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Vector Packet Processing
udp.h
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1 /*
2  * ip/udp.h: udp protocol
3  *
4  * Copyright (c) 2013 Cisco and/or its affiliates.
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at:
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 #ifndef included_udp_h
19 #define included_udp_h
20 
21 #include <vnet/vnet.h>
22 #include <vnet/ip/udp_packet.h>
23 #include <vnet/ip/ip.h>
24 #include <vnet/ip/ip4.h>
25 #include <vnet/ip/ip4_packet.h>
26 #include <vnet/pg/pg.h>
27 #include <vnet/ip/format.h>
28 
29 typedef enum
30 {
31 #define udp_error(n,s) UDP_ERROR_##n,
32 #include <vnet/ip/udp_error.def>
33 #undef udp_error
34  UDP_N_ERROR,
35 } udp_error_t;
36 
37 #define foreach_udp4_dst_port \
38 _ (67, dhcp_to_server) \
39 _ (68, dhcp_to_client) \
40 _ (500, ikev2) \
41 _ (3784, bfd4) \
42 _ (4341, lisp_gpe) \
43 _ (4342, lisp_cp) \
44 _ (4739, ipfix) \
45 _ (4789, vxlan) \
46 _ (4789, vxlan6) \
47 _ (4790, vxlan_gpe) \
48 _ (6633, vpath_3)
49 
50 
51 #define foreach_udp6_dst_port \
52 _ (547, dhcpv6_to_server) \
53 _ (546, dhcpv6_to_client) \
54 _ (3784, bfd6) \
55 _ (4341, lisp_gpe6) \
56 _ (4342, lisp_cp6) \
57 _ (4790, vxlan6_gpe) \
58 _ (6633, vpath6_3)
59 
60 typedef enum
61 {
62 #define _(n,f) UDP_DST_PORT_##f = n,
64 #undef _
66 
67 typedef enum
68 {
69 #define _(n,f) UDP6_DST_PORT_##f = n,
71 #undef _
73 
74 typedef struct
75 {
76  /* Name (a c string). */
77  char *name;
78 
79  /* GRE protocol type in host byte order. */
81 
82  /* Node which handles this type. */
84 
85  /* Next index for this type. */
88 
89 typedef enum
90 {
91  UDP_IP6 = 0,
92  UDP_IP4, /* the code is full of is_ip4... */
94 } udp_af_t;
95 
96 typedef struct
97 {
98  udp_dst_port_info_t *dst_port_infos[N_UDP_AF];
99 
100  /* Hash tables mapping name/protocol to protocol info index. */
101  uword *dst_port_info_by_name[N_UDP_AF];
102  uword *dst_port_info_by_dst_port[N_UDP_AF];
103 
104  /* convenience */
106 } udp_main_t;
107 
110 {
111  uword *p = hash_get (um->dst_port_info_by_dst_port[is_ip4], dst_port);
112  return p ? vec_elt_at_index (um->dst_port_infos[is_ip4], p[0]) : 0;
113 }
114 
117 
119 
121  udp_dst_port_t dst_port,
122  u32 node_index, u8 is_ip4);
123 
124 void udp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
125 
126 always_inline void
128 {
129  u16 new_l0;
130  udp_header_t *udp0;
131 
132  if (is_ip4)
133  {
134  ip4_header_t *ip0;
135  ip_csum_t sum0;
136  u16 old_l0 = 0;
137 
138  ip0 = vlib_buffer_get_current (b0);
139 
140  /* fix the <bleep>ing outer-IP checksum */
141  sum0 = ip0->checksum;
142  /* old_l0 always 0, see the rewrite setup */
143  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
144 
145  sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
146  length /* changed member */ );
147  ip0->checksum = ip_csum_fold (sum0);
148  ip0->length = new_l0;
149 
150  /* Fix UDP length */
151  udp0 = (udp_header_t *) (ip0 + 1);
152  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
153  - sizeof (*ip0));
154  udp0->length = new_l0;
155  }
156  else
157  {
158  ip6_header_t *ip0;
159  int bogus0;
160 
161  ip0 = vlib_buffer_get_current (b0);
162 
163  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
164  - sizeof (*ip0));
165  ip0->payload_length = new_l0;
166 
167  /* Fix UDP length */
168  udp0 = (udp_header_t *) (ip0 + 1);
169  udp0->length = new_l0;
170 
171  udp0->checksum =
172  ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
173  ASSERT (bogus0 == 0);
174 
175  if (udp0->checksum == 0)
176  udp0->checksum = 0xffff;
177  }
178 }
179 
180 always_inline void
181 ip_udp_encap_one (vlib_main_t * vm, vlib_buffer_t * b0, u8 * ec0, word ec_len,
182  u8 is_ip4)
183 {
184  vlib_buffer_advance (b0, -ec_len);
185 
186  if (is_ip4)
187  {
188  ip4_header_t *ip0;
189 
190  ip0 = vlib_buffer_get_current (b0);
191 
192  /* Apply the encap string. */
193  clib_memcpy (ip0, ec0, ec_len);
194  ip_udp_fixup_one (vm, b0, 1);
195  }
196  else
197  {
198  ip6_header_t *ip0;
199 
200  ip0 = vlib_buffer_get_current (b0);
201 
202  /* Apply the encap string. */
203  clib_memcpy (ip0, ec0, ec_len);
204  ip_udp_fixup_one (vm, b0, 0);
205  }
206 }
207 
208 always_inline void
210  u8 * ec0, u8 * ec1, word ec_len, u8 is_v4)
211 {
212  u16 new_l0, new_l1;
213  udp_header_t *udp0, *udp1;
214 
215  ASSERT (_vec_len (ec0) == _vec_len (ec1));
216 
217  vlib_buffer_advance (b0, -ec_len);
218  vlib_buffer_advance (b1, -ec_len);
219 
220  if (is_v4)
221  {
222  ip4_header_t *ip0, *ip1;
223  ip_csum_t sum0, sum1;
224  u16 old_l0 = 0, old_l1 = 0;
225 
226  ip0 = vlib_buffer_get_current (b0);
227  ip1 = vlib_buffer_get_current (b1);
228 
229  /* Apply the encap string */
230  clib_memcpy (ip0, ec0, ec_len);
231  clib_memcpy (ip1, ec1, ec_len);
232 
233  /* fix the <bleep>ing outer-IP checksum */
234  sum0 = ip0->checksum;
235  sum1 = ip1->checksum;
236 
237  /* old_l0 always 0, see the rewrite setup */
238  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
239  new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1));
240 
241  sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
242  length /* changed member */ );
243  sum1 = ip_csum_update (sum1, old_l1, new_l1, ip4_header_t,
244  length /* changed member */ );
245 
246  ip0->checksum = ip_csum_fold (sum0);
247  ip1->checksum = ip_csum_fold (sum1);
248 
249  ip0->length = new_l0;
250  ip1->length = new_l1;
251 
252  /* Fix UDP length */
253  udp0 = (udp_header_t *) (ip0 + 1);
254  udp1 = (udp_header_t *) (ip1 + 1);
255 
256  new_l0 =
257  clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
258  sizeof (*ip0));
259  new_l1 =
260  clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1) -
261  sizeof (*ip1));
262  udp0->length = new_l0;
263  udp1->length = new_l1;
264  }
265  else
266  {
267  ip6_header_t *ip0, *ip1;
268  int bogus0, bogus1;
269 
270  ip0 = vlib_buffer_get_current (b0);
271  ip1 = vlib_buffer_get_current (b1);
272 
273  /* Apply the encap string. */
274  clib_memcpy (ip0, ec0, ec_len);
275  clib_memcpy (ip1, ec1, ec_len);
276 
277  new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
278  - sizeof (*ip0));
279  new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1)
280  - sizeof (*ip1));
281  ip0->payload_length = new_l0;
282  ip1->payload_length = new_l1;
283 
284  /* Fix UDP length */
285  udp0 = (udp_header_t *) (ip0 + 1);
286  udp1 = (udp_header_t *) (ip1 + 1);
287 
288  udp0->length = new_l0;
289  udp1->length = new_l1;
290 
291  udp0->checksum =
292  ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
293  udp1->checksum =
294  ip6_tcp_udp_icmp_compute_checksum (vm, b1, ip1, &bogus1);
295  ASSERT (bogus0 == 0);
296  ASSERT (bogus1 == 0);
297 
298  if (udp0->checksum == 0)
299  udp0->checksum = 0xffff;
300  if (udp1->checksum == 0)
301  udp1->checksum = 0xffff;
302  }
303 }
304 
305 #endif /* included_udp_h */
306 
307 /*
308  * fd.io coding-style-patch-verification: ON
309  *
310  * Local Variables:
311  * eval: (c-set-style "gnu")
312  * End:
313  */
unformat_function_t unformat_udp_header
Definition: udp.h:118
uword( unformat_function_t)(unformat_input_t *input, va_list *args)
Definition: format.h:231
uword * dst_port_info_by_dst_port[N_UDP_AF]
Definition: udp.h:102
Definition: udp.h:96
u32 node_index
Definition: udp.h:83
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:109
uword ip_csum_t
Definition: ip_packet.h:90
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
#define always_inline
Definition: clib.h:84
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:194
#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:51
#define hash_get(h, key)
Definition: hash.h:248
udp_dst_port_info_t * dst_port_infos[N_UDP_AF]
Definition: udp.h:98
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:181
Definition: udp.h:91
void udp_punt_unknown(vlib_main_t *vm, u8 is_ip4, u8 is_add)
Definition: udp_local.c:531
static void ip_udp_fixup_one(vlib_main_t *vm, vlib_buffer_t *b0, u8 is_ip4)
Definition: udp.h:127
format_function_t format_udp_rx_trace
Definition: udp.h:116
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:209
#define clib_memcpy(a, b, c)
Definition: string.h:69
static void vlib_buffer_advance(vlib_buffer_t *b, word l)
Advance current data pointer by the supplied (signed!) amount.
Definition: buffer.h:207
udp_error_t
Definition: udp.h:29
udp_dst_port_t
Definition: udp.h:60
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:1141
#define foreach_udp4_dst_port
Definition: udp.h:37
#define ASSERT(truth)
unsigned int u32
Definition: types.h:88
udp_af_t
Definition: udp.h:89
udp_dst_port_t dst_port
Definition: udp.h:80
char * name
Definition: udp.h:77
u8 *( format_function_t)(u8 *s, va_list *args)
Definition: format.h:48
u64 uword
Definition: types.h:112
unsigned short u16
Definition: types.h:57
u16 payload_length
Definition: ip6_packet.h:328
i64 word
Definition: types.h:111
unsigned char u8
Definition: types.h:56
#define ip_csum_update(sum, old, new, type, field)
Definition: ip_packet.h:139
u32 next_index
Definition: udp.h:86
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:495
vlib_main_t * vlib_main
Definition: udp.h:105
udp6_dst_port_t
Definition: udp.h:67
Definition: udp.h:92
static u16 ip_csum_fold(ip_csum_t c)
Definition: ip_packet.h:145
Definition: udp.h:93
format_function_t format_udp_header
Definition: udp.h:115