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:
7 * http://www.apache.org/licenses/LICENSE-2.0
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.
16 * ip/ip_packet.h: packet format common between ip4 & ip6
18 * Copyright (c) 2008 Eliot Dresselhaus
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:
28 * The above copyright notice and this permission notice shall be
29 * included in all copies or substantial portions of the Software.
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.
40 #ifndef included_ip_packet_h
41 #define included_ip_packet_h
43 #include <vppinfra/byte_order.h>
44 #include <vppinfra/error.h>
46 typedef enum ip_protocol
48 #define ip_protocol(n,s) IP_PROTOCOL_##s = n,
49 #include "protocols.def"
56 #define ip_port(s,n) IP_PORT_##s = n,
61 /* Classifies protocols into UDP, ICMP or other. */
64 IP_BUILTIN_PROTOCOL_UDP,
65 IP_BUILTIN_PROTOCOL_ICMP,
66 IP_BUILTIN_PROTOCOL_UNKNOWN,
67 } ip_builtin_protocol_t;
69 #define foreach_ip_builtin_multicast_group \
70 _ (1, all_hosts_on_subnet) \
71 _ (2, all_routers_on_subnet) \
73 _ (5, ospf_all_routers) \
74 _ (6, ospf_designated_routers) \
82 #define _(n,f) IP_MULTICAST_GROUP_##f = n,
83 foreach_ip_builtin_multicast_group
85 } ip_multicast_group_t;
87 /* IP checksum support. */
89 /* Incremental checksum update. */
90 typedef uword ip_csum_t;
92 always_inline ip_csum_t
93 ip_csum_with_carry (ip_csum_t sum, ip_csum_t x)
95 ip_csum_t t = sum + x;
99 /* Update checksum changing field at even byte offset from x -> 0. */
100 always_inline ip_csum_t
101 ip_csum_add_even (ip_csum_t c, ip_csum_t x)
107 /* Fold in carry from high bit. */
110 ASSERT (ip_csum_with_carry (d, x) == c);
115 /* Update checksum changing field at even byte offset from 0 -> x. */
116 always_inline ip_csum_t
117 ip_csum_sub_even (ip_csum_t c, ip_csum_t x)
119 return ip_csum_with_carry (c, x);
122 always_inline ip_csum_t
123 ip_csum_update_inline (ip_csum_t sum, ip_csum_t old, ip_csum_t new,
124 u32 field_byte_offset, u32 field_n_bytes)
126 /* For even 1-byte fields on big-endian and odd 1-byte fields on little endian
127 we need to shift byte into place for checksum. */
128 if ((field_n_bytes % 2)
129 && (field_byte_offset % 2) == CLIB_ARCH_IS_LITTLE_ENDIAN)
134 sum = ip_csum_sub_even (sum, old);
135 sum = ip_csum_add_even (sum, new);
139 #define ip_csum_update(sum,old,new,type,field) \
140 ip_csum_update_inline ((sum), (old), (new), \
141 STRUCT_OFFSET_OF (type, field), \
142 STRUCT_SIZE_OF (type, field))
145 ip_csum_fold (ip_csum_t c)
147 /* Reduce to 16 bits. */
149 c = (c & (ip_csum_t) 0xffffffff) + (c >> (ip_csum_t) 32);
150 c = (c & 0xffff) + (c >> 16);
153 c = (c & 0xffff) + (c >> 16);
154 c = (c & 0xffff) + (c >> 16);
159 /* Copy data and checksum at the same time. */
160 ip_csum_t ip_csum_and_memcpy (ip_csum_t sum, void *dst, void *src,
164 ip_csum_and_memcpy_fold (ip_csum_t sum, void *dst)
166 return ip_csum_fold (sum);
169 /* Checksum routine. */
170 ip_csum_t ip_incremental_checksum (ip_csum_t sum, void *data, uword n_bytes);
172 #endif /* included_ip_packet_h */
175 * fd.io coding-style-patch-verification: ON
178 * eval: (c-set-style "gnu")