FD.io VPP  v18.04-17-g3a0d853
Vector Packet Processing
udp.h
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1 /*
2  * Copyright (c) 2017 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 #ifndef __included_udp_h__
16 #define __included_udp_h__
17 
18 #include <vnet/vnet.h>
19 #include <vnet/udp/udp_packet.h>
20 #include <vnet/ip/ip.h>
21 #include <vnet/ip/ip4.h>
22 #include <vnet/ip/ip4_packet.h>
23 #include <vnet/pg/pg.h>
24 #include <vnet/ip/format.h>
25 
26 #include <vnet/ip/ip.h>
27 #include <vnet/session/transport.h>
28 
29 typedef enum
30 {
31 #define udp_error(n,s) UDP_ERROR_##n,
32 #include <vnet/udp/udp_error.def>
33 #undef udp_error
35 } udp_error_t;
36 
37 typedef struct
38 {
39  /** Required for pool_get_aligned */
40  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
41  transport_connection_t connection; /** must be first */
42  /** ersatz MTU to limit fifo pushes to test data size */
45 
46 #define foreach_udp4_dst_port \
47 _ (53, dns) \
48 _ (67, dhcp_to_server) \
49 _ (68, dhcp_to_client) \
50 _ (500, ikev2) \
51 _ (2152, GTPU) \
52 _ (3784, bfd4) \
53 _ (3785, bfd_echo4) \
54 _ (4341, lisp_gpe) \
55 _ (4342, lisp_cp) \
56 _ (4739, ipfix) \
57 _ (4789, vxlan) \
58 _ (4789, vxlan6) \
59 _ (4790, VXLAN_GPE) \
60 _ (6633, vpath_3) \
61 _ (6081, geneve) \
62 _ (53053, dns_reply)
63 
64 
65 #define foreach_udp6_dst_port \
66 _ (53, dns6) \
67 _ (547, dhcpv6_to_server) \
68 _ (546, dhcpv6_to_client) \
69 _ (2152, GTPU6) \
70 _ (3784, bfd6) \
71 _ (3785, bfd_echo6) \
72 _ (4341, lisp_gpe6) \
73 _ (4342, lisp_cp6) \
74 _ (4790, VXLAN6_GPE) \
75 _ (6633, vpath6_3) \
76 _ (6081, geneve6) \
77 _ (8138, BIER) \
78 _ (53053, dns_reply6)
79 
80 typedef enum
81 {
82 #define _(n,f) UDP_DST_PORT_##f = n,
84 #undef _
86 
87 typedef enum
88 {
89 #define _(n,f) UDP6_DST_PORT_##f = n,
91 #undef _
93 
94 typedef struct
95 {
96  /* Name (a c string). */
97  char *name;
98 
99  /* GRE protocol type in host byte order. */
101 
102  /* Node which handles this type. */
104 
105  /* Next index for this type. */
108 
109 typedef enum
110 {
111  UDP_IP6 = 0,
112  UDP_IP4, /* the code is full of is_ip4... */
114 } udp_af_t;
115 
116 typedef struct
117 {
118  udp_dst_port_info_t *dst_port_infos[N_UDP_AF];
119 
120  /* Hash tables mapping name/protocol to protocol info index. */
121  uword *dst_port_info_by_name[N_UDP_AF];
122  uword *dst_port_info_by_dst_port[N_UDP_AF];
123 
124  /* Sparse vector mapping udp dst_port in network byte order
125  to next index. */
130 
131  /*
132  * Per-worker thread udp connection pools used with session layer
133  */
139 
140 } udp_main_t;
141 
142 extern udp_main_t udp_main;
145 
147 udp_connection_get (u32 conn_index, u32 thread_index)
148 {
149  if (pool_is_free_index (udp_main.connections[thread_index], conn_index))
150  return 0;
151  return pool_elt_at_index (udp_main.connections[thread_index], conn_index);
152 }
153 
155 udp_listener_get (u32 conn_index)
156 {
157  return pool_elt_at_index (udp_main.listener_pool, conn_index);
158 }
159 
162 {
163  return &udp_main;
164 }
165 
168 {
169  return ((udp_connection_t *) tc);
170 }
171 
174 {
175  return (uc - udp_main.connections[uc->c_thread_index]);
176 }
177 
179 
180 /**
181  * Acquires a lock that blocks a connection pool from expanding.
182  */
183 always_inline void
184 udp_pool_add_peeker (u32 thread_index)
185 {
186  if (thread_index != vlib_get_thread_index ())
187  return;
188  clib_spinlock_lock_if_init (&udp_main.peekers_readers_locks[thread_index]);
189  udp_main.connection_peekers[thread_index] += 1;
190  if (udp_main.connection_peekers[thread_index] == 1)
191  clib_spinlock_lock_if_init (&udp_main.peekers_write_locks[thread_index]);
193  [thread_index]);
194 }
195 
196 always_inline void
198 {
199  if (thread_index != vlib_get_thread_index ())
200  return;
201  ASSERT (udp_main.connection_peekers[thread_index] > 0);
202  clib_spinlock_lock_if_init (&udp_main.peekers_readers_locks[thread_index]);
203  udp_main.connection_peekers[thread_index] -= 1;
204  if (udp_main.connection_peekers[thread_index] == 0)
206  [thread_index]);
208  [thread_index]);
209 }
210 
212 udp_conenction_clone_safe (u32 connection_index, u32 thread_index)
213 {
214  udp_connection_t *old_c, *new_c;
215  u32 current_thread_index = vlib_get_thread_index ();
216  new_c = udp_connection_alloc (current_thread_index);
217 
218  /* If during the memcpy pool is reallocated AND the memory allocator
219  * decides to give the old chunk of memory to somebody in a hurry to
220  * scribble something on it, we have a problem. So add this thread as
221  * a session pool peeker.
222  */
223  udp_pool_add_peeker (thread_index);
224  old_c = udp_main.connections[thread_index] + connection_index;
225  clib_memcpy (new_c, old_c, sizeof (*new_c));
226  udp_pool_remove_peeker (thread_index);
227  new_c->c_thread_index = current_thread_index;
228  new_c->c_c_index = udp_connection_index (new_c);
229  return new_c;
230 }
231 
232 
235 {
236  uword *p = hash_get (um->dst_port_info_by_dst_port[is_ip4], dst_port);
237  return p ? vec_elt_at_index (um->dst_port_infos[is_ip4], p[0]) : 0;
238 }
239 
243 
245  udp_dst_port_t dst_port,
246  u32 node_index, u8 is_ip4);
248  udp_dst_port_t dst_port, u8 is_ip4);
249 
250 void udp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
251 
252 always_inline void *
253 vlib_buffer_push_udp (vlib_buffer_t * b, u16 sp, u16 dp, u8 offload_csum)
254 {
255  udp_header_t *uh;
256 
257  uh = vlib_buffer_push_uninit (b, sizeof (udp_header_t));
258  uh->src_port = sp;
259  uh->dst_port = dp;
260  uh->checksum = 0;
261  uh->length = clib_host_to_net_u16 (b->current_length);
262  if (offload_csum)
263  {
264  b->flags |= VNET_BUFFER_F_OFFLOAD_UDP_CKSUM;
265  vnet_buffer (b)->l4_hdr_offset = (u8 *) uh - b->data;
266  }
267  return uh;
268 }
269 
270 always_inline void
272 {
273  u16 new_l0;
274  udp_header_t *udp0;
275 
276  if (is_ip4)
277  {
278  ip4_header_t *ip0;
279  ip_csum_t sum0;
280  u16 old_l0 = 0;
281 
282  ip0 = vlib_buffer_get_current (b0);
283 
284  /* fix the <bleep>ing outer-IP checksum */
285  sum0 = ip0->checksum;
286  /* old_l0 always 0, see the rewrite setup */
287  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
288 
289  sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
290  length /* changed member */ );
291  ip0->checksum = ip_csum_fold (sum0);
292  ip0->length = new_l0;
293 
294  /* Fix UDP length */
295  udp0 = (udp_header_t *) (ip0 + 1);
296  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
297  - sizeof (*ip0));
298  udp0->length = new_l0;
299  }
300  else
301  {
302  ip6_header_t *ip0;
303  int bogus0;
304 
305  ip0 = vlib_buffer_get_current (b0);
306 
307  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
308  - sizeof (*ip0));
309  ip0->payload_length = new_l0;
310 
311  /* Fix UDP length */
312  udp0 = (udp_header_t *) (ip0 + 1);
313  udp0->length = new_l0;
314 
315  udp0->checksum =
316  ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
317  ASSERT (bogus0 == 0);
318 
319  if (udp0->checksum == 0)
320  udp0->checksum = 0xffff;
321  }
322 }
323 
324 always_inline void
326  u8 is_ip4)
327 {
328  vlib_buffer_advance (b0, -ec_len);
329 
330  if (is_ip4)
331  {
332  ip4_header_t *ip0;
333 
334  ip0 = vlib_buffer_get_current (b0);
335 
336  /* Apply the encap string. */
337  clib_memcpy (ip0, ec0, ec_len);
338  ip_udp_fixup_one (vm, b0, 1);
339  }
340  else
341  {
342  ip6_header_t *ip0;
343 
344  ip0 = vlib_buffer_get_current (b0);
345 
346  /* Apply the encap string. */
347  clib_memcpy (ip0, ec0, ec_len);
348  ip_udp_fixup_one (vm, b0, 0);
349  }
350 }
351 
352 always_inline void
354  u8 * ec0, u8 * ec1, word ec_len, u8 is_v4)
355 {
356  u16 new_l0, new_l1;
357  udp_header_t *udp0, *udp1;
358 
359  ASSERT (_vec_len (ec0) == _vec_len (ec1));
360 
361  vlib_buffer_advance (b0, -ec_len);
362  vlib_buffer_advance (b1, -ec_len);
363 
364  if (is_v4)
365  {
366  ip4_header_t *ip0, *ip1;
367  ip_csum_t sum0, sum1;
368  u16 old_l0 = 0, old_l1 = 0;
369 
370  ip0 = vlib_buffer_get_current (b0);
371  ip1 = vlib_buffer_get_current (b1);
372 
373  /* Apply the encap string */
374  clib_memcpy (ip0, ec0, ec_len);
375  clib_memcpy (ip1, ec1, ec_len);
376 
377  /* fix the <bleep>ing outer-IP checksum */
378  sum0 = ip0->checksum;
379  sum1 = ip1->checksum;
380 
381  /* old_l0 always 0, see the rewrite setup */
382  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
383  new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1));
384 
385  sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
386  length /* changed member */ );
387  sum1 = ip_csum_update (sum1, old_l1, new_l1, ip4_header_t,
388  length /* changed member */ );
389 
390  ip0->checksum = ip_csum_fold (sum0);
391  ip1->checksum = ip_csum_fold (sum1);
392 
393  ip0->length = new_l0;
394  ip1->length = new_l1;
395 
396  /* Fix UDP length */
397  udp0 = (udp_header_t *) (ip0 + 1);
398  udp1 = (udp_header_t *) (ip1 + 1);
399 
400  new_l0 =
401  clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
402  sizeof (*ip0));
403  new_l1 =
404  clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1) -
405  sizeof (*ip1));
406  udp0->length = new_l0;
407  udp1->length = new_l1;
408  }
409  else
410  {
411  ip6_header_t *ip0, *ip1;
412  int bogus0, bogus1;
413 
414  ip0 = vlib_buffer_get_current (b0);
415  ip1 = vlib_buffer_get_current (b1);
416 
417  /* Apply the encap string. */
418  clib_memcpy (ip0, ec0, ec_len);
419  clib_memcpy (ip1, ec1, ec_len);
420 
421  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
422  - sizeof (*ip0));
423  new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1)
424  - sizeof (*ip1));
425  ip0->payload_length = new_l0;
426  ip1->payload_length = new_l1;
427 
428  /* Fix UDP length */
429  udp0 = (udp_header_t *) (ip0 + 1);
430  udp1 = (udp_header_t *) (ip1 + 1);
431 
432  udp0->length = new_l0;
433  udp1->length = new_l1;
434 
435  udp0->checksum =
436  ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
437  udp1->checksum =
438  ip6_tcp_udp_icmp_compute_checksum (vm, b1, ip1, &bogus1);
439  ASSERT (bogus0 == 0);
440  ASSERT (bogus1 == 0);
441 
442  if (udp0->checksum == 0)
443  udp0->checksum = 0xffff;
444  if (udp1->checksum == 0)
445  udp1->checksum = 0xffff;
446  }
447 }
448 
449 /*
450  * fd.io coding-style-patch-verification: ON
451  *
452  * Local Variables:
453  * eval: (c-set-style "gnu")
454  * End:
455  */
456 
457 #endif /* __included_udp_h__ */
uword( unformat_function_t)(unformat_input_t *input, va_list *args)
Definition: format.h:231
static udp_connection_t * udp_listener_get(u32 conn_index)
Definition: udp.h:155
#define CLIB_CACHE_LINE_ALIGN_MARK(mark)
Definition: cache.h:60
u16 * next_by_dst_port6
Definition: udp.h:127
unformat_function_t unformat_udp_header
Definition: udp.h:242
struct _transport_connection transport_connection_t
u32 * connection_peekers
Definition: udp.h:135
uword * dst_port_info_by_dst_port[N_UDP_AF]
Definition: udp.h:122
static udp_connection_t * udp_get_connection_from_transport(transport_connection_t *tc)
Definition: udp.h:167
static_always_inline void clib_spinlock_unlock_if_init(clib_spinlock_t *p)
Definition: lock.h:98
static udp_dst_port_info_t * udp_get_dst_port_info(udp_main_t *um, udp_dst_port_t dst_port, u8 is_ip4)
Definition: udp.h:234
uword ip_csum_t
Definition: ip_packet.h:90
u8 *( format_function_t)(u8 *s, va_list *args)
Definition: format.h:48
u8 punt_unknown6
Definition: udp.h:129
static void * vlib_buffer_push_udp(vlib_buffer_t *b, u16 sp, u16 dp, u8 offload_csum)
Definition: udp.h:253
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:107
static udp_main_t * vnet_get_udp_main()
Definition: udp.h:161
#define always_inline
Definition: clib.h:92
udp_connection_t * udp_connection_alloc(u32 thread_index)
Definition: udp.c:26
u8 punt_unknown4
Definition: udp.h:128
#define vec_elt_at_index(v, i)
Get vector value at index i checking that i is in bounds.
#define foreach_udp6_dst_port
Definition: udp.h:65
static void udp_pool_remove_peeker(u32 thread_index)
Definition: udp.h:197
vlib_node_registration_t udp4_input_node
(constructor) VLIB_REGISTER_NODE (udp4_input_node)
Definition: udp_input.c:257
#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:461
u16 * next_by_dst_port4
Definition: udp.h:126
udp_main_t udp_main
Definition: udp_local.c:24
u16 current_length
Nbytes between current data and the end of this buffer.
Definition: buffer.h:108
static u32 udp_connection_index(udp_connection_t *uc)
Definition: udp.h:173
udp_dst_port_info_t * dst_port_infos[N_UDP_AF]
Definition: udp.h:118
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:209
clib_spinlock_t * peekers_readers_locks
Definition: udp.h:136
vlib_node_registration_t udp6_input_node
(constructor) VLIB_REGISTER_NODE (udp6_input_node)
Definition: udp_input.c:283
udp_connection_t * listener_pool
Definition: udp.h:138
static void ip_udp_encap_one(vlib_main_t *vm, vlib_buffer_t *b0, u8 *ec0, word ec_len, u8 is_ip4)
Definition: udp.h:325
Definition: udp.h:111
static void udp_pool_add_peeker(u32 thread_index)
Acquires a lock that blocks a connection pool from expanding.
Definition: udp.h:184
void udp_punt_unknown(vlib_main_t *vm, u8 is_ip4, u8 is_add)
Definition: udp_local.c:553
static void ip_udp_fixup_one(vlib_main_t *vm, vlib_buffer_t *b0, u8 is_ip4)
Definition: udp.h:271
format_function_t format_udp_rx_trace
Definition: udp.h:241
static void ip_udp_encap_two(vlib_main_t *vm, vlib_buffer_t *b0, vlib_buffer_t *b1, u8 *ec0, u8 *ec1, word ec_len, u8 is_v4)
Definition: udp.h:353
static_always_inline uword vlib_get_thread_index(void)
Definition: threads.h:221
vlib_main_t * vm
Definition: buffer.c:294
void udp_unregister_dst_port(vlib_main_t *vm, udp_dst_port_t dst_port, u8 is_ip4)
Definition: udp_local.c:530
#define clib_memcpy(a, b, c)
Definition: string.h:75
static udp_connection_t * udp_connection_get(u32 conn_index, u32 thread_index)
Definition: udp.h:147
udp_error_t
Definition: udp.h:29
#define pool_is_free_index(P, I)
Use free bitmap to query whether given index is free.
Definition: pool.h:270
udp_dst_port_t
Definition: udp.h:80
u16 ip6_tcp_udp_icmp_compute_checksum(vlib_main_t *vm, vlib_buffer_t *p0, ip6_header_t *ip0, int *bogus_lengthp)
Definition: ip6_forward.c:865
#define foreach_udp4_dst_port
Definition: udp.h:46
#define ASSERT(truth)
unsigned int u32
Definition: types.h:88
udp_af_t
Definition: udp.h:109
udp_dst_port_t dst_port
Definition: udp.h:100
char * name
Definition: udp.h:97
static void vlib_buffer_advance(vlib_buffer_t *b, word l)
Advance current data pointer by the supplied (signed!) amount.
Definition: buffer.h:222
static udp_connection_t * udp_conenction_clone_safe(u32 connection_index, u32 thread_index)
Definition: udp.h:212
clib_spinlock_t * peekers_write_locks
Definition: udp.h:137
u64 uword
Definition: types.h:112
struct _vlib_node_registration vlib_node_registration_t
static void * vlib_buffer_push_uninit(vlib_buffer_t *b, u8 size)
Prepend uninitialized data to buffer.
Definition: buffer.h:306
unsigned short u16
Definition: types.h:57
u16 payload_length
Definition: ip6_packet.h:333
i64 word
Definition: types.h:111
transport_connection_t connection
Definition: udp.h:41
unsigned char u8
Definition: types.h:56
#define ip_csum_update(sum, old, new, type, field)
Definition: ip_packet.h:139
#define vnet_buffer(b)
Definition: buffer.h:372
u8 data[0]
Packet data.
Definition: buffer.h:179
void udp_register_dst_port(vlib_main_t *vm, udp_dst_port_t dst_port, u32 node_index, u8 is_ip4)
Definition: udp_local.c:492
u32 mtu
must be first
Definition: udp.h:43
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
udp_connection_t ** connections
Definition: udp.h:134
static_always_inline void clib_spinlock_lock_if_init(clib_spinlock_t *p)
Definition: lock.h:82
udp6_dst_port_t
Definition: udp.h:87
Definition: udp.h:112
static u16 ip_csum_fold(ip_csum_t c)
Definition: ip_packet.h:145
Definition: udp.h:113
format_function_t format_udp_header
Definition: udp.h:240