FD.io VPP  v21.01.1
Vector Packet Processing
ip6_inlines.h
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1 /*
2  * Copyright (c) 2016 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/ip6.h: ip6 main include file
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_ip6_inlines_h
41 #define included_ip_ip6_inlines_h
42 
43 #include <vnet/ip/ip6_packet.h>
45 
46 /* Compute flow hash. We'll use it to select which Sponge to use for this
47  flow. And other things. */
50  flow_hash_config_t flow_hash_config)
51 {
52  tcp_header_t *tcp;
53  u64 a, b, c;
54  u64 t1, t2;
55  uword is_tcp_udp = 0;
56  u8 protocol = ip->protocol;
57 
58  if (PREDICT_TRUE
59  ((ip->protocol == IP_PROTOCOL_TCP)
60  || (ip->protocol == IP_PROTOCOL_UDP)))
61  {
62  is_tcp_udp = 1;
63  tcp = (void *) (ip + 1);
64  }
65  else if (ip->protocol == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS)
66  {
68  if ((hbh->protocol == IP_PROTOCOL_TCP) ||
69  (hbh->protocol == IP_PROTOCOL_UDP))
70  {
71  is_tcp_udp = 1;
72  tcp = (tcp_header_t *) ((u8 *) hbh + ((hbh->length + 1) << 3));
73  }
74  protocol = hbh->protocol;
75  }
76 
77  t1 = (ip->src_address.as_u64[0] ^ ip->src_address.as_u64[1]);
78  t1 = (flow_hash_config & IP_FLOW_HASH_SRC_ADDR) ? t1 : 0;
79 
80  t2 = (ip->dst_address.as_u64[0] ^ ip->dst_address.as_u64[1]);
81  t2 = (flow_hash_config & IP_FLOW_HASH_DST_ADDR) ? t2 : 0;
82 
83  a = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ? t2 : t1;
84  b = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ? t1 : t2;
85 
86  t1 = is_tcp_udp ? tcp->src : 0;
87  t2 = is_tcp_udp ? tcp->dst : 0;
88 
89  t1 = (flow_hash_config & IP_FLOW_HASH_SRC_PORT) ? t1 : 0;
90  t2 = (flow_hash_config & IP_FLOW_HASH_DST_PORT) ? t2 : 0;
91 
92  if (flow_hash_config & IP_FLOW_HASH_SYMMETRIC)
93  {
94  if (b < a)
95  {
96  c = a;
97  a = b;
98  b = c;
99  }
100  if (t2 < t1)
101  {
102  t2 += t1;
103  t1 = t2 - t1;
104  t2 = t2 - t1;
105  }
106  }
107 
108  b ^= (flow_hash_config & IP_FLOW_HASH_PROTO) ? protocol : 0;
109  c = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ?
110  ((t1 << 16) | t2) : ((t2 << 16) | t1);
111 
112  hash_mix64 (a, b, c);
113  return (u32) c;
114 }
115 
116 /* ip6_locate_header
117  *
118  * This function is to search for the header specified by the protocol number
119  * in find_hdr_type.
120  * This is used to locate a specific IPv6 extension header
121  * or to find transport layer header.
122  * 1. If the find_hdr_type < 0 then it finds and returns the protocol number and
123  * offset stored in *offset of the transport or ESP header in the chain if
124  * found.
125  * 2. If a header with find_hdr_type > 0 protocol number is found then the
126  * offset is stored in *offset and protocol number of the header is
127  * returned.
128  * 3. If find_hdr_type is not found or packet is malformed or
129  * it is a non-first fragment -1 is returned.
130  */
131 always_inline int
133  ip6_header_t * ip0, int find_hdr_type, u32 * offset)
134 {
135  u8 next_proto = ip0->protocol;
136  u8 *next_header;
137  u8 done = 0;
138  u32 cur_offset;
139  u8 *temp_nxthdr = 0;
140  u32 exthdr_len = 0;
141 
142  next_header = ip6_next_header (ip0);
143  cur_offset = sizeof (ip6_header_t);
144  while (1)
145  {
146  done = (next_proto == find_hdr_type);
147  if (PREDICT_FALSE
148  (next_header >=
149  (u8 *) vlib_buffer_get_current (p0) + p0->current_length))
150  {
151  //A malicious packet could set an extension header with a too big size
152  return (-1);
153  }
154  if (done)
155  break;
156  if ((!ip6_ext_hdr (next_proto)) || next_proto == IP_PROTOCOL_IP6_NONXT)
157  {
158  if (find_hdr_type < 0)
159  break;
160  return -1;
161  }
162  if (next_proto == IP_PROTOCOL_IPV6_FRAGMENTATION)
163  {
164  ip6_frag_hdr_t *frag_hdr = (ip6_frag_hdr_t *) next_header;
165  u16 frag_off = ip6_frag_hdr_offset (frag_hdr);
166  /* Non first fragment return -1 */
167  if (frag_off)
168  return (-1);
169  exthdr_len = sizeof (ip6_frag_hdr_t);
170  temp_nxthdr = next_header + exthdr_len;
171  }
172  else if (next_proto == IP_PROTOCOL_IPSEC_AH)
173  {
174  exthdr_len =
175  ip6_ext_authhdr_len (((ip6_ext_header_t *) next_header));
176  temp_nxthdr = next_header + exthdr_len;
177  }
178  else
179  {
180  exthdr_len =
181  ip6_ext_header_len (((ip6_ext_header_t *) next_header));
182  temp_nxthdr = next_header + exthdr_len;
183  }
184  next_proto = ((ip6_ext_header_t *) next_header)->next_hdr;
185  next_header = temp_nxthdr;
186  cur_offset += exthdr_len;
187  }
188 
189  *offset = cur_offset;
190  return (next_proto);
191 }
192 
193 
194 /**
195  * Push IPv6 header to buffer
196  *
197  * @param vm - vlib_main
198  * @param b - buffer to write the header to
199  * @param src - source IP
200  * @param dst - destination IP
201  * @param prot - payload proto
202  * @param flow_label - flow label
203  *
204  * @return - pointer to start of IP header
205  */
206 always_inline void *
208  ip6_address_t * src, ip6_address_t * dst,
209  int proto, u32 flow_label)
210 {
211  ip6_header_t *ip6h;
212  u16 payload_length;
213 
214  /* make some room */
215  ip6h = vlib_buffer_push_uninit (b, sizeof (ip6_header_t));
216  ASSERT (flow_label < 1 << 20);
218  clib_host_to_net_u32 ((0x6 << 28) | flow_label);
219 
220  /* calculate ip6 payload length */
221  payload_length = vlib_buffer_length_in_chain (vm, b);
222  payload_length -= sizeof (*ip6h);
223 
224  ip6h->payload_length = clib_host_to_net_u16 (payload_length);
225 
226  ip6h->hop_limit = 0xff;
227  ip6h->protocol = proto;
228  clib_memcpy_fast (ip6h->src_address.as_u8, src->as_u8,
229  sizeof (ip6h->src_address));
230  clib_memcpy_fast (ip6h->dst_address.as_u8, dst->as_u8,
231  sizeof (ip6h->src_address));
232  vnet_buffer (b)->l3_hdr_offset = (u8 *) ip6h - b->data;
233  b->flags |= VNET_BUFFER_F_IS_IP6 | VNET_BUFFER_F_L3_HDR_OFFSET_VALID;
234 
235  return ip6h;
236 }
237 
238 /**
239  * Push IPv6 header to buffer
240  *
241  * @param vm - vlib_main
242  * @param b - buffer to write the header to
243  * @param src - source IP
244  * @param dst - destination IP
245  * @param prot - payload proto
246  *
247  * @return - pointer to start of IP header
248  */
249 always_inline void *
251  ip6_address_t * src, ip6_address_t * dst, int proto)
252 {
253  return vlib_buffer_push_ip6_custom (vm, b, src, dst, proto,
254  0 /* flow label */ );
255 
256 }
257 
258 #endif /* included_ip_ip6_h */
259 
260 /*
261  * fd.io coding-style-patch-verification: ON
262  *
263  * Local Variables:
264  * eval: (c-set-style "gnu")
265  * End:
266  */
u32 flags
buffer flags: VLIB_BUFFER_FREE_LIST_INDEX_MASK: bits used to store free list index, VLIB_BUFFER_IS_TRACED: trace this buffer.
Definition: buffer.h:124
#define IP_FLOW_HASH_SYMMETRIC
Definition: ip_flow_hash.h:26
a
Definition: bitmap.h:544
#define PREDICT_TRUE(x)
Definition: clib.h:122
unsigned long u64
Definition: types.h:89
vl_api_ip_proto_t protocol
Definition: lb_types.api:72
#define clib_memcpy_fast(a, b, c)
Definition: string.h:81
u16 current_length
Nbytes between current data and the end of this buffer.
Definition: buffer.h:113
vl_api_address_t src
Definition: gre.api:54
vlib_main_t * vm
Definition: in2out_ed.c:1580
static void * vlib_buffer_push_ip6_custom(vlib_main_t *vm, vlib_buffer_t *b, ip6_address_t *src, ip6_address_t *dst, int proto, u32 flow_label)
Push IPv6 header to buffer.
Definition: ip6_inlines.h:207
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:402
#define IP_FLOW_HASH_SRC_PORT
Definition: ip_flow_hash.h:23
struct _tcp_header tcp_header_t
ip6_address_t src_address
Definition: ip6_packet.h:310
unsigned char u8
Definition: types.h:56
const cJSON *const b
Definition: cJSON.h:255
unsigned int u32
Definition: types.h:88
static void * vlib_buffer_push_ip6(vlib_main_t *vm, vlib_buffer_t *b, ip6_address_t *src, ip6_address_t *dst, int proto)
Push IPv6 header to buffer.
Definition: ip6_inlines.h:250
#define IP_FLOW_HASH_DST_ADDR
Definition: ip_flow_hash.h:21
vl_api_ip_proto_t proto
Definition: acl_types.api:51
unsigned short u16
Definition: types.h:57
static void * vlib_buffer_get_current(vlib_buffer_t *b)
Get pointer to current data to process.
Definition: buffer.h:233
#define IP_FLOW_HASH_DST_PORT
Definition: ip_flow_hash.h:24
#define PREDICT_FALSE(x)
Definition: clib.h:121
#define always_inline
Definition: ipsec.h:28
vl_api_address_t dst
Definition: gre.api:55
#define ip6_ext_authhdr_len(p)
Definition: ip6_packet.h:515
#define ip6_ext_header_len(p)
Definition: ip6_packet.h:514
#define hash_mix64(a0, b0, c0)
Definition: hash.h:531
svmdb_client_t * c
u8 data[]
Packet data.
Definition: buffer.h:181
#define IP_FLOW_HASH_PROTO
Definition: ip_flow_hash.h:22
static void * ip6_next_header(ip6_header_t *i)
Definition: ip6_packet.h:376
static u8 ip6_ext_hdr(u8 nexthdr)
Definition: ip6_packet.h:493
#define ip6_frag_hdr_offset(hdr)
Definition: ip6_packet.h:669
#define ASSERT(truth)
static u32 ip6_compute_flow_hash(const ip6_header_t *ip, flow_hash_config_t flow_hash_config)
Definition: ip6_inlines.h:49
template key/value backing page structure
Definition: bihash_doc.h:44
u32 ip_version_traffic_class_and_flow_label
Definition: ip6_packet.h:297
static void * vlib_buffer_push_uninit(vlib_buffer_t *b, u8 size)
Prepend uninitialized data to buffer.
Definition: buffer.h:339
u16 payload_length
Definition: ip6_packet.h:301
vl_api_address_t ip
Definition: l2.api:501
#define IP_FLOW_HASH_REVERSE_SRC_DST
Definition: ip_flow_hash.h:25
VLIB buffer representation.
Definition: buffer.h:102
u64 uword
Definition: types.h:112
#define IP_FLOW_HASH_SRC_ADDR
Flow hash configuration.
Definition: ip_flow_hash.h:20
#define vnet_buffer(b)
Definition: buffer.h:417
u32 flow_hash_config_t
A flow hash configuration is a mask of the flow hash options.
Definition: ip_flow_hash.h:43
static int ip6_locate_header(vlib_buffer_t *p0, ip6_header_t *ip0, int find_hdr_type, u32 *offset)
Definition: ip6_inlines.h:132
ip6_address_t dst_address
Definition: ip6_packet.h:310