text: /*
   * ipsec_if_in.c : IPSec interface input node
   *
   * 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.
   */
  
  #include <vnet/vnet.h>
  #include <vnet/api_errno.h>
  #include <vnet/ip/ip.h>
  
  #include <vnet/ipsec/ipsec.h>
  #include <vnet/ipsec/esp.h>
  #include <vnet/ipsec/ipsec_io.h>
  #include <vnet/ipsec/ipsec_punt.h>
  
  /* Statistics (not really errors) */
  #define foreach_ipsec_if_input_error				  \
  _(RX, "good packets received")					  \
  _(DISABLED, "ipsec packets received on disabled interface")       \
  _(NO_TUNNEL, "no matching tunnel")                                \
  _(SPI_0, "SPI 0")
  
  static char *ipsec_if_input_error_strings[] = {
  #define _(sym,string) string,
    foreach_ipsec_if_input_error
  #undef _
  };
  
  typedef enum
  {
  #define _(sym,str) IPSEC_IF_INPUT_ERROR_##sym,
    foreach_ipsec_if_input_error
  #undef _
      IPSEC_IF_INPUT_N_ERROR,
  } ipsec_if_input_error_t;
  
  
  typedef struct
  {
    u32 spi;
    u32 seq;
  } ipsec_if_input_trace_t;
  
  static u8 *
  format_ipsec_if_input_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 *);
    ipsec_if_input_trace_t *t = va_arg (*args, ipsec_if_input_trace_t *);
  
    s = format (s, "IPSec: spi %u (0x%08x) seq %u", t->spi, t->spi, t->seq);
    return s;
  }
  
  always_inline u16
  ipsec_ip4_if_no_tunnel (vlib_node_runtime_t * node,
  			vlib_buffer_t * b,
  			const esp_header_t * esp,
  			const ip4_header_t * ip4, u16 offset)
  {
    if (PREDICT_FALSE (0 == esp->spi))
      {
        b->error = node->errors[IPSEC_IF_INPUT_ERROR_SPI_0];
        b->punt_reason =
  	ipsec_punt_reason[(ip4->protocol == IP_PROTOCOL_UDP ?
  			   IPSEC_PUNT_IP4_SPI_UDP_0 : IPSEC_PUNT_IP4_SPI_0)];
      }
    else
      {
        b->error = node->errors[IPSEC_IF_INPUT_ERROR_NO_TUNNEL];
        b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP4_NO_SUCH_TUNNEL];
      }
    vlib_buffer_advance (b, -offset);
    return IPSEC_INPUT_NEXT_PUNT;
  }
  
  always_inline u16
  ipsec_ip6_if_no_tunnel (vlib_node_runtime_t * node,
  			vlib_buffer_t * b,
  			const esp_header_t * esp, u16 offset)
  {
    if (PREDICT_FALSE (0 == esp->spi))
      {
        b->error = node->errors[IPSEC_IF_INPUT_ERROR_NO_TUNNEL];
        b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP6_SPI_0];
      }
    else
      {
        b->error = node->errors[IPSEC_IF_INPUT_ERROR_NO_TUNNEL];
        b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP6_NO_SUCH_TUNNEL];
      }
    vlib_buffer_advance (b, -offset);
    return (IPSEC_INPUT_NEXT_PUNT);
  }
  
  always_inline uword
  ipsec_if_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
  		       vlib_frame_t * from_frame, int is_ip6)
  {
    ipsec_main_t *im = &ipsec_main;
    vnet_main_t *vnm = im->vnet_main;
    vnet_interface_main_t *vim = &vnm->interface_main;
  
    int is_trace = node->flags & VLIB_NODE_FLAG_TRACE;
    u32 thread_index = vm->thread_index;
  
    u32 n_left_from, *from;
    u16 nexts[VLIB_FRAME_SIZE], *next;
    vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
  
    from = vlib_frame_vector_args (from_frame);
    n_left_from = from_frame->n_vectors;
  
    vlib_get_buffers (vm, from, bufs, n_left_from);
    b = bufs;
    next = nexts;
  
    clib_memset_u16 (nexts, im->esp4_decrypt_next_index, n_left_from);
  
    u64 n_bytes = 0, n_packets = 0;
    u32 n_disabled = 0, n_no_tunnel = 0;
  
    u32 last_sw_if_index = ~0;
    u32 last_tunnel_id = ~0;
    ipsec4_tunnel_key_t last_key4;
    ipsec6_tunnel_key_t last_key6;
  
    vlib_combined_counter_main_t *rx_counter;
    vlib_combined_counter_main_t *drop_counter;
  
    if (is_ip6)
      clib_memset (&last_key6, 0xff, sizeof (last_key6));
    else
      last_key4.as_u64 = ~0;
  
    rx_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_RX;
    drop_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_DROP;
  
    while (n_left_from >= 2)
      {
        u32 sw_if_index0, sw_if_index1;
        ip4_header_t *ip40, *ip41;
        ip6_header_t *ip60, *ip61;
        esp_header_t *esp0, *esp1;
        u32 len0, len1;
        u16 buf_adv0, buf_adv1;
        u32 tid0, tid1;
        ipsec_tunnel_if_t *t0, *t1;
        ipsec4_tunnel_key_t key40, key41;
        ipsec6_tunnel_key_t key60, key61;
  
        if (n_left_from >= 4)
  	{
  	  CLIB_PREFETCH (b[2], CLIB_CACHE_LINE_BYTES, STORE);
  	  CLIB_PREFETCH (b[2]->data, CLIB_CACHE_LINE_BYTES, LOAD);
  	  CLIB_PREFETCH (b[3], CLIB_CACHE_LINE_BYTES, STORE);
  	  CLIB_PREFETCH (b[3]->data, CLIB_CACHE_LINE_BYTES, LOAD);
  	}
  
        ip40 =
  	(ip4_header_t *) (b[0]->data + vnet_buffer (b[0])->l3_hdr_offset);
        ip41 =
  	(ip4_header_t *) (b[1]->data + vnet_buffer (b[1])->l3_hdr_offset);
  
        if (is_ip6)
  	{
  	  ip60 = (ip6_header_t *) ip40;
  	  ip61 = (ip6_header_t *) ip41;
  	  esp0 = (esp_header_t *) ((u8 *) ip60 + sizeof (ip6_header_t));
  	  esp1 = (esp_header_t *) ((u8 *) ip61 + sizeof (ip6_header_t));
  	  buf_adv0 = sizeof (ip6_header_t);
  	  buf_adv1 = sizeof (ip6_header_t);
  	}
        else
  	{
  	  /* NAT UDP port 4500 case, don't advance any more */
  	  if (ip40->protocol == IP_PROTOCOL_UDP)
  	    {
  	      esp0 =
  		(esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40) +
  				  sizeof (udp_header_t));
  	      buf_adv0 = 0;
  	    }
  	  else
  	    {
  	      esp0 = (esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40));
  	      buf_adv0 = ip4_header_bytes (ip40);
  	    }
  	  /* NAT UDP port 4500 case, don't advance any more */
  	  if (ip41->protocol == IP_PROTOCOL_UDP)
  	    {
  	      esp1 =
  		(esp_header_t *) ((u8 *) ip41 + ip4_header_bytes (ip41) +
  				  sizeof (udp_header_t));
  	      buf_adv1 = 0;
  	    }
  	  else
  	    {
  	      esp1 = (esp_header_t *) ((u8 *) ip41 + ip4_header_bytes (ip41));
  	      buf_adv1 = ip4_header_bytes (ip41);
  	    }
  	}
  
        vlib_buffer_advance (b[0], buf_adv0);
        vlib_buffer_advance (b[1], buf_adv1);
  
        len0 = vlib_buffer_length_in_chain (vm, b[0]);
        len1 = vlib_buffer_length_in_chain (vm, b[1]);
  
        if (is_ip6)
  	{
  	  key60.remote_ip = ip60->src_address;
  	  key60.spi = esp0->spi;
  
  	  if (memcmp (&key60, &last_key6, sizeof (last_key6)) == 0)
  	    {
  	      tid0 = last_tunnel_id;
  	    }
  	  else
  	    {
  	      uword *p =
  		hash_get_mem (im->ipsec6_if_pool_index_by_key, &key60);
  	      if (p)
  		{
  		  tid0 = p[0];
  		  last_tunnel_id = tid0;
  		  clib_memcpy_fast (&last_key6, &key60, sizeof (key60));
  		}
  	      else
  		{
  		  next[0] =
  		    ipsec_ip6_if_no_tunnel (node, b[0], esp0, buf_adv0);
  		  n_no_tunnel++;
  		  goto pkt1;
  		}
  	    }
  	}
        else			/* !is_ip6 */
  	{
  	  key40.remote_ip = ip40->src_address.as_u32;
  	  key40.spi = esp0->spi;
  
  	  if (key40.as_u64 == last_key4.as_u64)
  	    {
  	      tid0 = last_tunnel_id;
  	    }
  	  else
  	    {
  	      uword *p =
  		hash_get (im->ipsec4_if_pool_index_by_key, key40.as_u64);
  	      if (p)
  		{
  		  tid0 = p[0];
  		  last_tunnel_id = tid0;
  		  last_key4.as_u64 = key40.as_u64;
  		}
  	      else
  		{
  		  next[0] =
  		    ipsec_ip4_if_no_tunnel (node, b[0], esp0, ip40, buf_adv0);
  		  n_no_tunnel++;
  		  goto pkt1;
  		}
  	    }
  	}
  
        t0 = pool_elt_at_index (im->tunnel_interfaces, tid0);
        vnet_buffer (b[0])->ipsec.sad_index = t0->input_sa_index;
  
        if (PREDICT_TRUE (t0->hw_if_index != ~0))
  	{
  	  sw_if_index0 = t0->sw_if_index;
  	  vnet_buffer (b[0])->sw_if_index[VLIB_RX] = sw_if_index0;
  
  	  if (PREDICT_FALSE (!(t0->flags & VNET_HW_INTERFACE_FLAG_LINK_UP)))
  	    {
  	      vlib_increment_combined_counter
  		(drop_counter, thread_index, sw_if_index0, 1, len0);
  	      n_disabled++;
  	      b[0]->error = node->errors[IPSEC_IF_INPUT_ERROR_DISABLED];
  	      next[0] = IPSEC_INPUT_NEXT_DROP;
  	      goto pkt1;
  	    }
  
  	  if (PREDICT_TRUE (sw_if_index0 == last_sw_if_index))
  	    {
  	      n_packets++;
  	      n_bytes += len0;
  	    }
  	  else
  	    {
  	      if (n_packets)
  		{
  		  vlib_increment_combined_counter
  		    (rx_counter, thread_index, last_sw_if_index,
  		     n_packets, n_bytes);
  		}
  
  	      last_sw_if_index = sw_if_index0;
  	      n_packets = 1;
  	      n_bytes = len0;
  	    }
  	}
  
      pkt1:
        if (is_ip6)
  	{
  	  key61.remote_ip = ip61->src_address;
  	  key61.spi = esp1->spi;
  
  	  if (memcmp (&key61, &last_key6, sizeof (last_key6)) == 0)
  	    {
  	      tid1 = last_tunnel_id;
  	    }
  	  else
  	    {
  	      uword *p =
  		hash_get_mem (im->ipsec6_if_pool_index_by_key, &key61);
  	      if (p)
  		{
  		  tid1 = p[0];
  		  last_tunnel_id = tid1;
  		  clib_memcpy_fast (&last_key6, &key61, sizeof (key61));
  		}
  	      else
  		{
  		  next[1] =
  		    ipsec_ip6_if_no_tunnel (node, b[1], esp1, buf_adv1);
  		  n_no_tunnel++;
  		  goto trace1;
  		}
  	    }
  	}
        else			/* !is_ip6 */
  	{
  	  key41.remote_ip = ip41->src_address.as_u32;
  	  key41.spi = esp1->spi;
  
  	  if (key41.as_u64 == last_key4.as_u64)
  	    {
  	      tid1 = last_tunnel_id;
  	    }
  	  else
  	    {
  	      uword *p =
  		hash_get (im->ipsec4_if_pool_index_by_key, key41.as_u64);
  	      if (p)
  		{
  		  tid1 = p[0];
  		  last_tunnel_id = tid1;
  		  last_key4.as_u64 = key41.as_u64;
  		}
  	      else
  		{
  		  next[1] =
  		    ipsec_ip4_if_no_tunnel (node, b[1], esp1, ip41, buf_adv1);
  		  n_no_tunnel++;
  		  goto trace1;
  		}
  	    }
  	}
  
        t1 = pool_elt_at_index (im->tunnel_interfaces, tid1);
        vnet_buffer (b[1])->ipsec.sad_index = t1->input_sa_index;
  
        if (PREDICT_TRUE (t1->hw_if_index != ~0))
  	{
  	  sw_if_index1 = t1->sw_if_index;
  	  vnet_buffer (b[1])->sw_if_index[VLIB_RX] = sw_if_index1;
  
  	  if (PREDICT_FALSE (!(t1->flags & VNET_HW_INTERFACE_FLAG_LINK_UP)))
  	    {
  	      vlib_increment_combined_counter
  		(drop_counter, thread_index, sw_if_index1, 1, len1);
  	      n_disabled++;
  	      b[1]->error = node->errors[IPSEC_IF_INPUT_ERROR_DISABLED];
  	      next[1] = IPSEC_INPUT_NEXT_DROP;
  	      goto trace1;
  	    }
  
  	  if (PREDICT_TRUE (sw_if_index1 == last_sw_if_index))
  	    {
  	      n_packets++;
  	      n_bytes += len1;
  	    }
  	  else
  	    {
  	      if (n_packets)
  		{
  		  vlib_increment_combined_counter
  		    (rx_counter, thread_index, last_sw_if_index,
  		     n_packets, n_bytes);
  		}
  
  	      last_sw_if_index = sw_if_index1;
  	      n_packets = 1;
  	      n_bytes = len1;
  	    }
  	}
  
      trace1:
        if (PREDICT_FALSE (is_trace))
  	{
  	  if (b[0]->flags & VLIB_BUFFER_IS_TRACED)
  	    {
  	      ipsec_if_input_trace_t *tr =
  		vlib_add_trace (vm, node, b[0], sizeof (*tr));
  	      tr->spi = clib_host_to_net_u32 (esp0->spi);
  	      tr->seq = clib_host_to_net_u32 (esp0->seq);
  	    }
  	  if (b[1]->flags & VLIB_BUFFER_IS_TRACED)
  	    {
  	      ipsec_if_input_trace_t *tr =
  		vlib_add_trace (vm, node, b[1], sizeof (*tr));
  	      tr->spi = clib_host_to_net_u32 (esp1->spi);
  	      tr->seq = clib_host_to_net_u32 (esp1->seq);
  	    }
  	}
  
        /* next */
        b += 2;
        next += 2;
        n_left_from -= 2;
      }
    while (n_left_from > 0)
      {
        u32 sw_if_index0;
        ip4_header_t *ip40;
        ip6_header_t *ip60;
        esp_header_t *esp0;
        u32 len0;
        u16 buf_adv0, buf_rewind0;
        u32 tid0;
        ipsec_tunnel_if_t *t0;
        ipsec4_tunnel_key_t key40;
        ipsec6_tunnel_key_t key60;
  
        ip40 =
  	(ip4_header_t *) (b[0]->data + vnet_buffer (b[0])->l3_hdr_offset);
  
        if (is_ip6)
  	{
  	  ip60 = (ip6_header_t *) ip40;
  	  esp0 = (esp_header_t *) ((u8 *) ip60 + sizeof (ip6_header_t));
  	  buf_adv0 = sizeof (ip6_header_t);
  	}
        else
  	{
  	  /* NAT UDP port 4500 case, don't advance any more */
  	  if (ip40->protocol == IP_PROTOCOL_UDP)
  	    {
  	      esp0 =
  		(esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40) +
  				  sizeof (udp_header_t));
  	      buf_adv0 = 0;
  	      buf_rewind0 = ip4_header_bytes (ip40) + sizeof (udp_header_t);
  	    }
  	  else
  	    {
  	      esp0 = (esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40));
  	      buf_rewind0 = buf_adv0 = ip4_header_bytes (ip40);
  	    }
  	}
  
        /* stats for the tunnel include all the data after the IP header
           just like a norml IP-IP tunnel */
        vlib_buffer_advance (b[0], buf_adv0);
        len0 = vlib_buffer_length_in_chain (vm, b[0]);
  
        if (is_ip6)
  	{
  	  key60.remote_ip = ip60->src_address;
  	  key60.spi = esp0->spi;
  
  	  if (memcmp (&key60, &last_key6, sizeof (last_key6)) == 0)
  	    {
  	      tid0 = last_tunnel_id;
  	    }
  	  else
  	    {
  	      uword *p =
  		hash_get_mem (im->ipsec6_if_pool_index_by_key, &key60);
  	      if (p)
  		{
  		  tid0 = p[0];
  		  last_tunnel_id = tid0;
  		  clib_memcpy_fast (&last_key6, &key60, sizeof (key60));
  		}
  	      else
  		{
  		  next[0] =
  		    ipsec_ip6_if_no_tunnel (node, b[0], esp0, buf_adv0);
  		  n_no_tunnel++;
  		  goto trace00;
  		}
  	    }
  	}
        else			/* !is_ip6 */
  	{
  	  key40.remote_ip = ip40->src_address.as_u32;
  	  key40.spi = esp0->spi;
  
  	  if (key40.as_u64 == last_key4.as_u64)
  	    {
  	      tid0 = last_tunnel_id;
  	    }
  	  else
  	    {
  	      uword *p =
  		hash_get (im->ipsec4_if_pool_index_by_key, key40.as_u64);
  	      if (p)
  		{
  		  tid0 = p[0];
  		  last_tunnel_id = tid0;
  		  last_key4.as_u64 = key40.as_u64;
  		}
  	      else
  		{
  		  next[0] =
  		    ipsec_ip4_if_no_tunnel (node, b[0], esp0, ip40,
  					    buf_rewind0);
  		  n_no_tunnel++;
  		  goto trace00;
  		}
  	    }
  	}
  
        t0 = pool_elt_at_index (im->tunnel_interfaces, tid0);
        vnet_buffer (b[0])->ipsec.sad_index = t0->input_sa_index;
  
        if (PREDICT_TRUE (t0->hw_if_index != ~0))
  	{
  	  sw_if_index0 = t0->sw_if_index;
  	  vnet_buffer (b[0])->sw_if_index[VLIB_RX] = sw_if_index0;
  
  	  if (PREDICT_FALSE (!(t0->flags & VNET_HW_INTERFACE_FLAG_LINK_UP)))
  	    {
  	      vlib_increment_combined_counter
  		(drop_counter, thread_index, sw_if_index0, 1, len0);
  	      n_disabled++;
  	      b[0]->error = node->errors[IPSEC_IF_INPUT_ERROR_DISABLED];
  	      next[0] = IPSEC_INPUT_NEXT_DROP;
  	      goto trace00;
  	    }
  
  	  if (PREDICT_TRUE (sw_if_index0 == last_sw_if_index))
  	    {
  	      n_packets++;
  	      n_bytes += len0;
  	    }
  	  else
  	    {
  	      if (n_packets)
  		{
  		  vlib_increment_combined_counter
  		    (rx_counter, thread_index, last_sw_if_index,
  		     n_packets, n_bytes);
  		}
  
  	      last_sw_if_index = sw_if_index0;
  	      n_packets = 1;
  	      n_bytes = len0;
  	    }
  	}
  
      trace00:
        if (PREDICT_FALSE (is_trace))
  	{
  	  if (b[0]->flags & VLIB_BUFFER_IS_TRACED)
  	    {
  	      ipsec_if_input_trace_t *tr =
  		vlib_add_trace (vm, node, b[0], sizeof (*tr));
  	      tr->spi = clib_host_to_net_u32 (esp0->spi);
  	      tr->seq = clib_host_to_net_u32 (esp0->seq);
  	    }
  	}
  
        /* next */
        b += 1;
        next += 1;
        n_left_from -= 1;
      }
  
    if (n_packets)
      {
        vlib_increment_combined_counter (rx_counter,
  				       thread_index,
  				       last_sw_if_index, n_packets, n_bytes);
      }
  
    vlib_node_increment_counter (vm, node->node_index,
  			       IPSEC_IF_INPUT_ERROR_RX,
  			       from_frame->n_vectors - (n_disabled +
  							n_no_tunnel));
  
    vlib_buffer_enqueue_to_next (vm, node, from, nexts, from_frame->n_vectors);
  
    return from_frame->n_vectors;
  }
  
  VLIB_NODE_FN (ipsec4_if_input_node) (vlib_main_t * vm,
  				     vlib_node_runtime_t * node,
  				     vlib_frame_t * from_frame)
  {
    return ipsec_if_input_inline (vm, node, from_frame, 0 /* is_ip6 */ );
  }
  
  /* *INDENT-OFF* */
  VLIB_REGISTER_NODE (ipsec4_if_input_node) = {
    .name = "ipsec4-if-input",
    .vector_size = sizeof (u32),
    .format_trace = format_ipsec_if_input_trace,
    .type = VLIB_NODE_TYPE_INTERNAL,
    .n_errors = ARRAY_LEN(ipsec_if_input_error_strings),
    .error_strings = ipsec_if_input_error_strings,
    .sibling_of = "ipsec4-input-feature",
  };
  /* *INDENT-ON* */
  
  VLIB_NODE_FN (ipsec6_if_input_node) (vlib_main_t * vm,
  				     vlib_node_runtime_t * node,
  				     vlib_frame_t * from_frame)
  {
    return ipsec_if_input_inline (vm, node, from_frame, 1 /* is_ip6 */ );
  }
  
  /* *INDENT-OFF* */
  VLIB_REGISTER_NODE (ipsec6_if_input_node) = {
    .name = "ipsec6-if-input",
    .vector_size = sizeof (u32),
    .format_trace = format_ipsec_if_input_trace,
    .type = VLIB_NODE_TYPE_INTERNAL,
    .n_errors = ARRAY_LEN(ipsec_if_input_error_strings),
    .error_strings = ipsec_if_input_error_strings,
    .sibling_of = "ipsec6-input-feature",
  };
  /* *INDENT-ON* */
  
  /*
   * fd.io coding-style-patch-verification: ON
   *
   * Local Variables:
   * eval: (c-set-style "gnu")
   * End:
   */
  