FD.io VPP  v19.04.4-rc0-5-ge88582fac
Vector Packet Processing
ah_encrypt.c
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1 /*
2  * ah_encrypt.c : IPSec AH encrypt node
3  *
4  * Copyright (c) 2015 Cisco and/or its affiliates.
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at:
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 #include <vnet/vnet.h>
19 #include <vnet/api_errno.h>
20 #include <vnet/ip/ip.h>
21 
22 #include <vnet/ipsec/ipsec.h>
23 #include <vnet/ipsec/esp.h>
24 #include <vnet/ipsec/ah.h>
25 
26 #define foreach_ah_encrypt_next \
27  _ (DROP, "error-drop") \
28  _ (IP4_LOOKUP, "ip4-lookup") \
29  _ (IP6_LOOKUP, "ip6-lookup") \
30  _ (INTERFACE_OUTPUT, "interface-output")
31 
32 
33 #define _(v, s) AH_ENCRYPT_NEXT_##v,
34 typedef enum
35 {
37 #undef _
40 
41 #define foreach_ah_encrypt_error \
42  _(RX_PKTS, "AH pkts received") \
43  _(SEQ_CYCLED, "sequence number cycled")
44 
45 
46 typedef enum
47 {
48 #define _(sym,str) AH_ENCRYPT_ERROR_##sym,
50 #undef _
53 
54 static char *ah_encrypt_error_strings[] = {
55 #define _(sym,string) string,
57 #undef _
58 };
59 
60 typedef struct
61 {
68 
69 /* packet trace format function */
70 static u8 *
71 format_ah_encrypt_trace (u8 * s, va_list * args)
72 {
73  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
74  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
75  ah_encrypt_trace_t *t = va_arg (*args, ah_encrypt_trace_t *);
76 
77  s = format (s, "ah: sa-index %d spi %u seq %u:%u integrity %U",
78  t->sa_index, t->spi, t->seq_hi, t->seq_lo,
80  return s;
81 }
82 
85  vlib_node_runtime_t * node, vlib_frame_t * from_frame,
86  int is_ip6)
87 {
88  u32 n_left_from, *from, *to_next = 0, next_index, thread_index;
89  int icv_size = 0;
90  from = vlib_frame_vector_args (from_frame);
91  n_left_from = from_frame->n_vectors;
92  ipsec_main_t *im = &ipsec_main;
93  next_index = node->cached_next_index;
94  thread_index = vm->thread_index;
95 
96  while (n_left_from > 0)
97  {
98  u32 n_left_to_next;
99 
100  vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
101 
102  while (n_left_from > 0 && n_left_to_next > 0)
103  {
104  u32 i_bi0, next0;
105  vlib_buffer_t *i_b0 = 0;
106  u32 sa_index0;
107  ipsec_sa_t *sa0;
108  ip4_and_ah_header_t *ih0, *oh0 = 0;
109  ip6_and_ah_header_t *ih6_0, *oh6_0 = 0;
110  u8 ip_hdr_size;
111  u8 next_hdr_type;
112  u8 tos = 0;
113  u8 ttl = 0;
114  u8 hop_limit = 0;
115  u32 ip_version_traffic_class_and_flow_label = 0;
116 
117  i_bi0 = from[0];
118  from += 1;
119  n_left_from -= 1;
120  n_left_to_next -= 1;
121  next0 = AH_ENCRYPT_NEXT_DROP;
122 
123  i_b0 = vlib_get_buffer (vm, i_bi0);
124  to_next[0] = i_bi0;
125  to_next += 1;
126  sa_index0 = vnet_buffer (i_b0)->ipsec.sad_index;
127  sa0 = pool_elt_at_index (im->sad, sa_index0);
128 
129  if (PREDICT_FALSE (esp_seq_advance (sa0)))
130  {
131  i_b0->error = node->errors[AH_ENCRYPT_ERROR_SEQ_CYCLED];
132  goto trace;
133  }
135  (&ipsec_sa_counters, thread_index, sa_index0,
136  1, i_b0->current_length);
137 
138  ssize_t adv;
139  ih0 = vlib_buffer_get_current (i_b0);
140  ttl = ih0->ip4.ttl;
141  tos = ih0->ip4.tos;
142 
143  if (PREDICT_TRUE (ipsec_sa_is_set_IS_TUNNEL (sa0)))
144  {
145  if (is_ip6)
146  adv = -sizeof (ip6_and_ah_header_t);
147  else
148  adv = -sizeof (ip4_and_ah_header_t);
149  }
150  else
151  {
152  adv = -sizeof (ah_header_t);
153  }
154 
155  icv_size = sa0->integ_icv_size;
156  const u8 padding_len = ah_calc_icv_padding_len (icv_size, is_ip6);
157  adv -= padding_len;
158  /* transport mode save the eth header before it is overwritten */
159  if (PREDICT_FALSE (!ipsec_sa_is_set_IS_TUNNEL (sa0)))
160  {
162  ((u8 *) vlib_buffer_get_current (i_b0) -
163  sizeof (ethernet_header_t));
164  ethernet_header_t *oeh0 =
165  (ethernet_header_t *) ((u8 *) ieh0 + (adv - icv_size));
166  clib_memcpy_fast (oeh0, ieh0, sizeof (ethernet_header_t));
167  }
168 
169  vlib_buffer_advance (i_b0, adv - icv_size);
170 
171  if (is_ip6)
172  {
173  ih6_0 = (ip6_and_ah_header_t *) ih0;
174  ip_hdr_size = sizeof (ip6_header_t);
175  oh6_0 = vlib_buffer_get_current (i_b0);
176 
177  hop_limit = ih6_0->ip6.hop_limit;
178  ip_version_traffic_class_and_flow_label =
179  ih6_0->ip6.ip_version_traffic_class_and_flow_label;
180  if (PREDICT_TRUE (ipsec_sa_is_set_IS_TUNNEL (sa0)))
181  {
182  next_hdr_type = IP_PROTOCOL_IPV6;
183  }
184  else
185  {
186  next_hdr_type = ih6_0->ip6.protocol;
187  memmove (oh6_0, ih6_0, sizeof (ip6_header_t));
188  }
189 
190  oh6_0->ip6.protocol = IP_PROTOCOL_IPSEC_AH;
191  oh6_0->ip6.hop_limit = 0;
192  oh6_0->ip6.ip_version_traffic_class_and_flow_label = 0x60;
193  oh6_0->ah.reserved = 0;
194  oh6_0->ah.nexthdr = next_hdr_type;
195  oh6_0->ah.spi = clib_net_to_host_u32 (sa0->spi);
196  oh6_0->ah.seq_no = clib_net_to_host_u32 (sa0->seq);
197  oh6_0->ip6.payload_length =
198  clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, i_b0) -
199  sizeof (ip6_header_t));
200  oh6_0->ah.hdrlen =
201  (sizeof (ah_header_t) + icv_size + padding_len) / 4 - 2;
202  }
203  else
204  {
205  ip_hdr_size = sizeof (ip4_header_t);
206  oh0 = vlib_buffer_get_current (i_b0);
207  clib_memset (oh0, 0, sizeof (ip4_and_ah_header_t));
208 
209  if (PREDICT_TRUE (ipsec_sa_is_set_IS_TUNNEL (sa0)))
210  {
211  next_hdr_type = IP_PROTOCOL_IP_IN_IP;
212  }
213  else
214  {
215  next_hdr_type = ih0->ip4.protocol;
216  memmove (oh0, ih0, sizeof (ip4_header_t));
217  }
218 
219  oh0->ip4.length =
220  clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, i_b0));
221  oh0->ip4.ip_version_and_header_length = 0x45;
222  oh0->ip4.fragment_id = 0;
223  oh0->ip4.flags_and_fragment_offset = 0;
224  oh0->ip4.ttl = 0;
225  oh0->ip4.tos = 0;
226  oh0->ip4.protocol = IP_PROTOCOL_IPSEC_AH;
227  oh0->ah.spi = clib_net_to_host_u32 (sa0->spi);
228  oh0->ah.seq_no = clib_net_to_host_u32 (sa0->seq);
229  oh0->ip4.checksum = 0;
230  oh0->ah.nexthdr = next_hdr_type;
231  oh0->ah.hdrlen =
232  (sizeof (ah_header_t) + icv_size + padding_len) / 4 - 2;
233  }
234 
235 
236  if (PREDICT_TRUE (!is_ip6 && ipsec_sa_is_set_IS_TUNNEL (sa0) &&
237  !ipsec_sa_is_set_IS_TUNNEL_V6 (sa0)))
238  {
239  oh0->ip4.src_address.as_u32 = sa0->tunnel_src_addr.ip4.as_u32;
240  oh0->ip4.dst_address.as_u32 = sa0->tunnel_dst_addr.ip4.as_u32;
241 
242  next0 = sa0->dpo[IPSEC_PROTOCOL_AH].dpoi_next_node;
243  vnet_buffer (i_b0)->ip.adj_index[VLIB_TX] =
245  }
246  else if (is_ip6 && ipsec_sa_is_set_IS_TUNNEL (sa0) &&
247  ipsec_sa_is_set_IS_TUNNEL_V6 (sa0))
248  {
249  oh6_0->ip6.src_address.as_u64[0] =
250  sa0->tunnel_src_addr.ip6.as_u64[0];
251  oh6_0->ip6.src_address.as_u64[1] =
252  sa0->tunnel_src_addr.ip6.as_u64[1];
253  oh6_0->ip6.dst_address.as_u64[0] =
254  sa0->tunnel_dst_addr.ip6.as_u64[0];
255  oh6_0->ip6.dst_address.as_u64[1] =
256  sa0->tunnel_dst_addr.ip6.as_u64[1];
257 
258  next0 = sa0->dpo[IPSEC_PROTOCOL_AH].dpoi_next_node;
259  vnet_buffer (i_b0)->ip.adj_index[VLIB_TX] =
261  }
262 
263  u8 sig[64];
264 
265  u8 *digest =
266  vlib_buffer_get_current (i_b0) + ip_hdr_size +
267  sizeof (ah_header_t);
268  clib_memset (digest, 0, icv_size);
269 
270  unsigned size = hmac_calc (vm, sa0, vlib_buffer_get_current (i_b0),
271  i_b0->current_length, sig);
272 
273  memcpy (digest, sig, size);
274  if (is_ip6)
275  {
276  oh6_0->ip6.hop_limit = hop_limit;
277  oh6_0->ip6.ip_version_traffic_class_and_flow_label =
278  ip_version_traffic_class_and_flow_label;
279  }
280  else
281  {
282  oh0->ip4.ttl = ttl;
283  oh0->ip4.tos = tos;
284  oh0->ip4.checksum = ip4_header_checksum (&oh0->ip4);
285  }
286 
287  if (!ipsec_sa_is_set_IS_TUNNEL (sa0))
288  {
289  next0 = AH_ENCRYPT_NEXT_INTERFACE_OUTPUT;
290  vlib_buffer_advance (i_b0, -sizeof (ethernet_header_t));
291  }
292 
293  trace:
294  if (PREDICT_FALSE (i_b0->flags & VLIB_BUFFER_IS_TRACED))
295  {
296  ah_encrypt_trace_t *tr =
297  vlib_add_trace (vm, node, i_b0, sizeof (*tr));
298  tr->spi = sa0->spi;
299  tr->seq_lo = sa0->seq;
300  tr->seq_hi = sa0->seq_hi;
301  tr->integ_alg = sa0->integ_alg;
302  tr->sa_index = sa_index0;
303  }
304 
305  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
306  to_next, n_left_to_next, i_bi0,
307  next0);
308  }
309  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
310  }
312  AH_ENCRYPT_ERROR_RX_PKTS,
313  from_frame->n_vectors);
314 
315  return from_frame->n_vectors;
316 }
317 
319  vlib_node_runtime_t * node,
320  vlib_frame_t * from_frame)
321 {
322  return ah_encrypt_inline (vm, node, from_frame, 0 /* is_ip6 */ );
323 }
324 
325 /* *INDENT-OFF* */
327  .name = "ah4-encrypt",
328  .vector_size = sizeof (u32),
329  .format_trace = format_ah_encrypt_trace,
330  .type = VLIB_NODE_TYPE_INTERNAL,
331 
332  .n_errors = ARRAY_LEN(ah_encrypt_error_strings),
333  .error_strings = ah_encrypt_error_strings,
334 
335  .n_next_nodes = AH_ENCRYPT_N_NEXT,
336  .next_nodes = {
337 #define _(s,n) [AH_ENCRYPT_NEXT_##s] = n,
339 #undef _
340  },
341 };
342 /* *INDENT-ON* */
343 
345  vlib_node_runtime_t * node,
346  vlib_frame_t * from_frame)
347 {
348  return ah_encrypt_inline (vm, node, from_frame, 1 /* is_ip6 */ );
349 }
350 
351 /* *INDENT-OFF* */
353  .name = "ah6-encrypt",
354  .vector_size = sizeof (u32),
355  .format_trace = format_ah_encrypt_trace,
356  .type = VLIB_NODE_TYPE_INTERNAL,
357 
358  .n_errors = ARRAY_LEN(ah_encrypt_error_strings),
359  .error_strings = ah_encrypt_error_strings,
360 
361  .n_next_nodes = AH_ENCRYPT_N_NEXT,
362  .next_nodes = {
363 #define _(s,n) [AH_ENCRYPT_NEXT_##s] = n,
365 #undef _
366  },
367 };
368 /* *INDENT-ON* */
369 
370 /*
371  * fd.io coding-style-patch-verification: ON
372  *
373  * Local Variables:
374  * eval: (c-set-style "gnu")
375  * End:
376  */
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:124
u8 * format_ipsec_integ_alg(u8 *s, va_list *args)
Definition: ipsec_format.c:109
static vlib_cli_command_t trace
(constructor) VLIB_CLI_COMMAND (trace)
Definition: vlib_api_cli.c:862
#define CLIB_UNUSED(x)
Definition: clib.h:82
ip46_address_t tunnel_src_addr
Definition: ipsec_sa.h:156
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:220
#define PREDICT_TRUE(x)
Definition: clib.h:112
ipsec_integ_alg_t
Definition: ipsec_sa.h:60
#define clib_memcpy_fast(a, b, c)
Definition: string.h:81
clib_memset(h->entries, 0, sizeof(h->entries[0]) *entries)
ipsec_integ_alg_t integ_alg
Definition: ipsec_sa.h:153
u32 thread_index
Definition: main.h:197
u16 current_length
Nbytes between current data and the end of this buffer.
Definition: buffer.h:113
vlib_node_registration_t ah6_encrypt_node
(constructor) VLIB_REGISTER_NODE (ah6_encrypt_node)
Definition: ah_encrypt.c:352
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:424
#define VLIB_NODE_FN(node)
Definition: node.h:201
vlib_error_t * errors
Vector of errors for this node.
Definition: node.h:468
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:366
unsigned char u8
Definition: types.h:56
u32 seq_hi
Definition: ipsec_sa.h:123
static int esp_seq_advance(ipsec_sa_t *sa)
Definition: esp.h:80
static uword ah_encrypt_inline(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame, int is_ip6)
Definition: ah_encrypt.c:84
ipsec_main_t ipsec_main
Definition: ipsec.c:28
#define always_inline
Definition: clib.h:98
unsigned int u32
Definition: types.h:88
ipsec_integ_alg_t integ_alg
Definition: ah_encrypt.c:66
static u8 ah_calc_icv_padding_len(u8 icv_size, int is_ipv6)
Definition: ah.h:47
vlib_error_t error
Error code for buffers to be enqueued to error handler.
Definition: buffer.h:136
#define pool_elt_at_index(p, i)
Returns pointer to element at given index.
Definition: pool.h:514
uword size
static unsigned int hmac_calc(vlib_main_t *vm, ipsec_sa_t *sa, u8 *data, int data_len, u8 *signature)
Definition: esp.h:106
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:229
#define PREDICT_FALSE(x)
Definition: clib.h:111
ah_encrypt_next_t
Definition: ah_encrypt.c:34
vlib_node_registration_t ah4_encrypt_node
(constructor) VLIB_REGISTER_NODE (ah4_encrypt_node)
Definition: ah_encrypt.c:326
u32 node_index
Node index.
Definition: node.h:494
#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:338
static void vlib_node_increment_counter(vlib_main_t *vm, u32 node_index, u32 counter_index, u64 increment)
Definition: node_funcs.h:1150
ip46_address_t tunnel_dst_addr
Definition: ipsec_sa.h:157
static u8 * format_ah_encrypt_trace(u8 *s, va_list *args)
Definition: ah_encrypt.c:71
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:169
u16 n_vectors
Definition: node.h:395
vlib_main_t * vm
Definition: buffer.c:312
static char * ah_encrypt_error_strings[]
Definition: ah_encrypt.c:54
#define ARRAY_LEN(x)
Definition: clib.h:62
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:458
vlib_combined_counter_main_t ipsec_sa_counters
SA packet & bytes counters.
Definition: ipsec_sa.c:25
u16 cached_next_index
Next frame index that vector arguments were last enqueued to last time this node ran.
Definition: node.h:513
#define foreach_ah_encrypt_error
Definition: ah_encrypt.c:41
ipsec_sa_t * sad
Definition: ipsec.h:95
dpo_id_t dpo[IPSEC_N_PROTOCOLS]
Definition: ipsec_sa.h:132
static void vlib_buffer_advance(vlib_buffer_t *b, word l)
Advance current data pointer by the supplied (signed!) amount.
Definition: buffer.h:248
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:57
Definition: defs.h:47
index_t dpoi_index
the index of objects of that type
Definition: dpo.h:184
VLIB buffer representation.
Definition: buffer.h:102
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:244
#define vnet_buffer(b)
Definition: buffer.h:369
Definition: ah.h:21
ah_encrypt_error_t
Definition: ah_encrypt.c:46
#define foreach_ah_encrypt_next
Definition: ah_encrypt.c:26
u16 dpoi_next_node
The next VLIB node to follow.
Definition: dpo.h:180
u8 integ_icv_size
Definition: ipsec_sa.h:120
static vlib_buffer_t * vlib_get_buffer(vlib_main_t *vm, u32 buffer_index)
Translate buffer index into buffer pointer.
Definition: buffer_funcs.h:85
static u16 ip4_header_checksum(ip4_header_t *i)
Definition: ip4_packet.h:247