FD.io VPP  v18.07-34-g55fbdb9
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  clib_spinlock_t rx_lock; /**< rx fifo lock */
43  u8 is_connected; /**< connected mode */
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 _ (4500, ipsec) \
57 _ (4739, ipfix) \
58 _ (4789, vxlan) \
59 _ (4789, vxlan6) \
60 _ (4790, VXLAN_GPE) \
61 _ (6633, vpath_3) \
62 _ (6081, geneve) \
63 _ (53053, dns_reply)
64 
65 
66 #define foreach_udp6_dst_port \
67 _ (53, dns6) \
68 _ (547, dhcpv6_to_server) \
69 _ (546, dhcpv6_to_client) \
70 _ (2152, GTPU6) \
71 _ (3784, bfd6) \
72 _ (3785, bfd_echo6) \
73 _ (4341, lisp_gpe6) \
74 _ (4342, lisp_cp6) \
75 _ (4790, VXLAN6_GPE) \
76 _ (6633, vpath6_3) \
77 _ (6081, geneve6) \
78 _ (8138, BIER) \
79 _ (53053, dns_reply6)
80 
81 typedef enum
82 {
83 #define _(n,f) UDP_DST_PORT_##f = n,
85 #undef _
87 
88 typedef enum
89 {
90 #define _(n,f) UDP6_DST_PORT_##f = n,
92 #undef _
94 
95 typedef struct
96 {
97  /* Name (a c string). */
98  char *name;
99 
100  /* GRE protocol type in host byte order. */
102 
103  /* Node which handles this type. */
105 
106  /* Next index for this type. */
109 
110 typedef enum
111 {
112  UDP_IP6 = 0,
113  UDP_IP4, /* the code is full of is_ip4... */
115 } udp_af_t;
116 
117 typedef struct
118 {
119  udp_dst_port_info_t *dst_port_infos[N_UDP_AF];
120 
121  /* Hash tables mapping name/protocol to protocol info index. */
122  uword *dst_port_info_by_name[N_UDP_AF];
123  uword *dst_port_info_by_dst_port[N_UDP_AF];
124 
125  /* Sparse vector mapping udp dst_port in network byte order
126  to next index. */
131 
132  /*
133  * Per-worker thread udp connection pools used with session layer
134  */
140 
141 } udp_main_t;
142 
143 extern udp_main_t udp_main;
146 
148 udp_connection_get (u32 conn_index, u32 thread_index)
149 {
150  if (pool_is_free_index (udp_main.connections[thread_index], conn_index))
151  return 0;
152  return pool_elt_at_index (udp_main.connections[thread_index], conn_index);
153 }
154 
156 udp_listener_get (u32 conn_index)
157 {
158  return pool_elt_at_index (udp_main.listener_pool, conn_index);
159 }
160 
163 {
164  return &udp_main;
165 }
166 
169 {
170  return ((udp_connection_t *) tc);
171 }
172 
175 {
176  return (uc - udp_main.connections[uc->c_thread_index]);
177 }
178 
180 
181 /**
182  * Acquires a lock that blocks a connection pool from expanding.
183  */
184 always_inline void
185 udp_pool_add_peeker (u32 thread_index)
186 {
187  if (thread_index != vlib_get_thread_index ())
188  return;
189  clib_spinlock_lock_if_init (&udp_main.peekers_readers_locks[thread_index]);
190  udp_main.connection_peekers[thread_index] += 1;
191  if (udp_main.connection_peekers[thread_index] == 1)
192  clib_spinlock_lock_if_init (&udp_main.peekers_write_locks[thread_index]);
194  [thread_index]);
195 }
196 
197 always_inline void
199 {
200  if (thread_index != vlib_get_thread_index ())
201  return;
202  ASSERT (udp_main.connection_peekers[thread_index] > 0);
203  clib_spinlock_lock_if_init (&udp_main.peekers_readers_locks[thread_index]);
204  udp_main.connection_peekers[thread_index] -= 1;
205  if (udp_main.connection_peekers[thread_index] == 0)
207  [thread_index]);
209  [thread_index]);
210 }
211 
213 udp_connection_clone_safe (u32 connection_index, u32 thread_index)
214 {
215  udp_connection_t *old_c, *new_c;
216  u32 current_thread_index = vlib_get_thread_index ();
217  new_c = udp_connection_alloc (current_thread_index);
218 
219  /* If during the memcpy pool is reallocated AND the memory allocator
220  * decides to give the old chunk of memory to somebody in a hurry to
221  * scribble something on it, we have a problem. So add this thread as
222  * a session pool peeker.
223  */
224  udp_pool_add_peeker (thread_index);
225  old_c = udp_main.connections[thread_index] + connection_index;
226  clib_memcpy (new_c, old_c, sizeof (*new_c));
227  udp_pool_remove_peeker (thread_index);
228  new_c->c_thread_index = current_thread_index;
229  new_c->c_c_index = udp_connection_index (new_c);
230  return new_c;
231 }
232 
233 
236 {
237  uword *p = hash_get (um->dst_port_info_by_dst_port[is_ip4], dst_port);
238  return p ? vec_elt_at_index (um->dst_port_infos[is_ip4], p[0]) : 0;
239 }
240 
244 
246  udp_dst_port_t dst_port,
247  u32 node_index, u8 is_ip4);
249  udp_dst_port_t dst_port, u8 is_ip4);
250 
251 void udp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
252 
253 always_inline void *
254 vlib_buffer_push_udp (vlib_buffer_t * b, u16 sp, u16 dp, u8 offload_csum)
255 {
256  udp_header_t *uh;
257 
258  uh = vlib_buffer_push_uninit (b, sizeof (udp_header_t));
259  uh->src_port = sp;
260  uh->dst_port = dp;
261  uh->checksum = 0;
262  uh->length = clib_host_to_net_u16 (b->current_length);
263  if (offload_csum)
264  {
265  b->flags |= VNET_BUFFER_F_OFFLOAD_UDP_CKSUM;
266  vnet_buffer (b)->l4_hdr_offset = (u8 *) uh - b->data;
267  }
268  return uh;
269 }
270 
271 always_inline void
273 {
274  u16 new_l0;
275  udp_header_t *udp0;
276 
277  if (is_ip4)
278  {
279  ip4_header_t *ip0;
280  ip_csum_t sum0;
281  u16 old_l0 = 0;
282 
283  ip0 = vlib_buffer_get_current (b0);
284 
285  /* fix the <bleep>ing outer-IP checksum */
286  sum0 = ip0->checksum;
287  /* old_l0 always 0, see the rewrite setup */
288  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
289 
290  sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
291  length /* changed member */ );
292  ip0->checksum = ip_csum_fold (sum0);
293  ip0->length = new_l0;
294 
295  /* Fix UDP length */
296  udp0 = (udp_header_t *) (ip0 + 1);
297  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
298  - sizeof (*ip0));
299  udp0->length = new_l0;
300  }
301  else
302  {
303  ip6_header_t *ip0;
304  int bogus0;
305 
306  ip0 = vlib_buffer_get_current (b0);
307 
308  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
309  - sizeof (*ip0));
310  ip0->payload_length = new_l0;
311 
312  /* Fix UDP length */
313  udp0 = (udp_header_t *) (ip0 + 1);
314  udp0->length = new_l0;
315 
316  udp0->checksum =
317  ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
318  ASSERT (bogus0 == 0);
319 
320  if (udp0->checksum == 0)
321  udp0->checksum = 0xffff;
322  }
323 }
324 
325 always_inline void
327  u8 is_ip4)
328 {
329  vlib_buffer_advance (b0, -ec_len);
330 
331  if (is_ip4)
332  {
333  ip4_header_t *ip0;
334 
335  ip0 = vlib_buffer_get_current (b0);
336 
337  /* Apply the encap string. */
338  clib_memcpy (ip0, ec0, ec_len);
339  ip_udp_fixup_one (vm, b0, 1);
340  }
341  else
342  {
343  ip6_header_t *ip0;
344 
345  ip0 = vlib_buffer_get_current (b0);
346 
347  /* Apply the encap string. */
348  clib_memcpy (ip0, ec0, ec_len);
349  ip_udp_fixup_one (vm, b0, 0);
350  }
351 }
352 
353 always_inline void
355  u8 * ec0, u8 * ec1, word ec_len, u8 is_v4)
356 {
357  u16 new_l0, new_l1;
358  udp_header_t *udp0, *udp1;
359 
360  ASSERT (_vec_len (ec0) == _vec_len (ec1));
361 
362  vlib_buffer_advance (b0, -ec_len);
363  vlib_buffer_advance (b1, -ec_len);
364 
365  if (is_v4)
366  {
367  ip4_header_t *ip0, *ip1;
368  ip_csum_t sum0, sum1;
369  u16 old_l0 = 0, old_l1 = 0;
370 
371  ip0 = vlib_buffer_get_current (b0);
372  ip1 = vlib_buffer_get_current (b1);
373 
374  /* Apply the encap string */
375  clib_memcpy (ip0, ec0, ec_len);
376  clib_memcpy (ip1, ec1, ec_len);
377 
378  /* fix the <bleep>ing outer-IP checksum */
379  sum0 = ip0->checksum;
380  sum1 = ip1->checksum;
381 
382  /* old_l0 always 0, see the rewrite setup */
383  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
384  new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1));
385 
386  sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
387  length /* changed member */ );
388  sum1 = ip_csum_update (sum1, old_l1, new_l1, ip4_header_t,
389  length /* changed member */ );
390 
391  ip0->checksum = ip_csum_fold (sum0);
392  ip1->checksum = ip_csum_fold (sum1);
393 
394  ip0->length = new_l0;
395  ip1->length = new_l1;
396 
397  /* Fix UDP length */
398  udp0 = (udp_header_t *) (ip0 + 1);
399  udp1 = (udp_header_t *) (ip1 + 1);
400 
401  new_l0 =
402  clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
403  sizeof (*ip0));
404  new_l1 =
405  clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1) -
406  sizeof (*ip1));
407  udp0->length = new_l0;
408  udp1->length = new_l1;
409  }
410  else
411  {
412  ip6_header_t *ip0, *ip1;
413  int bogus0, bogus1;
414 
415  ip0 = vlib_buffer_get_current (b0);
416  ip1 = vlib_buffer_get_current (b1);
417 
418  /* Apply the encap string. */
419  clib_memcpy (ip0, ec0, ec_len);
420  clib_memcpy (ip1, ec1, ec_len);
421 
422  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
423  - sizeof (*ip0));
424  new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1)
425  - sizeof (*ip1));
426  ip0->payload_length = new_l0;
427  ip1->payload_length = new_l1;
428 
429  /* Fix UDP length */
430  udp0 = (udp_header_t *) (ip0 + 1);
431  udp1 = (udp_header_t *) (ip1 + 1);
432 
433  udp0->length = new_l0;
434  udp1->length = new_l1;
435 
436  udp0->checksum =
437  ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
438  udp1->checksum =
439  ip6_tcp_udp_icmp_compute_checksum (vm, b1, ip1, &bogus1);
440  ASSERT (bogus0 == 0);
441  ASSERT (bogus1 == 0);
442 
443  if (udp0->checksum == 0)
444  udp0->checksum = 0xffff;
445  if (udp1->checksum == 0)
446  udp1->checksum = 0xffff;
447  }
448 }
449 
450 /*
451  * fd.io coding-style-patch-verification: ON
452  *
453  * Local Variables:
454  * eval: (c-set-style "gnu")
455  * End:
456  */
457 
458 #endif /* __included_udp_h__ */
uword( unformat_function_t)(unformat_input_t *input, va_list *args)
Definition: format.h:232
static udp_connection_t * udp_listener_get(u32 conn_index)
Definition: udp.h:156
#define CLIB_CACHE_LINE_ALIGN_MARK(mark)
Definition: cache.h:63
u16 * next_by_dst_port6
Definition: udp.h:128
unformat_function_t unformat_udp_header
Definition: udp.h:243
struct _transport_connection transport_connection_t
u32 * connection_peekers
Definition: udp.h:136
uword * dst_port_info_by_dst_port[N_UDP_AF]
Definition: udp.h:123
static udp_connection_t * udp_get_connection_from_transport(transport_connection_t *tc)
Definition: udp.h:168
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:235
uword ip_csum_t
Definition: ip_packet.h:181
u8 *( format_function_t)(u8 *s, va_list *args)
Definition: format.h:48
u8 punt_unknown6
Definition: udp.h:130
static void * vlib_buffer_push_udp(vlib_buffer_t *b, u16 sp, u16 dp, u8 offload_csum)
Definition: udp.h:254
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:250
unsigned char u8
Definition: types.h:56
static udp_main_t * vnet_get_udp_main()
Definition: udp.h:162
i64 word
Definition: types.h:111
#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:129
#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:66
unsigned int u32
Definition: types.h:88
static void udp_pool_remove_peeker(u32 thread_index)
Definition: udp.h:198
vlib_node_registration_t udp4_input_node
(constructor) VLIB_REGISTER_NODE (udp4_input_node)
Definition: udp_input.c:307
#define hash_get(h, key)
Definition: hash.h:249
#define pool_elt_at_index(p, i)
Returns pointer to element at given index.
Definition: pool.h:464
u16 * next_by_dst_port4
Definition: udp.h:127
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:174
udp_dst_port_info_t * dst_port_infos[N_UDP_AF]
Definition: udp.h:119
unsigned short u16
Definition: types.h:57
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:202
clib_spinlock_t * peekers_readers_locks
Definition: udp.h:137
vlib_node_registration_t udp6_input_node
(constructor) VLIB_REGISTER_NODE (udp6_input_node)
Definition: udp_input.c:333
udp_connection_t * listener_pool
Definition: udp.h:139
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:326
Definition: udp.h:112
static void udp_pool_add_peeker(u32 thread_index)
Acquires a lock that blocks a connection pool from expanding.
Definition: udp.h:185
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:272
format_function_t format_udp_rx_trace
Definition: udp.h:242
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:354
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:148
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:271
udp_dst_port_t
Definition: udp.h:81
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:910
#define foreach_udp4_dst_port
Definition: udp.h:46
#define ASSERT(truth)
udp_af_t
Definition: udp.h:110
udp_dst_port_t dst_port
Definition: udp.h:101
char * name
Definition: udp.h:98
static void vlib_buffer_advance(vlib_buffer_t *b, word l)
Advance current data pointer by the supplied (signed!) amount.
Definition: buffer.h:215
clib_spinlock_t * peekers_write_locks
Definition: udp.h:138
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:299
u16 payload_length
Definition: ip6_packet.h:338
transport_connection_t connection
must be first
Definition: udp.h:41
clib_spinlock_t rx_lock
rx fifo lock
Definition: udp.h:42
u64 uword
Definition: types.h:112
#define ip_csum_update(sum, old, new, type, field)
Definition: ip_packet.h:231
#define vnet_buffer(b)
Definition: buffer.h:360
u8 data[0]
Packet data.
Definition: buffer.h:172
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
static udp_connection_t * udp_connection_clone_safe(u32 connection_index, u32 thread_index)
Definition: udp.h:213
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:135
static_always_inline void clib_spinlock_lock_if_init(clib_spinlock_t *p)
Definition: lock.h:82
udp6_dst_port_t
Definition: udp.h:88
Definition: udp.h:113
static u16 ip_csum_fold(ip_csum_t c)
Definition: ip_packet.h:237
Definition: udp.h:114
u8 is_connected
connected mode
Definition: udp.h:43
format_function_t format_udp_header
Definition: udp.h:241