/* This file is part of GNUnet. (C) 2010 Christian Grothoff 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 vpn/gnunet-daemon-vpn-helper.c * @brief * @author Philipp Toelke */ #include #include #include #include #include #include #include #include #include #include #include #include "gnunet-daemon-vpn-dns.h" #include "gnunet-daemon-vpn.h" #include "gnunet-daemon-vpn-helper.h" #include "gnunet-service-dns-p.h" #include "gnunet-vpn-packet.h" #include "gnunet-vpn-checksum.h" #include "gnunet-helper-vpn-api.h" struct GNUNET_VPN_HELPER_Handle *helper_handle; extern struct GNUNET_CLIENT_TransmitHandle *dns_transmit_handle; /** * The tunnels that will be used to send tcp- and udp-packets */ static struct GNUNET_MESH_Tunnel *tcp_tunnel; static struct GNUNET_MESH_Tunnel *udp_tunnel; /** * Start the helper-process * * If cls != NULL it is assumed that this function is called as a result of a dying * helper. cls is then taken as handle to the old helper and is cleaned up. * {{{ */ void start_helper_and_schedule (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { shs_task = GNUNET_SCHEDULER_NO_TASK; if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)) return; if (cls != NULL) cleanup_helper (cls); cls = NULL; char *ifname; char *ipv6addr; char *ipv6prefix; char *ipv4addr; char *ipv4mask; if (GNUNET_SYSERR == GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IFNAME", &ifname)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No entry 'IFNAME' in configuration!\n"); exit (1); } if (GNUNET_SYSERR == GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV6ADDR", &ipv6addr)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No entry 'IPV6ADDR' in configuration!\n"); exit (1); } if (GNUNET_SYSERR == GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV6PREFIX", &ipv6prefix)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No entry 'IPV6PREFIX' in configuration!\n"); exit (1); } if (GNUNET_SYSERR == GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV4ADDR", &ipv4addr)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No entry 'IPV4ADDR' in configuration!\n"); exit (1); } if (GNUNET_SYSERR == GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "IPV4MASK", &ipv4mask)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "No entry 'IPV4MASK' in configuration!\n"); exit (1); } /* Start the helper * Messages get passed to the function message_token * When the helper dies, this function will be called again with the * helper_handle as cls. */ helper_handle = start_helper (ifname, ipv6addr, ipv6prefix, ipv4addr, ipv4mask, "vpn-gnunet", start_helper_and_schedule, message_token, NULL); GNUNET_free (ipv6addr); GNUNET_free (ipv6prefix); GNUNET_free (ipv4addr); GNUNET_free (ipv4mask); GNUNET_free (ifname); /* Tell the dns-service to rehijack the dns-port * The routing-table gets flushed if an interface disappears. */ restart_hijack = 1; if (NULL != dns_connection && dns_transmit_handle == NULL) dns_transmit_handle = GNUNET_CLIENT_notify_transmit_ready (dns_connection, sizeof (struct GNUNET_MessageHeader), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL); GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL, helper_handle->fh_to_helper, &helper_write, NULL); } /*}}}*/ static void * initialize_tunnel_state (int addrlen, struct GNUNET_MESH_TransmitHandle *th) { struct tunnel_state *ts = GNUNET_malloc (sizeof *ts); ts->addrlen = addrlen; ts->th = th; return ts; } /** * Send an dns-answer-packet to the helper */ void helper_write (void *cls __attribute__ ((unused)), const struct GNUNET_SCHEDULER_TaskContext *tsdkctx) { if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) return; struct answer_packet_list *ans = answer_proc_head; if (NULL == ans) return; size_t len = ntohs (ans->pkt.hdr.size); GNUNET_assert (ans->pkt.subtype == GNUNET_DNS_ANSWER_TYPE_IP); GNUNET_assert (20 == sizeof (struct ip_hdr)); GNUNET_assert (8 == sizeof (struct udp_pkt)); size_t data_len = len - sizeof (struct answer_packet) + 1; void *buf; size_t pkt_len; if (ans->pkt.addrlen == 16) { size_t net_len = sizeof (struct ip6_hdr) + sizeof (struct udp_dns) + data_len; pkt_len = sizeof (struct GNUNET_MessageHeader) + sizeof (struct pkt_tun) + net_len; struct ip6_udp_dns *pkt = alloca (pkt_len); GNUNET_assert (pkt != NULL); memset (pkt, 0, pkt_len); /* set the gnunet-header */ pkt->shdr.size = htons (pkt_len); pkt->shdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER); /* set the tun-header (no flags and ethertype of IPv4) */ pkt->tun.flags = 0; pkt->tun.type = htons (0x86dd); memcpy (&pkt->ip6_hdr.sadr, ans->pkt.from, 16); memcpy (&pkt->ip6_hdr.dadr, ans->pkt.to, 16); /* set the udp-header */ pkt->udp_dns.udp_hdr.spt = htons (53); pkt->udp_dns.udp_hdr.dpt = ans->pkt.dst_port; pkt->udp_dns.udp_hdr.len = htons (net_len - sizeof (struct ip6_hdr)); pkt->udp_dns.udp_hdr.crc = 0; uint32_t sum = 0; sum = calculate_checksum_update (sum, (uint16_t *) & pkt->ip6_hdr.sadr, 16); sum = calculate_checksum_update (sum, (uint16_t *) & pkt->ip6_hdr.dadr, 16); uint32_t tmp = (pkt->udp_dns.udp_hdr.len & 0xffff); sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4); tmp = htons (((pkt->ip6_hdr.nxthdr & 0x00ff))); sum = calculate_checksum_update (sum, (uint16_t *) & tmp, 4); sum = calculate_checksum_update (sum, (uint16_t *) & pkt->udp_dns.udp_hdr, ntohs (net_len - sizeof (struct ip6_hdr))); pkt->udp_dns.udp_hdr.crc = calculate_checksum_end (sum); pkt->ip6_hdr.version = 6; pkt->ip6_hdr.paylgth = net_len - sizeof (struct ip6_hdr); pkt->ip6_hdr.nxthdr = IPPROTO_UDP; pkt->ip6_hdr.hoplmt = 0xff; memcpy (&pkt->udp_dns.data, ans->pkt.data, data_len); buf = pkt; } else if (ans->pkt.addrlen == 4) { size_t net_len = sizeof (struct ip_hdr) + sizeof (struct udp_dns) + data_len; pkt_len = sizeof (struct GNUNET_MessageHeader) + sizeof (struct pkt_tun) + net_len; struct ip_udp_dns *pkt = alloca (pkt_len); GNUNET_assert (pkt != NULL); memset (pkt, 0, pkt_len); /* set the gnunet-header */ pkt->shdr.size = htons (pkt_len); pkt->shdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER); /* set the tun-header (no flags and ethertype of IPv4) */ pkt->tun.flags = 0; pkt->tun.type = htons (0x0800); /* set the ip-header */ pkt->ip_hdr.version = 4; pkt->ip_hdr.hdr_lngth = 5; pkt->ip_hdr.diff_serv = 0; pkt->ip_hdr.tot_lngth = htons (net_len); pkt->ip_hdr.ident = 0; pkt->ip_hdr.flags = 0; pkt->ip_hdr.frag_off = 0; pkt->ip_hdr.ttl = 255; pkt->ip_hdr.proto = IPPROTO_UDP; pkt->ip_hdr.chks = 0; /* Will be calculated later */ memcpy (&pkt->ip_hdr.sadr, ans->pkt.from, 4); memcpy (&pkt->ip_hdr.dadr, ans->pkt.to, 4); pkt->ip_hdr.chks = calculate_ip_checksum ((uint16_t *) & pkt->ip_hdr, 5 * 4); /* set the udp-header */ pkt->udp_dns.udp_hdr.spt = htons (53); pkt->udp_dns.udp_hdr.dpt = ans->pkt.dst_port; pkt->udp_dns.udp_hdr.len = htons (net_len - sizeof (struct ip_hdr)); pkt->udp_dns.udp_hdr.crc = 0; /* Optional for IPv4 */ memcpy (&pkt->udp_dns.data, ans->pkt.data, data_len); buf = pkt; } else { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Wrong addrlen = %d\n", ans->pkt.addrlen); GNUNET_assert (0); return; /* convince compiler that we're done here */ } GNUNET_CONTAINER_DLL_remove (answer_proc_head, answer_proc_tail, ans); GNUNET_free (ans); if (GNUNET_DISK_file_write (helper_handle->fh_to_helper, buf, pkt_len) < 0) { cleanup_helper (helper_handle); GNUNET_SCHEDULER_add_now (start_helper_and_schedule, NULL); return; } /* if more packets are available, reschedule */ if (answer_proc_head != NULL) GNUNET_SCHEDULER_add_write_file (GNUNET_TIME_UNIT_FOREVER_REL, helper_handle->fh_to_helper, &helper_write, NULL); } /** * Receive packets from the helper-process */ void message_token (void *cls __attribute__ ((unused)), void *client __attribute__ ((unused)), const struct GNUNET_MessageHeader *message) { GNUNET_assert (ntohs (message->type) == GNUNET_MESSAGE_TYPE_VPN_HELPER); struct tun_pkt *pkt_tun = (struct tun_pkt *) message; GNUNET_HashCode *key; /* ethertype is ipv6 */ if (ntohs (pkt_tun->tun.type) == 0x86dd) { struct ip6_pkt *pkt6 = (struct ip6_pkt *) message; GNUNET_assert (pkt6->ip6_hdr.version == 6); struct ip6_tcp *pkt6_tcp; struct ip6_udp *pkt6_udp; struct ip6_icmp *pkt6_icmp; pkt6_udp = NULL; /* make compiler happy */ switch (pkt6->ip6_hdr.nxthdr) { case IPPROTO_UDP: pkt6_udp = (struct ip6_udp *) pkt6; /* Send dns-packets to the service-dns */ if (ntohs (pkt6_udp->udp_hdr.dpt) == 53) { /* 9 = 8 for the udp-header + 1 for the unsigned char data[1]; */ size_t len = sizeof (struct query_packet) + ntohs (pkt6_udp->udp_hdr.len) - 9; struct query_packet_list *query = GNUNET_malloc (len + sizeof (struct answer_packet_list) - sizeof (struct answer_packet)); query->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_DNS_LOCAL_QUERY_DNS); query->pkt.hdr.size = htons (len); memcpy (query->pkt.orig_to, &pkt6->ip6_hdr.dadr, 16); memcpy (query->pkt.orig_from, &pkt6->ip6_hdr.sadr, 16); query->pkt.addrlen = 16; query->pkt.src_port = pkt6_udp->udp_hdr.spt; memcpy (query->pkt.data, pkt6_udp->data, ntohs (pkt6_udp->udp_hdr.len) - 8); GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, query); GNUNET_assert (head != NULL); if (dns_connection != NULL && dns_transmit_handle == NULL) dns_transmit_handle = GNUNET_CLIENT_notify_transmit_ready (dns_connection, len, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL); break; } /* fall through */ case IPPROTO_TCP: pkt6_tcp = (struct ip6_tcp *) pkt6; if ((key = address6_mapping_exists (pkt6->ip6_hdr.dadr)) != NULL) { struct map_entry *me = GNUNET_CONTAINER_multihashmap_get (hashmap, key); GNUNET_assert (me != NULL); GNUNET_free (key); size_t size = sizeof (struct GNUNET_MESH_Tunnel *) + sizeof (struct GNUNET_MessageHeader) + sizeof (GNUNET_HashCode) + ntohs (pkt6->ip6_hdr.paylgth); struct GNUNET_MESH_Tunnel **cls = GNUNET_malloc (size); struct GNUNET_MessageHeader *hdr = (struct GNUNET_MessageHeader *) (cls + 1); GNUNET_HashCode *hc = (GNUNET_HashCode *) (hdr + 1); hdr->size = htons (sizeof (struct GNUNET_MessageHeader) + sizeof (GNUNET_HashCode) + ntohs (pkt6->ip6_hdr.paylgth)); GNUNET_MESH_ApplicationType app_type = 0; /* fix compiler uninitialized warning... */ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "me->addrlen is %d\n", me->addrlen); if (me->addrlen == 0) { /* This is a mapping to a gnunet-service */ memcpy (hc, &me->desc.service_descriptor, sizeof (GNUNET_HashCode)); if (IPPROTO_UDP == pkt6->ip6_hdr.nxthdr && (me->desc.service_type & htonl (GNUNET_DNS_SERVICE_TYPE_UDP)) && (port_in_ports (me->desc.ports, pkt6_udp->udp_hdr.dpt) || testBit (me->additional_ports, ntohs (pkt6_udp->udp_hdr.dpt)))) { hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_SERVICE_UDP); memcpy (hc + 1, &pkt6_udp->udp_hdr, ntohs (pkt6_udp->udp_hdr.len)); } else if (IPPROTO_TCP == pkt6->ip6_hdr.nxthdr && (me->desc.service_type & htonl (GNUNET_DNS_SERVICE_TYPE_TCP)) && (port_in_ports (me->desc.ports, pkt6_tcp->tcp_hdr.dpt))) { hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_SERVICE_TCP); memcpy (hc + 1, &pkt6_tcp->tcp_hdr, ntohs (pkt6->ip6_hdr.paylgth)); } else { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "pip: %d\n", port_in_ports (me->desc.ports, pkt6_tcp->tcp_hdr.dpt)); GNUNET_assert (0); } if (me->tunnel == NULL && NULL != cls) { *cls = GNUNET_MESH_tunnel_create (mesh_handle, initialize_tunnel_state (16, NULL), &send_pkt_to_peer, NULL, cls); GNUNET_MESH_peer_request_connect_add (*cls, (struct GNUNET_PeerIdentity *) &me->desc.peer); me->tunnel = *cls; } else if (NULL != cls) { *cls = me->tunnel; send_pkt_to_peer (cls, (struct GNUNET_PeerIdentity *) 1, NULL); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Queued to send IPv6 to peer %x, type %d\n", *((unsigned int *) &me->desc.peer), ntohs (hdr->type)); } } else { /* This is a mapping to a "real" address */ struct remote_addr *s = (struct remote_addr *) hc; s->addrlen = me->addrlen; memcpy (s->addr, me->addr, me->addrlen); s->proto = pkt6->ip6_hdr.nxthdr; if (s->proto == IPPROTO_UDP) { hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_REMOTE_UDP); memcpy (hc + 1, &pkt6_udp->udp_hdr, ntohs (pkt6_udp->udp_hdr.len)); app_type = GNUNET_APPLICATION_TYPE_INTERNET_UDP_GATEWAY; if (NULL != udp_tunnel) me->tunnel = udp_tunnel; } else if (s->proto == IPPROTO_TCP) { hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_REMOTE_TCP); memcpy (hc + 1, &pkt6_tcp->tcp_hdr, ntohs (pkt6->ip6_hdr.paylgth)); app_type = GNUNET_APPLICATION_TYPE_INTERNET_TCP_GATEWAY; if (NULL != tcp_tunnel) me->tunnel = tcp_tunnel; } else { GNUNET_assert (0); } if (me->tunnel == NULL && NULL != cls) { *cls = GNUNET_MESH_tunnel_create (mesh_handle, initialize_tunnel_state (16, NULL), &send_pkt_to_peer, NULL, cls); GNUNET_MESH_peer_request_connect_by_type (*cls, app_type); me->tunnel = *cls; if (GNUNET_APPLICATION_TYPE_INTERNET_UDP_GATEWAY == app_type) udp_tunnel = *cls; else if (GNUNET_APPLICATION_TYPE_INTERNET_TCP_GATEWAY == app_type) tcp_tunnel = *cls; } else if (NULL != cls) { *cls = me->tunnel; send_pkt_to_peer (cls, (struct GNUNET_PeerIdentity *) 1, NULL); } } } else { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Packet to %02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x, which has no mapping\n", pkt6->ip6_hdr.dadr[0], pkt6->ip6_hdr.dadr[1], pkt6->ip6_hdr.dadr[2], pkt6->ip6_hdr.dadr[3], pkt6->ip6_hdr.dadr[4], pkt6->ip6_hdr.dadr[5], pkt6->ip6_hdr.dadr[6], pkt6->ip6_hdr.dadr[7], pkt6->ip6_hdr.dadr[8], pkt6->ip6_hdr.dadr[9], pkt6->ip6_hdr.dadr[10], pkt6->ip6_hdr.dadr[11], pkt6->ip6_hdr.dadr[12], pkt6->ip6_hdr.dadr[13], pkt6->ip6_hdr.dadr[14], pkt6->ip6_hdr.dadr[15]); } break; case 0x3a: /* ICMPv6 */ pkt6_icmp = (struct ip6_icmp *) pkt6; /* If this packet is an icmp-echo-request and a mapping exists, answer */ if (pkt6_icmp->icmp_hdr.type == 0x80 && (key = address6_mapping_exists (pkt6->ip6_hdr.dadr)) != NULL) { GNUNET_free (key); pkt6_icmp = GNUNET_malloc (ntohs (pkt6->shdr.size)); memcpy (pkt6_icmp, pkt6, ntohs (pkt6->shdr.size)); GNUNET_SCHEDULER_add_now (&send_icmp6_response, pkt6_icmp); } break; } } /* ethertype is ipv4 */ else if (ntohs (pkt_tun->tun.type) == 0x0800) { struct ip_pkt *pkt = (struct ip_pkt *) message; struct ip_udp *udp = (struct ip_udp *) message; struct ip_tcp *pkt_tcp; struct ip_udp *pkt_udp; struct ip_icmp *pkt_icmp; GNUNET_assert (pkt->ip_hdr.version == 4); /* Send dns-packets to the service-dns */ if (pkt->ip_hdr.proto == IPPROTO_UDP && ntohs (udp->udp_hdr.dpt) == 53) { /* 9 = 8 for the udp-header + 1 for the unsigned char data[1]; */ size_t len = sizeof (struct query_packet) + ntohs (udp->udp_hdr.len) - 9; struct query_packet_list *query = GNUNET_malloc (len + sizeof (struct answer_packet_list) - sizeof (struct answer_packet)); query->pkt.hdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_DNS_LOCAL_QUERY_DNS); query->pkt.hdr.size = htons (len); memcpy (query->pkt.orig_to, &pkt->ip_hdr.dadr, 4); memcpy (query->pkt.orig_from, &pkt->ip_hdr.sadr, 4); query->pkt.addrlen = 4; query->pkt.src_port = udp->udp_hdr.spt; memcpy (query->pkt.data, udp->data, ntohs (udp->udp_hdr.len) - 8); GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, query); GNUNET_assert (head != NULL); if (dns_connection != NULL && dns_transmit_handle == NULL) dns_transmit_handle = GNUNET_CLIENT_notify_transmit_ready (dns_connection, len, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL); } else { uint32_t dadr = pkt->ip_hdr.dadr; unsigned char *c = (unsigned char *) &dadr; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Packet to %d.%d.%d.%d, proto %x\n", c[0], c[1], c[2], c[3], pkt->ip_hdr.proto); switch (pkt->ip_hdr.proto) { case IPPROTO_TCP: case IPPROTO_UDP: pkt_tcp = (struct ip_tcp *) pkt; pkt_udp = (struct ip_udp *) pkt; if ((key = address4_mapping_exists (dadr)) != NULL) { struct map_entry *me = GNUNET_CONTAINER_multihashmap_get (hashmap, key); GNUNET_assert (me != NULL); GNUNET_free (key); size_t size = sizeof (struct GNUNET_MESH_Tunnel *) + sizeof (struct GNUNET_MessageHeader) + sizeof (GNUNET_HashCode) + ntohs (pkt->ip_hdr.tot_lngth) - 4 * pkt->ip_hdr.hdr_lngth; struct GNUNET_MESH_Tunnel **cls = GNUNET_malloc (size); struct GNUNET_MessageHeader *hdr = (struct GNUNET_MessageHeader *) (cls + 1); GNUNET_HashCode *hc = (GNUNET_HashCode *) (hdr + 1); hdr->size = htons (sizeof (struct GNUNET_MessageHeader) + sizeof (GNUNET_HashCode) + ntohs (pkt->ip_hdr.tot_lngth) - 4 * pkt->ip_hdr.hdr_lngth); GNUNET_MESH_ApplicationType app_type; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "me->addrlen is %d\n", me->addrlen); if (me->addrlen == 0) { /* This is a mapping to a gnunet-service */ memcpy (hc, &me->desc.service_descriptor, sizeof (GNUNET_HashCode)); if ((IPPROTO_UDP == pkt->ip_hdr.proto) && (me->desc.service_type & htonl (GNUNET_DNS_SERVICE_TYPE_UDP)) && (port_in_ports (me->desc.ports, pkt_udp->udp_hdr.dpt) || testBit (me->additional_ports, ntohs (pkt_udp->udp_hdr.dpt)))) { hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_SERVICE_UDP); memcpy (hc + 1, &pkt_udp->udp_hdr, ntohs (pkt_udp->udp_hdr.len)); } else if ((IPPROTO_TCP == pkt->ip_hdr.proto) && (me-> desc.service_type & htonl (GNUNET_DNS_SERVICE_TYPE_TCP)) && (port_in_ports (me->desc.ports, pkt_tcp->tcp_hdr.dpt))) { hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_SERVICE_TCP); memcpy (hc + 1, &pkt_tcp->tcp_hdr, ntohs (pkt->ip_hdr.tot_lngth) - 4 * pkt->ip_hdr.hdr_lngth); } if (me->tunnel == NULL && NULL != cls) { *cls = GNUNET_MESH_tunnel_create (mesh_handle, initialize_tunnel_state (4, NULL), send_pkt_to_peer, NULL, cls); GNUNET_MESH_peer_request_connect_add (*cls, (struct GNUNET_PeerIdentity *) &me->desc.peer); me->tunnel = *cls; } else if (NULL != cls) { *cls = me->tunnel; send_pkt_to_peer (cls, (struct GNUNET_PeerIdentity *) 1, NULL); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Queued to send IPv4 to peer %x, type %d\n", *((unsigned int *) &me->desc.peer), ntohs (hdr->type)); } } else { /* This is a mapping to a "real" address */ struct remote_addr *s = (struct remote_addr *) hc; s->addrlen = me->addrlen; memcpy (s->addr, me->addr, me->addrlen); s->proto = pkt->ip_hdr.proto; if (s->proto == IPPROTO_UDP) { hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_REMOTE_UDP); memcpy (hc + 1, &pkt_udp->udp_hdr, ntohs (pkt_udp->udp_hdr.len)); app_type = GNUNET_APPLICATION_TYPE_INTERNET_UDP_GATEWAY; } else if (s->proto == IPPROTO_TCP) { hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_REMOTE_TCP); memcpy (hc + 1, &pkt_tcp->tcp_hdr, ntohs (pkt->ip_hdr.tot_lngth) - 4 * pkt->ip_hdr.hdr_lngth); app_type = GNUNET_APPLICATION_TYPE_INTERNET_TCP_GATEWAY; } else GNUNET_assert (0); if (me->tunnel == NULL && NULL != cls) { *cls = GNUNET_MESH_tunnel_create (mesh_handle, initialize_tunnel_state (4, NULL), send_pkt_to_peer, NULL, cls); GNUNET_MESH_peer_request_connect_by_type (*cls, app_type); me->tunnel = *cls; } else if (NULL != cls) { *cls = me->tunnel; send_pkt_to_peer (cls, (struct GNUNET_PeerIdentity *) 1, NULL); } } } else { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Packet to %x which has no mapping\n", dadr); } break; case 0x01: /* ICMP */ pkt_icmp = (struct ip_icmp *) pkt; if (pkt_icmp->icmp_hdr.type == 0x8 && (key = address4_mapping_exists (dadr)) != NULL) { GNUNET_free (key); pkt_icmp = GNUNET_malloc (ntohs (pkt->shdr.size)); memcpy (pkt_icmp, pkt, ntohs (pkt->shdr.size)); GNUNET_SCHEDULER_add_now (&send_icmp4_response, pkt_icmp); } break; } } } } void write_to_helper (void *buf, size_t len) { (void) GNUNET_DISK_file_write (helper_handle->fh_to_helper, buf, len); } void schedule_helper_write (struct GNUNET_TIME_Relative time, void *cls) { if (GNUNET_SCHEDULER_NO_TASK != shs_task) return; GNUNET_SCHEDULER_add_write_file (time, helper_handle->fh_to_helper, &helper_write, cls); }