Line data Source code
1 : /*
2 : * Copyright (c) 2020 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 : #ifndef SRC_VNET_UDP_UDP_INLINES_H_
17 : #define SRC_VNET_UDP_UDP_INLINES_H_
18 :
19 : #include <vnet/vnet.h>
20 : #include <vnet/ip/ip4.h>
21 : #include <vnet/ip/ip6.h>
22 : #include <vnet/udp/udp_packet.h>
23 : #include <vnet/interface_output.h>
24 : #include <vnet/ip/ip4_inlines.h>
25 : #include <vnet/ip/ip6_inlines.h>
26 : #include <vnet/udp/udp_encap.h>
27 :
28 : always_inline void *
29 58172 : vlib_buffer_push_udp (vlib_buffer_t * b, u16 sp, u16 dp, u8 offload_csum)
30 : {
31 : udp_header_t *uh;
32 58172 : u16 udp_len = sizeof (udp_header_t) + b->current_length;
33 58172 : if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
34 0 : udp_len += b->total_length_not_including_first_buffer;
35 :
36 58172 : uh = vlib_buffer_push_uninit (b, sizeof (udp_header_t));
37 58172 : uh->src_port = sp;
38 58172 : uh->dst_port = dp;
39 58172 : uh->checksum = 0;
40 58172 : uh->length = clib_host_to_net_u16 (udp_len);
41 58172 : if (offload_csum)
42 58172 : vnet_buffer_offload_flags_set (b, VNET_BUFFER_OFFLOAD_F_UDP_CKSUM);
43 58172 : vnet_buffer (b)->l4_hdr_offset = (u8 *) uh - b->data;
44 58172 : b->flags |= VNET_BUFFER_F_L4_HDR_OFFSET_VALID;
45 58172 : return uh;
46 : }
47 :
48 : /*
49 : * Encode udp source port entropy value per
50 : * https://datatracker.ietf.org/doc/html/rfc7510#section-3
51 : */
52 : always_inline u16
53 268 : ip_udp_sport_entropy (vlib_buffer_t *b0)
54 : {
55 268 : u16 port = clib_host_to_net_u16 (0x03 << 14);
56 268 : port |= vnet_buffer (b0)->ip.flow_hash & 0xffff;
57 268 : return port;
58 : }
59 :
60 : always_inline u32
61 268 : ip_udp_compute_flow_hash (vlib_buffer_t *b0, u8 is_ip4)
62 : {
63 : ip4_header_t *ip4;
64 : ip6_header_t *ip6;
65 :
66 268 : if (is_ip4)
67 : {
68 134 : ip4 = (ip4_header_t *) (b0->data + vnet_buffer (b0)->l3_hdr_offset);
69 134 : return ip4_compute_flow_hash (ip4, IP_FLOW_HASH_DEFAULT);
70 : }
71 : else
72 : {
73 134 : ip6 = (ip6_header_t *) (b0->data + vnet_buffer (b0)->l3_hdr_offset);
74 134 : return ip6_compute_flow_hash (ip6, IP_FLOW_HASH_DEFAULT);
75 : }
76 : }
77 :
78 : always_inline void
79 29 : ip_udp_fixup_one (vlib_main_t *vm, vlib_buffer_t *b0, u8 is_ip4,
80 : u8 sport_entropy)
81 : {
82 : u16 new_l0;
83 : udp_header_t *udp0;
84 :
85 29 : if (is_ip4)
86 : {
87 : ip4_header_t *ip0;
88 : ip_csum_t sum0;
89 17 : u16 old_l0 = 0;
90 :
91 17 : ip0 = vlib_buffer_get_current (b0);
92 :
93 : /* fix the <bleep>ing outer-IP checksum */
94 17 : sum0 = ip0->checksum;
95 : /* old_l0 always 0, see the rewrite setup */
96 17 : new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
97 :
98 17 : sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
99 : length /* changed member */ );
100 17 : ip0->checksum = ip_csum_fold (sum0);
101 17 : ip0->length = new_l0;
102 :
103 : /* Fix UDP length */
104 17 : udp0 = (udp_header_t *) (ip0 + 1);
105 17 : new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
106 17 : - sizeof (*ip0));
107 17 : udp0->length = new_l0;
108 :
109 17 : if (sport_entropy)
110 6 : udp0->src_port = ip_udp_sport_entropy (b0);
111 : }
112 : else
113 : {
114 : ip6_header_t *ip0;
115 : int bogus0;
116 :
117 12 : ip0 = vlib_buffer_get_current (b0);
118 :
119 12 : new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
120 12 : - sizeof (*ip0));
121 12 : ip0->payload_length = new_l0;
122 :
123 : /* Fix UDP length */
124 12 : udp0 = (udp_header_t *) (ip0 + 1);
125 12 : udp0->length = new_l0;
126 :
127 12 : if (sport_entropy)
128 6 : udp0->src_port = ip_udp_sport_entropy (b0);
129 :
130 12 : udp0->checksum =
131 12 : ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
132 12 : ASSERT (bogus0 == 0);
133 :
134 12 : if (udp0->checksum == 0)
135 0 : udp0->checksum = 0xffff;
136 : }
137 29 : }
138 :
139 : always_inline void
140 28 : ip_udp_encap_one (vlib_main_t *vm, vlib_buffer_t *b0, u8 *ec0, word ec_len,
141 : ip_address_family_t encap_family,
142 : ip_address_family_t payload_family,
143 : udp_encap_fixup_flags_t flags)
144 : {
145 28 : u8 sport_entropy = (flags & UDP_ENCAP_FIXUP_UDP_SRC_PORT_ENTROPY) != 0;
146 :
147 28 : if (payload_family < N_AF)
148 : {
149 28 : vnet_calc_checksums_inline (vm, b0, payload_family == AF_IP4,
150 : payload_family == AF_IP6);
151 :
152 : /* Сalculate flow hash to be used for entropy */
153 28 : if (sport_entropy && 0 == vnet_buffer (b0)->ip.flow_hash)
154 12 : vnet_buffer (b0)->ip.flow_hash =
155 12 : ip_udp_compute_flow_hash (b0, payload_family == AF_IP4);
156 : }
157 :
158 28 : vlib_buffer_advance (b0, -ec_len);
159 :
160 28 : if (encap_family == AF_IP4)
161 : {
162 : ip4_header_t *ip0;
163 :
164 16 : ip0 = vlib_buffer_get_current (b0);
165 :
166 : /* Apply the encap string. */
167 16 : clib_memcpy_fast (ip0, ec0, ec_len);
168 16 : ip_udp_fixup_one (vm, b0, 1, sport_entropy);
169 : }
170 : else
171 : {
172 : ip6_header_t *ip0;
173 :
174 12 : ip0 = vlib_buffer_get_current (b0);
175 :
176 : /* Apply the encap string. */
177 12 : clib_memcpy_fast (ip0, ec0, ec_len);
178 12 : ip_udp_fixup_one (vm, b0, 0, sport_entropy);
179 : }
180 28 : }
181 :
182 : always_inline void
183 288 : ip_udp_encap_two (vlib_main_t *vm, vlib_buffer_t *b0, vlib_buffer_t *b1,
184 : u8 *ec0, u8 *ec1, word ec_len,
185 : ip_address_family_t encap_family,
186 : ip_address_family_t payload_family,
187 : udp_encap_fixup_flags_t flags0,
188 : udp_encap_fixup_flags_t flags1)
189 : {
190 : u16 new_l0, new_l1;
191 : udp_header_t *udp0, *udp1;
192 288 : int payload_ip4 = (payload_family == AF_IP4);
193 288 : int sport_entropy0 = (flags0 & UDP_ENCAP_FIXUP_UDP_SRC_PORT_ENTROPY) != 0;
194 288 : int sport_entropy1 = (flags1 & UDP_ENCAP_FIXUP_UDP_SRC_PORT_ENTROPY) != 0;
195 :
196 288 : if (payload_family < N_AF)
197 : {
198 288 : vnet_calc_checksums_inline (vm, b0, payload_ip4, !payload_ip4);
199 288 : vnet_calc_checksums_inline (vm, b1, payload_ip4, !payload_ip4);
200 :
201 : /* Сalculate flow hash to be used for entropy */
202 288 : if (sport_entropy0 && 0 == vnet_buffer (b0)->ip.flow_hash)
203 128 : vnet_buffer (b0)->ip.flow_hash =
204 128 : ip_udp_compute_flow_hash (b0, payload_ip4);
205 288 : if (sport_entropy1 && 0 == vnet_buffer (b1)->ip.flow_hash)
206 128 : vnet_buffer (b1)->ip.flow_hash =
207 128 : ip_udp_compute_flow_hash (b1, payload_ip4);
208 : }
209 :
210 288 : vlib_buffer_advance (b0, -ec_len);
211 288 : vlib_buffer_advance (b1, -ec_len);
212 :
213 288 : if (encap_family == AF_IP4)
214 : {
215 : ip4_header_t *ip0, *ip1;
216 : ip_csum_t sum0, sum1;
217 160 : u16 old_l0 = 0, old_l1 = 0;
218 :
219 160 : ip0 = vlib_buffer_get_current (b0);
220 160 : ip1 = vlib_buffer_get_current (b1);
221 :
222 : /* Apply the encap string */
223 160 : clib_memcpy_fast (ip0, ec0, ec_len);
224 160 : clib_memcpy_fast (ip1, ec1, ec_len);
225 :
226 : /* fix the <bleep>ing outer-IP checksum */
227 160 : sum0 = ip0->checksum;
228 160 : sum1 = ip1->checksum;
229 :
230 : /* old_l0 always 0, see the rewrite setup */
231 160 : new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
232 160 : new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1));
233 :
234 160 : sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
235 : length /* changed member */ );
236 160 : sum1 = ip_csum_update (sum1, old_l1, new_l1, ip4_header_t,
237 : length /* changed member */ );
238 :
239 160 : ip0->checksum = ip_csum_fold (sum0);
240 160 : ip1->checksum = ip_csum_fold (sum1);
241 :
242 160 : ip0->length = new_l0;
243 160 : ip1->length = new_l1;
244 :
245 : /* Fix UDP length */
246 160 : udp0 = (udp_header_t *) (ip0 + 1);
247 160 : udp1 = (udp_header_t *) (ip1 + 1);
248 :
249 : new_l0 =
250 160 : clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
251 : sizeof (*ip0));
252 : new_l1 =
253 160 : clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1) -
254 : sizeof (*ip1));
255 160 : udp0->length = new_l0;
256 160 : udp1->length = new_l1;
257 :
258 160 : if (sport_entropy0)
259 64 : udp0->src_port = ip_udp_sport_entropy (b0);
260 160 : if (sport_entropy1)
261 64 : udp1->src_port = ip_udp_sport_entropy (b1);
262 : }
263 : else
264 : {
265 : ip6_header_t *ip0, *ip1;
266 : int bogus0, bogus1;
267 :
268 128 : ip0 = vlib_buffer_get_current (b0);
269 128 : ip1 = vlib_buffer_get_current (b1);
270 :
271 : /* Apply the encap string. */
272 128 : clib_memcpy_fast (ip0, ec0, ec_len);
273 128 : clib_memcpy_fast (ip1, ec1, ec_len);
274 :
275 128 : new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
276 128 : - sizeof (*ip0));
277 128 : new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1)
278 128 : - sizeof (*ip1));
279 128 : ip0->payload_length = new_l0;
280 128 : ip1->payload_length = new_l1;
281 :
282 : /* Fix UDP length */
283 128 : udp0 = (udp_header_t *) (ip0 + 1);
284 128 : udp1 = (udp_header_t *) (ip1 + 1);
285 :
286 128 : udp0->length = new_l0;
287 128 : udp1->length = new_l1;
288 :
289 128 : if (sport_entropy0)
290 64 : udp0->src_port = ip_udp_sport_entropy (b0);
291 128 : if (sport_entropy1)
292 64 : udp1->src_port = ip_udp_sport_entropy (b1);
293 :
294 128 : udp0->checksum =
295 128 : ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
296 128 : udp1->checksum =
297 128 : ip6_tcp_udp_icmp_compute_checksum (vm, b1, ip1, &bogus1);
298 128 : ASSERT (bogus0 == 0);
299 128 : ASSERT (bogus1 == 0);
300 :
301 128 : if (udp0->checksum == 0)
302 0 : udp0->checksum = 0xffff;
303 128 : if (udp1->checksum == 0)
304 0 : udp1->checksum = 0xffff;
305 : }
306 288 : }
307 :
308 : #endif /* SRC_VNET_UDP_UDP_INLINES_H_ */
309 :
310 : /*
311 : * fd.io coding-style-patch-verification: ON
312 : *
313 : * Local Variables:
314 : * eval: (c-set-style "gnu")
315 : * End:
316 : */
|
