FD.io VPP  v21.01.1
Vector Packet Processing
ip_packet.h
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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 /*
16  * ip/ip_packet.h: packet format common between ip4 & ip6
17  *
18  * Copyright (c) 2008 Eliot Dresselhaus
19  *
20  * Permission is hereby granted, free of charge, to any person obtaining
21  * a copy of this software and associated documentation files (the
22  * "Software"), to deal in the Software without restriction, including
23  * without limitation the rights to use, copy, modify, merge, publish,
24  * distribute, sublicense, and/or sell copies of the Software, and to
25  * permit persons to whom the Software is furnished to do so, subject to
26  * the following conditions:
27  *
28  * The above copyright notice and this permission notice shall be
29  * included in all copies or substantial portions of the Software.
30  *
31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
38  */
39 
40 #ifndef included_ip_packet_h
41 #define included_ip_packet_h
42 
43 #include <vppinfra/byte_order.h>
44 #include <vppinfra/error.h>
45 #include <vppinfra/format.h>
46 
47 typedef enum ip_protocol
48 {
49 #define ip_protocol(n,s) IP_PROTOCOL_##s = n,
50 #include "protocols.def"
51 #undef ip_protocol
52 } __clib_packed ip_protocol_t;
53 
54 /* TCP/UDP ports. */
55 typedef enum
56 {
57 #define ip_port(s,n) IP_PORT_##s = n,
58 #include "ports.def"
59 #undef ip_port
60 } ip_port_t;
61 
62 /* Classifies protocols into UDP, ICMP or other. */
63 typedef enum
64 {
69 
70 #define foreach_ip_builtin_multicast_group \
71  _ (1, all_hosts_on_subnet) \
72  _ (2, all_routers_on_subnet) \
73  _ (4, dvmrp) \
74  _ (5, ospf_all_routers) \
75  _ (6, ospf_designated_routers) \
76  _ (13, pim) \
77  _ (18, vrrp) \
78  _ (102, hsrp) \
79  _ (22, igmp_v3)
80 
81 typedef enum
82 {
83 #define _(n,f) IP_MULTICAST_GROUP_##f = n,
85 #undef _
87 
88 
89 /**
90  * The set of RFC defined DSCP values.
91  */
92 #define foreach_ip_dscp \
93  _(0, CS0) \
94  _(8, CS1) \
95  _(10, AF11) \
96  _(12, AF12) \
97  _(14, AF13) \
98  _(16, CS2) \
99  _(18, AF21) \
100  _(20, AF22) \
101  _(22, AF23) \
102  _(24, CS3) \
103  _(26, AF31) \
104  _(28, AF32) \
105  _(30, AF33) \
106  _(32, CS4) \
107  _(34, AF41) \
108  _(36, AF42) \
109  _(38, AF43) \
110  _(40, CS5) \
111  _(46, EF) \
112  _(48, CS6) \
113  _(50, CS7)
114 
115 typedef enum ip_dscp_t_
116 {
117 #define _(n,f) IP_DSCP_##f = n,
119 #undef _
120 } __clib_packed ip_dscp_t;
121 
122 extern u8 *format_ip_dscp (u8 * s, va_list * va);
124 
125 /**
126  * IP DSCP bit shift
127  * The ECN occupies the 2 least significant bits of the TC field
128  */
129 #define IP_PACKET_TC_FIELD_DSCP_BIT_SHIFT 2
130 #define IP_PACKET_TC_FIELD_ECN_MASK 0x03
131 
132 /**
133  * The set of RFC defined DSCP values.
134  */
135 #define foreach_ip_ecn \
136  _(0, NON_ECN) \
137  _(1, ECT_0) \
138  _(2, ECT_1) \
139  _(3, CE)
140 
141 typedef enum ip_ecn_t_
142 {
143 #define _(n,f) IP_ECN_##f = n,
145 #undef _
146 } __clib_packed ip_ecn_t;
147 
149 
150 extern u8 *format_ip_ecn (u8 * s, va_list * va);
151 
152 /* IP checksum support. */
153 
155 ip_csum (void *data, u16 n_left)
156 {
157  u32 sum;
158 #ifdef CLIB_HAVE_VEC256
159  u16x16 v1, v2;
160  u32x8 zero = { 0 };
161  u32x8 sum8 = { 0 };
162  u32x4 sum4;
163 #endif
164 
165  /* if there is odd number of bytes, pad by zero and store in sum */
166  sum = (n_left & 1) ? ((u8 *) data)[n_left - 1] << 8 : 0;
167 
168  /* we deal with words */
169  n_left >>= 1;
170 
171 #ifdef CLIB_HAVE_VEC256
172  while (n_left >= 32)
173  {
174  v1 = u16x16_load_unaligned (data);
175  v2 = u16x16_load_unaligned (data + 32);
176 
177 #ifdef CLIB_ARCH_IS_LITTLE_ENDIAN
178  v1 = u16x16_byte_swap (v1);
179  v2 = u16x16_byte_swap (v2);
180 #endif
181  sum8 += u32x8_from_u16x8 (u16x16_extract_lo (v1));
182  sum8 += u32x8_from_u16x8 (u16x16_extract_hi (v1));
183  sum8 += u32x8_from_u16x8 (u16x16_extract_lo (v2));
184  sum8 += u32x8_from_u16x8 (u16x16_extract_hi (v2));
185  n_left -= 32;
186  data += 64;
187  }
188 
189  if (n_left >= 16)
190  {
191  v1 = u16x16_load_unaligned (data);
192 #ifdef CLIB_ARCH_IS_LITTLE_ENDIAN
193  v1 = u16x16_byte_swap (v1);
194 #endif
195  v1 = u16x16_byte_swap (u16x16_load_unaligned (data));
196  sum8 += u32x8_from_u16x8 (u16x16_extract_lo (v1));
197  sum8 += u32x8_from_u16x8 (u16x16_extract_hi (v1));
198  n_left -= 16;
199  data += 32;
200  }
201 
202  if (n_left)
203  {
204  v1 = u16x16_load_unaligned (data);
205 #ifdef CLIB_ARCH_IS_LITTLE_ENDIAN
206  v1 = u16x16_byte_swap (v1);
207 #endif
208  v1 = u16x16_mask_last (v1, 16 - n_left);
209  sum8 += u32x8_from_u16x8 (u16x16_extract_lo (v1));
210  sum8 += u32x8_from_u16x8 (u16x16_extract_hi (v1));
211  }
212 
213  sum8 = u32x8_hadd (sum8, zero);
214  sum4 = u32x8_extract_lo (sum8) + u32x8_extract_hi (sum8);
215  sum = sum4[0] + sum4[1];
216 
217 #else
218  /* scalar version */
219  while (n_left >= 8)
220  {
221  sum += clib_net_to_host_u16 (*((u16 *) data + 0));
222  sum += clib_net_to_host_u16 (*((u16 *) data + 1));
223  sum += clib_net_to_host_u16 (*((u16 *) data + 2));
224  sum += clib_net_to_host_u16 (*((u16 *) data + 3));
225  sum += clib_net_to_host_u16 (*((u16 *) data + 4));
226  sum += clib_net_to_host_u16 (*((u16 *) data + 5));
227  sum += clib_net_to_host_u16 (*((u16 *) data + 6));
228  sum += clib_net_to_host_u16 (*((u16 *) data + 7));
229  n_left -= 8;
230  data += 16;
231  }
232  while (n_left)
233  {
234  sum += clib_net_to_host_u16 (*(u16 *) data);
235  n_left -= 1;
236  data += 2;
237  }
238 #endif
239 
240  sum = (sum & 0xffff) + (sum >> 16);
241  sum = (sum & 0xffff) + (sum >> 16);
242  return ~((u16) sum);
243 }
244 
245 /* Incremental checksum update. */
246 typedef uword ip_csum_t;
247 
250 {
251  ip_csum_t t = sum + x;
252  return t + (t < x);
253 }
254 
255 /* Update checksum changing field at even byte offset from x -> 0. */
258 {
259  ip_csum_t d;
260 
261  d = c - x;
262 
263  /* Fold in carry from high bit. */
264  d -= d > c;
265 
266  ip_csum_t t = ip_csum_with_carry (d, x);
267  ASSERT ((t - c == 0) || (t - c == ~0));
268 
269  return d;
270 }
271 
272 /* Update checksum changing field at even byte offset from 0 -> x. */
275 {
276  return ip_csum_with_carry (c, x);
277 }
278 
281  u32 field_byte_offset, u32 field_n_bytes)
282 {
283  /* For even 1-byte fields on big-endian and odd 1-byte fields on little endian
284  we need to shift byte into place for checksum. */
285  if ((field_n_bytes % 2)
286  && (field_byte_offset % 2) == CLIB_ARCH_IS_LITTLE_ENDIAN)
287  {
288  old = old << 8;
289  new = new << 8;
290  }
291  sum = ip_csum_sub_even (sum, old);
292  sum = ip_csum_add_even (sum, new);
293  return sum;
294 }
295 
296 #define ip_csum_update(sum,old,new,type,field) \
297  ip_csum_update_inline ((sum), (old), (new), \
298  STRUCT_OFFSET_OF (type, field), \
299  STRUCT_SIZE_OF (type, field))
300 
303 {
304  /* Reduce to 16 bits. */
305 #if uword_bits == 64
306  c = (c & (ip_csum_t) 0xffffffff) + (c >> (ip_csum_t) 32);
307  c = (c & 0xffff) + (c >> 16);
308 #endif
309 
310  c = (c & 0xffff) + (c >> 16);
311  c = (c & 0xffff) + (c >> 16);
312 
313  return c;
314 }
315 
317 
318 /* Checksum routine. */
320 ip_incremental_checksum (ip_csum_t sum, void *_data, uword n_bytes)
321 {
322  return (*vnet_incremental_checksum_fp) (sum, _data, n_bytes);
323 }
324 
327 {
328  return ip_csum_fold (sum);
329 }
330 
331 #endif /* included_ip_packet_h */
332 
333 /*
334  * fd.io coding-style-patch-verification: ON
335  *
336  * Local Variables:
337  * eval: (c-set-style "gnu")
338  * End:
339  */
unformat_function_t unformat_ip_dscp
Definition: ip_packet.h:123
#define CLIB_ARCH_IS_LITTLE_ENDIAN
Definition: byte_order.h:45
u8 * format_ip_dscp(u8 *s, va_list *va)
Definition: ip.c:262
enum ip_ecn_t_ ip_ecn_t
uword ip_csum_t
Definition: ip_packet.h:246
static ip_csum_t ip_csum_with_carry(ip_csum_t sum, ip_csum_t x)
Definition: ip_packet.h:249
static_always_inline u16x16 u16x16_mask_last(u16x16 v, u8 n_last)
Definition: vector_avx2.h:189
unsigned char u8
Definition: types.h:56
u8 data[128]
Definition: ipsec_types.api:90
static u16 ip_csum_and_memcpy_fold(ip_csum_t sum, void *dst)
Definition: ip_packet.h:326
#define static_always_inline
Definition: clib.h:109
STATIC_ASSERT_SIZEOF(ip_ecn_t, 1)
ip_dscp_t_
Definition: ip_packet.h:115
static ip_csum_t ip_csum_update_inline(ip_csum_t sum, ip_csum_t old, ip_csum_t new, u32 field_byte_offset, u32 field_n_bytes)
Definition: ip_packet.h:280
unsigned int u32
Definition: types.h:88
enum ip_protocol ip_protocol_t
unsigned short u16
Definition: types.h:57
#define always_inline
Definition: ipsec.h:28
static_always_inline u16x16 u16x16_byte_swap(u16x16 v)
Definition: vector_avx2.h:156
uword() unformat_function_t(unformat_input_t *input, va_list *args)
Definition: format.h:232
static_always_inline u16 ip_csum(void *data, u16 n_left)
Definition: ip_packet.h:155
vl_api_address_t dst
Definition: gre.api:55
svmdb_client_t * c
ip_protocol
Definition: ip_packet.h:47
ip_port_t
Definition: ip_packet.h:55
#define ASSERT(truth)
static_always_inline u32x8 u32x8_hadd(u32x8 v1, u32x8 v2)
Definition: vector_avx2.h:183
enum ip_dscp_t_ ip_dscp_t
static ip_csum_t ip_csum_sub_even(ip_csum_t c, ip_csum_t x)
Definition: ip_packet.h:274
#define foreach_ip_ecn
The set of RFC defined DSCP values.
Definition: ip_packet.h:135
ip_csum_t(* vnet_incremental_checksum_fp)(ip_csum_t, void *, uword)
Definition: ip_checksum.c:124
u64 uword
Definition: types.h:112
#define foreach_ip_builtin_multicast_group
Definition: ip_packet.h:70
u8 * format_ip_ecn(u8 *s, va_list *va)
Definition: ip.c:297
ip_multicast_group_t
Definition: ip_packet.h:81
unsigned long long u32x4
Definition: ixge.c:28
#define foreach_ip_dscp
The set of RFC defined DSCP values.
Definition: ip_packet.h:92
epu16_epi64 u16x16
Definition: vector_avx2.h:123
ip_ecn_t_
Definition: ip_packet.h:141
static ip_csum_t ip_incremental_checksum(ip_csum_t sum, void *_data, uword n_bytes)
Definition: ip_packet.h:320
ip_builtin_protocol_t
Definition: ip_packet.h:63
static u16 ip_csum_fold(ip_csum_t c)
Definition: ip_packet.h:302
static ip_csum_t ip_csum_add_even(ip_csum_t c, ip_csum_t x)
Definition: ip_packet.h:257