src/vnet/dns/request_node.c - fdio/vpp - Gitiles

 /*
  * 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_request_node;

 typedef struct
 {
   u32 pool_index;
   u32 disposition;
 } dns46_request_trace_t;

 /* packet trace format function */
 static u8 *
 format_dns46_request_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_request_trace_t *t = va_arg (*args, dns46_request_trace_t *);

   s = format (s, "DNS46_REPLY: pool index %d, disposition  %d",
 	      t->pool_index, t->disposition);
   return s;
 }

 vlib_node_registration_t dns46_request_node;

 static char *dns46_request_error_strings[] = {
 #define _(sym,string) string,
   foreach_dns46_request_error
 #undef _
 };

 typedef enum
 {
   DNS46_REQUEST_NEXT_DROP,
   DNS46_REQUEST_NEXT_IP_LOOKUP,
   DNS46_REQUEST_NEXT_PUNT,
   DNS46_REQUEST_N_NEXT,
 } dns46_request_next_t;

 static uword
 dns46_request_inline (vlib_main_t * vm,
 		      vlib_node_runtime_t * node, vlib_frame_t * frame,
 		      int is_ip6)
 {
   u32 n_left_from, *from, *to_next;
   dns46_request_next_t next_index;
   dns_main_t *dm = &dns_main;

   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_REQUEST_NEXT_INTERFACE_OUTPUT;
 	  u32 next1 = DNS46_REQUEST_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_request_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_request_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_REQUEST_NEXT_DROP;
 	  u32 error0 = DNS46_REQUEST_ERROR_NONE;
 	  udp_header_t *u0;
 	  dns_header_t *d0;
 	  dns_query_t *q0;
 	  ip4_header_t *ip40 = 0;
 	  ip6_header_t *ip60 = 0;
 	  dns_cache_entry_t *ep0;
 	  dns_pending_request_t _t0, *t0 = &_t0;
 	  u16 flags0;
 	  u32 pool_index0 = ~0;
 	  u8 *name0;
 	  u8 *label0;

 	  /* 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);
 	  u0 = (udp_header_t *) ((u8 *) d0 - sizeof (*u0));

 	  if (PREDICT_FALSE (dm->is_enabled == 0))
 	    {
 	      next0 = DNS46_REQUEST_NEXT_PUNT;
 	      goto done0;
 	    }

 	  if (is_ip6)
 	    {
 	      ip60 = (ip6_header_t *) (((u8 *) u0) - sizeof (ip6_header_t));
 	      next0 = DNS46_REQUEST_NEXT_DROP;
 	      error0 = DNS46_REQUEST_ERROR_UNIMPLEMENTED;
 	      goto done0;
 	    }
 	  else
 	    {
 	      ip40 = (ip4_header_t *) (((u8 *) u0) - sizeof (ip4_header_t));
 	      if (ip40->ip_version_and_header_length != 0x45)
 		{
 		  error0 = DNS46_REQUEST_ERROR_IP_OPTIONS;
 		  goto done0;
 		}
 	    }
 	  /* Parse through the DNS request */
 	  flags0 = clib_net_to_host_u16 (d0->flags);

 	  /* Requests only */
 	  if (flags0 & DNS_QR)
 	    {
 	      next0 = DNS46_REQUEST_NEXT_DROP;
 	      error0 = DNS46_REQUEST_ERROR_BAD_REQUEST;
 	      goto done0;
 	    }
 	  if (clib_net_to_host_u16 (d0->qdcount) != 1)
 	    {
 	      next0 = DNS46_REQUEST_NEXT_DROP;
 	      error0 = DNS46_REQUEST_ERROR_TOO_MANY_REQUESTS;
 	      goto done0;
 	    }

 	  label0 = (u8 *) (d0 + 1);

 	  /*
 	   * vnet_dns_labels_to_name produces a non NULL terminated vector
 	   * vnet_dns_resolve_name expects a C-string.
 	   */
 	  name0 = vnet_dns_labels_to_name (label0, (u8 *) d0, (u8 **) & q0);
 	  vec_add1 (name0, 0);
 	  _vec_len (name0) -= 1;

 	  t0->request_type = DNS_PEER_PENDING_NAME_TO_IP;

 	  /*
 	   * See if this is a reverse lookup. Both ip4 and ip6 reverse
 	   * requests end with ".arpa"
 	   */
 	  if (PREDICT_TRUE (vec_len (name0) > 5))
 	    {
 	      u8 *aptr0 = name0 + vec_len (name0) - 5;

 	      if (!memcmp (aptr0, ".arpa", 5))
 		t0->request_type = DNS_PEER_PENDING_IP_TO_NAME;
 	    }

 	  t0->client_index = ~0;
 	  t0->is_ip6 = is_ip6;
 	  t0->dst_port = u0->src_port;
 	  t0->id = d0->id;
 	  t0->name = name0;
 	  if (is_ip6)
 	    clib_memcpy_fast (t0->dst_address, ip60->src_address.as_u8,
 			      sizeof (ip6_address_t));
 	  else
 	    clib_memcpy_fast (t0->dst_address, ip40->src_address.as_u8,
 			      sizeof (ip4_address_t));

 	  vnet_dns_resolve_name (dm, name0, t0, &ep0);

 	  if (ep0)
 	    {
 	      if (is_ip6)
 		vnet_send_dns6_reply (dm, t0, ep0, b0);
 	      else
 		vnet_send_dns4_reply (dm, t0, ep0, b0);
 	      next0 = DNS46_REQUEST_NEXT_IP_LOOKUP;
 	    }
 	  else
 	    {
 	      error0 = DNS46_REQUEST_ERROR_RESOLUTION_REQUIRED;
 	    }

 	done0:
 	  b0->error = node->errors[error0];

 	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
 			     && (b0->flags & VLIB_BUFFER_IS_TRACED)))
 	    {
 	      dns46_request_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;
 }

 static uword
 dns4_request_node_fn (vlib_main_t * vm,
 		      vlib_node_runtime_t * node, vlib_frame_t * frame)
 {

   return dns46_request_inline (vm, node, frame, 0 /* is_ip6 */ );
 }

 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (dns4_request_node) =
 {
   .function = dns4_request_node_fn,
   .name = "dns4-request",
   .vector_size = sizeof (u32),
   .format_trace = format_dns46_request_trace,
   .type = VLIB_NODE_TYPE_INTERNAL,
   .n_errors = ARRAY_LEN (dns46_request_error_strings),
   .error_strings = dns46_request_error_strings,
   .n_next_nodes = DNS46_REQUEST_N_NEXT,
   .next_nodes = {
     [DNS46_REQUEST_NEXT_DROP] = "error-drop",
     [DNS46_REQUEST_NEXT_PUNT] = "error-punt",
     [DNS46_REQUEST_NEXT_IP_LOOKUP] = "ip4-lookup",
   },
 };
 /* *INDENT-ON* */

 static uword
 dns6_request_node_fn (vlib_main_t * vm,
 		      vlib_node_runtime_t * node, vlib_frame_t * frame)
 {

   return dns46_request_inline (vm, node, frame, 1 /* is_ip6 */ );
 }

 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (dns6_request_node) =
 {
   .function = dns6_request_node_fn,
   .name = "dns6-request",
   .vector_size = sizeof (u32),
   .format_trace = format_dns46_request_trace,
   .type = VLIB_NODE_TYPE_INTERNAL,
   .n_errors = ARRAY_LEN (dns46_request_error_strings),
   .error_strings = dns46_request_error_strings,
   .n_next_nodes = DNS46_REQUEST_N_NEXT,
   .next_nodes = {
     [DNS46_REQUEST_NEXT_DROP] = "error-drop",
     [DNS46_REQUEST_NEXT_PUNT] = "error-punt",
     [DNS46_REQUEST_NEXT_IP_LOOKUP] = "ip6-lookup",
   },
 };
 /* *INDENT-ON* */

 /*
  * fd.io coding-style-patch-verification: ON
  *
  * Local Variables:
  * eval: (c-set-style "gnu")
  * End:
  */
	/*
	* 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_request_node;

	typedef struct
	{
	u32 pool_index;
	u32 disposition;
	} dns46_request_trace_t;

	/* packet trace format function */
	static u8 *
	format_dns46_request_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_request_trace_t t = va_arg (args, dns46_request_trace_t *);

	s = format (s, "DNS46_REPLY: pool index %d, disposition %d",
	t->pool_index, t->disposition);
	return s;
	}

	vlib_node_registration_t dns46_request_node;

	static char *dns46_request_error_strings[] = {
	#define _(sym,string) string,
	foreach_dns46_request_error
	#undef _
	};

	typedef enum
	{
	DNS46_REQUEST_NEXT_DROP,
	DNS46_REQUEST_NEXT_IP_LOOKUP,
	DNS46_REQUEST_NEXT_PUNT,
	DNS46_REQUEST_N_NEXT,
	} dns46_request_next_t;

	static uword
	dns46_request_inline (vlib_main_t * vm,
	vlib_node_runtime_t * node, vlib_frame_t * frame,
	int is_ip6)
	{
	u32 n_left_from, from, to_next;
	dns46_request_next_t next_index;
	dns_main_t *dm = &dns_main;

	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_REQUEST_NEXT_INTERFACE_OUTPUT;
	u32 next1 = DNS46_REQUEST_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_request_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_request_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_REQUEST_NEXT_DROP;
	u32 error0 = DNS46_REQUEST_ERROR_NONE;
	udp_header_t *u0;
	dns_header_t *d0;
	dns_query_t *q0;
	ip4_header_t *ip40 = 0;
	ip6_header_t *ip60 = 0;
	dns_cache_entry_t *ep0;
	dns_pending_request_t _t0, *t0 = &_t0;
	u16 flags0;
	u32 pool_index0 = ~0;
	u8 *name0;
	u8 *label0;

	/* 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);
	u0 = (udp_header_t ) ((u8 ) d0 - sizeof (*u0));

	if (PREDICT_FALSE (dm->is_enabled == 0))
	{
	next0 = DNS46_REQUEST_NEXT_PUNT;
	goto done0;
	}

	if (is_ip6)
	{
	ip60 = (ip6_header_t ) (((u8 ) u0) - sizeof (ip6_header_t));
	next0 = DNS46_REQUEST_NEXT_DROP;
	error0 = DNS46_REQUEST_ERROR_UNIMPLEMENTED;
	goto done0;
	}
	else
	{
	ip40 = (ip4_header_t ) (((u8 ) u0) - sizeof (ip4_header_t));
	if (ip40->ip_version_and_header_length != 0x45)
	{
	error0 = DNS46_REQUEST_ERROR_IP_OPTIONS;
	goto done0;
	}
	}
	/* Parse through the DNS request */
	flags0 = clib_net_to_host_u16 (d0->flags);

	/* Requests only */
	if (flags0 & DNS_QR)
	{
	next0 = DNS46_REQUEST_NEXT_DROP;
	error0 = DNS46_REQUEST_ERROR_BAD_REQUEST;
	goto done0;
	}
	if (clib_net_to_host_u16 (d0->qdcount) != 1)
	{
	next0 = DNS46_REQUEST_NEXT_DROP;
	error0 = DNS46_REQUEST_ERROR_TOO_MANY_REQUESTS;
	goto done0;
	}

	label0 = (u8 *) (d0 + 1);

	/*
	* vnet_dns_labels_to_name produces a non NULL terminated vector
	* vnet_dns_resolve_name expects a C-string.
	*/
	name0 = vnet_dns_labels_to_name (label0, (u8 ) d0, (u8 *) & q0);
	vec_add1 (name0, 0);
	_vec_len (name0) -= 1;

	t0->request_type = DNS_PEER_PENDING_NAME_TO_IP;

	/*
	* See if this is a reverse lookup. Both ip4 and ip6 reverse
	* requests end with ".arpa"
	*/
	if (PREDICT_TRUE (vec_len (name0) > 5))
	{
	u8 *aptr0 = name0 + vec_len (name0) - 5;

	if (!memcmp (aptr0, ".arpa", 5))
	t0->request_type = DNS_PEER_PENDING_IP_TO_NAME;
	}

	t0->client_index = ~0;
	t0->is_ip6 = is_ip6;
	t0->dst_port = u0->src_port;
	t0->id = d0->id;
	t0->name = name0;
	if (is_ip6)
	clib_memcpy_fast (t0->dst_address, ip60->src_address.as_u8,
	sizeof (ip6_address_t));
	else
	clib_memcpy_fast (t0->dst_address, ip40->src_address.as_u8,
	sizeof (ip4_address_t));

	vnet_dns_resolve_name (dm, name0, t0, &ep0);

	if (ep0)
	{
	if (is_ip6)
	vnet_send_dns6_reply (dm, t0, ep0, b0);
	else
	vnet_send_dns4_reply (dm, t0, ep0, b0);
	next0 = DNS46_REQUEST_NEXT_IP_LOOKUP;
	}
	else
	{
	error0 = DNS46_REQUEST_ERROR_RESOLUTION_REQUIRED;
	}

	done0:
	b0->error = node->errors[error0];

	if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
	&& (b0->flags & VLIB_BUFFER_IS_TRACED)))
	{
	dns46_request_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;
	}

	static uword
	dns4_request_node_fn (vlib_main_t * vm,
	vlib_node_runtime_t * node, vlib_frame_t * frame)
	{

	return dns46_request_inline (vm, node, frame, 0 /* is_ip6 */ );
	}

	/* INDENT-OFF */
	VLIB_REGISTER_NODE (dns4_request_node) =
	{
	.function = dns4_request_node_fn,
	.name = "dns4-request",
	.vector_size = sizeof (u32),
	.format_trace = format_dns46_request_trace,
	.type = VLIB_NODE_TYPE_INTERNAL,
	.n_errors = ARRAY_LEN (dns46_request_error_strings),
	.error_strings = dns46_request_error_strings,
	.n_next_nodes = DNS46_REQUEST_N_NEXT,
	.next_nodes = {
	[DNS46_REQUEST_NEXT_DROP] = "error-drop",
	[DNS46_REQUEST_NEXT_PUNT] = "error-punt",
	[DNS46_REQUEST_NEXT_IP_LOOKUP] = "ip4-lookup",
	},
	};
	/* INDENT-ON */

	static uword
	dns6_request_node_fn (vlib_main_t * vm,
	vlib_node_runtime_t * node, vlib_frame_t * frame)
	{

	return dns46_request_inline (vm, node, frame, 1 /* is_ip6 */ );
	}

	/* INDENT-OFF */
	VLIB_REGISTER_NODE (dns6_request_node) =
	{
	.function = dns6_request_node_fn,
	.name = "dns6-request",
	.vector_size = sizeof (u32),
	.format_trace = format_dns46_request_trace,
	.type = VLIB_NODE_TYPE_INTERNAL,
	.n_errors = ARRAY_LEN (dns46_request_error_strings),
	.error_strings = dns46_request_error_strings,
	.n_next_nodes = DNS46_REQUEST_N_NEXT,
	.next_nodes = {
	[DNS46_REQUEST_NEXT_DROP] = "error-drop",
	[DNS46_REQUEST_NEXT_PUNT] = "error-punt",
	[DNS46_REQUEST_NEXT_IP_LOOKUP] = "ip6-lookup",
	},
	};
	/* INDENT-ON */

	/*
	* fd.io coding-style-patch-verification: ON
	*
	* Local Variables:
	* eval: (c-set-style "gnu")
	* End:
	*/