GNUnet  0.11.x
gnunet-service-transport_plugins.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2010-2014 GNUnet e.V.
4 
5  GNUnet is free software: you can redistribute it and/or modify it
6  under the terms of the GNU Affero General Public License as published
7  by the Free Software Foundation, either version 3 of the License,
8  or (at your option) any later version.
9 
10  GNUnet is distributed in the hope that it will be useful, but
11  WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  Affero General Public License for more details.
14 
15  You should have received a copy of the GNU Affero General Public License
16  along with this program. If not, see <http://www.gnu.org/licenses/>.
17 
18  SPDX-License-Identifier: AGPL3.0-or-later
19  */
20 
26 #include "platform.h"
31 
35 struct TransportPlugin
36 {
40  struct TransportPlugin *next;
41 
45  struct TransportPlugin *prev;
46 
52 
56  char *short_name;
57 
61  char *lib_name;
62 
68 };
69 
74 
79 
80 
89 static void
91  const struct GNUNET_HELLO_Address *address,
92  uint32_t distance)
93 {
94  GST_ats_update_distance (address,
95  distance);
96 }
97 
98 
108 static enum GNUNET_NetworkType
110  const struct sockaddr *addr,
111  size_t addrlen)
112 {
113  if (NULL == GST_is)
114  {
115  GNUNET_break (0);
116  return GNUNET_NT_UNSPECIFIED;
117  }
119  addr,
120  addrlen);
121 }
122 
123 
136 void
139  GNUNET_TRANSPORT_SessionStart session_start_cb,
140  GNUNET_TRANSPORT_SessionEnd session_end_cb)
141 {
142  struct TransportPlugin *plug;
143  struct TransportPlugin *next;
144  unsigned long long tneigh;
145  char *libname;
146  char *plugs;
147  char *pos;
148  int fail;
149 
150  if (GNUNET_OK !=
152  "TRANSPORT",
153  "NEIGHBOUR_LIMIT",
154  &tneigh))
155  {
157  _ ("Transport service is lacking NEIGHBOUR_LIMIT option.\n"));
158  return;
159  }
160  if (GNUNET_OK !=
162  "TRANSPORT",
163  "PLUGINS",
164  &plugs))
165  return;
167  _ ("Starting transport plugins `%s'\n"),
168  plugs);
169  for (pos = strtok (plugs, " "); pos != NULL; pos = strtok (NULL, " "))
170  {
172  _ ("Loading `%s' transport plugin\n"),
173  pos);
174  GNUNET_asprintf (&libname,
175  "libgnunet_plugin_transport_%s",
176  pos);
177  plug = GNUNET_new (struct TransportPlugin);
178  plug->short_name = GNUNET_strdup (pos);
179  plug->lib_name = libname;
180  plug->env.cfg = GST_cfg;
183  plug->env.cls = plug->short_name;
184  plug->env.receive = recv_cb;
185  plug->env.notify_address = address_cb;
186  plug->env.session_start = session_start_cb;
187  plug->env.session_end = session_end_cb;
190  plug->env.max_connections = tneigh;
191  plug->env.stats = GST_stats;
192  GNUNET_CONTAINER_DLL_insert (plugins_head,
193  plugins_tail,
194  plug);
195  }
196  GNUNET_free (plugs);
197  next = plugins_head;
198  while (NULL != next)
199  {
200  plug = next;
201  next = plug->next;
202  plug->api = GNUNET_PLUGIN_load (plug->lib_name,
203  &plug->env);
204  if (NULL == plug->api)
205  {
207  _ ("Failed to load transport plugin for `%s'\n"),
208  plug->lib_name);
209  GNUNET_CONTAINER_DLL_remove (plugins_head,
210  plugins_tail,
211  plug);
212  GNUNET_free (plug->short_name);
213  GNUNET_free (plug->lib_name);
214  GNUNET_free (plug);
215  continue;
216  }
217  fail = GNUNET_NO;
218  if (NULL == plug->api->address_pretty_printer)
219  {
220  fail = GNUNET_YES;
222  _ ("Missing function `%s' in transport plugin for `%s'\n"),
223  "address_pretty_printer",
224  plug->lib_name);
225  }
226  if (NULL == plug->api->address_to_string)
227  {
228  fail = GNUNET_YES;
230  _ ("Missing function `%s' in transport plugin for `%s'\n"),
231  "address_to_string",
232  plug->lib_name);
233  }
234  if (NULL == plug->api->string_to_address)
235  {
236  fail = GNUNET_YES;
238  _ ("Missing function `%s' in transport plugin for `%s'\n"),
239  "string_to_address",
240  plug->lib_name);
241  }
242  if (NULL == plug->api->check_address)
243  {
244  fail = GNUNET_YES;
246  _ ("Missing function `%s' in transport plugin for `%s'\n"),
247  "check_address",
248  plug->lib_name);
249  }
250  if (NULL == plug->api->get_session)
251  {
252  fail = GNUNET_YES;
254  _ ("Missing function `%s' in transport plugin for `%s'\n"),
255  "get_session",
256  plug->lib_name);
257  }
258  if (NULL == plug->api->get_network)
259  {
260  fail = GNUNET_YES;
262  _ ("Missing function `%s' in transport plugin for `%s'\n"),
263  "get_network",
264  plug->lib_name);
265  }
266  if (NULL == plug->api->send)
267  {
268  fail = GNUNET_YES;
270  _ ("Missing function `%s' in transport plugin for `%s'\n"),
271  "send",
272  plug->lib_name);
273  }
274  if (NULL == plug->api->disconnect_peer)
275  {
276  fail = GNUNET_YES;
278  _ ("Missing function `%s' in transport plugin for `%s'\n"),
279  "disconnect_peer",
280  plug->lib_name);
281  }
282  if (NULL == plug->api->disconnect_session)
283  {
284  fail = GNUNET_YES;
286  _ ("Missing function `%s' in transport plugin for `%s'\n"),
287  "disconnect_session",
288  plug->lib_name);
289  }
290  if (NULL == plug->api->query_keepalive_factor)
291  {
292  fail = GNUNET_YES;
294  _ ("Missing function `%s' in transport plugin for `%s'\n"),
295  "query_keepalive_factor",
296  plug->lib_name);
297  }
298  if (NULL == plug->api->update_session_timeout)
299  {
300  fail = GNUNET_YES;
302  _ ("Missing function `%s' in transport plugin for `%s'\n"),
303  "update_session_timeout",
304  plug->lib_name);
305  }
306  if (GNUNET_YES == fail)
307  {
309  _ ("Did not load plugin `%s' due to missing functions\n"),
310  plug->lib_name);
311  GNUNET_break (NULL == GNUNET_PLUGIN_unload (plug->lib_name, plug->api));
312  GNUNET_CONTAINER_DLL_remove (plugins_head,
313  plugins_tail,
314  plug);
315  GNUNET_free (plug->short_name);
316  GNUNET_free (plug->lib_name);
317  GNUNET_free (plug);
318  }
319  }
320 }
321 
322 
326 void
328 {
329  struct TransportPlugin *plug;
330 
331  while (NULL != (plug = plugins_head))
332  {
333  GNUNET_break (NULL == GNUNET_PLUGIN_unload (plug->lib_name, plug->api));
334  GNUNET_free (plug->lib_name);
335  GNUNET_free (plug->short_name);
336  GNUNET_CONTAINER_DLL_remove (plugins_head, plugins_tail, plug);
337  GNUNET_free (plug);
338  }
339 }
340 
341 
349 GST_plugins_find (const char *name)
350 {
351  struct TransportPlugin *pos;
352 
353  for (pos = plugins_head; NULL != pos; pos = pos->next)
354  if (0 == strcmp (name, pos->short_name))
355  break;
356  if (NULL == pos)
357  return NULL;
358  return pos->api;
359 }
360 
361 
374 {
375  struct TransportPlugin *pos;
376  char *stripped = GNUNET_strdup (name);
377  char *sep = strchr (stripped, '_');
378 
379  if (NULL != sep)
380  sep[0] = '\0';
381  for (pos = plugins_head; NULL != pos; pos = pos->next)
382  if (pos->short_name == strstr (pos->short_name, stripped))
383  break;
384  GNUNET_free (stripped);
385  if (NULL == pos)
386  return NULL;
387  return pos->api;
388 }
389 
390 
398 const char *
400 {
402  static char unable_to_show[1024];
403  static const char *s;
404 
405  if (NULL == address)
406  return "<NULL>";
407  if (0 == address->address_length)
408  return TRANSPORT_SESSION_INBOUND_STRING; /* Addresse with length 0 are inbound, address->address itself may be NULL */
409  api = GST_plugins_printer_find (address->transport_name);
410  if (NULL == api)
411  {
413  "Failed to find transport plugin `%s'\n",
414  address->transport_name);
415  return "<plugin unknown>";
416  }
417  if (0 == address->address_length)
418  {
419  GNUNET_snprintf (unable_to_show,
420  sizeof(unable_to_show),
421  "<unable to stringify %u-byte long address of %s transport>",
422  (unsigned int) address->address_length,
423  address->transport_name);
424  return unable_to_show;
425  }
426  return(NULL != (s = api->address_to_string (NULL,
427  address->address,
428  address->address_length))
429  ? s
430  : "<invalid>");
431 }
432 
433 
440 void
442  void *cb_cls)
443 {
444  struct TransportPlugin *pos;
445 
446  for (pos = plugins_head; NULL != pos; pos = pos->next)
447  if (NULL == pos->api->setup_monitor)
448  GNUNET_break (0);
449  else
450  pos->api->setup_monitor (pos->api->cls,
451  cb,
452  cb_cls);
453 }
454 
455 
456 /* end of file gnunet-service-transport_plugins.c */
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
static struct GNUNET_PeerIdentity GST_my_identity
Our public key.
size_t address_length
Number of bytes in address.
void(* GNUNET_TRANSPORT_SessionEnd)(void *cls, const struct GNUNET_HELLO_Address *address, struct GNUNET_ATS_Session *session)
Function that will be called whenever the plugin internally cleans up a session pointer and hence the...
enum GNUNET_NetworkType GNUNET_NT_scanner_get_type(struct GNUNET_NT_InterfaceScanner *is, const struct sockaddr *addr, socklen_t addrlen)
Returns where the address is located: loopback, LAN or WAN.
Definition: nt.c:314
char * short_name
Short name for the plugin (i.e.
GNUNET_TRANSPORT_CreateSession get_session
Function that will be called tell the plugin to create a session object.
struct TransportPlugin * prev
This is a doubly-linked list.
GNUNET_TRANSPORT_AddressToString address_to_string
Function that will be called to convert a binary address to a string (numeric conversion only)...
int GNUNET_CONFIGURATION_get_value_number(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, unsigned long long *number)
Get a configuration value that should be a number.
const void * address
Binary representation of the address (plugin-specific).
void(* GNUNET_TRANSPORT_AddressNotification)(void *cls, int add_remove, const struct GNUNET_HELLO_Address *address)
Function that will be called for each address the transport is aware that it might be reachable under...
#define GNUNET_CONTAINER_DLL_insert(head, tail, element)
Insert an element at the head of a DLL.
void GST_plugins_monitor_subscribe(GNUNET_TRANSPORT_SessionInfoCallback cb, void *cb_cls)
Register callback with all plugins to monitor their status.
GNUNET_TRANSPORT_SessionStart session_start
Function called by the plugin when a new (incoming) session was created not explicitly created using ...
struct TransportPlugin * next
This is a doubly-linked list.
int GNUNET_snprintf(char *buf, size_t size, const char *format,...)
Like snprintf, just aborts if the buffer is of insufficient size.
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)
Load and initialize all plugins.
void GST_ats_update_distance(const struct GNUNET_HELLO_Address *address, uint32_t distance)
Notify ATS about DV distance change to an address.
GNUNET_TRANSPORT_TransmitFunction send
Function that the transport service will use to transmit data to another peer.
GNUNET_TRANSPORT_DisconnectPeerFunction disconnect_peer
Function that can be used to force the plugin to disconnect from the given peer and cancel all previo...
GNUNET_TRANSPORT_AddressToType get_address_type
Function that will be called to figure if an address is an loopback, LAN, WAN etc.
GNUNET_TRANSPORT_DisconnectSessionFunction disconnect_session
Function that can be used to force the plugin to disconnect from the given peer and cancel all previo...
Each plugin is required to return a pointer to a struct of this type as the return value from its ent...
GNUNET_TRANSPORT_SessionMonitorSetup setup_monitor
Function to monitor the sessions managed by the plugin.
const struct GNUNET_PeerIdentity * my_identity
Identity of this peer.
interfacing between transport and ATS service
#define TRANSPORT_SESSION_INBOUND_STRING
#define GNUNET_NO
Definition: gnunet_common.h:78
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
#define GNUNET_new(type)
Allocate a struct or union of the given type.
static enum GNUNET_NetworkType plugin_env_address_to_type(void *cls, const struct sockaddr *addr, size_t addrlen)
Function that will be called to figure if an address is an loopback, LAN, WAN etc.
struct GNUNET_TRANSPORT_PluginFunctions * GST_plugins_printer_find(const char *name)
Obtain the plugin API based on a the stripped plugin name after the underscore.
uint32_t max_connections
What is the maximum number of connections that this transport should allow? Transports that do not ha...
#define GNUNET_strdup(a)
Wrapper around GNUNET_xstrdup_.
GNUNET_NetworkType
Types of networks (with separate quotas) we support.
Definition: gnunet_nt_lib.h:35
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
static void plugin_env_update_distance(void *cls, const struct GNUNET_HELLO_Address *address, uint32_t distance)
Function that will be called to update metrics for an address.
#define _(String)
GNU gettext support macro.
Definition: platform.h:181
void * GNUNET_PLUGIN_unload(const char *library_name, void *arg)
Unload plugin (runs the "done" callback and returns whatever "done" returned).
Definition: plugin.c:256
static void address_cb(void *cls, void **app_ctx, int add_remove, enum GNUNET_NAT_AddressClass ac, const struct sockaddr *addr, socklen_t addrlen)
Signature of the callback passed to GNUNET_NAT_register() for a function to call whenever our set of ...
Definition: gnunet-nat.c:122
GNUNET_TRANSPORT_SessionEnd session_end
Function that must be called by the plugin when a non-NULL session handle stops being valid (is destr...
GNUNET_TRANSPORT_PluginReceiveCallback receive
Function that should be called by the transport plugin whenever a message is received.
GNUNET_TRANSPORT_UpdateSessionTimeout update_session_timeout
Function that will be called whenever the transport service wants to notify the plugin that a session...
struct GNUNET_NT_InterfaceScanner * GST_is
Interface scanner determines our LAN address range(s).
int GNUNET_asprintf(char **buf, const char *format,...)
Like asprintf, just portable.
static struct GNUNET_STATISTICS_Handle * GST_stats
Statistics handle.
void * cls
Closure for the various callbacks.
void * cls
Closure for all of the callbacks.
static struct TransportPlugin * plugins_head
Head of DLL of all loaded plugins.
GNUNET_TRANSPORT_GetHelloCallback get_our_hello
Function that returns our HELLO.
GNUNET_TRANSPORT_StringToAddress string_to_address
Function that will be called to convert a string address to binary (numeric conversion only)...
struct GNUNET_TRANSPORT_PluginEnvironment env
Environment this transport service is using for this plugin.
The transport service will pass a pointer to a struct of this type as the first and only argument to ...
GNUNET_TRANSPORT_GetNetworkType get_network
Function to obtain the network type for a session.
struct GNUNET_TIME_Relative(* GNUNET_TRANSPORT_PluginReceiveCallback)(void *cls, const struct GNUNET_HELLO_Address *address, struct GNUNET_ATS_Session *session, const struct GNUNET_MessageHeader *message)
Function called by the transport for each received message.
const char * transport_name
Name of the transport plugin enabling the communication using this address.
static struct TransportPlugin * plugins_tail
Head of DLL of all loaded plugins.
void(* GNUNET_TRANSPORT_SessionInfoCallback)(void *cls, struct GNUNET_ATS_Session *session, const struct GNUNET_TRANSPORT_SessionInfo *info)
Function called by the plugin with information about the current sessions managed by the plugin (for ...
const char * GST_plugins_a2s(const struct GNUNET_HELLO_Address *address)
Convert a given address to a human-readable format.
struct GNUNET_TRANSPORT_PluginFunctions * GST_plugins_find(const char *name)
Obtain the plugin API based on a plugin name.
int GNUNET_CONFIGURATION_get_value_string(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, char **value)
Get a configuration value that should be a string.
char * lib_name
Name of the library (i.e.
GNUNET_TRANSPORT_UpdateAddressDistance update_address_distance
Function that will be called by DV to update distance for an address.
const struct GNUNET_CONFIGURATION_Handle * cfg
Configuration to use.
const struct GNUNET_MessageHeader * GST_hello_get()
Obtain this peers HELLO message.
GNUNET_TRANSPORT_QueryKeepaliveFactorFunction query_keepalive_factor
Function that is used to query keepalive factor.
Entry in doubly-linked list of all of our plugins.
struct GNUNET_TRANSPORT_PluginFunctions * api
API of the transport as returned by the plugin&#39;s initialization function.
void GST_plugins_unload()
Unload all plugins.
const char * name
An address for communicating with a peer.
struct GNUNET_STATISTICS_Handle * stats
Handle for reporting statistics.
#define GNUNET_log(kind,...)
GNUNET_TRANSPORT_AddressNotification notify_address
Function that must be called by each plugin to notify the transport service about the addresses under...
GNUNET_TRANSPORT_AddressPrettyPrinter address_pretty_printer
Function to pretty-print addresses.
#define GNUNET_YES
Definition: gnunet_common.h:77
static const struct GNUNET_CONFIGURATION_Handle * GST_cfg
Configuration handle.
void * GNUNET_PLUGIN_load(const char *library_name, void *arg)
Setup plugin (runs the "init" callback and returns whatever "init" returned).
Definition: plugin.c:207
void(* GNUNET_TRANSPORT_SessionStart)(void *cls, const struct GNUNET_HELLO_Address *address, struct GNUNET_ATS_Session *session, enum GNUNET_NetworkType net)
Plugin tells transport service about a new inbound session.
GNUNET_TRANSPORT_CheckAddress check_address
Function that will be called to check if a binary address for this plugin is well-formed and correspo...
static char * address
GNS address for this phone.
#define GNUNET_free(ptr)
Wrapper around free.
Category of last resort.
Definition: gnunet_nt_lib.h:40