FD.io VPP  v18.07.1-19-g511ce25
Vector Packet Processing
nat66_out2in.c
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1 /*
2  * Copyright (c) 2018 Cisco and/or its affiliates.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at:
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 /**
16  * @file
17  * @brief NAT66 outside to inside network translation
18  */
19 
20 #include <nat/nat66.h>
21 #include <vnet/ip/ip6_to_ip4.h>
22 #include <vnet/fib/fib_table.h>
23 
24 typedef struct
25 {
29 
30 static u8 *
31 format_nat66_out2in_trace (u8 * s, va_list * args)
32 {
33  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
34  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
35  nat66_out2in_trace_t *t = va_arg (*args, nat66_out2in_trace_t *);
36 
37  s =
38  format (s, "NAT66-out2in: sw_if_index %d, next index %d", t->sw_if_index,
39  t->next_index);
40 
41  return s;
42 }
43 
45 
46 #define foreach_nat66_out2in_error \
47 _(OUT2IN_PACKETS, "good out2in packets processed") \
48 _(NO_TRANSLATION, "no translation") \
49 _(UNKNOWN, "unknown")
50 
51 typedef enum
52 {
53 #define _(sym,str) NAT66_OUT2IN_ERROR_##sym,
55 #undef _
58 
59 static char *nat66_out2in_error_strings[] = {
60 #define _(sym,string) string,
62 #undef _
63 };
64 
65 typedef enum
66 {
71 
72 static inline uword
74  vlib_frame_t * frame)
75 {
76  u32 n_left_from, *from, *to_next;
77  nat66_out2in_next_t next_index;
78  u32 pkts_processed = 0;
79  u32 thread_index = vm->thread_index;
80  nat66_main_t *nm = &nat66_main;
81 
82  from = vlib_frame_vector_args (frame);
83  n_left_from = frame->n_vectors;
84  next_index = node->cached_next_index;
85 
86  while (n_left_from > 0)
87  {
88  u32 n_left_to_next;
89 
90  vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
91 
92  while (n_left_from > 0 && n_left_to_next > 0)
93  {
94  u32 bi0;
95  vlib_buffer_t *b0;
97  ip6_header_t *ip60;
98  u16 l4_offset0, frag_offset0;
99  u8 l4_protocol0;
101  u32 sw_if_index0, fib_index0;
102  udp_header_t *udp0;
103  tcp_header_t *tcp0;
104  icmp46_header_t *icmp0;
105  u16 *checksum0 = 0;
106  ip_csum_t csum0;
107 
108  /* speculatively enqueue b0 to the current next frame */
109  bi0 = from[0];
110  to_next[0] = bi0;
111  from += 1;
112  to_next += 1;
113  n_left_from -= 1;
114  n_left_to_next -= 1;
115 
116  b0 = vlib_get_buffer (vm, bi0);
117  ip60 = vlib_buffer_get_current (b0);
118 
119  if (PREDICT_FALSE
120  (ip6_parse
121  (ip60, b0->current_length, &l4_protocol0, &l4_offset0,
122  &frag_offset0)))
123  {
124  next0 = NAT66_OUT2IN_NEXT_DROP;
125  b0->error = node->errors[NAT66_OUT2IN_ERROR_UNKNOWN];
126  goto trace0;
127  }
128 
129  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
130  fib_index0 =
132  sw_if_index0);
133 
134  sm0 = nat66_static_mapping_get (&ip60->dst_address, fib_index0, 0);
135  if (PREDICT_FALSE (!sm0))
136  {
137  goto trace0;
138  }
139 
140  if (l4_protocol0 == IP_PROTOCOL_UDP)
141  {
142  udp0 = (udp_header_t *) u8_ptr_add (ip60, l4_offset0);
143  checksum0 = &udp0->checksum;
144  }
145  else if (l4_protocol0 == IP_PROTOCOL_TCP)
146  {
147  tcp0 = (tcp_header_t *) u8_ptr_add (ip60, l4_offset0);
148  checksum0 = &tcp0->checksum;
149  }
150  else if (l4_protocol0 == IP_PROTOCOL_ICMP6)
151  {
152  icmp0 = (icmp46_header_t *) u8_ptr_add (ip60, l4_offset0);
153  checksum0 = &icmp0->checksum;
154  }
155  else
156  goto skip_csum0;
157 
158  csum0 = ip_csum_sub_even (*checksum0, ip60->dst_address.as_u64[0]);
159  csum0 = ip_csum_sub_even (csum0, ip60->dst_address.as_u64[1]);
160  csum0 = ip_csum_add_even (csum0, sm0->l_addr.as_u64[0]);
161  csum0 = ip_csum_add_even (csum0, sm0->l_addr.as_u64[1]);
162  *checksum0 = ip_csum_fold (csum0);
163 
164  skip_csum0:
165  ip60->dst_address.as_u64[0] = sm0->l_addr.as_u64[0];
166  ip60->dst_address.as_u64[1] = sm0->l_addr.as_u64[1];
167  vnet_buffer (b0)->sw_if_index[VLIB_TX] = sm0->fib_index;
168 
170  thread_index, sm0 - nm->sm, 1,
172  b0));
173 
174  trace0:
176  && (b0->flags & VLIB_BUFFER_IS_TRACED)))
177  {
179  vlib_add_trace (vm, node, b0, sizeof (*t));
180  t->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
181  t->next_index = next0;
182  }
183 
184  pkts_processed += next0 != NAT66_OUT2IN_NEXT_DROP;
185 
186  /* verify speculative enqueue, maybe switch current next frame */
187  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
188  n_left_to_next, bi0, next0);
189  }
190  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
191  }
192 
194  NAT66_OUT2IN_ERROR_OUT2IN_PACKETS,
195  pkts_processed);
196  return frame->n_vectors;
197 }
198 
199 /* *INDENT-OFF* */
201  .function = nat66_out2in_node_fn,
202  .name = "nat66-out2in",
203  .vector_size = sizeof (u32),
204  .format_trace = format_nat66_out2in_trace,
205  .type = VLIB_NODE_TYPE_INTERNAL,
207  .error_strings = nat66_out2in_error_strings,
208  .n_next_nodes = NAT66_OUT2IN_N_NEXT,
209  /* edit / add dispositions here */
210  .next_nodes = {
211  [NAT66_OUT2IN_NEXT_DROP] = "error-drop",
212  [NAT66_OUT2IN_NEXT_IP6_LOOKUP] = "ip6-lookup",
213  },
214 };
215 /* *INDENT-ON* */
216 
218 
219 /*
220  * fd.io coding-style-patch-verification: ON
221  *
222  * Local Variables:
223  * eval: (c-set-style "gnu")
224  * End:
225  */
#define CLIB_UNUSED(x)
Definition: clib.h:79
static void vlib_increment_combined_counter(vlib_combined_counter_main_t *cm, u32 thread_index, u32 index, u64 n_packets, u64 n_bytes)
Increment a combined counter.
Definition: counter.h:213
u64 as_u64[2]
Definition: ip6_packet.h:51
u32 fib_table_get_index_for_sw_if_index(fib_protocol_t proto, u32 sw_if_index)
Get the index of the FIB bound to the interface.
Definition: fib_table.c:948
u32 thread_index
Definition: main.h:179
uword ip_csum_t
Definition: ip_packet.h:181
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:419
vlib_error_t * errors
Vector of errors for this node.
Definition: node.h:451
static uword vlib_buffer_length_in_chain(vlib_main_t *vm, vlib_buffer_t *b)
Get length in bytes of the buffer chain.
Definition: buffer_funcs.h:250
struct _tcp_header tcp_header_t
unsigned char u8
Definition: types.h:56
static u8 * format_nat66_out2in_trace(u8 *s, va_list *args)
Definition: nat66_out2in.c:31
nat66_main_t nat66_main
Definition: nat66.c:23
static_always_inline int ip6_parse(const ip6_header_t *ip6, u32 buff_len, u8 *l4_protocol, u16 *l4_offset, u16 *frag_hdr_offset)
Parse some useful information from IPv6 header.
Definition: ip6_to_ip4.h:59
unsigned int u32
Definition: types.h:88
static uword nat66_out2in_node_fn(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
Definition: nat66_out2in.c:73
static char * nat66_out2in_error_strings[]
Definition: nat66_out2in.c:59
u16 current_length
Nbytes between current data and the end of this buffer.
Definition: buffer.h:108
unsigned short u16
Definition: types.h:57
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:202
#define PREDICT_FALSE(x)
Definition: clib.h:105
#define vlib_validate_buffer_enqueue_x1(vm, node, next_index, to_next, n_left_to_next, bi0, next0)
Finish enqueueing one buffer forward in the graph.
Definition: buffer_node.h:218
#define vlib_get_next_frame(vm, node, next_index, vectors, n_vectors_left)
Get pointer to next frame vector data by (vlib_node_runtime_t, next_index).
Definition: node_funcs.h:364
vlib_error_t error
Error code for buffers to be enqueued to error handler.
Definition: buffer.h:135
static void vlib_node_increment_counter(vlib_main_t *vm, u32 node_index, u32 counter_index, u64 increment)
Definition: node_funcs.h:1168
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:153
u16 n_vectors
Definition: node.h:380
vlib_main_t * vm
Definition: buffer.c:294
#define ARRAY_LEN(x)
Definition: clib.h:59
void vlib_put_next_frame(vlib_main_t *vm, vlib_node_runtime_t *r, u32 next_index, u32 n_vectors_left)
Release pointer to next frame vector data.
Definition: main.c:454
u16 cached_next_index
Next frame index that vector arguments were last enqueued to last time this node ran.
Definition: node.h:492
VLIB_NODE_FUNCTION_MULTIARCH(nat66_out2in_node, nat66_out2in_node_fn)
static ip_csum_t ip_csum_sub_even(ip_csum_t c, ip_csum_t x)
Definition: ip_packet.h:209
IPv6 to IPv4 translation.
#define u8_ptr_add(ptr, index)
Definition: ip.h:68
static void * vlib_add_trace(vlib_main_t *vm, vlib_node_runtime_t *r, vlib_buffer_t *b, u32 n_data_bytes)
Definition: trace_funcs.h:55
struct _vlib_node_registration vlib_node_registration_t
ip6_address_t l_addr
Definition: nat66.h:27
Definition: defs.h:47
vlib_combined_counter_main_t session_counters
Session counters.
Definition: nat66.h:57
u64 uword
Definition: types.h:112
static void * vlib_frame_vector_args(vlib_frame_t *f)
Get pointer to frame vector data.
Definition: node_funcs.h:267
#define foreach_nat66_out2in_error
Definition: nat66_out2in.c:46
#define vnet_buffer(b)
Definition: buffer.h:360
nat66_static_mapping_t * sm
Static mapping pool.
Definition: nat66.h:51
u16 flags
Copy of main node flags.
Definition: node.h:486
#define VLIB_NODE_FLAG_TRACE
Definition: node.h:295
NAT66 global declarations.
nat66_static_mapping_t * nat66_static_mapping_get(ip6_address_t *addr, u32 fib_index, u8 is_local)
Definition: nat66.c:115
u32 flags
buffer flags: VLIB_BUFFER_FREE_LIST_INDEX_MASK: bits used to store free list index, VLIB_BUFFER_IS_TRACED: trace this buffer.
Definition: buffer.h:111
nat66_out2in_next_t
Definition: nat66_out2in.c:65
nat66_out2in_error_t
Definition: nat66_out2in.c:51
static vlib_buffer_t * vlib_get_buffer(vlib_main_t *vm, u32 buffer_index)
Translate buffer index into buffer pointer.
Definition: buffer_funcs.h:57
vlib_node_registration_t nat66_out2in_node
(constructor) VLIB_REGISTER_NODE (nat66_out2in_node)
Definition: nat66_out2in.c:44
static u16 ip_csum_fold(ip_csum_t c)
Definition: ip_packet.h:237
Definition: defs.h:46
static ip_csum_t ip_csum_add_even(ip_csum_t c, ip_csum_t x)
Definition: ip_packet.h:192
ip6_address_t dst_address
Definition: ip6_packet.h:347