diff options
Diffstat (limited to 'src/transport/tcp_server_legacy.c')
| -rw-r--r-- | src/transport/tcp_server_legacy.c | 1748 |
1 files changed, 1748 insertions, 0 deletions
diff --git a/src/transport/tcp_server_legacy.c b/src/transport/tcp_server_legacy.c new file mode 100644 index 000000000..c055285b1 --- /dev/null +++ b/src/transport/tcp_server_legacy.c @@ -0,0 +1,1748 @@ +/* + 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 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., 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301, USA. +*/ + +/** + * @file util/server.c + * @brief library for building GNUnet network servers + * @author Christian Grothoff + */ + +#include "platform.h" +#include "gnunet_util_lib.h" +#include "gnunet_protocols.h" + +#define LOG_STRERROR_FILE(kind,syscall,filename) GNUNET_log_from_strerror_file (kind, "util-server", syscall, filename) + + +/** + * List of arrays of message handlers. + */ +struct HandlerList +{ + /** + * This is a linked list. + */ + struct HandlerList *next; + + /** + * NULL-terminated array of handlers. + */ + const struct GNUNET_SERVER_MessageHandler *handlers; +}; + + +/** + * List of arrays of message handlers. + */ +struct NotifyList +{ + /** + * This is a doubly linked list. + */ + struct NotifyList *next; + + /** + * This is a doubly linked list. + */ + struct NotifyList *prev; + + /** + * Function to call. + */ + GNUNET_SERVER_DisconnectCallback callback; + + /** + * Closure for callback. + */ + void *callback_cls; +}; + + +/** + * @brief handle for a server + */ +struct GNUNET_SERVER_Handle +{ + /** + * List of handlers for incoming messages. + */ + struct HandlerList *handlers; + + /** + * Head of list of our current clients. + */ + struct GNUNET_SERVER_Client *clients_head; + + /** + * Head of list of our current clients. + */ + struct GNUNET_SERVER_Client *clients_tail; + + /** + * Head of linked list of functions to call on disconnects by clients. + */ + struct NotifyList *disconnect_notify_list_head; + + /** + * Tail of linked list of functions to call on disconnects by clients. + */ + struct NotifyList *disconnect_notify_list_tail; + + /** + * Head of linked list of functions to call on connects by clients. + */ + struct NotifyList *connect_notify_list_head; + + /** + * Tail of linked list of functions to call on connects by clients. + */ + struct NotifyList *connect_notify_list_tail; + + /** + * Function to call for access control. + */ + GNUNET_CONNECTION_AccessCheck access_cb; + + /** + * Closure for @e access_cb. + */ + void *access_cb_cls; + + /** + * NULL-terminated array of sockets used to listen for new + * connections. + */ + struct GNUNET_NETWORK_Handle **listen_sockets; + + /** + * After how long should an idle connection time + * out (on write). + */ + struct GNUNET_TIME_Relative idle_timeout; + + /** + * Task scheduled to do the listening. + */ + struct GNUNET_SCHEDULER_Task * listen_task; + + /** + * Alternative function to create a MST instance. + */ + GNUNET_SERVER_MstCreateCallback mst_create; + + /** + * Alternative function to destroy a MST instance. + */ + GNUNET_SERVER_MstDestroyCallback mst_destroy; + + /** + * Alternative function to give data to a MST instance. + */ + GNUNET_SERVER_MstReceiveCallback mst_receive; + + /** + * Closure for 'mst_'-callbacks. + */ + void *mst_cls; + + /** + * Do we ignore messages of types that we do not understand or do we + * require that a handler is found (and if not kill the connection)? + */ + int require_found; + + /** + * Set to #GNUNET_YES once we are in 'soft' shutdown where we wait for + * all non-monitor clients to disconnect before we call + * #GNUNET_SERVER_destroy. See test_monitor_clients(). Set to + * #GNUNET_SYSERR once the final destroy task has been scheduled + * (we cannot run it in the same task). + */ + int in_soft_shutdown; +}; + + +/** + * Handle server returns for aborting transmission to a client. + */ +struct GNUNET_SERVER_TransmitHandle +{ + /** + * Function to call to get the message. + */ + GNUNET_CONNECTION_TransmitReadyNotify callback; + + /** + * Closure for @e callback + */ + void *callback_cls; + + /** + * Active connection transmission handle. + */ + struct GNUNET_CONNECTION_TransmitHandle *cth; + +}; + + +/** + * @brief handle for a client of the server + */ +struct GNUNET_SERVER_Client +{ + + /** + * This is a doubly linked list. + */ + struct GNUNET_SERVER_Client *next; + + /** + * This is a doubly linked list. + */ + struct GNUNET_SERVER_Client *prev; + + /** + * Processing of incoming data. + */ + void *mst; + + /** + * Server that this client belongs to. + */ + struct GNUNET_SERVER_Handle *server; + + /** + * Client closure for callbacks. + */ + struct GNUNET_CONNECTION_Handle *connection; + + /** + * User context value, manipulated using + * 'GNUNET_SERVER_client_{get/set}_user_context' functions. + */ + void *user_context; + + /** + * ID of task used to restart processing. + */ + struct GNUNET_SCHEDULER_Task * restart_task; + + /** + * Task that warns about missing calls to #GNUNET_SERVER_receive_done. + */ + struct GNUNET_SCHEDULER_Task * warn_task; + + /** + * Time when the warn task was started. + */ + struct GNUNET_TIME_Absolute warn_start; + + /** + * Last activity on this socket (used to time it out + * if reference_count == 0). + */ + struct GNUNET_TIME_Absolute last_activity; + + /** + * Transmission handle we return for this client from + * #GNUNET_SERVER_notify_transmit_ready. + */ + struct GNUNET_SERVER_TransmitHandle th; + + /** + * After how long should an idle connection time + * out (on write). + */ + struct GNUNET_TIME_Relative idle_timeout; + + /** + * Number of external entities with a reference to + * this client object. + */ + unsigned int reference_count; + + /** + * Was processing if incoming messages suspended while + * we were still processing data already received? + * This is a counter saying how often processing was + * suspended (once per handler invoked). + */ + unsigned int suspended; + + /** + * Last size given when user context was initialized; used for + * sanity check. + */ + size_t user_context_size; + + /** + * Are we currently in the "process_client_buffer" function (and + * will hence restart the receive job on exit if suspended == 0 once + * we are done?). If this is set, then "receive_done" will + * essentially only decrement suspended; if this is not set, then + * "receive_done" may need to restart the receive process (either + * from the side-buffer or via select/recv). + */ + int in_process_client_buffer; + + /** + * We're about to close down this client. + */ + int shutdown_now; + + /** + * Are we currently trying to receive? (#GNUNET_YES if we are, + * #GNUNET_NO if we are not, #GNUNET_SYSERR if data is already + * available in MST). + */ + int receive_pending; + + /** + * Persist the file handle for this client no matter what happens, + * force the OS to close once the process actually dies. Should only + * be used in special cases! + */ + int persist; + + /** + * Is this client a 'monitor' client that should not be counted + * when deciding on destroying the server during soft shutdown? + * (see also #GNUNET_SERVICE_start) + */ + int is_monitor; + + /** + * Type of last message processed (for warn_no_receive_done). + */ + uint16_t warn_type; +}; + + + +/** + * Return user context associated with the given client. + * Note: you should probably use the macro (call without the underscore). + * + * @param client client to query + * @param size number of bytes in user context struct (for verification only) + * @return pointer to user context + */ +void * +GNUNET_SERVER_client_get_user_context_ (struct GNUNET_SERVER_Client *client, + size_t size) +{ + if ((0 == client->user_context_size) && + (NULL == client->user_context)) + return NULL; /* never set */ + GNUNET_assert (size == client->user_context_size); + return client->user_context; +} + + +/** + * Set user context to be associated with the given client. + * Note: you should probably use the macro (call without the underscore). + * + * @param client client to query + * @param ptr pointer to user context + * @param size number of bytes in user context struct (for verification only) + */ +void +GNUNET_SERVER_client_set_user_context_ (struct GNUNET_SERVER_Client *client, + void *ptr, + size_t size) +{ + if (NULL == ptr) + { + client->user_context_size = 0; + client->user_context = ptr; + return; + } + client->user_context_size = size; + client->user_context = ptr; +} + + +/** + * Scheduler says our listen socket is ready. Process it! + * + * @param cls handle to our server for which we are processing the listen + * socket + */ +static void +process_listen_socket (void *cls) +{ + struct GNUNET_SERVER_Handle *server = cls; + const struct GNUNET_SCHEDULER_TaskContext *tc; + struct GNUNET_CONNECTION_Handle *sock; + unsigned int i; + + server->listen_task = NULL; + tc = GNUNET_SCHEDULER_get_task_context (); + for (i = 0; NULL != server->listen_sockets[i]; i++) + { + if (GNUNET_NETWORK_fdset_isset (tc->read_ready, + server->listen_sockets[i])) + { + sock = + GNUNET_CONNECTION_create_from_accept (server->access_cb, + server->access_cb_cls, + server->listen_sockets[i]); + if (NULL != sock) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server accepted incoming connection.\n"); + (void) GNUNET_SERVER_connect_socket (server, + sock); + } + } + } + /* listen for more! */ + GNUNET_SERVER_resume (server); +} + + +/** + * Create and initialize a listen socket for the server. + * + * @param server_addr address to listen on + * @param socklen length of @a server_addr + * @return NULL on error, otherwise the listen socket + */ +static struct GNUNET_NETWORK_Handle * +open_listen_socket (const struct sockaddr *server_addr, + socklen_t socklen) +{ + struct GNUNET_NETWORK_Handle *sock; + uint16_t port; + int eno; + + switch (server_addr->sa_family) + { + case AF_INET: + port = ntohs (((const struct sockaddr_in *) server_addr)->sin_port); + break; + case AF_INET6: + port = ntohs (((const struct sockaddr_in6 *) server_addr)->sin6_port); + break; + case AF_UNIX: + port = 0; + break; + default: + GNUNET_break (0); + port = 0; + break; + } + sock = GNUNET_NETWORK_socket_create (server_addr->sa_family, SOCK_STREAM, 0); + if (NULL == sock) + { + LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "socket"); + errno = 0; + return NULL; + } + /* bind the socket */ + if (GNUNET_OK != GNUNET_NETWORK_socket_bind (sock, server_addr, socklen)) + { + eno = errno; + if (EADDRINUSE != errno) + { + /* we don't log 'EADDRINUSE' here since an IPv4 bind may + * fail if we already took the port on IPv6; if both IPv4 and + * IPv6 binds fail, then our caller will log using the + * errno preserved in 'eno' */ + LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, + "bind"); + if (0 != port) + LOG (GNUNET_ERROR_TYPE_ERROR, + _("`%s' failed for port %d (%s).\n"), + "bind", + port, + (AF_INET == server_addr->sa_family) ? "IPv4" : "IPv6"); + eno = 0; + } + else + { + if (0 != port) + LOG (GNUNET_ERROR_TYPE_WARNING, + _("`%s' failed for port %d (%s): address already in use\n"), + "bind", port, + (AF_INET == server_addr->sa_family) ? "IPv4" : "IPv6"); + else if (AF_UNIX == server_addr->sa_family) + { + LOG (GNUNET_ERROR_TYPE_WARNING, + _("`%s' failed for `%s': address already in use\n"), + "bind", + GNUNET_a2s (server_addr, socklen)); + } + } + GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock)); + errno = eno; + return NULL; + } + if (GNUNET_OK != GNUNET_NETWORK_socket_listen (sock, 5)) + { + LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, + "listen"); + GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock)); + errno = 0; + return NULL; + } + if (0 != port) + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server starts to listen on port %u.\n", + port); + return sock; +} + + +/** + * Create a new server. + * + * @param access_cb function for access control + * @param access_cb_cls closure for @a access_cb + * @param lsocks NULL-terminated array of listen sockets + * @param idle_timeout after how long should we timeout idle connections? + * @param require_found if #GNUNET_YES, connections sending messages of unknown type + * will be closed + * @return handle for the new server, NULL on error + * (typically, "port" already in use) + */ +struct GNUNET_SERVER_Handle * +GNUNET_SERVER_create_with_sockets (GNUNET_CONNECTION_AccessCheck access_cb, + void *access_cb_cls, + struct GNUNET_NETWORK_Handle **lsocks, + struct GNUNET_TIME_Relative idle_timeout, + int require_found) +{ + struct GNUNET_SERVER_Handle *server; + + server = GNUNET_new (struct GNUNET_SERVER_Handle); + server->idle_timeout = idle_timeout; + server->listen_sockets = lsocks; + server->access_cb = access_cb; + server->access_cb_cls = access_cb_cls; + server->require_found = require_found; + if (NULL != lsocks) + GNUNET_SERVER_resume (server); + return server; +} + + +/** + * Create a new server. + * + * @param access_cb function for access control + * @param access_cb_cls closure for @a access_cb + * @param server_addr address to listen on (including port), NULL terminated array + * @param socklen length of server_addr + * @param idle_timeout after how long should we timeout idle connections? + * @param require_found if YES, connections sending messages of unknown type + * will be closed + * @return handle for the new server, NULL on error + * (typically, "port" already in use) + */ +struct GNUNET_SERVER_Handle * +GNUNET_SERVER_create (GNUNET_CONNECTION_AccessCheck access_cb, + void *access_cb_cls, + struct sockaddr *const *server_addr, + const socklen_t * socklen, + struct GNUNET_TIME_Relative idle_timeout, + int require_found) +{ + struct GNUNET_NETWORK_Handle **lsocks; + unsigned int i; + unsigned int j; + unsigned int k; + int seen; + + i = 0; + while (NULL != server_addr[i]) + i++; + if (i > 0) + { + lsocks = GNUNET_malloc (sizeof (struct GNUNET_NETWORK_Handle *) * (i + 1)); + i = 0; + j = 0; + while (NULL != server_addr[i]) + { + seen = 0; + for (k=0;k<i;k++) + if ( (socklen[k] == socklen[i]) && + (0 == memcmp (server_addr[k], server_addr[i], socklen[i])) ) + { + seen = 1; + break; + } + if (0 != seen) + { + /* duplicate address, skip */ + i++; + continue; + } + lsocks[j] = open_listen_socket (server_addr[i], socklen[i]); + if (NULL != lsocks[j]) + j++; + i++; + } + if (0 == j) + { + if (0 != errno) + LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "bind"); + GNUNET_free (lsocks); + lsocks = NULL; + } + } + else + { + lsocks = NULL; + } + return GNUNET_SERVER_create_with_sockets (access_cb, + access_cb_cls, + lsocks, + idle_timeout, + require_found); +} + + +/** + * Set the 'monitor' flag on this client. Clients which have been + * marked as 'monitors' won't prevent the server from shutting down + * once '#GNUNET_SERVER_stop_listening()' has been invoked. The idea is + * that for "normal" clients we likely want to allow them to process + * their requests; however, monitor-clients are likely to 'never' + * disconnect during shutdown and thus will not be considered when + * determining if the server should continue to exist after + * #GNUNET_SERVER_destroy() has been called. + * + * @param client the client to set the 'monitor' flag on + */ +void +GNUNET_SERVER_client_mark_monitor (struct GNUNET_SERVER_Client *client) +{ + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Marking client as monitor!\n"); + client->is_monitor = GNUNET_YES; +} + + +/** + * Helper function for #test_monitor_clients() to trigger + * #GNUNET_SERVER_destroy() after the stack has unwound. + * + * @param cls the `struct GNUNET_SERVER_Handle *` to destroy + */ +static void +do_destroy (void *cls) +{ + struct GNUNET_SERVER_Handle *server = cls; + + GNUNET_SERVER_destroy (server); +} + + +/** + * Check if only 'monitor' clients are left. If so, destroy the + * server completely. + * + * @param server server to test for full shutdown + */ +static void +test_monitor_clients (struct GNUNET_SERVER_Handle *server) +{ + struct GNUNET_SERVER_Client *client; + + if (GNUNET_YES != server->in_soft_shutdown) + return; + for (client = server->clients_head; NULL != client; client = client->next) + if (GNUNET_NO == client->is_monitor) + return; /* not done yet */ + server->in_soft_shutdown = GNUNET_SYSERR; + (void) GNUNET_SCHEDULER_add_now (&do_destroy, server); +} + + +/** + * Suspend accepting connections from the listen socket temporarily. + * + * @param server server to stop accepting connections. + */ +void +GNUNET_SERVER_suspend (struct GNUNET_SERVER_Handle *server) +{ + if (NULL != server->listen_task) + { + GNUNET_SCHEDULER_cancel (server->listen_task); + server->listen_task = NULL; + } +} + + +/** + * Resume accepting connections from the listen socket. + * + * @param server server to stop accepting connections. + */ +void +GNUNET_SERVER_resume (struct GNUNET_SERVER_Handle *server) +{ + struct GNUNET_NETWORK_FDSet *r; + unsigned int i; + + if (NULL == server->listen_sockets) + return; + if (NULL == server->listen_sockets[0]) + return; /* nothing to do, no listen sockets! */ + if (NULL == server->listen_sockets[1]) + { + /* simplified method: no fd set needed; this is then much simpler + and much more efficient */ + server->listen_task = + GNUNET_SCHEDULER_add_read_net_with_priority (GNUNET_TIME_UNIT_FOREVER_REL, + GNUNET_SCHEDULER_PRIORITY_HIGH, + server->listen_sockets[0], + &process_listen_socket, server); + return; + } + r = GNUNET_NETWORK_fdset_create (); + i = 0; + while (NULL != server->listen_sockets[i]) + GNUNET_NETWORK_fdset_set (r, server->listen_sockets[i++]); + server->listen_task = + GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_HIGH, + GNUNET_TIME_UNIT_FOREVER_REL, r, NULL, + &process_listen_socket, server); + GNUNET_NETWORK_fdset_destroy (r); +} + + +/** + * Stop the listen socket and get ready to shutdown the server + * once only 'monitor' clients are left. + * + * @param server server to stop listening on + */ +void +GNUNET_SERVER_stop_listening (struct GNUNET_SERVER_Handle *server) +{ + unsigned int i; + + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server in soft shutdown\n"); + if (NULL != server->listen_task) + { + GNUNET_SCHEDULER_cancel (server->listen_task); + server->listen_task = NULL; + } + if (NULL != server->listen_sockets) + { + i = 0; + while (NULL != server->listen_sockets[i]) + GNUNET_break (GNUNET_OK == + GNUNET_NETWORK_socket_close (server->listen_sockets[i++])); + GNUNET_free (server->listen_sockets); + server->listen_sockets = NULL; + } + if (GNUNET_NO == server->in_soft_shutdown) + server->in_soft_shutdown = GNUNET_YES; + test_monitor_clients (server); +} + + +/** + * Free resources held by this server. + * + * @param server server to destroy + */ +void +GNUNET_SERVER_destroy (struct GNUNET_SERVER_Handle *server) +{ + struct HandlerList *hpos; + struct NotifyList *npos; + unsigned int i; + + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server shutting down.\n"); + if (NULL != server->listen_task) + { + GNUNET_SCHEDULER_cancel (server->listen_task); + server->listen_task = NULL; + } + if (NULL != server->listen_sockets) + { + i = 0; + while (NULL != server->listen_sockets[i]) + GNUNET_break (GNUNET_OK == + GNUNET_NETWORK_socket_close (server->listen_sockets[i++])); + GNUNET_free (server->listen_sockets); + server->listen_sockets = NULL; + } + while (NULL != server->clients_head) + GNUNET_SERVER_client_disconnect (server->clients_head); + while (NULL != (hpos = server->handlers)) + { + server->handlers = hpos->next; + GNUNET_free (hpos); + } + while (NULL != (npos = server->disconnect_notify_list_head)) + { + npos->callback (npos->callback_cls, + NULL); + GNUNET_CONTAINER_DLL_remove (server->disconnect_notify_list_head, + server->disconnect_notify_list_tail, + npos); + GNUNET_free (npos); + } + while (NULL != (npos = server->connect_notify_list_head)) + { + npos->callback (npos->callback_cls, + NULL); + GNUNET_CONTAINER_DLL_remove (server->connect_notify_list_head, + server->connect_notify_list_tail, + npos); + GNUNET_free (npos); + } + GNUNET_free (server); +} + + +/** + * Add additional handlers to an existing server. + * + * @param server the server to add handlers to + * @param handlers array of message handlers for + * incoming messages; the last entry must + * have "NULL" for the "callback"; multiple + * entries for the same type are allowed, + * they will be called in order of occurence. + * These handlers can be removed later; + * the handlers array must exist until removed + * (or server is destroyed). + */ +void +GNUNET_SERVER_add_handlers (struct GNUNET_SERVER_Handle *server, + const struct GNUNET_SERVER_MessageHandler *handlers) +{ + struct HandlerList *p; + + p = GNUNET_new (struct HandlerList); + p->handlers = handlers; + p->next = server->handlers; + server->handlers = p; +} + + +/** + * Change functions used by the server to tokenize the message stream. + * (very rarely used). + * + * @param server server to modify + * @param create new tokenizer initialization function + * @param destroy new tokenizer destruction function + * @param receive new tokenizer receive function + * @param cls closure for @a create, @a receive, @a destroy + */ +void +GNUNET_SERVER_set_callbacks (struct GNUNET_SERVER_Handle *server, + GNUNET_SERVER_MstCreateCallback create, + GNUNET_SERVER_MstDestroyCallback destroy, + GNUNET_SERVER_MstReceiveCallback receive, + void *cls) +{ + server->mst_create = create; + server->mst_destroy = destroy; + server->mst_receive = receive; + server->mst_cls = cls; +} + + +/** + * Task run to warn about missing calls to #GNUNET_SERVER_receive_done. + * + * @param cls our `struct GNUNET_SERVER_Client *` to process more requests from + */ +static void +warn_no_receive_done (void *cls) +{ + struct GNUNET_SERVER_Client *client = cls; + + GNUNET_break (0 != client->warn_type); /* type should never be 0 here, as we don't use 0 */ + client->warn_task = + GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES, + &warn_no_receive_done, client); + LOG (GNUNET_ERROR_TYPE_WARNING, + _("Processing code for message of type %u did not call `GNUNET_SERVER_receive_done' after %s\n"), + (unsigned int) client->warn_type, + GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (client->warn_start), + GNUNET_YES)); +} + + +/** + * Disable the warning the server issues if a message is not acknowledged + * in a timely fashion. Use this call if a client is intentionally delayed + * for a while. Only applies to the current message. + * + * @param client client for which to disable the warning + */ +void +GNUNET_SERVER_disable_receive_done_warning (struct GNUNET_SERVER_Client *client) +{ + if (NULL != client->warn_task) + { + GNUNET_SCHEDULER_cancel (client->warn_task); + client->warn_task = NULL; + } +} + + +/** + * Inject a message into the server, pretend it came + * from the specified client. Delivery of the message + * will happen instantly (if a handler is installed; + * otherwise the call does nothing). + * + * @param server the server receiving the message + * @param sender the "pretended" sender of the message + * can be NULL! + * @param message message to transmit + * @return #GNUNET_OK if the message was OK and the + * connection can stay open + * #GNUNET_SYSERR if the connection to the + * client should be shut down + */ +int +GNUNET_SERVER_inject (struct GNUNET_SERVER_Handle *server, + struct GNUNET_SERVER_Client *sender, + const struct GNUNET_MessageHeader *message) +{ + struct HandlerList *pos; + const struct GNUNET_SERVER_MessageHandler *mh; + unsigned int i; + uint16_t type; + uint16_t size; + int found; + + type = ntohs (message->type); + size = ntohs (message->size); + LOG (GNUNET_ERROR_TYPE_INFO, + "Received message of type %u and size %u from client\n", + type, size); + found = GNUNET_NO; + for (pos = server->handlers; NULL != pos; pos = pos->next) + { + i = 0; + while (pos->handlers[i].callback != NULL) + { + mh = &pos->handlers[i]; + if ((mh->type == type) || (mh->type == GNUNET_MESSAGE_TYPE_ALL)) + { + if ((0 != mh->expected_size) && (mh->expected_size != size)) + { +#if GNUNET8_NETWORK_IS_DEAD + LOG (GNUNET_ERROR_TYPE_WARNING, + "Expected %u bytes for message of type %u, got %u\n", + mh->expected_size, mh->type, size); + GNUNET_break_op (0); +#else + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Expected %u bytes for message of type %u, got %u\n", + mh->expected_size, mh->type, size); +#endif + return GNUNET_SYSERR; + } + if (NULL != sender) + { + if ( (0 == sender->suspended) && + (NULL == sender->warn_task) ) + { + GNUNET_break (0 != type); /* type should never be 0 here, as we don't use 0 */ + sender->warn_start = GNUNET_TIME_absolute_get (); + sender->warn_task = + GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES, + &warn_no_receive_done, + sender); + sender->warn_type = type; + } + sender->suspended++; + } + mh->callback (mh->callback_cls, sender, message); + found = GNUNET_YES; + } + i++; + } + } + if (GNUNET_NO == found) + { + LOG (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK, + "Received message of unknown type %d\n", type); + if (GNUNET_YES == server->require_found) + return GNUNET_SYSERR; + } + return GNUNET_OK; +} + + +/** + * We are receiving an incoming message. Process it. + * + * @param cls our closure (handle for the client) + * @param buf buffer with data received from network + * @param available number of bytes available in buf + * @param addr address of the sender + * @param addrlen length of @a addr + * @param errCode code indicating errors receiving, 0 for success + */ +static void +process_incoming (void *cls, + const void *buf, + size_t available, + const struct sockaddr *addr, + socklen_t addrlen, + int errCode); + + +/** + * Process messages from the client's message tokenizer until either + * the tokenizer is empty (and then schedule receiving more), or + * until some handler is not immediately done (then wait for restart_processing) + * or shutdown. + * + * @param client the client to process, RC must have already been increased + * using #GNUNET_SERVER_client_keep and will be decreased by one in this + * function + * @param ret #GNUNET_NO to start processing from the buffer, + * #GNUNET_OK if the mst buffer is drained and we should instantly go back to receiving + * #GNUNET_SYSERR if we should instantly abort due to error in a previous step + */ +static void +process_mst (struct GNUNET_SERVER_Client *client, + int ret) +{ + while ((GNUNET_SYSERR != ret) && (NULL != client->server) && + (GNUNET_YES != client->shutdown_now) && (0 == client->suspended)) + { + if (GNUNET_OK == ret) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server re-enters receive loop, timeout: %s.\n", + GNUNET_STRINGS_relative_time_to_string (client->idle_timeout, GNUNET_YES)); + client->receive_pending = GNUNET_YES; + GNUNET_CONNECTION_receive (client->connection, + GNUNET_SERVER_MAX_MESSAGE_SIZE - 1, + client->idle_timeout, + &process_incoming, + client); + break; + } + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server processes additional messages instantly.\n"); + if (NULL != client->server->mst_receive) + ret = + client->server->mst_receive (client->server->mst_cls, client->mst, + client, NULL, 0, GNUNET_NO, GNUNET_YES); + else + ret = + GNUNET_SERVER_mst_receive (client->mst, client, NULL, 0, GNUNET_NO, + GNUNET_YES); + } + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server leaves instant processing loop: ret = %d, server = %p, shutdown = %d, suspended = %u\n", + ret, client->server, + client->shutdown_now, + client->suspended); + if (GNUNET_NO == ret) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server has more data pending but is suspended.\n"); + client->receive_pending = GNUNET_SYSERR; /* data pending */ + } + if ( (GNUNET_SYSERR == ret) || + (GNUNET_YES == client->shutdown_now) ) + GNUNET_SERVER_client_disconnect (client); +} + + +/** + * We are receiving an incoming message. Process it. + * + * @param cls our closure (handle for the client) + * @param buf buffer with data received from network + * @param available number of bytes available in buf + * @param addr address of the sender + * @param addrlen length of @a addr + * @param errCode code indicating errors receiving, 0 for success + */ +static void +process_incoming (void *cls, + const void *buf, + size_t available, + const struct sockaddr *addr, + socklen_t addrlen, + int errCode) +{ + struct GNUNET_SERVER_Client *client = cls; + struct GNUNET_SERVER_Handle *server = client->server; + struct GNUNET_TIME_Absolute end; + struct GNUNET_TIME_Absolute now; + int ret; + + GNUNET_assert (GNUNET_YES == client->receive_pending); + client->receive_pending = GNUNET_NO; + now = GNUNET_TIME_absolute_get (); + end = GNUNET_TIME_absolute_add (client->last_activity, + client->idle_timeout); + + if ( (NULL == buf) && + (0 == available) && + (NULL == addr) && + (0 == errCode) && + (GNUNET_YES != client->shutdown_now) && + (NULL != server) && + (GNUNET_YES == GNUNET_CONNECTION_check (client->connection)) && + (end.abs_value_us > now.abs_value_us) ) + { + /* wait longer, timeout changed (i.e. due to us sending) */ + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Receive time out, but no disconnect due to sending (%p)\n", + client); + client->receive_pending = GNUNET_YES; + GNUNET_CONNECTION_receive (client->connection, + GNUNET_SERVER_MAX_MESSAGE_SIZE - 1, + GNUNET_TIME_absolute_get_remaining (end), + &process_incoming, + client); + return; + } + if ( (NULL == buf) || + (0 == available) || + (0 != errCode) || + (NULL == server) || + (GNUNET_YES == client->shutdown_now) || + (GNUNET_YES != GNUNET_CONNECTION_check (client->connection)) ) + { + /* other side closed connection, error connecting, etc. */ + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Failed to connect or other side closed connection (%p)\n", + client); + GNUNET_SERVER_client_disconnect (client); + return; + } + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server receives %u bytes from `%s'.\n", + (unsigned int) available, + GNUNET_a2s (addr, addrlen)); + GNUNET_SERVER_client_keep (client); + client->last_activity = now; + + if (NULL != server->mst_receive) + { + ret = client->server->mst_receive (client->server->mst_cls, + client->mst, + client, + buf, + available, + GNUNET_NO, + GNUNET_YES); + } + else if (NULL != client->mst) + { + ret = + GNUNET_SERVER_mst_receive (client->mst, + client, + buf, + available, + GNUNET_NO, + GNUNET_YES); + } + else + { + GNUNET_break (0); + return; + } + process_mst (client, + ret); + GNUNET_SERVER_client_drop (client); +} + + +/** + * Task run to start again receiving from the network + * and process requests. + * + * @param cls our `struct GNUNET_SERVER_Client *` to process more requests from + */ +static void +restart_processing (void *cls) +{ + struct GNUNET_SERVER_Client *client = cls; + + GNUNET_assert (GNUNET_YES != client->shutdown_now); + client->restart_task = NULL; + if (GNUNET_NO == client->receive_pending) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, "Server begins to read again from client.\n"); + client->receive_pending = GNUNET_YES; + GNUNET_CONNECTION_receive (client->connection, + GNUNET_SERVER_MAX_MESSAGE_SIZE - 1, + client->idle_timeout, + &process_incoming, + client); + return; + } + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Server continues processing messages still in the buffer.\n"); + GNUNET_SERVER_client_keep (client); + client->receive_pending = GNUNET_NO; + process_mst (client, + GNUNET_NO); + GNUNET_SERVER_client_drop (client); +} + + +/** + * This function is called whenever our inbound message tokenizer has + * received a complete message. + * + * @param cls closure (struct GNUNET_SERVER_Handle) + * @param client identification of the client (`struct GNUNET_SERVER_Client *`) + * @param message the actual message + * + * @return #GNUNET_OK on success, #GNUNET_SYSERR to stop further processing + */ +static int +client_message_tokenizer_callback (void *cls, + void *client, + const struct GNUNET_MessageHeader *message) +{ + struct GNUNET_SERVER_Handle *server = cls; + struct GNUNET_SERVER_Client *sender = client; + int ret; + + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Tokenizer gives server message of type %u and size %u from client\n", + ntohs (message->type), ntohs (message->size)); + sender->in_process_client_buffer = GNUNET_YES; + ret = GNUNET_SERVER_inject (server, sender, message); + sender->in_process_client_buffer = GNUNET_NO; + if ( (GNUNET_OK != ret) || (GNUNET_YES == sender->shutdown_now) ) + { + GNUNET_SERVER_client_disconnect (sender); + return GNUNET_SYSERR; + } + return GNUNET_OK; +} + + +/** + * Add a TCP socket-based connection to the set of handles managed by + * this server. Use this function for outgoing (P2P) connections that + * we initiated (and where this server should process incoming + * messages). + * + * @param server the server to use + * @param connection the connection to manage (client must + * stop using this connection from now on) + * @return the client handle + */ +struct GNUNET_SERVER_Client * +GNUNET_SERVER_connect_socket (struct GNUNET_SERVER_Handle *server, + struct GNUNET_CONNECTION_Handle *connection) +{ + struct GNUNET_SERVER_Client *client; + struct NotifyList *n; + + client = GNUNET_new (struct GNUNET_SERVER_Client); + client->connection = connection; + client->server = server; + client->last_activity = GNUNET_TIME_absolute_get (); + client->idle_timeout = server->idle_timeout; + GNUNET_CONTAINER_DLL_insert (server->clients_head, + server->clients_tail, + client); + if (NULL != server->mst_create) + client->mst = + server->mst_create (server->mst_cls, client); + else + client->mst = + GNUNET_SERVER_mst_create (&client_message_tokenizer_callback, + server); + GNUNET_assert (NULL != client->mst); + for (n = server->connect_notify_list_head; NULL != n; n = n->next) + n->callback (n->callback_cls, client); + client->receive_pending = GNUNET_YES; + GNUNET_CONNECTION_receive (client->connection, + GNUNET_SERVER_MAX_MESSAGE_SIZE - 1, + client->idle_timeout, + &process_incoming, + client); + return client; +} + + +/** + * Change the timeout for a particular client. Decreasing the timeout + * may not go into effect immediately (only after the previous timeout + * times out or activity happens on the socket). + * + * @param client the client to update + * @param timeout new timeout for activities on the socket + */ +void +GNUNET_SERVER_client_set_timeout (struct GNUNET_SERVER_Client *client, + struct GNUNET_TIME_Relative timeout) +{ + client->idle_timeout = timeout; +} + + +/** + * Notify the server that the given client handle should + * be kept (keeps the connection up if possible, increments + * the internal reference counter). + * + * @param client the client to keep + */ +void +GNUNET_SERVER_client_keep (struct GNUNET_SERVER_Client *client) +{ + client->reference_count++; +} + + +/** + * Notify the server that the given client handle is no + * longer required. Decrements the reference counter. If + * that counter reaches zero an inactive connection maybe + * closed. + * + * @param client the client to drop + */ +void +GNUNET_SERVER_client_drop (struct GNUNET_SERVER_Client *client) +{ + GNUNET_assert (client->reference_count > 0); + client->reference_count--; + if ((GNUNET_YES == client->shutdown_now) && (0 == client->reference_count)) + GNUNET_SERVER_client_disconnect (client); +} + + +/** + * Obtain the network address of the other party. + * + * @param client the client to get the address for + * @param addr where to store the address + * @param addrlen where to store the length of the @a addr + * @return #GNUNET_OK on success + */ +int +GNUNET_SERVER_client_get_address (struct GNUNET_SERVER_Client *client, + void **addr, size_t * addrlen) +{ + return GNUNET_CONNECTION_get_address (client->connection, addr, addrlen); +} + + +/** + * Ask the server to notify us whenever a client disconnects. + * This function is called whenever the actual network connection + * is closed; the reference count may be zero or larger than zero + * at this point. + * + * @param server the server manageing the clients + * @param callback function to call on disconnect + * @param callback_cls closure for @a callback + */ +void +GNUNET_SERVER_disconnect_notify (struct GNUNET_SERVER_Handle *server, + GNUNET_SERVER_DisconnectCallback callback, + void *callback_cls) +{ + struct NotifyList *n; + + n = GNUNET_new (struct NotifyList); + n->callback = callback; + n->callback_cls = callback_cls; + GNUNET_CONTAINER_DLL_insert (server->disconnect_notify_list_head, + server->disconnect_notify_list_tail, + n); +} + + +/** + * Ask the server to notify us whenever a client connects. + * This function is called whenever the actual network connection + * is opened. If the server is destroyed before this + * notification is explicitly cancelled, the 'callback' will + * once be called with a 'client' argument of NULL to indicate + * that the server itself is now gone (and that the callback + * won't be called anymore and also can no longer be cancelled). + * + * @param server the server manageing the clients + * @param callback function to call on sconnect + * @param callback_cls closure for @a callback + */ +void +GNUNET_SERVER_connect_notify (struct GNUNET_SERVER_Handle *server, + GNUNET_SERVER_ConnectCallback callback, + void *callback_cls) +{ + struct NotifyList *n; + struct GNUNET_SERVER_Client *client; + + n = GNUNET_new (struct NotifyList); + n->callback = callback; + n->callback_cls = callback_cls; + GNUNET_CONTAINER_DLL_insert (server->connect_notify_list_head, + server->connect_notify_list_tail, + n); + for (client = server->clients_head; NULL != client; client = client->next) + callback (callback_cls, client); +} + + +/** + * Ask the server to stop notifying us whenever a client connects. + * + * @param server the server manageing the clients + * @param callback function to call on connect + * @param callback_cls closure for @a callback + */ +void +GNUNET_SERVER_disconnect_notify_cancel (struct GNUNET_SERVER_Handle *server, + GNUNET_SERVER_DisconnectCallback callback, + void *callback_cls) +{ + struct NotifyList *pos; + + for (pos = server->disconnect_notify_list_head; NULL != pos; pos = pos->next) + if ((pos->callback == callback) && (pos->callback_cls == callback_cls)) + break; + if (NULL == pos) + { + GNUNET_break (0); + return; + } + GNUNET_CONTAINER_DLL_remove (server->disconnect_notify_list_head, + server->disconnect_notify_list_tail, + pos); + GNUNET_free (pos); +} + + +/** + * Ask the server to stop notifying us whenever a client disconnects. + * + * @param server the server manageing the clients + * @param callback function to call on disconnect + * @param callback_cls closure for @a callback + */ +void +GNUNET_SERVER_connect_notify_cancel (struct GNUNET_SERVER_Handle *server, + GNUNET_SERVER_ConnectCallback callback, + void *callback_cls) +{ + struct NotifyList *pos; + + for (pos = server->connect_notify_list_head; NULL != pos; pos = pos->next) + if ((pos->callback == callback) && (pos->callback_cls == callback_cls)) + break; + if (NULL == pos) + { + GNUNET_break (0); + return; + } + GNUNET_CONTAINER_DLL_remove (server->connect_notify_list_head, + server->connect_notify_list_tail, + pos); + GNUNET_free (pos); +} + + +/** + * Destroy the connection that is passed in via @a cls. Used + * as calling #GNUNET_CONNECTION_destroy from within a function + * that was itself called from within process_notify() of + * 'connection.c' is not allowed (see #2329). + * + * @param cls connection to destroy + */ +static void +destroy_connection (void *cls) +{ + struct GNUNET_CONNECTION_Handle *connection = cls; + + GNUNET_CONNECTION_destroy (connection); +} + + +/** + * Ask the server to disconnect from the given client. + * This is the same as returning #GNUNET_SYSERR from a message + * handler, except that it allows dropping of a client even + * when not handling a message from that client. + * + * @param client the client to disconnect from + */ +void +GNUNET_SERVER_client_disconnect (struct GNUNET_SERVER_Client *client) +{ + struct GNUNET_SERVER_Handle *server = client->server; + struct NotifyList *n; + + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Client is being disconnected from the server.\n"); + if (NULL != client->restart_task) + { + GNUNET_SCHEDULER_cancel (client->restart_task); + client->restart_task = NULL; + } + if (NULL != client->warn_task) + { + GNUNET_SCHEDULER_cancel (client->warn_task); + client->warn_task = NULL; + } + if (GNUNET_YES == client->receive_pending) + { + GNUNET_CONNECTION_receive_cancel (client->connection); + client->receive_pending = GNUNET_NO; + } + client->shutdown_now = GNUNET_YES; + client->reference_count++; /* make sure nobody else clean up client... */ + if ( (NULL != client->mst) && + (NULL != server) ) + { + GNUNET_CONTAINER_DLL_remove (server->clients_head, + server->clients_tail, + client); + if (NULL != server->mst_destroy) + server->mst_destroy (server->mst_cls, + client->mst); + else + GNUNET_SERVER_mst_destroy (client->mst); + client->mst = NULL; + for (n = server->disconnect_notify_list_head; NULL != n; n = n->next) + n->callback (n->callback_cls, + client); + } + client->reference_count--; + if (client->reference_count > 0) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "RC of %p still positive, not destroying everything.\n", + client); + client->server = NULL; + return; + } + if (GNUNET_YES == client->in_process_client_buffer) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Still processing inputs of %p, not destroying everything.\n", + client); + return; + } + LOG (GNUNET_ERROR_TYPE_DEBUG, + "RC of %p now zero, destroying everything.\n", + client); + if (GNUNET_YES == client->persist) + GNUNET_CONNECTION_persist_ (client->connection); + if (NULL != client->th.cth) + GNUNET_SERVER_notify_transmit_ready_cancel (&client->th); + (void) GNUNET_SCHEDULER_add_now (&destroy_connection, + client->connection); + /* need to cancel again, as it might have been re-added + in the meantime (i.e. during callbacks) */ + if (NULL != client->warn_task) + { + GNUNET_SCHEDULER_cancel (client->warn_task); + client->warn_task = NULL; + } + if (GNUNET_YES == client->receive_pending) + { + GNUNET_CONNECTION_receive_cancel (client->connection); + client->receive_pending = GNUNET_NO; + } + GNUNET_free (client); + /* we might be in soft-shutdown, test if we're done */ + if (NULL != server) + test_monitor_clients (server); +} + + +/** + * Disable the "CORK" feature for communication with the given client, + * forcing the OS to immediately flush the buffer on transmission + * instead of potentially buffering multiple messages. + * + * @param client handle to the client + * @return #GNUNET_OK on success + */ +int +GNUNET_SERVER_client_disable_corking (struct GNUNET_SERVER_Client *client) +{ + return GNUNET_CONNECTION_disable_corking (client->connection); +} + + +/** + * Wrapper for transmission notification that calls the original + * callback and update the last activity time for our connection. + * + * @param cls the `struct GNUNET_SERVER_Client *` + * @param size number of bytes we can transmit + * @param buf where to copy the message + * @return number of bytes actually transmitted + */ +static size_t +transmit_ready_callback_wrapper (void *cls, size_t size, void *buf) +{ + struct GNUNET_SERVER_Client *client = cls; + GNUNET_CONNECTION_TransmitReadyNotify callback; + + client->th.cth = NULL; + callback = client->th.callback; + client->th.callback = NULL; + client->last_activity = GNUNET_TIME_absolute_get (); + return callback (client->th.callback_cls, size, buf); +} + + +/** + * Notify us when the server has enough space to transmit + * a message of the given size to the given client. + * + * @param client client to transmit message to + * @param size requested amount of buffer space + * @param timeout after how long should we give up (and call + * notify with buf NULL and size 0)? + * @param callback function to call when space is available + * @param callback_cls closure for @a callback + * @return non-NULL if the notify callback was queued; can be used + * to cancel the request using + * #GNUNET_SERVER_notify_transmit_ready_cancel(). + * NULL if we are already going to notify someone else (busy) + */ +struct GNUNET_SERVER_TransmitHandle * +GNUNET_SERVER_notify_transmit_ready (struct GNUNET_SERVER_Client *client, + size_t size, + struct GNUNET_TIME_Relative timeout, + GNUNET_CONNECTION_TransmitReadyNotify callback, + void *callback_cls) +{ + if (NULL != client->th.callback) + return NULL; + client->th.callback_cls = callback_cls; + client->th.callback = callback; + client->th.cth = GNUNET_CONNECTION_notify_transmit_ready (client->connection, size, + timeout, + &transmit_ready_callback_wrapper, + client); + return &client->th; +} + + +/** + * Abort transmission request. + * + * @param th request to abort + */ +void +GNUNET_SERVER_notify_transmit_ready_cancel (struct GNUNET_SERVER_TransmitHandle *th) +{ + GNUNET_CONNECTION_notify_transmit_ready_cancel (th->cth); + th->cth = NULL; + th->callback = NULL; +} + + +/** + * Set the persistent flag on this client, used to setup client connection + * to only be killed when the service it's connected to is actually dead. + * + * @param client the client to set the persistent flag on + */ +void +GNUNET_SERVER_client_persist_ (struct GNUNET_SERVER_Client *client) +{ + client->persist = GNUNET_YES; +} + + +/** + * Resume receiving from this client, we are done processing the + * current request. This function must be called from within each + * GNUNET_SERVER_MessageCallback (or its respective continuations). + * + * @param client client we were processing a message of + * @param success #GNUNET_OK to keep the connection open and + * continue to receive + * #GNUNET_NO to close the connection (normal behavior) + * #GNUNET_SYSERR to close the connection (signal + * serious error) + */ +void +GNUNET_SERVER_receive_done (struct GNUNET_SERVER_Client *client, + int success) +{ + if (NULL == client) + return; + GNUNET_assert (client->suspended > 0); + client->suspended--; + if (GNUNET_OK != success) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "GNUNET_SERVER_receive_done called with failure indication\n"); + if ( (client->reference_count > 0) || (client->suspended > 0) ) + client->shutdown_now = GNUNET_YES; + else + GNUNET_SERVER_client_disconnect (client); + return; + } + if (client->suspended > 0) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "GNUNET_SERVER_receive_done called, but more clients pending\n"); + return; + } + if (NULL != client->warn_task) + { + GNUNET_SCHEDULER_cancel (client->warn_task); + client->warn_task = NULL; + } + if (GNUNET_YES == client->in_process_client_buffer) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "GNUNET_SERVER_receive_done called while still in processing loop\n"); + return; + } + if ((NULL == client->server) || (GNUNET_YES == client->shutdown_now)) + { + GNUNET_SERVER_client_disconnect (client); + return; + } + LOG (GNUNET_ERROR_TYPE_DEBUG, + "GNUNET_SERVER_receive_done causes restart in reading from the socket\n"); + GNUNET_assert (NULL == client->restart_task); + client->restart_task = GNUNET_SCHEDULER_add_now (&restart_processing, + client); +} + + +/* end of server.c */ |