FD.io VPP  v17.01-9-ge7dcee4
Vector Packet Processing
l2t_l2.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 #include <vnet/vnet.h>
16 #include <vnet/ip/ip.h>
17 #include <vnet/ethernet/ethernet.h>
18 
19 #if DPDK == 0
20 #include <vnet/devices/pci/ixgev.h>
21 #include <vnet/devices/pci/ixge.h>
22 #include <vnet/devices/pci/ige.h>
23 #else
24 #include <vnet/devices/dpdk/dpdk.h>
25 #endif
26 
27 #include <vppinfra/error.h>
28 #include <vppinfra/hash.h>
29 #include <app/l2t.h>
30 
32 
33 /* Statistics (not really errors) */
34 #define foreach_l2t_l2_error \
35 _(NETWORK_TO_USER, "L2 network to user (ip6) pkts")
36 
37 static char *l2t_l2_error_strings[] = {
38 #define _(sym,string) string,
40 #undef _
41 };
42 
43 typedef enum
44 {
45 #define _(sym,str) L2T_L2_ERROR_##sym,
47 #undef _
50 
51 /*
52  * Packets go to ethernet-input when they don't match a mapping
53  */
54 typedef enum
55 {
61 
63 
64 #define NSTAGES 3
65 
66 static inline void
67 stage0 (vlib_main_t * vm, vlib_node_runtime_t * node, u32 buffer_index)
68 {
69  vlib_buffer_t *b = vlib_get_buffer (vm, buffer_index);
70  vlib_prefetch_buffer_header (b, STORE);
71  CLIB_PREFETCH (b->data, 2 * CLIB_CACHE_LINE_BYTES, STORE);
72 }
73 
74 static inline void
76 {
77  vlib_buffer_t *b = vlib_get_buffer (vm, bi);
78  l2t_main_t *lm = &l2t_main;
81  u32 session_index;
82  uword *p;
83  uword vlan_and_sw_if_index_key;
84 
85  /* just in case, needed to test with the tun/tap device */
87 
88  eh = vlib_buffer_get_current (b);
89 
90  /* Not a VLAN pkt? send to ethernet-input... */
91  if (PREDICT_FALSE (eh->type != clib_host_to_net_u16 (0x8100)))
92  {
93  vnet_buffer (b)->l2t.next_index = L2T_L2_NEXT_ETHERNET_INPUT;
94  return;
95  }
96  vh = (ethernet_vlan_header_t *) (eh + 1);
97 
98  /* look up session */
99  vlan_and_sw_if_index_key = ((uword) (vh->priority_cfi_and_id) << 32)
100  | vnet_buffer (b)->sw_if_index[VLIB_RX];
101 
102  p = hash_get (lm->session_by_vlan_and_rx_sw_if_index,
103  vlan_and_sw_if_index_key);
104 
105  if (PREDICT_FALSE (p == 0))
106  {
107  /* $$$ drop here if not for our MAC? */
108  vnet_buffer (b)->l2t.next_index = L2T_L2_NEXT_ETHERNET_INPUT;
109  return;
110  }
111  else
112  {
113  session_index = p[0];
114  }
115 
116  /* Remember mapping index, prefetch the mini counter */
117  vnet_buffer (b)->l2t.next_index = L2T_L2_NEXT_IP6_LOOKUP;
118  vnet_buffer (b)->l2t.session_index = session_index;
119 
120  /* Each mapping has 2 x (pkt, byte) counters, hence the shift */
121  CLIB_PREFETCH (lm->counter_main.mini + (p[0] << 1), CLIB_CACHE_LINE_BYTES,
122  STORE);
123 }
124 
125 static inline u32
127 {
128  vlib_buffer_t *b = vlib_get_buffer (vm, bi);
129  l2t_main_t *lm = &l2t_main;
131  vlib_node_t *n = vlib_get_node (vm, l2t_l2_node.index);
132  u32 node_counter_base_index = n->error_heap_index;
133  vlib_error_main_t *em = &vm->error_main;
134  l2tpv3_header_t *l2t; /* l2 header */
135  ethernet_vlan_header_t *vh; /* 802.1q vlan header */
137  l2t_session_t *s;
138  ip6_header_t *ip6;
139  u16 payload_ethertype;
140  u8 dst_mac_address[6];
141  u8 src_mac_address[6];
142  u16 payload_length;
143  i32 backup;
144 
145  /* Other-than-output pkt? We're done... */
146  if (vnet_buffer (b)->l2t.next_index != L2T_L2_NEXT_IP6_LOOKUP)
147  return vnet_buffer (b)->l2t.next_index;
148 
149  vh = (ethernet_vlan_header_t *) (eh + 1);
150 
151  em->counters[node_counter_base_index + L2T_L2_ERROR_NETWORK_TO_USER] += 1;
152 
153  counter_index =
154  session_index_to_counter_index (vnet_buffer (b)->l2t.session_index,
156 
157  /* per-mapping byte stats include the ethernet header */
158  vlib_increment_combined_counter (&lm->counter_main, counter_index,
159  1 /* packet_increment */ ,
161  sizeof (ethernet_header_t));
162 
163  s = pool_elt_at_index (lm->sessions, vnet_buffer (b)->l2t.session_index);
164 
165  /* Save src/dst MAC addresses */
166 #define _(i) dst_mac_address[i] = eh->dst_address[i];
167  _(0) _(1) _(2) _(3) _(4) _(5);
168 #undef _
169 #define _(i) src_mac_address[i] = eh->src_address[i];
170  _(0) _(1) _(2) _(3) _(4) _(5);
171 #undef _
172 
173  payload_ethertype = vh->type;
174 
175  /* Splice out the 802.1q vlan tag */
176  vlib_buffer_advance (b, 4);
177  eh = vlib_buffer_get_current (b);
178 
179  /* restore src/dst MAC addresses */
180 #define _(i) eh->dst_address[i] = dst_mac_address[i];
181  _(0) _(1) _(2) _(3) _(4) _(5);
182 #undef _
183 #define _(i) eh->src_address[i] = src_mac_address[i];
184  _(0) _(1) _(2) _(3) _(4) _(5);
185 #undef _
186  eh->type = payload_ethertype;
187 
188  /* Paint on an l2tpv3 hdr */
189  backup = sizeof (*l2t);
190 #if 0
191  /* back up 4 bytes less if no l2 sublayer */
192  backup -= s->l2_sublayer_present ? 0 : 4;
193 #endif
194 
195  vlib_buffer_advance (b, -backup);
196  l2t = vlib_buffer_get_current (b);
197 
198  l2t->session_id = s->remote_session_id;
199  l2t->cookie = s->remote_cookie;
200 
201 #if 0
202  if (s->l2_sublayer_present)
203  l2t->l2_specific_sublayer = 0;
204 #endif
205 
206  /* Paint on an ip6 header */
207  vlib_buffer_advance (b, -(sizeof (*ip6)));
208  ip6 = vlib_buffer_get_current (b);
209 
211  clib_host_to_net_u32 (0x6 << 28);
212 
213  /* calculate ip6 payload length */
214  payload_length = vlib_buffer_length_in_chain (vm, b);
215  payload_length -= sizeof (*ip6);
216 
217  ip6->payload_length = clib_host_to_net_u16 (payload_length);
218  ip6->protocol = 0x73; /* l2tpv3 */
219  ip6->hop_limit = 0xff;
220  ip6->src_address.as_u64[0] = s->our_address.as_u64[0];
221  ip6->src_address.as_u64[1] = s->our_address.as_u64[1];
222  ip6->dst_address.as_u64[0] = s->client_address.as_u64[0];
223  ip6->dst_address.as_u64[1] = s->client_address.as_u64[1];
224 
225  return L2T_L2_NEXT_IP6_LOOKUP;
226 }
227 
228 #include <vnet/pipeline.h>
229 
230 static uword
232  vlib_node_runtime_t * node, vlib_frame_t * frame)
233 {
234  return dispatch_pipeline (vm, node, frame);
235 }
236 
237 /* *INDENT-OFF* */
239  .function = l2t_l2_node_fn,
240  .name = "l2t-l2-input",
241  .vector_size = sizeof (u32),
242  .format_trace = format_l2t_trace,
244 
245  .n_errors = ARRAY_LEN(l2t_l2_error_strings),
246  .error_strings = l2t_l2_error_strings,
247 
248  .n_next_nodes = L2T_L2_N_NEXT,
249 
250  /* edit / add dispositions here */
251  .next_nodes = {
252  [L2T_L2_NEXT_IP6_LOOKUP] = "ip6-lookup",
253  [L2T_L2_NEXT_ETHERNET_INPUT] = "ethernet-input",
254  [L2T_L2_NEXT_DROP] = "error-drop",
255  },
256 };
257 /* *INDENT-ON* */
258 
260 
261 /*
262  * fd.io coding-style-patch-verification: ON
263  *
264  * Local Variables:
265  * eval: (c-set-style "gnu")
266  * End:
267  */
static u32 last_stage(vlib_main_t *vm, vlib_node_runtime_t *node, u32 bi)
Definition: l2t_l2.c:126
u32 error_heap_index
Definition: node.h:278
bad routing header type(not 4)") sr_error (NO_MORE_SEGMENTS
u64 as_u64[2]
Definition: ip6_packet.h:51
ip6_address_t our_address
Definition: l2tp.h:28
struct _vlib_node_registration vlib_node_registration_t
static void stage1(vlib_main_t *vm, vlib_node_runtime_t *node, u32 bi)
Definition: l2t_l2.c:75
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:100
ip6_address_t src_address
Definition: ip6_packet.h:337
u64 remote_cookie
Definition: l2tp.h:33
static u32 session_index_to_counter_index(u32 session_index, u32 counter_id)
Definition: l2tp.h:106
l2t_l2_next_t
Definition: l2t_l2.c:54
static char * l2t_l2_error_strings[]
Definition: l2t_l2.c:37
ip6_address_t client_address
Definition: l2tp.h:29
static void stage0(vlib_main_t *vm, vlib_node_runtime_t *node, u32 buffer_index)
Definition: l2t_l2.c:67
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:194
static u32 counter_index(vlib_main_t *vm, vlib_error_t e)
int i32
Definition: types.h:81
vlib_node_registration_t l2t_l2_node
(constructor) VLIB_REGISTER_NODE (l2t_l2_node)
Definition: l2t_l2.c:62
#define foreach_l2t_l2_error
Definition: l2t_l2.c:34
#define hash_get(h, key)
Definition: hash.h:248
#define pool_elt_at_index(p, i)
Returns pointer to element at given index.
Definition: pool.h:369
vlib_error_main_t error_main
Definition: main.h:124
u8 * format_l2t_trace(u8 *s, va_list *args)
Definition: l2tp.c:30
#define PREDICT_FALSE(x)
Definition: clib.h:97
static void vlib_buffer_reset(vlib_buffer_t *b)
Reset current header & length to state they were in when packet was received.
Definition: buffer.h:221
u64 * counters
Definition: error.h:78
l2t_l2_error_t
Definition: l2t_l2.c:43
#define CLIB_PREFETCH(addr, size, type)
Definition: cache.h:82
static void vlib_buffer_advance(vlib_buffer_t *b, word l)
Advance current data pointer by the supplied (signed!) amount.
Definition: buffer.h:207
#define ARRAY_LEN(x)
Definition: clib.h:59
static void vlib_increment_combined_counter(vlib_combined_counter_main_t *cm, u32 cpu_index, u32 index, u32 packet_increment, u32 byte_increment)
Increment a combined counter.
Definition: counter.h:241
u32 remote_session_id
Definition: l2tp.h:35
unsigned int u32
Definition: types.h:88
#define vnet_buffer(b)
Definition: buffer.h:361
vlib_combined_counter_main_t counter_main
Definition: l2tp.h:71
u64 uword
Definition: types.h:112
u32 ip_version_traffic_class_and_flow_label
Definition: ip6_packet.h:324
unsigned short u16
Definition: types.h:57
u16 payload_length
Definition: ip6_packet.h:328
unsigned char u8
Definition: types.h:56
static uword l2t_l2_node_fn(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
Definition: l2t_l2.c:231
VLIB_NODE_FUNCTION_MULTIARCH(l2t_l2_node, l2t_l2_node_fn)
l2t_session_t * sessions
Definition: l2tp.h:61
#define vlib_prefetch_buffer_header(b, type)
Prefetch buffer metadata.
Definition: buffer.h:170
#define VLIB_REGISTER_NODE(x,...)
Definition: node.h:143
u8 data[0]
Packet data.
Definition: buffer.h:158
static vlib_node_t * vlib_get_node(vlib_main_t *vm, u32 i)
Get vlib node by index.
Definition: node_funcs.h:58
u8 l2_sublayer_present
Definition: l2tp.h:45
#define CLIB_CACHE_LINE_BYTES
Definition: cache.h:67
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
l2t_main_t l2t_main
Definition: l2t_l2.c:31
Definition: defs.h:46
ip6_address_t dst_address
Definition: ip6_packet.h:337