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 #ifndef __MPLS_LOOKUP_H__
17 #define __MPLS_LOOKUP_H__
19 #include <vnet/mpls/mpls.h>
20 #include <vnet/ip/ip.h>
21 #include <vnet/bier/bier_fwd.h>
22 #include <vnet/ip/ip4_inlines.h>
23 #include <vnet/ip/ip6_inlines.h>
26 * The arc/edge from the MPLS lookup node to the MPLS replicate node
28 extern u32 mpls_lookup_to_replicate_edge;
31 * Enum of statically configred MPLS lookup next nodes
33 typedef enum mpls_lookup_next_t_
35 MPLS_LOOKUP_NEXT_DROP = 0,
40 * We'll use it to select which adjacency to use for this flow. And other things.
43 mpls_compute_flow_hash (const mpls_unicast_header_t * hdr,
44 flow_hash_config_t flow_hash_config)
47 * We need to byte swap so we use the numerical value. i.e. an odd label
48 * leads to an odd bucket. as opposed to a label above and below value X.
50 u8 next_label_is_entropy;
51 mpls_label_t ho_label;
54 ho_label = clib_net_to_host_u32(hdr->label_exp_s_ttl);
55 hash = vnet_mpls_uc_get_label(ho_label);
56 hash ^= ip_flow_hash_router_id;
57 next_label_is_entropy = 0;
59 while (MPLS_EOS != vnet_mpls_uc_get_s(ho_label))
62 ho_label = clib_net_to_host_u32(hdr->label_exp_s_ttl);
63 value = vnet_mpls_uc_get_label(ho_label);
65 if (1 == next_label_is_entropy)
68 * The label is an entropy value, use it alone as the hash
72 if (MPLS_IETF_ENTROPY_LABEL == value)
75 * we've met a label in the stack indicating that tha next
76 * label is an entropy value
78 next_label_is_entropy = 1;
83 * XOR the label values in the stack together to
84 * build up the hash value
91 * check the top nibble for v4 and v6
95 switch (((u8*)hdr)[0] >> 4)
98 /* incorporate the v4 flow-hash */
100 ip4_compute_flow_hash ((const ip4_header_t *) hdr, flow_hash_config);
103 /* incorporate the v6 flow-hash */
105 ip6_compute_flow_hash ((const ip6_header_t *) hdr, flow_hash_config);
108 /* incorporate the bier flow-hash */
109 hash ^= bier_compute_flow_hash ((const bier_hdr_t *)hdr);
118 #endif /* __MPLS_LOOKUP_H__ */