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
|
#include <u.h>
#include <libc.h>
#include <ip.h>
#include <bio.h>
#include <ndb.h>
#include "dns.h"
/* get a notification from another system of a changed zone */
void
dnnotify(DNSmsg *reqp, DNSmsg *repp, Request *r)
{
RR *tp;
Area *a;
USED(r);
/* move one question from reqp to repp */
memset(repp, 0, sizeof(*repp));
tp = reqp->qd;
reqp->qd = tp->next;
tp->next = 0;
repp->qd = tp;
repp->id = reqp->id;
repp->flags = Fresp | Onotify | Fauth;
/* anything to do? */
if(zonerefreshprogram == nil)
return;
/* make sure its the right type */
if(repp->qd->type != Tsoa)
return;
syslog(0, logfile, "notification for %s", repp->qd->owner->name);
/* is it something we care about? */
a = inmyarea(repp->qd->owner->name);
if(a == nil)
return;
syslog(0, logfile, "serial old %lud new %lud", a->soarr->soa->serial, repp->qd->soa->serial);
/* do nothing if it didn't change */
if(a->soarr->soa->serial== repp->qd->soa->serial)
return;
a->needrefresh = 1;
}
/*
* this isn't going to work as a thread!
*/
static void
ding(void *u, char *msg)
{
USED(u);
if(strstr(msg, "alarm"))
noted(NCONT);
else
noted(NDFLT);
}
/* notify a slave that an area has changed. */
static void
send_notify(char *slave, RR *soa, Request *req)
{
int i, len, n, reqno, status, fd;
uchar obuf[Maxudp+Udphdrsize];
uchar ibuf[Maxudp+Udphdrsize];
RR *rp;
Udphdr *up = (Udphdr*)obuf;
char *err;
DNSmsg repmsg;
/* create the request */
reqno = rand();
n = mkreq(soa->owner, Cin, obuf, Fauth | Onotify, reqno);
/* get an address */
if(strcmp(ipattr(slave), "ip") == 0) {
parseip(up->raddr, slave);
} else {
rp = dnresolve(slave, Cin, Ta, req, nil, 0, 1, 1, &status);
if(rp == nil)
return;
parseip(up->raddr, rp->ip->name);
rrfree(rp);
}
fd = udpport();
if(fd < 0)
return;
notify(ding);
/* send 3 times or until we get anything back */
for(i = 0; i < 3; i++){
syslog(0, logfile, "sending %d byte notify to %s/%I.%d about %s", n, slave, up->raddr, nhgets(up->rport), soa->owner->name);
if(udpwrite(fd, (Udphdr*)obuf, obuf+Udphdrsize, n) != n)
break;
alarm(2*1000);
len = udpread(fd, (Udphdr*)ibuf, ibuf+Udphdrsize, Maxudp);
alarm(0);
if(len <= Udphdrsize)
continue;
err = convM2DNS(&ibuf[Udphdrsize], len, &repmsg);
if(err != nil)
continue;
if(repmsg.id == reqno && (repmsg.flags & Omask) == Onotify)
break;
}
close(fd);
}
/* send notifies for any updated areas */
static void
notify_areas(Area *a, Request *req)
{
Server *s;
for(; a != nil; a = a->next){
if(!a->neednotify)
continue;
/* send notifies to all slaves */
for(s = a->soarr->soa->slaves; s != nil; s = s->next)
send_notify(s->name, a->soarr, req);
a->neednotify = 0;
}
}
/*
* process to notify other servers of changes
* (also reads in new databases)
*/
void
notifyproc(void *v)
{
Request req;
USED(v);
for(;;){
getactivity(&req);
notify_areas(owned, &req);
putactivity();
sleep(60*1000);
}
}
|