* @author Christian Grothoff
*
* TODO:
- * - implement service message handlers
- * - define mesh message formats between VPN and EXIT!
* - build mesh messages
* - parse mesh replies
* - build IP messages from mesh replies
#include "gnunet_constants.h"
#include "tcpip_tun.h"
#include "vpn.h"
-
+#include "exit.h"
/**
* Information we track for each IP address to determine which tunnel
*/
static char *vpn_argv[7];
+/**
+ * Length of the prefix of the VPN's IPv6 network.
+ */
+static unsigned long long ipv6prefix;
+
/**
* Notification context for sending replies to clients.
*/
}
+/**
+ * Notify the client about the result of its request.
+ *
+ * @param client client to notify
+ * @param request_id original request ID to include in response
+ * @param result_af resulting address family
+ * @param addr resulting IP address
+ */
+static void
+send_client_reply (struct GNUNET_SERVER_Client *client,
+ uint64_t request_id,
+ int result_af,
+ const void *addr)
+{
+ char buf[sizeof (struct RedirectToIpResponseMessage) + sizeof (struct in6_addr)];
+ struct RedirectToIpResponseMessage *res;
+ size_t rlen;
+
+ switch (result_af)
+ {
+ case AF_INET:
+ rlen = sizeof (struct in_addr);
+ break;
+ case AF_INET6:
+ rlen = sizeof (struct in6_addr);
+ break;
+ case AF_UNSPEC:
+ rlen = 0;
+ break;
+ default:
+ GNUNET_assert (0);
+ return;
+ }
+ res = (struct RedirectToIpResponseMessage *) buf;
+ res->header.size = htons (sizeof (struct RedirectToIpResponseMessage) + rlen);
+ res->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_CLIENT_USE_IP);
+ res->result_af = htonl (result_af);
+ res->request_id = request_id;
+ memcpy (&res[1], addr, rlen);
+ GNUNET_SERVER_notification_context_add (nc, client);
+ GNUNET_SERVER_notification_context_unicast (nc,
+ client,
+ &res->header,
+ GNUNET_NO);
+}
+
+
+/**
+ * Method called whenever a peer has disconnected from the tunnel.
+ *
+ * @param cls closure
+ * @param peer peer identity the tunnel stopped working with
+ */
+static void
+tunnel_peer_disconnect_handler (void *cls,
+ const struct
+ GNUNET_PeerIdentity * peer)
+{
+ /* FIXME: should we do anything here?
+ - stop transmitting to the tunnel (start queueing?)
+ - possibly destroy the tunnel entirely (unless service tunnel?)
+ */
+}
+
+
+/**
+ * Method called whenever a peer has connected to the tunnel. Notifies
+ * the waiting client that the tunnel is now up.
+ *
+ * @param cls closure
+ * @param peer peer identity the tunnel was created to, NULL on timeout
+ * @param atsi performance data for the connection
+ */
+static void
+tunnel_peer_connect_handler (void *cls,
+ const struct GNUNET_PeerIdentity
+ * peer,
+ const struct
+ GNUNET_ATS_Information * atsi)
+{
+ struct TunnelState *ts = cls;
+
+ if (NULL == ts->client)
+ return; /* nothing to do */
+ send_client_reply (ts->client,
+ ts->request_id,
+ ts->af,
+ &ts->destination_ip);
+ GNUNET_SERVER_client_drop (ts->client);
+ ts->client = NULL;
+}
+
+
/**
* Send a message from the message queue via mesh.
*
*/
static void
send_to_tunnel (struct TunnelMessageQueueEntry *tnq,
- struct TunnelState *ts)
+ struct TunnelState *ts)
{
GNUNET_CONTAINER_DLL_insert_tail (ts->head,
ts->tail,
GNUNET_HashCode key;
struct TunnelState *ts;
struct TunnelMessageQueueEntry *tnq;
-
+ size_t alen;
+ size_t mlen;
+ GNUNET_MESH_ApplicationType app_type;
+ int is_new;
+ const struct udp_packet *udp;
+ const struct tcp_packet *tcp;
+
switch (protocol)
{
case IPPROTO_UDP:
{
- const struct udp_packet *udp;
-
if (payload_length < sizeof (struct udp_packet))
{
/* blame kernel? */
break;
case IPPROTO_TCP:
{
- const struct tcp_packet *tcp;
-
if (payload_length < sizeof (struct tcp_packet))
{
/* blame kernel? */
return;
}
+ if (! destination->is_service)
+ {
+ switch (destination->details.exit_destination.af)
+ {
+ case AF_INET:
+ alen = sizeof (struct in_addr);
+ app_type = GNUNET_APPLICATION_TYPE_IPV4_GATEWAY;
+ break;
+ case AF_INET6:
+ alen = sizeof (struct in6_addr);
+ app_type = GNUNET_APPLICATION_TYPE_IPV6_GATEWAY;
+ break;
+ default:
+ alen = 0;
+ GNUNET_assert (0);
+ }
+ }
+ else
+ {
+ /* make compiler happy */
+ alen = 0;
+ app_type = 0;
+ }
+
+ // FIXME: something is horrifically wrong here about
+ // how we lookup 'ts', match it and how we decide about
+ // creating new tunnels!
/* find tunnel */
+ is_new = GNUNET_NO;
ts = GNUNET_CONTAINER_multihashmap_get (tunnel_map,
&key);
if (NULL == ts)
{
/* create new tunnel */
- // FIXME: create tunnel!
-#if 0
- *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);
- me->tunnel = *cls;
-#endif
+ is_new = GNUNET_YES;
+ ts = GNUNET_malloc (sizeof (struct TunnelState));
+ ts->destination.tunnel = GNUNET_MESH_tunnel_create (mesh_handle,
+ ts,
+ &tunnel_peer_connect_handler,
+ &tunnel_peer_disconnect_handler,
+ ts);
+ if (destination->is_service)
+ GNUNET_MESH_peer_request_connect_add (ts->destination.tunnel,
+ &destination->details.service_destination.target);
+ else
+ GNUNET_MESH_peer_request_connect_by_type (ts->destination.tunnel,
+ app_type);
}
/* send via tunnel */
case IPPROTO_UDP:
if (destination->is_service)
{
- tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + 42);
- // FIXME: build message!
+ struct GNUNET_EXIT_UdpServiceMessage *usm;
+
+ mlen = sizeof (struct GNUNET_EXIT_UdpServiceMessage) +
+ payload_length - sizeof (struct udp_packet);
+ if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+ {
+ GNUNET_break (0);
+ return;
+ }
+ tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + mlen);
+ usm = (struct GNUNET_EXIT_UdpServiceMessage *) &tnq[1];
+ usm->header.size = htons ((uint16_t) mlen);
+ usm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_UDP_TO_SERVICE);
+ /* if the source port is below 32000, we assume it has a special
+ meaning; if not, we pick a random port (this is a heuristic) */
+ usm->source_port = (ntohs (udp->spt) < 32000) ? udp->spt : 0;
+ usm->destination_port = udp->dpt;
+ usm->service_descriptor = destination->details.service_destination.service_descriptor;
+ memcpy (&usm[1],
+ &udp[1],
+ payload_length - sizeof (struct udp_packet));
}
else
{
- tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + 42);
- // FIXME: build message!
+ struct GNUNET_EXIT_UdpInternetMessage *uim;
+ struct in_addr *ip4dst;
+ struct in6_addr *ip6dst;
+ void *payload;
+
+ mlen = sizeof (struct GNUNET_EXIT_UdpInternetMessage) +
+ alen + payload_length - sizeof (struct udp_packet);
+ if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+ {
+ GNUNET_break (0);
+ return;
+ }
+ tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) +
+ mlen);
+ uim = (struct GNUNET_EXIT_UdpInternetMessage *) &tnq[1];
+ uim->header.size = htons ((uint16_t) mlen);
+ uim->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_UDP_TO_INTERNET);
+ uim->af = htonl (destination->details.exit_destination.af);
+ uim->source_port = (ntohs (udp->spt) < 32000) ? udp->spt : 0;
+ uim->destination_port = udp->dpt;
+ switch (destination->details.exit_destination.af)
+ {
+ case AF_INET:
+ ip4dst = (struct in_addr *) &uim[1];
+ *ip4dst = destination->details.exit_destination.ip.v4;
+ payload = &ip4dst[1];
+ break;
+ case AF_INET6:
+ ip6dst = (struct in6_addr *) &uim[1];
+ *ip6dst = destination->details.exit_destination.ip.v6;
+ payload = &ip6dst[1];
+ break;
+ default:
+ GNUNET_assert (0);
+ }
+ memcpy (payload,
+ &udp[1],
+ payload_length - sizeof (struct udp_packet));
}
break;
case IPPROTO_TCP:
- if (destination->is_service)
+ if (is_new)
{
- tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + 42);
- // FIXME: build message!
+ if (destination->is_service)
+ {
+ struct GNUNET_EXIT_TcpServiceStartMessage *tsm;
+
+ mlen = sizeof (struct GNUNET_EXIT_TcpServiceStartMessage) +
+ payload_length - sizeof (struct tcp_packet);
+ if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+ {
+ GNUNET_break (0);
+ return;
+ }
+ tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + mlen);
+ tsm = (struct GNUNET_EXIT_TcpServiceStartMessage *) &tnq[1];
+ tsm->header.size = htons ((uint16_t) mlen);
+ tsm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_TO_SERVICE_START);
+ tsm->reserved = htonl (0);
+ tsm->service_descriptor = destination->details.service_destination.service_descriptor;
+ tsm->tcp_header = *tcp;
+ memcpy (&tsm[1],
+ &tcp[1],
+ payload_length - sizeof (struct tcp_packet));
+ }
+ else
+ {
+ struct GNUNET_EXIT_TcpInternetStartMessage *tim;
+ struct in_addr *ip4dst;
+ struct in6_addr *ip6dst;
+ void *payload;
+
+ mlen = sizeof (struct GNUNET_EXIT_TcpInternetStartMessage) +
+ alen + payload_length - sizeof (struct tcp_packet);
+ if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+ {
+ GNUNET_break (0);
+ return;
+ }
+ tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + mlen);
+ tim = (struct GNUNET_EXIT_TcpInternetStartMessage *) &tnq[1];
+ tim->header.size = htons ((uint16_t) mlen);
+ tim->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_TO_INTERNET_START);
+ tim->af = htonl (destination->details.exit_destination.af);
+ tim->tcp_header = *tcp;
+ switch (destination->details.exit_destination.af)
+ {
+ case AF_INET:
+ ip4dst = (struct in_addr *) &tim[1];
+ *ip4dst = destination->details.exit_destination.ip.v4;
+ payload = &ip4dst[1];
+ break;
+ case AF_INET6:
+ ip6dst = (struct in6_addr *) &tim[1];
+ *ip6dst = destination->details.exit_destination.ip.v6;
+ payload = &ip6dst[1];
+ break;
+ default:
+ GNUNET_assert (0);
+ }
+ memcpy (payload,
+ &tcp[1],
+ payload_length - sizeof (struct tcp_packet));
+ }
}
else
{
- tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + 42);
- // FIXME: build message!
- }
+ struct GNUNET_EXIT_TcpDataMessage *tdm;
+
+ mlen = sizeof (struct GNUNET_EXIT_TcpDataMessage) +
+ alen + payload_length - sizeof (struct tcp_packet);
+ if (mlen >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+ {
+ GNUNET_break (0);
+ return;
+ }
+ tnq = GNUNET_malloc (sizeof (struct TunnelMessageQueueEntry) + mlen);
+ tdm = (struct GNUNET_EXIT_TcpDataMessage *) &tnq[1];
+ tdm->header.size = htons ((uint16_t) mlen);
+ tdm->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_TCP_DATA);
+ tdm->reserved = htonl (0);
+ tdm->tcp_header = *tcp;
+ memcpy (&tdm[1],
+ &tcp[1],
+ payload_length - sizeof (struct tcp_packet));
+ }
break;
default:
/* not supported above, how can we get here !? */
}
-
/**
* Receive packets from the helper-process (someone send to the local
* virtual tunnel interface). Find the destination mapping, and if it
const struct GNUNET_MessageHeader *message,
const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
{
- // FIXME: parse message, build IP packet, give to TUN!
-#if 0
- GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
- struct remote_addr *s = (struct remote_addr *) desc;
- struct udp_pkt *pkt = (struct udp_pkt *) (desc + 1);
- const struct GNUNET_PeerIdentity *other = sender;
struct TunnelState *ts = *tunnel_ctx;
+ const struct GNUNET_EXIT_UdpReplyMessage *reply;
+ size_t mlen;
- if (16 == ts->addrlen)
+ mlen = ntohs (message->size);
+ if (mlen < sizeof (struct GNUNET_EXIT_UdpReplyMessage))
{
- size_t size =
- sizeof (struct ip6_udp) + ntohs (pkt->len) - 1 -
- sizeof (struct udp_pkt);
-
- struct ip6_udp *pkt6 = alloca (size);
-
- GNUNET_assert (pkt6 != NULL);
-
- if (ntohs (message->type) == GNUNET_MESSAGE_TYPE_VPN_SERVICE_UDP_BACK)
- new_ip6addr (&pkt6->ip6_hdr.sadr, &other->hashPubKey, desc);
- else
- new_ip6addr_remote (&pkt6->ip6_hdr.sadr, s->addr, s->addrlen);
-
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Relaying calc:%d gnu:%d udp:%d bytes!\n", size,
- ntohs (message->size), ntohs (pkt->len));
-
- pkt6->shdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
- pkt6->shdr.size = htons (size);
-
- pkt6->tun.flags = 0;
- pkt6->tun.type = htons (0x86dd);
-
- pkt6->ip6_hdr.version = 6;
- pkt6->ip6_hdr.tclass_h = 0;
- pkt6->ip6_hdr.tclass_l = 0;
- pkt6->ip6_hdr.flowlbl = 0;
- pkt6->ip6_hdr.paylgth = pkt->len;
- pkt6->ip6_hdr.nxthdr = IPPROTO_UDP;
- pkt6->ip6_hdr.hoplmt = 0xff;
-
- {
- char *ipv6addr;
-
- GNUNET_assert (GNUNET_OK ==
- GNUNET_CONFIGURATION_get_value_string (cfg, "vpn",
- "IPV6ADDR",
- &ipv6addr));
- inet_pton (AF_INET6, ipv6addr, &pkt6->ip6_hdr.dadr);
- GNUNET_free (ipv6addr);
- }
- memcpy (&pkt6->udp_hdr, pkt, ntohs (pkt->len));
-
- GNUNET_HashCode *key = address6_mapping_exists (&pkt6->ip6_hdr.sadr);
-
- GNUNET_assert (key != NULL);
-
- struct map_entry *me = GNUNET_CONTAINER_multihashmap_get (hashmap, key);
-
- GNUNET_CONTAINER_heap_update_cost (heap, me->heap_node,
- GNUNET_TIME_absolute_get ().abs_value);
-
- GNUNET_free (key);
-
- GNUNET_assert (me != NULL);
-
- pkt6->udp_hdr.crc = 0;
- uint32_t sum = 0;
-
- sum =
- GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & pkt6->ip6_hdr.sadr, 16);
- sum =
- GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & pkt6->ip6_hdr.dadr, 16);
- uint32_t tmp = (pkt6->udp_hdr.len & 0xffff);
-
- sum = GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & tmp, 4);
- tmp = htons (((pkt6->ip6_hdr.nxthdr & 0x00ff)));
- sum = GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & tmp, 4);
-
- sum =
- GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & pkt6->udp_hdr,
- ntohs (pkt->len));
- pkt6->udp_hdr.crc = GNUNET_CRYPTO_crc16_finish (sum);
-
- (void) GNUNET_HELPER_send (helper_handle,
- &pkt6->shdr,
- GNUNET_YES,
- NULL, NULL);
+ GNUNET_break_op (0);
+ return GNUNET_SYSERR;
}
- else
+ if (NULL == ts->heap_node)
{
- size_t size =
- sizeof (struct ip_udp) + ntohs (pkt->len) - 1 - sizeof (struct udp_pkt);
-
- struct ip_udp *pkt4 = alloca (size);
-
- GNUNET_assert (pkt4 != NULL);
-
- GNUNET_assert (ntohs (message->type) ==
- GNUNET_MESSAGE_TYPE_VPN_REMOTE_UDP_BACK);
- uint32_t sadr;
-
- new_ip4addr_remote ((unsigned char *) &sadr, s->addr, s->addrlen);
- pkt4->ip_hdr.sadr.s_addr = sadr;
-
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Relaying calc:%d gnu:%d udp:%d bytes!\n", size,
- ntohs (message->size), ntohs (pkt->len));
-
- pkt4->shdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
- pkt4->shdr.size = htons (size);
-
- pkt4->tun.flags = 0;
- pkt4->tun.type = htons (0x0800);
-
- pkt4->ip_hdr.version = 4;
- pkt4->ip_hdr.hdr_lngth = 5;
- pkt4->ip_hdr.diff_serv = 0;
- pkt4->ip_hdr.tot_lngth = htons (20 + ntohs (pkt->len));
- pkt4->ip_hdr.ident = 0;
- pkt4->ip_hdr.flags = 0;
- pkt4->ip_hdr.frag_off = 0;
- pkt4->ip_hdr.ttl = 255;
- pkt4->ip_hdr.proto = IPPROTO_UDP;
- pkt4->ip_hdr.chks = 0; /* Will be calculated later */
-
+ GNUNET_break_op (0);
+ return GNUNET_SYSERR;
+ }
+ reply = (const struct GNUNET_EXIT_UdpReplyMessage *) message;
+ mlen -= sizeof (struct GNUNET_EXIT_UdpReplyMessage);
+ switch (ts->af)
+ {
+ case AF_INET:
{
- char *ipv4addr;
- uint32_t dadr;
-
- GNUNET_assert (GNUNET_OK ==
- GNUNET_CONFIGURATION_get_value_string (cfg, "vpn",
- "IPV4ADDR",
- &ipv4addr));
- inet_pton (AF_INET, ipv4addr, &dadr);
- GNUNET_free (ipv4addr);
- pkt4->ip_hdr.dadr.s_addr = dadr;
+ size_t size = sizeof (struct ip4_header)
+ + sizeof (struct udp_packet)
+ + sizeof (struct GNUNET_MessageHeader) +
+ sizeof (struct tun_header) +
+ mlen;
+ {
+ char buf[size];
+ struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
+ struct tun_header *tun = (struct tun_header*) &msg[1];
+ struct ip4_header *ipv4 = (struct ip4_header *) &tun[1];
+ struct udp_packet *udp = (struct udp_packet *) &ipv4[1];
+ msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
+ msg->size = htons (size);
+ tun->flags = htons (0);
+ tun->proto = htons (ETH_P_IPV4);
+ ipv4->version = 4;
+ ipv4->header_length = sizeof (struct ip4_header) / 4;
+ ipv4->diff_serv = 0;
+ ipv4->total_length = htons (sizeof (struct ip4_header) +
+ sizeof (struct udp_packet) +
+ mlen);
+ ipv4->identification = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
+ UINT16_MAX + 1);
+ ipv4->flags = 0;
+ ipv4->fragmentation_offset = 0;
+ ipv4->ttl = 255;
+ ipv4->protocol = IPPROTO_UDP;
+ ipv4->checksum = 0;
+ ipv4->source_address = ts->destination_ip.v4;
+ ipv4->destination_address = ts->source_ip.v4;
+ ipv4->checksum =
+ GNUNET_CRYPTO_crc16_n (ipv4, sizeof (struct ip4_header));
+ if (0 == ntohs (reply->source_port))
+ udp->spt = htons (ts->destination_port);
+ else
+ udp->spt = reply->source_port;
+ if (0 == ntohs (reply->destination_port))
+ udp->dpt = htons (ts->source_port);
+ else
+ udp->dpt = reply->destination_port;
+ udp->len = htons (mlen + sizeof (struct udp_packet));
+ udp->crc = 0; // FIXME: optional, but we might want to calculate this one anyway
+ memcpy (&udp[1],
+ &reply[1],
+ mlen);
+ (void) GNUNET_HELPER_send (helper_handle,
+ msg,
+ GNUNET_YES,
+ NULL, NULL);
+ }
}
- memcpy (&pkt4->udp_hdr, pkt, ntohs (pkt->len));
-
- GNUNET_HashCode *key = address4_mapping_exists (pkt4->ip_hdr.sadr.s_addr);
-
- GNUNET_assert (key != NULL);
-
- struct map_entry *me = GNUNET_CONTAINER_multihashmap_get (hashmap, key);
-
- GNUNET_CONTAINER_heap_update_cost (heap, me->heap_node,
- GNUNET_TIME_absolute_get ().abs_value);
-
- GNUNET_free (key);
-
- GNUNET_assert (me != NULL);
-
- pkt4->udp_hdr.crc = 0; /* Optional for IPv4 */
-
- pkt4->ip_hdr.chks =
- GNUNET_CRYPTO_crc16_n ((uint16_t *) & pkt4->ip_hdr, 5 * 4);
-
- (void) GNUNET_HELPER_send (helper_handle,
- &pkt4->shdr,
- GNUNET_YES,
- NULL, NULL);
+ break;
+ case AF_INET6:
+ {
+ size_t size = sizeof (struct ip6_header)
+ + sizeof (struct udp_packet)
+ + sizeof (struct GNUNET_MessageHeader) +
+ sizeof (struct tun_header) +
+ mlen;
+ {
+ char buf[size];
+ struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
+ struct tun_header *tun = (struct tun_header*) &msg[1];
+ struct ip6_header *ipv6 = (struct ip6_header *) &tun[1];
+ struct udp_packet *udp = (struct udp_packet *) &ipv6[1];
+ msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
+ msg->size = htons (size);
+ tun->flags = htons (0);
+ tun->proto = htons (ETH_P_IPV6);
+ ipv6->traffic_class_h = 0;
+ ipv6->version = 6;
+ ipv6->traffic_class_l = 0;
+ ipv6->flow_label = 0;
+ ipv6->payload_length = htons (sizeof (struct udp_packet) + sizeof (struct ip6_header) + mlen);
+ ipv6->next_header = IPPROTO_UDP;
+ ipv6->hop_limit = 255;
+ ipv6->source_address = ts->destination_ip.v6;
+ ipv6->destination_address = ts->source_ip.v6;
+ if (0 == ntohs (reply->source_port))
+ udp->spt = htons (ts->destination_port);
+ else
+ udp->spt = reply->source_port;
+ if (0 == ntohs (reply->destination_port))
+ udp->dpt = htons (ts->source_port);
+ else
+ udp->dpt = reply->destination_port;
+ udp->len = htons (mlen + sizeof (struct udp_packet));
+ udp->crc = 0;
+ memcpy (&udp[1],
+ &reply[1],
+ mlen);
+ {
+ uint32_t sum = 0;
+ sum =
+ GNUNET_CRYPTO_crc16_step (sum, &ipv6->source_address,
+ sizeof (struct in6_addr) * 2);
+ uint32_t tmp = udp->len;
+ sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint32_t));
+ tmp = htons (IPPROTO_UDP);
+ sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint32_t));
+ sum = GNUNET_CRYPTO_crc16_step (sum,
+ udp,
+ ntohs (udp->len));
+ udp->crc = GNUNET_CRYPTO_crc16_finish (sum);
+ }
+ (void) GNUNET_HELPER_send (helper_handle,
+ msg,
+ GNUNET_YES,
+ NULL, NULL);
+ }
+ }
+ break;
+ default:
+ GNUNET_assert (0);
}
+#if 0
+ // FIXME: refresh entry to avoid expiration...
+ struct map_entry *me = GNUNET_CONTAINER_multihashmap_get (hashmap, key);
+
+ GNUNET_CONTAINER_heap_update_cost (heap, me->heap_node,
+ GNUNET_TIME_absolute_get ().abs_value);
+
#endif
return GNUNET_OK;
}
const struct GNUNET_MessageHeader *message,
const struct GNUNET_ATS_Information *atsi GNUNET_UNUSED)
{
+ struct TunnelState *ts = *tunnel_ctx;
+ const struct GNUNET_EXIT_TcpDataMessage *data;
+ size_t mlen;
+
+ mlen = ntohs (message->size);
+ if (mlen < sizeof (struct GNUNET_EXIT_TcpDataMessage))
+ {
+ GNUNET_break_op (0);
+ return GNUNET_SYSERR;
+ }
+ if (NULL == ts->heap_node)
+ {
+ GNUNET_break_op (0);
+ return GNUNET_SYSERR;
+ }
+ data = (const struct GNUNET_EXIT_TcpDataMessage *) message;
+ mlen -= sizeof (struct GNUNET_EXIT_TcpDataMessage);
+ switch (ts->af)
+ {
+ case AF_INET:
+ {
+ size_t size = sizeof (struct ip4_header)
+ + sizeof (struct tcp_packet)
+ + sizeof (struct GNUNET_MessageHeader) +
+ sizeof (struct tun_header) +
+ mlen;
+ {
+ char buf[size];
+ struct GNUNET_MessageHeader *msg = (struct GNUNET_MessageHeader *) buf;
+ struct tun_header *tun = (struct tun_header*) &msg[1];
+ struct ip4_header *ipv4 = (struct ip4_header *) &tun[1];
+ struct tcp_packet *tcp = (struct tcp_packet *) &ipv4[1];
+ msg->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER);
+ msg->size = htons (size);
+ tun->flags = htons (0);
+ tun->proto = htons (ETH_P_IPV4);
+ ipv4->version = 4;
+ ipv4->header_length = sizeof (struct ip4_header) / 4;
+ ipv4->diff_serv = 0;
+ ipv4->total_length = htons (sizeof (struct ip4_header) +
+ sizeof (struct tcp_packet) +
+ mlen);
+ ipv4->identification = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
+ UINT16_MAX + 1);
+ ipv4->flags = 0;
+ ipv4->fragmentation_offset = 0;
+ ipv4->ttl = 255;
+ ipv4->protocol = IPPROTO_TCP;
+ ipv4->checksum = 0;
+ ipv4->source_address = ts->destination_ip.v4;
+ ipv4->destination_address = ts->source_ip.v4;
+ ipv4->checksum =
+ GNUNET_CRYPTO_crc16_n (ipv4, sizeof (struct ip4_header));
+ *tcp = data->tcp_header;
+ tcp->spt = htons (ts->destination_port);
+ tcp->dpt = htons (ts->source_port);
+ tcp->crc = 0;
+ memcpy (&tcp[1],
+ &data[1],
+ mlen);
+ {
+ uint32_t sum = 0;
+ uint32_t tmp;
+
+ sum = GNUNET_CRYPTO_crc16_step (sum,
+ &ipv4->source_address,
+ 2 * sizeof (struct in_addr));
+ tmp = htonl ((IPPROTO_TCP << 16) | (mlen + sizeof (struct tcp_packet)));
+ sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint32_t));
+ sum = GNUNET_CRYPTO_crc16_step (sum, tcp, mlen + sizeof (struct tcp_packet));
+ tcp->crc = GNUNET_CRYPTO_crc16_finish (sum);
+ }
+ (void) GNUNET_HELPER_send (helper_handle,
+ msg,
+ GNUNET_YES,
+ NULL, NULL);
+ }
+ }
+ break;
+ case AF_INET6:
+ break;
+ default:
+ GNUNET_assert (0);
+ }
// FIXME: parse message, build IP packet, give to TUN!
#if 0
GNUNET_HashCode *desc = (GNUNET_HashCode *) (message + 1);
GNUNET_assert (me != NULL);
pkt6->tcp_hdr.crc = 0;
- uint32_t sum = 0;
- uint32_t tmp;
- sum =
- GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & pkt6->ip6_hdr.sadr, 16);
+ uint32_t sum = 0;
+ uint32_t tmp;
+
+ sum = GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & pkt6->ip6_hdr.sadr, 16);
sum =
GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & pkt6->ip6_hdr.dadr, 16);
tmp = htonl (pktlen);
ntohs (pkt6->ip6_hdr.paylgth));
pkt6->tcp_hdr.crc = GNUNET_CRYPTO_crc16_finish (sum);
+
(void) GNUNET_HELPER_send (helper_handle,
&pkt6->shdr,
GNUNET_YES,
GNUNET_assert (me != NULL);
pkt4->tcp_hdr.crc = 0;
- uint32_t sum = 0;
- uint32_t tmp;
-
- sum = GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) &pkt4->ip_hdr.sadr, 4);
- sum = GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) &pkt4->ip_hdr.dadr, 4);
-
- tmp = (0x06 << 16) | (0xffff & pktlen); // 0x06 for TCP?
-
- tmp = htonl (tmp);
-
- sum = GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & tmp, 4);
-
- sum = GNUNET_CRYPTO_crc16_step (sum, (uint16_t *) & pkt4->tcp_hdr, pktlen);
- pkt4->tcp_hdr.crc = GNUNET_CRYPTO_crc16_finish (sum);
-
- pkt4->ip_hdr.chks =
- GNUNET_CRYPTO_crc16_n ((uint16_t *) & pkt4->ip_hdr, 5 * 4);
(void) GNUNET_HELPER_send (helper_handle,
&pkt4->shdr,
NULL, NULL);
}
+#endif
+
+#if 0
+ // FIXME: refresh entry to avoid expiration...
+ struct map_entry *me = GNUNET_CONTAINER_multihashmap_get (hashmap, key);
+
+ GNUNET_CONTAINER_heap_update_cost (heap, me->heap_node,
+ GNUNET_TIME_absolute_get ().abs_value);
+
#endif
return GNUNET_OK;
}
static int
allocate_v4_address (struct in_addr *v4)
{
- // FIXME: implement!
- return GNUNET_SYSERR;
+ const char *ipv4addr = vpn_argv[4];
+ const char *ipv4mask = vpn_argv[5];
+ struct in_addr addr;
+ struct in_addr mask;
+ struct in_addr rnd;
+ GNUNET_HashCode key;
+ unsigned int tries;
+
+ GNUNET_assert (1 == inet_pton (AF_INET, ipv4addr, &addr));
+ GNUNET_assert (1 == inet_pton (AF_INET, ipv4mask, &mask));
+ /* Given 192.168.0.1/255.255.0.0, we want a mask
+ of '192.168.255.255', thus: */
+ mask.s_addr = addr.s_addr | ~mask.s_addr;
+ tries = 0;
+ do
+ {
+ tries++;
+ if (tries > 16)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Failed to find unallocated IPv4 address in VPN's range\n"));
+ return GNUNET_SYSERR;
+ }
+ /* Pick random IPv4 address within the subnet, except 'addr' or 'mask' itself */
+ rnd.s_addr = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
+ UINT32_MAX);
+ v4->s_addr = (addr.s_addr | rnd.s_addr) & mask.s_addr;
+ get_destination_key_from_ip (AF_INET,
+ v4,
+ &key);
+ }
+ while ( (GNUNET_YES ==
+ GNUNET_CONTAINER_multihashmap_contains (destination_map,
+ &key)) ||
+ (v4->s_addr == addr.s_addr) ||
+ (v4->s_addr == mask.s_addr) );
+ return GNUNET_OK;
}
* GNUNET_SYSERR on error
*/
static int
-allocate_v6_address (struct in6_addr *v4)
+allocate_v6_address (struct in6_addr *v6)
{
- // FIXME: implement!
- return GNUNET_SYSERR;
-}
-
-
-/**
- * Notify the client about the result of its request.
- *
- * @param client client to notify
- * @param request_id original request ID to include in response
- * @param result_af resulting address family
- * @param addr resulting IP address
- */
-static void
-send_client_reply (struct GNUNET_SERVER_Client *client,
- uint64_t request_id,
- int result_af,
- const void *addr)
-{
- char buf[sizeof (struct RedirectToIpResponseMessage) + sizeof (struct in6_addr)];
- struct RedirectToIpResponseMessage *res;
- size_t rlen;
-
- switch (result_af)
- {
- case AF_INET:
- rlen = sizeof (struct in_addr);
- break;
- case AF_INET6:
- rlen = sizeof (struct in6_addr);
- break;
- case AF_UNSPEC:
- rlen = 0;
- break;
- default:
- GNUNET_assert (0);
- return;
- }
- res = (struct RedirectToIpResponseMessage *) buf;
- res->header.size = htons (sizeof (struct RedirectToIpResponseMessage) + rlen);
- res->header.type = htons (GNUNET_MESSAGE_TYPE_VPN_CLIENT_USE_IP);
- res->result_af = htonl (result_af);
- res->request_id = request_id;
- memcpy (&res[1], addr, rlen);
- GNUNET_SERVER_notification_context_add (nc, client);
- GNUNET_SERVER_notification_context_unicast (nc,
- client,
- &res->header,
- GNUNET_NO);
-}
-
-
-/**
- * Method called whenever a peer has disconnected from the tunnel.
- *
- * @param cls closure
- * @param peer peer identity the tunnel stopped working with
- */
-static void
-tunnel_peer_disconnect_handler (void *cls,
- const struct
- GNUNET_PeerIdentity * peer)
-{
- /* FIXME: should we do anything here?
- - stop transmitting to the tunnel (start queueing?)
- - possibly destroy the tunnel entirely (unless service tunnel?)
- */
-}
-
-
-/**
- * Method called whenever a peer has connected to the tunnel. Notifies
- * the waiting client that the tunnel is now up.
- *
- * @param cls closure
- * @param peer peer identity the tunnel was created to, NULL on timeout
- * @param atsi performance data for the connection
- */
-static void
-tunnel_peer_connect_handler (void *cls,
- const struct GNUNET_PeerIdentity
- * peer,
- const struct
- GNUNET_ATS_Information * atsi)
-{
- struct TunnelState *ts = cls;
-
- if (NULL == ts->client)
- return; /* nothing to do */
- send_client_reply (ts->client,
- ts->request_id,
- ts->af,
- &ts->destination_ip);
- GNUNET_SERVER_client_drop (ts->client);
- ts->client = NULL;
+ const char *ipv6addr = vpn_argv[2];
+ struct in6_addr addr;
+ struct in6_addr mask;
+ struct in6_addr rnd;
+ int i;
+ GNUNET_HashCode key;
+ unsigned int tries;
+
+ GNUNET_assert (1 == inet_pton (AF_INET6, ipv6addr, &addr));
+ GNUNET_assert (ipv6prefix < 128);
+ /* Given ABCD::/96, we want a mask of 'ABCD::FFFF:FFFF,
+ thus: */
+ mask = addr;
+ for (i=127;i>=128-ipv6prefix;i--)
+ mask.s6_addr[i / 8] |= (1 << (i % 8));
+
+ /* Pick random IPv6 address within the subnet, except 'addr' or 'mask' itself */
+ tries = 0;
+ do
+ {
+ tries++;
+ if (tries > 16)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Failed to find unallocated IPv6 address in VPN's range\n"));
+ return GNUNET_SYSERR;
+
+ }
+ for (i=0;i<16;i++)
+ {
+ rnd.s6_addr[i] = (unsigned char) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
+ 256);
+ v6->s6_addr[i]
+ = (addr.s6_addr[i] | rnd.s6_addr[i]) & mask.s6_addr[i];
+ }
+ get_destination_key_from_ip (AF_INET6,
+ v6,
+ &key);
+ }
+ while ( (GNUNET_YES ==
+ GNUNET_CONTAINER_multihashmap_contains (destination_map,
+ &key)) ||
+ (0 == memcmp (v6,
+ &addr,
+ sizeof (struct in6_addr))) ||
+ (0 == memcmp (v6,
+ &mask,
+ sizeof (struct in6_addr))) );
+ return GNUNET_OK;
}
char *ipv4mask;
struct in_addr v4;
struct in6_addr v6;
- unsigned long long ipv6prefix;
cfg = cfg_;
if (GNUNET_OK !=