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);
+ vec_free (ep->pending_requests);
}));
/* *INDENT-ON* */
{
vlib_thread_main_t *tm = &vlib_thread_main;
u32 n_vlib_mains = tm->n_vlib_mains;
+ vlib_main_t *vm = dm->vlib_main;
if (is_enable)
{
&& (vec_len (dm->ip6_name_servers) == 0))
return VNET_API_ERROR_NO_NAME_SERVERS;
+ if (dm->udp_ports_registered == 0)
+ {
+ 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 */ );
+
+ 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 */ );
+
+ dm->udp_ports_registered = 1;
+ }
+
if (dm->cache_entry_by_name == 0)
{
if (n_vlib_mains > 1)
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)
+void
+vnet_dns_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);
{
clib_warning
("route to %U exists, fei %d, get_resolving_interface returned"
- " ~0", fei, format_ip4_address, &prefix.fp_addr);
+ " ~0", format_ip4_address, &prefix.fp_addr, fei);
return;
}
/* *INDENT-OFF* */
- foreach_ip_interface_address(lm4, ia, sw_if_index, 1 /* honor unnummbered */,
+ foreach_ip_interface_address(lm4, ia, sw_if_index, 1 /* honor unnumbered */,
({
src_address = ip_interface_address_get_address (lm4, ia);
goto found_src_address;
vnet_buffer (b)->sw_if_index[VLIB_TX] = 0; /* default VRF for now */
ip = vlib_buffer_get_current (b);
- memset (ip, 0, sizeof (*ip));
+ clib_memset (ip, 0, sizeof (*ip));
udp = (udp_header_t *) (ip + 1);
- memset (udp, 0, sizeof (*udp));
+ clib_memset (udp, 0, sizeof (*udp));
dns_request = (u8 *) (udp + 1);
ep->retry_timer = now + 2.0;
}
-static void
-send_dns6_request (dns_main_t * dm,
- dns_cache_entry_t * ep, ip6_address_t * server)
+void
+vnet_dns_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);
sw_if_index = fib_entry_get_resolving_interface (fei);
/* *INDENT-OFF* */
- foreach_ip_interface_address(lm6, ia, sw_if_index, 1 /* honor unnummbered */,
+ foreach_ip_interface_address(lm6, ia, sw_if_index, 1 /* honor unnumbered */,
({
src_address = ip_interface_address_get_address (lm6, ia);
goto found_src_address;
VLIB_BUFFER_TOTAL_LENGTH_VALID | VNET_BUFFER_F_LOCALLY_ORIGINATED;
ip = vlib_buffer_get_current (b);
- memset (ip, 0, sizeof (*ip));
+ clib_memset (ip, 0, sizeof (*ip));
udp = (udp_header_t *) (ip + 1);
- memset (udp, 0, sizeof (*udp));
+ clib_memset (udp, 0, sizeof (*udp));
dns_request = (u8 *) (udp + 1);
* 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)
+vnet_dns_labels_to_name (u8 * label, u8 * full_text, u8 ** parse_from_here)
{
u8 *reply = 0;
u16 offset;
dns_header_t *h;
dns_query_t *qp;
u16 tmp;
- u8 *request;
+ u8 *request, *name_copy;
u32 qp_offset;
+ /* This can easily happen if sitting in GDB, etc. */
+ if (ep->flags & DNS_CACHE_ENTRY_FLAG_VALID || ep->server_fails > 1)
+ return;
+
/* Construct the dns request, if we haven't been here already */
if (vec_len (ep->dns_request) == 0)
{
* per label is 63, enforce that.
*/
request = name_to_labels (ep->name);
+ name_copy = vec_dup (request);
qp_offset = vec_len (request);
+ /*
+ * At least when testing against "known good" DNS servers:
+ * it turns out that sending 2x requests - one for an A-record
+ * and another for a AAAA-record - seems to work better than
+ * sending a DNS_TYPE_ALL request.
+ */
+
/* Add space for the query header */
- vec_validate (request, qp_offset + sizeof (dns_query_t) - 1);
+ vec_validate (request, 2 * qp_offset + 2 * sizeof (dns_query_t) - 1);
qp = (dns_query_t *) (request + qp_offset);
- qp->type = clib_host_to_net_u16 (DNS_TYPE_ALL);
+ qp->type = clib_host_to_net_u16 (DNS_TYPE_A);
+ qp->class = clib_host_to_net_u16 (DNS_CLASS_IN);
+ qp++;
+ clib_memcpy (qp, name_copy, vec_len (name_copy));
+ qp = (dns_query_t *) (((u8 *) qp) + vec_len (name_copy));
+ vec_free (name_copy);
+
+ qp->type = clib_host_to_net_u16 (DNS_TYPE_AAAA);
qp->class = clib_host_to_net_u16 (DNS_CLASS_IN);
/* Punch in space for the dns_header_t */
/* 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->qdcount = clib_host_to_net_u16 (2);
h->nscount = 0;
h->arcount = 0;
{
if (vec_len (dm->ip6_name_servers))
{
- send_dns6_request (dm, ep,
- dm->ip6_name_servers + ep->server_rotor);
+ vnet_dns_send_dns6_request
+ (dm, ep, dm->ip6_name_servers + ep->server_rotor);
goto out;
}
else
}
if (vec_len (dm->ip4_name_servers))
{
- send_dns4_request (dm, ep, dm->ip4_name_servers + ep->server_rotor);
+ vnet_dns_send_dns4_request
+ (dm, ep, dm->ip4_name_servers + ep->server_rotor);
goto out;
}
}
}
if (ep->server_af == 1 /* ip6 */ )
- send_dns6_request (dm, ep, dm->ip6_name_servers + ep->server_rotor);
+ vnet_dns_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);
+ vnet_dns_send_dns4_request
+ (dm, ep, dm->ip4_name_servers + ep->server_rotor);
out:
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++)
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);
+ vec_free (ep->pending_requests);
pool_put (dm->entries, ep);
return 0;
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;
}
pool_get (dm->entries, ep);
- memset (ep, 0, sizeof (*ep));
+ clib_memset (ep, 0, sizeof (*ep));
/* Note: consumes the name vector */
ep->name = name;
return 0;
}
-static int
-dns_resolve_name (dns_main_t * dm,
- u8 * name, u32 client_index, u32 client_context,
- dns_cache_entry_t ** retp)
+int
+vnet_dns_resolve_name (dns_main_t * dm, u8 * name, dns_pending_request_t * t,
+ dns_cache_entry_t ** retp)
{
dns_cache_entry_t *ep;
int rv;
f64 now;
uword *p;
+ dns_pending_request_t *pr;
+ int count;
now = vlib_time_now (dm->vlib_main);
*retp = 0;
dns_cache_lock (dm);
+search_again:
p = hash_get_mem (dm->cache_entry_by_name, name);
if (p)
{
if (((ep->flags & DNS_CACHE_ENTRY_FLAG_STATIC) == 0)
&& (now > ep->expiration_time))
{
- clib_warning ("Re-resolve %s", name);
+ 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... */
- vnet_dns_delete_entry_by_index_nolock (dm, p[0]);
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
+ * by copying the template request
+ */
+ vec_add2 (ep->pending_requests, pr, 1);
+ memcpy (pr, t, sizeof (*pr));
+ 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... */
}
}
-re_resolve:
/* add new hash table entry */
pool_get (dm->entries, ep);
- memset (ep, 0, sizeof (*ep));
+ clib_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);
+ vec_add2 (ep->pending_requests, pr, 1);
+
+ pr->request_type = t->request_type;
+
+ /* Remember details so we can reply later... */
+ if (t->request_type == DNS_API_PENDING_NAME_TO_IP ||
+ t->request_type == DNS_API_PENDING_IP_TO_NAME)
+ {
+ pr->client_index = t->client_index;
+ pr->client_context = t->client_context;
+ }
+ else
+ {
+ pr->client_index = ~0;
+ pr->is_ip6 = t->is_ip6;
+ pr->dst_port = t->dst_port;
+ pr->id = t->id;
+ pr->name = t->name;
+ if (t->is_ip6)
+ count = 16;
+ else
+ count = 4;
+ clib_memcpy (pr->dst_address, t->dst_address, count);
+ }
+
vnet_send_dns_request (dm, ep);
dns_cache_unlock (dm);
-
return 0;
}
+#define foreach_notification_to_move \
+_(pending_requests)
+
/**
* 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)
+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;
+ u8 *cname_pos = 0;
int len, i;
u8 *cname = 0;
u8 *request = 0;
+ u8 *name_copy;
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);
case DNS_RCODE_SERVER_FAILURE:
case DNS_RCODE_NOT_IMPLEMENTED:
case DNS_RCODE_REFUSED:
- return 0;
+ return -1;
}
curpos = (u8 *) (h + 1);
pos += len;
len = *pos++;
}
- qp = (dns_query_t *) pos;
- pos += sizeof (*qp);
+ pos += sizeof (dns_query_t);
}
pos2 = pos;
/* expect a pointer chase here for a CNAME record */
else
return 0;
- rr = (dns_rr_t *) pos;
+ /* Walk the answer(s) to see what to do next */
+ for (i = 0; i < clib_net_to_host_u16 (h->anscount); i++)
+ {
+ rr = (dns_rr_t *) pos;
+ switch (clib_net_to_host_u16 (rr->type))
+ {
+ /* Real address record? Done.. */
+ case DNS_TYPE_A:
+ case DNS_TYPE_AAAA:
+ return 0;
+ /*
+ * Maybe chase a CNAME pointer?
+ * It's not unheard-of for name-servers to return
+ * both CNAME and A/AAAA records...
+ */
+ case DNS_TYPE_CNAME:
+ cname_pos = pos;
+ break;
- /* This is a real record, not a CNAME record */
- if (clib_net_to_host_u16 (rr->type) != DNS_TYPE_CNAME)
- return 0;
+ /* Some other junk, e.g. a nameserver... */
+ default:
+ break;
+ }
+ pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
+ /* Skip name... */
+ if ((pos2[0] & 0xc0) == 0xc0)
+ pos += 2;
+ }
+
+ /* Neither a CNAME nor a real address. Try another server */
+ if (cname_pos == 0)
+ {
+ flags &= ~DNS_RCODE_MASK;
+ flags |= DNS_RCODE_NAME_ERROR;
+ h->flags = clib_host_to_net_u16 (flags);
+ return -1;
+ }
- /* Crap. Chase the CNAME name chain. */
+ /* This is a CNAME record, chase the name chain. */
+ pos = cname_pos;
+
+ /* 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 = vnet_dns_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 */
+ if (ep->dns_response)
+ vec_free (ep->dns_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);
+
+ clib_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 _
- cname = labels_to_name (rr->rdata, reply, &pos2);
request = name_to_labels (cname);
- vec_free (cname);
+ name_copy = vec_dup (request);
qp_offset = vec_len (request);
/* Add space for the query header */
- vec_validate (request, qp_offset + sizeof (dns_query_t) - 1);
+ vec_validate (request, 2 * qp_offset + 2 * sizeof (dns_query_t) - 1);
qp = (dns_query_t *) (request + qp_offset);
- qp->type = clib_host_to_net_u16 (DNS_TYPE_ALL);
+ qp->type = clib_host_to_net_u16 (DNS_TYPE_A);
+ qp->class = clib_host_to_net_u16 (DNS_CLASS_IN);
+ clib_memcpy (qp, name_copy, vec_len (name_copy));
+ qp = (dns_query_t *) (((u8 *) qp) + vec_len (name_copy));
+ vec_free (name_copy);
+
+ qp->type = clib_host_to_net_u16 (DNS_TYPE_AAAA);
qp->class = clib_host_to_net_u16 (DNS_CLASS_IN);
/* Punch in space for the dns_header_t */
h = (dns_header_t *) request;
/* Transaction ID = pool index */
- h->id = clib_host_to_net_u16 (ep - dm->entries);
+ 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->qdcount = clib_host_to_net_u16 (2);
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;
+ 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);
*/
- 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);
+ vec_add1 (dm->unresolved_entries, next_ep - dm->entries);
+ vnet_send_dns_request (dm, next_ep);
return (1);
}
dns_rr_t *rr;
int i, limit;
u8 len;
- u8 *curpos, *pos;
+ u8 *curpos, *pos, *pos2;
u16 flags;
u16 rcode;
u32 ttl;
+ int pointer_chase;
h = (dns_header_t *) response;
flags = clib_net_to_host_u16 (h->flags);
for (i = 0; i < limit; i++)
{
- pos = curpos;
+ pos = pos2 = curpos;
+ pointer_chase = 0;
/* Expect pointer chases in the answer section... */
- if ((pos[0] & 0xC0) == 0xC0)
- curpos += 2;
- else
+ if ((pos2[0] & 0xC0) == 0xC0)
{
- len = *pos++;
- while (len)
+ pos = pos2 + 2;
+ pos2 = response + ((pos2[0] & 0x3f) << 8) + pos2[1];
+ pointer_chase = 1;
+ }
+
+ len = *pos2++;
+
+ while (len)
+ {
+ pos2 += len;
+ if ((pos2[0] & 0xc0) == 0xc0)
{
- if ((pos[0] & 0xC0) == 0xC0)
- {
- curpos = pos + 2;
- break;
- }
- pos += len;
- len = *pos++;
+ /*
+ * If we've already done one pointer chase,
+ * do not move the pos pointer.
+ */
+ if (pointer_chase == 0)
+ pos = pos2 + 2;
+ pos2 = response + ((pos2[0] & 0x3f) << 8) + pos2[1];
+ len = *pos2++;
+ pointer_chase = 1;
}
- curpos = pos;
+ else
+ len = *pos2++;
}
- rr = (dns_rr_t *) curpos;
+ if (pointer_chase == 0)
+ pos = pos2;
+
+ rr = (dns_rr_t *) pos;
switch (clib_net_to_host_u16 (rr->type))
{
*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);
+ pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
+ curpos = pos;
}
if ((rmp->ip4_set + rmp->ip6_set) == 0)
return 0;
}
+int
+vnet_dns_response_to_name (u8 * response,
+ vl_api_dns_resolve_ip_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, *pos2;
+ u16 flags;
+ u16 rcode;
+ u8 *name;
+ u32 ttl;
+ u8 *junk __attribute__ ((unused));
+ int name_set = 0;
+ int pointer_chase;
+
+ 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 = pos2 = curpos;
+ pointer_chase = 0;
+
+ /* Expect pointer chases in the answer section... */
+ if ((pos2[0] & 0xC0) == 0xC0)
+ {
+ pos = pos2 + 2;
+ pos2 = response + ((pos2[0] & 0x3f) << 8) + pos2[1];
+ pointer_chase = 1;
+ }
+
+ len = *pos2++;
+
+ while (len)
+ {
+ pos2 += len;
+ if ((pos2[0] & 0xc0) == 0xc0)
+ {
+ /*
+ * If we've already done one pointer chase,
+ * do not move the pos pointer.
+ */
+ if (pointer_chase == 0)
+ pos = pos2 + 2;
+ pos2 = response + ((pos2[0] & 0x3f) << 8) + pos2[1];
+ len = *pos2++;
+ pointer_chase = 1;
+ }
+ else
+ len = *pos2++;
+ }
+
+ if (pointer_chase == 0)
+ pos = pos2;
+
+ rr = (dns_rr_t *) pos;
+
+ switch (clib_net_to_host_u16 (rr->type))
+ {
+ case DNS_TYPE_PTR:
+ name = vnet_dns_labels_to_name (rr->rdata, response, &junk);
+ memcpy (rmp->name, name, vec_len (name));
+ ttl = clib_net_to_host_u32 (rr->ttl);
+ if (min_ttlp)
+ *min_ttlp = ttl;
+ rmp->name[vec_len (name)] = 0;
+ name_set = 1;
+ break;
+ default:
+ break;
+ }
+ /* Might as well stop ASAP */
+ if (name_set == 1)
+ break;
+ pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
+ curpos = pos;
+ }
+
+ if (name_set == 0)
+ return VNET_API_ERROR_NAME_SERVER_NO_SUCH_NAME;
+ 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;
+ dns_pending_request_t _t0, *t0 = &_t0;
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);
+ t0->request_type = DNS_API_PENDING_NAME_TO_IP;
+ t0->client_index = mp->client_index;
+ t0->client_context = mp->context;
+
+ rv = vnet_dns_resolve_name (dm, mp->name, t0, &ep);
/* Error, e.g. not enabled? Tell the user */
if (rv < 0)
dns_cache_unlock (dm);
}
+static void
+vl_api_dns_resolve_ip_t_handler (vl_api_dns_resolve_ip_t * mp)
+{
+ dns_main_t *dm = &dns_main;
+ vl_api_dns_resolve_ip_reply_t *rmp;
+ dns_cache_entry_t *ep;
+ int rv;
+ int i, len;
+ u8 *lookup_name = 0;
+ u8 digit, nybble;
+ dns_pending_request_t _t0, *t0 = &_t0;
+
+ if (mp->is_ip6)
+ {
+ for (i = 15; i >= 0; i--)
+ {
+ digit = mp->address[i];
+ nybble = (digit & 0x0F);
+ if (nybble > 9)
+ vec_add1 (lookup_name, (nybble - 10) + 'a');
+ else
+ vec_add1 (lookup_name, nybble + '0');
+ vec_add1 (lookup_name, '.');
+ nybble = (digit & 0xF0) >> 4;
+ if (nybble > 9)
+ vec_add1 (lookup_name, (nybble - 10) + 'a');
+ else
+ vec_add1 (lookup_name, nybble + '0');
+ vec_add1 (lookup_name, '.');
+ }
+ len = vec_len (lookup_name);
+ vec_validate (lookup_name, len + 8);
+ memcpy (lookup_name + len, "ip6.arpa", 8);
+ }
+ else
+ {
+ for (i = 3; i >= 0; i--)
+ {
+ digit = mp->address[i];
+ lookup_name = format (lookup_name, "%d.", digit);
+ }
+ lookup_name = format (lookup_name, "in-addr.arpa");
+ }
+
+ vec_add1 (lookup_name, 0);
+
+ t0->request_type = DNS_API_PENDING_IP_TO_NAME;
+ t0->client_index = mp->client_index;
+ t0->client_context = mp->context;
+
+ rv = vnet_dns_resolve_name (dm, lookup_name, t0, &ep);
+
+ vec_free (lookup_name);
+
+ /* Error, e.g. not enabled? Tell the user */
+ if (rv < 0)
+ {
+ REPLY_MACRO (VL_API_DNS_RESOLVE_IP_REPLY);
+ return;
+ }
+
+ /* Resolution pending? Don't reply... */
+ if (ep == 0)
+ return;
+
+ /* *INDENT-OFF* */
+ REPLY_MACRO2(VL_API_DNS_RESOLVE_IP_REPLY,
+ ({
+ rv = vnet_dns_response_to_name (ep->dns_response, rmp, 0 /* ttl-ptr */);
+ rmp->retval = clib_host_to_net_u32 (rv);
+ }));
+ /* *INDENT-ON* */
+
+ /*
+ * vnet_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
#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)
+_(DNS_RESOLVE_NAME, dns_resolve_name) \
+_(DNS_RESOLVE_IP, dns_resolve_ip)
static clib_error_t *
dns_api_hookup (vlib_main_t * vm)
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;
}
u8 *pos, *pos2;
dns_rr_t *rr;
int i;
- int initial_pointer_chase = 0;
+ int pointer_chase = 0;
u16 *tp;
+ u16 rrtype_host_byte_order;
pos = pos2 = *curpos;
s = format (s, " ");
/* chase pointer? almost always yes here... */
- if (pos2[0] == 0xc0)
+ if ((pos2[0] & 0xc0) == 0xc0)
{
- pos2 = reply + pos2[1];
- pos += 2;
- initial_pointer_chase = 1;
+ pos = pos2 + 2;
+ pos2 = reply + ((pos2[0] & 0x3f) << 8) + pos2[1];
+ pointer_chase = 1;
}
len = *pos2++;
vec_add1 (s, *pos2);
pos2++;
}
- len = *pos2++;
+ if ((pos2[0] & 0xc0) == 0xc0)
+ {
+ /*
+ * If we've already done one pointer chase,
+ * do not move the pos pointer.
+ */
+ if (pointer_chase == 0)
+ pos = pos2 + 2;
+ pos2 = reply + ((pos2[0] & 0x3f) << 8) + pos2[1];
+ len = *pos2++;
+ pointer_chase = 1;
+ }
+ else
+ len = *pos2++;
if (len)
{
if (verbose > 1)
}
}
- if (initial_pointer_chase == 0)
+ if (pointer_chase == 0)
pos = pos2;
rr = (dns_rr_t *) pos;
+ rrtype_host_byte_order = clib_net_to_host_u16 (rr->type);
- switch (clib_net_to_host_u16 (rr->type))
+ switch (rrtype_host_byte_order)
{
case DNS_TYPE_A:
if (verbose > 1)
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)
{
pos2 = rr->rdata;
/* chase pointer? */
- if (pos2[0] == 0xc0)
- pos2 = reply + pos2[1];
+ if ((pos2[0] & 0xc0) == 0xc0)
+ {
+ pos = pos2 + 2;
+ pos2 = reply + ((pos2[0] & 0x3f) << 8) + pos2[1];
+ }
len = *pos2++;
pos += sizeof (*rr) + clib_net_to_host_u16 (rr->rdlength);
break;
+ case DNS_TYPE_PTR:
case DNS_TYPE_CNAME:
if (verbose > 1)
{
tp = (u16 *) rr->rdata;
- s = format (s, "CNAME: ");
+ if (rrtype_host_byte_order == DNS_TYPE_CNAME)
+ s = format (s, "CNAME: ");
+ else
+ s = format (s, "PTR: ");
pos2 = rr->rdata;
else
ss = " ";
- s = format (s, "%s%s -> %U", ss, ep->name,
- format_dns_reply, ep->dns_response, verbose);
+ 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;
else
ss = " ";
- s = format (s, "%s%s -> %U", ss, ep->name,
- format_dns_reply,
- ep->dns_response,
- verbose);
+ 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;
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->pending_requests));
}
}
else
0x03, 0x63, 0x6f, 0x6d, 0x06, 0x61, 0x6b, 0x61, 0x64,
0x6e, 0x73, 0x03, 0x6e, 0x65, 0x74, 0x00,
};
-#else
+
+/* bind8 (linux widget, w/ nasty double pointer chasees */
+static u8 dns_reply_data_initializer[] = {
+ /* 0 */
+ 0x00, 0x01, 0x81, 0x80, 0x00, 0x01, 0x00, 0x08,
+ /* 8 */
+ 0x00, 0x06, 0x00, 0x06, 0x0a, 0x6f, 0x72, 0x69,
+ /* 16 */
+ 0x67, 0x69, 0x6e, 0x2d, 0x77, 0x77, 0x77, 0x05,
+ /* 24 */
+ 0x63, 0x69, 0x73, 0x63, 0x6f, 0x03, 0x63, 0x6f,
+ /* 32 */
+ 0x6d, 0x00, 0x00, 0xff, 0x00, 0x01, 0x0a, 0x6f,
+ /* 40 */
+ 0x72, 0x69, 0x67, 0x69, 0x6e, 0x2d, 0x77, 0x77,
+ /* 48 */
+ 0x77, 0x05, 0x43, 0x49, 0x53, 0x43, 0x4f, 0xc0,
+
+ /* 56 */
+ 0x1d, 0x00, 0x02, 0x00, 0x01, 0x00, 0x00, 0x05,
+
+ /* 64 */
+ 0x9a, 0x00, 0x18, 0x15, 0x72, 0x63, 0x64,
+ 0x6e, 0x39, 0x2d, 0x31, 0x34, 0x70, 0x2d, 0x64, 0x63,
+ 0x7a, 0x30, 0x35, 0x6e, 0x2d, 0x67, 0x73, 0x73, 0x31,
+ 0xc0, 0x17, 0xc0, 0x26, 0x00, 0x02, 0x00, 0x01, 0x00,
+ 0x00, 0x05, 0x9a, 0x00, 0x1a, 0x17, 0x61, 0x6c, 0x6c,
+ 0x6e, 0x30, 0x31, 0x2d, 0x61, 0x67, 0x30, 0x39, 0x2d,
+ 0x64, 0x63, 0x7a, 0x30, 0x33, 0x6e, 0x2d, 0x67, 0x73,
+ 0x73, 0x31, 0xc0, 0x17, 0xc0, 0x26, 0x00, 0x02, 0x00,
+ 0x01, 0x00, 0x00, 0x05, 0x9a, 0x00, 0x10, 0x0d, 0x72,
+ 0x74, 0x70, 0x35, 0x2d, 0x64, 0x6d, 0x7a, 0x2d, 0x67,
+ 0x73, 0x73, 0x31, 0xc0, 0x17, 0xc0, 0x26, 0x00, 0x02,
+ 0x00, 0x01, 0x00, 0x00, 0x05, 0x9a, 0x00, 0x18, 0x15,
+ 0x6d, 0x74, 0x76, 0x35, 0x2d, 0x61, 0x70, 0x31, 0x30,
+ 0x2d, 0x64, 0x63, 0x7a, 0x30, 0x36, 0x6e, 0x2d, 0x67,
+ 0x73, 0x73, 0x31, 0xc0, 0x17, 0xc0, 0x26, 0x00, 0x02,
+ 0x00, 0x01, 0x00, 0x00, 0x05, 0x9a, 0x00, 0x1b, 0x18,
+ 0x73, 0x6e, 0x67, 0x64, 0x63, 0x30, 0x31, 0x2d, 0x61,
+ 0x62, 0x30, 0x37, 0x2d, 0x64, 0x63, 0x7a, 0x30, 0x31,
+ 0x6e, 0x2d, 0x67, 0x73, 0x73, 0x31, 0xc0, 0x17, 0xc0,
+ 0x26, 0x00, 0x02, 0x00, 0x01, 0x00, 0x00, 0x05, 0x9a,
+ 0x00, 0x1a, 0x17, 0x61, 0x65, 0x72, 0x30, 0x31, 0x2d,
+ 0x72, 0x34, 0x63, 0x32, 0x35, 0x2d, 0x64, 0x63, 0x7a,
+ 0x30, 0x31, 0x6e, 0x2d, 0x67, 0x73, 0x73, 0x31, 0xc0,
+ 0x17, 0xc0, 0x26, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00,
+ 0x00, 0x81, 0x00, 0x04, 0x48, 0xa3, 0x04, 0xa1, 0xc0,
+ 0x26, 0x00, 0x1c, 0x00, 0x01, 0x00, 0x00, 0x00, 0x82,
+ 0x00, 0x10, 0x20, 0x01, 0x04, 0x20, 0x12, 0x01, 0x00,
+ 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0a,
+ 0xc0, 0x0c, 0x00, 0x02, 0x00, 0x01, 0x00, 0x00, 0x05,
+ 0x9a, 0x00, 0x02, 0xc0, 0xf4, 0xc0, 0x0c, 0x00, 0x02,
+ 0x00, 0x01, 0x00, 0x00, 0x05, 0x9a, 0x00, 0x02, 0xc0,
+ 0xcd, 0xc0, 0x0c, 0x00, 0x02, 0x00, 0x01, 0x00, 0x00,
+ 0x05, 0x9a, 0x00, 0x02, 0xc0, 0x8d, 0xc0, 0x0c, 0x00,
+ 0x02, 0x00, 0x01, 0x00, 0x00, 0x05, 0x9a, 0x00, 0x02,
+ 0xc0, 0x43, 0xc0, 0x0c, 0x00, 0x02, 0x00, 0x01, 0x00,
+ 0x00, 0x05, 0x9a, 0x00, 0x02, 0xc0, 0xa9, 0xc0, 0x0c,
+ 0x00, 0x02, 0x00, 0x01, 0x00, 0x00, 0x05, 0x9a, 0x00,
+ 0x02, 0xc0, 0x67, 0xc0, 0x8d, 0x00, 0x01, 0x00, 0x01,
+ 0x00, 0x00, 0x07, 0x08, 0x00, 0x04, 0x40, 0x66, 0xf6,
+ 0x05, 0xc0, 0xa9, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00,
+ 0x07, 0x08, 0x00, 0x04, 0xad, 0x24, 0xe0, 0x64, 0xc0,
+ 0x43, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, 0x07, 0x08,
+ 0x00, 0x04, 0x48, 0xa3, 0x04, 0x1c, 0xc0, 0xf4, 0x00,
+ 0x01, 0x00, 0x01, 0x00, 0x00, 0x07, 0x08, 0x00, 0x04,
+ 0xad, 0x26, 0xd4, 0x6c, 0xc0, 0x67, 0x00, 0x01, 0x00,
+ 0x01, 0x00, 0x00, 0x07, 0x08, 0x00, 0x04, 0xad, 0x25,
+ 0x90, 0x64, 0xc0, 0xcd, 0x00, 0x01, 0x00, 0x01, 0x00,
+ 0x00, 0x07, 0x08, 0x00, 0x04, 0xad, 0x27, 0x70, 0x44,
+};
+
/* google.com */
static u8 dns_reply_data_initializer[] =
{ 0x0, 0x0, 0x81, 0x80, 0x0, 0x1, 0x0, 0xe, 0x0, 0x0, 0x0, 0x0, 0x6,
0x57,
0x0, 0x9, 0x0, 0x14, 0x4, 0x61, 0x6c, 0x74, 0x31, 0xc0, 0x9b
};
+
+#else
+/* www.weatherlink.com */
+static u8 dns_reply_data_initializer[] = {
+ 0x00, 0x00, 0x81, 0x80, 0x00, 0x01, 0x00, 0x01,
+ 0x00, 0x00, 0x00, 0x00, 0x03, 0x77, 0x77, 0x77, 0x0b,
+ 0x77, 0x65, 0x61, 0x74, 0x68, 0x65, 0x72, 0x6c, 0x69,
+ 0x6e, 0x6b, 0x03, 0x63, 0x6f, 0x6d, 0x00, 0x00, 0xff,
+ 0x00, 0x01, 0xc0, 0x0c, 0x00, 0x05, 0x00, 0x01, 0x00,
+ 0x00, 0x0c, 0x9e, 0x00, 0x1f, 0x0e, 0x64, 0x33, 0x6b,
+ 0x72, 0x30, 0x67, 0x75, 0x62, 0x61, 0x31, 0x64, 0x76,
+ 0x77, 0x66, 0x0a, 0x63, 0x6c, 0x6f, 0x75, 0x64, 0x66,
+ 0x72, 0x6f, 0x6e, 0x74, 0x03, 0x6e, 0x65, 0x74, 0x00,
+};
+
#endif
static clib_error_t *
vlib_cli_output (vm, "%U", format_dns_reply, dns_reply_data, verbose);
- memset (rmp, 0, sizeof (*rmp));
+ clib_memset (rmp, 0, sizeof (*rmp));
rv = vnet_dns_response_to_reply (dns_reply_data, rmp, 0 /* ttl-ptr */ );
.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 = 0;
+ uword *p;
+ clib_error_t *e;
+ dns_cache_entry_t *ep;
+
+ if (unformat (input, "%v", &name))
+ {
+ vec_add1 (name, 0);
+ _vec_len (name) -= 1;
+ }
+ else
+ return clib_error_return (0, "no name provided");
+
+ 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
+void
+vnet_send_dns6_reply (dns_main_t * dm, dns_pending_request_t * pr,
+ dns_cache_entry_t * ep, vlib_buffer_t * b0)
+{
+ clib_warning ("Unimplemented...");
+}
+
+
+void
+vnet_send_dns4_reply (dns_main_t * dm, dns_pending_request_t * pr,
+ dns_cache_entry_t * ep, vlib_buffer_t * b0)
+{
+ vlib_main_t *vm = dm->vlib_main;
+ u32 bi = 0;
+ fib_prefix_t prefix;
+ fib_node_index_t fei;
+ u32 sw_if_index, fib_index;
+ 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;
+ ip4_header_t *ip;
+ udp_header_t *udp;
+ dns_header_t *dh;
+ vlib_frame_t *f;
+ u32 *to_next;
+ u8 *dns_response;
+ u8 *reply;
+ vl_api_dns_resolve_name_reply_t _rnr, *rnr = &_rnr;
+ vl_api_dns_resolve_ip_reply_t _rir, *rir = &_rir;
+ u32 ttl, tmp;
+ u32 qp_offset;
+ dns_query_t *qp;
+ dns_rr_t *rr;
+ u8 *rrptr;
+ int is_fail = 0;
+
+ ASSERT (ep && ep->dns_response);
+
+ if (pr->request_type == DNS_PEER_PENDING_NAME_TO_IP)
+ {
+ /* Quick and dirty way to dig up the A-record address. $$ FIXME */
+ clib_memset (rnr, 0, sizeof (*rnr));
+ if (vnet_dns_response_to_reply (ep->dns_response, rnr, &ttl))
+ {
+ /* clib_warning ("response_to_reply failed..."); */
+ is_fail = 1;
+ }
+ if (rnr->ip4_set == 0)
+ {
+ /* clib_warning ("No A-record..."); */
+ is_fail = 1;
+ }
+ }
+ else if (pr->request_type == DNS_PEER_PENDING_IP_TO_NAME)
+ {
+ clib_memset (rir, 0, sizeof (*rir));
+ if (vnet_dns_response_to_name (ep->dns_response, rir, &ttl))
+ {
+ /* clib_warning ("response_to_name failed..."); */
+ is_fail = 1;
+ }
+ }
+ else
+ {
+ clib_warning ("Unknown request type %d", pr->request_type);
+ return;
+ }
+
+ /* Initialize a buffer */
+ if (b0 == 0)
+ {
+ if (vlib_buffer_alloc (vm, &bi, 1) != 1)
+ return;
+ b0 = vlib_get_buffer (vm, bi);
+ }
+
+ if (b0->flags & VLIB_BUFFER_NEXT_PRESENT)
+ vlib_buffer_free_one (vm, b0->next_buffer);
+
+ /*
+ * Reset the buffer. We recycle the DNS request packet in the cache
+ * hit case, and reply immediately from the request node.
+ *
+ * In the resolution-required / deferred case, resetting a freshly-allocated
+ * buffer won't hurt. We hope.
+ */
+ b0->flags |= (VNET_BUFFER_F_LOCALLY_ORIGINATED
+ | VLIB_BUFFER_TOTAL_LENGTH_VALID);
+ b0->current_data = 0;
+ b0->current_length = 0;
+ b0->total_length_not_including_first_buffer = 0;
+ vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0; /* "local0" */
+ vnet_buffer (b0)->sw_if_index[VLIB_TX] = 0; /* default VRF for now */
+
+ /* Find a FIB path to the peer we're trying to answer */
+ clib_memcpy (&prefix.fp_addr.ip4, pr->dst_address, sizeof (ip4_address_t));
+ 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 unnumbered */,
+ ({
+ src_address = ip_interface_address_get_address (lm4, ia);
+ goto found_src_address;
+ }));
+ /* *INDENT-ON* */
+
+ clib_warning ("FIB BUG");
+ return;
+
+found_src_address:
+
+ ip = vlib_buffer_get_current (b0);
+ udp = (udp_header_t *) (ip + 1);
+ dns_response = (u8 *) (udp + 1);
+ clib_memset (ip, 0, sizeof (*ip) + sizeof (*udp));
+
+ /*
+ * 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.
+ */
+ reply = name_to_labels (pr->name);
+ vec_free (pr->name);
+
+ qp_offset = vec_len (reply);
+
+ /* Add space for the query header */
+ vec_validate (reply, qp_offset + sizeof (dns_query_t) - 1);
+
+ qp = (dns_query_t *) (reply + qp_offset);
+
+ if (pr->request_type == DNS_PEER_PENDING_NAME_TO_IP)
+ qp->type = clib_host_to_net_u16 (DNS_TYPE_A);
+ else
+ qp->type = clib_host_to_net_u16 (DNS_TYPE_PTR);
+
+ qp->class = clib_host_to_net_u16 (DNS_CLASS_IN);
+
+ /* Punch in space for the dns_header_t */
+ vec_insert (reply, sizeof (dns_header_t), 0);
+
+ dh = (dns_header_t *) reply;
+
+ /* Transaction ID = pool index */
+ dh->id = pr->id;
+
+ /* Announce that we did a recursive lookup */
+ tmp = DNS_AA | DNS_RA | DNS_RD | DNS_OPCODE_QUERY | DNS_QR;
+ if (is_fail)
+ tmp |= DNS_RCODE_NAME_ERROR;
+ dh->flags = clib_host_to_net_u16 (tmp);
+ dh->qdcount = clib_host_to_net_u16 (1);
+ dh->anscount = (is_fail == 0) ? clib_host_to_net_u16 (1) : 0;
+ dh->nscount = 0;
+ dh->arcount = 0;
+
+ /* If the name resolution worked, cough up an appropriate RR */
+ if (is_fail == 0)
+ {
+ /* Add the answer. First, a name pointer (0xC00C) */
+ vec_add1 (reply, 0xC0);
+ vec_add1 (reply, 0x0C);
+
+ /* Now, add single A-rec RR */
+ if (pr->request_type == DNS_PEER_PENDING_NAME_TO_IP)
+ {
+ vec_add2 (reply, rrptr, sizeof (dns_rr_t) + sizeof (ip4_address_t));
+ rr = (dns_rr_t *) rrptr;
+
+ rr->type = clib_host_to_net_u16 (DNS_TYPE_A);
+ rr->class = clib_host_to_net_u16 (1 /* internet */ );
+ rr->ttl = clib_host_to_net_u32 (ttl);
+ rr->rdlength = clib_host_to_net_u16 (sizeof (ip4_address_t));
+ clib_memcpy (rr->rdata, rnr->ip4_address, sizeof (ip4_address_t));
+ }
+ else
+ {
+ /* Or a single PTR RR */
+ u8 *vecname = format (0, "%s", rir->name);
+ u8 *label_vec = name_to_labels (vecname);
+ vec_free (vecname);
+
+ vec_add2 (reply, rrptr, sizeof (dns_rr_t) + vec_len (label_vec));
+ rr = (dns_rr_t *) rrptr;
+ rr->type = clib_host_to_net_u16 (DNS_TYPE_PTR);
+ rr->class = clib_host_to_net_u16 (1 /* internet */ );
+ rr->ttl = clib_host_to_net_u32 (ttl);
+ rr->rdlength = clib_host_to_net_u16 (vec_len (label_vec));
+ clib_memcpy (rr->rdata, label_vec, vec_len (label_vec));
+ vec_free (label_vec);
+ }
+ }
+ clib_memcpy (dns_response, reply, vec_len (reply));
+
+ /* Set the packet length */
+ b0->current_length = sizeof (*ip) + sizeof (*udp) + vec_len (reply);
+
+ /* IP header */
+ ip->ip_version_and_header_length = 0x45;
+ ip->length = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
+ ip->ttl = 255;
+ ip->protocol = IP_PROTOCOL_UDP;
+ ip->src_address.as_u32 = src_address->as_u32;
+ clib_memcpy (ip->dst_address.as_u8, pr->dst_address,
+ sizeof (ip4_address_t));
+ ip->checksum = ip4_header_checksum (ip);
+
+ /* UDP header */
+ udp->src_port = clib_host_to_net_u16 (UDP_DST_PORT_dns);
+ udp->dst_port = pr->dst_port;
+ udp->length = clib_host_to_net_u16 (sizeof (udp_header_t) +
+ vec_len (reply));
+ udp->checksum = 0;
+ vec_free (reply);
+
+ /* 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);
+}
+
/*
* fd.io coding-style-patch-verification: ON
*
Code Review / vpp.git / blobdiff