/*
This file is part of GNUnet.
- (C) 2009, 2010 Christian Grothoff (and other contributing authors)
+ (C) 2009, 2010, 2011 Christian Grothoff (and other contributing authors)
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
Boston, MA 02111-1307, USA.
*/
-/*
- * Parts of this file have been adapted from the Transmission project:
- * Originally licensed by the GPL version 2.
- * Copyright (C) 2007-2009 Charles Kerr <charles@transmissionbt.com>
- */
-
/**
* @file nat/nat.c
* @brief Library handling UPnP and NAT-PMP port forwarding and
* external IP address retrieval
- *
* @author Milan Bouchet-Valat
+ * @author Christian Grothoff
*/
#include "platform.h"
#include "gnunet_util_lib.h"
+#include "gnunet_resolver_service.h"
#include "gnunet_nat_lib.h"
#include "nat.h"
-#include "natpmp.h"
-#include "upnp.h"
+
+#define LOG(kind,...) GNUNET_log_from (kind, "nat", __VA_ARGS__)
/**
- * Handle for active NAT registrations.
+ * How often do we scan for changes in our IP address from our local
+ * interfaces?
*/
-struct GNUNET_NAT_Handle
+#define IFC_SCAN_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)
+
+/**
+ * How often do we scan for changes in how our hostname resolves?
+ */
+#define HOSTNAME_DNS_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 20)
+
+
+/**
+ * How often do we scan for changes in how our external (dyndns) hostname resolves?
+ */
+#define DYNDNS_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 7)
+
+/**
+ * How long until we give up trying to resolve our own hostname?
+ */
+#define HOSTNAME_RESOLVE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
+
+
+/**
+ * Where did the given local address originate from?
+ * To be used for debugging as well as in the future
+ * to remove all addresses from a certain source when
+ * we reevaluate the source.
+ */
+enum LocalAddressSource
+{
+ /**
+ * Address was obtained by DNS resolution of the external hostname
+ * given in the configuration (i.e. hole-punched DynDNS setup).
+ */
+ LAL_EXTERNAL_IP,
+
+ /**
+ * Address was obtained by looking up our own hostname in DNS.
+ */
+ LAL_HOSTNAME_DNS,
+
+ /**
+ * Address was obtained by scanning our hosts's network interfaces
+ * and taking their address (no DNS involved).
+ */
+ LAL_INTERFACE_ADDRESS,
+
+ /**
+ * Addresses we were explicitly bound to.
+ */
+ LAL_BINDTO_ADDRESS,
+
+ /**
+ * Addresses from UPnP or PMP
+ */
+ LAL_UPNP,
+
+ /**
+ * End of the list.
+ */
+ LAL_END
+};
+
+
+/**
+ * List of local addresses that we currently deem valid. Actual
+ * struct is followed by the 'struct sockaddr'. Note that the code
+ * intentionally makes no attempt to ensure that a particular address
+ * is only listed once (especially since it may come from different
+ * sources, and the source is an "internal" construct).
+ */
+struct LocalAddressList
{
/**
- * Handle for UPnP operations.
+ * This is a linked list.
*/
- GNUNET_NAT_UPNP_Handle *upnp;
+ struct LocalAddressList *next;
/**
- * Handle for NAT PMP operations.
+ * Previous entry.
*/
- GNUNET_NAT_NATPMP_Handle *natpmp;
+ struct LocalAddressList *prev;
/**
- * Scheduler.
+ * Number of bytes of address that follow.
*/
- struct GNUNET_SCHEDULER_Handle *sched;
+ socklen_t addrlen;
/**
- * LAN address as passed by the caller
+ * Origin of the local address.
*/
- struct sockaddr *local_addr;
+ enum LocalAddressSource source;
+};
+
+
+/**
+ * Handle for miniupnp-based NAT traversal actions.
+ */
+struct MiniList
+{
/**
- * External address as reported by NAT box
+ * Doubly-linked list.
*/
- struct sockaddr *ext_addr;
+ struct MiniList *next;
/**
- * External address and port where packets are redirected
+ * Doubly-linked list.
*/
- struct sockaddr *contact_addr;
+ struct MiniList *prev;
- GNUNET_NAT_AddressCallback callback;
+ /**
+ * Handle to mini-action.
+ */
+ struct GNUNET_NAT_MiniHandle *mini;
+
+ /**
+ * Local port number that was mapped.
+ */
+ uint16_t port;
+
+};
+
+
+/**
+ * Handle for active NAT registrations.
+ */
+struct GNUNET_NAT_Handle
+{
+
+ /**
+ * Configuration to use.
+ */
+ const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+ /**
+ * Function to call when we learn about a new address.
+ */
+ GNUNET_NAT_AddressCallback address_callback;
+
+ /**
+ * Function to call when we notice another peer asking for
+ * connection reversal.
+ */
+ GNUNET_NAT_ReversalCallback reversal_callback;
/**
* Closure for 'callback'.
*/
void *callback_cls;
- GNUNET_SCHEDULER_TaskIdentifier pulse_timer;
+ /**
+ * Handle for (DYN)DNS lookup of our external IP.
+ */
+ struct GNUNET_RESOLVER_RequestHandle *ext_dns;
+
+ /**
+ * Handle for request of hostname resolution, non-NULL if pending.
+ */
+ struct GNUNET_RESOLVER_RequestHandle *hostname_dns;
+
+ /**
+ * stdout pipe handle for the gnunet-helper-nat-server process
+ */
+ struct GNUNET_DISK_PipeHandle *server_stdout;
+
+ /**
+ * stdout file handle (for reading) for the gnunet-helper-nat-server process
+ */
+ const struct GNUNET_DISK_FileHandle *server_stdout_handle;
+
+ /**
+ * Linked list of currently valid addresses (head).
+ */
+ struct LocalAddressList *lal_head;
+
+ /**
+ * Linked list of currently valid addresses (tail).
+ */
+ struct LocalAddressList *lal_tail;
+
+ /**
+ * How long do we wait for restarting a crashed gnunet-helper-nat-server?
+ */
+ struct GNUNET_TIME_Relative server_retry_delay;
+
+ /**
+ * ID of select gnunet-helper-nat-server stdout read task
+ */
+ GNUNET_SCHEDULER_TaskIdentifier server_read_task;
+
+ /**
+ * ID of interface IP-scan task
+ */
+ GNUNET_SCHEDULER_TaskIdentifier ifc_task;
+
+ /**
+ * ID of hostname DNS lookup task
+ */
+ GNUNET_SCHEDULER_TaskIdentifier hostname_task;
+
+ /**
+ * ID of DynDNS lookup task
+ */
+ GNUNET_SCHEDULER_TaskIdentifier dns_task;
+
+ /**
+ * ID of task to add addresses from bind.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier bind_task;
+
+ /**
+ * How often do we scan for changes in our IP address from our local
+ * interfaces?
+ */
+ struct GNUNET_TIME_Relative ifc_scan_frequency;
+
+ /**
+ * How often do we scan for changes in how our hostname resolves?
+ */
+ struct GNUNET_TIME_Relative hostname_dns_frequency;
+
+ /**
+ * How often do we scan for changes in how our external (dyndns) hostname resolves?
+ */
+ struct GNUNET_TIME_Relative dyndns_frequency;
- enum GNUNET_NAT_PortState natpmp_status;
+ /**
+ * The process id of the server process (if behind NAT)
+ */
+ struct GNUNET_OS_Process *server_proc;
- enum GNUNET_NAT_PortState upnp_status;
+ /**
+ * LAN address as passed by the caller (array).
+ */
+ struct sockaddr **local_addrs;
- int is_enabled;
+ /**
+ * Length of the 'local_addrs'.
+ */
+ socklen_t *local_addrlens;
- int should_change;
+ /**
+ * List of handles for UPnP-traversal, one per local port (if
+ * not IPv6-only).
+ */
+ struct MiniList *mini_head;
- int port_mapped;
+ /**
+ * List of handles for UPnP-traversal, one per local port (if
+ * not IPv6-only).
+ */
+ struct MiniList *mini_tail;
- int did_warn;
+ /**
+ * Number of entries in 'local_addrs' array.
+ */
+ unsigned int num_local_addrs;
- uint16_t public_port;
+ /**
+ * Our external address (according to config, UPnP may disagree...),
+ * in dotted decimal notation, IPv4-only. Or NULL if not known.
+ */
+ char *external_address;
+
+ /**
+ * Presumably our internal address (according to config)
+ */
+ char *internal_address;
+
+ /**
+ * Is this transport configured to be behind a NAT?
+ */
+ int behind_nat;
+
+ /**
+ * Has the NAT been punched? (according to config)
+ */
+ int nat_punched;
+
+ /**
+ * Is this transport configured to allow connections to NAT'd peers?
+ */
+ int enable_nat_client;
+
+ /**
+ * Should we run the gnunet-helper-nat-server?
+ */
+ int enable_nat_server;
+
+ /**
+ * Are we allowed to try UPnP/PMP for NAT traversal?
+ */
+ int enable_upnp;
+
+ /**
+ * Should we use local addresses (loopback)? (according to config)
+ */
+ int use_localaddresses;
+
+ /**
+ * Should we return local addresses to clients
+ */
+ int return_localaddress;
+
+ /**
+ * Should we do a DNS lookup of our hostname to find out our own IP?
+ */
+ int use_hostname;
+
+ /**
+ * Is using IPv6 disabled?
+ */
+ int disable_ipv6;
+
+ /**
+ * Is this TCP or UDP?
+ */
+ int is_tcp;
+
+ /**
+ * Port we advertise to the outside.
+ */
+ uint16_t adv_port;
};
-#ifdef DEBUG
-static const char *
-get_nat_state_str (enum GNUNET_NAT_PortState state)
+
+/**
+ * Try to start the gnunet-helper-nat-server (if it is not
+ * already running).
+ *
+ * @param h handle to NAT
+ */
+static void
+start_gnunet_nat_server (struct GNUNET_NAT_Handle *h);
+
+
+/**
+ * Remove all addresses from the list of 'local' addresses
+ * that originated from the given source.
+ *
+ * @param h handle to NAT
+ * @param src source that identifies addresses to remove
+ */
+static void
+remove_from_address_list_by_source (struct GNUNET_NAT_Handle *h,
+ enum LocalAddressSource src)
{
- switch (state)
- {
- case GNUNET_NAT_PORT_MAPPING:
- return "Starting";
- case GNUNET_NAT_PORT_MAPPED:
- return "Forwarded";
- case GNUNET_NAT_PORT_UNMAPPING:
- return "Stopping";
- case GNUNET_NAT_PORT_UNMAPPED:
- return "Not forwarded";
- case GNUNET_NAT_PORT_ERROR:
- return "Redirection failed";
- default:
- return "not found";
- }
+ struct LocalAddressList *pos;
+ struct LocalAddressList *next;
+
+ next = h->lal_head;
+ while (NULL != (pos = next))
+ {
+ next = pos->next;
+ if (pos->source != src)
+ continue;
+ GNUNET_CONTAINER_DLL_remove (h->lal_head, h->lal_tail, pos);
+ if (NULL != h->address_callback)
+ h->address_callback (h->callback_cls, GNUNET_NO,
+ (const struct sockaddr *) &pos[1], pos->addrlen);
+ GNUNET_free (pos);
+ }
}
-#endif
-static int
-get_traversal_status (const struct GNUNET_NAT_Handle * s)
+/**
+ * Add the given address to the list of 'local' addresses, thereby
+ * making it a 'legal' address for this peer to have.
+ *
+ * @param h handle to NAT
+ * @param src where did the local address originate from?
+ * @param arg the address, some 'struct sockaddr'
+ * @param arg_size number of bytes in arg
+ */
+static void
+add_to_address_list_as_is (struct GNUNET_NAT_Handle *h,
+ enum LocalAddressSource src,
+ const struct sockaddr *arg, socklen_t arg_size)
{
- return MAX (s->natpmp_status, s->upnp_status);
+ struct LocalAddressList *lal;
+
+ lal = GNUNET_malloc (sizeof (struct LocalAddressList) + arg_size);
+ memcpy (&lal[1], arg, arg_size);
+ lal->addrlen = arg_size;
+ lal->source = src;
+ GNUNET_CONTAINER_DLL_insert (h->lal_head, h->lal_tail, lal);
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "Adding address `%s' from source %d\n",
+ GNUNET_a2s (arg, arg_size), src);
+ if (NULL != h->address_callback)
+ h->address_callback (h->callback_cls, GNUNET_YES, arg, arg_size);
}
/**
- * Compare the sin(6)_addr fields of AF_INET or AF_INET(6) sockaddr.
- * @param a first sockaddr
- * @param b second sockaddr
- * @return 0 if addresses are equal, non-null value otherwise */
-int
-GNUNET_NAT_cmp_addr (const struct sockaddr *a,
- const struct sockaddr *b)
+ * Add the given address to the list of 'local' addresses, thereby
+ * making it a 'legal' address for this peer to have. Set the
+ * port number in the process to the advertised port and possibly
+ * also to zero (if we have the gnunet-helper-nat-server).
+ *
+ * @param h handle to NAT
+ * @param src where did the local address originate from?
+ * @param arg the address, some 'struct sockaddr'
+ * @param arg_size number of bytes in arg
+ */
+static void
+add_to_address_list (struct GNUNET_NAT_Handle *h, enum LocalAddressSource src,
+ const struct sockaddr *arg, socklen_t arg_size)
{
- if (!(a && b))
- return -1;
- if ( (a->sa_family == AF_INET) && (b->sa_family == AF_INET) )
- return memcmp (&(((struct sockaddr_in *) a)->sin_addr),
- &(((struct sockaddr_in *) b)->sin_addr),
- sizeof (struct in_addr));
- if ( (a->sa_family == AF_INET6) && (b->sa_family == AF_INET6) )
- return memcmp (&(((struct sockaddr_in6 *) a)->sin6_addr),
- &(((struct sockaddr_in6 *) b)->sin6_addr),
- sizeof (struct in6_addr));
- return -1;
+ struct sockaddr_in s4;
+ const struct sockaddr_in *in4;
+ struct sockaddr_in6 s6;
+ const struct sockaddr_in6 *in6;
+
+ if (arg_size == sizeof (struct sockaddr_in))
+ {
+ in4 = (const struct sockaddr_in *) arg;
+ s4 = *in4;
+ s4.sin_port = htons (h->adv_port);
+ add_to_address_list_as_is (h, src, (const struct sockaddr *) &s4,
+ sizeof (struct sockaddr_in));
+ if (GNUNET_YES == h->enable_nat_server)
+ {
+ /* also add with PORT = 0 to indicate NAT server is enabled */
+ s4.sin_port = htons (0);
+ add_to_address_list_as_is (h, src, (const struct sockaddr *) &s4,
+ sizeof (struct sockaddr_in));
+ }
+ }
+ else if (arg_size == sizeof (struct sockaddr_in6))
+ {
+ if (GNUNET_YES != h->disable_ipv6)
+ {
+ in6 = (const struct sockaddr_in6 *) arg;
+ s6 = *in6;
+ s6.sin6_port = htons (h->adv_port);
+ add_to_address_list_as_is (h, src, (const struct sockaddr *) &s6,
+ sizeof (struct sockaddr_in6));
+ }
+ }
+ else
+ {
+ GNUNET_assert (0);
+ }
}
/**
- * Deal with a new IP address or port redirection:
- * Send signals with the appropriate sockaddr (IP and port), free and changes
- * or nullify the previous sockaddr. Change the port if needed.
+ * Add the given IP address to the list of 'local' addresses, thereby
+ * making it a 'legal' address for this peer to have.
+ *
+ * @param h handle to NAT
+ * @param src where did the local address originate from?
+ * @param addr the address, some 'struct in_addr' or 'struct in6_addr'
+ * @param addrlen number of bytes in addr
*/
static void
-notify_change (struct GNUNET_NAT_Handle *nat,
- struct sockaddr *addr,
- size_t addrlen,
- int new_port_mapped)
+add_ip_to_address_list (struct GNUNET_NAT_Handle *h,
+ enum LocalAddressSource src, const void *addr,
+ socklen_t addrlen)
{
- if (new_port_mapped == nat->port_mapped)
- return;
- nat->port_mapped = new_port_mapped;
-
- if ( (NULL != nat->contact_addr) &&
- (NULL != nat->callback) )
- nat->callback (nat->callback_cls,
- GNUNET_NO,
- nat->contact_addr,
- sizeof (nat->contact_addr));
- GNUNET_free_non_null (nat->contact_addr);
- nat->contact_addr = NULL;
- GNUNET_free_non_null (nat->ext_addr);
- nat->ext_addr = NULL;
- if (NULL == addr)
- return;
- nat->ext_addr = GNUNET_malloc (addrlen);
- memcpy (nat->ext_addr, addr, addrlen);
-
- /* Recreate the ext_addr:public_port bogus address to pass to the callback */
- if (nat->ext_addr->sa_family == AF_INET)
- {
- struct sockaddr_in tmp_addr;
+ struct sockaddr_in s4;
+ const struct in_addr *in4;
+ struct sockaddr_in6 s6;
+ const struct in6_addr *in6;
- tmp_addr = GNUNET_malloc (sizeof (struct sockaddr_in));
- tmp_addr->sin_family = AF_INET;
-#ifdef HAVE_SOCKADDR_IN_SIN_LEN
- tmp_addr->sin_len = sizeof (struct sockaddr_in);
+ if (addrlen == sizeof (struct in_addr))
+ {
+ in4 = (const struct in_addr *) addr;
+ memset (&s4, 0, sizeof (s4));
+ s4.sin_family = AF_INET;
+ s4.sin_port = 0;
+#if HAVE_SOCKADDR_IN_SIN_LEN
+ s4.sin_len = (u_char) sizeof (struct sockaddr_in);
#endif
- tmp_addr->sin_port = port_mapped ? htons (nat->public_port) : 0;
- tmp_addr->sin_addr = ((struct sockaddr_in *) nat->ext_addr)->sin_addr;
- nat->contact_addr = (struct sockaddr *) tmp_addr;
- if (NULL != nat->callback)
- nat->callback (nat->callback_cls,
- GNUNET_YES,
- nat->contact_addr,
- sizeof (struct sockaddr_in));
- }
- else if (nat->ext_addr->sa_family == AF_INET6)
+ s4.sin_addr = *in4;
+ add_to_address_list (h, src, (const struct sockaddr *) &s4,
+ sizeof (struct sockaddr_in));
+ if (GNUNET_YES == h->enable_nat_server)
{
- struct sockaddr_in6 *tmp_addr;
+ /* also add with PORT = 0 to indicate NAT server is enabled */
+ s4.sin_port = htons (0);
+ add_to_address_list (h, src, (const struct sockaddr *) &s4,
+ sizeof (struct sockaddr_in));
- tmp_addr = GNUNET_malloc (sizeof (struct sockaddr_in6));
- tmp_addr->sin6_family = AF_INET6;
-#ifdef HAVE_SOCKADDR_IN_SIN_LEN
- tmp_addr->sin6_len = sizeof (struct sockaddr_in6);
+ }
+ }
+ else if (addrlen == sizeof (struct in6_addr))
+ {
+ if (GNUNET_YES != h->disable_ipv6)
+ {
+ in6 = (const struct in6_addr *) addr;
+ memset (&s6, 0, sizeof (s6));
+ s6.sin6_family = AF_INET6;
+ s6.sin6_port = htons (h->adv_port);
+#if HAVE_SOCKADDR_IN_SIN_LEN
+ s6.sin6_len = (u_char) sizeof (struct sockaddr_in6);
#endif
- tmp_addr->sin6_port = port_mapped ? htons (nat->public_port) : 0;
- tmp_addr->sin6_addr = ((struct sockaddr_in6 *) nat->ext_addr)->sin6_addr;
- nat->contact_addr = (struct sockaddr *) tmp_addr;
- if (NULL != nat->callback)
- nat->callback (nat->callback_cls,
- GNUNET_YES,
- nat->contact_addr,
- sizeof (struct sockaddr_in6));
+ s6.sin6_addr = *in6;
+ add_to_address_list (h, src, (const struct sockaddr *) &s6,
+ sizeof (struct sockaddr_in6));
}
+ }
else
+ {
+ GNUNET_assert (0);
+ }
+}
+
+
+/**
+ * Task to do DNS lookup on our external hostname to
+ * get DynDNS-IP addresses.
+ *
+ * @param cls the NAT handle
+ * @param tc scheduler context
+ */
+static void
+resolve_dns (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+
+/**
+ * Our (external) hostname was resolved and the configuration says that
+ * the NAT was hole-punched.
+ *
+ * @param cls the 'struct Plugin'
+ * @param addr NULL on error, otherwise result of DNS lookup
+ * @param addrlen number of bytes in addr
+ */
+static void
+process_external_ip (void *cls, const struct sockaddr *addr, socklen_t addrlen)
+{
+ struct GNUNET_NAT_Handle *h = cls;
+ struct in_addr dummy;
+
+ if (addr == NULL)
+ {
+ h->ext_dns = NULL;
+ if (1 == inet_pton (AF_INET, h->external_address, &dummy))
+ return; /* repated lookup pointless: was numeric! */
+ h->dns_task =
+ GNUNET_SCHEDULER_add_delayed (h->dyndns_frequency, &resolve_dns, h);
+ return;
+ }
+ add_to_address_list (h, LAL_EXTERNAL_IP, addr, addrlen);
+}
+
+
+/**
+ * Task to do a lookup on our hostname for IP addresses.
+ *
+ * @param cls the NAT handle
+ * @param tc scheduler context
+ */
+static void
+resolve_hostname (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+
+/**
+ * Function called by the resolver for each address obtained from DNS
+ * for our own hostname. Add the addresses to the list of our IP
+ * addresses.
+ *
+ * @param cls closure
+ * @param addr one of the addresses of the host, NULL for the last address
+ * @param addrlen length of the address
+ */
+static void
+process_hostname_ip (void *cls, const struct sockaddr *addr, socklen_t addrlen)
+{
+ struct GNUNET_NAT_Handle *h = cls;
+
+ if (addr == NULL)
+ {
+ h->hostname_dns = NULL;
+ h->hostname_task =
+ GNUNET_SCHEDULER_add_delayed (h->hostname_dns_frequency,
+ &resolve_hostname, h);
+ return;
+ }
+ add_to_address_list (h, LAL_HOSTNAME_DNS, addr, addrlen);
+}
+
+
+/**
+ * Add the IP of our network interface to the list of
+ * our IP addresses.
+ *
+ * @param cls the 'struct GNUNET_NAT_Handle'
+ * @param name name of the interface
+ * @param isDefault do we think this may be our default interface
+ * @param addr address of the interface
+ * @param broadcast_addr the broadcast address (can be NULL for unknown or unassigned)
+ * @param netmask the network mask (can be NULL for unknown or unassigned))
+ * @param addrlen number of bytes in addr
+ * @return GNUNET_OK to continue iterating
+ */
+static int
+process_interfaces (void *cls, const char *name, int isDefault,
+ const struct sockaddr *addr,
+ const struct sockaddr *broadcast_addr,
+ const struct sockaddr *netmask, socklen_t addrlen)
+{
+ struct GNUNET_NAT_Handle *h = cls;
+ const struct sockaddr_in *s4;
+ const struct sockaddr_in6 *s6;
+ const void *ip;
+ char buf[INET6_ADDRSTRLEN];
+
+ switch (addr->sa_family)
+ {
+ case AF_INET:
+ s4 = (struct sockaddr_in *) addr;
+ ip = &s4->sin_addr;
+
+ /* Check if address is in 127.0.0.0/8 */
+ uint32_t address = ntohl ((uint32_t) (s4->sin_addr.s_addr));
+ uint32_t value = (address & 0xFF000000) ^ 0x7F000000;
+
+ if ((h->return_localaddress == GNUNET_NO) && (value == 0))
+ {
+ return GNUNET_OK;
+ }
+ if (GNUNET_YES == h->use_localaddresses)
+ {
+ add_ip_to_address_list (h, LAL_INTERFACE_ADDRESS, &s4->sin_addr,
+ sizeof (struct in_addr));
+ }
+ break;
+ case AF_INET6:
+ s6 = (struct sockaddr_in6 *) addr;
+ if (IN6_IS_ADDR_LINKLOCAL (&((struct sockaddr_in6 *) addr)->sin6_addr))
+ {
+ /* skip link local addresses */
+ return GNUNET_OK;
+ }
+ if ((h->return_localaddress == GNUNET_NO) &&
+ (IN6_IS_ADDR_LOOPBACK (&((struct sockaddr_in6 *) addr)->sin6_addr)))
{
- GNUNET_break (0);
+ return GNUNET_OK;
}
+ ip = &s6->sin6_addr;
+ if (GNUNET_YES == h->use_localaddresses)
+ {
+ add_ip_to_address_list (h, LAL_INTERFACE_ADDRESS, &s6->sin6_addr,
+ sizeof (struct in6_addr));
+ }
+ break;
+ default:
+ GNUNET_break (0);
+ return GNUNET_OK;
+ }
+ if ((h->internal_address == NULL) && (h->server_proc == NULL) &&
+ (h->server_read_task == GNUNET_SCHEDULER_NO_TASK) &&
+ (GNUNET_YES == isDefault) && ((addr->sa_family == AF_INET) ||
+ (addr->sa_family == AF_INET6)))
+ {
+ /* no internal address configured, but we found a "default"
+ * interface, try using that as our 'internal' address */
+ h->internal_address =
+ GNUNET_strdup (inet_ntop (addr->sa_family, ip, buf, sizeof (buf)));
+ start_gnunet_nat_server (h);
+ }
+ return GNUNET_OK;
}
+/**
+ * Task that restarts the gnunet-helper-nat-server process after a crash
+ * after a certain delay.
+ *
+ * @param cls the 'struct GNUNET_NAT_Handle'
+ * @param tc scheduler context
+ */
static void
-nat_pulse (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+restart_nat_server (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
{
- struct GNUNET_NAT_Handle *nat = cls;
- int old_status;
- int new_status;
- int port_mapped;
- struct sockaddr *ext_addr_upnp = NULL;
- struct sockaddr *ext_addr_natpmp = NULL;
-
- nat->pulse_timer = GNUNET_SCHEDULER_NO_TASK;
- old_status = get_traversal_status (nat);
-
- /* Only update the protocol that has been successful until now */
- if (nat->upnp_status >= GNUNET_NAT_PORT_UNMAPPED)
- nat->upnp_status =
- GNUNET_NAT_UPNP_pulse (nat->upnp, nat->is_enabled, GNUNET_YES,
- &ext_addr_upnp);
- else if (nat->natpmp_status >= GNUNET_NAT_PORT_UNMAPPED)
- nat->natpmp_status =
- GNUNET_NAT_NATPMP_pulse (nat->natpmp, nat->is_enabled,
- &ext_addr_natpmp);
- else
+ struct GNUNET_NAT_Handle *h = cls;
+
+ h->server_read_task = GNUNET_SCHEDULER_NO_TASK;
+ if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
+ return;
+ start_gnunet_nat_server (h);
+}
+
+
+/**
+ * We have been notified that gnunet-helper-nat-server has written something to stdout.
+ * Handle the output, then reschedule this function to be called again once
+ * more is available.
+ *
+ * @param cls the NAT handle
+ * @param tc the scheduling context
+ */
+static void
+nat_server_read (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_NAT_Handle *h = cls;
+ char mybuf[40];
+ ssize_t bytes;
+ size_t i;
+ int port;
+ const char *port_start;
+ struct sockaddr_in sin_addr;
+
+ h->server_read_task = GNUNET_SCHEDULER_NO_TASK;
+ if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
+ return;
+ memset (mybuf, 0, sizeof (mybuf));
+ bytes =
+ GNUNET_DISK_file_read (h->server_stdout_handle, mybuf, sizeof (mybuf));
+ if (bytes < 1)
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Finished reading from server stdout with code: %d\n", bytes);
+ if (0 != GNUNET_OS_process_kill (h->server_proc, SIGTERM))
+ GNUNET_log_from_strerror (GNUNET_ERROR_TYPE_WARNING, "nat", "kill");
+ GNUNET_OS_process_wait (h->server_proc);
+ GNUNET_OS_process_destroy (h->server_proc);
+ h->server_proc = NULL;
+ GNUNET_DISK_pipe_close (h->server_stdout);
+ h->server_stdout = NULL;
+ h->server_stdout_handle = NULL;
+ /* now try to restart it */
+ h->server_retry_delay = GNUNET_TIME_STD_BACKOFF (h->server_retry_delay);
+ h->server_read_task =
+ GNUNET_SCHEDULER_add_delayed (h->server_retry_delay,
+ &restart_nat_server, h);
+ return;
+ }
+
+ port_start = NULL;
+ for (i = 0; i < sizeof (mybuf); i++)
+ {
+ if (mybuf[i] == '\n')
{
- /* try both */
- nat->upnp_status =
- GNUNET_NAT_UPNP_pulse (nat->upnp, nat->is_enabled, GNUNET_YES,
- &ext_addr_upnp);
- nat->natpmp_status =
- GNUNET_NAT_NATPMP_pulse (nat->natpmp, nat->is_enabled,
- &ext_addr_natpmp);
+ mybuf[i] = '\0';
+ break;
}
- new_status = get_traversal_status (nat);
- if ( (old_status != new_status) &&
- ( (new_status == GNUNET_NAT_PORT_UNMAPPED) ||
- (new_status == GNUNET_NAT_PORT_ERROR) ) )
- GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
- "NAT",
- _("Port redirection failed: no UPnP or NAT-PMP routers supporting this feature found\n"));
-#ifdef DEBUG
- if (new_status != old_status)
- GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "NAT",
- _("State changed from `%s' to `%s'\n"),
- get_nat_state_str (old_status),
- get_nat_state_str (new_status));
+ if ((mybuf[i] == ':') && (i + 1 < sizeof (mybuf)))
+ {
+ mybuf[i] = '\0';
+ port_start = &mybuf[i + 1];
+ }
+ }
+
+ /* construct socket address of sender */
+ memset (&sin_addr, 0, sizeof (sin_addr));
+ sin_addr.sin_family = AF_INET;
+#if HAVE_SOCKADDR_IN_SIN_LEN
+ sin_addr.sin_len = sizeof (sin_addr);
#endif
+ if ((NULL == port_start) || (1 != SSCANF (port_start, "%d", &port)) ||
+ (-1 == inet_pton (AF_INET, mybuf, &sin_addr.sin_addr)))
+ {
+ /* should we restart gnunet-helper-nat-server? */
+ LOG (GNUNET_ERROR_TYPE_WARNING, "nat",
+ _("gnunet-helper-nat-server generated malformed address `%s'\n"),
+ mybuf);
+ h->server_read_task =
+ GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
+ h->server_stdout_handle,
+ &nat_server_read, h);
+ return;
+ }
+ sin_addr.sin_port = htons ((uint16_t) port);
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "gnunet-helper-nat-server read: %s:%d\n", mybuf,
+ port);
+ h->reversal_callback (h->callback_cls, (const struct sockaddr *) &sin_addr,
+ sizeof (sin_addr));
+ h->server_read_task =
+ GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
+ h->server_stdout_handle, &nat_server_read,
+ h);
+}
+
- port_mapped = (new_status == GNUNET_NAT_PORT_MAPPED);
- if (!(ext_addr_upnp || ext_addr_natpmp))
+/**
+ * Try to start the gnunet-helper-nat-server (if it is not
+ * already running).
+ *
+ * @param h handle to NAT
+ */
+static void
+start_gnunet_nat_server (struct GNUNET_NAT_Handle *h)
+{
+ char *binary;
+
+ if ((h->behind_nat == GNUNET_YES) && (h->enable_nat_server == GNUNET_YES) &&
+ (h->internal_address != NULL) &&
+ (NULL !=
+ (h->server_stdout =
+ GNUNET_DISK_pipe (GNUNET_YES, GNUNET_YES, GNUNET_NO, GNUNET_YES))))
+ {
+ LOG (GNUNET_ERROR_TYPE_DEBUG, "Starting `%s' at `%s'\n",
+ "gnunet-helper-nat-server", h->internal_address);
+ /* Start the server process */
+ binary = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-server");
+ h->server_proc =
+ GNUNET_OS_start_process (GNUNET_NO, 0, NULL, h->server_stdout,
+ binary,
+ "gnunet-helper-nat-server",
+ h->internal_address, NULL);
+ GNUNET_free (binary);
+ if (h->server_proc == NULL)
{
- /* Address has just changed and we could not get it, or it's the first try */
- if ( (NULL != nat->ext_addr) ||
- (GNUNET_NO == nat->did_warn) )
- {
- GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
- "NAT",
- _("Could not determine external IP address\n"));
- nat->did_warn = GNUNET_YES;
- }
- notify_change (nat, NULL, port_mapped);
+ LOG (GNUNET_ERROR_TYPE_WARNING, "nat", _("Failed to start %s\n"),
+ "gnunet-helper-nat-server");
+ GNUNET_DISK_pipe_close (h->server_stdout);
+ h->server_stdout = NULL;
}
- else if (ext_addr_upnp && GNUNET_NAT_cmp_addr (nat->ext_addr, ext_addr_upnp) != 0)
+ else
{
- GNUNET_log_from (GNUNET_ERROR_TYPE_INFO,
- "NAT",
- _("External IP address changed to %s\n"),
- GNUNET_a2s (ext_addr_upnp, sizeof (ext_addr_upnp)));
- notify_change (nat, ext_addr_upnp, port_mapped);
+ /* Close the write end of the read pipe */
+ GNUNET_DISK_pipe_close_end (h->server_stdout, GNUNET_DISK_PIPE_END_WRITE);
+ h->server_stdout_handle =
+ GNUNET_DISK_pipe_handle (h->server_stdout, GNUNET_DISK_PIPE_END_READ);
+ h->server_read_task =
+ GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
+ h->server_stdout_handle,
+ &nat_server_read, h);
}
- else if (ext_addr_natpmp && GNUNET_NAT_cmp_addr (nat->ext_addr, ext_addr_natpmp) != 0)
+ }
+}
+
+
+/**
+ * Task to scan the local network interfaces for IP addresses.
+ *
+ * @param cls the NAT handle
+ * @param tc scheduler context
+ */
+static void
+list_interfaces (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_NAT_Handle *h = cls;
+
+ h->ifc_task = GNUNET_SCHEDULER_NO_TASK;
+ remove_from_address_list_by_source (h, LAL_INTERFACE_ADDRESS);
+ GNUNET_OS_network_interfaces_list (&process_interfaces, h);
+ h->ifc_task =
+ GNUNET_SCHEDULER_add_delayed (h->ifc_scan_frequency, &list_interfaces, h);
+}
+
+
+/**
+ * Task to do a lookup on our hostname for IP addresses.
+ *
+ * @param cls the NAT handle
+ * @param tc scheduler context
+ */
+static void
+resolve_hostname (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_NAT_Handle *h = cls;
+
+ h->hostname_task = GNUNET_SCHEDULER_NO_TASK;
+ remove_from_address_list_by_source (h, LAL_HOSTNAME_DNS);
+ h->hostname_dns =
+ GNUNET_RESOLVER_hostname_resolve (AF_UNSPEC, HOSTNAME_RESOLVE_TIMEOUT,
+ &process_hostname_ip, h);
+}
+
+
+/**
+ * Task to do DNS lookup on our external hostname to
+ * get DynDNS-IP addresses.
+ *
+ * @param cls the NAT handle
+ * @param tc scheduler context
+ */
+static void
+resolve_dns (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_NAT_Handle *h = cls;
+
+ h->dns_task = GNUNET_SCHEDULER_NO_TASK;
+ remove_from_address_list_by_source (h, LAL_EXTERNAL_IP);
+ h->ext_dns =
+ GNUNET_RESOLVER_ip_get (h->external_address, AF_INET,
+ GNUNET_TIME_UNIT_MINUTES, &process_external_ip,
+ h);
+}
+
+
+/**
+ * Add or remove UPnP-mapped addresses.
+ *
+ * @param cls the GNUNET_NAT_Handle
+ * @param add_remove GNUNET_YES to mean the new public IP address, GNUNET_NO to mean
+ * the previous (now invalid) one
+ * @param addr either the previous or the new public IP address
+ * @param addrlen actual lenght of the address
+ */
+static void
+upnp_add (void *cls, int add_remove, const struct sockaddr *addr,
+ socklen_t addrlen)
+{
+ struct GNUNET_NAT_Handle *h = cls;
+ struct LocalAddressList *pos;
+ struct LocalAddressList *next;
+
+ if (GNUNET_YES == add_remove)
+ {
+ add_to_address_list (h, LAL_UPNP, addr, addrlen);
+ return;
+ }
+ /* remove address */
+ next = h->lal_head;
+ while (NULL != (pos = next))
+ {
+ next = pos->next;
+ if ((pos->source != LAL_UPNP) || (pos->addrlen != addrlen) ||
+ (0 != memcmp (&pos[1], addr, addrlen)))
+ continue;
+ GNUNET_CONTAINER_DLL_remove (h->lal_head, h->lal_tail, pos);
+ if (NULL != h->address_callback)
+ h->address_callback (h->callback_cls, GNUNET_NO,
+ (const struct sockaddr *) &pos[1], pos->addrlen);
+ GNUNET_free (pos);
+ return; /* only remove once */
+ }
+ /* asked to remove address that does not exist */
+ GNUNET_break (0);
+}
+
+
+/**
+ * Try to add a port mapping using UPnP.
+ *
+ * @param h overall NAT handle
+ * @param port port to map with UPnP
+ */
+static void
+add_minis (struct GNUNET_NAT_Handle *h, uint16_t port)
+{
+ struct MiniList *ml;
+
+ ml = h->mini_head;
+ while (NULL != ml)
+ {
+ if (port == ml->port)
+ return; /* already got this port */
+ ml = ml->next;
+ }
+ ml = GNUNET_malloc (sizeof (struct MiniList));
+ ml->port = port;
+ ml->mini = GNUNET_NAT_mini_map_start (port, h->is_tcp, &upnp_add, h);
+ GNUNET_CONTAINER_DLL_insert (h->mini_head, h->mini_tail, ml);
+}
+
+
+/**
+ * Task to add addresses from original bind to set of valid addrs.
+ *
+ * @param cls the NAT handle
+ * @param tc scheduler context
+ */
+static void
+add_from_bind (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ static struct in6_addr any = IN6ADDR_ANY_INIT;
+ struct GNUNET_NAT_Handle *h = cls;
+ unsigned int i;
+ struct sockaddr *sa;
+ const struct sockaddr_in *v4;
+
+ h->bind_task = GNUNET_SCHEDULER_NO_TASK;
+ for (i = 0; i < h->num_local_addrs; i++)
+ {
+ sa = h->local_addrs[i];
+ switch (sa->sa_family)
{
- GNUNET_log_from (GNUNET_ERROR_TYPE_INFO, "NAT",
- _("External IP address changed to `%s'\n"),
- GNUNET_a2s (ext_addr_natpmp, sizeof (ext_addr_natpmp)));
- notify_change (nat, ext_addr_natpmp, port_mapped);
+ case AF_INET:
+ if (sizeof (struct sockaddr_in) != h->local_addrlens[i])
+ {
+ GNUNET_break (0);
+ break;
+ }
+ v4 = (const struct sockaddr_in *) sa;
+ if (0 != v4->sin_addr.s_addr)
+ add_to_address_list (h, LAL_BINDTO_ADDRESS, sa,
+ sizeof (struct sockaddr_in));
+ if (h->enable_upnp)
+ add_minis (h, ntohs (v4->sin_port));
+ break;
+ case AF_INET6:
+ if (sizeof (struct sockaddr_in6) != h->local_addrlens[i])
+ {
+ GNUNET_break (0);
+ break;
+ }
+ if (0 !=
+ memcmp (&((const struct sockaddr_in6 *) sa)->sin6_addr, &any,
+ sizeof (struct in6_addr)))
+ add_to_address_list (h, LAL_BINDTO_ADDRESS, sa,
+ sizeof (struct sockaddr_in6));
+ break;
+ default:
+ break;
}
- nat->pulse_timer = GNUNET_SCHEDULER_add_delayed (nat->sched,
- GNUNET_TIME_UNIT_SECONDS,
- &nat_pulse, nat);
+ }
}
+
/**
* Attempt to enable port redirection and detect public IP address contacting
* UPnP or NAT-PMP routers on the local network. Use addr to specify to which
* of the local host's addresses should the external port be mapped. The port
* is taken from the corresponding sockaddr_in[6] field.
*
- * @param sched the sheduler used in the program
- * @param addr the local address packets should be redirected to
- * @param addrlen actual lenght of the address
- * @param callback function to call everytime the public IP address changes
- * @param callback_cls closure for callback
- * @return NULL on error, otherwise handle that can be used to unregister
+ * @param cfg configuration to use
+ * @param is_tcp GNUNET_YES for TCP, GNUNET_NO for UDP
+ * @param adv_port advertised port (port we are either bound to or that our OS
+ * locally performs redirection from to our bound port).
+ * @param num_addrs number of addresses in 'addrs'
+ * @param addrs the local addresses packets should be redirected to
+ * @param addrlens actual lengths of the addresses
+ * @param address_callback function to call everytime the public IP address changes
+ * @param reversal_callback function to call if someone wants connection reversal from us
+ * @param callback_cls closure for callbacks
+ * @return NULL on error, otherwise handle that can be used to unregister
*/
struct GNUNET_NAT_Handle *
-GNUNET_NAT_register (struct GNUNET_SCHEDULER_Handle *sched,
- const struct sockaddr *addr, socklen_t addrlen,
- GNUNET_NAT_AddressCallback callback, void *callback_cls)
+GNUNET_NAT_register (const struct GNUNET_CONFIGURATION_Handle *cfg, int is_tcp,
+ uint16_t adv_port, unsigned int num_addrs,
+ const struct sockaddr **addrs, const socklen_t * addrlens,
+ GNUNET_NAT_AddressCallback address_callback,
+ GNUNET_NAT_ReversalCallback reversal_callback,
+ void *callback_cls)
{
- struct GNUNET_NAT_Handle *nat;
+ struct GNUNET_NAT_Handle *h;
+ struct in_addr in_addr;
+ unsigned int i;
+ char *binary;
- nat = GNUNET_malloc (sizeof (struct GNUNET_NAT_Handle));
- if (addr)
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Registered with NAT service at port %u with %u IP bound local addresses\n",
+ (unsigned int) adv_port, num_addrs);
+ h = GNUNET_malloc (sizeof (struct GNUNET_NAT_Handle));
+ h->server_retry_delay = GNUNET_TIME_UNIT_SECONDS;
+ h->cfg = cfg;
+ h->is_tcp = is_tcp;
+ h->address_callback = address_callback;
+ h->reversal_callback = reversal_callback;
+ h->callback_cls = callback_cls;
+ h->num_local_addrs = num_addrs;
+ h->adv_port = adv_port;
+ if (num_addrs != 0)
+ {
+ h->local_addrs = GNUNET_malloc (num_addrs * sizeof (struct sockaddr *));
+ h->local_addrlens = GNUNET_malloc (num_addrs * sizeof (socklen_t));
+ for (i = 0; i < num_addrs; i++)
{
- GNUNET_assert ( (addr->sa_family == AF_INET) ||
- (addr->sa_family == AF_INET6) );
- nat->local_addr = GNUNET_malloc (addrlen);
- memcpy (nat->local_addr, addr, addrlen);
- if (addr->sa_family == AF_INET)
- {
- nat->public_port = ntohs (((struct sockaddr_in *) addr)->sin_port);
- ((struct sockaddr_in *) nat->local_addr)->sin_port = 0;
- }
- else if (addr->sa_family == AF_INET6)
- {
- nat->public_port = ntohs (((struct sockaddr_in6 *) addr)->sin6_port);
- ((struct sockaddr_in6 *) nat->local_addr)->sin6_port = 0;
- }
+ GNUNET_assert (addrlens[i] > 0);
+ GNUNET_assert (addrs[i] != NULL);
+ h->local_addrlens[i] = addrlens[i];
+ h->local_addrs[i] = GNUNET_malloc (addrlens[i]);
+ memcpy (h->local_addrs[i], addrs[i], addrlens[i]);
}
- nat->should_change = GNUNET_YES;
- nat->sched = sched;
- nat->is_enabled = GNUNET_YES;
- nat->upnp_status = GNUNET_NAT_PORT_UNMAPPED;
- nat->natpmp_status = GNUNET_NAT_PORT_UNMAPPED;
- nat->callback = callback;
- nat->callback_cls = callback_cls;
- nat->natpmp = GNUNET_NAT_NATPMP_init (nat->local_addr, addrlen, nat->public_port);
- nat->upnp = GNUNET_NAT_UPNP_init (nat->local_addr, addrlen, nat->public_port);
- nat->pulse_timer = GNUNET_SCHEDULER_add_delayed (sched,
- GNUNET_TIME_UNIT_SECONDS,
- &nat_pulse, nat);
- return nat;
+ }
+ h->bind_task = GNUNET_SCHEDULER_add_now (&add_from_bind, h);
+ if (GNUNET_OK ==
+ GNUNET_CONFIGURATION_have_value (cfg, "nat", "INTERNAL_ADDRESS"))
+ {
+ (void) GNUNET_CONFIGURATION_get_value_string (cfg, "nat",
+ "INTERNAL_ADDRESS",
+ &h->internal_address);
+ }
+ if ((h->internal_address != NULL) &&
+ (inet_pton (AF_INET, h->internal_address, &in_addr) != 1))
+ {
+ GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING,
+ "nat", "INTERNAL_ADDRESS",
+ _("malformed"));
+ GNUNET_free (h->internal_address);
+ h->internal_address = NULL;
+ }
+
+ if (GNUNET_OK ==
+ GNUNET_CONFIGURATION_have_value (cfg, "nat", "EXTERNAL_ADDRESS"))
+ {
+ (void) GNUNET_CONFIGURATION_get_value_string (cfg, "nat",
+ "EXTERNAL_ADDRESS",
+ &h->external_address);
+ }
+ h->behind_nat =
+ GNUNET_CONFIGURATION_get_value_yesno (cfg, "nat", "BEHIND_NAT");
+ h->nat_punched =
+ GNUNET_CONFIGURATION_get_value_yesno (cfg, "nat", "PUNCHED_NAT");
+ h->enable_nat_client =
+ GNUNET_CONFIGURATION_get_value_yesno (cfg, "nat", "ENABLE_ICMP_CLIENT");
+ h->enable_nat_server =
+ GNUNET_CONFIGURATION_get_value_yesno (cfg, "nat", "ENABLE_ICMP_SERVER");
+ h->enable_upnp =
+ GNUNET_CONFIGURATION_get_value_yesno (cfg, "nat", "ENABLE_UPNP");
+ h->use_localaddresses =
+ GNUNET_CONFIGURATION_get_value_yesno (cfg, "nat", "USE_LOCALADDR");
+ h->return_localaddress =
+ GNUNET_CONFIGURATION_get_value_yesno (cfg, "nat",
+ "RETURN_LOCAL_ADDRESSES");
+
+ h->use_hostname =
+ GNUNET_CONFIGURATION_get_value_yesno (cfg, "nat", "USE_HOSTNAME");
+ h->disable_ipv6 =
+ GNUNET_CONFIGURATION_get_value_yesno (cfg, "nat", "DISABLEV6");
+ if (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_time (cfg, "nat", "DYNDNS_FREQUENCY",
+ &h->dyndns_frequency))
+ h->dyndns_frequency = DYNDNS_FREQUENCY;
+ if (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_time (cfg, "nat", "IFC_SCAN_FREQUENCY",
+ &h->ifc_scan_frequency))
+ h->ifc_scan_frequency = IFC_SCAN_FREQUENCY;
+ if (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_time (cfg, "nat", "HOSTNAME_DNS_FREQUENCY",
+ &h->hostname_dns_frequency))
+ h->hostname_dns_frequency = HOSTNAME_DNS_FREQUENCY;
+
+ if (NULL == reversal_callback)
+ h->enable_nat_server = GNUNET_NO;
+
+ /* Check if NAT was hole-punched */
+ if ((NULL != h->address_callback) && (h->external_address != NULL) &&
+ (h->nat_punched == GNUNET_YES))
+ {
+ h->dns_task = GNUNET_SCHEDULER_add_now (&resolve_dns, h);
+ h->enable_nat_server = GNUNET_NO;
+ h->enable_upnp = GNUNET_NO;
+ }
+
+ /* Test for SUID binaries */
+ binary = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-server");
+ if ((h->behind_nat == GNUNET_YES) && (GNUNET_YES == h->enable_nat_server) &&
+ (GNUNET_YES !=
+ GNUNET_OS_check_helper_binary (binary)))
+ {
+ h->enable_nat_server = GNUNET_NO;
+ LOG (GNUNET_ERROR_TYPE_WARNING,
+ _
+ ("Configuration requires `%s', but binary is not installed properly (SUID bit not set). Option disabled.\n"),
+ "gnunet-helper-nat-server");
+ }
+ GNUNET_free (binary);
+ binary = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-client");
+ if ((GNUNET_YES == h->enable_nat_client) &&
+ (GNUNET_YES !=
+ GNUNET_OS_check_helper_binary (binary)))
+ {
+ h->enable_nat_client = GNUNET_NO;
+ LOG (GNUNET_ERROR_TYPE_WARNING,
+ _
+ ("Configuration requires `%s', but binary is not installed properly (SUID bit not set). Option disabled.\n"),
+ "gnunet-helper-nat-client");
+ }
+ GNUNET_free (binary);
+ start_gnunet_nat_server (h);
+
+ /* FIXME: add support for UPnP, etc */
+
+ if (NULL != h->address_callback)
+ {
+ h->ifc_task = GNUNET_SCHEDULER_add_now (&list_interfaces, h);
+ if (GNUNET_YES == h->use_hostname)
+ h->hostname_task = GNUNET_SCHEDULER_add_now (&resolve_hostname, h);
+ }
+
+ return h;
}
void
GNUNET_NAT_unregister (struct GNUNET_NAT_Handle *h)
{
- struct sockaddr *addr;
-
- GNUNET_SCHEDULER_cancel (h->sched,
- h->pulse_timer);
- h->upnp_status =
- GNUNET_NAT_UPNP_pulse (h->upnp,
- GNUNET_NO, GNUNET_NO,
- &addr);
- h->natpmp_status =
- GNUNET_NAT_NATPMP_pulse (h->natpmp, GNUNET_NO,
- &addr);
- GNUNET_NAT_NATPMP_close (h->natpmp);
- GNUNET_NAT_UPNP_close (h->upnp);
- GNUNET_free_non_null (h->local_addr);
- GNUNET_free_non_null (h->ext_addr);
+ unsigned int i;
+ struct LocalAddressList *lal;
+ struct MiniList *ml;
+
+ while (NULL != (ml = h->mini_head))
+ {
+ GNUNET_CONTAINER_DLL_remove (h->mini_head, h->mini_tail, ml);
+ if (NULL != ml->mini)
+ GNUNET_NAT_mini_map_stop (ml->mini);
+ GNUNET_free (ml);
+ }
+ if (h->ext_dns != NULL)
+ {
+ GNUNET_RESOLVER_request_cancel (h->ext_dns);
+ h->ext_dns = NULL;
+ }
+ if (NULL != h->hostname_dns)
+ {
+ GNUNET_RESOLVER_request_cancel (h->hostname_dns);
+ h->hostname_dns = NULL;
+ }
+ if (GNUNET_SCHEDULER_NO_TASK != h->server_read_task)
+ {
+ GNUNET_SCHEDULER_cancel (h->server_read_task);
+ h->server_read_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ if (GNUNET_SCHEDULER_NO_TASK != h->bind_task)
+ {
+ GNUNET_SCHEDULER_cancel (h->bind_task);
+ h->bind_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ if (GNUNET_SCHEDULER_NO_TASK != h->ifc_task)
+ {
+ GNUNET_SCHEDULER_cancel (h->ifc_task);
+ h->ifc_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ if (GNUNET_SCHEDULER_NO_TASK != h->hostname_task)
+ {
+ GNUNET_SCHEDULER_cancel (h->hostname_task);
+ h->hostname_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ if (GNUNET_SCHEDULER_NO_TASK != h->dns_task)
+ {
+ GNUNET_SCHEDULER_cancel (h->dns_task);
+ h->dns_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ if (NULL != h->server_proc)
+ {
+ if (0 != GNUNET_OS_process_kill (h->server_proc, SIGTERM))
+ GNUNET_log_from_strerror (GNUNET_ERROR_TYPE_WARNING, "nat", "kill");
+ GNUNET_OS_process_wait (h->server_proc);
+ GNUNET_OS_process_destroy (h->server_proc);
+ h->server_proc = NULL;
+ GNUNET_DISK_pipe_close (h->server_stdout);
+ h->server_stdout = NULL;
+ h->server_stdout_handle = NULL;
+ }
+ if (NULL != h->server_stdout)
+ {
+ GNUNET_DISK_pipe_close (h->server_stdout);
+ h->server_stdout = NULL;
+ h->server_stdout_handle = NULL;
+ }
+ while (NULL != (lal = h->lal_head))
+ {
+ GNUNET_CONTAINER_DLL_remove (h->lal_head, h->lal_tail, lal);
+ if (NULL != h->address_callback)
+ h->address_callback (h->callback_cls, GNUNET_NO,
+ (const struct sockaddr *) &lal[1], lal->addrlen);
+ GNUNET_free (lal);
+ }
+ for (i = 0; i < h->num_local_addrs; i++)
+ GNUNET_free (h->local_addrs[i]);
+ GNUNET_free_non_null (h->local_addrs);
+ GNUNET_free_non_null (h->local_addrlens);
+ GNUNET_free_non_null (h->external_address);
+ GNUNET_free_non_null (h->internal_address);
GNUNET_free (h);
}
-/* end of nat.c */
+/**
+ * We learned about a peer (possibly behind NAT) so run the
+ * gnunet-helper-nat-client to send dummy ICMP responses to cause
+ * that peer to connect to us (connection reversal).
+ *
+ * @return GNUNET_SYSERR on error, GNUNET_NO if nat client is disabled,
+ * GNUNET_OK otherwise
+ */
+int
+GNUNET_NAT_run_client (struct GNUNET_NAT_Handle *h,
+ const struct sockaddr_in *sa)
+
+
+{
+ char inet4[INET_ADDRSTRLEN];
+ char port_as_string[6];
+ struct GNUNET_OS_Process *proc;
+ char *binary;
+
+ if (GNUNET_YES != h->enable_nat_client)
+ return GNUNET_NO; /* not permitted / possible */
+
+ if (h->internal_address == NULL)
+ {
+ LOG (GNUNET_ERROR_TYPE_WARNING, "nat",
+ _
+ ("Internal IP address not known, cannot use ICMP NAT traversal method\n"));
+ return GNUNET_SYSERR;
+ }
+ GNUNET_assert (sa->sin_family == AF_INET);
+ if (NULL == inet_ntop (AF_INET, &sa->sin_addr, inet4, INET_ADDRSTRLEN))
+ {
+ GNUNET_log_from_strerror (GNUNET_ERROR_TYPE_WARNING, "nat", "inet_ntop");
+ return GNUNET_SYSERR;
+ }
+ GNUNET_snprintf (port_as_string, sizeof (port_as_string), "%d", h->adv_port);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ _("Running gnunet-helper-nat-client %s %s %u\n"), h->internal_address,
+ inet4, (unsigned int) h->adv_port);
+ binary = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-client");
+ proc =
+ GNUNET_OS_start_process (GNUNET_NO, 0, NULL, NULL,
+ binary,
+ "gnunet-helper-nat-client", h->internal_address,
+ inet4, port_as_string, NULL);
+ GNUNET_free (binary);
+ if (NULL == proc)
+ return GNUNET_SYSERR;
+ /* we know that the gnunet-helper-nat-client will terminate virtually
+ * instantly */
+ GNUNET_OS_process_wait (proc);
+ GNUNET_OS_process_destroy (proc);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Test if the given address is (currently) a plausible IP address for this peer.
+ *
+ * @param h the handle returned by register
+ * @param addr IP address to test (IPv4 or IPv6)
+ * @param addrlen number of bytes in addr
+ * @return GNUNET_YES if the address is plausible,
+ * GNUNET_NO if the address is not plausible,
+ * GNUNET_SYSERR if the address is malformed
+ */
+int
+GNUNET_NAT_test_address (struct GNUNET_NAT_Handle *h, const void *addr,
+ socklen_t addrlen)
+{
+ struct LocalAddressList *pos;
+ const struct sockaddr_in *in4;
+ const struct sockaddr_in6 *in6;
+
+ if ((addrlen != sizeof (struct in_addr)) &&
+ (addrlen != sizeof (struct in6_addr)))
+ {
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+ pos = h->lal_head;
+ while (NULL != pos)
+ {
+ if (pos->addrlen == sizeof (struct sockaddr_in))
+ {
+ in4 = (struct sockaddr_in *) &pos[1];
+ if ((addrlen == sizeof (struct in_addr)) &&
+ (0 == memcmp (&in4->sin_addr, addr, sizeof (struct in_addr))))
+ return GNUNET_YES;
+ }
+ else if (pos->addrlen == sizeof (struct sockaddr_in6))
+ {
+ in6 = (struct sockaddr_in6 *) &pos[1];
+ if ((addrlen == sizeof (struct in6_addr)) &&
+ (0 == memcmp (&in6->sin6_addr, addr, sizeof (struct in6_addr))))
+ return GNUNET_YES;
+ }
+ else
+ {
+ GNUNET_assert (0);
+ }
+ pos = pos->next;
+ }
+ LOG (GNUNET_ERROR_TYPE_WARNING,
+ "Asked to validate one of my addresses and validation failed!\n");
+ return GNUNET_NO;
+}
+
+
+/* end of nat.c */