--- /dev/null
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vnet/dns/dns.h>
+#include <vlibapi/api.h>
+#include <vlibmemory/api.h>
+
+#include <vlib/vlib.h>
+#include <vnet/vnet.h>
+
+#include <vnet/vnet_msg_enum.h>
+
+#define vl_typedefs /* define message structures */
+#include <vnet/vnet_all_api_h.h>
+#undef vl_typedefs
+
+#define vl_endianfun /* define message structures */
+#include <vnet/vnet_all_api_h.h>
+#undef vl_endianfun
+
+/* instantiate all the print functions we know about */
+#define vl_print(handle, ...) vlib_cli_output (handle, __VA_ARGS__)
+#define vl_printfun
+#include <vnet/vnet_all_api_h.h>
+#undef vl_printfun
+
+#include <vlibapi/api_helper_macros.h>
+
+vlib_node_registration_t dns_resolver_node;
+
+extern int
+vnet_dns_response_to_reply (u8 * response,
+ vl_api_dns_resolve_name_reply_t * rmp,
+ u32 * min_ttlp);
+
+static void
+resolve_event (dns_main_t * dm, f64 now, u8 * reply)
+{
+ vlib_main_t *vm = dm->vlib_main;
+ dns_header_t *d;
+ u32 pool_index;
+ dns_cache_entry_t *ep;
+ u32 min_ttl;
+ u16 flags;
+ u16 rcode;
+ int i;
+ int rv = 0;
+
+ d = (dns_header_t *) reply;
+ flags = clib_net_to_host_u16 (d->flags);
+ rcode = flags & DNS_RCODE_MASK;
+
+ /* $$$ u16 limits cache to 65K entries, fix later multiple dst ports */
+ pool_index = clib_net_to_host_u16 (d->id);
+ dns_cache_lock (dm);
+
+ if (pool_is_free_index (dm->entries, pool_index))
+ {
+ vec_free (reply);
+ vlib_node_increment_counter (vm, dns46_reply_node.index,
+ DNS46_REPLY_ERROR_NO_ELT, 1);
+ dns_cache_unlock (dm);
+ return;
+ }
+
+ ep = pool_elt_at_index (dm->entries, pool_index);
+
+ if (ep->dns_response)
+ vec_free (ep->dns_response);
+
+ /* Handle [sic] recursion AKA CNAME indirection */
+ if (vnet_dns_cname_indirection_nolock (dm, ep, reply))
+ {
+ dns_cache_unlock (dm);
+ return;
+ }
+
+ /* Save the response */
+ ep->dns_response = reply;
+ /* Pick some sensible default. */
+ ep->expiration_time = now + 600.0;
+ if (vec_len (ep->dns_response))
+ ep->flags |= DNS_CACHE_ENTRY_FLAG_VALID;
+
+ /* Most likely, send 1 message */
+ for (i = 0; i < vec_len (ep->api_clients_to_notify); i++)
+ {
+ vl_api_registration_t *regp;
+ vl_api_dns_resolve_name_reply_t *rmp;
+
+ regp = vl_api_client_index_to_registration
+ (ep->api_clients_to_notify[i]);
+
+ if (regp == 0)
+ continue;
+
+ rmp = vl_msg_api_alloc (sizeof (*rmp) + vec_len (ep->dns_response));
+ rmp->_vl_msg_id = clib_host_to_net_u16 (VL_API_DNS_RESOLVE_NAME_REPLY);
+ rmp->context = ep->api_client_contexts[i];
+ min_ttl = ~0;
+ rv = vnet_dns_response_to_reply (ep->dns_response, rmp, &min_ttl);
+ if (min_ttl != ~0)
+ ep->expiration_time = now + min_ttl;
+ rmp->retval = clib_host_to_net_u32 (rv);
+ vl_msg_api_send (regp, (u8 *) rmp);
+ }
+ vec_free (ep->api_clients_to_notify);
+ vec_free (ep->api_client_contexts);
+
+ /* $$$ Add ip4/ip6 reply code */
+
+ for (i = 0; i < vec_len (dm->unresolved_entries); i++)
+ {
+ if (dm->unresolved_entries[i] == pool_index)
+ {
+ vec_delete (dm->unresolved_entries, 1, i);
+ goto found;
+ }
+ }
+ clib_warning ("pool index %d AWOL from unresolved vector", pool_index);
+
+found:
+ /* Deal with bogus names, server issues, etc. */
+ switch (rcode)
+ {
+ default:
+ case DNS_RCODE_NO_ERROR:
+ break;
+
+ case DNS_RCODE_SERVER_FAILURE:
+ case DNS_RCODE_NOT_IMPLEMENTED:
+ case DNS_RCODE_REFUSED:
+ if (ep->server_af == 0)
+ clib_warning ("name server %U backfire",
+ format_ip4_address,
+ dm->ip4_name_servers + ep->server_rotor);
+ else
+ clib_warning ("name server %U backfire",
+ format_ip6_address,
+ dm->ip6_name_servers + ep->server_rotor);
+ /* FALLTHROUGH */
+ case DNS_RCODE_NAME_ERROR:
+ case DNS_RCODE_FORMAT_ERROR:
+ /* remove trash from the cache... */
+ vnet_dns_delete_entry_by_index_nolock (dm, ep - dm->entries);
+ break;
+ }
+
+ dns_cache_unlock (dm);
+ return;
+}
+
+static void
+retry_scan (dns_main_t * dm, f64 now)
+{
+ int i;
+ dns_cache_entry_t *ep;
+
+ for (i = 0; i < vec_len (dm->unresolved_entries); i++)
+ {
+ dns_cache_lock (dm);
+ ep = pool_elt_at_index (dm->entries, dm->unresolved_entries[i]);
+
+ ASSERT ((ep->flags & DNS_CACHE_ENTRY_FLAG_VALID) == 0);
+
+ vnet_send_dns_request (dm, ep);
+ dns_cache_unlock (dm);
+ }
+}
+
+static uword
+dns_resolver_process (vlib_main_t * vm,
+ vlib_node_runtime_t * rt, vlib_frame_t * f)
+{
+ dns_main_t *dm = &dns_main;
+ f64 now;
+ f64 timeout = 1000.0;
+ uword *event_data = 0;
+ uword event_type;
+ int i;
+
+ while (1)
+ {
+ vlib_process_wait_for_event_or_clock (vm, timeout);
+
+ now = vlib_time_now (vm);
+
+ event_type = vlib_process_get_events (vm, (uword **) & event_data);
+
+ switch (event_type)
+ {
+ /* Send one of these when a resolution is pending */
+ case DNS_RESOLVER_EVENT_PENDING:
+ timeout = 2.0;
+ break;
+
+ case DNS_RESOLVER_EVENT_RESOLVED:
+ for (i = 0; i < vec_len (event_data); i++)
+ resolve_event (dm, now, (u8 *) event_data[i]);
+ break;
+
+ case ~0: /* timeout */
+ retry_scan (dm, now);
+ break;
+ }
+ vec_reset_length (event_data);
+
+ /* No work? Back to slow timeout mode... */
+ if (vec_len (dm->unresolved_entries) == 0)
+ timeout = 1000.0;
+ }
+ return 0; /* or not */
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (dns_resolver_node) =
+{
+ .function = dns_resolver_process,
+ .type = VLIB_NODE_TYPE_PROCESS,
+ .name = "dns-resolver-process",
+};
+/* *INDENT-ON* */
+
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
Code Review / vpp.git / blobdiff