NAT44: fix ICMP virtual fragmentation reassembly (VPP-1466)

Change-Id: I8006bca02948d9121f474a3d14f0576747bb3c51
Signed-off-by: Matus Fabian <matfabia@cisco.com>

diff --git a/src/plugins/nat/in2out.c b/src/plugins/nat/in2out.c
index b99aef3..cb16981 100755 (executable)
--- a/src/plugins/nat/in2out.c
+++ b/src/plugins/nat/in2out.c
@@ -952,8 +952,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
            }
          else
            {
-             if (PREDICT_FALSE
-                 (proto0 == ~0 || proto0 == SNAT_PROTOCOL_ICMP))
+             if (PREDICT_FALSE (proto0 == ~0))
                {
                  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
                  goto trace00;
@@ -964,6 +963,12 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
                  next0 = SNAT_IN2OUT_NEXT_REASS;
                  goto trace00;
                }
+
+             if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+               {
+                 next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
+                 goto trace00;
+               }
            }
 
          key0.addr = ip0->src_address;
@@ -1131,8 +1136,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
            }
          else
            {
-             if (PREDICT_FALSE
-                 (proto1 == ~0 || proto1 == SNAT_PROTOCOL_ICMP))
+             if (PREDICT_FALSE (proto1 == ~0))
                {
                  next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
                  goto trace01;
@@ -1143,6 +1147,12 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
                  next1 = SNAT_IN2OUT_NEXT_REASS;
                  goto trace01;
                }
+
+             if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
+               {
+                 next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
+                 goto trace01;
+               }
            }
 
          key1.addr = ip1->src_address;
@@ -1346,8 +1356,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
            }
          else
            {
-             if (PREDICT_FALSE
-                 (proto0 == ~0 || proto0 == SNAT_PROTOCOL_ICMP))
+             if (PREDICT_FALSE (proto0 == ~0))
                {
                  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
                  goto trace0;
@@ -1358,6 +1367,12 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
                  next0 = SNAT_IN2OUT_NEXT_REASS;
                  goto trace0;
                }
+
+             if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+               {
+                 next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
+                 goto trace0;
+               }
            }
 
          key0.addr = ip0->src_address;
@@ -1672,6 +1687,7 @@ nat44_in2out_reass_node_fn (vlib_main_t * vm,
          nat_reass_ip4_t *reass0;
          udp_header_t *udp0;
          tcp_header_t *tcp0;
+         icmp46_header_t *icmp0;
          snat_session_key_t key0;
          clib_bihash_kv_8_8_t kv0, value0;
          snat_session_t *s0 = 0;
@@ -1704,6 +1720,7 @@ nat44_in2out_reass_node_fn (vlib_main_t * vm,
          ip0 = (ip4_header_t *) vlib_buffer_get_current (b0);
          udp0 = ip4_next_header (ip0);
          tcp0 = (tcp_header_t *) udp0;
+         icmp0 = (icmp46_header_t *) udp0;
          proto0 = ip_proto_to_snat_proto (ip0->protocol);
 
          reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
@@ -1722,6 +1739,25 @@ nat44_in2out_reass_node_fn (vlib_main_t * vm,
 
          if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
            {
+             if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+               {
+                 next0 = icmp_in2out_slow_path
+                   (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
+                    next0, now, thread_index, &s0);
+
+                 if (PREDICT_TRUE (next0 != SNAT_IN2OUT_NEXT_DROP))
+                   {
+                     if (s0)
+                       reass0->sess_index = s0 - per_thread_data->sessions;
+                     else
+                       reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
+                     nat_ip4_reass_get_frags (reass0,
+                                              &fragments_to_loopback);
+                   }
+
+                 goto trace0;
+               }
+
              key0.addr = ip0->src_address;
              key0.port = udp0->src_port;
              key0.protocol = proto0;

diff --git a/src/plugins/nat/in2out_ed.c b/src/plugins/nat/in2out_ed.c
index 8db53c0..f9f8d77 100644 (file)
--- a/src/plugins/nat/in2out_ed.c
+++ b/src/plugins/nat/in2out_ed.c
@@ -1960,11 +1960,8 @@ nat44_ed_in2out_reass_node_fn_inline (vlib_main_t * vm,
            }
 
          /* Hairpinning */
-         if (PREDICT_TRUE (proto0 != SNAT_PROTOCOL_ICMP))
-           nat44_reass_hairpinning (sm, b0, ip0, s0->out2in.port,
-                                    s0->ext_host_port, proto0, 1);
-         else
-           snat_icmp_hairpinning (sm, b0, ip0, icmp0, 1);
+         nat44_reass_hairpinning (sm, b0, ip0, s0->out2in.port,
+                                  s0->ext_host_port, proto0, 1);
 
          /* Accounting */
          nat44_session_update_counters (s0, now,

diff --git a/src/plugins/nat/nat44_hairpinning.c b/src/plugins/nat/nat44_hairpinning.c
index c07427d..09ea419 100644 (file)
--- a/src/plugins/nat/nat44_hairpinning.c
+++ b/src/plugins/nat/nat44_hairpinning.c
@@ -286,39 +286,6 @@ snat_icmp_hairpinning (snat_main_t * sm,
     }
   else
     {
-      if (!is_ed)
-       {
-         icmp_echo_header_t *echo0 = (icmp_echo_header_t *) (icmp0 + 1);
-         u16 icmp_id0 = echo0->identifier;
-         key0.addr = ip0->dst_address;
-         key0.port = icmp_id0;
-         key0.protocol = SNAT_PROTOCOL_ICMP;
-         key0.fib_index = sm->outside_fib_index;
-         kv0.key = key0.as_u64;
-         if (sm->num_workers > 1)
-           ti =
-             (clib_net_to_host_u16 (icmp_id0) - 1024) / sm->port_per_thread;
-         else
-           ti = sm->num_workers;
-         int rv =
-           clib_bihash_search_8_8 (&sm->per_thread_data[ti].out2in, &kv0,
-                                   &value0);
-         if (!rv)
-           {
-             si = value0.value;
-             s0 = pool_elt_at_index (sm->per_thread_data[ti].sessions, si);
-             new_dst_addr0 = s0->in2out.addr.as_u32;
-             vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
-             echo0->identifier = s0->in2out.port;
-             sum0 = icmp0->checksum;
-             sum0 = ip_csum_update (sum0, icmp_id0, s0->in2out.port,
-                                    icmp_echo_header_t, identifier);
-             icmp0->checksum = ip_csum_fold (sum0);
-             goto change_addr;
-           }
-         ti = 0;
-       }
-
       key0.addr = ip0->dst_address;
       key0.port = 0;
       key0.protocol = 0;
@@ -327,7 +294,44 @@ snat_icmp_hairpinning (snat_main_t * sm,
 
       if (clib_bihash_search_8_8
          (&sm->static_mapping_by_external, &kv0, &value0))
-       return 1;
+       {
+         if (!is_ed)
+           {
+             icmp_echo_header_t *echo0 = (icmp_echo_header_t *) (icmp0 + 1);
+             u16 icmp_id0 = echo0->identifier;
+             key0.addr = ip0->dst_address;
+             key0.port = icmp_id0;
+             key0.protocol = SNAT_PROTOCOL_ICMP;
+             key0.fib_index = sm->outside_fib_index;
+             kv0.key = key0.as_u64;
+             if (sm->num_workers > 1)
+               ti =
+                 (clib_net_to_host_u16 (icmp_id0) -
+                  1024) / sm->port_per_thread;
+             else
+               ti = sm->num_workers;
+             int rv =
+               clib_bihash_search_8_8 (&sm->per_thread_data[ti].out2in, &kv0,
+                                       &value0);
+             if (!rv)
+               {
+                 si = value0.value;
+                 s0 =
+                   pool_elt_at_index (sm->per_thread_data[ti].sessions, si);
+                 new_dst_addr0 = s0->in2out.addr.as_u32;
+                 vnet_buffer (b0)->sw_if_index[VLIB_TX] =
+                   s0->in2out.fib_index;
+                 echo0->identifier = s0->in2out.port;
+                 sum0 = icmp0->checksum;
+                 sum0 = ip_csum_update (sum0, icmp_id0, s0->in2out.port,
+                                        icmp_echo_header_t, identifier);
+                 icmp0->checksum = ip_csum_fold (sum0);
+                 goto change_addr;
+               }
+           }
+
+         return 1;
+       }
 
       m0 = pool_elt_at_index (sm->static_mappings, value0.value);
 

diff --git a/src/plugins/nat/out2in.c b/src/plugins/nat/out2in.c
index eeecf16..c4d1fbf 100755 (executable)
--- a/src/plugins/nat/out2in.c
+++ b/src/plugins/nat/out2in.c
@@ -775,17 +775,17 @@ snat_out2in_node_fn (vlib_main_t * vm,
              goto trace0;
            }
 
-         if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+         if (PREDICT_FALSE (ip4_is_fragment (ip0)))
            {
-             next0 = icmp_out2in_slow_path
-               (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
-                next0, now, thread_index, &s0);
+             next0 = SNAT_OUT2IN_NEXT_REASS;
              goto trace0;
            }
 
-         if (PREDICT_FALSE (ip4_is_fragment (ip0)))
+         if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
            {
-             next0 = SNAT_OUT2IN_NEXT_REASS;
+             next0 = icmp_out2in_slow_path
+               (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
+                next0, now, thread_index, &s0);
              goto trace0;
            }
 
@@ -936,17 +936,17 @@ snat_out2in_node_fn (vlib_main_t * vm,
              goto trace1;
            }
 
-         if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
+         if (PREDICT_FALSE (ip4_is_fragment (ip1)))
            {
-             next1 = icmp_out2in_slow_path
-               (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
-                next1, now, thread_index, &s1);
+             next1 = SNAT_OUT2IN_NEXT_REASS;
              goto trace1;
            }
 
-         if (PREDICT_FALSE (ip4_is_fragment (ip1)))
+         if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
            {
-             next1 = SNAT_OUT2IN_NEXT_REASS;
+             next1 = icmp_out2in_slow_path
+               (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
+                next1, now, thread_index, &s1);
              goto trace1;
            }
 
@@ -1134,17 +1134,17 @@ snat_out2in_node_fn (vlib_main_t * vm,
              goto trace00;
            }
 
-         if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+         if (PREDICT_FALSE (ip4_is_fragment (ip0)))
            {
-             next0 = icmp_out2in_slow_path
-               (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
-                next0, now, thread_index, &s0);
+             next0 = SNAT_OUT2IN_NEXT_REASS;
              goto trace00;
            }
 
-         if (PREDICT_FALSE (ip4_is_fragment (ip0)))
+         if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
            {
-             next0 = SNAT_OUT2IN_NEXT_REASS;
+             next0 = icmp_out2in_slow_path
+               (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
+                next0, now, thread_index, &s0);
              goto trace00;
            }
 
@@ -1336,6 +1336,7 @@ nat44_out2in_reass_node_fn (vlib_main_t * vm,
          nat_reass_ip4_t *reass0;
          udp_header_t *udp0;
          tcp_header_t *tcp0;
+         icmp46_header_t *icmp0;
          snat_session_key_t key0, sm0;
          clib_bihash_kv_8_8_t kv0, value0;
          snat_session_t *s0 = 0;
@@ -1369,6 +1370,7 @@ nat44_out2in_reass_node_fn (vlib_main_t * vm,
          ip0 = (ip4_header_t *) vlib_buffer_get_current (b0);
          udp0 = ip4_next_header (ip0);
          tcp0 = (tcp_header_t *) udp0;
+         icmp0 = (icmp46_header_t *) udp0;
          proto0 = ip_proto_to_snat_proto (ip0->protocol);
 
          reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
@@ -1387,6 +1389,26 @@ nat44_out2in_reass_node_fn (vlib_main_t * vm,
 
          if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
            {
+             if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+               {
+                 next0 = icmp_out2in_slow_path
+                   (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
+                    next0, now, thread_index, &s0);
+
+                 if (PREDICT_TRUE (next0 != SNAT_OUT2IN_NEXT_DROP))
+                   {
+                     if (s0)
+                       reass0->sess_index = s0 - per_thread_data->sessions;
+                     else
+                       reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
+                     reass0->thread_index = thread_index;
+                     nat_ip4_reass_get_frags (reass0,
+                                              &fragments_to_loopback);
+                   }
+
+                 goto trace0;
+               }
+
              key0.addr = ip0->dst_address;
              key0.port = udp0->dst_port;
              key0.protocol = proto0;

diff --git a/test/test_nat.py b/test/test_nat.py
index e9e7dfa..e26aa27 100644 (file)
--- a/test/test_nat.py
+++ b/test/test_nat.py
@@ -3335,86 +3335,36 @@ class TestNAT44(MethodHolder):
         self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
                                                   is_inside=0)
 
-        data = "A" * 4 + "B" * 16 + "C" * 3
-        self.tcp_port_in = random.randint(1025, 65535)
-
-        reass = self.vapi.nat_reass_dump()
-        reass_n_start = len(reass)
-
-        # in2out
-        pkts = self.create_stream_frag(self.pg0,
-                                       self.pg1.remote_ip4,
-                                       self.tcp_port_in,
-                                       20,
-                                       data)
-        self.pg0.add_stream(pkts)
-        self.pg_enable_capture(self.pg_interfaces)
-        self.pg_start()
-        frags = self.pg1.get_capture(len(pkts))
-        p = self.reass_frags_and_verify(frags,
-                                        self.nat_addr,
-                                        self.pg1.remote_ip4)
-        self.assertEqual(p[TCP].dport, 20)
-        self.assertNotEqual(p[TCP].sport, self.tcp_port_in)
-        self.tcp_port_out = p[TCP].sport
-        self.assertEqual(data, p[Raw].load)
-
-        # out2in
-        pkts = self.create_stream_frag(self.pg1,
-                                       self.nat_addr,
-                                       20,
-                                       self.tcp_port_out,
-                                       data)
-        self.pg1.add_stream(pkts)
-        self.pg_enable_capture(self.pg_interfaces)
-        self.pg_start()
-        frags = self.pg0.get_capture(len(pkts))
-        p = self.reass_frags_and_verify(frags,
-                                        self.pg1.remote_ip4,
-                                        self.pg0.remote_ip4)
-        self.assertEqual(p[TCP].sport, 20)
-        self.assertEqual(p[TCP].dport, self.tcp_port_in)
-        self.assertEqual(data, p[Raw].load)
-
-        reass = self.vapi.nat_reass_dump()
-        reass_n_end = len(reass)
-
-        self.assertEqual(reass_n_end - reass_n_start, 2)
+        self.frag_in_order(proto=IP_PROTOS.tcp)
+        self.frag_in_order(proto=IP_PROTOS.udp)
+        self.frag_in_order(proto=IP_PROTOS.icmp)
 
     def test_reass_hairpinning(self):
         """ NAT44 fragments hairpinning """
 
-        server = self.pg0.remote_hosts[1]
-        host_in_port = random.randint(1025, 65535)
-        server_in_port = random.randint(1025, 65535)
-        server_out_port = random.randint(1025, 65535)
-        data = "A" * 4 + "B" * 16 + "C" * 3
+        self.server = self.pg0.remote_hosts[1]
+        self.host_in_port = random.randint(1025, 65535)
+        self.server_in_port = random.randint(1025, 65535)
+        self.server_out_port = random.randint(1025, 65535)
 
         self.nat44_add_address(self.nat_addr)
         self.vapi.nat44_interface_add_del_feature(self.pg0.sw_if_index)
         self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
                                                   is_inside=0)
         # add static mapping for server
-        self.nat44_add_static_mapping(server.ip4, self.nat_addr,
-                                      server_in_port, server_out_port,
+        self.nat44_add_static_mapping(self.server.ip4, self.nat_addr,
+                                      self.server_in_port,
+                                      self.server_out_port,
                                       proto=IP_PROTOS.tcp)
+        self.nat44_add_static_mapping(self.server.ip4, self.nat_addr,
+                                      self.server_in_port,
+                                      self.server_out_port,
+                                      proto=IP_PROTOS.udp)
+        self.nat44_add_static_mapping(self.server.ip4, self.nat_addr)
 
-        # send packet from host to server
-        pkts = self.create_stream_frag(self.pg0,
-                                       self.nat_addr,
-                                       host_in_port,
-                                       server_out_port,
-                                       data)
-        self.pg0.add_stream(pkts)
-        self.pg_enable_capture(self.pg_interfaces)
-        self.pg_start()
-        frags = self.pg0.get_capture(len(pkts))
-        p = self.reass_frags_and_verify(frags,
-                                        self.nat_addr,
-                                        server.ip4)
-        self.assertNotEqual(p[TCP].sport, host_in_port)
-        self.assertEqual(p[TCP].dport, server_in_port)
-        self.assertEqual(data, p[Raw].load)
+        self.reass_hairpinning(proto=IP_PROTOS.tcp)
+        self.reass_hairpinning(proto=IP_PROTOS.udp)
+        self.reass_hairpinning(proto=IP_PROTOS.icmp)
 
     def test_frag_out_of_order(self):
         """ NAT44 translate fragments arriving out of order """
@@ -3424,45 +3374,9 @@ class TestNAT44(MethodHolder):
         self.vapi.nat44_interface_add_del_feature(self.pg1.sw_if_index,
                                                   is_inside=0)
 
-        data = "A" * 4 + "B" * 16 + "C" * 3
-        random.randint(1025, 65535)
-
-        # in2out
-        pkts = self.create_stream_frag(self.pg0,
-                                       self.pg1.remote_ip4,
-                                       self.tcp_port_in,
-                                       20,
-                                       data)
-        pkts.reverse()
-        self.pg0.add_stream(pkts)
-        self.pg_enable_capture(self.pg_interfaces)
-        self.pg_start()
-        frags = self.pg1.get_capture(len(pkts))
-        p = self.reass_frags_and_verify(frags,
-                                        self.nat_addr,
-                                        self.pg1.remote_ip4)
-        self.assertEqual(p[TCP].dport, 20)
-        self.assertNotEqual(p[TCP].sport, self.tcp_port_in)
-        self.tcp_port_out = p[TCP].sport
-        self.assertEqual(data, p[Raw].load)
-
-        # out2in
-        pkts = self.create_stream_frag(self.pg1,
-                                       self.nat_addr,
-                                       20,
-                                       self.tcp_port_out,
-                                       data)
-        pkts.reverse()
-        self.pg1.add_stream(pkts)
-        self.pg_enable_capture(self.pg_interfaces)
-        self.pg_start()
-        frags = self.pg0.get_capture(len(pkts))
-        p = self.reass_frags_and_verify(frags,
-                                        self.pg1.remote_ip4,
-                                        self.pg0.remote_ip4)
-        self.assertEqual(p[TCP].sport, 20)
-        self.assertEqual(p[TCP].dport, self.tcp_port_in)
-        self.assertEqual(data, p[Raw].load)
+        self.frag_out_of_order(proto=IP_PROTOS.tcp)
+        self.frag_out_of_order(proto=IP_PROTOS.udp)
+        self.frag_out_of_order(proto=IP_PROTOS.icmp)
 
     def test_port_restricted(self):
         """ Port restricted NAT44 (MAP-E CE) """
@@ -3971,8 +3885,7 @@ class TestNAT44EndpointDependent(MethodHolder):
                                       self.server_in_port,
                                       self.server_out_port,
                                       proto=IP_PROTOS.udp)
-        self.nat44_add_static_mapping(self.server.ip4, self.nat_addr,
-                                      proto=IP_PROTOS.icmp)
+        self.nat44_add_static_mapping(self.server.ip4, self.nat_addr)
 
         self.reass_hairpinning(proto=IP_PROTOS.tcp)
         self.reass_hairpinning(proto=IP_PROTOS.udp)