Get interface used for routing to given destination

base/networking.c

@@ -762,3 +762,192 @@ ipv6_is_enabled ()
 
   return 1;
 }
+
+gboolean
+ip_islocalhost (struct sockaddr_storage *storage)
+{
+  struct in_addr addr;
+  struct in_addr *addr_p = &addr;
+  struct in6_addr addr6;
+  struct in6_addr *addr6_p = &addr6;
+  struct sockaddr_in *sin_p;
+  struct sockaddr_in6 *sin6_p;
+  struct ifaddrs *ifaddr = NULL;
+  struct ifaddrs *ifa = NULL;
+  int family;
+
+  family = storage->ss_family;
+
+  if (family == AF_INET)
+    {
+      sin_p = (struct sockaddr_in *) storage;
+      addr = sin_p->sin_addr;
+
+      if (addr_p == NULL)
+        return FALSE;
+      /* addr is 0.0.0.0 */
+      if ((addr_p)->s_addr == 0)
+        return TRUE;
+      /* addr starts with 127.0.0.1 */
+      if (((addr_p)->s_addr & htonl (0xFF000000)) == htonl (0x7F000000))
+        return TRUE;
+    }
+  if (family == AF_INET6)
+    {
+      sin6_p = (struct sockaddr_in6 *) storage;
+      addr6 = sin6_p->sin6_addr;
+
+      if (IN6_IS_ADDR_V4MAPPED (&addr6))
+        {
+          /* addr is 0.0.0.0 */
+          if (addr6_p->s6_addr32[3] == 0)
+            return 1;
+
+          /* addr starts with 127.0.0.1 */
+          if ((addr6_p->s6_addr32[3] & htonl (0xFF000000))
+              == htonl (0x7F000000))
+            return 1;
+        }
+      if (IN6_IS_ADDR_LOOPBACK (addr6_p))
+        return 1;
+    }
+
+  if (getifaddrs (&ifaddr) == -1)
+    {
+      g_debug ("%s: getifaddr failed: %s", __func__, strerror (errno));
+      return FALSE;
+    }
+  else
+    {
+      struct sockaddr_in *sin;
+      struct sockaddr_in6 *sin6;
+      for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next)
+        {
+          if (ifa->ifa_addr == NULL)
+            continue;
+          if (ifa->ifa_addr->sa_family == AF_INET)
+            {
+              sin = (struct sockaddr_in *) (ifa->ifa_addr);
+              /* Check if same address as local interface. */
+              if (addr_p->s_addr == sin->sin_addr.s_addr)
+                return TRUE;
+            }
+          if (ifa->ifa_addr->sa_family == AF_INET6)
+            {
+              sin6 = (struct sockaddr_in6 *) (ifa->ifa_addr);
+              /* Check if same address as local interface. */
+              if (IN6_ARE_ADDR_EQUAL (&(sin6->sin6_addr), addr6_p))
+                return TRUE;
+            }
+        }
+      freeifaddrs (ifaddr);
+    }
+
+  return FALSE;
+}
+
+
+struct proc_entry
+{
+  gchar *interface;
+  unsigned long mask;
+  unsigned long dest;
+};
+static GSList *
+get_routes (void)
+{
+  GSList *proc_routes = NULL;
+  GError *err = NULL;
+  GIOChannel *mychannel;
+  gchar *line;
+  gchar **items_in_line;
+  int status;
+  struct proc_entry *entry;
+
+  /* Open "/proc/net/route". */
+  mychannel = g_io_channel_new_file ("/proc/net/route", "r", &err);
+  if (mychannel == NULL)
+    {
+      g_warning ("%s: %s. ", __func__,
+                 err ? err->message : "Error opening /proc/net/ipv6_route");
+      err = NULL;
+      return NULL;
+    }
+
+  /* Skip first first line of file. */
+  status = g_io_channel_read_line (mychannel, &line, NULL, NULL, &err);
+  if (status != G_IO_STATUS_NORMAL || !line || err)
+    {
+      g_warning ("%s: %s", __func__,
+                 err ? err->message
+                     : "g_io_channel_read_line() status != G_IO_STATUS_NORMAL");
+      if (line)
+        g_free (line);
+      err = NULL;
+    }
+
+  /* Until EOF or err we go through lines of file and extract Iface, Mask and
+   * Destination and but it into the to be returned list of routes.*/
+  while (1)
+    {
+      gchar *interface;
+      unsigned long mask;
+      unsigned long dest;
+      gchar *char_p;
+      int count = 0;
+
+      /* get new line */
+      status = g_io_channel_read_line (mychannel, &line, NULL, NULL, &err);
+      if ((status != G_IO_STATUS_NORMAL) || !line || err)
+        {
+          g_warning (
+            "%s: %s", __func__,
+            err ? err->message
+                : "g_io_channel_read_line() status != G_IO_STATUS_NORMAL");
+          err = NULL;
+          if (line)
+            g_free (line);
+          break;
+        }
+
+      /* Get items in line. */
+      items_in_line = g_strsplit (line, "\t", -1);
+      /* Check for missing entries in line of "/proc/net/route". */
+      for (; items_in_line[count]; count++)
+        ;
+      if (11 != count)
+        {
+          g_strfreev (items_in_line);
+          g_free (line);
+          continue;
+        }
+
+      interface = g_strndup (items_in_line[0], 64);
+      /* Cut interface str after ":" if IP aliasing is used. */
+      if ((char_p = strchr (interface, ':')))
+        {
+          *char_p = '\0';
+        }
+      dest = strtoul (items_in_line[1], NULL, 16);
+      mask = strtoul (items_in_line[7], NULL, 16);
+
+      /* Fill GSList entry. */
+      entry = g_malloc0 (sizeof (struct proc_entry));
+      entry->interface = interface;
+      entry->dest = dest;
+      entry->mask = mask;
+      proc_routes = g_slist_append (proc_routes, entry);
+
+      g_strfreev (items_in_line);
+      if (line)
+        g_free (line);
+    }
+
+  status = g_io_channel_shutdown (mychannel, TRUE, &err);
+  if ((G_IO_STATUS_NORMAL != status) || err)
+    g_warning ("%s: %s", __func__,
+               err ? err->message
+                   : "g_io_channel_shutdown() was not successfull");
+
+  return proc_routes;
+}

base/networking_tests.c

@@ -935,12 +935,99 @@ Ensure (networking, port_in_port_ranges)
 
 /* Test suite. */
 
+Ensure (networking, ip_islocalhost)
+{
+  cgreen_mocks_are (loose_mocks);
+
+  /* IPv4 */
+  struct in_addr addr;
+  struct sockaddr_storage storage;
+  struct sockaddr_in sin;
+  memset (&sin, 0, sizeof (struct sockaddr_in));
+  sin.sin_family = AF_INET;
+
+  inet_pton (AF_INET, "127.0.0.1", &(addr.s_addr));
+  sin.sin_addr.s_addr = addr.s_addr;
+  memcpy (&storage, &sin, sizeof (sin));
+  assert_that (ip_islocalhost (&storage), is_true);
+
+  inet_pton (AF_INET, "0.0.0.0", &(addr.s_addr));
+  sin.sin_addr.s_addr = addr.s_addr;
+  memcpy (&storage, &sin, sizeof (sin));
+  assert_that (ip_islocalhost (&storage), is_true);
+
+  inet_pton (AF_INET, "127.100.5.99", &(addr.s_addr));
+  sin.sin_addr.s_addr = addr.s_addr;
+  memcpy (&storage, &sin, sizeof (sin));
+  assert_that (ip_islocalhost (&storage), is_true);
+
+  //!! local interface address
+  // inet_pton (AF_INET, <some local interface address>, &(addr.s_addr));
+  // sin.sin_addr.s_addr = addr.s_addr;
+  // memcpy (&storage, &sin, sizeof (sin));
+  // assert_that (ip_islocalhost (&storage), is_true);
+
+  /* example.com */
+  inet_pton (AF_INET, "93.184.216.34", &(addr.s_addr));
+  sin.sin_addr.s_addr = addr.s_addr;
+  memcpy (&storage, &sin, sizeof (sin));
+  assert_that (ip_islocalhost (&storage), is_false);
+
+  /* IPv6 */
+  struct in6_addr addr_6;
+  struct sockaddr_in6 sin6;
+  memset (&sin, 0, sizeof (struct sockaddr_in6));
+  sin6.sin6_family = AF_INET6;
+
+  inet_pton (AF_INET6, "::FFFF:127.0.0.1", &(addr_6));
+  sin6.sin6_addr = addr_6;
+  memcpy (&storage, &sin6, sizeof (sin6));
+  assert_that (ip_islocalhost (&storage), is_true);
+
+  inet_pton (AF_INET6, "::FFFF:0.0.0.0", &(addr_6));
+  sin6.sin6_addr = addr_6;
+  memcpy (&storage, &sin6, sizeof (sin6));
+  assert_that (ip_islocalhost (&storage), is_true);
+
+  inet_pton (AF_INET6, "::FFFF:127.100.5.99", &(addr_6));
+  sin6.sin6_addr = addr_6;
+  memcpy (&storage, &sin6, sizeof (sin6));
+  assert_that (ip_islocalhost (&storage), is_true);
+
+  /* loopback address */
+  inet_pton (AF_INET6, "0:0:0:0:0:0:0:1", &(addr_6));
+  sin6.sin6_addr = addr_6;
+  memcpy (&storage, &sin6, sizeof (sin6));
+  assert_that (ip_islocalhost (&storage), is_true);
+
+  /* dependent on local environment */
+  // inet_pton (AF_INET6, <some local interface address>, &(addr_6));
+  // sin6.sin6_addr = addr_6;
+  // memcpy (&storage, &sin6, sizeof (sin6));
+  // assert_that (ip_islocalhost (&storage), is_true);
+
+  /* example.com */
+  inet_pton (AF_INET6, "2606:2800:220:1:248:1893:25c8:1946", &(addr_6));
+  sin6.sin6_addr = addr_6;
+  memcpy (&storage, &sin6, sizeof (sin6));
+  assert_that (ip_islocalhost (&storage), is_false);
+}
+
+TestSuite *
+gvm_routethough ()
+{
+  TestSuite *suite = create_test_suite ();
+  add_test_with_context (suite, networking, ip_islocalhost);
+  return suite;
+}
+
 int
 main (int argc, char **argv)
 {
   TestSuite *suite;
 
   suite = create_test_suite ();
+  add_suite (suite, gvm_routethough ());
 
   add_test_with_context (suite, networking, validate_port_range);
   add_test_with_context (suite, networking, port_range_ranges);