summaryrefslogtreecommitdiffstats
path: root/src/vnet/hash/crc32_5tuple.c
blob: 29d92a96938399d410df1c5bacc0ea6b6bbc5b4d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
/*
 * SPDX-License-Identifier: Apache-2.0
 * Copyright(c) 2021 Cisco Systems, Inc.
 */

#include <vnet/vnet.h>
#include <vnet/ethernet/ethernet.h>
#include <vnet/ip/ip4_packet.h>
#include <vnet/ip/ip6_packet.h>
#include <vnet/ip/ip46_address.h>
#include <vnet/udp/udp_packet.h>
#include <vnet/hash/hash.h>
#include <vppinfra/crc32.h>

typedef union
{
  struct
  {
    ip46_address_t src_address;
    ip46_address_t dst_address;
    union
    {
      struct
      {
	u16 src_port;
	u16 dst_port;
      };
      u32 l4_hdr;
    };
  };
  u8 as_u8[36];
} crc32c_5tuple_key_t;

static const u8 l4_mask_bits[256] = {
  [IP_PROTOCOL_ICMP] = 16,	[IP_PROTOCOL_IGMP] = 8,
  [IP_PROTOCOL_TCP] = 32,	[IP_PROTOCOL_UDP] = 32,
  [IP_PROTOCOL_IPSEC_ESP] = 32, [IP_PROTOCOL_IPSEC_AH] = 32,
  [IP_PROTOCOL_ICMP6] = 16,
};

static_always_inline void
compute_ip6_key (ip6_header_t *ip, crc32c_5tuple_key_t *k)
{
  u8 pr;

  /* copy 32 bytes of ip6 src and dst addresses into hash_key_t */
  clib_memcpy_fast ((u8 *) k, (u8 *) ip + 8, sizeof (ip6_address_t) * 2);
  pr = ip->protocol;
  /* write l4 header */
  k->l4_hdr = *(u32 *) ip6_next_header (ip) & pow2_mask (l4_mask_bits[pr]);
}

static_always_inline void
compute_ip4_key (ip4_header_t *ip, crc32c_5tuple_key_t *k)
{
  u8 pr;
  u64 *key = (u64 *) k;
  /* copy 8 bytes of ip src and dst addresses into hash_key_t */
  key[0] = 0;
  key[1] = 0;
  key[2] = 0;
  key[3] = *(u64 *) ((u8 *) ip + 12);
  pr = ip->protocol;
  /* write l4 header */
  k->l4_hdr = *(u32 *) ip4_next_header (ip) & pow2_mask (l4_mask_bits[pr]);
}
static_always_inline void
compute_ip_key (void *p, crc32c_5tuple_key_t *key)
{
  if ((((u8 *) p)[0] & 0xf0) == 0x40)
    compute_ip4_key (p, key);
  else if ((((u8 *) p)[0] & 0xf0) == 0x60)
    compute_ip6_key (p, key);
}

void
vnet_crc32c_5tuple_ip_func (void **p, u32 *hash, u32 n_packets)
{
  u32 n_left_from = n_packets;

  while (n_left_from >= 8)
    {
      crc32c_5tuple_key_t key[4] = {};

      clib_prefetch_load (p[4]);
      clib_prefetch_load (p[5]);
      clib_prefetch_load (p[6]);
      clib_prefetch_load (p[7]);

      compute_ip_key (p[0], &key[0]);
      compute_ip_key (p[1], &key[1]);
      compute_ip_key (p[2], &key[2]);
      compute_ip_key (p[3], &key[3]);

      hash[0] = clib_crc32c (key[0].as_u8, sizeof (key[0]));
      hash[1] = clib_crc32c (key[1].as_u8, sizeof (key[1]));
      hash[2] = clib_crc32c (key[2].as_u8, sizeof (key[2]));
      hash[3] = clib_crc32c (key[3].as_u8, sizeof (key[3]));

      hash += 4;
      n_left_from -= 4;
      p += 4;
    }

  while (n_left_from > 0)
    {
      crc32c_5tuple_key_t key = {};

      compute_ip_key (p[0], &key);

      hash[0] = clib_crc32c (key.as_u8, sizeof (key));

      hash += 1;
      n_left_from -= 1;
      p += 1;
    }
}

static_always_inline void
compute_ethernet_key (void *p, crc32c_5tuple_key_t *key)
{
  u16 ethertype = 0, l2hdr_sz = 0;

  ethernet_header_t *eh = (ethernet_header_t *) p;
  ethertype = clib_net_to_host_u16 (eh->type);
  l2hdr_sz = sizeof (ethernet_header_t);

  if (ethernet_frame_is_tagged (ethertype))
    {
      ethernet_vlan_header_t *vlan = (ethernet_vlan_header_t *) (eh + 1);

      ethertype = clib_net_to_host_u16 (vlan->type);
      l2hdr_sz += sizeof (*vlan);
      while (ethernet_frame_is_tagged (ethertype))
	{
	  vlan++;
	  ethertype = clib_net_to_host_u16 (vlan->type);
	  l2hdr_sz += sizeof (*vlan);
	}
    }

  if (ethertype == ETHERNET_TYPE_IP4)
    {
      ip4_header_t *ip4 = (ip4_header_t *) (p + l2hdr_sz);
      compute_ip4_key (ip4, key);
    }
  else if (ethertype == ETHERNET_TYPE_IP6)
    {
      ip6_header_t *ip6 = (ip6_header_t *) (p + l2hdr_sz);
      compute_ip6_key (ip6, key);
    }
}

void
vnet_crc32c_5tuple_ethernet_func (void **p, u32 *hash, u32 n_packets)
{
  u32 n_left_from = n_packets;

  while (n_left_from >= 8)
    {
      crc32c_5tuple_key_t key[4] = {};

      clib_prefetch_load (p[4]);
      clib_prefetch_load (p[5]);
      clib_prefetch_load (p[6]);
      clib_prefetch_load (p[7]);

      compute_ethernet_key (p[0], &key[0]);
      compute_ethernet_key (p[1], &key[1]);
      compute_ethernet_key (p[2], &key[2]);
      compute_ethernet_key (p[3], &key[3]);

      hash[0] = clib_crc32c (key[0].as_u8, sizeof (key[0]));
      hash[1] = clib_crc32c (key[1].as_u8, sizeof (key[1]));
      hash[2] = clib_crc32c (key[2].as_u8, sizeof (key[2]));
      hash[3] = clib_crc32c (key[3].as_u8, sizeof (key[3]));

      hash += 4;
      n_left_from -= 4;
      p += 4;
    }

  while (n_left_from > 0)
    {
      crc32c_5tuple_key_t key = {};

      compute_ethernet_key (p[0], &key);

      hash[0] = clib_crc32c (key.as_u8, sizeof (key));

      hash += 1;
      n_left_from -= 1;
      p += 1;
    }
}

VNET_REGISTER_HASH_FUNCTION (crc32c_5tuple, static) = {
  .name = "crc32c-5tuple",
  .description = "IPv4/IPv6 header and TCP/UDP ports",
  .priority = 50,
  .function[VNET_HASH_FN_TYPE_ETHERNET] = vnet_crc32c_5tuple_ethernet_func,
  .function[VNET_HASH_FN_TYPE_IP] = vnet_crc32c_5tuple_ip_func,
};