/*
This file is part of GNUnet.
- Copyright (C) 2009-2015 GNUnet e.V.
+ Copyright (C) 2009-2016 GNUnet e.V.
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
* Our connection to the resolver service, created on-demand, but then
* persists until error or shutdown.
*/
-static struct GNUNET_CLIENT_Connection *client;
+static struct GNUNET_MQ_Handle *mq;
/**
* Head of DLL of requests.
GNUNET_RESOLVER_HostnameCallback name_callback;
/**
- * Closure for the respective "callback".
+ * Closure for the callbacks.
*/
void *cls;
* Task handle for making reply callbacks in numeric lookups
* asynchronous, and for timeout handling.
*/
- struct GNUNET_SCHEDULER_Task * task;
+ struct GNUNET_SCHEDULER_Task *task;
/**
* Desired address family.
/**
* Check that the resolver service runs on localhost
* (or equivalent).
+ *
+ * @return #GNUNET_OK if the resolver is properly configured,
+ * #GNUNET_SYSERR otherwise.
*/
-static void
+static int
check_config ()
{
char *hostname;
"HOSTNAME",
&hostname))
{
- LOG (GNUNET_ERROR_TYPE_ERROR,
- _("Must specify `%s' for `%s' in configuration!\n"),
+ LOG (GNUNET_ERROR_TYPE_INFO,
+ _("Missing `%s' for `%s' in configuration, DNS resolution will be unavailable.\n"),
"HOSTNAME",
"resolver");
- GNUNET_assert (0);
+ return GNUNET_SYSERR;
}
- if ((1 != inet_pton (AF_INET, hostname, &v4)) ||
- (1 != inet_pton (AF_INET6, hostname, &v6)))
+ if ((1 == inet_pton (AF_INET, hostname, &v4)) ||
+ (1 == inet_pton (AF_INET6, hostname, &v6)))
{
GNUNET_free (hostname);
- return;
+ return GNUNET_OK;
}
i = 0;
while (NULL != loopback[i])
if (0 == strcasecmp (loopback[i++], hostname))
{
GNUNET_free (hostname);
- return;
+ return GNUNET_OK;
}
- LOG (GNUNET_ERROR_TYPE_ERROR,
- _("Must specify `%s' or numeric IP address for `%s' of `%s' in configuration!\n"),
+ LOG (GNUNET_ERROR_TYPE_INFO,
+ _("Missing `%s' or numeric IP address for `%s' of `%s' in configuration, DNS resolution will be unavailable.\n"),
"localhost",
"HOSTNAME",
"resolver");
GNUNET_free (hostname);
- GNUNET_assert (0);
+ return GNUNET_SYSERR;
}
GNUNET_assert (NULL != cfg);
backoff = GNUNET_TIME_UNIT_MILLISECONDS;
resolver_cfg = cfg;
- check_config ();
}
void
GNUNET_RESOLVER_disconnect ()
{
- GNUNET_assert (NULL == req_head);
- GNUNET_assert (NULL == req_tail);
- if (NULL != client)
+ struct GNUNET_RESOLVER_RequestHandle *rh;
+
+ while (NULL != (rh = req_head))
+ {
+ GNUNET_assert (GNUNET_SYSERR == rh->was_transmitted);
+ GNUNET_CONTAINER_DLL_remove (req_head,
+ req_tail,
+ rh);
+ GNUNET_free (rh);
+ }
+ if (NULL != mq)
{
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Disconnecting from DNS service\n");
- GNUNET_CLIENT_disconnect (client);
- client = NULL;
+ GNUNET_MQ_destroy (mq);
+ mq = NULL;
}
if (NULL != r_task)
{
}
+/**
+ * Task executed on system shutdown.
+ */
+static void
+shutdown_task (void *cls)
+{
+ s_task = NULL;
+ GNUNET_RESOLVER_disconnect ();
+ backoff = GNUNET_TIME_UNIT_MILLISECONDS;
+}
+
+
+/**
+ * Consider disconnecting if we have no further requests pending.
+ */
+static void
+check_disconnect ()
+{
+ struct GNUNET_RESOLVER_RequestHandle *rh;
+
+ for (rh = req_head; NULL != rh; rh = rh->next)
+ if (GNUNET_SYSERR != rh->was_transmitted)
+ return;
+ if (NULL != r_task)
+ {
+ GNUNET_SCHEDULER_cancel (r_task);
+ r_task = NULL;
+ }
+ if (NULL != s_task)
+ return;
+ s_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MILLISECONDS,
+ &shutdown_task,
+ NULL);
+}
+
+
/**
* Convert IP address to string without DNS resolution.
*
*/
static char *
no_resolve (int af,
- const void *ip, socklen_t ip_len)
+ const void *ip,
+ socklen_t ip_len)
{
char buf[INET6_ADDRSTRLEN];
/**
- * Process pending requests to the resolver.
+ * Generic error handler, called with the appropriate error code and
+ * the same closure specified at the creation of the message queue.
+ * Not every message queue implementation supports an error handler.
+ *
+ * @param cls NULL
+ * @param error error code
*/
static void
-process_requests (void);
+mq_error_handler (void *cls,
+ enum GNUNET_MQ_Error error)
+{
+ GNUNET_MQ_destroy (mq);
+ mq = NULL;
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "MQ error, reconnecting\n");
+ reconnect ();
+}
/**
- * Process response with a hostname for a DNS lookup.
- *
- * @param cls our `struct GNUNET_RESOLVER_RequestHandle *` context
- * @param msg message with the hostname, NULL on error
+ * Process pending requests to the resolver.
*/
static void
-handle_response (void *cls,
- const struct GNUNET_MessageHeader *msg)
+process_requests ()
{
- struct GNUNET_RESOLVER_RequestHandle *rh = cls;
- uint16_t size;
- char *nret;
+ struct GNUNET_RESOLVER_GetMessage *msg;
+ struct GNUNET_MQ_Envelope *env;
+ struct GNUNET_RESOLVER_RequestHandle *rh = req_head;
- LOG (GNUNET_ERROR_TYPE_DEBUG,
- "Receiving response from DNS service\n");
- if (NULL == msg)
+ if (NULL == mq)
{
- char buf[INET6_ADDRSTRLEN];
-
- if (NULL != rh->name_callback)
- LOG (GNUNET_ERROR_TYPE_INFO,
- _("Timeout trying to resolve IP address `%s'.\n"),
- inet_ntop (rh->af,
- (const void *) &rh[1],
- buf,
- sizeof(buf)));
- else
- LOG (GNUNET_ERROR_TYPE_INFO,
- _("Timeout trying to resolve hostname `%s'.\n"),
- (const char *) &rh[1]);
- /* check if request was canceled */
- if (GNUNET_SYSERR != rh->was_transmitted)
- {
- if (NULL != rh->name_callback)
- {
- /* no reverse lookup was successful, return IP as string */
- if (GNUNET_NO == rh->received_response)
- {
- nret = no_resolve (rh->af,
- &rh[1],
- rh->data_len);
- rh->name_callback (rh->cls, nret);
- GNUNET_free (nret);
- }
- /* finally, make termination call */
- rh->name_callback (rh->cls,
- NULL);
- }
- if (NULL != rh->addr_callback)
- rh->addr_callback (rh->cls,
- NULL,
- 0);
- }
- rh->was_transmitted = GNUNET_NO;
- GNUNET_RESOLVER_request_cancel (rh);
- GNUNET_CLIENT_disconnect (client);
- client = NULL;
reconnect ();
return;
}
- if (GNUNET_MESSAGE_TYPE_RESOLVER_RESPONSE != ntohs (msg->type))
+ if (NULL == rh)
{
- GNUNET_break (0);
- GNUNET_CLIENT_disconnect (client);
- client = NULL;
- reconnect ();
+ /* nothing to do, release socket really soon if there is nothing
+ * else happening... */
+ s_task =
+ GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MILLISECONDS,
+ &shutdown_task,
+ NULL);
return;
}
+ if (GNUNET_NO != rh->was_transmitted)
+ return; /* waiting for reply */
+ env = GNUNET_MQ_msg_extra (msg,
+ rh->data_len,
+ GNUNET_MESSAGE_TYPE_RESOLVER_REQUEST);
+ msg->direction = htonl (rh->direction);
+ msg->af = htonl (rh->af);
+ GNUNET_memcpy (&msg[1],
+ &rh[1],
+ rh->data_len);
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Transmitting DNS resolution request to DNS service\n");
+ GNUNET_MQ_send (mq,
+ env);
+ rh->was_transmitted = GNUNET_YES;
+}
+
+
+/**
+ * Check validity of response with a hostname for a DNS lookup.
+ *
+ * @param cls NULL
+ * @param msg message with the hostname
+ */
+static int
+check_response (void *cls,
+ const struct GNUNET_MessageHeader *msg)
+{
+ /* implemented in #handle_response() for now */
+ return GNUNET_OK;
+}
+
+
+/**
+ * Check validity of response with a hostname for a DNS lookup.
+ * NOTE: right now rather messy, might want to use different
+ * message types for different response formats in the future.
+ *
+ * @param cls NULL
+ * @param msg message with the response
+ */
+static void
+handle_response (void *cls,
+ const struct GNUNET_MessageHeader *msg)
+{
+ struct GNUNET_RESOLVER_RequestHandle *rh = req_head;
+ uint16_t size;
+ char *nret;
+
size = ntohs (msg->size);
if (size == sizeof (struct GNUNET_MessageHeader))
{
NULL);
rh->was_transmitted = GNUNET_NO;
GNUNET_RESOLVER_request_cancel (rh);
- GNUNET_CLIENT_disconnect (client);
- client = NULL;
+ GNUNET_MQ_destroy (mq);
+ mq = NULL;
reconnect ();
return;
}
0);
rh->was_transmitted = GNUNET_NO;
GNUNET_RESOLVER_request_cancel (rh);
- GNUNET_CLIENT_disconnect (client);
- client = NULL;
+ GNUNET_MQ_destroy (mq);
+ mq = NULL;
reconnect ();
return;
}
sa,
salen);
}
- GNUNET_CLIENT_receive (client,
- &handle_response,
- rh,
- GNUNET_TIME_absolute_get_remaining (rh->timeout));
}
* numeric addresses.
*
* @param cls `struct GNUNET_RESOLVER_RequestHandle` for the request
- * @param tc unused scheduler context
*/
static void
-numeric_resolution (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+numeric_resolution (void *cls)
{
struct GNUNET_RESOLVER_RequestHandle *rh = cls;
struct sockaddr_in v4;
}
if ( ( (rh->af == AF_UNSPEC) ||
(rh->af == AF_INET6) ) &&
- (1 == inet_pton (AF_INET6, hostname, &v6.sin6_addr) ) )
+ (1 == inet_pton (AF_INET6,
+ hostname,
+ &v6.sin6_addr) ) )
{
rh->addr_callback (rh->cls,
(const struct sockaddr *) &v6,
* respective loopback numeric addresses.
*
* @param cls `struct GNUNET_RESOLVER_RequestHandle` for the request
- * @param tc unused scheduler context
*/
static void
-loopback_resolution (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+loopback_resolution (void *cls)
{
struct GNUNET_RESOLVER_RequestHandle *rh = cls;
struct sockaddr_in v4;
rh->addr_callback (rh->cls,
(const struct sockaddr *) &v4,
sizeof (v4));
+
break;
default:
GNUNET_break (0);
rh->addr_callback (rh->cls,
NULL,
0);
- GNUNET_free (rh);
-}
-
-
-/**
- * Task executed on system shutdown.
- */
-static void
-shutdown_task (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
-{
- s_task = NULL;
- GNUNET_RESOLVER_disconnect ();
- backoff = GNUNET_TIME_UNIT_MILLISECONDS;
-}
-
-
-/**
- * Process pending requests to the resolver.
- */
-static void
-process_requests ()
-{
- struct GNUNET_RESOLVER_GetMessage *msg;
- char buf[GNUNET_SERVER_MAX_MESSAGE_SIZE - 1] GNUNET_ALIGN;
- struct GNUNET_RESOLVER_RequestHandle *rh;
-
- if (NULL == client)
- {
- reconnect ();
- return;
- }
- rh = req_head;
- if (NULL == rh)
- {
- /* nothing to do, release socket really soon if there is nothing
- * else happening... */
- s_task =
- GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MILLISECONDS,
- &shutdown_task,
- NULL);
- return;
- }
- if (GNUNET_NO != rh->was_transmitted)
- return; /* waiting for reply */
- msg = (struct GNUNET_RESOLVER_GetMessage *) buf;
- msg->header.size =
- htons (sizeof (struct GNUNET_RESOLVER_GetMessage) + rh->data_len);
- msg->header.type = htons (GNUNET_MESSAGE_TYPE_RESOLVER_REQUEST);
- msg->direction = htonl (rh->direction);
- msg->af = htonl (rh->af);
- memcpy (&msg[1],
- &rh[1],
- rh->data_len);
LOG (GNUNET_ERROR_TYPE_DEBUG,
- "Transmitting DNS resolution request to DNS service\n");
- if (GNUNET_OK !=
- GNUNET_CLIENT_transmit_and_get_response (client,
- &msg->header,
- GNUNET_TIME_absolute_get_remaining (rh->timeout),
- GNUNET_YES,
- &handle_response,
- rh))
- {
- GNUNET_CLIENT_disconnect (client);
- client = NULL;
- GNUNET_break (0);
- reconnect ();
- return;
- }
- rh->was_transmitted = GNUNET_YES;
+ "Finished resolving hostname `%s'.\n",
+ (const char *) &rh[1]);
+ GNUNET_free (rh);
}
* Now try to reconnect to the resolver service.
*
* @param cls NULL
- * @param tc scheduler context
*/
static void
-reconnect_task (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+reconnect_task (void *cls)
{
+ struct GNUNET_MQ_MessageHandler handlers[] = {
+ GNUNET_MQ_hd_var_size (response,
+ GNUNET_MESSAGE_TYPE_RESOLVER_RESPONSE,
+ struct GNUNET_MessageHeader,
+ NULL),
+ GNUNET_MQ_handler_end ()
+ };
+
r_task = NULL;
if (NULL == req_head)
return; /* no work pending */
- if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
- return;
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Trying to connect to DNS service\n");
- client = GNUNET_CLIENT_connect ("resolver",
- resolver_cfg);
- if (NULL == client)
+ mq = GNUNET_CLIENT_connecT (resolver_cfg,
+ "resolver",
+ handlers,
+ &mq_error_handler,
+ NULL);
+ if (NULL == mq)
{
LOG (GNUNET_ERROR_TYPE_DEBUG,
"Failed to connect, will try again later\n");
if (NULL != r_task)
return;
- GNUNET_assert (NULL == client);
+ GNUNET_assert (NULL == mq);
if (NULL != (rh = req_head))
{
switch (rh->was_transmitted)
break;
case GNUNET_SYSERR:
/* request was cancelled, remove entirely */
- GNUNET_CONTAINER_DLL_remove (req_head, req_tail, rh);
+ GNUNET_CONTAINER_DLL_remove (req_head,
+ req_tail,
+ rh);
GNUNET_free (rh);
+ check_disconnect ();
break;
default:
GNUNET_assert (0);
* A DNS resolution timed out. Notify the application.
*
* @param cls the `struct GNUNET_RESOLVER_RequestHandle *`
- * @param tc scheduler context
*/
static void
-handle_lookup_timeout (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+handle_lookup_timeout (void *cls)
{
struct GNUNET_RESOLVER_RequestHandle *rh = cls;
rh->task = NULL;
- rh->addr_callback (rh->cls,
- NULL,
- 0);
+ if (GNUNET_NO == rh->direction)
+ {
+ LOG (GNUNET_ERROR_TYPE_INFO,
+ _("Timeout trying to resolve hostname `%s'.\n"),
+ (const char *) &rh[1]);
+ if (NULL != rh->addr_callback)
+ rh->addr_callback (rh->cls,
+ NULL,
+ 0);
+ }
+ else
+ {
+ char buf[INET6_ADDRSTRLEN];
+
+ LOG (GNUNET_ERROR_TYPE_INFO,
+ _("Timeout trying to resolve IP address `%s'.\n"),
+ inet_ntop (rh->af,
+ (const void *) &rh[1],
+ buf,
+ sizeof(buf)));
+ if (GNUNET_NO == rh->received_response)
+ {
+ char *nret;
+
+ nret = no_resolve (rh->af,
+ &rh[1],
+ rh->data_len);
+ if (NULL != rh->name_callback)
+ rh->name_callback (rh->cls, nret);
+ GNUNET_free (nret);
+ }
+ /* finally, make termination call */
+ if (NULL != rh->name_callback)
+ rh->name_callback (rh->cls,
+ NULL);
+ }
+ rh->was_transmitted = GNUNET_NO;
GNUNET_RESOLVER_request_cancel (rh);
+ process_requests ();
}
GNUNET_break (0);
return NULL;
}
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Trying to resolve hostname `%s'.\n",
+ hostname);
rh = GNUNET_malloc (sizeof (struct GNUNET_RESOLVER_RequestHandle) + slen);
rh->af = af;
rh->addr_callback = callback;
rh->cls = callback_cls;
- memcpy (&rh[1],
- hostname,
- slen);
+ GNUNET_memcpy (&rh[1],
+ hostname,
+ slen);
rh->data_len = slen;
rh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
rh->direction = GNUNET_NO;
rh);
return rh;
}
+ if (GNUNET_OK != check_config ())
+ {
+ GNUNET_free (rh);
+ return NULL;
+ }
rh->task = GNUNET_SCHEDULER_add_delayed (timeout,
&handle_lookup_timeout,
rh);
* conversion and invoke the callback.
*
* @param cls `struct GNUNET_RESOLVER_RequestHandle` for the request
- * @param tc unused scheduler context
*/
static void
-numeric_reverse (void *cls,
- const struct GNUNET_SCHEDULER_TaskContext *tc)
+numeric_reverse (void *cls)
{
struct GNUNET_RESOLVER_RequestHandle *rh = cls;
char *result;
}
rh->name_callback (rh->cls,
NULL);
+ if (NULL != rh->task)
+ {
+ GNUNET_SCHEDULER_cancel (rh->task);
+ rh->task = NULL;
+ }
GNUNET_free (rh);
}
size_t ip_len;
const void *ip;
- check_config ();
+ if (GNUNET_OK != check_config ())
+ {
+ LOG (GNUNET_ERROR_TYPE_ERROR,
+ _("Resolver not configured correctly.\n"));
+ return NULL;
+ }
+
switch (sa->sa_family)
{
case AF_INET:
rh->cls = cls;
rh->af = sa->sa_family;
rh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
- memcpy (&rh[1], ip, ip_len);
+ GNUNET_memcpy (&rh[1],
+ ip,
+ ip_len);
rh->data_len = ip_len;
rh->direction = GNUNET_YES;
rh->received_response = GNUNET_NO;
if (GNUNET_NO == do_resolve)
{
- rh->task = GNUNET_SCHEDULER_add_now (&numeric_reverse, rh);
+ rh->task = GNUNET_SCHEDULER_add_now (&numeric_reverse,
+ rh);
return rh;
}
+ rh->task = GNUNET_SCHEDULER_add_delayed (timeout,
+ &handle_lookup_timeout,
+ rh);
GNUNET_CONTAINER_DLL_insert_tail (req_head,
req_tail,
rh);
void
GNUNET_RESOLVER_request_cancel (struct GNUNET_RESOLVER_RequestHandle *rh)
{
+ if (GNUNET_NO == rh->direction)
+ LOG (GNUNET_ERROR_TYPE_DEBUG,
+ "Asked to cancel request to resolve hostname `%s'.\n",
+ (const char *) &rh[1]);
if (NULL != rh->task)
{
GNUNET_SCHEDULER_cancel (rh->task);
req_tail,
rh);
GNUNET_free (rh);
+ check_disconnect ();
return;
}
GNUNET_assert (GNUNET_YES == rh->was_transmitted);
rh->was_transmitted = GNUNET_SYSERR; /* mark as cancelled */
+ check_disconnect ();
}