to cache
+ * @return #GNUNET_OK on success, else #GNUNET_SYSERR
+ */
+static int
+namecache_cache_block (void *cls,
+                       const struct GNUNET_GNSRECORD_Block *block)
+{
+  struct Plugin *plugin = cls;
+  struct GNUNET_HashCode query;
+  struct FlatFileEntry *entry;
+  size_t block_size;
+
+  namecache_expire_blocks (plugin);
+  GNUNET_GNSRECORD_query_from_block (block,
+                                     &query);
+  block_size = GNUNET_GNSRECORD_block_get_size (block);
+  if (block_size > 64 * 65536)
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  entry = GNUNET_malloc (sizeof(struct FlatFileEntry));
+  entry->block = GNUNET_malloc (block_size);
+  GNUNET_memcpy (entry->block, block, block_size);
+  GNUNET_CONTAINER_multihashmap_remove_all (plugin->hm, &query);
+  if (GNUNET_OK !=
+      GNUNET_CONTAINER_multihashmap_put (plugin->hm,
+                                         &query,
+                                         entry,
+                                         GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
+  {
+    GNUNET_free (entry);
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Caching block under derived key `%s'\n",
+              GNUNET_h2s_full (&query));
+  return GNUNET_OK;
+}
+
+
+/**
+ * Get the block for a particular zone and label in the
+ * datastore.  Will return at most one result to the iterator.
+ *
+ * @param cls closure (internal context for the plugin)
+ * @param query hash of public key derived from the zone and the label
+ * @param iter function to call with the result
+ * @param iter_cls closure for @a iter
+ * @return #GNUNET_OK on success, #GNUNET_NO if there were no results, #GNUNET_SYSERR on error
+ */
+static int
+namecache_lookup_block (void *cls,
+                        const struct GNUNET_HashCode *query,
+                        GNUNET_NAMECACHE_BlockCallback iter, void *iter_cls)
+{
+  struct Plugin *plugin = cls;
+  const struct GNUNET_GNSRECORD_Block *block;
+
+  block = GNUNET_CONTAINER_multihashmap_get (plugin->hm, query);
+  if (NULL == block)
+    return GNUNET_NO;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Found block under derived key `%s'\n",
+              GNUNET_h2s_full (query));
+  iter (iter_cls, block);
+  return GNUNET_YES;
+}
+
+
+/**
+ * Entry point for the plugin.
+ *
+ * @param cls the "struct GNUNET_NAMECACHE_PluginEnvironment*"
+ * @return NULL on error, otherwise the plugin context
+ */
+void *
+libgnunet_plugin_namecache_flat_init (void *cls)
+{
+  static struct Plugin plugin;
+  const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
+  struct GNUNET_NAMECACHE_PluginFunctions *api;
+
+  if (NULL != plugin.cfg)
+    return NULL;                /* can only initialize once! */
+  memset (&plugin, 0, sizeof(struct Plugin));
+  plugin.cfg = cfg;
+  if (GNUNET_OK != database_setup (&plugin))
+  {
+    database_shutdown (&plugin);
+    return NULL;
+  }
+  api = GNUNET_new (struct GNUNET_NAMECACHE_PluginFunctions);
+  api->cls = &plugin;
+  api->cache_block = &namecache_cache_block;
+  api->lookup_block = &namecache_lookup_block;
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              _ ("flat plugin running\n"));
+  return api;
+}
+
+
+/**
+ * Exit point from the plugin.
+ *
+ * @param cls the plugin context (as returned by "init")
+ * @return always NULL
+ */
+void *
+libgnunet_plugin_namecache_flat_done (void *cls)
+{
+  struct GNUNET_NAMECACHE_PluginFunctions *api = cls;
+  struct Plugin *plugin = api->cls;
+
+  database_shutdown (plugin);
+  plugin->cfg = NULL;
+  GNUNET_free (api);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "flat plugin is finished\n");
+  return NULL;
+}
+
+
+/* end of plugin_namecache_sqlite.c */