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Diffstat (limited to 'src/transport/plugin_transport_xu.c')
| -rw-r--r-- | src/transport/plugin_transport_xu.c | 2490 |
1 files changed, 2490 insertions, 0 deletions
diff --git a/src/transport/plugin_transport_xu.c b/src/transport/plugin_transport_xu.c new file mode 100644 index 0000000000..59e00f80eb --- /dev/null +++ b/src/transport/plugin_transport_xu.c @@ -0,0 +1,2490 @@ +/* + 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 <http://www.gnu.org/licenses/>. + */ + +/** + * @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_ATS_Network_Type 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_ATS_Network_Type +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_ATS_Network_Type +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_ATS_NET_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_ATS_Network_Type type; + + type = plugin->env->get_address_type (plugin->env->cls, + sa, + slen); + if ( ( (GNUNET_ATS_NET_LAN == type) || + (GNUNET_ATS_NET_WAN == type) ) &&a |