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gerrit.nordix.org / fdio / vpp / b9f2cf0bff89ccf5c88072213a25efb65fb5516e / . / src / vnet / dns / dns.c
blob: 9facb9b564056bca8e22efd6dabde2fb1b1503fd [file] [log] [blame]
/*
* 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 <vnet/vnet.h>
#include <vnet/fib/fib.h>
#include <vlibmemory/api.h>
#include <vnet/udp/udp.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>
dns_main_t dns_main;
static int
dns_cache_clear (dns_main_t * dm)
{
dns_cache_entry_t *ep;
if (dm->is_enabled == 0)
return VNET_API_ERROR_NAME_RESOLUTION_NOT_ENABLED;
dns_cache_lock (dm);
/* *INDENT-OFF* */
pool_foreach (ep, dm->entries,
({
vec_free (ep->name);
vec_free (ep->api_clients_to_notify);
vec_free (ep->api_client_contexts);
vec_free (ep->ip4_peers_to_notify);
vec_free (ep->ip6_peers_to_notify);
}));
/* *INDENT-ON* */
pool_free (dm->entries);
hash_free (dm->cache_entry_by_name);
dm->cache_entry_by_name = hash_create_string (0, sizeof (uword));
vec_free (dm->unresolved_entries);
dns_cache_unlock (dm);
return 0;
}
static int
dns_enable_disable (dns_main_t * dm, int is_enable)
{
vlib_thread_main_t *tm = &vlib_thread_main;
u32 n_vlib_mains = tm->n_vlib_mains;
if (is_enable)
{
if (vec_len (dm->ip4_name_servers) == 0
&& (vec_len (dm->ip6_name_servers) == 0))
return VNET_API_ERROR_NO_NAME_SERVERS;
if (dm->cache_entry_by_name == 0)
{
if (n_vlib_mains > 1)
dm->cache_lock = clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES,
CLIB_CACHE_LINE_BYTES);
dm->cache_entry_by_name = hash_create_string (0, sizeof (uword));
}
dm->is_enabled = 1;
}
else
{
dns_cache_clear (dm);
dm->is_enabled = 0;
}
return 0;
}
static void vl_api_dns_enable_disable_t_handler
(vl_api_dns_enable_disable_t * mp)
{
vl_api_dns_enable_disable_reply_t *rmp;
dns_main_t *dm = &dns_main;
int rv;
rv = dns_enable_disable (dm, mp->enable);
REPLY_MACRO (VL_API_DNS_ENABLE_DISABLE_REPLY);
}
static int
dns6_name_server_add_del (dns_main_t * dm,
u8 * server_address_as_u8, int is_add)
{
int i;
ip6_address_t *ap;
if (is_add)
{
/* Already there? done... */
for (i = 0; i < vec_len (dm->ip6_name_servers); i++)
{
if (!memcmp (dm->ip6_name_servers + i, server_address_as_u8,
sizeof (ip6_address_t)))
return 0;
}
vec_add2 (dm->ip6_name_servers, ap, 1);
clib_memcpy (ap, server_address_as_u8, sizeof (*ap));
}
else
{
for (i = 0; i < vec_len (dm->ip6_name_servers); i++)
{
if (!memcmp (dm->ip6_name_servers + i, server_address_as_u8,
sizeof (ip6_address_t)))
{
vec_delete (dm->ip6_name_servers, 1, i);
return 0;
}
}
return VNET_API_ERROR_NAME_SERVER_NOT_FOUND;
}
return 0;
}
static int
dns4_name_server_add_del (dns_main_t * dm,
u8 * server_address_as_u8, int is_add)
{
int i;
ip4_address_t *ap;
if (is_add)
{
/* Already there? done... */
for (i = 0; i < vec_len (dm->ip4_name_servers); i++)
{
if (!memcmp (dm->ip4_name_servers + i, server_address_as_u8,
sizeof (ip4_address_t)))
return 0;
}
vec_add2 (dm->ip4_name_servers, ap, 1);
clib_memcpy (ap, server_address_as_u8, sizeof (*ap));
}
else
{
for (i = 0; i < vec_len (dm->ip4_name_servers); i++)
{
if (!memcmp (dm->ip4_name_servers + i, server_address_as_u8,
sizeof (ip4_address_t)))
{
vec_delete (dm->ip4_name_servers, 1, i);
return 0;
}
}
return VNET_API_ERROR_NAME_SERVER_NOT_FOUND;
}
return 0;
}
static void vl_api_dns_name_server_add_del_t_handler
(vl_api_dns_name_server_add_del_t * mp)
{
dns_main_t *dm = &dns_main;
vl_api_dns_name_server_add_del_reply_t *rmp;
int rv;
if (mp->is_ip6)
rv = dns6_name_server_add_del (dm, mp->server_address, mp->is_add);
else
rv = dns4_name_server_add_del (dm, mp->server_address, mp->is_add);
REPLY_MACRO (VL_API_DNS_NAME_SERVER_ADD_DEL_REPLY);
}
static void
send_dns4_request (dns_main_t * dm,
dns_cache_entry_t * ep, ip4_address_t * server)
{
vlib_main_t *vm = dm->vlib_main;
f64 now = vlib_time_now (vm);
u32 bi;
vlib_buffer_t *b;
ip4_header_t *ip;
fib_prefix_t prefix;
fib_node_index_t fei;
u32 sw_if_index, fib_index;
udp_header_t *udp;
ip4_main_t *im4 = &ip4_main;
ip_lookup_main_t *lm4 = &im4->lookup_main;
ip_interface_address_t *ia = 0;
ip4_address_t *src_address;
u8 *dns_request;
vlib_frame_t *f;
u32 *to_next;
ASSERT (ep->dns_request);
/* Find a FIB path to the server */
clib_memcpy (&prefix.fp_addr.ip4, server, sizeof (*server));
prefix.fp_proto = FIB_PROTOCOL_IP4;
prefix.fp_len = 32;
fib_index = fib_table_find (prefix.fp_proto, 0 /* default VRF for now */ );
if (fib_index == (u32) ~ 0)
{
clib_warning ("no fib table");
return;
}
fei = fib_table_lookup (fib_index, &prefix);
/* Couldn't find route to destination. Bail out. */
if (fei == FIB_NODE_INDEX_INVALID)
{
clib_warning ("no route to DNS server");
return;
}
sw_if_index = fib_entry_get_resolving_interface (fei);
if (sw_if_index == ~0)
{
clib_warning
("route to %U exists, fei %d, get_resolving_interface returned"
" ~0", fei, format_ip4_address, &prefix.fp_addr);
return;
}
/* *INDENT-OFF* */
foreach_ip_interface_address(lm4, ia, sw_if_index, 1 /* honor unnummbered */,
({
src_address = ip_interface_address_get_address (lm4, ia);
goto found_src_address;
}));
/* *INDENT-ON* */
clib_warning ("FIB BUG");
return;
found_src_address:
/* Go get a buffer */
if (vlib_buffer_alloc (dm->vlib_main, &bi, 1) != 1)
return;
b = vlib_get_buffer (vm, bi);
b->current_length = sizeof (ip4_header_t) + sizeof (udp_header_t) +
vec_len (ep->dns_request);
b->total_length_not_including_first_buffer = 0;
b->flags =
VLIB_BUFFER_TOTAL_LENGTH_VALID | VNET_BUFFER_F_LOCALLY_ORIGINATED;
vnet_buffer (b)->sw_if_index[VLIB_RX] = 0; /* "local0" */
vnet_buffer (b)->sw_if_index[VLIB_TX] = 0; /* default VRF for now */
ip = vlib_buffer_get_current (b);
memset (ip, 0, sizeof (*ip));
udp = (udp_header_t *) (ip + 1);
memset (udp, 0, sizeof (*udp));
dns_request = (u8 *) (udp + 1);
/* IP header */
ip->ip_version_and_header_length = 0x45;
ip->length = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b));
ip->ttl = 255;
ip->protocol = IP_PROTOCOL_UDP;
ip->src_address.as_u32 = src_address->as_u32;
ip->dst_address.as_u32 = server->as_u32;
ip->checksum = ip4_header_checksum (ip);
/* UDP header */
udp->src_port = clib_host_to_net_u16 (UDP_DST_PORT_dns_reply);
udp->dst_port = clib_host_to_net_u16 (UDP_DST_PORT_dns);
udp->length = clib_host_to_net_u16 (sizeof (udp_header_t) +
vec_len (ep->dns_request));
udp->checksum = 0;
/* The actual DNS request */
clib_memcpy (dns_request, ep->dns_request, vec_len (ep->dns_request));
/* Ship it to ip4_lookup */
f = vlib_get_frame_to_node (vm, ip4_lookup_node.index);
to_next = vlib_frame_vector_args (f);
to_next[0] = bi;
f->n_vectors = 1;
vlib_put_frame_to_node (vm, ip4_lookup_node.index, f);
ep->retry_timer = now + 2.0;
}
static void
send_dns6_request (dns_main_t * dm,
dns_cache_entry_t * ep, ip6_address_t * server)
{
vlib_main_t *vm = dm->vlib_main;
f64 now = vlib_time_now (vm);
u32 bi;
vlib_buffer_t *b;
ip6_header_t *ip;
fib_prefix_t prefix;
fib_node_index_t fei;
u32 sw_if_index, fib_index;
udp_header_t *udp;
ip6_main_t *im6 = &ip6_main;
ip_lookup_main_t *lm6 = &im6->lookup_main;
ip_interface_address_t *ia = 0;
ip6_address_t *src_address;
u8 *dns_request;
vlib_frame_t *f;
u32 *to_next;
int junk __attribute__ ((unused));
ASSERT (ep->dns_request);
/* Find a FIB path to the server */
clib_memcpy (&prefix.fp_addr, server, sizeof (*server));
prefix.fp_proto = FIB_PROTOCOL_IP6;
prefix.fp_len = 32;
fib_index = fib_table_find (prefix.fp_proto, 0 /* default VRF for now */ );
if (fib_index == (u32) ~ 0)
{
clib_warning ("no fib table");
return;
}
fei = fib_table_lookup (fib_index, &prefix);
/* Couldn't find route to destination. Bail out. */
if (fei == FIB_NODE_INDEX_INVALID)
{
clib_warning ("no route to DNS server");
}
sw_if_index = fib_entry_get_resolving_interface (fei);
/* *INDENT-OFF* */
foreach_ip_interface_address(lm6, ia, sw_if_index, 1 /* honor unnummbered */,
({
src_address = ip_interface_address_get_address (lm6, ia);
goto found_src_address;
}));
/* *INDENT-ON* */
clib_warning ("FIB BUG");
return;
found_src_address:
/* Go get a buffer */
if (vlib_buffer_alloc (dm->vlib_main, &bi, 1) != 1)
return;
b = vlib_get_buffer (vm, bi);
b->current_length = sizeof (ip6_header_t) + sizeof (udp_header_t) +
vec_len (ep->dns_request);
b->total_length_not_including_first_buffer = 0;
b->flags =
VLIB_BUFFER_TOTAL_LENGTH_VALID | VNET_BUFFER_F_LOCALLY_ORIGINATED;
ip = vlib_buffer_get_current (b);
memset (ip, 0, sizeof (*ip));
udp = (udp_header_t *) (ip + 1);
memset (udp, 0, sizeof (*udp));
dns_request = (u8 *) (udp + 1);
/* IP header */
ip->ip_version_traffic_class_and_flow_label =
clib_host_to_net_u32 (0x6 << 28);
ip->payload_length =
clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b)
- sizeof (ip6_header_t));
ip->hop_limit = 255;
ip->protocol = IP_PROTOCOL_UDP;
clib_memcpy (&ip->src_address, src_address, sizeof (ip6_address_t));
clib_memcpy (&ip->dst_address, server, sizeof (ip6_address_t));
/* UDP header */
udp->src_port = clib_host_to_net_u16 (UDP_DST_PORT_dns_reply);
udp->dst_port = clib_host_to_net_u16 (UDP_DST_PORT_dns);
udp->length = clib_host_to_net_u16 (sizeof (udp_header_t) +
vec_len (ep->dns_request));
udp->checksum = 0;
udp->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ip, &junk);
/* The actual DNS request */
clib_memcpy (dns_request, ep->dns_request, vec_len (ep->dns_request));
/* Ship it to ip6_lookup */
f = vlib_get_frame_to_node (vm, ip6_lookup_node.index);
to_next = vlib_frame_vector_args (f);
to_next[0] = bi;
f->n_vectors = 1;
ep->retry_timer = now + 2.0;
}
/**
* Translate "foo.com" into "0x3 f o o 0x3 c o m 0x0"
* A historical / hysterical micro-TLV scheme. DGMS.
*/
u8 *
name_to_labels (u8 * name)
{
int i;
int last_label_index;
u8 *rv;
rv = vec_dup (name);
/* punch in space for the first length */
vec_insert (rv, 1, 0);
last_label_index = 0;
i = 1;
while (i < vec_len (rv))
{
if (rv[i] == '.')
{
rv[last_label_index] = (i - last_label_index) - 1;
if ((i - last_label_index) > 63)
clib_warning ("stupid name, label length %d",
i - last_label_index);
last_label_index = i;
rv[i] = 0;
}
i++;
}
/* Set the last real label length */
rv[last_label_index] = (i - last_label_index) - 1;
/*
* Add a [sic] NULL root label. Otherwise, the name parser can't figure out
* where to stop.
*/
vec_add1 (rv, 0);
return rv;
}
/**
* arc-function for the above.
* Translate "0x3 f o o 0x3 c o m 0x0" into "foo.com"
* Produces a non-NULL-terminated u8 *vector. %v format is your friend.
*/
u8 *
labels_to_name (u8 * label, u8 * full_text, u8 ** parse_from_here)
{
u8 *reply = 0;
u16 offset;
u8 len;
int i;
*parse_from_here = 0;
/* chase initial pointer? */
if ((label[0] & 0xC0) == 0xC0)
{
*parse_from_here = label + 2;
offset = ((label[0] & 0x3f) << 8) + label[1];
label = full_text + offset;
}
len = *label++;
while (len)
{
for (i = 0; i < len; i++)
vec_add1 (reply, *label++);
/* chase pointer? */
if ((label[0] & 0xC0) == 0xC0)
{
*parse_from_here = label + 2;
offset = ((label[0] & 0x3f) << 8) + label[1];
label = full_text + offset;
}
len = *label++;
if (len)
vec_add1 (reply, '.');
}
if (*parse_from_here == 0)
*parse_from_here = label;
return reply;
}
void
vnet_send_dns_request (dns_main_t * dm, dns_cache_entry_t * ep)
{
dns_header_t *h;
dns_query_t *qp;
u16 tmp;
u8 *request;
u32 qp_offset;
/* This can easily happen if sitting in GDB, etc. */
if (ep->flags & DNS_CACHE_ENTRY_FLAG_VALID)
return;
/* Construct the dns request, if we haven't been here already */
if (vec_len (ep->dns_request) == 0)
{
/*
* Start with the variadic portion of the exercise.
* Turn the name into a set of DNS "labels". Max length
* per label is 63, enforce that.
*/
request = name_to_labels (ep->name);
qp_offset = vec_len (request);
/* Add space for the query header */
vec_validate (request, qp_offset + sizeof (dns_query_t) - 1);
qp = (dns_query_t *) (request + qp_offset);
qp->type = clib_host_to_net_u16 (DNS_TYPE_ALL);
qp->class = clib_host_to_net_u16 (DNS_CLASS_IN);
/* Punch in space for the dns_header_t */
vec_insert (request, sizeof (dns_header_t), 0);
h = (dns_header_t *) request;
/* Transaction ID = pool index */
h->id = clib_host_to_net_u16 (ep - dm->entries);
/* Ask for a recursive lookup */
tmp = DNS_RD | DNS_OPCODE_QUERY;
h->flags = clib_host_to_net_u16 (tmp);
h->qdcount = clib_host_to_net_u16 (1);
h->nscount = 0;
h->arcount = 0;
ep->dns_request = request;
}
/* Work out which server / address family we're going to use */
/* Retry using current server */
if (ep->retry_count++ < DNS_RETRIES_PER_SERVER)
{
if (ep->server_af == 1 /* ip6 */ )
{
if (vec_len (dm->ip6_name_servers))
{
send_dns6_request (dm, ep,
dm->ip6_name_servers + ep->server_rotor);
goto out;
}
else
ep->server_af = 0;
}
if (vec_len (dm->ip4_name_servers))
{
send_dns4_request (dm, ep, dm->ip4_name_servers + ep->server_rotor);
goto out;
}
}
else /* switch to a new server */
{
ep->retry_count = 1;
ep->server_rotor++;
if (ep->server_af == 1 /* ip6 */ )
{
if (ep->server_rotor >= vec_len (dm->ip6_name_servers))
{
ep->server_rotor = 0;
ep->server_af = vec_len (dm->ip4_name_servers) > 0 ? 0 : 1;
}
}
else
{
if (ep->server_rotor >= vec_len (dm->ip4_name_servers))
{
ep->server_rotor = 0;
ep->server_af = vec_len (dm->ip6_name_servers) > 0 ? 1 : 0;
}
}
}
if (ep->server_af == 1 /* ip6 */ )
send_dns6_request (dm, ep, dm->ip6_name_servers + ep->server_rotor);
else
send_dns4_request (dm, ep, dm->ip4_name_servers + ep->server_rotor);
out:
vlib_process_signal_event_mt (dm->vlib_main, dns_resolver_node.index,
DNS_RESOLVER_EVENT_PENDING, 0);
}
int
vnet_dns_delete_entry_by_index_nolock (dns_main_t * dm, u32 index)
{
dns_cache_entry_t *ep;
int i;
if (dm->is_enabled == 0)
return VNET_API_ERROR_NAME_RESOLUTION_NOT_ENABLED;
if (pool_is_free_index (dm->entries, index))
return VNET_API_ERROR_NO_SUCH_ENTRY;
ep = pool_elt_at_index (dm->entries, index);
if (!(ep->flags & DNS_CACHE_ENTRY_FLAG_VALID))
{
for (i = 0; i < vec_len (dm->unresolved_entries); i++)
if (index == dm->unresolved_entries[i])
{
vec_delete (dm->unresolved_entries, 1, i);
goto found;
}
clib_warning ("pool elt %d supposedly pending, but not found...",
index);
}
found:
hash_unset_mem (dm->cache_entry_by_name, ep->name);
vec_free (ep->name);
vec_free (ep->api_clients_to_notify);
vec_free (ep->api_client_contexts);
vec_free (ep->ip4_peers_to_notify);
vec_free (ep->ip6_peers_to_notify);
pool_put (dm->entries, ep);
return 0;
}
static int
dns_delete_by_name (dns_main_t * dm, u8 * name)
{
int rv;
uword *p;
if (dm->is_enabled == 0)
return VNET_API_ERROR_NAME_RESOLUTION_NOT_ENABLED;
dns_cache_lock (dm);
p = hash_get_mem (dm->cache_entry_by_name, name);
if (!p)
{
dns_cache_unlock (dm);
return VNET_API_ERROR_NO_SUCH_ENTRY;
}
rv = vnet_dns_delete_entry_by_index_nolock (dm, p[0]);
dns_cache_unlock (dm);
return rv;
}
static int
delete_random_entry (dns_main_t * dm)
{
int rv;
u32 victim_index, start_index, i;
u32 limit;
dns_cache_entry_t *ep;
if (dm->is_enabled == 0)
return VNET_API_ERROR_NAME_RESOLUTION_NOT_ENABLED;
/*
* Silence spurious coverity warning. We know pool_elts >> 0, or
* we wouldn't be here...
*/
#ifdef __COVERITY__
if (pool_elts (dm->entries) == 0)
return VNET_API_ERROR_UNSPECIFIED;
#endif
dns_cache_lock (dm);
limit = pool_elts (dm->entries);
start_index = random_u32 (&dm->random_seed) % limit;
for (i = 0; i < limit; i++)
{
victim_index = (start_index + i) % limit;
if (!pool_is_free_index (dm->entries, victim_index))
{
ep = pool_elt_at_index (dm->entries, victim_index);
/* Delete only valid, non-static entries */
if ((ep->flags & DNS_CACHE_ENTRY_FLAG_VALID)
&& ((ep->flags & DNS_CACHE_ENTRY_FLAG_STATIC) == 0))
{
rv = vnet_dns_delete_entry_by_index_nolock (dm, victim_index);
dns_cache_unlock (dm);
return rv;
}
}
}
dns_cache_unlock (dm);
clib_warning ("Couldn't find an entry to delete?");
return VNET_API_ERROR_UNSPECIFIED;
}
static int
dns_add_static_entry (dns_main_t * dm, u8 * name, u8 * dns_reply_data)
{
dns_cache_entry_t *ep;
uword *p;
int rv;
if (dm->is_enabled == 0)
return VNET_API_ERROR_NAME_RESOLUTION_NOT_ENABLED;
dns_cache_lock (dm);
p = hash_get_mem (dm->cache_entry_by_name, name);
if (p)
{
dns_cache_unlock (dm);
return VNET_API_ERROR_ENTRY_ALREADY_EXISTS;
}
if (pool_elts (dm->entries) == dm->name_cache_size)
{
/* Will only fail if the cache is totally filled w/ static entries... */
rv = delete_random_entry (dm);
if (rv)
{
dns_cache_unlock (dm);
return rv;
}
}
pool_get (dm->entries, ep);
memset (ep, 0, sizeof (*ep));
/* Note: consumes the name vector */
ep->name = name;
hash_set_mem (dm->cache_entry_by_name, ep->name, ep - dm->entries);
ep->flags = DNS_CACHE_ENTRY_FLAG_VALID | DNS_CACHE_ENTRY_FLAG_STATIC;
ep->dns_response = dns_reply_data;
dns_cache_unlock (dm);
return 0;
}
static int
dns_resolve_name (dns_main_t * dm,
u8 * name, u32 client_index, u32 client_context,
dns_cache_entry_t ** retp)
{
dns_cache_entry_t *ep;
int rv;
f64 now;
uword *p;
now = vlib_time_now (dm->vlib_main);
/* In case we can't actually answer the question right now... */
*retp = 0;
dns_cache_lock (dm);
search_again:
p = hash_get_mem (dm->cache_entry_by_name, name);
if (p)
{
ep = pool_elt_at_index (dm->entries, p[0]);
if (ep->flags & DNS_CACHE_ENTRY_FLAG_VALID)
{
/* Has the entry expired? */
if (((ep->flags & DNS_CACHE_ENTRY_FLAG_STATIC) == 0)
&& (now > ep->expiration_time))
{
int i;
u32 *indices_to_delete = 0;
/*
* Take out the rest of the resolution chain
* This isn't optimal, but it won't happen very often.
*/
while (ep)
{
if ((ep->flags & DNS_CACHE_ENTRY_FLAG_CNAME))
{
vec_add1 (indices_to_delete, ep - dm->entries);
p = hash_get_mem (dm->cache_entry_by_name, ep->cname);
if (!p)
break;
ep = pool_elt_at_index (dm->entries, p[0]);
}
else
{
vec_add1 (indices_to_delete, ep - dm->entries);
break;
}
}
for (i = 0; i < vec_len (indices_to_delete); i++)
{
/* Reenable to watch re-resolutions */
if (0)
{
ep = pool_elt_at_index (dm->entries,
indices_to_delete[i]);
clib_warning ("Re-resolve %s", ep->name);
}
vnet_dns_delete_entry_by_index_nolock
(dm, indices_to_delete[i]);
}
vec_free (indices_to_delete);
/* Yes, kill it... */
goto re_resolve;
}
if (ep->flags & DNS_CACHE_ENTRY_FLAG_CNAME)
{
name = ep->cname;
goto search_again;
}
/* Note: caller must drop the lock! */
*retp = ep;
return (0);
}
else
{
/*
* Resolution pending. Add request to the pending vector(s) */
vec_add1 (ep->api_clients_to_notify, client_index);
vec_add1 (ep->api_client_contexts, client_context);
dns_cache_unlock (dm);
return (0);
}
}
re_resolve:
if (pool_elts (dm->entries) == dm->name_cache_size)
{
/* Will only fail if the cache is totally filled w/ static entries... */
rv = delete_random_entry (dm);
if (rv)
{
dns_cache_unlock (dm);
return rv;
}
}
/* add new hash table entry */
pool_get (dm->entries, ep);
memset (ep, 0, sizeof (*ep));
ep->name = format (0, "%s%c", name, 0);
_vec_len (ep->name) = vec_len (ep->name) - 1;
hash_set_mem (dm->cache_entry_by_name, ep->name, ep - dm->entries);
vec_add1 (dm->unresolved_entries, ep - dm->entries);
vec_add1 (ep->api_clients_to_notify, client_index);
vec_add1 (ep->api_client_contexts, client_context);
vnet_send_dns_request (dm, ep);
dns_cache_unlock (dm);
return 0;
}
#define foreach_notification_to_move \
_(api_clients_to_notify) \
_(api_client_contexts) \
_(ip4_peers_to_notify) \
_(ip6_peers_to_notify)
/**
* Handle cname indirection. JFC. Called with the cache locked.
* returns 0 if the reply is not a CNAME.
*/
int
vnet_dns_cname_indirection_nolock (dns_main_t * dm, u32 ep_index, u8 * reply)
{
dns_header_t *h;
dns_query_t *qp;
dns_rr_t *rr;
u8 *curpos;
u8 *pos, *pos2;
int len, i;
u8 *cname = 0;
u8 *request = 0;
u32 qp_offset;
u16 flags;
u16 rcode;
dns_cache_entry_t *ep, *next_ep;
f64 now;
h = (dns_header_t *) reply;
flags = clib_net_to_host_u16 (h->flags);
rcode = flags & DNS_RCODE_MASK;
/* See if the response is OK */
switch (rcode)
{
case DNS_RCODE_NO_ERROR:
break;
case DNS_RCODE_NAME_ERROR:
case DNS_RCODE_FORMAT_ERROR:
case DNS_RCODE_SERVER_FAILURE:
case DNS_RCODE_NOT_IMPLEMENTED:
case DNS_RCODE_REFUSED:
return 0;
}
curpos = (u8 *) (h + 1);
pos = curpos;
len = *pos++;
/* Skip the questions */
for (i = 0; i < clib_net_to_host_u16 (h->qdcount); i++)
{
while (len)
{
pos += len;
len = *pos++;
}
pos += sizeof (dns_query_t);
}
pos2 = pos;
/* expect a pointer chase here for a CNAME record */
if ((pos2[0] & 0xC0) == 0xC0)
pos += 2;
else
return 0;
rr = (dns_rr_t *) pos;
/* This is a real record, not a CNAME record */
if (clib_net_to_host_u16 (rr->type) != DNS_TYPE_CNAME)
return 0;
/* This is a CNAME record, chase the name chain. */
/* The last request is no longer pending.. */
for (i = 0; i < vec_len (dm->unresolved_entries); i++)
if (ep_index == dm->unresolved_entries[i])
{
vec_delete (dm->unresolved_entries, 1, i);
goto found_last_request;
}
clib_warning ("pool elt %d supposedly pending, but not found...", ep_index);
found_last_request:
now = vlib_time_now (dm->vlib_main);
cname = labels_to_name (rr->rdata, reply, &pos2);
/* Save the cname */
vec_add1 (cname, 0);
_vec_len (cname) -= 1;
ep = pool_elt_at_index (dm->entries, ep_index);
ep->cname = cname;
ep->flags |= (DNS_CACHE_ENTRY_FLAG_CNAME | DNS_CACHE_ENTRY_FLAG_VALID);
/* Save the response */
ep->dns_response = reply;
/* Set up expiration time */
ep->expiration_time = now + clib_net_to_host_u32 (rr->ttl);
pool_get (dm->entries, next_ep);
/* Need to recompute ep post pool-get */
ep = pool_elt_at_index (dm->entries, ep_index);
memset (next_ep, 0, sizeof (*next_ep));
next_ep->name = vec_dup (cname);
vec_add1 (next_ep->name, 0);
_vec_len (next_ep->name) -= 1;
hash_set_mem (dm->cache_entry_by_name, next_ep->name,
next_ep - dm->entries);
/* Use the same server */
next_ep->server_rotor = ep->server_rotor;
next_ep->server_af = ep->server_af;
/* Move notification data to the next name in the chain */
#define _(a) next_ep->a = ep->a; ep->a = 0;
foreach_notification_to_move;
#undef _
request = name_to_labels (cname);
qp_offset = vec_len (request);
/* Add space for the query header */
vec_validate (request, qp_offset + sizeof (dns_query_t) - 1);
qp = (dns_query_t *) (request + qp_offset);
qp->type = clib_host_to_net_u16 (DNS_TYPE_ALL);
qp->class = clib_host_to_net_u16 (DNS_CLASS_IN);
/* Punch in space for the dns_header_t */
vec_insert (request, sizeof (dns_header_t), 0);
h = (dns_header_t *) request;
/* Transaction ID = pool index */
h->id = clib_host_to_net_u16 (next_ep - dm->entries);
/* Ask for a recursive lookup */
h->flags = clib_host_to_net_u16 (DNS_RD | DNS_OPCODE_QUERY);
h->qdcount = clib_host_to_net_u16 (1);
h->nscount = 0;
h->arcount = 0;
next_ep->dns_request = request;
next_ep->retry_timer = now + 2.0;
next_ep->retry_count = 0;
/*
* Enable this to watch recursive resolution happen...
* fformat (stdout, "%U", format_dns_reply, request, 2);
*/
vec_add1 (dm->unresolved_entries, next_ep - dm->entries);
vnet_send_dns_request (dm, next_ep);
return (1);
}
int
vnet_dns_response_to_reply (u8 * response,
vl_api_dns_resolve_name_reply_t * rmp,
u32 * min_ttlp)
{
dns_header_t *h;
dns_query_t *qp;
dns_rr_t *rr;
int i, limit;
u8 len;
u8 *curpos, *pos;
u16 flags;
u16 rcode;
u32 ttl;
h = (dns_header_t *) response;
flags = clib_net_to_host_u16 (h->flags);
rcode = flags & DNS_RCODE_MASK;
/* See if the response is OK, etc. */
switch (rcode)
{
default:
case DNS_RCODE_NO_ERROR:
break;
case DNS_RCODE_NAME_ERROR:
case DNS_RCODE_FORMAT_ERROR:
return VNET_API_ERROR_NAME_SERVER_NO_SUCH_NAME;
case DNS_RCODE_SERVER_FAILURE:
case DNS_RCODE_NOT_IMPLEMENTED:
case DNS_RCODE_REFUSED:
return VNET_API_ERROR_NAME_SERVER_NEXT_SERVER;
}
/* No answers? Loser... */
if (clib_net_to_host_u16 (h->anscount) < 1)
return VNET_API_ERROR_NAME_SERVER_NO_ADDRESSES;
curpos = (u8 *) (h + 1);
/* Skip the name we asked about */
pos = curpos;
len = *pos++;
/* Should never happen, but stil... */
if ((len & 0xC0) == 0xC0)
curpos += 2;
else
{
/* skip the name / label-set */
while (len)
{
pos += len;
len = *pos++;
}
curpos = pos;
}
/* Skip queries */
limit = clib_net_to_host_u16 (h->qdcount);
qp = (dns_query_t *) curpos;
qp += limit;
curpos = (u8 *) qp;
/* Parse answers */
limit = clib_net_to_host_u16 (h->anscount);
for (i = 0; i < limit; i++)
{
pos = curpos;
/* Expect pointer chases in the answer section... */
if ((pos[0] & 0xC0) == 0xC0)
curpos += 2;
else
{
len = *pos++;
while (len)
{
if ((pos[0] & 0xC0) == 0xC0)
{
curpos = pos + 2;
goto curpos_set;
}
pos += len;
len = *pos++;
}
curpos = pos;
}
curpos_set:
rr = (dns_rr_t *) curpos;
switch (clib_net_to_host_u16 (rr->type))
{
case DNS_TYPE_A:
/* Collect an ip4 address. Do not pass go. Do not collect $200 */
memcpy (rmp->ip4_address, rr->rdata, sizeof (ip4_address_t));
rmp->ip4_set = 1;
ttl = clib_net_to_host_u32 (rr->ttl);
if (min_ttlp && *min_ttlp > ttl)
*min_ttlp = ttl;
break;
case DNS_TYPE_AAAA:
/* Collect an ip6 address. Do not pass go. Do not collect $200 */
memcpy (rmp->ip6_address, rr->rdata, sizeof (ip6_address_t));
ttl = clib_net_to_host_u32 (rr->ttl);
if (min_ttlp && *min_ttlp > ttl)
*min_ttlp = ttl;
rmp->ip6_set = 1;
break;
default:
break;
}
/* Might as well stop ASAP */
if (rmp->ip4_set && rmp->ip6_set)
break;
curpos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
}
if ((rmp->ip4_set + rmp->ip6_set) == 0)
return VNET_API_ERROR_NAME_SERVER_NO_ADDRESSES;
return 0;
}
static void
vl_api_dns_resolve_name_t_handler (vl_api_dns_resolve_name_t * mp)
{
dns_main_t *dm = &dns_main;
vl_api_dns_resolve_name_reply_t *rmp;
dns_cache_entry_t *ep;
int rv;
/* Sanitize the name slightly */
mp->name[ARRAY_LEN (mp->name) - 1] = 0;
rv = dns_resolve_name (dm, mp->name, mp->client_index, mp->context, &ep);
/* Error, e.g. not enabled? Tell the user */
if (rv < 0)
{
REPLY_MACRO (VL_API_DNS_RESOLVE_NAME_REPLY);
return;
}
/* Resolution pending? Don't reply... */
if (ep == 0)
return;
/* *INDENT-OFF* */
REPLY_MACRO2(VL_API_DNS_RESOLVE_NAME_REPLY,
({
rv = vnet_dns_response_to_reply (ep->dns_response, rmp, 0 /* ttl-ptr */);
rmp->retval = clib_host_to_net_u32 (rv);
}));
/* *INDENT-ON* */
/*
* dns_resolve_name leaves the cache locked when it returns
* a cached result, so unlock it here.
*/
dns_cache_unlock (dm);
}
#define vl_msg_name_crc_list
#include <vpp/api/vpe_all_api_h.h>
#undef vl_msg_name_crc_list
static void
setup_message_id_table (api_main_t * am)
{
#define _(id,n,crc) vl_msg_api_add_msg_name_crc (am, #n "_" #crc, id);
foreach_vl_msg_name_crc_dns;
#undef _
}
#define foreach_dns_api_msg \
_(DNS_ENABLE_DISABLE, dns_enable_disable) \
_(DNS_NAME_SERVER_ADD_DEL, dns_name_server_add_del) \
_(DNS_RESOLVE_NAME, dns_resolve_name)
static clib_error_t *
dns_api_hookup (vlib_main_t * vm)
{
#define _(N,n) \
vl_msg_api_set_handlers(VL_API_##N, #n, \
vl_api_##n##_t_handler, \
vl_noop_handler, \
vl_api_##n##_t_endian, \
vl_api_##n##_t_print, \
sizeof(vl_api_##n##_t), 1);
foreach_dns_api_msg;
#undef _
setup_message_id_table (&api_main);
return 0;
}
VLIB_API_INIT_FUNCTION (dns_api_hookup);
static clib_error_t *
dns_config_fn (vlib_main_t * vm, unformat_input_t * input)
{
dns_main_t *dm = &dns_main;
while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
{
if (unformat (input, "max-cache-size %u", &dm->name_cache_size))
;
else if (unformat (input, "max-ttl %u", &dm->max_ttl_in_seconds))
;
else
return clib_error_return (0, "unknown input `%U'",
format_unformat_error, input);
}
return 0;
}
VLIB_CONFIG_FUNCTION (dns_config_fn, "dns");
static clib_error_t *
dns_init (vlib_main_t * vm)
{
dns_main_t *dm = &dns_main;
dm->vlib_main = vm;
dm->vnet_main = vnet_get_main ();
dm->name_cache_size = 65535;
dm->max_ttl_in_seconds = 86400;
dm->random_seed = 0xDEADDABE;
udp_register_dst_port (vm, UDP_DST_PORT_dns_reply, dns46_reply_node.index,
1 /* is_ip4 */ );
udp_register_dst_port (vm, UDP_DST_PORT_dns_reply6, dns46_reply_node.index,
0 /* is_ip4 */ );
#if 0
udp_register_dst_port (vm, UDP_DST_PORT_dns, dns4_request_node.index,
1 /* is_ip4 */ );
udp_register_dst_port (vm, UDP_DST_PORT_dns6, dns6_request_node.index,
0 /* is_ip4 */ );
#endif
return 0;
}
VLIB_INIT_FUNCTION (dns_init);
uword
unformat_dns_reply (unformat_input_t * input, va_list * args)
{
u8 **result = va_arg (*args, u8 **);
u8 **namep = va_arg (*args, u8 **);
ip4_address_t a4;
ip6_address_t a6;
int a4_set = 0;
int a6_set = 0;
u8 *name;
int name_set = 0;
u8 *ce;
u32 qp_offset;
dns_header_t *h;
dns_query_t *qp;
dns_rr_t *rr;
u8 *rru8;
if (unformat (input, "%v", &name))
name_set = 1;
if (unformat (input, "%U", unformat_ip4_address, &a4))
{
a4_set = 1;
if (unformat (input, "%U", unformat_ip6_address, &a6))
a6_set = 1;
}
if (unformat (input, "%U", unformat_ip6_address, &a6))
{
a6_set = 1;
if (unformat (input, "%U", unformat_ip4_address, &a6))
a4_set = 1;
}
/* Must have a name */
if (!name_set)
return 0;
/* Must have at least one address */
if (!(a4_set + a6_set))
return 0;
/* Build a fake DNS cache entry string, one hemorrhoid at a time */
ce = name_to_labels (name);
qp_offset = vec_len (ce);
/* Add space for the query header */
vec_validate (ce, qp_offset + sizeof (dns_query_t) - 1);
qp = (dns_query_t *) (ce + qp_offset);
qp->type = clib_host_to_net_u16 (DNS_TYPE_ALL);
qp->class = clib_host_to_net_u16 (DNS_CLASS_IN);
/* Punch in space for the dns_header_t */
vec_insert (ce, sizeof (dns_header_t), 0);
h = (dns_header_t *) ce;
/* Fake Transaction ID */
h->id = 0xFFFF;
h->flags = clib_host_to_net_u16 (DNS_RD | DNS_RA);
h->qdcount = clib_host_to_net_u16 (1);
h->anscount = clib_host_to_net_u16 (a4_set + a6_set);
h->nscount = 0;
h->arcount = 0;
/* Now append one or two A/AAAA RR's... */
if (a4_set)
{
/* Pointer to the name (DGMS) */
vec_add1 (ce, 0xC0);
vec_add1 (ce, 0x0C);
vec_add2 (ce, rru8, sizeof (*rr) + 4);
rr = (void *) rru8;
rr->type = clib_host_to_net_u16 (DNS_TYPE_A);
rr->class = clib_host_to_net_u16 (DNS_CLASS_IN);
rr->ttl = clib_host_to_net_u32 (86400);
rr->rdlength = clib_host_to_net_u16 (4);
memcpy (rr->rdata, &a4, sizeof (a4));
}
if (a6_set)
{
/* Pointer to the name (DGMS) */
vec_add1 (ce, 0xC0);
vec_add1 (ce, 0x0C);
vec_add2 (ce, rru8, sizeof (*rr) + 16);
rr = (void *) rru8;
rr->type = clib_host_to_net_u16 (DNS_TYPE_AAAA);
rr->class = clib_host_to_net_u16 (DNS_CLASS_IN);
rr->ttl = clib_host_to_net_u32 (86400);
rr->rdlength = clib_host_to_net_u16 (16);
memcpy (rr->rdata, &a6, sizeof (a6));
}
*result = ce;
if (namep)
*namep = name;
else
vec_free (name);
return 1;
}
u8 *
format_dns_query (u8 * s, va_list * args)
{
u8 **curpos = va_arg (*args, u8 **);
int verbose = va_arg (*args, int);
u8 *pos;
dns_query_t *qp;
int len, i;
if (verbose > 1)
s = format (s, " Name: ");
/* Unwind execrated counted-label sheit */
pos = *curpos;
len = *pos++;
while (len)
{
for (i = 0; i < len; i++)
vec_add1 (s, *pos++);
len = *pos++;
if (len)
vec_add1 (s, '.');
else
{
vec_add1 (s, ':');
vec_add1 (s, ' ');
}
}
qp = (dns_query_t *) pos;
if (verbose > 1)
{
switch (clib_net_to_host_u16 (qp->type))
{
case DNS_TYPE_A:
s = format (s, "type A\n");
break;
case DNS_TYPE_AAAA:
s = format (s, "type AAAA\n");
break;
case DNS_TYPE_ALL:
s = format (s, "type ALL\n");
break;
default:
s = format (s, "type %d\n", clib_net_to_host_u16 (qp->type));
break;
}
}
pos += sizeof (*qp);
*curpos = pos;
return s;
}
/**
* format dns reply data
* verbose > 1, dump everything
* verbose == 1, dump all A and AAAA records
* verbose == 0, dump one A record, and one AAAA record
*/
u8 *
format_dns_reply_data (u8 * s, va_list * args)
{
u8 *reply = va_arg (*args, u8 *);
u8 **curpos = va_arg (*args, u8 **);
int verbose = va_arg (*args, int);
int *print_ip4 = va_arg (*args, int *);
int *print_ip6 = va_arg (*args, int *);
int len;
u8 *pos, *pos2;
dns_rr_t *rr;
int i;
int initial_pointer_chase = 0;
u16 *tp;
pos = pos2 = *curpos;
if (verbose > 1)
s = format (s, " ");
/* chase pointer? almost always yes here... */
if (pos2[0] == 0xc0)
{
pos2 = reply + pos2[1];
pos += 2;
initial_pointer_chase = 1;
}
len = *pos2++;
while (len)
{
for (i = 0; i < len; i++)
{
if (verbose > 1)
vec_add1 (s, *pos2);
pos2++;
}
len = *pos2++;
if (len)
{
if (verbose > 1)
vec_add1 (s, '.');
}
else
{
if (verbose > 1)
vec_add1 (s, ' ');
}
}
if (initial_pointer_chase == 0)
pos = pos2;
rr = (dns_rr_t *) pos;
switch (clib_net_to_host_u16 (rr->type))
{
case DNS_TYPE_A:
if (verbose > 1)
{
s = format (s, "A: ttl %d %U\n", clib_net_to_host_u32 (rr->ttl),
format_ip4_address, rr->rdata);
}
else
{
if (*print_ip4)
s = format (s, "%U [%u] ", format_ip4_address, rr->rdata,
clib_net_to_host_u32 (rr->ttl));
if (verbose == 0)
*print_ip4 = 0;
}
pos += sizeof (*rr) + 4;
break;
case DNS_TYPE_AAAA:
if (verbose > 1)
{
s = format (s, "AAAA: ttl %d %U\n", clib_net_to_host_u32 (rr->ttl),
format_ip6_address, rr->rdata);
}
else
{
if (*print_ip6)
s = format (s, "%U [%u] ", format_ip6_address, rr->rdata,
clib_net_to_host_u32 (rr->ttl));
if (verbose == 0)
*print_ip6 = 0;
}
pos += sizeof (*rr) + 16;
break;
case DNS_TYPE_TEXT:
if (verbose > 1)
{
s = format (s, "TEXT: ");
for (i = 0; i < clib_net_to_host_u16 (rr->rdlength); i++)
vec_add1 (s, rr->rdata[i]);
vec_add1 (s, '\n');
}
pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
break;
case DNS_TYPE_HINFO:
{
/* Two counted strings. DGMS */
u8 *len;
u8 *curpos;
int i;
if (verbose > 1)
{
s = format (s, "HINFO: ");
len = rr->rdata;
curpos = len + 1;
for (i = 0; i < *len; i++)
vec_add1 (s, *curpos++);
vec_add1 (s, ' ');
len = curpos++;
for (i = 0; i < *len; i++)
vec_add1 (s, *curpos++);
vec_add1 (s, '\n');
}
}
pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
break;
case DNS_TYPE_NAMESERVER:
if (verbose > 1)
{
s = format (s, "Nameserver: ");
pos2 = rr->rdata;
/* chase pointer? */
if (pos2[0] == 0xc0)
pos2 = reply + pos2[1];
len = *pos2++;
while (len)
{
for (i = 0; i < len; i++)
vec_add1 (s, *pos2++);
/* chase pointer, typically to offset 12... */
if (pos2[0] == 0xC0)
pos2 = reply + pos2[1];
len = *pos2++;
if (len)
vec_add1 (s, '.');
else
vec_add1 (s, '\n');
}
}
pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
break;
case DNS_TYPE_MAIL_EXCHANGE:
if (verbose > 1)
{
tp = (u16 *) rr->rdata;
s = format (s, "Mail Exchange: Preference %d ", (u32)
clib_net_to_host_u16 (*tp));
pos2 = rr->rdata + 2;
/* chase pointer? */
if (pos2[0] == 0xc0)
pos2 = reply + pos2[1];
len = *pos2++;
while (len)
{
for (i = 0; i < len; i++)
vec_add1 (s, *pos2++);
/* chase pointer */
if (pos2[0] == 0xC0)
pos2 = reply + pos2[1];
len = *pos2++;
if (len)
vec_add1 (s, '.');
else
vec_add1 (s, '\n');
}
}
pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
break;
case DNS_TYPE_CNAME:
if (verbose > 1)
{
tp = (u16 *) rr->rdata;
s = format (s, "CNAME: ");
pos2 = rr->rdata;
/* chase pointer? */
if (pos2[0] == 0xc0)
pos2 = reply + pos2[1];
len = *pos2++;
while (len)
{
for (i = 0; i < len; i++)
vec_add1 (s, *pos2++);
/* chase pointer */
if (pos2[0] == 0xC0)
pos2 = reply + pos2[1];
len = *pos2++;
if (len)
vec_add1 (s, '.');
else
vec_add1 (s, '\n');
}
}
pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
break;
default:
if (verbose > 1)
s = format (s, "type %d: len %d\n",
(int) clib_net_to_host_u16 (rr->type),
sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength));
pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
break;
}
*curpos = pos;
return s;
}
u8 *
format_dns_reply (u8 * s, va_list * args)
{
u8 *reply_as_u8 = va_arg (*args, u8 *);
int verbose = va_arg (*args, int);
dns_header_t *h;
u16 id, flags;
u8 *curpos;
int i;
int print_ip4 = 1;
int print_ip6 = 1;
h = (dns_header_t *) reply_as_u8;
id = clib_net_to_host_u16 (h->id);
flags = clib_net_to_host_u16 (h->flags);
if (verbose > 1)
{
s = format (s, "DNS %s: id %d\n", (flags & DNS_QR) ? "reply" : "query",
id);
s = format (s, " %s %s %s %s\n",
(flags & DNS_RA) ? "recur" : "no-recur",
(flags & DNS_RD) ? "recur-des" : "no-recur-des",
(flags & DNS_TC) ? "trunc" : "no-trunc",
(flags & DNS_AA) ? "auth" : "non-auth");
s = format (s, " %d queries, %d answers, %d name-servers,"
" %d add'l recs\n",
clib_net_to_host_u16 (h->qdcount),
clib_net_to_host_u16 (h->anscount),
clib_net_to_host_u16 (h->nscount),
clib_net_to_host_u16 (h->arcount));
}
curpos = (u8 *) (h + 1);
if (h->qdcount)
{
if (verbose > 1)
s = format (s, " Queries:\n");
for (i = 0; i < clib_net_to_host_u16 (h->qdcount); i++)
{
/* The query is variable-length, so curpos is a value-result parm */
s = format (s, "%U", format_dns_query, &curpos, verbose);
}
}
if (h->anscount)
{
if (verbose > 1)
s = format (s, " Replies:\n");
for (i = 0; i < clib_net_to_host_u16 (h->anscount); i++)
{
/* curpos is a value-result parm */
s = format (s, "%U", format_dns_reply_data, reply_as_u8, &curpos,
verbose, &print_ip4, &print_ip6);
}
}
return s;
}
u8 *
format_dns_cache (u8 * s, va_list * args)
{
dns_main_t *dm = va_arg (*args, dns_main_t *);
f64 now = va_arg (*args, f64);
int verbose = va_arg (*args, int);
u8 *name = va_arg (*args, u8 *);
dns_cache_entry_t *ep;
char *ss;
uword *p;
if (dm->is_enabled == 0)
{
s = format (s, "The DNS cache is disabled...");
return s;
}
if (pool_elts (dm->entries) == 0)
{
s = format (s, "The DNS cache is empty...");
return s;
}
dns_cache_lock (dm);
if (name)
{
p = hash_get_mem (dm->cache_entry_by_name, name);
if (!p)
{
s = format (s, "%s is not in the cache...", name);
dns_cache_unlock (dm);
return (s);
}
ep = pool_elt_at_index (dm->entries, p[0]);
/* Magic to spit out a C-initializer to research hemorrhoids... */
if (verbose == 3)
{
int i, j;
s = format (s, "static u8 dns_reply_data_initializer[] =\n");
s = format (s, "{\n");
j = 0;
for (i = 0; i < vec_len (ep->dns_response); i++)
{
if (j++ == 8)
{
j = 0;
vec_add1 (s, '\n');
}
s = format (s, "0x%02x, ", ep->dns_response[i]);
}
s = format (s, "};\n");
}
else
{
if (ep->flags & DNS_CACHE_ENTRY_FLAG_VALID)
{
ASSERT (ep->dns_response);
if (ep->flags & DNS_CACHE_ENTRY_FLAG_STATIC)
ss = "[S] ";
else
ss = " ";
if (verbose < 2 && ep->flags & DNS_CACHE_ENTRY_FLAG_CNAME)
s = format (s, "%s%s -> %s", ss, ep->name, ep->cname);
else
s = format (s, "%s%s -> %U", ss, ep->name,
format_dns_reply, ep->dns_response, verbose);
if (!(ep->flags & DNS_CACHE_ENTRY_FLAG_STATIC))
{
f64 time_left = ep->expiration_time - now;
if (time_left > 0.0)
s = format (s, " TTL left %.1f", time_left);
else
s = format (s, " EXPIRED");
}
}
else
{
ASSERT (ep->dns_request);
s = format (s, "[P] %U", format_dns_reply, ep->dns_request,
verbose);
}
vec_add1 (s, '\n');
}
return s;
}
/* *INDENT-OFF* */
pool_foreach (ep, dm->entries,
({
if (ep->flags & DNS_CACHE_ENTRY_FLAG_VALID)
{
ASSERT (ep->dns_response);
if (ep->flags & DNS_CACHE_ENTRY_FLAG_STATIC)
ss = "[S] ";
else
ss = " ";
if (verbose < 2 && ep->flags & DNS_CACHE_ENTRY_FLAG_CNAME)
s = format (s, "%s%s -> %s", ss, ep->name, ep->cname);
else
s = format (s, "%s%s -> %U", ss, ep->name,
format_dns_reply,
ep->dns_response,
verbose);
if (!(ep->flags & DNS_CACHE_ENTRY_FLAG_STATIC))
{
f64 time_left = ep->expiration_time - now;
if (time_left > 0.0)
s = format (s, " TTL left %.1f", time_left);
else
s = format (s, " EXPIRED");
if (verbose > 2)
s = format (s, " %d client notifications pending\n",
vec_len(ep->api_clients_to_notify));
}
}
else
{
ASSERT (ep->dns_request);
s = format (s, "[P] %U", format_dns_reply, ep->dns_request,
verbose);
}
vec_add1 (s, '\n');
}));
/* *INDENT-ON* */
dns_cache_unlock (dm);
return s;
}
static clib_error_t *
show_dns_cache_command_fn (vlib_main_t * vm,
unformat_input_t * input, vlib_cli_command_t * cmd)
{
dns_main_t *dm = &dns_main;
int verbose = 0;
u8 *name = 0;
f64 now = vlib_time_now (vm);
while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
{
if (unformat (input, "verbose %d", &verbose))
;
else if (unformat (input, "verbose"))
verbose = 1;
else if (unformat (input, "name %s", &name))
;
else
return clib_error_return (0, "unknown input `%U'",
format_unformat_error, input);
}
vlib_cli_output (vm, "%U", format_dns_cache, dm, now, verbose, name);
return 0;
}
/* *INDENT-OFF* */
VLIB_CLI_COMMAND (show_dns_cache_command) =
{
.path = "show dns cache",
.short_help = "show dns cache [verbose [nn]]",
.function = show_dns_cache_command_fn,
};
/* *INDENT-ON* */
static clib_error_t *
dns_cache_add_del_command_fn (vlib_main_t * vm,
unformat_input_t * input,
vlib_cli_command_t * cmd)
{
dns_main_t *dm = &dns_main;
u8 *dns_reply_data;
u8 *name;
int is_add = -1;
int is_clear = -1;
int rv;
clib_error_t *error;
if (unformat (input, "add"))
is_add = 1;
if (unformat (input, "del"))
is_add = 0;
if (unformat (input, "clear"))
is_clear = 1;
if (is_add == -1 && is_clear == -1)
return clib_error_return (0, "add / del / clear required...");
if (is_clear == 1)
{
rv = dns_cache_clear (dm);
switch (rv)
{
case 0:
return 0;
case VNET_API_ERROR_NAME_RESOLUTION_NOT_ENABLED:
error = clib_error_return (0, "Name resolution not enabled");
return error;
}
}
/* Delete (by name)? */
if (is_add == 0)
{
if (unformat (input, "%v", &name))
{
rv = dns_delete_by_name (dm, name);
switch (rv)
{
case VNET_API_ERROR_NO_SUCH_ENTRY:
error = clib_error_return (0, "%v not in the cache...", name);
vec_free (name);
return error;
case VNET_API_ERROR_NAME_RESOLUTION_NOT_ENABLED:
error = clib_error_return (0, "Name resolution not enabled");
vec_free (name);
return error;
case 0:
vec_free (name);
return 0;
default:
error = clib_error_return (0, "dns_delete_by_name returned %d",
rv);
vec_free (name);
return error;
}
}
return clib_error_return (0, "unknown input `%U'",
format_unformat_error, input);
}
/* Note: dns_add_static_entry consumes the name vector if OK... */
if (unformat (input, "%U", unformat_dns_reply, &dns_reply_data, &name))
{
rv = dns_add_static_entry (dm, name, dns_reply_data);
switch (rv)
{
case VNET_API_ERROR_ENTRY_ALREADY_EXISTS:
vec_free (name);
vec_free (dns_reply_data);
return clib_error_return (0, "%v already in the cache...", name);
case 0:
return 0;
default:
return clib_error_return (0, "dns_add_static_entry returned %d",
rv);
}
}
return 0;
}
/* *INDENT-OFF* */
VLIB_CLI_COMMAND (dns_cache_add_del_command) =
{
.path = "dns cache",
.short_help = "dns cache [add|del|clear] <name> [ip4][ip6]",
.function = dns_cache_add_del_command_fn,
};
/* *INDENT-ON* */
#define DNS_FORMAT_TEST 1
#if DNS_FORMAT_TEST > 0
#if 0
/* yahoo.com */
static u8 dns_reply_data_initializer[] =
{ 0x0, 0x0, 0x81, 0x80, 0x0, 0x1, 0x0, 0x10, 0x0, 0x0, 0x0, 0x0, 0x5,
0x79, 0x61, 0x68, 0x6f, 0x6f, 0x3, 0x63, 0x6f, 0x6d,
0x0, /* null lbl */
0x0, 0xff, /* type ALL */
0x0, 0x1, /* class IN */
0xc0, 0xc, /* pointer to yahoo.com name */
0x0, 0x10, 0x0, 0x1, 0x0, 0x0, 0x6, 0x5c, 0x0, 0x24, 0x23,
0x76, 0x3d, 0x73, 0x70, 0x66, 0x31, 0x20, 0x72, 0x65, 0x64, 0x69, 0x72,
0x65, 0x63, 0x74, 0x3d, 0x5f, 0x73, 0x70, 0x66, 0x2e, 0x6d, 0x61, 0x69,
0x6c, 0x2e, 0x79, 0x61, 0x68, 0x6f, 0x6f, 0x2e, 0x63, 0x6f, 0x6d, 0xc0,
0xc, 0x0, 0x2, 0x0, 0x1, 0x0, 0x1, 0x50, 0xd4, 0x0, 0x6, 0x3, 0x6e, 0x73,
0x35, 0xc0, 0xc, 0xc0, 0xc, 0x0, 0x2, 0x0, 0x1, 0x0, 0x1, 0x50, 0xd4, 0x0,
0x6, 0x3, 0x6e, 0x73, 0x34, 0xc0, 0xc, 0xc0, 0xc, 0x0, 0x2, 0x0, 0x1, 0x0,
0x1, 0x50, 0xd4, 0x0, 0x6, 0x3, 0x6e, 0x73, 0x31, 0xc0, 0xc, 0xc0, 0xc,
0x0, 0x2, 0x0, 0x1, 0x0, 0x1, 0x50, 0xd4, 0x0, 0x6, 0x3, 0x6e, 0x73, 0x32,
0xc0, 0xc, 0xc0, 0xc, 0x0, 0x2, 0x0, 0x1, 0x0, 0x1, 0x50, 0xd4, 0x0, 0x6,
0x3, 0x6e, 0x73, 0x33, 0xc0, 0xc, 0xc0, 0xc, 0x0, 0xf, 0x0, 0x1, 0x0, 0x0,
0x6, 0x5c, 0x0, 0x19, 0x0, 0x1, 0x4, 0x6d, 0x74, 0x61, 0x36, 0x3, 0x61,
0x6d, 0x30, 0x8, 0x79, 0x61, 0x68, 0x6f, 0x6f, 0x64, 0x6e, 0x73, 0x3,
0x6e,
0x65, 0x74, 0x0, 0xc0, 0xc, 0x0, 0xf, 0x0, 0x1, 0x0, 0x0, 0x6, 0x5c, 0x0,
0x9, 0x0, 0x1, 0x4, 0x6d, 0x74, 0x61, 0x37, 0xc0, 0xb8, 0xc0, 0xc, 0x0,
0xf, 0x0, 0x1, 0x0, 0x0, 0x6, 0x5c, 0x0, 0x9, 0x0, 0x1, 0x4, 0x6d, 0x74,
0x61, 0x35, 0xc0, 0xb8, 0xc0, 0xc, 0x0, 0x1c, 0x0, 0x1, 0x0, 0x0, 0x6,
0x5c, 0x0, 0x10, 0x20, 0x1, 0x49, 0x98, 0x0, 0x44, 0x2, 0x4, 0x0, 0x0,
0x0,
0x0, 0x0, 0x0, 0x0, 0xa7, 0xc0, 0xc, 0x0, 0x1c, 0x0, 0x1, 0x0, 0x0, 0x6,
0x5c, 0x0, 0x10, 0x20, 0x1, 0x49, 0x98, 0x0, 0xc, 0xa, 0x6, 0x0, 0x0, 0x0,
0x0, 0x0, 0x2, 0x40, 0x8, 0xc0, 0xc, 0x0, 0x1c, 0x0, 0x1, 0x0, 0x0, 0x6,
0x5c, 0x0, 0x10, 0x20, 0x1, 0x49, 0x98, 0x0, 0x58, 0xc, 0x2, 0x0, 0x0,
0x0,
0x0, 0x0, 0x0, 0x0, 0xa9, 0xc0, 0xc, 0x0, 0x1, 0x0, 0x1, 0x0, 0x0, 0x6,
0x5c, 0x0, 0x4, 0x62, 0x8a, 0xfd, 0x6d, 0xc0, 0xc, 0x0, 0x1, 0x0, 0x1,
0x0,
0x0, 0x6, 0x5c, 0x0, 0x4, 0xce, 0xbe, 0x24, 0x2d, 0xc0, 0xc, 0x0, 0x1,
0x0,
0x1, 0x0, 0x0, 0x6, 0x5c, 0x0, 0x4, 0x62, 0x8b, 0xb4, 0x95, 0xc0, 0xc,
0x0,
0x6, 0x0, 0x1, 0x0, 0x0, 0x6, 0x5c, 0x0, 0x2d, 0xc0, 0x7b, 0xa, 0x68,
0x6f,
0x73, 0x74, 0x6d, 0x61, 0x73, 0x74, 0x65, 0x72, 0x9, 0x79, 0x61, 0x68,
0x6f, 0x6f, 0x2d, 0x69, 0x6e, 0x63, 0xc0, 0x12, 0x78, 0x3a, 0x85, 0x44,
0x0, 0x0, 0xe, 0x10, 0x0, 0x0, 0x1, 0x2c, 0x0, 0x1b, 0xaf, 0x80, 0x0, 0x0,
0x2, 0x58
};
/* www.cisco.com, has no addresses in reply */
static u8 dns_reply_data_initializer[] = {
0x00, 0x01, 0x81, 0x80, 0x00, 0x01, 0x00, 0x01,
0x00, 0x00, 0x00, 0x00, 0x03, 0x77, 0x77, 0x77, 0x05,
0x63, 0x69, 0x73, 0x63, 0x6f, 0x03, 0x63, 0x6f, 0x6d,
0x00, 0x00, 0xff, 0x00, 0x01, 0xc0, 0x0c, 0x00, 0x05,
0x00, 0x01, 0x00, 0x00, 0x0b, 0xd3, 0x00, 0x1a, 0x03,
0x77, 0x77, 0x77, 0x05, 0x63, 0x69, 0x73, 0x63, 0x6f,
0x03, 0x63, 0x6f, 0x6d, 0x06, 0x61, 0x6b, 0x61, 0x64,
0x6e, 0x73, 0x03, 0x6e, 0x65, 0x74, 0x00,
};
#else
/* google.com */
static u8 dns_reply_data_initializer[] =
{ 0x0, 0x0, 0x81, 0x80, 0x0, 0x1, 0x0, 0xe, 0x0, 0x0, 0x0, 0x0, 0x6,
0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x3, 0x63, 0x6f, 0x6d, 0x0, 0x0, 0xff,
0x0, 0x1, 0xc0, 0xc, 0x0, 0x1, 0x0, 0x1, 0x0, 0x0, 0x1, 0x2b, 0x0, 0x4,
0xac, 0xd9, 0x3, 0x2e, 0xc0, 0xc, 0x0, 0x1c, 0x0, 0x1, 0x0, 0x0, 0x1,
0x2b,
0x0, 0x10, 0x26, 0x7, 0xf8, 0xb0, 0x40, 0x4, 0x8, 0xf, 0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x20, 0xe, 0xc0, 0xc, 0x0, 0x2, 0x0, 0x1, 0x0, 0x1, 0x51, 0x7f,
0x0, 0x6, 0x3, 0x6e, 0x73, 0x31, 0xc0, 0xc, 0xc0, 0xc, 0x0, 0x6, 0x0, 0x1,
0x0, 0x0, 0x0, 0x3b, 0x0, 0x22, 0xc0, 0x54, 0x9, 0x64, 0x6e, 0x73, 0x2d,
0x61, 0x64, 0x6d, 0x69, 0x6e, 0xc0, 0xc, 0xa, 0x3d, 0xc7, 0x30, 0x0, 0x0,
0x3, 0x84, 0x0, 0x0, 0x3, 0x84, 0x0, 0x0, 0x7, 0x8, 0x0, 0x0, 0x0, 0x3c,
0xc0, 0xc, 0x0, 0xf, 0x0, 0x1, 0x0, 0x0, 0x2, 0x57, 0x0, 0x11, 0x0, 0x1e,
0x4, 0x61, 0x6c, 0x74, 0x32, 0x5, 0x61, 0x73, 0x70, 0x6d, 0x78, 0x1, 0x6c,
0xc0, 0xc, 0xc0, 0xc, 0x0, 0xf, 0x0, 0x1, 0x0, 0x0, 0x2, 0x57, 0x0, 0x4,
0x0, 0xa, 0xc0, 0x9b, 0xc0, 0xc, 0x0, 0x10, 0x0, 0x1, 0x0, 0x0, 0xe, 0xf,
0x0, 0x24, 0x23, 0x76, 0x3d, 0x73, 0x70, 0x66, 0x31, 0x20, 0x69, 0x6e,
0x63, 0x6c, 0x75, 0x64, 0x65, 0x3a, 0x5f, 0x73, 0x70, 0x66, 0x2e, 0x67,
0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x63, 0x6f, 0x6d, 0x20, 0x7e, 0x61,
0x6c, 0x6c, 0xc0, 0xc, 0x0, 0x2, 0x0, 0x1, 0x0, 0x1, 0x51, 0x7f, 0x0, 0x6,
0x3, 0x6e, 0x73, 0x32, 0xc0, 0xc, 0xc0, 0xc, 0x1, 0x1, 0x0, 0x1, 0x0, 0x1,
0x51, 0x7f, 0x0, 0xf, 0x0, 0x5, 0x69, 0x73, 0x73, 0x75, 0x65, 0x70, 0x6b,
0x69, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0xc0, 0xc, 0x0, 0x2, 0x0, 0x1, 0x0,
0x1, 0x51, 0x7f, 0x0, 0x6, 0x3, 0x6e, 0x73, 0x34, 0xc0, 0xc, 0xc0, 0xc,
0x0, 0xf, 0x0, 0x1, 0x0, 0x0, 0x2, 0x57, 0x0, 0x9, 0x0, 0x28, 0x4, 0x61,
0x6c, 0x74, 0x33, 0xc0, 0x9b, 0xc0, 0xc, 0x0, 0x2, 0x0, 0x1, 0x0, 0x1,
0x51, 0x7f, 0x0, 0x6, 0x3, 0x6e, 0x73, 0x33, 0xc0, 0xc, 0xc0, 0xc, 0x0,
0xf, 0x0, 0x1, 0x0, 0x0, 0x2, 0x57, 0x0, 0x9, 0x0, 0x32, 0x4, 0x61, 0x6c,
0x74, 0x34, 0xc0, 0x9b, 0xc0, 0xc, 0x0, 0xf, 0x0, 0x1, 0x0, 0x0, 0x2,
0x57,
0x0, 0x9, 0x0, 0x14, 0x4, 0x61, 0x6c, 0x74, 0x31, 0xc0, 0x9b
};
#endif
static clib_error_t *
test_dns_fmt_command_fn (vlib_main_t * vm,
unformat_input_t * input, vlib_cli_command_t * cmd)
{
u8 *dns_reply_data = 0;
int verbose = 0;
int rv;
vl_api_dns_resolve_name_reply_t _rm, *rmp = &_rm;
while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
{
if (unformat (input, "verbose %d", &verbose))
;
else if (unformat (input, "verbose"))
verbose = 1;
else
return clib_error_return (0, "unknown input `%U'",
format_unformat_error, input);
}
vec_validate (dns_reply_data, ARRAY_LEN (dns_reply_data_initializer) - 1);
memcpy (dns_reply_data, dns_reply_data_initializer,
ARRAY_LEN (dns_reply_data_initializer));
vlib_cli_output (vm, "%U", format_dns_reply, dns_reply_data, verbose);
memset (rmp, 0, sizeof (*rmp));
rv = vnet_dns_response_to_reply (dns_reply_data, rmp, 0 /* ttl-ptr */ );
switch (rv)
{
case VNET_API_ERROR_NAME_SERVER_NO_ADDRESSES:
vlib_cli_output (vm, "no addresses found...");
break;
default:
vlib_cli_output (vm, "response to reply returned %d", rv);
break;
case 0:
if (rmp->ip4_set)
vlib_cli_output (vm, "ip4 address: %U", format_ip4_address,
(ip4_address_t *) rmp->ip4_address);
if (rmp->ip6_set)
vlib_cli_output (vm, "ip6 address: %U", format_ip6_address,
(ip6_address_t *) rmp->ip6_address);
break;
}
vec_free (dns_reply_data);
return 0;
}
/* *INDENT-OFF* */
VLIB_CLI_COMMAND (test_dns_fmt_command) =
{
.path = "test dns format",
.short_help = "test dns format",
.function = test_dns_fmt_command_fn,
};
/* *INDENT-ON* */
static clib_error_t *
test_dns_unfmt_command_fn (vlib_main_t * vm,
unformat_input_t * input, vlib_cli_command_t * cmd)
{
u8 *dns_reply_data = 0;
int verbose = 0;
int reply_set = 0;
while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
{
if (unformat (input, "verbose %d", &verbose))
;
else if (unformat (input, "verbose"))
verbose = 1;
else if (unformat (input, "%U", unformat_dns_reply, &dns_reply_data))
reply_set = 1;
else
return clib_error_return (0, "unknown input `%U'",
format_unformat_error, input);
}
if (reply_set == 0)
return clib_error_return (0, "dns data not set...");
vlib_cli_output (vm, "%U", format_dns_reply, dns_reply_data, verbose);
vec_free (dns_reply_data);
return 0;
}
/* *INDENT-OFF* */
VLIB_CLI_COMMAND (test_dns_unfmt_command) =
{
.path = "test dns unformat",
.short_help = "test dns unformat <name> [ip4][ip6]",
.function = test_dns_unfmt_command_fn,
};
/* *INDENT-ON* */
static clib_error_t *
test_dns_expire_command_fn (vlib_main_t * vm,
unformat_input_t * input,
vlib_cli_command_t * cmd)
{
dns_main_t *dm = &dns_main;
u8 *name;
uword *p;
clib_error_t *e;
dns_cache_entry_t *ep;
if (unformat (input, "%v", &name))
{
vec_add1 (name, 0);
_vec_len (name) -= 1;
}
dns_cache_lock (dm);
p = hash_get_mem (dm->cache_entry_by_name, name);
if (!p)
{
dns_cache_unlock (dm);
e = clib_error_return (0, "%s is not in the cache...", name);
vec_free (name);
return e;
}
ep = pool_elt_at_index (dm->entries, p[0]);
ep->expiration_time = 0;
return 0;
}
/* *INDENT-OFF* */
VLIB_CLI_COMMAND (test_dns_expire_command) =
{
.path = "test dns expire",
.short_help = "test dns expire <name>",
.function = test_dns_expire_command_fn,
};
/* *INDENT-ON* */
#endif
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/