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authorDave Barach <dave@barachs.net>2017-10-10 17:53:14 -0400
committerFlorin Coras <florin.coras@gmail.com>2017-10-13 20:20:09 +0000
commit6545716c073c88ad86458620c6dbc59ba1cd00bb (patch)
tree2bd8b7d9cd0e221669081aba27786e1ce5eee964 /src/vnet/dns
parent7e550693dffd368b9dd8e0397674cfc4d10f9579 (diff)
VPP-1027: DNS name resolver
This patch is a plausible first-cut, suitable for initial testing by vcl (host stack client library). Main features; - recursive name resolution - multiple ip4/ip6 name servers - cache size limit enforcement - currently limited to 65K - ttl / aging - static mapping support - show / clear / debug CLI commands Binary APIs provided for the following: - add/delete name servers - enable/disable the name cache - resolve a name To Do list: - Respond to ip4/ip6 client DNS requests (vs. binary API requests) - Perf / scale tuning - map pending transaction ids to pool indices, so the cache can (greatly) exceed 65K entries - Security improvements - Use unpredictable dns transaction IDs, related to previous item - Make sure that response-packet src ip addresses match the server - Add binary APIs - deliver raw response data to clients - control recursive name resolution - Documentation Change-Id: I48c373d5c05d7108ccd814d4055caf8c75ca10b7 Signed-off-by: Dave Barach <dave@barachs.net>
Diffstat (limited to 'src/vnet/dns')
-rw-r--r--src/vnet/dns/dns.api66
-rw-r--r--src/vnet/dns/dns.c2114
-rw-r--r--src/vnet/dns/dns.h149
-rw-r--r--src/vnet/dns/dns_packet.h154
-rw-r--r--src/vnet/dns/reply_node.c214
-rw-r--r--src/vnet/dns/resolver_process.c243
6 files changed, 2940 insertions, 0 deletions
diff --git a/src/vnet/dns/dns.api b/src/vnet/dns/dns.api
new file mode 100644
index 00000000000..55574458ddd
--- /dev/null
+++ b/src/vnet/dns/dns.api
@@ -0,0 +1,66 @@
+/*
+ * 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.
+ */
+
+vl_api_version 1.0.0
+
+/** \brief enable/disable name resolution
+
+ @param client_index - opaque cookie to identify the sender
+ @param context - sender context, to match reply w/ request
+ @param is_enable - 1 = enable, 0 = disable
+*/
+autoreply define dns_enable_disable {
+ u32 client_index;
+ u32 context;
+ u8 enable;
+};
+
+/** \brief add or delete an upstream name server
+
+ @param client_index - opaque cookie to identify the sender
+ @param context - sender context, to match reply w/ request
+ @param is_ip6 - an ip6 name server
+ @param is_add - add = 1, delete = 0
+ @param server_address - server ip address
+*/
+autoreply define dns_name_server_add_del {
+ u32 client_index;
+ u32 context;
+ u8 is_ip6;
+ u8 is_add;
+ u8 server_address[16];
+};
+
+/** \brief DNS name resolution request
+
+ @param client_index - opaque cookie to identify the sender
+ @param context - sender context, to match reply w/ request
+ @param name - the name to resolve
+*/
+define dns_resolve_name {
+ u32 client_index;
+ u32 context;
+ u8 name[128];
+ };
+
+define dns_resolve_name_reply {
+ u32 context;
+ i32 retval;
+ u8 ip4_set;
+ u8 ip6_set;
+ u8 ip4_address[4];
+ u8 ip6_address[16];
+};
+
diff --git a/src/vnet/dns/dns.c b/src/vnet/dns/dns.c
new file mode 100644
index 00000000000..90079e17e99
--- /dev/null
+++ b/src/vnet/dns/dns.c
@@ -0,0 +1,2114 @@
+/*
+ * 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;
+
+ /* 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;
+
+ 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);
+ 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))
+ {
+ clib_warning ("Re-resolve %s", name);
+ /* Yes, kill it... */
+ vnet_dns_delete_entry_by_index_nolock (dm, p[0]);
+ goto re_resolve;
+ }
+
+ /* Note: caller must drop the lock! */
+ *retp = ep;
+ return (0);
+ }
+ }
+
+ 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;
+ }
+ }
+
+re_resolve:
+ /* 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;
+}
+
+/**
+ * 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, dns_cache_entry_t * ep,
+ 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;
+
+ 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++;
+ }
+ qp = (dns_query_t *) pos;
+ pos += sizeof (*qp);
+ }
+ 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;
+
+ /* Crap. Chase the CNAME name chain. */
+
+ cname = labels_to_name (rr->rdata, reply, &pos2);
+ request = name_to_labels (cname);
+ vec_free (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 (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;
+
+ vec_free (ep->dns_request);
+ ep->dns_request = request;
+ ep->retry_timer = vlib_time_now (dm->vlib_main) + 2.0;
+ ep->retry_count = 0;
+
+ /*
+ * Enable this to watch recursive resolution happen...
+ * fformat (stdout, "%U", format_dns_reply, request, 2);
+ */
+
+ 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);
+
+ vec_free (reply);
+ 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;
+ break;
+ }
+ pos += len;
+ len = *pos++;
+ }
+ curpos = pos;
+ }
+
+ 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_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 = " ";
+
+ 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 = " ";
+
+ 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');
+ }));
+ /* *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* */
+#endif
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/vnet/dns/dns.h b/src/vnet/dns/dns.h
new file mode 100644
index 00000000000..5da26156f6c
--- /dev/null
+++ b/src/vnet/dns/dns.h
@@ -0,0 +1,149 @@
+/*
+ * 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.
+ */
+
+#ifndef included_dns_h
+#define included_dns_h
+
+#include <vppinfra/time.h>
+#include <vppinfra/cache.h>
+#include <vppinfra/error.h>
+
+#include <vppinfra/hash.h>
+#include <vnet/dns/dns_packet.h>
+#include <vnet/ip/ip.h>
+
+typedef struct
+{
+ /** flags */
+ volatile u8 flags;
+
+ /** The name in "normal human being" notation, e.g. www.foobar.com */
+ u8 *name;
+
+ /** Expiration time */
+ f64 expiration_time;
+
+ /** Cached dns request, for sending retries */
+ u8 *dns_request;
+
+ /** Retry parameters */
+ int retry_count;
+ int server_rotor;
+ int server_af;
+ f64 retry_timer;
+
+ /** Cached dns response */
+ u8 *dns_response;
+
+ /** Clients awaiting responses */
+ u32 *api_clients_to_notify;
+ u32 *api_client_contexts;
+ ip4_address_t *ip4_peers_to_notify;
+ ip6_address_t *ip6_peers_to_notify;
+} dns_cache_entry_t;
+
+#define DNS_CACHE_ENTRY_FLAG_VALID (1<<0) /**< we have Actual Data */
+#define DNS_CACHE_ENTRY_FLAG_STATIC (1<<1) /**< static entry */
+
+#define DNS_RETRIES_PER_SERVER 3
+
+#define DNS_RESOLVER_EVENT_RESOLVED 1
+#define DNS_RESOLVER_EVENT_PENDING 2
+
+
+typedef struct
+{
+ /** Pool of cache entries */
+ dns_cache_entry_t *entries;
+
+ /** Pool indices of unresolved entries */
+ u32 *unresolved_entries;
+
+ /** Find cached record by name */
+ uword *cache_entry_by_name;
+ uword *cache_lock;
+
+ /** enable / disable flag */
+ int is_enabled;
+
+ /** upstream name servers, e.g. 8.8.8.8 */
+ ip4_address_t *ip4_name_servers;
+ ip6_address_t *ip6_name_servers;
+
+ /** config parameters */
+ u32 name_cache_size;
+ u32 max_ttl_in_seconds;
+ u32 random_seed;
+
+ /* convenience */
+ vlib_main_t *vlib_main;
+ vnet_main_t *vnet_main;
+} dns_main_t;
+
+extern dns_main_t dns_main;
+
+extern vlib_node_registration_t dns46_reply_node;
+extern vlib_node_registration_t dns_resolver_node;
+
+#define foreach_dns46_reply_error \
+_(PROCESSED, "DNS reply pkts processed") \
+_(NO_ELT, "No DNS pool element") \
+_(FORMAT_ERROR, "DNS format errors") \
+_(TEST_DROP, "DNS reply pkt dropped for test purposes")
+
+typedef enum
+{
+#define _(sym,str) DNS46_REPLY_ERROR_##sym,
+ foreach_dns46_reply_error
+#undef _
+ DNS46_REPLY_N_ERROR,
+} dns46_reply_error_t;
+
+void vnet_send_dns_request (dns_main_t * dm, dns_cache_entry_t * ep);
+int vnet_dns_cname_indirection_nolock (dns_main_t * dm,
+ dns_cache_entry_t * ep, u8 * reply);
+int vnet_dns_delete_entry_by_index_nolock (dns_main_t * dm, u32 index);
+
+format_function_t format_dns_reply;
+
+static inline void
+dns_cache_lock (dns_main_t * dm)
+{
+ if (dm->cache_lock)
+ {
+ while (__sync_lock_test_and_set (dm->cache_lock, 1))
+ ;
+ }
+}
+
+static inline void
+dns_cache_unlock (dns_main_t * dm)
+{
+ if (dm->cache_lock)
+ {
+ CLIB_MEMORY_BARRIER ();
+ *dm->cache_lock = 0;
+ }
+}
+
+#endif /* included_dns_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/vnet/dns/dns_packet.h b/src/vnet/dns/dns_packet.h
new file mode 100644
index 00000000000..e0ea8fe2706
--- /dev/null
+++ b/src/vnet/dns/dns_packet.h
@@ -0,0 +1,154 @@
+/*
+ * Copyright (c) 2015 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.
+ */
+
+#ifndef included_dns_packet_h
+#define included_dns_packet_h
+
+/**
+ * DNS packet header format
+ */
+
+/* *INDENT-OFF* */
+typedef CLIB_PACKED (struct {
+ u16 id; /**< transaction ID */
+ u16 flags; /**< flags */
+ u16 qdcount; /**< number of questions */
+ u16 anscount; /**< number of answers */
+ u16 nscount; /**< number of name servers */
+ u16 arcount; /**< number of additional records */
+}) dns_header_t;
+/* *INDENT-ON* */
+
+#define DNS_RCODE_MASK (0xf)
+#define DNS_RCODE_NO_ERROR 0
+#define DNS_RCODE_FORMAT_ERROR 1
+#define DNS_RCODE_SERVER_FAILURE 2
+#define DNS_RCODE_NAME_ERROR 3
+#define DNS_RCODE_NOT_IMPLEMENTED 4
+#define DNS_RCODE_REFUSED 5
+
+#define DNS_RA (1<<7) /**< recursion available */
+#define DNS_RD (1<<8) /**< recursion desired */
+#define DNS_TC (1<<9) /**< truncation */
+#define DNS_AA (1<<10) /**< authoritative answer */
+#define DNS_OPCODE_MASK (0xf<<11) /**< opcode mask */
+#define DNS_OPCODE_QUERY (0<<11) /**< standard query */
+#define DNS_OPCODE_IQUERY (1<<11) /**< inverse query (deprecated) */
+#define DNS_OPCODE_STATUS (2<<11) /**< server status */
+#define DNS_QR (1<<15) /**< query=0, response=1 */
+
+
+/*
+ * Note: in DNS-land, www.foobar.com is encoded as three "labels,"
+ * each of which amount to a 1 octet length followed by up to 63
+ * octets of name. Don't forget to add a "null root label" after the last
+ * real one, or the poor slob trying to parse the name will have
+ * no chance whatsoever.
+ *
+ * All RRs have the same top level format shown below:
+ *
+ * 1 1 1 1 1 1
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * | |
+ * / /
+ * / NAME /
+ * | |
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * | TYPE |
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * | CLASS |
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * | TTL |
+ * | |
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * | RDLENGTH |
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--|
+ * / RDATA /
+ * / /
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ *
+ *
+ * DNS "questions" have the following format:
+ *
+ * 1 1 1 1 1 1
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * | |
+ * / QNAME /
+ * / /
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * | QTYPE |
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * | QCLASS |
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ */
+
+/**
+ * DNS "question" fixed header.
+ */
+/* *INDENT-OFF* */
+typedef CLIB_PACKED (struct {
+ u16 type; /**< record type requested */
+ u16 class; /**< class, 1 = internet */
+}) dns_query_t;
+/* *INDENT-ON* */
+
+/**
+ * DNS RR fixed header.
+ */
+/* *INDENT-OFF* */
+typedef CLIB_PACKED (struct {
+ u16 type; /**< record type */
+ u16 class; /**< class, 1 = internet */
+ u32 ttl; /**< time to live, in seconds */
+ u16 rdlength;
+ /**< length of r */
+ u8 rdata[0];
+}) dns_rr_t;
+/* *INDENT-ON* */
+
+/*
+ * There are quite a number of DNS record types
+ * Feel free to add as needed
+ */
+#define foreach_dns_type \
+_(A, 1) /**< ip4 host address */ \
+_(AAAA, 28) /**< ip6 host address */ \
+_(ALL, 255) /**< all available data */ \
+_(TEXT, 16) /**< a text string */ \
+_(NAMESERVER, 2) /**< a nameserver */ \
+_(CNAME, 5) /**< a CNAME (alias) */ \
+_(MAIL_EXCHANGE, 15) /**< a mail exchange */
+
+typedef enum
+{
+#define _(name,value) DNS_TYPE_##name = value,
+ foreach_dns_type
+#undef _
+} dns_type_t;
+
+#define DNS_CLASS_IN 1 /**< The Internet */
+
+
+#endif /* included_dns_packet_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/vnet/dns/reply_node.c b/src/vnet/dns/reply_node.c
new file mode 100644
index 00000000000..e045ba8cda4
--- /dev/null
+++ b/src/vnet/dns/reply_node.c
@@ -0,0 +1,214 @@
+/*
+ * 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 <vlib/vlib.h>
+#include <vnet/vnet.h>
+
+vlib_node_registration_t dns46_reply_node;
+
+typedef struct
+{
+ u32 pool_index;
+ u32 disposition;
+} dns46_reply_trace_t;
+
+/* packet trace format function */
+static u8 *
+format_dns46_reply_trace (u8 * s, va_list * args)
+{
+ CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+ CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+ dns46_reply_trace_t *t = va_arg (*args, dns46_reply_trace_t *);
+
+ s = format (s, "DNS46_REPLY: pool index %d, disposition %d",
+ t->pool_index, t->disposition);
+ return s;
+}
+
+vlib_node_registration_t dns46_reply_node;
+
+static char *dns46_reply_error_strings[] = {
+#define _(sym,string) string,
+ foreach_dns46_reply_error
+#undef _
+};
+
+typedef enum
+{
+ DNS46_REPLY_NEXT_DROP,
+ DNS46_REPLY_N_NEXT,
+} dns46_reply_next_t;
+
+static uword
+dns46_reply_node_fn (vlib_main_t * vm,
+ vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+ u32 n_left_from, *from, *to_next;
+ dns46_reply_next_t next_index;
+
+ from = vlib_frame_vector_args (frame);
+ n_left_from = frame->n_vectors;
+ next_index = node->cached_next_index;
+
+ while (n_left_from > 0)
+ {
+ u32 n_left_to_next;
+
+ vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+#if 0
+ while (n_left_from >= 4 && n_left_to_next >= 2)
+ {
+ u32 next0 = DNS46_REPLY_NEXT_INTERFACE_OUTPUT;
+ u32 next1 = DNS46_REPLY_NEXT_INTERFACE_OUTPUT;
+ u32 sw_if_index0, sw_if_index1;
+ u8 tmp0[6], tmp1[6];
+ ethernet_header_t *en0, *en1;
+ u32 bi0, bi1;
+ vlib_buffer_t *b0, *b1;
+
+ /* Prefetch next iteration. */
+ {
+ vlib_buffer_t *p2, *p3;
+
+ p2 = vlib_get_buffer (vm, from[2]);
+ p3 = vlib_get_buffer (vm, from[3]);
+
+ vlib_prefetch_buffer_header (p2, LOAD);
+ vlib_prefetch_buffer_header (p3, LOAD);
+
+ CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
+ CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
+ }
+
+ /* speculatively enqueue b0 and b1 to the current next frame */
+ to_next[0] = bi0 = from[0];
+ to_next[1] = bi1 = from[1];
+ from += 2;
+ to_next += 2;
+ n_left_from -= 2;
+ n_left_to_next -= 2;
+
+ b0 = vlib_get_buffer (vm, bi0);
+ b1 = vlib_get_buffer (vm, bi1);
+
+ /* $$$$$ End of processing 2 x packets $$$$$ */
+
+ if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
+ {
+ if (b0->flags & VLIB_BUFFER_IS_TRACED)
+ {
+ dns46_reply_trace_t *t =
+ vlib_add_trace (vm, node, b0, sizeof (*t));
+ t->sw_if_index = sw_if_index0;
+ t->next_index = next0;
+ }
+ if (b1->flags & VLIB_BUFFER_IS_TRACED)
+ {
+ dns46_reply_trace_t *t =
+ vlib_add_trace (vm, node, b1, sizeof (*t));
+ t->sw_if_index = sw_if_index1;
+ t->next_index = next1;
+ }
+ }
+
+ /* verify speculative enqueues, maybe switch current next frame */
+ vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
+ to_next, n_left_to_next,
+ bi0, bi1, next0, next1);
+ }
+#endif
+
+ while (n_left_from > 0 && n_left_to_next > 0)
+ {
+ u32 bi0;
+ vlib_buffer_t *b0;
+ u32 next0 = DNS46_REPLY_NEXT_DROP;
+ dns_header_t *d0;
+ u32 pool_index0;
+ u32 error0;
+ u8 *resp0 = 0;
+
+ /* speculatively enqueue b0 to the current next frame */
+ bi0 = from[0];
+ to_next[0] = bi0;
+ from += 1;
+ to_next += 1;
+ n_left_from -= 1;
+
+ n_left_to_next -= 1;
+
+ b0 = vlib_get_buffer (vm, bi0);
+ d0 = vlib_buffer_get_current (b0);
+
+ pool_index0 = clib_host_to_net_u16 (d0->id);
+
+ /* Save the reply */
+ vec_validate (resp0, vlib_buffer_length_in_chain (vm, b0) - 1);
+ clib_memcpy (resp0, d0, vlib_buffer_length_in_chain (vm, b0));
+
+ /*
+ * Deal with everything in process ctx on the main thread
+ */
+ vlib_process_signal_event_mt (vm, dns_resolver_node.index,
+ DNS_RESOLVER_EVENT_RESOLVED,
+ (uword) resp0);
+ error0 = DNS46_REPLY_ERROR_PROCESSED;
+
+ b0->error = node->errors[error0];
+
+ if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
+ && (b0->flags & VLIB_BUFFER_IS_TRACED)))
+ {
+ dns46_reply_trace_t *t =
+ vlib_add_trace (vm, node, b0, sizeof (*t));
+ t->disposition = error0;
+ t->pool_index = pool_index0;
+ }
+
+ /* verify speculative enqueue, maybe switch current next frame */
+ vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+ to_next, n_left_to_next,
+ bi0, next0);
+ }
+
+ vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+ }
+
+ return frame->n_vectors;
+}
+
+VLIB_REGISTER_NODE (dns46_reply_node) =
+{
+ .function = dns46_reply_node_fn,.name = "dns46_reply",.vector_size =
+ sizeof (u32),.format_trace = format_dns46_reply_trace,.type =
+ VLIB_NODE_TYPE_INTERNAL,.n_errors =
+ ARRAY_LEN (dns46_reply_error_strings),.error_strings =
+ dns46_reply_error_strings,.n_next_nodes = DNS46_REPLY_N_NEXT,
+ /* edit / add dispositions here */
+ .next_nodes =
+ {
+ [DNS46_REPLY_NEXT_DROP] = "error-drop",}
+,};
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/vnet/dns/resolver_process.c b/src/vnet/dns/resolver_process.c
new file mode 100644
index 00000000000..91e5cef1bcd
--- /dev/null
+++ b/src/vnet/dns/resolver_process.c
@@ -0,0 +1,243 @@
+/*
+ * 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:
+ */