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Vector Packet Processing
adj_l2.c
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1 /*
2  * Copyright (c) 2016 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 #include <vnet/vnet.h>
17 #include <vnet/adj/adj_l2.h>
18 #include <vnet/ethernet/ethernet.h>
19 #include <vnet/ip/ip.h>
20 
21 /**
22  * @brief Trace data for a L2 Midchain
23  */
24 typedef struct adj_l2_trace_t_ {
25  /** Adjacency index taken. */
28 
29 static u8 *
30 format_adj_l2_trace (u8 * s, va_list * args)
31 {
32  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
33  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
34  adj_l2_trace_t * t = va_arg (*args, adj_l2_trace_t *);
35 
36  s = format (s, "adj-idx %d : %U",
37  t->adj_index,
39  return s;
40 }
41 
43 {
46 
51  int is_midchain,
52  int do_counters)
53 {
54  u32 * from = vlib_frame_vector_args (frame);
55  u32 n_left_from, n_left_to_next, * to_next, next_index;
56  u32 thread_index = vlib_get_thread_index();
58 
59  n_left_from = frame->n_vectors;
60  next_index = node->cached_next_index;
61 
62  while (n_left_from > 0)
63  {
64  vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
65 
66  while (n_left_from > 0 && n_left_to_next > 0)
67  {
68  ip_adjacency_t * adj0;
69  vlib_buffer_t * p0;
70  char *h0;
71  u32 pi0, rw_len0, len0, adj_index0, next0 = 0;
72  u32 tx_sw_if_index0;
73 
74  pi0 = to_next[0] = from[0];
75  from += 1;
76  n_left_from -= 1;
77  to_next += 1;
78  n_left_to_next -= 1;
79 
80  p0 = vlib_get_buffer (vm, pi0);
81  h0 = vlib_buffer_get_current (p0);
82 
83  adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
84 
85  adj0 = adj_get (adj_index0);
86 
87  /* Guess we are writing on ip4 header. */
88  vnet_rewrite_one_header (adj0[0], h0,
89  //sizeof (gre_header_t) +
90  sizeof (ip4_header_t));
91 
92  /* Update packet buffer attributes/set output interface. */
93  rw_len0 = adj0[0].rewrite_header.data_bytes;
94  vnet_buffer(p0)->ip.save_rewrite_length = rw_len0;
95  vnet_buffer(p0)->sw_if_index[VLIB_TX] = adj0->rewrite_header.sw_if_index;
96  len0 = vlib_buffer_length_in_chain (vm, p0);
97  /* since we are coming out of the L2 world, where the vlib_buffer
98  * union is used for other things, make sure it is clean for
99  * MPLS from now on.
100  */
101  vnet_buffer(p0)->mpls.first = 0;
102 
103  if (do_counters)
105  thread_index,
106  adj_index0,
107  0, len0);
108 
109  /* Check MTU of outgoing interface. */
110  if (PREDICT_TRUE(len0 <= adj0[0].rewrite_header.max_l3_packet_bytes))
111  {
112  /* Don't adjust the buffer for ttl issue; icmp-error node wants
113  * to see the IP header */
114  p0->current_data -= rw_len0;
115  p0->current_length += rw_len0;
116  tx_sw_if_index0 = adj0[0].rewrite_header.sw_if_index;
117 
118  if (is_midchain)
119  {
120  adj0->sub_type.midchain.fixup_func(
121  vm, adj0, p0,
122  adj0->sub_type.midchain.fixup_data);
123  }
124 
125  vnet_buffer (p0)->sw_if_index[VLIB_TX] = tx_sw_if_index0;
126 
127  /*
128  * Follow the feature ARC. this will result eventually in
129  * the midchain-tx node
130  */
131  if (PREDICT_FALSE (adj0->rewrite_header.flags &
135  tx_sw_if_index0,
136  &next0, p0,
137  adj0->ia_cfg_index);
138  else
139  next0 = adj0[0].rewrite_header.next_index;
140  }
141  else
142  {
143  /* can't fragment L2 */
144  next0 = ADJ_L2_REWRITE_NEXT_DROP;
145  }
146 
147  if (PREDICT_FALSE(p0->flags & VLIB_BUFFER_IS_TRACED))
148  {
149  adj_l2_trace_t *tr = vlib_add_trace (vm, node,
150  p0, sizeof (*tr));
151  tr->adj_index = vnet_buffer(p0)->ip.adj_index[VLIB_TX];
152  }
153 
154  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
155  to_next, n_left_to_next,
156  pi0, next0);
157  }
158 
159  vlib_put_next_frame (vm, node, next_index, n_left_to_next);
160  }
161 
162  return frame->n_vectors;
163 }
164 
168 {
170  return adj_l2_rewrite_inline (vm, node, frame, 0, 1);
171  else
172  return adj_l2_rewrite_inline (vm, node, frame, 0, 0);
173 }
174 
178 {
180  return adj_l2_rewrite_inline (vm, node, frame, 1, 1);
181  else
182  return adj_l2_rewrite_inline (vm, node, frame, 1, 0);
183 }
184 
186  .name = "adj-l2-rewrite",
187  .vector_size = sizeof (u32),
188 
189  .format_trace = format_adj_l2_trace,
190 
191  .n_next_nodes = 1,
192  .next_nodes = {
193  [ADJ_L2_REWRITE_NEXT_DROP] = "error-drop",
194  },
195 };
196 
198  .name = "adj-l2-midchain",
199  .vector_size = sizeof (u32),
200 
201  .format_trace = format_adj_l2_trace,
202 
203  .n_next_nodes = 1,
204  .next_nodes = {
205  [ADJ_L2_REWRITE_NEXT_DROP] = "error-drop",
206  },
207 };
#define vnet_rewrite_one_header(rw0, p0, most_likely_size)
Definition: rewrite.h:211
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
#define CLIB_UNUSED(x)
Definition: clib.h:86
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:119
i16 current_data
signed offset in data[], pre_data[] that we are currently processing.
Definition: buffer.h:110
IP unicast adjacency.
Definition: adj.h:227
u16 current_length
Nbytes between current data and the end of this buffer.
Definition: buffer.h:113
union ip_adjacency_t_::@137 sub_type
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:424
#define VLIB_NODE_FN(node)
Definition: node.h:202
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:402
unsigned char u8
Definition: types.h:56
ethernet_main_t ethernet_main
Definition: init.c:45
static ip_adjacency_t * adj_get(adj_index_t adj_index)
Get a pointer to an adjacency object from its index.
Definition: adj.h:459
format_function_t format_ip_adjacency
Definition: format.h:58
struct ip_adjacency_t_::@137::@139 midchain
IP_LOOKUP_NEXT_MIDCHAIN.
unsigned int u32
Definition: types.h:88
vlib_node_registration_t adj_l2_midchain_node
(constructor) VLIB_REGISTER_NODE (adj_l2_midchain_node)
Definition: adj_l2.c:197
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:229
static_always_inline void * vnet_feature_arc_start_w_cfg_index(u8 arc, u32 sw_if_index, u32 *next, vlib_buffer_t *b, u32 cfg_index)
Definition: feature.h:285
#define PREDICT_FALSE(x)
Definition: clib.h:118
#define always_inline
Definition: ipsec.h:28
static u8 * format_adj_l2_trace(u8 *s, va_list *args)
Definition: adj_l2.c:30
#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:224
#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
adj_l2_rewrite_next_t_
Definition: adj_l2.c:42
vlib_main_t * vm
Definition: in2out_ed.c:1599
vlib_combined_counter_main_t adjacency_counters
Adjacency packet counters.
Definition: adj.c:25
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:169
u16 n_vectors
Definition: node.h:399
static_always_inline uword vlib_get_thread_index(void)
Definition: threads.h:218
struct adj_l2_trace_t_ adj_l2_trace_t
Trace data for a L2 Midchain.
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:483
vlib_main_t vlib_node_runtime_t * node
Definition: in2out_ed.c:1599
u16 cached_next_index
Next frame index that vector arguments were last enqueued to last time this node ran.
Definition: node.h:517
u32 ia_cfg_index
feature [arc] config index
Definition: adj.h:239
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
Definition: defs.h:47
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
Trace data for a L2 Midchain.
Definition: adj_l2.c:24
#define vnet_buffer(b)
Definition: buffer.h:417
u32 adj_index
Adjacency index taken.
Definition: adj_l2.c:26
vlib_node_registration_t adj_l2_rewrite_node
(constructor) VLIB_REGISTER_NODE (adj_l2_rewrite_node)
Definition: adj_l2.c:185
static uword adj_l2_rewrite_inline(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame, int is_midchain, int do_counters)
Definition: adj_l2.c:48
vlib_main_t vlib_node_runtime_t vlib_frame_t * frame
Definition: in2out_ed.c:1600
This adjacency/interface has output features configured.
Definition: rewrite.h:57
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
enum adj_l2_rewrite_next_t_ adj_l2_rewrite_next_t
u8 output_feature_arc_index
Definition: ethernet.h:317
static int adj_are_counters_enabled(void)
Get the global configuration option for enabling per-adj counters.
Definition: adj.h:474