/*
This file is part of GNUnet.
Copyright (C) 2010-2014 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 .
SPDX-License-Identifier: AGPL3.0-or-later
*/
/**
* @file transport/gnunet-service-transport_plugins.c
* @brief plugin management
* @author Christian Grothoff
*/
#include "platform.h"
#include "gnunet-service-transport.h"
#include "gnunet-service-transport_hello.h"
#include "gnunet-service-transport_ats.h"
#include "gnunet-service-transport_plugins.h"
/**
* Entry in doubly-linked list of all of our plugins.
*/
struct TransportPlugin
{
/**
* This is a doubly-linked list.
*/
struct TransportPlugin *next;
/**
* This is a doubly-linked list.
*/
struct TransportPlugin *prev;
/**
* API of the transport as returned by the plugin's
* initialization function.
*/
struct GNUNET_TRANSPORT_PluginFunctions *api;
/**
* Short name for the plugin (e.g. "tcp").
*/
char *short_name;
/**
* Name of the library (e.g. "gnunet_plugin_transport_tcp").
*/
char *lib_name;
/**
* Environment this transport service is using
* for this plugin.
*/
struct GNUNET_TRANSPORT_PluginEnvironment env;
};
/**
* Head of DLL of all loaded plugins.
*/
static struct TransportPlugin *plugins_head;
/**
* Head of DLL of all loaded plugins.
*/
static struct TransportPlugin *plugins_tail;
/**
* Function that will be called to update metrics for an address
*
* @param cls closure
* @param address address to update metrics for
* @param session the session
* @param distance new distance
*/
static void
plugin_env_update_distance (void *cls,
const struct GNUNET_HELLO_Address *address,
uint32_t distance)
{
GST_ats_update_distance (address,
distance);
}
/**
* Function that will be called to figure if an address is an loopback,
* LAN, WAN etc. address
*
* @param cls closure
* @param addr binary address
* @param addrlen length of the @a addr
* @return type of the network @a addr belongs to
*/
static enum GNUNET_NetworkType
plugin_env_address_to_type (void *cls,
const struct sockaddr *addr,
size_t addrlen)
{
if (NULL == GST_is)
{
GNUNET_break (0);
return GNUNET_NT_UNSPECIFIED;
}
return GNUNET_NT_scanner_get_type (GST_is,
addr,
addrlen);
}
/**
* Load and initialize all plugins. The respective functions will be
* invoked by the plugins when the respective events happen. The
* closure will be set to a 'const char*' containing the name of the
* plugin that caused the call.
*
* @param recv_cb function to call when data is received
* @param address_cb function to call when our public addresses changed
* @param session_start_cb function to call when a session was created
* @param session_end_cb function to call when a session was terminated
* @param address_type_cb function to call when a address type is requested
*/
void
GST_plugins_load (GNUNET_TRANSPORT_PluginReceiveCallback recv_cb,
GNUNET_TRANSPORT_AddressNotification address_cb,
GNUNET_TRANSPORT_SessionStart session_start_cb,
GNUNET_TRANSPORT_SessionEnd session_end_cb)
{
struct TransportPlugin *plug;
struct TransportPlugin *next;
unsigned long long tneigh;
char *libname;
char *plugs;
char *pos;
int fail;
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_number (GST_cfg,
"TRANSPORT",
"NEIGHBOUR_LIMIT",
&tneigh))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Transport service is lacking NEIGHBOUR_LIMIT option.\n"));
return;
}
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_string (GST_cfg,
"TRANSPORT",
"PLUGINS",
&plugs))
return;
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
_ ("Starting transport plugins `%s'\n"),
plugs);
for (pos = strtok (plugs, " "); pos != NULL; pos = strtok (NULL, " "))
{
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
_ ("Loading `%s' transport plugin\n"),
pos);
GNUNET_asprintf (&libname,
"libgnunet_plugin_transport_%s",
pos);
plug = GNUNET_new (struct TransportPlugin);
plug->short_name = GNUNET_strdup (pos);
plug->lib_name = libname;
plug->env.cfg = GST_cfg;
plug->env.my_identity = &GST_my_identity;
plug->env.get_our_hello = &GST_hello_get;
plug->env.cls = plug->short_name;
plug->env.receive = recv_cb;
plug->env.notify_address = address_cb;
plug->env.session_start = session_start_cb;
plug->env.session_end = session_end_cb;
plug->env.get_address_type = &plugin_env_address_to_type;
plug->env.update_address_distance = &plugin_env_update_distance;
plug->env.max_connections = tneigh;
plug->env.stats = GST_stats;
GNUNET_CONTAINER_DLL_insert (plugins_head,
plugins_tail,
plug);
}
GNUNET_free (plugs);
next = plugins_head;
while (NULL != next)
{
plug = next;
next = plug->next;
plug->api = GNUNET_PLUGIN_load (plug->lib_name,
&plug->env);
if (NULL == plug->api)
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Failed to load transport plugin for `%s'\n"),
plug->lib_name);
GNUNET_CONTAINER_DLL_remove (plugins_head,
plugins_tail,
plug);
GNUNET_free (plug->short_name);
GNUNET_free (plug->lib_name);
GNUNET_free (plug);
continue;
}
fail = GNUNET_NO;
if (NULL == plug->api->address_pretty_printer)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"address_pretty_printer",
plug->lib_name);
}
if (NULL == plug->api->address_to_string)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"address_to_string",
plug->lib_name);
}
if (NULL == plug->api->string_to_address)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"string_to_address",
plug->lib_name);
}
if (NULL == plug->api->check_address)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"check_address",
plug->lib_name);
}
if (NULL == plug->api->get_session)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"get_session",
plug->lib_name);
}
if (NULL == plug->api->get_network)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"get_network",
plug->lib_name);
}
if (NULL == plug->api->send)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"send",
plug->lib_name);
}
if (NULL == plug->api->disconnect_peer)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"disconnect_peer",
plug->lib_name);
}
if (NULL == plug->api->disconnect_session)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"disconnect_session",
plug->lib_name);
}
if (NULL == plug->api->query_keepalive_factor)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"query_keepalive_factor",
plug->lib_name);
}
if (NULL == plug->api->update_session_timeout)
{
fail = GNUNET_YES;
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Missing function `%s' in transport plugin for `%s'\n"),
"update_session_timeout",
plug->lib_name);
}
if (GNUNET_YES == fail)
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
_ ("Did not load plugin `%s' due to missing functions\n"),
plug->lib_name);
GNUNET_break (NULL == GNUNET_PLUGIN_unload (plug->lib_name, plug->api));
GNUNET_CONTAINER_DLL_remove (plugins_head,
plugins_tail,
plug);
GNUNET_free (plug->short_name);
GNUNET_free (plug->lib_name);
GNUNET_free (plug);
}
}
}
/**
* Unload all plugins
*/
void
GST_plugins_unload ()
{
struct TransportPlugin *plug;
while (NULL != (plug = plugins_head))
{
GNUNET_break (NULL == GNUNET_PLUGIN_unload (plug->lib_name, plug->api));
GNUNET_free (plug->lib_name);
GNUNET_free (plug->short_name);
GNUNET_CONTAINER_DLL_remove (plugins_head, plugins_tail, plug);
GNUNET_free (plug);
}
}
/**
* Obtain the plugin API based on a plugin name.
*
* @param name name of the plugin
* @return the plugin's API, NULL if the plugin is not loaded
*/
struct GNUNET_TRANSPORT_PluginFunctions *
GST_plugins_find (const char *name)
{
struct TransportPlugin *pos;
for (pos = plugins_head; NULL != pos; pos = pos->next)
if (0 == strcmp (name, pos->short_name))
break;
if (NULL == pos)
return NULL;
return pos->api;
}
/**
* Obtain the plugin API based on a the stripped plugin name after the underscore.
*
* Example: GST_plugins_printer_find (http_client) will return all plugins
* starting with the prefix "http":
* http_client or server if loaded
*
* @param name name of the plugin
* @return the plugin's API, NULL if the plugin is not loaded
*/
struct GNUNET_TRANSPORT_PluginFunctions *
GST_plugins_printer_find (const char *name)
{
struct TransportPlugin *pos;
char *stripped = GNUNET_strdup (name);
char *sep = strchr (stripped, '_');
if (NULL != sep)
sep[0] = '\0';
for (pos = plugins_head; NULL != pos; pos = pos->next)
if (pos->short_name == strstr (pos->short_name, stripped))
break;
GNUNET_free (stripped);
if (NULL == pos)
return NULL;
return pos->api;
}
/**
* Convert a given address to a human-readable format. Note that the
* return value will be overwritten on the next call to this function.
*
* @param address the address to convert
* @return statically allocated (!) human-readable address
*/
const char *
GST_plugins_a2s (const struct GNUNET_HELLO_Address *address)
{
struct GNUNET_TRANSPORT_PluginFunctions *api;
static char unable_to_show[1024];
static const char *s;
if (NULL == address)
return "";
if (0 == address->address_length)
return TRANSPORT_SESSION_INBOUND_STRING; /* Addresse with length 0 are inbound, address->address itself may be NULL */
api = GST_plugins_printer_find (address->transport_name);
if (NULL == api)
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"Failed to find transport plugin `%s'\n",
address->transport_name);
return "";
}
if (0 == address->address_length)
{
GNUNET_snprintf (unable_to_show,
sizeof(unable_to_show),
"",
(unsigned int) address->address_length,
address->transport_name);
return unable_to_show;
}
return(NULL != (s = api->address_to_string (NULL,
address->address,
address->address_length))
? s
: "");
}
/**
* Register callback with all plugins to monitor their status.
*
* @param cb callback to register, NULL to unsubscribe
* @param cb_cls closure for @a cb
*/
void
GST_plugins_monitor_subscribe (GNUNET_TRANSPORT_SessionInfoCallback cb,
void *cb_cls)
{
struct TransportPlugin *pos;
for (pos = plugins_head; NULL != pos; pos = pos->next)
if (NULL == pos->api->setup_monitor)
GNUNET_break (0);
else
pos->api->setup_monitor (pos->api->cls,
cb,
cb_cls);
}
/* end of file gnunet-service-transport_plugins.c */