diff options
Diffstat (limited to 'src/vnet/dns/resolver_process.c')
| -rw-r--r-- | src/vnet/dns/resolver_process.c | 378 |
1 files changed, 0 insertions, 378 deletions
diff --git a/src/vnet/dns/resolver_process.c b/src/vnet/dns/resolver_process.c deleted file mode 100644 index 4ed7c799ce2..00000000000 --- a/src/vnet/dns/resolver_process.c +++ /dev/null @@ -1,378 +0,0 @@ -/* - * 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> - -extern int -vnet_dns_response_to_reply (u8 * response, - vl_api_dns_resolve_name_reply_t * rmp, - u32 * min_ttlp); -extern int -vnet_dns_response_to_name (u8 * response, - vl_api_dns_resolve_ip_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_pending_request_t *pr; - dns_header_t *d; - u32 pool_index; - dns_cache_entry_t *ep; - u32 min_ttl; - u16 flags; - u16 rcode; - int i; - int entry_was_valid; - int remove_count; - 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); - if (0) - clib_warning ("pool index %d is free", pool_index); - 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 */ - rv = vnet_dns_cname_indirection_nolock (dm, pool_index, reply); - - /* CNAME found, further resolution pending, we're done here */ - if (rv > 0) - { - dns_cache_unlock (dm); - return; - } - /* Server backfire: refused to answer, or sent zero replies */ - if (rv < 0) - { - /* Try a different server */ - if (ep->server_af /* ip6 */ ) - { - if (0) - clib_warning ("Server %U failed to resolve '%s'", - format_ip6_address, - dm->ip6_name_servers + ep->server_rotor, ep->name); - /* Any more servers to try? */ - if (ep->server_fails > 1 || vec_len (dm->ip6_name_servers) <= 1) - { - /* No, tell the client to go away */ - goto reply; - } - ep->retry_count = 0; - ep->server_rotor++; - ep->server_fails++; - if (ep->server_rotor >= vec_len (dm->ip6_name_servers)) - ep->server_rotor = 0; - if (0) - clib_warning ("Try server %U", format_ip6_address, - dm->ip6_name_servers + ep->server_rotor); - vnet_dns_send_dns6_request - (dm, ep, dm->ip6_name_servers + ep->server_rotor); - } - else - { - if (0) - clib_warning ("Server %U failed to resolve '%s'", - format_ip4_address, - dm->ip4_name_servers + ep->server_rotor, ep->name); - - if (ep->server_fails > 1 || vec_len (dm->ip4_name_servers) <= 1) - { - /* No, tell the client to go away */ - goto reply; - } - ep->retry_count = 0; - ep->server_rotor++; - ep->server_fails++; - if (ep->server_rotor >= vec_len (dm->ip4_name_servers)) - ep->server_rotor = 0; - if (0) - clib_warning ("Try server %U", format_ip4_address, - dm->ip4_name_servers + ep->server_rotor); - vnet_dns_send_dns4_request - (dm, ep, dm->ip4_name_servers + ep->server_rotor); - } - dns_cache_unlock (dm); - return; - } - -reply: - /* Save the response */ - ep->dns_response = reply; - - /* - * Pick a sensible default cache entry expiration time. - * We don't play the 10-second timeout game. - */ - ep->expiration_time = now + 600.0; - - if (0) - clib_warning ("resolving '%s', was %s valid", - ep->name, (ep->flags & DNS_CACHE_ENTRY_FLAG_VALID) ? - "already" : "not"); - /* - * The world is a mess. A single DNS request sent to e.g. 8.8.8.8 - * may yield multiple, subtly different responses - all with the same - * DNS protocol-level ID. - * - * Last response wins in terms of what ends up in the cache. - * First response wins in terms of the response sent to the client. - */ - - /* Strong hint that we may not find a pending resolution entry */ - entry_was_valid = (ep->flags & DNS_CACHE_ENTRY_FLAG_VALID) ? 1 : 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->pending_requests); i++) - { - vl_api_registration_t *regp; - - pr = vec_elt_at_index (ep->pending_requests, i); - - switch (pr->request_type) - { - case DNS_API_PENDING_NAME_TO_IP: - { - vl_api_dns_resolve_name_reply_t *rmp; - regp = vl_api_client_index_to_registration (pr->client_index); - if (regp == 0) - continue; - - rmp = vl_msg_api_alloc (sizeof (*rmp)); - rmp->_vl_msg_id = - clib_host_to_net_u16 (VL_API_DNS_RESOLVE_NAME_REPLY); - rmp->context = pr->client_context; - 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_api_send_msg (regp, (u8 *) rmp); - } - break; - - case DNS_API_PENDING_IP_TO_NAME: - { - vl_api_dns_resolve_ip_reply_t *rmp; - - regp = vl_api_client_index_to_registration (pr->client_index); - if (regp == 0) - continue; - - rmp = vl_msg_api_alloc (sizeof (*rmp)); - rmp->_vl_msg_id = - clib_host_to_net_u16 (VL_API_DNS_RESOLVE_IP_REPLY); - rmp->context = pr->client_context; - min_ttl = ~0; - rv = vnet_dns_response_to_name (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_api_send_msg (regp, (u8 *) rmp); - } - break; - - case DNS_PEER_PENDING_IP_TO_NAME: - case DNS_PEER_PENDING_NAME_TO_IP: - if (pr->is_ip6) - vnet_send_dns6_reply (dm, pr, ep, 0 /* allocate a buffer */ ); - else - vnet_send_dns4_reply (dm, pr, ep, 0 /* allocate a buffer */ ); - break; - default: - clib_warning ("request type %d unknown", pr->request_type); - break; - } - } - vec_free (ep->pending_requests); - - remove_count = 0; - for (i = 0; i < vec_len (dm->unresolved_entries); i++) - { - if (dm->unresolved_entries[i] == pool_index) - { - vec_delete (dm->unresolved_entries, 1, i); - remove_count++; - i--; - } - } - /* See multiple response comment above... */ - if (remove_count == 0) - { - u32 error_code = entry_was_valid ? DNS46_REPLY_ERROR_MULTIPLE_REPLY : - DNS46_REPLY_ERROR_NO_UNRESOLVED_ENTRY; - - vlib_node_increment_counter (vm, dns46_reply_node.index, error_code, 1); - dns_cache_unlock (dm); - return; - } - - /* 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 can't resolve '%s'", - format_ip4_address, - dm->ip4_name_servers + ep->server_rotor, ep->name); - else - clib_warning ("name server %U can't resolve '%s'", - format_ip6_address, - dm->ip6_name_servers + ep->server_rotor, ep->name); - /* 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 */ -} - -void -vnet_dns_create_resolver_process (dns_main_t * dm) -{ - /* Already created the resolver process? */ - if (dm->resolver_process_node_index > 0) - return; - - /* No, create it now and make a note of the node index */ - dm->resolver_process_node_index = vlib_process_create - (dm->vlib_main, "dns-resolver-process", - dns_resolver_process, 16 /* log2_n_stack_bytes */ ); -} - -/* - * fd.io coding-style-patch-verification: ON - * - * Local Variables: - * eval: (c-set-style "gnu") - * End: - */ |