From: Matthias Wachs Date: Fri, 21 Oct 2011 21:53:56 +0000 (+0000) Subject: concept for new completely session based udp plugin X-Git-Tag: initial-import-from-subversion-38251~16344 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=ddc17ac9517141ce9b342ddbb10c87ed328da01b;p=oweals%2Fgnunet.git concept for new completely session based udp plugin old plugin required too many dirty hacks to pass required data around --- diff --git a/src/transport/plugin_transport_udp_new.c b/src/transport/plugin_transport_udp_new.c new file mode 100644 index 000000000..325c5d893 --- /dev/null +++ b/src/transport/plugin_transport_udp_new.c @@ -0,0 +1,1449 @@ +/* + This file is part of GNUnet + (C) 2010, 2011 Christian Grothoff (and other contributing authors) + + 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., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. +*/ + +/** + * @file transport/plugin_transport_udp.c + * @brief Implementation of the UDP NAT punching + * transport service + * @author Christian Grothoff + * @author Nathan Evans + */ +#include "platform.h" +#include "gnunet_hello_lib.h" +#include "gnunet_util_lib.h" +#include "gnunet_fragmentation_lib.h" +#include "gnunet_nat_lib.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-udp", __VA_ARGS__) + + +#define DEBUG_UDP GNUNET_EXTRA_LOGGING + +/** + * MTU for fragmentation subsystem. Should be conservative since + * all communicating peers MUST work with this MTU. + */ +#define UDP_MTU 1400 + +/** + * Number of messages we can defragment in parallel. We only really + * defragment 1 message at a time, but if messages get re-ordered, we + * may want to keep knowledge about the previous message to avoid + * discarding the current message in favor of a single fragment of a + * previous message. 3 should be good since we don't expect massive + * message reorderings with UDP. + */ +#define UDP_MAX_MESSAGES_IN_DEFRAG 3 + +/** + * We keep a defragmentation queue per sender address. How many + * sender addresses do we support at the same time? Memory consumption + * is roughly a factor of 32k * UDP_MAX_MESSAGES_IN_DEFRAG times this + * value. (So 128 corresponds to 12 MB and should suffice for + * connecting to roughly 128 peers via UDP). + */ +#define UDP_MAX_SENDER_ADDRESSES_WITH_DEFRAG 128 + + +/** + * UDP Message-Packet header (after defragmentation). + */ +struct UDPMessage +{ + /** + * Message header. + */ + struct GNUNET_MessageHeader header; + + /** + * Always zero for now. + */ + uint32_t reserved; + + /** + * What is the identity of the sender + */ + struct GNUNET_PeerIdentity sender; + +}; + + +/** + * UDP ACK Message-Packet header (after defragmentation). + */ +struct UDP_ACK_Message +{ + /** + * Message header. + */ + struct GNUNET_MessageHeader header; + + /** + * Desired delay for flow control + */ + uint32_t delay; + + /** + * What is the identity of the sender + */ + struct GNUNET_PeerIdentity sender; +}; + + +/** + * Network format for IPv4 addresses. + */ +struct IPv4UdpAddress +{ + /** + * IPv4 address, in network byte order. + */ + uint32_t ipv4_addr GNUNET_PACKED; + + /** + * Port number, in network byte order. + */ + uint16_t u4_port GNUNET_PACKED; +}; + + +/** + * Network format for IPv6 addresses. + */ +struct IPv6UdpAddress +{ + + /** + * IPv6 address. + */ + struct in6_addr ipv6_addr GNUNET_PACKED; + + /** + * Port number, in network byte order. + */ + uint16_t u6_port GNUNET_PACKED; +}; + + +/* Forward definition */ +struct Plugin; + + +/** + * Session with another peer. FIXME: why not make this into + * a regular 'struct Session' and pass it around!? + */ +struct Session +{ + + /** + * Which peer is this session for or from? + */ + struct GNUNET_PeerIdentity target; + + /** + * Pointer to the global plugin struct. + */ + struct Plugin *plugin; + + /** + * Address of the other peer + */ + const struct sockaddr *sock_addr; + + size_t addrlen; + + /** + * Function to call upon completion of the transmission. + */ + GNUNET_TRANSPORT_TransmitContinuation cont; + + /** + * Closure for 'cont'. + */ + void *cont_cls; + + /** + * Current outgoing message to this peer. + */ + struct GNUNET_FRAGMENT_Context *frag; + + /* + * Is this a reliable, bidirectional connection? + * YES if we already received a message with this session + */ + int bidirectional; + + /* + * Task invalidating this session if idle + */ + GNUNET_SCHEDULER_TaskIdentifier invalidation_task; + + /* + * Desired delay for next sending we send to other peer + */ + struct GNUNET_TIME_Relative flow_delay_for_other_peer; + + /* + * Desired delay for next sending we received from other peer + */ + struct GNUNET_TIME_Absolute flow_delay_from_other_peer; +}; + +/** + * Encapsulation of all of the state of the plugin. + */ +struct Plugin +{ + + /** + * Our environment. + */ + struct GNUNET_TRANSPORT_PluginEnvironment *env; + + /** + * Session of peers with whom we are currently connected, + * map of peer identity to 'struct PeerSession'. + */ + struct GNUNET_CONTAINER_MultiHashMap *sessions; + + /** + * Heap with all of our defragmentation activities. + */ + struct GNUNET_CONTAINER_Heap *defrags; + + /** + * ID of select task + */ + GNUNET_SCHEDULER_TaskIdentifier select_task; + + /** + * Tokenizer for inbound messages. + */ + struct GNUNET_SERVER_MessageStreamTokenizer *mst; + + /** + * Bandwidth tracker to limit global UDP traffic. + */ + struct GNUNET_BANDWIDTH_Tracker tracker; + + /** + * Address we were told to bind to exclusively (IPv4). + */ + char *bind4_address; + + /** + * Address we were told to bind to exclusively (IPv6). + */ + char *bind6_address; + + /** + * Handle to NAT traversal support. + */ + struct GNUNET_NAT_Handle *nat; + + /** + * FD Read set + */ + struct GNUNET_NETWORK_FDSet *rs; + + /** + * The read socket for IPv4 + */ + struct GNUNET_NETWORK_Handle *sockv4; + + /** + * The read socket for IPv6 + */ + struct GNUNET_NETWORK_Handle *sockv6; + + /** + * expected delay for ACKs + */ + struct GNUNET_TIME_Relative last_expected_delay; + + /** + * Port we listen on. + */ + uint16_t port; + + /** + * Port we advertise on. + */ + uint16_t aport; + +}; + +int delete_session_iterator (void *cls, + const GNUNET_HashCode * key, + void *value) +{ + struct Session *s = (struct Session *) value; + if (s->invalidation_task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel(s->invalidation_task); + s->invalidation_task = GNUNET_SCHEDULER_NO_TASK; + } + GNUNET_CONTAINER_multihashmap_remove(s->plugin->sessions, key, s); + + GNUNET_free (s); + return GNUNET_YES; +} +/** + * 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 +udp_disconnect (void *cls, const struct GNUNET_PeerIdentity *target) +{ + struct Plugin *plugin = cls; + + GNUNET_CONTAINER_multihashmap_get_multiple(plugin, &target->hashPubKey, &delete_session_iterator, NULL); + +} + + +/** + * Actually send out the message. + * + * @param plugin the plugin + * @param sa the address to send the message to + * @param msg message to transmit + * @return the number of bytes written + */ +static ssize_t +udp_send (struct Plugin *plugin, const struct sockaddr *sa, + const struct GNUNET_MessageHeader *msg) +{ + ssize_t sent; + size_t slen; + + switch (sa->sa_family) + { + case AF_INET: + if (NULL == plugin->sockv4) + return 0; + sent = + GNUNET_NETWORK_socket_sendto (plugin->sockv4, msg, ntohs (msg->size), + sa, slen = sizeof (struct sockaddr_in)); + break; + case AF_INET6: + if (NULL == plugin->sockv6) + return 0; + sent = + GNUNET_NETWORK_socket_sendto (plugin->sockv6, msg, ntohs (msg->size), + sa, slen = sizeof (struct sockaddr_in6)); + break; + default: + GNUNET_break (0); + return 0; + } + if (GNUNET_SYSERR == sent) + { + GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "sendto"); + LOG (GNUNET_ERROR_TYPE_ERROR, + "UDP transmited %u-byte message to %s (%d: %s)\n", + (unsigned int) ntohs (msg->size), GNUNET_a2s (sa, slen), + (int) sent, (sent < 0) ? STRERROR (errno) : "ok"); + + } + LOG (GNUNET_ERROR_TYPE_DEBUG, + "UDP transmited %u-byte message to %s (%d: %s)\n", + (unsigned int) ntohs (msg->size), GNUNET_a2s (sa, slen), + (int) sent, (sent < 0) ? STRERROR (errno) : "ok"); + return sent; +} + + +static struct Session * +create_session (struct Plugin *plugin, const struct GNUNET_PeerIdentity *target, + const void *addr, size_t addrlen, + GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls) +{ + struct Session * s; + const struct IPv4UdpAddress *t4; + const struct IPv6UdpAddress *t6; + struct sockaddr_in *v4; + struct sockaddr_in6 *v6; + size_t len; + + switch (addrlen) + { + case sizeof (struct IPv4UdpAddress): + if (NULL == plugin->sockv4) + { + return NULL; + } + t4 = addr; + s = + GNUNET_malloc (sizeof (struct Session) + + sizeof (struct sockaddr_in)); + len = sizeof (struct sockaddr_in); + v4 = (struct sockaddr_in *) &s[1]; + v4->sin_family = AF_INET; +#if HAVE_SOCKADDR_IN_SIN_LEN + v4->sin_len = sizeof (struct sockaddr_in); +#endif + v4->sin_port = t4->u4_port; + v4->sin_addr.s_addr = t4->ipv4_addr; + break; + case sizeof (struct IPv6UdpAddress): + if (NULL == plugin->sockv6) + { + return NULL; + } + t6 = addr; + s = + GNUNET_malloc (sizeof (struct Session) + + sizeof (struct sockaddr_in6)); + len = sizeof (struct sockaddr_in6); + v6 = (struct sockaddr_in6 *) &s[1]; + v6->sin6_family = AF_INET6; +#if HAVE_SOCKADDR_IN_SIN_LEN + v6->sin6_len = sizeof (struct sockaddr_in6); +#endif + v6->sin6_port = t6->u6_port; + v6->sin6_addr = t6->ipv6_addr; + break; + default: + /* Must have a valid address to send to */ + GNUNET_break_op (0); + return NULL; + } + + s->valid_until = GNUNET_TIME_absolute_get_zero (); + s->flow_delay_for_other_peer = GNUNET_TIME_relative_get_zero (); + s->flow_delay_from_other_peer = GNUNET_TIME_absolute_get_zero (); + s->bidirectional = GNUNET_NO; + s->invalidation_task = GNUNET_SCHEDULER_NO_TASK; + s->addrlen = len; + s->target = *target; + s->plugin = plugin; + s->sock_addr = (const struct sockaddr *) &s[1]; + s->cont = cont; + s->cont_cls = cont_cls; + + return s; +} + +static void +invalidation_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) +{ + struct Session * s = cls; + s->invalidation_task = GNUNET_SCHEDULER_NO_TASK; + LOG (GNUNET_ERROR_TYPE_ERROR, + "Session %X (`%s') is now invalid\n", s, GNUNET_a2s (s->sock_addr,s->addrlen)); + + s->plugin->env->session_end(s->plugin->env->cls, &s->target, s); + GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove(s->plugin->sessions, &s->target.hashPubKey, s)); + GNUNET_free (s); +} + +static const char * +udp_address_to_string (void *cls, const void *addr, size_t addrlen); + +/** + * Function that is called with messages created by the fragmentation + * module. In the case of the 'proc' callback of the + * GNUNET_FRAGMENT_context_create function, this function must + * eventually call 'GNUNET_FRAGMENT_context_transmission_done'. + * + * @param cls closure, the 'struct PeerSession' + * @param msg the message that was created + */ +static void +send_fragment (void *cls, const struct GNUNET_MessageHeader *msg) +{ + struct Session *s = cls; + + udp_send (session->plugin, session->sock_addr, msg); + GNUNET_FRAGMENT_context_transmission_done (session->frag); +} + +/** + * Function that can be used by the transport service to transmit + * a message using the plugin. + * + * @param cls closure + * @param target who should receive this message (ignored by UDP) + * @param msgbuf one or more GNUNET_MessageHeader(s) strung together + * @param msgbuf_size the size of the msgbuf to send + * @param priority how important is the message (ignored by UDP) + * @param timeout when should we time out (give up) if we can not transmit? + * @param session identifier used for this session (NULL for UDP) + * @param addr the addr to send the message to + * @param addrlen the len of addr + * @param force_address not used, we had better have an address to send to + * because we are stateless!! + * @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...) + * @param cont_cls closure for cont + * + * @return the number of bytes written (may return 0 and the message can + * still be transmitted later!) + */ +static ssize_t +udp_plugin_send (void *cls, const struct GNUNET_PeerIdentity *target, + const char *msgbuf, size_t msgbuf_size, unsigned int priority, + struct GNUNET_TIME_Relative timeout, struct Session *session, + const void *addr, size_t addrlen, int force_address, + GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls) +{ + struct Plugin *plugin = cls; + struct Session *s; + const struct IPv4UdpAddress *t4; + const struct IPv6UdpAddress *t6; + size_t mlen = msgbuf_size + sizeof (struct UDPMessage); + char mbuf[mlen]; + struct UDPMessage *udp; + + if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + + LOG (GNUNET_ERROR_TYPE_DEBUG, + "UDP transmits %u-byte message to `%s' using address `%s' session 0x%X mode %i\n", + msgbuf_size, GNUNET_i2s (target), + udp_address_to_string (NULL, addr, addrlen), + session, force_address); + + /* no valid address given */ + if ((addr = NULL) || (addrlen == 0)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + + if (session != NULL) + { + s = find_session (target, addr, addrlen); + if (s != session) + { + /* found a conflicting session for this peer */ + GNUNET_break (0); + return GNUNET_SYSERR; + } + } + else + { + /* use a reliable transmission but no session given */ + if (force_address == GNUNET_SYSERR) + return GNUNET_SYSERR; + /* create new session */ + s = create_session(plugin, target, addr, addrlen, cont, cont_cls); + GNUNET_CONTAINER_multihashmap_put(plugin->sessions, &target->hashPubKey, s, GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE); + /* schedule invalidation task */ + s->invalidation_task = GNUNET_SCHEDULER_add_delayed(GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT, &invalidation_task, NULL); + } + + /* Message */ + udp = (struct UDPMessage *) mbuf; + udp->header.size = htons (mlen); + udp->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_MESSAGE); + udp->reserved = htonl (0); + udp->sender = *plugin->env->my_identity; + memcpy (&udp[1], msgbuf, msgbuf_size); + + struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get(); + if (s->flow_delay_from_other_peer.abs_value > now.abs_value) + { + struct GNUNET_TIME_Relative delta = GNUNET_TIME_absolute_get_difference(now, s->flow_delay_from_other_peer); + LOG (GNUNET_ERROR_TYPE_DEBUG, + "We try to send to early! Should in %llu!\n", delta.rel_value); + } + else + LOG (GNUNET_ERROR_TYPE_DEBUG, "We can send!\n"); + + + /* send without fragmentation */ + if (mlen <= UDP_MTU) + { + mlen = udp_send (plugin, peer_session->sock_addr, &udp->header); + if (cont != NULL) + cont (cont_cls, target, (mlen > 0) ? GNUNET_OK : GNUNET_SYSERR); + GNUNET_free_non_null (peer_session); + } + /* send with fragmentation */ + else + { + s->frag = GNUNET_FRAGMENT_context_create (plugin->env->stats, UDP_MTU, + &plugin->tracker, + plugin->last_expected_delay, + &udp->header, &send_fragment, + s); + } + return mlen; +} + + +/** + * Message tokenizer has broken up an incomming message. Pass it on + * to the service. + * + * @param cls the 'struct Plugin' + * @param client the Session + * @param hdr the actual message + */ +static void +process_inbound_tokenized_messages (void *cls, void *client, + const struct GNUNET_MessageHeader *hdr) +{ + struct Plugin *plugin = cls; + struct Session * s = client; + struct GNUNET_ATS_Information distance; + struct GNUNET_TIME_Relative delay; + + /* setup ATS */ + distance.type = htonl (GNUNET_ATS_QUALITY_NET_DISTANCE); + distance.value = htonl (1); + + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Giving Session %X %s to transport\n", s->session, GNUNET_i2s(&s->target)); + delay = plugin->env->receive (plugin->env->cls, &s->target, hdr, &distance, 1, s, + // FIXME: USE UDP ADDRESSES!!!! + s->sock_addr, s->addrlen); + s->flow_delay_for_other_peer = delay; +} + + +/** + * We've received a UDP Message. Process it (pass contents to main service). + * + * @param plugin plugin context + * @param msg the message + * @param sender_addr sender address + * @param sender_addr_len number of bytes in sender_addr + */ +static void +process_udp_message (struct Plugin *plugin, const struct UDPMessage *msg, + const struct sockaddr *sender_addr, + socklen_t sender_addr_len) +{ + struct IPv4UdpAddress u4; + struct IPv6UdpAddress u6; + const void *arg; + size_t args; + + if (0 != ntohl (msg->reserved)) + { + GNUNET_break_op (0); + return; + } + if (ntohs (msg->header.size) < + sizeof (struct GNUNET_MessageHeader) + sizeof (struct UDPMessage)) + { + GNUNET_break_op (0); + return; + } + + /* convert address */ + switch (sender_addr->sa_family) + { + case AF_INET: + GNUNET_assert (sender_addr_len == sizeof (struct sockaddr_in)); + u4.ipv4_addr = ((struct sockaddr_in *) sender_addr)->sin_addr.s_addr; + u4.u4_port = ((struct sockaddr_in *) sender_addr)->sin_port; + arg = &u4; + args = sizeof (u4); + break; + case AF_INET6: + GNUNET_assert (sender_addr_len == sizeof (struct sockaddr_in6)); + u6.ipv6_addr = ((struct sockaddr_in6 *) sender_addr)->sin6_addr; + u6.u6_port = ((struct sockaddr_in6 *) sender_addr)->sin6_port; + arg = &u6; + args = sizeof (u6); + break; + default: + GNUNET_break (0); + return; + } +#if DEBUG_UDP + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Received message with %u bytes from peer `%s' at `%s'\n", + (unsigned int) ntohs (msg->header.size), + GNUNET_i2s (&msg->sender), GNUNET_a2s (sender_addr, + sender_addr_len)); +#endif + + const struct UDPMessage * udp_msg = (const struct UDPMessage *) msg; + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Lookup inbound UDP sessions for peer `%s' address `%s'\n", + GNUNET_i2s (&udp_msg->sender), + udp_address_to_string(NULL, arg, args)); + + /* create a session for inbound connections */ + struct Session * s = NULL; + s = find_inbound_session (plugin, &udp_msg->sender, sender_addr, sender_addr_len); + + if (s != NULL) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Found existing inbound UDP sessions 0x%X for peer `%s' address `%s'\n", + s, + GNUNET_i2s (&s->target), + udp_address_to_string(NULL, arg, args)); + } + else + { + s = create_session (plugin, &udp_msg->sender, arg, args, NULL, NULL); + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Creating inbound UDP sessions 0x%X for peer `%s' address `%s'\n", + s, + GNUNET_i2s (&s->target), + udp_address_to_string(NULL, arg, args)); + + GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_multihashmap_put (plugin->sessions, + &s->target.hashPubKey, + s, + GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE)); + } + s->valid_until = GNUNET_TIME_absolute_add(GNUNET_TIME_absolute_get(), GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT); + if (s->invalidation_task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel(s->invalidation_task); + s->invalidation_task = GNUNET_SCHEDULER_NO_TASK; + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Rescheduling %X' `%s'\n", + s, udp_address_to_string(NULL, arg, args)); + } + s->invalidation_task = GNUNET_SCHEDULER_add_delayed(GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT, &invalidation_task, s); + /* we received from peer, so session is bidirectional and reliable */ + s->bidirectional = GNUNET_YES; + + GNUNET_SERVER_mst_receive (plugin->mst, &s, (const char *) &msg[1], + ntohs (msg->header.size) - + sizeof (struct UDPMessage), GNUNET_YES, GNUNET_NO); +} + + +/** + * Read and process a message from the given socket. + * + * @param plugin the overall plugin + * @param rsock socket to read from + */ +static void +udp_read (struct Plugin *plugin, struct GNUNET_NETWORK_Handle *rsock) +{ + socklen_t fromlen; + char addr[32]; + char buf[65536]; + ssize_t ret; + const struct GNUNET_MessageHeader *msg; + const struct GNUNET_MessageHeader *ack; + struct Session *peer_session; + const struct UDP_ACK_Message *udp_ack; + struct ReceiveContext *rc; + struct GNUNET_TIME_Absolute now; + struct FindReceiveContext frc; + struct Session * s = NULL; + struct GNUNET_TIME_Relative flow_delay; + + fromlen = sizeof (addr); + memset (&addr, 0, sizeof (addr)); + ret = + GNUNET_NETWORK_socket_recvfrom (rsock, buf, sizeof (buf), + (struct sockaddr *) &addr, &fromlen); + if (ret < sizeof (struct GNUNET_MessageHeader)) + { + GNUNET_break_op (0); + return; + } + msg = (const struct GNUNET_MessageHeader *) buf; + + LOG (GNUNET_ERROR_TYPE_DEBUG, + "UDP received %u-byte message from `%s' type %i\n", (unsigned int) ret, + GNUNET_a2s ((const struct sockaddr *) addr, fromlen), ntohs(msg->type)); + + if (ret != ntohs (msg->size)) + { + GNUNET_break_op (0); + return; + } + + switch (ntohs (msg->type)) + { + case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_MESSAGE: + if (ntohs (msg->size) < sizeof (struct UDPMessage)) + { + GNUNET_break_op (0); + return; + } + process_udp_message (plugin, (const struct UDPMessage *) msg, + (const struct sockaddr *) addr, fromlen); + return; + + case GNUNET_MESSAGE_TYPE_TRANSPORT_UDP_ACK: + if (ntohs (msg->size) < + sizeof (struct UDP_ACK_Message) + sizeof (struct GNUNET_MessageHeader)) + { + GNUNET_break_op (0); + return; + } + udp_ack = (const struct UDP_ACK_Message *) msg; + LOG (GNUNET_ERROR_TYPE_DEBUG, + "UDP processes %u-byte acknowledgement from `%s' at `%s'\n", + (unsigned int) ntohs (msg->size), GNUNET_i2s (&udp->sender), + GNUNET_a2s ((const struct sockaddr *) addr, fromlen)); + + // TODO Guess a session from address, give it defragmenter and check in process_udp if guess was right + s = guess_session (plugin->sessions, addr, addrlen); + if (GNUNET_OK != GNUNET_FRAGMENT_process_ack (peer_session->frag, ack)) + // ... other stuff + return; + + case GNUNET_MESSAGE_TYPE_FRAGMENT: + LOG (GNUNET_ERROR_TYPE_DEBUG, + "UDP processes %u-byte fragment from `%s'\n", + (unsigned int) ntohs (msg->size), + GNUNET_a2s ((const struct sockaddr *) addr, fromlen)); + // TODO Guess a session from address, give it defragmenter and check in process_udp if guess was right + s = guess_session (plugin->sessions, addr, addrlen); + if (GNUNET_OK == GNUNET_DEFRAGMENT_process_fragment (rc->defrag, msg)) + // other stuff + return; + default: + GNUNET_break_op (0); + return; + } +} + + +/** + * We have been notified that our writeset 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 + * @param tc the scheduling context (for rescheduling this function again) + */ +static void +udp_plugin_select (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) +{ + struct Plugin *plugin = cls; + + plugin->select_task = GNUNET_SCHEDULER_NO_TASK; + if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) + return; + if ((NULL != plugin->sockv4) && + (GNUNET_NETWORK_fdset_isset (tc->read_ready, plugin->sockv4))) + udp_read (plugin, plugin->sockv4); + if ((NULL != plugin->sockv6) && + (GNUNET_NETWORK_fdset_isset (tc->read_ready, plugin->sockv6))) + udp_read (plugin, plugin->sockv6); + plugin->select_task = + GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT, + GNUNET_SCHEDULER_NO_TASK, + GNUNET_TIME_UNIT_FOREVER_REL, plugin->rs, + NULL, &udp_plugin_select, plugin); + +} + + +/** + * 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 open_port or adv_port + */ +static int +check_port (struct Plugin *plugin, uint16_t in_port) +{ + if ((in_port == plugin->port) || (in_port == plugin->aport)) + 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 the address + * @param addrlen length of addr + * @return GNUNET_OK if this is a plausible address for this peer + * and transport, GNUNET_SYSERR if not + * + */ +static int +udp_plugin_check_address (void *cls, const void *addr, size_t addrlen) +{ + struct Plugin *plugin = cls; + struct IPv4UdpAddress *v4; + struct IPv6UdpAddress *v6; + + if ((addrlen != sizeof (struct IPv4UdpAddress)) && + (addrlen != sizeof (struct IPv6UdpAddress))) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (addrlen == sizeof (struct IPv4UdpAddress)) + { + v4 = (struct IPv4UdpAddress *) addr; + if (GNUNET_OK != check_port (plugin, ntohs (v4->u4_port))) + return GNUNET_SYSERR; + if (GNUNET_OK != + GNUNET_NAT_test_address (plugin->nat, &v4->ipv4_addr, + sizeof (struct in_addr))) + return GNUNET_SYSERR; + } + else + { + v6 = (struct IPv6UdpAddress *) addr; + if (IN6_IS_ADDR_LINKLOCAL (&v6->ipv6_addr)) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_OK != check_port (plugin, ntohs (v6->u6_port))) + return GNUNET_SYSERR; + if (GNUNET_OK != + GNUNET_NAT_test_address (plugin->nat, &v6->ipv6_addr, + sizeof (struct in6_addr))) + return GNUNET_SYSERR; + } + return GNUNET_OK; +} + + +/** + * 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 + * @param addrlen length of the address + * @return string representing the same address + */ +static const char * +udp_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 IPv4UdpAddress *t4; + const struct IPv6UdpAddress *t6; + int af; + uint16_t port; + + if (addrlen == sizeof (struct IPv6UdpAddress)) + { + t6 = addr; + af = AF_INET6; + port = ntohs (t6->u6_port); + memcpy (&a6, &t6->ipv6_addr, sizeof (a6)); + sb = &a6; + } + else if (addrlen == sizeof (struct IPv4UdpAddress)) + { + t4 = addr; + af = AF_INET; + port = ntohs (t4->u4_port); + memcpy (&a4, &t4->ipv4_addr, sizeof (a4)); + 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", + buf, port); + return rbuf; +} + + +/** + * Closure for 'append_port'. + */ +struct PrettyPrinterContext +{ + /** + * Function to call with the result. + */ + GNUNET_TRANSPORT_AddressStringCallback asc; + + /** + * Clsoure for 'asc'. + */ + void *asc_cls; + + /** + * Port to add after the IP address. + */ + uint16_t port; +}; + + +/** + * 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; + char *ret; + + if (hostname == NULL) + { + ppc->asc (ppc->asc_cls, NULL); + GNUNET_free (ppc); + return; + } + GNUNET_asprintf (&ret, "%s:%d", hostname, ppc->port); + ppc->asc (ppc->asc_cls, ret); + GNUNET_free (ret); +} + + +/** + * Convert the transports address to a nice, human-readable + * format. + * + * @param cls closure + * @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 + * @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 asc + */ +static void +udp_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 PrettyPrinterContext *ppc; + const void *sb; + size_t sbs; + struct sockaddr_in a4; + struct sockaddr_in6 a6; + const struct IPv4UdpAddress *u4; + const struct IPv6UdpAddress *u6; + uint16_t port; + + if (addrlen == sizeof (struct IPv6UdpAddress)) + { + 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; + memcpy (&a6.sin6_addr, &u6->ipv6_addr, sizeof (struct in6_addr)); + port = ntohs (u6->u6_port); + sb = &a6; + sbs = sizeof (a6); + } + else if (addrlen == sizeof (struct IPv4UdpAddress)) + { + 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); + sb = &a4; + sbs = sizeof (a4); + } + else + { + /* invalid address */ + GNUNET_break_op (0); + asc (asc_cls, NULL); + return; + } + ppc = GNUNET_malloc (sizeof (struct PrettyPrinterContext)); + ppc->asc = asc; + ppc->asc_cls = asc_cls; + ppc->port = port; + GNUNET_RESOLVER_hostname_get (sb, sbs, !numeric, timeout, &append_port, ppc); +} + + +/** + * Our external IP address/port mapping has changed. + * + * @param cls closure, the 'struct LocalAddrList' + * @param add_remove GNUNET_YES to mean the new public IP address, GNUNET_NO to mean + * the previous (now invalid) one + * @param addr either the previous or the new public IP address + * @param addrlen actual lenght of the address + */ +static void +udp_nat_port_map_callback (void *cls, int add_remove, + const struct sockaddr *addr, socklen_t addrlen) +{ + struct Plugin *plugin = cls; + struct IPv4UdpAddress u4; + struct IPv6UdpAddress u6; + void *arg; + size_t args; + + /* convert 'addr' to our internal format */ + switch (addr->sa_family) + { + case AF_INET: + GNUNET_assert (addrlen == sizeof (struct sockaddr_in)); + u4.ipv4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr; + u4.u4_port = ((struct sockaddr_in *) addr)->sin_port; + arg = &u4; + args = sizeof (u4); + break; + case AF_INET6: + GNUNET_assert (addrlen == sizeof (struct sockaddr_in6)); + memcpy (&u6.ipv6_addr, &((struct sockaddr_in6 *) addr)->sin6_addr, + sizeof (struct in6_addr)); + u6.u6_port = ((struct sockaddr_in6 *) addr)->sin6_port; + arg = &u6; + args = sizeof (u6); + break; + default: + GNUNET_break (0); + return; + } + /* modify our published address list */ + plugin->env->notify_address (plugin->env->cls, add_remove, arg, args); +} + + +/** + * The exported method. Makes the core api available via a global and + * returns the udp transport API. + * + * @param cls our 'struct GNUNET_TRANSPORT_PluginEnvironment' + * @return our 'struct GNUNET_TRANSPORT_PluginFunctions' + */ +void * +libgnunet_plugin_transport_udp_init (void *cls) +{ + struct GNUNET_TRANSPORT_PluginEnvironment *env = cls; + unsigned long long port; + unsigned long long aport; + struct GNUNET_TRANSPORT_PluginFunctions *api; + struct Plugin *plugin; + int sockets_created; + struct sockaddr_in serverAddrv4; + struct sockaddr_in6 serverAddrv6; + struct sockaddr *serverAddr; + struct sockaddr *addrs[2]; + socklen_t addrlens[2]; + socklen_t addrlen; + unsigned int tries; + unsigned long long udp_max_bps; + + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_number (env->cfg, "transport-udp", "PORT", + &port)) + port = 2086; + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_number (env->cfg, "transport-udp", + "MAX_BPS", &udp_max_bps)) + udp_max_bps = 1024 * 1024 * 50; /* 50 MB/s == infinity for practical purposes */ + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_number (env->cfg, "transport-udp", + "ADVERTISED_PORT", &aport)) + aport = port; + if (port > 65535) + { + LOG (GNUNET_ERROR_TYPE_WARNING, + _("Given `%s' option is out of range: %llu > %u\n"), "PORT", + port, 65535); + return NULL; + } + memset (&serverAddrv6, 0, sizeof (serverAddrv6)); + memset (&serverAddrv4, 0, sizeof (serverAddrv4)); + + plugin = GNUNET_malloc (sizeof (struct Plugin)); + GNUNET_BANDWIDTH_tracker_init (&plugin->tracker, + GNUNET_BANDWIDTH_value_init ((uint32_t) + udp_max_bps), 30); + plugin->last_expected_delay = GNUNET_TIME_UNIT_SECONDS; + plugin->port = port; + plugin->aport = aport; + plugin->env = env; + api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions)); + api->cls = plugin; + + api->send = &udp_plugin_send; + api->disconnect = &udp_disconnect; + api->address_pretty_printer = &udp_plugin_address_pretty_printer; + api->address_to_string = &udp_address_to_string; + api->check_address = &udp_plugin_check_address; + + if (GNUNET_YES == + GNUNET_CONFIGURATION_get_value_string (env->cfg, "transport-udp", + "BINDTO", &plugin->bind4_address)) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Binding udp plugin to specific address: `%s'\n", + plugin->bind4_address); + if (1 != inet_pton (AF_INET, plugin->bind4_address, &serverAddrv4.sin_addr)) + { + GNUNET_free (plugin->bind4_address); + GNUNET_free (plugin); + GNUNET_free (api); + return NULL; + } + } + + if (GNUNET_YES == + GNUNET_CONFIGURATION_get_value_string (env->cfg, "transport-udp", + "BINDTO6", &plugin->bind6_address)) + { + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Binding udp plugin to specific address: `%s'\n", + plugin->bind6_address); + if (1 != + inet_pton (AF_INET6, plugin->bind6_address, &serverAddrv6.sin6_addr)) + { + LOG (GNUNET_ERROR_TYPE_ERROR, _("Invalid IPv6 address: `%s'\n"), + plugin->bind6_address); + GNUNET_free_non_null (plugin->bind4_address); + GNUNET_free (plugin->bind6_address); + GNUNET_free (plugin); + GNUNET_free (api); + return NULL; + } + } + + plugin->defrags = + GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN); + plugin->sessions = + GNUNET_CONTAINER_multihashmap_create (UDP_MAX_SENDER_ADDRESSES_WITH_DEFRAG + * 2); + plugin->inbound_sessions = + GNUNET_CONTAINER_multihashmap_create (UDP_MAX_SENDER_ADDRESSES_WITH_DEFRAG + * 2); + sockets_created = 0; + if ((GNUNET_YES != + GNUNET_CONFIGURATION_get_value_yesno (plugin->env->cfg, "nat", + "DISABLEV6"))) + { + plugin->sockv6 = GNUNET_NETWORK_socket_create (PF_INET6, SOCK_DGRAM, 0); + if (NULL == plugin->sockv6) + { + GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "socket"); + } + else + { +#if HAVE_SOCKADDR_IN_SIN_LEN + serverAddrv6.sin6_len = sizeof (serverAddrv6); +#endif + serverAddrv6.sin6_family = AF_INET6; + serverAddrv6.sin6_addr = in6addr_any; + serverAddrv6.sin6_port = htons (plugin->port); + addrlen = sizeof (serverAddrv6); + serverAddr = (struct sockaddr *) &serverAddrv6; +#if DEBUG_UDP + LOG (GNUNET_ERROR_TYPE_DEBUG, "Binding to IPv6 port %d\n", + ntohs (serverAddrv6.sin6_port)); +#endif + tries = 0; + while (GNUNET_NETWORK_socket_bind (plugin->sockv6, serverAddr, addrlen) != + GNUNET_OK) + { + serverAddrv6.sin6_port = htons (GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG, 33537) + 32000); /* Find a good, non-root port */ +#if DEBUG_UDP + LOG (GNUNET_ERROR_TYPE_DEBUG, + "IPv6 Binding failed, trying new port %d\n", + ntohs (serverAddrv6.sin6_port)); +#endif + tries++; + if (tries > 10) + { + GNUNET_NETWORK_socket_close (plugin->sockv6); + plugin->sockv6 = NULL; + break; + } + } + if (plugin->sockv6 != NULL) + { + addrs[sockets_created] = (struct sockaddr *) &serverAddrv6; + addrlens[sockets_created] = sizeof (serverAddrv6); + sockets_created++; + } + } + } + + plugin->mst = + GNUNET_SERVER_mst_create (&process_inbound_tokenized_messages, plugin); + plugin->sockv4 = GNUNET_NETWORK_socket_create (PF_INET, SOCK_DGRAM, 0); + if (NULL == plugin->sockv4) + { + GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "socket"); + } + else + { +#if HAVE_SOCKADDR_IN_SIN_LEN + serverAddrv4.sin_len = sizeof (serverAddrv4); +#endif + serverAddrv4.sin_family = AF_INET; + serverAddrv4.sin_addr.s_addr = INADDR_ANY; + serverAddrv4.sin_port = htons (plugin->port); + addrlen = sizeof (serverAddrv4); + serverAddr = (struct sockaddr *) &serverAddrv4; +#if DEBUG_UDP + LOG (GNUNET_ERROR_TYPE_DEBUG, "Binding to IPv4 port %d\n", + ntohs (serverAddrv4.sin_port)); +#endif + tries = 0; + while (GNUNET_NETWORK_socket_bind (plugin->sockv4, serverAddr, addrlen) != + GNUNET_OK) + { + serverAddrv4.sin_port = htons (GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG, 33537) + 32000); /* Find a good, non-root port */ +#if DEBUG_UDP + LOG (GNUNET_ERROR_TYPE_DEBUG, + "IPv4 Binding failed, trying new port %d\n", + ntohs (serverAddrv4.sin_port)); +#endif + tries++; + if (tries > 10) + { + GNUNET_NETWORK_socket_close (plugin->sockv4); + plugin->sockv4 = NULL; + break; + } + } + if (plugin->sockv4 != NULL) + { + addrs[sockets_created] = (struct sockaddr *) &serverAddrv4; + addrlens[sockets_created] = sizeof (serverAddrv4); + sockets_created++; + } + } + + plugin->rs = GNUNET_NETWORK_fdset_create (); + GNUNET_NETWORK_fdset_zero (plugin->rs); + if (NULL != plugin->sockv4) + GNUNET_NETWORK_fdset_set (plugin->rs, plugin->sockv4); + if (NULL != plugin->sockv6) + GNUNET_NETWORK_fdset_set (plugin->rs, plugin->sockv6); + + plugin->select_task = + GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT, + GNUNET_SCHEDULER_NO_TASK, + GNUNET_TIME_UNIT_FOREVER_REL, plugin->rs, + NULL, &udp_plugin_select, plugin); + if (sockets_created == 0) + GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("Failed to open UDP sockets\n")); + plugin->nat = + GNUNET_NAT_register (env->cfg, GNUNET_NO, port, sockets_created, + (const struct sockaddr **) addrs, addrlens, + &udp_nat_port_map_callback, NULL, plugin); + return api; +} + +/** + * Shutdown the plugin. + * + * @param cls our 'struct GNUNET_TRANSPORT_PluginFunctions' + * @return NULL + */ +void * +libgnunet_plugin_transport_udp_done (void *cls) +{ + struct GNUNET_TRANSPORT_PluginFunctions *api = cls; + struct Plugin *plugin = api->cls; + struct ReceiveContext *rc; + + /* FIXME: clean up heap and hashmap */ + GNUNET_CONTAINER_multihashmap_iterate (plugin->sessions, &destroy_session, + NULL); + GNUNET_CONTAINER_multihashmap_destroy (plugin->sessions); + plugin->sessions = NULL; + GNUNET_CONTAINER_multihashmap_iterate (plugin->inbound_sessions, &destroy_inbound_session, + NULL); + GNUNET_CONTAINER_multihashmap_destroy (plugin->inbound_sessions); + plugin->inbound_sessions = NULL; + while (NULL != (rc = GNUNET_CONTAINER_heap_remove_root (plugin->defrags))) + { + GNUNET_DEFRAGMENT_context_destroy (rc->defrag); + GNUNET_free (rc); + } + GNUNET_CONTAINER_heap_destroy (plugin->defrags); + + if (plugin->select_task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel (plugin->select_task); + plugin->select_task = GNUNET_SCHEDULER_NO_TASK; + } + if (plugin->sockv4 != NULL) + { + GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (plugin->sockv4)); + plugin->sockv4 = NULL; + } + if (plugin->sockv6 != NULL) + { + GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (plugin->sockv6)); + plugin->sockv6 = NULL; + } + GNUNET_SERVER_mst_destroy (plugin->mst); + GNUNET_NETWORK_fdset_destroy (plugin->rs); + GNUNET_NAT_unregister (plugin->nat); + plugin->nat = NULL; + GNUNET_free (plugin); + GNUNET_free (api); + return NULL; +} + +/* end of plugin_transport_udp.c */