/* This file is part of GNUnet Copyright (C) 2010-2017 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/plugin_transport_xu.c * @brief Implementation of the XU transport protocol * @author Christian Grothoff * @author Nathan Evans * @author Matthias Wachs */ #include "platform.h" #include "plugin_transport_xu.h" #include "gnunet_hello_lib.h" #include "gnunet_util_lib.h" #include "gnunet_fragmentation_lib.h" #include "gnunet_nat_service.h" #include "gnunet_protocols.h" #include "gnunet_resolver_service.h" #include "gnunet_signatures.h" #include "gnunet_constants.h" #include "gnunet_statistics_service.h" #include "gnunet_transport_service.h" #include "gnunet_transport_plugin.h" #include "transport.h" #define LOG(kind,...) GNUNET_log_from (kind, "transport-xu", __VA_ARGS__) /** * After how much inactivity should a XU session time out? */ #define XU_SESSION_TIME_OUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60) /** * XU Message-Packet header (after defragmentation). */ struct XUMessage { /** * Message header. */ struct GNUNET_MessageHeader header; /** * Always zero for now. */ uint32_t reserved; /** * What is the identity of the sender */ struct GNUNET_PeerIdentity sender; }; /** * Closure for #append_port(). */ struct PrettyPrinterContext { /** * DLL */ struct PrettyPrinterContext *next; /** * DLL */ struct PrettyPrinterContext *prev; /** * Our plugin. */ struct Plugin *plugin; /** * Resolver handle */ struct GNUNET_RESOLVER_RequestHandle *resolver_handle; /** * Function to call with the result. */ GNUNET_TRANSPORT_AddressStringCallback asc; /** * Clsoure for @e asc. */ void *asc_cls; /** * Timeout task */ struct GNUNET_SCHEDULER_Task *timeout_task; /** * Is this an IPv6 address? */ int ipv6; /** * Options */ uint32_t options; /** * Port to add after the IP address. */ uint16_t port; }; /** * Session with another peer. */ struct GNUNET_ATS_Session { /** * Which peer is this session for? */ struct GNUNET_PeerIdentity target; /** * Tokenizer for inbound messages. */ struct GNUNET_MessageStreamTokenizer *mst; /** * Plugin this session belongs to. */ struct Plugin *plugin; /** * Session timeout task */ struct GNUNET_SCHEDULER_Task *timeout_task; /** * When does this session time out? */ struct GNUNET_TIME_Absolute timeout; /** * What time did we last transmit? */ struct GNUNET_TIME_Absolute last_transmit_time; /** * expected delay for ACKs */ struct GNUNET_TIME_Relative last_expected_ack_delay; /** * desired delay between XU messages */ struct GNUNET_TIME_Relative last_expected_msg_delay; /** */ struct GNUNET_TIME_Relative flow_delay_for_other_peer; struct GNUNET_TIME_Relative flow_delay_from_other_peer; /** * Our own address. */ struct GNUNET_HELLO_Address *address; /** * Number of bytes waiting for transmission to this peer. */ unsigned long long bytes_in_queue; /** * Number of messages waiting for transmission to this peer. */ unsigned int msgs_in_queue; /** * Reference counter to indicate that this session is * currently being used and must not be destroyed; * setting @e in_destroy will destroy it as soon as * possible. */ unsigned int rc; /** * Network type of the address. */ enum GNUNET_NetworkType scope; /** * Is this session about to be destroyed (sometimes we cannot * destroy a session immediately as below us on the stack * there might be code that still uses it; in this case, * @e rc is non-zero). */ int in_destroy; }; /** * If a session monitor is attached, notify it about the new * session state. * * @param plugin our plugin * @param session session that changed state * @param state new state of the session */ static void notify_session_monitor (struct Plugin *plugin, struct GNUNET_ATS_Session *session, enum GNUNET_TRANSPORT_SessionState state) { struct GNUNET_TRANSPORT_SessionInfo info; if (NULL == plugin->sic) return; if (GNUNET_YES == session->in_destroy) return; /* already destroyed, just RC>0 left-over actions */ memset (&info, 0, sizeof (info)); info.state = state; info.is_inbound = GNUNET_SYSERR; /* hard to say */ info.num_msg_pending = session->msgs_in_queue; info.num_bytes_pending = session->bytes_in_queue; /* info.receive_delay remains zero as this is not supported by XU (cannot selectively not receive from 'some' peer while continuing to receive from others) */ info.session_timeout = session->timeout; info.address = session->address; plugin->sic (plugin->sic_cls, session, &info); } /** * Return information about the given session to the monitor callback. * * @param cls the `struct Plugin` with the monitor callback (`sic`) * @param peer peer we send information about * @param value our `struct GNUNET_ATS_Session` to send information about * @return #GNUNET_OK (continue to iterate) */ static int send_session_info_iter (void *cls, const struct GNUNET_PeerIdentity *peer, void *value) { struct Plugin *plugin = cls; struct GNUNET_ATS_Session *session = value; (void) peer; notify_session_monitor (plugin, session, GNUNET_TRANSPORT_SS_INIT); notify_session_monitor (plugin, session, GNUNET_TRANSPORT_SS_UP); return GNUNET_OK; } /** * Begin monitoring sessions of a plugin. There can only * be one active monitor per plugin (i.e. if there are * multiple monitors, the transport service needs to * multiplex the generated events over all of them). * * @param cls closure of the plugin * @param sic callback to invoke, NULL to disable monitor; * plugin will being by iterating over all active * sessions immediately and then enter monitor mode * @param sic_cls closure for @a sic */ static void xu_plugin_setup_monitor (void *cls, GNUNET_TRANSPORT_SessionInfoCallback sic, void *sic_cls) { struct Plugin *plugin = cls; plugin->sic = sic; plugin->sic_cls = sic_cls; if (NULL != sic) { GNUNET_CONTAINER_multipeermap_iterate (plugin->sessions, &send_session_info_iter, plugin); /* signal end of first iteration */ sic (sic_cls, NULL, NULL); } } /* ****************** Little Helpers ****************** */ /** * Function to free last resources associated with a session. * * @param s session to free */ static void free_session (struct GNUNET_ATS_Session *s) { if (NULL != s->address) { GNUNET_HELLO_address_free (s->address); s->address = NULL; } if (NULL != s->mst) { GNUNET_MST_destroy (s->mst); s->mst = NULL; } GNUNET_free (s); } /** * Function that is called to get the keepalive factor. * #GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT is divided by this number to * calculate the interval between keepalive packets. * * @param cls closure with the `struct Plugin` * @return keepalive factor */ static unsigned int xu_query_keepalive_factor (void *cls) { (void) cls; return 15; } /** * Function obtain the network type for a session * * @param cls closure (`struct Plugin *`) * @param session the session * @return the network type */ static enum GNUNET_NetworkType xu_plugin_get_network (void *cls, struct GNUNET_ATS_Session *session) { (void) cls; return session->scope; } /** * Function obtain the network type for an address. * * @param cls closure (`struct Plugin *`) * @param address the address * @return the network type */ static enum GNUNET_NetworkType xu_plugin_get_network_for_address (void *cls, const struct GNUNET_HELLO_Address *address) { struct Plugin *plugin = cls; size_t addrlen; struct sockaddr_in a4; struct sockaddr_in6 a6; const struct IPv4XuAddress *u4; const struct IPv6XuAddress *u6; const void *sb; size_t sbs; addrlen = address->address_length; if (addrlen == sizeof(struct IPv6XuAddress)) { GNUNET_assert (NULL != address->address); /* make static analysis happy */ u6 = address->address; memset (&a6, 0, sizeof(a6)); #if HAVE_SOCKADDR_IN_SIN_LEN a6.sin6_len = sizeof (a6); #endif a6.sin6_family = AF_INET6; a6.sin6_port = u6->u6_port; GNUNET_memcpy (&a6.sin6_addr, &u6->ipv6_addr, sizeof(struct in6_addr)); sb = &a6; sbs = sizeof(a6); } else if (addrlen == sizeof(struct IPv4XuAddress)) { GNUNET_assert (NULL != address->address); /* make static analysis happy */ u4 = address->address; memset (&a4, 0, sizeof(a4)); #if HAVE_SOCKADDR_IN_SIN_LEN a4.sin_len = sizeof (a4); #endif a4.sin_family = AF_INET; a4.sin_port = u4->u4_port; a4.sin_addr.s_addr = u4->ipv4_addr; sb = &a4; sbs = sizeof(a4); } else { GNUNET_break (0); return GNUNET_NT_UNSPECIFIED; } return plugin->env->get_address_type (plugin->env->cls, sb, sbs); } /* ******************* Event loop ******************** */ /** * We have been notified that our readset has something to read. We don't * know which socket needs to be read, so we have to check each one * Then reschedule this function to be called again once more is available. * * @param cls the plugin handle */ static void xu_plugin_select_v4 (void *cls); /** * We have been notified that our readset has something to read. We don't * know which socket needs to be read, so we have to check each one * Then reschedule this function to be called again once more is available. * * @param cls the plugin handle */ static void xu_plugin_select_v6 (void *cls); /** * (re)schedule IPv4-select tasks for this plugin. * * @param plugin plugin to reschedule */ static void schedule_select_v4 (struct Plugin *plugin) { if ( (GNUNET_YES != plugin->enable_ipv4) || (NULL == plugin->sockv4) ) return; if (NULL != plugin->select_task_v4) GNUNET_SCHEDULER_cancel (plugin->select_task_v4); plugin->select_task_v4 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, plugin->sockv4, &xu_plugin_select_v4, plugin); } /** * (re)schedule IPv6-select tasks for this plugin. * * @param plugin plugin to reschedule */ static void schedule_select_v6 (struct Plugin *plugin) { if ( (GNUNET_YES != plugin->enable_ipv6) || (NULL == plugin->sockv6) ) return; if (NULL != plugin->select_task_v6) GNUNET_SCHEDULER_cancel (plugin->select_task_v6); plugin->select_task_v6 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, plugin->sockv6, &xu_plugin_select_v6, plugin); } /* ******************* Address to string and back ***************** */ /** * Function called for a quick conversion of the binary address to * a numeric address. Note that the caller must not free the * address and that the next call to this function is allowed * to override the address again. * * @param cls closure * @param addr binary address (a `union XuAddress`) * @param addrlen length of the @a addr * @return string representing the same address */ const char * xu_address_to_string (void *cls, const void *addr, size_t addrlen) { static char rbuf[INET6_ADDRSTRLEN + 10]; char buf[INET6_ADDRSTRLEN]; const void *sb; struct in_addr a4; struct in6_addr a6; const struct IPv4XuAddress *t4; const struct IPv6XuAddress *t6; int af; uint16_t port; uint32_t options; (void) cls; if (NULL == addr) { GNUNET_break_op (0); return NULL; } if (addrlen == sizeof(struct IPv6XuAddress)) { t6 = addr; af = AF_INET6; options = ntohl (t6->options); port = ntohs (t6->u6_port); a6 = t6->ipv6_addr; sb = &a6; } else if (addrlen == sizeof(struct IPv4XuAddress)) { t4 = addr; af = AF_INET; options = ntohl (t4->options); port = ntohs (t4->u4_port); a4.s_addr = t4->ipv4_addr; sb = &a4; } else { GNUNET_break_op (0); return NULL; } inet_ntop (af, sb, buf, INET6_ADDRSTRLEN); GNUNET_snprintf (rbuf, sizeof(rbuf), (af == AF_INET6) ? "%s.%u.[%s]:%u" : "%s.%u.%s:%u", PLUGIN_NAME, options, buf, port); return rbuf; } /** * Function called to convert a string address to a binary address. * * @param cls closure (`struct Plugin *`) * @param addr string address * @param addrlen length of the address * @param buf location to store the buffer * @param added location to store the number of bytes in the buffer. * If the function returns #GNUNET_SYSERR, its contents are undefined. * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure */ static int xu_string_to_address (void *cls, const char *addr, uint16_t addrlen, void **buf, size_t *added) { struct sockaddr_storage socket_address; char *address; char *plugin; char *optionstr; uint32_t options; (void) cls; /* Format tcp.options.address:port */ address = NULL; plugin = NULL; optionstr = NULL; if ((NULL == addr) || (0 == addrlen)) { GNUNET_break (0); return GNUNET_SYSERR; } if ('\0' != addr[addrlen - 1]) { GNUNET_break (0); return GNUNET_SYSERR; } if (strlen (addr) + 1 != (size_t) addrlen) { GNUNET_break (0); return GNUNET_SYSERR; } plugin = GNUNET_strdup (addr); optionstr = strchr (plugin, '.'); if (NULL == optionstr) { GNUNET_break (0); GNUNET_free (plugin); return GNUNET_SYSERR; } optionstr[0] = '\0'; optionstr++; options = atol (optionstr); address = strchr (optionstr, '.'); if (NULL == address) { GNUNET_break (0); GNUNET_free (plugin); return GNUNET_SYSERR; } address[0] = '\0'; address++; if (GNUNET_OK != GNUNET_STRINGS_to_address_ip (address, strlen (address), &socket_address)) { GNUNET_break (0); GNUNET_free (plugin); return GNUNET_SYSERR; } GNUNET_free(plugin); switch (socket_address.ss_family) { case AF_INET: { struct IPv4XuAddress *u4; const struct sockaddr_in *in4 = (const struct sockaddr_in *) &socket_address; u4 = GNUNET_new (struct IPv4XuAddress); u4->options = htonl (options); u4->ipv4_addr = in4->sin_addr.s_addr; u4->u4_port = in4->sin_port; *buf = u4; *added = sizeof (struct IPv4XuAddress); return GNUNET_OK; } case AF_INET6: { struct IPv6XuAddress *u6; const struct sockaddr_in6 *in6 = (const struct sockaddr_in6 *) &socket_address; u6 = GNUNET_new (struct IPv6XuAddress); u6->options = htonl (options); u6->ipv6_addr = in6->sin6_addr; u6->u6_port = in6->sin6_port; *buf = u6; *added = sizeof (struct IPv6XuAddress); return GNUNET_OK; } default: GNUNET_break (0); return GNUNET_SYSERR; } } /** * Append our port and forward the result. * * @param cls a `struct PrettyPrinterContext *` * @param hostname result from DNS resolver */ static void append_port (void *cls, const char *hostname) { struct PrettyPrinterContext *ppc = cls; struct Plugin *plugin = ppc->plugin; char *ret; if (NULL == hostname) { /* Final call, done */ GNUNET_CONTAINER_DLL_remove (plugin->ppc_dll_head, plugin->ppc_dll_tail, ppc); ppc->resolver_handle = NULL; ppc->asc (ppc->asc_cls, NULL, GNUNET_OK); GNUNET_free (ppc); return; } if (GNUNET_YES == ppc->ipv6) GNUNET_asprintf (&ret, "%s.%u.[%s]:%d", PLUGIN_NAME, ppc->options, hostname, ppc->port); else GNUNET_asprintf (&ret, "%s.%u.%s:%d", PLUGIN_NAME, ppc->options, hostname, ppc->port); ppc->asc (ppc->asc_cls, ret, GNUNET_OK); GNUNET_free (ret); } /** * Convert the transports address to a nice, human-readable format. * * @param cls closure with the `struct Plugin *` * @param type name of the transport that generated the address * @param addr one of the addresses of the host, NULL for the last address * the specific address format depends on the transport; * a `union XuAddress` * @param addrlen length of the address * @param numeric should (IP) addresses be displayed in numeric form? * @param timeout after how long should we give up? * @param asc function to call on each string * @param asc_cls closure for @a asc */ static void xu_plugin_address_pretty_printer (void *cls, const char *type, const void *addr, size_t addrlen, int numeric, struct GNUNET_TIME_Relative timeout, GNUNET_TRANSPORT_AddressStringCallback asc, void *asc_cls) { struct Plugin *plugin = cls; struct PrettyPrinterContext *ppc; const struct sockaddr *sb; size_t sbs; struct sockaddr_in a4; struct sockaddr_in6 a6; const struct IPv4XuAddress *u4; const struct IPv6XuAddress *u6; uint16_t port; uint32_t options; (void) type; if (addrlen == sizeof(struct IPv6XuAddress)) { u6 = addr; memset (&a6, 0, sizeof (a6)); a6.sin6_family = AF_INET6; #if HAVE_SOCKADDR_IN_SIN_LEN a6.sin6_len = sizeof (a6); #endif a6.sin6_port = u6->u6_port; a6.sin6_addr = u6->ipv6_addr; port = ntohs (u6->u6_port); options = ntohl (u6->options); sb = (const struct sockaddr *) &a6; sbs = sizeof (a6); } else if (addrlen == sizeof (struct IPv4XuAddress)) { u4 = addr; memset (&a4, 0, sizeof(a4)); a4.sin_family = AF_INET; #if HAVE_SOCKADDR_IN_SIN_LEN a4.sin_len = sizeof (a4); #endif a4.sin_port = u4->u4_port; a4.sin_addr.s_addr = u4->ipv4_addr; port = ntohs (u4->u4_port); options = ntohl (u4->options); sb = (const struct sockaddr *) &a4; sbs = sizeof(a4); } else { /* invalid address */ GNUNET_break_op (0); asc (asc_cls, NULL, GNUNET_SYSERR); asc (asc_cls, NULL, GNUNET_OK); return; } ppc = GNUNET_new (struct PrettyPrinterContext); ppc->plugin = plugin; ppc->asc = asc; ppc->asc_cls = asc_cls; ppc->port = port; ppc->options = options; if (addrlen == sizeof (struct IPv6XuAddress)) ppc->ipv6 = GNUNET_YES; else ppc->ipv6 = GNUNET_NO; GNUNET_CONTAINER_DLL_insert (plugin->ppc_dll_head, plugin->ppc_dll_tail, ppc); ppc->resolver_handle = GNUNET_RESOLVER_hostname_get (sb, sbs, ! numeric, timeout, &append_port, ppc); } /** * Check if the given port is plausible (must be either our listen * port or our advertised port). If it is neither, we return * #GNUNET_SYSERR. * * @param plugin global variables * @param in_port port number to check * @return #GNUNET_OK if port is either our open or advertised port */ static int check_port (const struct Plugin *plugin, uint16_t in_port) { if ( (plugin->port == in_port) || (plugin->aport == in_port) ) return GNUNET_OK; return GNUNET_SYSERR; } /** * Function that will be called to check if a binary address for this * plugin is well-formed and corresponds to an address for THIS peer * (as per our configuration). Naturally, if absolutely necessary, * plugins can be a bit conservative in their answer, but in general * plugins should make sure that the address does not redirect * traffic to a 3rd party that might try to man-in-the-middle our * traffic. * * @param cls closure, should be our handle to the Plugin * @param addr pointer to a `union XuAddress` * @param addrlen length of @a addr * @return #GNUNET_OK if this is a plausible address for this peer * and transport, #GNUNET_SYSERR if not */ static int xu_plugin_check_address (void *cls, const void *addr, size_t addrlen) { struct Plugin *plugin = cls; const struct IPv4XuAddress *v4; const struct IPv6XuAddress *v6; if (sizeof(struct IPv4XuAddress) == addrlen) { struct sockaddr_in s4; v4 = (const struct IPv4XuAddress *) addr; if (GNUNET_OK != check_port (plugin, ntohs (v4->u4_port))) return GNUNET_SYSERR; memset (&s4, 0, sizeof (s4)); s4.sin_family = AF_INET; #if HAVE_SOCKADDR_IN_SIN_LEN s4.sin_len = sizeof (s4); #endif s4.sin_port = v4->u4_port; s4.sin_addr.s_addr = v4->ipv4_addr; if (GNUNET_OK != GNUNET_NAT_test_address (plugin->nat, &s4, sizeof (struct sockaddr_in))) return GNUNET_SYSERR; } else if (sizeof(struct IPv6XuAddress) == addrlen) { struct sockaddr_in6 s6; v6 = (const struct IPv6XuAddress *) addr; if (IN6_IS_ADDR_LINKLOCAL (&v6->ipv6_addr)) return GNUNET_OK; /* plausible, if unlikely... */ memset (&s6, 0, sizeof (s6)); s6.sin6_family = AF_INET6; #if HAVE_SOCKADDR_IN_SIN_LEN s6.sin6_len = sizeof (s6); #endif s6.sin6_port = v6->u6_port; s6.sin6_addr = v6->ipv6_addr; if (GNUNET_OK != GNUNET_NAT_test_address (plugin->nat, &s6, sizeof(struct sockaddr_in6))) return GNUNET_SYSERR; } else { GNUNET_break_op (0); return GNUNET_SYSERR; } return GNUNET_OK; } /** * Our external IP address/port mapping has changed. * * @param cls closure, the `struct Plugin` * @param add_remove #GNUNET_YES to mean the new public IP address, * #GNUNET_NO to mean the previous (now invalid) one * @param ac address class the address belongs to * @param addr either the previous or the new public IP address * @param addrlen actual length of the @a addr */ static void xu_nat_port_map_callback (void *cls, int add_remove, enum GNUNET_NAT_AddressClass ac, const struct sockaddr *addr, socklen_t addrlen) { struct Plugin *plugin = cls; struct GNUNET_HELLO_Address *address; struct IPv4XuAddress u4; struct IPv6XuAddress u6; void *arg; size_t args; if (GNUNET_NAT_AC_LOOPBACK == ac) return; if (GNUNET_NAT_AC_LAN == ac) return; if (GNUNET_NAT_AC_LAN_PRIVATE == ac) return; LOG (GNUNET_ERROR_TYPE_DEBUG, (GNUNET_YES == add_remove) ? "NAT notification to add address `%s'\n" : "NAT notification to remove address `%s'\n", GNUNET_a2s (addr, addrlen)); /* convert 'address' to our internal format */ switch (addr->sa_family) { case AF_INET: { const struct sockaddr_in *i4; GNUNET_assert (sizeof(struct sockaddr_in) == addrlen); i4 = (const struct sockaddr_in *) addr; if (0 == ntohs (i4->sin_port)) return; /* Port = 0 means unmapped, ignore these for XU. */ memset (&u4, 0, sizeof(u4)); u4.options = htonl (plugin->myoptions); u4.ipv4_addr = i4->sin_addr.s_addr; u4.u4_port = i4->sin_port; arg = &u4; args = sizeof (struct IPv4XuAddress); break; } case AF_INET6: { const struct sockaddr_in6 *i6; GNUNET_assert (sizeof(struct sockaddr_in6) == addrlen); i6 = (const struct sockaddr_in6 *) addr; if (0 == ntohs (i6->sin6_port)) return; /* Port = 0 means unmapped, ignore these for XU. */ memset (&u6, 0, sizeof(u6)); u6.options = htonl (plugin->myoptions); u6.ipv6_addr = i6->sin6_addr; u6.u6_port = i6->sin6_port; arg = &u6; args = sizeof (struct IPv6XuAddress); break; } default: GNUNET_break (0); return; } /* modify our published address list */ /* TODO: use 'ac' here in the future... */ address = GNUNET_HELLO_address_allocate (plugin->env->my_identity, PLUGIN_NAME, arg, args, GNUNET_HELLO_ADDRESS_INFO_NONE); plugin->env->notify_address (plugin->env->cls, add_remove, address); GNUNET_HELLO_address_free (address); } /* ********************* Finding sessions ******************* */ /** * Closure for #session_cmp_it(). */ struct GNUNET_ATS_SessionCompareContext { /** * Set to session matching the address. */ struct GNUNET_ATS_Session *res; /** * Address we are looking for. */ const struct GNUNET_HELLO_Address *address; }; /** * Find a session with a matching address. * * @param cls the `struct GNUNET_ATS_SessionCompareContext *` * @param key peer identity (unused) * @param value the `struct GNUNET_ATS_Session *` * @return #GNUNET_NO if we found the session, #GNUNET_OK if not */ static int session_cmp_it (void *cls, const struct GNUNET_PeerIdentity *key, void *value) { struct GNUNET_ATS_SessionCompareContext *cctx = cls; struct GNUNET_ATS_Session *s = value; (void) key; if (0 == GNUNET_HELLO_address_cmp (s->address, cctx->address)) { GNUNET_assert (GNUNET_NO == s->in_destroy); cctx->res = s; return GNUNET_NO; } return GNUNET_OK; } /** * Locate an existing session the transport service is using to * send data to another peer. Performs some basic sanity checks * on the address and then tries to locate a matching session. * * @param cls the plugin * @param address the address we should locate the session by * @return the session if it exists, or NULL if it is not found */ static struct GNUNET_ATS_Session * xu_plugin_lookup_session (void *cls, const struct GNUNET_HELLO_Address *address) { struct Plugin *plugin = cls; const struct IPv6XuAddress *xu_a6; const struct IPv4XuAddress *xu_a4; struct GNUNET_ATS_SessionCompareContext cctx; if (NULL == address->address) { GNUNET_break (0); return NULL; } if (sizeof(struct IPv4XuAddress) == address->address_length) { if (NULL == plugin->sockv4) return NULL; xu_a4 = (const struct IPv4XuAddress *) address->address; if (0 == xu_a4->u4_port) { GNUNET_break (0); return NULL; } } else if (sizeof(struct IPv6XuAddress) == address->address_length) { if (NULL == plugin->sockv6) return NULL; xu_a6 = (const struct IPv6XuAddress *) address->address; if (0 == xu_a6->u6_port) { GNUNET_break (0); return NULL; } } else { GNUNET_break (0); return NULL; } /* check if session already exists */ cctx.address = address; cctx.res = NULL; LOG (GNUNET_ERROR_TYPE_DEBUG, "Looking for existing session for peer `%s' with address `%s'\n", GNUNET_i2s (&address->peer), xu_address_to_string (plugin, address->address, address->address_length)); GNUNET_CONTAINER_multipeermap_get_multiple (plugin->sessions, &address->peer, &session_cmp_it, &cctx); if (NULL == cctx.res) return NULL; LOG (GNUNET_ERROR_TYPE_DEBUG, "Found existing session %p\n", cctx.res); return cctx.res; } /* ********************** Timeout ****************** */ /** * Increment session timeout due to activity. * * @param s session to reschedule timeout activity for */ static void reschedule_session_timeout (struct GNUNET_ATS_Session *s) { if (GNUNET_YES == s->in_destroy) return; GNUNET_assert (NULL != s->timeout_task); s->timeout = GNUNET_TIME_relative_to_absolute (XU_SESSION_TIME_OUT); } /** * Function that will be called whenever the transport service wants to * notify the plugin that a session is still active and in use and * therefore the session timeout for this session has to be updated * * @param cls closure with the `struct Plugin` * @param peer which peer was the session for * @param session which session is being updated */ static void xu_plugin_update_session_timeout (void *cls, const struct GNUNET_PeerIdentity *peer, struct GNUNET_ATS_Session *session) { struct Plugin *plugin = cls; if (GNUNET_YES != GNUNET_CONTAINER_multipeermap_contains_value (plugin->sessions, peer, session)) { GNUNET_break (0); return; } /* Reschedule session timeout */ reschedule_session_timeout (session); } /* ************************* Sending ************************ */ /** * We failed to transmit a message via XU. Generate * a descriptive error message. * * @param plugin our plugin * @param sa target address we were trying to reach * @param slen number of bytes in @a sa * @param error the errno value returned from the sendto() call */ static void analyze_send_error (struct Plugin *plugin, const struct sockaddr *sa, socklen_t slen, int error) { enum GNUNET_NetworkType type; type = plugin->env->get_address_type (plugin->env->cls, sa, slen); if ( ( (GNUNET_NT_LAN == type) || (GNUNET_NT_WAN == type) ) && ( (ENETUNREACH == errno) || (ENETDOWN == errno) ) ) { if (slen == sizeof (struct sockaddr_in)) { /* IPv4: "Network unreachable" or "Network down" * * This indicates we do not have connectivity */ LOG (GNUNET_ERROR_TYPE_WARNING | GNUNET_ERROR_TYPE_BULK, _("XU could not transmit message to `%s': " "Network seems down, please check your network configuration\n"), GNUNET_a2s (sa, slen)); } if (slen == sizeof (struct sockaddr_in6)) { /* IPv6: "Network unreachable" or "Network down" * * This indicates that this system is IPv6 enabled, but does not * have a valid global IPv6 address assigned or we do not have * connectivity */ LOG (GNUNET_ERROR_TYPE_WARNING | GNUNET_ERROR_TYPE_BULK, _("XU could not transmit IPv6 message! " "Please check your network configuration and disable IPv6 if your " "connection does not have a global IPv6 address\n")); } } else { LOG (GNUNET_ERROR_TYPE_WARNING, "XU could not transmit message to `%s': `%s'\n", GNUNET_a2s (sa, slen), STRERROR (error)); } } /** * Function that can be used by the transport service to transmit a * message using the plugin. Note that in the case of a peer * disconnecting, the continuation MUST be called prior to the * disconnect notification itself. This function will be called with * this peer's HELLO message to initiate a fresh connection to another * peer. * * @param cls closure * @param s which session must be used * @param msgbuf the message to transmit * @param msgbuf_size number of bytes in @a msgbuf * @param priority how important is the message (most plugins will * ignore message priority and just FIFO) * @param to how long to wait at most for the transmission (does not * require plugins to discard the message after the timeout, * just advisory for the desired delay; most plugins will ignore * this as well) * @param cont continuation to call once the message has * been transmitted (or if the transport is ready * for the next transmission call; or if the * peer disconnected...); can be NULL * @param cont_cls closure for @a cont * @return number of bytes used (on the physical network, with overheads); * -1 on hard errors (i.e. address invalid); 0 is a legal value * and does NOT mean that the message was not transmitted (DV) */ static ssize_t xu_plugin_send (void *cls, struct GNUNET_ATS_Session *s, const char *msgbuf, size_t msgbuf_size, unsigned int priority, struct GNUNET_TIME_Relative to, GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls) { struct Plugin *plugin = cls; size_t xumlen = msgbuf_size + sizeof(struct XUMessage); struct XUMessage *xu; char mbuf[xumlen] GNUNET_ALIGN; ssize_t sent; socklen_t slen; const struct sockaddr *a; const struct IPv4XuAddress *u4; struct sockaddr_in a4; const struct IPv6XuAddress *u6; struct sockaddr_in6 a6; struct GNUNET_NETWORK_Handle *sock; (void) priority; (void) to; if ( (sizeof(struct IPv6XuAddress) == s->address->address_length) && (NULL == plugin->sockv6) ) return GNUNET_SYSERR; if ( (sizeof(struct IPv4XuAddress) == s->address->address_length) && (NULL == plugin->sockv4) ) return GNUNET_SYSERR; if (xumlen >= GNUNET_MAX_MESSAGE_SIZE) { GNUNET_break (0); return GNUNET_SYSERR; } if (GNUNET_YES != GNUNET_CONTAINER_multipeermap_contains_value (plugin->sessions, &s->target, s)) { GNUNET_break (0); return GNUNET_SYSERR; } LOG (GNUNET_ERROR_TYPE_DEBUG, "XU transmits %u-byte message to `%s' using address `%s'\n", xumlen, GNUNET_i2s (&s->target), xu_address_to_string (plugin, s->address->address, s->address->address_length)); xu = (struct XUMessage *) mbuf; xu->header.size = htons (xumlen); xu->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_XU_MESSAGE); xu->reserved = htonl (0); xu->sender = *plugin->env->my_identity; GNUNET_memcpy (&xu[1], msgbuf, msgbuf_size); if (sizeof (struct IPv4XuAddress) == s->address->address_length) { u4 = s->address->address; memset (&a4, 0, sizeof(a4)); a4.sin_family = AF_INET; #if HAVE_SOCKADDR_IN_SIN_LEN a4.sin_len = sizeof (a4); #endif a4.sin_port = u4->u4_port; a4.sin_addr.s_addr = u4->ipv4_addr; a = (const struct sockaddr *) &a4; slen = sizeof (a4); sock = plugin->sockv4; } else if (sizeof (struct IPv6XuAddress) == s->address->address_length) { u6 = s->address->address; memset (&a6, 0, sizeof(a6)); a6.sin6_family = AF_INET6; #if HAVE_SOCKADDR_IN_SIN_LEN a6.sin6_len = sizeof (a6); #endif a6.sin6_port = u6->u6_port; a6.sin6_addr = u6->ipv6_addr; a = (const struct sockaddr *) &a6; slen = sizeof (a6); sock = plugin->sockv6; } else { GNUNET_break (0); return GNUNET_SYSERR; } sent = GNUNET_NETWORK_socket_sendto (sock, mbuf, xumlen, a, slen); s->last_transmit_time = GNUNET_TIME_absolute_max (GNUNET_TIME_absolute_get (), s->last_transmit_time); if (GNUNET_SYSERR == sent) { /* Failure */ analyze_send_error (plugin, a, slen, errno); GNUNET_STATISTICS_update (plugin->env->stats, "# XU, total, bytes, sent, failure", sent, GNUNET_NO); GNUNET_STATISTICS_update (plugin->env->stats, "# XU, total, messages, sent, failure", 1, GNUNET_NO); return GNUNET_SYSERR; } /* Success */ LOG (GNUNET_ERROR_TYPE_DEBUG, "XU transmitted %u-byte message to `%s' `%s' (%d: %s)\n", (unsigned int) (msgbuf_size), GNUNET_i2s (&s->target), GNUNET_a2s (a, slen), (int ) sent, (sent < 0) ? STRERROR (errno) : "ok"); GNUNET_STATISTICS_update (plugin->env->stats, "# XU, total, bytes, sent, success", sent, GNUNET_NO); GNUNET_STATISTICS_update (plugin->env->stats, "# XU, total, messages, sent, success", 1, GNUNET_NO); cont (cont_cls, &s->target, GNUNET_OK, msgbuf_size, xumlen); notify_session_monitor (s->plugin, s, GNUNET_TRANSPORT_SS_UPDATE); return xumlen; } /* ********************** Receiving ********************** */ /** * Functions with this signature are called whenever we need to close * a session due to a disconnect or failure to establish a connection. * * @param cls closure with the `struct Plugin` * @param s session to close down * @return #GNUNET_OK on success */ static int xu_disconnect_session (void *cls, struct GNUNET_ATS_Session *s) { struct Plugin *plugin = cls; GNUNET_assert (GNUNET_YES != s->in_destroy); LOG (GNUNET_ERROR_TYPE_DEBUG, "Session %p to peer `%s' at address %s ended\n", s, GNUNET_i2s (&s->target), xu_address_to_string (plugin, s->address->address, s->address->address_length)); if (NULL != s->timeout_task) { GNUNET_SCHEDULER_cancel (s->timeout_task); s->timeout_task = NULL; } GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multipeermap_remove (plugin->sessions, &s->target, s)); s->in_destroy = GNUNET_YES; notify_session_monitor (s->plugin, s, GNUNET_TRANSPORT_SS_DONE); plugin->env->session_end (plugin->env->cls, s->address, s); GNUNET_STATISTICS_set (plugin->env->stats, "# XU sessions active", GNUNET_CONTAINER_multipeermap_size (plugin->sessions), GNUNET_NO); if (0 == s->rc) free_session (s); return GNUNET_OK; } /** * Message tokenizer has broken up an incomming message. Pass it on * to the service. * * @param cls the `struct GNUNET_ATS_Session *` * @param hdr the actual message * @return #GNUNET_OK (always) */ static int process_inbound_tokenized_messages (void *cls, const struct GNUNET_MessageHeader *hdr) { struct GNUNET_ATS_Session *session = cls; struct Plugin *plugin = session->plugin; if (GNUNET_YES == session->in_destroy) return GNUNET_OK; reschedule_session_timeout (session); session->flow_delay_for_other_peer = plugin->env->receive (plugin->env->cls, session->address, session, hdr); return GNUNET_OK; } /** * Destroy a session, plugin is being unloaded. * * @param cls the `struct Plugin` * @param key hash of public key of target peer * @param value a `struct PeerSession *` to clean up * @return #GNUNET_OK (continue to iterate) */ static int disconnect_and_free_it (void *cls, const struct GNUNET_PeerIdentity *key, void *value) { struct Plugin *plugin = cls; (void) key; xu_disconnect_session (plugin, value); return GNUNET_OK; } /** * Disconnect from a remote node. Clean up session if we have one for * this peer. * * @param cls closure for this call (should be handle to Plugin) * @param target the peeridentity of the peer to disconnect * @return #GNUNET_OK on success, #GNUNET_SYSERR if the operation failed */ static void xu_disconnect (void *cls, const struct GNUNET_PeerIdentity *target) { struct Plugin *plugin = cls; LOG (GNUNET_ERROR_TYPE_DEBUG, "Disconnecting from peer `%s'\n", GNUNET_i2s (target)); GNUNET_CONTAINER_multipeermap_get_multiple (plugin->sessions, target, &disconnect_and_free_it, plugin); } /** * Session was idle, so disconnect it. * * @param cls the `struct GNUNET_ATS_Session` to time out */ static void session_timeout (void *cls) { struct GNUNET_ATS_Session *s = cls; struct Plugin *plugin = s->plugin; struct GNUNET_TIME_Relative left; s->timeout_task = NULL; left = GNUNET_TIME_absolute_get_remaining (s->timeout); if (left.rel_value_us > 0) { /* not actually our turn yet, but let's at least update the monitor, it may think we're about to die ... */ notify_session_monitor (s->plugin, s, GNUNET_TRANSPORT_SS_UPDATE); s->timeout_task = GNUNET_SCHEDULER_add_delayed (left, &session_timeout, s); return; } LOG (GNUNET_ERROR_TYPE_DEBUG, "Session %p was idle for %s, disconnecting\n", s, GNUNET_STRINGS_relative_time_to_string (XU_SESSION_TIME_OUT, GNUNET_YES)); /* call session destroy function */ xu_disconnect_session (plugin, s); } /** * Allocate a new session for the given endpoint address. * Note that this function does not inform the service * of the new session, this is the responsibility of the * caller (if needed). * * @param cls the `struct Plugin` * @param address address of the other peer to use * @param network_type network type the address belongs to * @return NULL on error, otherwise session handle */ static struct GNUNET_ATS_Session * xu_plugin_create_session (void *cls, const struct GNUNET_HELLO_Address *address, enum GNUNET_NetworkType network_type) { struct Plugin *plugin = cls; struct GNUNET_ATS_Session *s; s = GNUNET_new (struct GNUNET_ATS_Session); s->mst = GNUNET_MST_create (&process_inbound_tokenized_messages, s); s->plugin = plugin; s->address = GNUNET_HELLO_address_copy (address); s->target = address->peer; s->last_transmit_time = GNUNET_TIME_absolute_get (); s->last_expected_ack_delay = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, 250); s->last_expected_msg_delay = GNUNET_TIME_UNIT_MILLISECONDS; s->flow_delay_from_other_peer = GNUNET_TIME_UNIT_ZERO; s->flow_delay_for_other_peer = GNUNET_TIME_UNIT_ZERO; s->timeout = GNUNET_TIME_relative_to_absolute (XU_SESSION_TIME_OUT); s->timeout_task = GNUNET_SCHEDULER_add_delayed (XU_SESSION_TIME_OUT, &session_timeout, s); s->scope = network_type; LOG (GNUNET_ERROR_TYPE_DEBUG, "Creating new session %p for peer `%s' address `%s'\n", s, GNUNET_i2s (&address->peer), xu_address_to_string (plugin, address->address, address->address_length)); GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_multipeermap_put (plugin->sessions, &s->target, s, GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE)); GNUNET_STATISTICS_set (plugin->env->stats, "# XU sessions active", GNUNET_CONTAINER_multipeermap_size (plugin->sessions), GNUNET_NO); notify_session_monitor (plugin, s, GNUNET_TRANSPORT_SS_INIT); return s; } /** * Creates a new outbound session the transport service will use to * send data to the peer. * * @param cls the `struct Plugin *` * @param address the address * @return the session or NULL of max connections exceeded */ static struct GNUNET_ATS_Session * xu_plugin_get_session (void *cls, const struct GNUNET_HELLO_Address *address) { struct Plugin *plugin = cls; struct GNUNET_ATS_Session *s; enum GNUNET_NetworkType network_type = GNUNET_NT_UNSPECIFIED; const struct IPv4XuAddress *xu_v4; const struct IPv6XuAddress *xu_v6; if (NULL == address) { GNUNET_break (0); return NULL; } if ( (address->address_length != sizeof(struct IPv4XuAddress)) && (address->address_length != sizeof(struct IPv6XuAddress)) ) { GNUNET_break_op (0); return NULL; } if (NULL != (s = xu_plugin_lookup_session (cls, address))) return s; /* need to create new session */ if (sizeof (struct IPv4XuAddress) == address->address_length) { struct sockaddr_in v4; xu_v4 = (const struct IPv4XuAddress *) address->address; memset (&v4, '\0', sizeof (v4)); v4.sin_family = AF_INET; #if HAVE_SOCKADDR_IN_SIN_LEN v4.sin_len = sizeof (struct sockaddr_in); #endif v4.sin_port = xu_v4->u4_port; v4.sin_addr.s_addr = xu_v4->ipv4_addr; network_type = plugin->env->get_address_type (plugin->env->cls, (const struct sockaddr *) &v4, sizeof (v4)); } if (sizeof (struct IPv6XuAddress) == address->address_length) { struct sockaddr_in6 v6; xu_v6 = (const struct IPv6XuAddress *) address->address; memset (&v6, '\0', sizeof (v6)); v6.sin6_family = AF_INET6; #if HAVE_SOCKADDR_IN_SIN_LEN v6.sin6_len = sizeof (struct sockaddr_in6); #endif v6.sin6_port = xu_v6->u6_port; v6.sin6_addr = xu_v6->ipv6_addr; network_type = plugin->env->get_address_type (plugin->env->cls, (const struct sockaddr *) &v6, sizeof (v6)); } GNUNET_break (GNUNET_NT_UNSPECIFIED != network_type); return xu_plugin_create_session (cls, address, network_type); } /** * We've received a XU Message. Process it (pass contents to main service). * * @param plugin plugin context * @param msg the message * @param xu_addr sender address * @param xu_addr_len number of bytes in @a xu_addr * @param network_type network type the address belongs to */ static void process_xu_message (struct Plugin *plugin, const struct XUMessage *msg, const union XuAddress *xu_addr, size_t xu_addr_len, enum GNUNET_NetworkType network_type) { struct GNUNET_ATS_Session *s; struct GNUNET_HELLO_Address *address; GNUNET_break (GNUNET_NT_UNSPECIFIED != network_type); if (0 != ntohl (msg->reserved)) { GNUNET_break_op(0); return; } if (ntohs (msg->header.size) < sizeof(struct GNUNET_MessageHeader) + sizeof(struct XUMessage)) { GNUNET_break_op(0); return; } address = GNUNET_HELLO_address_allocate (&msg->sender, PLUGIN_NAME, xu_addr, xu_addr_len, GNUNET_HELLO_ADDRESS_INFO_NONE); if (NULL == (s = xu_plugin_lookup_session (plugin, address))) { s = xu_plugin_create_session (plugin, address, network_type); plugin->env->session_start (plugin->env->cls, address, s, s->scope); notify_session_monitor (plugin, s, GNUNET_TRANSPORT_SS_UP); } GNUNET_free (address); s->rc++; GNUNET_MST_from_buffer (s->mst, (const char *) &msg[1], ntohs (msg->header.size) - sizeof(struct XUMessage), GNUNET_YES, GNUNET_NO); s->rc--; if ( (0 == s->rc) && (GNUNET_YES == s->in_destroy) ) free_session (s); } /** * Read and process a message from the given socket. * * @param plugin the overall plugin * @param rsock socket to read from */ static void xu_select_read (struct Plugin *plugin, struct GNUNET_NETWORK_Handle *rsock) { socklen_t fromlen; struct sockaddr_storage addr; char buf[65536] GNUNET_ALIGN; ssize_t size; const struct GNUNET_MessageHeader *msg; struct IPv4XuAddress v4; struct IPv6XuAddress v6; const struct sockaddr *sa; const struct sockaddr_in *sa4; const struct sockaddr_in6 *sa6; const union XuAddress *int_addr; size_t int_addr_len; enum GNUNET_NetworkType network_type; fromlen = sizeof (addr); memset (&addr, 0, sizeof(addr)); size = GNUNET_NETWORK_socket_recvfrom (rsock, buf, sizeof (buf), (struct sockaddr *) &addr, &fromlen); sa = (const struct sockaddr *) &addr; #if MINGW /* On SOCK_DGRAM XU sockets recvfrom might fail with a * WSAECONNRESET error to indicate that previous sendto() (yes, sendto!) * on this socket has failed. * Quote from MSDN: * WSAECONNRESET - The virtual circuit was reset by the remote side * executing a hard or abortive close. The application should close * the socket; it is no longer usable. On a XU-datagram socket this * error indicates a previous send operation resulted in an ICMP Port * Unreachable message. */ if ( (-1 == size) && (ECONNRESET == errno) ) return; #endif if (-1 == size) { LOG (GNUNET_ERROR_TYPE_DEBUG, "XU failed to receive data: %s\n", STRERROR (errno)); /* Connection failure or something. Not a protocol violation. */ return; } /* Check if this is a STUN packet */ if (GNUNET_NO != GNUNET_NAT_stun_handle_packet (plugin->nat, (const struct sockaddr *) &addr, fromlen, buf, size)) return; /* was STUN, do not process further */ if (((size_t) size) < sizeof(struct GNUNET_MessageHeader)) { LOG (GNUNET_ERROR_TYPE_WARNING, "XU got %u bytes from %s, which is not enough for a GNUnet message header\n", (unsigned int ) size, GNUNET_a2s (sa, fromlen)); /* _MAY_ be a connection failure (got partial message) */ /* But it _MAY_ also be that the other side uses non-GNUnet protocol. */ GNUNET_break_op (0); return; } msg = (const struct GNUNET_MessageHeader *) buf; LOG (GNUNET_ERROR_TYPE_DEBUG, "XU received %u-byte message from `%s' type %u\n", (unsigned int) size, GNUNET_a2s (sa, fromlen), ntohs (msg->type)); if (size != ntohs (msg->size)) { LOG (GNUNET_ERROR_TYPE_WARNING, "XU malformed message (size %u) header from %s\n", (unsigned int) size, GNUNET_a2s (sa, fromlen)); GNUNET_break_op (0); return; } GNUNET_STATISTICS_update (plugin->env->stats, "# XU, total bytes received", size, GNUNET_NO); network_type = plugin->env->get_address_type (plugin->env->cls, sa, fromlen); switch (sa->sa_family) { case AF_INET: sa4 = (const struct sockaddr_in *) &addr; v4.options = 0; v4.ipv4_addr = sa4->sin_addr.s_addr; v4.u4_port = sa4->sin_port; int_addr = (union XuAddress *) &v4; int_addr_len = sizeof (v4); break; case AF_INET6: sa6 = (const struct sockaddr_in6 *) &addr; v6.options = 0; v6.ipv6_addr = sa6->sin6_addr; v6.u6_port = sa6->sin6_port; int_addr = (union XuAddress *) &v6; int_addr_len = sizeof (v6); break; default: GNUNET_break (0); return; } switch (ntohs (msg->type)) { case GNUNET_MESSAGE_TYPE_TRANSPORT_XU_MESSAGE: if (ntohs (msg->size) < sizeof(struct XUMessage)) { GNUNET_break_op(0); return; } process_xu_message (plugin, (const struct XUMessage *) msg, int_addr, int_addr_len, network_type); return; default: GNUNET_break_op(0); return; } } /* ***************** Event loop (part 2) *************** */ /** * We have been notified that our readset has something to read. We don't * know which socket needs to be read, so we have to check each one * Then reschedule this function to be called again once more is available. * * @param cls the plugin handle */ static void xu_plugin_select_v4 (void *cls) { struct Plugin *plugin = cls; const struct GNUNET_SCHEDULER_TaskContext *tc; plugin->select_task_v4 = NULL; if (NULL == plugin->sockv4) return; tc = GNUNET_SCHEDULER_get_task_context (); if ( (0 != (tc->reason & GNUNET_SCHEDULER_REASON_READ_READY)) && (GNUNET_NETWORK_fdset_isset (tc->read_ready, plugin->sockv4)) ) xu_select_read (plugin, plugin->sockv4); schedule_select_v4 (plugin); } /** * We have been notified that our readset has something to read. We don't * know which socket needs to be read, so we have to check each one * Then reschedule this function to be called again once more is available. * * @param cls the plugin handle */ static void xu_plugin_select_v6 (void *cls) { struct Plugin *plugin = cls; const struct GNUNET_SCHEDULER_TaskContext *tc; plugin->select_task_v6 = NULL; if (NULL == plugin->sockv6) return; tc = GNUNET_SCHEDULER_get_task_context (); if ( (0 != (tc->reason & GNUNET_SCHEDULER_REASON_READ_READY)) && (GNUNET_NETWORK_fdset_isset (tc->read_ready, plugin->sockv6)) ) xu_select_read (plugin, plugin->sockv6); schedule_select_v6 (plugin); } /* ******************* Initialization *************** */ /** * Setup the XU sockets (for IPv4 and IPv6) for the plugin. * * @param plugin the plugin to initialize * @param bind_v6 IPv6 address to bind to (can be NULL, for 'any') * @param bind_v4 IPv4 address to bind to (can be NULL, for 'any') * @return number of sockets that were successfully bound */ static unsigned int setup_sockets (struct Plugin *plugin, const struct sockaddr_in6 *bind_v6, const struct sockaddr_in *bind_v4) { int tries; unsigned int sockets_created = 0; struct sockaddr_in6 server_addrv6; struct sockaddr_in server_addrv4; const struct sockaddr *server_addr; const struct sockaddr *addrs[2]; socklen_t addrlens[2]; socklen_t addrlen; int eno; /* Create IPv6 socket */ eno = EINVAL; if (GNUNET_YES == plugin->enable_ipv6) { plugin->sockv6 = GNUNET_NETWORK_socket_create (PF_INET6, SOCK_DGRAM, 0); if (NULL == plugin->sockv6) { LOG (GNUNET_ERROR_TYPE_INFO, _("Disabling IPv6 since it is not supported on this system!\n")); plugin->enable_ipv6 = GNUNET_NO; } else { memset (&server_addrv6, 0, sizeof(struct sockaddr_in6)); #if HAVE_SOCKADDR_IN_SIN_LEN server_addrv6.sin6_len = sizeof (struct sockaddr_in6); #endif server_addrv6.sin6_family = AF_INET6; if (NULL != bind_v6) server_addrv6.sin6_addr = bind_v6->sin6_addr; else server_addrv6.sin6_addr = in6addr_any; if (0 == plugin->port) /* autodetect */ server_addrv6.sin6_port = htons (GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG, 33537) + 32000); else server_addrv6.sin6_port = htons (plugin->port); addrlen = sizeof (struct sockaddr_in6); server_addr = (const struct sockaddr *) &server_addrv6; tries = 0; while (tries < 10) { LOG(GNUNET_ERROR_TYPE_DEBUG, "Binding to IPv6 `%s'\n", GNUNET_a2s (server_addr, addrlen)); /* binding */ if (GNUNET_OK == GNUNET_NETWORK_socket_bind (plugin->sockv6, server_addr, addrlen)) break; eno = errno; if (0 != plugin->port) { tries = 10; /* fail immediately */ break; /* bind failed on specific port */ } /* autodetect */ server_addrv6.sin6_port = htons (GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG, 33537) + 32000); tries++; } if (tries >= 10) { GNUNET_NETWORK_socket_close (plugin->sockv6); plugin->enable_ipv6 = GNUNET_NO; plugin->sockv6 = NULL; } else { plugin->port = ntohs (server_addrv6.sin6_port); } if (NULL != plugin->sockv6) { LOG (GNUNET_ERROR_TYPE_DEBUG, "IPv6 XU socket created listinging at %s\n", GNUNET_a2s (server_addr, addrlen)); addrs[sockets_created] = server_addr; addrlens[sockets_created] = addrlen; sockets_created++; } else { LOG (GNUNET_ERROR_TYPE_WARNING, _("Failed to bind XU socket to %s: %s\n"), GNUNET_a2s (server_addr, addrlen), STRERROR (eno)); } } } /* Create IPv4 socket */ eno = EINVAL; plugin->sockv4 = GNUNET_NETWORK_socket_create (PF_INET, SOCK_DGRAM, 0); if (NULL == plugin->sockv4) { GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "socket"); LOG (GNUNET_ERROR_TYPE_INFO, _("Disabling IPv4 since it is not supported on this system!\n")); plugin->enable_ipv4 = GNUNET_NO; } else { memset (&server_addrv4, 0, sizeof(struct sockaddr_in)); #if HAVE_SOCKADDR_IN_SIN_LEN server_addrv4.sin_len = sizeof (struct sockaddr_in); #endif server_addrv4.sin_family = AF_INET; if (NULL != bind_v4) server_addrv4.sin_addr = bind_v4->sin_addr; else server_addrv4.sin_addr.s_addr = INADDR_ANY; if (0 == plugin->port) /* autodetect */ server_addrv4.sin_port = htons (GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG, 33537) + 32000); else server_addrv4.sin_port = htons (plugin->port); addrlen = sizeof (struct sockaddr_in); server_addr = (const struct sockaddr *) &server_addrv4; tries = 0; while (tries < 10) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Binding to IPv4 `%s'\n", GNUNET_a2s (server_addr, addrlen)); /* binding */ if (GNUNET_OK == GNUNET_NETWORK_socket_bind (plugin->sockv4, server_addr, addrlen)) break; eno = errno; if (0 != plugin->port) { tries = 10; /* fail */ break; /* bind failed on specific port */ } /* autodetect */ server_addrv4.sin_port = htons (GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG, 33537) + 32000); tries++; } if (tries >= 10) { GNUNET_NETWORK_socket_close (plugin->sockv4); plugin->enable_ipv4 = GNUNET_NO; plugin->sockv4 = NULL; } else { plugin->port = ntohs (server_addrv4.sin_port); } if (NULL != plugin->sockv4) { LOG (GNUNET_ERROR_TYPE_DEBUG, "IPv4 socket created on port %s\n", GNUNET_a2s (server_addr, addrlen)); addrs[sockets_created] = server_addr; addrlens[sockets_created] = addrlen; sockets_created++; } else { LOG (GNUNET_ERROR_TYPE_ERROR, _("Failed to bind XU socket to %s: %s\n"), GNUNET_a2s (server_addr, addrlen), STRERROR (eno)); } } if (0 == sockets_created) { LOG (GNUNET_ERROR_TYPE_WARNING, _("Failed to open XU sockets\n")); return 0; /* No sockets created, return */ } schedule_select_v4 (plugin); schedule_select_v6 (plugin); plugin->nat = GNUNET_NAT_register (plugin->env->cfg, "transport-xu", IPPROTO_UDP, sockets_created, addrs, addrlens, &xu_nat_port_map_callback, NULL, plugin); return sockets_created; } /** * The exported method. Makes the core api available via a global and * returns the xu transport API. * * @param cls our `struct GNUNET_TRANSPORT_PluginEnvironment` * @return our `struct GNUNET_TRANSPORT_PluginFunctions` */ void * libgnunet_plugin_transport_xu_init (void *cls) { struct GNUNET_TRANSPORT_PluginEnvironment *env = cls; struct GNUNET_TRANSPORT_PluginFunctions *api; struct Plugin *p; unsigned long long port; unsigned long long aport; int enable_v6; char *bind4_address; char *bind6_address; struct sockaddr_in server_addrv4; struct sockaddr_in6 server_addrv6; unsigned int res; int have_bind4; int have_bind6; if (NULL == env->receive) { /* run in 'stub' mode (i.e. as part of gnunet-peerinfo), don't fully initialze the plugin or the API */ api = GNUNET_new (struct GNUNET_TRANSPORT_PluginFunctions); api->cls = NULL; api->address_pretty_printer = &xu_plugin_address_pretty_printer; api->address_to_string = &xu_address_to_string; api->string_to_address = &xu_string_to_address; return api; } /* Get port number: port == 0 : autodetect a port, * > 0 : use this port, not given : 2086 default */ if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_number (env->cfg, "transport-xu", "PORT", &port)) port = 2086; if (port > 65535) { GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "transport-xu", "PORT", _("must be in [0,65535]")); return NULL; } if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_number (env->cfg, "transport-xu", "ADVERTISED_PORT", &aport)) aport = port; if (aport > 65535) { GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "transport-xu", "ADVERTISED_PORT", _("must be in [0,65535]")); return NULL; } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (env->cfg, "nat", "DISABLEV6")) enable_v6 = GNUNET_NO; else enable_v6 = GNUNET_YES; have_bind4 = GNUNET_NO; memset (&server_addrv4, 0, sizeof (server_addrv4)); if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_string (env->cfg, "transport-xu", "BINDTO", &bind4_address)) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Binding XU plugin to specific address: `%s'\n", bind4_address); if (1 != inet_pton (AF_INET, bind4_address, &server_addrv4.sin_addr)) { GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "transport-xu", "BINDTO", _("must be valid IPv4 address")); GNUNET_free (bind4_address); return NULL; } have_bind4 = GNUNET_YES; } GNUNET_free_non_null (bind4_address); have_bind6 = GNUNET_NO; memset (&server_addrv6, 0, sizeof (server_addrv6)); if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_string (env->cfg, "transport-xu", "BINDTO6", &bind6_address)) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Binding xu plugin to specific address: `%s'\n", bind6_address); if (1 != inet_pton (AF_INET6, bind6_address, &server_addrv6.sin6_addr)) { GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "transport-xu", "BINDTO6", _("must be valid IPv6 address")); GNUNET_free (bind6_address); return NULL; } have_bind6 = GNUNET_YES; } GNUNET_free_non_null (bind6_address); p = GNUNET_new (struct Plugin); p->port = port; p->aport = aport; p->enable_ipv6 = enable_v6; p->enable_ipv4 = GNUNET_YES; /* default */ p->env = env; p->sessions = GNUNET_CONTAINER_multipeermap_create (16, GNUNET_NO); res = setup_sockets (p, (GNUNET_YES == have_bind6) ? &server_addrv6 : NULL, (GNUNET_YES == have_bind4) ? &server_addrv4 : NULL); if ( (0 == res) || ( (NULL == p->sockv4) && (NULL == p->sockv6) ) ) { LOG (GNUNET_ERROR_TYPE_ERROR, _("Failed to create XU network sockets\n")); GNUNET_CONTAINER_multipeermap_destroy (p->sessions); if (NULL != p->nat) GNUNET_NAT_unregister (p->nat); GNUNET_free (p); return NULL; } api = GNUNET_new (struct GNUNET_TRANSPORT_PluginFunctions); api->cls = p; api->disconnect_session = &xu_disconnect_session; api->query_keepalive_factor = &xu_query_keepalive_factor; api->disconnect_peer = &xu_disconnect; api->address_pretty_printer = &xu_plugin_address_pretty_printer; api->address_to_string = &xu_address_to_string; api->string_to_address = &xu_string_to_address; api->check_address = &xu_plugin_check_address; api->get_session = &xu_plugin_get_session; api->send = &xu_plugin_send; api->get_network = &xu_plugin_get_network; api->get_network_for_address = &xu_plugin_get_network_for_address; api->update_session_timeout = &xu_plugin_update_session_timeout; api->setup_monitor = &xu_plugin_setup_monitor; return api; } /** * The exported method. Makes the core api available via a global and * returns the xu transport API. * * @param cls our `struct GNUNET_TRANSPORT_PluginEnvironment` * @return NULL */ void * libgnunet_plugin_transport_xu_done (void *cls) { struct GNUNET_TRANSPORT_PluginFunctions *api = cls; struct Plugin *plugin = api->cls; struct PrettyPrinterContext *cur; if (NULL == plugin) { GNUNET_free (api); return NULL; } if (NULL != plugin->select_task_v4) { GNUNET_SCHEDULER_cancel (plugin->select_task_v4); plugin->select_task_v4 = NULL; } if (NULL != plugin->select_task_v6) { GNUNET_SCHEDULER_cancel (plugin->select_task_v6); plugin->select_task_v6 = NULL; } if (NULL != plugin->sockv4) { GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (plugin->sockv4)); plugin->sockv4 = NULL; } if (NULL != plugin->sockv6) { GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (plugin->sockv6)); plugin->sockv6 = NULL; } if (NULL != plugin->nat) { GNUNET_NAT_unregister (plugin->nat); plugin->nat = NULL; } GNUNET_CONTAINER_multipeermap_destroy (plugin->sessions); while (NULL != (cur = plugin->ppc_dll_head)) { GNUNET_break (0); GNUNET_CONTAINER_DLL_remove (plugin->ppc_dll_head, plugin->ppc_dll_tail, cur); GNUNET_RESOLVER_request_cancel (cur->resolver_handle); if (NULL != cur->timeout_task) { GNUNET_SCHEDULER_cancel (cur->timeout_task); cur->timeout_task = NULL; } GNUNET_free (cur); } GNUNET_free (plugin); GNUNET_free (api); return NULL; } /* end of plugin_transport_xu.c */