ip: reassembly: handle atomic fragments correctly

[vpp.git] / src / vnet / ip / reass / ip6_full_reass.c

diff --git a/src/vnet/ip/reass/ip6_full_reass.c b/src/vnet/ip/reass/ip6_full_reass.c
index 901da99..fc7fa18 100644 (file)
--- a/src/vnet/ip/reass/ip6_full_reass.c
+++ b/src/vnet/ip/reass/ip6_full_reass.c
@@ -498,11 +498,11 @@ ip6_full_reass_on_timeout (vlib_main_t * vm, vlib_node_runtime_t * node,
 }
 
 always_inline ip6_full_reass_t *
-ip6_full_reass_find_or_create (vlib_main_t * vm, vlib_node_runtime_t * node,
-                              ip6_full_reass_main_t * rm,
-                              ip6_full_reass_per_thread_t * rt,
-                              ip6_full_reass_kv_t * kv, u32 * icmp_bi,
-                              u8 * do_handoff)
+ip6_full_reass_find_or_create (vlib_main_t *vm, vlib_node_runtime_t *node,
+                              ip6_full_reass_main_t *rm,
+                              ip6_full_reass_per_thread_t *rt,
+                              ip6_full_reass_kv_t *kv, u32 *icmp_bi,
+                              u8 *do_handoff, int skip_bihash)
 {
   ip6_full_reass_t *reass;
   f64 now;
@@ -512,7 +512,7 @@ again:
   reass = NULL;
   now = vlib_time_now (vm);
 
-  if (!clib_bihash_search_48_8 (&rm->hash, &kv->kv, &kv->kv))
+  if (!skip_bihash && !clib_bihash_search_48_8 (&rm->hash, &kv->kv, &kv->kv))
     {
       if (vm->thread_index != kv->v.memory_owner_thread_index)
        {
@@ -558,24 +558,37 @@ again:
       ++rt->reass_n;
     }
 
-  reass->key.as_u64[0] = kv->kv.key[0];
-  reass->key.as_u64[1] = kv->kv.key[1];
-  reass->key.as_u64[2] = kv->kv.key[2];
-  reass->key.as_u64[3] = kv->kv.key[3];
-  reass->key.as_u64[4] = kv->kv.key[4];
-  reass->key.as_u64[5] = kv->kv.key[5];
   kv->v.reass_index = (reass - rt->pool);
   kv->v.memory_owner_thread_index = vm->thread_index;
   reass->last_heard = now;
 
-  int rv = clib_bihash_add_del_48_8 (&rm->hash, &kv->kv, 2);
-  if (rv)
+  if (!skip_bihash)
     {
-      ip6_full_reass_free (rm, rt, reass);
-      reass = NULL;
-      // if other worker created a context already work with the other copy
-      if (-2 == rv)
-       goto again;
+      reass->key.as_u64[0] = kv->kv.key[0];
+      reass->key.as_u64[1] = kv->kv.key[1];
+      reass->key.as_u64[2] = kv->kv.key[2];
+      reass->key.as_u64[3] = kv->kv.key[3];
+      reass->key.as_u64[4] = kv->kv.key[4];
+      reass->key.as_u64[5] = kv->kv.key[5];
+
+      int rv = clib_bihash_add_del_48_8 (&rm->hash, &kv->kv, 2);
+      if (rv)
+       {
+         ip6_full_reass_free (rm, rt, reass);
+         reass = NULL;
+         // if other worker created a context already work with the other copy
+         if (-2 == rv)
+           goto again;
+       }
+    }
+  else
+    {
+      reass->key.as_u64[0] = ~0;
+      reass->key.as_u64[1] = ~0;
+      reass->key.as_u64[2] = ~0;
+      reass->key.as_u64[3] = ~0;
+      reass->key.as_u64[4] = ~0;
+      reass->key.as_u64[5] = ~0;
     }
 
   return reass;
@@ -843,12 +856,13 @@ ip6_full_reass_insert_range_in_chain (vlib_main_t * vm,
 }
 
 always_inline ip6_full_reass_rc_t
-ip6_full_reass_update (vlib_main_t * vm, vlib_node_runtime_t * node,
-                      ip6_full_reass_main_t * rm,
-                      ip6_full_reass_per_thread_t * rt,
-                      ip6_full_reass_t * reass, u32 * bi0, u32 * next0,
-                      u32 * error0, ip6_frag_hdr_t * frag_hdr,
-                      bool is_custom_app, u32 * handoff_thread_idx)
+ip6_full_reass_update (vlib_main_t *vm, vlib_node_runtime_t *node,
+                      ip6_full_reass_main_t *rm,
+                      ip6_full_reass_per_thread_t *rt,
+                      ip6_full_reass_t *reass, u32 *bi0, u32 *next0,
+                      u32 *error0, ip6_frag_hdr_t *frag_hdr,
+                      bool is_custom_app, u32 *handoff_thread_idx,
+                      int skip_bihash)
 {
   int consumed = 0;
   vlib_buffer_t *fb = vlib_get_buffer (vm, *bi0);
@@ -956,6 +970,12 @@ check_if_done_maybe:
                                    ~0);
        }
     }
+  else if (skip_bihash)
+    {
+      // if this reassembly is not in bihash, then the packet must have been
+      // consumed
+      return IP6_FULL_REASS_RC_INTERNAL_ERROR;
+    }
   if (~0 != reass->last_packet_octet &&
       reass->data_len == reass->last_packet_octet + 1)
     {
@@ -973,6 +993,12 @@ check_if_done_maybe:
     }
   else
     {
+      if (skip_bihash)
+       {
+         // if this reassembly is not in bihash, it should've been an atomic
+         // fragment and thus finalized
+         return IP6_FULL_REASS_RC_INTERNAL_ERROR;
+       }
       if (consumed)
        {
          *bi0 = ~0;
@@ -1113,22 +1139,33 @@ ip6_full_reassembly_inline (vlib_main_t * vm,
              next0 = IP6_FULL_REASSEMBLY_NEXT_ICMP_ERROR;
              goto skip_reass;
            }
+
+         int skip_bihash = 0;
          ip6_full_reass_kv_t kv;
          u8 do_handoff = 0;
 
-         kv.k.as_u64[0] = ip0->src_address.as_u64[0];
-         kv.k.as_u64[1] = ip0->src_address.as_u64[1];
-         kv.k.as_u64[2] = ip0->dst_address.as_u64[0];
-         kv.k.as_u64[3] = ip0->dst_address.as_u64[1];
-         kv.k.as_u64[4] =
-           ((u64) vec_elt (ip6_main.fib_index_by_sw_if_index,
-                           vnet_buffer (b0)->sw_if_index[VLIB_RX])) << 32 |
-           (u64) frag_hdr->identification;
-         kv.k.as_u64[5] = ip0->protocol;
+         if (0 == ip6_frag_hdr_offset (frag_hdr) &&
+             !ip6_frag_hdr_more (frag_hdr))
+           {
+             // this is atomic fragment and needs to be processed separately
+             skip_bihash = 1;
+           }
+         else
+           {
+             kv.k.as_u64[0] = ip0->src_address.as_u64[0];
+             kv.k.as_u64[1] = ip0->src_address.as_u64[1];
+             kv.k.as_u64[2] = ip0->dst_address.as_u64[0];
+             kv.k.as_u64[3] = ip0->dst_address.as_u64[1];
+             kv.k.as_u64[4] =
+               ((u64) vec_elt (ip6_main.fib_index_by_sw_if_index,
+                               vnet_buffer (b0)->sw_if_index[VLIB_RX]))
+                 << 32 |
+               (u64) frag_hdr->identification;
+             kv.k.as_u64[5] = ip0->protocol;
+           }
 
-         ip6_full_reass_t *reass =
-           ip6_full_reass_find_or_create (vm, node, rm, rt, &kv, &icmp_bi,
-                                          &do_handoff);
+         ip6_full_reass_t *reass = ip6_full_reass_find_or_create (
+           vm, node, rm, rt, &kv, &icmp_bi, &do_handoff, skip_bihash);
 
          if (reass)
            {
@@ -1148,9 +1185,9 @@ ip6_full_reassembly_inline (vlib_main_t * vm,
            {
              u32 handoff_thread_idx;
              u32 counter = ~0;
-             switch (ip6_full_reass_update
-                     (vm, node, rm, rt, reass, &bi0, &next0, &error0,
-                      frag_hdr, is_custom_app, &handoff_thread_idx))
+             switch (ip6_full_reass_update (
+               vm, node, rm, rt, reass, &bi0, &next0, &error0, frag_hdr,
+               is_custom_app, &handoff_thread_idx, skip_bihash))
                {
                case IP6_FULL_REASS_RC_OK:
                  /* nothing to do here */