[GNUnet-SVN] r18982 - gnunet/src/dns

[gnunet]

Author: grothoff
Date: 2012-01-04 15:20:36 +0100 (Wed, 04 Jan 2012)
New Revision: 18982

Added:
   gnunet/src/dns/gnunet-dns-monitor.c
Modified:
   gnunet/src/dns/dnsparser.c
   gnunet/src/dns/gnunet-service-dns_new.c
Log:
adding missing file

Modified: gnunet/src/dns/dnsparser.c
===================================================================
--- gnunet/src/dns/dnsparser.c  2012-01-04 12:36:43 UTC (rev 18981)
+++ gnunet/src/dns/dnsparser.c  2012-01-04 14:20:36 UTC (rev 18982)
@@ -86,7 +86,10 @@
       goto error;
     len = input[*off];
     if (0 == len)
+    {
+      (*off)++;
       break;
+    }
     if (len < 64)
     {
       if (*off + 1 + len > udp_payload_length)

Added: gnunet/src/dns/gnunet-dns-monitor.c
===================================================================
--- gnunet/src/dns/gnunet-dns-monitor.c                         (rev 0)
+++ gnunet/src/dns/gnunet-dns-monitor.c 2012-01-04 14:20:36 UTC (rev 18982)
@@ -0,0 +1,300 @@
+/*
+     This file is part of GNUnet.
+     (C) 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
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     GNUnet is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file src/dns/gnunet-dns-monitor.c
+ * @brief Tool to monitor DNS queries
+ * @author Christian Grothoff
+ */
+
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_dns_service-new.h"
+#include "gnunet_dnsparser_lib.h"
+
+/**
+ * Handle to transport service.
+ */
+static struct GNUNET_DNS_Handle *handle;
+
+/**
+ * Option -s.
+ */
+static int benchmark_send;
+
+/**
+ * Global return value (0 success).
+ */
+static int ret;
+
+/**
+ * Selected level of verbosity.
+ */
+static int verbosity;
+
+
+/**
+ * Convert numeric DNS record type to a string.
+ *
+ * @param type type to convert
+ * @return type as string, only valid until the next call to this function
+ */
+static const char *
+get_type (uint16_t type)
+{
+  static char buf[6];
+  switch (type)
+  {
+  case GNUNET_DNSPARSER_TYPE_A: return "A";
+  case GNUNET_DNSPARSER_TYPE_NS: return "NS";
+  case GNUNET_DNSPARSER_TYPE_CNAME: return "CNAME";
+  case GNUNET_DNSPARSER_TYPE_SOA: return "SOA";
+  case GNUNET_DNSPARSER_TYPE_PTR: return "PTR";
+  case GNUNET_DNSPARSER_TYPE_MX: return "MX";
+  case GNUNET_DNSPARSER_TYPE_TXT: return "TXT";
+  case GNUNET_DNSPARSER_TYPE_AAAA: return "AAAA";
+  case GNUNET_DNSPARSER_TYPE_IXFR: return "IXFR";
+  case GNUNET_DNSPARSER_TYPE_AXFR: return "AXFR";
+  }
+  GNUNET_snprintf (buf, sizeof (buf), "%u", (unsigned int) type);
+  return buf;
+}
+
+
+/**
+ * Convert numeric DNS record class to a string.
+ *
+ * @param class class to convert
+ * @return class as string, only valid until the next call to this function
+ */
+static const char *
+get_class (uint16_t class)
+{
+  static char buf[6];
+  switch (class)
+  {
+  case GNUNET_DNSPARSER_CLASS_INTERNET: return "IN";
+  case GNUNET_DNSPARSER_CLASS_CHAOS: return "CHAOS";
+  case GNUNET_DNSPARSER_CLASS_HESIOD: return "HESIOD";
+  }
+  GNUNET_snprintf (buf, sizeof (buf), "%u", (unsigned int) class);
+  return buf;
+}
+
+
+/**
+ * Output the given DNS query to stdout.
+ *
+ * @param query query to display.
+ */
+static void
+display_query (const struct GNUNET_DNSPARSER_Query *query)
+{
+  fprintf (stdout,
+          "\t\t%s %s: %s\n",
+          get_class (query->class),
+          get_type (query->type),
+          query->name);
+}
+
+
+/**
+ * Output the given DNS query to stdout.
+ *
+ * @param query query to display.
+ */
+static void
+display_record (const struct GNUNET_DNSPARSER_Record *record)
+{
+  const char *format;
+  char buf[INET6_ADDRSTRLEN];
+  char *tmp;
+  
+  tmp = NULL;
+  switch (record->type)
+  {
+  case GNUNET_DNSPARSER_TYPE_A:
+    if (record->data_len != sizeof (struct in_addr))
+      format = "<invalid>";
+    else
+      format = inet_ntop (AF_INET, record->data, buf, sizeof (buf));
+    break;
+  case GNUNET_DNSPARSER_TYPE_AAAA:
+    if (record->data_len != sizeof (struct in6_addr))
+      format = "<invalid>";
+    else
+      format = inet_ntop (AF_INET6, record->data, buf, sizeof (buf));
+    break;
+  case GNUNET_DNSPARSER_TYPE_CNAME:
+    tmp = GNUNET_strdup ("FIXME");
+  default:
+    format = "<payload>";
+    break;
+  }
+  fprintf (stdout,
+          "\t\t%s %s: %s = %s (%u bytes, %u s)\n",
+          get_class (record->class),
+          get_type (record->type),
+          record->name,
+          format,
+          (unsigned int) record->data_len,
+          (unsigned int) (GNUNET_TIME_absolute_get_remaining 
(record->expiration_time).rel_value / 1000));
+  GNUNET_free_non_null (tmp);
+}
+
+
+/**
+ * Signature of a function that is called whenever the DNS service
+ * encounters a DNS request and needs to do something with it.  The
+ * function has then the chance to generate or modify the response by
+ * calling one of the three "GNUNET_DNS_request_*" continuations.
+ *
+ * When a request is intercepted, this function is called first to
+ * give the client a chance to do the complete address resolution;
+ * "rdata" will be NULL for this first call for a DNS request, unless
+ * some other client has already filled in a response.
+ *
+ * If multiple clients exist, all of them are called before the global
+ * DNS.  The global DNS is only called if all of the clients'
+ * functions call GNUNET_DNS_request_forward.  Functions that call
+ * GNUNET_DNS_request_forward will be called again before a final
+ * response is returned to the application.  If any of the clients'
+ * functions call GNUNET_DNS_request_drop, the response is dropped.
+ *
+ * @param cls closure
+ * @param rh request handle to user for reply
+ * @param request_length number of bytes in request
+ * @param request udp payload of the DNS request
+ */
+static void 
+display_request (void *cls,
+                struct GNUNET_DNS_RequestHandle *rh,
+                size_t request_length,
+                const char *request)
+{
+  static const char *return_codes[] =
+    {
+      "No error", "Format error", "Server failure", "Name error",
+      "Not implemented", "Refused", "YXDomain", "YXRRset",
+      "NXRRset", "NOT AUTH", "NOT ZONE", "<invalid>",
+      "<invalid>", "<invalid>", "<invalid>", "<invalid>"
+    };
+  static const char *op_codes[] =
+    {
+      "Query", "Inverse query", "Status", "<invalid>",
+      "<invalid>", "<invalid>", "<invalid>", "<invalid>",
+      "<invalid>", "<invalid>", "<invalid>", "<invalid>",
+      "<invalid>", "<invalid>", "<invalid>", "<invalid>"
+    };
+  struct GNUNET_DNSPARSER_Packet *p;
+  unsigned int i;
+
+  p = GNUNET_DNSPARSER_parse (request, request_length);
+  if (NULL == p)
+  {
+    fprintf (stderr, "Received malformed DNS packet!\n");
+    // FIXME: drop instead?
+    GNUNET_DNS_request_forward (rh);
+    return;
+  }
+  fprintf (stdout,
+          "%s with ID: %5u Flags: %s%s%s%s%s%s Return Code: %s Opcode: %s\n",
+          p->flags.query_or_response ? "Response" : "Query",
+          p->id,
+          p->flags.recursion_desired ? "RD " : "",
+          p->flags.message_truncated ? "MT " : "",
+          p->flags.authoritative_answer ? "AA " : "",
+          p->flags.checking_disabled ? "CD " : "",
+          p->flags.authenticated_data ? "AD " : "",
+          p->flags.recursion_available ? "RA " : "",
+          return_codes[p->flags.return_code & 15],
+          op_codes[p->flags.opcode & 15]);  
+  if (p->num_queries > 0)
+    fprintf (stdout,
+            "\tQueries:\n");
+  for (i=0;i<p->num_queries;i++)
+    display_query (&p->queries[i]);
+  
+  if (p->num_answers > 0)
+    fprintf (stdout,
+            "\tAnswers:\n");
+  for (i=0;i<p->num_answers;i++)
+    display_record (&p->answers[i]);
+  fprintf (stdout, "\n");
+  GNUNET_DNSPARSER_free_packet (p);
+  GNUNET_DNS_request_forward (rh);
+}
+
+
+/**
+ * Shutdown.
+ */
+static void
+do_disconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  if (NULL != handle)
+  {
+    GNUNET_DNS_disconnect (handle);
+    handle = NULL;
+  }
+}
+
+
+/**
+ * Main function that will be run by the scheduler.
+ *
+ * @param cls closure
+ * @param args remaining command-line arguments
+ * @param cfgfile name of the configuration file used (for saving, can be 
NULL!)
+ * @param cfg configuration
+ */
+static void
+run (void *cls, char *const *args, const char *cfgfile,
+     const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+  handle =
+    GNUNET_DNS_connect (cfg, 
+                       GNUNET_DNS_FLAG_REQUEST_MONITOR | 
GNUNET_DNS_FLAG_RESPONSE_MONITOR,
+                       &display_request,
+                       NULL);
+  GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
+                               &do_disconnect, NULL);
+}
+
+
+int
+main (int argc, char *const *argv)
+{
+  static const struct GNUNET_GETOPT_CommandLineOption options[] = {
+    {'s', "testoption", NULL,
+     gettext_noop ("not useful"),
+     0, &GNUNET_GETOPT_set_one, &benchmark_send},
+    GNUNET_GETOPT_OPTION_VERBOSE (&verbosity),
+    GNUNET_GETOPT_OPTION_END
+  };
+  return (GNUNET_OK ==
+          GNUNET_PROGRAM_run (argc, argv, "gnunet-dns-monitor",
+                              gettext_noop
+                              ("Monitor DNS queries."), options,
+                              &run, NULL)) ? ret : 1;
+}
+
+
+/* end of gnunet-dns-monitor.c */

Modified: gnunet/src/dns/gnunet-service-dns_new.c
===================================================================
--- gnunet/src/dns/gnunet-service-dns_new.c     2012-01-04 12:36:43 UTC (rev 
18981)
+++ gnunet/src/dns/gnunet-service-dns_new.c     2012-01-04 14:20:36 UTC (rev 
18982)
@@ -131,7 +131,7 @@
    * Showing the request to all monitor clients.  If
    * client list is empty, will enter QUERY phase.
    */
-  RP_MONITOR,
+  RP_REQUEST_MONITOR,
 
   /**
    * Showing the request to PRE-RESOLUTION clients to find an answer.
@@ -147,11 +147,17 @@
   /**
    * Client (or global DNS request) has resulted in a response.
    * Forward to all POST-RESOLUTION clients.  If client list is empty,
-   * give the result to the hijacker (and be done).
+   * will enter RESPONSE_MONITOR phase.
    */
   RP_MODIFY,
 
   /**
+   * Showing the request to all monitor clients.  If
+   * client list is empty, give the result to the hijacker (and be done).
+   */
+  RP_RESPONSE_MONITOR,
+
+  /**
    * Some client has told us to drop the request.
    */
   RP_DROP
@@ -384,7 +390,7 @@
   GNUNET_array_grow (rr->client_wait_list,
                     rr->client_wait_list_length,
                     0); 
-  if (RP_MODIFY != rr->phase)
+  if (RP_RESPONSE_MONITOR != rr->phase)
   {
     /* no response, drop */
     cleanup_rr (rr);
@@ -632,7 +638,7 @@
   switch (rr->phase)
   {
   case RP_INIT:
-    rr->phase = RP_MONITOR;
+    rr->phase = RP_REQUEST_MONITOR;
     for (cr = clients_head; NULL != cr; cr = cr->next)
     {
       if (0 != (cr->flags & GNUNET_DNS_FLAG_REQUEST_MONITOR))
@@ -642,7 +648,7 @@
     }
     next_phase (rr);
     return;
-  case RP_MONITOR:
+  case RP_REQUEST_MONITOR:
     rr->phase = RP_QUERY;
     for (cr = clients_head; NULL != cr; cr = cr->next)
     {
@@ -694,6 +700,17 @@
     next_phase (rr);
     return;
   case RP_MODIFY:
+    rr->phase = RP_RESPONSE_MONITOR;
+    for (cr = clients_head; NULL != cr; cr = cr->next)
+    {
+      if (0 != (cr->flags & GNUNET_DNS_FLAG_RESPONSE_MONITOR))
+       GNUNET_array_append (rr->client_wait_list,
+                            rr->client_wait_list_length,
+                            cr);
+    }
+    next_phase (rr);
+    return;
+ case RP_RESPONSE_MONITOR:
     request_done (rr);
     break;
   case RP_DROP:
@@ -1019,6 +1036,8 @@
   }
   for (i=0;i<rr->client_wait_list_length;i++)
   {
+    if (NULL == rr->client_wait_list[i])
+      continue;
     if (rr->client_wait_list[i]->client != client)
       continue;
     rr->client_wait_list[i] = NULL;
@@ -1032,7 +1051,8 @@
     case 2: /* update */
       msize -= sizeof (struct GNUNET_DNS_Response);
       if ( (sizeof (struct dns_header) > msize) ||
-          (RP_MONITOR == rr->phase) )
+          (RP_REQUEST_MONITOR == rr->phase) ||
+          (RP_RESPONSE_MONITOR == rr->phase) )
       {
        GNUNET_break (0);
        GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);