FD.io VPP  v19.08-27-gf4dcae4
Vector Packet Processing
node.c
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1 /*
2  * Copyright (c) 2015 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  * llc_node.c: llc packet processing
17  *
18  * Copyright (c) 2010 Eliot Dresselhaus
19  *
20  * Permission is hereby granted, free of charge, to any person obtaining
21  * a copy of this software and associated documentation files (the
22  * "Software"), to deal in the Software without restriction, including
23  * without limitation the rights to use, copy, modify, merge, publish,
24  * distribute, sublicense, and/or sell copies of the Software, and to
25  * permit persons to whom the Software is furnished to do so, subject to
26  * the following conditions:
27  *
28  * The above copyright notice and this permission notice shall be
29  * included in all copies or substantial portions of the Software.
30  *
31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
38  */
39 
40 #include <vlib/vlib.h>
41 #include <vnet/pg/pg.h>
42 #include <vnet/llc/llc.h>
43 
44 #define foreach_llc_input_next \
45  _ (PUNT, "error-punt") \
46  _ (DROP, "error-drop")
47 
48 typedef enum
49 {
50 #define _(s,n) LLC_INPUT_NEXT_##s,
52 #undef _
55 
56 typedef struct
57 {
58  u8 packet_data[32];
60 
61 static u8 *
62 format_llc_input_trace (u8 * s, va_list * va)
63 {
64  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
65  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
66  llc_input_trace_t *t = va_arg (*va, llc_input_trace_t *);
67 
68  s = format (s, "%U", format_llc_header, t->packet_data);
69 
70  return s;
71 }
72 
73 static uword
75  vlib_node_runtime_t * node, vlib_frame_t * from_frame)
76 {
77  llc_main_t *lm = &llc_main;
78  u32 n_left_from, next_index, *from, *to_next;
79 
80  from = vlib_frame_vector_args (from_frame);
81  n_left_from = from_frame->n_vectors;
82 
83  if (node->flags & VLIB_NODE_FLAG_TRACE)
85  from,
86  n_left_from,
87  sizeof (from[0]),
88  sizeof (llc_input_trace_t));
89 
90  next_index = node->cached_next_index;
91 
92  while (n_left_from > 0)
93  {
94  u32 n_left_to_next;
95 
96  vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
97 
98  while (n_left_from >= 4 && n_left_to_next >= 2)
99  {
100  u32 bi0, bi1;
101  vlib_buffer_t *b0, *b1;
102  llc_header_t *h0, *h1;
103  u8 next0, next1, len0, len1, enqueue_code;
104 
105  /* Prefetch next iteration. */
106  {
107  vlib_buffer_t *b2, *b3;
108 
109  b2 = vlib_get_buffer (vm, from[2]);
110  b3 = vlib_get_buffer (vm, from[3]);
111 
112  vlib_prefetch_buffer_header (b2, LOAD);
113  vlib_prefetch_buffer_header (b3, LOAD);
114 
115  CLIB_PREFETCH (b2->data, sizeof (h0[0]), LOAD);
116  CLIB_PREFETCH (b3->data, sizeof (h1[0]), LOAD);
117  }
118 
119  bi0 = from[0];
120  bi1 = from[1];
121  to_next[0] = bi0;
122  to_next[1] = bi1;
123  from += 2;
124  to_next += 2;
125  n_left_to_next -= 2;
126  n_left_from -= 2;
127 
128  b0 = vlib_get_buffer (vm, bi0);
129  b1 = vlib_get_buffer (vm, bi1);
130 
131  h0 = vlib_buffer_get_current (b0);
132  h1 = vlib_buffer_get_current (b1);
133 
134  len0 = llc_header_length (h0);
135  len1 = llc_header_length (h1);
136 
137  vlib_buffer_advance (b0, len0);
138  vlib_buffer_advance (b1, len1);
139 
140  next0 = lm->input_next_by_protocol[h0->dst_sap];
141  next1 = lm->input_next_by_protocol[h1->dst_sap];
142 
143  b0->error =
144  node->errors[next0 ==
145  LLC_INPUT_NEXT_DROP ? LLC_ERROR_UNKNOWN_PROTOCOL :
146  LLC_ERROR_NONE];
147  b1->error =
148  node->errors[next1 ==
149  LLC_INPUT_NEXT_DROP ? LLC_ERROR_UNKNOWN_PROTOCOL :
150  LLC_ERROR_NONE];
151 
152  enqueue_code = (next0 != next_index) + 2 * (next1 != next_index);
153 
154  if (PREDICT_FALSE (enqueue_code != 0))
155  {
156  switch (enqueue_code)
157  {
158  case 1:
159  /* A B A */
160  to_next[-2] = bi1;
161  to_next -= 1;
162  n_left_to_next += 1;
163  vlib_set_next_frame_buffer (vm, node, next0, bi0);
164  break;
165 
166  case 2:
167  /* A A B */
168  to_next -= 1;
169  n_left_to_next += 1;
170  vlib_set_next_frame_buffer (vm, node, next1, bi1);
171  break;
172 
173  case 3:
174  /* A B B or A B C */
175  to_next -= 2;
176  n_left_to_next += 2;
177  vlib_set_next_frame_buffer (vm, node, next0, bi0);
178  vlib_set_next_frame_buffer (vm, node, next1, bi1);
179  if (next0 == next1)
180  {
181  vlib_put_next_frame (vm, node, next_index,
182  n_left_to_next);
183  next_index = next1;
184  vlib_get_next_frame (vm, node, next_index, to_next,
185  n_left_to_next);
186  }
187  }
188  }
189  }
190 
191  while (n_left_from > 0 && n_left_to_next > 0)
192  {
193  u32 bi0;
194  vlib_buffer_t *b0;
195  llc_header_t *h0;
196  u8 next0, len0;
197 
198  bi0 = from[0];
199  to_next[0] = bi0;
200  from += 1;
201  to_next += 1;
202  n_left_from -= 1;
203  n_left_to_next -= 1;
204 
205  b0 = vlib_get_buffer (vm, bi0);
206 
207  h0 = vlib_buffer_get_current (b0);
208 
209  len0 = llc_header_length (h0);
210 
211  vlib_buffer_advance (b0, len0);
212 
213  next0 = lm->input_next_by_protocol[h0->dst_sap];
214 
215  b0->error =
216  node->errors[next0 ==
217  LLC_INPUT_NEXT_DROP ? LLC_ERROR_UNKNOWN_PROTOCOL :
218  LLC_ERROR_NONE];
219 
220  /* Sent packet to wrong next? */
221  if (PREDICT_FALSE (next0 != next_index))
222  {
223  /* Return old frame; remove incorrectly enqueued packet. */
224  vlib_put_next_frame (vm, node, next_index, n_left_to_next + 1);
225 
226  /* Send to correct next. */
227  next_index = next0;
228  vlib_get_next_frame (vm, node, next_index,
229  to_next, n_left_to_next);
230 
231  to_next[0] = bi0;
232  to_next += 1;
233  n_left_to_next -= 1;
234  }
235  }
236 
237  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
238  }
239 
240  return from_frame->n_vectors;
241 }
242 
243 static char *llc_error_strings[] = {
244 #define _(f,s) s,
246 #undef _
247 };
248 
249 /* *INDENT-OFF* */
251  .function = llc_input,
252  .name = "llc-input",
253  /* Takes a vector of packets. */
254  .vector_size = sizeof (u32),
255 
256  .n_errors = LLC_N_ERROR,
257  .error_strings = llc_error_strings,
258 
259  .n_next_nodes = LLC_INPUT_N_NEXT,
260  .next_nodes = {
261 #define _(s,n) [LLC_INPUT_NEXT_##s] = n,
263 #undef _
264  },
265 
266  .format_buffer = format_llc_header_with_length,
267  .format_trace = format_llc_input_trace,
268  .unformat_buffer = unformat_llc_header,
269 };
270 /* *INDENT-ON* */
271 
272 static clib_error_t *
274 {
275  llc_main_t *lm = &llc_main;
276 
277  {
279  if (error)
280  clib_error_report (error);
281  }
282 
283  llc_setup_node (vm, llc_input_node.index);
284 
285  {
286  int i;
287  for (i = 0; i < ARRAY_LEN (lm->input_next_by_protocol); i++)
288  lm->input_next_by_protocol[i] = LLC_INPUT_NEXT_DROP;
289  }
290 
291  return 0;
292 }
293 
295 
296 void
298  llc_protocol_t protocol, u32 node_index)
299 {
300  llc_main_t *lm = &llc_main;
302 
303  {
305  if (error)
306  clib_error_report (error);
307  /* Otherwise, osi_input_init will wipe out e.g. the snap init */
309  if (error)
310  clib_error_report (error);
311  }
312 
313  pi = llc_get_protocol_info (lm, protocol);
314  pi->node_index = node_index;
315  pi->next_index = vlib_node_add_next (vm, llc_input_node.index, node_index);
316 
318 }
319 
320 /*
321  * fd.io coding-style-patch-verification: ON
322  *
323  * Local Variables:
324  * eval: (c-set-style "gnu")
325  * End:
326  */
#define CLIB_UNUSED(x)
Definition: clib.h:82
static u8 llc_header_length(llc_header_t *h)
Definition: llc.h:101
static void vlib_set_next_frame_buffer(vlib_main_t *vm, vlib_node_runtime_t *node, u32 next_index, u32 buffer_index)
Definition: node_funcs.h:371
u8 data[0]
Packet data.
Definition: buffer.h:181
int i
void llc_register_input_protocol(vlib_main_t *vm, llc_protocol_t protocol, u32 node_index)
Definition: node.c:297
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:424
vlib_error_t * errors
Vector of errors for this node.
Definition: node.h:468
static uword vlib_node_add_next(vlib_main_t *vm, uword node, uword next_node)
Definition: node_funcs.h:1092
unsigned char u8
Definition: types.h:56
static u8 * format_llc_input_trace(u8 *s, va_list *va)
Definition: node.c:62
llc_input_next_t
Definition: node.c:48
#define foreach_llc_input_next
Definition: node.c:44
#define VLIB_INIT_FUNCTION(x)
Definition: init.h:173
#define vlib_prefetch_buffer_header(b, type)
Prefetch buffer metadata.
Definition: buffer.h:203
llc_protocol_t
Definition: llc.h:71
unsigned int u32
Definition: types.h:88
#define vlib_call_init_function(vm, x)
Definition: init.h:270
static void llc_setup_node(vlib_main_t *vm, u32 node_index)
Definition: llc.h:173
vlib_error_t error
Error code for buffers to be enqueued to error handler.
Definition: buffer.h:136
vlib_node_registration_t llc_input_node
(constructor) VLIB_REGISTER_NODE (llc_input_node)
Definition: node.c:250
vl_api_ip_proto_t protocol
Definition: punt.api:39
static clib_error_t * osi_input_init(vlib_main_t *vm)
Definition: node.c:266
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:229
unformat_function_t unformat_llc_header
Definition: llc.h:169
#define PREDICT_FALSE(x)
Definition: clib.h:111
format_function_t format_llc_header
Definition: llc.h:162
#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 uword llc_input(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *from_frame)
Definition: node.c:74
static llc_protocol_info_t * llc_get_protocol_info(llc_main_t *m, llc_protocol_t protocol)
Definition: llc.h:148
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:169
u16 n_vectors
Definition: node.h:395
u8 packet_data[32]
Definition: node.c:58
#define CLIB_PREFETCH(addr, size, type)
Definition: cache.h:80
vlib_main_t * vm
Definition: buffer.c:312
#define foreach_llc_error
Definition: llc.h:121
#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
format_function_t format_llc_header_with_length
Definition: llc.h:163
u16 cached_next_index
Next frame index that vector arguments were last enqueued to last time this node ran.
Definition: node.h:513
static char * llc_error_strings[]
Definition: node.c:243
#define clib_error_report(e)
Definition: error.h:113
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 clib_error_t * llc_init(vlib_main_t *vm)
Definition: llc.c:211
void vlib_trace_frame_buffers_only(vlib_main_t *vm, vlib_node_runtime_t *node, u32 *buffers, uword n_buffers, uword next_buffer_stride, uword n_buffer_data_bytes_in_trace)
Definition: trace.c:47
u8 input_next_by_protocol[256]
Definition: llc.h:144
llc_main_t llc_main
Definition: llc.c:44
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
u16 flags
Copy of main node flags.
Definition: node.h:507
#define VLIB_NODE_FLAG_TRACE
Definition: node.h:301
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
u8 dst_sap
Definition: llc.h:82
static clib_error_t * llc_input_init(vlib_main_t *vm)
Definition: node.c:273