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
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
|
/*
* BIRD -- Table-to-Table Routing Protocol a.k.a Pipe
*
* (c) 1999--2000 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
/**
* DOC: Pipe
*
* The Pipe protocol is very simple. It just connects to two routing tables
* using proto_add_announce_hook() and whenever it receives a rt_notify()
* about a change in one of the tables, it converts it to a rte_update()
* in the other one.
*
* To avoid pipe loops, Pipe keeps a `being updated' flag in each routing
* table.
*/
#undef LOCAL_DEBUG
#include "nest/bird.h"
#include "nest/iface.h"
#include "nest/protocol.h"
#include "nest/route.h"
#include "conf/conf.h"
#include "filter/filter.h"
#include "lib/string.h"
#include "pipe.h"
static void
pipe_send(struct pipe_proto *p, rtable *src_table, rtable *dest, net *n, rte *new, rte *old, ea_list *attrs)
{
struct proto *src;
net *nn;
rte *e;
rta a;
if (!new && !old)
return;
if (dest->pipe_busy)
{
log(L_ERR "Pipe loop detected when sending %I/%d to table %s",
n->n.prefix, n->n.pxlen, dest->name);
return;
}
nn = net_get(dest, n->n.prefix, n->n.pxlen);
if (new)
{
memcpy(&a, new->attrs, sizeof(rta));
if (p->mode == PIPE_OPAQUE)
{
a.proto = &p->p;
a.source = RTS_PIPE;
}
a.aflags = 0;
a.eattrs = attrs;
e = rte_get_temp(&a);
e->net = nn;
e->pflags = 0;
if (p->mode == PIPE_TRANSPARENT)
{
/* Copy protocol specific embedded attributes. */
memcpy(&(e->u), &(new->u), sizeof(e->u));
e->pref = new->pref;
e->pflags = new->pflags;
}
src = new->attrs->proto;
}
else
{
e = NULL;
src = old->attrs->proto;
}
src_table->pipe_busy = 1;
rte_update(dest, nn, &p->p, (p->mode == PIPE_OPAQUE) ? &p->p : src, e);
src_table->pipe_busy = 0;
}
static void
pipe_rt_notify_pri(struct proto *P, net *net, rte *new, rte *old, ea_list *attrs)
{
struct pipe_proto *p = (struct pipe_proto *) P;
DBG("PIPE %c> %I/%d\n", (new ? '+' : '-'), net->n.prefix, net->n.pxlen);
pipe_send(p, p->p.table, p->peer, net, new, old, attrs);
}
static void
pipe_rt_notify_sec(struct proto *P, net *net, rte *new, rte *old, ea_list *attrs)
{
struct pipe_proto *p = ((struct pipe_proto *) P)->phantom;
DBG("PIPE %c< %I/%d\n", (new ? '+' : '-'), net->n.prefix, net->n.pxlen);
pipe_send(p, p->peer, p->p.table, net, new, old, attrs);
}
static int
pipe_import_control(struct proto *P, rte **ee, ea_list **ea UNUSED, struct linpool *p UNUSED)
{
struct proto *pp = (*ee)->sender;
if (pp == P || pp == &((struct pipe_proto *) P)->phantom->p)
return -1; /* Avoid local loops automatically */
return 0;
}
static int
pipe_reload_routes(struct proto *P)
{
/*
* Because the pipe protocol feeds routes from both routing tables
* together, both directions are reloaded during refeed and 'reload
* out' command works like 'reload' command. For symmetry, we also
* request refeed when 'reload in' command is used.
*/
proto_request_feeding(P);
return 1;
}
static int
pipe_start(struct proto *P)
{
struct pipe_proto *p = (struct pipe_proto *) P;
struct pipe_proto *ph;
struct announce_hook *a;
/*
* Create a phantom protocol which will represent the remote
* end of the pipe (we need to do this in order to get different
* filters and announce functions and it unfortunately involves
* a couple of magic trickery).
*
* The phantom protocol is used ONLY in announce hooks and
* therefore in do_rte_announce() function.
*/
ph = mb_alloc(P->pool, sizeof(struct pipe_proto));
memcpy(ph, p, sizeof(struct pipe_proto));
p->phantom = ph;
ph->phantom = p;
ph->p.accept_ra_types = (p->mode == PIPE_OPAQUE) ? RA_OPTIMAL : RA_ANY;
ph->p.rt_notify = pipe_rt_notify_sec;
ph->p.proto_state = PS_UP;
ph->p.core_state = ph->p.core_goal = FS_HAPPY;
/*
* Routes should be filtered in the do_rte_announce() (export
* filter for protocols). Reverse direction is handled by putting
* specified import filter to out_filter field of the phantom
* protocol.
*
* in_filter fields are not important, there is an exception in
* rte_update() to ignore it for pipes. We cannot just set
* P->in_filter to FILTER_ACCEPT, because that would break other
* things (reconfiguration, show-protocols command).
*/
ph->p.in_filter = FILTER_ACCEPT;
ph->p.out_filter = P->in_filter;
/*
* Connect the phantom protocol to the peer routing table, but
* keep it in the list of connections of the primary protocol,
* so that it gets disconnected at the right time and we also
* get all routes from both sides during the feeding phase.
*/
a = proto_add_announce_hook(P, p->peer);
a->proto = &ph->p;
return PS_UP;
}
static struct proto *
pipe_init(struct proto_config *C)
{
struct pipe_config *c = (struct pipe_config *) C;
struct proto *P = proto_new(C, sizeof(struct pipe_proto));
struct pipe_proto *p = (struct pipe_proto *) P;
p->peer = c->peer->table;
p->mode = c->mode;
P->accept_ra_types = (p->mode == PIPE_OPAQUE) ? RA_OPTIMAL : RA_ANY;
P->rt_notify = pipe_rt_notify_pri;
P->import_control = pipe_import_control;
P->reload_routes = pipe_reload_routes;
return P;
}
static void
pipe_postconfig(struct proto_config *C)
{
struct pipe_config *c = (struct pipe_config *) C;
if (!c->peer)
cf_error("Name of peer routing table not specified");
if (c->peer == C->table)
cf_error("Primary table and peer table must be different");
}
static void
pipe_get_status(struct proto *P, byte *buf)
{
struct pipe_proto *p = (struct pipe_proto *) P;
bsprintf(buf, "%c> %s", (p->mode == PIPE_OPAQUE) ? '-' : '=', p->peer->name);
}
static int
pipe_reconfigure(struct proto *P, struct proto_config *new)
{
struct pipe_proto *p = (struct pipe_proto *) P;
struct pipe_config *o = (struct pipe_config *) P->cf;
struct pipe_config *n = (struct pipe_config *) new;
if ((o->peer->table != n->peer->table) || (o->mode != n->mode))
return 0;
/* Update also the filter in the phantom protocol */
p->phantom->p.out_filter = new->in_filter;
return 1;
}
struct rtable *
pipe_get_peer_table(struct proto *P)
{
struct pipe_proto *p = (struct pipe_proto *) P;
return p->peer;
}
struct protocol proto_pipe = {
name: "Pipe",
template: "pipe%d",
postconfig: pipe_postconfig,
init: pipe_init,
start: pipe_start,
reconfigure: pipe_reconfigure,
get_status: pipe_get_status,
};
|
