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
|
/*
* BIRD -- OSPF
*
* (c) 2000--2004 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*
*/
#ifndef _BIRD_OSPF_RT_H_
#define _BIRD_OSPF_RT_H_
#define ORT_UNDEF -1
#define ORT_ROUTER 1
#define ORT_NET 0
typedef struct orta
{
int type;
u32 options;
/*
* For ORT_ROUTER routes, options field are router-LSA style
* options, with V,E,B bits. In OSPFv2, ASBRs from another areas
* (that we know from rt-summary-lsa) have just ORTA_ASBR in
* options, their real options are unknown.
*/
#define ORTA_ASBR OPT_RT_E
#define ORTA_ABR OPT_RT_B
/*
* For ORT_NET routes, the field is almost unused with one
* exception: ORTA_PREF for external routes means that the route is
* preferred in AS external route selection according to 16.4.1. -
* it is intra-area path using non-backbone area. In other words,
* the forwarding address (or ASBR if forwarding address is zero) is
* intra-area (type == RTS_OSPF) and its area is not a backbone.
*/
#define ORTA_PREF 0x80000000
u32 metric1;
u32 metric2;
u32 tag;
u32 rid; /* Router ID of real advertising router */
struct ospf_area *oa;
struct ospf_area *voa; /* Used when route is replaced in ospf_rt_sum_tr(),
NULL otherwise */
struct mpnh *nhs; /* Next hops computed during SPF */
}
orta;
// struct ospf_iface *ifa; /* Outgoing interface */
// ip_addr nh; /* Next hop */
typedef struct ort
{
/*
* We use fn.x0 to mark persistent rt entries, that are needed for summary
* LSAs that don't have 'proper' rt entry (area networks + default to stubs)
* to keep uid stable (used for LSA ID in OSPFv3 - see fibnode_to_lsaid()).
*
* old_* values are here to represent the last route update. old_rta
* is cached (we keep reference), mainly for multipath nexthops.
* old_rta == NULL means route wasn not in the last update, in that
* case other old_* values are not valid.
*/
struct fib_node fn;
orta n;
u32 old_metric1, old_metric2, old_tag, old_rid;
rta *old_rta;
}
ort;
/*
* Invariants for structs top_hash_entry (nodes of LSA db)
* enforced by SPF calculation for final nodes (color == INSPF):
* - only router, network and AS-external LSAs
* - lsa.age < LSA_MAXAGE
* - dist < LSINFINITY (or 2*LSINFINITY for ext-LSAs)
* - nhs is non-NULL unless the node is oa->rt (calculating router itself)
* - beware, nhs is not valid after SPF calculation
*
* Invariants for structs orta nodes of fib tables po->rtf, oa->rtr:
* - nodes may be invalid (fn.type == 0), in that case other invariants don't hold
* - n.metric1 may be at most a small multiple of LSINFINITY,
* therefore sums do not overflow
* - n.oa is always non-NULL
* - n.nhs is always non-NULL with one exception - configured stubnet
* nodes (in po->rtf).
* - oa->rtr does not contain calculating router itself
*
* There are three types of nexthops in nhs fields:
* - gateway nexthops (non-NULL iface, gw != IPA_NONE)
* - device nexthops (non-NULL iface, gw == IPA_NONE)
* - dummy vlink nexthops (NULL iface, gw == IPA_NONE)
* These three types don't mix, nhs field contains either
* one device, one vlink node, or one/more gateway nodes.
*/
void ospf_rt_spf(struct proto_ospf *po);
void ospf_rt_initort(struct fib_node *fn);
#endif /* _BIRD_OSPF_RT_H_ */
|
