*/
#include "platform.h"
#include "gnunet-service-transport_validation.h"
+#include "gnunet-service-transport_plugins.h"
+#include "gnunet-service-transport_hello.h"
#include "gnunet-service-transport.h"
#include "gnunet_hello_lib.h"
#include "gnunet_peerinfo_service.h"
+#include "gnunet_signatures.h"
-/**
- * How long until a HELLO verification attempt should time out?
- * Must be rather small, otherwise a partially successful HELLO
- * validation (some addresses working) might not be available
- * before a client's request for a connection fails for good.
- * Besides, if a single request to an address takes a long time,
- * then the peer is unlikely worthwhile anyway.
- */
-#define HELLO_VERIFICATION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
/**
* How long is a PONG signature valid? We'll recycle a signature until
*/
#define HELLO_ADDRESS_EXPIRATION GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 12)
-
/**
* How long before an existing address expires should we again try to
* validate it? Must be (significantly) smaller than
*/
#define VALIDATION_MAP_SIZE 256
+/**
+ * Priority to use for PINGs
+ */
+#define PING_PRIORITY 2
+
+/**
+ * Priority to use for PONGs
+ */
+#define PONG_PRIORITY 4
+
+
+/**
+ * Message used to ask a peer to validate receipt (to check an address
+ * from a HELLO). Followed by the address we are trying to validate,
+ * or an empty address if we are just sending a PING to confirm that a
+ * connection which the receiver (of the PING) initiated is still valid.
+ */
+struct TransportPingMessage
+{
+
+ /**
+ * Type will be GNUNET_MESSAGE_TYPE_TRANSPORT_PING
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Challenge code (to ensure fresh reply).
+ */
+ uint32_t challenge GNUNET_PACKED;
+
+ /**
+ * Who is the intended recipient?
+ */
+ struct GNUNET_PeerIdentity target;
+
+};
+
+
+/**
+ * Message used to validate a HELLO. The challenge is included in the
+ * confirmation to make matching of replies to requests possible. The
+ * signature signs our public key, an expiration time and our address.<p>
+ *
+ * This message is followed by our transport address that the PING tried
+ * to confirm (if we liked it). The address can be empty (zero bytes)
+ * if the PING had not address either (and we received the request via
+ * a connection that we initiated).
+ */
+struct TransportPongMessage
+{
+
+ /**
+ * Type will be GNUNET_MESSAGE_TYPE_TRANSPORT_PONG
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Challenge code from PING (showing freshness). Not part of what
+ * is signed so that we can re-use signatures.
+ */
+ uint32_t challenge GNUNET_PACKED;
+
+ /**
+ * Signature.
+ */
+ struct GNUNET_CRYPTO_RsaSignature signature;
+
+ /**
+ * What are we signing and why? Two possible reason codes can be here:
+ * GNUNET_SIGNATURE_PURPOSE_TRANSPORT_PONG_OWN to confirm that this is a
+ * plausible address for this peer (pid is set to identity of signer); or
+ * GNUNET_SIGNATURE_PURPOSE_TRANSPORT_PONG_USING to confirm that this is
+ * an address we used to connect to the peer with the given pid.
+ */
+ struct GNUNET_CRYPTO_RsaSignaturePurpose purpose;
+
+ /**
+ * When does this signature expire?
+ */
+ struct GNUNET_TIME_AbsoluteNBO expiration;
+
+ /**
+ * Either the identity of the peer Who signed this message, or the
+ * identity of the peer that we're connected to using the given
+ * address (depending on purpose.type).
+ */
+ struct GNUNET_PeerIdentity pid;
+
+ /**
+ * Size of address appended to this message (part of what is
+ * being signed, hence not redundant).
+ */
+ uint32_t addrlen;
+
+};
+
/**
* Information about an address under validation
*/
const void *addr;
+ /**
+ * Public key of the peer.
+ */
+ struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded public_key;
+
/**
* The identity of the peer.
*/
struct GNUNET_TIME_Absolute send_time;
/**
- * When did we last succeed with validating this address?
- * FOREVER if the address has not been validated (we're currently checking)
- * ZERO if the address was validated a long time ago (from PEERINFO)
- * otherwise a time in the past if this process validated the address
+ * Until when is this address valid?
+ * ZERO if it is not currently considered valid.
*/
- struct GNUNET_TIME_Absolute last_validated_at;
+ struct GNUNET_TIME_Absolute valid_until;
/**
* How long until we can try to validate this address again?
*/
const struct GNUNET_HELLO_Message *hello;
- /**
- * Context for peerinfo iteration.
- */
- struct GNUNET_PEERINFO_IteratorContext *piter;
-
};
*/
static struct GNUNET_CONTAINER_MultiHashMap *notify_map;
-
-/**
- * Start the validation subsystem.
- */
-void
-GST_validation_start ()
-{
- validation_map = GNUNET_CONTAINER_multihashmap_create (VALIDATION_MAP_SIZE);
- notify_map = GNUNET_CONTAINER_multihashmap_create (VALIDATION_MAP_SIZE);
-}
-
-
-/**
- * Iterate over validation entries and free them.
- *
- * @param cls (unused)
- * @param key peer identity (unused)
- * @param value a 'struct ValidationEntry' to clean up
- * @return GNUNET_YES (continue to iterate)
- */
-static int
-cleanup_validation_entry (void *cls,
- const GNUNET_HashCode *key,
- void *value)
-{
- struct ValidationEntry *ve = value;
-
- GNUNET_free (ve->transport_name);
- if (GNUNET_SCHEDULER_NO_TASK != ve->timeout_task)
- {
- GNUNET_SCHEDULER_cancel (ve->timeout_task);
- ve->timeout_task = GNUNET_SCHEDULER_NO_TASK;
- }
- GNUNET_free (ve);
- return GNUNET_OK;
-}
-
-
-/**
- * Stop the validation subsystem.
- */
-void
-GST_validation_stop ()
-{
- struct CheckHelloValidatedContext *chvc;
-
- GNUNET_CONTAINER_multihashmap_iterate (validation_map,
- &cleanup_validation_entry,
- NULL);
- GNUNET_CONTAINER_multihashmap_destroy (validation_map);
- validation_map = NULL;
- GNUNET_assert (GNUNET_CONTAINER_multihashmap_size (notify_map) == 0);
- GNUNET_CONTAINER_multihashmap_destroy (notify_map);
- notify_map = NULL;
- while (NULL != (chvc = chvc_head))
- {
- GNUNET_CONTAINER_DLL_remove (chvc_head,
- chvc_tail,
- chvc);
- GNUNET_PEERINFO_iterate_cancel (chvc->piter);
- GNUNET_free (chvc);
- }
-}
-
-
-#if 0
/**
- * Address validation cleanup task (record no longer needed).
- *
- * @param cls the 'struct ValidationEntry'
- * @param tc scheduler context (unused)
+ * Context for peerinfo iteration.
*/
-static void
-timeout_hello_validation (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
-{
- struct ValidationEntry *va = cls;
-
- va->timeout_task = GNUNET_SCHEDULER_NO_TASK;
- GNUNET_STATISTICS_update (GST_stats,
- gettext_noop ("# address records discarded"),
- 1,
- GNUNET_NO);
- GNUNET_break (GNUNET_OK ==
- GNUNET_CONTAINER_multihashmap_remove (validation_map,
- &va->pid.hashPubKey,
- va));
- GNUNET_free (va->transport_name);
- GNUNET_free (va);
-}
-#endif
+static struct GNUNET_PEERINFO_NotifyContext *pnc;
/**
* the given address and transport. If none exists, create one (but
* without starting any validation).
*
+ * @param public_key public key of the peer, NULL for unknown
* @param neighbour which peer we care about
* @param tname name of the transport plugin
* @param session session to look for, NULL for 'any'; otherwise
* if 'addr' matches
* @param addr binary address
* @param addrlen length of addr
- * @return validation entry matching the given specifications
+ * @return validation entry matching the given specifications, NULL
+ * if we don't have an existing entry and no public key was given
*/
static struct ValidationEntry *
-find_validation_entry (struct GNUNET_PeerIdentity *neighbour,
+find_validation_entry (const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *public_key,
+ const struct GNUNET_PeerIdentity *neighbour,
const char *tname,
const char *addr,
size_t addrlen)
&vemc);
if (NULL != (ve = vemc.ve))
return ve;
+ if (public_key == NULL)
+ return NULL;
ve = GNUNET_malloc (sizeof (struct ValidationEntry) + addrlen);
ve->transport_name = GNUNET_strdup (tname);
ve->addr = (void*) &ve[1];
+ ve->public_key = *public_key;
ve->pid = *neighbour;
+ ve->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
+ UINT32_MAX);
memcpy (&ve[1], addr, addrlen);
ve->addrlen = addrlen;
- ve->last_validated_at = GNUNET_TIME_UNIT_FOREVER_ABS;
GNUNET_CONTAINER_multihashmap_put (validation_map,
&neighbour->hashPubKey,
ve,
}
+/**
+ * Iterator which adds the given address to the set of validated
+ * addresses.
+ *
+ * @param cls original HELLO message
+ * @param tname name of the transport
+ * @param expiration expiration time
+ * @param addr the address
+ * @param addrlen length of the address
+ * @return GNUNET_OK (keep the address)
+ */
+static int
+add_valid_address (void *cls,
+ const char *tname,
+ struct GNUNET_TIME_Absolute expiration,
+ const void *addr,
+ uint16_t addrlen)
+{
+ const struct GNUNET_HELLO_Message *hello = cls;
+ struct ValidationEntry *ve;
+ struct GNUNET_PeerIdentity pid;
+ struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded public_key;
+
+ if (GNUNET_TIME_absolute_get_remaining (expiration).rel_value == 0)
+ return GNUNET_OK; /* expired */
+ if ( (GNUNET_OK !=
+ GNUNET_HELLO_get_id (hello, &pid)) ||
+ (GNUNET_OK !=
+ GNUNET_HELLO_get_key (hello, &public_key)) )
+ {
+ GNUNET_break (0);
+ return GNUNET_OK; /* invalid HELLO !? */
+ }
+
+ ve = find_validation_entry (&public_key, &pid, tname, addr, addrlen);
+ ve->valid_until = GNUNET_TIME_absolute_max (ve->valid_until,
+ expiration);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Function called for any HELLO known to PEERINFO.
+ *
+ * @param cls unused
+ * @param peer id of the peer, NULL for last call
+ * @param hello hello message for the peer (can be NULL)
+ * @param error message
+ */
+static void
+process_peerinfo_hello (void *cls,
+ const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_HELLO_Message *hello,
+ const char *err_msg)
+{
+ GNUNET_assert (NULL != peer);
+ if (NULL == hello)
+ return;
+ GNUNET_assert (NULL ==
+ GNUNET_HELLO_iterate_addresses (hello,
+ GNUNET_NO,
+ &add_valid_address,
+ (void*) hello));
+}
+
+
+/**
+ * Start the validation subsystem.
+ */
+void
+GST_validation_start ()
+{
+ validation_map = GNUNET_CONTAINER_multihashmap_create (VALIDATION_MAP_SIZE);
+ notify_map = GNUNET_CONTAINER_multihashmap_create (VALIDATION_MAP_SIZE);
+ pnc = GNUNET_PEERINFO_notify (GST_cfg,
+ &process_peerinfo_hello,
+ NULL);
+}
+
+
+/**
+ * Iterate over validation entries and free them.
+ *
+ * @param cls (unused)
+ * @param key peer identity (unused)
+ * @param value a 'struct ValidationEntry' to clean up
+ * @return GNUNET_YES (continue to iterate)
+ */
+static int
+cleanup_validation_entry (void *cls,
+ const GNUNET_HashCode *key,
+ void *value)
+{
+ struct ValidationEntry *ve = value;
+
+ GNUNET_free (ve->transport_name);
+ if (GNUNET_SCHEDULER_NO_TASK != ve->timeout_task)
+ {
+ GNUNET_SCHEDULER_cancel (ve->timeout_task);
+ ve->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+ }
+ GNUNET_free (ve);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Stop the validation subsystem.
+ */
+void
+GST_validation_stop ()
+{
+ struct CheckHelloValidatedContext *chvc;
+
+ GNUNET_CONTAINER_multihashmap_iterate (validation_map,
+ &cleanup_validation_entry,
+ NULL);
+ GNUNET_CONTAINER_multihashmap_destroy (validation_map);
+ validation_map = NULL;
+ GNUNET_assert (GNUNET_CONTAINER_multihashmap_size (notify_map) == 0);
+ GNUNET_CONTAINER_multihashmap_destroy (notify_map);
+ notify_map = NULL;
+ while (NULL != (chvc = chvc_head))
+ {
+ GNUNET_CONTAINER_DLL_remove (chvc_head,
+ chvc_tail,
+ chvc);
+ GNUNET_free (chvc);
+ }
+ GNUNET_PEERINFO_notify_cancel (pnc);
+}
+
+
+/**
+ * Address validation cleanup task (record no longer needed).
+ *
+ * @param cls the 'struct ValidationEntry'
+ * @param tc scheduler context (unused)
+ */
+static void
+timeout_hello_validation (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct ValidationEntry *va = cls;
+
+ va->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+ GNUNET_STATISTICS_update (GST_stats,
+ gettext_noop ("# address records discarded"),
+ 1,
+ GNUNET_NO);
+ GNUNET_break (GNUNET_OK ==
+ GNUNET_CONTAINER_multihashmap_remove (validation_map,
+ &va->pid.hashPubKey,
+ va));
+ GNUNET_free (va->transport_name);
+ GNUNET_free (va);
+}
+
+
+/**
+ * Send the given PONG to the given address.
+ *
+ * @param cls the PONG message
+ * @param public_key public key for the peer, never NULL
+ * @param target peer this change is about, never NULL
+ * @param valid_until is ZERO if we never validated the address,
+ * otherwise a time up to when we consider it (or was) valid
+ * @param validation_block is FOREVER if the address is for an unsupported plugin (from PEERINFO)
+ * is ZERO if the address is considered valid (no validation needed)
+ * otherwise a time in the future if we're currently denying re-validation
+ * @param plugin_name name of the plugin
+ * @param plugin_address binary address
+ * @param plugin_address_len length of address
+ */
+static void
+multicast_pong (void *cls,
+ const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *public_key,
+ const struct GNUNET_PeerIdentity *target,
+ struct GNUNET_TIME_Absolute valid_until,
+ struct GNUNET_TIME_Absolute validation_block,
+ const char *plugin_name,
+ const void *plugin_address,
+ size_t plugin_address_len)
+{
+ struct TransportPongMessage *pong = cls;
+ struct GNUNET_TRANSPORT_PluginFunctions *papi;
+
+ papi = GST_plugins_find (plugin_name);
+ if (papi == NULL)
+ return;
+ (void) papi->send (papi->cls,
+ target,
+ (const char*) pong,
+ ntohs (pong->header.size),
+ PONG_PRIORITY,
+ HELLO_REVALIDATION_START_TIME,
+ NULL,
+ plugin_address,
+ plugin_address_len,
+ GNUNET_YES,
+ NULL, NULL);
+}
+
+
/**
* We've received a PING. If appropriate, generate a PONG.
*
* @param sender peer sending the PING
* @param hdr the PING
+ * @param session session we got the PING from
* @param plugin_name name of plugin that received the PING
* @param sender_address address of the sender as known to the plugin, NULL
* if we did not initiate the connection
GST_validation_handle_ping (const struct GNUNET_PeerIdentity *sender,
const struct GNUNET_MessageHeader *hdr,
const char *plugin_name,
+ struct Session *session,
const void *sender_address,
size_t sender_address_len)
{
+
+ const struct TransportPingMessage *ping;
+ struct TransportPongMessage *pong;
+ struct GNUNET_TRANSPORT_PluginFunctions *papi;
+ struct SessionHeader *session_header;
+ const char *addr;
+ const char *addrend;
+ size_t alen;
+ size_t slen;
+ ssize_t ret;
+
+ if (ntohs (hdr->size) < sizeof (struct TransportPingMessage))
+ {
+ GNUNET_break_op (0);
+ return;
+ }
+ ping = (const struct TransportPingMessage *) hdr;
+ if (0 != memcmp (&ping->target,
+ &GST_my_identity,
+ sizeof (struct GNUNET_PeerIdentity)))
+ {
+#if DEBUG_TRANSPORT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ _("Received `%s' message from `%s' destined for `%s' which is not me!\n"),
+ "PING",
+ (sender_address != NULL)
+ ? GST_plugin_a2s (plugin_name,
+ sender_address,
+ sender_address_len)
+ : "<inbound>",
+ GNUNET_i2s (&ping->target));
+#endif
+ return;
+ }
+#if DEBUG_TRANSPORT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
+ "Processing `%s' from `%s'\n",
+ "PING",
+ (sender_address != NULL)
+ ? GST_plugin_a2s (plugin_name,
+ sender_address,
+ sender_address_len)
+ : "<inbound>");
+#endif
+ GNUNET_STATISTICS_update (GST_stats,
+ gettext_noop ("# PING messages received"),
+ 1,
+ GNUNET_NO);
+ addr = (const char*) &ping[1];
+ alen = ntohs (hdr->size) - sizeof (struct TransportPingMessage);
+ if (alen == 0)
+ {
+ /* peer wants to confirm that we have an outbound connection to him;
+ we handle this case here even though it has nothing to do with
+ address validation (!) */
+ if ( (sender_address == NULL) || (session == NULL) )
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ _("Refusing to create PONG since I do initiate the session with `%s'.\n"),
+ GNUNET_i2s (sender));
+ return;
+ }
+ session_header = (struct SessionHeader *)session;
+#if DEBUG_TRANSPORT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Creating PONG indicating that we initiated a connection to peer `%s' using address `%s' \n",
+ GNUNET_i2s (peer),
+ GST_plugin_a2s (plugin_name,
+ sender_address,
+ sender_address_len));
+#endif
+ slen = strlen (plugin_name) + 1;
+ pong = GNUNET_malloc (sizeof (struct TransportPongMessage) + sender_address_len + slen);
+ pong->header.size = htons (sizeof (struct TransportPongMessage) + sender_address_len + slen);
+ pong->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_PONG);
+ pong->purpose.size =
+ htonl (sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
+ sizeof (uint32_t) +
+ sizeof (struct GNUNET_TIME_AbsoluteNBO) +
+ sizeof (struct GNUNET_PeerIdentity) + sender_address_len + slen);
+ pong->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_PONG_USING);
+ pong->challenge = ping->challenge;
+ pong->addrlen = htonl(sender_address_len + slen);
+ pong->pid = *sender;
+ memcpy (&pong[1],
+ plugin_name,
+ slen);
+ memcpy (&((char*)&pong[1])[slen],
+ sender_address,
+ sender_address_len);
+ if (GNUNET_TIME_absolute_get_remaining (session_header->pong_sig_expires).rel_value <
+ PONG_SIGNATURE_LIFETIME.rel_value / 4)
+ {
+ /* create / update cached sig */
+#if DEBUG_TRANSPORT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Creating PONG signature to indicate active connection.\n");
+#endif
+ session_header->pong_sig_expires = GNUNET_TIME_relative_to_absolute (PONG_SIGNATURE_LIFETIME);
+ pong->expiration = GNUNET_TIME_absolute_hton (session_header->pong_sig_expires);
+ GNUNET_assert (GNUNET_OK ==
+ GNUNET_CRYPTO_rsa_sign (GST_my_private_key,
+ &pong->purpose,
+ &session_header->pong_signature));
+ }
+ else
+ {
+ pong->expiration = GNUNET_TIME_absolute_hton (session_header->pong_sig_expires);
+ }
+ pong->signature = session_header->pong_signature;
+ }
+ else
+ {
+ /* peer wants to confirm that this is one of our addresses, this is what is
+ used for address validation */
+ struct GNUNET_CRYPTO_RsaSignature *sig_cache;
+ struct GNUNET_TIME_Absolute *sig_cache_exp;
+
+ addrend = memchr (addr, '\0', alen);
+ if (NULL == addrend)
+ {
+ GNUNET_break_op (0);
+ return;
+ }
+ addrend++;
+ slen = strlen(addr);
+ alen -= slen;
+
+ if (GNUNET_YES !=
+ GST_hello_test_address (addr,
+ addrend,
+ alen,
+ &sig_cache,
+ &sig_cache_exp))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ _("Not confirming PING with address `%s' since I cannot confirm having this address.\n"),
+ GST_plugins_a2s (addr,
+ addrend,
+ alen));
+ return;
+ }
+
+ pong = GNUNET_malloc (sizeof (struct TransportPongMessage) + alen + slen);
+ pong->header.size = htons (sizeof (struct TransportPongMessage) + alen + slen);
+ pong->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_PONG);
+ pong->purpose.size =
+ htonl (sizeof (struct GNUNET_CRYPTO_RsaSignaturePurpose) +
+ sizeof (uint32_t) +
+ sizeof (struct GNUNET_TIME_AbsoluteNBO) +
+ sizeof (struct GNUNET_PeerIdentity) + alen + slen);
+ pong->purpose.purpose = htonl (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_PONG_OWN);
+ pong->challenge = ping->challenge;
+ pong->addrlen = htonl(alen + slen);
+ pong->pid = GST_my_identity;
+ memcpy (&pong[1], addr, slen);
+ memcpy (&((char*)&pong[1])[slen], addrend, alen);
+ if (GNUNET_TIME_absolute_get_remaining (*sig_cache_exp).rel_value < PONG_SIGNATURE_LIFETIME.rel_value / 4)
+ {
+ /* create / update cached sig */
+#if DEBUG_TRANSPORT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Creating PONG signature to indicate ownership.\n");
+#endif
+ *sig_cache_exp = GNUNET_TIME_relative_to_absolute (PONG_SIGNATURE_LIFETIME);
+ pong->expiration = GNUNET_TIME_absolute_hton (*sig_cache_exp);
+ GNUNET_assert (GNUNET_OK ==
+ GNUNET_CRYPTO_rsa_sign (GST_my_private_key,
+ &pong->purpose,
+ sig_cache));
+ }
+ else
+ {
+ pong->expiration = GNUNET_TIME_absolute_hton (*sig_cache_exp);
+ }
+ pong->signature = *sig_cache;
+ }
+
+ /* first see if the session we got this PING from can be used to transmit
+ a response reliably */
+ papi = GST_plugins_find (plugin_name);
+ if (papi == NULL)
+ ret = -1;
+ else
+ ret = papi->send (papi->cls,
+ sender,
+ (const char*) pong,
+ ntohs (pong->header.size),
+ PONG_PRIORITY,
+ HELLO_REVALIDATION_START_TIME,
+ session,
+ sender_address,
+ sender_address_len,
+ GNUNET_SYSERR,
+ NULL, NULL);
+ if (ret != -1)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmitted PONG to `%s' via reliable mechanism\n",
+ GNUNET_i2s (sender));
+ /* done! */
+ GNUNET_STATISTICS_update (GST_stats,
+ gettext_noop ("# PONGs unicast via reliable transport"),
+ 1,
+ GNUNET_NO);
+ GNUNET_free (pong);
+ return;
+ }
+
+ /* no reliable method found, try transmission via all known addresses */
+ GNUNET_STATISTICS_update (GST_stats,
+ gettext_noop ("# PONGs multicast to all available addresses"),
+ 1,
+ GNUNET_NO);
+ (void) GST_validation_get_addresses (sender,
+ GNUNET_YES,
+ &multicast_pong,
+ pong);
+ GNUNET_free (pong);
}
/**
- * We've received a PONG. Check if it matches a pending PING and
- * mark the respective address as confirmed.
- *
- * @param sender peer sending the PONG
- * @param hdr the PONG
- * @param plugin_name name of plugin that received the PONG
- * @param sender_address address of the sender as known to the plugin, NULL
- * if we did not initiate the connection
- * @param sender_address_len number of bytes in sender_address
+ * Context for the 'validate_address' function
*/
-void
-GST_validation_handle_pong (const struct GNUNET_PeerIdentity *sender,
- const struct GNUNET_MessageHeader *hdr,
- const char *plugin_name,
- const void *sender_address,
- size_t sender_address_len)
+struct ValidateAddressContext
{
-}
+ /**
+ * Hash of the public key of the peer whose address is being validated.
+ */
+ struct GNUNET_PeerIdentity pid;
+
+ /**
+ * Public key of the peer whose address is being validated.
+ */
+ struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded public_key;
+};
/**
* Iterator callback to go over all addresses and try to validate them
* (unless blocked or already validated).
*
- * @param cls pointer to the 'struct PeerIdentity' of the peer
+ * @param cls pointer to a 'struct ValidateAddressContext'
* @param tname name of the transport
* @param expiration expiration time
* @param addr the address
const void *addr,
uint16_t addrlen)
{
- struct GNUNET_PeerIdentity *pid = cls;
+ const struct ValidateAddressContext *vac = cls;
+ const struct GNUNET_PeerIdentity *pid = &vac->pid;
struct ValidationEntry *ve;
-
+ struct TransportPingMessage ping;
+ struct GNUNET_TRANSPORT_PluginFunctions *papi;
+ ssize_t ret;
+ size_t tsize;
+ size_t slen;
+
if (GNUNET_TIME_absolute_get_remaining (expiration).rel_value == 0)
return GNUNET_OK; /* expired */
- ve = find_validation_entry (pid, tname, addr, addrlen);
- // FIXME: check if validated/blocked, if not start validation...
- ve++; // make compiler happy
+ ve = find_validation_entry (&vac->public_key, pid, tname, addr, addrlen);
+ if (GNUNET_TIME_absolute_get_remaining (ve->validation_block).rel_value > 0)
+ return GNUNET_OK; /* blocked */
+ if ( (GNUNET_SCHEDULER_NO_TASK != ve->timeout_task) &&
+ (GNUNET_TIME_absolute_get_remaining (ve->valid_until).rel_value > 0) )
+ return GNUNET_OK; /* revalidation task already scheduled & still valid */
+ ve->validation_block = GNUNET_TIME_relative_to_absolute (HELLO_REVALIDATION_START_TIME);
+ if (GNUNET_SCHEDULER_NO_TASK != ve->timeout_task)
+ GNUNET_SCHEDULER_cancel (ve->timeout_task);
+ ve->timeout_task = GNUNET_SCHEDULER_add_delayed (HELLO_REVALIDATION_START_TIME,
+ &timeout_hello_validation,
+ ve);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmitting plain PING to `%s'\n",
+ GNUNET_i2s (pid));
+ ping.header.size = htons(sizeof(struct TransportPingMessage));
+ ping.header.type = htons(GNUNET_MESSAGE_TYPE_TRANSPORT_PING);
+ ping.challenge = htonl(ve->challenge);
+ ping.target = *pid;
+
+ slen = strlen(ve->transport_name) + 1;
+ tsize = sizeof(struct TransportPingMessage) + ve->addrlen + slen;
+ {
+ char message_buf[tsize];
+
+ memcpy(message_buf, &ping, sizeof (struct TransportPingMessage));
+ memcpy(&message_buf[sizeof (struct TransportPingMessage)],
+ ve->transport_name,
+ slen);
+ memcpy(&message_buf[sizeof (struct TransportPingMessage) + slen],
+ ve->addr,
+ ve->addrlen);
+ papi = GST_plugins_find (ve->transport_name);
+ if (papi == NULL)
+ ret = -1;
+ else
+ ret = papi->send (papi->cls,
+ pid,
+ message_buf,
+ tsize,
+ PING_PRIORITY,
+ HELLO_REVALIDATION_START_TIME,
+ NULL /* no session */,
+ ve->addr,
+ ve->addrlen,
+ GNUNET_YES,
+ NULL, NULL);
+ }
+ if (-1 != ret)
+ {
+ ve->send_time = GNUNET_TIME_absolute_get ();
+ GNUNET_STATISTICS_update (GST_stats,
+ gettext_noop ("# PING without HELLO messages sent"),
+ 1,
+ GNUNET_NO);
+ }
return GNUNET_OK;
}
+/**
+ * Do address validation again to keep address valid.
+ *
+ * @param cls the 'struct ValidationEntry'
+ * @param tc scheduler context (unused)
+ */
+static void
+revalidate_address (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct ValidationEntry *ve = cls;
+ struct GNUNET_TIME_Relative delay;
+ struct ValidateAddressContext vac;
+
+ ve->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+ delay = GNUNET_TIME_absolute_get_remaining (ve->validation_block);
+ if (delay.rel_value > 0)
+ {
+ /* should wait a bit longer */
+ ve->timeout_task = GNUNET_SCHEDULER_add_delayed (delay,
+ &revalidate_address,
+ ve);
+ return;
+ }
+ GNUNET_STATISTICS_update (GST_stats,
+ gettext_noop ("# address revalidations started"),
+ 1,
+ GNUNET_NO);
+ vac.pid = ve->pid;
+ vac.public_key = ve->public_key;
+ validate_address (&vac,
+ ve->transport_name,
+ ve->valid_until,
+ ve->addr,
+ (uint16_t) ve->addrlen);
+}
+
+
+/**
+ * Add the validated peer address to the HELLO.
+ *
+ * @param cls the 'struct ValidationEntry' with the validated address
+ * @param max space in buf
+ * @param buf where to add the address
+ */
+static size_t
+add_valid_peer_address (void *cls,
+ size_t max,
+ void *buf)
+{
+ struct ValidationEntry *ve = cls;
+
+ return GNUNET_HELLO_add_address (ve->transport_name,
+ ve->valid_until,
+ ve->addr,
+ ve->addrlen,
+ buf,
+ max);
+}
+
+
+/**
+ * We've received a PONG. Check if it matches a pending PING and
+ * mark the respective address as confirmed.
+ *
+ * @param sender peer sending the PONG
+ * @param hdr the PONG
+ * @param plugin_name name of plugin that received the PONG
+ * @param sender_address address of the sender as known to the plugin, NULL
+ * if we did not initiate the connection
+ * @param sender_address_len number of bytes in sender_address
+ */
+void
+GST_validation_handle_pong (const struct GNUNET_PeerIdentity *sender,
+ const struct GNUNET_MessageHeader *hdr,
+ const char *plugin_name,
+ const void *sender_address,
+ size_t sender_address_len)
+{
+ const struct TransportPongMessage *pong;
+ struct ValidationEntry *ve;
+ const char *addr;
+ const char *addrend;
+ size_t alen;
+ size_t slen;
+ uint32_t rdelay;
+ struct GNUNET_TIME_Relative delay;
+ struct GNUNET_HELLO_Message *hello;
+
+ if (ntohs (hdr->size) < sizeof (struct TransportPongMessage))
+ {
+ GNUNET_break_op (0);
+ return;
+ }
+ GNUNET_STATISTICS_update (GST_stats,
+ gettext_noop ("# PONG messages received"),
+ 1,
+ GNUNET_NO);
+ pong = (const struct TransportPongMessage *) hdr;
+ if (0 != memcmp (&pong->pid,
+ sender,
+ sizeof (struct GNUNET_PeerIdentity)))
+ {
+ /* PONG is validating inbound session, not an address, not the case
+ used for address validation, ignore here! */
+ return;
+ }
+#if DEBUG_TRANSPORT
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
+ "Processing `%s' from `%s'\n",
+ "PONG",
+ (sender_address != NULL)
+ ? GST_plugin_a2s (plugin_name,
+ sender_address,
+ sender_address_len)
+ : "<inbound>");
+#endif
+ addr = (const char*) &pong[1];
+ alen = ntohs (hdr->size) - sizeof (struct TransportPongMessage);
+ addrend = memchr (addr, '\0', alen);
+ if (NULL == addrend)
+ {
+ GNUNET_break_op (0);
+ return;
+ }
+ addrend++;
+ slen = strlen(addr);
+ alen -= slen;
+ ve = find_validation_entry (NULL,
+ sender,
+ addr,
+ addrend,
+ alen);
+ if (NULL == ve)
+ {
+ GNUNET_STATISTICS_update (GST_stats,
+ gettext_noop ("# PONGs dropped, no matching pending validation"),
+ 1,
+ GNUNET_NO);
+ return;
+ }
+ /* now check that PONG is well-formed */
+ if (GNUNET_TIME_absolute_get_remaining (GNUNET_TIME_absolute_ntoh (pong->expiration)).rel_value == 0)
+ {
+ GNUNET_STATISTICS_update (GST_stats,
+ gettext_noop ("# PONGs dropped, signature expired"),
+ 1,
+ GNUNET_NO);
+ return;
+ }
+ if (GNUNET_OK !=
+ GNUNET_CRYPTO_rsa_verify (GNUNET_SIGNATURE_PURPOSE_TRANSPORT_PONG_OWN,
+ &pong->purpose,
+ &pong->signature,
+ &ve->public_key))
+ {
+ GNUNET_break_op (0);
+ return;
+ }
+
+ /* validity achieved, remember it! */
+ ve->valid_until = GNUNET_TIME_relative_to_absolute (HELLO_ADDRESS_EXPIRATION);
+
+ /* build HELLO to store in PEERINFO */
+ hello = GNUNET_HELLO_create (&ve->public_key,
+ &add_valid_peer_address,
+ ve);
+ GNUNET_PEERINFO_add_peer (GST_peerinfo,
+ hello);
+ GNUNET_free (hello);
+
+ if (GNUNET_SCHEDULER_NO_TASK != ve->timeout_task)
+ GNUNET_SCHEDULER_cancel (ve->timeout_task);
+
+ /* randomly delay by up to 1h to avoid synchronous validations */
+ rdelay = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
+ 60 * 60);
+ delay = GNUNET_TIME_relative_add (HELLO_REVALIDATION_START_TIME,
+ GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS,
+ rdelay));
+ ve->timeout_task = GNUNET_SCHEDULER_add_delayed (delay,
+ &revalidate_address,
+ ve);
+}
+
/**
* We've received a HELLO, check which addresses are new and trigger
GST_validation_handle_hello (const struct GNUNET_MessageHeader *hello)
{
const struct GNUNET_HELLO_Message* hm = (const struct GNUNET_HELLO_Message*) hello;
- struct GNUNET_PeerIdentity pid;
+ struct ValidateAddressContext vac;
- if (GNUNET_OK !=
- GNUNET_HELLO_get_id (hm, &pid))
+ if ( (GNUNET_OK !=
+ GNUNET_HELLO_get_id (hm, &vac.pid)) ||
+ (GNUNET_OK !=
+ GNUNET_HELLO_get_key (hm, &vac.public_key)) )
{
/* malformed HELLO */
GNUNET_break (0);
GNUNET_HELLO_iterate_addresses (hm,
GNUNET_NO,
&validate_address,
- &pid));
+ &vac));
}
struct ValidationEntry *ve = value;
vic->cb (vic->cb_cls,
+ &ve->public_key,
&ve->pid,
- ve->last_validated_at,
+ ve->valid_until,
ve->validation_block,
ve->transport_name,
ve->addr,