X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Fexit%2Fgnunet-daemon-exit.c;h=92f38665b5e3a1d82b8d4aefb2d3334dc91a0367;hb=a250da032ba65252d9da96e8429b22e265c69980;hp=7201c61ccbfa2b7c450bcc62a8fc9523d18b6344;hpb=a53a186e50dc5c18513b1e10c3c044c4865d5994;p=oweals%2Fgnunet.git diff --git a/src/exit/gnunet-daemon-exit.c b/src/exit/gnunet-daemon-exit.c index 7201c61cc..92f38665b 100644 --- a/src/exit/gnunet-daemon-exit.c +++ b/src/exit/gnunet-daemon-exit.c @@ -39,11 +39,35 @@ #include "gnunet_protocols.h" #include "gnunet_applications.h" #include "gnunet_mesh_service.h" +#include "gnunet_dnsparser_lib.h" +#include "gnunet_dnsstub_lib.h" #include "gnunet_statistics_service.h" #include "gnunet_constants.h" #include "gnunet_tun_lib.h" +#include "gnunet_regex_lib.h" #include "exit.h" +/** + * Maximum path compression length for mesh regex announcing for IPv4 address + * based regex. + */ +#define REGEX_MAX_PATH_LEN_IPV4 4 + +/** + * Maximum path compression length for mesh regex announcing for IPv6 address + * based regex. + */ +#define REGEX_MAX_PATH_LEN_IPV6 8 + + +/** + * Generic logging shorthand + */ +#define LOG(kind, ...) \ + GNUNET_log_from (kind, "exit", __VA_ARGS__); + + + /** * Information about an address. */ @@ -182,43 +206,94 @@ struct TunnelState struct GNUNET_MESH_Tunnel *tunnel; /** - * Heap node for this state in the connections_heap. + * Active tunnel transmission request (or NULL). */ - struct GNUNET_CONTAINER_HeapNode *heap_node; + struct GNUNET_MESH_TransmitHandle *th; /** - * Key this state has in the connections_map. + * GNUNET_NO if this is a tunnel for TCP/UDP, + * GNUNET_YES if this is a tunnel for DNS, + * GNUNET_SYSERR if the tunnel is not yet initialized. */ - GNUNET_HashCode state_key; + int is_dns; - /** - * Associated service record, or NULL for no service. - */ - struct LocalService *serv; + union + { + struct + { - /** - * Head of DLL of messages for this tunnel. - */ - struct TunnelMessageQueue *head; + /** + * Heap node for this state in the connections_heap. + */ + struct GNUNET_CONTAINER_HeapNode *heap_node; + + /** + * Key this state has in the connections_map. + */ + struct GNUNET_HashCode state_key; + + /** + * Associated service record, or NULL for no service. + */ + struct LocalService *serv; + + /** + * Head of DLL of messages for this tunnel. + */ + struct TunnelMessageQueue *head; + + /** + * Tail of DLL of messages for this tunnel. + */ + struct TunnelMessageQueue *tail; + + /** + * Primary redirection information for this connection. + */ + struct RedirectInformation ri; + } tcp_udp; - /** - * Tail of DLL of messages for this tunnel. - */ - struct TunnelMessageQueue *tail; + struct + { - /** - * Active tunnel transmission request (or NULL). - */ - struct GNUNET_MESH_TransmitHandle *th; + /** + * DNS reply ready for transmission. + */ + char *reply; + + /** + * Socket we are using to transmit this request (must match if we receive + * a response). + */ + struct GNUNET_DNSSTUB_RequestSocket *rs; + + /** + * Number of bytes in 'reply'. + */ + size_t reply_length; + + /** + * Original DNS request ID as used by the client. + */ + uint16_t original_id; + + /** + * DNS request ID that we used for forwarding. + */ + uint16_t my_id; + + } dns; - /** - * Primary redirection information for this connection. - */ - struct RedirectInformation ri; + } specifics; }; +/** + * Return value from 'main'. + */ +static int global_ret; + /** * The handle to the configuration used throughout the process */ @@ -232,7 +307,7 @@ static struct GNUNET_HELPER_Handle *helper_handle; /** * Arguments to the exit helper. */ -static char *exit_argv[7]; +static char *exit_argv[8]; /** * IPv6 address of our TUN interface. @@ -254,7 +329,6 @@ static struct in_addr exit_ipv4addr; */ static struct in_addr exit_ipv4mask; - /** * Statistics. */ @@ -279,7 +353,7 @@ static struct GNUNET_CONTAINER_Heap *connections_heap; /** * If there are at least this many connections, old ones will be removed */ -static long long unsigned int max_connections; +static unsigned long long max_connections; /** * This hashmaps saves interesting things about the configured UDP services @@ -291,6 +365,16 @@ static struct GNUNET_CONTAINER_MultiHashMap *udp_services; */ static struct GNUNET_CONTAINER_MultiHashMap *tcp_services; +/** + * Array of all open DNS requests from tunnels. + */ +static struct TunnelState *tunnels[UINT16_MAX + 1]; + +/** + * Handle to the DNS Stub resolver. + */ +static struct GNUNET_DNSSTUB_Context *dnsstub; + /** * Are we an IPv4-exit? */ @@ -312,6 +396,160 @@ static int ipv4_enabled; static int ipv6_enabled; +/** + * We got a reply from DNS for a request of a MESH tunnel. Send it + * via the tunnel (after changing the request ID back). + * + * @param cls the 'struct TunnelState' + * @param size number of bytes available in buf + * @param buf where to copy the reply + * @return number of bytes written to buf + */ +static size_t +transmit_reply_to_mesh (void *cls, + size_t size, + void *buf) +{ + struct TunnelState *ts = cls; + size_t off; + size_t ret; + char *cbuf = buf; + struct GNUNET_MessageHeader hdr; + struct GNUNET_TUN_DnsHeader dns; + + GNUNET_assert (GNUNET_YES == ts->is_dns); + ts->th = NULL; + GNUNET_assert (ts->specifics.dns.reply != NULL); + if (size == 0) + return 0; + ret = sizeof (struct GNUNET_MessageHeader) + ts->specifics.dns.reply_length; + GNUNET_assert (ret <= size); + hdr.size = htons (ret); + hdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_DNS_FROM_INTERNET); + memcpy (&dns, ts->specifics.dns.reply, sizeof (dns)); + dns.id = ts->specifics.dns.original_id; + off = 0; + memcpy (&cbuf[off], &hdr, sizeof (hdr)); + off += sizeof (hdr); + memcpy (&cbuf[off], &dns, sizeof (dns)); + off += sizeof (dns); + memcpy (&cbuf[off], &ts->specifics.dns.reply[sizeof (dns)], ts->specifics.dns.reply_length - sizeof (dns)); + off += ts->specifics.dns.reply_length - sizeof (dns); + GNUNET_free (ts->specifics.dns.reply); + ts->specifics.dns.reply = NULL; + ts->specifics.dns.reply_length = 0; + GNUNET_assert (ret == off); + return ret; +} + + +/** + * Callback called from DNSSTUB resolver when a resolution + * succeeded. + * + * @param cls NULL + * @param rs the socket that received the response + * @param dns the response itself + * @param r number of bytes in dns + */ +static void +process_dns_result (void *cls, + struct GNUNET_DNSSTUB_RequestSocket *rs, + const struct GNUNET_TUN_DnsHeader *dns, + size_t r) +{ + struct TunnelState *ts; + + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Processing DNS result from stub resolver\n"); + GNUNET_assert (NULL == cls); + /* Handle case that this is a reply to a request from a MESH DNS tunnel */ + ts = tunnels[dns->id]; + if ( (NULL == ts) || + (ts->specifics.dns.rs != rs) ) + return; + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Got a response from the stub resolver for DNS request received via MESH!\n"); + tunnels[dns->id] = NULL; + GNUNET_free_non_null (ts->specifics.dns.reply); + ts->specifics.dns.reply = GNUNET_malloc (r); + ts->specifics.dns.reply_length = r; + memcpy (ts->specifics.dns.reply, dns, r); + if (NULL != ts->th) + GNUNET_MESH_notify_transmit_ready_cancel (ts->th); + ts->th = GNUNET_MESH_notify_transmit_ready (ts->tunnel, + GNUNET_NO, + GNUNET_TIME_UNIT_FOREVER_REL, + NULL, + sizeof (struct GNUNET_MessageHeader) + r, + &transmit_reply_to_mesh, + ts); +} + + +/** + * Process a request via mesh to perform a DNS query. + * + * @param cls closure, NULL + * @param tunnel connection to the other end + * @param tunnel_ctx pointer to our 'struct TunnelState *' + * @param sender who sent the message + * @param message the actual message + * @param atsi performance data for the connection + * @return GNUNET_OK to keep the connection open, + * GNUNET_SYSERR to close it (signal serious error) + */ +static int +receive_dns_request (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, + void **tunnel_ctx, + const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED, + const struct GNUNET_MessageHeader *message, + const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED) +{ + struct TunnelState *ts = *tunnel_ctx; + const struct GNUNET_TUN_DnsHeader *dns; + size_t mlen = ntohs (message->size); + size_t dlen = mlen - sizeof (struct GNUNET_MessageHeader); + char buf[dlen] GNUNET_ALIGN; + struct GNUNET_TUN_DnsHeader *dout; + + if (NULL == dnsstub) + return GNUNET_SYSERR; + if (GNUNET_NO == ts->is_dns) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_SYSERR == ts->is_dns) + { + /* tunnel is DNS from now on */ + ts->is_dns = GNUNET_YES; + } + if (dlen < sizeof (struct GNUNET_TUN_DnsHeader)) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + dns = (const struct GNUNET_TUN_DnsHeader *) &message[1]; + ts->specifics.dns.original_id = dns->id; + if (tunnels[ts->specifics.dns.my_id] == ts) + tunnels[ts->specifics.dns.my_id] = NULL; + ts->specifics.dns.my_id = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, + UINT16_MAX + 1); + tunnels[ts->specifics.dns.my_id] = ts; + memcpy (buf, dns, dlen); + dout = (struct GNUNET_TUN_DnsHeader *) buf; + dout->id = ts->specifics.dns.my_id; + ts->specifics.dns.rs = GNUNET_DNSSTUB_resolve2 (dnsstub, + buf, dlen, + &process_dns_result, + NULL); + if (NULL == ts->specifics.dns.rs) + return GNUNET_SYSERR; + return GNUNET_OK; +} + + /** * Given IP information about a connection, calculate the respective * hash we would use for the 'connections_map'. @@ -320,12 +558,12 @@ static int ipv6_enabled; * @param ri information about the connection */ static void -hash_redirect_info (GNUNET_HashCode *hash, +hash_redirect_info (struct GNUNET_HashCode *hash, const struct RedirectInformation *ri) { char *off; - memset (hash, 0, sizeof (GNUNET_HashCode)); + memset (hash, 0, sizeof (struct GNUNET_HashCode)); /* the GNUnet hashmap only uses the first sizeof(unsigned int) of the hash, so we put the IP address in there (and hope for few collisions) */ off = (char*) hash; @@ -384,12 +622,19 @@ get_redirect_state (int af, uint16_t destination_port, const void *local_ip, uint16_t local_port, - GNUNET_HashCode *state_key) + struct GNUNET_HashCode *state_key) { struct RedirectInformation ri; - GNUNET_HashCode key; + struct GNUNET_HashCode key; struct TunnelState *state; + if ( ( (af == AF_INET) && (protocol == IPPROTO_ICMP) ) || + ( (af == AF_INET6) && (protocol == IPPROTO_ICMPV6) ) ) + { + /* ignore ports */ + destination_port = 0; + local_port = 0; + } ri.remote_address.af = af; if (af == AF_INET) ri.remote_address.address.ipv4 = *((struct in_addr*) destination_ip); @@ -413,7 +658,7 @@ get_redirect_state (int af, /* Mark this connection as freshly used */ if (NULL == state_key) GNUNET_CONTAINER_heap_update_cost (connections_heap, - state->heap_node, + state->specifics.tcp_udp.heap_node, GNUNET_TIME_absolute_get ().abs_value); return state; } @@ -425,20 +670,20 @@ get_redirect_state (int af, * * @param service_map map of services (TCP or UDP) * @param desc service descriptor - * @param dpt destination port + * @param destination_port destination port * @return NULL if we are not aware of such a service */ static struct LocalService * find_service (struct GNUNET_CONTAINER_MultiHashMap *service_map, - const GNUNET_HashCode *desc, - uint16_t dpt) + const struct GNUNET_HashCode *desc, + uint16_t destination_port) { - char key[sizeof (GNUNET_HashCode) + sizeof (uint16_t)]; + char key[sizeof (struct GNUNET_HashCode) + sizeof (uint16_t)]; - memcpy (&key[0], &dpt, sizeof (uint16_t)); - memcpy (&key[sizeof(uint16_t)], desc, sizeof (GNUNET_HashCode)); + memcpy (&key[0], &destination_port, sizeof (uint16_t)); + memcpy (&key[sizeof(uint16_t)], desc, sizeof (struct GNUNET_HashCode)); return GNUNET_CONTAINER_multihashmap_get (service_map, - (GNUNET_HashCode *) key); + (struct GNUNET_HashCode *) key); } @@ -452,7 +697,7 @@ find_service (struct GNUNET_CONTAINER_MultiHashMap *service_map, */ static int free_service_record (void *cls, - const GNUNET_HashCode *key, + const struct GNUNET_HashCode *key, void *value) { struct LocalService *service = value; @@ -469,33 +714,33 @@ free_service_record (void *cls, * * @param service_map map of services (TCP or UDP) * @param name name of the service - * @param dpt destination port + * @param destination_port destination port * @param service service information record to store (service->name will be set). */ static void store_service (struct GNUNET_CONTAINER_MultiHashMap *service_map, const char *name, - uint16_t dpt, + uint16_t destination_port, struct LocalService *service) { - char key[sizeof (GNUNET_HashCode) + sizeof (uint16_t)]; - GNUNET_HashCode desc; + char key[sizeof (struct GNUNET_HashCode) + sizeof (uint16_t)]; + struct GNUNET_HashCode desc; GNUNET_CRYPTO_hash (name, strlen (name) + 1, &desc); service->name = GNUNET_strdup (name); - memcpy (&key[0], &dpt, sizeof (uint16_t)); - memcpy (&key[sizeof(uint16_t)], &desc, sizeof (GNUNET_HashCode)); + memcpy (&key[0], &destination_port, sizeof (uint16_t)); + memcpy (&key[sizeof(uint16_t)], &desc, sizeof (struct GNUNET_HashCode)); if (GNUNET_OK != GNUNET_CONTAINER_multihashmap_put (service_map, - (GNUNET_HashCode *) key, + (struct GNUNET_HashCode *) key, service, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)) { - free_service_record (NULL, (GNUNET_HashCode *) key, service); + free_service_record (NULL, (struct GNUNET_HashCode *) key, service); GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("Got duplicate service records for `%s:%u'\n"), name, - (unsigned int) dpt); + (unsigned int) destination_port); } } @@ -516,18 +761,30 @@ send_to_peer_notify_callback (void *cls, size_t size, void *buf) struct TunnelMessageQueue *tnq; s->th = NULL; - tnq = s->head; + tnq = s->specifics.tcp_udp.head; + if (NULL == tnq) + return 0; + if (0 == size) + { + s->th = GNUNET_MESH_notify_transmit_ready (tunnel, + GNUNET_NO /* corking */, + GNUNET_TIME_UNIT_FOREVER_REL, + NULL, + tnq->len, + &send_to_peer_notify_callback, + s); + return 0; + } GNUNET_assert (size >= tnq->len); memcpy (buf, tnq->payload, tnq->len); size = tnq->len; - GNUNET_CONTAINER_DLL_remove (s->head, - s->tail, + GNUNET_CONTAINER_DLL_remove (s->specifics.tcp_udp.head, + s->specifics.tcp_udp.tail, tnq); GNUNET_free (tnq); - if (NULL != (tnq = s->head)) + if (NULL != (tnq = s->specifics.tcp_udp.head)) s->th = GNUNET_MESH_notify_transmit_ready (tunnel, GNUNET_NO /* corking */, - 0 /* priority */, GNUNET_TIME_UNIT_FOREVER_REL, NULL, tnq->len, @@ -554,9 +811,10 @@ send_packet_to_mesh_tunnel (struct GNUNET_MESH_Tunnel *mesh_tunnel, s = GNUNET_MESH_tunnel_get_data (mesh_tunnel); GNUNET_assert (NULL != s); - GNUNET_CONTAINER_DLL_insert_tail (s->head, s->tail, tnq); + GNUNET_CONTAINER_DLL_insert_tail (s->specifics.tcp_udp.head, s->specifics.tcp_udp.tail, tnq); if (NULL == s->th) - s->th = GNUNET_MESH_notify_transmit_ready (mesh_tunnel, GNUNET_NO /* cork */, 0 /* priority */, + s->th = GNUNET_MESH_notify_transmit_ready (mesh_tunnel, + GNUNET_NO /* cork */, GNUNET_TIME_UNIT_FOREVER_REL, NULL, tnq->len, &send_to_peer_notify_callback, @@ -589,8 +847,8 @@ icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp, const struct GNUNET_TUN_IPv6Header *ipv6; const struct GNUNET_TUN_UdpHeader *udp; size_t mlen; - uint16_t spt; - uint16_t dpt; + uint16_t source_port; + uint16_t destination_port; uint8_t protocol; { @@ -602,7 +860,7 @@ icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp, source_ip, sbuf, sizeof (sbuf)), inet_ntop (af, - source_ip, + destination_ip, dbuf, sizeof (dbuf))); } if (pktlen < sizeof (struct GNUNET_TUN_IcmpHeader)) @@ -615,12 +873,12 @@ icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp, /* Find out if this is an ICMP packet in response to an existing TCP/UDP packet and if so, figure out ports / protocol of the existing session from the IP data in the ICMP payload */ - spt = 0; - dpt = 0; - protocol = IPPROTO_ICMP; + source_port = 0; + destination_port = 0; switch (af) { case AF_INET: + protocol = IPPROTO_ICMP; switch (icmp->type) { case GNUNET_TUN_ICMPTYPE_ECHO_REPLY: @@ -642,17 +900,21 @@ icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp, /* could be TCP or UDP, but both have the ports in the right place, so that doesn't matter here */ udp = (const struct GNUNET_TUN_UdpHeader *) &ipv4[1]; - spt = ntohs (udp->spt); - dpt = ntohs (udp->dpt); + /* swap ports, as they are from the original message */ + destination_port = ntohs (udp->source_port); + source_port = ntohs (udp->destination_port); + /* throw away ICMP payload, won't be useful for the other side anyway */ + pktlen = sizeof (struct GNUNET_TUN_IcmpHeader); break; default: GNUNET_STATISTICS_update (stats, - gettext_noop ("# ICMP packets dropped (not allowed)"), + gettext_noop ("# ICMPv4 packets dropped (type not allowed)"), 1, GNUNET_NO); return; } break; case AF_INET6: + protocol = IPPROTO_ICMPV6; switch (icmp->type) { case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE: @@ -672,15 +934,18 @@ icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp, /* could be TCP or UDP, but both have the ports in the right place, so that doesn't matter here */ udp = (const struct GNUNET_TUN_UdpHeader *) &ipv6[1]; - spt = ntohs (udp->spt); - dpt = ntohs (udp->dpt); + /* swap ports, as they are from the original message */ + destination_port = ntohs (udp->source_port); + source_port = ntohs (udp->destination_port); + /* throw away ICMP payload, won't be useful for the other side anyway */ + pktlen = sizeof (struct GNUNET_TUN_IcmpHeader); break; case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST: case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY: break; default: GNUNET_STATISTICS_update (stats, - gettext_noop ("# ICMP packets dropped (not allowed)"), + gettext_noop ("# ICMPv6 packets dropped (type not allowed)"), 1, GNUNET_NO); return; } @@ -696,20 +961,26 @@ icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp, destination_ip, 0, NULL); break; + case IPPROTO_ICMPV6: + state = get_redirect_state (af, IPPROTO_ICMPV6, + source_ip, 0, + destination_ip, 0, + NULL); + break; case IPPROTO_UDP: state = get_redirect_state (af, IPPROTO_UDP, source_ip, - spt, + source_port, destination_ip, - dpt, + destination_port, NULL); break; case IPPROTO_TCP: state = get_redirect_state (af, IPPROTO_TCP, source_ip, - spt, + source_port, destination_ip, - dpt, + destination_port, NULL); break; default: @@ -721,7 +992,7 @@ icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp, if (NULL == state) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, - _("Packet dropped, have no matching connection information\n")); + _("ICMP Packet dropped, have no matching connection information\n")); return; } mlen = sizeof (struct GNUNET_EXIT_IcmpToVPNMessage) + pktlen - sizeof (struct GNUNET_TUN_IcmpHeader); @@ -735,12 +1006,6 @@ icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp, memcpy (&i2v->icmp_header, icmp, pktlen); - /* FIXME: should we sanitize the host-specific payload here? On the - one hand, quite a bit of what we send is meaningless on the other - side (our IPs, ports, etc.); on the other hand, trying to compact - the packet would be very messy, and blanking fields out is also - hardly productive as they seem to contain nothing remotely - sensitive. */ send_packet_to_mesh_tunnel (state->tunnel, tnq); } @@ -777,11 +1042,11 @@ udp_from_helper (const struct GNUNET_TUN_UdpHeader *udp, inet_ntop (af, source_ip, sbuf, sizeof (sbuf)), - (unsigned int) ntohs (udp->spt), + (unsigned int) ntohs (udp->source_port), inet_ntop (af, - source_ip, + destination_ip, dbuf, sizeof (dbuf)), - (unsigned int) ntohs (udp->dpt)); + (unsigned int) ntohs (udp->destination_port)); } if (pktlen < sizeof (struct GNUNET_TUN_UdpHeader)) { @@ -797,14 +1062,14 @@ udp_from_helper (const struct GNUNET_TUN_UdpHeader *udp, } state = get_redirect_state (af, IPPROTO_UDP, source_ip, - ntohs (udp->spt), + ntohs (udp->source_port), destination_ip, - ntohs (udp->dpt), + ntohs (udp->destination_port), NULL); if (NULL == state) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, - _("Packet dropped, have no matching connection information\n")); + _("UDP Packet dropped, have no matching connection information\n")); return; } mlen = sizeof (struct GNUNET_EXIT_UdpReplyMessage) + pktlen - sizeof (struct GNUNET_TUN_UdpHeader); @@ -843,7 +1108,7 @@ tcp_from_helper (const struct GNUNET_TUN_TcpHeader *tcp, const void *source_ip) { struct TunnelState *state; - char buf[pktlen]; + char buf[pktlen] GNUNET_ALIGN; struct GNUNET_TUN_TcpHeader *mtcp; struct GNUNET_EXIT_TcpDataMessage *tdm; struct TunnelMessageQueue *tnq; @@ -858,11 +1123,11 @@ tcp_from_helper (const struct GNUNET_TUN_TcpHeader *tcp, inet_ntop (af, source_ip, sbuf, sizeof (sbuf)), - (unsigned int) ntohs (tcp->spt), + (unsigned int) ntohs (tcp->source_port), inet_ntop (af, destination_ip, dbuf, sizeof (dbuf)), - (unsigned int) ntohs (tcp->dpt)); + (unsigned int) ntohs (tcp->destination_port)); } if (pktlen < sizeof (struct GNUNET_TUN_TcpHeader)) { @@ -872,14 +1137,14 @@ tcp_from_helper (const struct GNUNET_TUN_TcpHeader *tcp, } state = get_redirect_state (af, IPPROTO_TCP, source_ip, - ntohs (tcp->spt), + ntohs (tcp->source_port), destination_ip, - ntohs (tcp->dpt), + ntohs (tcp->destination_port), NULL); if (NULL == state) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, - _("Packet dropped, have no matching connection information\n")); + _("TCP Packet dropped, have no matching connection information\n")); return; } @@ -887,8 +1152,8 @@ tcp_from_helper (const struct GNUNET_TUN_TcpHeader *tcp, sender will need to lookup the correct values anyway */ memcpy (buf, tcp, pktlen); mtcp = (struct GNUNET_TUN_TcpHeader *) buf; - mtcp->spt = 0; - mtcp->dpt = 0; + mtcp->source_port = 0; + mtcp->destination_port = 0; mtcp->crc = 0; mlen = sizeof (struct GNUNET_EXIT_TcpDataMessage) + (pktlen - sizeof (struct GNUNET_TUN_TcpHeader)); @@ -920,7 +1185,7 @@ tcp_from_helper (const struct GNUNET_TUN_TcpHeader *tcp, * @param client unsued * @param message message received from helper */ -static void +static int message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED, const struct GNUNET_MessageHeader *message) { @@ -937,13 +1202,13 @@ message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED, if (ntohs (message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER) { GNUNET_break (0); - return; + return GNUNET_OK; } size = ntohs (message->size); if (size < sizeof (struct GNUNET_TUN_Layer2PacketHeader) + sizeof (struct GNUNET_MessageHeader)) { GNUNET_break (0); - return; + return GNUNET_OK; } GNUNET_STATISTICS_update (stats, gettext_noop ("# Bytes received from TUN"), @@ -960,20 +1225,20 @@ message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED, { /* Kernel to blame? */ GNUNET_break (0); - return; + return GNUNET_OK; } pkt4 = (const struct GNUNET_TUN_IPv4Header *) &pkt_tun[1]; if (size != ntohs (pkt4->total_length)) { /* Kernel to blame? */ GNUNET_break (0); - return; + return GNUNET_OK; } if (pkt4->header_length * 4 != sizeof (struct GNUNET_TUN_IPv4Header)) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("IPv4 packet options received. Ignored.\n")); - return; + return GNUNET_OK; } size -= sizeof (struct GNUNET_TUN_IPv4Header); @@ -984,6 +1249,7 @@ message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED, AF_INET, &pkt4->destination_address, &pkt4->source_address); + break; case IPPROTO_TCP: tcp_from_helper ((const struct GNUNET_TUN_TcpHeader *) &pkt4[1], size, AF_INET, @@ -998,8 +1264,9 @@ message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED, break; default: GNUNET_log (GNUNET_ERROR_TYPE_WARNING, - _("IPv4 packet with unsupported next header received. Ignored.\n")); - return; + _("IPv4 packet with unsupported next header %u received. Ignored.\n"), + (int) pkt4->protocol); + return GNUNET_OK; } } break; @@ -1011,14 +1278,14 @@ message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED, { /* Kernel to blame? */ GNUNET_break (0); - return; + return GNUNET_OK; } pkt6 = (struct GNUNET_TUN_IPv6Header *) &pkt_tun[1]; - if (size != ntohs (pkt6->payload_length)) + if (size != ntohs (pkt6->payload_length) + sizeof (struct GNUNET_TUN_IPv6Header)) { /* Kernel to blame? */ GNUNET_break (0); - return; + return GNUNET_OK; } size -= sizeof (struct GNUNET_TUN_IPv6Header); switch (pkt6->next_header) @@ -1035,7 +1302,7 @@ message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED, &pkt6->destination_address, &pkt6->source_address); break; - case IPPROTO_ICMP: + case IPPROTO_ICMPV6: icmp_from_helper ((const struct GNUNET_TUN_IcmpHeader *) &pkt6[1], size, AF_INET6, &pkt6->destination_address, @@ -1043,8 +1310,9 @@ message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED, break; default: GNUNET_log (GNUNET_ERROR_TYPE_WARNING, - _("IPv6 packet with unsupported next header received. Ignored.\n")); - return; + _("IPv6 packet with unsupported next header %d received. Ignored.\n"), + pkt6->next_header); + return GNUNET_OK; } } break; @@ -1054,6 +1322,7 @@ message_token (void *cls GNUNET_UNUSED, void *client GNUNET_UNUSED, ntohs (pkt_tun->proto)); break; } + return GNUNET_OK; } @@ -1074,9 +1343,13 @@ setup_fresh_address (int af, local_address->proto = (uint8_t) proto; /* default "local" port range is often 32768--61000, so we pick a random value in that range */ - local_address->port - = (uint16_t) 32768 + GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, - 28232); + if ( ( (af == AF_INET) && (proto == IPPROTO_ICMP) ) || + ( (af == AF_INET6) && (proto == IPPROTO_ICMPV6) ) ) + local_address->port = 0; + else + local_address->port + = (uint16_t) 32768 + GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, + 28232); switch (af) { case AF_INET: @@ -1125,7 +1398,7 @@ setup_fresh_address (int af, /* Given ABCD::/96, we want a mask of 'ABCD::FFFF:FFFF, thus: */ mask = addr; - for (i=127;i>=128-ipv6prefix;i--) + for (i=127;i>=ipv6prefix;i--) mask.s6_addr[i / 8] |= (1 << (i % 8)); /* Pick random IPv6 address within the subnet, except 'addr' or 'mask' itself */ @@ -1166,7 +1439,7 @@ setup_fresh_address (int af, * cleaning up 'old' states. * * @param state skeleton state to setup a record for; should - * 'state->ri.remote_address' filled in so that + * 'state->specifics.tcp_udp.ri.remote_address' filled in so that * this code can determine which AF/protocol is * going to be used (the 'tunnel' should also * already be set); after calling this function, @@ -1177,53 +1450,53 @@ setup_fresh_address (int af, static void setup_state_record (struct TunnelState *state) { - GNUNET_HashCode key; + struct GNUNET_HashCode key; struct TunnelState *s; /* generate fresh, unique address */ do { - if (NULL == state->serv) - setup_fresh_address (state->ri.remote_address.af, - state->ri.remote_address.proto, - &state->ri.local_address); + if (NULL == state->specifics.tcp_udp.serv) + setup_fresh_address (state->specifics.tcp_udp.ri.remote_address.af, + state->specifics.tcp_udp.ri.remote_address.proto, + &state->specifics.tcp_udp.ri.local_address); else - setup_fresh_address (state->serv->address.af, - state->serv->address.proto, - &state->ri.local_address); - } while (NULL != get_redirect_state (state->ri.remote_address.af, - state->ri.remote_address.proto, - &state->ri.remote_address.address, - state->ri.remote_address.port, - &state->ri.local_address.address, - state->ri.local_address.port, + setup_fresh_address (state->specifics.tcp_udp.serv->address.af, + state->specifics.tcp_udp.serv->address.proto, + &state->specifics.tcp_udp.ri.local_address); + } while (NULL != get_redirect_state (state->specifics.tcp_udp.ri.remote_address.af, + state->specifics.tcp_udp.ri.remote_address.proto, + &state->specifics.tcp_udp.ri.remote_address.address, + state->specifics.tcp_udp.ri.remote_address.port, + &state->specifics.tcp_udp.ri.local_address.address, + state->specifics.tcp_udp.ri.local_address.port, &key)); { char buf[INET6_ADDRSTRLEN]; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Picked local address %s:%u for new connection\n", - inet_ntop (state->ri.local_address.af, - &state->ri.local_address.address, + inet_ntop (state->specifics.tcp_udp.ri.local_address.af, + &state->specifics.tcp_udp.ri.local_address.address, buf, sizeof (buf)), - (unsigned int) state->ri.local_address.port); + (unsigned int) state->specifics.tcp_udp.ri.local_address.port); } - state->state_key = key; + state->specifics.tcp_udp.state_key = key; GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_multihashmap_put (connections_map, &key, state, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)); - state->heap_node = GNUNET_CONTAINER_heap_insert (connections_heap, + state->specifics.tcp_udp.heap_node = GNUNET_CONTAINER_heap_insert (connections_heap, state, GNUNET_TIME_absolute_get ().abs_value); while (GNUNET_CONTAINER_heap_get_size (connections_heap) > max_connections) { s = GNUNET_CONTAINER_heap_remove_root (connections_heap); GNUNET_assert (state != s); - s->heap_node = NULL; + s->specifics.tcp_udp.heap_node = NULL; GNUNET_MESH_tunnel_destroy (s->tunnel); GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_multihashmap_remove (connections_map, - &s->state_key, + &s->specifics.tcp_udp.state_key, s)); GNUNET_free (s); } @@ -1241,9 +1514,10 @@ setup_state_record (struct TunnelState *state) * TCP header, depending on protocol) * @param payload_length number of bytes in 'payload' * @param protocol IPPROTO_UDP or IPPROTO_TCP + * @param tcp_header skeleton of the TCP header, NULL for UDP * @param src_address source address to use (IP and port) * @param dst_address destination address to use (IP and port) - * @param pkt6 where to write the assembled packet; must + * @param pkt4 where to write the assembled packet; must * contain enough space for the IP header, UDP/TCP header * AND the payload */ @@ -1288,8 +1562,8 @@ prepare_ipv4_packet (const void *payload, size_t payload_length, { struct GNUNET_TUN_UdpHeader *pkt4_udp = (struct GNUNET_TUN_UdpHeader *) &pkt4[1]; - pkt4_udp->spt = htons (src_address->port); - pkt4_udp->dpt = htons (dst_address->port); + pkt4_udp->source_port = htons (src_address->port); + pkt4_udp->destination_port = htons (dst_address->port); pkt4_udp->len = htons ((uint16_t) payload_length); GNUNET_TUN_calculate_udp4_checksum (pkt4, pkt4_udp, @@ -1301,9 +1575,9 @@ prepare_ipv4_packet (const void *payload, size_t payload_length, { struct GNUNET_TUN_TcpHeader *pkt4_tcp = (struct GNUNET_TUN_TcpHeader *) &pkt4[1]; - memcpy (pkt4_tcp, tcp_header, sizeof (struct GNUNET_TUN_TcpHeader)); - pkt4_tcp->spt = htons (src_address->port); - pkt4_tcp->dpt = htons (dst_address->port); + *pkt4_tcp = *tcp_header; + pkt4_tcp->source_port = htons (src_address->port); + pkt4_tcp->destination_port = htons (dst_address->port); GNUNET_TUN_calculate_tcp4_checksum (pkt4, pkt4_tcp, payload, @@ -1328,6 +1602,7 @@ prepare_ipv4_packet (const void *payload, size_t payload_length, * TCP header, depending on protocol) * @param payload_length number of bytes in 'payload' * @param protocol IPPROTO_UDP or IPPROTO_TCP + * @param tcp_header skeleton TCP header data to send, NULL for UDP * @param src_address source address to use (IP and port) * @param dst_address destination address to use (IP and port) * @param pkt6 where to write the assembled packet; must @@ -1351,12 +1626,7 @@ prepare_ipv6_packet (const void *payload, size_t payload_length, len += sizeof (struct GNUNET_TUN_UdpHeader); break; case IPPROTO_TCP: - /* tcp_header (with port/crc not set) must be part of payload! */ - if (len < sizeof (struct GNUNET_TUN_TcpHeader)) - { - GNUNET_break (0); - return; - } + len += sizeof (struct GNUNET_TUN_TcpHeader); break; default: GNUNET_break (0); @@ -1370,9 +1640,9 @@ prepare_ipv6_packet (const void *payload, size_t payload_length, GNUNET_TUN_initialize_ipv6_header (pkt6, protocol, - len, - &dst_address->address.ipv6, - &src_address->address.ipv6); + len, + &src_address->address.ipv6, + &dst_address->address.ipv6); switch (protocol) { @@ -1380,29 +1650,29 @@ prepare_ipv6_packet (const void *payload, size_t payload_length, { struct GNUNET_TUN_UdpHeader *pkt6_udp = (struct GNUNET_TUN_UdpHeader *) &pkt6[1]; - pkt6_udp->spt = htons (src_address->port); - pkt6_udp->dpt = htons (dst_address->port); + pkt6_udp->source_port = htons (src_address->port); + pkt6_udp->destination_port = htons (dst_address->port); pkt6_udp->len = htons ((uint16_t) payload_length); - pkt6_udp->crc = 0; GNUNET_TUN_calculate_udp6_checksum (pkt6, pkt6_udp, payload, payload_length); - memcpy (&pkt6[1], payload, payload_length); + memcpy (&pkt6_udp[1], payload, payload_length); } break; case IPPROTO_TCP: { - struct GNUNET_TUN_TcpHeader *pkt6_tcp = (struct GNUNET_TUN_TcpHeader *) pkt6; + struct GNUNET_TUN_TcpHeader *pkt6_tcp = (struct GNUNET_TUN_TcpHeader *) &pkt6[1]; /* memcpy first here as some TCP header fields are initialized this way! */ - memcpy (pkt6_tcp, payload, payload_length); - pkt6_tcp->spt = htons (src_address->port); - pkt6_tcp->dpt = htons (dst_address->port); + *pkt6_tcp = *tcp_header; + pkt6_tcp->source_port = htons (src_address->port); + pkt6_tcp->destination_port = htons (dst_address->port); GNUNET_TUN_calculate_tcp6_checksum (pkt6, pkt6_tcp, payload, payload_length); + memcpy (&pkt6_tcp[1], payload, payload_length); } break; default: @@ -1417,7 +1687,7 @@ prepare_ipv6_packet (const void *payload, size_t payload_length, * * @param destination_address IP and port to use for the TCP packet's destination * @param source_address IP and port to use for the TCP packet's source - * @param tcp header template to use + * @param tcp_header header template to use * @param payload payload of the TCP packet * @param payload_length number of bytes in 'payload' */ @@ -1456,7 +1726,7 @@ send_tcp_packet_via_tun (const struct SocketAddress *destination_address, return; } { - char buf[len]; + char buf[len] GNUNET_ALIGN; struct GNUNET_MessageHeader *hdr; struct GNUNET_TUN_Layer2PacketHeader *tun; @@ -1497,10 +1767,11 @@ send_tcp_packet_via_tun (const struct SocketAddress *destination_address, GNUNET_assert (0); break; } - (void) GNUNET_HELPER_send (helper_handle, - (const struct GNUNET_MessageHeader*) buf, - GNUNET_YES, - NULL, NULL); + if (NULL != helper_handle) + (void) GNUNET_HELPER_send (helper_handle, + (const struct GNUNET_MessageHeader*) buf, + GNUNET_YES, + NULL, NULL); } } @@ -1519,7 +1790,7 @@ send_tcp_packet_via_tun (const struct SocketAddress *destination_address, * GNUNET_SYSERR to close it (signal serious error) */ static int -receive_tcp_service (void *unused GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, +receive_tcp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, void **tunnel_ctx GNUNET_UNUSED, const struct GNUNET_PeerIdentity *sender GNUNET_UNUSED, const struct GNUNET_MessageHeader *message, @@ -1529,6 +1800,16 @@ receive_tcp_service (void *unused GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunn const struct GNUNET_EXIT_TcpServiceStartMessage *start; uint16_t pkt_len = ntohs (message->size); + if (GNUNET_YES == state->is_dns) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_SYSERR == state->is_dns) + { + /* tunnel is UDP/TCP from now on */ + state->is_dns = GNUNET_NO; + } GNUNET_STATISTICS_update (stats, gettext_noop ("# TCP service creation requests received via mesh"), 1, GNUNET_NO); @@ -1544,8 +1825,13 @@ receive_tcp_service (void *unused GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunn start = (const struct GNUNET_EXIT_TcpServiceStartMessage*) message; pkt_len -= sizeof (struct GNUNET_EXIT_TcpServiceStartMessage); if ( (NULL == state) || - (NULL != state->serv) || - (NULL != state->heap_node) ) + (NULL != state->specifics.tcp_udp.serv) || + (NULL != state->specifics.tcp_udp.heap_node) ) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (start->tcp_header.off * 4 < sizeof (struct GNUNET_TUN_TcpHeader)) { GNUNET_break_op (0); return GNUNET_SYSERR; @@ -1556,23 +1842,23 @@ receive_tcp_service (void *unused GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunn "Received data from %s for forwarding to TCP service %s on port %u\n", GNUNET_i2s (sender), GNUNET_h2s (&start->service_descriptor), - (unsigned int) ntohs (start->tcp_header.dpt)); - if (NULL == (state->serv = find_service (tcp_services, &start->service_descriptor, - ntohs (start->tcp_header.dpt)))) + (unsigned int) ntohs (start->tcp_header.destination_port)); + if (NULL == (state->specifics.tcp_udp.serv = find_service (tcp_services, &start->service_descriptor, + ntohs (start->tcp_header.destination_port)))) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("No service found for %s on port %d!\n"), "TCP", - ntohs (start->tcp_header.dpt)); + ntohs (start->tcp_header.destination_port)); GNUNET_STATISTICS_update (stats, gettext_noop ("# TCP requests dropped (no such service)"), 1, GNUNET_NO); return GNUNET_SYSERR; } - state->ri.remote_address = state->serv->address; + state->specifics.tcp_udp.ri.remote_address = state->specifics.tcp_udp.serv->address; setup_state_record (state); - send_tcp_packet_via_tun (&state->ri.remote_address, - &state->ri.local_address, + send_tcp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, + &state->specifics.tcp_udp.ri.local_address, &start->tcp_header, &start[1], pkt_len); return GNUNET_YES; @@ -1606,6 +1892,16 @@ receive_tcp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, const void *payload; int af; + if (GNUNET_YES == state->is_dns) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_SYSERR == state->is_dns) + { + /* tunnel is UDP/TCP from now on */ + state->is_dns = GNUNET_NO; + } GNUNET_STATISTICS_update (stats, gettext_noop ("# Bytes received from MESH"), pkt_len, GNUNET_NO); @@ -1620,14 +1916,19 @@ receive_tcp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, start = (const struct GNUNET_EXIT_TcpInternetStartMessage*) message; pkt_len -= sizeof (struct GNUNET_EXIT_TcpInternetStartMessage); if ( (NULL == state) || - (NULL != state->serv) || - (NULL != state->heap_node) ) + (NULL != state->specifics.tcp_udp.serv) || + (NULL != state->specifics.tcp_udp.heap_node) ) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (start->tcp_header.off * 4 < sizeof (struct GNUNET_TUN_TcpHeader)) { GNUNET_break_op (0); return GNUNET_SYSERR; } af = (int) ntohl (start->af); - state->ri.remote_address.af = af; + state->specifics.tcp_udp.ri.remote_address.af = af; switch (af) { case AF_INET: @@ -1644,7 +1945,7 @@ receive_tcp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, v4 = (const struct in_addr*) &start[1]; payload = &v4[1]; pkt_len -= sizeof (struct in_addr); - state->ri.remote_address.address.ipv4 = *v4; + state->specifics.tcp_udp.ri.remote_address.address.ipv4 = *v4; break; case AF_INET6: if (pkt_len < sizeof (struct in6_addr)) @@ -1660,7 +1961,7 @@ receive_tcp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, v6 = (const struct in6_addr*) &start[1]; payload = &v6[1]; pkt_len -= sizeof (struct in6_addr); - state->ri.remote_address.address.ipv6 = *v6; + state->specifics.tcp_udp.ri.remote_address.address.ipv6 = *v6; break; default: GNUNET_break_op (0); @@ -1672,16 +1973,15 @@ receive_tcp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, "Received data from %s for starting TCP stream to %s:%u\n", GNUNET_i2s (sender), inet_ntop (af, - &state->ri.remote_address.address, + &state->specifics.tcp_udp.ri.remote_address.address, buf, sizeof (buf)), - (unsigned int) ntohs (start->tcp_header.dpt)); + (unsigned int) ntohs (start->tcp_header.destination_port)); } - - state->ri.remote_address.proto = IPPROTO_TCP; - state->ri.remote_address.port = ntohs (start->tcp_header.dpt); + state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_TCP; + state->specifics.tcp_udp.ri.remote_address.port = ntohs (start->tcp_header.destination_port); setup_state_record (state); - send_tcp_packet_via_tun (&state->ri.remote_address, - &state->ri.local_address, + send_tcp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, + &state->specifics.tcp_udp.ri.local_address, &start->tcp_header, payload, pkt_len); return GNUNET_YES; @@ -1712,6 +2012,16 @@ receive_tcp_data (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, const struct GNUNET_EXIT_TcpDataMessage *data; uint16_t pkt_len = ntohs (message->size); + if (GNUNET_YES == state->is_dns) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_SYSERR == state->is_dns) + { + /* tunnel is UDP/TCP from now on */ + state->is_dns = GNUNET_NO; + } GNUNET_STATISTICS_update (stats, gettext_noop ("# Bytes received from MESH"), pkt_len, GNUNET_NO); @@ -1726,7 +2036,7 @@ receive_tcp_data (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, data = (const struct GNUNET_EXIT_TcpDataMessage*) message; pkt_len -= sizeof (struct GNUNET_EXIT_TcpDataMessage); if ( (NULL == state) || - (NULL == state->heap_node) ) + (NULL == state->specifics.tcp_udp.heap_node) ) { /* connection should have been up! */ GNUNET_STATISTICS_update (stats, @@ -1734,6 +2044,12 @@ receive_tcp_data (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, 1, GNUNET_NO); return GNUNET_SYSERR; } + if (data->tcp_header.off * 4 < sizeof (struct GNUNET_TUN_TcpHeader)) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + GNUNET_break_op (ntohl (data->reserved) == 0); { char buf[INET6_ADDRSTRLEN]; @@ -1741,14 +2057,14 @@ receive_tcp_data (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, "Received additional %u bytes of data from %s for TCP stream to %s:%u\n", pkt_len, GNUNET_i2s (sender), - inet_ntop (state->ri.remote_address.af, - &state->ri.remote_address.address, + inet_ntop (state->specifics.tcp_udp.ri.remote_address.af, + &state->specifics.tcp_udp.ri.remote_address.address, buf, sizeof (buf)), - (unsigned int) state->ri.remote_address.port); + (unsigned int) state->specifics.tcp_udp.ri.remote_address.port); } - send_tcp_packet_via_tun (&state->ri.remote_address, - &state->ri.local_address, + send_tcp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, + &state->specifics.tcp_udp.ri.local_address, &data->tcp_header, &data[1], pkt_len); return GNUNET_YES; @@ -1800,7 +2116,7 @@ send_icmp_packet_via_tun (const struct SocketAddress *destination_address, return; } { - char buf[len]; + char buf[len] GNUNET_ALIGN; struct GNUNET_MessageHeader *hdr; struct GNUNET_TUN_Layer2PacketHeader *tun; @@ -1830,7 +2146,7 @@ send_icmp_packet_via_tun (const struct SocketAddress *destination_address, tun->proto = htons (ETH_P_IPV6); GNUNET_TUN_initialize_ipv6_header (ipv6, - IPPROTO_ICMP, + IPPROTO_ICMPV6, sizeof (struct GNUNET_TUN_IcmpHeader) + payload_length, &source_address->address.ipv6, &destination_address->address.ipv6); @@ -1848,14 +2164,67 @@ send_icmp_packet_via_tun (const struct SocketAddress *destination_address, GNUNET_TUN_calculate_icmp_checksum (icmp, payload, payload_length); - (void) GNUNET_HELPER_send (helper_handle, - (const struct GNUNET_MessageHeader*) buf, - GNUNET_YES, - NULL, NULL); + if (NULL != helper_handle) + (void) GNUNET_HELPER_send (helper_handle, + (const struct GNUNET_MessageHeader*) buf, + GNUNET_YES, + NULL, NULL); } } +/** + * Synthesize a plausible ICMP payload for an ICMPv4 error + * response on the given tunnel. + * + * @param state tunnel information + * @param ipp IPv6 header to fill in (ICMP payload) + * @param udp "UDP" header to fill in (ICMP payload); might actually + * also be the first 8 bytes of the TCP header + */ +static void +make_up_icmpv4_payload (struct TunnelState *state, + struct GNUNET_TUN_IPv4Header *ipp, + struct GNUNET_TUN_UdpHeader *udp) +{ + GNUNET_TUN_initialize_ipv4_header (ipp, + state->specifics.tcp_udp.ri.remote_address.proto, + sizeof (struct GNUNET_TUN_TcpHeader), + &state->specifics.tcp_udp.ri.remote_address.address.ipv4, + &state->specifics.tcp_udp.ri.local_address.address.ipv4); + udp->source_port = htons (state->specifics.tcp_udp.ri.remote_address.port); + udp->destination_port = htons (state->specifics.tcp_udp.ri.local_address.port); + udp->len = htons (0); + udp->crc = htons (0); +} + + +/** + * Synthesize a plausible ICMP payload for an ICMPv6 error + * response on the given tunnel. + * + * @param state tunnel information + * @param ipp IPv6 header to fill in (ICMP payload) + * @param udp "UDP" header to fill in (ICMP payload); might actually + * also be the first 8 bytes of the TCP header + */ +static void +make_up_icmpv6_payload (struct TunnelState *state, + struct GNUNET_TUN_IPv6Header *ipp, + struct GNUNET_TUN_UdpHeader *udp) +{ + GNUNET_TUN_initialize_ipv6_header (ipp, + state->specifics.tcp_udp.ri.remote_address.proto, + sizeof (struct GNUNET_TUN_TcpHeader), + &state->specifics.tcp_udp.ri.remote_address.address.ipv6, + &state->specifics.tcp_udp.ri.local_address.address.ipv6); + udp->source_port = htons (state->specifics.tcp_udp.ri.remote_address.port); + udp->destination_port = htons (state->specifics.tcp_udp.ri.local_address.port); + udp->len = htons (0); + udp->crc = htons (0); +} + + /** * Process a request to forward ICMP data to the Internet via this peer. * @@ -1881,8 +2250,19 @@ receive_icmp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, const struct in_addr *v4; const struct in6_addr *v6; const void *payload; + char buf[sizeof (struct GNUNET_TUN_IPv6Header) + 8] GNUNET_ALIGN; int af; + if (GNUNET_YES == state->is_dns) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_SYSERR == state->is_dns) + { + /* tunnel is UDP/TCP from now on */ + state->is_dns = GNUNET_NO; + } GNUNET_STATISTICS_update (stats, gettext_noop ("# Bytes received from MESH"), pkt_len, GNUNET_NO); @@ -1898,7 +2278,14 @@ receive_icmp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, pkt_len -= sizeof (struct GNUNET_EXIT_IcmpInternetMessage); af = (int) ntohl (msg->af); - state->ri.remote_address.af = af; + if ( (NULL != state->specifics.tcp_udp.heap_node) && + (af != state->specifics.tcp_udp.ri.remote_address.af) ) + { + /* other peer switched AF on this tunnel; not allowed */ + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + switch (af) { case AF_INET: @@ -1915,7 +2302,49 @@ receive_icmp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, v4 = (const struct in_addr*) &msg[1]; payload = &v4[1]; pkt_len -= sizeof (struct in_addr); - state->ri.remote_address.address.ipv4 = *v4; + state->specifics.tcp_udp.ri.remote_address.address.ipv4 = *v4; + if (NULL == state->specifics.tcp_udp.heap_node) + { + state->specifics.tcp_udp.ri.remote_address.af = af; + state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_ICMP; + setup_state_record (state); + } + /* check that ICMP type is something we want to support + and possibly make up payload! */ + switch (msg->icmp_header.type) + { + case GNUNET_TUN_ICMPTYPE_ECHO_REPLY: + case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST: + break; + case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE: + case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH: + case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED: + if (0 != pkt_len) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + /* make up payload */ + { + struct GNUNET_TUN_IPv4Header *ipp = (struct GNUNET_TUN_IPv4Header *) buf; + struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1]; + + GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader)); + pkt_len = sizeof (struct GNUNET_TUN_IPv4Header) + 8; + make_up_icmpv4_payload (state, + ipp, + udp); + payload = ipp; + } + break; + default: + GNUNET_break_op (0); + GNUNET_STATISTICS_update (stats, + gettext_noop ("# ICMPv4 packets dropped (type not allowed)"), + 1, GNUNET_NO); + return GNUNET_SYSERR; + } + /* end AF_INET */ break; case AF_INET6: if (pkt_len < sizeof (struct in6_addr)) @@ -1931,9 +2360,53 @@ receive_icmp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, v6 = (const struct in6_addr*) &msg[1]; payload = &v6[1]; pkt_len -= sizeof (struct in6_addr); - state->ri.remote_address.address.ipv6 = *v6; - break; + state->specifics.tcp_udp.ri.remote_address.address.ipv6 = *v6; + if (NULL == state->specifics.tcp_udp.heap_node) + { + state->specifics.tcp_udp.ri.remote_address.af = af; + state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_ICMPV6; + setup_state_record (state); + } + /* check that ICMP type is something we want to support + and possibly make up payload! */ + switch (msg->icmp_header.type) + { + case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY: + case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST: + break; + case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE: + case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG: + case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED: + case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM: + if (0 != pkt_len) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + /* make up payload */ + { + struct GNUNET_TUN_IPv6Header *ipp = (struct GNUNET_TUN_IPv6Header *) buf; + struct GNUNET_TUN_UdpHeader *udp = (struct GNUNET_TUN_UdpHeader *) &ipp[1]; + + GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader)); + pkt_len = sizeof (struct GNUNET_TUN_IPv6Header) + 8; + make_up_icmpv6_payload (state, + ipp, + udp); + payload = ipp; + } + break; + default: + GNUNET_break_op (0); + GNUNET_STATISTICS_update (stats, + gettext_noop ("# ICMPv6 packets dropped (type not allowed)"), + 1, GNUNET_NO); + return GNUNET_SYSERR; + } + /* end AF_INET6 */ + break; default: + /* bad AF */ GNUNET_break_op (0); return GNUNET_SYSERR; } @@ -1944,26 +2417,67 @@ receive_icmp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, "Received ICMP data from %s for forwarding to %s\n", GNUNET_i2s (sender), inet_ntop (af, - &state->ri.remote_address.address, + &state->specifics.tcp_udp.ri.remote_address.address, buf, sizeof (buf))); } - - /* FIXME: check that ICMP type is something we want to support */ - - state->ri.remote_address.proto = IPPROTO_ICMP; - state->ri.remote_address.port = 0; - state->ri.local_address.port = 0; - if (NULL == state->heap_node) - setup_state_record (state); - - send_icmp_packet_via_tun (&state->ri.remote_address, - &state->ri.local_address, + send_icmp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, + &state->specifics.tcp_udp.ri.local_address, &msg->icmp_header, payload, pkt_len); return GNUNET_YES; } +/** + * Setup ICMP payload for ICMP error messages. Called + * for both IPv4 and IPv6 addresses. + * + * @param state context for creating the IP Packet + * @param buf where to create the payload, has at least + * sizeof (struct GNUNET_TUN_IPv6Header) + 8 bytes + * @return number of bytes of payload we created in buf + */ +static uint16_t +make_up_icmp_service_payload (struct TunnelState *state, + char *buf) +{ + switch (state->specifics.tcp_udp.serv->address.af) + { + case AF_INET: + { + struct GNUNET_TUN_IPv4Header *ipv4; + struct GNUNET_TUN_UdpHeader *udp; + + ipv4 = (struct GNUNET_TUN_IPv4Header *)buf; + udp = (struct GNUNET_TUN_UdpHeader *) &ipv4[1]; + make_up_icmpv4_payload (state, + ipv4, + udp); + GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader)); + return sizeof (struct GNUNET_TUN_IPv4Header) + 8; + } + break; + case AF_INET6: + { + struct GNUNET_TUN_IPv6Header *ipv6; + struct GNUNET_TUN_UdpHeader *udp; + + ipv6 = (struct GNUNET_TUN_IPv6Header *)buf; + udp = (struct GNUNET_TUN_UdpHeader *) &ipv6[1]; + make_up_icmpv6_payload (state, + ipv6, + udp); + GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader)); + return sizeof (struct GNUNET_TUN_IPv6Header) + 8; + } + break; + default: + GNUNET_break (0); + } + return 0; +} + + /** * Process a request via mesh to send ICMP data to a service * offered by this system. @@ -1987,7 +2501,20 @@ receive_icmp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel struct TunnelState *state = *tunnel_ctx; const struct GNUNET_EXIT_IcmpServiceMessage *msg; uint16_t pkt_len = ntohs (message->size); + struct GNUNET_TUN_IcmpHeader icmp; + char buf[sizeof (struct GNUNET_TUN_IPv6Header) + 8] GNUNET_ALIGN; + const void *payload; + if (GNUNET_YES == state->is_dns) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_SYSERR == state->is_dns) + { + /* tunnel is UDP/TCP from now on */ + state->is_dns = GNUNET_NO; + } GNUNET_STATISTICS_update (stats, gettext_noop ("# Bytes received from MESH"), pkt_len, GNUNET_NO); @@ -2006,29 +2533,147 @@ receive_icmp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel "Received data from %s for forwarding to ICMP service %s\n", GNUNET_i2s (sender), GNUNET_h2s (&msg->service_descriptor)); - if (NULL == state->serv) + if (NULL == state->specifics.tcp_udp.serv) { /* first packet to service must not be ICMP (cannot determine service!) */ GNUNET_break_op (0); return GNUNET_SYSERR; } - if (state->serv->address.af != ntohl (msg->af)) + icmp = msg->icmp_header; + payload = &msg[1]; + state->specifics.tcp_udp.ri.remote_address = state->specifics.tcp_udp.serv->address; + setup_state_record (state); + + /* check that ICMP type is something we want to support, + perform ICMP PT if needed ans possibly make up payload */ + switch (msg->af) { - GNUNET_STATISTICS_update (stats, - gettext_noop ("# ICMP service requests discarded (incompatible af)"), - 1, GNUNET_NO); + case AF_INET: + switch (msg->icmp_header.type) + { + case GNUNET_TUN_ICMPTYPE_ECHO_REPLY: + if (state->specifics.tcp_udp.serv->address.af == AF_INET6) + icmp.type = GNUNET_TUN_ICMPTYPE6_ECHO_REPLY; + break; + case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST: + if (state->specifics.tcp_udp.serv->address.af == AF_INET6) + icmp.type = GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST; + break; + case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE: + if (state->specifics.tcp_udp.serv->address.af == AF_INET6) + icmp.type = GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE; + if (0 != pkt_len) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + payload = buf; + pkt_len = make_up_icmp_service_payload (state, buf); + break; + case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED: + if (state->specifics.tcp_udp.serv->address.af == AF_INET6) + icmp.type = GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED; + if (0 != pkt_len) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + payload = buf; + pkt_len = make_up_icmp_service_payload (state, buf); + break; + case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH: + if (state->specifics.tcp_udp.serv->address.af == AF_INET6) + { + GNUNET_STATISTICS_update (stats, + gettext_noop ("# ICMPv4 packets dropped (impossible PT to v6)"), + 1, GNUNET_NO); + return GNUNET_OK; + } + if (0 != pkt_len) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + payload = buf; + pkt_len = make_up_icmp_service_payload (state, buf); + break; + default: + GNUNET_break_op (0); + GNUNET_STATISTICS_update (stats, + gettext_noop ("# ICMPv4 packets dropped (type not allowed)"), + 1, GNUNET_NO); + return GNUNET_SYSERR; + } + /* end of AF_INET */ + break; + case AF_INET6: + switch (msg->icmp_header.type) + { + case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY: + if (state->specifics.tcp_udp.serv->address.af == AF_INET) + icmp.type = GNUNET_TUN_ICMPTYPE_ECHO_REPLY; + break; + case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST: + if (state->specifics.tcp_udp.serv->address.af == AF_INET) + icmp.type = GNUNET_TUN_ICMPTYPE_ECHO_REQUEST; + break; + case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE: + if (state->specifics.tcp_udp.serv->address.af == AF_INET) + icmp.type = GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE; + if (0 != pkt_len) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + payload = buf; + pkt_len = make_up_icmp_service_payload (state, buf); + break; + case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED: + if (state->specifics.tcp_udp.serv->address.af == AF_INET) + icmp.type = GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED; + if (0 != pkt_len) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + payload = buf; + pkt_len = make_up_icmp_service_payload (state, buf); + break; + case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG: + case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM: + if (state->specifics.tcp_udp.serv->address.af == AF_INET) + { + GNUNET_STATISTICS_update (stats, + gettext_noop ("# ICMPv6 packets dropped (impossible PT to v4)"), + 1, GNUNET_NO); + return GNUNET_OK; + } + if (0 != pkt_len) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + payload = buf; + pkt_len = make_up_icmp_service_payload (state, buf); + break; + default: + GNUNET_break_op (0); + GNUNET_STATISTICS_update (stats, + gettext_noop ("# ICMPv6 packets dropped (type not allowed)"), + 1, GNUNET_NO); + return GNUNET_SYSERR; + } + /* end of AF_INET6 */ + break; + default: + GNUNET_break_op (0); return GNUNET_SYSERR; } - /* FIXME: check that ICMP type is something we want to support */ - - state->ri.remote_address = state->serv->address; - setup_state_record (state); - - send_icmp_packet_via_tun (&state->ri.remote_address, - &state->ri.local_address, - &msg->icmp_header, - &msg[1], pkt_len); + send_icmp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, + &state->specifics.tcp_udp.ri.local_address, + &icmp, + payload, pkt_len); return GNUNET_YES; } @@ -2075,7 +2720,7 @@ send_udp_packet_via_tun (const struct SocketAddress *destination_address, return; } { - char buf[len]; + char buf[len] GNUNET_ALIGN; struct GNUNET_MessageHeader *hdr; struct GNUNET_TUN_Layer2PacketHeader *tun; @@ -2116,10 +2761,11 @@ send_udp_packet_via_tun (const struct SocketAddress *destination_address, GNUNET_assert (0); break; } - (void) GNUNET_HELPER_send (helper_handle, - (const struct GNUNET_MessageHeader*) buf, - GNUNET_YES, - NULL, NULL); + if (NULL != helper_handle) + (void) GNUNET_HELPER_send (helper_handle, + (const struct GNUNET_MessageHeader*) buf, + GNUNET_YES, + NULL, NULL); } } @@ -2151,6 +2797,16 @@ receive_udp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, const void *payload; int af; + if (GNUNET_YES == state->is_dns) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_SYSERR == state->is_dns) + { + /* tunnel is UDP/TCP from now on */ + state->is_dns = GNUNET_NO; + } GNUNET_STATISTICS_update (stats, gettext_noop ("# Bytes received from MESH"), pkt_len, GNUNET_NO); @@ -2165,7 +2821,7 @@ receive_udp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, msg = (const struct GNUNET_EXIT_UdpInternetMessage*) message; pkt_len -= sizeof (struct GNUNET_EXIT_UdpInternetMessage); af = (int) ntohl (msg->af); - state->ri.remote_address.af = af; + state->specifics.tcp_udp.ri.remote_address.af = af; switch (af) { case AF_INET: @@ -2182,7 +2838,7 @@ receive_udp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, v4 = (const struct in_addr*) &msg[1]; payload = &v4[1]; pkt_len -= sizeof (struct in_addr); - state->ri.remote_address.address.ipv4 = *v4; + state->specifics.tcp_udp.ri.remote_address.address.ipv4 = *v4; break; case AF_INET6: if (pkt_len < sizeof (struct in6_addr)) @@ -2198,7 +2854,7 @@ receive_udp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, v6 = (const struct in6_addr*) &msg[1]; payload = &v6[1]; pkt_len -= sizeof (struct in6_addr); - state->ri.remote_address.address.ipv6 = *v6; + state->specifics.tcp_udp.ri.remote_address.address.ipv6 = *v6; break; default: GNUNET_break_op (0); @@ -2210,18 +2866,18 @@ receive_udp_remote (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, "Received data from %s for forwarding to UDP %s:%u\n", GNUNET_i2s (sender), inet_ntop (af, - &state->ri.remote_address.address, + &state->specifics.tcp_udp.ri.remote_address.address, buf, sizeof (buf)), (unsigned int) ntohs (msg->destination_port)); } - state->ri.remote_address.proto = IPPROTO_UDP; - state->ri.remote_address.port = msg->destination_port; - if (NULL == state->heap_node) + state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_UDP; + state->specifics.tcp_udp.ri.remote_address.port = msg->destination_port; + if (NULL == state->specifics.tcp_udp.heap_node) setup_state_record (state); if (0 != ntohs (msg->source_port)) - state->ri.local_address.port = msg->source_port; - send_udp_packet_via_tun (&state->ri.remote_address, - &state->ri.local_address, + state->specifics.tcp_udp.ri.local_address.port = msg->source_port; + send_udp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, + &state->specifics.tcp_udp.ri.local_address, payload, pkt_len); return GNUNET_YES; } @@ -2251,6 +2907,16 @@ receive_udp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, const struct GNUNET_EXIT_UdpServiceMessage *msg; uint16_t pkt_len = ntohs (message->size); + if (GNUNET_YES == state->is_dns) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + if (GNUNET_SYSERR == state->is_dns) + { + /* tunnel is UDP/TCP from now on */ + state->is_dns = GNUNET_NO; + } GNUNET_STATISTICS_update (stats, gettext_noop ("# Bytes received from MESH"), pkt_len, GNUNET_NO); @@ -2265,13 +2931,13 @@ receive_udp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, } msg = (const struct GNUNET_EXIT_UdpServiceMessage*) message; pkt_len -= sizeof (struct GNUNET_EXIT_UdpServiceMessage); - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Received data from %s for forwarding to UDP service %s on port %u\n", - GNUNET_i2s (sender), - GNUNET_h2s (&msg->service_descriptor), - (unsigned int) ntohs (msg->destination_port)); - if (NULL == (state->serv = find_service (udp_services, &msg->service_descriptor, - ntohs (msg->destination_port)))) + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Received data from %s for forwarding to UDP service %s on port %u\n", + GNUNET_i2s (sender), + GNUNET_h2s (&msg->service_descriptor), + (unsigned int) ntohs (msg->destination_port)); + if (NULL == (state->specifics.tcp_udp.serv = find_service (udp_services, &msg->service_descriptor, + ntohs (msg->destination_port)))) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("No service found for %s on port %d!\n"), @@ -2282,12 +2948,12 @@ receive_udp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, 1, GNUNET_NO); return GNUNET_SYSERR; } - state->ri.remote_address = state->serv->address; + state->specifics.tcp_udp.ri.remote_address = state->specifics.tcp_udp.serv->address; setup_state_record (state); if (0 != ntohs (msg->source_port)) - state->ri.local_address.port = msg->source_port; - send_udp_packet_via_tun (&state->ri.remote_address, - &state->ri.local_address, + state->specifics.tcp_udp.ri.local_address.port = msg->source_port; + send_udp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, + &state->specifics.tcp_udp.ri.local_address, &msg[1], pkt_len); return GNUNET_YES; } @@ -2305,10 +2971,11 @@ receive_udp_service (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, static void * new_tunnel (void *cls GNUNET_UNUSED, struct GNUNET_MESH_Tunnel *tunnel, const struct GNUNET_PeerIdentity *initiator GNUNET_UNUSED, - const struct GNUNET_ATS_Information *ats GNUNET_UNUSED) + const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED) { struct TunnelState *s = GNUNET_malloc (sizeof (struct TunnelState)); + s->is_dns = GNUNET_SYSERR; GNUNET_STATISTICS_update (stats, gettext_noop ("# Inbound MESH tunnels created"), 1, GNUNET_NO); @@ -2336,23 +3003,37 @@ clean_tunnel (void *cls GNUNET_UNUSED, const struct GNUNET_MESH_Tunnel *tunnel, struct TunnelState *s = tunnel_ctx; struct TunnelMessageQueue *tnq; - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Tunnel destroyed\n"); - while (NULL != (tnq = s->head)) + LOG (GNUNET_ERROR_TYPE_DEBUG, + "Tunnel destroyed\n"); + if (GNUNET_SYSERR == s->is_dns) { - GNUNET_CONTAINER_DLL_remove (s->head, - s->tail, - tnq); - GNUNET_free (tnq); + GNUNET_free (s); + return; } - if (s->heap_node != NULL) + if (GNUNET_YES == s->is_dns) { - GNUNET_assert (GNUNET_YES == - GNUNET_CONTAINER_multihashmap_remove (connections_map, - &s->state_key, - s)); - GNUNET_CONTAINER_heap_remove_node (s->heap_node); - s->heap_node = NULL; + if (tunnels[s->specifics.dns.my_id] == s) + tunnels[s->specifics.dns.my_id] = NULL; + GNUNET_free_non_null (s->specifics.dns.reply); + } + else + { + while (NULL != (tnq = s->specifics.tcp_udp.head)) + { + GNUNET_CONTAINER_DLL_remove (s->specifics.tcp_udp.head, + s->specifics.tcp_udp.tail, + tnq); + GNUNET_free (tnq); + } + if (NULL != s->specifics.tcp_udp.heap_node) + { + GNUNET_assert (GNUNET_YES == + GNUNET_CONTAINER_multihashmap_remove (connections_map, + &s->specifics.tcp_udp.state_key, + s)); + GNUNET_CONTAINER_heap_remove_node (s->specifics.tcp_udp.heap_node); + s->specifics.tcp_udp.heap_node = NULL; + } } if (NULL != s->th) { @@ -2372,7 +3053,7 @@ clean_tunnel (void *cls GNUNET_UNUSED, const struct GNUNET_MESH_Tunnel *tunnel, */ static int free_iterate (void *cls GNUNET_UNUSED, - const GNUNET_HashCode * hash GNUNET_UNUSED, void *value) + const struct GNUNET_HashCode * hash GNUNET_UNUSED, void *value) { GNUNET_free (value); return GNUNET_YES; @@ -2390,6 +3071,7 @@ cleanup (void *cls GNUNET_UNUSED, GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Exit service is shutting down now\n"); + if (helper_handle != NULL) { GNUNET_HELPER_stop (helper_handle); @@ -2423,12 +3105,17 @@ cleanup (void *cls GNUNET_UNUSED, GNUNET_CONTAINER_multihashmap_destroy (udp_services); udp_services = NULL; } + if (NULL != dnsstub) + { + GNUNET_DNSSTUB_stop (dnsstub); + dnsstub = NULL; + } if (stats != NULL) { - GNUNET_STATISTICS_destroy (stats, GNUNET_YES); + GNUNET_STATISTICS_destroy (stats, GNUNET_NO); stats = NULL; } - for (i=0;i<5;i++) + for (i=0;i<8;i++) GNUNET_free_non_null (exit_argv[i]); } @@ -2493,18 +3180,19 @@ add_services (int proto, } serv = GNUNET_malloc (sizeof (struct LocalService)); + serv->address.proto = proto; serv->my_port = (uint16_t) local_port; serv->address.port = remote_port; if (0 == strcmp ("localhost4", hostname)) { - const char *ip4addr = exit_argv[4]; + const char *ip4addr = exit_argv[5]; serv->address.af = AF_INET; - GNUNET_assert (1 != inet_pton (AF_INET, ip4addr, &serv->address.address.ipv4)); + GNUNET_assert (1 == inet_pton (AF_INET, ip4addr, &serv->address.address.ipv4)); } else if (0 == strcmp ("localhost6", hostname)) { - const char *ip6addr = exit_argv[2]; + const char *ip6addr = exit_argv[3]; serv->address.af = AF_INET6; GNUNET_assert (1 == inet_pton (AF_INET6, ip6addr, &serv->address.address.ipv6)); @@ -2623,10 +3311,12 @@ run (void *cls, char *const *args GNUNET_UNUSED, {&receive_tcp_service, GNUNET_MESSAGE_TYPE_VPN_TCP_TO_SERVICE_START, 0}, {&receive_tcp_remote, GNUNET_MESSAGE_TYPE_VPN_TCP_TO_INTERNET_START, 0}, {&receive_tcp_data, GNUNET_MESSAGE_TYPE_VPN_TCP_DATA_TO_EXIT, 0}, + {&receive_dns_request, GNUNET_MESSAGE_TYPE_VPN_DNS_TO_INTERNET, 0}, {NULL, 0, 0} }; static GNUNET_MESH_ApplicationType apptypes[] = { + GNUNET_APPLICATION_TYPE_END, GNUNET_APPLICATION_TYPE_END, GNUNET_APPLICATION_TYPE_END, GNUNET_APPLICATION_TYPE_END @@ -2638,13 +3328,51 @@ run (void *cls, char *const *args GNUNET_UNUSED, char *ipv6prefix_s; char *ipv4addr; char *ipv4mask; + char *binary; + char *regex; + char *prefixed_regex; + struct in_addr dns_exit4; + struct in6_addr dns_exit6; + char *dns_exit; cfg = cfg_; - stats = GNUNET_STATISTICS_create ("exit", cfg); ipv4_exit = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "EXIT_IPV4"); ipv6_exit = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "EXIT_IPV6"); ipv4_enabled = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "ENABLE_IPV4"); ipv6_enabled = GNUNET_CONFIGURATION_get_value_yesno (cfg, "exit", "ENABLE_IPV6"); + if ( (ipv4_exit) || (ipv6_exit) ) + { + binary = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-exit"); + if (GNUNET_YES != + GNUNET_OS_check_helper_binary (binary)) + { + GNUNET_free (binary); + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _("`%s' must be installed SUID, refusing to run\n"), + "gnunet-helper-exit"); + global_ret = 1; + return; + } + GNUNET_free (binary); + } + stats = GNUNET_STATISTICS_create ("exit", cfg); + + if ( (ipv4_exit || ipv4_enabled) && + GNUNET_OK != GNUNET_NETWORK_test_pf (PF_INET)) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _("This system does not support IPv4, will disable IPv4 functions despite them being enabled in the configuration\n")); + ipv4_exit = GNUNET_NO; + ipv4_enabled = GNUNET_NO; + } + if ( (ipv6_exit || ipv6_enabled) && + GNUNET_OK != GNUNET_NETWORK_test_pf (PF_INET6)) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _("This system does not support IPv6, will disable IPv6 functions despite them being enabled in the configuration\n")); + ipv6_exit = GNUNET_NO; + ipv6_enabled = GNUNET_NO; + } if (ipv4_exit && (! ipv4_enabled)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, @@ -2664,6 +3392,26 @@ run (void *cls, char *const *args GNUNET_UNUSED, GNUNET_SCHEDULER_shutdown (); return; } + + dns_exit = NULL; + if ( (GNUNET_YES == + GNUNET_CONFIGURATION_get_value_yesno (cfg_, "exit", "ENABLE_DNS")) && + ( (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_string (cfg, "exit", + "DNS_RESOLVER", + &dns_exit)) || + ( (1 != inet_pton (AF_INET, dns_exit, &dns_exit4)) && + (1 != inet_pton (AF_INET6, dns_exit, &dns_exit6)) ) ) ) + { + GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "dns", "DNS_RESOLVER", + _("need a valid IPv4 or IPv6 address\n")); + GNUNET_free_non_null (dns_exit); + dns_exit = NULL; + } + if (NULL != dns_exit) + dnsstub = GNUNET_DNSSTUB_start (dns_exit); + + app_idx = 0; if (GNUNET_YES == ipv4_exit) { @@ -2675,6 +3423,11 @@ run (void *cls, char *const *args GNUNET_UNUSED, apptypes[app_idx] = GNUNET_APPLICATION_TYPE_IPV6_GATEWAY; app_idx++; } + if (NULL != dns_exit) + { + apptypes[app_idx] = GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER; + app_idx++; + } GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls); @@ -2708,6 +3461,8 @@ run (void *cls, char *const *args GNUNET_UNUSED, { exit_argv[2] = GNUNET_strdup ("%"); } + + if (GNUNET_YES == ipv6_enabled) { if ( (GNUNET_SYSERR == @@ -2780,14 +3535,14 @@ run (void *cls, char *const *args GNUNET_UNUSED, } exit_argv[7] = NULL; - udp_services = GNUNET_CONTAINER_multihashmap_create (65536); - tcp_services = GNUNET_CONTAINER_multihashmap_create (65536); + udp_services = GNUNET_CONTAINER_multihashmap_create (65536, GNUNET_NO); + tcp_services = GNUNET_CONTAINER_multihashmap_create (65536, GNUNET_NO); GNUNET_CONFIGURATION_iterate_sections (cfg, &read_service_conf, NULL); - connections_map = GNUNET_CONTAINER_multihashmap_create (65536); + connections_map = GNUNET_CONTAINER_multihashmap_create (65536, GNUNET_NO); connections_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN); mesh_handle - = GNUNET_MESH_connect (cfg, 42 /* queue size */, NULL, + = GNUNET_MESH_connect (cfg, NULL, &new_tunnel, &clean_tunnel, handlers, apptypes); @@ -2796,9 +3551,49 @@ run (void *cls, char *const *args GNUNET_UNUSED, GNUNET_SCHEDULER_shutdown (); return; } - helper_handle = GNUNET_HELPER_start ("gnunet-helper-exit", - exit_argv, - &message_token, NULL); + + /* Mesh handle acquired, now announce regular expressions matching our exit */ + if ( (GNUNET_YES == ipv4_enabled) && (GNUNET_YES == ipv4_exit) ) + { + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_string (cfg, + "exit", + "EXIT_RANGE_IPV4_REGEX", + ®ex)) + regex = GNUNET_strdup ("(0|1)*"); + (void) GNUNET_asprintf (&prefixed_regex, "%s%s%s", + GNUNET_APPLICATION_TYPE_EXIT_REGEX_PREFIX, + "4", regex); + GNUNET_MESH_announce_regex (mesh_handle, + prefixed_regex, + REGEX_MAX_PATH_LEN_IPV4); + GNUNET_free (regex); + GNUNET_free (prefixed_regex); + } + + if (GNUNET_YES == ipv6_enabled && GNUNET_YES == ipv6_exit) + { + if (GNUNET_OK != + GNUNET_CONFIGURATION_get_value_string (cfg, + "exit", + "EXIT_RANGE_IPV6_REGEX", + ®ex)) + regex = GNUNET_strdup ("(0|1)*"); + (void) GNUNET_asprintf (&prefixed_regex, "%s%s%s", + GNUNET_APPLICATION_TYPE_EXIT_REGEX_PREFIX, + "6", regex); + GNUNET_MESH_announce_regex (mesh_handle, + prefixed_regex, + REGEX_MAX_PATH_LEN_IPV6); + GNUNET_free (regex); + GNUNET_free (prefixed_regex); + } + if ((ipv4_exit) || (ipv6_exit)) + helper_handle = GNUNET_HELPER_start (GNUNET_NO, + "gnunet-helper-exit", + exit_argv, + &message_token, + NULL, NULL); } @@ -2816,11 +3611,14 @@ main (int argc, char *const *argv) GNUNET_GETOPT_OPTION_END }; + if (GNUNET_OK != GNUNET_STRINGS_get_utf8_args (argc, argv, &argc, &argv)) + return 2; + return (GNUNET_OK == GNUNET_PROGRAM_run (argc, argv, "gnunet-daemon-exit", gettext_noop ("Daemon to run to provide an IP exit node for the VPN"), - options, &run, NULL)) ? 0 : 1; + options, &run, NULL)) ? global_ret : 1; }