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
|
/*
* Copyright (c) 1995 John Hay. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Hay.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY John Hay AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL John Hay OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* IPX Routing Table Management Daemon
*/
#include "defs.h"
int dognreply = 1;
/*
* Process a newly received packet.
*/
void
sap_input(from, size)
struct sockaddr *from;
int size;
{
int newsize;
int sapchanged = 0;
struct sap_entry *sap;
struct sap_info *n;
struct interface *ifp = 0;
struct afswitch *afp;
struct sockaddr_ipx *ipxp;
ifp = if_ifwithnet(from);
ipxp = (struct sockaddr_ipx *)from;
if (ifp == 0) {
if(ftrace) {
fprintf(ftrace, "Received bogus packet from %s\n",
ipxdp_ntoa(&ipxp->sipx_addr));
}
return;
}
if (ftrace)
dumpsappacket(ftrace, "received", from, (char *)sap_msg , size);
if (from->sa_family >= AF_MAX)
return;
afp = &afswitch[from->sa_family];
size -= sizeof (u_short) /* command */;
n = sap_msg->sap;
switch (ntohs(sap_msg->sap_cmd)) {
case SAP_REQ_NEAR:
if (ftrace)
fprintf(ftrace, "Received a sap REQ_NEAR packet.\n");
if (!dognreply)
return;
sap = sap_nearestserver(n->ServType, ifp);
if (sap == NULL)
return;
sap_msg->sap_cmd = htons(SAP_RESP_NEAR);
*n = sap->sap;
n->hops = htons(ntohs(n->hops) + 1);
if (ntohs(n->hops) >= HOPCNT_INFINITY)
return;
newsize = sizeof(struct sap_info) + sizeof(struct sap_packet);
(*afp->af_output)(sapsock, 0, from, newsize);
if (ftrace) {
fprintf(ftrace, "sap_nearestserver %X %s returned:\n",
ntohs(n->ServType),
ifp->int_name);
fprintf(ftrace, " service %04X %-20.20s "
"addr %s.%04X metric %d\n",
ntohs(sap->sap.ServType),
sap->sap.ServName,
ipxdp_ntoa(&sap->sap.ipx),
ntohs(sap->sap.ipx.x_port),
ntohs(sap->sap.hops));
}
return;
case SAP_REQ:
if (ftrace)
fprintf(ftrace, "Received a sap REQ packet.\n");
sap_supply(from, 0, ifp, n->ServType, 0);
return;
case SAP_RESP_NEAR:
/* XXX We do nothing here, for the moment.
* Maybe we should check if the service is in our table?
*
*/
if (ftrace)
fprintf(ftrace, "Received a sap RESP_NEAR packet.\n");
return;
case SAP_RESP:
if (ftrace)
fprintf(ftrace, "Received a sap RESP packet.\n");
(*afp->af_canon)(from);
for (; size > 0; size -= sizeof (struct sap_info), n++) {
if (size < sizeof (struct netinfo))
break;
/*
* The idea here is that if the hop count is more
* than INFINITY it is bogus and should be discarded.
* If it is equal to INFINITY it is a message to say
* that a service went down. If we don't allready
* have it in our tables discard it. Otherwise
* update our table and set the timer to EXPIRE_TIME
* so that it is removed next time we go through the
* tables.
*/
if (ntohs(n->hops) > HOPCNT_INFINITY)
continue;
sap = sap_lookup(n->ServType, n->ServName);
if (sap == 0) {
if (ntohs(n->hops) == HOPCNT_INFINITY)
continue;
sap_add(n, from);
sapchanged = 1;
continue;
}
/*
* A clone is a different route to the same service
* with exactly the same cost (metric).
* They must all be recorded because those interfaces
* must be handled in the same way as the first route
* to that service. ie When using the split horizon
* algorithm we must look at these interfaces also.
*
* Update if from gateway and different,
* from anywhere and less hops or
* getting stale and equivalent.
*/
if (((ifp != sap->ifp) ||
!equal(&sap->source, from)) &&
(n->hops == sap->sap.hops) &&
(ntohs(n->hops) != HOPCNT_INFINITY)) {
register struct sap_entry *tsap = sap->clone;
while (tsap) {
if ((ifp == tsap->ifp) &&
equal(&tsap->source, from)) {
tsap->timer = 0;
break;
}
tsap = tsap->clone;
}
if (tsap == NULL) {
sap_add_clone(sap, n, from);
}
continue;
}
if ((ifp == sap->ifp) &&
equal(&sap->source, from) &&
(ntohs(n->hops) == ntohs(sap->sap.hops)))
sap->timer = 0;
else if (((ifp == sap->ifp) &&
equal(&sap->source, from) &&
(n->hops != sap->sap.hops)) ||
(ntohs(n->hops) < ntohs(sap->sap.hops)) ||
(sap->timer > (EXPIRE_TIME*2/3) &&
ntohs(sap->sap.hops) == ntohs(n->hops) &&
ntohs(n->hops) != HOPCNT_INFINITY)) {
sap_change(sap, n, from);
sapchanged = 1;
}
}
if (sapchanged) {
register struct sap_entry *sap;
register struct sap_hash *sh;
sap_supply_toall(1);
for (sh = sap_head; sh < &sap_head[SAPHASHSIZ]; sh++)
for (sap = sh->forw;
sap != (struct sap_entry *)sh;
sap = sap->forw)
sap->state &= ~RTS_CHANGED;
}
return;
}
}
|
