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authorNeale Ranns <neale@graphiant.com>2022-02-24 10:30:12 +0000
committerBeno�t Ganne <bganne@cisco.com>2022-03-04 14:38:27 +0000
commitc396d2395a98f9966501316351619b19da5bc548 (patch)
treed8e6ae49162c4c992cafeaeaaf20b935d7f3c5d9 /src
parent0a3160b698baa8a65edefbec90a2c748381d1ae4 (diff)
mpls: Fix the fragmentation in mpls-output.
Type: fix the MTU needs to be adjusted to account for the label stack, since the size of fragments produced is stack+mtu. these changes are to the use of the stack variable 'mtu' most of the patch results from appeasing checkstyle. Signed-off-by: Neale Ranns <neale@graphiant.com> Change-Id: I8d0e10cf52ca4dd8ecdc224ed6c54a13e4768fdd
Diffstat (limited to 'src')
-rw-r--r--src/vnet/mpls/mpls_output.c164
1 files changed, 80 insertions, 84 deletions
diff --git a/src/vnet/mpls/mpls_output.c b/src/vnet/mpls/mpls_output.c
index a1d2d3baa88..3699163a155 100644
--- a/src/vnet/mpls/mpls_output.c
+++ b/src/vnet/mpls/mpls_output.c
@@ -411,90 +411,86 @@ mpls_frag (vlib_main_t * vm,
u32 pi0, adj_index0;
ip_frag_error_t error0 = IP_FRAG_ERROR_NONE;
i16 encap_size;
- u8 is_ip4;
-
- pi0 = to_next[0] = from[0];
- p0 = vlib_get_buffer (vm, pi0);
- from += 1;
- n_left_from -= 1;
- is_ip4 = vnet_buffer (p0)->mpls.pyld_proto == DPO_PROTO_IP4;
-
- adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
- adj0 = adj_get(adj_index0);
-
- /* the size of the MPLS stack */
- encap_size = vnet_buffer(p0)->l3_hdr_offset - p0->current_data;
-
- /* IP fragmentation */
- if (is_ip4)
- error0 = ip4_frag_do_fragment (vm, pi0,
- adj0->rewrite_header.max_l3_packet_bytes,
- encap_size, &frags);
- else
- error0 = ip6_frag_do_fragment (vm, pi0,
- adj0->rewrite_header.max_l3_packet_bytes,
- encap_size, &frags);
-
- if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED))
- {
- mpls_frag_trace_t *tr =
- vlib_add_trace (vm, node, p0, sizeof (*tr));
- tr->mtu = adj0->rewrite_header.max_l3_packet_bytes;
- tr->pkt_size = vlib_buffer_length_in_chain(vm, p0);
- }
-
- if (PREDICT_TRUE(error0 == IP_FRAG_ERROR_NONE))
- {
- /* Free original buffer chain */
- vlib_buffer_free_one (vm, pi0); /* Free original packet */
- next0 = (IP_LOOKUP_NEXT_MIDCHAIN == adj0->lookup_next_index ?
- MPLS_FRAG_NEXT_REWRITE_MIDCHAIN :
- MPLS_FRAG_NEXT_REWRITE);
- }
- else if (is_ip4 && error0 == IP_FRAG_ERROR_DONT_FRAGMENT_SET)
- {
- icmp4_error_set_vnet_buffer (
- p0, ICMP4_destination_unreachable,
- ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set,
- vnet_buffer (p0)->ip_frag.mtu);
- next0 = MPLS_FRAG_NEXT_ICMP_ERROR;
- }
- else
- {
- vlib_error_count (vm, mpls_output_node.index, error0, 1);
- vec_add1 (frags, pi0); /* Get rid of the original buffer */
- next0 = MPLS_FRAG_NEXT_DROP;
- }
-
- /* Send fragments that were added in the frame */
- u32 *frag_from, frag_left;
-
- frag_from = frags;
- frag_left = vec_len (frags);
-
- while (frag_left > 0)
- {
- while (frag_left > 0 && n_left_to_next > 0)
- {
- u32 i;
- i = to_next[0] = frag_from[0];
- frag_from += 1;
- frag_left -= 1;
- to_next += 1;
- n_left_to_next -= 1;
-
- p0 = vlib_get_buffer (vm, i);
- p0->error = error_node->errors[error0];
-
- vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
- to_next, n_left_to_next, i,
- next0);
- }
- vlib_put_next_frame (vm, node, next_index, n_left_to_next);
- vlib_get_next_frame (vm, node, next_index, to_next,
- n_left_to_next);
- }
- vec_reset_length (frags);
+ u16 mtu;
+ u8 is_ip4;
+
+ pi0 = to_next[0] = from[0];
+ p0 = vlib_get_buffer (vm, pi0);
+ from += 1;
+ n_left_from -= 1;
+ is_ip4 = vnet_buffer (p0)->mpls.pyld_proto == DPO_PROTO_IP4;
+
+ adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
+ adj0 = adj_get (adj_index0);
+ /* the size of the MPLS stack */
+ encap_size = vnet_buffer (p0)->l3_hdr_offset - p0->current_data;
+ mtu = adj0->rewrite_header.max_l3_packet_bytes - encap_size;
+
+ /* IP fragmentation */
+ if (is_ip4)
+ error0 = ip4_frag_do_fragment (vm, pi0, mtu, encap_size, &frags);
+ else
+ error0 = ip6_frag_do_fragment (vm, pi0, mtu, encap_size, &frags);
+
+ if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED))
+ {
+ mpls_frag_trace_t *tr =
+ vlib_add_trace (vm, node, p0, sizeof (*tr));
+ tr->mtu = mtu;
+ tr->pkt_size = vlib_buffer_length_in_chain (vm, p0);
+ }
+
+ if (PREDICT_TRUE (error0 == IP_FRAG_ERROR_NONE))
+ {
+ /* Free original buffer chain */
+ vlib_buffer_free_one (vm, pi0); /* Free original packet */
+ next0 = (IP_LOOKUP_NEXT_MIDCHAIN == adj0->lookup_next_index ?
+ MPLS_FRAG_NEXT_REWRITE_MIDCHAIN :
+ MPLS_FRAG_NEXT_REWRITE);
+ }
+ else if (is_ip4 && error0 == IP_FRAG_ERROR_DONT_FRAGMENT_SET)
+ {
+ icmp4_error_set_vnet_buffer (
+ p0, ICMP4_destination_unreachable,
+ ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set,
+ vnet_buffer (p0)->ip_frag.mtu);
+ next0 = MPLS_FRAG_NEXT_ICMP_ERROR;
+ }
+ else
+ {
+ vlib_error_count (vm, mpls_output_node.index, error0, 1);
+ vec_add1 (frags, pi0); /* Get rid of the original buffer */
+ next0 = MPLS_FRAG_NEXT_DROP;
+ }
+
+ /* Send fragments that were added in the frame */
+ u32 *frag_from, frag_left;
+
+ frag_from = frags;
+ frag_left = vec_len (frags);
+
+ while (frag_left > 0)
+ {
+ while (frag_left > 0 && n_left_to_next > 0)
+ {
+ u32 i;
+ i = to_next[0] = frag_from[0];
+ frag_from += 1;
+ frag_left -= 1;
+ to_next += 1;
+ n_left_to_next -= 1;
+
+ p0 = vlib_get_buffer (vm, i);
+ p0->error = error_node->errors[error0];
+
+ vlib_validate_buffer_enqueue_x1 (
+ vm, node, next_index, to_next, n_left_to_next, i, next0);
+ }
+ vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+ vlib_get_next_frame (vm, node, next_index, to_next,
+ n_left_to_next);
+ }
+ vec_reset_length (frags);
}
vlib_put_next_frame (vm, node, next_index, n_left_to_next);
}
> 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 
/*
 * ipsec_tun.h : IPSEC tunnel protection
 *
 * 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/ipsec/ipsec_tun.h>
#include <vnet/ipsec/ipsec_itf.h>
#include <vnet/ipsec/esp.h>
#include <vnet/udp/udp_local.h>
#include <vnet/adj/adj_delegate.h>
#include <vnet/adj/adj_midchain.h>
#include <vnet/teib/teib.h>

/* instantiate the bihash functions */
#include <vppinfra/bihash_8_16.h>
#include <vppinfra/bihash_template.c>
#include <vppinfra/bihash_24_16.h>
#include <vppinfra/bihash_template.c>

#define IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS (64 * 1024)
#define IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE 512 << 20

/**
 * The logger
 */
vlib_log_class_t ipsec_tun_protect_logger;

/**
 * Pool of tunnel protection objects
 */
ipsec_tun_protect_t *ipsec_tun_protect_pool;

/**
 * Adj delegate registered type
 */
static adj_delegate_type_t ipsec_tun_adj_delegate_type;

/**
 * Adj index to TX SA mapping
 */
index_t *ipsec_tun_protect_sa_by_adj_index;

const ip_address_t IP_ADDR_ALL_0 = IP_ADDRESS_V4_ALL_0S;

/**
 * The DB of all added per-nh tunnel protectiond
 */
typedef struct ipsec_tun_protect_itf_db_t_
{
  /** A hash table key'd on IP (4 or 6) address */
  uword *id_hash;
  /** If the interface is P2P then there is only one protect
   * object associated with the auto-adj for each NH proto */
  index_t id_itp;
} ipsec_tun_protect_itf_db_t;

typedef struct ipsec_tun_protect_db_t_
{
  /** Per-interface vector */
  ipsec_tun_protect_itf_db_t *id_itf;
} ipsec_tun_protect_db_t;

static ipsec_tun_protect_db_t itp_db;

const static ipsec_tun_protect_itf_db_t IPSEC_TUN_PROTECT_DEFAULT_DB_ENTRY = {
  .id_itp = INDEX_INVALID,
};

#define ITP_DBG(_itp, _fmt, _args...)                   \
{   		          				\
  vlib_log_debug(ipsec_tun_protect_logger,              \
                 "[%U]: " _fmt,                         \
                 format_ipsec_tun_protect,              \
                 _itp, ##_args);                        \
}

#define ITP_DBG2(_fmt, _args...)                        \
{   		          				\
  vlib_log_debug(ipsec_tun_protect_logger,              \
                 _fmt, ##_args);                        \
}

static u32 ipsec_tun_node_regs[N_AF];

void
ipsec_tun_register_nodes (ip_address_family_t af)
{
  if (0 == ipsec_tun_node_regs[af]++)
    {
      if (AF_IP4 == af)
	{
	  ipsec_register_udp_port (UDP_DST_PORT_ipsec);
	  ip4_register_protocol (IP_PROTOCOL_IPSEC_ESP,
				 ipsec4_tun_input_node.index);
	}
      else
	ip6_register_protocol (IP_PROTOCOL_IPSEC_ESP,
			       ipsec6_tun_input_node.index);
    }
}

void
ipsec_tun_unregister_nodes (ip_address_family_t af)
{
  ASSERT (0 != ipsec_tun_node_regs[af]);
  if (0 == --ipsec_tun_node_regs[af])
    {
      if (AF_IP4 == af)
	{
	  ipsec_unregister_udp_port (UDP_DST_PORT_ipsec);
	  ip4_unregister_protocol (IP_PROTOCOL_IPSEC_ESP);
	}
      else
	ip6_unregister_protocol (IP_PROTOCOL_IPSEC_ESP);
    }
}

static inline const ipsec_tun_protect_t *
ipsec_tun_protect_from_const_base (const adj_delegate_t * ad)
{
  if (ad == NULL)
    return (NULL);
  return (pool_elt_at_index (ipsec_tun_protect_pool, ad->ad_index));
}

static u32
ipsec_tun_protect_get_adj_next (vnet_link_t linkt,
				const ipsec_tun_protect_t * itp)
{
  ipsec_main_t *im;
  ipsec_sa_t *sa;
  bool is_ip4;
  u32 next;


  if (itp->itp_flags & IPSEC_PROTECT_ITF)
    is_ip4 = linkt == VNET_LINK_IP4;
  else
    is_ip4 = ip46_address_is_ip4 (&itp->itp_tun.src);

  sa = ipsec_sa_get (itp->itp_out_sa);
  im = &ipsec_main;

  if ((sa->crypto_alg == IPSEC_CRYPTO_ALG_NONE &&
       sa->integ_alg == IPSEC_INTEG_ALG_NONE) &&
      !(itp->itp_flags & IPSEC_PROTECT_ITF))
    next = (is_ip4 ?
	    im->esp4_no_crypto_tun_node_index :
	    im->esp6_no_crypto_tun_node_index);
  else if (itp->itp_flags & IPSEC_PROTECT_L2)
    next = (is_ip4 ?
	    im->esp4_encrypt_l2_tun_node_index :
	    im->esp6_encrypt_l2_tun_node_index);
  else
    next = (is_ip4 ?
	    im->esp4_encrypt_tun_node_index :
	    im->esp6_encrypt_tun_node_index);

  return (next);
}

static void
ipsec_tun_protect_add_adj (adj_index_t ai, const ipsec_tun_protect_t * itp)
{
  vec_validate_init_empty (ipsec_tun_protect_sa_by_adj_index, ai,
			   INDEX_INVALID);

  if (NULL == itp)
    {
      ipsec_tun_protect_sa_by_adj_index[ai] = INDEX_INVALID;
      adj_nbr_midchain_reset_next_node (ai);
    }
  else
    {
      ipsec_tun_protect_sa_by_adj_index[ai] = itp->itp_out_sa;
      adj_nbr_midchain_update_next_node
	(ai, ipsec_tun_protect_get_adj_next (adj_get_link_type (ai), itp));
    }
}

static index_t
ipsec_tun_protect_find (u32 sw_if_index, const ip_address_t * nh)
{
  ipsec_tun_protect_itf_db_t *idi;
  uword *p;

  if (vec_len (itp_db.id_itf) <= sw_if_index)
    return INDEX_INVALID;

  if (vnet_sw_interface_is_p2p (vnet_get_main (), sw_if_index))
    return (itp_db.id_itf[sw_if_index].id_itp);

  idi = &itp_db.id_itf[sw_if_index];
  p = hash_get_mem (idi->id_hash, nh);

  if (NULL == p)
    {
      return INDEX_INVALID;
    }
  return (p[0]);
}

static void
ipsec_tun_protect_rx_db_add (ipsec_main_t * im,
			     const ipsec_tun_protect_t * itp)
{
  const ipsec_sa_t *sa;
  u32 sai;

  if (ip46_address_is_zero (&itp->itp_crypto.dst))
    return;

  /* *INDENT-OFF* */
  FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
  ({
      sa = ipsec_sa_get (sai);

      ipsec_tun_lkup_result_t res = {
        .tun_index = itp - ipsec_tun_protect_pool,
        .sa_index = sai,
        .flags = itp->itp_flags,
        .sw_if_index = itp->itp_sw_if_index,
      };

      /*
       * The key is formed from the tunnel's destination
       * as the packet lookup is done from the packet's source
       */
      if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
        {
          ipsec4_tunnel_kv_t key = {
            .value = res,
          };
          clib_bihash_kv_8_16_t *bkey = (clib_bihash_kv_8_16_t*)&key;

          ipsec4_tunnel_mk_key(&key, &itp->itp_crypto.dst.ip4,
                               clib_host_to_net_u32 (sa->spi));

          if (!im->tun4_protect_by_key.nbuckets)
              clib_bihash_init_8_16 (&im->tun4_protect_by_key,
			"IPSec IPv4 tunnels",
			IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS,
			IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE);

          clib_bihash_add_del_8_16 (&im->tun4_protect_by_key, bkey, 1);
          ipsec_tun_register_nodes(AF_IP4);
        }
      else
        {
          ipsec6_tunnel_kv_t key = {
            .key = {
              .remote_ip = itp->itp_crypto.dst.ip6,
              .spi = clib_host_to_net_u32 (sa->spi),
            },
            .value = res,
          };
          clib_bihash_kv_24_16_t *bkey = (clib_bihash_kv_24_16_t*)&key;

          if (!im->tun4_protect_by_key.nbuckets)
            clib_bihash_init_24_16 (&im->tun6_protect_by_key,
                                   "IPSec IPv6 tunnels",
                                   IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS,
                                   IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE);
          clib_bihash_add_del_24_16 (&im->tun6_protect_by_key, bkey, 1);
          ipsec_tun_register_nodes(AF_IP6);
        }
  }))
  /* *INDENT-ON* */
}

static adj_walk_rc_t
ipsec_tun_protect_adj_add (adj_index_t ai, void *arg)
{
  ipsec_tun_protect_t *itp = arg;
  adj_delegate_add (adj_get (ai), ipsec_tun_adj_delegate_type,
		    itp - ipsec_tun_protect_pool);
  ipsec_tun_protect_add_adj (ai, itp);

  if (itp->itp_flags & IPSEC_PROTECT_ITF)
    ipsec_itf_adj_stack (ai, itp->itp_out_sa);

  return (ADJ_WALK_RC_CONTINUE);
}

static void
ipsec_tun_protect_tx_db_add (ipsec_tun_protect_t * itp)
{
  /*
   * add the delegate to the adj
   */
  ipsec_tun_protect_itf_db_t *idi;
  fib_protocol_t nh_proto;
  ip46_address_t nh;

  vec_validate_init_empty (itp_db.id_itf,
			   itp->itp_sw_if_index,
			   IPSEC_TUN_PROTECT_DEFAULT_DB_ENTRY);

  idi = &itp_db.id_itf[itp->itp_sw_if_index];

  if (vnet_sw_interface_is_p2p (vnet_get_main (), itp->itp_sw_if_index))
    {
      if (INDEX_INVALID == idi->id_itp)
	{
	  // ipsec_tun_protect_feature_set (itp, 1);
	}
      idi->id_itp = itp - ipsec_tun_protect_pool;

      FOR_EACH_FIB_IP_PROTOCOL (nh_proto)
	adj_nbr_walk (itp->itp_sw_if_index,
		      nh_proto, ipsec_tun_protect_adj_add, itp);
    }
  else
    {
      if (NULL == idi->id_hash)
	{
	  idi->id_hash =
	    hash_create_mem (0, sizeof (ip_address_t), sizeof (uword));
	  /*
	   * enable the encrypt feature for egress if this is the first addition
	   * on this interface
	   */
	  // ipsec_tun_protect_feature_set (itp, 1);
	}

      hash_set_mem (idi->id_hash, itp->itp_key, itp - ipsec_tun_protect_pool);

      /*
       * walk all the adjs with the same nh on this interface
       * to associate them with this protection
       */
      nh_proto = ip_address_to_46 (itp->itp_key, &nh);

      adj_nbr_walk_nh (itp->itp_sw_if_index,
		       nh_proto, &nh, ipsec_tun_protect_adj_add, itp);

      ipsec_tun_register_nodes (FIB_PROTOCOL_IP6 == nh_proto ?
				AF_IP6 : AF_IP4);
    }
}

static void
ipsec_tun_protect_rx_db_remove (ipsec_main_t * im,
				const ipsec_tun_protect_t * itp)
{
  const ipsec_sa_t *sa;

  /* *INDENT-OFF* */
  FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
  ({
    if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
      {
          ipsec4_tunnel_kv_t key;
          clib_bihash_kv_8_16_t res, *bkey = (clib_bihash_kv_8_16_t*)&key;

          ipsec4_tunnel_mk_key(&key, &itp->itp_crypto.dst.ip4,
                               clib_host_to_net_u32 (sa->spi));

          if (!clib_bihash_search_8_16 (&im->tun4_protect_by_key, bkey, &res))
            {
              clib_bihash_add_del_8_16 (&im->tun4_protect_by_key, bkey, 0);
              ipsec_tun_unregister_nodes(AF_IP4);
            }
      }
    else
      {
        ipsec6_tunnel_kv_t key = {
          .key = {
            .remote_ip = itp->itp_crypto.dst.ip6,
            .spi = clib_host_to_net_u32 (sa->spi),
          },
        };
        clib_bihash_kv_24_16_t res, *bkey = (clib_bihash_kv_24_16_t*)&key;

        if (!clib_bihash_search_24_16 (&im->tun6_protect_by_key, bkey, &res))
          {
            clib_bihash_add_del_24_16 (&im->tun6_protect_by_key, bkey, 0);
            ipsec_tun_unregister_nodes(AF_IP6);
          }
      }
  }));
  /* *INDENT-ON* */
}

static adj_walk_rc_t
ipsec_tun_protect_adj_remove (adj_index_t ai, void *arg)
{
  ipsec_tun_protect_t *itp = arg;

  adj_delegate_remove (ai, ipsec_tun_adj_delegate_type);
  ipsec_tun_protect_add_adj (ai, NULL);

  if (itp->itp_flags & IPSEC_PROTECT_ITF)
    ipsec_itf_adj_unstack (ai);

  return (ADJ_WALK_RC_CONTINUE);
}

static void
ipsec_tun_protect_tx_db_remove (ipsec_tun_protect_t * itp)
{
  ipsec_tun_protect_itf_db_t *idi;
  fib_protocol_t nh_proto;
  ip46_address_t nh;

  nh_proto = ip_address_to_46 (itp->itp_key, &nh);
  idi = &itp_db.id_itf[itp->itp_sw_if_index];

  if (vnet_sw_interface_is_p2p (vnet_get_main (), itp->itp_sw_if_index))
    {
      // ipsec_tun_protect_feature_set (itp, 0);
      idi->id_itp = INDEX_INVALID;

      FOR_EACH_FIB_IP_PROTOCOL (nh_proto)
	adj_nbr_walk (itp->itp_sw_if_index,
		      nh_proto, ipsec_tun_protect_adj_remove, itp);
    }
  else
    {
      adj_nbr_walk_nh (itp->itp_sw_if_index,
		       nh_proto, &nh, ipsec_tun_protect_adj_remove, itp);

      hash_unset_mem (idi->id_hash, itp->itp_key);

      if (0 == hash_elts (idi->id_hash))
	{
	  // ipsec_tun_protect_feature_set (itp, 0);
	  hash_free (idi->id_hash);
	  idi->id_hash = NULL;
	}
      ipsec_tun_unregister_nodes (FIB_PROTOCOL_IP6 == nh_proto ?
				  AF_IP6 : AF_IP4);
    }
}

static void
ipsec_tun_protect_set_crypto_addr (ipsec_tun_protect_t * itp)
{
  ipsec_sa_t *sa;

  /* *INDENT-OFF* */
  FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
  ({
    if (ipsec_sa_is_set_IS_TUNNEL (sa))
      {
        itp->itp_crypto.src = sa->tunnel_dst_addr;
        itp->itp_crypto.dst = sa->tunnel_src_addr;
        if (!(itp->itp_flags & IPSEC_PROTECT_ITF))
          {
            ipsec_sa_set_IS_PROTECT (sa);
            itp->itp_flags |= IPSEC_PROTECT_ENCAPED;
          }
      }
    else
      {
        itp->itp_crypto.src = itp->itp_tun.src;
        itp->itp_crypto.dst = itp->itp_tun.dst;
        itp->itp_flags &= ~IPSEC_PROTECT_ENCAPED;
      }
  }));
  /* *INDENT-ON* */
}

static void
ipsec_tun_protect_config (ipsec_main_t * im,
			  ipsec_tun_protect_t * itp, u32 sa_out, u32 * sas_in)
{
  index_t sai;
  u32 ii;

  itp->itp_n_sa_in = vec_len (sas_in);
  for (ii = 0; ii < itp->itp_n_sa_in; ii++)
    itp->itp_in_sas[ii] = sas_in[ii];
  itp->itp_out_sa = sa_out;

  ipsec_sa_lock (itp->itp_out_sa);

  /* *INDENT-OFF* */
  FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
  ({
    ipsec_sa_lock(sai);
  }));
  ipsec_tun_protect_set_crypto_addr(itp);
  /* *INDENT-ON* */

  /*
   * add to the DB against each SA
   */
  ipsec_tun_protect_rx_db_add (im, itp);
  ipsec_tun_protect_tx_db_add (itp);

  ITP_DBG (itp, "configured");
}

static void
ipsec_tun_protect_unconfig (ipsec_main_t * im, ipsec_tun_protect_t * itp)
{
  ipsec_sa_t *sa;
  index_t sai;

  /* *INDENT-OFF* */
  FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
  ({
    ipsec_sa_unset_IS_PROTECT (sa);
  }));

  ipsec_tun_protect_rx_db_remove (im, itp);
  ipsec_tun_protect_tx_db_remove (itp);

  ipsec_sa_unlock(itp->itp_out_sa);

  FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
  ({
    ipsec_sa_unlock(sai);
  }));
  /* *INDENT-ON* */
  ITP_DBG (itp, "unconfigured");
}

int
ipsec_tun_protect_update_one (u32 sw_if_index,
			      const ip_address_t * nh, u32 sa_out, u32 sa_in)
{
  u32 *sas_in = NULL;
  int rv;

  vec_add1 (sas_in, sa_in);
  rv = ipsec_tun_protect_update (sw_if_index, nh, sa_out, sas_in);

  return (rv);
}

int
ipsec_tun_protect_update_out (u32 sw_if_index,
			      const ip_address_t * nh, u32 sa_out)
{
  u32 itpi, *sas_in, sai, *saip;
  ipsec_tun_protect_t *itp;
  ipsec_main_t *im;
  int rv;

  sas_in = NULL;
  rv = 0;
  im = &ipsec_main;

  itpi = ipsec_tun_protect_find (sw_if_index, nh);

  if (INDEX_INVALID == itpi)
    {
      return (VNET_API_ERROR_INVALID_INTERFACE);
    }

  itp = pool_elt_at_index (ipsec_tun_protect_pool, itpi);

  /* *INDENT-OFF* */
  FOR_EACH_IPSEC_PROTECT_INPUT_SAI (itp, sai,
  ({
    ipsec_sa_lock (sai);
    vec_add1 (sas_in, sai);
  }));
  /* *INDENT-ON* */

  sa_out = ipsec_sa_find_and_lock (sa_out);

  if (~0 == sa_out)
    {
      rv = VNET_API_ERROR_INVALID_VALUE;
      goto out;
    }

  ipsec_tun_protect_unconfig (im, itp);
  ipsec_tun_protect_config (im, itp, sa_out, sas_in);

  ipsec_sa_unlock (sa_out);
  vec_foreach (saip, sas_in) ipsec_sa_unlock (*saip);

out:
  vec_free (sas_in);
  return (rv);
}

int
ipsec_tun_protect_update_in (u32 sw_if_index,
			     const ip_address_t * nh, u32 sa_in)
{
  u32 itpi, *sas_in, sa_out;
  ipsec_tun_protect_t *itp;
  ipsec_main_t *im;
  int rv;

  sas_in = NULL;
  rv = 0;
  im = &ipsec_main;
  itpi = ipsec_tun_protect_find (sw_if_index, nh);

  if (INDEX_INVALID == itpi)
    {
      return (VNET_API_ERROR_INVALID_INTERFACE);
    }

  sa_in = ipsec_sa_find_and_lock (sa_in);

  if (~0 == sa_in)
    {
      rv = VNET_API_ERROR_INVALID_VALUE;
      goto out;
    }
  vec_add1 (sas_in, sa_in);

  itp = pool_elt_at_index (ipsec_tun_protect_pool, itpi);
  sa_out = itp->itp_out_sa;

  ipsec_sa_lock (sa_out);

  ipsec_tun_protect_unconfig (im, itp);
  ipsec_tun_protect_config (im, itp, sa_out, sas_in);

  ipsec_sa_unlock (sa_out);
  ipsec_sa_unlock (sa_in);
out:
  vec_free (sas_in);
  return (rv);
}

static void
ipsec_tun_protect_update_from_teib (ipsec_tun_protect_t * itp,
				    const teib_entry_t * ne)
{
  if (NULL != ne)
    {
      const fib_prefix_t *pfx;

      pfx = teib_entry_get_nh (ne);

      ip46_address_copy (&itp->itp_tun.dst, &pfx->fp_addr);
    }
  else
    ip46_address_reset (&itp->itp_tun.dst);
}

int
ipsec_tun_protect_update (u32 sw_if_index,
			  const ip_address_t * nh, u32 sa_out, u32 * sas_in)
{
  ipsec_tun_protect_t *itp;
  u32 itpi, ii, *saip;
  ipsec_main_t *im;
  int rv;

  ITP_DBG2 ("update: %U/%U",
	    format_vnet_sw_if_index_name, vnet_get_main (), sw_if_index,
	    format_ip_address, nh);

  if (vec_len (sas_in) > ITP_MAX_N_SA_IN)
    {
      rv = VNET_API_ERROR_LIMIT_EXCEEDED;
      goto out;
    }

  rv = 0;
  im = &ipsec_main;
  if (NULL == nh)
    nh = &IP_ADDR_ALL_0;
  itpi = ipsec_tun_protect_find (sw_if_index, nh);

  vec_foreach_index (ii, sas_in)
  {
    sas_in[ii] = ipsec_sa_find_and_lock (sas_in[ii]);
    if (~0 == sas_in[ii])
      {
	rv = VNET_API_ERROR_INVALID_VALUE;
	goto out;
      }
  }

  sa_out = ipsec_sa_find_and_lock (sa_out);

  if (~0 == sa_out)
    {
      rv = VNET_API_ERROR_INVALID_VALUE;
      goto out;
    }

  if (INDEX_INVALID == itpi)
    {
      vnet_device_class_t *dev_class;
      vnet_hw_interface_t *hi;
      vnet_main_t *vnm;
      u8 is_l2;

      vnm = vnet_get_main ();
      hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
      dev_class = vnet_get_device_class (vnm, hi->dev_class_index);

      if (NULL == dev_class->ip_tun_desc)
	{
	  rv = VNET_API_ERROR_INVALID_SW_IF_INDEX;
	  goto out;
	}

      pool_get_zero (ipsec_tun_protect_pool, itp);

      itp->itp_sw_if_index = sw_if_index;
      itp->itp_ai = ADJ_INDEX_INVALID;

      itp->itp_n_sa_in = vec_len (sas_in);
      for (ii = 0; ii < itp->itp_n_sa_in; ii++)
	itp->itp_in_sas[ii] = sas_in[ii];
      itp->itp_out_sa = sa_out;

      itp->itp_key = clib_mem_alloc (sizeof (*itp->itp_key));
      ip_address_copy (itp->itp_key, nh);

      rv = dev_class->ip_tun_desc (sw_if_index,
				   &itp->itp_tun.src,
				   &itp->itp_tun.dst, &is_l2);

      if (rv)
	goto out;

      if (ip46_address_is_zero (&itp->itp_tun.src))
	{
	  /*
	   * must be one of those pesky ipsec interfaces that has no encap.
	   * the encap then MUST come from the tunnel mode SA.
	   */
	  ipsec_sa_t *sa;

	  sa = ipsec_sa_get (itp->itp_out_sa);

	  if (!ipsec_sa_is_set_IS_TUNNEL (sa))
	    {
	      rv = VNET_API_ERROR_INVALID_DST_ADDRESS;
	      goto out;
	    }

	  itp->itp_flags |= IPSEC_PROTECT_ITF;
	}
      else if (ip46_address_is_zero (&itp->itp_tun.dst))
	{
	  /* tunnel has no destination address, presumably because it's p2mp
	     in which case we use the nh that this is protection for */
	  ipsec_tun_protect_update_from_teib
	    (itp, teib_entry_find (sw_if_index, nh));
	}

      if (is_l2)
	itp->itp_flags |= IPSEC_PROTECT_L2;

      /*
       * add to the tunnel DB for ingress
       *  - if the SA is in trasnport mode, then the packates will arrive
       *    with the IP src,dst of the protected tunnel, in which case we can
       *    simply strip the IP header and hand the payload to the protocol
       *    appropriate input handler
       *  - if the SA is in tunnel mode then there are two IP headers present
       *    one for the crytpo tunnel endpoints (described in the SA) and one
       *    for the tunnel endpoints. The outer IP headers in the srriving
       *    packets will have the crypto endpoints. So the DB needs to contain
       *    the crpto endpoint. Once the crypto header is stripped, revealing,
       *    the tunnel-IP we have 2 choices:
       *     1) do a tunnel lookup based on the revealed header
       *     2) skip the tunnel lookup and assume that the packet matches the
       *        one that is protected here.
       *    If we did 1) then we would allow our peer to use the SA for tunnel
       *    X to inject traffic onto tunnel Y, this is not good. If we do 2)
       *    then we don't verify that the peer is indeed using SA for tunnel
       *    X and addressing tunnel X. So we take a compromise, once the SA
       *    matches to tunnel X we veriy that the inner IP matches the value
       *    of the tunnel we are protecting, else it's dropped.
       */
      ipsec_tun_protect_config (im, itp, sa_out, sas_in);
    }
  else
    {
      /* updating SAs only */
      itp = pool_elt_at_index (ipsec_tun_protect_pool, itpi);

      ipsec_tun_protect_unconfig (im, itp);
      ipsec_tun_protect_config (im, itp, sa_out, sas_in);
    }

  ipsec_sa_unlock (sa_out);
  vec_foreach (saip, sas_in) ipsec_sa_unlock (*saip);
  vec_free (sas_in);

out:
  return (rv);
}

int
ipsec_tun_protect_del (u32 sw_if_index, const ip_address_t * nh)
{
  ipsec_tun_protect_t *itp;
  ipsec_main_t *im;
  index_t itpi;

  ITP_DBG2 ("delete: %U/%U",
	    format_vnet_sw_if_index_name, vnet_get_main (), sw_if_index,
	    format_ip_address, nh);

  im = &ipsec_main;
  if (NULL == nh)
    nh = &IP_ADDR_ALL_0;

  itpi = ipsec_tun_protect_find (sw_if_index, nh);

  if (INDEX_INVALID == itpi)
    return (VNET_API_ERROR_NO_SUCH_ENTRY);

  itp = ipsec_tun_protect_get (itpi);
  ipsec_tun_protect_unconfig (im, itp);

  if (ADJ_INDEX_INVALID != itp->itp_ai)
    adj_unlock (itp->itp_ai);

  clib_mem_free (itp->itp_key);
  pool_put (ipsec_tun_protect_pool, itp);

  return (0);
}

void
ipsec_tun_protect_walk (ipsec_tun_protect_walk_cb_t fn, void *ctx)
{
  index_t itpi;

  /* *INDENT-OFF* */
  pool_foreach_index(itpi, ipsec_tun_protect_pool,
  ({
    fn (itpi, ctx);
  }));
  /* *INDENT-ON* */
}

void
ipsec_tun_protect_walk_itf (u32 sw_if_index,
			    ipsec_tun_protect_walk_cb_t fn, void *ctx)
{
  ipsec_tun_protect_itf_db_t *idi;
  ip_address_t *key;
  index_t itpi;

  if (vec_len (itp_db.id_itf) <= sw_if_index)
    return;

  idi = &itp_db.id_itf[sw_if_index];

  /* *INDENT-OFF* */
  hash_foreach(key, itpi, idi->id_hash,
  ({
    fn (itpi, ctx);
  }));
  /* *INDENT-ON* */
  if (INDEX_INVALID != idi->id_itp)
    fn (idi->id_itp, ctx);
}

static void
ipsec_tun_protect_adj_delegate_adj_deleted (adj_delegate_t * ad)
{
  /* remove our delegate */
  ipsec_tun_protect_add_adj (ad->ad_adj_index, NULL);
  adj_delegate_remove (ad->ad_adj_index, ipsec_tun_adj_delegate_type);
}

static void
ipsec_tun_protect_adj_delegate_adj_modified (adj_delegate_t * ad)
{
  ipsec_tun_protect_add_adj (ad->ad_adj_index,
			     ipsec_tun_protect_get (ad->ad_index));
}

static void
ipsec_tun_protect_adj_delegate_adj_created (adj_index_t ai)
{
  /* add our delegate if there is protection for this neighbour */
  ip_address_t ip = IP_ADDRESS_V4_ALL_0S;
  ip_adjacency_t *adj;
  index_t itpi;

  if (!adj_is_midchain (ai))
    return;

  adj = adj_get (ai);

  ip_address_from_46 (&adj->sub_type.midchain.next_hop,
		      adj->ia_nh_proto, &ip);

  itpi = ipsec_tun_protect_find (adj->rewrite_header.sw_if_index, &ip);

  if (INDEX_INVALID != itpi)
    ipsec_tun_protect_adj_add (ai, ipsec_tun_protect_get (itpi));
}

static u8 *
ipsec_tun_protect_adj_delegate_format (const adj_delegate_t * aed, u8 * s)
{
  const ipsec_tun_protect_t *itp;

  itp = ipsec_tun_protect_from_const_base (aed);
  s = format (s, "ipsec-tun-protect:\n%U", format_ipsec_tun_protect, itp);

  return (s);
}

static void
ipsec_tun_teib_entry_added (const teib_entry_t * ne)
{
  ipsec_tun_protect_t *itp;
  index_t itpi;

  itpi = ipsec_tun_protect_find (teib_entry_get_sw_if_index (ne),
				 teib_entry_get_peer (ne));

  if (INDEX_INVALID == itpi)
    return;

  itp = ipsec_tun_protect_get (itpi);
  ipsec_tun_protect_rx_db_remove (&ipsec_main, itp);
  ipsec_tun_protect_update_from_teib (itp, ne);
  ipsec_tun_protect_set_crypto_addr (itp);
  ipsec_tun_protect_rx_db_add (&ipsec_main, itp);

  ITP_DBG (itp, "teib-added");
}

static void
ipsec_tun_teib_entry_deleted (const teib_entry_t * ne)
{
  ipsec_tun_protect_t *itp;
  index_t itpi;

  itpi = ipsec_tun_protect_find (teib_entry_get_sw_if_index (ne),
				 teib_entry_get_peer (ne));

  if (INDEX_INVALID == itpi)
    return;

  itp = ipsec_tun_protect_get (itpi);
  ipsec_tun_protect_rx_db_remove (&ipsec_main, itp);
  ipsec_tun_protect_update_from_teib (itp, NULL);
  ipsec_tun_protect_set_crypto_addr (itp);

  ITP_DBG (itp, "teib-removed");
}

/**
 * VFT registered with the adjacency delegate
 */
const static adj_delegate_vft_t ipsec_tun_adj_delegate_vft = {
  .adv_adj_deleted = ipsec_tun_protect_adj_delegate_adj_deleted,
  .adv_adj_created = ipsec_tun_protect_adj_delegate_adj_created,
  .adv_adj_modified = ipsec_tun_protect_adj_delegate_adj_modified,
  .adv_format = ipsec_tun_protect_adj_delegate_format,
};

const static teib_vft_t ipsec_tun_teib_vft = {
  .nv_added = ipsec_tun_teib_entry_added,
  .nv_deleted = ipsec_tun_teib_entry_deleted,
};

void
ipsec_tun_table_init (ip_address_family_t af, uword table_size, u32 n_buckets)
{
  ipsec_main_t *im;

  im = &ipsec_main;

  if (AF_IP4 == af)
    clib_bihash_init_8_16 (&im->tun4_protect_by_key,
			   "IPSec IPv4 tunnels", n_buckets, table_size);
  else
    clib_bihash_init_24_16 (&im->tun6_protect_by_key,
			    "IPSec IPv6 tunnels", n_buckets, table_size);
}

clib_error_t *
ipsec_tunnel_protect_init (vlib_main_t * vm)
{
  ipsec_main_t *im;

  im = &ipsec_main;
  clib_bihash_init_24_16 (&im->tun6_protect_by_key,
			  "IPSec IPv6 tunnels",
			  IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS,
			  IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE);
  clib_bihash_init_8_16 (&im->tun4_protect_by_key,
			 "IPSec IPv4 tunnels",
			 IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS,
			 IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE);

  /* set up feature nodes to drop outbound packets with no crypto alg set */
  im->esp4_no_crypto_tun_node_index =
    vlib_get_node_by_name (vm, (u8 *) "esp4-no-crypto")->index;
  im->esp6_no_crypto_tun_node_index =
    vlib_get_node_by_name (vm, (u8 *) "esp6-no-crypto")->index;
  im->esp6_encrypt_l2_tun_node_index =
    vlib_get_node_by_name (vm, (u8 *) "esp6-encrypt-tun")->index;
  im->esp4_encrypt_l2_tun_node_index =
    vlib_get_node_by_name (vm, (u8 *) "esp4-encrypt-tun")->index;

  ipsec_tun_adj_delegate_type =
    adj_delegate_register_new_type (&ipsec_tun_adj_delegate_vft);

  ipsec_tun_protect_logger = vlib_log_register_class ("ipsec", "tun");

  teib_register (&ipsec_tun_teib_vft);

  return 0;
}

VLIB_INIT_FUNCTION (ipsec_tunnel_protect_init);

static clib_error_t *
ipsec_config (vlib_main_t * vm, unformat_input_t * input)
{
  unformat_input_t sub_input;

  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (input, "ip4 %U", unformat_vlib_cli_sub_input, &sub_input))
	{
	  uword table_size = ~0;
	  u32 n_buckets = ~0;

	  while (unformat_check_input (&sub_input) != UNFORMAT_END_OF_INPUT)
	    {
	      if (unformat (&sub_input, "num-buckets %u", &n_buckets))
		;
	      else
		return clib_error_return (0, "unknown input `%U'",
					  format_unformat_error, &sub_input);
	    }

	  ipsec_tun_table_init (AF_IP4, table_size, n_buckets);
	}
      else if (unformat (input, "ip6 %U", unformat_vlib_cli_sub_input,
			 &sub_input))
	{
	  uword table_size = ~0;
	  u32 n_buckets = ~0;

	  while (unformat_check_input (&sub_input) != UNFORMAT_END_OF_INPUT)
	    {
	      if (unformat (&sub_input, "num-buckets %u", &n_buckets))
		;
	      else
		return clib_error_return (0, "unknown input `%U'",
					  format_unformat_error, &sub_input);
	    }

	  ipsec_tun_table_init (AF_IP6, table_size, n_buckets);
	}
      else
	return clib_error_return (0, "unknown input `%U'",
				  format_unformat_error, input);
    }

  return 0;
}

VLIB_CONFIG_FUNCTION (ipsec_config, "ipsec");

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