FD.io VPP  v20.05.1-6-gf53edbc3b
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 
46 typedef enum ip_protocol
47 {
48 #define ip_protocol(n,s) IP_PROTOCOL_##s = n,
49 #include "protocols.def"
50 #undef ip_protocol
51 } __clib_packed ip_protocol_t;
52 
53 /* TCP/UDP ports. */
54 typedef enum
55 {
56 #define ip_port(s,n) IP_PORT_##s = n,
57 #include "ports.def"
58 #undef ip_port
59 } ip_port_t;
60 
61 /* Classifies protocols into UDP, ICMP or other. */
62 typedef enum
63 {
68 
69 #define foreach_ip_builtin_multicast_group \
70  _ (1, all_hosts_on_subnet) \
71  _ (2, all_routers_on_subnet) \
72  _ (4, dvmrp) \
73  _ (5, ospf_all_routers) \
74  _ (6, ospf_designated_routers) \
75  _ (13, pim) \
76  _ (18, vrrp) \
77  _ (102, hsrp) \
78  _ (22, igmp_v3)
79 
80 typedef enum
81 {
82 #define _(n,f) IP_MULTICAST_GROUP_##f = n,
84 #undef _
86 
87 
88 /**
89  * The set of RFC defined DSCP values.
90  */
91 #define foreach_ip_dscp \
92  _(0, CS0) \
93  _(8, CS1) \
94  _(10, AF11) \
95  _(12, AF12) \
96  _(14, AF13) \
97  _(16, CS2) \
98  _(18, AF21) \
99  _(20, AF22) \
100  _(22, AF23) \
101  _(24, CS3) \
102  _(26, AF31) \
103  _(28, AF32) \
104  _(30, AF33) \
105  _(32, CS4) \
106  _(34, AF41) \
107  _(36, AF42) \
108  _(38, AF43) \
109  _(40, CS5) \
110  _(46, EF) \
111  _(48, CS6) \
112  _(50, CS7)
113 
114 typedef enum ip_dscp_t_
115 {
116 #define _(n,f) IP_DSCP_##f = n,
118 #undef _
119 } __clib_packed ip_dscp_t;
120 
121 extern u8 *format_ip_dscp (u8 * s, va_list * va);
122 
123 /**
124  * IP DSCP bit shift
125  * The ECN occupies the 2 least significant bits of the TC field
126  */
127 #define IP_PACKET_TC_FIELD_DSCP_BIT_SHIFT 2
128 #define IP_PACKET_TC_FIELD_ECN_MASK 0x03
129 
130 /**
131  * The set of RFC defined DSCP values.
132  */
133 #define foreach_ip_ecn \
134  _(0, NON_ECN) \
135  _(1, ECT_0) \
136  _(2, ECT_1) \
137  _(3, CE)
138 
139 typedef enum ip_ecn_t_
140 {
141 #define _(n,f) IP_ECN_##f = n,
143 #undef _
144 } __clib_packed ip_ecn_t;
145 
147 
148 extern u8 *format_ip_ecn (u8 * s, va_list * va);
149 
150 /* IP checksum support. */
151 
153 ip_csum (void *data, u16 n_left)
154 {
155  u32 sum;
156 #ifdef CLIB_HAVE_VEC256
157  u16x16 v1, v2;
158  u32x8 zero = { 0 };
159  u32x8 sum8 = { 0 };
160  u32x4 sum4;
161 #endif
162 
163  /* if there is odd number of bytes, pad by zero and store in sum */
164  sum = (n_left & 1) ? ((u8 *) data)[n_left - 1] << 8 : 0;
165 
166  /* we deal with words */
167  n_left >>= 1;
168 
169 #ifdef CLIB_HAVE_VEC256
170  while (n_left >= 32)
171  {
172  v1 = u16x16_load_unaligned (data);
173  v2 = u16x16_load_unaligned (data + 32);
174 
175 #ifdef CLIB_ARCH_IS_LITTLE_ENDIAN
176  v1 = u16x16_byte_swap (v1);
177  v2 = u16x16_byte_swap (v2);
178 #endif
179  sum8 += u16x8_extend_to_u32x8 (u16x16_extract_lo (v1));
180  sum8 += u16x8_extend_to_u32x8 (u16x16_extract_hi (v1));
181  sum8 += u16x8_extend_to_u32x8 (u16x16_extract_lo (v2));
182  sum8 += u16x8_extend_to_u32x8 (u16x16_extract_hi (v2));
183  n_left -= 32;
184  data += 64;
185  }
186 
187  if (n_left >= 16)
188  {
189  v1 = u16x16_load_unaligned (data);
190 #ifdef CLIB_ARCH_IS_LITTLE_ENDIAN
191  v1 = u16x16_byte_swap (v1);
192 #endif
193  v1 = u16x16_byte_swap (u16x16_load_unaligned (data));
194  sum8 += u16x8_extend_to_u32x8 (u16x16_extract_lo (v1));
195  sum8 += u16x8_extend_to_u32x8 (u16x16_extract_hi (v1));
196  n_left -= 16;
197  data += 32;
198  }
199 
200  if (n_left)
201  {
202  v1 = u16x16_load_unaligned (data);
203 #ifdef CLIB_ARCH_IS_LITTLE_ENDIAN
204  v1 = u16x16_byte_swap (v1);
205 #endif
206  v1 = u16x16_mask_last (v1, 16 - n_left);
207  sum8 += u16x8_extend_to_u32x8 (u16x16_extract_lo (v1));
208  sum8 += u16x8_extend_to_u32x8 (u16x16_extract_hi (v1));
209  }
210 
211  sum8 = u32x8_hadd (sum8, zero);
212  sum4 = u32x8_extract_lo (sum8) + u32x8_extract_hi (sum8);
213  sum = sum4[0] + sum4[1];
214 
215 #else
216  /* scalar version */
217  while (n_left >= 8)
218  {
219  sum += clib_net_to_host_u16 (*((u16 *) data + 0));
220  sum += clib_net_to_host_u16 (*((u16 *) data + 1));
221  sum += clib_net_to_host_u16 (*((u16 *) data + 2));
222  sum += clib_net_to_host_u16 (*((u16 *) data + 3));
223  sum += clib_net_to_host_u16 (*((u16 *) data + 4));
224  sum += clib_net_to_host_u16 (*((u16 *) data + 5));
225  sum += clib_net_to_host_u16 (*((u16 *) data + 6));
226  sum += clib_net_to_host_u16 (*((u16 *) data + 7));
227  n_left -= 8;
228  data += 16;
229  }
230  while (n_left)
231  {
232  sum += clib_net_to_host_u16 (*(u16 *) data);
233  n_left -= 1;
234  data += 2;
235  }
236 #endif
237 
238  sum = (sum & 0xffff) + (sum >> 16);
239  sum = (sum & 0xffff) + (sum >> 16);
240  return ~((u16) sum);
241 }
242 
243 /* Incremental checksum update. */
244 typedef uword ip_csum_t;
245 
248 {
249  ip_csum_t t = sum + x;
250  return t + (t < x);
251 }
252 
253 /* Update checksum changing field at even byte offset from x -> 0. */
256 {
257  ip_csum_t d;
258 
259  d = c - x;
260 
261  /* Fold in carry from high bit. */
262  d -= d > c;
263 
264  ip_csum_t t = ip_csum_with_carry (d, x);
265  ASSERT ((t - c == 0) || (t - c == ~0));
266 
267  return d;
268 }
269 
270 /* Update checksum changing field at even byte offset from 0 -> x. */
273 {
274  return ip_csum_with_carry (c, x);
275 }
276 
279  u32 field_byte_offset, u32 field_n_bytes)
280 {
281  /* For even 1-byte fields on big-endian and odd 1-byte fields on little endian
282  we need to shift byte into place for checksum. */
283  if ((field_n_bytes % 2)
284  && (field_byte_offset % 2) == CLIB_ARCH_IS_LITTLE_ENDIAN)
285  {
286  old = old << 8;
287  new = new << 8;
288  }
289  sum = ip_csum_sub_even (sum, old);
290  sum = ip_csum_add_even (sum, new);
291  return sum;
292 }
293 
294 #define ip_csum_update(sum,old,new,type,field) \
295  ip_csum_update_inline ((sum), (old), (new), \
296  STRUCT_OFFSET_OF (type, field), \
297  STRUCT_SIZE_OF (type, field))
298 
301 {
302  /* Reduce to 16 bits. */
303 #if uword_bits == 64
304  c = (c & (ip_csum_t) 0xffffffff) + (c >> (ip_csum_t) 32);
305  c = (c & 0xffff) + (c >> 16);
306 #endif
307 
308  c = (c & 0xffff) + (c >> 16);
309  c = (c & 0xffff) + (c >> 16);
310 
311  return c;
312 }
313 
315 
316 /* Checksum routine. */
318 ip_incremental_checksum (ip_csum_t sum, void *_data, uword n_bytes)
319 {
320  return (*vnet_incremental_checksum_fp) (sum, _data, n_bytes);
321 }
322 
325 {
326  return ip_csum_fold (sum);
327 }
328 
329 #endif /* included_ip_packet_h */
330 
331 /*
332  * fd.io coding-style-patch-verification: ON
333  *
334  * Local Variables:
335  * eval: (c-set-style "gnu")
336  * End:
337  */
#define CLIB_ARCH_IS_LITTLE_ENDIAN
Definition: byte_order.h:45
u8 * format_ip_dscp(u8 *s, va_list *va)
Definition: ip.c:136
enum ip_ecn_t_ ip_ecn_t
uword ip_csum_t
Definition: ip_packet.h:244
static ip_csum_t ip_csum_with_carry(ip_csum_t sum, ip_csum_t x)
Definition: ip_packet.h:247
static_always_inline u16x16 u16x16_mask_last(u16x16 v, u8 n_last)
Definition: vector_avx2.h:172
unsigned char u8
Definition: types.h:56
static u16 ip_csum_and_memcpy_fold(ip_csum_t sum, void *dst)
Definition: ip_packet.h:324
#define static_always_inline
Definition: clib.h:106
STATIC_ASSERT_SIZEOF(ip_ecn_t, 1)
ip_dscp_t_
Definition: ip_packet.h:114
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:278
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
static_always_inline u16 ip_csum(void *data, u16 n_left)
Definition: ip_packet.h:153
vl_api_address_t dst
Definition: gre.api:55
svmdb_client_t * c
ip_protocol
Definition: ip_packet.h:46
ip_port_t
Definition: ip_packet.h:54
#define ASSERT(truth)
static_always_inline u32x8 u32x8_hadd(u32x8 v1, u32x8 v2)
Definition: vector_avx2.h:166
u8 data[128]
Definition: ipsec_types.api:89
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:272
#define foreach_ip_ecn
The set of RFC defined DSCP values.
Definition: ip_packet.h:133
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:69
u8 * format_ip_ecn(u8 *s, va_list *va)
Definition: ip.c:153
ip_multicast_group_t
Definition: ip_packet.h:80
unsigned long long u32x4
Definition: ixge.c:28
#define foreach_ip_dscp
The set of RFC defined DSCP values.
Definition: ip_packet.h:91
epu16_epi64 u16x16
Definition: vector_avx2.h:123
ip_ecn_t_
Definition: ip_packet.h:139
static ip_csum_t ip_incremental_checksum(ip_csum_t sum, void *_data, uword n_bytes)
Definition: ip_packet.h:318
ip_builtin_protocol_t
Definition: ip_packet.h:62
static u16 ip_csum_fold(ip_csum_t c)
Definition: ip_packet.h:300
static ip_csum_t ip_csum_add_even(ip_csum_t c, ip_csum_t x)
Definition: ip_packet.h:255