/*
This file is part of GNUnet.
- Copyright (C) 2010, 2012 Christian Grothoff
+ Copyright (C) 2010, 2012, 2017 Christian Grothoff
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
-
/**
* @file pt/gnunet-daemon-pt.c
* @brief tool to manipulate DNS and VPN services to perform protocol translation (IPvX over GNUnet)
*/
struct RequestContext *receive_queue_tail;
- /**
- * Head of DLL of requests to be transmitted to a cadet_channel.
- */
- struct RequestContext *transmit_queue_head;
-
- /**
- * Tail of DLL of requests to be transmitted to a cadet_channel.
- */
- struct RequestContext *transmit_queue_tail;
-
- /**
- * Active transmission request for this channel (or NULL).
- */
- struct GNUNET_CADET_TransmitHandle *cadet_th;
-
/**
* Identity of the peer that is providing the exit for us.
*/
*/
unsigned int num_answered;
+ /**
+ * Size of the window, 0 if we are busy.
+ */
+ /* unsigned */ int idle;
+
};
struct GNUNET_DNS_RequestHandle *rh;
/**
- * Message we're sending out via CADET, allocated at the
- * end of this struct.
+ * Envelope with the request we are transmitting.
*/
- const struct GNUNET_MessageHeader *cadet_message;
+ struct GNUNET_MQ_Envelope *env;
/**
* Task used to abort this operation with timeout.
*/
uint16_t dns_id;
- /**
- * #GNUNET_NO if this request is still in the transmit_queue,
- * #GNUNET_YES if we are in the receive_queue.
- */
- int16_t was_transmitted;
-
};
* We are short on cadet exits, try to open another one.
*/
static void
-try_open_exit ()
-{
- struct CadetExit *pos;
- uint32_t candidate_count;
- uint32_t candidate_selected;
- struct GNUNET_HashCode port;
-
- GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_INTERNET_RESOLVER,
- strlen (GNUNET_APPLICATION_PORT_INTERNET_RESOLVER),
- &port);
- candidate_count = 0;
- for (pos = exit_head; NULL != pos; pos = pos->next)
- if (NULL == pos->cadet_channel)
- candidate_count++;
- if (0 == candidate_count)
- {
- GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
- "No DNS exits available yet.\n");
- return;
- }
- candidate_selected = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
- candidate_count);
- candidate_count = 0;
- for (pos = exit_head; NULL != pos; pos = pos->next)
- if (NULL == pos->cadet_channel)
- {
- candidate_count++;
- if (candidate_selected < candidate_count)
- {
- /* move to the head of the DLL */
- pos->cadet_channel
- = GNUNET_CADET_channel_create (cadet_handle,
- pos,
- &pos->peer,
- &port,
- GNUNET_CADET_OPTION_DEFAULT);
- if (NULL == pos->cadet_channel)
- {
- GNUNET_break (0);
- continue;
- }
- GNUNET_CONTAINER_DLL_remove (exit_head,
- exit_tail,
- pos);
- GNUNET_CONTAINER_DLL_insert (exit_head,
- exit_tail,
- pos);
- dns_exit_available++;
- return;
- }
- }
- GNUNET_assert (NULL == exit_head);
-}
+try_open_exit (void);
/**
channel_weight = get_channel_weight (pos);
total_transmitted += channel_weight;
/* double weight for idle channels */
- if (NULL == pos->cadet_th)
+ if (0 != pos->idle)
total_transmitted += channel_weight;
}
if (0 == total_transmitted)
channel_weight = get_channel_weight (pos);
total_transmitted += channel_weight;
/* double weight for idle channels */
- if (NULL == pos->cadet_th)
+ if (0 != pos->idle)
total_transmitted += channel_weight;
if (total_transmitted > selected_offset)
return pos;
}
-/**
- * Transmit a DNS request via CADET and move the request
- * handle to the receive queue.
- *
- * @param cls the `struct CadetExit`
- * @param size number of bytes available in buf
- * @param buf where to copy the message
- * @return number of bytes written to buf
- */
-static size_t
-transmit_dns_request_to_cadet (void *cls,
- size_t size,
- void *buf)
-{
- struct CadetExit *exit = cls;
- struct RequestContext *rc;
- size_t mlen;
-
- exit->cadet_th = NULL;
- if (NULL == (rc = exit->transmit_queue_head))
- return 0;
- mlen = rc->mlen;
- if (mlen > size)
- {
- exit->cadet_th
- = GNUNET_CADET_notify_transmit_ready (exit->cadet_channel,
- GNUNET_NO,
- TIMEOUT,
- mlen,
- &transmit_dns_request_to_cadet,
- exit);
- return 0;
- }
- GNUNET_assert (GNUNET_NO == rc->was_transmitted);
- GNUNET_memcpy (buf,
- rc->cadet_message,
- mlen);
- GNUNET_CONTAINER_DLL_remove (exit->transmit_queue_head,
- exit->transmit_queue_tail,
- rc);
- rc->was_transmitted = GNUNET_YES;
- GNUNET_CONTAINER_DLL_insert (exit->receive_queue_head,
- exit->receive_queue_tail,
- rc);
- rc = exit->transmit_queue_head;
- if (NULL != rc)
- exit->cadet_th = GNUNET_CADET_notify_transmit_ready (exit->cadet_channel,
- GNUNET_NO,
- TIMEOUT,
- rc->mlen,
- &transmit_dns_request_to_cadet,
- exit);
- return mlen;
-}
-
-
/**
* Task run if the time to answer a DNS request via CADET is over.
*
struct RequestContext *rc = cls;
struct CadetExit *exit = rc->exit;
- if (rc->was_transmitted)
- {
- exit->num_transmitted++;
- GNUNET_CONTAINER_DLL_remove (exit->receive_queue_head,
- exit->receive_queue_tail,
- rc);
- }
- else
- {
- GNUNET_CONTAINER_DLL_remove (exit->transmit_queue_head,
- exit->transmit_queue_tail,
- rc);
- }
GNUNET_STATISTICS_update (stats,
gettext_noop ("# DNS requests dropped (timeout)"),
1,
GNUNET_DNS_request_drop (rc->rh);
GNUNET_free (rc);
if ( (0 == get_channel_weight (exit)) &&
- (NULL == exit->receive_queue_head) &&
- (NULL == exit->transmit_queue_head) )
+ (NULL == exit->receive_queue_head) )
{
/* this straw broke the camel's back: this channel now has
such a low score that it will not be used; close it! */
- GNUNET_assert (NULL == exit->cadet_th);
GNUNET_CADET_channel_destroy (exit->cadet_channel);
exit->cadet_channel = NULL;
GNUNET_CONTAINER_DLL_remove (exit_head,
exit);
/* go back to semi-innocent: mark as not great, but
avoid a prohibitively negative score (see
- #get_channel_weight, which checks for a certain
+ #get_channel_weight(), which checks for a certain
minimum number of transmissions before making
up an opinion) */
exit->num_transmitted = 5;
const char *request)
{
struct RequestContext *rc;
- size_t mlen;
- struct GNUNET_MessageHeader hdr;
+ struct GNUNET_MQ_Envelope *env;
+ struct GNUNET_MessageHeader *hdr;
struct GNUNET_TUN_DnsHeader dns;
struct CadetExit *exit;
GNUNET_DNS_request_drop (rh);
return;
}
- GNUNET_memcpy (&dns, request, sizeof (dns));
- mlen = sizeof (struct GNUNET_MessageHeader) + request_length;
exit = choose_exit ();
GNUNET_assert (NULL != exit);
GNUNET_assert (NULL != exit->cadet_channel);
- rc = GNUNET_malloc (sizeof (struct RequestContext) + mlen);
+
+ env = GNUNET_MQ_msg_extra (hdr,
+ request_length,
+ GNUNET_MESSAGE_TYPE_VPN_DNS_TO_INTERNET);
+ GNUNET_memcpy (&hdr[1],
+ request,
+ request_length);
+ rc = GNUNET_new (struct RequestContext);
rc->exit = exit;
rc->rh = rh;
- rc->cadet_message = (const struct GNUNET_MessageHeader*) &rc[1];
rc->timeout_task = GNUNET_SCHEDULER_add_delayed (TIMEOUT,
&timeout_request,
rc);
+ GNUNET_memcpy (&dns,
+ request,
+ sizeof (dns));
rc->dns_id = dns.id;
- rc->mlen = mlen;
- hdr.type = htons (GNUNET_MESSAGE_TYPE_VPN_DNS_TO_INTERNET);
- hdr.size = htons (mlen);
- GNUNET_memcpy (&rc[1], &hdr, sizeof (struct GNUNET_MessageHeader));
- GNUNET_memcpy (&(((char*)&rc[1])[sizeof (struct GNUNET_MessageHeader)]),
- request,
- request_length);
- GNUNET_CONTAINER_DLL_insert_tail (exit->transmit_queue_head,
- exit->transmit_queue_tail,
- rc);
- if (NULL == exit->cadet_th)
- exit->cadet_th = GNUNET_CADET_notify_transmit_ready (exit->cadet_channel,
- GNUNET_NO,
- TIMEOUT,
- mlen,
- &transmit_dns_request_to_cadet,
- exit);
+ rc->env = env;
+ GNUNET_CONTAINER_DLL_remove (exit->receive_queue_head,
+ exit->receive_queue_tail,
+ rc);
+ if (0 < exit->idle)
+ exit->idle--;
+ exit->num_transmitted++;
+ GNUNET_MQ_send (GNUNET_CADET_get_mq (exit->cadet_channel),
+ GNUNET_MQ_env_copy (env));
}
+GNUNET_NETWORK_STRUCT_BEGIN
+
+/**
+ * Message with a DNS response.
+ */
+struct DnsResponseMessage
+{
+ /**
+ * GNUnet header, of type #GNUNET_MESSAGE_TYPE_VPN_DNS_FROM_INTERNET
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * DNS header.
+ */
+ struct GNUNET_TUN_DnsHeader dns;
+
+ /* Followed by more DNS payload */
+};
+
+GNUNET_NETWORK_STRUCT_END
+
/**
* Process a request via cadet to perform a DNS query.
*
- * @param cls NULL
- * @param channel connection to the other end
- * @param channel_ctx pointer to our `struct CadetExit`
- * @param message the actual message
+ * @param cls the `struct CadetExit` which got the message
+ * @param msg the actual message
* @return #GNUNET_OK to keep the connection open,
* #GNUNET_SYSERR to close it (signal serious error)
*/
static int
-receive_dns_response (void *cls,
- struct GNUNET_CADET_Channel *channel,
- void **channel_ctx,
- const struct GNUNET_MessageHeader *message)
+check_dns_response (void *cls,
+ const struct DnsResponseMessage *msg)
{
- struct CadetExit *exit = *channel_ctx;
+ return GNUNET_OK; /* all OK */
+}
+
+
+/**
+ * Process a request via cadet to perform a DNS query.
+ *
+ * @param cls the `struct CadetExit` which got the message
+ * @param msg the actual message
+ */
+static void
+handle_dns_response (void *cls,
+ const struct DnsResponseMessage *msg)
+{
+ struct CadetExit *exit = cls;
struct GNUNET_TUN_DnsHeader dns;
size_t mlen;
struct RequestContext *rc;
- mlen = ntohs (message->size);
- mlen -= sizeof (struct GNUNET_MessageHeader);
- if (mlen < sizeof (struct GNUNET_TUN_DnsHeader))
- {
- GNUNET_break_op (0);
- return GNUNET_SYSERR;
- }
- GNUNET_memcpy (&dns, &message[1], sizeof (dns));
+ mlen = ntohs (msg->header.size) - sizeof (*msg);
for (rc = exit->receive_queue_head; NULL != rc; rc = rc->next)
{
- GNUNET_assert (GNUNET_YES == rc->was_transmitted);
if (dns.id == rc->dns_id)
{
GNUNET_STATISTICS_update (stats,
gettext_noop ("# DNS replies received"),
- 1, GNUNET_NO);
+ 1,
+ GNUNET_NO);
GNUNET_DNS_request_answer (rc->rh,
- mlen,
- (const void*) &message[1]);
+ mlen + sizeof (struct GNUNET_TUN_DnsHeader),
+ (const void*) &msg->dns);
GNUNET_CONTAINER_DLL_remove (exit->receive_queue_head,
exit->receive_queue_tail,
rc);
GNUNET_SCHEDULER_cancel (rc->timeout_task);
+ GNUNET_MQ_discard (rc->env);
GNUNET_free (rc);
exit->num_answered++;
- exit->num_transmitted++;
- return GNUNET_OK;
+ return;
}
}
GNUNET_STATISTICS_update (stats,
gettext_noop ("# DNS replies dropped (too late?)"),
1, GNUNET_NO);
- return GNUNET_OK;
}
rc);
GNUNET_DNS_request_drop (rc->rh);
GNUNET_SCHEDULER_cancel (rc->timeout_task);
- GNUNET_free (rc);
- }
- while (NULL != (rc = exit->transmit_queue_head))
- {
- GNUNET_CONTAINER_DLL_remove (exit->transmit_queue_head,
- exit->transmit_queue_tail,
- rc);
- GNUNET_DNS_request_drop (rc->rh);
- GNUNET_SCHEDULER_cancel (rc->timeout_task);
+ GNUNET_MQ_discard (rc->env);
GNUNET_free (rc);
}
}
GNUNET_CONTAINER_DLL_remove (exit_head,
exit_tail,
exit);
- if (NULL != exit->cadet_th)
- {
- GNUNET_CADET_notify_transmit_ready_cancel (exit->cadet_th);
- exit->cadet_th = NULL;
- }
if (NULL != exit->cadet_channel)
{
GNUNET_CADET_channel_destroy (exit->cadet_channel);
*/
static void
cadet_channel_end_cb (void *cls,
- const struct GNUNET_CADET_Channel *channel,
- void *channel_ctx)
+ const struct GNUNET_CADET_Channel *channel)
{
- struct CadetExit *exit = channel_ctx;
+ struct CadetExit *exit = cls;
struct CadetExit *alt;
struct RequestContext *rc;
- if (NULL != exit->cadet_th)
- {
- GNUNET_CADET_notify_transmit_ready_cancel (exit->cadet_th);
- exit->cadet_th = NULL;
- }
exit->cadet_channel = NULL;
dns_exit_available--;
/* open alternative channels */
- try_open_exit ();
- if (NULL == exit->cadet_channel)
+ /* our channel is now closed, move our requests to an alternative
+ channel */
+ alt = choose_exit ();
+ while (NULL != (rc = exit->receive_queue_head))
{
- /* our channel is now closed, move our requests to an alternative
- channel */
- alt = choose_exit ();
- while (NULL != (rc = exit->transmit_queue_head))
- {
- GNUNET_CONTAINER_DLL_remove (exit->transmit_queue_head,
- exit->transmit_queue_tail,
- rc);
- rc->exit = alt;
- GNUNET_CONTAINER_DLL_insert (alt->transmit_queue_head,
- alt->transmit_queue_tail,
- rc);
- }
- while (NULL != (rc = exit->receive_queue_head))
- {
- GNUNET_CONTAINER_DLL_remove (exit->receive_queue_head,
- exit->receive_queue_tail,
- rc);
- rc->was_transmitted = GNUNET_NO;
- rc->exit = alt;
- GNUNET_CONTAINER_DLL_insert (alt->transmit_queue_head,
- alt->transmit_queue_tail,
- rc);
- }
+ GNUNET_CONTAINER_DLL_remove (exit->receive_queue_head,
+ exit->receive_queue_tail,
+ rc);
+ rc->exit = alt;
+ GNUNET_CONTAINER_DLL_insert (alt->receive_queue_head,
+ alt->receive_queue_tail,
+ rc);
+ GNUNET_MQ_send (GNUNET_CADET_get_mq (exit->cadet_channel),
+ GNUNET_MQ_env_copy (rc->env));
}
- else
+ try_open_exit ();
+}
+
+
+/**
+ * Function called whenever a channel has excess capacity.
+ *
+ * @param cls the `struct CadetExit`
+ * @param channel connection to the other end
+ * @param window_size how much capacity do we have
+ */
+static void
+channel_idle_notify_cb (void *cls,
+ const struct GNUNET_CADET_Channel *channel,
+ int window_size)
+{
+ struct CadetExit *pos = cls;
+
+ pos->idle = window_size;
+}
+
+
+/**
+ * We are short on cadet exits, try to open another one.
+ */
+static void
+try_open_exit ()
+{
+ struct CadetExit *pos;
+ uint32_t candidate_count;
+ uint32_t candidate_selected;
+ struct GNUNET_HashCode port;
+
+ GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_INTERNET_RESOLVER,
+ strlen (GNUNET_APPLICATION_PORT_INTERNET_RESOLVER),
+ &port);
+ candidate_count = 0;
+ for (pos = exit_head; NULL != pos; pos = pos->next)
+ if (NULL == pos->cadet_channel)
+ candidate_count++;
+ if (0 == candidate_count)
{
- /* the same peer was chosen, just make sure the queue processing is restarted */
- alt = exit;
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ "No DNS exits available yet.\n");
+ return;
}
- if ( (NULL == alt->cadet_th) &&
- (NULL != (rc = alt->transmit_queue_head)) )
- alt->cadet_th
- = GNUNET_CADET_notify_transmit_ready (alt->cadet_channel,
- GNUNET_NO,
- TIMEOUT,
- rc->mlen,
- &transmit_dns_request_to_cadet,
- alt);
+ candidate_selected = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
+ candidate_count);
+ candidate_count = 0;
+ for (pos = exit_head; NULL != pos; pos = pos->next)
+ if (NULL == pos->cadet_channel)
+ {
+ candidate_count++;
+ if (candidate_selected < candidate_count)
+ {
+ struct GNUNET_MQ_MessageHandler cadet_handlers[] = {
+ GNUNET_MQ_hd_var_size (dns_response,
+ GNUNET_MESSAGE_TYPE_VPN_DNS_FROM_INTERNET,
+ struct DnsResponseMessage,
+ pos),
+ GNUNET_MQ_handler_end ()
+ };
+
+
+ /* move to the head of the DLL */
+ pos->cadet_channel
+ = GNUNET_CADET_channel_creatE (cadet_handle,
+ pos,
+ &pos->peer,
+ &port,
+ GNUNET_CADET_OPTION_DEFAULT,
+ &channel_idle_notify_cb,
+ &cadet_channel_end_cb,
+ cadet_handlers);
+ if (NULL == pos->cadet_channel)
+ {
+ GNUNET_break (0);
+ continue;
+ }
+ GNUNET_CONTAINER_DLL_remove (exit_head,
+ exit_tail,
+ pos);
+ GNUNET_CONTAINER_DLL_insert (exit_head,
+ exit_tail,
+ pos);
+ dns_exit_available++;
+ return;
+ }
+ }
+ GNUNET_assert (NULL == exit_head);
}
}
if (dns_channel)
{
- static struct GNUNET_CADET_MessageHandler cadet_handlers[] = {
- {&receive_dns_response, GNUNET_MESSAGE_TYPE_VPN_DNS_FROM_INTERNET, 0},
- {NULL, 0, 0}
- };
-
dns_pre_handle
= GNUNET_DNS_connect (cfg,
GNUNET_DNS_FLAG_PRE_RESOLUTION,
GNUNET_SCHEDULER_shutdown ();
return;
}
- cadet_handle = GNUNET_CADET_connect (cfg,
- NULL,
- &cadet_channel_end_cb,
- cadet_handlers);
+ cadet_handle = GNUNET_CADET_connecT (cfg);
if (NULL == cadet_handle)
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
projects / oweals / gnunet.git / commitdiff